A influência do controlador gupfc no sistema elétrico de potência visando a estabilidade a pequenas perturbações

Pós-graduação em Engenharia Elétrica - FEIS

Reconfiguração de sistemas de distribuição utilizando metaheurísticas e critérios de confiabilidade

In an ever more competitive environment, power distribution companies must satisfy two conflicting objectives: minimizing investment costs and the satisfaction of reliability targets. The network reconfiguration of a distribution system is a technique that well adapts to this new deregulated environment for it allows improvement of reliability indices only opening and closing switches, without the onus involved in acquiring new equipment. Due to combinatorial explosion problem characteristic, in the solution are employed metaheuristics methods, which converge to optimal or quasi-optimal solutions, but with a high computational effort. As the main objective of this work is to find the best configuration(s) of the distribution system with the best levels of reliability, the objective function used in the metaheuristics is to minimize the LOLC - Loss Of Load Cost, which is associated with both, number and duration of electric power interruptions. Several metaheuristics techniques are tested, and the tabu search has proven to be most appropriate to solve the proposed problem. To characterize computationally the problem of the switches reconfiguring was developed a vector model (with integers) of the representation of the switches, where each normally open switch is associated with a group of normally closed switches. In this model simplifications have been introduced to reduce computational time and restrictions were made to exclude solutions that do not supply energy to any load point of the system. To check violation of the voltage and loading criteria a study of power flow for the ten best solutions is performed. Also for the ten best solutions a reliability evaluation using Monte Carlo sequential simulation is performed, where it is possible to obtain the probability distributions of the indices and thus calculate the risk of paying penalty due to not meeting the goals. Finally, the methodology is applied in a real Brazilian distribution network, and the results are discussed.

Uma investigação do minos e sua aplicação ao problema de fluxo de potência ótimo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Congestion Effects on Regional & System Emission and Consumers Allocated Cost

This paper considers the congestion effects on emission and consumers' allocated cost. In order to consider some environmental and operational effects of congestion, an environmental constrained active-reactive optimal power flow (AROPF) considering capability curve is presented. On outage conditions, the total cost of the system will increase. On the other hand in power systems, the operating cost and system emission have conflicted objectives, then it may be concluded that the outage in the system may lead to a total emission decrease. In this paper the famous Aumann-Shapley method is used as a pricing methodology. Two case studies such as 14-bus and US-bus IEEE test systems are conducted. Results demonstrate that, although the line outage in power systems leads to increase the total cost, the amount of emission depending on the place where the outage occurs can be more than, less than or equal to the normal conditions' emission. Also results show that although from power sellers' standpoint the well-known Aumann-Shapley method is a precise pricing method to cover the incurred cost with an acceptable error that can show the real effect of congestion on consumers' cost, from consumers' standpoint it is not a good method for cost allocation, because some consumers will face with an increase in cost and the others will face with a decrease on their cost.

A influência da temperatura nas impedâncias de sequência de condutores utilizados na rede primária de distribuição

Distribution networks are formed by long lines that carry electricity substations to homes and industries. These lines have associated impedance and depending on operating conditions of the network these impedances may vary. This paper provides a detailed analysis of the effects observed in studies of voltage drop, short circuit and electrical losses, when considered the drivers sequence impedances used in primary distribution network at different temperatures. Therefore, it is initially presented a calculation methodology and details the factors that influence the final values. The methodology presented tackles in a practical way the main factors that directly or indirectly influence the values of the impedances as an emblematic example and will be properly dealt with throughout the paper is the effect of temperature on the values of the sequence impedances. More specifically is dealt with the case of XLPE cables protected, by having a higher maximum operating temperature than the operating temperature of the network. The effects observed in the power flow generated when considering the impedance values at both temperatures were analyzed. The impedance drivers tend to increase with increasing temperature. Thus the impedance of the conductor XLPE protected will tend to be greater for the maximum operating temperature for which the operating temperature of the network, resulting in greater voltage drop and higher electrical losses

Sistema de gerenciamento de energia para controle de carga/descarga entre baterias de lítio e ultracapacitores, envolvendo sistema de tração elétrica com frenagem regenerativa

Pós-graduação em Engenharia Elétrica - FEIS

Efeito da hCG ou deslorelina sobre a hemodinâmica folicular e perfil endogeno de LH em éguas cíclicas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desenvolvimento de um sistema de gerenciamento de energia (EMS - Energy Management System) para a rede elétrica inteligente (Smart Grid)

Pós-graduação em Engenharia Elétrica - FEIS

Modelação de redes de distribuição de energia elétrica com carregamento não linear, incluindo elementos de regulação e compensação

Pós-graduação em Engenharia Elétrica - FEIS

Modelagem da capacidade de transporte de sedimentos em latossolo férrico

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Técnicas de parametrização para o fluxo de carga continuado desenvolvidas a partir da análise das trajetórias de soluções do fluxo de carga

Pós-graduação em Engenharia Elétrica - FEIS

Artificial immune networks Copt-aiNet and Opt-aiNet applied to the reconfiguration problem of radial electrical distribution systems

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Reconfiguração de sistemas de distribuição de energia elétrica utilizando uma metodologia multipartida

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fluxo de potência continuado baseado em equações de injeção de corrente expressas em coordenadas polares

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento de um sistema de proteção e metodologia para localização de faltas em sistemas de distribuição

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)