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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Análise de Viabilidade de Projetos de Pequenas Centrais Hidrelétricas: Pontos Críticos de Sucesso a Partir de Estudos de Caso no Estado de Santa Catarina / Feasibility Analysis of Small Hydro Power Projects: Critical Points of Success Drawn from Case Studies in the State of Santa Catarina.

Makaron, Paula Matos 14 May 2012 (has links)
MAKARON, Paula. Análise de Viabilidade de Projetos de Pequenas Centrais Hidrelétricas: Pontos Críticos de Sucesso a Partir de Estudos de Caso no Estado de Santa Catarina. 2012. 144f. Dissertação (Mestrado em Energia) - Programa de Pós-Graduação Em Energia - EP/FEA/IEE/IF da Universidade de São Paulo, São Paulo 2012. Esta dissertação analisa os pontos críticos de sucesso de projetos de Pequenas Centrais Hidrelétrica da perspectiva econômico-financeira. Para tal, foram percorridas três etapas. A primeira delas visou à análise dos contextos mundial e nacional desse segmento de geração de energia, seguindo os conceitos técnicos que caracterizam os empreendimentos de geração hidrelétricos de pequeno porte. Nessa etapa analisou-se o processo de implementação de uma PCH, desde o levantamento de potencias de aproveitamento de um rio até a sua entrada em operação comercial. A segunda etapa debruçou-se sobre a metodologia aplicada no cálculo da viabilidade de um projeto de infraestrutura e as adequações metodológicas necessárias para o caso de uma usina de pequeno porte. Tais adequações incluíram a seleção de componentes específicos do fluxo de caixa e de critérios para a escolha das variáveis-chave em projetos de PCHs. Outro importante conceito discutido nessa etapa foram os riscos inerentes a esses projetos e a forma como a materialização de cada risco pode afetar seus resultados. Por fim, na terceira etapa, à luz da teoria previamente visitada nas fases anteriores, foram analisados dois estudos de casos práticos de projetos reais localizados no Estado de Santa Catarina. Tais estudos de caso incluíram a análise de viabilidade para: (a) a construção da PCH Fartura e (b) a aquisição da PCH Santa Ana, estando essa última já em operação comercial. Em ambos os estudos foram testadas variações de algumas premissas tais como: o preço de venda da energia; o custo do capital; e aumento do custo da construção. Da análise realizada foi possível concluir que, no cenário do período estudado, a construção de uma PCH não é viável, o preço praticado nos ambientes livre e regulado de contratação não tem sido suficiente para pagar os investimentos realizados. Por outro lado, a compra de uma usina já em operação comercial se mostrou um ótimo negócio, uma vez que os principais riscos do período de construção já haviam sido superados no e a usina apresentava fluxo de receita garantido. Como as variáveis analisadas permeiam a maioria dos projetos de PCH, estima-se que este trabalho possa contribuir para o melhor entendimento da crise que o segmento de geração de pequenas usinas vem atravessando no Brasil nesses anos compreendidos entre 2008 e 2012. / MAKARON, Paula. Feasibility Analysis of Small Hydro Power Projects: Critical Points of Success Drawn from Case Studies in the State of Santa Catarina. 2012. 144f. Masters Dissertation Graduate Program on Energy, Universidade de São Paulo, São Paulo, 2012. This dissertation analyzes critical points of success of projects in Small Hydro Power Plants (SHP) from the economic/financial perspective. For this, three stages were drawn up. The first aimed at the analysis of world and national contexts of this segment of energy generation following the technical concepts which characterize the small-sized hydroelectric generating businesses. During this stage, the implementation process of a SHP was analyzed; starting with the survey of the potential of a river until the plant enters into commercial operation. The second stage focused on the methodology applied to calculating the viability of an infrastructure project and the necessary methodological adjustments for a small-sized plant. These adjustments include a selection of components specific to the cash flow and the criteria for choosing key-variants in SHC projects. Another important concept discussed during this stage was the inherent risks involved in these projects and the way in which each risk can affect the results. Finally, during the third stage, in light of the theory reviewed in previous stages, two practical case studies of real projects from the state of Santa Catarina were analyzed. Such case studies included the viability analysis for decision making regarding: (a) the construction of the SHP Fartura and (b) the acquisition of the SHP Santa Ana, the latter already in full commercial operation. In both studies, it was tested a variation of some key elements such as: the price of energy; the capital cost; the cost overruns. From the aforementioned analysis, it was possible to conclude that in studied scenario, the construction of a SHP is not viable. The energy price level in the free hiring and in the regulated environments has not been sufficient to pay back original investment. On the other hand, buying a plant already in commercial operation proved to be a good business proposition, once the main development risks during the construction period had been overcome and the plant presented a flow of guaranteed income. Seeming as the variables permeate most SHP projects, it is foreseen that this work can contribute to the better understanding of the crisis in which this segment of small generation plants are going through here in Brazil during the years 2008 to 2012.
2

Implementation of Hydro Power Plant Optimization for Operation and Production Planning

Tengberg, Oskar January 2019 (has links)
Output power of hydro power plant was modelled and an optimization algorithm was implemented in a tool for optimizing hydro power plants. The tool maximizes power output of a hydro power plant by distributing water over a set of active units in the power plant which will be used in planning of electricity production. This tool was built in a MATLAB environment, using the optimization toolbox, and a GUI was developed for Vattenfall. The optimization tool was based on the same architecture as the current tool used for this kind of optimization which is to be replaced by the work presented in this thesis. Therefore, the goal was to achieve the same optimal results as the current optimization tool. Power output of three of Vattenfall’s hydro power plants were computed and two of these plants were optimized. These power output results were compared to results from the optimization tool currently used. This showed differences within the inaccuracy of measurements of ≤ 0.3%. These three power plants proved that the new tool is sufficient to replace the current tool but further testing is recommended to be conducted on more of Vattenfall’s hydro power plants to prove its consistency.
3

Análise de Viabilidade de Projetos de Pequenas Centrais Hidrelétricas: Pontos Críticos de Sucesso a Partir de Estudos de Caso no Estado de Santa Catarina / Feasibility Analysis of Small Hydro Power Projects: Critical Points of Success Drawn from Case Studies in the State of Santa Catarina.

Paula Matos Makaron 14 May 2012 (has links)
MAKARON, Paula. Análise de Viabilidade de Projetos de Pequenas Centrais Hidrelétricas: Pontos Críticos de Sucesso a Partir de Estudos de Caso no Estado de Santa Catarina. 2012. 144f. Dissertação (Mestrado em Energia) - Programa de Pós-Graduação Em Energia - EP/FEA/IEE/IF da Universidade de São Paulo, São Paulo 2012. Esta dissertação analisa os pontos críticos de sucesso de projetos de Pequenas Centrais Hidrelétrica da perspectiva econômico-financeira. Para tal, foram percorridas três etapas. A primeira delas visou à análise dos contextos mundial e nacional desse segmento de geração de energia, seguindo os conceitos técnicos que caracterizam os empreendimentos de geração hidrelétricos de pequeno porte. Nessa etapa analisou-se o processo de implementação de uma PCH, desde o levantamento de potencias de aproveitamento de um rio até a sua entrada em operação comercial. A segunda etapa debruçou-se sobre a metodologia aplicada no cálculo da viabilidade de um projeto de infraestrutura e as adequações metodológicas necessárias para o caso de uma usina de pequeno porte. Tais adequações incluíram a seleção de componentes específicos do fluxo de caixa e de critérios para a escolha das variáveis-chave em projetos de PCHs. Outro importante conceito discutido nessa etapa foram os riscos inerentes a esses projetos e a forma como a materialização de cada risco pode afetar seus resultados. Por fim, na terceira etapa, à luz da teoria previamente visitada nas fases anteriores, foram analisados dois estudos de casos práticos de projetos reais localizados no Estado de Santa Catarina. Tais estudos de caso incluíram a análise de viabilidade para: (a) a construção da PCH Fartura e (b) a aquisição da PCH Santa Ana, estando essa última já em operação comercial. Em ambos os estudos foram testadas variações de algumas premissas tais como: o preço de venda da energia; o custo do capital; e aumento do custo da construção. Da análise realizada foi possível concluir que, no cenário do período estudado, a construção de uma PCH não é viável, o preço praticado nos ambientes livre e regulado de contratação não tem sido suficiente para pagar os investimentos realizados. Por outro lado, a compra de uma usina já em operação comercial se mostrou um ótimo negócio, uma vez que os principais riscos do período de construção já haviam sido superados no e a usina apresentava fluxo de receita garantido. Como as variáveis analisadas permeiam a maioria dos projetos de PCH, estima-se que este trabalho possa contribuir para o melhor entendimento da crise que o segmento de geração de pequenas usinas vem atravessando no Brasil nesses anos compreendidos entre 2008 e 2012. / MAKARON, Paula. Feasibility Analysis of Small Hydro Power Projects: Critical Points of Success Drawn from Case Studies in the State of Santa Catarina. 2012. 144f. Masters Dissertation Graduate Program on Energy, Universidade de São Paulo, São Paulo, 2012. This dissertation analyzes critical points of success of projects in Small Hydro Power Plants (SHP) from the economic/financial perspective. For this, three stages were drawn up. The first aimed at the analysis of world and national contexts of this segment of energy generation following the technical concepts which characterize the small-sized hydroelectric generating businesses. During this stage, the implementation process of a SHP was analyzed; starting with the survey of the potential of a river until the plant enters into commercial operation. The second stage focused on the methodology applied to calculating the viability of an infrastructure project and the necessary methodological adjustments for a small-sized plant. These adjustments include a selection of components specific to the cash flow and the criteria for choosing key-variants in SHC projects. Another important concept discussed during this stage was the inherent risks involved in these projects and the way in which each risk can affect the results. Finally, during the third stage, in light of the theory reviewed in previous stages, two practical case studies of real projects from the state of Santa Catarina were analyzed. Such case studies included the viability analysis for decision making regarding: (a) the construction of the SHP Fartura and (b) the acquisition of the SHP Santa Ana, the latter already in full commercial operation. In both studies, it was tested a variation of some key elements such as: the price of energy; the capital cost; the cost overruns. From the aforementioned analysis, it was possible to conclude that in studied scenario, the construction of a SHP is not viable. The energy price level in the free hiring and in the regulated environments has not been sufficient to pay back original investment. On the other hand, buying a plant already in commercial operation proved to be a good business proposition, once the main development risks during the construction period had been overcome and the plant presented a flow of guaranteed income. Seeming as the variables permeate most SHP projects, it is foreseen that this work can contribute to the better understanding of the crisis in which this segment of small generation plants are going through here in Brazil during the years 2008 to 2012.
4

MAXIMIZATION OF ENERGY GENERATION FROM SMALL HYDROPOWER PLANTIN SRI LANKA : - / MAXIMIZATION OF ENERGY GENERATION FROM SMALL HYDROPOWER PLANTIN SRI LANKA : -

PATHIRANAGE, GUMINDA SANJEEWA PRIYADARSHANA January 2014 (has links)
Sri Lanka has a number of small waterfalls and channels. Related to this there is a significant potential to develop small hydropower plants, thus to generate much needed electricity for country’s development efforts. Small hydro power plants cause less environmental effects compared to large scale hydro power generation and power generation using fossil fuel. Therefore, it is a timely requirement to explore the possibilities of utilizing small water streams to generate electricity as much as possible as well as to optimize the energy generation with the available    water in those water streams.   The importance of small hydro power is highlighted in the   Sri Lanka’s energy generation plan, and  the Ceylon Electricity Board (CEB) annual report states that in year 2011 total installed capacity of small hydro plant was around 200MW and it is expected to expand energy generation to around 800GWh. This study focuses on finding out optimum operating parameters to maximize the energy generation of existing small hydro power plant in the country. By selecting a few small hydro power plants, preliminary studies were performed to identify optimum values of water flow rate to maximize the efficiency of the power generation. The study revealed that the selected plants had not operated at the maximum efficiency; hence they did not optimally utilize the available water.
5

Crack initiation in hydro power plant rotor rim sheets : A failure case study for Juktan hydro power plant

Altzar, Oskar January 2014 (has links)
In 2013, cracks were found in the radius of the dovetail slots of the rotor rim sheets in generator 1 of Juktan hydro power plant in Västerbotten, Sweden. The cracks were estimated to be too deep to be able to repair and Alstom conducted an investigation on the cause of fracture. The investigation came to the conclusion that the radius was too small and that the new rotor rim sheets should have a six times greater fillet radius. However, it has not been investigated whether the material structure or the manufacturing process may have an impact on the crack initiation and following propagation that is the focus of this report.Parts of the dovetail slots were cut out and characterized with XRF, SEM and LOM. Further mechanical characterizations were done according to Vickers.From the SEM and LOM micrographs a high amount of large (10μm) and cubic particles were found in the microstructure. The micrographs also showed a deformation of the microstructure and the hardness test showed a deformation hardening near the edge where the sheet had been punched. The edge surface of the sheet also had notches.The large and hard particles in the microstructure impair the mechanical properties of the steel. Furthermore, the hardening effect combined with the notches will make a good crack initiation point. Therefore, there is a higher possibility that a crack will initiate in the radius of the dovetail slots where large stresses occur.
6

Tvorba a estimace modelu malé vodní elektrárny v programu PSCAD / Creation and estimation of small hydro power plant model in PSCAD

Razyapova, Aygul Unknown Date (has links)
This thesis focused on creating a model of a small hydropower plant model (SHPP) and a part of the electricity network in the simulation software "PSCAD" (basing on real sources). The model will be specified on the basis of the data obtained from the measurements to correspond with the real equipment.
7

Gestion Optimale d’une installation hybride au Vietnam / Optimal Management of a hybrid installation in Vietnam

Pham, Duy An 11 July 2018 (has links)
Le Vietnam est un pays en voie d’industrialisation rapide ce qui engendre une croissance élevée des besoins énergétiques. La consommation énergétique du Vietnam est en augmentation mais pas de façon égale dans tout le pays. En effet, 66.9% de la population du Vietnam vit en zone rurale en 2014. Une grande partie de la population vit encore pauvrement dans des sites isolés avec des accès très restreint aux énergies. Le Vietnam Master Power Plan VII (2011) indique que 759.986 habitations n’ont pas accès à l’électricité.Cependant, le Vietnam est un pays qui possède un grand potentiel en énergie renouvelable (l’énergie solaire, l’énergie éolienne, l’énergie hydroélectrique, l’énergie Biomasse). Le Vietnam a élaboré une stratégie de développement des énergies renouvelables, afin de mobiliser toutes les ressources pour réduire la dépendance aux combustibles fossiles. Les sites isolés se situent principalement au Nord-Ouest du Vietnam, près de la frontière avec le Laos et la Chine, où il existe un grand potentiel d’énergie hydraulique et/ou solaire. Il faut quand même signaler que ces énergies sont souvent saisonnières et, par exemple, une microcentrale hydroélectrique ne peut pas satisfaire la demande en énergie électrique lors de la saison sèche. Donc, un système utilisant deux sources d’énergies renouvelables (panneaux photovoltaïques et microcentrale hydroélectrique) est l’une des solutions optimales pour alimenter en électricité un site isolé au Vietnam. L’objectif de cette thèse est la gestion optimale de l’électricité renouvelable d'un tel système.Afin de satisfaire à une utilisation maximale, le principe de suivi du point maximum (ou Maximum Power Point Tracking – MPPT) est mis en application. Pour la chaine de conversion photovoltaïque, un contrôleur flou à une entrée est proposé afin de suivre le point de puissance maximale du panneau solaire.Pour la chaine de conversion hydroélectrique, une turbine Pelton couplée à un générateur synchrone à rotor bobiné permet d’alimenter en électricité une charge triphasée. Une plateforme d'essais est réalisée dans le laboratoire CReSTIC, IUT de Troyes pour effectuer une validation expérimentale du système de régulation d’une Microcentrale hydroélectrique.Pour la réalisation d’un système de production d’électricité hybride, un superviseur flou est conçu pour obtenir un comportement optimal du système. Après, une étude sur les avantages et inconvénients de ce type de systèmes hybrides pour un site isolé a été effectuée (amélioration de la formation des adultes, augmentation du temps de travail pendant la nuit, réduction du coût du carburant).Ce travail contribue à la connaissance d'une gestion optimale des énergies renouvelables pour site isolé en révélant les avantages et les qualités de l’utilisation des ressources d’énergie renouvelables au gouvernement et à d’autres investisseurs locaux ou internationaux au Vietnam. / As a rapidly industrializing country, the economy of Vietnam's has become very energy intensive. Thought, 66.9% of Vietnam's population lives in rural area in 2014. Many people still live in remote farming areas that are stricken with poverty. The Vietnam Master Power Plan VII (2011) indicates that still 818,947 households are not connected to the national grid, and 759,986 households do not have any access to electricity.Vietnam has high potential on renewable energy resources (Wind, Solar, Hydro, Biomass, and Geothermal). Using hybrid renewable energy system is considered to be one of the most feasible options to bring electricity to local people to improve life quality. The off-grid communities in Vietnam are located mainly in the north-west of Vietnam, near the border with Laos and China, where exist a great potential on Hydro power and/or solar power. A micro hydro power plant cannot satisfy the load demand, especially in dry season. Therefore, additional energy sources such as PV arrays have been suggested to complement power efficiency. Thus, this working discusses the pre-feasibility for small hybrid power generation system consisting of a PV generating unit with storage and a micro hydro generation unit for off-grid areas in Vietnam.The objective of this thesis is to optimize the production of renewable electricity for this type of small hybrid power generation system. For the photovoltaic conversion system, a one input fuzzy logic controller for maximum power point tracking is designed. For the Micro-hydro power plants (MHPP), a Pelton turbine is coupled to a would rotor synchronous generator to supply electricity for a three phase load. To keep the MHPP frequency and voltage outputs constant (50 Hz, 230 V) in spite of changing user loads, the controller is necessary. The experimental results of MHPP frequency and voltages control show the ability of our controller. For the realization of small hybrid power generation, a fuzzy supervisor is adapted to obtain an optimal behavior of the system. Finally, a study on the advantages of this type of hybrid system is carried out (improvement of adult training, increased night working hours, and reduction fuel costs). This thesis contributes to the knowledge of Renewable Energy (RE) by revealing the suitable usability and prospects of RE resources to the government and other local or international investors in Vietnam.
8

Vyhodnocení efektivnosti investic obnovitelných zdrojů energie na příkladu malých vodních elektráren / Evaluation of Investment Effectiveness on the Field of Renewable Sources by the Examples of Small Hydro Plants

Pavlíčková, Eva January 2011 (has links)
Thesis deals with the use of renewable sources of energy focused on water energy, especially small hydropower plants in Czech Republic. It should clarify the legal and technical framework for energy production in small hydro power plants, types of aid and the amount for the operator. Case studies describe the construction and reconstruction of small hydroelectric power plants which are dependant on the amount of feed-in tariffs and try to find out the economic efficiency according to the selected methods of investment appraisal.
9

Reconfiguração de redes de distribuição em situações de contingências considerando operação ilhada de PCH / Reconfiguration of distribution network in contingency conditions considering islanded operation of small hydro power plant

Lopes, Guilherme Stivanin 22 August 2014 (has links)
One of the main concerns of the power utilities is secure, continuously supplying electric power to customers, thus meeting so satisfy these as to regulatory requirements. Thus, the proposed paper presents a method of restoring the electric power supply applying the concepts of automatic reconfiguration of the aggregate distribution networks the possibility of islanded operation of small hydro (SHP), since the use of PCH so islanded in certain circumstances, or becomes only, or the best solution to be adopted in a contingency situation in order to reduce the impact of unwanted interruptions. Since the intrinsic decision making process of reconfiguration of distribution networks involves multiple objectives and constraints, the proposed methodology uses the Analytic Hierarchy Process (AHP) method, which is a very useful tool for issues involving multicriteria decision taken. Additionally, case studies for analysis and validation of the proposed methodology are presented. / Uma das principais preocupações das empresas distribuidoras de energia elétrica é garantir, de forma contínua, o fornecimento de energia elétrica aos seus clientes, atendendo assim tanto a satisfação desses quanto às exigências regulatórias. Sendo assim, o trabalho proposto visa apresentar uma metodologia de restabelecimento do fornecimento de energia elétrica aplicando os conceitos de reconfiguração automática das redes de distribuição agregados a possibilidade de operação ilhada de pequenas centrais hidroelétricas (PCHs), uma vez que a utilização de PCH de forma ilhada, em determinadas circunstâncias, torna-se ou a única, ou a melhor solução a ser adotada em uma situação de contingência com o objetivo de reduzir o impacto causado por interrupções indesejadas. Visto que a tomada de decisão intrínseca ao processo de reconfiguração das redes de distribuição envolve vários objetivos e restrições, a metodologia proposta utiliza o método Analytic Hierarchy Process (AHP) que representa uma ferramenta muito útil para questões envolvendo tomadas de decisão multicriteriais. Adicionalmente, são apresentados estudos de caso para análises e validações da metodologia proposta.
10

Tvorba a estimace modelu malé vodní elektrárny v programu PSCAD / Creation and estimation of small hydro power plant model in PSCAD

Razyapova, Aygul January 2016 (has links)
This thesis focused on creating a model of a small hydropower plant model (SHPP) and a part of the electricity network in the simulation software "PSCAD" (basing on real sources). The model will be specified on the basis of the data obtained from the measurements to correspond with the real equipment.

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