Dissertations / Theses: 'Local power system'

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van, Eyk Helen, and helen vaneyk@health sa gov au. "Power, Trust and Collaboration: A case study of unsuccessful organisational change in the South Australian health system." Flinders University. Medicine, 2005. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20060130.095828.

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Internationally, health systems have been undergoing an extended period of endemic change, where one effort at health system reform inevitably seems to lead to further attempts to make adjustments, re-direct the focus of the reform effort, or bring about further, sometimes very different changes. This phenomenon is described as churning in this thesis. Churning is a result of continual efforts to adjust and ï¿½improveï¿½ health systems to address intractable ï¿½wickedï¿½ problems, often through applying solutions based on neo-liberal reform agendas that have influenced public sector reform in developed countries since the early 1980s. Consistent with this, the South Australian health system has been caught up in a cycle of change and restructuring for almost thirty years. This qualitative study explores a case study of unsuccessful organisational change initiated by a group of health care agencies in the southern metropolitan area of Adelaide, South Australia, which took place between 1996 and 2001. The agencies sought to develop and establish a regional health service through a process they called ï¿½Designing Better Health Care in the Southï¿½ which aimed to improve the way that services were provided in the area, and to enable the agencies to manage the increasing budgetary and workload pressures that they were all experiencing. A significant policy shift at the state government level meant that this initiative was no longer supported by the central bureaucracy and could not proceed. The agencies reverted from a focus on regional planning and service delivery to an institutional focus. The changes that are described within the scope of the case study are universally recognisable, including centralisation, decentralisation, managerialism and integration. The experience of Designing Better Health Care in the South as an unsuccessful attempt to implement change that was overtaken by other changes is also a universal phenomenon within health systems. This study locates the case study within its historical and policy contexts. It then analyses the key themes that emerge from consideration of the case study in order to understand the reasons for constant change, and the structural and systemic impediments to successful reform within the South Australian health system as an example of health systems in developed countries. As a case study of organisational change, Designing Better Health Care in the South was a story of frustration and disappointment, rather than of successful change. The case study of Designing Better Health Care in the South demonstrates the tensions between the differing priorities of central bureaucracy and health care agencies, and the pendulum swing between the aims of centralisation and regionalisation. The study uses the theory of negotiated order to understand the roles of the key themes of trust, partnership and collaboration, and power and control within the health system, and to consider how these themes affect the potential for the successful implementation of health care reform. Through analysis of the case study, this thesis contributes to an understanding of the difficulties of achieving effective reform within health systems in advanced economies, such as the South Australian health system, because of the complex power and trust relations that contribute to the functioning of the health system as a negotiated order. The study is multidisciplinary and qualitative, incorporating a number of social science disciplines including sociology, political science, historical analysis and organisational theory. Data collection methods for the study included interviews, focus groups, document analysis and a survey.

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Elkeelany, Omar S. A. Chaudhry Ghulam M. "A low-power embedded system design and synthesis of remotely programmable direct connect device core." Diss., UMK access, 2004.

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Thesis (Ph. D.)--School of Computing and Engineering. University of Missouri--Kansas City, 2004.
Typescript. "A dissertation in engineering and telecommunication networking." Advisor: Ghulam M. Chaudhry. Vita. Title from "catalog record" of the print edition Description based on contents viewed Feb. 23, 2006. Includes bibliographical references (leaves 150-158) and index. Online version of the print edition.

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Mohagheghi, Salman. "Adaptive Critic Designs Based Neurocontrollers for Local and Wide Area Control of a Multimachine Power System with a Static Compensator." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/16216.

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Modern power systems operate much closer to their stability limits than before. With the introduction of highly sensitive industrial and residential loads, the loss of system stability becomes increasingly costly. Reinforcing the power grid by installing additional transmission lines, creating more complicated meshed networks and increasing the voltage level are among the effective, yet expensive solutions. An alternative approach is to improve the performance of the existing power system components by incorporating more intelligent control techniques. This can be achieved in two ways: introducing intelligent local controllers for the existing components in the power network in order to employ their utmost capabilities, and implementing global intelligent schemes for optimizing the performance of multiple local controllers based on an objective function associated with the overall performance of the power system. Both these aspects are investigated in this thesis. In the first section, artificial neural networks are adopted for designing an optimal nonlinear controller for a static compensator (STATCOM) connected to a multimachine power system. The neurocontroller implementation is based on the adaptive critic designs (ACD) technique and provides an optimal control policy over the infinite horizon time of the problem. The ACD based neurocontroller outperforms a conventional controller both in terms of improving the power system dynamic stability and reducing the control effort required. The second section investigates the further improvement of the power system behavior by introducing an ACD based neurocontroller for hierarchical control of a multimachine power system. The proposed wide area controller improves the power system dynamic stability by generating optimal control signals as auxiliary reference signals for the synchronous generators automatic voltage regulators and the STATCOM line voltage controller. This multilevel hierarchical control scheme forces the different controllers throughout the power system to optimally respond to any fault or disturbance by reducing a predefined cost function associated with the power system performance.

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Kiran, Sai. "A Wideband Airport Pseudolite Architecture for the Local Area Augmentation System." Ohio University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1081191846.

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Sullivan, Anthony John. "Distributed control applications using local area networks: a LAN based power control system at Rhodes University." Thesis, Rhodes University, 2002. http://hdl.handle.net/10962/d1005246.

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This thesis describes the design and development of both the hardware and software of an embedded, distributed control system using a LAN infrastructure for communication between nodes. The primary application of this system is for power monitoring and control at Rhodes University. Both the hardware and software have been developed to provide a modular and scalable system capable of growing and adapting to meet the changing demands placed on it. The software includes a custom written Internet Protocol stack for use in the embedded environment, with a small code footprint and low processing overheads. There is also Linux-based control software, which includes a web-based device management interface and graphical output. Problems specific to the application are discussed as well as their solutions, with particular attention to the constraints of an embedded system.

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Zou, Xiaolan. "Frequency and Damping Characteristics of Generators in Power Systems." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/81937.

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A power system stability is essential for maintaining the power system oscillation frequency within a small and acceptable interval around its nominal frequency. Hence, it is necessary to study and control the frequency for stable operation of a power system by knowing the characteristics within a power system. One approach is to understand the effectiveness of frequency and damping characteristics of generators in power systems. Hence, the simulation analysis of IEEE 118-bus power system is used for this study. The analysis includes theoretical analysis with a mathematical approach and simulation studies of swing equation to determine the characteristics of damped single-machine infinite bus, which is represented as a generator connects to a large network system with a small signal disturbance by line losses. Additionally, mathematical derivation of Prony analysis is presented in order to estimate the frequency and damping ratio of the simulation results. In the end, the results demonstrate that the frequency and damping characteristics of generators are highly dependent on the system inertia constant. Therefore, the higher inertia constant is a critical factor to ensure the system is more stable.
Master of Science

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Bahadornejad, Momen. "On-line local load measurement based voltage instability prediction." Queensland University of Technology, 2005. http://eprints.qut.edu.au/16187/.

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Voltage instability is a major concern in operation of power systems and it is well known that voltage instability and collapse have led to blackout or abnormally low voltages in a significant part of the power system. Consequently, tracking the proximity of the power system to an insecure voltage condition has become an important element of any protection and control scheme. The expected time until instability is a critical aspect. There are a few energy management systems including voltage stability analysis function in the real-time environment of control centres, these are based on assumptions (such as off-line models of the system loads) that may lead the system to an insecure operation and/or poor utilization of the resources. Voltage instability is driven by the load dynamics, and investigations have shown that load restoration due to the on-load tap changer (OLTC) action is the main cause of the voltage instability. However, the aggregate loads seen from bulk power delivery transformers are still the most uncertain power system components, due to the uncertainty of the participation of individual loads and shortcomings of the present approaches in the load modeling. In order to develop and implement a true on-line voltage stability analysis method, the on-line accurate modeling of the higher voltage (supply system) and the lower voltage level (aggregate load) based on the local measurements is required. In this research, using the changes in the load bus measured voltage and current, novel methods are developed to estimate the supply system equivalent and to identify load parameters. Random changes in the load voltage and current are processed to estimate the supply system Thevenin impedance and the composite load components are identified in a peeling process using the load bus data changes during a large disturbance in the system. The results are then used to anticipate a possible long-term voltage instability caused by the on-load tap changer operation following the disturbance. Work on the standard test system is provided to validate the proposed methods. The findings in this research are expected to provide a better understanding of the load dynamics role in the voltage stability, and improve the reliability and economy of the system operation by making it possible to decrease uncertainty in security margins and determine accurately the transfer limits.

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Rowse, Tarah. "Local Energy Governance In Vermont: An Analysis Of Energy System Transition Strategies And Actor Capacity." ScholarWorks @ UVM, 2014. http://scholarworks.uvm.edu/graddis/257.

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While global, national, and regional efforts to address climate and energy challenges remain essential, local governments and community groups are playing an increasingly stronger and vital role. As an active state in energy system policy, planning and innovation, Vermont offers a testing ground for research into energy governance at the local level. A baseline understanding of the energy planning and energy organizing activities initiated at the local level can support efforts to foster a transition to a sustainable energy system in Vermont. Following an inductive, applied and participatory approach, and grounded in the fields of sustainability transitions, energy planning, and community energy, this research project identifies conditions for change, including opportunities and challenges, within Vermont energy system decision-making and governance at the local level. The following questions are posed: What are the main opportunities and challenges for sustainable energy development at the town level? How are towns approaching energy planning? What are the triggers that will facilitate a faster transition to alternative energy systems, energy efficiency initiatives, and localized approaches? In an effort to answer these questions two studies were conducted: 1) an analysis of municipal energy plans, and 2) a survey of local energy actors. Study 1 examined Vermont energy planning at the state and local level through a review and comparison of 40 municipal plan energy chapters with the state 2011 Comprehensive Energy Plan. On average, municipal plans mentioned just over half of the 24 high-level strategies identified in the Comprehensive Energy Plan. Areas of strong and weak agreement were examined. Increased state and regional interaction with municipal energy planners would support more holistic and coordinated energy planning. The study concludes that while municipalities are keenly aware of the importance of education and partnerships, stronger policy mechanisms and financial stimulus are essential if Vermont hopes to increase strategic energy planning alignment and spur whole-scale energy system change. Study 2 examined local energy actors to assess their ability to develop and sustain energy action on the local level. A survey of 120 municipalities collected statewide baseline data covering the structures, processes, and activities of local energy actors. The analysis examined the role that various forms of capacity play in local energy activity. The results show that towns with higher incomes are more likely to have local energy actors and towns with higher populations have higher aggregate energy activity levels. Structurally, energy actors that had both an energy coordinator and an energy committee were more active, and municipal committees were more active than independent committees. Access to a budget and volunteer engagement were both associated with higher activity levels. The network of local energy actors in Vermont consists of committed and knowledgeable volunteers. Yet, the capacity of these local energy actors to implement sustainable energy change is limited due to resource constraints of time and money. In most cases, the scope of municipal energy planning strategy is modest. Prioritization of strategy and action at the central and local levels, along with increased interaction and coordination, is necessary to increase the regional compatibility and pace of energy system transformation.

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Hermanus, Lauren. "Local governments' changing power in South Africa's energy system: reshaping the regulatory space for renewable energy, from the bottom up." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/25323.

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In 1994, South Africa's post-apartheid government inherited a highly-centralised energy sector, in which all aspects including planning, procurement, generation, distribution, pricing, and management were determined through top-down institutional arrangements and investments, centred around Eskom. In 2016, however, following rounds of energy sector reform, and the successful implementation of the Renewable Energy Independent Power Producers Procurement Programme (REIPPPP), this centralised configuration of power showed signs of disruption. Municipalities began to ambitiously redefine their role by building on opportunities related to renewable energy, resulting in an emergent challenge to centralised energy policy and planning. This dissertation sought to explore how this contestation took shape and to explain how seemingly ad hoc actions have created new possibilities, as well as new regulatory frameworks, by municipalities for municipalities. To achieve this, an analysis of the evolution of decentralised renewable energy generation in South Africa between 2008, when it first began, and 2016, was undertaken, applying the method of process tracing to two case studies. In order to contextualise these bottom-up processes within the national political economy of energy, process tracing was also applied in a high-level analysis of countervailing movements that consolidate centralised energy planning and procurement during the same period, with a particular focus on national plans to undertake massive investments in nuclear energy. It was found that municipalities' bottom-up actions have positioned them to drive renewable energy in such a way that seriously challenges the historical configuration of power that has determined South Africa's energy future up to now.

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Bernáth, František. "Rozptýlená výroba a jej vplyv na kvalitu dodávok elektrickej energie." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-233625.

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This work deals with the deployment of distributed power sources into the electric power grid. The nature of these sources causes that the massive integration may experience problems with power quality in the local context, and also overall reliability of supply in the range of interconnected power systems may be endangered. Work is focused on local voltage quality problems with special emphasis on analysis and design of tools (e.g. reactive power compensation units of power plants or dynamic voltage control by transformers 110/22kV) for voltage control in power distribution systems. These tools should be used as a part of uniform concept of voltage control. The proposed concept is involved.

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Martyr, Randall. "Optimal prediction games in local electricity markets." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/optimal-prediction-games-in-local-electricity-markets(976e566d-e942-444a-9ee0-df17f46188d4).html.

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Local electricity markets can be defined broadly as 'future electricity market designs involving domestic customers, demand-side response and energy storage'. Like current deregulated electricity markets, these localised derivations present specific stochastic optimisation problems in which the dynamic and random nature of the market is intertwined with the physical needs of its participants. Moreover, the types of contracts and constraints in this setting are such that 'games' naturally emerge between the agents. Advanced modelling techniques beyond classical mathematical finance are therefore key to their analysis. This thesis aims to study contracts in these local electricity markets using the mathematical theories of stochastic optimal control and games. Chapter 1 motivates the research, provides an overview of the electricity market in Great Britain, and summarises the content of this thesis. It introduces three problems which are studied later in the thesis: a simple control problem involving demand-side management for domestic customers, and two examples of games within local electricity markets, one of them involving energy storage. Chapter 2 then reviews the literature most relevant to the topics discussed in this work. Chapter 3 investigates how electric space heating loads can be made responsive to time varying prices in an electricity spot market. The problem is formulated mathematically within the framework of deterministic optimal control, and is analysed using methods such as Pontryagin's Maximum Principle and Dynamic Programming. Numerical simulations are provided to illustrate how the control strategies perform on real market data. The problem of Chapter 3 is reformulated in Chapter 4 as one of optimal switching in discrete-time. A martingale approach is used to establish the existence of an optimal strategy in a very general setup, and also provides an algorithm for computing the value function and the optimal strategy. The theory is exemplified by a numerical example for the motivating problem. Chapter 5 then continues the study of finite horizon optimal switching problems, but in continuous time. It also uses martingale methods to prove the existence of an optimal strategy in a fairly general model. Chapter 6 introduces a mathematical model for a game contingent claim between an electricity supplier and generator described in the introduction. A theory for using optimal switching to solve such games is developed and subsequently evidenced by a numerical example. An optimal switching formulation of the aforementioned game contingent claim is provided for an abstract Markovian model of the electricity market. The final chapter studies a balancing services contract between an electricity transmission system operator (SO) and the owner of an electric energy storage device (battery operator or BO). The objectives of the SO and BO are combined in a non-zero sum stochastic differential game where one player (BO) uses a classic control with continuous effects, whereas the other player (SO) uses an impulse control (discontinuous effects). A verification theorem proving the existence of Nash equilibria in this game is obtained by recursion on the solutions to Hamilton-Jacobi-Bellman variational PDEs associated with non-zero sum controller-stopper games.

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Hertzog, Patrick. "Gestion des réseaux locaux industriels : application au réseau." Nancy 1, 1994. http://www.theses.fr/1994NAN10047.

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Ce mémoire aborde la nouvelle administration du réseau local industriel factor. A la suite d'une enquête menée sur les besoins en administration exprimés par les utilisateurs, nous avons réalisé une étude bibliographique sur la gestion de réseau afin de connaitre l'état de l'art en terme de normalisation et de produits. Après une présentation des généralités et particularités de ce réseau, nous montrons les différentes phases suivies pour des raisons technologiques et économiques. La première a porté sur l'étude et le développement de factor view, dans l'intention de répondre rapidement aux attentes des clients. La deuxième a porté sur la nouvelle administration du réseau factor intégrant l'ouverture à l'administration basée sur le protocole SNMP (simple network management protocol). Afin de remonter au niveau SNMP l'ensemble des informations disponible sur le réseau, nous présentons une méthode orientée objet destinée à permettre le développement d'une MIB (management information base) privée

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Lecuire, Vincent. "Gestion des systèmes et réseaux industriels." Nancy 1, 1994. http://www.theses.fr/1994NAN10051.

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Le réseau local industriel est devenu une composante essentielle des systèmes automatisés de production. Mais il peut être source, tant de non-productivité que de cout si sa fiabilité, sa maintenabilité, sa sécurité et ses performances ne sont pas garanties. C'est pourquoi la gestion de réseau cruciale dans un tel environnement. Toutefois, elle ne constitue pas une finalité en soi, et les besoins fonctionnels de l'utilisateur final sont plus diversifiés. Dans ce mémoire, un modèle de gestion des systèmes et réseaux industriels est proposé. Il tient compte de l'hétérogénéité culturelle des différents intervenants, c'est-à-dire de leur préoccupation et de leur savoir-faire. Le modèle présenté se base et tire profit de la normalisation relative à la gestion OSI dont il reconsidère et élargit le champ d'applications. Les systèmes et le réseau formant le support des applications distribuées, l'intégration de ces deux composantes indissociables au sein d'un unique modèle permet, dans une stratégie globale, de gérer finalement la partie commande du point de vue de son organisation. Enfin, une méthodologie orientée-objet guide l'analyse et la conception de l'activité de gestion, depuis l'expression des besoins des utilisateurs jusqu'a la solution définie en termes d'objets gérés et de coopération entre les processus distribués

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Büchner, Stefan. "Energiemanagement Strategien für elektrische Energiebordnetze in Kraftfahrzeugen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1228736572957-56492.

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Die elektrische Energieform gewinnt im Kraftfahrzeug wegen ihrer Nutzungsvielfalt und sehr guten Steuerbarkeit für die Realisierung neuartiger Funktionen zunehmend an Bedeutung. Voraussetzung für ihren Einsatz ist eine zuverlässige und effiziente Bereitstellung durch das Kfz-Energiebordnetz. Dafür ist ein intelligentes Energiemanagement erforderlich, welches mit geeigneten Strategien die Leistungsflüsse im Energiesystem koordiniert. In dieser Arbeit werden die beiden Entwurfsziele der Zuverlässigkeit und der Effizienz bei der Entwicklung von elektrischen Energiemanagement-Strategien systematisch betrachtet. Es erfolgt eine Beschreibung und Zuordnung der einzelnen Ziele und Maßnahmen anhand der Energieflüsse und Wirkungsketten. Ein Schwerpunkt bildet dabei die Beherrschung von Lastwechseln im Bordnetz. Für Aussagen hinsichtlich einer effizienten Erzeugung elektrischer Energie erfolgt eine Untersuchung der Energiewandlungskette anhand analytischer Methoden und mit Hilfe einer simulationsgestützten Optimierung. Ein weiterer Fokus der Arbeit liegt in der Betrachtung zur Anwendung ökonomischer Modelle für eine Energiekoordination. Es werden die theoretischen Grundlagen der Mikroökonomie zusammengestellt und mögliche Funktionsstrukturen eines einseitigen und zweiseitigen Allokationsmechanismus verglichen und bewertet. Abschließend zeigen experimentelle Untersuchungen an einem Bordnetzprüfstand zum Lastwechselverhalten und die Integration eines Energiemanagement-Systems den praktischen Bezug zum realen System.

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Ala-Mutka, Jonatan. "Powering Africa by Empowering its People : An Action Research study at a Zambian microgrid company building local capacity to reach large scale viability." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-261596.

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Despite recent advances in the global electrification rates, increasing from 76% in 1990 to 85% in 2012, the United Nations goal of universal access to electricity by 2030 is still far from achieved, with an estimated 1.1 billion people still without access to electricity. Over half of these live in Sub-Saharan Africa, with a majority in rural areas and extreme poverty. Major challenges are inert with the current electrification path of centralized grid extension, leaving these people without power in decades to come. Microgrids, a decentralized power system consisting of solar power generation, energy storage and distribution technology, has been hailed as the only option to provide life improving and productivity inducing power for rural communities in Africa. However, despite recent hype and development in the sector, the diffusion of microgrids is still incremental due to a lack of viable large-scale operation, required for profitability. This is explained by targeting customers in remote rural areas with low ability to pay, and the task of delivering expensive technology and complex operations needed to manage and operate the grids. No industry blueprint or research on how to operate microgrids at scale or profitably exists. This thesis explores one blueprint, with the promise to increase profitability and allow for a more sustainable scaling. Local Capacity building is a decentralized approach by developing capacity directly in the local communities, through recruiting, skills development and training of people to be employed to operate and manage their local microgrids. The results consist of a framework outlining what local capacity building is, through research propositions that define the key components capturing the complete system of local capacity building is for scaling a microgrid business, along with the challenges and opportunities associated with scaling a business using local capacity building. It has been developed iteratively by application of an action research approach conducted on a small-scale Zambian Microgrid company facing radical growth. The researcher was immersed in the context, at the heart of this change, and in a participatory and interventionist fashion turning every stone to explore what local capacity building is, resulting in a robust study anchored in the field. Because of the contextually embedded nature of the data, this also means that the results are local. It is up to the reader to assess the applicability of the results in another context. The extensive results span multiple areas of the business, capturing the complexity of local capacity building, and contribute to knowledge on a holistic level on what local capacity building is. This blueprint was deemed viable to further develop in the small-scale Zambian microgrid company, specifically because of its potential to lower operating expenses and offer a more sustainable way to scale, and in extension diffuse microgrids in Africa.
Trots en positiv utveckling i tillgång till el globalt, ökandes från 76% år 1990, till 85% år 2012, så är Förenta Nationernas mål om universell tillgång till el till år 2030, långt ifrån att bli uppfyllt. 1.1 miljarder människor estimeras vara utan tillgång till el globalt, där över hälften av dessa bor i Sub-Saharanska Afrika, med majoriteten levandes på landsbygden och i extrem fattigdom. Stora utmaningar finns med innevarande elektrifierings strategin, som handlar om centraliserad elproduktion och distribution genom ett centralt elnät, detta kommer att lämna dessa människor utan el under lång tid framöver. Mikronät, ett decentraliserat energisystem, som kan producera och distribuera el, har lyfts fram som det bästa alternativet för att försörja livsförbättrande och produktivitetsökande elektricitet för samhällen på landsbygden i Afrika. Dock, trots nylig hype och utveckling i mikronät sektorn, så är spridningen av mikronät fortfarande inkrementell, beroende av en brist på genomförbarheten av att driva mikronät verksamheten i stor skala, vilket krävs för lönsamhet. Detta förklaras av den fundamentala utmaningen i att inrikta sig mot kunder i avlägsna områden, med en låg förmåga att betala, kombinerat med leveransen av dyr teknologi, och de komplex operativa strukturerna som krävs. Det finns ingen forskning eller blåkopia i industrin som visar hur man skulle kunna bedriva mikronäts verksamhets i stor skala, eller på ett lönsamt vis. Denna forskning undersöker en möjlig sådan blåkopia, med löftet att öka lönsamheten och möjliggöra en mer hållbar spridning. Utveckling av lokal kapacitet, är ett decentraliserat tillvägagångssätt för att utveckla kapacitet direkt i dessa avlägsna samhällen, genom rekrytering, färdighetsutveckling och utbildning av människor för att bli anställda för att sköta deras lokala mikronät. Resultaten i studien består av ett ramverk som visar vad utveckling av lokal kapacitet innebär, genom forskningsförslag som definierar vilka nyckelkomponenter som krävs för att skala upp en mikronäts verksamhet, tillsammans med utmaningar och möjligheter för att göra detta. Ramverket har utvecklats iterativt genom applicering av Action Research, utförd i ett småskaligt mikronät företag i Zambia som står inför en radikal expansion. Forskaren var fördjupad i företagskontexten, i hjärtat av förändringen, och på ett ingripande och deltagande sätt vänt på varenda sten för att utforska vad utveckling av lokal kapacitet är. Detta resulterade i en robust studie, förankrad i verkligheten. På grund av den kontextuellt inbäddade naturen av datan, så betyder detta även att resultaten är lokala. Det är upp till läsaren att bedöma till vilken grad resultaten kan appliceras i en annan kontext. De omfattande resultaten spänner över många olika områden i företaget, och lyckas fånga komplexiteten i vad utveckling av lokal kapacitet är. Blåkopian som utvecklades, bedömdes värdefull att utveckla vidare i företaget där studien gjorde, specifikt för dess potential att minska de operativa kostnaderna och erbjuda ett mer hållbart sätt att skala verksamheten, och i förlängningen, erbjuda ett mer hållbart sätt att sprida tillgång till el i Afrika.

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Olivella, Rosell Pol. "Local electricity markets design and operation in distribution power systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/669803.

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In the context of distributed generation growth, local grids could face operational issues. In that sense, smart grid deployment will give information to local grid operators about grid status at medium and low voltage levels for taking operational decisions on daily basis. This thesis presents local markets as a potential solution to avoid local grid congestions and over-costs. They mainly increase the negotiation power of end-users with distributed energy resources and allow activation of flexibility at local level. First of all, this thesis analyses electric vehicles as a potential challenge for distribution grids and electricity markets in case of uncontrolled charging as it could cause consumption peaks. At the same time, electric vehicles could be part of the solution thanks to their capability of shifting forward their consumption. The first solution presented in this thesis is a building level electric vehicle management algorithm in order to reduce energy cost and consumption peaks. However, local grid operators need a solution to deal with aggregated level problems like high demand or high generation periods. Such kind of problems vary over time and place, and they could be difficult to integrate in regular grid tariffs. Therefore, the present thesis provides two local market designs for these problems. The first local market presented is designed for taking advantage of renewable energy producers before and after the whole-sale day-ahead market without threatening distribution grids and increasing the local social welfare. However, this market implies significant regulatory changes because the local market operator should take sorne of the current local grid operator regulated activities. Therefore, this thesis presents a second market design for managing portfolios of consumers, producers and prosumers, and it could be operated by retailers, balance responsible parties or aggregators for flexibility provision without regulatory issues. The work includes a description of roles, contracts and interactions of such local flexibility market, and three optimization algorithms depending on the application, complexity and portfolio scale. The first algorithm assumes limited information about each site, the second one includes such information but presents potential scalability limitations, and the last algorithm is based on a decomposition method to optimise the aggregator portfolio in a distributed way reducing the computational burden and time.
En el context d'expansió de generadors d'electricitat renovable i distribuïda, les xarxes de distribució podrien presentar problemes d'operació. A més a més, en un context de desplegament de la xarxa elèctrica intel·ligent, les companyies distribuïdores tindran un millor coneixement de l'estat de la xarxa per prendre decisions d'operació en el dia a dia tant a nivell de mitja com en baixa tensió. Els mercats locals constitueixen una possible solució per a la resolució de congestions a les xarxes de distribució d'electricitat i reduir els sobre costos del sistema elèctric. Aquests mercats també permetrien incrementar el poder de negociació dels consumidors d'electricitat a petita escala amb capacitat de flexibilitat. Primerament s'analitza el potencial perill que poden suposar els vehicles elèctrics per a les xarxes de distribució en cas de no haver-hi gestió intel·ligent dels processos de carrega ja que podrien aparèixer nous pics de consum. Alhora, els vehicles elèctrics podrien ser part de la solució desplaçant el seu consum a la nit. El present treball inclou un algorisme de gestió de vehicles elèctrics a nivell d'edifici per a reduir el cost d'electricitat i els pics de consum. No obstant, les companyies distribuïdores necessiten una solució per als problemes de la xarxa que podrien ser diferents segons la zona o l'època de l'any. Es per això que aquest treball inclou dues propostes de mercat local per a aquests problemes. El primer mercat local esta dissenyat per a aprofitar l'avantatge dels productors d'energia renovable abans i després del mercat diari majorista sense comprometre l'operació de la xarxa de distribució. Tot i aixó, aquesta proposta de mercat local requeriria diversos canvis en matèria de regulació ja que l'operador del mercat local hauria de prendre algunes de les actuals responsabilitats de les companyies distribuïdores. Seguidament, la tesi presenta un segon mercat local per gestionar una cartera de consumidors, productors i prosumidors, com una activitat més dins de les activitats de les companyies comercialitzadores o agregadors de flexibilitat. El present document inclou una descripció dels rols, contractes i interaccions, i tres algorismes d'optimització des del més simple fins al més complex. El primer assumeix una limitació en la informació disponible de cada membre de la cartera, el segon inclou més informació però presenta limitacions d'escalabilitat, i finalment el tercer presenta un algorisme de descomposició per optimitzar la flexibilitat de manera distribuïda i així reduir el temps de computació i la complexitat de càlcul.

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Rivière, Mylène. "Les (dé)connexions du développement : ethno-géographie systémique de l'aide au développement et à la conservation forestière à Amindrabe, Madagascar." Thesis, Bordeaux 3, 2017. http://www.theses.fr/2017BOR30029/document.

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Cette recherche part du constat d'un dysfonctionnement de l'aide au développement et à la conservation. Depuis les années 1980 et malgré la succession des stratégies de l'aide, les résultats restent souvent insatisfaisants, médiocres, voire contraires aux effets recherchés. Pour comprendre ce phénomène, nous partons d'un territoire forestier, Amindrabe, situé au Centre-Est de Madagascar. En nous focalisant sur ce territoire, ses habitants et les programmes d'aide qui le ciblent, nous prenons progressivement conscience des logiques sous-jacentes à ce système global du développement : qu'est-ce qui s'y passe concrètement ? Comment est-ce organisé ? Pourquoi ces dynamiques se poursuivent-elles malgré des effets décevants ? La singularité de notre proposition est de nous détacher de la littérature surplombante pour partir du perçu et du vécu des habitants et des porteurs des programmes. Cette analyse empirique et qualitative amène à poser un regard critique sur les croyances fondatrices des stratégies de l'aide. Nous mettons en lumière une organisation hiérarchisée et compartimentée en différentes sphères déconnectées entre elles et déconnectées de la réalité locale. Les croyances, illusions et intérêts de chacun participent à renforcer l'incompréhension entre sphères et à détourner les actions des objectifs initiaux, par un processus qui se répète. En décortiquant un système d'acteur particulier, ses mondes et ses dynamiques du local au global, nous invitons le lecteur à un plongeon au-delà de ces incompréhensions
This research is based on the observation of a dysfunction in aid for development and conservation. Since the 1980s and despite the succession of aid strategies, the results are often unsatisfactory, mediocre or even contrary to the desired effects. To understand this phenomenon, we begin in a forest territory, Amindrabe, located in the Central-East of Madagascar. By focusing on this territory, its inhabitants and the aid programs that target it, we gradually become aware of the underlying logic of this global development system: what is actually happening there? How is it organized? Why do these dynamics go on despite disappointing effects? The singularity of our proposal is to detach ourselves from the overhanging literature to start with the perceived experiences of the inhabitants and the bearers of the programs. This empirical and qualitative analysis leads us to take a critical look at the founding beliefs of aid strategies. We highlight a hierarchical and compartmentalized organization in different spheres: disconnected from each other and disconnected from the local reality. The beliefs, illusions and interests of each actor contribute to reinforce the incomprehension between spheres and to divert the actions from the initial objectives by a process that repeats itself. By anatomizing a particular actor system, its worlds and its dynamics from local to global, we invite the reader to a dive beyond these incomprehensions

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Al-Khaykan, Ameer. "Controller design methodology for sustainable local energy systems." Thesis, University of Chester, 2018. http://hdl.handle.net/10034/621613.

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Commercial Buildings and complexes are no longer just national heat and power network energy loads, but they are becoming part of a smarter grid by including their own dedicated local heat and power generation. They do this by utilising both heat and power networks/micro-grids. A building integrated approach of Combined Heat and Power (CHP) generation with photovoltaic power generation (PV) abbreviated as CHPV is emerging as a complementary energy supply solution to conventional (i.e. national grid based) gas and electricity grid supplies in the design of sustainable commercial buildings and communities. The merits for the building user/owner of this approach are: to reduce life time energy running costs; reduce carbon emissions to contribute to UK’s 2020/2030 climate change targets; and provide a more flexible and controllable local energy system to act as a dynamic supply and/or load to the central grid infrastructure. The energy efficiency and carbon dioxide (CO2) reductions achievable by CHP systems are well documented. The merits claimed by these solutions are predicated on the ability of these systems being able to satisfy: perfect matching of heat and power supply and demand; ability at all times to maintain high quality power supply; and to be able to operate with these constraints in a highly dynamic and unpredictable heat and power demand situation. Any circumstance resulting in failure to guarantee power quality or matching of supply and demand will result in a degradation of the achievable energy efficiency and CO2 reduction. CHP based local energy systems cannot rely on large scale diversity of demand to create a relatively easy approach to supply and demand matching (i.e. as in the case of large centralised power grid infrastructures). The diversity of demand in a local energy system is both much greater than the centralised system and is also specific to the local system. It is therefore essential that these systems have robust and high performance control systems to ensure supply and demand matching and high power quality can be achieved at all times. Ideally this same control system should be able to make best use of local energy system energy storage to enable it to be used as a flexible, highly responsive energy supply and/or demand for the centralised infrastructure. In this thesis, a comprehensive literature survey has identified that there is no scientific and rigorous method to assess the controllability or the design of control systems for these local energy systems. Thus, the main challenge of the work described in this thesis is that of a controller design method and modelling approach for CHP based local energy systems. Specifically, the main research challenge for the controller design and modelling methodology was to provide an accurate and stable system performance to deliver a reliable tracking of power drawn/supplied to the centralised infrastructure whilst tracking the require thermal comfort in the local energy systems buildings. In the thesis, the CHPV system has been used as a case study. A CHPV based solution provides all the benefits of CHP combined with the near zero carbon building/local network integrated PV power generation. CHPV needs to be designed to provide energy for the local buildings’ heating, dynamic ventilating system and air-conditioning (HVAC) facilities as well as all electrical power demands. The thesis also presents in addition to the controller design and modelling methodology a novel CHPV system design topology for robust, reliable and high-performance control of building temperatures and energy supply from the local energy system. The advanced control system solution aims to achieve desired building temperatures using thermostatic control whilst simultaneously tracking a specified national grid power demand profile. The theory is innovative as it provides a stability criterion as well as guarantees to track a specified dynamic grid connection demand profile. This research also presents: design a dynamic MATLAB simulation model for a 5-building zone commercial building to show the efficacy of the novel control strategy in terms of: delivering accurate thermal comfort and power supply; reducing the amount of CO2 emissions by the entire energy system; reducing running costs verses national rid/conventional approaches. The model was developed by inspecting the functional needs of 3 local energy system case studies which are also described in the thesis. The CHPV system is combined with supplementary gas boiler for additional heating to guarantee simultaneous tracking of all the zones thermal comfort requirements whilst simultaneously tracking a specified national grid power demand using a Photovoltaics array to supply the system with renewable energy to reduce amount of CO2 emission. The local energy system in this research can operate in any of three modes (Exporting, Importing, Island). The emphasise of the thesis modelling method has been verified to be applicable to a wide range of case studies described in the thesis chapter 3. This modelling framework is the platform for creating a generic controlled design methodology that can be applied to all these case studies and beyond, including Local Energy System (LES) in hotter climates that require a cooling network using absorption chillers. In the thesis in chapter 4 this controller design methodology using the modelling framework is applied to just one case study of Copperas Hill. Local energy systems face two types of challenges: technical and nontechnical (such as energy economics and legislation). This thesis concentrates solely on the main technical challenges of a local energy system that has been identified as a gap in knowledge in the literature survey. The gap identified is the need for a controller design methodology to allow high performance and safe integration of the local energy system with the national grid infrastructure and locally installed renewables. This integration requires the system to be able to operate at high performance and safely in all different modes of operation and manage effectively the multi-vector energy supply system (e.g. simultaneous supply of heat and power from a single system).

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Zhu, Lei. "Advanced local prediction and its applications in power and energy systems." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/2007714/.

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Due to the global energy crisis and environmental concerns, the development of sustainable energy is considered by more and more countries. In order to make this target, energy demand management is significantly necessary in which forecasting the energy demand is the starting point. The accurate prediction of energy demand could help the energy sectors to make these operation decisions and policy properly. A novel approach, which is the support vector regression based local predictor with false neighbor filtered (FNF-SVRLP), is proposed. This method is an amelioration of the support vector regression based local predictor (SVRLP). SVRLP is a powerful prediction method which employs phase reconstruction algorithms, such as the correlation dimension and mutual information methods used in time series analysis for data preprocessing. Compared with the global prediction method, in a local prediction method, each predicting point has its own model constructed based on its nearest neighbors (NNs) reconstructed from the time series, and the fitness of NNs would mainly affect the model performance. However, it has been found that NNs may contain a class of false neighbors (FNs) which would decrease the fitting accuracy dramatically and lead to a poorer forecasting performance. Therefore, a new false neighbor filter is proposed to remove those false neighbors and keep the optimal nearest neighbors. Then, the FNF-SVRLP is proposed. Wind power is one of the most popular renewable energy. The increasing penetration of wind power into the electric power grid accompanied with a series of challenges. Due to the uncertain and variable nature of wind resources, the output power of wind farms is hard to control, which could lead to the instability of the power grid operation and the unreliability of electricity supplies. In order to slove this problem, the FNF-SVRLP based short-term wind power perdition model is presented. Through the comparison with the SVRLP based short-term wind power perdition and ARMA based short-term wind power perdition, it is found that the FNF-SVRLP based short-term wind power perdition model is much more accurate than the others. Due to the fact that natural gas is cleanest burning of all fossil fuel, it can be considered as an important adjunct to renewable energy sources such as wind or solar, as well as a bridge to the new energy economy. Different from the wind power, the customer consumption behavior could effect the natural gas demand. Therefore, the customer behavior based ``Advanced Model" with FNF-SVRLP is presented to undertake the natural gas prediction. The proposed FNF-SVRLP natural gas model is compared with the SVRLP and autoregressive moving average (ARMA) to show its superiority. In addition, a web sever based online natural gas demand perdition system has been set up to help the National Grid to obtain the accurate daily natural gas demand perdition easily and timely. It is found that the most kinds of energy demand data are non-stationary, the internal regularity between predicting point and its nearest-neighbors are much more complex than the stationary dataset. In order to help the local predictor to capture the internal regularity between predicting point and its nearest-neighbors more accurately, the morphological filter is proposed. the morphological filter is applied to decompose the non-stationary dataset into several subsequences, ranked form the low frequency subsequence to the high frequency subsequence. Through this way, the local predictor could capture the non-stationary dataset more accurate, and improve the final performance of prediction. The morphological filter is applied to decompose the non-stationary into several subsequences, ranked form the low frequency subsequence to the high frequency subsequence. Through this way, the local predictor could capture the non-stationary dataset more accurate, and improve the final performance of prediction. Moveover, an novel calculation method of structure element (SE) is introduced. Different form the conventional SE, this novel approach can optimize the scale and shape of SE to match the original signal. After that, a novel algorithm, which is mathematical morphology based local prediction with support vector regression (SVRLP-MM) is proposed. The real-world wind speed data has been used to evaluate the performance of SVRLP-MM. The final results presented demonstrate that SVRLP-MM based wind speed prediction model can achieve a higher prediction accuracy than the SVRLP based model and ARMA model based model by using the same real-world wind speed data.

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Sethuraman, Balasubramanian. "Novel Methodologies for Efficient Networks-on-Chip Implementation on Reconfigurable Devices." Cincinnati, Ohio : University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?ucin1196043683.

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Thesis (Ph. D.)--University of Cincinnati, 2007.
Advisor: Ranga Vemuri. Title from electronic thesis title page (viewed Feb. 18, 2008). Keywords: Networks-on-Chip (NoC), System-on-Chip (SoC), FPGA, Reconfigurable & Platform-Based Design, Light Weight Router Design, Multi Local Port Router, Multicast Router, Low Power Topology Generation & Mapping, Power Issues and IR drop Analysis, Minimum. Includes abstract. Includes bibliographical references.

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Netto, Ulisses Chemin. "Determinação de um parâmetro para monitoramento do desempenho de mensagens GOOSE do padrão IEC 61850 utilizadas em subestações de energia elétrica." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18154/tde-16102012-083711/.

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O desenvolvimento e utilização do padrão IEC 61850 alterou a concepção e operação das subestações de energia elétrica. O desempenho e confiabilidade do sistema de proteção depende da rede de comunicação de dados. Esta pesquisa propõe um parâmetro de dimensionamento e comparação de desempenho para o tempo de transferência das mensagens Generic Object Oriented Substation Event (GOOSE) entre Intelligent Electronic Devices (IEDs). Esse parâmetro foi obtido através do levantamento experimental da curva do tempo de transferência das mensagens GOOSE versus a ocupação percentual da largura de banda dos IEDs. Para a realização dos experimentos foram utilizados três IEDs, um switch Ethernet gerenciável, três microcomputadores do tipo PC, um relógio sincronizador Global Positioning System (GPS), cordões de fibra óptica, cabos do tipo par trançado sem blindagem e aplicativos de software. Os resultados mostraram que a partir de um limiar característico, o qual é distinto para cada IED ensaiado, o tempo de transferência excede o limite máximo permitido pelo padrão IEC 61850. A partir da análise destes dados, foi desenvolvido um sistema preditivo de monitoramento de banda para supervisionar a interface de rede dos IEDs. O sistema preditivo apresentou para a medição de banda um erro relativo médio igual a 0,55% em relação ao aplicativo comercial utilizado na comparação, já a predição feita pela rede neural artificial apresentou um erro de estimativa menor do que 3% para 91,30% das amostras utilizadas, além de modelar adequadamente o comportamento da série temporal que representa a ocupação de banda do IED monitorado.
The development and utilization of IEC 61850 standard changed the design and operation of electric power substations. The performance and reliability of the protection system depends on the data communication network. This research proposes a parameter for dimensioning and comparising the transfer time of Generic Object Oriented Substation Event (GOOSE) messages between different Intelligent Electronic Devices (IEDs). This parameter was obtained from experimental data related to the transfer time of GOOSE messages curve versus IEDs bandwidth percentage occupation. In this context, a laboratory structure was set up in order to carry out these experiments. This structure mainly consists of three IEDs, an Ethernet switch, three personal computers, a GPS Clock, fiber optic cables, unshielded twisted pair cables, as well as support software. The results show the existence of a characteristic threshold, different for each IED tested, after which the transfer time exceeded the total transmission time allowed for the IEC 61850 standard. Based on these results, a predictive bandwidth monitoring system was developed to supervise the IEDs bandwidth interface. The bandwidth measurement has a mean relative error of 0.55% regarding to the commercial software used for comparison. Finally, the forecasting made by the artificial neural network has a relative error of 3% for 91,30% of the samples used in test phase. In addition, that it was able to model the behaviour of the time series that represent the bandwidth occupation.

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Hermansson, Helena. "Centralized Disaster Management Collaboration in Turkey." Doctoral thesis, Uppsala universitet, Statsvetenskapliga institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-319273.

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Following unprecedented earthquakes in 1999, highly centralized Turkey initiated reforms that aimed to improve disaster management collaboration and to empower local authorities. In 2011, two earthquakes hit the country anew affecting the city of Van and town of Erciş in Turkey’s southeast. In attempts to reduce disaster risk, global disaster risk reduction frameworks and disaster scholars and practitioners advocate collaborative and decentralized disaster management strategies. This thesis investigates how such strategies are received in a centralized and hierarchical national political-administrative system that largely is the anti-thesis of the prescribed solutions. More specifically, this research investigates the barriers and prerequisites for disaster management collaboration between both public and civil society actors in Turkey (during preparedness, response, and recovery) as well as how Turkey’s political-administrative system affects disaster management collaboration and its outcomes. The challenges to decentralization of disaster management are also investigated. Based on forty-four interviews with actors ranging from national to village level and NGOs, the findings suggest that the political-administrative system can alter the relative importance, validity, and applicability of previously established enabling or constraining conditions for collaboration. This may in turn challenge previous theoretical assumptions regarding collaboration. By adopting a mode of collaboration that fit the wider political-administrative system, collaborative disaster management progress was achieved in Turkey’s national level activities. Although there were exceptions, collaboration spanning sectors and/or administrative levels were generally less forthcoming, partly due to the disjoint character of the political-administrative system. Political divergence between local and central actors made central-local collaboration difficult but these barriers were partly trumped by other prerequisites enabling collaboration like interdependence and pre-existing relations. The findings suggest that the specific attributes of disasters may both help and hinder disaster management collaboration. Such collaboration generally improved disaster response. The findings also indicate that the decentralization attempts may have been premature as the conditions for ensuring a functional decentralization of disaster management are presently lacking. Decentralization attempts are commonly suggested to increase local capacity and local participation but the findings of this dissertation suggest that in Turkey, these commodities may currently have better chances of being increased by refraining from decentralization.

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Bleu, Jean-Jacques. "Réseaux de télécommunication en productique : Application, intégration paramètrée des communications pour le pilotage d'ateliers flexibles." Nancy 1, 1987. http://www.theses.fr/1987NAN10371.

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La conduite d'ateliers flexibles est assurée par un système informatique exécutant les instructions d'un logiciel de pilotage. Les équipements hétérogènes de production commandes en général par un ordinateur doivent échanger des informations sur un réseau de télécommunication

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Bukhsh, Waqquas Ahmed. "Islanding model for preventing wide-area blackouts and the issue of local solutions of the optimal power flow problem." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/9671.

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Optimization plays a central role in the control and operation of electricity power networks. In this thesis we focus on two very important optimization problems in power systems. The first is the optimal power flow problem (OPF). This is an old and well-known nonconvex optimization problem in power system. The existence of local solutions of OPF has been a question of interest for decades. Both local and global solution techniques have been put forward to solve OPF problem but without any documented cases of local solutions. We have produced test cases of power networks with local solutions and have collected these test cases in a publicly available online archive (http://www.maths.ed.ac.uk/optenergy/LocalOpt/), which can be used now by researchers and practitioners to test the robustness of their solution techniques. Also a new nonlinear relaxation of OPF is presented and it is shown that this relaxation in practice gives tight lower bounds of the global solution of OPF. The second problem considered is how to split a network into islands so as to prevent cascading blackouts over wide areas. A mixed integer linear programming (MILP) model for islanding of power system is presented. In recent years, islanding of power networks is attracting attention, because of the increasing occurrence and risk of blackouts. Our proposed approach is quite flexible and incorporates line switching and load shedding. We also give the motivation behind the islanding operation and test our model on variety of test cases. The islanding model uses DC model of power flow equations. We give some of the shortcomings of this model and later improve this model by using piecewise linear approximation of nonlinear terms. The improved model yields good feasible results very quickly and numerical results on large networks show the promising performance of this model.

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Tinarwo, Loyd. "Development of methodologies for deploying and implementing local & medium area broadband PLC networks in office and residential electric grids." Thesis, University of Fort Hare, 2008. http://hdl.handle.net/10353/83.

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The use of electrical networks for telecommunications has a long history. It has been known since the beginning of the twentieth century [Ahola03]. The idea of using electrical networks for broadband communications arose in the 1990s [Hrasnica et al 04]. Recent and growing research interest has indicated that PowerLine Communications (PLC) is the threshold for achieving broadband delivery particularly in very dispersed and low teledensity areas. Currently, there are numerous PLC trials and commercial deployments underway inside and outside South Africa. Nevertheless, these PLC deployments are very isolated, done without clear methodology and performance remains bound to the physical layout of the electrical network. Because of that high bandwidth broadband PLC systems are prone to poor performance and this in turn limits the acceptance and deployment of this emerging alternative broadband technology. Though, PLC technical challenges are being addressed, there has been little analysis and research work that is focused on the “Development of Methodologies for Deploying and Implementing Local & Medium Area Broadband Power Line in Residential and Office Electric Grids” that would lead to broadband PLC being adopted and be of greater use to non-broadband communities of South Africa. PLC is a term describing several different systems using electrical grid distribution wires for simultaneous distribution of data by superimposing an analog signal [Hrasnica et al 04]. The research proposed and presented broadband PLC methodologies for typical medium voltage and local voltage PLC networks. These methodologieswere implemented and experimented with in configurations which closely mirrored residential and office settings through laboratory and multibuilding experiments using commercial 2nd Generation Mitsubishi Electric PLC technology. Research results presented not only serve to provide insight into broadband PLC but also how it handled broadband applications (communications), competed and compared with other technologies such as Ethernet LAN. In combination with networking communication theories, the research explored and analyzed the extent of PLC in providing broadband communication to residential and office electric grids at the University Fort Hare, Computer Science Department.

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Lundqvist, Viktor. "Självförsörjande elgenerering : Kan Orust bli självförsörjande på förnybar el?" Thesis, Uppsala universitet, Elektricitetslära, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-242746.

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Orust Kretsloppsakademi is a nonprofit organisation, with a goal of annually generate the same amount of electrical energy that is consumed. Orust is an island on the west coast of Sweden, north of Gothenburg. The population of 15 000 reaches 40 000 during summer, due to the large amount of vacationer. The total electricity demand is 174 GWh a year with a maximum power need of 32 MW. This report presents an analysis for the plausibility of their plan and from a power system stability perspective, the effects on the electrical grid. The conclusion is that the restraints for development of power generation from wind, solar and wave generation, are the power systems capability to transfer power, primarily in the transformers of the grid. Various actions, such as constraints of power output at certain times, and clever location of generation facilities, reduces the utilisation rate of the line segments. In order to substantially decrease the utilisation rate of the line segments, the actions need to be combined. Executed simulations showed that Orust needs to be provided with reactive power, even if Orust is self-sufficient of active power, through its connection to the Swedish power system. The need for reactive power decreased when the feeding transformer allowed a reduced voltage in the regional network. Additionally, generation of reactive power could further increase the possibility for Orust to become self-sufficient on electricity generation.

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Schuhmann, Robert A. "The Constitution and the council-manager plan : public administration operating under a system without shared powers /." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08232007-113057/.

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Gaassand, Margrethe. "Women’s representation in spaces of participation and power : A study of tribal and non-tribal women in local systems of governance in Orissa, India." Thesis, Norges teknisk-naturvitenskapelige universitet, Geografisk institutt, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-17042.

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This study investigates the real representation of women in two villages in Orissa, India. Through my own feminist lens I have brought in theory of spaces of participation and power and hence linked this to the concept of real participation. Women from three different ranges within the local social hierarchies have participated in this study by sharing their knowledge, and I have tried to connect their stories and knowledge to political geography by captivating how they are represented in local governance. Representation is an important concept throughout this study, and it concerns how people feel that their interests are being represented and listened to. The study reveals women’s constrains and enabling factors to participate in formal or public spaces of governance. The studied women show that they lack real access to the invited spaces of participation in their local villages and thus they lack access to real representation through public spaces. This study also investigates the links between different spaces of representation, and shows that real representation is vital in women’s lives. When in practice excluded from the local public spaces of governance, these women claim spaces of participation and power by creating their own spaces of representation in the counter-publics.

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Ribeiro, Ricardo Luiz Mendes. "A decadência longe do poder: refundação e crise do PFL." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/8/8131/tde-14022013-100548/.

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Esta dissertação tem como objetivo analisar o processo de refundação do Partido da Frente Liberal (PFL), que resultou na troca de comando do partido e na substituição da denominação anterior da legenda por Democratas (DEM), em março de 2007. Assumimos a hipótese de que a transferência do PFL para a oposição a partir de 2003, fato inédito na história do partido e que foi decorrente da chegada do PT ao poder federal, foi o evento determinante para a decisão de seus dirigentes de tentar dar nova imagem e identidade ao PFL. Argumentamos também que a refundação teve como objetivo reposicionar o PFL no mercado político eleitoral brasileiro de modo a que pudesse atrair o apoio da classe média urbana localizada nas cidades de médio e grande porte. Mostramos que a passagem para a oposição desencadeou o enfraquecimento do PFL. Dois movimentos conjugados provocaram o retraimento do partido: 1) a transferência de políticos pefelistas para legendas aliadas ao governo Lula; 2) o mau desempenho eleitoral na região Nordeste, reduto tradicional do PFL em sua fase governista e que passou a ser progressivamente dominado por partidos que apoiavam a administração petista. Por fim, com base nos resultados das eleições municipais de 2000, 2004 e 2008, apresentamos dados e testes estatísticos que sustentam a ideia de que os municípios menos desenvolvidos, menos populosos, localizados no Nordeste e cujas economias são mais dependentes do setor público possuem viés governista. Isto é, nessas localidades, mais do que no restante do país, o poder local tende a se alinhar com o poder federal. Tal tendência parece fornecer uma boa explicação para o retraimento do PFL nos municípios com as características acima definidas.
This dissertation aims to analyze the re-foundation process of the Partido da Frente Liberal (PFL), which resulted in the change of command of the party and the replacement of the previous name of the legend by Democrats (DEM) in March 2007. We assume the hypothesis that the transfer of the PFL for the opposition since 2003, unprecedented in the history of the party and that was determined by the arrival of PT in the federal government, was the crucial event to the decision of party leaders to try to give new image and identity to the PFL. We argue also that the re-foundation aimed to reposition the PFL in Brazilian electoral political market in order to attract the support of the urban middle class located in large and medium-sized cities. We show that the transition to the opposition led to the weakening of the PFL. Two movements together caused the retreat of the party: 1) the transfer of PFL politicians to parties allied to Lula´s administration, 2) the poor electoral performance in the Northeast, traditional stronghold of the PFL during the time it was in the government and that was progressively dominated by parties which supported PT administration. Finally, dealing with the results of municipal elections in 2000, 2004 and 2008, we present data and statistical tests that support the idea that less developed municipalities, few populated, located in the Northeast region and whose economies are more dependent on public sector have a progovernment bias. That is, in these locations, more than in the rest of the country, local government tends to align with the federal government. This trend seems to provide a good explanation for the withdrawal of the PFL in municipalities with the characteristics specified above.

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30

Heller, Ondřej. "Akumulace energie z OZE." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218539.

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The objective of the first part of master’s thesis is mapping the potential of various types of renewable sources in Europe and Czech Republic, especially solar energy, wind energy, water energy and biomass. There are described principals and ways of energy generation from these sources, brief overview of current technologies, and also their advantages and limitations. An important part is electric supply continuity from renewable sources, there are large differences and the resulting to restrictions on construction and connecting the units to the power system. In this work there are mentioned some impacts on network and rates of change of supply, some sources are also evaluated in terms of maximum power, that can be connected to the power system in our country. The conclusion of the first part is dedicated to energy storage technologies, which are suitable and usable for renewable sources, there are described their principals, properties, status of development and types of aplications, in which these technologies are used. This chapter also focusses on the price level of each technology. The second part of the thesis deals with 1 MWp on-grid photovoltaic power plant design. This design includes also the redox flow batteries accumulation, the first variant calculates on 24-hour steady energy supply, the second optimalized variant calculates on daily energy supply. There are the accumulation system costs estimated and also the payback period for the both variants. Additionally there is also determined minimum penalization for cost-effective operation. The last part is dedicated to changes of impact on the local grid and changes of system impacts, after the accumulation system is installed.

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Junior, Irineu Francisco Barreto. "Poder local e política: a saúde como locus de embate na cidade de Santos - SP." Pontifícia Universidade Católica de São Paulo, 2005. http://tede2.pucsp.br/handle/handle/2741.

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Made available in DSpace on 2016-04-25T20:22:02Z (GMT). No. of bitstreams: 1 Irineu_final.pdf: 653995 bytes, checksum: 0bc875d153f5a6dd1c802b2c995fbc69 (MD5) Previous issue date: 2005-05-20
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This work has the principal task compares municipal public helth in the city of Santos, São Paulo, during Telma de Souza (1988-1992); David Capistrano (1993-1996) and Beto Mansur (1997-2004) administrations. Therefore, this investigation will not abide exclusively to local health systems. It was become fullfield a general analization about the presence and importance of health in publics politics developments, includes majors successions; participation os politicians actors to lead and taking decisions; such as integrant s of municipal health politics; and councilmen congress. Also surpassing public health beyond local importance, and institucional dimensional, intended to investigate the presence and importance about this subject in the politicians interests of the cited city, during the elections in 1988 and 2000
Este trabalho teve como objetivo principal realizar um estudo comparativo da política municipal de saúde na cidade de Santos, Estado de São Paulo, durante as administrações de Telma de Souza (1988-1992), David Capistrano (1993-1996) e Beto Mansur (1997-2004). Essa investigação, porém, não se subscreve unicamente ao sistema local de saúde: realizou-se uma análise sobre a presença e a importância da saúde na agenda política da cidade, incluindo o processo sucessório dos prefeitos e a participação dos atores políticos na condução e no processo de tomada de decisões. Extrapolando a questão da saúde para além de seus domínios mais imediatos e da dimensão institucional, pretendeu-se investigar a presença e a importância do tema no centro dos embates políticos travados no município, incluindo, dessa maneira, as eleições realizadas na cidade, entre 1988 e 2000

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32

Barreto, Junior Irineu Francisco. "Poder local e política: a saúde como locus de embate na cidade de Santos - SP." Pontifícia Universidade Católica de São Paulo, 2005. https://tede2.pucsp.br/handle/handle/3859.

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Made available in DSpace on 2016-04-26T14:56:47Z (GMT). No. of bitstreams: 1 Irineu_final.pdf: 653995 bytes, checksum: 0bc875d153f5a6dd1c802b2c995fbc69 (MD5) Previous issue date: 2005-05-20
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
This work has the principal task compares municipal public helth in the city of Santos, São Paulo, during Telma de Souza (1988-1992); David Capistrano (1993-1996) and Beto Mansur (1997-2004) administrations. Therefore, this investigation will not abide exclusively to local health systems. It was become fullfield a general analization about the presence and importance of health in publics politics developments, includes majors successions; participation os politicians actors to lead and taking decisions; such as integrant s of municipal health politics; and councilmen congress. Also surpassing public health beyond local importance, and institucional dimensional, intended to investigate the presence and importance about this subject in the politicians interests of the cited city, during the elections in 1988 and 2000
Este trabalho teve como objetivo principal realizar um estudo comparativo da política municipal de saúde na cidade de Santos, Estado de São Paulo, durante as administrações de Telma de Souza (1988-1992), David Capistrano (1993-1996) e Beto Mansur (1997-2004). Essa investigação, porém, não se subscreve unicamente ao sistema local de saúde: realizou-se uma análise sobre a presença e a importância da saúde na agenda política da cidade, incluindo o processo sucessório dos prefeitos e a participação dos atores políticos na condução e no processo de tomada de decisões. Extrapolando a questão da saúde para além de seus domínios mais imediatos e da dimensão institucional, pretendeu-se investigar a presença e a importância do tema no centro dos embates políticos travados no município, incluindo, dessa maneira, as eleições realizadas na cidade, entre 1988 e 2000

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33

Studýnka, Radim. "Modely a analýzy v kontejnmentovém systému s potlačením tlaku při haváriích s únikem chladiva." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231495.

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This diploma thesis deals with a pressure suppression system containment during the loss of coolant accidents. It is focused on the containment systems of the nuclear power plants with VVER-440/V-213 reactors. There is described the process of loss of coolant accident. There was designed input model which consists of the zones representing the areas which are connected with junctions and heat structures. Were then selected input parameters for the model calculations. And finally, there have been several calculations for the selected parameters.

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34

Lakva, Petr. "Výroba vodíku z obnovitelného zdroje elektrické energie." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230583.

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Hydrogen, as a form of storage for the excess energy from renewable sources, is a technically and economically viable option. However, the technology is not mature enough to compete with the other renewable energy possibilities. In this thesis, a study based on coupling two 330 kW wind-turbines with an NELP. 40 electrolyzer this connection should improve the utilization of wind power. In this thesis are two options of energy utilization. The energy produced by the wind-turbine is stored in the form, of hydrogen and is then delivered for consumption at variable power through a fuel cell, second option is use of produced hydrogen as alternative fuel for cars. This study is a general introduction for the wind energy system with hydrogen storage. Future studies should be more complex and detailed in order to understand and model the system with greater accuracy and to increase the possibility for the utilization of wind energy to generate hydrogen. This would enhance wind power competitiveness and sustain the continuously changing world energy demands.

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Flygare, Carl. "A market-based instrument for renewable energy : Modelling a dynamic price function for local areas." Thesis, Uppsala universitet, Institutionen för samhällsbyggnad och industriell teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-403002.

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This thesis describes the current situation of the electrical grid on a general level and contemporary support policies for residents who feed renewably produced electricity into the grid within a Swedish context. It shows which issues currently exists and suggests a new way to value overproduced renewable electricity which is not self-consumed. This way is called a dynamic price function (DPF), and this thesis models, simulates and analyzes the DPF in order to create an economic incentive to support the balance of the electrical grid – one of its most important parameters. The suggested DPF could potentially work with any renewable source in any area, but the focus in this thesis has been on solar power-systems for households in local areas. While the currently support policies, which uses static models to value overproduced renewable electricity, have created important incentives for the initial penetration of solar power among local residents they do not scale well as the share of renewable production on a local level increase. This might cause negative impacts on the electrical grid. The thesis’ results show that by designing the DPF in certain ways it is possible to create an economic incentive for different behaviors. The most promising design incorporates three different incentives at the same time and they are: 1) to incentivize the initial penetration of solar power in local areas which do not have any production, 2) to incentivize a higher share of solar power, but not too high, and 3) to procure storage possibilities for overproduced electricity. These incentives do not only encourage a more even geographical distribution of solar power, but also allow for a higher share of solar power in the energy system without risking the balance of the grid.

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36

Löfgren, Louise. "Elbilsladdnings påverkan på elnätet : Simuleringar av Gävles lokala elnät med olika laddningsmönster." Thesis, Högskolan i Gävle, Energisystem och byggnadsteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-36846.

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Transportsektorn står inför en omställning från förbränningsfordon till eldrivna fordon. Detta är en åtgärd för att minska koldioxidutsläppet inom transportsektorn och därmed reducera klimatpåverkan. Syftet med studien är att undersöka hur en ökad effektanvändning i form av elbilsladdning påverkar Gävles lokala elnät samt hur olika laddtekniker påverkar elnätet. Bakgrunden till studien grundar sig att elnätsföretaget vill öka medvetenheten om hur elnätets beredskap ser ut för en ökad elbilsladdning. Att undersöka elbilsladdningens påverkan på elnätet är av stor nytta för elnätsföretaget, men även andra som undersöker elbilsladdnings påverkan i elnätet kan ha användning för studien. Ämnet elbilsladdning är mycket aktuellt och många studier undersöker olika delar som berör elbilsladdning. Tidigare studier undersöker även olika typer av laddtekniker och hur smart laddning minska påverkan i elnätet. Smart laddning kan anpassa elbilsladdningen genom att styra den efter olika styrsignaler och sammankoppla hela elnätet. Denna studie undersöker delar av Gävles lokala elnät genom att simulera befintliga mätvärden lågspänningsnätet samt olika typer av elbilsladdning. Studien analyserar effektanvändningen av befintliga mätdata samt belastningsström och spänningsfall i elnätet med varierande lastprofiler i fyra olika områden. Resultatet för denna studie visar att elbilsladdning påverkar elnätet, vilket beror på vilken typ av laddteknik som används samt dimensioneringen av elnätet. Studien visar att elanvändningen i området idag har effekttoppar på eftermiddag och kväll när kunderna består av villakunder men att effekttoppen kan vara mitt på dagen där det finns industrier. Med elbilsladdning ökar belastningen samt spänningsfallet i nätet och en del av säkringarna i nätet löser ut. Laddning med 11 kW mellan kl. 16:00-19:00 samt laddning med effektvakt på 13,8 kW ger störst belastning och spänningsfall. Laddning utan styrning är den laddteknik som påverkar elnätet mest men laddning med effektvakt orsakar också problem. Laddning med 5,5 kW mellan kl. 23:00-06:00 samt när endast 50% av alla kunder laddar med 11 kW mellan kl. 16:00-19:00 är de scenarion som påverkar elnätet minst. Laddning med en låg effekt under natten när grundlasten är som lägst är den laddteknik som är mest gynnsam för elnätet. Studien visar även att nätet klarar en högre belastning av elbilsladdning inom en snar framtid om endast en del av kunderna i nätet använder elfordon.
The transport sector is facing a transition from combustion engine vehicles to electric vehicles. Through this action the carbon dioxide emissions in the transport sector can be reduced. The purpose of this study is to observe how an increased power use from electric vehicle charging (EVC) affects the local electricity grid in Gävle. The study also addresses how different charging techniques affect the electricity grid. The background of this study is to the increase awareness of the capacity of the electricity grid. There is a need from the electricity grid company to look over the impact on the grid from EVC. This could also be useful for others looking over the impact on the electricity grid from EVC. This is a hot topic and lots of other studies look over the different aspects of EVC. Previous studies also examine different types of charging techniques and how smart charging reduces the negative impact on the electricity grid. Smart charging is a way to adjust the EVC by regulating it after different parameters and connecting the entire electrical grid. This study simulates existing measured values of the low-voltage grid in Gävle and various types of EVC. This study examines the power use of existing measurement data as well as load current and voltage drops in the electricity grid with different load profiles in four different areas. Results from this study shot that EVC affects the electricity grid, to what extent depends on the type of charging technology used and the dimensions of the electricity grid. The study shows that electricity use in the area has power peaks in the afternoon and evening with residential customers, but power peaks tend to be in the middle of the day if there are industries in the area. EVC increase the load on the electricity grid, causes voltage drops and a few fuses in the grid to be triggered. Charging with 11 kW between 16:00-19:00 and charging with a power monitor of 13.8 kW create the greatest voltage drops and highest load on the grid. Charging without means of control affects the electricity grid the most but charging with a power monitor also creates problems. Charging with 5.5 kW between 23:00-06:00 as well as when only 50 % of all customers charge with 11 kW between 16:00-19:00 impacts the grid the least. Charging with low power during the night when the base load is at its lowest is the charging technology that is most favorable for the electricity grid. Results also show that the grid can handle a higher load of EVC in the near future if only some of the customers in the network start using electric vehicles.

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37

Kukla, Zdeněk. "Vzdálené měřicí systémy a jejich praktické využití." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217602.

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This master’s thesis is dealing with remote measuring systems and their utilization in power engineering. In the first part there are described requirements on an autonomous measuring system and description of AMM and AMR systems. Communicating and data flows working on accurately defined communicating layers are also depicted in this part. The attention is devoted to the possibility of data processing and functions of devices offered by these attributes. In the following part there are described reasons for utilization of remote measuring systems in power engineering and the main advantages of connection of more devices into one unit. After finding of required parametres and functions of systems, a suggestion of terminal device is created in the same way. The suggestion is described in the measuring part with A/D converter, processing in microprocessor, measuring and evaluating alogorithms and attributes of communication of bus used. The last part is devoted to utilization of remote analysis in small power stations in dispersed production. Formation of deformation of voltage, harmonic analysis of signal and its application for data processing are described there. Described analysis was tested on data acquired from a cogeneration unit.

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38

Su, Hui-Yuan, and 蘇暉淵. "Analysis of Power System Inter-Area and Local Electro-Mechanical Oscillation Mode." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/06145381088400332205.

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碩士
國立臺灣海洋大學
電機工程學系
95
Low frequency oscillations are likely to decrease power transfer capability and hence have influence on power system stability and security. It is a common practice to install the power system stabilizer on the generator for providing additional damping to alleviate the effect caused by low frequency oscillations. The main objective of this thesis is to study the dynamic stability problem, including analysis of dynamic characteristics and design of power system stabilizer, for a thermal plant during peak and off-peak periods. First, the dynamic model of the study system is established for performing dynamic analysis both in the frequency domain and the time domain. The frequency domain analysis is to calculate the eigenvalues and the corresponding eigenvectors of the study system for analyzing the oscillation mode shapes and dynamic characteristics between the generating units. The time domain analysis focuses on the computation and simulation of sysem transient responses to disturbances such as tripping of some generator, tripping of transmission lines, and faults on the generator bus. Moreover, the effects of installing the power system stabilizer both on the improvement of dynamic stability and on the dynamic characteristics of the power plant under study.

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39

van, Eyk Helen Clare. "Power, trust and collaboration a case study of unsuccessful organisational change in the South Australian health system /." 2005. http://catalogue.flinders.edu.au/local/adt/public/adt-SFU20060130.095828/index.html.

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Lin, Ching-Lung, and 林清隆. "Deployment of an Intelligent Dynamic Local Power Dispatch System Using LAN and Wireless Technology." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/22070934596475437456.

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博士
中原大學
電子工程研究所
94
Abstract Escalating energy costs and the overloaded power plants during peak demand periods are major concerns many industrialized nations have to deal with today. This dissertation discusses the deployment of an Intelligent Dynamic Local Area Power Dispatch System (IDLAPDS) utilizing Radio Frequency (RF) and local Area Network (LAN) technologies consis of Local Power Dispatch Card (LPDC), Local Host System (LHS) and Central Power Dispatch System (CPDS). In this paper, the authors will further discuss on ways to incorporate Artificial Intelligence (AI) ideologies in building a LAPDS that is both more efficient in energy deployment and saving. In this dissertation, the author consists of the idea of Artificial Intelligence and LAPDS to present the IDLAPDS, which links 'how to disperse power load' and 'how to economize the power effectively'. The main targets of the system is to reduce peak, to shorten sharp from peak load indirectly, to release power developing and power deman, and to dispatch and save the power more effectively. There are two application cases in this dissertation. An electronic factory that the factory reduced peak load by IDLAPDS for several months. It is not only to drop peak load 21.6%, to reduce sharp, but also to save more than NT$40,000 in September. That is very considerable result, which reduces electric rate by nearly 14% in a month. Another case, an university is made up by 8500 students and more than 600 lecturers and staffs. There are more than 100 air-conditioning classroom, which are controlled by IDLAPDS to pander to the experiment goal of this research. Author converts the lecturing timetables to the system control parameters. The devices are controlled by LPDCs, and LPDCs transfer the parameters to LHS by using RF to procure for the Intelligence power load dispatch. The system economizes nearly 10% electricity for one week.

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41

Zeng, Y., L. Zhang, J. Qian, and Yakun Guo. "Fifth order generator Hamiltonian model under local multi-machine condition of a power station." 2014. http://hdl.handle.net/10454/10824.

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No
Under local multi-machine condition, voltage and current changes of generator d and q axis are important parameters that mirror the coupling characteristics between local generator and others. Fifth order generator Hamiltonian model included electromagnetic transient of the d and q axis is established in this paper, which provides a foundation that reveals inner dynamics mechanism of multi-machine coupling and interaction. Based on electromechanical analysis dynamics theory, each of subsystem Lagrange function, dissipative function and generalized forces can be derived from fundamental energy relationship of the generator, then the Lagrange-Maxwell equations of the generator can be derived. The equations are transformed into the generalized Hamiltonian model by defining the generalized momentum, in which its structure is clear, its energy flow is consistent with actual physical system ones. The Hamiltonian model of generator is improved by the transition to that with practical parameters resulting from local simplified method. The conception of the local multi-machine system of power station is proposed, implicit multi-machine system Hamiltonian model described by measurable parameters on the generator port is derived. Analysis show that proposed model is well in structure.

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42

Nel, Coenraad Josephus. "Simulation and characterisation of a concentrated solar power plant / Coenraad Josephus Nel." Thesis, 2015. http://hdl.handle.net/10394/15471.

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Concentrated solar power (CSP) is an efficient means of renewable energy that makes use of solar radiation to produce electricity instead of making use of conventional fossil fuel techniques such as burning coal. The aim of this study is the simulation and characterisation of a CSP plant in order to gain a better understanding of the dominant plant dynamics. Due to the nature of the study, the dissertation is divided into two main parts namely the simulation of a CSP plant model and the characterisation of the plant model. Modelling the CSP plant takes the form of developing an accurate Flownex® model of a 40 MW combined cycle CSP plant. The model includes thermal energy storage as well as making use of a duct burner. The Flownex® model is based on an existing TRNSYS model of the same plant. The Flownex® model is verified and validated, by making use of a bottom-up approach, to ensure that the developed model is in fact correct. The characterisation part of this dissertation involves evaluating the dynamic responses unique to that of a CSP plant as stated in the literature. This involves evaluating the dominant dynamic behaviour, the presence of resonant and anti-resonant modes found within the control bandwidth, and the change in the dynamics of the plant as the plants’ operating points change throughout the day. Once the developed model is validated, characterisation in the form of evaluating the open loop local linear models of the plant is implemented. In order to do so, these models are developed based on model identification processes, which include the use of system identification software such as Matlab® SID Toolbox®. The dominant dynamic behaviour of the plant model, obtained from the developed local linear models, represents that of an over damped second order system that changes as the operating points of the plant change; with the models’ time responses and the bandwidth decreasing and increasing respectively as the thermal energy inputs to the plant increases. The frequency response of the developed local linear models also illustrates the presence of resonant and antiresonant modes found within the control bandwidth of the solar collector field’s temperature response. These modes however are not found to be present in the mechanical power output response of the plant. The use of adaptive control, such as feedforward and gain-scheduled controllers, for the plant should be developed to compensate for the dynamic behaviours associated with that of a CSP plant.
MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2015

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43

"The tariff system of a local electric power utility: its contribution to the company's performance in a changing environment." Chinese University of Hong Kong, 1991. http://library.cuhk.edu.hk/record=b5886671.

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by Mak Chai-ming.
Thesis (M.B.A.)--Chinese University of Hong Kong, 1991.
Bibliography: leaves 58-59.
ABSTRACT --- p.ii
TABLE OF CONTENTS --- p.iii
LIST OF ILLUSTRATIONS --- p.v
ACKNOWLEDGEMENT --- p.vi
Chapter
Chapter I --- INTRODUCTION --- p.1
Chapter II. --- THE POWER INDUSTRY AND ITS PRODUCT --- p.3
The Characteristics of Electricity --- p.3
Power Industry of Hong Kong --- p.4
The Product Profile of Electricity --- p.5
Load Factor --- p.6
Load Factor and Cost --- p.7
Chapter III. --- BUSINESS CHALLENGES IN THE POST WAR DECADES --- p.12
The Critical Problems - The First Challenge --- p.13
The Scheme of Control Agreement --- p.14
Goals and Objectives of CLP --- p.15
Coal as Input - The Second Challenge --- p.16
Chapter IV. --- COST OF ELECTRICITY AND ITS PRICING --- p.18
The Tariff Structures --- p.18
The Tariff of the Past --- p.19
The Present Tariff --- p.19
Cost of Service Study Model --- p.20
Cost Identification --- p.21
Cost Functionalisation --- p.21
Costing Period Determination --- p.22
Cost Allocation --- p.27
Results and Interpretation --- p.28
Rate of Return Determination --- p.28
Unit Cost Analysis --- p.31
Chapter V. --- REVIEW OF THE PRESENT TARIFF STRUCTURE --- p.35
Objectives of the Present Tariff --- p.35
Performance of the Tariff --- p.36
Performance of the Company --- p.37
Load Factor Improvement --- p.40
Chapter VI --- THE NEW CHALLENGES AND THE STRATEGIES --- p.42
The New Challenges --- p.42
Changes in The External Market --- p.42
The 1997 Issue of Hong Kong --- p.43
Fuel Advantages Exhausted --- p.44
The Company's Strategies Facing the New Challenges --- p.44
Deferring Capital Investment --- p.45
Supply Side Management --- p.45
Diversification --- p.46
Chapter VII. --- PROJECTED PERFORMANCE OF THE TARIFF --- p.49
Maximum Demand Forecast and Generating Capacity Requirement --- p.49
Projected Expenditure and Revenue Requirement --- p.50
The New Objectives of the Tariff --- p.50
Least Cost Planning --- p.50
Energy Conservation --- p.50
Factors to Consider for the Detailed Design of the Tariff --- p.50
Price Elasticity --- p.52
Scheme of Control --- p.52
Load Factor Improvement --- p.52
Chapter VIII. --- CONCLUSION --- p.53
APPENDIX --- p.54
BIBLIOGRAPHY --- p.58

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"Exploration of a Scalable Holomorphic Embedding Method Formulation for Power System Analysis Applications." Doctoral diss., 2017. http://hdl.handle.net/2286/R.I.45022.

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abstract: The holomorphic embedding method (HEM) applied to the power-flow problem (HEPF) has been used in the past to obtain the voltages and flows for power systems. The incentives for using this method over the traditional Newton-Raphson based nu-merical methods lie in the claim that the method is theoretically guaranteed to converge to the operable solution, if one exists. In this report, HEPF will be used for two power system analysis purposes: a. Estimating the saddle-node bifurcation point (SNBP) of a system b. Developing reduced-order network equivalents for distribution systems. Typically, the continuation power flow (CPF) is used to estimate the SNBP of a system, which involves solving multiple power-flow problems. One of the advantages of HEPF is that the solution is obtained as an analytical expression of the embedding parameter, and using this property, three of the proposed HEPF-based methods can es-timate the SNBP of a given power system without solving multiple power-flow prob-lems (if generator VAr limits are ignored). If VAr limits are considered, the mathemat-ical representation of the power-flow problem changes and thus an iterative process would have to be performed in order to estimate the SNBP of the system. This would typically still require fewer power-flow problems to be solved than CPF in order to estimate the SNBP. Another proposed application is to develop reduced order network equivalents for radial distribution networks that retain the nonlinearities of the eliminated portion of the network and hence remain more accurate than traditional Ward-type reductions (which linearize about the given operating point) when the operating condition changes. Different ways of accelerating the convergence of the power series obtained as a part of HEPF, are explored and it is shown that the eta method is the most efficient of all methods tested. The local-measurement-based methods of estimating the SNBP are studied. Non-linear Thévenin-like networks as well as multi-bus networks are built using model data to estimate the SNBP and it is shown that the structure of these networks can be made arbitrary by appropriately modifying the nonlinear current injections, which can sim-plify the process of building such networks from measurements.
Dissertation/Thesis
Doctoral Dissertation Electrical Engineering 2017

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Balog, Robert S. "Autonomous local control in distributed DC power systems /." 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3223540.

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Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006.
Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3981. Adviser: Philip T. Krein. Includes bibliographical references (leaves 130-142) Available on microfilm from Pro Quest Information and Learning.

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Kuzwayo, Mandlesizwe. "Local contect requirements and the manufacture of solar photovoltaic components in South Africa." Thesis, 2018. https://hdl.handle.net/10539/26284.

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Research report submitted to the faculty of Commerce, Law and Management, University of Witwatersrand, in 50% fulfilment of the requirements for the degree of Master of Management in the field of Public and Development Management. March 2018
The outputs in this report are based on the experiences, beliefs and perceptions of a crosssection of Solar Photovoltaic industry stakeholders on whether Local Content Requirements is an appropriate policy instrument for building a local industry and the extent to which the Local Content Requirements of the Renewable Energy Independent Power Producer Procurement Programme have led to an increase in the South African solar component manufacturing capacity since the programme’s inception in November 2011. Protectionist policies, including Local Content Requirements, were used by now industrialised countries to develop their respective countries, and continue to be used to this day despite World Trade Organisation prohibitions. Four models on building local industries are discussed and their relationship to the two research questions explored. Interview participants agreed that the Renewable Energy Independent Power Producer Procurement Programme was instrumental in building a large-scale local renewable energy industry in the country, created jobs and excitement around manufacturing capacity potential. However, many believe that programme design and implementation interventions are required to improve the programme’s localisation impacts. The latest draft Integrated Resource Plan’s sizeable allocation for Solar Photovoltaic until 2030 presents an opportunity to drastically improve localisation benefits for the country.
GR2019

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Trivette, Shawn Alan. "Farm-to-Fork: Understanding Locally-Oriented Farm-to-Vendor Food Systems: Access, Boundaries, and Power-Relations." 2012. https://scholarworks.umass.edu/open_access_dissertations/670.

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Locally oriented food has recently gained considerable popularity as an alternative to the industrial food system. Current scholarship on local food has typically focused on direct-to-consumer (DTC) arrangements, such as farmers' markets or CSAs. Yet other players besides producers and consumers engage with locally-oriented food. Food vendors (restaurants, retailers and grocers, and value-added food processors) have recently entered the scene and locally-oriented farm-to-vendor arrangements constitute one of the cutting edges of the development of local food systems. This dissertation studies one such local food system in southern New England. Utilizing a mixed methods approach entailing social network analysis, in-depth interviews, fieldwork observations, and GIS analysis, this study interrogates how direct-to-vendor (DTV) local food systems operate. I show through the literature review that though local food systems hold considerable promise, they are not inherent mechanisms of sustainability. Next I turn to the question of what "counts" as local, examining the range of distances farms and vendors within this region travel to sell or purchase food, and asking what are the forces and conditions that influence this range of travel? The greatest influences are number of ties to other local food entities, what type of farm or food-vendor they are, size, and urban proximity. I then focus on key participants in the area of study. What are the challenges and constraints around developing a vibrant locally-based food system? These participants face continual pressure to expand their size and markets, emulating the dominant food system and thereby undercutting their sustainable potential. However, these participants also find ways to overcome what are sometimes contradictory interests to forge a functional locally-based food system based on reciprocity and trust. Due in part to price premiums on local food many local food participants tend to be white and have high incomes and levels of education. In the final empirical chapter I ask: in what ways do these inequalities manifest systematically? By geospatially mapping the locations of local food outlets against census data on race, income, and education, I show that racial and class advantages are perpetuated in terms of people's proximal access to these local food outlets.

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Pereira, Flávio Adriano Alves Duarte. "A Contratualização do Estado (delegado no poder local) com o Terceiro Setor." Master's thesis, 2018. http://hdl.handle.net/10316/85828.

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Dissertação de Mestrado em Administração Público-Privada apresentada à Faculdade de Direito
RESUMOO presente estudo tem como finalidade apresentar uma reflexão em primeiro plano uma abordagem ao mundo do setor da solidariedade social que constitui o Terceiro Setor, quer no espaço nacional, quer no espaço da união europeia.Em seguida abordamos a importância da “descentralização do poder” com base nos contratos interadministrativos provenientes do mecanismo da “delegação de competências” do Estado para os Municípios, para que estes possam negociar com mais autonomia com o Terceiro Setor, em prol de uma maior proximidade com os cidadãos locais.Por sua vez, e para concluir é apresentado um modo de fiscalização por intermédio de uma Autoridade Administrativa Independente, para que, os efeitos dos contratos realizados entre Estado e Terceiro Setor, sejam efetivamente realizados.RESUMOO presente estudo tem como finalidade apresentar uma reflexão em primeiro plano uma abordagem ao mundo do setor da solidariedade social que constitui o Terceiro Setor, quer no espaço nacional, quer no espaço da união europeia.Em seguida abordamos a importância da “descentralização do poder” com base nos contratos interadministrativos provenientes do mecanismo da “delegação de competências” do Estado para os Municípios, para que estes possam negociar com mais autonomia com o Terceiro Setor, em prol de uma maior proximidade com os cidadãos locais.Por sua vez, e para concluir é apresentado um modo de fiscalização por intermédio de uma Autoridade Administrativa Independente, para que, os efeitos dos contratos realizados entre Estado e Terceiro Setor, sejam efetivamente realizados.
ABSTRACTThe purpose of the present study is to present a reflection in the forefront of an approach to the world of the social solidarity sector that constitute the Third System, both in the national space and in the space of the European Union.Next, we address the importance of “decentralization of power” based on the inter-administrative contracts from the mechanism of “delegation of powers” of the State to the Municipalities, so that they can negotiate with more autonomy with the Third System, in order to be closer to the citizens.In turn, and in order to conclude, a form of supervision is presented through an “Independent Administrative Authority”, so that the effects of the contracts executed between State and Third System, are effectively realized.ABSTRACTThe purpose of the present study is to present a reflection in the forefront of an approach to the world of the social solidarity sector that constitute the Third System, both in the national space and in the space of the European Union.Next, we address the importance of “decentralization of power” based on the inter-administrative contracts from the mechanism of “delegation of powers” of the State to the Municipalities, so that they can negotiate with more autonomy with the Third System, in order to be closer to the citizens.In turn, and in order to conclude, a form of supervision is presented through an “Independent Administrative Authority”, so that the effects of the contracts executed between State and Third System, are effectively realized.

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Buchan, Robert Bruce. "Transformative incrementalism: a grounded theory for planning for transformative change in local food systems." Thesis, 2017. https://dspace.library.uvic.ca//handle/1828/8989.

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Local Food Systems (LFS) is a relatively new concept in geographical and planning research. Academic, professional, and public interest in LFS is in part a reaction against the social, environmental, and economic effects of a dominant Production Agriculture paradigm (Lyson, 2004), and growing concern with the potential impacts of climate change on the food supply (Ostry, Miewald, and Beveridge, 2011). While there is a growing public and policy interest in making transformative change in LFS, there is a lack of theoretical work that addresses how change processes in food systems occur. In this study, a classic Glaserian grounded theory research project investigated the subject area of local food system planning. The primary research goal was the development of a theory grounded in the experience of practitioners, elected officials, and members of the public. The emergent theory, called Transformative Incrementalism (TI) describes the social process underlying planning initiatives focused on achieving significant (transformative) change in local food systems. The data for this research project are drawn from interviews with 29 elected officials, public stakeholders, and planning staff in five communities with local food system initiatives. In addition, 10 member checking interviews were also conducted. The core category identified in the emergent TI theory was Power, with Values, Praxis, and Outcomes being other main themes. From this research, Power could be defined as the ability, through authoritative and non-authoritative influence, to have an effect on a person, process, action, or outcome. Values act as sources of power to the extent that they motivate and drive the actions of individuals and groups. Praxis includes activities designed to create, use, and maintain power, such as building relationships with other people that will give ongoing support for food planning initiatives. Outcomes include broader system and social changes resulting from local food system planning processes and activities. The main findings from this dissertation underscore the fact that the role of power has been largely ignored in the planning literature (Friedman, 2011; Flyvbjerg, 2012; Assche, Duineveld, and Buenen, 2014). Power is the main driver of change; therefore, a lack of understanding about what power is and how it operates would seem to compromise the ability of planning efforts to be effective. This research identifies and illustrates the interrelationship between the political, public, and bureaucratic spheres of actors, and examines how values, praxis, and outcomes are pivotal to transformative change in food planning initiatives. Transformative change is achieved through a long process of incremental efforts (programs, policies, and actions) by actors within the public, political, and bureaucratic groups whose values and beliefs converge and align over time. The incremental efforts are intended to support a transformative change goal.
Graduate

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Jen-Yu, Pan, and 班仁瑜. "The Comparison on Autonomous Powers between Province-County Autonomous Law and Local System Law in Taiwan." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/57170771335419588596.

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碩士
臺北市立師範學院
社會科教育研究所
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Abstract With Taiwan’s gradual democratization, the government has been accorded with more important public role with the civil society demanding higher quality policies and public services from the government. The local governments have to take new steps to meet people’s demands amid the change of the overall environment and institutional reforms. As far as hsiang (township, city) are concerned, the institutionalization of local system relaxes the restrictions on local governments. However, if the traditional bureaucratic red tape cannot be cut through, then serious gaps will arise between the government’s production capacities and people’s expectations. This research is intended to discuss and compare the autonomy accorded by the Province-County Autonomous Law and the Local System Law respectively as well as the essential subject matters of the design of the fundamental mechanisms of the Local System Law. In addition to literature analysis method and system research method, interviews were also conducted for the purpose of compiling data in view of interpreting the interviewees in clearer manner from the micro perspective and perceiving the issue on a macro platform. This research intends to discuss the operations of autonomy by hsiang (township, city) offices under the frameworks of the Province-County Autonomous Law and the Local System Law, and to provide recommendations for the future development directions for hsiang (township, city) offices. This research starts from the concept of autonomy and undertakes discussions on the current legal system design of local autonomy and the legal system and practical applications of hsiang (township, city) autonomy as well as the effects of the autonomous status of hsiang (township, city) to their development. Priority should be accorded to the initial design of hsiang (township, city) autonomy and the essence of local autonomy before determining whether township (township, city) autonomy should be abolished or the current hsiang (township, city) status should be retained. In addition, the introduction of relevant overseas and domestic institutions and supporting systems is necessary for serving as references for the future development of hsiang (township, city) and for the gradual adoption of a sound local system. Therefore, the objective of this research is to clarify the positioning of township (township, city) autonomy and the legal system design thereof. Attention is also drawn to the discussions of the legal system and practical applications of the autonomous and legislative power of hsiang (township, city) in view of enhancing institutional reforms and practical applications of hsiang (township, city) in the future and seeking solutions to disputes arising from hsiang (township, city) autonomous status.

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Dissertations / Theses on the topic 'Local power system'

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