Revista Eletrônica de Potência (Brazilian Journal of Power Electronics)

Palavras Chaves: Controle Hierárquico, fontes ininterruptas de energia, Gerenciamento Térmico, Paralelismo

Resumo

Este trabalho propõe uma estrutura de controle hierárquico que permite realizar a equalização das temperaturas internas dos capacitores de barramento de UPSs conectadas em paralelo. Os capacitores eletrolíticos, usualmente utilizados em barramentos CC, são um dos principais responsáveis por falhas em sistemas de conversão de energia, sendo que a vida útil destes componentes é sensível a elevadas temperaturas de operação. Neste sentido, com o intuito de aumentar a vida útil de sistemas ininterruptos de energia conectados em paralelo, este trabalho propõe a adição de uma malha de controle que, através da medição indireta das temperaturas das UPSs, gerencia a potência ativa que cada UPS deve fornecer, a fim de equalizar as temperaturas dos capacitores. Resultados hardware-in-the-loop são adquiridos considerando duas UPSs monofásicas de 10 kVA conectadas em paralelo e localizadas em ambientes com temperaturas distintas, comprovando o bom desempenho e a viabilidade da proposta.

Title: Hierarchical control structure for parallelism of double conversion UPS with equalization of the DC-link capacitors temperatures

Keywords: Hierarchical Control, Parallelism, Thermal Management, Uninterruptible Power Supplies

Abstract

This paper proposes a hierarchical control structure that allows the thermal equalization among the DC-link capacitors of UPSs connected in parallel. The electrolytic capacitors typically used in DC-links are one of the main causes of failure in electronic equipment and the lifetime of this component is sensitive to high operating temperatures. In this sense, this work proposes the addition of a control loop with the objective to increase the lifetime of uninterruptible power systems. Through the estimation of the UPS’s internal temperatures, the proposed control loop manages the active power that each UPS unit must provide to equalize the DC-link capacitors temperatures. Hardware-in-the-loop results are acquired considering two 10 kVA single-phase UPSs connected in parallel and located in places with different temperatures, proving the good performance and the feasibility of the proposal.

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