Desenvolvimento de um circuito para monitoramento da resistência de isolamento de uma estação de recarga rápida para veículos elétricos

Abstract

In a fast charging station, it is mandatory, by technical standards, the monitoring of insulation resistances, preventing recharges from being carried out when there is danger of electric shock for consumers. This paper presents the development of a circuit that measures the insulation resistance of a fast charging station up to 1000 V and informs the control and supervision system of the charging station if the resistance value is suitable for charging. This circuit issues a warning in two resistance values which depend on the maximum output voltage of the station, following the requirements of the standards covering this subject. This paper presents a synthesis of the standards studied and the commercial models of these circuits, which are known as Insulation Monitoring Device (DSI). Also, a step-by-step circuit design and analysis in the PowerSIM simulation software is demonstrated. Finally, the design of the printed circuit boards of this circuit and its practical implementation are presented, in addition to the necessary tests for validation, which show that the circuit is effective and an extremely cheap solution when compared to models presents on the market.