Dissertations / Theses: 'Distribution automation system'

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Ding, Fei. "Smart Distribution System Automation: Network Reconfiguration and Energy Management." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1417291114.

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Haj-ahmed, Mohammed A. "Protection and Automation of Microgrids for Flexible Distribution of Energy and Storage Resources." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1430694499.

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Julie, Ferdie Gavin. "Development of an IEC 61850 standard-based automation system for a distribution power network." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/1183.

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Thesis submitted in fulfillment of the requirements for the degree Master of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology The electric power distribution network, an essential section of the electric power system, supplies electrical power to the customer. Automating the distribution network allows for better efficiency, reliability, and level of work through the installation of distribution control systems. Presently, research and development efforts are focused in the area of communication technologies and application of the IEC 61850 protocol to make distribution automation more comprehensive, efficient and affordable. The aim of the thesis is to evaluate the relevance of the IEC61850 standard-based technology in the development and investigation of the distribution automation for a typical underground distribution network through the development of a distribution automation algorithm for fault detection, location, isolation and service restoration and the building of a lab scale test bench Distribution Automation (DA) has been around for many decades and each utility applies its developments for different reasons. Nowadays, due to the advancement in the communication technology, authentic and automatic reconfigurable power system that replies swiftly to instantaneous events is possible. Distribution automation functions do not only supersede legacy devices, but it allows the distribution network to function on another lever. The primary function of a DA system is to enable the devices on the distribution network to be operated and controlled remotely to automatically locate, isolate and reconnect supply during fault conditions. Utilities have become increasingly interested in DA due to the numerous benefits it offers. Operations, maintenance and efficiencies within substations and out on the feeders can be improved by the development of new additional capabilities of DA. Furthermore, the new standard-based technology has advanced further than a traditional Distribution Supervisory and Control Data Acquisition (DSCADA) system. These days the most important components of a DA system include Intelligent Electronic Devices (IEDs). IEDs have evolved through the years and execute various protection related actions, monitoring and control functions and are very promising for improving the operation of the DA systems. The thesis has developed an algorithm for automatic fault detection, location, isolation and system supply restoration using the functions of the IEC61850 standard-based technology. A lab scale system that would meet existing and future requirements for the control and automation of a typical underground distribution system is designed and constructed. The requirement for the lab scale distribution system is to have the ability to clear faults through reliable and fast protection operation, isolate faulted section/s, on the network and restore power to the unaffected parts of the network through automation control operation functions of the IEC61850 standard. Various tests and simulations have been done on the lab scale test bench to prove that the objective of the thesis is achieved. Keywords: IEC61850 Standard, Distribution automation, Distribution automation system, IEDs, Lab scale test bench, Protection, Algorithm for automatic control

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Altin, Mufit. "Fault Detection And Service Restoration In Medium Voltage Distribution System A Thesis Submitted To The Graduate School Of Natural And Applied Sciences Of Middle East Technical University By Mufit Altin In Partial Fulfillment Of The Requirements." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610519/index.pdf.

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This thesis proposes an algorithm and develops a program for fault detection and system restoration in medium voltage distribution systems. In Turkey, TUBITAK-UZAY developed distribution automation system including fault detection and service restoration functions for Bogazici Electricity Distribution Company. By the time, expanding of distribution system with nonstandardized infrastructure (for example more than one circuit breaker in the feeder, mesh and closed loop feeder structure), developed automation system have not properly worked under these unplanned situations. Taking into consideration of previously utilized TUBITAK Distribution Automation System (TUDOSIS), fault isolation algorithm is improved to cope with practical problems as non-standardized infrastructure and selectivity issue in protection system, and the proposed isolation algorithm is simulated. Further system restoration solution for mesh distribution systems is analyzed for distribution system in Turkey and expert system based algorithm is proposed.

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Souto, Laiz de Carvalho. "Fault location in power distribution networks with distributed generation." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-28062016-151847/.

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This research presents the development and implementation of fault location algorithms in power distribution networks with distributed generation units installed along their feeders. The proposed algorithms are capable of locating the fault based on voltage and current signals recorded by intelligent electronic devices installed at the end of the feeder sections, information to compute the loads connected to these feeders and their electric characteristics, and the operating status of the network. In addition, this work presents the study of analytical models of distributed generation and load technologies that could contribute to the performance of the proposed fault location algorithms. The validation of the algorithms was based on computer simulations using network models implemented in ATP, whereas the algorithms were implemented in MATLAB. Esta pesquisa apresenta o desenvolvimento e a implementação de algoritmos para localização de faltas em redes primárias de distribuição de energia elétrica que possuem unidades de geração distribuída conectadas ao longo dos seus alimentadores. Esses algoritmos são capazes de efetuar a localização de faltas utilizando registros dos sinais de tensões e correntes realizados por dispositivos eletrônicos inteligentes, instalados nas saídas dos alimentadores de distribuição, além de informações que permitam determinar os valores das cargas conectadas nesses alimentadores, características elétricas, e o estado operativo da rede de distribuição. Ademais, este trabalho apresenta o estudo de modelos analíticos de unidades de geração distribuída e de cargas que poderiam contribuir positivamente com o desempenho dos algoritmos propostos. A validação dos algoritmos foi realizada através de simulações computacionais, utilizando modelos de rede implementados em ATP e os algoritmos foram implementados em MATLAB.

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Holmqvist, Niclas. "HANDHELD LIDAR ODOMETRY ESTIMATION AND MAPPING SYSTEM." Thesis, Mälardalens högskola, Inbyggda system, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-41137.

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Ego-motion sensors are commonly used for pose estimation in Simultaneous Localization And Mapping (SLAM) algorithms. Inertial Measurement Units (IMUs) are popular sensors but suffer from integration drift over longer time scales. To remedy the drift they are often used in combination with additional sensors, such as a LiDAR. Pose estimation is used when scans, produced by these additional sensors, are being matched. The matching of scans can be computationally heavy as one scan can contain millions of data points. Methods exist to simplify the problem of finding the relative pose between sensor data, such as the Normal Distribution Transform SLAM algorithm. The algorithm separates the point cloud data into a voxelgrid and represent each voxel as a normal distribution, effectively decreasing the amount of data points. Registration is based on a function which converges to a minimum. Sub-optimal conditions can cause the function to converge at a local minimum. To remedy this problem this thesis explores the benefits of combining IMU sensor data to estimate the pose to be used in the NDT SLAM algorithm.

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Haffar, Mohamad. "Développement d'une plateforme de co-simulation en vue de validation et d'évaluation de performances des systèmes de communication pour les installations de distribution électriques." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENT043.

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Un système de distribution électrique est le cœur de tous types de sites industriels, aussi bien les sites producteurs d'énergie que les sites consommateurs. La sécurité de ce système doit être impérativement assurée par la mise en place des unités assurant plusieurs fonctionnalités de protection contre les dédauts électriques. Parmi ces fonctionalités il existe celles qui se basent sur des échanges d'information entre plusieurs unités de protection. Le standard IEC 61850 guarantit cet échange des informations via des signaux ‘temps réel' échangé via le réseau de communication. Vue l'aspet non deterministe de ces signaux, une étude poussée de leur fiabilité doit être effectuée. Pour ces raisons notre travail de thèse a pour objectif de mettre en place une méthodologie, basée sur une plateforme de Co-Simulation conçue pendant notre étude, qui permet la validation de la fiabilité de ces messages tout au long du cycle de vie d'un système de communication IEC 61850 From 2004, a new worldwide standard of communication IEC61850 is introduced in the majority of substation automation system carrying out new innovation prospects to the world of substation. One of these feature is that it allows the exchange of security real time communication messages all over the communication network. These messages are used as control information for the Distributed Automation Application 'DAA'. Taking into consideration that DAA have a direct effect on ythe dependability of a smart grid architecture, the fiability of these real time IEC 61850 should be evaluated. For these reasons, our research delas with the development of a Co-Simulation platform that permits the evaluation and validation of an IEC 61850 communication network

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Yang, Jinsong. "Data Distribution Service for Industrial Automation." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-15483.

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In industrial automation systems, there is usually large volume of data which needs to be delivered to right places at the right time. In addition, large number of nodes in the automation systems are usually distributed which increases the complexity that there needs to be more point-to-point Ethernet-connections in the network. Hence, it is necessary to apply data-centric design and reduce the connection complexity. Data Distributed Service for Real-Time Systems (DDS) is a data-centric middleware specification adopted by Object Management Group (OMG). It uses the Real-Time Publish-Subscribe protocol as its wiring protocol and targets for mission- and business-critical systems. The IEC 61499 Standard defines an open architecture for the next generation of distributed control and automation systems. This thesis presents the structure and key features of DDS and builds a model of real-time distributed system based on the IEC 61499 Standard. Then a performance evaluation of the DDS communication based on this model is carried out. The traditional socket-based communication is also evaluated to act as a reference for the DDS communication. The results of the evaluation mostly show that DDS is considered as a good solution to reduce the complexity of the Ethernet connections in distributed systems and can be applied to some classes of industrial automation systems.

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Kauffmann, Philippe. "Mesure de densité de courant électrique en vue d'améliorer l'automatisation du processus de galvanoplastie industrielle." Angers, 1995. http://www.theses.fr/1995ANGE0017.

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Le travail présenté dans ce mémoire concerne l'amélioration du processus industriel de traitement de surface électrolytique par la mesure de densité de courant électrique ponctuelle dans les bains de galvanisation. La méthode générale adoptée consiste en la mise au point d'un capteur de densité relative, puis l'étude d'un capteur de densité absolue plus performant. On présente enfin l'association des capteurs avec des automates, eux-mêmes intégrés à un système informatique communiquant, généralisé à l'entreprise.

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Bleyle, Derek J. "A secure Web based data collection and distribution system for Global Positioning System research." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1097605631.

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Navaneethan, Senthivadivelu. "Automatic fault location system for low voltage underground distribution networks." Thesis, University of Strathclyde, 2003. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21540.

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This thesis presents a novel approach to automating Time Domain Reflectrometry (TDR) waveform acquisition and automatic TDR based fault location in Low Voltage (450-1000V) Underground Distribution Networks (LVUDNs). First, the types of faults that occur in LVUDN and previously available fault location techniques are discussed and their relative advantages and limitations described. Adaptive Filter theory, Wavelet Transform Theory and Fuzzy Logic are presented. Software is developed to automate: checking of the test lead connections, adjusting the internal balance network to match the cable surge impedance, blown fuse detection and backfeed identification, auto recording and storage of data, and voltage and current triggering for transient faults. Software is also developed for both direct and remote control of the instrument via a standard telephone line, GSM modem or direct serial link. Adaptive and fuzzy based, and wavelet based automatic fault location systems are developed. Both systems pre-process the TDR waveforms by using a simple thresholding technique to identify single phase tees and to locate three phase faults. The adaptive and fuzzy based system uses an adaptive filter to produce a composite waveform from the healthy and faulty TDR waveforms and the fault distance is calculated using the composite waveform. If the result produces more than one possible fault distance either from the TDR waveforms or the error waveforms, the system uses fuzzy reasoning to find a common fault distance. In the wavelet based fault location process the TDR waveforms are split into four multi-scales before applying the adaptive filtering and calculating the fault distance using a selected scale. To improve the accuracy of fault distance calculation, local mean and gradient techniques are used in the adaptive and fuzzy based fault location system and latter technique is used in the wavelet enhanced fault location system. The performances of both systems were tested using data from a cable model and from real LVUDNs and gave an accuracy of ±4.3m of the actual fault distance.

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Bezerra, JosÃ Roberto. "Contributions to the efficient switch placement and automatic restoration of power distribution systems." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16190.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico The demand for electricity grows in the same way as the consumers requirement for an uninterrupted supply. Many reliability indices are applied by regulatory agencies, utilities and consumers for measuring the power systems reliability. The improvement of such indices has been required by regulatory agencies and pursued by energy distributors. Therefore, the application of automatic restauration systems has gained relevance as a support tool for control center operators for a quick and secure restauration of faulty electric networks. This work proposes two contributions to the restoration process of radial power system networks. The former is a multiobjective algorithm for effective switch placement in distribution networks. Multiobjective optimization techniques are applied to achieve a set of non-dominated solutions rather than an unique one. Therefore, the decision making for switch placement is eased by the flexibility given from the multiple solutions. The latter contribution is a model for automatic restoration of power distribution networks adaptable to the network topology changes and able to ensure the operational security of the power system network. The proposed model is based on coloured Petri nets as the modelling tool. Reusability and extensibility features have been pursued and implemented on the proposed model. As a result, the needed time to restore faulty power system networks is reduced without compromising its operational security. Case studies are presented demonstrating the benefits to the power system distribution utilities obtained with the deployment of the proposed tools to improve the reliability of the power system networks. A demanda por energia elÃtrica cresce e de igual modo a exigÃncia dos consumidores pela continuidade do seu fornecimento. Diversos Ãndices de confiabilidade sÃo utilizados por agÃncias reguladoras, concessionÃrias e consumidores para aferir a continuidade dos sistemas elÃtricos de potÃncia. A melhoria de tais Ãndices vem sendo requisitada por agÃncias reguladoras e perseguida pelas concessionÃrias de energia. Para tanto, o uso de sistemas de restauraÃÃo automÃtica vem ganhando destaque como uma ferramenta de apoio a operadores de centros de controle para a restauraÃÃo rÃpida e segura de redes elÃtricas em situaÃÃes de falta. Este trabalho apresenta duas contribuiÃÃes para a restauraÃÃo automÃtica de redes radiais de distribuiÃÃo de energia. A primeira consiste em um algoritmo para o posicionamento eficiente de chaves telecontroladas em redes de distribuiÃÃo. TÃcnicas de otimizaÃÃo multiobjetivo sÃo aplicadas para obter-se como resultado um conjunto de soluÃÃes nÃo-dominadas ao invÃs de uma Ãnica soluÃÃo. Com isso, a tomada de decisÃo para o posicionamento eficiente de chaves na rede elÃtrica Ã facilitado pela flexibilidade das mÃltiplas soluÃÃes oferecidas pelo algoritmo proposto. A segunda contribuiÃÃo do trabalho consiste em um modelo para restauraÃÃo automÃtica da rede de distribuiÃÃo de energia adaptÃvel Ãs mudanÃas de topologia e que garante a seguranÃa operacional da rede elÃtrica. O modelo proposto fundamentou-se em Redes de Petri Coloridas como ferramenta de modelagem. CaracterÃsticas de reusabilidade e extensibilidade foram buscadas e implementadas no modelo proposto. Como resultado, o tempo necessÃrio para restaurar redes elÃtricas em condiÃÃo de falta Ã reduzido sem comprometer a seguranÃa do sistema elÃtrico. Estudos de caso sÃo apresentados evidenciando os benefÃcios para concessionÃrias de distribuiÃÃo de energia com a implementaÃÃo das ferramentas propostas para melhoria da confiabilidade da rede elÃtrica.

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Lenz, Malte, and Johan Rhodin. "Reliability calculations for complex systems." Thesis, Linköpings universitet, Reglerteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69952.

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Functionality for efficient computation of properties of system lifetimes was developed, based on the Mathematica framework. The model of these systems consists of a system structure and the components independent lifetime distributions. The components are assumed to be non-repairable. In this work a very general implementation was created, allowing a large number of lifetime distributions from Mathematica for all the component distributions. All system structures with a monotone increasing structure function can be used. Special effort has been made to compute fast results when using the exponential distribution for component distributions. Standby systems have also been modeled in similar generality. Both warm and cold standby components are supported. During development, a large collection of examples were also used to test functionality and efficiency. A number of these examples are presented. The implementation was evaluated on large real world system examples, and was found to be efficient. New results are presented for standby systems, especially for the case of mixed warm and cold standby components.

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CAMPANER, RICCARDO. "VOLTAGE CONTROL SYSTEMS FOR TRANSMISSION AND DISTRIBUTION GRIDS." Doctoral thesis, Università degli Studi di Trieste, 2017. http://hdl.handle.net/11368/2908145.

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The research activities carried out for the present PhD dissertation concerns the increasingly evident and widespread set of problems related to the remarkable levels of distributed generation (DG) connected to electric networks. It has also included the proposal of applicable and performing control techniques, suitable to allow new connection of Renewable Energy Sources (RES) generators, able to assure adequate reliability and quality of service through the integration of electric networks with Information and Communication Technology (ICT) (process also known with the term “Smart Grid”). The focus of the research activity was directed to voltage control of DG units based on RES, both connected to low voltage (LV) and medium voltage (MV) distribution networks and the ones directly connected to high voltage (HV) transmission system. A short summary of the different chapters provides an overview of the present work: - Chapter 1 describes the architecture of the national electric system, the on-going change from the traditional paradigm of energy production towards the DG model and the problems deriving from such change. To provide an idea of the dimension of the phenomenon some data about DG installed in the latest years both at international and national level are given, together with the results of studies on the economic and energetic advantage of photovoltaic technology carried out in view of a possible assessment of future impacts on energy distribution systems. - Chapter 2 outlines the features of a Smart Grid apt to receive RES generation, at the same time guaranteeing suitable levels of reliability and quality service. The chapter summarizes the European and Italian Regulatory Environment for the connection of DG to distribution networks and electric transmission. - Chapter 3 concentrates on voltage control for DG plants based on RES. The chapter reports a review of the control techniques proposed by literature and by recent connection rules, together with the control techniques collected and proposed by our research group. - Chapter 4 presents the results of the studies carried out on some test electric networks presented in scientific literature and some really existing ones. - Chapter 5 reports some final considerations. - Appendix A1 provides a description of the software tools used to carry out the simulations. More specifically tests have been conducted with the aid of Matlab@ software, the toolbox open source PSAT and DOME software for steady state and dynamic simulations.

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Choi, Sungyun. "Autonomous state estimation and its application to the autonomous operation of the distribution system with distributed generations." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50250.

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The objective of this thesis is to propose guidelines for advanced operation, control, and protection of the restructured distribution system by designing the architecture and functionality for autonomous operation of the distribution system with DGs. The proposed architecture consists of (1) autonomous state estimation and (2) applications that enable autonomous operation; in particular, three applications are discussed: setting-less component protection, instant-by-instant management, and short-term operational planning. Key elements of the proposed approach have been verified: (1) the proposed autonomous state estimation has been experimentally tested using laboratory test systems and (2) the feasibility of the setting-less component protection has been tested with numerical simulations.

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Fehr, Ralph E. "An integrated optimal design method for utility power distribution systems." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001356.

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Isapour, Chehardeh Maziar. "AUTOMATIC RECONFIGURATION OF RADIAL DISTRIBUTION NETWORK FOR RELIABILITY ASSESSMENT USING THE CIRCUIT GRAPH." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/dissertations/1572.

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The problem of optimum restoration after occurrence the outages in a distribution network is an important issue in smart grids. In this kind of networks remote-controlled switches, alternative sources and grid-connected distributed generators (DG) are employed. Therefore, the reliability of the system (corresponding to the frequency of failures and the duration of interruptions) is improved by operating the switches to resupply a part of interrupted system during the repair time. To evaluate the reliability indices in smart grids, neglecting the restoration during the repair time causes the wrong assessment of the network. Thus, considering the rerouting the power during the interruptions seems necessary to calculate the reliability indices. The problem of restoration is formulated as a non-linear integer programming problem with the assistance of the network graph. The circuit graph method is also used to pre-evaluate the feasible interchanging operations to enhance the efficiency of the computations. The topological and operational constraints in this formulation can be found and resolved with the assistance of fundamental cut-set matrix. The optimum restoration schemes is obtained by considering the optimal islanded mode of operation of the DGs which implies maximizing the loading of DGs while not violating their generation capacities. The optimum restoration policies lead us to find the optimum number and location of those manual switches that should be upgraded to the remote-controlled switches. This is a multi-objective problem that contains the contribution of each restoration policy in the reliability improvement and the cost of those switching operations. The proposed algorithm is applied to different standard test systems and the results are compared to the results obtained from other methods and algorithms.

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Roe, Curtis Aaron. "Impacts of automated residential energy management technology on primary energy source utilization." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45865.

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The objective of the proposed research is to analyze automated residential energy management technology using primary energy source utilization. A residential energy management system (REMS) is an amalgamation of hardware and software that performs residential energy usage monitoring, planning, and control. Primary energy source utilization quantifies power system levels impacts on power generation cost, fuel utilization, and environmental air pollution; based on power system generating constraints and electric load. Automated residential energy management technology performance is quantified through a physically-based REMS simulation. This simulation includes individual appliance operation and accounts for consumer behavior by stochastically varying appliance usage and repeating multiple simulation iterations for each simulated scenario. The effect of the automated REMS under varying levels of control will be considered. Aggregate REMS power system impacts are quantified using primary energy source utilization. This analysis uses a probabilistic economic dispatch algorithm. The economic dispatch algorithm quantifies: fuel usage and subsequent environmental air pollution (EAP) generated; based on power system generating constraints and electric load (no transmission constraints are considered). The analysis will comprehensively explore multiple residential energy management options to achieve demand response. The physically-based REMS simulation will consider the following control options: programmable thermostat, direct load control, smart appliance scheduling, and smart appliance scheduling with a stationary battery. The ability to compare multiple automated residential energy management technology options on an equal basis will guide utility technology investment strategies.

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Barros, Joao Victor Cavalcante. "Sistema multiagente para recomposiÃÃo automÃtica de subestaÃÃo e redes de distribuiÃÃo de energia elÃtrica." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11305.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico Este trabalho apresenta um sistema multiagente para recomposiÃÃo au-tomÃtica de redes de distribuiÃÃo de energia elÃtrica. O sistema proposto Ã formado por trÃs tipos de agentes: agente dispositivo, agente alimentador e agente subesta-ÃÃo. Os agentes dispositivos estÃo associados aos equipamentos do sistema e sÃo responsÃveis pela coleta de informaÃÃes da rede; os agentes alimentadores sÃo responsÃveis pelo gerenciamento dos alimentadores do sistema; e, os agentes su-bestaÃÃes sÃo responsÃveis pelo gerenciamento da capacidade de suprimento da rede. SÃo apresentados os comportamentos e interaÃÃes dos agentes do sistema durante o processo de recomposiÃÃo, visando restabelecer a energia elÃtrica dos trechos desenergizados e nÃo defeituosos, afetados por falta no alimentador ou falta no transformador da subestaÃÃo. SÃo apresentados oito estudos de casos que testam diferentes situaÃÃes possÃveis de ser encontrada nos sistemas de distribuiÃÃo, como recomposiÃÃo mediante descoordenaÃÃo da proteÃÃo, recomposiÃÃo parcial do sistema devido as restriÃÃes operacionais do sistema e recomposiÃÃes para falta no transformador da subestaÃÃo. Para validaÃÃo dos casos testes foi desenvolvido um simulador que possibilita a simulaÃÃo de faltas em diferentes locais do sistema elÃtrico em estudo. AtravÃs do ambiente visual do simulador, onde Ã disponibilizado o diagrama unifilar do sistema com os estados dos equipamentos e a ferramenta de captura de mensagem do JADE, Ã possÃvel simular diversos cenÃrios e observar interaÃÃo dos agentes em busca da recomposiÃÃo do sistema. O sistema proposto Ã capaz de localizar a falta, isolar o trecho defeituoso e restaurar o sistema, considerando restriÃÃes operacionais e descoordenaÃÃo do sistema de proteÃÃo. This work presents a multi-agent system for automatic restoration of power distribution networks. The proposed system consists of three types of agents: device agent, feeder agent and substation agent. Device agents are associated with system equipment and are responsible for information acquisition of the network; the feeder agents are responsible to manage the feeders; and the substations agents are accountable of manage the network supply capability. The behaviors and interactions of the system agents during the restoration process, aiming to restore the feeder sectors affected by but not in fault, are presented. Eight case studies are presented, which test different possible situations likely to be found in the distribution systems, such as restoration by uncoordinated protection, partial recovery of the system because of operating system restrictions and recomposition for faults in the transformer substation. To validate the test cases a simulator was developed, which allows the simulation of faults in different locations of the power system under study. Through the simulator, where there are the single line diagram of the system with the state of the equipment and the tool to capture message in JADE, is possible to simulate different scenarios and observe the interaction of agents in search of system restoration. The proposed system is able to locate and isolate the fault, and restore suitably the system, considering operating limits and uncoordinated system protection.

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Melo, Lucas Silveira. "Development of a platform for implementing multi-agents systems for application to automatic restoration of electric power distribution systems." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=15234.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico It is common the occurence of permanent faults in power distribution systems. In a typical radial power distribution system when the fault protection system operates, may cause power-off not only in the fault section, but also to all customers downstream the fault.Through disjunction devices normally closed along the feeder, and normaly open on its edges, is possible to isolate the faulty sector and reenergize the healthy ones, reducing the number of customers affected by a fault. Network operators normally do this procedure manually and in addition to demand a considerable ammount of time, is subject to errors on the part of the operator. In order to automate the analisys of the network and provided it of self-healing capacity, various methods have been proposed to solve this matter. Most of these approaches adopts a centralized strategy and do not address the aspect of electric power grid self-healing. In this work is proposed an approach that uses multi-agent systems for self-healing purposes of power distribution systems. Multi-agent are highly suitable for modelling distributed systems in the smart grid domain. For a safe recovery and without violation of operational restrictions the feeder agents perform an evaluation before device agents send any command to the network switches. The proposed multi-agent system is implemented in a agentâs development platform proposed in this work that uses the Python programming language. The platform is called PADE, Python Agent DEvelpment framework. The computer representation of the network, without simplifications, is accomplished by a data encoding based on the theory of graphs and named node-depth representation that serves as a basis for the development of an API of network representation that models each of the required components in the restoration analysis. The device agents communicate with IED that in turn control the switches in the network, by means of IEC 61850 protocols: GOOSE and MMS. To validate the proposed approach, computer simulations are performed using a simplified distribution power grid as a case study and a test platform with relay test case, protection and control IED, managed switch and embedded systems. Ã comum a ocorrÃncia de faltas permanentes no sistema de distribuiÃÃo de energia elÃtrica. Por tratar-se de um sistema radial, a atuaÃÃo da proteÃÃo para estas faltas causa a desenergizaÃÃo nÃo sÃ do setor em falta, mas de todos os consumidores a jusante do setor onde ocorreu a falta. Fazendo uso dos dispositivos de disjunÃÃo normalmente fechados ao longo do alimentador e normalmente abertos nas suas bordas Ã possÃvel isolar o setor sob falta e re-energizar os setores sÃos, reduzindo o nÃmero de consumidores afetados por um defeito. Este procedimento Ã normalmente feito pelos operadores da rede, e alÃm de demandar um tempo considerÃvel, estÃ sujeito Ã erros por parte do operador. No sentido de tornar automÃtica as anÃlises de restauraÃÃo da rede e prover o sistema da capacidade de auto-cura, tÃm sido propostas diversas metodologias para o problema. A maioria destas abordagens adota uma estratÃgia centralizada e nÃo abordam o aspecto de auto-cura da rede elÃtrica. Neste trabalho, Ã proposta uma abordagem utilizando sistemas multiagentes para recomposiÃÃo de setores de alimentadores de distribuiÃÃo de energia elÃtrica. A tÃcnica de sistemas multiagentes vem se mostrando bastante promissora no desenvolvimento de sistemas distribuÃdos em um contexto de redes elÃtricas inteligentes. Para que a recomposiÃÃo ocorra sem a violaÃÃo das restriÃÃes operacionais e de forma coerente, sÃo feitas anÃlises pelos agentes alimentadores antes que qualquer comando seja enviado para as chaves do sistema por meio de agentes dispositivo. O sistema multiagente proposto Ã implementado em uma plataforma de desenvolvimento de agentes proposta neste trabalho e que utiliza a linguagem de programaÃÃo Python. A plataforma tem o nome de PADE, Python Agent DEvelpment framework. A representaÃÃo computacional sem simplificaÃÃes da rede Ã proporcionada por uma codificaÃÃo de dados apoiada na teoria de grafos e denominada RepresentaÃÃo NÃ-Profundidade, que serve de base para o desenvolvimento de uma API de representaÃÃo da rede-elÃtrica que modela cada um dos componentes necessÃrios nas anÃlises de recomposiÃÃo. Ao agente dispositivo Ã dada a possibilidade de comunicaÃÃo com IED, que controlam as chaves do sistema, por meio dos protocolos da norma IEC 61850: GOOSE e MMS. Para validar a metodologia proposta sÃo realizadas simulaÃÃes computacionais utilizando uma rede de distribuiÃÃo simples como caso base e uma plataforma de testes com: mala de testes de relÃs, IED de proteÃÃo e controle de mercado, switch gerenciÃvel e placas de desenvolvimento de sistemas embarcados.

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FERRO, GIULIO. "Competitive and Cooperative Approaches to the Balancing Market in Distribution Grids." Doctoral thesis, Università degli studi di Genova, 2020. http://hdl.handle.net/11567/1010553.

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The electrical grid has been changing in the last decade due to the presence, at the distribution level, of renewables, distributed generation, storage systems, microgrids, and electric vehicles. The introduction of new legislation and actors in the smart grid’s system opens new challenges for the activities of companies, and the development of new energy management systems, models, and methods. In order to face this revolution, new market structures are being defined as well as new technologies and optimization and control algorithms for the management of distributed resources and the coordination of local users to contribute to active power reserve and ancillary services. One of the main problems for an electricity market operator that also owns the distribution grid is to avoid congestions and maximize the quality of the service provided. The thesis concerns the development and application of new methods for the optimization of network systems (with multi-decision makers) with particular attention to the case of power distribution networks This Ph.D. thesis aims to address the current lack of properly defined market structures for the determination of balancing services in distribution networks. As a first study, to be able to handle the power flow equation in a computationally better way, a new convex relaxation has been proposed. Thereafter, two opposite types of market structure have been developed: competitive and cooperative. The first structure presents a two-tier mechanism where the market operator is in a predominant position compared to other market players. Vice versa in the cooperative mechanism (solved through distributed optimization techniques ) all actors are on the same level and work together for social welfare. The main methodological novelties of the proposed work are to solve complex problems with formally correct and computationally efficient techniques.

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Loeffler, Benjamin Haile. "Modeling and optimization of a thermosiphon for passive thermal management systems." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45960.

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An optimally designed thermosiphon for power electronics cooling is developed. There exists a need for augmented grid assets to facilitate power routing and decrease line losses. Power converter augmented transformers (PCATs) are critically limited thermally. Conventional active cooling system pumps and fans will not meet the 30 year life and 99.9% reliability required for grid scale implementation. This approach seeks to develop a single-phase closed-loop thermosiphon to remove heat from power electronics at fluxes on the order of 10 - 15 W/cm2. The passive thermosiphon is inherently a coupled thermal-fluid system. A parametric model and multi-physics design optimization code will be constructed to simulate thermosiphon steady state performance. The model will utilize heat transfer and fluid dynamic correlations from literature. A particle swarm optimization technique will be implemented for its performance with discrete domain problems. Several thermosiphons will be constructed, instrumented, and tested to verify the model and reach an optimal design.

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Cederblad, Gustav. "Finding Synonyms in Medical Texts : Creating a system for automatic synonym extraction from medical texts." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-149643.

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This thesis describes the work of creating an automatic system for identifying synonyms and semantically related words in medical texts. Before this work, as a part of the project E-care@home, medical texts have been classified as either lay or specialized by both a lay annotator and an expert annotator. The lay annotator, in this case, is a person without any medical knowledge, whereas the expert annotator has professional knowledge in medicine. Using these texts made it possible to create co-occurrences matrices from which the related words could be identified. Fifteen medical terms were chosen as system input. The Dice similarity of these words in a context window of ten words around them was calculated. As output, five candidate related terms for each medical term was returned. Only unigrams were considered. The candidate related terms were evaluated using a questionnaire, where 223 healthcare professionals rated the similarity using a scale from one to five. A Fleiss kappa test showed that the agreement among these raters was 0.28, which is a fair agreement. The evaluation further showed that there was a significant correlation between the human ratings and the relatedness score (Dice similarity). That is, words with higher Dice similarity tended to get a higher human rating. However, the Dice similarity interval in which the words got the highest average human rating was 0.35-0.39. This result means that there is much room for improving the system. Further developments of the system should remove the unigram limitation and expand the corpus the provide a more accurate and reliable result.

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Singh, Neeta S. "An automatic code generation tool for partitioned software in distributed computing." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001129.

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Ramde, Sara, and Lana Qadir. "Effektivisering av materialflödet i inlagringsprocessen i ett distributionslager : Genom exkludering av begränsningar." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-41781.

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Syfte – Syftet med studien är att identifiera kritiska begränsningar i inlagringsprocessen i ett distributionslager för att därmed kunna effektivisera materialflödet. Studiens syfte uppnås genom att följande forskningsfrågor har formulerats: Vilka kritiska begränsningar kan förekomma i materialflödet i en inlagringsprocess i ett distributionslager? Hur kan de identifierade begränsningarna exkluderas i en inlagringsprocess? Metod – Studien hade en induktiv ansats och datainsamling skedde genom intervjuer, observationer, dokumentstudier och litteraturstudier. En fallstudie genomfördes på ett distributionslager och empiri och teori har jämförts för att kunna uppfylla studiens syfte. Resultat – Studiens resultat påvisar att de förekommande kritiska begränsningarna i ett distributionslager är brist på yta, materialhantering, automatiska system samt lagerlayout. Studiens slutsats är att begränsningarna är sammankopplade och påverkar varandra eftersom de ingår i samma process. För att exkludera begränsningarna bör distributionslager implementera diverse standarder i sin inlagringsprocess och arbeta med ständiga förbättringar. Implikationer – Studien bidrar inte med nya teorier men bidrar med praktisk nytta för distributionslager med liknande kriterier som studiens fallföretag. Begränsningar – Studien riktar enbart in sig på distributionslager och var en fallstudie av enfallsdesign. Genom att utföra flera liknande undersökningar på företag med liknande kriterier hade generaliserbarheten kunnat stärkas. Purpose – The purpose of the study is to identify critical constraints in the inbound process at a distribution warehouse. To accomplish the purpose two research questions were formulated: Which critical constraints can occur in the material flow in the inbound process at a distribution warehouse? How can the identified constraints be excluded in the inbound process? Method – The study was performed inductively, and the data collection techniques were interviews, observations, document studies and literature studies. A single case study was performed at a distribution warehouse and the empirical data and theories were compared to accomplish the purpose of the study. Findings – The result of the study demonstrates that the critical constraints in the inbound process at a distribution warehouse are space, material handling, automatic systems and warehouse layout. The conclusion of the study is that the constraints are connected and affect each other since they are all included in the same process. To exclude the constraints different types of standards should be implemented in the inbound process, and distribution warehouses should work with continuous improvements. Implications – The study does not contribute to new theories but can be practically beneficial for distribution warehouses similar to the studies case study. Limitations – The study only focuses on one distribution warehouse and is therefore a single case study. The generalizability could have been higher if the study had been conducted at multiple distribution warehouses.

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González, González Diana Cristina 1984. "Uso de parâmetros multifractais no reconhecimento de locutor." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259422.

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Orientadores: Lee Luan Ling, Fábio Violaro Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação Made available in DSpace on 2018-08-19T05:40:32Z (GMT). No. of bitstreams: 1 GonzalezGonzalez_DianaCristina_M.pdf: 2589944 bytes, checksum: ddbbbef6076eb402f4abe638ebcd232b (MD5) Previous issue date: 2011 Resumo: Esta dissertação apresenta a implementação de um sistema de Reconhecimento Automático de Locutor (ASR). Este sistema emprega um novo parâmetro de características de locutor baseado no modelo multifractal "VVGM" (Variable Variance Gaussian Multiplier). A metodologia adotada para o desenvolvimento deste sistema foi formulada em duas etapas. Inicialmente foi implementado um sistema ASR tradicional, usando como vetor de características os MFCCs (Mel-Frequency Cepstral Coefficients) e modelo de mistura gaussiana (GMM) como classificador, uma vez que é uma configuração clássica, adotada como referência na literatura. Este procedimento permite ter um conhecimento amplo sobre a produção de sinais de voz, além de um sistema de referência para comparar o desempenho do novo parâmetro VVGM. A segunda etapa foi dedicada ao estudo de processos multifractais em sinais de fala, já que eles enfatizam-se na análise das informações contidas nas partes não estacionárias do sinal avaliado. Aproveitando essa característica, sinais de fala são modelados usando o modelo VVGM. Este modelo é baseado no processo de cascata multiplicativa binomial, e usa as variâncias dos multiplicadores de cada estágio como um novo vetor de característica. As informações obtidas pelos dois métodos são diferentes e complementares. Portanto, é interessante combinar os parâmetros clássicos com os parâmetros multifractais, a fim de melhorar o desempenho dos sistemas de reconhecimento de locutor. Os sistemas propostos foram avaliados por meio de três bases de dados de fala com diferentes configurações, tais como taxas de amostragem, número de falantes e frases e duração do treinamento e teste. Estas diferentes configurações permitem determinar as características do sinal de fala requeridas pelo sistema. Do resultado dos experimentos foi observado que o sistema de identificação de locutor usando os parâmetros VVGM alcançou taxas de acerto significativas, o que mostra que este modelo multifractal contém informações relevantes sobre a identidade de cada locutor. Por exemplo, a segunda base de dados é composta de sinais de fala de 71 locutores (50 homens e 21 mulheres) digitalizados a 22,05 kHz com 16 bits/amostra. O treinamento foi feito com 20 frases para cada locutor, com uma duração total de cerca de 70 s. Avaliando o sistema ASR baseado em VVGM, com locuções de teste de 3 s de comprimento, foi obtida uma taxa de reconhecimento de 91,30%. Usando estas mesmas condições, o sistema ASR baseado em MFCCs atingiu uma taxa de reconhecimento de 98,76%. No entanto, quando os dois parâmetros foram combinados, a taxa de reconhecimento aumentou para 99,43%, mostrando que a nova característica acrescenta informações importantes para o sistema de reconhecimento de locutor Abstract: This dissertation presents an Automatic Speaker Recognition (ASR) system, which employs a new parameter based on the ¿VVGM? (Variable Variance Gaussian Multiplier) multifractal model. The methodology adopted for the development of this system is formulated in two stages. Initially, a traditional ASR system was implemented, based on the use of Mel-Frequency Cepstral Coefficients (MFCCs) and the Gaussian mixture models (GMMs) as the classifier, since it is the method with the best results in the literature. This procedure allows having a broad knowledge about the production of speech signals and a reference system to compare the performance of the new VVGM parameter. The second stage was dedicated to the study of the multifractal processes for speech signals, given that with them, it is possible to analyze information contained in non-stationary parts of the evaluated signal. Taking advantage of this characteristic, speech signals are modeled using the VVGM model, which is based on the binomial multiplicative cascade process, and uses the variances of multipliers for each state as a new speech feature. The information obtained by the two methods is different and complementary. Therefore, it is interesting to combine the classic parameters with the multifractal parameters in order to improve the performance of speaker recognition systems. The proposed systems were evaluated using three databases with different settings, such as sampling rates, number of speakers and phrases, duration of training and testing. These different configurations allow the determination of characteristics of the speech signal required by the system. With the experiments, the speaker identification system based on the VVGM parameters achieved significant success rates, which shows that this multifractal model contains relevant information of the identity of each speaker. For example, the second database is composed of speech signals of 71 speakers (50 men and 21 women) digitized at 22.05 kHz with 16 bits/sample. The training was done with 20 phrases for each speaker, with an approximately total duration of 70 s. Evaluating the ASR system based on VVGM, with this database and using test locutions with 3s of duration, it was obtained a recognition rate of 91.3%. Using these same conditions, the ASR system based on MFCCs reached a recognition rate of 98.76%. However, when the two parameters are combined, the recognition rate increased to 99.43%, showing that the new feature adds substantial information to the speaker recognition system Mestrado Telecomunicações e Telemática Mestre em Engenharia Elétrica

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Cho, Namhun. "Allocation of individual harmonic emission limits in accordance with the principles of IEC/TR 61000-3-6." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49075.

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A model of the accurate harmonic allocation methods is developed to improve the current emission limits of IEEE Std.519. IEC 61000-3-6 and IEEE Std. 519 have by now been accepted as two well known standards for interconnecting the MV and HV-EHV customers to utility systems and widely adopted as standards to many power utilities. It is worth noting that the harmonic current emission limits of both standards have not been compared and justified with analytical proofs because there is still no explanation that discusses the origin of the emission limits in IEEE Std. 519, or the complex feature of IEC 61000-3-6. Two new novel methods of allocating the harmonic current emission limits for MV customers and HV-EHV customers have been proposed. Both methods have been developed in accordance with the principles of IEC 61000-3-6. Task II has compared and investgated the emission limits of both IEC 61000-3-6 and IEEE Std. 519. The difference, inconsistency and inaccuracy have been proven with the perspective of practical evaluations based on their own principles. The investigations focus on the specific numerical proofs of the resulting voltage distortions and the current emission limits in the MV and HV-EHV systems rather than on the philosophies. The proposed methods strongly support IEC 61000-3-6 and IEEE Std. 519, and add to their value; these methods could also help utilities allocate fairly and accurately harmonic emission limits to their MV and HV-EHV customers.

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Tibiriçá, Álvaro Messias Bigonha. "Um estudo sobre os sistemas de iluminação automáticos e os sistemas de controle distribuído para automação predial." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-04022016-094546/.

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Este trabalho faz um levantamento dos Sistemas de Iluminação Automáticos (SIA) utilizados atualmente, das tecnologias empregadas e das linhas de pesquisas que vêm surgindo neste tema. É analisada também a relação dos sistemas de controle distribuído (SCD) com os SIA e com a automação predial. Um estudo de caso de um SIA que utiliza um SCD como plataforma tecnológica também é analisado. Ao final da dissertação, propõe-se uma tese, fruto das análises feitas durante este trabalho, que visa aumentar a modularidade, a flexibilidade e a interoperabilidade dos sistemas de automação predial baseados em SCD. Durante a dissertação são descritas: as características da luz; a relação entre a luz e o ser humano; os principais componentes de um SIA; as características básicas de um SCD; e a tecnologia Lonworks. This work describes the Illumination Automatic Systems (IAS) used nowadays, the used technologies and the research lines that arise in this knowledge area. It\'s also analyzed the relation between Distributed Control Systems (DCS), IAS and building automation. A case study is done with a system that uses IAS and DCS. In the end of this work, it\'s suggested a thesis, result of analyses done during this work, with the objective of increasing the modularity, flexibility and interoperability of buildings automation systems based on DCS technologies. During this dissertation is described: the light characteristics; the relation between light and the human being; the main components of IAS; the characteristics of a DCS; and the Lonworks technology.

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Gomes, Ricardo Borges. "Resolução do problema de fluxo de carga para redes de distribuição utilizando o metodo desacoplado rapido com rotação automatica de eixos." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261715.

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Orientador: Carlos Alberto de Castro Junior Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação Made available in DSpace on 2018-08-06T19:37:05Z (GMT). No. of bitstreams: 1 Gomes_RicardoBorges_M.pdf: 725231 bytes, checksum: e24b9811f14e33910092b2f639a89050 (MD5) Previous issue date: 2006 Resumo: O método desacoplado rápido (MDR) [2] é uma variante do tradicional método de Newton [1] para a resolução do problema de fluxo de carga (obtenção do estado de operação de redes elétricas de potência). Sabe-se que o MDR apresenta desempenho insatisfatório quando aplicado a redes de distribuição, devido à desfavorável relação r/x dos ramos, resultando num processo de cálculo que pode apresentar divergência ou convergência lenta (grande número de iterações). Há algum tempo foi proposta uma alteração no MDR, chamada de rotação de eixos[4], que melhora as características de convergência do método. A idéia consiste em obter uma rede fictícia para a qual o MDR funcione bem e cujo estado de operação (magnitudes e ângulos de tensão) seja o mesmo da rede original. O valor do ângulo de rotação de eixos, único para toda a rede, é determinado empiricamente. Recentemente uma outra proposta de rotação ótima de eixos[5] foi apresentada, sugerindo modificações ao método que trouxeram maior automação aos cálculos, apesar de efeitos desfavoráveis em relação à manipulação de matrizes e ao significado físico da rede elétrica durante o processo iterativo. O presente trabalho traz um novo algoritmo de rotação de eixos que supera algumas desvantagens dos métodos apresentados em [4, 5], com bom desempenho. Além disso, traz uma interessante contribuição sobre a rotação de barras do tipo PV, não abordado anteriormente Abstract: The fast decoupled loadflow (FDLF) [2] is a variant of the traditional Newton method [1] for solving the loadflow problem (find the operational state of electrical power networks). It is well-known that FDLF presents unsatisfactory performance when applied to distribution systems. Their unfavourable r/x branch ratios may lead to divergence or slow convergence (large number of iterations). A modification to the FDLF, called axesrotation[4], was proposed some time ago, which improves convergency of the method. The idea is to obtain a fictitious network for which the FDLF performs better and which operational state (voltage magnitudes and angles) is the same as the original network. However, the rotation angle is determined empirically. Recently the optimal axes rotation[5] was presented, suggesting some modifications that led to more automated calculations, despite of some undesirable effects on matrices handling and also to the physical meaning of networks during the iterative process. This research work presents a new algorithm for axes rotation that overcomes some disadvantages found in [4, 5], with good performance. Moreover, it brings an interesting contribution on the rotation of PV buses, not previously considered. Mestrado Energia Eletrica Mestre em Engenharia Elétrica

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Erden, Mustafa Suphi. "Six-legged Walking Machine: The Robot-ea308." Phd thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607356/index.pdf.

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The work presented in this thesis aims to make contribution to the understanding and application of six-legged statically stable walking machines in both theoretical and practical levels. In this thesis five pieces of work, performed with and for the three-joint six-legged Robot-EA308, are presented: 1) Standard gaits, which include the well-known wave gaits, are defined and a stability analysis, in the sense of static stable walking, is performed on an analytical level. Various definitions are given theorems are stated and proved. 2) A free gait generation algorithm with reinforcement learning is developed. Its facilities of stability improvement, smooth speed changes, and adaptation in case of a rear-leg deficiency with learning of five-legged walking are experimented in real-time on the Robot-EA308. 3) Trajectory optimization and controller design is performed for the protraction movement of a three-joint leg. The trajectory generated by the controller is demonstrated with the Robot-EA308. 4) The full kinematic-dynamic formulation of a three-joint six-legged robot is performed with the joint-torques being the primary variables. It is demonstrated that the proposed torque distribution scheme, rather than the conventional force distribution, results in an efficient distribution of required forces and moments to the supporting legs. 5) An analysis of energy efficiency is performed for wave gaits. The established strategies for determination of gait parameters for an efficient walk are justified using the Robot-EA308.

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Andersson, Daniel, and Glen Edman. "Effektivisering av mjukvaruinstallationer : Genom automatiserad mjukvarudistribution." Thesis, Högskolan Dalarna, Informatik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:du-14641.

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Software deployment, eller mjukvarudistribution översatt till svenska kan ses som processen där alla aktiviteter ingår för att göra en mjukvara tillgänglig för användare utan en manuell installation på användarens dator eller annan maskin. Det finns ett flertal software deployment-verktyg, som hanterar automatiska installationer, tillgängliga för företag på marknaden idag. Avdelningen HVDC på ABB i Ludvika har behov att börja använda ett verktyg för automatiserade installationer av mjukvaror då installationer idag utförs manuellt och är tidsödande. Som Microsoftpartners vill ABB se hur Microsofts verktyg för mjukvarudistribution skulle kunna hjälpa för detta behov. Vår studie syftade till att undersöka hur arbetet med installationer av mjukvara ser ut idag, samt hitta förbättringsmöjligheter för installationer som inte kan automatiseras i nuläget. I studien ingick även att ta fram ett generellt ramverk för hur verksamheter kan gå tillväga när de vill börja använda sig utav software deployment-verktyg. I ramverket ingår en utformad kravspecifikation som ska utvärderas mot Microsofts verktyg. För att skapa en uppfattning om hur arbetet i verksamheten ser ut idag har vi utfört enkätundersökning och intervjuer med personal på HVDC. För att utveckla ett ramverk har vi använt oss av insamlade data från de intervjuer, enkätundersökning och gruppintervju som utförts, detta för att identifiera krav och önskemål från personalen hos ett software deployment-verktyg. Litteraturstudier utfördes för att skapa en teoretisk referensram att utgå ifrån vid utvecklande av ramverket och kravspecifikationen. Studien har resulterat i en beskrivning av software deployment, förbättringsmöjligheter i arbetet med installationer av mjukvara samt ett generellt ramverk som beskriver hur verksamheter kan gå tillväga när de ska börja använda ett software deployment-verktyg. Ramverket innehåller också en kravspecifikation som använts för att utvärdera Microsofts verktyg för mjukvarudistribution. I vår studie har vi inte sett att någon tidigare har tagit fram ett generellt ramverk och kravspecifikation som verksamheter kan använda sig av som underlag när de ska börja använda ett software deployment-verktyg. Vårt resultat av studien kan täcka upp detta kunskapsgap. Software deployment can be seen as the process where all activities are included to make a software available to users without a manual installation on the user’s computer or other machine. There are several software deployment tools that manage automated installations available to enterprises on the market today. The department HVDC at ABB in Ludvika has needs of starting to use a tool for automated installations of software which currently is installed manually and is time consuming. As Microsoft partners ABB wants to see how Microsoft’s tool for software deployment could help for this need. Our study aimed to investigate how the department´s work with installations of software looks like today and to find opportunities for improvement for installations that can’t be automated at this time. The study also includes to develop a general framework for how businesses can proceed when they want to start using a software deployment tool. The framework also includes a designed requirement specification that will be evaluated against Microsoft´s tool. To create an idea of how the work in the business looks like today, we have performed surveys and interviews with staff in HVDC. In order to develop a framework, we have used the data collected from the interviews, questionnaires and group interviews conducted to identify requirements and wishes from the staff of a software deployment tool. Literature studies were also conducted to create a theoretical framework to use when developing the framework and the requirement specification. Our studies have resulted in a description of software deployment, opportunities for improvement in the work of software installations and a general framework that describes how businesses can proceed when they are about to start using a software deployment tool. The framework also provides a set of requirements that have used to evaluate Microsoft's tool for software distribution. In our study we have not seen that anyone before have developed a general framework and requirements specification that businesses can use as a basis when to start using a software deployment tool. Our results of the study can cover up this knowledge gap.

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Mandel, Denis. "Diagnostic à base de redondance analytique : application à un réseau urbain de distribution d'eau potable." Vandoeuvre-les-Nancy, INPL, 1998. http://www.theses.fr/1998INPL127N.

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Le développement des systèmes de supervision permet d'obtenir une image de plus en plus précise de l'état de fonctionnement d'un processus en fournissant une quantité importante d'informations. En contrepartie, cette masse d'informations rend la surveillance plus complexe. Il s'avère alors indispensable de rendre les procédures de surveillance automatiques. Ces procédures doivent être capables d'appréhender les dysfonctionnements du processus mais également les défaillances du système d'instrumentation de manière à éliminer les mesures erronées, avant que leurs effets ne soient néfastes. Dans le premier chapitre de ce mémoire les concepts fondamentaux et les principales approches du diagnostic sont présentés afin de définir le cadre général de nos travaux. Dans le second chapitre, le problème de la localisation de défauts à base de redondance analytique est abordé. À partir de l'analyse des avantages et inconvénients de méthodes classiques, des améliorations et des nouvelles méthodes, utilisant par exemple des concepts flous ou encore l'arithmétique des intervalles, sont proposées. Le troisième chapitre est consacré au placement de capteurs en vue de la surveillance. Tout d'abord différents critères de performance d'un système d'instrumentation sont définis. Certains de ces critères sont utilisés par la suite pour l'élaboration d'une méthode originale de placement de capteurs. Cette méthode à pour objet de définir l'instrumentation la moins couteuse répondant à un cahier des charges décrivant les performances à atteindre pour la surveillance. Une application réalisée dans le cadre d'une collaboration avec la communauté urbaine du grand Nancy fait l'objet du quatrième chapitre. Cette application concerne la surveillance du réseau de distribution d'eau potable de l'agglomération nancéienne. Nous avons élaboré pour ce réseau d'eau une procédure de surveillance à base de redondance analytique, que nous avons exploité pour développer un logiciel d'aide à la surveillance.

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Mattos, Marcel Souza. "Uma contribuição para a parametrização da proteção em sistemas de distribuição considerando custo de interrupções." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/148681.

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A continuidade no fornecimento de energia elétrica a clientes é um objetivo constante das distribuidoras de energia, as quais estão constantemente buscando desenvolver soluções tecnológicas a fim de melhorar o desempenho das redes de distribuição. Com o crescimento das cargas eletrônicas e o expressivo aumento dos dispositivos automáticos nas redes, surge uma nova forma de analisar a rede de distribuição sob o aspecto da filosofia da proteção, considerando interrupções sustentadas e momentâneas, sob dois aspectos distintos, o primeiro considera o custo da energia não fornecida sob o período de contingência, enquanto que o segundo refere-se ao impacto do custo social para diferentes classes de clientes, durante o período das interrupções. Desta forma este trabalho propõe o desenvolvimento de uma estratégia de minimização de custos dessas interrupções considerando as características das cargas, bem como o tempo necessário para reinicialização da carga. Para este fim, é aplicado um modelo de programação não-linear, que emprega variáveis binárias para definir a habilitação ou não de curvas rápidas nos religadores e uma abordagem de otimização clássica. Os algoritmos foram desenvolvidos no software Matlab e posteriormente convertido para linguagem GAMS (Generic Algebraic Modeling System). A metodologia foi testada e validada em um alimentador de distribuição real urbano, localizado na região metropolitana de Porto Alegre (RS, Brasil). Uninterrupted power delivery is a permanent goal of power utilities. One way of attaining this objective is constantly investing in technological solutions to improve the performance of distribution networks. With increasing loads, mainly electronic ones, as well as growing insertion of automatic reclosers, the protection philosophy of distribution systems has to be rethought taking into account temporary and permanent interruptions. In this work, we propose a strategy to minimize the cost of interruptions taking into account the load characteristics and the time required to restart the load. This is achieved by deriving a mixed integer nonlinear programming model. The proposed model uses binary variables to define if the instantaneous characteristic of the recloser should be enabled and a classical explicit mathematical optimization approach. The algorithms were developed with Matlab software and the conversion was made to a General Algebraic Modeling System (GAMS). The applicability of the proposed methodology is tested in an actual feeder from Porto Alegre.

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Sastry, Jyoti. "Direct AC control of grid assets." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41109.

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The objective of the proposed research is to investigate feasible approaches to dynamic control of the power grid. Growth in the demand for electric power, and an increase in the penetration of renewable energy resources are causing congestion on an already aging power grid. Conventional grid control involves the use of static assets that operate on long time scales. These assets provide no dynamic control on the grid, and are typically used for scheduled support. Existing solutions (FACTS devices) to dynamic grid control have seen minimal market penetration because of high cost and low reliability. The proposed research provides a solution for dynamic control of the power grid that augments existing grid assets with a thin AC converter (TACC) to realize enhanced dynamic control. The TACC is a direct AC converter with filter elements and no bulk energy storage that dynamically reflects the asset value on the grid. The converter has a fail-normal mode of operation that returns the asset to its initial operating state, thereby not degrading system reliability. Some applications of TACCs include Inverter-Less STATCOMs and Controllable Network Transformers, which are realized by augmenting shunt VAR capacitors and load tap changers respectively. The principle of virtual quadrature sources is proposed to enable conditioning of AC voltages and currents. The concept is a novel method to realize control of phase angle and, or harmonics in single-phase AC converters, with no bulk energy storage. This concept is used to control the TACC and provides the asset with significantly enhanced control capabilities. Scaling of the TACC to utility voltage and power levels has been addressed by proposing a novel multilevel direct AC converter. The concept proposes the use of commercially available low cost semiconductor devices to realize high power converters. The specific application chosen to validate the concept of TACCs, through a medium voltage design, is the Inverter-less STATCOM.

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Kalalas, Charalampos. "Cellular networks for smart grid communication." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/620760.

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The next-generation electric power system, known as smart grid, relies on a robust and reliable underlying communication infrastructure to improve the efficiency of electricity distribution. Cellular networks, e.g., LTE/LTE-A systems, appear as a promising technology to facilitate the smart grid evolution. Their inherent performance characteristics and well-established ecosystem could potentially unlock unprecedented use cases, enabling real-time and autonomous distribution grid operations. However, cellular technology was not originally intended for smart grid communication, associated with highly-reliable message exchange and massive device connectivity requirements. The fundamental differences between smart grid and human-type communication challenge the classical design of cellular networks and introduce important research questions that have not been sufficiently addressed so far. Motivated by these challenges, this doctoral thesis investigates novel radio access network (RAN) design principles and performance analysis for the seamless integration of smart grid traffic in future cellular networks. Specifically, we focus on addressing the fundamental RAN problems of network scalability in massive smart grid deployments and radio resource management for smart grid and human-type traffic. The main objective of the thesis lies on the design, analysis and performance evaluation of RAN mechanisms that would render cellular networks the key enabler for emerging smart grid applications. The first part of the thesis addresses the radio access limitations in LTE-based networks for reliable and scalable smart grid communication. We first identify the congestion problem in LTE random access that arises in large-scale smart grid deployments. To overcome this, a novel random access mechanism is proposed that can efficiently support real-time distribution automation services with negligible impact on the background traffic. Motivated by the stringent reliability requirements of various smart grid operations, we then develop an analytical model of the LTE random access procedure that allows us to assess the performance of event-based monitoring traffic under various load conditions and network configurations. We further extend our analysis to include the relation between the cell size and the availability of orthogonal random access resources and we identify an additional challenge for reliable smart grid connectivity. To this end, we devise an interference- and load-aware cell planning mechanism that enhances reliability in substation automation services. Finally, we couple the problem of state estimation in wide-area monitoring systems with the reliability challenges in information acquisition. Using our developed analytical framework, we quantify the impact of imperfect communication reliability in the state estimation accuracy and we provide useful insights for the design of reliability-aware state estimators. The second part of the thesis builds on the previous one and focuses on the RAN problem of resource scheduling and sharing for smart grid and human-type traffic. We introduce a novel scheduler that achieves low latency for distribution automation traffic while resource allocation is performed in a way that keeps the degradation of cellular users at a minimum level. In addition, we investigate the benefits of Device-to-Device (D2D) transmission mode for event-based message exchange in substation automation scenarios. We design a joint mode selection and resource allocation mechanism which results in higher data rates with respect to the conventional transmission mode via the base station. An orthogonal resource partition scheme between cellular and D2D links is further proposed to prevent the underutilization of the scarce cellular spectrum. The research findings of this thesis aim to deliver novel solutions to important RAN performance issues that arise when cellular networks support smart grid communication. Las redes celulares, p.e., los sistemas LTE/LTE-A, aparecen como una tecnología prometedora para facilitar la evolución de la próxima generación del sistema eléctrico de potencia, conocido como smart grid (SG). Sin embargo, la tecnología celular no fue pensada originalmente para las comunicaciones en la SG, asociadas con el intercambio fiable de mensajes y con requisitos de conectividad de un número masivo de dispositivos. Las diferencias fundamentales entre las comunicaciones en la SG y la comunicación de tipo humano desafían el diseño clásico de las redes celulares e introducen importantes cuestiones de investigación que hasta ahora no se han abordado suficientemente. Motivada por estos retos, esta tesis doctoral investiga los principios de diseño y analiza el rendimiento de una nueva red de acceso radio (RAN) que permita una integración perfecta del tráfico de la SG en las redes celulares futuras. Nos centramos en los problemas fundamentales de escalabilidad de la RAN en despliegues de SG masivos, y en la gestión de los recursos radio para la integración del tráfico de la SG con el tráfico de tipo humano. El objetivo principal de la tesis consiste en el diseño, el análisis y la evaluación del rendimiento de los mecanismos de las RAN que convertirán a las redes celulares en el elemento clave para las aplicaciones emergentes de las SGs. La primera parte de la tesis aborda las limitaciones del acceso radio en redes LTE para la comunicación fiable y escalable en SGs. En primer lugar, identificamos el problema de congestión en el acceso aleatorio de LTE que aparece en los despliegues de SGs a gran escala. Para superar este problema, se propone un nuevo mecanismo de acceso aleatorio que permite soportar de forma eficiente los servicios de automatización de la distribución eléctrica en tiempo real, con un impacto insignificante en el tráfico de fondo. Motivados por los estrictos requisitos de fiabilidad de las diversas operaciones en la SG, desarrollamos un modelo analítico del procedimiento de acceso aleatorio de LTE que nos permite evaluar el rendimiento del tráfico de monitorización de la red eléctrica basado en eventos bajo diversas condiciones de carga y configuraciones de red. Además, ampliamos nuestro análisis para incluir la relación entre el tamaño de celda y la disponibilidad de recursos de acceso aleatorio ortogonales, e identificamos un reto adicional para la conectividad fiable en la SG. Con este fin, diseñamos un mecanismo de planificación celular que tiene en cuenta las interferencias y la carga de la red, y que mejora la fiabilidad en los servicios de automatización de las subestaciones eléctricas. Finalmente, combinamos el problema de la estimación de estado en sistemas de monitorización de redes eléctricas de área amplia con los retos de fiabilidad en la adquisición de la información. Utilizando el modelo analítico desarrollado, cuantificamos el impacto de la baja fiabilidad en las comunicaciones sobre la precisión de la estimación de estado. La segunda parte de la tesis se centra en el problema de scheduling y compartición de recursos en la RAN para el tráfico de SG y el tráfico de tipo humano. Presentamos un nuevo scheduler que proporciona baja latencia para el tráfico de automatización de la distribución eléctrica, mientras que la asignación de recursos se realiza de un modo que mantiene la degradación de los usuarios celulares en un nivel mínimo. Además, investigamos los beneficios del modo de transmisión Device-to-Device (D2D) en el intercambio de mensajes basados en eventos en escenarios de automatización de subestaciones eléctricas. Diseñamos un mecanismo conjunto de asignación de recursos y selección de modo que da como resultado tasas de datos más elevadas con respecto al modo de transmisión convencional a través de la estación base. Finalmente, se propone un esquema de partición de recursos ortogonales entre enlaces celulares y D2

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Vianna, João Tito Almeida. "Métodos determinísticos para detecção e localização por área de faltas monofásicas de alta impedância sustentadas nos circuitos primários de sistemas de distribuição desequilibrados." Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/4039.

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Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-04-11T15:15:34Z No. of bitstreams: 1 joaotitoalmeidavianna.pdf: 4307092 bytes, checksum: 061d2a47a7e37bf6c1a1875c27f352ad (MD5) Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-04-18T12:47:46Z (GMT) No. of bitstreams: 1 joaotitoalmeidavianna.pdf: 4307092 bytes, checksum: 061d2a47a7e37bf6c1a1875c27f352ad (MD5) Made available in DSpace on 2017-04-18T12:47:46Z (GMT). No. of bitstreams: 1 joaotitoalmeidavianna.pdf: 4307092 bytes, checksum: 061d2a47a7e37bf6c1a1875c27f352ad (MD5) Previous issue date: 2016-09-05 O presente trabalho tem por objetivo o desenvolvimento de alternativas para detecção de faltas de alta impedância (HIFs) sustentadas em sistemas de distribuição. Como a maioria destas faltas é monofásica, enfoque foi dado para este tipo de falta no desenvolvimento do trabalho. Devido ao desequilíbrio e a variação da carga dos sistemas de distribuição, a proteção tradicional dos mesmos apresenta dificuldades na detecção destas faltas, que acabam se sustentando no sistema. Isso acarreta um risco de segurança pública, na medida em que estruturas externas ao sistema elétrico são mantidas energizadas representando risco a vidas que entrem em contato com elas. Características da topologia típica de sistemas de distribuição brasileiros (conhecida como do “tipo europeu”) foram exploradas de forma a se elaborar duas propostas de métodos de detecção e localização de HIFs. Ambos os métodos se baseiam na alocação de medidores alocados ao longo do sistema de distribuição, cujas medidas são integradas a uma central de dados via rede de comunicação. Nesta central, as medidas recebidas são analisadas de forma a diagnosticar a presença e localização de faltas monofásicas de alta impedância no sistema e emitir alarmes que descrevam a situação atual do mesmo. O primeiro método, o PDSZ, baseia-se em medições fasoriais sincronizadas e, além da detecção e localização, conta com um algoritmo de classificação das fases envolvidas na falta. Já o segundo (PQDSZ) baseia-se em medições não fasoriais e não possui esta última funcionalidade. Ambos os métodos são implementados em laboratório e simulados com o uso de um Simulador Digital de Tempo Real (RTDS), o que permite uma validação bem próxima da aplicação dos métodos em um sistema real. Tais simulações comprovam a aplicabilidade dos métodos propostos e todos os resultados são analisados de forma a confirmar este fato. This work aims to develop alternatives for the detection of sustained high impedance faults (HIFs) on distribution power systems. As the majority of these faults are single phase ones, the development was focused on this kind of fault. Due to load unbalance and variation of the distribution systems, the traditional protectiontechniques presents problems on detecting these faults, which are kept sustained on the system. This situation represents a serious public hazard, because the external electrical system structure remains energized, representing a risk to lives that eventually get in touch with it. There is also the risk of starting a fire from this fault point. Topologycal features of Brasilian distribution systems (known as “european type”) were exploited in order to elaborate two methods for detection and localization of HIFs. Both methods are based on the use of meters alocated along the distribution system, whose measurements are sent to a central data concentrator, through a network communication. Then, the received measurements are analysed in order to diagnose the ocurrence of single phase high impedance faults on the system and send alarms that describe the current system situation. The first method, named PDSZ, is based on Phasor Measurement Units (PMUs) and besides detecting and locating the fault, can also classify it, showing which phaseis involved. The second one, the PQDSZ, is based on non-synchronized measurements and can not classify the fault. Both methods were implemented on laboratory and tested using real equipament and a Real Time Digital Simulator (RTDS), which allows a very precise evaluation of the proposed methods, emulating conditions very similar the real ones. The simulations prove the aplicability of the proposed methods and the results are analysed in order to show the effectiveness of the proposed methods.

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Pradella, Lorenzo. "A data-driven prognostic approach based on AR identification and hidden Markov models." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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In this work a data-driven prognostic approach based on AutoRegressive (AR) estimation and hidden Markov models (HMMs) is addressed. In particular, the approach is capable of achieving Prognostic and Health Management (PHM) tasks such as real time detection and Remaining Useful Life (RUL) estimation. The approach can be seen as composed of a training part (offline) and an exploitation part (online). The offline part relies upon the use of a scalar health indicator coming from the system identification field: the Itakura Saito (IS) spectral distance. In particular, raw acceleration data, gathered in an unsupervised framework from the machine, are modeled by AR processes and then transformed into IS. Then, HMMs are used to map such IS signals into a finite number of parameters. Moreover, in the training procedure of HMMs, a left-to-right clustering of unsupervised data, based on Mixture of Gaussians (MOG) distribution is proposed. During the online exploitation a simulation of a running signal is tested against trained ones in order to carry out PHM tasks in real time. Simulations have been performed using a public benchmark available in ”NASA prognostic data repository”. It contains run-to-failure tests on bearings, on which acceleration signals are gathered. In particular the gathering experiment simulates an industry application, under constant operating conditions. Results of simulations, performed on real time data, validate the proposed prognostic approach and make the combined use of IS an HMMs a reliable way in achieving PHM goals.

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Tung, Chuan-Chi, and 董群驥. "The Reliability Study of Distribution Feeder Automation System." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/64926392999411301413.

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碩士 輔仁大學 資訊管理學系碩士在職專班 103 In the traditional way, Taiwan Power Company’s (TPC) distribution feeder for electrical power supply accidentally caused damage (break down) by natural disaster (ex: typhoon, earthquake…) or manual maintaining malfunction (fracture of service wire or cable). A Distribution Feeder Automation System (DFAS) is essential for modern sophisticated power supply network. DFAS can detect the power failure areas (fault detection), isolate the break-down areas (fault isolation) and resume power supply in no time. DFAS not only narrow power outage region but also shorten power service restoration. To offer a zero fault, high quality power supply to all the families in Taiwan has always been an aggressive policy of TPC. A faultless power supply network relies on the reliability of Distribution Feeder Automation System. The well-functioning DFAS ensures the reputation of TPC. This research targets on TPC’s Distribution Feeder Automation System by monitoring its instance database and interviewing the specialist, who operated DFAS. By promoting the reliability of DFAS, this research also analyzes the key factors that malfunctioning the DFAS, takes precautions against a calamity.

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Chen, Chyi Wen, and 陳麒文. "A Study on Communication Protocol for Distribution System Automation." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/31852317750105867080.

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碩士 國立中山大學 電機工程研究所 83 Due to rapid economy growth, the electricity users require a higher quality of the service. A short period outage could cause a great deal of customer complaint and loss of revenue. In order to continue improving the electric power supply, many distribution automation functions have been suggested to solve the problems. The distribution automation system uses SCADA system to collect data from the field and perform supervisory controls of pertinent equipments. In order to achieve these functions, a communication protocol need to be specified to be followed by various parties involved in the system. In this thesis, based on the communication protocol current used by Taiwan Power Company, a modified distribution automation communication protocol is designed to extend the distribution automation functions for covering feeder automation and load management. A distribution line carrier module based on 8051 chip is setup to test some of the function codes transmitted on a simplified distribution lines.

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Wang, Chu-Liao, and 王主料. "A Floorplan-Based Power Distribution Network Design Automation System." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/30633436746759574484.

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碩士 中原大學 電子工程研究所 90 As the process technology enters the deep sub-micron design era, electromigration and voltage drop issues become more crucial for reliable and high performance ASIC designs. However, it is very expensive to fix the power distribution network after the detailed layout composition is completed. In order to avoid the iterations including placement and routing, the power distribution network should be accurately planned at the post-floorplan stage. In this thesis, we will study design methodology of floorplan-based power distribution network. Compared with other approaches, the main distinction of our approach is that it presents a systematic method to build an initial feasible power distribution network such that excellent voltage regulation in the power demand across the chip is achieved. Then, by iteratively improving the power distribution network based on simulated evolution, our optimization goal is to minimize the wiring resources under current density and voltage drop constraints. Experimental data shows that the proposed approach can construct robust power distribution networks with fewer routing areas. The proposed algorithm has been implemented in a C program and integrated with commercially available tools in existing ASIC design flow.

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XIAO, YING-DONG, and 蕭瑛東. "A study of expert system applied to power distribution automation." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/84840381028685569945.

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HUANG, Hsin-Yi, and 黃信益. "Compact Distribution Feeder Automation System Applied To Improve Power Quality." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/x3eg25.

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碩士 國立臺灣科技大學 電機工程系 94 This paper uses the compact distribution feeder automation system applied to improve power quality while outage occurred. Using the automation system, it can analyze the accidents with passed back SCADA point signals amount to 180 cycles from beginning to end, from its electric current value of every cycle. It can confirm and isolate the trouble block faster than the traditional method. This paper uses a real case study to demonstrate how to improve the power efficiency while the voltage vibrates too much. This practical case analysis proves this automation system will improve power quality and electric efficiency indeed.

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陳宏毅. "Study on distribution closed loop automation system in Taipei city." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/92114183625835706085.

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碩士 國立臺北科技大學 電機工程系碩士班 90 With rapid growth of population, serried high tower building, concentrations of utility, high consumer load and promotion of living standards in metropolis, and metropolis includes government major organization, commercial & financial organization, tourist hotel, major meeting, communication center and national defense commanding center etc.. How to decide the power supply system and system operation is very important theme between Taipower and Customer. In Taipei city, the distribution system was underground, but the type of distribution network was open loop. Taipower Taipei district office issued “No. 1 Distribution Closed Loop Automation System Project” Contract in April 2001, the project will change underground distribution networks from open loop to closed loop, and improve automation of all related equipment. The aim of this thesis is to evaluate “No. 1 Distribution Closed Loop Automation System Project”. First, describing the type of distribution network and design criteria of Taipower system, and important contents and special requirements of this project. Next, evaluating the configuration of distribution closed loop automation system for this project, fault current calculation analysis of distribution closed loop, and protective coordination of distribution closed loop including main feeder protection, loop switch busbar protection, branch loop protection and breaker failure backup protection. Finally, based on the previous research results, a conclusion was drawn. The research results are of value to the planning of next distribution close loop automation system project for Taipower.

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謝宗龍. "The Strategy Study of Reactive Power Compensation in Distribution System Automation." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/61009535326236721568.

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碩士 國立臺灣科技大學 電機工程系 89 The stability of power supply and electric energy had become into an important and concern topics gradually due to gross growth in industries and the increasing of living standard by people in Taiwan. The demand in electric energy increased annually. The research is devoted to study the effect and characteristic on the feeder in distribution lines due to the reactive power planning strategy was changed. The research investigates the electric performances in distribution lines before/after the circuit breaker trip by ETAP (Electric Transient Analyzer Program) to simulate and study the reactive power effectiveness. Based on the safety and operation constraints such as voltage variation, capacitor bank capacities, locations of the capacitor banks, the research attends to find the minimal loss objective performance by using artificial neural network technique. Finally, the best location and optimal planning of the capacitor banks in distribution lines has discussed in order to evaluate the probability and effectiveness. And a normally open- loop radial type distribution line has evaluated as an example to show the contribution of the research. The resultants proposed are helpful and valuable to distribution power system operation.

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張英正. "A Study on Configuration Planning and Application of Distribution Feeder Automation System." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/62184201006372011221.

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碩士 長庚大學 電機工程研究所 92 There are many configurations used in today’s distribution feeder automation systems. Among them, the normal-open loop automation system is the most frequently used configuration. In order to enhance the quality of customer’s service and the reliability of power supply, the normal-close loop and branch automation system will be gradually used. This thesis discusses the configuration building of whole planning procedures of distribution feeder automation system, and analyzes various operating strategies in normal-open loop and normal-close loop automation system. First of all, the configurations of distribution feeder automation system in some countries are introduced and reliability indexes are evaluated. After that, the functions of distribution automation subsystems and the integrations of the subsystems are described. Various planning types and control architectures of distribution feeder automation systems are also mentioned. Accordingly, the general needs of hardware and software are proposed. Finally, to verify the functions and benefits of feeder automation, some application examples in Taipower are examined. Furthermore, various operating strategies are analyzed in normal-open and normal-close loop system considering the situation when fault detection , isolation and service restoration (FDIR), work arrangement, overload and predicting of section load are needed. The study results show that for a good implementation of distribution feeder automation system, an appropriate pre-planning will be the key factor for future systems’ development, operation, maintenance, and reliability enhancement. This will also help the future expansion of an automation system.

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WANG, CHUNG-SHUN, and 汪忠順. "The Research of Distribution Automation System Trend of in the Domestic Development." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/72258821809028023166.

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碩士 大葉大學 電機工程學系碩士班 92 Before domestic not yet is developed in the early countryside society industry and commerce, the social populace to the electric power supplier request not high; But along with society and economy The development, also relatively enhances regarding the high quality and the high reliability electric power supply dependence, especially the society develops all the more consummates the ability which disturbs regarding the withstanding power cut accident to be also frailer. A complete electrical power system contains has three major parts: Namely for generating system, transmission system, and electrical power distribution system; However has directly with the social populace is connected, also is changes the most sensitive part to the social life is the electrical power distribution system, therefore the affiliation electrical power distribution system automation is improving the power supply reliability, has become one of modern electrical power distribution system development research main directions. This report main key point is compares to the present electrical power distribution system and difference of the implementation power distribution automated system, also discussion implementation power distribution automation to merit of the system; And the introduction analysis automation overhead construction and the principle, make the introduction analysis again to the domestic and foreign development survey; Discussion implementation power distribution automation to power supply reliability, benefit, and influence project necessity, then research discussion power distribution automation trend of in the domestic development, in addition will put forward the proposal to the future electrical power distribution system power supply way. Will penetrate this memoir, the reader has to the future electrical power distribution system development direction reveals and the explicit understanding.

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Chiang, Wen-Ping, and 江文平. "Benefit Analysis of Distribution Automation Switches Applied to the System Failure Handling." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/87084111500047959891.

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碩士 國立彰化師範大學 電機工程學系 101 Recently, with highly Taiwan's industrial development, the requirement for power quality and reliability is getting more stringent. Taiwan Power Company has thus been employing distribution automation switch system to actively enhance the restoration efficiency to improve power supply reliability and power quality increasing customer satisfaction and reducing losses. This paper introduces the distribution automation switching system architecture and their existing types, and briefly explains communication systems. With employing the least squares method to predict the optimal load distribution; the fault detection function can effectively reduce the power failure area, shorten power restoration time. In addition, by analyzing the quantitative data related to operations of the restoration capacity and quality of power supply, the benefits of installing distribution automation switching system is ascertained. The number of feeder trips can only be achieved with partial effectiveness for the factors of nature disturbance (thunder harm, typhoons, etc.); thus, its improvement can be further studied.

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Wang, Ji-Jhong, and 王基仲. "A Multiagent-Based Distribution Automation System for Service Restoration of Fault Contingencies." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/66858942334802636250.

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碩士 國立高雄應用科技大學 電機工程系 97 Distribution automation and customer automation have already been important development trend of power that obviously will enhance power service quality. A multiagent system is developed to enhance restoration quickly for fault contingencies on distribution systems with JADE in this thesis. The multiagent system (MAS) integrates the information of topology processor and loadings characteristics of service zones, distribution feeders and main transformers in substations to derive the proper restoration plan after the faulted location has been identified and isolated. The heuristic rules based on standard operation procedures of Taipower’s distribution system an included in the heat first search of the MAS to ensure the restoration plan derived will comply with the operation regulation. When the capacity reserves of supporting feeders and main transformers are not enough to cover the fault restoration for fault contingency, the load shedding is determined by the MAS to restore service to as many key customers as possible by considering the service priority of each service zone of distribution feeders. Besides, the thesis also considers the impact on the operation, planning and maintenance of distribution systems with distributed generation. The intention islanding for the feeder was analyzed after the execution of switching operation and load shedding procedure. Finally, it needs to analyze its stability by using Matlab/Simulink. A Taipower distribution system with 35 feeders is selected for computer simulation to demonstrate the effectiveness of the proposed methodology to solve the service restoration plan for distribution fault contingency by applying MAS.

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Hung, Wei-Chun, and 洪偉淳. "Enhancement of PV Penetration with Centralized Control Method in Distribution Automation System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/06158432816277121185.

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碩士 國立高雄應用科技大學 電機工程系博碩士班 101 The penetration level of a PV system is often limited due to the violation of voltage variation introduced by large intermittent power generation. This paper discusses the use of centralized control method in an Advanced Distribution Automation System (ADAS) to prevent voltage violation after load transfer between distribution feeders with high PV penetration level. The proposed method comprises three control phases with different control algorithms for regulating both reactive and active power output of PV inverters in a distribution system with multiple PV installations. Before the execution of load transfer, the voltage sensitivity analysis is performed to solve the total reactive power compensation required at the critical Point of Common Coupling (PCC) to prevent system voltage violation. With the proposed control algorithms, the ADAS system dispatches total reactive power compensation among PV systems according to the sensitivity coefficients and PV installation capacity and issues the control command to each PV inverter for adjustment of PV power generation so that the ancillary service of voltage support can be provided by all PV systems in a fairer manner. A practical Taipower distribution feeder pair is selected for computer simulation to verify the effectiveness of the proposed control method after load transfer between two feeders. With the proposed control method embedded in the ADAS system, the penetration level of PV installation in the distribution system can be increased by the ancillary service of all PV systems with fair reactive power compensation and active power curtailment, thus solving the voltage violation problem after load transfer between distribution feeders.

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Lee, Cheng-Tai, and 李承泰. "Study and Implementation of a DC Power Supply System for Distribution Automation Appliance." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/63499688535055113178.

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碩士 國立臺灣科技大學 電子工程系 93 Abstract The main objective of this thesis is to implement a DC power supply system for Distribution automation appliance, which satisfies the standard of electromagnetic interference (EMI) and low-order current harmonics. The power supply system consists of an EMI filter, a power factor corrector (PFC), a DC/DC converter, and a four-stage lead-acid battery charger with temperature compensation. The functions of power factor correction and DC/DC conversion in this system are fulfilled with a single control chip, FAN4803. Furthermore, in order to provide the best charging characteristics and to increase the lifetime of the battery, the charger will operates four charging modes according to the voltage status. Finally, the recorded data and waveforms from the experiments show the correctness of the design.

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Dissertations / Theses on the topic 'Distribution automation system'

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