Bancos de capacitores se corrente de Inrush

This work discusses about the effects and methods of control and elimination of the currents transients generated by switching capacitor banks, this currents are called inrush currents. Capacitor banks are widely used to compensate a low power factor generated by the widespread use of inductive loads. Currently many of these banks are automatic and therefore the capacitive cells are connected and disconnected according to the inductive loads on the network. However when connecting a capacitor bank to a bus can generate currents transients generated by electromagnetic transients. Aspects of the network, for example, the existence of a bank already connected to the bus, can influence the intensity of this phenomenon. This paper discusses some characteristics of the capacitors and the network to justify and explain the appearance of these transients and discusses its effects on the network and to other equipment. It is concluded that the main cause of this phenomenon is the voltage difference between the capacitor to be connected to the network and the bus, the results of the study were the bases to discuss the traditional methods to mitigate these currents and therefore its negative effects. Although in this paper is yet developed a method of electronic switching that can greatly reduce these transients

Estudo sobre iluminação e banco de capacitores de uma típica indústria metalúrgica

The use of electricity for obtaining light has been quite an issue currently discussed, either through new technologies that are emerging, the quest for greater efficiency, reduced waste and rational use. This work comprises a lighting design applied to a metallurgical based Brazilian Standard 5413 which mentions levels of luminance for interior and, in the case of this work, for a sandblasting booth. Ways to improve the workplace and luminosity presented before the project and also after its implementation are discussed. Technologies are chosen guided by technical calculations according to the illuminance values they want to reach for the environment studied. All pertinent design features are critically analyzed and discussed, and at the end proposals are presented, relating to each other in a comparative framework, so the best solution is applied in a practical way in the enclosure. Results are also presented concerning the maintenance of a bank of capacitors to correct the power factor for the metals studied company

Análise de conversor multipulso utilizando transformador com culatra intermediária

Pós-graduação em Engenharia Elétrica - FEIS

Alocação ótima de chaves de interconexão nas redes de distribuição de energia elétrica

Pós-graduação em Engenharia Elétrica - FEIS

Desenvolvimento de sistema eletrônico para instrumentar um DPL em ensaio dinâmico de resistência do solo

Pós-graduação em Engenharia Elétrica - FEIS

Avaliação otimizada técnica e econômica do ponto de conexão de geração distribuída em redes de média tensão

Pós-graduação em Engenharia Elétrica - FEIS

Utilização de melaço, manipueira e soro de queijo como substratos para produção de biossurfactante por Bacillus Pumilus e sua aplicação em biorremediação de solo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Volt-VAR multiobjective optimization to peak-load relief and energy efficiency in distribution networks

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

A new family of zero-current-switching PWM converters and a novel HPF-ZCS-PWM boost rectifier

A new family of direct current (DC) to DC converters based on a zero current switching pulse width modulated (ZCS-PWM) soft commutation cell is presented. This ZCS-PWM cell is consists of two transistors, two diodes, two inductors and one capacitor; and provides zero voltage turn-on to the diodes, a zero-current turn-on and a zero-current zero-voltage turn-off to the transistors. In addition, a new commutation cell in a new ZCS-PWM boost rectifier is developed, obtaining a structure with power factor near the unity, high efficiency at wide load range and low total harmonic distortion in the input current.

Compensação ativa paralela baseada na teoria de potência conservativa

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

Estratégia de controle multifuncional para sistemas fotovoltaicos de geração de energia elétrica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Proposta de metodologia para o gerenciamento automático de sistemas fotovoltaicos de geração distribuída

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

Controle flexível para conversores monofásicos conectados a sistemas elétricos distorcidos de baixa tensão

This paper presents a technique to add flexibility in the control of power electronic converters. The power converter can function as an active power filter, as a local power source interface or perform both functions i. e. mitigate current disturbances and inject power into the grid simultaneously, configuring it as a multifunctional device. The main goal is to extract the full capability of the grid connected power electronic converter to achieve maximum benefits. To achieve this goal, the orthogonal current decomposition of the Conservative Power Theory is used. Each orthogonal current component is weighted by means of different compensation factors (k_i), which are set instantaneously and independently, in any percentage by means of the load performance factors (λ_i), providing an online flexibility in relation to compensation objectives. Finally, to validate the effectiveness and performance the proposed approach, simulations and experimental results are presented.

Contribuições para o estudo de atribuição de responsabilidades em circuitos elétricos de baixa tensão

Pós-graduação em Engenharia Elétrica - FEB

Proposta de equipamento de conexão à rede para a utilização da geração de energia solar em consumidores de pequeno e médio porte

Pós-graduação em Engenharia Mecânica - FEG