Дисертації з теми "Optimization of reactive power"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "Optimization of reactive power".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Radibratovic, Branislav. "Reactive optimization of transmission and distribution networks." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/28264.
Повний текст джерелаCommittee Chair: Begovic, Miroslav; Committee Member: Divan, Deepakraj; Committee Member: Dorsey, John; Committee Member: Ferri, Bonnie; Committee Member: Lambert, Frank.
Ibrahim, Sarmad Khaleel. "DISTRIBUTION SYSTEM OPTIMIZATION WITH INTEGRATED DISTRIBUTED GENERATION." UKnowledge, 2018. https://uknowledge.uky.edu/ece_etds/116.
Повний текст джерелаMaroufi, Seyede Masoome. "Optimization of active and reactive power in smart buildings using a distributed model predictive control." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Знайти повний текст джерелаPhulpin, Yannick Dominique. "Coordination of reactive power scheduling in a multi-area power system operated by independent utilities." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31638.
Повний текст джерелаCommittee Chair: Begovic, Miroslav; Committee Member: Divan, Deepak; Committee Member: Harley, Ron; Committee Member: Petit, Marc; Committee Member: Verriest, Erik. Part of the SMARTech Electronic Thesis and Dissertation Collection.
Wang, Zhongkui. "Reactive Power Control and Optimization of Large Scale Grid Connected Photovoltaic Systems in the Smart Grid." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1388764166.
Повний текст джерелаLi, Xiaofan. "Design, Analysis and Testing of a Self-reactive Wave Energy Point Absorber with Mechanical Power Take-off." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/100800.
Повний текст джерелаDoctor of Philosophy
Ocean wave as a renewable energy source possesses great potential for solving the world energy crisis and benefit human beings. The total theoretical potential wave power on the ocean-facing coastlines of the world is around 30,000 TWh, although impossible to be all transferred into electricity, the amount of the power can be absorbed still can cover a large portion of the world's total energy consumption. However, multiple reasons have stopped the ocean wave energy from being widely adopted, and among those reasons, the most important one is immature of the Power Take-off (PTO) technology. In this dissertation, a novel two body wave energy converter with a PTO using the unique mechanism of Mechanical Motion Rectifier (MMR) is investigated through design, analysis, and testing. To improve the energy harvesting efficiency and the reliability of the PTO, the dissertation induced a mechanical PTO that uses MMR mechanism which can transfer the reciprocated bi-directional movement of the ocean wave into unidirectional rotation of the generator. This mechanism brings in a unique phenomenon of engagement and disengagement and a piecewise nonlinear dynamic property into the PTO. Through a comprehensive study, the MMR PTO is further characterized and a refined dynamic model that can accurately predict the dynamic response of the PTO is established. The major factors that can influence the performance of the MMR PTO are explored and discussed both analytically and experimentally. Moreover, as it has been theoretically hypothesis that using a two-body structure for designing the point absorbers can help it to achieve a frequency tuning effect for it to better match with the excitation frequency of the ocean wave, it lacks experimental verification. In this dissertation, a scaled two-body point absorber prototype is developed and put into a wave tank to compare with the single body structure. The test results show that through the use of two-body structure and by designing the mass ratio between the two bodies properly, the point absorber can successfully match the excitation frequency of the wave. The highest power capture width ratio (CWR) achieved during the test is 58.7%, which exceeds the results of similar prototypes, proving the advantage of the proposed design.
Stypulkowski, Yuri Solis. "Alocação ótima de compensação de potência reativa." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/165244.
Повний текст джерелаThis work proposes a methodology to enumerate solutions, which indicate the bar and the reactive power compensation required for the electrical system under analysis, that meet the requirements evaluated by the objective function and the constraints. In this allocation of optimal compensation of reactive power, we obtain the optimal bars and technologies of compensation devices, minimizing the total losses of active power of the network. In weak networks with frequency converters (e.g. for connection of renewable sources, or interconnections using HVDC converters), the proposed methodology seeks the best threephase short-circuit (SCR) relation at the connection point, improving the connection of the new generation. The method looks for solutions to allocate a single compensation device, and solutions to allocate two devices simultaneously. The proposed methodology is based on the exhaustive enumeration of the solutions. A case study carried out in the IEEE 14 and 30 bus systems shows the applicability and performance of the proposed methodology.
Moghadasiriseh, Amirhasan. "Analysis and Modeling of Advanced Power Control and Protection Requirements for Integrating Renewable Energy Sources in Smart Grid." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2469.
Повний текст джерелаAlcântara, Márcio Venício Pilar 1978. "Alocação de capacitores em sistemas de distribuição de energia eletrica." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259439.
Повний текст джерелаDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
Made available in DSpace on 2018-08-04T07:50:24Z (GMT). No. of bitstreams: 1 Alcantara_MarcioVenicioPilar_M.pdf: 1100908 bytes, checksum: 0913d60c47bc87e4c67320408f6905af (MD5) Previous issue date: 2005
Resumo: É sabido que o maior volume de perdas ocorre nos sistemas de distribuição de energia elétrica. Capacitores shunt são largamente utilizados nos alimentadores primários dos sistemas de distribuição para compensar potência reativa e conseqüentemente obter melhor perfil de tensão, reduções das perdas de potência e energia, e aumento da capacidade da rede de distribuição em atender carga ativa. A decisão do local ótimo de instalação de bancos de capacitores corresponde a um problema de programação matemática combinatorial. A determinação da influência da modelagem da carga na solução do problema, a inclusão de objetivos técnicos relacionados ao controle de tensão, custos de operação e de manutenção, e perdas de potência e energia, resultando numa nova formulação multi-critério com critérios conflitantes para o problema, e a viabilidade da aplicação de algoritmos genéticos como método de solução dessa nova formulação justificaram o desenvolvimento desta pesquisa. A definição do problema, e o desenvolvimento de modelagens matemáticas podem ser encontrados na primeira parte do trabalho. Na segunda parte apresentam-se os métodos de resolução utilizados nesse trabalho, são eles: heurísticos, e um método meta-heurístico. Um dos métodos heurísticos utiliza fatores de participação reativos da teoria de estabilidade de tensão para resolução do problema. O método meta-heurístico é um algoritmo baseado em algoritmos genéticos que resolve a formulação matemática apresentada anteriormente. Os métodos são testados utilizando-se uma rede real de 70 barras. Efeitos de cargas dependentes da tensão no problema são avaliados
Abstract: It is well known that the major portion of active power losses happen in the electric power distribution feeders. Shunt capacitors are broadly used in the primary feeders to compensate reactive power and consequently to obtain better voltage profile, reductions of power and energy losses, and increase the distribution network capacity in supplying active power demand. The decision of the optimal capacitors banks installation corresponds to a combinatorial mathematical programming problem. The determination of the influence of the load modeling in the solution of the problem, the inclusion of technical objectives relating to voltage control, costs of operation and maintenance, and cost of power and energy losses, resulting in a new multi-criteria formulation with conflicting criteria to the problem, and the viability of the application of genetic algorithms as method of solution of that new formulation justified the development of this research. The definition of the problem and the development of mathematical models can be found in the first part of the work. In the second it is presented the resolution methods, they are: heuristic, and a meta-heuristic method. One of the heuristic methods uses reactive participation factors commonly applied for voltage stability analysis of power systems. The meta-heuristic method is an algorithm based on genetic algorithms that solve the mathematical formulation previously presented. The methods are tested by using a real network of 70 bars. Effects of voltage dependent loads in the problem are quantified
Mestrado
Energia
Mestre em Engenharia Elétrica
Zubo, Rana H. A. "Distribution Network Operation with High Penetration of Renewable Energy Sources. Joint Active/Reactive Power Procurement: A Market-Based Approach for Operation of Distribution Network." Thesis, University of Bradford, 2019. http://hdl.handle.net/10454/18267.
Повний текст джерелаMinistry of Higher Education and Scientific Research - Iraq
The selected author's publications, the published versions of which were attached at the end of the thesis, have been removed due to copyright.
Martin, Dillon Minkoff. "Hydrodynamic Design Optimization and Wave Tank Testing of Self-Reacting Two-Body Wave Energy Converter." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/80298.
Повний текст джерелаMaster of Science
Muller, Heloisa Helena 1965. "Redes neurais artificiais aplicadas a sistemas de potencia." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/262009.
Повний текст джерелаDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
Made available in DSpace on 2018-08-11T05:47:59Z (GMT). No. of bitstreams: 1 Muller_HeloisaHelena_M.pdf: 1272493 bytes, checksum: d78e9e8d9a329ccbf0cc8be6f666af25 (MD5) Previous issue date: 2008
Resumo: A operação de um sistema de energia elétrica pode ser gerenciada remotamente através dos centros de controle utilizando sistemas de gerenciamento de energia (Energy Management Systems-EMS). Nesses centros de controle são realizadas e executadas freqüentemente muitas funções em tempo real e em modo de estudo. Dentre estas funções têm-se: o controle automático da geração, a estimação de estado, análise de topologia e análise estática de segurança entre tantas outras. A base da resolução destas funções é a execução e testes de um grande número de cálculos de fluxos de potência. A estimativa de estado de um sistema de potência pode ser determinada resolvendo as equações de um fluxo de carga, que matematicamente são representadas por um conjunto de equações algébricas não lineares. Este problema é conhecido como fluxo de potência ou fluxo de carga, e o seu objetivo principal é o cálculo das magnitudes das tensões e seus ângulos de fase, e consequentemente dos fluxos de potência nas linhas de transmissão. O objetivo deste estudo é usar redes neurais artificiais (RNA) na: (a) solução do fluxo de carga (FC); (b) solução do FC considerando controle de limites de tensão nas barras PV; (c) inicialização de um FC para sistema mal condicionados; e (d) cálculo de equivalentes externos estáticos para sistemas de energia elétrica. A idéia é que um fluxo de potência baseado em RNA seja mais rápido que o fluxo de potência convencional baseado no método de Newton-Raphson, particularmente nos casos envolvendo aplicações em tempo rela e em modo de estudo avançadas de fluxos de potência no EMS
Abstract: The operation of electric power systems can be managed remote and automatically from control centers using energy management systems (EMS). In these control centers many on-line and off-line functions are carried out periodically. Among those functions, we can list: the automatic generation control, state estimation, topological analysis, and static security analysis. These functions are based on the calculation of a large number of power flows. The operating state of power systems may be determined by solving power flow equations that are mathematically represented by a set of non-linear algebraic equations. This problem is known as the load flow or power flow problem and its main objective is the calculation of all bus voltage magnitudes and angles, and consequently the power flows through the transmission lines. The goal of this study is to propose an artificial neural networks (ANN) based methodology for (a) solving the basic load flow, (b) solving basic load flow considering reactive power limits of generation (PV) buses, (c) determining a good quality load flow starting point for ill-conditioned systems, and (d) computing static external equivalent circuits. The proposed ANN based power flow solver is intended to be faster than the conventional power flow problem solvers which use Newton-Raphson method, particularly in those cases involving advanced on-line applications of the power flow problem in the EMS
Mestrado
Energia Eletrica
Mestre em Engenharia Elétrica
Stefopoulos, Georgios Konstantinos. "Quadratic power system modeling and simulation with application to voltage recovery and optimal allocation of VAr support." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29695.
Повний текст джерелаCommittee Chair: Meliopoulos, A. P. Sakis; Committee Member: Deng, Shijie; Committee Member: Divan, Deepakraj; Committee Member: Harley, Ronald; Committee Member: Taylor, David. Part of the SMARTech Electronic Thesis and Dissertation Collection.
Ягуп, Катерина Валеріївна. "Покращання енергетичних показників електротехнічних систем із застосуванням пошукової оптимізації на комп'ютерних моделях". Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/35541.
Повний текст джерелаThesis for a Doctor’s degree in Engineering Science by specialty 05.09.03 – Electrical Engineering Complexes and Systems. – National Technical University "Kharkov Polytechnic Institute", Kharkiv, 2018. The dissertation is devoted to the development and research of optimization methods of power supply systems modes in electrotechnical systems with asymmetric and nonlinear loads in order to increase the energy indices and calculate the parameters of symmetry-compensating devices using mathematical and computer models, and using search engine optimization implemented with the use of modern software of computer mathematics. The necessity and the possibility of using computer tools for solving set tasks are substantiated. The generalized algorithms for implementing search engine optimization using modern software packages are developed. The possibilities of applying different optimization criteria for solving the problems of increasing the energy indices of power supply systems with asymmetric and nonlinear loads are shown. The properties of the search engine optimization system have been found to extrude the inappropriate element of the synthesized device, as well as the possibility of releasing the optimization variables by increasing their amount, which allows us to get ahead of a faster locating of the local minimum and then recalculate the parameters corresponding to the global minimum are shown. The developed method of search optimization using the models of power supply systems has been successfully applied for optimization of regimes and synthesis of symmetry-compensating devices in three-phase three-wire and four-wire systems of power supply. The possibilities of using the optimization tools for Mathcad and Matlab software packages are considered, in particular, using zero-order methods that do not require the calculation of derivatives, such as the deformed polyhedron method and the conjugate gradient method. The algorithm of load equivalence is proposed, with the help of which the symmetrical and asymmetric parts of the load are allocated. After this, the parameters of the balancing device are determined with sufficient accuracy by means of the Steinmetz and Kennely formulas. The method of currents direct symmetric component rotation with the preservation of symmetry and the mode of full reactive power compensation is proposed. For four-wire systems, the use of a generalized reactive element in a symmetry-compensating device is proposed, which accelerates the process of achieving the optimal solution. The method of determining the optimal mode based on the decomposition of the power supply system, which improves the convergence of the solution processes, is developed. Systems of power supply containing inductively coupled elements are considered. The calculation of the symmetry-compensating device of the traction system of the alternating current railway power supply is considered. A four-wire system with a neutralizer was studied, with the help of search engine optimization the parameters of the symmetry-compensating device were determined which allows to balance and counterbalance such a system. The possibilities of optimization of the regime in the power system of asynchronous motors, including the asymmetry of the supply network, are shown. Compensation of reactive power allows here to reduce the consumed currents and increase the efficiency of the system. To find the optimal modes of systems with an arc discharge, visual models have been developed that are adapted for use with the SimPowerSystem library elements. With the help of these models, the possibilities of increasing the power indices of arc discharge power supply systems, including high-pressure lighting devices, are investigated. It was shown that the optimization of the power factor alone, calculated with the help of the pro-posed methods, leads to decrease in the current consumed by the fundamental harmonic, which substantially reduces the losses in the transmission lines. For a thyristor compensator with single-stage switching, the advantage of symmetric control is proven, which greatly improves the spectrum of harmonics of supply currents. The use of the search optimization method to increase the power factor is shown without the use of traditional rather complicated control systems by power active filters. Comparison signals are used as control signals, synchronized with the phase voltages of the supply system. The amplitudes of these signals are accepted as optimization variables, and the optimization criterion is determined by the balance of active power in the system, which is characterized by the stabilization of the periodic voltage on the storage capacitor of the power active filter. The problems of synthesis of symmetric-compensating devices for several asymmet-rical loads in parallel and cascade connection are considered. The task is to determine the parameters of the symmetric-compensating devices for each of the loads separately, and the contribution to the creation of asymmetry and the generation of reactive power of each connected load must be taken into account. This problem is solved by the method of search optimization, and it is shown that, in forming the objective function, currents in the feeders, supplying energy from the point of connection of the load to the network to the common point of connection of the load and the symmetric-compensating device. It is effective to use the developed decomposition method, which makes it possible to simplify and accelerate the determination of the optimal regime of the system under study, taking into account the contribution of each load to the reduction of the energy parameters of the system as a whole. The case is also analyzed when two loads consisting of both unbalanced linear and nonlinear loads are simultaneously connected to the network. Optimization of the regime with increasing power factor is achieved by using a parallel power active filter with control over the proposed optimization algorithm. Methods and algorithms of search optimization developed for the purposes of increasing the energy indicators of power supply systems with asymmetric and nonlinear consumers developed and presented in the thesis work are characterized by high accuracy, the maximum possible use of computer technology, low computer time and the possibility of complete automation of design and research procedures in solving theoretical and practical tasks related to increasing energy performance and quality of electrical energy in power supply systems.
Ягуп, Катерина Валеріївна. "Покращання енергетичних показників електротехнічних систем із застосуванням пошукової оптимізації на комп'ютерних моделях". Thesis, Харківський національний університет міського господарства ім. О. М. Бекетова, 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/35543.
Повний текст джерелаThesis for a Doctor’s degree in Engineering Science by specialty 05.09.03 – Electrical Engineering Complexes and Systems. – National Technical University "Kharkov Polytechnic Institute", Kharkiv, 2018. The dissertation is devoted to the development and research of optimization methods of power supply systems modes in electrotechnical systems with asymmetric and nonlinear loads in order to increase the energy indices and calculate the parameters of symmetry-compensating devices using mathematical and computer models, and using search engine optimization implemented with the use of modern software of computer mathematics. The necessity and the possibility of using computer tools for solving set tasks are substantiated. The generalized algorithms for implementing search engine optimization using modern software packages are developed. The possibilities of applying different optimization criteria for solving the problems of increasing the energy indices of power supply systems with asymmetric and nonlinear loads are shown. The properties of the search engine optimization system have been found to extrude the inappropriate element of the synthesized device, as well as the possibility of releasing the optimization variables by increasing their amount, which allows us to get ahead of a faster locating of the local minimum and then recalculate the parameters corresponding to the global minimum are shown. The developed method of search optimization using the models of power supply systems has been successfully applied for optimization of regimes and synthesis of symmetry-compensating devices in three-phase three-wire and four-wire systems of power supply. The possibilities of using the optimization tools for Mathcad and Matlab software packages are considered, in particular, using zero-order methods that do not require the calculation of derivatives, such as the deformed polyhedron method and the conjugate gradient method. The algorithm of load equivalence is proposed, with the help of which the symmetrical and asymmetric parts of the load are allocated. After this, the parameters of the balancing device are determined with sufficient accuracy by means of the Steinmetz and Kennely formulas. The method of currents direct symmetric component rotation with the preservation of symmetry and the mode of full reactive power compensation is proposed. For four-wire systems, the use of a generalized reactive element in a symmetry-compensating device is proposed, which accelerates the process of achieving the optimal solution. The method of determining the optimal mode based on the decomposition of the power supply system, which improves the convergence of the solution processes, is developed. Systems of power supply containing inductively coupled elements are considered. The calculation of the symmetry-compensating device of the traction system of the alternating current railway power supply is considered. A four-wire system with a neutralizer was studied, with the help of search engine optimization the parameters of the symmetry-compensating device were determined which allows to balance and counterbalance such a system. The possibilities of optimization of the regime in the power system of asynchronous motors, including the asymmetry of the supply network, are shown. Compensation of reactive power allows here to reduce the consumed currents and increase the efficiency of the system. To find the optimal modes of systems with an arc discharge, visual models have been developed that are adapted for use with the SimPowerSystem library elements. With the help of these models, the possibilities of increasing the power indices of arc discharge power supply systems, including high-pressure lighting devices, are investigated. It was shown that the optimization of the power factor alone, calculated with the help of the pro-posed methods, leads to decrease in the current consumed by the fundamental harmonic, which substantially reduces the losses in the transmission lines. For a thyristor compensator with single-stage switching, the advantage of symmetric control is proven, which greatly improves the spectrum of harmonics of supply currents. The use of the search optimization method to increase the power factor is shown without the use of traditional rather complicated control systems by power active filters. Comparison signals are used as control signals, synchronized with the phase voltages of the supply system. The amplitudes of these signals are accepted as optimization variables, and the optimization criterion is determined by the balance of active power in the system, which is characterized by the stabilization of the periodic voltage on the storage capacitor of the power active filter. The problems of synthesis of symmetric-compensating devices for several asymmet-rical loads in parallel and cascade connection are considered. The task is to determine the parameters of the symmetric-compensating devices for each of the loads separately, and the contribution to the creation of asymmetry and the generation of reactive power of each connected load must be taken into account. This problem is solved by the method of search optimization, and it is shown that, in forming the objective function, currents in the feeders, supplying energy from the point of connection of the load to the network to the common point of connection of the load and the symmetric-compensating device. It is effective to use the developed decomposition method, which makes it possible to simplify and accelerate the determination of the optimal regime of the system under study, taking into account the contribution of each load to the reduction of the energy parameters of the system as a whole. The case is also analyzed when two loads consisting of both unbalanced linear and nonlinear loads are simultaneously connected to the network. Optimization of the regime with increasing power factor is achieved by using a parallel power active filter with control over the proposed optimization algorithm. Methods and algorithms of search optimization developed for the purposes of increasing the energy indicators of power supply systems with asymmetric and nonlinear consumers developed and presented in the thesis work are characterized by high accuracy, the maximum possible use of computer technology, low computer time and the possibility of complete automation of design and research procedures in solving theoretical and practical tasks related to increasing energy performance and quality of electrical energy in power supply systems.
Pereira, Marcos. "Um estudo para alocação ótima de potência reativa utilizando o método dos multiplicadores de Lagrange." Universidade de São Paulo, 1995. http://www.teses.usp.br/teses/disponiveis/18/18133/tde-22012018-114224/.
Повний текст джерелаThis work presents a methodology for the allocation of reactive sources in electrical power systems. The methodology is based on Lagrange\'s multiplier that points out the sensibility between the objective function - transmission active power loss and the constraints reactive power injections. The Lagrange\'s multipliers are obtained by imposing the conditions of stationarity at Augmented Lagrangeana function, that is connected to the Optimal Load Flow problem. The methodology is compared with the Simplex method and the original system. Tests were canied out with AEP14 and AEP30 systems, that showed the efficiency of the methodology.
CHRISTO, ELIANE DA SILVA. "REACTIVE POWER FORECASTING." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7622@1.
Повний текст джерелаNo novo modelo do Setor Elétrico é essencial desenvolver novas técnicas que estimem valores futuros, a curto e longo-prazos, das potências ativa e reativa. Com base nisso, este trabalho tem por objetivo apresentar uma nova técnica de previsão horária de potência reativa a curto-prazo, por subestação, baseada na linearidade existente entre as potências ativa e reativa. O modelo proposto, denominado de Modelo Híbrido de Previsão de Reativo, é dividido em duas etapas: A primeira etapa é feita uma classificação dos dados através de uma rede neural não supervisionada Mapas Auto-Organizáveis de Kohonen (SOM); A segunda etapa, utiliza-se um modelo de defasagem distribuída auto-regressivo (ADL) com estimação de Mínimos Quadrados Reponderados Iterativamente (IRLS) acoplado a uma correção para autocorrelação serial dos resíduos - Método Iterativo de Cochrane-Orcutt. Este Modelo Híbrido tem como variável dependente a potência reativa, e como variáveis explicativas dados horários de potência ativa e reativa no instante atual e defasadas no tempo. A previsão de potência reativa a curto-prazo é dividida em in sample e em out of sample. A previsão out of sample é aplicada a períodos horários em até um mês à frente. O modelo proposto é aplicado aos dados de uma concessionária específica de Energia Elétrica e os resultados são comparados a um modelo de Regressão Dinâmica convencional e a um modelo de Redes Neurais Artificiais Feedforward de Múltiplas camadas (MLP) com um algoritmo de retropropagação do erro.
The forecasting of reactive and active power is an important tool in the monitoring of an Electrical Energy System. The main purpose of the present work is the development of a new short-term reactive power hourly forecast technique, which can be used at utility or substations levels. The proposed model, named A Hybrid Model for Reactive Forecasting, is divided in two stages. In the first stage, the active and reactive power data are classified by an unsupervised neural network - the Self-Organized Maps of Kohonen (SOM). In the second stage, a Autoregressive Distributed Lags Model (ADL) is used with its parameters estimated by an Iteratively Reweighted Least Square (IRLS). It also includes a correction lag structure for serial autocorrelation of the residuals as used in the Cochrane-Orcutt formulation. The short term reactive power forecasting is divided in in sample and out of sample. The out of sample forecast is applied to hourly periods until one month ahead. The proposed model is applied to real data of one substation and the results are compared with two other approaches, a conventional Dynamic Regression and a Feedforward Multi-layer Perceptron (MLP) Artificial Neural Network model.
Canoas, Ana Carolina Garcia. "Logica nebulosa e tecnica de otimização particle swarm aplicados ao controle de tensão e de potencia reativa." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260661.
Повний текст джерелаTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
Made available in DSpace on 2018-08-11T08:34:49Z (GMT). No. of bitstreams: 1 Canoas_AnaCarolinaGarcia_D.pdf: 790052 bytes, checksum: bdc65cd1e622b5ffa74f95691e03751e (MD5) Previous issue date: 2008
Resumo: Devido ao crescente aumento da demanda de energia elétrica e ao retardo de investimento na expansão dos sistemas e energia elétrica (SEE), a operação destes sistemas está cada vez mais próxima de seus limites operacionais, contribuindo para maior complexidade dos SEE. Neste sentido, para satisfazer as rígidas condições de operação, um gerenciamento do perfil de tensão e fluxo de potência tem se tornado cada vez mais importante para as concessionárias, de modo a aumentar a segurança operacional dos sistemas e otimizar o uso de fontes de potência reativa, visando suprir aos consumidores energia dentro de determinados padrões de qualidade e confiabilidade. o objetivo principal desta pesquisa é o desenvolvimento de metodologias com o objetivo de monitorar o perfil de tensão, mantendo-o dentro dos limites operativos, visando não perder a qualidade de fornecimento de energia elétrica. O primeiro método trata-se de uma ferramenta de auxílio à tomada de decisão dos operadores nos centros de controle, baseada em um conjunto de regras nebulosas, o qual é a base do sistema de inferência fuzzy (ou nebulosa) que por sua vez se fundamenta na teoria de conjuntos nebulosos. Considerando que o problema de controle de tensão e de potência reativa apresenta características de natureza não-linear e que envolve variáveis de controle contínuas e discretas, foi desenvolvido um segundo método, o qual utiliza lógica nebulosa em conjunto com a técnica de otimização particle swarm. Este método mostra a possibilidade de incorporar lógica nebulosa em algoritmos baseados em busca, possibilitando a redução das perdas do sistema, satisfazendo as restrições de operação, e garantindo que o perfil de tensão mantenha-se dentro dos limites operativos com uma melhor utilização das fontes de potência reativa
Abstract: Due to the growing electrical power demand and the lag of transmission system infrastruc ture, the operation of transmission systems approaches to its limits and increases the complexity of the system operation. ln this context, in order to satisfy the more rigid operating conditions, managing voltage profile and power flow in a more effective way becomes very important to the power companies that have the aim of enhancing the operating conditions and optimiz ing reactive power sources to provide the consumers with an adequate quality and reliability standards. The main objective of this research work is the development of methodologies for monitoring the volt age profile in order to keep it within operating limits and preserving the quality of the energy being served. The first method consists of a tool for helping decision making by system operators in control centres. This method is based on a set of fuzzy rules, which are the base of a fuzzy inference system. Considering that the voltage and reactive power control present nonlinear characteristics and mixed continuous and discrete variables, a hybrid meta-heuristic method based on fuzzy system and particle swarm optimization has been developed. The fuzzy system has been incorporated into swarm intelligence to provide operational point that allows reduction of system losses while satisfies the operationallimits, volt age constraints and the best utilisation of reactive power
Doutorado
Energia Eletrica
Doutor em Engenharia Elétrica
Beordo, Lucas. "Planejamento da operação de controles de reativo e tensão considerando restrições de estabilidade de tensão." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18154/tde-06112018-073351/.
Повний текст джерелаThe operation of an Electric Power System is complex, mainly due to the great number of restrictions imposed on the variables and the magnitudes of the system, whether of a physical nature or a requirement for the quality and continuity of the electricity supply delivered to consumers. The management of voltage and the power flow, active and reactive, is crucial for the safely operation of the Electric Power System, with quality and low cost. The management of the voltages and powers is performed through the adjustments of the Electric Power System control devices, however, determine the states of the Electric Power System controlled devices is not a trivial task. The determination of the states of the controlled devices becomes even more difficult, since, to guarantee the supply of electricity, continuous and of quality, several scenarios (contingencies) must be analyzed and the control actions imposed on the Electric Power System must satisfy all the Electric Power System operational requirements for all scenarios. Several blackouts occurred due to the voltage instability in the Electric Power System and when they are in high load conditions, the problem becomes even more evident. This work proposes a computational tool for the planning of the actions of reactive and voltage controls in Electric Power Systems that maintain, throughout the day, the variables and the magnitudes of the system within the feasible region of operation and, also, guarantee voltage stability margin sufficient to avoid the voltage collapse. To develop this tool, the planning problem of voltage control and reactive control was formulated as an optimization problem, where, in this problem, two objectives and methodologies were used. In the first one, it was tried to determine the controlled devices states that minimize the transmission lines losses at a time and power interval, and, in the second, to determine the controlled devices states that maintain the variables and quantities of the system within feasible region during the largest power interval, thus the control actions changes in the Electric Power Systems are minimize. Was also proposed, in this work, a methodology for identify the critical contingencies of Electric Power Systems. The results obtained through problem resolutions indicated that the proposed formulations are able to determine the controlled devices states of the system throughout the day, so that there were no violations of the system\'s operational constraints while there were control measures, assessment the base case and a list of contingencies. In addition, the base case and contingencies voltage stability margins have always been maintained above the specified safety value. The results also showed that the methodology for the identification of the critical contingency is able to identify the contingency that limits the system load growth, in order to ensure that the Electric Power Systems is operating with the lowest risk to voltage instability, maintaining the system variables and magnitudes within the feasible region for the largest number of scenarios.
Salamat, Sharif Saied. "Optimal reactive power flow problem." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0013/NQ38355.pdf.
Повний текст джерелаChakrabarti, Bhujanga B. "Reactive power management and pricing." Thesis, University of Canterbury. Management, 2003. http://hdl.handle.net/10092/4495.
Повний текст джерелаHawkins, Nigel Trevor. "On-line reactive power management in electric power systems." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363434.
Повний текст джерелаChebbo, Ahmad Mustapha. "Security constrained reactive power dispatch in electrical power systems." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/6580/.
Повний текст джерелаAbbott, Stephen. "Reactive power dispatch using distributed generation." Thesis, Queen's University Belfast, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602402.
Повний текст джерелаBARAN, IVO SERGIO. "ECONOMIC VALUE OF REACTIVE POWER DEVICES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=3197@1.
Повний текст джерелаNo novo modelo para o setor elétrico brasileiro a operação do sistema é de responsabilidade do Operador Independente do Sistema enquanto que a propriedade do equipamento e os gastos com a sua manutenção são de responsabilidade do agente prestador do serviço ancilar.Desta forma, o lucro do agente prestador do serviço ancilar de potência reativa será função do custo deste serviço uma vez que a sua remuneração é previamente definida pelo agente regulador. Dentro desta ótica os riscos operacionais dos equipamentos de compensação de potência reativa, se não forem convenientemente mitigados,poderão aumentar os gastos com a manutenção e o pagamento de multa pela indisponibilidade do equipamento.Riscos operacionais são situações de sistema que estão fora da responsabilidade do agente mas que poderão reduzir o seu faturamento.Esta dissertação descreve os riscos operacionais e faz algumas sugestões para proteger o agente da redução do seu faturamento.
In the new brazilian deregulated electrical network, system operation is under Independent System Operator responsibility while the ancillary service agent is the owner of the reactive power equipment and, as a consequence, is responsible for its maintenance costs. In the new model, the profit of the agent is a function of the maintenance costs because his payment is previously defined by the authorities. The operational risks of the reactive power equipments, if not conveniently mitigated, may increase the maintenance frequency and may also result in the payment of a fee due to the equipment unavailability.Operational risks are events in the electrical transmission system that are not under the responsibility of the agent but may reduce his profits. This report describes these operational risks and makes some suggestions to protect the agent against the reduction in his profits.
NOGUEIRA, GISELA APARECIDA SILVA. "COSTS ALLOCATION OF REACTIVE POWER DEVICES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=3511@1.
Повний текст джерелаNo atual modelo econômico do setor elétrico, é necessário identificar os agentes beneficiados pelos serviços ancilares à transmissão de potência de forma a alocar adequadamente os custos de investimento, de operação e manutenção do equipamento necessário para a prestação do serviço. Entre os serviços ancilares, destaca-se o suporte de potência reativa para a regulação de tensão. Este trabalho apresenta um método baseado nos multiplicadores de Lagrange de um problema de otimização associado ao cálculo das medidas corretivas necessárias para lidar com níveis de tensão inadequados. Dois critérios de otimização são definidos: mínimo corte de carga e mínima alocação de potência reativa. Os multiplicadores de Lagrange definem a responsabilidade de cada barra quando ocorrem violações de tensão no sistema. O método permite não só identificar as barras beneficiadas pelo equipamento de compensação de potência reativa como também alocar os custos entre elas. É priorizada a confiabilidade do sistema, analisando as contingências possíveis e considerando suas respectivas probabilidades de ocorrência. O programa computacional NH2, desenvolvido pelo CEPEL, é a ferramenta básica para o desenvolvimento deste trabalho. O método é aplicado, a título de ilustração, ao sistema IEEE - RTS de 24 barras e ao sistema da Área Rio. Os resultados obtidos são comparados com um método já existente, que define fatores de alocação de custos medindo os benefícios às barras devido ao suporte de potência reativa. Esta comparação, benefício x responsabilidade, e a própria teoria dos dois métodos, mostram que o método proposto identifica mais adequadamente as barras e os respectivos fatores para a repartição dos custos.
It is important to identify the agents that take advantage of the ancillary services for system operation in the nowadays electricity market. The actual economic design requires that the costs of investment, operation and maintenance of the necessary equipment should be properly allocated between these agents. Among the ancillary services, the reactive power support for voltage regulation is quite important. It is presented a method that identifies the buses that take advantage of the reactive power equipment and allocates the costs between each one of them. The power system reliability is taken into account. The analysis considers possible contingencies and their respective probability of occurrence. The computer program NH2, developed by CEPEL, is the main tool for the development of this work. The method is based on the Lagrangian multipliers of an optimal power flow problem (OPF) associated to corrective measures necessary to deal with voltage violations. Two different objective functions are used: minimum load shedding and minimum reactive power injection. The Lagrangian multipliers define the responsibility of each bus when system voltage violations occur. For the purpose of illustration, the method is applied on the 24 bus IEEE Reliability Test System and on Área Rio system. Results are compared with those produced by other existing method that defines cost allocation factors measuring the benefit due the reactive support. This comparison, benefit x responsibility, and the theory used by both methods, show that the proposed method identifies more appropriately the buses and the corresponding factors to allocate the costs.
Hasan, MD Shakib. "Reactive Power Control for Voltage Management." Thesis, Uppsala universitet, Elektricitetslära, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-325271.
Повний текст джерелаSouza, Rafael Ramos de [UNESP]. "Um método primal-dual de pontos interiores/exteriores com estratégias de teste quadrático e determinação de direções de busca combinadas no problema de fluxo de potência ótimo reativo." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/142853.
Повний текст джерелаApproved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-11T12:16:39Z (GMT) No. of bitstreams: 1 souza_rr_me_bauru.pdf: 1452852 bytes, checksum: ae6aa21d2282113ac3abaade8414218e (MD5)
Made available in DSpace on 2016-08-11T12:16:39Z (GMT). No. of bitstreams: 1 souza_rr_me_bauru.pdf: 1452852 bytes, checksum: ae6aa21d2282113ac3abaade8414218e (MD5) Previous issue date: 2016-06-10
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O problema de Fluxo de Potência Ótimo tem por objetivo a otimização de um critério de desempenho elétrico sujeito ao atendimento das demandas de potência ativa e reativa em cada barra e de restrições técnico-operacionais dos sistemas de geração e transmissão. É um problema de otimização, não-linear, não-convexo e de grande porte. Neste trabalho é explorado o problema de Fluxo de Potência Ótimo Reativo com o objetivo de minimizar as perdas de potência ativa na transmissão e para resolvê-lo é proposto um método primal-dual de pontos interiores/exteriores barreira logarítmica modificada com estratégias de teste quadrático e determinação de direções de busca combinadas. O teste quadrático é proposto como alternativa ao procedimento de Cholesky na verificação da positividade da matriz hessiana do problema, que, se definida positiva, garante direções de descida para o método. As novas direções de busca são determinadas através de combinações das direções dos procedimentos previsor e corretor, determinadas através da análise das condições de complementaridade das variáveis primais e duais do problema. O método proposto foi implementado em Matlab e aplicado aos sistemas elétricos 9 e 39 barras e aos sistemas IEEE 14, 30, 57 e 118 barras. O desempenho do método com as estratégias propostas é avaliado em termos do número de iterações e do tempo computacional. Os resultados são promissores e permitem a aplicação do presente método, com as estratégias propostas, para resolver o problema de Fluxo de Potência Ótimo Reativo com maior dimensão do que os sistemas testados.
The reactive optimal power flow problem is concerned with the optimization of a specific criterion associated with the transmission system while enforcing the power balance in each transmission bus, as well as operational and physical constraints associated with generation and transmission systems. It is a nonlinear, non-convex and large optimization problem. In this work we consider the active losses minimization in the transmission system as a criterion for the optimal power flow problem. The solution of the problem is investigated by proposing a modified log-barrier primal-dual interior/exterior point method with a quadratic test strategy and new search direction procedures. The quadratic test is proposed as an alternative strategy to the Cholesky procedure for calculating the positivity of the Hessian matrix of the problem.The new search directions investigated in the paper are determined by combining the search directions calculated in the predictor and corrector steps, respectively, and also by using information associated with the complementarity conditions. The method proposed is implemented in Matlab and applied to solving the reactive optimal power flow problem for 9 and 39-bus systems, as well as for the IEEE 14, 30, 57 and 118-bus test systems. The performance of the method with the proposed strategies for search directions is evaluated in terms of the number of iterations and computational times. The results are promising and allow the application of the present method with the proposed search strategies for solving problems of larger dimensions.
Li, Jinbo 1961. "A study of reactive power dispatch under restructured power systems /." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80120.
Повний текст джерелаThe first follows the two-step approach adopted by some electricity markets where first, the generators' real powers are dispatched in the energy market, followed by the dispatching of the generator reactive power support services in the ancillary services market.
Once the generators' real power has been dispatched in the energy market, the generators' reactive power is dispatched according to the minimization of a combination of multiple objectives: network MW loss cost, generator opportunity cost, and generator MW shift cost. The MW loss cost is represented as a function of bus voltage magnitudes and angles as well as the nodal prices in $/MWh found in the first step. Opportunity cost is represented as a function of the generator reactive powers, whose cost parameters are derived in terms of the MW dispatch, the MW nodal prices and the generators' capabilities. The generator shift cost is represented as a function of the generator real powers and the MW shift weighting factor. As these three objectives may conflict, compromises are needed to arrive at an optimum solution.
The second reactive power dispatch approach unifies real and reactive power dispatch by minimizing both MW and MVAr generation costs while enforcing the MW and MVAr/voltage constraints simultaneously. This unified dispatch avoids a disadvantage of the two-step MVAr dispatch, that is, that the MW price signal determined in the energy market may be distorted by the subsequent MVAr dispatch in the ancillary services market.
Several numerical examples under different conditions are presented to examine and compare the effectiveness of these two methods.
SILVA, FRANCISCO CARLOS SANTANNA DA. "ACTUAL REACTIVE POWER CAPABILITY EVALUATION IN AN ELECTRICAL POWER PLANT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2472@1.
Повний текст джерелаAs curvas de capacidade de geração de potência reativa fornecidas pelos fabricantes são elaboradas em função dos parâmetros de projeto do gerador, e geralmente não consideram as condições de operação da planta e do sistema como fatores limitantes. É sabido que as condições de operação da planta, tais como tensões nominais do terminal do gerador e das barras auxiliares, valores limites dos reguladores de tensão, potência máxima da turbina e dispositivos de limitação e proteção de sub e sobreexcitação podem ser fatores limitantes da capacidade de geração e absorção de potência reativa. Neste trabalho foi elaborado um método e desenvolvida uma ferramenta computacional para identificar a curva de capacidade real de geração de potência reativa para qualquer ponto de operação. Este trabalho pode ser estendido para qualquer gerador, conhecidas as características da usina. Nos estudos de caso apresentados pôde-se verificar que é possível ampliar a capacidade de geração reativa da usina apenas conhecendo seus reais limites, não necessitando portanto, de grandes investimentos para o aumento dessa capacidade.
They show that different generator loads produce greater heating in different parts of generator. A method is described and a software is presented to evaluate the actual reactive power capability curve considering the operating condition.This paper shows that it is possible to enlarge the reactive power capability only by knowing the actual capability limitations, without raising costs and keeping operation safe.It is important to the generator agent to know its capabilities if it is desidered to provide reactive support as an ancillary service in the new competitive environment.
Giessler, Sabine. "Synthesis and Dynamic Optimization of Reactive Distillation Processes." Kyoto University, 2000. http://hdl.handle.net/2433/180939.
Повний текст джерелаHoltsmark, Nathalie Marie-Anna. "Reactive Power Compensation using a Matrix Converter." Thesis, Norwegian University of Science and Technology, Department of Electrical Power Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10040.
Повний текст джерелаThis Master's thesis investigates a new application for the matrix converter: Shunt reactive power compensation. The suggested Matrix Converter-based Reactive power Compensation (MCRC) device is composed of a matrix converter, which input is connected to the grid and an electric machine at the output of the converter. The reactive power flowing in or out of the grid can be regulated with the matrix converter by controlling the magnitude and/or phase angle of the current at the input of the converter. The matrix converter has no bulky DC link capacitor like traditional AC-DC-AC converters. The thought electric machine is a Permanent Magnet (PM) synchronous machine which is compact as well, yielding an overall compact device. The main focus of the thesis is to evaluate the reactive power range that the MCRC device can offer. The reactive power range depends mainly on the modulation of the matrix converter. Two different modulation techniques are studied: the indirect virtual space vector modulation and the three-vector-scheme. The indirect space vector modulation can provide or draw reactive power at the input of the matrix converter as long as there is an active power flow through the converter that is different from zero. For pure reactive power compensation the indirect space vector modulation cannot be used and the three-vector-scheme must be used instead. Both modulation techniques are presented in details as well as their reactive power compensation range. To verify the reactive power capabilities of the device, three different simulation models are built in MATLAB Simulink. The first simulation model represents the MCRC device with the matrix converter modulated with the indirect space vector modulation. The second model represents also the MCRC device with the matrix converter modulated with the three-vector-scheme. In both model the PM machine is represented by a simple equivalent circuit. Simulations done with both models show a good accordance between the theoretical analysis of the device and the experimental results. The last simulation model features a simplified version of the MCRC system connected to a grid where a symmetrical fault occurs. The MCRC proves to be efficient in re-establishing the voltage to its pre-fault value.
Roteta, Alex. "Reactive-power allocation under competitive bilateral transactions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0018/MQ55027.pdf.
Повний текст джерелаLiu, Haifeng. "Planning reactive power control for transmission enhancement." [Ames, Iowa : Iowa State University], 2007.
Знайти повний текст джерелаPhichaisawat, Sotdhipong. "Reactive power management under voltage security constraints." Thesis, Brunel University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249948.
Повний текст джерелаVIEIRA, MARCO AURELIO MOURA. "ACQUISITION COST ALLOCATION OF REACTIVE POWER SOURCES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2001. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=1967@1.
Повний текст джерелаEste trabalho apresenta três métodos para a identificação dos usuários da rede de transmissão que são beneficiados por novas ou já existentes fontes de potência reativa e, em conseqüência, a repartição do custo de capital entre eles. A metodologia para se obter os fatores de alocação de custos, aplicados aos agentes beneficiados, utiliza a análise de um conjunto de contingências de transmissão com suas respectivas probabilidades de ocorrência. Cada um dos métodos propostos utiliza um diferente critério para se medir os benefícios decorrentes da presença de equipamentos de suporte de potência reativa. Os critérios mencionados são os desvios de tensão, os cortes de carga e as injeções de potência reativa, bastante utilizados em estudos de planejamento da operação e da expansão, assim como em análise de confiabilidade de sistemas de potência. A aplicação dos métodos é ilustrada através de estudos de casos com dois sistemas, um sistema simplificado de 5 barras e o IEEE-Reliability Test System (24 barras), no qual um horizonte de três anos é considerado para se fazer a remuneração do equipamento de compensação reativa.
This report presents three methods to identify the transmission consumers in power systems that take advantage of new or existent reactive power sources and, consequently, to allocate its acquisition costs among these consumers. The methodology to obtain the allocation factors, applied to each of the agents, takes into account the analysis of a transmission outages set with their respective probabilities. Each one of the proposed methods uses a different criterion to measure the benefit due to the reactive support provided by such equipments. The mentioned criteria are: voltage deviation, load shedding and reactive power injection. All these methodologies are very used in operational and expansion planning studies, as well as power systems reliability analysis. The application of the methods is shown in case studies with two systems, being the first a 5 bus simplified system and the other, the IEEE-Reliability Test System (24 buses), in which a three years horizon is considered for the reactive power compensation equipment remuneration.
Este trabajo presenta tres métodos para la identificación de los usuários de la red de transmisión que se benefician con las fuentes (nuevas o existenten) de potencia reactiva y, en consecuencia, la repartición del costo de capital entre eles. Hasta aqui, lla metodología para obtener los factores de alocación de costos, aplicados a los agentes beneficiados, utiliza el análisis de un conjunto de contingencias de transmisión con sus respectivas probabilidades de ocurrencia. Cada uno de los métodos propuestos utiliza un critério diferente para medir los beneficios decorrentes de la presencia de equipamentos de soporte de potencia reactiva. Los critérios mencionados son los desvíos de tensión, los cortes de carga y las inyecciones de potencia reactiva, bastante utilizados en estudios de planificación de operación y expansión, así como en análisis de confiabilidad de sistemas de potencia. La aplicación de los métodos se ilustrada a través de estudios de casos con dos sistemas, un sistema simplificado de 5 barras y el IEE Reliability Test Systiene (24 barras), en el cual se considera un horizonte de tres años para realizar la remuneración del equipo de compensación reactiva.
Eiriksson, Eysteinn. "Distribution grid capacity for reactive power support." Thesis, KTH, Elkraftteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-221829.
Повний текст джерелаDet moderna kraftsystemet förandras snabbara än vad som hade förväntats för 20 årsedan. Fler och fler konventionella kraftverk kommer att stängas till fördel för distributionsgenering.Detta händer nu med trenden att introducera förnybara energikällor tillkraftsystemet.Nätverket utformades för att överföra kraft från generatorer som är anslutna till högspänningsnätetmot konsumenter anslutna till lågspänningsnätet. Med ändrad kraftblandningkommer strömflödena i systemet att förändras vilket resulterar i eventuella nätproblem.Ett av huvudproblemen är att hålla spänningen inom operativa gränser för systemet.När generationen överstiger förbrukningen i ett distributionsnät, kommer strömmen attströmma från lågspänningsnätet till högspänningsnätet vilket kommer att leda till attspänningen stiger i lågspänningsnätet. Reaktivt kraftstöd från distributionsgenering kanvara en värdefull resurs för att mildra problemet. Reaktiv effekt är nödvändig för att drivaelsystemet. Huvudkällan för reaktiv kraft är synkrona generatorer. Om den här källanstängs av måste den reaktiva effekten komma från en annan källa.Denna avhandling undersöker om distributionsgenering skulle kunna användas för attstödja reaktiv kraft till högspänningsöverföringsnätet för att styra spänningen. För dettaändamål studeras ett distributionssystem som ligger nära Worms, Tyskland. Detta distributionssystembestår av två MV-matare med med mycket distributionsgenerering, främstsolceller men även vindturbiner. Förbruknings- och generationsmätningsdata tillhandahöllsav den lokala distributionssystemoperatören. Några reaktiva effektstyrningsmetoderintroduceras och testas på detta system. Av resultaten dras slutsatsen att detär möjligt att tillhandahålla reaktivt kraftstöd från distributionsnät och en spänningsberoendereaktiv effektstyrning kan användas för detta ändamål.
Cabrera, Rios Mauricio. "MULTIPLE CRITERIA OPTIMIZATION STUDIES IN REACTIVE IN-MOLD COATING." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1022105843.
Повний текст джерелаHarnoto, Monica. "Value of distribution-level reactive power for combined heat and power systems." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/126901.
Повний текст джерелаThesis: S.M., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, in conjunction with the Leaders for Global Operations Program at MIT, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 56-59).
As the U.S. electric grid continues to experience an increase in the penetration of distributed energy resources (DER), electric utilities are evaluating new approaches for utilizing DER to help cost-effectively maintain grid resilience and reliability. One such approach is to create a transactive market for DER to provide grid services, which are services required to support reliable grid operation. Though work has been done to understand some of the technical mechanisms of this type of market, gaps still exist in understanding the value and market opportunity of ancillary services at the distribution level. One type of ancillary service - reactive power - is of particular interest because of the theoretic ability to source from existing assets on the distribution network. This paper aims to build understanding of the value of procuring reactive power from one of these assets: Combined Heat and Power (CHP) systems. The value of procuring reactive power from a CHP system will be quantified by 1) characterizing CHP systems' capacity to produce and absorb reactive power, 2) assessing the annual cost of procuring reactive power from CHP systems, and 3) comparing the CHP system technical capability and cost to the utility's conventional solution: capacitor banks. This study finds that, while there are promising scenarios in which CHP systems can technically and economically provide reactive power in a comparable or slightly advantaged manner to capacitor banks, the overall statistics for the 29 CHP systems analyzed in the New York fleet do not conclusively demonstrate an advantage that supports outright replacement of capacitor banks. Further assessment of CHP systems as a complementary source of reactive power and site-specific case studies are recommended to inform the next step in the decision making process for determining whether this path should be pursued as a source of reactive power.
by Monica Harnoto.
M.B.A.
S.M.
M.B.A. Massachusetts Institute of Technology, Sloan School of Management
S.M. Massachusetts Institute of Technology, Department of Civil and Environmental Engineering
Boulanger, Isabelle. "Lillgrund Wind Farm Modelling and Reactive Power Control." Thesis, KTH, Elektriska energisystem, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119256.
Повний текст джерелаRavindran, Vinoth Kumar. "Reactive power control functions for distributed PV sources." Thesis, Wichita State University, 2013. http://hdl.handle.net/10057/6835.
Повний текст джерелаThesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science
Prato, Michael V. "Reactive power compensation using an energy management system." Thesis, Monterey, California: Naval Postgraduate School, 2014. http://hdl.handle.net/10945/43982.
Повний текст джерелаA significant contributor to higher energy costs and reduced energy efficiency is the reactive power demand on the grid. Inductive power demand reduces power factor, increases energy losses during transmission, limits real power supplied to the consumer, and results in higher costs to the consumer. Compensating for a reactive power demand on the grid by providing reactive power support to the power distribution system creates energy efficiency gains and improves cost savings. One method of compensating for reactive power is by incorporating an energy management system (EMS) into the power distribution system. An EMS can monitor reactive power requirements on the grid and provide reactive power support at the point of common coupling (PCC) in the power distribution system in order to increase energy efficiency. The use of an EMS as a current source to achieve a unity power factor at the grid is demonstrated in this thesis. The power factor angle was determined using a zero-crossing detection algorithm. The appropriate amount of compensating reactive current was then injected into the system at the PCC and controlled using closed-loop current control. The process was simulated using Simulink and then validated in the laboratory using the actual EMS hardware.
Alturki, Yasir A. A. "Real and reactive power allocations in electricity market." Thesis, University of Strathclyde, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436830.
Повний текст джерелаAl-Anfaji, Ahmed Suaal Bashar. "The optimization of combined power-power generation cycles." Thesis, University of Hertfordshire, 2015. http://hdl.handle.net/2299/15485.
Повний текст джерелаAbacar, Armando. "Optimization of Maputo Power Plant." Thesis, KTH, Kraft- och värmeteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-124249.
Повний текст джерелаZhang, Wanping. "Power network analysis and optimization." Diss., [La Jolla] : University of California, San Diego, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p3369236.
Повний текст джерелаTitle from first page of PDF file (viewed September 17, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 91-94).
Al, Hamrani Majed M. "Reactive power optimization using adaptive excitation control of synchronous power." Thesis, 2002. http://hdl.handle.net/1957/31548.
Повний текст джерелаGraduation date: 2003
CHIANG, YU-CHUAN, and 江昱銓. "Optimal Reactive Power Dispatch Using Ordinal Optimization Algorithm." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/98yp44.
Повний текст джерела高苑科技大學
電子工程研究所
105
In this paper, we propose an Ordinal Optimization (OO) algorithm for the solution of the Optimal Reactive Power Dispatch (ORPD) problem. The main objective of QRPD is to minimize active power loss and improve the voltage profile of power systems. Our algorithm consists of three stages. This work first constructed a crude but efficient model from a sample space. Then, a scheme with enhanced accuracy based on sensitivity theory was applied to identify the top samples to form the selected subset. Finally, we obtain a good enough solution with smallest objective value. The proposed algorithm is tested on IEEE 118-bus system and results are compared with those of tabu research method and genetic algorithms. Test results demonstrate the efficiency of proposed algorithm in finding the good enough solution within a shortest computing time.
Falahi, Milad. "Dynamic Reactive Power Control of Isolated Power Systems." Thesis, 2012. http://hdl.handle.net/1969.1/148126.
Повний текст джерелаNumbi, Bubele Papy. "Optimization of reactive power flow in a wind farm-connected electric power system." 2012. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000359.
Повний текст джерелаOne of the main issues in the integration of large wind power generation into the electric power networks is the voltage drop at the point of common connection (PCC) and the increase in power losses as well. This work deals with the optimization of the reactive power control in a power system with integration of a wind farm with the aim of minimizing the total active power losses and improving the load voltage profiles