Dissertations / Theses: 'Microgrid energy management system'

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Garmabdari, Rasoul. "Multi-Energy Microgrid Systems Planning and Energy Management Optimisation." Thesis, Griffith University, 2020. http://hdl.handle.net/10072/398878.

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Conventional power systems are predominantly composed of centralised large-scale generation sites that provide electricity to a large number of customers in a top-down unidirectional fashion and through transmission and distribution networks. To increase penetration of Renewable Energy Resources (RES) into this traditional power system and promotion of Distributed Energy Resources (DER) concept as an effective solution to deal with the challenges being faced in the conventional power system such as the energy losses, peak demand, peak generation, the infrastructure depreciation, and environmental effect, Microgrid (MG) concept is introduced. MG is defined as a locally controlled small unit of the power system that usually is in interaction with the main grid and is regarded as the building blocks of future Smart Grids (SGs). However, these systems are also capable of operating independently and isolated from the main grid, particularly in remote areas where access to the main grid is impossible or there is a disruptive event on the power system. The emergence of cutting-edge advances in the energy conversion and energy storage technologies and their commercial availability as well as introduction of various lucrative grid services that both grid and customers can benefit from derived the planners and engineers to further expand the flexibility, resilience and efficiency of MGs. To achieve this, Multi-Energy Microgrid System (MEMGS) concept as an expanded definition of MG was introduced to improve the efficiency of conventional energy systems, reduce air pollution as well as energy utilisation. MEMGS incorporates various energy technologies such as axillary boiler, gas turbine, RESs, thermal and battery energy storage systems that are fed by multiple energywares such as gas and electricity to supply multiple types of demands simultaneously such as electrical, heating and cooling loads. However, the integration of clusters of various technologies and concurrent delivery of different energy services causes additional complexities into the modelling and optimisation of these systems due to the potential interactions of energy vectors and various technologies at the consumer level. The economic viability of MGs and MEMGSs rely on the configuration and operating management of the technologies. Therefore, is a need to develop an effective and efficient planning framework that can handle the interaction complexities and nonlinearities of the system, determining the most appropriate architecture, selecting the energy conversion and energy storage technologies and energy supply alternatives from a candidate pool. This thesis aims at addressing these challenges by initially developing a comprehensive and accurate dynamic model for MGs and MGESs components, investigating the technical and economic aspects, the nonlinear behaviour, maintenance and degradation phenomena, and uncertainties associated with technologies through Mixed-Integer Linear Programming (MILP) and Mixed Integer Quadratic Programming (MIQP). Then the established model is employed to establish and propose a multi-objective linearised planning optimisation approach. The architecture and choice of equipment of MEMGSs involve various elements such as availability and costs of the energy sources and equipment, and characteristics of the energy demand. Considering these factors, the proposed strategy allocates the size of the components utilised in the MGs and EMMGSs while meeting the defined performance indices such as degradation factor, reliability and grid power fluctuations smoothing indices. Once, the configuration and capacity of components are optimally determined, efficient energy management is required. The last part of this research focuses on energy management system scheduling and optimisation where the EMS scheduling module for MGs and MEMGSs are inspected considering the Time of Use tariff, peak shaving and valley filling functions, degradation of energy storage devices, along with the operating criteria and cost of the energy conversion units. Moreover, a real-time EMS solution is provided to deal with intermittent behaviour of RESs while participating in arbitrage market. The real-time EMS manages the energy flow optimally according to the acquired real-time data and its deviation from the original schedule attained in the scheduling optimisation stage. The primary objective of the EMS module development is to maximise profit while improving the performance of the MEMGSs. Throughout this research, the MILP and MIQP optimisation approach is adopted to achieve a fast convergence while avoiding complexity and long computation time that would cause due to the nonlinear behaviour and complex interaction of the technologies. Finally, having a practical insight into the challenges and concerns with connection adjacent MGs in distribution networks, an efficient centralised EMS optimisation framework is proposed to cope with the limitations and optimise the performance of the system, considering power losses, voltage deviations and nonlinear degradation of the components. The primary objective of this section of research is to achieve the optimal techno-economic solution.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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Tayab, Usman Bashir. "Novel Forecasting and Scheduling for Microgrid Energy Management System." Thesis, Griffith University, 2021. http://hdl.handle.net/10072/408937.

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The high penetration of renewable energy resources brought new challenges to the modern grid; therefore, new solutions and concepts need to be developed. The idea of a microgrid (MG) has been introduced to overcome the upcoming issues in modern grids. MG is a small-scale grid composed of renewable energy resources, energy storage, and load demand. MG makes decisions by itself and can operate in grid-connected or islanded mode depending on functionality. The microgrid energy management system (M-EMS) is the decision-making centre of MG. An M-EMS is composed of four modules which are known as forecasting, scheduling, data acquisition, and human-machine interface. However, the forecasting and scheduling modules are considered as the major modules among the four of them. The forecasting module is required in the M-EMS to predict the future power generation and consumption. The forecast data is the input to the scheduling module of M-EMS. Employing forecasting system in the M-EMS would increase the accuracy of the scheduling module. The scheduling module is responsible for controlling the power flow from/to the main grid. Additionally, it performs optimal day-ahead scheduling of available power generation resources to feed the load demand in a grid-connected MG for economical operation. Consequently, this research work presents four contributions in the area of M-EMS for grid-connected MG. The first contribution of this research is to presents a hybrid strategy for short-term forecasting of load demand in M-EMS, which is a combination of best-basis stationary wavelet packet transform and the Harris hawks algorithm-based feedforward neural network. The Harris hawks algorithm is applied to the feedforward neural network as an alternative learning algorithm to optimized the weights and biases of neurons. The proposed model is applied for load demand prediction of the Queensland electric market and compared with existing competitive models. The simulation results prove the effectiveness of the proposed method. The second contribution of this research is to design and proposed an ensemble forecasting strategy for solar PV power forecasting. The proposed ensemble strategy is based on a systematic combination of the tunicate swarm algorithm (TSA)-based multilayer perceptron neural network (TSA-MLPNN), TSA based least-square support vector machine (TSA-LSSVM), whales optimization algorithm (WOA) based MLPNN (WOAMLPNN), and WOA based LSSVM (WOA-LSSVM). The output of all the models is combined using the Bayesian model averaging method. The proposed ensemble strategy is validated through simulation of the real-time data of building N-78 Griffith University, Queensland. The simulation results demonstrated that the proposed strategy shows excellent performance in comparison with several existing competitive approaches. The third contribution of this research is to propose an optimum scheduling strategy, using a weighted salp swarm algorithm for M-EMS, to perform the optimal scheduling of available power resources to meet consumer demand and minimize the operating cost of grid-connected MG. The performance of the proposed scheduling strategy is validated through simulation using MATLAB and compared with standard particle swarm optimization (PSO) based scheduling strategy. The comparison shows that the proposed strategy outperforms the PSO based strategy. The final contribution of this research is to propose an M-EMS using an ensemble forecasting strategy and grey wolf optimization (GWO). In the proposed M-EMS, an ensemble forecasting strategy is used to accomplish short-term forecasting of PV power and load while the GWO is applied to perform the optimum scheduling of available power resources in grid-connected MG. A small-scale experiment is conducted using Raspberry Pi 3 B+ via python programming language to validate the effectiveness of the proposed M-EMS. The experimental results of the proposed M-EMS for the selected case prove the effectiveness of the proposed M-EMS. In summary, several forecasting and scheduling strategies have been proposed and validated for the M-EMS of a grid-connected MG.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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Vosloo, Arno. "Agent-based energy management system for remote community microgrid." Thesis, Cape Peninsula University of Technology, 2015. http://hdl.handle.net/20.500.11838/1188.

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thesis submitted in partial fulfilment of the requirements for the degree: Master of Technology: Electrical Engineering in the Faculty of Electrical Engineering at the Cape Peninsula University of Technology
Rural communities are often unable to access electrical energy due to their distant location away from the national grid. Renewable energy sources (RESs) make it possible to provide electrical energy to these isolated areas. Sustainable generation is possible at a local level and is not dependant on connection to a national power grid. Microgrids are small scale, stand-alone electricity networks that harness energy at its geographical location, from natural resources. These small scale power grids are either connected to a national grid or operate separately by obtaining their power from an RES. Microgrids are becoming increasingly popular because they can provide electricity, independently of the national grid. The size of microgrid systems are dependent on the amount of energy that needs to be drawn and the amount of energy that has to be stored. Mechanical and electrical system component sizes become bigger due to increased operational energy requirements. Increases in component sizes are required on growing power networks when higher current levels are drawn. Energy management of microgrids must thus be introduced to prevent overloading the power grid network and to extend the operational life of the storage batteries. Energy management systems consist of different components which are seen as operational units. Operational units are responsible for measurement, communication, decision–making and power supply switching control, to manipulate the power output to meet the energy demands. Due to the increasing popularity of DC home appliances, it is important to explore the possibility of keeping these microgrids on a DC voltage basis. Electrical generation equipment such as photovoltaic panels can be used to generate DC at designed voltage levels. The energy management system connects the user loads and generation units together to form the microgrid. The aim of this study was to carry out the design of an agent–based energy management system for rural and under-developed communities. It investigates how the control of the output of the energy management system can be carried out to service the loads. The simulations were done using the following software packages: Simulink, Matlab, and SimPowerSystems. PV sources, energy management system (EMS) and user load parameters are varied in the simulation software to observe how the control algorithm executes load shedding. A stokvel-type charge share concept is dealt with where the state-of-charge (SOC) of batteries and user consumption will determine how grid loads are managed. Load shedding within the grid is executed by monitoring energy flow and calculating how much energy is allowed to be used by each consumer. The energy management system is programmed to always provide the largest amount of energy to the consumer with the lowest energy consumption for each day. The batteries store surplus electrical energy during the day. Load shedding starts at 18:00 each day. Users will be disconnected from the grid whenever their allotted energy capacity were depleted.

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Wang, Xueying. "Energy management for islanded microgrid with energy storage systems." Thesis, Wang, Xueying (2018) Energy management for islanded microgrid with energy storage systems. Honours thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/44767/.

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Microgrid is a new form of electrical network interconnected with renewable energy resources mainly used for remote areas. A microgrid has two operational modes, grid-connected and isolated modes. In isolated mode operation, the microgrid needs to overcome the intermittent power generated by renewable energy resources (PV or wind turbines) as the amount of generation is largely affected by weather condition. In order to optimise the power dispatch and maintain power-quality for an islanded microgrid, an energy management system for a low-voltage islanded microgrid with an energy storage system (battery in this thesis) is presented. The main objective of this energy management system is to optimise power dispatch and to make effective use of power generated by renewable resources (solar power in this paper) for an islanded microgrid to achieve the purpose of installing an environmental friendly power grid. The proposed energy management system is divided into two parts. Firstly, the system determines the battery charging/discharging state and the backup DG operating time based on the power generated by PV, base DG and load demand in each time step. From the decision-making process, the battery power, battery state of charge and the backup DG operating time is available for the next stage of the energy management system. Secondly, the modified Gauss-Seidel load flow iteration process is run in MATLAB for computing the bus voltage and transmission line power losses in each time step. The Gauss-Seidel load flow analysis is a typical calculation strategy for evaluating the operation of power flow in an electrical network. In order to verify the effectiveness of the proposed energy management system, four case studies are provided in this report under different power profiles and load profiles. The energy management system is used not only for optimizing power dispatch for an isolated microgrid with renewable energy resources and an energy storage system, but also for sizing battery and diesel generators before the installation of the microgrid with reasonable prediction of load demand and renewable power generation.

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Moghimi, Mojtaba. "Modelling and Optimization of Energy Management Systems in Microgrids and Multi-Microgrids." Thesis, Griffith University, 2018. http://hdl.handle.net/10072/385882.

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With the new challenges brought by the high penetration of Renewable Energy Resources (RESs) into the modern grid, developing new solutions and concepts are necessary. Microgrid (MG) is one of the new concepts introduced to overcome upcoming issues in the modern electricity grids. MGs and Multi-Microgrids (MMGs) are defined as the building blocks of smart grids. MGs are the small units, where power generation and consumption happen at the same location and MG makes the decisions by itself. MGs can operate grid-connected or island mode depending on the functionality of the MG. Energy Management System (EMS) is the decision making centre of the MG. The data from the devices is received by the EMS and after processing, the commands are sent to the controllable components. Management of voltage, active and reactive power, neutral current, unit commitment and economic dispatch are of the tasks of EMS. In this PhD thesis, an optimal EMS for MGs and MMGs is developed. The main objective of this project by developing the EMS is to optimize the energy flow in the MGs and MMGs to obtain peak load shaving in a cost beneficial system. In order to achieve an efficient EMS, communication system, forecasting system, scheduling system, and optimization system are modelled and developed. Different types of EMS operation, centralized, decentralized and distributed, are investigated in this work to achieve the best combination for MMG EMS operation. The communication system is mainly utilizing Modbus TCP/IP protocol for data transmission at local level and Internet of Things (IoT) protocols (MQTT) for the global communication level. A communication operation algorithm is proposed to manage the MMG EMS under different communication operation modes and communication failure conditions. Furthermore, a monitoring system is developed to collect the data from different devices in the MG. The data is processed in the MG EMS and the commands are sent to components through the communication infrastructure. The link between MGs and MMGs is through the proposed two-level communication system, where the expansion of MGs to a MMG is investigated. In the MMG, MGs are functioning as a unit while having different priorities and operating under different policies. Each MG has its own MG EMS and the EMSs transfer information through the communication system between each other in either centralized, decentralized, distributed, or no communication modes under the MMG EMS. The forecasting system is required in the EMS to predict the future MG characteristics such as power generation and consumption. The forecasted data is the input to the optimization and scheduling system of EMS. Employing the forecasting system in the EMS would increase the accuracy of the optimization and scheduling systems. In this thesis, the timeseries-based forecasting algorithms are employed to predict next day’s active power using the load data, generation data, weather data and temperature data as the inputs. The heart of EMS is the scheduling and optimization system. The purpose of the scheduling system is to define the amount and the time of energy flow in the MG for different generation sources and consumption loads. Furthermore, scheduling system is responsible for peak load shaving and valley filling. On the other hand, the optimization system has the task of minimizing the operation costs of the MGs. The role of market in the scheduling and optimization is important. Time of Use (ToU) tariff is the pricing system, which determines the peak and off peak hours for energy usage pricing. In order to apply the optimization system, a model of the system, an objective function and systems constraints are defined, where aging of battery energy storage system (BESS), operational cost of components and MG cost benefits are considered. To operate the EMS scheduling and optimization system, IBM CPLEX Optimization Studio solver conducts the optimization while for the scheduling system, objective function and constraints are defined in MATLAB. In this thesis, a rule-based, MILP and MIQP optimization system for commercial MGs including electric vehicles (EVs) are proposed to investigate performance of MG EMS for different case studies. In this thesis, the literature for different scheduling and forecasting systems is investigated and different optimization algorithms are analysed. The communication protocols utilized in this research are described and compared to other protocols in the literature. In different chapters of this thesis, the modelling of MGs and MMG EMS, different modules of EMS, forecasting, optimization, scheduling and communication systems are described and analysed. A novel communication system for MMG EMS operation is proposed for commercial buildings. The performance of MG EMS and MMG EMS is examined for power and neutral current sharing, operation cost optimization, and demand peak shaving applications and results are compared to investigate the performance of proposed algorithms.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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He, Youbiao. "The Energy Management of Next-generation Microgrid Systems." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1500907510831555.

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Darden, Kelvin S. "Smart Microgrid Energy Management Using a Wireless Sensor Network." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404560/.

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Modern power generation aims to utilize renewable energy sources such as solar power and wind to supply customers with power. This approach avoids exhaustion of fossil fuels as well as provides clean energy. Microgrids have become popular over the years, as they contain multiple renewable power sources and battery storage systems to supply power to the entities within the network. These microgrids can share power with the main grid or operate islanded from the grid. During an islanded scenario, self-sustainability is crucial to ensure balance between supply and demand within the microgrid. This can be accomplished by a smart microgrid that can monitor system conditions and respond to power imbalance by shedding loads based on priority. Such a method ensures security of the most important loads in the system and manages energy by automatically disconnecting lower priority loads until system conditions have improved. This thesis introduces a prioritized load shedding algorithm for the microgrid at the University of North Texas Discovery Park and highlight how such an energy management algorithm can add reliability to an islanded microgrid.

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Moussa, Hassan. "Contribution to the Decentralized Energy Management of Autonomous AC-Microgrid." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0161/document.

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Cette thèse porte sur des micro-réseaux AC isolées qui permettent l’intégration des ressources énergétiques distribuées (DER) pouvant fournir leur énergie d'alimentation existante de manière contrôlée pour assurer le bon fonctionnement global du système. L'interconnexion d'un DER à une micro-réseau s'effectue habituellement en utilisant un convertisseur d'interface distribué (DIC) (i.e. un bloc d'interface d'électronique de puissance générale) qui est constitué d’un module de convertisseur à l'entrée de la source, un onduleur de tension (VSI), un module d'interfaçage de sortie, et le module de commande. Dans cette thèse on réalise plusieurs lois de commande basées sur des méthodes décentralisées. L'accent principal est mis sur les fonctions "Droop" qui ont la tâche de maintenir un équilibre de distribution d'énergie entre les différentes sources énergétiques connectées à la micro-réseau. L'objectif est d'assurer la stabilité du système et d’améliorer les performances dynamiques en partageant la puissance entre les différents générateurs d’électricité distribués (DGs) en fonction de leur puissance nominale. Le développement d'une analyse de stabilité en boucle fermée s’avère utile pour étudier la dynamique du système afin d'obtenir une réponse transitoire souhaitée qui permet d'identifier les paramètres de contrôle de boucle appropriés. L'amélioration de la qualité d’énergie des micro-réseaux est également un objectif de cette thèse. La réduction des distorsions harmoniques de la tension de sortie en présence de charges linéaires et non linéaires est prise en compte dans nos travaux. D'autres aspects seront étudiés sur la façon de traiter les charges constantes connectées au réseau et les grandes perturbations qu’ils produisent. Cela donne lieu à d'autres études de recherche portant sur la stabilité grand signal des micro-réseaux
This thesis deals with islanded AC microgrid that allows any integration of Distributed Energy Resources (DERs) that may provide their existing supply energy in a controlled manner to insure overall system functioning. The interconnection of a DER to a microgrid is done usually by using a Distributed Interface Converter (DIC), a general power electronics interface block, which consists of a source input converter module, a Voltage Source Inverter module (VSI), an output interface module, and the controller module. The thesis realizes several control laws based on decentralized methods. The major focus is on the Droop functions that are responsible for providing a power distribution balance between different Energy Resources connected to a microgrid. The aim is to insure system stability and better dynamic performance when sharing the power between different DGs as function to their nominal power. Developing a closed loop stability analysis is useful for studying system dynamics in order to obtain a desired transient response that allows identifying the proper loop control parameters. Power Quality enhancement in microgrids is also a purpose of this research. The reduction of harmonic distortions of the output voltage when supplying linear and non-linear loads are taken in consideration in this thesis. Further aspects will be studied about how to deal with constant power loads connected to the grid and the large perturbations exerted. This results to further research studies that deal with large-signal stability of microgrids

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Lanas, Montecinos Fernando José, and Estevez Guillermo Jiménez. "Design of a robust energy management system for a grid-connected microgrid providing services." Tesis, Universidad de Chile, 2019. http://repositorio.uchile.cl/handle/2250/172645.

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Tesis para optar al grado de Magíster en Ciencias de la Ingeniería, Mención Eléctrica
Se define una microrred como una agrupación de cargas y recursos energéticos distribuidos que funciona como un único sistema controlable, capaz de operar en paralelo o aislado de la red eléctrica. Las microrredes son proveedores de energía locales que pueden reducir los gastos de energía, reducir las emisiones, aumentar la confiabilidad y son alternativas de energización emergentes. El correcto uso de sus recursos energéticos disponible permite lograr una operación más eficiente en una microrred, por ejemplo; reducir sus costos, mejorar ingresos, alargar la vida útil de los equipos y limitar el impacto ambiental. Algunos de estos objetivos se contraponen y es por esto que es necesario compensarlos para obtener el mejor despacho energético. Por esta razón el uso de un sistema de gestión de energía para microrredes cobra gran importancia. En este trabajo se desarrollaron modelos matemáticos y luego se implementaron en una herramienta computacional para el despacho energético óptimo de microrredes, con énfasis en tres aspectos. Primero, los servicios complementarios que una microrred puede ofrecer: arbitraje de energía, reducción de emisiones, reducción de potencia punta, reserva de potencia en giro y ofertas de reducción de consumo. Segundo, un modelo de almacenamiento de baterías enfocado en seis fenómenos: envejecimiento cíclico y calendario, la ley de Peukert, la pérdida de capacidad, autodescargas y la limitación de carga/descarga. Tercero, se incluye un módulo maestro-esclavo para lidiar con la estocasticidad ante problemas intempestivos en la red, manteniendo así la confiabilidad de la microrred cuando se aísla, aun si esta ofrece servicios. Estos tres aspectos son integrados en un modelo de programación lineal entera mixta para el despacho óptimo de una microrred, minimizando los costos de operación y reinversión. En el presente trabajo, se simulan la operación de tres microrredes reales bajo diferentes escenarios cada uno. El primer caso es la microrred aislada de Huatacondo, el segundo es la microrred conectada de CIGRE y el tercero es la microrred conectada de la cárcel de Santa Rita. Los resultados obtenidos muestran reducción en los costos de hasta 4.3% en la microrred de Huatacondo, hasta 2.9% para CIGRE y hasta 7% para Santa Rita al considerar servicios y utilizando un modelo detallado de almacenamiento. En el caso de la microrred aislada de Huatacondo, la reducción se basó principalmente en la extensión de la vida útil del banco de baterías. Para las dos microrredes conectadas los servicios más atractivos fueron ofrecer sus capacidades flexibles no utilizadas a la red. Esto considera servicios como reducción de consumo, reducción de demanda punta o reserva en giro. Servicios enfocados en transferencia de altos volúmenes de energía, como el arbitraje de energía, no fueron atractivos dado el costo asociado al uso de equipos de almacenamiento.

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Zia, Muhammad Fahad. "On energy management optimization for microgrids enriched with renewable energy sources Microgrids energy management systems: a critical review on methods, solutions, and prospects, in Applied Energy 222, July 2018 Optimal operational planning of scalable DC microgrid with demand response, islanding, and battery degradation cost considerations, in Applied Energy 237, March 2019 Energy management system for an islanded microgrid with convex relaxation, in IEEE Transactions on Industry Applications 55, Nov.-Dec. 2019 Microgrid transactive energy: review, architectures, distributed ledger technologies, and market analysis, in IEEE Access, January 2020." Thesis, Brest, 2020. http://theses-scd.univ-brest.fr/2020/These-2020-SPI-Genie_electrique-ZIA_Muhammad_Fahad.pdf.

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Le réseau électrique actuel est confronté à plusieurs défis liés aux exigences environnementales, à l'augmentation de la demande mondiale d'électricité, aux contraintes de fiabilité élevées, à la nécessité d’une énergie décarbonisée et aux restrictions de planification. Afin d’évoluer vers un système d'énergie électrique respectueux de l’environnement et intelligent, les installations de production centralisées sont de nos jours transformées en de plus petites centrales de génération distribuées. Le concept de micro-réseau émerge ainsi. Le micro-réseau peut être considéré comme un système de distribution basse tension avec un ensemble de charges contrôlables et de ressources énergétiques distribuées, qui peuvent inclure de nombreuses sources d'énergie renouvelables et des systèmes de stockage d'énergie. La gestion d’énergie d'un grand nombre de ressources énergétiques distribuées est nécessaire au bon fonctionnement d'un micro-réseau afin d’en assurer la stabilité, la fiabilité et la disponibilité. Par conséquent,un système de gestion d'énergie est au coeur de l'exploitation des micro-réseaux afin d’en assurer un développement économique et durable. À cet égard, cette thèse se focalise sur la proposition de modèles d'optimisation de système de gestion de l'énergie pour une exploitation optimale des micro-réseaux. Une gestion d’énergie optimale requiert la prise en compte de plusieurs contraintes techniques, économiques et environnementales. De plus, ces travaux de recherche prennent en considération un modèle pratique du coût de dégradation des batteries Li-ion. Le problème de gestion d’énergie optimale se traduit ainsi par un problème d’optimisation sous contraintes. La fonction objective regroupe le coût d'exploitation des générateurs distribués, le coût des émissions de gaz à effet de serre des sources de production conventionnelles, l’obligation d’une utilisation maximale des sources d'énergie renouvelables, le coût de dégradation des batteries, les différentes incitations afin de modifier le profil de la demande et des pénalités en cas de délestage. Les contraintes quant à elles sont liées aux contraintes techniques des différents sous-systèmes du micro-réseau. Par ailleurs, un modèle conceptuel complet à sept couches est également développé afin de fournir des informations normalisées sur la mise en oeuvre d’une nouvelle économie de l’énergie
The current electric power system isfacing the challenges of environmental protection,increasing global electricity demand, high reliability requirement, cleanliness of energy, and planning restrictions. To evolve towards green and smart electric power system, centralized generating facilities are now being transformed into smaller and more distributed generations. As a consequence, the concept of microgrid emerges, where a microgrid can operate as a single controllable system and can be assumed as a cluster of loads and distributed energy resources, which may include many renewable energy sources and energy storage systems. The energy management of large numbers of distributed energy resources is needed for reliable operation of microgrid system. Therefore, energy management is the fundamental part of the microgrid operation for economical and sustainable development. In this regard, this thesis focuses on proposing energy management optimization models for optimal operation of microgrid system that include proposed practical Li-ion battery degradation cost model. These different energy management models include objective functions of operating cost of distributed generators, emission cost of conventional generation source, maximum utilization of renewable energy sources, battery degradation cost, demand response incentives, and load shedding penalization cost, with microgrid component and physical network constraints. A comprehensive conceptual seven layer model is also developed to provide standardized insights in implementing real transactive energy systems

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deSa, Michael E. "An Original Microgrid Business Model Determines an Imminent New Asset Market." Case Western Reserve University Doctor of Management / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=casedm1568628001000343.

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Mousavi, Navid. "The integration of pumped hydro storage systems into PV microgrids in rural areas." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2020. https://ro.ecu.edu.au/theses/2345.

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Photovoltaic (PV) systems are popular in rural areas because they provide low cost and clean electricity for homes and irrigation systems. The primary challenge of PV systems is their intermittent nature. The typical solution is storing energy in batteries; however, they are expensive and possess a short lifespan. This research proposes a new type of pumped hydro storage (PHS) which can be implemented as an alternative to batteries. The components of the system are modelled to consider losses of the system accurately. The mathematic model developed in this project assists the management system to make more efficient decisions. The proposed storage is integrated into a farmhouse that has a PV pumping system where economic aspects of implementing the proposed storage is investigated. The integration of the proposed PHS into a microgrid needs a management system to make this system efficient and 3 cost-effective. This research proposes a multi-stage management system to schedule and control the microgrid components for optimal integration of the PHS. The designed management system is able to manage the pump, turbine, and irrigation time on real-time taking into account both present and future conditions of the microgrid. This study investigates the technical aspects of the proposed system. The PHS and the management system are tested experimentally in a setup installed at smart energy laboratory at Edith Cowan university. Data used in this project are real data collected in the laboratory in order to have a realistic analysis. Economic analysis is done in different sizes with different conditions. Results indicate that the proposed system has a short payback period and a large lifetime benefit, featuring as a cost-effective and sustainable energy storage system for use in rural areas. Video abstract: https://youtu.be/VuyEvHRY7W8

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Qian, Hao. "A High-Efficiency Grid-Tie Battery Energy Storage System." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/29008.

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Lithium-ion based battery energy storage system has become one of the most popular forms of energy storage system for its high charge and discharge efficiency and high energy density. This dissertation proposes a high-efficiency grid-tie lithium-ion battery based energy storage system, which consists of a LiFePO4 battery based energy storage and associated battery management system (BMS), a high-efficiency bidirectional ac-dc converter and the central control unit which controls the operation mode and grid interface of the energy storage system. The BMS estimates the state of charge (SOC) and state of health (SOH) of each battery cell in the pack and applies active charge equalization to balance the charge of all the cells in the pack. The bidirectional ac-dc converter works as the interface between the battery pack and the ac grid, which needs to meet the requirements of bidirectional power flow capability and to ensure high power factor and low THD as well as to regulate the dc side power regulation. A highly efficient dual-buck converter based bidirectional ac-dc converter is proposed. The implemented converter efficiency peaks at 97.8% at 50-kHz switching frequency for both rectifier and inverter modes. To better utilize the dc bus voltage and eliminate the two dc bus bulk capacitors in the conventional dual-buck converter, a novel bidirectional ac-dc converter is proposed by replacing the capacitor leg of the dual-buck converter based single-phase bidirectional ac-dc converter with a half-bridge switch leg. Based on the single-phase bidirectional ac-dc converter topology, three novel three-phase bidirectional ac-dc converter topologies are proposed. In order to control the bidirectional power flow and at the same time stabilize the system in mode transition, an admittance compensator along with a quasi-proportional-resonant (QPR) controller is adopted to allow smooth startup and elimination of the steady-state error over the entire load range. The proposed QPR controller is designed and implemented with a digital controller. The entire system has been simulated in both PSIM and Simulink and verified with hardware experiments. Small transient currents are observed with the power transferred from rectifier mode to inverter mode at peak current point and also from inverter mode to rectifier mode at peak current point. The designed BMS monitors and reports all battery cells parameters in the pack and estimates the SOC of each battery cell by using the Coulomb counting plus an accurate open-circuit voltage model. The SOC information is then used to control the isolated bidirectional dc-dc converter based active cell balancing circuits to mitigate the mismatch among the series connected cells. Using the proposed SOC balancing technique, the entire battery storage system has demonstrated more capacity than the system without SOC balancing.
Ph. D.

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14

Marzband, Mousa. "Experimental validation of optimal real-time energy management system for microgrids." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/145069.

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Nowadays, power production, reliability, quality, efficiency and penetration of renewable energy sources are amongst the most important topics in the power systems analysis. The need to obtain optimal power management and economical dispatch are expressed at the same time. The interest in extracting an optimum performance minimizing market clearing price (MCP) for the consumers and provide better utilization of renewable energy sources has been increasing in recent years. Due to necessity of providing energy balance while having the fluctuations in the load demand and non-dispatchable nature of renewable sources, implementing an energy management system (EMS) is of great importance in Microgrids (MG). The appearance of new technologies such as energy storage (ES) has caused increase in the effort to present new and modified optimization methods for power management. Precise prediction of renewable energy sources power generation can only be provided with small anticipation. Hence, for increasing the efficiency of the presented optimization algorithm in large-dimension problems, new methods should be proposed, especially for short-term scheduling. Powerful optimization methods are needed to be applied in such a way to achieve maximum efficiency, enhance the economic dispatch as well as provide the best performance for these systems. Thus, real-time energy management within MG is an important factor for the operators to guarantee optimal and safe operation of the system. The proposed EMS should be able to schedule the MG generation with minimum information shares sent by generation units. To achieve this ability, the present thesis proposes an operational architecture for real time operation (RTO) of a MG operating in both islanding and grid-connected modes. The presented architecture is flexible and could be used for different configurations of MGs in different scenarios. A general formula is also presented to estimate optimum operation strategy, cost optimization plan and the reduction of the consumed electricity combined with applying demand response (DR). The proposed problem is formulated as an optimization problem with nonlinear constraints to minimize the cost related to generation sources and responsive load as well as reducing MCP. Several optimization methods including mixed linear programming, pivot source, imperialist competition, artificial bee colony, particle swarm, ant colony, and gravitational search algorithms are utilized to achieve the specified objectives. The main goal of the thesis is to validate experimentally the design of the real-time energy management system for MGs in both operating modes which is suitable for different size and types of generation resources and storage devices with plug-and-play structure. As a result, this system is capable of adapting itself to changes in the generation and storage assets in real-time, and delivering optimal operation commands to the assets quickly, using a local energy market (LEM) structure based on single side or double side auction. The study is aimed to figure the optimum operation of micro-sources out as well as to decrease the electricity production cost by hourly day-ahead and real time scheduling. Experimental results show the effectiveness of the proposed methods for optimal operation with minimum cost and plug-and-play capability in a MG. Moreover, these algorithms are feasible from computational viewpoints while having many advantages such as reducing the peak consumption, optimal operation and scheduling the generation unit as well as minimizing the electricity generation cost. Furthermore, capabilities such as the system development, reliability and flexibility are also considered in the proposed algorithms. The plug and play capability in real time applications is investigated by using different scenarios.

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Mondal, Abrez. "ANALYSIS AND MITIGATION OF FREQUENCY DISTURBANCES IN AN ISLANDED MICROGRID." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492563068162654.

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16

Bai, Wenshuai. "DC Microgrid optimized energy management and real-time control of power systems for grid-connected and off-grid operating modes." Thesis, Compiègne, 2021. http://www.theses.fr/2021COMP2586.

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Le travail de recherche de cette thèse se concentre sur l’élaboration de deux modes de fonctionnement du microréseau à savoir : mode connecté au réseau, mode hors réseau comprenant les modes îloté et isolé. Le problème de la défaillance du réseau en mode connecté au réseau et la faible fiabilité de l'alimentation électrique en mode hors réseau doivent être résolues. Ainsi, le but de cette thèse est de proposer un microréseau DC combinant à la fois les avantages du mode connecté au réseau et ceux du mode isolé. On obtient ainsi un microréseau DC qu’on peut qualifier de complet. Le microréseau DC complet contient les sources d'énergie renouvelables, le stockage et le réseau public, et les sources de secours sont utilisées pour réduire le délestage. Dans ce microréseau DC, un système de supervision est proposé dans le but de gérer le flux des puissances. La gestion de la puissance en temps réel dans la couche opérationnelle du système de supervision permet de maintenir l'équilibre de puissance. Dans la couche d'optimisation du système de supervision, l'optimisation journalière est proposée afin de minimiser le coût d'exploitation global. Les résultats de la simulation montrent que le microréseau DC complet peut minimiser les coûts d'exploitation. Ensuite, le système de supervision prend en compte l'efficacité dynamique du convertisseur pour résoudre le problème lié à la qualité de la puissance du microréseau qui peut être dégradée à cause de la tension instable du bus DC. Les résultats de la simulation montrent que la prise en compte de l'efficacité dynamique du convertisseur dans la couche opérationnelle du système de supervision permet de réduire les fluctuations de la tension du bus DC. En ce qui concerne l'importance de la prédiction PV pour l'optimisation de la veille, deux modèles de prédiction sont étudiés et comparés pour donner une puissance de prédiction PV précise. Les résultats montrent que les deux modèles ont presque les mêmes résultats
This thesis focus on the research of the DC microgrid following two operation models: grid-connected mode, and off-grid mode including the islanded and isolated modes. The aim of this thesis is to propose a DC microgrid combining the advantages of the grid-connected or the off-grid mode, which named full DC microgrid. ln the full DC microgrid, the renewable energy sources, storage, and public grid are included, and the back-up sources also applied to reduce the load shedding. ln the full DC microgrid, a supervisory system is proposed to manage the power. The real-time power management in the operational layer of the supervisory system can keep the power balance. ln the optimization layer of the supervisory system, the day-ahead optimization is proposed to achieve the global minimal operation cost. The simulation results show that the full DC microgrid combines both advantages of the grid-connected and the off-grid mode to minimize the operating cost. Then, the supervisory system considers the dynamic efficiency of the converter to solve the problem that the power quality of the microgrid is degraded due to the unstable DC bus voltage caused by the inaccurate power control. The simulation results show that considering the dynamic efficiency of the converter in the operational layer of the supervisory system, the fluctuation of the DC bus voltage can be reduced. Regarding the importance of the PV prediction for the day-ahead optimization, two prediction modes are studied and compared to give a robust PV prediction power. The results are that the two models almost have the same results

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Farhadi, Mustafa. "Hybrid Energy Storage Implementation in DC and AC Power System for Efficiency, Power Quality and Reliability Improvements." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2471.

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Battery storage devices have been widely utilized for different applications. However, for high power applications, battery storage systems come with several challenges, such as the thermal issue, low power density, low life span and high cost. Compared with batteries, supercapacitors have a lower energy density but their power density is very high, and they offer higher cyclic life and efficiency even during fast charge and discharge processes. In this dissertation, new techniques for the control and energy management of the hybrid battery-supercapacitor storage system are developed to improve the performance of the system in terms of efficiency, power quality and reliability. To evaluate the findings of this dissertation, a laboratory-scale DC microgrid system is designed and implemented. The developed microgrid utilizes a hybrid lead-acid battery and supercapacitor energy storage system and is loaded under various grid conditions. The developed microgrid has also real-time monitoring, control and energy management capabilities. A new control scheme and real-time energy management algorithm for an actively controlled hybrid DC microgrid is developed to reduce the adverse impacts of pulsed power loads. The developed control scheme is an adaptive current-voltage controller that is based on the moving average measurement technique and an adaptive proportional compensator. Unlike conventional energy control methods, the developed controller has the advantages of controlling both current and voltage of the system. This development is experimentally tested and verified. The results show significant improvements achieved in terms of enhancing the system efficiency, reducing the AC grid voltage drop and mitigating frequency fluctuation. Moreover, a novel event-based protection scheme for a multi-terminal DC power system has been developed and evaluated. In this technique, fault identification and classifications are performed based on the current derivative method and employing an artificial inductive line impedance. The developed scheme does not require high speed communication and synchronization and it transfers much less data when compared with the traditional method such as the differential protection approach. Moreover, this scheme utilizes less measurement equipment since only the DC bus data is required.

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Gkiala, Fikari Stamatia. "Modeling and Simulation of an Autonomous Hybrid Power System." Thesis, Uppsala universitet, Fasta tillståndets fysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-267767.

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In this report, the modeling process and operation of an autonomous hybrid power system is studied. It is built based on a hypothetical case study of electrification of a remote village of 100 inhabitants in Kenya. The power demand is estimated and the costs of equipment components are specified after extensive research, so that the techno-economical design of the system can be carried out. The microgrid consists of photovoltaics, wind turbine, batteries, diesel genset, basic loads and water pumping and purification load. The system is modeled and simulated in terms of power management and its operation as well as the performance of the dispatch strategy is assessed. Problems like the management of extra power or tackling the deficit of power in the system are addressed. The model represents reliably the behavior of the microgrid and several improving actions are suggested.

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Tulpule, Pinak J. "Control and optimization of energy flow in hybrid large scale systems - A microgrid for photovoltaic based PEV charging station." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313522717.

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Marín, Collazos Luis Gabriel. "Hierarchical energy management system based on fuzzy prediction intervals for operation and coordination of microgrids." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/170000.

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Tesis para optar al grado de Doctor en Ingeniería Eléctrica
The integration of large numbers of Distributed Energy Resources (DERs) into the distribution system could take place either by reinforcement of the existing network assets, or the incorporation of active management of flexible resources into different sections of the distribution network. For active management of a distribution network, the design of control strategies is necessary for an efficient and reliable large-scale integration of DERs. Besides the benefit of supporting the use of renewable energy sources, DERs play an important role in improving the resilience and sustainability of the electricity distribution system and also in the generation of new market opportunities. In this thesis, the active management of DERs is proposed using a hierarchical energy management system (EMS) applied to "Energy Communities". Energy communities are a concept which allows different end users to cooperate in their energy interactions with the aim of maximising their self-consumption, minimising energy costs, reducing peak power levels or a combination of these and other beneficial goals as well. The hierarchical EMS proposed allows incorporating mechanisms to ensure both the realisation of short-term power balancing objectives and long-term energy management, benefiting the microgrid owner and the distribution network operator. The hierarchical EMS is designed in two levels: main grid level and microgrid level. At the microgrid level, a real-time local rule-based controller is proposed and at the higher level, a Robust model predictive control (MPC) is used to manage the uncertainty associated with renewable distributed generation and electricity demand. The uncertainty is incorporated into the Robust MPC controller based on fuzzy prediction interval models in order to help the system to be prepared for errors in the predictions that might yield sub-optimal decisions. Several case studies are used to test the performance of the hierarchical EMS for the operation and coordination of microgrids. Robust EMS based on fuzzy prediction interval models is compared to the deterministic EMS and with a basic EMS without energy storage system (ESS). The results show that the deterministic and Robust EMSs provide improvements over the case without ESS, as they offer mechanisms for efficient energy management. The incorporation of an ESS into the energy community benefits both the end user, by reducing energy cost, and the distribution network operator, by limiting the peak power levels and enabling increased penetration of distributed generation (DG). Additionally, the hierarchical EMS is able to keep the community power flow close to the reference power defined by the higher level controller with minimum energy cost, among other benefits. Finally, end users operating as Energy Communities can optimise the use of DG and the size of the ESS required.

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Mahmoud, Thair. "Optimal power generation in microgrids using agent-based technology." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/599.

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The existing power grids that form the basis of the respective electrical power infrastructures for various states and nations around the world, are expected to undergo a period of rapid change in the near future. The key element driving this change is the emergence of the Smartgrid. The Smartgrid paradigm represents a transition towards an intelligent, digitally enhanced, two-way power delivery grid. The aim of the Smartgrid is to promote and enhance the e_cient management and operation of the power generation and delivery facilities, by incorporating advanced communications, information technology, automation, and control methodologies into the power grid proper. Smartgrid's are currently an active topic for research, where the research is strongly focused on developing new technologies such as: demand response, power generation management, pricing modelling and energy markets participation, power quality, and self-healing scenarios. In recent times, in both the United States of America and Europe, many new projects have begun which are specifically directed towards developing “Smartgrid” technologies. In Australia, the Federal Government has recently initiated funding plans to promote the commercialisation of renewable energy. In order to exploit these developments, Edith Cowan University (ECU); which is a High Voltage (HV) customer for the major utility network of Western Australia, and which owns its own transformers and Low Voltage (LV) network; is planning to integrate renewable energy suppliers within its LV network. The aim of this research is to introduce a smart decision making system, which can manage the operation of disparate power generation sources installed on a LV network (microgrid); such as that owned by ECU on its campuses. The proposed energy management system is to gather data in real-time, and it must be capable of anticipating and optimising energy needs for each operational scenario that the microgrid might be expected to experience. The system must take into account risk levels, while systematically favouring low economic and environmental costs. A management system application, based on autonomous and distributed controllers, is investigated in a virtual environment. The virtual environment being a full-scale simulation of ECU's microgrid; with solar panels, wind turbines, storage devices, gas gen-sets, and utility supply. Hence the simulation studies were conducted on the basis of realistic demand trends and weather conditions data. The major factors for reducing the cost of generation in the case study, were identified as being: 1) demand forecasting; 2) generation scheduling; 3) markets participation; and 4) autonomous strategies configuration, which is required to cope with the unpredictable operation scenarios in LV networks. Due to the high uncertainty inherent within the operational scenarios; an Artificial Intelligence (AI) deployment for managing the distributed sub-systems was identified as being an ideal mechanism for achieving the above mentioned objectives. Consequently it is proposed that Multi-Agent System (MAS) technology be deployed, to enable the system to respond dynamically to the unpredictable operational conditions by updating the method of analysis. The proposed system is to behave in a strategic manner when dealing with the expected operational scenarios, by aiming to achieve the lowest possible cost of power generation for the microgrid. The simulated system is based on realistic operational scenarios, which have been scaled to suit the size and type of load in the case study. The distributed intelligent modules have proven to be successful in achieving the potential benefits of the dynamic operational conditions, by minimising the cost of power generation. The distributed intelligent modules, which form the basis of the proposed management systems, have been designed to perform the following functions: 1. Provide accurate demand forecasts through the utilisation of an AI-based adaptive demand forecasting model. The novel demand-forecast modelling technique, which was introduced to model demand in the case study, has been utilised to supply reasonably accurate demand forecasts to other stages of processing in the management system. The forecasts are generated from this model, by monitoring and controlling the forecasting error to ensure consistent and satisfactory forecasts. 2. Make optimum decisions concerning the operation of the power generators by considering the economic and the environmental costs. In order to deal with the complexity of the operational conditions, a smart and adaptive generation scheduling method was implemented for the case study. The method was primarily applied to control the charging/ discharging process of the Storage Devices (SDs) among the other generators. The proposed method aims at controlling the resources, and extracting the benefit of having an hourly based variable generation cost. 3. Integrate the microgrid into the electricity market, in order to enable the microgrid to offer its spinning and non-spinning power generation reserve as Ancillary Services (AS) to the grid. To this end, studying the operational mechanisms of the Australian market was essential prior to building the proposed market participation rules which form an integral part of the proposed management system. As a result we used the market data, by approaching the market operators to create a semi-realistic competitive market environment for our simulations. Consequently, a smart and adaptive pricing mechanism, that adapts the AS prices to the amount of electricity on offer, and the level of demand in the market has been presented. The motivation for introducing the proposed management system, is to achieve a transition plan for current microgrids, so that they can have a commercial connection to the future Smartgrid. The results obtained in this work show that there is a signi_cant economic and environmental advantage to be gained from utilising intelligence when managing electricity generation within a power grid. As a consequence, selecting the appropriate management strategy is fundamental to the success of the proposed management system. In conclusion, modelling of the proposed strategies using MAS technology has proven to be a successful approach, and one that is able to reflect the human attitude; in making critical decisions and in reducing the cost of generation.

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Wei, Jin. "Modeling and Coordination of interconnected microgrids using distributed artificial intelligence approaches." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCA021.

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À mesure que les sources renouvelables pénètrent dans le système électrique actuel pour atténuer le réchauffement planétaire et la pénurie d’énergie, le concept de microréseau (MG) permet de réduire l’impact de la production intermittente sur le réseau de services publics. Il permet d'améliorer l’automatisation et l’intelligence du réseau électrique avec des caractéristiques plug-and-play. L’intégration d’un plus grand nombre de MG dans un réseau de distribution favorise le développement du réseau intelligent. Leur coordination pourrait conduire à une grande fiabilité du système avec un faible coût, et une forte résistance aux pannes électriques. La réalisation de ces profits repose sur des technologies développées de communication et de stratégies de contrôle.La répartition de la puissance dans les MG répartis tout en coordonnant les éléments au sein de chaque MG exige un contrôle décentralisé. L'approche multiagent permet de modéliser un réseau de MG comme un système physiquement distribué. Cette thèse étudie principalement le contrôle de coordination dans le réseau MG et sa modélisation à base d'agent.. L' objectif est de promouvoir la performance des contrôles en termes d’efficacité et de fiabilité. Deux méthodes sont envisagées pour permettre l’évolutivité du système, y compris la coordination avec les MG voisins et dans la zone de coordination étendue. Une plateforme de simulation est établie pour valider les approches proposées.Les stratégies de contrôle pour la coordination entre les MG et leurs voisins sont proposées afin de maintenir la charge complète et la sécurité tout en minimisant le coût de production. Le contrôle centralisé dans le groupe de coordination est appliqué à la gestion économique de l’énergie. Il utilise une méthode de Newton-Raphson pour répartir la puissance entre les MG voisins en simplifiant la relation entre le coût de production de MG et sa puissance de sortie. Une approche fondée sur le consensus est adoptée pour calculer le flux de puissance du réseau, et les résultats sont comparés avec la capacité maximale sur la ligne pour assurer un fonctionnement sûr. Pour améliorer encore les avantages économiques, l’approximation de la relation entre la puissance de production de MG et le coût de production est améliorée par une autre stratégie fondée sur la notion de marché. Il construit un marché pour le commerce d’électricité avec les voisins. Cette méthode préserve la vie privée de chaque MG. Le calcul du débit de puissance est simplifié pour être proportionnel à la différence d’angle entre les deux extrémités de la ligne de raccordement. Les deux stratégies sont testées sur plusieurs réseaux MG. Leur performance montre que les deux approches sont évolutives et pourraient économiquement compenser le manque d’approvisionnement en charge dans les MG défectueux.Pour la stratégie de contrôle avec une fiabilité et un profit plus élevés, une stratégie de coordination au sein d’une vaste zone sélectionnée de MG est proposée. L’élargissement de la zone de coordination en fonction des MG voisins fournit plus de sources d’énergie au MG. Il assure suffisamment de puissance pour compenser le déséquilibre et offre plus de choix pour la distribution de puissance. La sélection de la zone de coordination est réalisée par un algorithme évolutionnaire distribué. La programmation quadratique dans Gurobi est utilisée pour résoudre le problème de répartition de puissance. Un autre algorithme génétique est également adopté pour résoudre le problème de la répartition optimale de la puissance avec un coût de production quadratique pour la microturbine. La performance de cette stratégie est testée, et les résultats montrent qu’elle a des avantages en termes de fiabilité, d'évolutivité et de profit par rapport aux méthodes centralisées
As renewable sources penetrate the current electrical system to relief global warming and energy shortage, microgrid (MG) emerges to reduce the impact of intermittent generation on the utility grid. Additionally, it improves the automation and intelligence of the power grid with plug-and-play characteristics. Inserting more MGs into a distribution network promotes the development of the smart grid. Thus MG networks existing in the power system are in prospect. Coordinating them could gain a system with high reliability, low cost, and strong resistance to electrical faults. Achieving these profits relies on developed technologies of communication, control strategy, and corresponding algorithms.Dispatching power in distributed MGs while coordinating elements within the individual MG demands a decentralized control system, in which the multi-agent system possesses advantages. It is applied to the MG network for establishing a physically distributed system. Based on the multi-agent system, this thesis mainly studies the coordination control in the MG network and its modeling. It aims at promoting control performance in terms of efficiency, reliability, economic benefit, and scalability. Two methods are considered to enable the system scalability, including the coordination with neighboring MGs and within the extensive coordinating area. A simulation platform is established to validate the proposed approaches.The control strategies for coordination between MGs and their neighbors are proposed to maintain the complete load supply and global security operation while minimizing the generation cost. Centralized control in the coordination group is applied for economic energy management. It uses a Newton-Raphson method to dispatch power among neighboring MGs by simplifying the relationship between MG generation cost and its output power. An average consensus approach is adopted to calculate the caused network power flow, and the results are compared with the maximal capacity on the line to keep safe operation. To further improve the economic benefits, the approximation of the relationship between MG output power and the caused generation cost is improved by an another strategy based on the market concept. It builds a market for neighboring power trade. This method maintains the operation privacy of individual MG. Power flow calculation is simplified to be proportional to the angle difference between the two terminates of the connecting line. Both strategies are tested on several MG network. Their performance shows that both approaches possess scalability and could economically compensate for the lack of load supply in faulted MG.For the control strategy with higher reliability and profit, a coordination strategy within a selected extensive area of MGs is proposed. Expanding the coordination area based on neighboring MGs provides more energy sources to the demanded MG. It ensures enough power to compensate imbalance and offers more choices for power dispatching. The selection of the coordination area is based on a distributed evolutionary algorithm. Quadratic programming in Gurobi is used to solve the power dispatching problem. Another genetic algorithm is also adopted to solve the problem of optimal power dispatching with a quadratic generation cost for microturbine. The performance of this strategy is tested, and the results show that it has comprehensive advantages on reliability, scalability, and profit compared with centralized methods

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Leite, Neto Pedro Bezerra. "Contribuições para a operação energética e econômica de microrredes isoladas com fontes renováveis." Universidade Federal do Maranhão, 2017. http://tedebc.ufma.br:8080/jspui/handle/tede/1747.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
The development of microgrids was driven by the need to supply consumers with more stable and reliable electricity. The intermittent nature of renewable sources differs from the requirements of consumers - especially in isolated areas - who expect an uninterrupted and quality energy supply. Isolated microstrips may have available one or more renewable sources to be explored, configuring hybrid systems. Although such renewable sources are inexhaustible, energy conversion systems are capacity limited and need to be explored efficiently. Hybrid systems typically include solar photovoltaic and wind, already well studied. In this thesis are introduced the oceanic energies in their gradient and tidal currents forms. This thesis contributes to the efficient exploration of the oceanic sources, both as a single source as well as in a hybrid configuration. In relation to the isolated operation, the storage system is of fundamental importance. Considering the high costs of a battery bank over the total cost of the system, operating strategies that preserve its useful life while maintaining uninterrupted power supply are mandatory. Considering these aspects, in this work is proposed a dual energy storage system composed of two subsystems with diversified functions and submitted to different chage/discharge conditions. The purpose of this new strategy is a more efficient use of the storage system, since this operating regime becomes closer to the recommended by the battery manufacturers. The benefits of this strategy are reflected in the overall cost reduction of the microgrid. In order to achieve optimum operating strategies, a more accurate mathematical model of the batteries is used to reproduce the behavior of the batteries in a more realistic way. In addition, it is investigated the performance of operating strategies that allow maximum benefits to be obtained through the diversification of the microgrid energy matrix, by including hydrokinetic tidal sources. The motivation for including this source lies in its high potential, especially on the northern coast of Brazil. These benefits should be evaluated mainly through the more efficient use of the storage system as well as the reduction of the participation of fossil fuel units in the operation of isolated microgrids.
O desenvolvimento das microrredes foi impulsionado pela necessidade de suprir os consumidores com eletricidade de forma mais estável e confiável. A natureza intermitente das fontes renováveis se contrapõe às exigências dos consumidores - especialmente em áreas isoladas - que esperam por um fornecimento de energia sem interrupções e com qualidade. As microrredes isoladas podem ter disponíveis uma ou mais fontes renováveis para serem exploradas, configurando sistemas híbridos. Embora tais fontes renováveis sejam inesgotáveis, os sistemas de conversão de energia são limitados em capacidade e devem ser explorados com eficiência. Sistemas híbridos normalmente incluem energia solar fotovoltaica e eólica, já bastante estudadas. Nesta tese são introduzidas as energias oceânicas nas suas formas de gradiente e de correntes de marés. Esta tese contribui para a exploração eficiente de fontes oceânicas, tanto na operação como fonte única assim como em configuração híbrida. No que tange a operação isolada, o sistema de armazenamento tem importância fundamental. Considerando os elevados custos de um banco de baterias sobre o custo total do sistema, estratégias de operação que preservem sua vida útil, ao mesmo tempo que mantenham o fornecimento ininterrupto de energia, são mandatórias. Diante destes aspectos, neste trabalho é proposto um sistema dual de armazenamento de energia composto de dois subsistemas com funções diversificadas e submetidos a condições de carga/descarga diferentes. O objetivo desta nova estratégia consiste no uso mais eficiente do sistema de armazenamento, uma vez que esse regime de operação se torna mais próximo daquele recomendado pelos fabricantes de baterias. Os benefícios desta estratégia são refletidos na redução dos custos globais da microrrede. Para conseguir as estratégias de operação ótima, neste trabalho é utilizado um modelo matemático mais acurado das baterias a fim de reproduzir de forma mais realista o comportamento das baterias. Além disso, é investigado o desempenho de estratégias de operação que permitam obter o máximo de benefícios decorrentes da diversificação da matriz energética da microrrede, através da inclusão de fontes hidrocinéticas maremotrizes. A motivação para a inclusão desta fonte está no seu elevado potencial, em especial no litoral norte do Brasil. Estes benefícios devem ser avaliados especialmente quanto ao uso mais eficiente do sistema de armazenamento, assim como a redução da necessidade de participação de unidades baseadas em combustível fóssil na operação de microrredes isoladas.

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Unnikrishnan, Raveendran Nair. "Control and management of energy storage systems in microgrids." Doctoral thesis, TDX (Tesis Doctorals en Xarxa), 2020. http://hdl.handle.net/10803/671050.

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The rate of integration of the renewable energy sources in modern grids have significantly increased in the last decade. These intermittent, non-dispatchable renewable sources, though environment friendly tend to be grid unfriendly. This is precisely due to the issues pertaining to grid congestion, voltage regulation and stability of grids being reported as a result of the incorporation of renewable sources. In this scenario, the use of energy storage systems (ESS ) in electric grids is being widely proposed to overcome these issues. However, integrating energy storage systems alone will not compensate for the issue created by renewable generation. The control and management of the ESS should be done optimally so that their full capabilities are exploited to overcome the issues in the power grids and to ensure their lower cost of investment by prolonging ESS lifetime through minimising degradation. Motivated by this aspect this Ph.D work focusses on developing an efficient, optimal control and management strategy for ESS in a microgrid, especially hybrid ESS. The Ph.D work addresses this issue by proposing a hierarchical control scheme comprising of a lower power management and higher energy management stage with contributions in each stage. In the power management stage this work focusses on improving aspects of real time control of power converters interfacing ESS to grid and the microgrid system as whole. The work proposes control systems with improved dynamic behaviour for power converters based on the reset control framework. In the microgrid control the work presents a primary+secondary control scheme with improved voltage regulation performance under disturbances, using an observer. The real time power splitting strategies among hybrid ESS accounting for the ESS operating efficiencies and degradation mechanisms will also be addressed in the primary+secondary control of power management stage. The design criteria, stability and robustness analysis will be carried out, along with simulation or experimental verifications. In the higher level energy management stage, the contribution of this work involves application of an economic MPC framework for the management of ESS in microgrids. The work specifically addresses the problems of mitigating grid congestion from renewable power feed-in, minimising ESS degradation and maximising self consumption of generated renewable energy using the MPC based energy management system. A survey of the forecasting methods that can be used for MPC will be carried out and a neural network based forecasting unit for time series prediction will be developed. The practical issue of accounting for forecasting error in the decision making of MPC will be addressed and impact of the resulting conservative decision making on the system performance will be analysed. The improvement in performance with the proposed energy management scheme will be demonstrated and quantified.
La integración de las fuentes de energía renovables en las redes modernas ha aumentado significativamente en la última década. Estas fuentes renovables, aunque muy convenientes para el medio ambiente son de naturaleza intermitente, y son no panificables, cosa que genera problemas en la red de distribución. Esto se debe precisamente a los problemas relacionados con la congestión de la red y la regulación del voltaje. En este escenario, el uso de sistemas de almacenamiento de energía (ESS) en redes eléctricas está siendo ampliamente propuesto para superar estos problemas. Sin embargo, la integración de sistemas de almacenamiento de energía por sí solos no compensará el problema creado por la generación renovable. El control y la gestión del ESS deben realizarse de manera óptima, de modo que se aprovechen al máximo sus capacidades para superar los problemas en las redes eléctricas, garantizar un coste de inversión razonable y prolongar la vida útil del ESS minimizando su degradación. Motivado por esta problemática, esta tesis doctoral se centra en desarrollar una estrategia de control y gestión eficiente para los ESS integrados en una microrred, especialmente cuando se trata de ESS de naturaleza. El trabajo de doctorado propone un esquema de control jerárquico compuesto por un control de bajo nivel y una parte de gestión de energía operando a más alto nivel. El trabajo realiza aportaciones en los dos campos. En el control de bajo nivel, este trabajo se centra en mejorar aspectos del control en tiempo real de los convertidores que interconectan el ESS con la red y el sistema de micro red en su conjunto. El trabajo propone sistemas de control con comportamiento dinámico mejorado para convertidores de potencia desarrollados en el marco del control de tipo reset. En el control de microrred, el trabajo presenta un esquema de control primario y uno secundario con un rendimiento de regulación de voltaje mejorado bajo perturbaciones, utilizando un observador. Además, el trabajo plantea estrategias de reparto del flujo de potencia entre los diferentes ESS. Durante el diseño de estos algoritmos de control se tienen en cuenta los mecanismos de degradación de los diferentes ESS. Los algoritmos diseñados se validarán mediante simulaciones y trabajos experimentales. En el apartado de gestión de energía, la contribución de este trabajo se centra en la aplicación del un control predictivo económico basado en modelo (EMPC) para la gestión de ESS en microrredes. El trabajo aborda específicamente los problemas de mitigar la congestión de la red a partir de la alimentación de energía renovable, minimizando la degradación de ESS y maximizando el autoconsumo de energía renovable generada. Se ha realizado una revisión de los métodos de predicción del consumo/generación que pueden usarse en el marco del EMPC y se ha desarrollado un mecanismo de predicción basado en el uso de las redes neuronales. Se ha abordado el análisis del efecto del error de predicción sobre el EMPC y el impacto que la toma de decisiones conservadoras produce en el rendimiento del sistema. La mejora en el rendimiento del esquema de gestión energética propuesto se ha cuantificado.
La integració de les fonts d'energia renovables a les xarxes modernes ha augmentat significativament en l’última dècada. Aquestes fonts renovables, encara que molt convenients per al medi ambient són de naturalesa intermitent, i són no panificables, cosa que genera problemes a la xarxa de distribució. Això es deu precisament als problemes relacionats amb la congestió de la xarxa i la regulació de la tensió. En aquest escenari, l’ús de sistemes d'emmagatzematge d'energia (ESS) en xarxes elèctriques està sent àmpliament proposat per superar aquests problemes. No obstant això, la integració de sistemes d'emmagatzematge d'energia per si sols no compensarà el problema creat per la generació renovable. El control i la gestió de l'ESS s'han de fer de manera _optima, de manera que s'aprofitin al màxim les seves capacitats per superar els problemes en les xarxes elèctriques, garantir un cost d’inversió raonable i allargar la vida útil de l'ESS minimitzant la seva degradació. Motivat per aquesta problemàtica, aquesta tesi doctoral es centra a desenvolupar una estratègia de control i gestió eficient per als ESS integrats en una microxarxa, especialment quan es tracta d'ESS de natura híbrida. El treball de doctorat proposa un esquema de control jeràrquic compost per un control de baix nivell i una part de gestió d'energia operant a més alt nivell. El treball realitza aportacions en els dos camps. En el control de baix nivell, aquest treball es centra a millorar aspectes del control en temps real dels convertidors que interconnecten el ESS amb la xarxa i el sistema de microxarxa en el seu conjunt. El treball proposa sistemes de control amb comportament dinàmic millorat per a convertidors de potència desenvolupats en el marc del control de tipus reset. En el control de micro-xarxa, el treball presenta un esquema de control primari i un de secundari de regulació de voltatge millorat sota pertorbacions, utilitzant un observador. A més, el treball planteja estratègies de repartiment de el flux de potència entre els diferents ESS. Durant el disseny d'aquests algoritmes de control es tenen en compte els mecanismes de degradació dels diferents ESS. Els algoritmes dissenyats es validaran mitjanant simulacions i treballs experimentals. En l'apartat de gestió d'energia, la contribució d'aquest treball se centra en l’aplicació de l'un control predictiu econòmic basat en model (EMPC) per a la gestió d'ESS en microxarxes. El treball aborda específicament els problemes de mitigar la congestió de la xarxa a partir de l’alimentació d'energia renovable, minimitzant la degradació d'ESS i maximitzant l'autoconsum d'energia renovable generada. S'ha realitzat una revisió dels mètodes de predicció del consum/generació que poden usar-se en el marc de l'EMPC i s'ha desenvolupat un mecanisme de predicció basat en l’ús de les xarxes neuronals. S'ha abordat l’anàlisi de l'efecte de l'error de predicció sobre el EMPC i l'impacte que la presa de decisions conservadores produeix en el rendiment de el sistema. La millora en el rendiment de l'esquema de gestió energètica proposat s'ha quantificat.

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Salas, Puente Robert Antonio. "Gestión eficiente de los convertidores de potencia conectados al bus DC de una Microrred híbrida de generación distribuida." Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/118658.

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[ES] Dos aspectos críticos en la operación de una microrred son las estrategias de control y gestión de potencia implementadas, las cuales son esenciales para proporcionar su buen funcionamiento. La aplicación adecuada de dichas estrategias permite compensar los desequilibrios de potencia causados por la discontinuidad de la generación y de la demanda de energía en las microrredes. En este sentido, el objetivo global de estas estrategias de gestión es equilibrar adecuadamente el flujo de potencia en la microrred, mediante la aplicación de diferentes algoritmos que permiten cumplir con los criterios de estabilidad, protección, balance de potencia, transiciones, sincronización con la red y gestión adecuada de la microrred. En el caso de microrredes de pequeña escala de potencia con bajo número de generadores y sistemas de almacenamiento distribuidos, las estrategias de control centralizado ofrecen un alto nivel de flexibilidad para lograr funcionalidades avanzadas en la microrred y una adecuada distribución de la potencia entre los convertidores que la conforman. Esta tesis se ha enmarcado en el contexto de algoritmos de gestión centralizada de potencia de una microrred de generación distribuida en modo conectado a red. Los algoritmos presentados se pueden aplicar a los convertidores de potencia conectados al bus DC de una microrred AC/DC híbrida o en una microrred de DC, donde el despacho de potencia es observado y gestionado por un controlador central. Este último adquiere datos del sistema mediante una infraestructura de comunicaciones y estima la potencia que gestionará cada uno de los convertidores de potencia, sistemas de almacenamiento y cargas en funcionamiento. En este estudio se muestra la validación experimental de las estrategias de gestión aplicadas en la microrred desde el enfoque del comportamiento de los convertidores de potencia, de las baterías y las cargas ante dicha gestión. Se verifica la estabilidad de la microrred sometiendo a los convertidores a diferentes escenarios de funcionamiento. Estos escenarios pueden ser fluctuaciones en la irradiación, la demanda, el estado de carga de las baterías, los límites máximos de exportación/importación de potencia desde/hacia la microrred hacia/desde la red principal y de la tarifa eléctrica. Adicionalmente, se propone un sistema de almacenamiento de energía en baterías encargado de mantener el equilibrio de potencia en el bus de DC de la microrred que permite aprovechar las fuentes de generación renovables presentes en la microrred y maximizar el tiempo de servicio de las baterías mediante la aplicación de un algoritmo de carga de las baterías. Este último se ajusta al procedimiento de carga especificado por el fabricante, estableciendo las tasas de carga en función de los escenarios en que la microrred se encuentre. El procedimiento de carga en las baterías es fundamental para garantizar las condiciones adecuadas de operación de las mismas, ya que toman en consideración los parámetros establecidos por el fabricante, como son: tasas de carga/descarga, tensión máxima de carga, temperaturas de operación, etc.
[CAT] Dos dels aspectes crítics en l'operació d'una micro-xarxa són les estratègies de control i gestió de potència implementades, les quals són essencials per proporcionar el seu bon funcionament. L'aplicació adequada de dites estratègies permet compensar els desequilibris de potència causats per la discontinuïtat de la generació i demanda d'energia en les micro-xarxes. En aquest sentit, l'objectiu global de les nomenades estratègies de gestió és equilibrar adequadament el flux de potència en la micro-xarxa mitjançant l'aplicació de diferents algoritmes que permeten complir amb els criteris d'estabilitat, protecció, balanç de potència, transicions, sincronització amb la xarxa i gestió adequada de la micro-xarxa. En el cas de micro-xarxes de potència a petita escala i amb baix nombre de generadors i sistemes d'emmagatzematge distribuïts, les estratègies de control centralitzades ofereixen un alt nivell de flexibilitat per aconseguir funcionalitats avançades en la micro-xarxa i una adequada distribució de la potència entre els convertidors que la conformen. Aquesta tesi s'ha emmarcat al context d'algoritmes de gestió centralitzada de potència d'una micro-xarxa de generació distribuïda en mode de connexió a xarxa. Els algoritmes presentats es poden aplicar als convertidors de potència connectats al bus DC d'una micro-xarxa AC/DC hibrida o en una micro-xarxa de DC, on el despatx de potència és observat i gestionat per un controlador central. Aquest últim adquireix dades del sistema mitjançant una infraestructura de comunicacions i estima la potència que gestionarà cadascun dels convertidors de potència, sistemes d'emmagatzematge i càrregues en funcionament. En aquest estudi es mostren la validació experimental de les estratègies de gestió aplicades en la micro-xarxa des d'un enfocament dels convertidors de potència, de les bateries i les càrregues davant d'aquesta gestió. Es verifica l'estabilitat de la micro-xarxa exposant als convertidors a diferents escenaris de funcionament. Aquest escenaris poden ser fluctuants en la irradiació, la demanda, l'estat de càrrega de les bateries, els límits màxims d'exportació/importació de potència des de/cap a la micro-xarxa cap a/des de la xarxa principal i de la tarifa elèctrica. Addicionalment, es proposa un sistema d'emmagatzematge d'energia en bateries encarregats de mantindre l'equilibri de potència al bus DC de la micro-xarxa i que permet aprofitar les fonts de generació renovables presents en la micro-xarxa i maximitzar el temps de servei de les bateries mitjançant l'aplicació d'un algoritme de càrrega de bateries. Aquest últim s'ajusta al procediment de càrrega especificat pel fabricant, establint les taxes de càrrega en funció dels escenaris en que la micro-xarxa es trobe. El procediment de càrrega a les bateries es fonamental per garantir les condicions adequades d'operació de les mateixes, ja que prenen en consideració els paràmetres establerts pel fabricant, com ara són: taxes de càrrega/descàrrega, tensió màxima de càrrega, temperatures d'operació, etc.
[EN] Two critical aspects in microgrids operation are the control and power management strategies, which are essential for their efficient operation. The adequate application of these strategies allows compensating the power imbalance caused by the discontinuity in the energy generation or changes in the power demand of the microgrid. In this sense, the overall objective of these power management strategies is to keep the power balance between the generation and the demand in the microgrid through the application of different algorithms that fulfill the criteria of stability, protection, smooth transitions and synchronization with the main grid. In the case of small-scale microgrids with a low number of distributed generators and energy storage systems, the centralized control strategies offer a higher level of flexibility to achieve advanced features in the microgrid and for the suitable power sharing between the converters that compose it. This thesis has been focused on centralized power management algorithms of a microgrid working in grid connected mode. These algorithms can be applied to the power converters connected to the DC bus of both hybrid AC/DC and DC microgrids, where the power dispatch is controlled by a central controller which acquires system data through a communication infrastructure and sets the power to be managed by each of the converters under operation. In this thesis, the experimental validation of the power management strategies of the microgrid is presented, from the point of view of the behavior of the power converters, batteries and loads. It is provided with a realistic evaluation under different microgrid operation scenarios. These scenarios were sudden changes of the irradiation, load, state of charge, the maximum power to be exported/imported from/to the microgrid to/from the grid, and the electricity tariff. Additionally, it is proposed a battery energy storage system that keeps the power balance at the DC bus of the microgrid, taking advantage from the renewable energy sources and adjusting the battery energy storage through a suitable charging procedure specified by the manufacturer. The proposed procedure changes the charging parameters of the batteries depending on the microgrid states. Its goal is to extend the service time of batteries and to allow proper energy management in the system.
Salas Puente, RA. (2019). Gestión eficiente de los convertidores de potencia conectados al bus DC de una Microrred híbrida de generación distribuida [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/118658
TESIS

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N'Goran, Arnold. "Contrôle optimal et gestion énergétique d'une station d'énergie autonome par optimisation robuste." Thesis, Université Paris sciences et lettres, 2020. http://www.theses.fr/2020UPSLM050.

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Le contrôle des micro-réseaux électriques repose sur un problème d’optimisation complexe quand il doit tenir compte de la production intermittente et imparfaitement prévisible des sources d’énergie renouvelables, et de la dynamique physique court-terme des solutions de stockage mises en place pour pallier à cette intermittence. Cette thèse veut apporter un éclairage sur la performance pratique comparée des méthodes d’optimisation pour le contrôle, avec la mise en œuvre de différentes stratégies, exactes ou approchées, analytiques ou numériques, déterministes, stochastiques ou robustes
Power microgrid control involves solving a complex optimisation problem when it must deal with the intermittent, poorly forecasted production of renewable energy sources and with the short-term dynamics of the storage devices used to address intermittency issue. This thesis aims to shed light on the compared practical performance of optimization methods in control with the implementation of different strategies, exact or approximated, analytical or numerical, deterministic, stochastic or robust

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Gomes, Isaías da Luz Ramos. "Microrrede no âmbito da energia 4.0 face a incerteza e risco e ao mercado de eletricidade." Doctoral thesis, Universidade de Évora, 2021. http://hdl.handle.net/10174/29789.

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Esta tese incide sobre o tema da gestão e planeamento de operação de uma microrrede no âmbito da Energia 4.0 por parte do novo agente de mercado, dito de agregador da microrrede. O agregador da microrrede tem como objetivo a maximização do lucro esperado, resultante da participação em mercado de eletricidade. A microrrede inclui fontes de produção distribuída, nomeadamente, microturbinas, eólica, fotovoltaica, armazenamento de energia, veículos elétricos, ditas de microfontes, e o uso de energia, dito de carga. O planeamento é fundamental não só para a microrrede ser um sistema sustentável de energia, mas também para a participação de fontes de energia renováveis integradas em microrrede numa matriz energética mais ampla. É necessário face à incerteza e risco e ao mercado de eletricidade a tomada de decisões apoiadas por um sistema de suporte e informação, que constitui o sistema de suporte de gestão da microrrede, que é vital para a sustentabilidade deste agente de mercado. O sistema de suporte de gestão da microrrede em estudo é baseado na formulação de um problema de programação estocástica linear inteira mista que depende do conhecimento dos processos estocásticos que descrevem os parâmetros incertos. Os parâmetros incertos são descritos por um conjunto de cenários plausíveis apropriados à representação dos eventos que ocorrem na microrrede. Atendendo ao elevado grau de incerteza e às limitações computacionais os cenários são reduzidos a um número razoável de cenários representativos. Ainda, o sistema de suporte de gestão da microrrede permite ao agregador da microrrede apresentar propostas de licitação confiáveis ao considerar o risco na tomada de decisão. Por fim, casos de estudo são simulados com intuito de avaliar o desempenho da microrrede e validar a metodologia em que é baseado o sistema de suporte de gestão da microrrede nesta tese; Abstract: Microgrid under the scope of Energy 4.0 facing uncertainty and risk and electricity markets This thesis focuses on the management and operation planning of a microgrid within the scope of Energy 4.0 by the new market agent, said to be the microgrid aggregator. The microgrid aggregator's goal is to maximize the expected profit, resulting from the participation in the electricity market. The microgrid includes sources of distributed production, namely, microturbines, wind, photovoltaic, energy storage, electric vehicles, called micro-sources, and the use of energy, said to be the load. Planning is fundamental not only for the microgrid to be a sustainable energy system but also for the participation of renewable energy sources integrated into the microgrid in a broader energy matrix. It is necessary for the facing of uncertainty and risk and the electricity market to make decisions supported by a support and information system, which constitutes the microgrid support management system, which is vital for the sustainability of this market agent. The microgrid support management system under study is based on the formulation of a mixed-integer linear stochastic programming problem that depends on knowledge of the stochastic processes that describe the uncertain parameters. The uncertain parameters are described by a set of plausible scenarios suitable to represent the events that occur in the microgrid. Given the high degree of uncertainty and the computational limitations, the scenarios are reduced to a reasonable number of representative scenarios. Also, the microgrid support management system allows the microgrid aggregator to present reliable bidding proposals taking into account risk in decision making. Finally, case studies are simulated to assess the performance of the microgrid and validate the methodology on which the microgrid support management system in this thesis is based.

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Nwulu, Mnandi Ikechi. "Optimal energy management of power systems and microgrids incorporating demand response programs." Thesis, University of Pretoria, 2015. http://hdl.handle.net/2263/56097.

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The energy management of today s power system is of utmost importance because of the increasing complexity of today s power system operations. One of the core energy management functions is determining the optimal dispatch of conventional generators whilst minimizing or maximizing some pre-determined objective function which can either be minimizing costs, minimizing emissions or maximizing profit. These problems have been explicitly defined as the Dynamic Economic Emissions Dispatch (DEED) which is concerned with determining the optimal dispatch of generators whilst minimizing costs and minimizing emissions and the Profit Based Dynamic Economic Emissions Dispatch (PBDEED) which determines the optimal dispatch of generators whilst minimizing costs, emissions and maximizing profit. In this thesis, both the DEED and PBDEED are integrated with Demand Response (DR) programs. Integrating DR programs into the DEED and PBDEED problem instead of considering both problems independently is meant to introduce optimality into both the supply side and demand side of the power system. The DR programs used in this work are a Game Theory DR (GTDR) program which is an Incentive Based DR (IB-DR) program and a Time of Use DR (TOU-DR)program which is a Price Based DR (PB-DR) program. A Model Predictive Control (MPC) strategy is further deployed to solve the GTDR-DEED and GTDR-PBDEED models and obtained results show that for GTDR-DEED, MPC yields higher customer energy curtailment when compared to the open loop controller whilst obtained results also show that MPC shows better robustness against uncertainties and disturbances. Finally, the GTDR program is integrated with a microgrid which is powered by conventional generators and Renewable Energy Sources (RES). The microgrid is in the grid connected mode and power can be traded between the main grid and the microgrid. Again, the results obtained from the optimal energy management of the microgrid collaborate results obtained in the main grid and show that integrating demand response programs into the energy management problem are mutually beneficial to utility and consumers alike and can bring about desired demand reduction in the power system.
Thesis (PhD)--University of Pretoria, 2015.
tm2016
Electrical, Electronic and Computer Engineering
PhD
Unrestricted

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Hosseinimehr, Tahoura. "Power Management of Autonomous Microgrids with Distributed Generations and Energy Storage Systems." Thesis, Curtin University, 2017. http://hdl.handle.net/20.500.11937/59086.

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This thesis is mainly focused on the development of reliable power management strategics for islanded IVIGs. The main objectives of the proposed strategics are to provide accurate active and reactive power sharing, maintain system power balance, coordinate energy storage systems with distributed energy resources, enhance lifetime of the batteries by controlling their state of charge, and efficiently employ renewable energy sources such as photovoltaic (PV) systems in the lVIG, etc.

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Zhang, Tan. "Adaptive Energy Storage System Control for Microgrid Stability Enhancement." Digital WPI, 2018. https://digitalcommons.wpi.edu/etd-dissertations/190.

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Microgrids are local power systems of different sizes located inside the distribution systems. Each microgrid contains a group of interconnected loads and distributed energy resources that acts as a single controllable entity with respect to the grid. Their islanding operation capabilities during emergencies improve the resiliency and reliability of the electric energy supply. Due to its low kinetic energy storage capacity, maintaining microgrid stability is challenging under system contingencies and unpredictable power generation from renewable resources. This dissertation highlights the potential benefits of flexibly utilizing the battery energy storage systems to enhance the stability of microgrids. The main contribution of this research consists in the development of a storage converter controller with an additional stability margin that enables it to improve microgrid frequency and voltage regulation as well as its induction motor post-fault speed recovery. This new autonomous control technique is implemented by adaptively setting the converter controller parameters based on its estimated phase-locked loop frequency deviation and terminal voltage magnitude measurement. This work also assists in the microgrid design process by determining the normalized minimum storage converter sizing under a wide range of microgrid motor inertia, loading and fault clearing time with both symmetrical and asymmetrical fault types. This study evaluates the expandability of the proposed control methodologies under an unbalanced meshed microgrid with fault-induced feeder switching and multiple contingencies in addition to random power output from renewable generators. The favorable results demonstrate the robust storage converter controller performance under a dynamic changing microgrid environment.

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Al, Badwawi Rashid Said Mohammed. "Supervisory control and power management of an AC microgrid." Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/28641.

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The thesis examines the design and implementation of a supervisory controller for the energy management of an AC stand-alone microgrid. The microgrid under study consists of a photovoltaic (PV), battery energy storage system (BESS) and auxiliary (micro gas turbine) units connected to a common AC bus and supplies a local load. The BESS unit has to maintain the AC bus voltage and frequency and needs to balance the difference between the intermittent PV power and that consumed by the load. However, the BESS has limited energy capacity and power rating and therefore it is important to implement a supervisory controller that can curtail the PV power to prevent the battery from being overcharged and also to operate the auxiliary unit to prevent the battery from being over discharged. A Fuzzy Logic Controller (FLC) that can be implemented inside the BESS unit is proposed. It monitors the battery power and State of Charge (SOC) and varies the bus frequency accordingly. The variation in the bus frequency serves as a communication means to the PV and auxiliary units. If the frequency is increased above the nominal value, the PV unit starts to curtail its power and if the frequency is decreased, the auxiliary unit starts to generate power. Power curtailment and supplement are proportional to the frequency variation. In order to avoid any need for communication links between the units, the DC/AC inverters of all the units adopt the well-known wireless droop technique. The droop control of the auxiliary unit is implemented in such a way that the unit is floating on the bus and thus it generates power only if the bus frequency is decreased below its nominal value. The main merits of the proposed controller are simplicity and easiness of implementation inside the BESS unit. The effectiveness of the controller in protecting the battery from over-charging/over-discharging has been verified by simulations including a real-time simulation and experimentally. Furthermore, the thesis investigates the effect of sudden shading of a PV and concentrated PV (CPV) on the bus frequency of an AC stand-alone microgrid. It is known that the CPV power can drop drastically, compared to traditional PV, when it is exposed to shading. A simulation model of the CPV in a microgrid has been built and the results are compared to those of the traditional PV. It is found that shading of the CPV has much more stronger effect on the bus frequency.

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Desta, Alemayehu. "Energy Supply and Demand Side Management in Industrial Microgrid Context." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1234/document.

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En raison de l'augmentation des coûts d'énergie et des préoccupations environnementales telles que les empreintes de carbone élevées, les systèmes de la production d'électricité centralisée se restructurent pour profiter des avantages de la production distribuée afin de répondre aux exigences énergétiques toujours croissantes. Les microgrids sont considérés comme une solution possible pour déployer une génération distribuée qui inclut des ressources énergétiques distribuées DERs (Distributed Energy Resources)(e.g, solaire, éolienne, batterie, etc). Dans cette thèse, nous traitons les défis de la gestion d'énergie dans un microgrid industriel où les charges énergétique sont constituées de processus industriels. Notre plan consiste à diviser la gestion de l'énergie du microgrid en deux parties: la production et la demande d’énergie.Du côté de la production d'énergie, les défis incluent la modélisation des générations de puissance et le lissage des fluctuations des DER. Pour modéliser les générations de puissance, nous proposons un modèle basé sur les concepts de service courbé de Network Calculus. En utilisant cet outil mathématique, nous déterminons une quantité minimale de puissance que les DERs peuvent générer; leur agrégation nous donnera une production d'énergie totale dans le microgrid. Après cela, s'il existe un déséquilibre entre la production et la demande d'énergie, nous proposons des stratégies différentes pour minimiser les coûts d'approvisionnement énergétique. Sur la base des données réelles de la consommation d'énergie d'un site industriel situé en France, des économies significatives peuvent être réalisées en adoptant ces stratégies. Dans cette thèse, nous étudions également comment atténuer les effets des fluctuations de puissance des DERs en conjonction avec des systèmes de stockage d'énergie. Pour cela, nous proposons un algorithme de lissage gaussien et nous le comparons avec des algorithmes de lissage trouvés dans l'état de l'art. Nous avons trouvé que l'algorithme proposé utilise de batterie de moins de taille à des fins de lissage par rapport à d'autres algorithmes. À cette fin, nous sommes également intéressés à étudier les effets de la gamme admissible des fluctuations sur les tailles de la batterie.Du côté de la demande, l'objectif est de réduire les coûts de l'énergie grâce aux approches de gestion de la demande DSM (Demand Side Management) telles que Demand Response (DR) et Energy Efficiency. Comme les processus industriels consomment énormément, une petite réduction de la consommation d'énergie en utilisant les approches DSM pourrait se traduire par des économies cruciales. Cette thèse se concentre sur l'approche DR qui peut profiter des prix variables de l'électricité dans le temps pour déplacer les demandes énergétiques des heures de pointe aux heures creuses. Pour atteindre cet objectif, nous comptons sur un modèle basé sur la théorie de file d'attente pour caractériser les comportements temporels (arrivée et départ des tâches) d'un système de fabrication. Après avoir défini les processus d'arrivée et de départ de tâches, une fonction d'utilisation efficace est utilisée pour prédire le comportement de la machine dans un domaine temporel et qui peut afficher son statut (allumé/éteint) à tout moment. En prenant le statut de chaque machine dans une ligne de production comme une entrée, nous proposons également un algorithme de planification DR qui adapte la consommation d'énergie d'une ligne de production aux deux contraintes de puissance disponibles et de taux de production. L'algorithme est codé à l'aide d’une machine d’état fini déterministe (Deterministic Finite State Machine) dans laquelle les transitions d'état se produisent en insérant une tâche à l'entrée du tapis roulant (on peut aussi avoir des transitions sans insertion de taches). Nous définissons des conditions pour l'existence d’un planificateur réalisable et aussi des conditions pour accepter positivement des demandes DRs
Due to increased energy costs and environmental concerns such as elevated carbon footprints, centralized power generation systems are restructuring themselves to reap benefits of distributed generation in order to meet the ever growing energy demands. Microgrids are considered as a possible solution to deploy distributed generation which includes Distributed Energy Resources (DERs) (e.g., solar, wind, battery, etc). In this thesis, we are interested in addressing energy management challenges in an industrial microgrid where energy loads consist of industrial processes. Our plan of attack is to divide the microgrid energy management into supply and demand sides.In supply side, the challenges include modeling of power generations and smoothing out fluctuations of the DERs. To model power generations, we propose amodel based on service curve concepts of Network Calculus (NC). Using this mathematical tool, we determine a minimum amount of power the DERs can generate and aggregating them will give us total power production in the microgrid. After that, if there is an imbalance between energy supply and demand, we put forward different strategies to minimize energy procurement costs. Based on real power consumption data of an industrial site located in France, significant cost savings can be made by adopting the strategies. In this thesis, we also study how to mitigate the effects of power fluctuations of DERs in conjunction with Energy Storage Systems (ESSs). For this purpose, we propose a Gaussian-based smoothing algorithm and compare it with state-of-the-art smoothing algorithms. We found out that the proposed algorithm uses less battery size for smoothing purposes when compared to other algorithms. To this end, we are also interested in investigating effects of allowable range of fluctuations on battery sizes.In demand side, the aim is to reduce energy costs through Demand Side Management (DSM) approaches such as Demand Response (DR) and Energy Efficiency (EE). As industrial processes are power-hungry consumers, a small power consumption reduction using the DSM approaches could translate into crucial savings. This thesis focuses on DR approach that can leverage time varying electricity prices to move energy demands from peak to off-peak hours. To attain this goal, we rely on a queuing theory-based model to characterize temporal behaviors (arrival and departure of jobs) of a manufacturing system. After defining job arrival and departure processes, an effective utilization function is used to predict workstation’s (or machine’s) behavior in temporal domain that can show its status (working or idle) at any time. Taking the status of every machine in a production line as an input, we also propose a DR scheduling algorithm that adapts power consumption of a production line to available power and production rate constraints. The algorithm is coded using Deterministic Finite State Machine (DFSM) in which state transitions happen by inserting a job (or not inserting) at conveyor input. We provide conditions for existence of feasible schedules and conditions to accept DR requests positively.To verify analytical computations on the queuing part, we have enhanced Objective Modular Network Testbed in C++ (OMNET++) discrete event simulator for fitting it to our needs. We modified various libraries in OMNET++ to add machine and conveyor modules. In this thesis, we also setup a testbed to experiment with a smart DR protocol called Open Automated Demand Response (OpenADR) that enables energy providers (e.g., utility grid) to ask consumers to reduce their power consumption for a given time. The objective is to explore how to implement our DR scheduling algorithm on top of OpenADR

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Rahman, Md Mustafizur. "Microgrid frequency control using multiple battery energy storage system (BESSs)." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/90856/1/MD%20Mustafizur_Rahman_Thesis.pdf.

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The work is a report of research on using multiple inverters of Battery Energy Storage Systems with angle droop controllers to share real power in an isolated micro grid system consisting of inertia based Distributed Generation units and variable load. The proposed angle droop control method helps to balance the supply and demand in the micro grid autonomous mode through charging and discharging of the Battery Energy Storage Systems while ensuring that the state of charge of the storage devices is within safe operating conditions. The proposed method is also studied for its effectiveness for frequency control. The proposed control system is verified and its performance validated with simulation software MATLAB/SIMULINK.

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Wang, Baochao. "Intelligent control and power flow optimization of microgrid : energy management strategies." Thesis, Compiègne, 2013. http://www.theses.fr/2013COMP2122/document.

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La production intermittente et aléatoire des énergies renouvelables, sources photovoltaïques et éoliennes, est toujours un problème pour leur intégration massive dans le réseau public. L'une des solutions est de grouper des sources renouvelables, des sources traditionnelles, des dispositifs de stockage et des charges locales, et les traiter comme une seule unité dans le réseau public. Il s'agit du concept "micro-réseau". Un micro-réseau a des potentiels pour mieux répondre aux besoins de l'utilisateur final et du réseau public, et il facilite la mise en œuvre de futur smart grid, soit le réseau intelligent.Basé sur un micro-réseau représentatif en zone urbaine et intégré aux bâtiments, cette thèse propose une supervision multicouche, afin d'effectuer une étude systémique en mettant en exergue un verrou scientifique concernant l'implémentation d'une optimisation dans l'exploitation en temps réel.La supervision traite un ensemble d’opérations telles que : l'équilibré des puissances,l'optimisation des coûts énergétiques, utilisation de métadonnées, et échange d'informations avec le réseau intelligent et avec l'utilisateur final. Cette supervision a été validée par des tests expérimentaux. Malgré les incertitudes concernant les prévisions météorologiques, la faisabilité d'implémentation de l'optimisation dans l'exploitation réelle est vérifiée. La supervision proposée est en mesure de gérer efficacement les flux en assurant l'équilibre des puissances dans tous les cas. Néanmoins, la performance d'optimisation est liée aux précisions de prédiction. Ce problème peut être amélioré dans les travaux futurs par la mise à jour des résultats d'optimisation en temps réel
The intermittent and random production of renewable sources, such as photovoltaic and wind turbine, is always a problem for their large-scale integration in the utility grid. One of the solutions is to group renewable sources, traditional sources, storage and local consumption and treat it as a single unit in the utility grid. This is the concept of microgrid. A microgrid has the potentials of better responding both grid and end-user requirement, it facilitate the implementation of future smart grid. Based on a representative microgrid in urban area and integrated in buildings, this thesis proposes a multi-layer supervision, in order to realise a systemic study while particularly attempting to cover the research gap of implementing optimisation in realtimeoperation. The supervision handles together power balancing, energetic cost optimisation, metadata using, and information exchanges from both end-users and the smart grid. The supervision has been validated by experimental tests. The feasibility of implementing optimisation in real-time operation is validated even with uncertainties. The supervision is able to manage efficiently the power flow while maintaining power balancing in any case. Nevertheless, optimization effect relies on prediction precision. This problem can be improved in future works by updating optimization in real-time

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de, Azevedo Ricardo. "Fully Decentralized Multi-Agent System for Optimal Microgrid Control." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2461.

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In preparation for the influx of renewable energy sources that will be added to the electrical system, flexible and adaptable control schemes are necessary to accommodate the changing infrastructure. Microgrids have been gaining much attention as the main solution to the challenges of distributed and intermittent generation, but due to their low inertia, they need fast-acting control systems in order to maintain stability. Multi-Agent Systems have been proposed as dynamic control and communication frameworks. Decentralized arrangements of agents can provide resiliency and the much-desired “plug and play” behavior. This thesis describes a control system that implements droop control and the diffusion communication scheme without the need of a centralized controller to coordinate the Microgrid agents to maintain the frequency and stable operating conditions of the system. Moreover, the inter-agent communication is unaffected by changing network configurations and can achieve optimal economic dispatch through distributed optimization.

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Williams, Jada Bennette. "Strategies for Improved Microgrid System Selection for the Electrification of Rural Areas." University of Dayton / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1437961472.

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Hashemi, Farzad Tabassom. "Life Cycle Assessment (LCA) for a DC-microgrid energy system in Fjärås." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263173.

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Application of Photovoltaic PV panels for electricity production has rapidly increased in recent years in Sweden after launching a capital subsidy for PV panel installations in 2009. Kungsbacka municipality’s housing company equipped two groups of buildings in Fjärås with PV systems to generate electricity. The newly built residential buildings are connected to a DC-microgrid, whereas the existing buildings have been equipped with a single PV system. This project conducts a cradle to gate life cycle assessment (LCA) for this DC-microgrid energy system. The main purpose of this project is to determine which parts and processes of the DC-microgrid contribute to highest environmental impact throughout their lifespan from cradle to gate stages. Moreover, this study explores the energy payback time (EPBT) and the cumulative energy demand (CED) for the DC-microgrid. Additionally, this study performs two comparative LCA. First the DC-microgrid is being compared with PV system to determine which system has higher environment impacts, and secondly, the DC-microgrid is being compared with the average electricity mix in Sweden in terms of contribution to environmental impacts. The LCA follows the ISO 14040 framework and the baseline method is applied in order to assess 11 environmental impact categories. Two different functional units are adopted in this study. One is based on installed kilowatt peak (kWp) capacity by which environmental impacts of the PV system are compared with the DC-microgrid system. The other functional unit for this study is 1 kWh of delivered electricity to residential buildings produced by the DC-microgrid system. This functional unit is used exclusively for a stand-alone analysis of the DC-microgrid system in order to make it comparable with other microgrid systems or other systems with different energy sources, such as hydro, wind or nuclear. The results of the stand-alone LCA analysis of the DC-microgrid show that the battery has high contribution in human toxicity and terrestrial ecotoxicity whereas the energy hub system (Ehub) is the main contributor to eutrophication, abiotic depletion, fresh water aquatic ecotoxicity and marineaquatic ecotoxicity. The monocrystalline PV panel has the highest impact on global warming and abiotic depletion (fossil fuel). In addition, the EPBT for the DC-microgrid system is approximately 3.7 years. This means that one can get energy free of cost for an estimated time of 26.5 years if the lifetime of the system is assumed to be 30 years. The CED results show that monocrystalline PV production is an intense energy process which requires more non-renewable energy than all remaining parts of the DC-microgrid. The comparison of the DC-microgrid with the PV system reveals that the DC-microgrid has a higher environmental impact almost in all impact categories. This is mainly due to batteries and inverters which have a clear effect on the result. The CED analysis results illustrate that the multicrystalline PV panel production from the PV system is the most energy demanding process in both categories of renewable and non-renewable energy source. Moreover, the analysis illustrates that the DC-microgrid has still higher environmental impacts in all impact categories compared to the average electricity mix in Sweden. This is due to the electricity production in Sweden relies on hydropower and nuclear power with around 83 % of the total electricity production in the year 2017 which causes a lower environmental burden. Although the DC microgrid system shows a higher environmental impact compared to PV system, it is still a proper option to generate electricity since DC-microgrid system allows to achieve some indirect advantages such as energy saving due to an increase in own usage rate and self-sufficiency rate compared to the PV system. It should be noted that the end-of-life procedures becomes very important especially when crediting back for the recycling of materials. The collection and recycling of the PV panels at their end-of-life should be considered for future work as soon as reliable data are available.
Användningen av solpaneler har de senaste åren kommit att öka markant i Sverige. Ökningen beror på det statliga bidraget för installation av solceller som lanserades 2009. Kungsbacka kommun installerade solcellssystem i två olika typer av byggnader, ny och äldre befintlig byggnad. Den nya byggnaden anslöts till direkt mikronät (DC-mikcrogrid) och den äldre byggnaden utrustades med solcellssystem. Detta projekt utför en ’från vaggan till porten’ livscykelanalys (LCA) för energisystemet direkt mikronät. Syftet är i huvudsak att fastställa vilka delar och processer av det direkta mikronätet som bidrar till störst miljöpåverkan genom dess livslängd, det vill säga från vaggan till porten. Vidare undersöker studien återbetalningstiden (Energy PayBack Time, EPBT) och den ackumulerade energianvändningen (Cumulative Energy Demand, CED) för det direkta mikronätet. Studien utför två komparativa LCA varpå det direkta mikronätet först jämförs med solcellssystemet i syfte att fastställa vilket av systemen har större miljöpåverkan. Studien ämnar också jämföra det direkta mikronätet med den genomsnittliga energimixen i Sverige, också avseende miljöpåverkan. LCA metoden följer ISO 14040-ramverket. Studien är baserad på två funktionella enheter vilka består av installerad kilowatt peak (kWp) kapacitet vilken används för att jämföra solcellssystemet och det direkta mikromåttet. Den andra funktionella enheten är 1 kWh levererad elektricitet till bostäder som producerats genom det direkta mikronätet. Denna funktionella enhet används för en ’stand-alone’ analys av det direkta mikronätet i syfte att göra det jämförbart med andra mikrosystem eller system med olika energikällor så som vatten-, vind- och kärnkraft. Resultaten från ‘stand-alone’ livscykelanalysen av det direkta mikronätet visar på att batteriet har en större effekt på mänsklig toxicitet terrestrisk ekotoxicitet, varpå systemet för energihubb bidrar främst till övergödning, abiotisk utarmning, vattenlevande ekotoxicitet och havslevande ekotoxicitet. Monokristallin solpanel har större påverkan på global uppvärmning och övergödning (fossilabränslen). I övrigt är EPBT för det direkta mikronätet cirka 3,7 år vilket innebär att energin beräknas kostnadsfri i cirka 26,5 år, givet att det kan antas att systemets livslängd är 30 år. CED-resultat visar på att microkristallin solpanel är en intensiv energiprocess som kräver mer icke-förnybar energi jämfört med resterande delar av det direkta mikronätet. Jämförelsen mellan det direkta mikronätet och solcellssystemet visar på att det direkta mikronätet har större miljöpåverkan i de flesta kategorier. Detta beror i huvudsak på batterier och växelriktare som har tydlig effekt på resultatet. Av resultatet från CED-analysen framgår att produktion av multikristallin solpanel av solcellssystemet är det mest energikrävande processen i båda kategorierna för förnybar och icke-förnybar energikälla. Vidare framgår av analysen att det direkta mikronätet har en större miljöpåverkan i alla kategorier, jämfört med påverkan från genomsnittet av energimixen i Sverige. Detta beror på att elproduktionen i Sverige mestadels består av vatten- och kärnkraft som tillsammans 2017 utgjorde 83 procent av den totala energiproduktionen. Denna produktion orsakaren mindre miljöbelastning. Trots att det direkta mikronätet påvisar en högre miljöpåverkan än solcellssystemet, är det fortfarande ett alternativ till att generera elektricitet eftersom det direkta mikronätet bidrar till indirekta fördelar såsom energibesparing. Energibesparingen i det direkta mikronnätet sker således genom ökad användning av den egenproducerade energin samt självförsörjning. Det ska vidare tilläggas att ’end-of-life’ procedurerna blir viktiga i synnerhet när de återvunna materialet återanvänds. Vidare bör solpaneler återanvändas vid ’end-of-life’ vilket bör finnas i åtanke för vidarestudier och i samband med att data tillgängliggörs.

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Alvez, Cristian Adolfo. "Seleção e operação ótima de recursos energéticos distribuídos inseridos em uma microrrede de energia elétrica." Universidade Estadual do Oeste do Parana, 2015. http://tede.unioeste.br:8080/tede/handle/tede/1081.

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Made available in DSpace on 2017-07-10T17:11:49Z (GMT). No. of bitstreams: 1 2015 - Cristian Adolfo Alvez2.pdf: 870298 bytes, checksum: e905359b074a87b04a67ea5befb19f4c (MD5) Previous issue date: 2015-03-13
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The microgrids may be considered as small power systems that operate autonomously and automatically, using technologies linked to it known as distributed energy resources (DERs), being demand, one of this resources. These networks are characterized by intensive use of information, communication and automation technologies, allowing meet demand in form efficient and optimally. However, implement, expand and operate a microgrid brings various economic, technical and operational challenges that must be faced, being one of those challenges the selection and operation of DERs. Thus, this work presents an optimization model, with the objective of analyzing the impact of input parameters on the behavior of the variables involved in selection and operations of these resources. The uncertainties in demand and renewable resources were treated through a scenario tree while for risk estimation was used the value at risk (VaR). The mathematical formulation constitutes a mixed integer linear programming model that was implemented in GAMS language and solved by CPLEX solver. Through simulations was possible to observe the economic benefits that can be obtained through use of DERs, highlight the impact that can produce the intermittent nature of renewable resources on operating costs, and also evidence the importance to have information regards of risk in situations of uncertainty. The results of the simulations show the tool's features developed as an aid when decisions must be made regarding the deployment of DERs and the optimized energy management in a microgrid. As features to highlight, this model operates independently of the energy consumer profile and also allows to perform various analyzes with respect to the influence of the input parameters on the decision variables.
As microrredes podem ser consideradas como pequenos sistemas de potência que operam de maneira autônoma e automática, utilizando tecnologias, conectadas a elas, conhecidas como recursos energéticos distribuídos (REDs), sendo a própria demanda um desses recursos. Estas redes se caracterizam pelo uso intensivo de tecnologias de informação, comunicação e automação, permitindo atender a demanda de forma eficiente e otimizada. No entanto, implementar, expandir e operar uma microrrede traz consigo vários desafios econômicos, técnicos e operacionais que devem ser enfrentados, sendo um deles a seleção e operação dos REDs. Como consequência disso, neste trabalho apresenta-se um modelo de otimização para a seleção e operação de REDs, com o objetivo de analisar o impacto que provocam os diversos parâmetros de entrada no comportamento das variáveis envolvidas na seleção e modo de operação desses REDs. As incertezas na demanda e nos recursos renováveis foram tratadas através de uma arvore de cenários enquanto que para a estimação do risco se utilizou o valor em risco (VaR). A formulação matemática resultante se constitui em um modelo de programação linear inteira mista que foi implementado na linguagem GAMS e resolvido com o solver CPLEX. Através dos resultados de simulação foi possível observar os benefícios econômicos que podem obter-se mediante a utilização de REDs, assim como destacar o impacto que pode produzir a natureza intermitente dos recursos renováveis sobre os custos de operação e também evidenciar a importância de dispor informação do risco em situações de incerteza. Os resultados obtidos corroboram as funcionalidades da ferramenta desenvolvida como auxilio no momento de tomar decisões em relação à implantação de REDs e à gestão otimizada de energia em uma microrrede. Como característica a destacar do modelo, este opera independentemente do qual seja o tipo de demanda do consumidor e permite efetuar diversas análises a respeito da influencia dos parâmetros de entrada sobre as variáveis de decisão.

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Constante, Flores Gonzalo Esteban. "Conservation Voltage Reduction of Active Distribution Systems with Networked Microgrids." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531861356445195.

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Subinas, Seco de Herrera Jose Manuel <1985&gt. "Development of a microgrid with renewable energy sources and electrochemical storage system integration." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6923/.

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Beside the traditional paradigm of "centralized" power generation, a new concept of "distributed" generation is emerging, in which the same user becomes pro-sumer. During this transition, the Energy Storage Systems (ESS) can provide multiple services and features, which are necessary for a higher quality of the electrical system and for the optimization of non-programmable Renewable Energy Source (RES) power plants. A ESS prototype was designed, developed and integrated into a renewable energy production system in order to create a smart microgrid and consequently manage in an efficient and intelligent way the energy flow as a function of the power demand. The produced energy can be introduced into the grid, supplied to the load directly or stored in batteries. The microgrid is composed by a 7 kW wind turbine (WT) and a 17 kW photovoltaic (PV) plant are part of. The load is given by electrical utilities of a cheese factory. The ESS is composed by the following two subsystems, a Battery Energy Storage System (BESS) and a Power Control System (PCS). With the aim of sizing the ESS, a Remote Grid Analyzer (RGA) was designed, realized and connected to the wind turbine, photovoltaic plant and the switchboard. Afterwards, different electrochemical storage technologies were studied, and taking into account the load requirements present in the cheese factory, the most suitable solution was identified in the high temperatures salt Na-NiCl2 battery technology. The data acquisition from all electrical utilities provided a detailed load analysis, indicating the optimal storage size equal to a 30 kW battery system. Moreover a container was designed and realized to locate the BESS and PCS, meeting all the requirements and safety conditions. Furthermore, a smart control system was implemented in order to handle the different applications of the ESS, such as peak shaving or load levelling.

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Osborn, Christopher Eric. "Protection, Automation, and Frequency Stability Analysis of a Laboratory Microgrid System." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1828.

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Due to increasing changes in the power industry, Cal Poly San Luis Obispo's electrical engineering department introduced a set of initiatives to adequately equip students with the skills and knowledge to interact with new technologies. Specifically, the department proposed a microgrid and power systems protection and automation laboratory to strengthen students' knowledge of microprocessor-based relays. This paper outlines a microgrid laboratory system that fulfills the initiative's goal and proposes a collection of laboratory experiments for inclusion in a new laboratory course at Cal Poly. The experiments provide students with practical experience using Schweitzer Engineering Laboratory (SEL) relays and teach fundamental concepts in semi-automated generator synchronization and power system data acquisition. The microgrid laboratory system utilizes SEL relays and a centralized SEL controller to automate frequency regulation through load shedding, power factor correction, generator and utility synchronization, and relay protection group switching.

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Baniasadi, Ali. "Application of heat pumps and thermal storage systems for improved control and performance of microgrids." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2020. https://ro.ecu.edu.au/theses/2316.

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The high penetration of renewable energy sources (RES), in particular, the rooftop photovoltaic (PV) systems in power systems, causes rapid ramps in power generation to supply load during peak-load periods. Residential and commercial buildings have considerable potential for providing load exibility by exploiting energy-e_cient devices like ground source heat pump (GSHP). The proper integration of PV systems with the GSHP could reduce power demand from demand-side. This research provides a practical attempt to integrate PV systems and GSHPs e_ectively into buildings and the grid. The multi-directional approach in this work requires an optimal control strategy to reduce energy cost and provide an opportunity for power trade-o_ or feed-in in the electricity market. In this study, some optimal control models are developed to overcome both the operational and technical constraints of demand-side management (DSM) and for optimum integration of RES. This research focuses on the development of an optimal real-time thermal energy management system for smart homes to respond to DR for peak-load shifting. The intention is to manage the operation of a GSHP to produce the desired amount of thermal energy by controlling the volume and temperature of the stored water in the thermal energy storage (TES) while optimising the operation of the heat distributors to control indoor temperature. This thesis proposes a new framework for optimal sizing design and real-time operation of energy storage systems in a residential building equipped with a PV system, heat pump (HP), and thermal and electrical energy storage systems. The results of this research demonstrate to rooftop PV system owners that investment in combined TSS and battery can be more profitable as this system can minimise life cycle costs. This thesis also presents an analysis of the potential impact of residential HP systems into reserve capacity market. This research presents a business aggregate model for controlling residential HPs (RHPs) of a group of houses that energy aggregators can utilise to earn capacity credits. A control strategy is proposed based on a dynamic aggregate RHPs coupled with TES model and predicting trading intervals capacity requirements through forecasting demand and non-scheduled generation. RHPs coupled with TES are optimised to provide DSM reserve capacity. A rebound effect reduction method is proposed that reduces the peak rebound RHPs power.

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Волчан, Дмитро Вячеславович. "Система управління мережею MicroGrid." Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/39369.

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Мета роботи: підвищити ефективність управління мережею Microgrid за рахунок вдосконалення системи управління електроенергією сонячних батарей для роботи в режимі реального часу. В даній роботі наведено огляд розумних електромереж, їх роль та взаємодія з існуючими електромережами. Розглядаються різні методи та системи управління мережами MicroGrid, проводиться їх аналіз, характеристика та порівняння, надається характеристика основних рівнів керування мережею MicroGrid. Надається аналіз основних переваг управління сонячною енергією відносно інших джерел енергії в мережі MicroGrid. Досліджується алгоритм визначення положення сонця та враховується вплив погодних умов в реальному часі. Показано, що даний метод підвищує ефективність системи накопичення енергії порівняно з традиційними системами управління енергією.
Goal: improve the efficiency of Microgrid network management by improving the solar power management system for real time operation. This paper provides an overview of smart grids, their role and interaction with existing grids. It discusses the various methods and systems for managing the MicroGrid network, analyzes, characterizes, and compares them, and describes the main layers of MicroGrid network management. The main advantages of solar energy management over other sources of energy in the MicroGrid network are analyzed. The algorithm for determining the position of the sun is investigated and the influence of real-time weather conditions is taken into account. It is shown that this method increases the efficiency of the energy storage system in comparison with traditional energy management systems.

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Faqiry, Mohammad. "Efficient double auction mechanisms in the energy grid with connected and islanded microgrids." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35480.

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Doctor of Philosophy
Department of Electrical and Computer Engineering
Sanjoy Das
The future energy grid is expected to operate in a decentralized fashion as a network of autonomous microgrids that are coordinated by a Distribution System Operator (DSO), which should allocate energy to them in an efficient manner. Each microgrid operating in either islanded or grid-connected mode may be considered to manage its own resources. This can take place through auctions with individual units of the microgrid as the agents. This research proposes efficient auction mechanisms for the energy grid, with is-landed and connected microgrids. The microgrid level auction is carried out by means of an intermediate agent called an aggregator. The individual consumer and producer units are modeled as selfish agents. With the microgrid in islanded mode, two aggregator-level auction classes are analyzed: (i) price-heterogeneous, and (ii) price homogeneous. Under the price heterogeneity paradigm, this research extends earlier work on the well-known, single-sided Kelly mechanism to double auctions. As in Kelly auctions, the proposed algorithm implements the bidding without using any agent level private infor-mation (i.e. generation capacity and utility functions). The proposed auction is shown to be an efficient mechanism that maximizes the social welfare, i.e. the sum of the utilities of all the agents. Furthermore, the research considers the situation where a subset of agents act as a coalition to redistribute the allocated energy and price using any other specific fairness criterion. The price homogeneous double auction algorithm proposed in this research ad-dresses the problem of price-anticipation, where each agent tries to influence the equilibri-um price of energy by placing strategic bids. As a result of this behavior, the auction’s efficiency is lowered. This research proposes a novel approach that is implemented by the aggregator, called virtual bidding, where the efficiency can be asymptotically maximized, even in the presence of price anticipatory bidders. Next, an auction mechanism for the energy grid, with multiple connected mi-crogrids is considered. A globally efficient bi-level auction algorithm is proposed. At the upper-level, the algorithm takes into account physical grid constraints in allocating energy to the microgrids. It is implemented by the DSO as a linear objective quadratic constraint problem that allows price heterogeneity across the aggregators. In parallel, each aggrega-tor implements its own lower-level price homogeneous auction with virtual bidding. The research concludes with a preliminary study on extending the DSO level auc-tion to multi-period day-ahead scheduling. It takes into account storage units and conven-tional generators that are present in the grid by formulating the auction as a mixed inte-ger linear programming problem.

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Pulcherio, Mariana Costa. "ROBUST STABILITY ANALYSIS AND DESIGN FOR MICROGRID SYSTEMS." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531727664229489.

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Arcos, Avilés Diego Gustavo. "Energy management strategies based on fuzzy logic control for grid-tied domestic electro-thermal microgrid." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/396164.

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The environmental and economic benefits related to the reduction of both carbon dioxide emission and transmission losses have made distributed renewable generation systems became a competitive solution for future power systems. In this context, Microgrids (MG) are considered as the key building blocks of smart grids and have aroused great attention in the last decade for their potential and the impact they may have in the coming future. The MG concept has captured great attention in the last years since it can be considered one of the most suitable alternatives for integration of distributed generation units in the utility grid. However, this integration involves some challenges to deal with especially when penetration of Renewable Energy Sources (RES) into the distribution network is increased. Therefore, an effective Energy Management System (EMS) is required to ensure optimal energy utilization within the MG, consequently, facilitating both the grid integration and operator control. In this regard, the EMS strategy design depends on the application, MG power architecture, and the power management capability of the MG elements. This dissertation research focuses on the design of different EMS strategies based on Fuzzy Logic Control (FLC) for a residential grid-connected electro-thermal MG including renewable power generation (i.e. photovoltaic and wind turbine generators) and storage capability (i.e. battery bank and water storage tank). The main goal of the FLC-based EMS strategies is to minimize the grid power fluctuations while keeping the battery State-of-Charge (SOC) within secure limits. In order to accomplish this goal, the controller design parameters, such as membership functions and rule-base, of the FLC-based EMS strategies, are adjusted to optimize a pre-defined set of quality criteria of the MG behavior. The analysis and design of the FLC-based EMS strategies for electrical and electro-thermal MG power architectures are developed considering two different scenarios. A first scenario where the MG power forecasting is not provided and a second scenario where the forecast of generation power and load demand are considered. A comparison with the different EMS strategies is presented in simulation level, whereas the features of the enhanced FLC-based EMS strategies are experimentally tested on a real residential microgrid implemented at the Public University of Navarre (UPNa)
Este estudio presenta el diseño de diferentes estrategias de gestión energética basadas en un controlador difuso para una microrred electro-térmica residencial conectada a la red eléctrica compuesta por generadores de energía renovable (solar y eólico) y elementos de almacenamiento de energía (banco de baterías y tanque de almacenamiento de agua). El objetivo principal de las estrategias de gestión es reducir los picos y fluctuaciones de potencia en el perfil de potencia intercambiado con la red eléctrica y preservar la vida útil del sistema de almacenamiento. Se presenta una revisión del estado del arte de estudios anteriores que buscan este objetivo. Se muestra el análisis de dos arquitecturas de microrred. La primera arquitectura consiste en una microrred eléctrica compuesta fuentes de energía renovables, sistema de almacenamiento de energía y el consumo eléctrico de una vivienda. La segunda arquitectura consiste en una microrred electro-térmica que contiene los elementos de la microrred eléctrica e incluye adicionalmente generadores térmicos y el consumo térmico de la vivienda. Con el objetivo de medir la eficiencia de las diferentes estrategias de gestión, se presenta un conjunto de criterios de evaluación que analizan la calidad del perfil de potencia intercambiado con la red eléctrica obtenido mediante las diferentes estrategias de gestión energética. Estos criterios de calidad son utilizados adicionalmente para la optimización de parámetros de los controladores difusos, lo cual se realiza mediante un proceso de aprendizaje fuera de línea que considera los datos históricos del comportamiento de la microrred. La comparación entre las diferentes estrategias de gestión energética se realiza mediante simulación, utilizando los datos reales de generación y consumo adquiridos en la Universidad Pública de Navarra durante el período comprendido entre Julio 2013 y Julio 2014. El diseño de las estrategias de gestión energética para la arquitectura de microrred eléctrica supone dos posibles escenarios, el primer escenario no considera la previsión de consumo y generación de la microrred, y el segundo escenario si considera esta previsión. Las prestaciones de las estrategias basadas en control difuso para cada uno de estos escenarios son validadas experimentalmente en condiciones reales en la microrred de la Universidad Pública de Navarra. Finalmente, se presenta el análisis de las estrategias de gestión basadas en control difuso empleadas a la arquitectura de microrred electro-térmica. La comparación, mediante simulación, con otras estrategias de gestión aplicadas a la misma arquitectura ha demostrado el correcto desempeño de las estrategias desarrolladas basadas en control difuso.

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Jamalzadeh, Reza. "Microgrid Optimal Power Flow Based On Generalized Benders Decomposition." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1512743611060712.

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Bengtsson, Tobias, and Håkan Hult. "Combining Solar Energy and UPS Systems." Thesis, KTH, Tillämpad termodynamik och kylteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148042.

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Solar Power and Uninterruptible Power Supply (UPS) are two technologies that are growing rapidly. The demand for solar energy is mainly driven by the trend towards cheaper solar cells, making it economically profitable for a larger range of applications. However, solar power has yet to reach grid parity in many geographical areas, which makes ways to reduce the cost of solar power systems important. This thesis investigates the possibility and potential economic synergies of combining solar power with UPS systems, which have been previously researched only from a purely technical point of view. This thesis instead evaluates the hypothesis that a combined solar and UPS system might save additional costs compared to regular grid-tied systems, even in a stable power grid. The primary reason is that on-line UPS systems rectifies and inverts all electricity, which means that solar energy can be delivered to the DC part of the UPS system instead of an AC grid, avoiding the installation of additional inverters in the solar power system. The study is divided into three parts. The first part is a computer simulation using MATLAB, which has an explorative method and aims to simulate a combined system before experimenting physically with it. The second part consists of experiments on a physical prototype system based on basic UPS and solar power components. The third part is an economical assessment of investment costs and energy balances, comparing two separate systems (UPS and solar power separate) to one combined (UPS & solar power). The results from the prototype system show that adding solar power to an UPS system does not interfere with the UPS functionality in any major way, however for optimal performance some additional integration may be necessary. On the contrary, the additional power terminal that the solar panels constitute, can increase system performance during certain operational conditions. The result of the economic analysis shows that a combined system has potential for both a lower investment cost due to cheaper components and increased energy savings through lower conversion losses. The conclusion from the study is that a combined solar energy and UPS system is technically feasible. Furthermore, a combined system has clear economic advantages over two separate systems. This means that a combined system might be economically profitable even in situations where a separate system is not.
Solenergi och avbrottsfri kraftförsörjning (UPS) är två tekniker som växer snabbt. Efterfrågan på solenergi ökar huvudsakligen på grund av den snabba utvecklingen mot billigare solceller, vilket lett till att solenergi blivit lönsamt i en större mängd applikationer. I många områden är solenergi dock fortfarande inte kostnadsmässigt konkurrenskraftigt jämfört med traditionella energikällor, vilket gör en fortsatt sänkning av kostnaderna för solenergi till en viktig fråga för solenergiindustrin. Detta examensarbete har som syfte att undersöka om det är tekniskt möjligt att kombinera solenergi med UPS-system samt potentialen för ekonomiska synergier med denna kombination. Tidigare forskning inom området har endast undersökt denna kombination från en rent teknisk synvinkel. Detta examensarbete driver istället hypotesen att ett kombinerat solenergi- och UPS-system kan leda till större kostnadsbesparingar jämfört med ett traditionellt nätanslutet solenergisystem, även i ett stabilt elnät som i Sverige. En on-line UPS skyddar en känslig last genom att kontinuerligt likrikta och sedan åter växelrikta inkommande ström för att därmed både isolera lasten från nätet samt höja strömkvalitén. I UPS-systemet finns därmed en likströmsdel dit solpanelerna direkt kan kopplas istället för att skicka den genererade solenergin ut på elnätet. Därmed undviks inköp och installation av sol-växelriktare i solenergisystemet. Studien är uppdelad i tre delar. Första delen är en datorsimulering i MATLAB och syftar till att explorativt undersöka det kombinerade systemet för en optimerad design innan fysiska experiment utförs. Den andra delen av studien utgörs av experiment på ett fysiskt prototypsystem baserat på ett principiellt UPS- och solenergisystem. Den tredje delen av studien är en ekonomisk analys av både investeringskostnader och energibalanser som jämför ett kombinerat system (UPS & sol) med två separata system (UPS & sol separat). Resultaten från prototypsystemet visar att påkopplandet av solceller i en principiell UPS har mycket låg påverkan på UPS-systemets funktionalitet, samt att solcellerna som en extra energikälla under vissa driftförhållanden kan ha en positiv påverkan på UPS-systemet. För optimal prestanda kan dock en viss integration av systemen krävas. Resultatet från den ekonomiska analysen visar att ett kombinerat system har potential att sänka investeringskostnaden genom billigare komponenter. Ett kombinerat system kan även leda till en högre energibesparing jämfört med ett nätanslutet solenergisystem eftersom konverteringsförlusterna i UPS-systemet sjunker i det kombinerade systemet. Slutsatsen av studierna är att ett kombinerat solenergi- och UPS-system är tekniskt möjligt. Dessutom finns betydande ekonomiska synergier med ett kombinerat system. Detta innebär att ett kombinerat system kan vara lönsamt även i fall där ett separat solelsystem inte är det.

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El, Rahi Georges. "Demand-Side Energy Management in the Smart Grid: Games and Prospects." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78266.

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To mitigate the technical challenges faced by the next-generation smart power grid, in this thesis, novel frameworks are developed for optimizing energy management and trading between power companies and grid consumers, who own renewable energy generators and storage units. The proposed frameworks explicitly account for the effect on demand-side energy management of various consumer-centric grid factors such as the stochastic renewable energy forecast, as well as the varying future valuation of stored energy. In addition, a novel approach is proposed to enhance the resilience of consumer-centric energy trading scenarios by analyzing how a power company can encourage its consumers to store energy, in order to supply the grid’s critical loads, in case of an emergency. The developed energy management mechanisms advance novel analytical tools from game theory, to capture the coupled actions and objectives of the grid actors and from the framework of prospect theory (PT), to capture the irrational behavior of consumers when faced with decision uncertainties. The studied PT and game-based solutions, obtained through analytical and algorithmic characterization, provide grid designers with key insights on the main drivers of each actor’s energy management decision. The ensuing results primarily characterize the difference in trading decisions between rational and irrational consumers, and its impact on energy management. The outcomes of this thesis will therefore allow power companies to design consumer-centric energy management programs that support the sustainable and resilient development of the smart grid by continuously matching supply and demand, and providing emergency energy reserves for critical infrastructure.
Master of Science

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Zhao, Huiying. "Regulation and Control of AC Microgrid Systems with Renewable Generation and Battery Energy Storage System." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1536342769000338.

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