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Rule, James Arthur. "A strategy for modeling hydroelectric plants and improving their performance." Diss., This resource online, 1988. http://scholar.lib.vt.edu/theses/available/etd-07282008-135937/.
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Gencoglu, Cihangir. "Assessment Of The Effect Of Hydroelectric Power Plants'." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612165/index.pdf.
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The Turkish TSO (TEIAS) has been leading a project that aims the synchronous interconnected operation of the Turkish Power System and the ENTSO-E CESA (former UCTE) System. For this purpose, this study concentrates on the specific problems related to the electromechanical systems of large size hydroelectric power plants regarding low frequency inter area oscillations, which are prone to occur once the interconnected operation is established. The expected frequency of inter area oscillations after interconnected operation is close to 0.15 Hz, which is in the frequency range of the speed governing structures of turbines, as explained in the first two sections of the thesis. In the third section, the nonlinear turbine governor model used throughout the study is explained. In the following part, the governor parameter tuning study with regard to the defined performance objectives is explained. Afterwards, the effect of the retuned governor settings of the sample hydroelectric power plants on a simple multi machine power system is shown. Following that, the system wide effect of removing the sources of negative damping, which are strongly dependent on the governor settings of the major hydroelectric power plants of the Turkish Power System, is shown. In the final part, conclusions are made on the operation of the hydroelectric power plants regarding the frequency stability of the system after synchronous interconnected operation of the Turkish Power System and the ENTSO-E CESA System.
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Wells, Philippa Katherine. "Uncovering "regimes of truth" locating and defining discourses associated with hydro-electric development in New Zealand : a thesis submitted to Auckland University of Technology in partial fulfilment of the Doctor of Philosophy, 2004." Full thesis. Abstract, 2004.
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Lemos, Hermann Friedenberg de 1958. "Estudos de repotenciação de usinas hidrelétricas por meio da motorização de poços vazios existentes." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265893.
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Orientador: Sérgio Valdir BajayDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: Este trabalho analisa a viabilidade técnica e econômica da motorização de poços vazios previamente escavados e concretados, existentes em dez usinas hidrelétricas brasileiras de médio e grande porte. O objetivo é acrescentar potência instalada e disponibilizar energia nova para atendimento ao horário de ponta de carga do Sistema Interligado Nacional (SIN). Foram coletados junto ao Centro Nacional de Operação do Sistema Elétrico (CNOS), dados operacionais hidroenergéticos consolidados ao longo de dez anos, referentes às vazões turbinada e vertida, produtividade, potência média produzida e potência média vertida. Os dados operacionais foram utilizados nas equações criadas para dimensionar a quantidade de poços a motorizar e os respectivos acréscimos de potência. Simulações sistêmicas foram realizadas junto ao Centro de Pesquisas de Energia Elétrica (CEPEL), para estimar os ganhos de energia provenientes dos acréscimos de potência, utilizando os modelos de simulação daquele Centro. Fluxos de caixa, compostos pelas despesas necessárias ao investimento e pelas receitas da venda da nova energia, proporcionaram a análise da viabilidade econômica. Os resultados encontrados mostram que somente a remuneração do ganho de energia resultante da motorização adicional não viabiliza economicamente a instalação de unidades geradoras na maioria dos poços vazios disponíveis nas usinas hidrelétricas analisadas. As principais conclusões sinalizam para a obtenção de soluções econômica e regulatória que fomentem a viabilização da motorização dos poços vazios sob a ótica do mercado comercializador de energia elétrica, incluindo a valoração do acréscimo de potência instalada
Abstract: This work examines the technical and economic feasibility of inserting power generation sets in empty pits previously excavated and concreted in ten medium and large Brazilian hydroelectric power plants. The goal is to add new installed capacity and energy available to meet the peak hour load of the National Interconnected System. Hydropower operational data consolidated over ten years, related to the generation and no generation flows, productivity, average power produced and poured average power, were collected from the National Center Operation of Electrical System. The operational data were used in equations created to scale the number of pits to be motorized and its power increases. Systemic simulations were performed by the Center for Electric Power Research to estimate the energy gains arising from increased power, using simulation models that Center. Cash flows with investment expenditures and revenues from the sale of new energy provided the analysis of the economic viability. The results show that only the compensation of the energy gain resulting from the additional motorization not economically feasible to install generating units in most empty pits available in hydro plants analyzed. The main conclusions point to the attainment of economic and regulatory solutions that foster the viability of empty pits¿ motorization from the perspective of wholesale electricity market, including the remuneration of the new installed capacity
Mestrado
Planejamento de Sistemas Energeticos
Mestre em Planejamento de Sistemas Energéticos
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Binus, Joshua D. "Bonneville Power Administration and the Creation of the Pacific Intertie, 1958 -1964." PDXScholar, 2008. https://pdxscholar.library.pdx.edu/open_access_etds/1724.
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Construction of the Pacific Northwest-Pacific Southwest Intertie (also known as the Pacific Intertie) began in 1964, following the culmination of a series of interrelated negotiations which included: 1) the planning for the construction and operation of the Pacific Intertie; 2) the passage of federal legislation that put limits on the export of electricity from the regions where it was generated; and 3) the full ratification of the Columbia River Treaty between the United States and Canada. By 1970, with construction complete, the Pacific Intertie allowed for the movement of more than 4,000,000 kilowatts of power among the electrical systems of British Columbia and eleven Western states, including 243 rural electrical cooperatives, municipal systems, and other public agencies. It had essentially become the backbone of the largest electrical grid in the Western world. In addition to widening the marketing area available to power producers throughout the grid, the Pacific Intertie also integrated the operations of the nation's largest hydropower system (Bonneville Power Administration), the largest privately owned electrical system (Pacific Gas & Electric), and the largest municipal power system (L.A. Department of Water and Power) in the country.
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Bertoncello, Ricardo. "Sistema de conexão de mini e micro centrais hidrelétricas às redes monofásicas das concessionárias." Universidade Tecnológica Federal do Paraná, 2011. http://repositorio.utfpr.edu.br/jspui/handle/1/335.
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Este trabalho tem por objetivo desenvolver um sistema de conexão entre unidades de geração trifásica e uma rede de distribuição de energia elétrica rural monofásica. O sistema proposto baseia-se em um conversor CA/CA. Este conversor é composto por um retificador trifásico modulado por largura de pulso e um inversor monofásico. O controle do sistema é realizado através de um controlador digital de sinais (DSC). Atualmente o custo para conexão de mini e micro centrais hidrelétricas às redes de distribuição das concessionárias é bastante elevado, principalmente pelo custo de implantação das redes de distribuição trifásicas, e isso gera impacto principalmente nos pequenos empreendimentos. Para os empreendimentos maiores, este custo é diluído no custo total da obra, não impactando de forma significativa na viabilidade do negócio. Este trabalho visa desenvolver um sistema de conexão que atenda os requisitos técnicos e as exigências legais e que ao mesmo tempo consiga reduzir os custos para a conexão de pequenos agentes geradores no sistema elétrico nacional, em localidades onde somente a rede monofásica esteja disponível. Com isso, pretende-se viabilizar economicamente a inserção de pequenos produtores no cenário de geração e comercialização de energia elétrica.The objective of this work is to develop a connection system between three-phase generation units and a single phase rural distribution electricity network. The proposed system is based on an AC/AC converter. This converter consists in a threephase PWM rectifier and a single-phase PWM inverter. System control is performed by a Digital Signal Controller (DSC). Currently, the cost for connecting mini and micro hydropower plants to distribution networks of utilities is very high, especially because of the three phase distribution networks deployment cost, which generates impact mainly in small businesses. For larger businesses, this cost is diluted within the total work costs, not significantly impacting business viability though. This work aims at developing a system that meets the technical and legal connection requirements and, at the same time, will be capable of reducing costs for connecting small generating agents in the national power system in locations where only a single-phase network is available. Therefore, we intend to make economically viable insertion of small producers in the generation and sale electricity scenario.
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Sun, Haibin. "Integrated Modeling of Electric Power System Operations and Electricity Market Risks with Applications." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14103.
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Through integrated modeling of power system operations and market risks, this thesis addresses a variety of important issues on market signals modeling, generation capacity scheduling, and electricity forward trading. The first part of the thesis addresses a central problem of transmission investment which is to model market signals for transmission adequacy. The proposed system simulation framework, combined with the stochastic price model, provides a powerful tool for capturing the characteristics of market prices dynamics and evaluating transmission investment. We advocate the use of an AC power flow formulations instead since it allocates transmission losses correctly and reveals the economic incentives of voltage requirements. By incorporating reliability constraints in the market dispatch, the resulting market prices yield incentives for market participants to invest in additional transmission capacity. The second part of the thesis presents a co-optimization modeling framework that incorporates market participation and market price uncertainties into the capacity allocation decision-making problem through a stochastic programming formulation. Optimal scenario-dependent generation scheduling strategies are obtained. The third part of the thesis is devoted to analyzing the risk premium present in the electricity day-ahead forward price over the real-time spot price. This study establishes a quantitative model for incorporating transmission congestion into the analysis of electricity day-ahead forward risk premium. Evidences from empirical studies confirm the significant statistical relationship between the day-ahead forward risk premium and the shadow price premiums on transmission flowgates.
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Carvalho, Silvia Maria Simões de. "Metodos de pontos interiores aplicados ao problema de pre-despacho de um sistema hidroeletrico com manobras programadas." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/306750.
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Orientador: Aurelio Ribeiro Leite de OliveiraDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Resumo: Neste trabalho os métodos de pontos interiores primal-dual são utilizados para minimizar os custos e perdas na geração e transmissão do pré-despacho de fluxo de potência com corrente contínua (DC) em um sistema hidroelétrico com manobras previamente programadas. É realizado também o estudo da estrutura matricial desse problema e a alteração que ela impõe ao sistema. Uma função desenvolvida em Matlab que controla as manobras é exibida, e é adaptada na implementação de pontos interiores que não considera manobras, previamente desenvolvida. É realizada uma discussão sobre sua eficiência e algumas melhorias são propostas. É importante salientar que do ponto de vista computacional, o esforço por iteração para se resolver um problema com e sem manobras é semelhante, os motivos pelos quais isso ocorre também serão discutido nesse trabalho. Resultados computacionais com sistemas testes da IEEE e sistemas reais brasileiros comprovam esta afirmação
Abstract: In this work, the prima-dual interior point methods are used to minimize the DC predispatch generation and transmission costs on hydroeletric systems with previously scheduled maneuver. A study of the matrix structure is also performed considering the changes that occurs in the system after maneuvering. A function, developed in Matlab that controls the maneuver is shown and is adapted in the implementation of interior point methods already developed for the problem without maneuvers. It is important to stress that the computational effort to solve a problem with maneuver is close to the effort for solving the problem without it, the reason for it will be discussed ih this work. Computer results with test systems of the IEEE and real Brazilian systems reinforce this statement
Mestrado
Matematica Aplicada
Mestre em Matemática Aplicada
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Gomes, Leandro Costa Ferreira 1986. "Estudo da conexão da usina de Belo Monte ao SIN através da alternativa de transmissão em meia onda." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259505.
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Orientador: Luiz Carlos Pereira da SilvaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
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Resumo: O presente trabalho está inserido num contexto de busca de novas fontes de energia elétrica e de aproveitamento de grandes potenciais energéticos localizados distantes dos principais centros de carga. Para estes, alternativas não convencionais de transmissão também são exigidas, nas quais se insere a transmissão em linhas de pouco mais de meio comprimento de onda, distância de pouco mais de 2500km no sistema brasileiro à 60Hz. Como este tipo de transmissão nunca foi implementado, trata-se de uma proposta inovadora, pouco explorada e que exige ensaios elementares para testar-se a viabilidade, vantagens e desvantagens frente a outras alternativas de transmissão de energia elétrica. Esta dissertação visa investigar alguns aspectos referentes à tal método de transmissão de grandes montantes de potência em distintos cenários de interligação entre as regiões Norte e Sudeste do Brasil do SIN (sistema interligado nacional). Três distintos corredores compostos por linhas de pouco mais de meio comprimento de onda foram ensaiados. Inseridos conectando a usina de Belo Monte no Pará a Assis-SP na rede de 500kV, percorrendo 2664 km. Cada um dos corredores é composto por: três linhas de 800 kV e 4846 MW de potência característica (SIL); um segundo com duas das mesmas linhas de 800kV e um terceiro com duas linhas de 1000 kV e 8100 MW de potência característica. Cada aspecto é ensaiado em seis diferentes situações de carregamento do SIN e de fluxo de potência pelo corredor, abrangendo cenários de alto, médio e baixo carregamento das linhas assim como mudanças no sentido do fluxo entre Norte e Sudeste. Dentre os aspectos abordados estão: a avaliação e redução das perdas manipulando a potência característica operacional das linhas; o controle do carregamento do corredor através do uso de transformadores defasadores não convencionais; a inserção de cargas e geração em pontos intermediários deste e o controle do fluxo de potência reativa. Por fim, o estudo não aborda aspectos transitórios e é realizado com o auxílio do ANAREDE, software elaborado pelo CEPEL
Abstract: This work is placed in a search for new sources of power and exploitation of large energy potential located far from major load centers. For the second scenarios, alternate non-conventional transmission are also required, in which half wavelength transmission lines are inserted, resulting in a distance of just over 2500km for the 60Hz brazilian electrical system. Since this type of transmission has never been implemented, it is an innovative solution and few explored, requiring elementary studies to test the feasibility, advantages and disadvantages compared to other alternatives for bulk electric power transmission. This thesis aims to investigate some aspects related to such transmission method for large amounts of power into distinct scenarios of interconnection between the North and Southeast of Brazil's SIN (Brazilian National grid). Corridors consisting of three distinct lines of just over half wavelength were tested. Inserted connecting Belo Monte hydro power plant in Para to Assis in São Paulo through the 500kV network, covering 2664 km, each corridor is composed: by three lines of 800 kV and 4846 MW of Surge Load Impedance (SIL), the second one by two of the same 800kV lines and a third by two lines of 1000 kV and 8100 MW SIL. Each aspect is tested in six different SIN load situations and power flowing through the corridor, covering scenarios of high, medium and low lines loading as well as changes in flow direction between North and Southeast. Among the issues tackled are: evaluation and reduction of losses by manipulating operating lines SIL; line load controlling using non-conventional phase shift transformers; inserting loads and generation at intermediate points of the lines and control of reactive power flow. Finally, the study does not handle with transient aspects and is accomplished with the aid of ANAREDE, software developed by CEPEL
Mestrado
Energia Eletrica
Mestre em Engenharia Elétrica
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Souza, Patrícia Aparecida Pereira. "A privatização e descentralização do setor elétrico nacional frente à política ambiental brasileira: uma abordagem sociológica do caso das Pequenas Centrais Hidrelétricas (PCHs)." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-23082016-140628/.
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A onda de recessão econômica e de desaceleração do crescimento da década de 80, aliada à crise política e financeira vivenciada pelos Estados Nacionais na A.L., abriu terreno para que concepções neoliberais permeassem as decisões ligadas aos investimentos necessários em infra-estrutura. O Brasil, do Governo Collor ao FHC (1990 à 2002), seguiu esta orientação e, por meio dela, permitiu que vários segmentos dos serviços essenciais se tornassem passíveis de privatização e descentralização, dentre eles, o setor elétrico que foi reestruturado. Dado o contexto supra, este estudo visa analisar, sob um prisma sociológico e da geografia humana, o ressurgimento das pequenas centrais hidrelétricas no cenário nacional, intentando dar pistas da efetividade da política ambiental brasileira quando da implantação e recuperação destas usinas. Trata-se de examinar quais mecanismos político-institucionais permitem que o bem público, representado pelos recursos hídricos, possa ser apropriado para responder às necessidades de natureza privada, e como as necessidades sócio-ambientais imbricadas são contempladas nesse processo. É apresentado um estudo de caso para trazer à tona, por um micro recorte, a implantação de pequenos aproveitamentos hidrelétricos no qual a necessidade expansionista do setor reitera um padrão de excludência social e pouca efetividade decisória dos agentes sociais afetados.The 80\'s wave of economic recession and decelerated development, allied to political and financial crises experienced by Latin American National States, opened field to a spread-out of classic conceptions through decisions connected to necessary infra-structure investments. Brazil followed this orientation, from Collor to FHC (1990 to 2002), and allowed many essential service segments to become liable of privatization and decentralization, among them, the electric sector, which was re-structured. Considering this context, this study aims to analyze under sociological and human geographical viewpoints, the resurgence of Small Hydroelectric Power Plants on the national scenery, intending to give cues of the Brazilian environmental policy effectiveness, by the time of these plants implantation and recovery. It concerns of examining which are the political-institutional mechanisms that allow the public welfare, represented by hydrous resources, to be convenient to private nature demands, and how the involved social-environmental demands are analyzed on this process. A case study is presented in order to bring-up, through a short brief, the implantation of small hydroelectric plants, where the growing necessity of the sector, reaffirms a pattern of social exclusion and few conclusive effectiveness of the affected social agents.
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Lombard, Adriaan Cornelius Johannes. "Design and implementation of a low cost grid-connected 10 kw hydro power system." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4295.
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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: The world is increasingly being faced with the challenge of effectively exploiting available renewable energy resources, not only to meet an ever growing energy demand, but also to preserve the available amount of fossil fuels and to reduce the amount of carbon dioxide emissions released into the atmosphere by fossil fuelled power stations. Hence, every available renewable energy resource, even small rivers has a contribution to make in the attempt to reduce the amount of fossil fuel generated electricity. The focus of this study is the design and installation of a low cost grid-connected 10 kW micro hydro power system (MHPS). The process to determine the potential of the available water resource is first to be presented. The environmental aspects of these systems, based on the study that is undertaken for the implementation of the landmark example, are discussed. The complete design of a micro hydro power system for a specific site is presented. This design is based on using commercially available components and equipment in an attempt to minimise the total cost of a micro hydro power system. The designed micro hydro power system is installed in-field and the predicted performance of the designed system is verified with measured results of the implemented system. Based on the results of the micro hydro power system landmark example, it is shown through a complete economic study, that this investment is very worthwhile.
AFRIKAANSE OPSOMMING: Die wêreld word daagliks meer en meer uitgedaag om beskikbare alternatiewe energiebronne effektief te benut, nie net om in die groeiende elektrisiteits aanvraag te voorsien nie, maar ook om die beskikbare fossiel brandstowwe te beskerm en ook om die hoeveelheid koolstofdioksied gasse wat deur fossiel brandstof kragstasies vrygestel word, te verminder. Dus het elke beskikbare alternatiewe energiebron, selfs klein riviertjies, ‘n bydrae om te lewer tot die poging om die hoeveelheid elektrisiteit wat deur fossiel brandstowwe opgewek word, te verminder. Die fokus van hierdie studie is op die ontwerp en implementering van ‘n lae koste netwerk gekoppelde 10 kW mikro hidro kragstelsel. Eerstens word die proses om die potensiaal van die beskikbare waterbron te bepaal, bespreek. Al die omgewings aspekte van hierdie mikro hidro kragstelsels word dan bespreek. Dit is ten volle gebaseer op die studies wat gedoen is vir die implementering van hierdie landmerk voorbeeld. Die volledige ontwerp van ‘n mikro hidro kragstelsel, vir ‘n spesifieke terrein, word bespreek. Hierdie ontwerp is hoofsaaklik gebasseer op die gebruik van kommersieel beskikbare komponente met die doel om die totale koste van die stelsel te minimeer. Die stelsel wat ontwerp is, is geïnstalleer op die terrein en die verwagte prestasie van die stelsel is toe geverifieer met gemete resultate van die geïnstalleerde stelsel. ‘n Volledige ekonomiese studie wat gebaseer is op die resultate van die geïnstalleerde stelsel, word dan bespreek en daar is gevind dat hierdie stelsel werklik finansieel die moeite werd is.
Centre for Renewable and Sustainable Energy Studies
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Pastor, Humpiri Carolina Janet. "Estrategias evolutivas no planejamento energetico da operação de sistemas hidrotermicos de potencia." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261841.
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Orientador: Secundino Soares FilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: O objetivo do Planejamento Energético da Operação de sistemas hidrotérmicos de geração é encontrar uma política operativa que forneça energia elétrica ao sistema, em um determinado período de planejamento, com confiabilidade e por um custo mínimo. Isto equivale a determinar um cronograma ótimo de geração para cada usina, a cada intervalo, de modo que o sistema atenda a demanda de forma confiável. Este trabalho faz uso de um dos paradigmas da Computação Evolutiva, as Estratégias Evolutivas (EEs), cuja característica principal é a auto-adaptação dos seus parâmetros durante o processo evolutivo, para a solução do problema de planejamento energético da operação. É feita uma comparação entre as abordagens por EEs e por Programação Não Linear baseada em Fluxo em Redes, para usinas do Sistema Elétrico Brasileiro. As EEs mostraram-se boas ferramentas para apurar a solução fornecida pela programação não linear devido ao elevado poder de exploração do espaço de soluções
Abstract: The objective of the energetic operation planning of hydrothermal generation systems is to find an operation policy that supplies electric energy to the system, during a given planning period, with reliability and by a minimum cost. This is equivalent determining an optimal scheduling of generation for each plant, at each interval, in such a way that the system load is attained with reliability. This work make use of one of the paradigms of Evolutionary Computation, Evolution Strategies (ES), whose main characteristic is the self-adaptation of its parameters during the evolution process, for the solution of the energetic operation planning. A comparison is performed for hydro plants of the Brazilian power system between the ES and the nonlinear network flow approaches. The ES approach turns to be a good tool to improve the solution obtained by the nonlinear programming approach due to its high potential to explore and exploit the solution space
Mestrado
Energia Eletrica
Mestre em Engenharia Elétrica
13
Gomes, Alaise Garcia. "Modelo computacional de cortes para otimizar o potencial de geração de usinas hidrelétricas." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265535.
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Orientador: Paulo de Barros CorreiaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: A repotenciação de usinas hidrelétricas visa aumentar a sua capacidade de geração, realizando melhorias na estrutura das usinas ou troca de equipamentos. É uma alternativa de custos baixos para aumentar a capacidade de geração quando comparada à construção de novos empreendimentos. A repotenciação, foco deste trabalho consiste em substituir as turbinas da usina. Com isto, aumenta-se o rendimento na geração de energia elétrica. No entanto, este rendimento não é constante ao longo da faixa de operação da máquina, podendo ser descrito por curvas, sendo que o formato delas dependente das características da turbina. Nesta dissertação, o objetivo é, dados vários perfis de possíveis curvas de eficiência de novas turbinas, determinar quais as melhores combinações de curvas que otimizariam a geração da usina de acordo com as características operativas da mesma. Para isto, um problema de otimização não linear inteiro misto foi formulado, e um modelo computacional utilizando um método de execução paralelo ao da Decomposição de Benders foi desenvolvido para a resolução do problema de otimização matemática. As simulações foram realizadas com dados fornecidos pela Companhia Hidro Elétrica do São Francisco (CHESF). Concluiu-se que o ideal para os patamares praticados seria uma repotenciação utilizando turbinas com perfis de curvas diferentes e não somente com um perfil
Abstract: The repowering of hydro power plants increases their generating capacity by improving the structure or changing equipment. It is a low cost alternative to improve the generation capacity comparing with the building of new plants. Repowering by changing the hydro-turbines is the focus of this work. By doing that, the efficiency of the energy generation process is improved but, the efficiency is not constant. It can be described by a curve. The curve shape depends on the turbine's characteristics. The aim of this work is, given some possible turbines curve shapes, determine the combination of curves that optimizes the power plant generation according to the plant operational characteristics. A mixed integer nonlinear programming was formulated and a parallel implementation of Bender's decomposition method was developed to solve the problem of mathematical optimization. Simulations were done with data given by the São Francisco's Hydroelectric Company (CHESF). It was concluded that the ideal would be charged to the levels using a repowering turbines with profiles of different curves and not only one profile
Mestrado
Mestre em Planejamento de Sistemas Energéticos
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Martins, Leonardo Silveira de Albuquerque. "Metodo de pontos interiores não-linear para otimização deterministica a usinas individualizadas do planejamento da operação energetica do sistema interligado nacional com restrições de intercambio entre subsistemas." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261136.
Full textAbstract:
Orientadores: Secundino Soares Filho, Anibal Tavares de AzevedoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: A otimização determinística da operação de médio prazo de sistemas hidrotérmicos de potência é um problema não-linear de grande porte. Neste trabalho, ele é resolvido com a devida consideração das restrições de fluxo de intercâmbio energético entre os subsistemas em um único modelo. Para tanto, fez-se necessária a representação explícita do balanço energético, definido como a soma das gerações hidro e termelétrica e do intercâmbio líquido, tal que a demanda de carga seja atendida. As dificuldades algébricas e computacionais impostas pela formulação do problema são contornadas por meio de um método de pontos interiores primal-dual não-linear. Nele, é empregada busca unidimensional com filtro que, dada a implementação proposta, apesar de não garantir convergência global, mostrou-se eficaz em todas as instâncias de testes numéricos realizados, dispensando o uso de funções de mérito. A estrutura esparsa bloco-diagonal das restrições do problema é explorada com vistas à obtenção de melhor desempenho computacional. Resultados dos estudos de caso numéricos para dados reais do sistema elétrico brasileiro sob diferentes configurações são apresentados.
Abstract: This work presents the solution of the medium-term operation scheduling problem for hydrothermal power systems, a complex large-scale nonlinear problem, with consideration of power exchange between interconnected systems. This required the need to explicitly represent the power balance nonlinear equations, defined as the sum of hydro and thermal outputs, and net power imports such that load demand is attained. Algebraic and computational difficulties arisen by the problem formulation are overcome by the use of a nonlinear primal-dual interior-point line search filter method. A line search filter procedure is chosen for these are known to generally outperform penalty merit functions. Although the implementation proposed herein does not guarantee global convergence, it has shown to be very efficient for all numerical tests performed. In addition, the problem's block-constraint structure is exploited for means of improved computational efficiency. Results for diverse numerical tests applied to the Brazilian power system are shown.
Doutorado
Energia Eletrica
Doutor em Engenharia Elétrica
15
Koehler, Marcos. "Impactos no sistema de proteção da rede de distribuição com a ligação de pequenas centrais hidrelétricas." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-11122006-153103/.
Full textAbstract:
Geração Distribuída é uma expressão utilizada para designar a geração elétrica proveniente de locais próximos ou juntos de consumidores, não interferindo a potência, tecnologia ou fonte de energia empregada. Estudos indicam que, até o ano de 2010, 20% do total de geração (em termos mundiais) serão provenientes desta forma de obtenção, uma vez que se torna fático sua vantagem sobre a geração central, por oferecer economia em matéria de investimentos relacionados à transmissão, redução de perdas e melhoria acerca da estabilidade do serviço de energia elétrica. Exemplos de geração distribuída são observados em pequenas centrais hidrelétricas, eólicas, térmicas, fotovoltaicas e geradoras de emergência, por terem pequeno porte e serem integradas ao sistema elétrico. Voltandose por hora ao potencial hidráulico passível de exploração no país, associado por sua vez às pequenas centrais hidrelétricas, tem-se cerca de 4% da potência instalável total (parcela extremamente significativa). De acordo com o Plano 2.015 da ELETROBRÁS, centrais que atingem até 30 MW de potência instalada representam um potencial de 9.456 MW. Informações de Geração da ANEEL indicam que há cerca de 254 PCH em operação no país, totalizando 1327 MW (1,4% do total), 40 empreendimentos em construção (500 MW) e 211 projetos outorgados (construção não iniciada) que, se implantados, adicionarão ao sistema elétrico 3426 MW. O panorama da reordenação da matriz energética nacional não tem apresentado abundância no que diz respeito ao investimento público, direcionado a grandes empreendimentos. Desta forma, as quedas d´água de pequeno e médio porte representam uma evidente opção de geração. As Pequenas Centrais Hidrelétricas (PCH) surgem então como uma alternativa viável, como já especificado anteriormente. Oferece vantagens primeiramente pelo custo acessível, pelo menor prazo de implementação e maturação do investimento, pelas facilidades oferecidas pela legislação, pela disposição das concessionárias de energia elétrica de comprarem o excedente de energia gerada por autoprodutores e finalmente por disponibilizarem o acesso às suas linhas de distribuição e transmissão à longa distância. A partir do incentivo proveniente do Governo Federal para a construção de PCH e descontos nas tarifas de uso dos sistemas de transmissão e distribuição, propiciou-se a ligação de novos pontos de geração de energia no sistema de Distribuição. Com a finalidade de reduzir os custos de transportes de energia, visa-se a localização dos novos pontos de geração próxima aos pontos de consumo potencial. Sendo assim, na medida em que a rede garante a regulação de freqüência e a absorção permanente da potência total, os grupos serão equipados com geradores que não requerem controle com comando sofisticado. Há, todavia, a possibilidade da construção de interligações que devem ser estudadas mesmo quando se tratando de rede de pequeno porte. Sua vantagem está no fato de permitir a utilização de geradores assíncronos, os quais são menos onerosos e mais robustos. Os efeitos da geração nos sistemas de distribuição irão depender do tamanho, do tipo e do local onde será instalada a geração. Atualmente não se tem dado a devida importância aos impactos na proteção da rede de distribuição da concessionária - fato lamentável já que se poderia evitar a degradação da qualidade de energia, confiabilidade e operação - uma vez que se dá prioridade aos benefícios como a energia de backup, a redução dos afundamentos de tensão, a energia de ponta, dentre outras. A partir do momento em que estas PCH são instaladas nas redes de Distribuição, transforma-se um sistema anteriormente radial em um sistema em anel, com mais de uma fonte de contribuição de corrente de curtocircuito. Sendo assim, têm-se como diretrizes deste trabalho abordar temas relacionados aos problemas com falta de coordenação e sensibilidade dos equipamentos de proteção, bloqueio de religamento, necessidade de proteção de sobre-corrente com função direcional, coordenação com consumidores e ramais (gerando problemas de segurança com pessoas e equipamentos) e continuidade de energia. Portanto, é de suma importância a realização sistemática de estudos de proteção de redes com geração de PCH em paralelo, uma vez que é determinante para a segurança e melhoria dos índices de continuidade de serviço. Finalmente, são descritos e analisados detalhadamente, os impactos no sistema de proteção nas redes de distribuição com a ligação de Pequenas Centrais Hidrelétricas, sendo propostas soluções para a redução deste impacto.Distributed Generation is an expression used to designate the electric generation source in places near or contiguous to consumers, regardless of the power, technology or energy source used. Studies show that, by the year 2010, 20% of the total amount of generation (worldwide) will be acquired this way. The advantages of distributed generation, over central generation, are obvious and include: lower investment needed for transmission, reduction of losses and better performance regarding stability in the electric energy service. Examples of distributed generation include: small hydro electrics, wind turbines, thermals, photovoltaics and emergency generators. These examples are small in size and are interconnected to the electric system. Hydraulic power, which is available through exploration in the country, could comprise about 4% of the total power to be generated (which is a verysignificant portion) in small hydro electrics. According to ELETROBRÁS´ Plan 2,015, a power station that reaches up to 30 MW of installed power represents a potential of 9,456 MW. ANEEL´ information about Generation shows that there are about 254 PCH in operation in the country, which total 1,327 MW (1.4% of the total), 40 enterprises under construction (500 MW) and 211 approved projects (construction has not yet begun) that, when finished, will add 3,426 MW to the electric system. Substantial public investments have not been directed toward the larger enterprises since the re-arrangement of the national energy center. Thus, small and medium sized waterfalls represent a very interesting generation option. The small hydro electrics (PCH) appear as a possible choice, as mentioned before. They offer advantages, such as affordable cost, a short implementation time required, return of investment, support through legislation, the willingness of the electric power utilities to buy the exceeded energy generated by selfproducers and, finally, the possibility of access to its distribution and transmission lines through long distances. The connection of new points of energy generation in the Distribution system was made possible with the support from the Federal Government, through encouragement for PCH constructions and tax discounts for use of the transmission and distribution systems. We plan on locating the new points of generation next to the points of potential consumers with the objective of decreasing energy transportation costs. Thus, as the network guarantees the regulation of frequency and the permanent absorption of the total power, groups are equipped with generators that do not require a sophisticated command control. There is, however, the possibility of building interconnections, which must be studied even when related to the small potency network. The advantage lies in the facts that asynchronous generators can be used - which are cheaper and stronger. The effects of generation on distribution systems will depend on size, type and location where the generation will be installed. The protection of the utilities distribution network should be assigned a higher priority. Instead, we prioritize the benefits of energy production, such as the backup energy, voltage sags, top-notch energy, among others. This is unfortunate, since the protection of the utilities distribution network will avoid the degradation of the energy quality, of reliability and of operations. From the moment that these PCH are installed on the Distribution networks, a radial system is turned into a ring system with more than one source of short-circuit current contribution. Thus, the guidelines for this work are the approach to topics related to problems with the lack of coordination and sensibility of protection equipment, re-connection blockage, necessity of protection of overcurrent with directional function, coordination with consumers and extension lines (causing security problems with people and equipment) and energy continuity. It is of great importance to perform systematic studies on the protection of networks with the simultaneous generation of PCH since they are essential for the security and improvement of the current levels of continuity of service. Finally, the impacts on the distribution system protection of networks with connections to Small Hydroelectric Centrals are described and analyzed in detail, followed by proposals of solutions for the reduction of such impacts.
16
Pereira, Andre Flavio Soares. "Planejamento da operação energetica e da manutenção no sistema hidrotermico de potencia brasileiro." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264637.
Full textAbstract:
Orientadores: Sergio Valdir Bajay, Paulo Sergio Franco BarbosaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Nesta dissertação se avalia o estado da arte do planejamento da operação energética e da manutenção de usinas em sistemas hidrotérmicos de potência e se propõe algumas inovações. Neste contexto, se faz uma revisão crítica das metodologias de planejamento empregadas no setor elétrico brasileiro, incluindo as bases de dados que dão suporte a estas metodologias e dando destaque às práticas atuais do Operador Nacional do Sistema Elétrico (ONS); várias propostas de avanços metodológicos são feitas ao longo desta parte do trabalho. Uma outra parte desta dissertação envolve a aplicação de um modelo de otimização, a médio prazo, da operação de algumas usinas do Sistema Interligado Nacional (SIN), pertencentes a uma concessionária geradora no Estado de São Paulo, satisfazendo as metas de geração impostas pelo planejamento centralizado do SIN, realizado pelo ONS, e restrições associadas ao uso múltiplo da água nos reservatórios destas usinas, dentre outras. Várias funções-objetivo podem ser utilizadas neste modelo, dependendo das finalidades a serem atingidas nas simulações. O modelo foi aplicado ao parque gerador hidrelétrico da empresa AES, nos rios Tietê e Pardo; algumas simulações foram feitas, discutindo-se os resultados alcançados
Abstract: The state-of-the-art of power plant scheduling and maintenance planning in hydro-thermal power systems is evaluated in this thesis and some innovations are proposed. In this context, a critical review of the planning methodologies employed in the Brazilian power sector is carried out, including the data bases which support these methodologies and pointing out the current practices of the National Operator of the Power System (ONS); several proposals concerning advances in these methodologies are put forward along this work. In another part of this thesis, the medium-term scheduling of some power stations of the National Interlinked System (SIN) belonging to a utility in the State of São Paulo are modeled through an optimization algorithm, which meets the generation targets imposed by the centralized planning of SIN, carried out by ONS, and constraints associated to multiple uses of water in the reservoirs of these plants, among other constraints. Several objective functions can be used in this model, depending on the purposes to be achieved in the simulations. The model was applied to the hydroelectric generation system of the company AES, in the rivers Tietê and Pardo; some simulations were carried out and their results are discussed in the thesis
Mestrado
Planejamento de Sistemas Energeticos
Mestre em Planejamento de Sistemas Energéticos
17
Cornejo, Gómez César Alberto. "Methodology for the development of hydroelectric power plants." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/107592.
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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, Engineering and Management Program, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 73-75).
Hydropower has sufficient resources available and is actively promoted by Governments as part of their energy matrix, but its development is constrained by the difficulty of addressing location particularities, including technical features such as geology or hydrology, and institutional features such as social acceptance, environmental constraints and the regulatory framework. Project results emerge from the interactions of these Inherent Features and the Project Architecture and do not always meet stakeholders' expectations, leading to deficient project results and lost value. This thesis proposes a methodology for prototyping projects to reflect these particularities and inform project shaping and decision-making early in the process. The proposed methodology was built on three systems engineering and project complexity frameworks, and lessons learned from four case studies. Its contribution to hydropower development is related to (i) the incorporation of systems evolution over time on the development process, (ii) the identification and management of relationships among the various decomposed elements of the development, (iii) the identification of emergent properties from the interactions among all features, (iv) a prototype for developers to optimize or search for project architectures that meet stakeholders objectives while complying with restrictions, (v) the delivery of unbiased information for decision-makers, (vi) the opportunity of stakeholders to participate in the project shaping in a continuous fashion, and (vii) the delivery of a tool for the implementation team to evaluate and challenge changes to the project during construction. The usage of this methodology does not guarantee the avoidance of errors or unforeseen project outcomes, but it does reduce the chance for unknown risks emerging from the interactions of the evaluated features.
by César Alberto Cornejo Gómez.
S.M. in Engineering and Management
18
Almeida, José Leandro Casa Nova. "Análise da viabilidade técnica e econômica de implantação de uma microusina hidrelétrica /." Guaratinguetá : [s.n.], 2007. http://hdl.handle.net/11449/99288.
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Resumo: A proposta desta dissertação foi a de apresentar o desempenho de uma microcentral hidrelétrica, instalada no Centro de Energias Renováveis da Unesp, Campus Guaratinguetá. As análises apresentadas são de desempenho elétrico e mecânico. A microcentral hidrelétrica utiliza roda Pelton com 0,4m de diâmetro no ponto de incidência do jato de água. O gerador utilizado foi com rotor de ímãs permanentes de ferrite. Tanto o gerador quanto a microusina são de baixo custo de aquisição e instalação. Foram feitos os testes em bancada com o gerador aproximando o máximo possível das condições ideais de funcionamento. Também foram realizadas algumas alterações físicas na microhidrelétrica para manter a rotação constante com a variação de carga. Utilizaram-se cargas resistivas e não-lineares. Os resultados contribuíram para a melhoria da qualidade da energia e o controle do fluxo de água no processo de geração de energia. O conjunto composto de gerador e a turbina Pelton, durante o experimento, apresentaram rendimentos eletromecânicos da ordem de 20% a 30% comparados com a teoria.Abstract: This proposal of this work is to demonstrate the performance of a Micro- Hydroelectrical Powerplant (MHP), which has been installed at the UNESP FEG - Renewable Energy Center, in Guaratinguetá-SP. The present analysis refers to the electrical and mechanical performances. The micro-hydroelectrical powerplant employs a Pelton turbine with a diameter of 0,4m at the incidence of water flow. The generator is provided with permanent ferrite magnet rotor. Costs were low for both the acquisition of parts and installation of the generator and the micro-hydroelectrical powerplant. Bench tests carried out with the generator reached the maximum possible ideal functioning conditions. Some physical modifications were necessary to maintain constant rotation with load variations. Resistive and non-linear loads were used in the essays. The results contributed for an improvement in the quality of energy and the control of water flow in the process of generating energy. The assembly composed of the generator and the Pelton turbine presented an electro-mechanical revenue between 20% to 30%.
Orientador: Teófilo Miguel de Souza.
Coorientador: Pedro Magalhães Sobrinho.
Banca: Samuel Euzedice de Lucena.
Banca: Osiris Cancigliere Junior.
Mestre
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Nowakowski, Geórgia Alana Andréas. "Critérios para análise de limites e potencialidades da sustentabilidade de fontes de energia: um estudo da cadeia produtiva das pequenas centrais hidrelétricas no Brasil." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1322.
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Esta pesquisa apresenta como tema de estudo as Pequenas Centrais Hidrelétricas (PCHs). O seu objetivo geral é identificar os principais limites e potencialidades da sustentabilidade da cadeia produtiva de PCHs no Brasil, ao contexto das dimensões ambiental, social, econômica e institucional. O referencial teórico contempla conceitos e questões referentes: a cadeia produtiva; a Teoria do Ator-rede; as fontes de energia renováveis, mais especificamente a hidroeletricidade; e aos fatores determinantes da competitividade. Para a identificação dos gargalos e potencialidades, foi realizado um mapeamento da estrutura da cadeia de produção das PCHs, assim como a descrição do panorama atual das PCHs no país. Em seguida, foram estudadas, de forma mais aprofundada, cinco etapas que compõem a cadeia: recurso natural; geração; transmissão; distribuição; e comercialização. Na sequência, foram utilizados cinco critérios (importância, probabilidade, temporalidade, efeito e abrangência) para classificar os fatores identificados em cada etapa. Por fim, através da multiplicação dos índices numéricos atribuídos aos critérios, foi obtido o Índice de Significância (IS. No que tange à metodologia da pesquisa, ela pode ser classificada como aplicada e exploratória. Os dados empregados são secundários e foi utilizada a técnica de análise qualitativa. Como resultado, foram identificados 20 limites e 17 potencialidades relacionadas com a cadeia produtiva das PCHs no Brasil, sendo que destes 37 itens, 8 foram enquadrados como muito significativos, segundo os critérios estabelecidos para o IS. No que se refere ao resultado principal da pesquisa, verifica-se que, apesar de existirem potencialidades significativas para o desenvolvimento das PCHs na matriz energética nacional (o potencial hidrelétrico das bacias hidrográficas, a sua capacidade de atuar como vetor de desenvolvimento regional, a consolidação dos fabricantes de turbinas e geradores, e o livre acesso), alguns gargalos existentes na sua cadeia de produção devem ser trabalhados, tais como a interferência na migração e reprodução da ictiofauna continental, a desigualdade na distribuição de energia elétrica, e os aspectos legais e técnicos relacionados com o meio ambiente e a comercialização de energia.This research study has as a theme: Small Hydro Power Plants (SHP). Its overall objective is to identify the main limits and potential sustainabilities of the productive chain of power plants in Brazil to the context of environmental, social, economic and institutional dimensions. The theoretical framework includes concepts that concern: the production chain, the Actor-Network Theory, renewable energy sources (specifically hydroelectricity) and the determinants of competitiveness. For the identification of limits and potential, mapping of the production of SHP chain structure was carried out; as well as the description of the current landscape of the SHP in the country. They were then studied in more depth. The five steps that make up the chain being: natural resource, generation, transmission, distribution and commercialization. Next, five criteria were used: importance, likelihood, timeliness, effect and scope; in order to classify the factors identified in each step. Finally, by multiplying the numerical index assigned to the criteria; the significance index (SI) was obtained, which was used to frame the final significance of the aspects by: less significant, significant and very significant. Regarding research methodology; it can be classified as: exploratory and applied. The data used was secondary and was used as qualitative analysis. As a result, we identified 20 potential limits and 17 related to the production chain of power plants in Brazil, and of these 37 items, 8 were classified as very significant, according to the criteria established for the IS. With regard to the main search result, it appears that, although there are significant potential for the development of SHP in the national energy matrix (hydropower potential of river basins, their ability to act as regional development vector, consolidation of turbines and generators manufacturers, and free access), some hurdles in the production chain must be worked out, such as interference in the migration and reproduction of continental fish fauna, inequality in the distribution of electricity, and the legal and technical aspects related to the environment and the commercialization of energy.
20
Rivinoja, Peter. "Migration problems of Atlantic salmon (Salmo salar L.) in flow regulated rivers /." Umeå : Dept. of Aquaculture, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/2005114.pdf.
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Quiroga, Oscar Daniel. "Modelling and nonlinear control of voltage frequency of hydroelectric power plants." Doctoral thesis, Universitat Politècnica de Catalunya, 2000. http://hdl.handle.net/10803/5934.
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Las centrales hidroeléctricas, como sistemas reales, tienen un comportamiento no lineal. Con el objetivo de diseñar controladores para turbinas, fue una práctica normal en el pasado considerar o simplificar estos comportamientos no lineales linealizando en un punto de operación las ecuaciones diferenciales que representan la dinámica de la central hidroeléctrica. La principal motivación de esta tesis nace como consecuencia y la necesidad de mejorar y optimizar las respuestas dinámicas de las plantas hidroeléctricas, considerando estos comportamientos no lineales, conduciendo a modelos dinámicos más realistas del sistema de la turbina hidráulica, además, desarrollar y diseñar controladores más eficientes. Esta tesis considera en general el caso de sistemas de operación aislados, este es el caso de una central hidroeléctrica alimentando una carga aislada. En esta tesis se cubren dos objetivos principales: 1) Profundizar el Conocimiento de los Modelos de Sistemas Hidroeléctricos, 2) Diseñar Controladores a Partir de Modelos Probados.
Profundizar el Conocimiento de los Modelos de Sistemas Hidroeléctricos
Este objetivo consiste en desarrollar un análisis comparativo de diferentes modelos de centrales hidroeléctricas aplicados al control de la velocidad de giro de la turbina, y proponer nuevos modelos. Con este propósito se utilizan parámetros tomados de diferentes centrales hidroeléctricas referenciadas en la bibliografía. Además, se propone la identificación de la central hidroeléctrica de Susqueda (Río Ter, Girona) usando estos modelos previamente refinados. Un paso previo muy importante para el diseño de un controlador es obtener un modelo dinámico de un sistema hidráulico confiable.
Diseñar Controladores a Partir de Modelos Probados
El segundo objetivo es el desarrollo y diseño de controladores de la frecuencia (velocidad de giro) para centrales hidroeléctricas usando técnicas de control no lineal basadas en técnicas de la geometría diferencial y de la función de Lyapunov. En ambos casos los controladores son diseñados a partir de modelos de sistemas hidráulicos no lineales. Los resultados demuestran que usando dos funciones de coste, los controladores no lineales mejoran el comportamiento dado por los clásicos controladores PID entre un veinte y un doce por ciento, y con respecto a un controlador Gain Scheduling la mejora es entre un quince y un doce por ciento.
Hydroelectric power plants, like real systems, have nonlinear behaviour. In order to design turbine controllers, it was normal practice in the past to consider or simplify these nonlinear behaviours by linearizing at an operating point the differential equations that represent the dynamics of the hydroelectric plant. The main motivation of this dissertation was born as a consequence and necessity of improving and optimising the dynamic responses of hydroelectric plants, by taking into account these nonlinear behaviours, leading to more realistic dynamic models of the hydraulic turbine system and to the development and design of more efficient controllers. This dissertation considers in general the case of isolated system operations; it is therefore the case of a hydroelectric power plant supplying an isolated load.
Two objectives are covered in this dissertation: 1) To Deepen the Knowledge of Hydroelectric System Models, 2) To Design Controllers from Well Proven Models.
To Deepen the Knowledge of Hydroelectric System Models
This objective consists of performing a detailed comparative analysis of different existent hydroelectric models applied to speed control and propose new ones. For this purpose real parameters taken from many hydroelectric power plants referenced in the bibliography are utilised.
Moreover, the identification of a hydroelectric power plant on the Ter River (Susqueda) is proposed by using these previously refined models. To obtain a reliable dynamic model of hydraulic turbine systems is an important step prior to the controller design.
To Design Controllers from Well Proven Models
The second objective is the development and design of frequency (speed) controllers for hydroelectric power plants by using nonlinear control techniques based on differential geometry and on the Lyapunov function. For both cases the controllers are designed from nonlinear dynamic models of hydraulic turbine systems. The results demonstrate that using two cost functions the nonlinear controllers improve the behaviour given by classical PID controllers between a twenty and a twelve per cent, and with respect a Gain Scheduling controller the improvement is between a fifteen and a twelve per cent.
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Alford, John Matthew. "The Power Politics of Hells Canyon." Thesis, University of North Texas, 1999. https://digital.library.unt.edu/ark:/67531/metadc278138/.
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This study examines the controversy regarding Hells Canyon on the Snake River, North America's deepest gorge. Throughout the 1950s, federal and private electric power proponents wrangled over who would harness the canyon's potential for generating hydroelectricity. After a decade of debate, the privately-owned Idaho Power Company won the right to build three small dams in the canyon versus one large public power structure. The thesis concludes that private development of Hells Canyon led to incomplete resource development. Further, support of private development led to extensive Republican electoral losses in the Pacific Northwest during the 1950s.
23
Yeung, Hon-chung. "Clean technology advancement in the power industry /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18734765.
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Heffron, Ronald E. "The development and deployment of a submersible ROV for the underwater inspection of hydroelectric station tunnels." Master's thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-01202010-020029/.
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King, Robert Donald 1954. "FEASIBILITY STUDIES FOR SMALL HYDROPOWER PROJECTS (HYDROELECTRIC, PLANNING, RECONNAISSANCE, WATER RESOURCES)." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/292069.
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Cebeci, Mahmut Erkut. "The Effects Of Hydro Power Plants." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609282/index.pdf.
Full textAbstract:
This thesis proposes a method and develops a mathematical model for determining the effects of hydro power plants&rsquogovernor settings on the Turkish power system frequency. The Turkish power system suffers from frequency oscillations with 20 &ndash
30 seconds period. Besides various negative effects on power plants and customers, these frequency oscillations are one of the most important obstacles before the interconnection of the Turkish power system with the UCTE (Union for the Coordination of Transmission of Electricity) network. Taking observations of the system operators and statistical studies as an initial point, the effects of hydro power plants&rsquo
governor settings on the Turkish power system frequency are investigated. In order to perform system wide simulations, initially mathematical models for two major hydro power plants and their stability margins are determined. Utilizing this information a representative power system model is developed. After validation studies, the effects of hydro power plants&rsquo
governor settings on the Turkish power system frequency are investigated. Further computer simulations are performed to determine possible effects of changing settings and structure of HPP governors to system frequency stability. Finally, further factors that may have negative effects on frequency oscillations are discussed. The results of study are presented throughout the thesis and summarized in the &ldquo
Conclusion and Future Work&rdquo
chapter.
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Bergman, Andrew. "Determinants of Fuel Choice in New Electric Power Plants." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/cmc_theses/774.
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Despite increasing fuel cost volatility, regulatory uncertainty, and imminent shifts to industry dynamics, utility managers are forced to make tough decisions in regards to installing long-life generation assets. This study seeks to identify and quantify determinants of fuel choice in new electric power plants given vast uncertainties in the electricity generation sector.
Using a probit functional form to estimate marginal effects on the likelihood of choosing wind versus natural gas powered generation, I find positive effects of natural gas prices in the period three years prior to initial operation of the new facility, positive effects of static-level standard score of mix, and positive effects of wind-power density. Additional feedstock choice sets and parameters are considered.
All models suggest that (a) feedstock costs are significant predictors of fuel choice, (b) state-level regulatory learning enhances likelihood of choosing relatively young technologies, (c) Renewable Portfolio Standards result in artificial substitution between wind and solar technologies, and (d) population density, more so than political influence, predicts choices to install wind-powered capacity. Public policy and managerial implications are discussed.
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Campeau, Benjamin R. "Hydroelectric power optimization using a decomposition procedure for the indefinite quadratic form /." This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09052009-040836/.
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Do, Tung Van. "Optimal operation of a hydroelectric reservoir." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26694.
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This thesis examines the influence of different degrees of serial correlation in the streamflow records on optimal operation of a hydroelectric reservoir. This thesis also investigates the practical aspects of choosing different decision variables, considering effects on ease of implementation, total benefit, and actual use for real-time operations.
Stochastic dynamic programming was used to optimize the long-term operation of a hydroelectric project with a single reservoir. Reservoir inflows were analyzed using monthly flow record for 58 years with the assumption that monthly inflows are either perfectly correlated, uncorrelated, or partially correlated. Reservoir level change and powerhouse discharge were considered as alternative decision variables for each of the three cases of inflow serial correlation. The optimization results were then examined and compared to determine the significance of the choice of decision variables and to explore the effects of inflow serial correlation on practical operating decisions which might be based on the results of the optimization.
It was found that (1) Case 2 in which inflows were assumed perfectly correlated and Case 3 with partially correlated inflows produce, respectively, highest and lowest total expected return, (2) the difference in total expected return between cases depends largely upon the physical characteristics of the system, (3) the reservoir level change decision case produces more conservative results than the discharge decision case, (4) the results from the reservoir level change decision are easier to use for realtime operation than those from the discharge decision case, (5) different results will be produced with different choice of decision variables.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
30
Almeida, José Leandro Casa Nova [UNESP]. "Análise da viabilidade técnica e econômica de implantação de uma microusina hidrelétrica." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/99288.
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A proposta desta dissertação foi a de apresentar o desempenho de uma microcentral hidrelétrica, instalada no Centro de Energias Renováveis da Unesp, Campus Guaratinguetá. As análises apresentadas são de desempenho elétrico e mecânico. A microcentral hidrelétrica utiliza roda Pelton com 0,4m de diâmetro no ponto de incidência do jato de água. O gerador utilizado foi com rotor de ímãs permanentes de ferrite. Tanto o gerador quanto a microusina são de baixo custo de aquisição e instalação. Foram feitos os testes em bancada com o gerador aproximando o máximo possível das condições ideais de funcionamento. Também foram realizadas algumas alterações físicas na microhidrelétrica para manter a rotação constante com a variação de carga. Utilizaram-se cargas resistivas e não-lineares. Os resultados contribuíram para a melhoria da qualidade da energia e o controle do fluxo de água no processo de geração de energia. O conjunto composto de gerador e a turbina Pelton, durante o experimento, apresentaram rendimentos eletromecânicos da ordem de 20% a 30% comparados com a teoria.
This proposal of this work is to demonstrate the performance of a Micro- Hydroelectrical Powerplant (MHP), which has been installed at the UNESP FEG - Renewable Energy Center, in Guaratinguetá-SP. The present analysis refers to the electrical and mechanical performances. The micro-hydroelectrical powerplant employs a Pelton turbine with a diameter of 0,4m at the incidence of water flow. The generator is provided with permanent ferrite magnet rotor. Costs were low for both the acquisition of parts and installation of the generator and the micro-hydroelectrical powerplant. Bench tests carried out with the generator reached the maximum possible ideal functioning conditions. Some physical modifications were necessary to maintain constant rotation with load variations. Resistive and non-linear loads were used in the essays. The results contributed for an improvement in the quality of energy and the control of water flow in the process of generating energy. The assembly composed of the generator and the Pelton turbine presented an electro-mechanical revenue between 20% to 30%.
31
Croll, Geoffrey Edward George. "The economic and policy aspects of small hydro development in British Columbia." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29596.
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Small hydropower offers many advantages as a source of energy and it has been successfully developed by the private sector in the U.S. and in Ontario. Although there is considerable interest in developing British Columbia's vast small hydro resource, there has been very little progress to date. The reasons for this are related more to economic and political factors than to technical issues. In this thesis I review the situation in B.C. and propose a policy framework for energy purchase price, one of the main issues involved in small hydro development. The price offered small hydro producers for their electricity is clearly less than B.C. Hydro's avoided cost, but there is little evidence to support the amount offered. I suggest that, in the absence of an established, competitve market, energy purchase rates should be based on the utility's avoided costs, and that avoided costs be determined by amortizing the capital costs of the next scheduled project over a 20 year period, rather than basing them on the average levelized costs of all future projects. Furthermore, small hydro development should take a two-stage approach, similar to Ontario's, whereby energy is initially purchased at the utility's full avoided cost and later, when the small hydro industry has had a chance to develop, energy would be purchased at market value or through a competitive bidding process.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Jones, I. D. "Assessment and design of small-scale hydro-electric power plants." Thesis, University of Salford, 1988. http://usir.salford.ac.uk/2212/.
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Appraisal and design of small-scale hydro power plants requires a knowledge of hydraulics, hydrology, civil, mechanical, and electrical engineering, and basic economics. Further, small hydro is site specific in nature and marginal from an economic view point. Methods of appraisal and design are required therefore that will keep engineering fees to a minimum and yet still achieve a reliable evaluation of scheme potential and economics. In this context it should be appreciated that small hydro is not large hydro scaled down, and that small hydro needs its own experts (Ref. 1). This thesis considers techniques for appraisal of small hydropower schemes, the selection and specification of scheme components, their costing and economic evaluation. These appraisal techniques are subsequently applied to regional assessment of small-scale hydro-electric potential in the U. K, and to the development and application of a new type of ultra low-head hydropower generator called the Salford Transverse oscillator (STO). Although this work is predominately concerned with assessment of scheme potential in the U.K., it also draws on experience gained by the writer during short visits to India and Nepal, and during a six month design appraisal for rehabilitation of mini-hydro schemes in Sri Lanka (Ref. 2).
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Al-qalawi, Usama. "On estimation of efficiencies of hospitals and electric power plants /." Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1674093241&sid=1&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Thesis (Ph. D.)--Southern Illinois University Carbondale, 2008."Department of Economics." Keywords: Estimation, Hospitals, Electric power plants, Efficiency. Includes bibliographical references (p. 87-93). Also available online.
34
Al-Qalawi, Usama Robin. "On Estimation of Efficiencies of Hospitals and Electric Power Plants." OpenSIUC, 2008. https://opensiuc.lib.siu.edu/dissertations/254.
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AN ABSTRACT OF THE DISSERTATION OF Usama Al-qalawi, For the Doctor of Philosophy degree in Economics, presented on Oct 10th , 2008, at Southern Illinois University Carbondale. TITLE: On Estimation of Efficiencies of Hospitals and Electric Power Plants MAJOR PROFESSOR: Dr. Subhash C. Sharma Our objective of this dissertation was to estimate the efficiencies and the sources of total factor productivity (TFP) of hospitals and the efficiency of electrics power plants. In addition, we investigate the effect of some factors that are associated with the variation in efficiency. A translog functional form is estimated using Stochastic Frontier analysis. Then we decompose productivity growth to its main components: the economic of scale effect, the technical progress effect and the change in inefficiency effect. The dissertation is divided to three main subjects. The first subject is about Californian hospitals, the second one is about Veterans hospitals and the last one is about the electricity power plants. The results indicate that the average cost efficiency of Californian hospitals is 90.0% during the period between 1995 and 2005. It implies that those hospitals on average have a cost about 10% above the cost frontier that represent the minimum possible cost. Furthermore, the state of California lost $ 3.28 billion a year on average as consequence of this cost inefficiency. The results also indicate that inefficiency increases over time and by raising the unoccupied beds. In addition, the results suggest that inefficiency decreases as the severity of inpatient increases, and is lower for psychiatric, big and DSH reporting hospitals. The average cost efficiency of the V.A. Hospitals was 81.39 % during the period 2003 and 2007. The average annual total cost for VA hospitals during the period of study was $ 27.4 billion; out of which $ 5.4 billion can be attributed to inefficiency. Further more, the total annual cost of VA hospitals rise during the period of the study from $ 23.3 billion to $ 31.15 billion. With average growth rate equal to 7.53 %. Cost efficiency of Californian hospitals increased during the period between 2003 and 2006 while it slightly decreases in the 2007. Moreover, a concave relation between the number of beds and the efficiency of VA hospitals are founded. As the number of beds increases, efficiency of hospitals increases until it reaches the highest point of efficiency when hospitals have between 100 and 149 beds. Then, it goes back down until it reaches its lowest value for hospitals that have more than 350 beds. Furthermore, average growth of TFP was -0.0320 during the period of study and this suggests that productivity of VA hospitals decreases due to technological recess. The results specify that the technical efficiency of electric power plants was 23.63%. Moreover, it indicates that older plants are more inefficient, and inefficiency will be lower for those plants that face higher net peak demand and have smaller size measured by the maximum generator name plate. In addition, we found that storage plants are more efficient than hydro electric plants and the latter plants are more efficient than renewable energy plants and all are more efficient than fossil energy fueled plants. Furthermore, we found that the most efficient generators are associated with gulf cooling water, used closed-loop cooling systems and are using a mix of petroleum and renewable fossil material as a fuel.
35
Palu, Ivo. "Impact of wind parks on power system containing thermal power plants = Tuuleparkide mõju soojuselektrijaamadega energiasüsteemile /." Tallinn : TUI Press, 2009. http://digi.lib.ttu.ee/i/?443.
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Payne, Jill Rowan. "Land-use and landscape : hydroelectricity and landscape protection in the Highlands of Scotland, 1919-1980 /." St Andrews, 2008. http://hdl.handle.net/10023/562.
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Kim, Young-Oh. "The value of monthly and seasonal forecasts in Bayesian stochastic dynamic programming /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/10142.
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Smyth, Thomas Paton. "A review of the emergency electric power supply systems at PWR nuclear power plants." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/22430.
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Bibliography: pages 168-174.The Emergency Electric Power Supply Systems at Pressurized Water Reactor Nuclear Power Plants are reviewed, problem areas are identified, and recommendations are made for existing and future Nuclear Power Plants. A simplified introduction to a typical Pressurized Water Nuclear Reactor is given and the problems associated with the commercial use of nuclear power are discussed. An overview of the Nuclear industry's solutions is presented and covers the Reliability of equipment and the American Regulatory requirements. The alternating and direct current power supply systems are examined in terms of plant operational state and equipment type (Diesel generators, Grid network, Lead-acid batteries, Battery chargers, Inverters, and Power Distribution networks). The trends in the design of Emergency Electric Power supply systems at Nuclear Power Plants are presented. The loss of all alternating current power, known as Station Blackout, is discussed and the American and European response to this. problem is presented. Problems experienced in the direct current systems are discussed and solutions are presented. The experience at Koeberg Nuclear Power station with Lead-acid batteries is included in the discussion. The thesis concludes with recommendations for designers and operators of the Electric Power Supply Systems at Nuclear Power Stations.
39
Balci, Huseyin Hakan Valenzuela Jorge F. "Valuation of power generation investments in deregulated capacity markets." Auburn, Ala., 2008. http://repo.lib.auburn.edu/2007%20Fall%20Dissertations/Balci_Huseyin_36.pdf.
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Williams, Arthur A. "Pumps as turbines used with induction generators for stand-alone micro-hydroelectric power plants." Thesis, Nottingham Trent University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262127.
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香旭勳 and Yok-fun Heung. "Defect records analysis in Tsing Yi Power Station." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B31975835.
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Kaymaz, Pinar Valenzuela Jorge F. "Electric power generation expansion in deregulated markets." Auburn, Ala., 2007. http://repo.lib.auburn.edu/Send%2002-04-08/KAYMAZ_PINAR_52.pdf.
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Khaliq, Abdul. "Preventive control for the attainment of a dynamically secure power system." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/13893.
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Amakali, Simakeka. "Development of models for short-term load forecasting using artificial neural networks /." [S.l. : s.n.], 2008. http://dk.cput.ac.za/cgi/viewcontent.cgi?article=1031&context=td_cput.
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45
Campeau, Benjamin R. Jr. "Hydroelectric power optimization using a decomposition procedure for the indefinite quadratic form." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/44609.
Full textAbstract:
The optimization of hydroelectric power is one area of water resources
management where the implementation of supply management techniques could yield enormous social welfare benefits. A broad spectrum of computer modeling and analysis techniques have been applied to the hydroelectric power production model in an attempt to improve the real-time operation of reservoir systems. The nonconvex, nonseparable hydropower objective function poses a formidable task in devising a global optimization scheme. A decomposition procedure for the indefinite quadratic form is used to develop an algorithm that will find a near global optimum of a nonlinear hydroelectric power optimization model. The decomposition scheme, due to Pardalos et aI., splits the indefinite quadratic form into separable concave and convex parts. A Taylor series approximation is applied to the concave part, which, along with the separated convex part, is a convex underestimating problem (minimization) that can be solved efficiently. The decomposition technique is applied to two models of reservoir systems within the Upper Green River Basin and the models are solved using the GAMS/MINOS computer code. A comparison of the results obtained from successive linear programming, a fixed head linearization strategy, and direct nonlinear optimization of the nonconvex objective, with the results of the decomposition procedure, indicates the new algorithm has advantages over these techniques.Master of Science
46
Lin, Martin Wei-min. "A model and simulation of competitive electric power systems /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Parnandi, Silpa. "Power market analysis tool for congestion management." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5187.
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Thesis (M.S.)--West Virginia University, 2007.Title from document title page. Document formatted into pages; contains viii, 71 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 68-71).
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Matavalam, Roop Kishore R. "Power distribution reliability as a function of weather." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0006668.
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Chao, Xingyong H. "Nondivergent and optimal power flow : a unified approach." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/15499.
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McCalley, James D. "A methodology for determining the effects of non-utility generation on inter-area oscillations in electric power systems." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/16023.
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