Isolated Single Stage AC-DC Converter Topologies with Regenerative Snubber Circuit for EV Application

Electric vehicle (EV) battery charging application requires power converters with higher efficiency and power density. Soft-switched single stage power converters can be suitable for this application as they require lesser number of active and passive components compared to the conventional two stage converters. This paper presents two isolated single phase single stage AC-DC converter topologies for EV application. These converters operate under zero current switching (ZCS) condition. A regenerative flyback based snubber circuit is also presented to mitigate voltage spikes resulted due to the leakage inductor of the high frequency link transformer. A detailed analysis of converter operation is presented in this paper. Key experimental results are shown to validate the performance of these converters in a 1 kW prototype.