EV와 NEV 겸용 50kW급 고효율 모듈형 급속충전기 개발

In this paper, a 50-kW high-efficiency modular fast charger for both electric vehicle (EV) and neighborhood electric vehicle (NEV) is proposed. The proposed fast charger consists of five 10-kW modules to achieve fault tolerance, ease of thermal management, and reduce component stress. Three-level topologies for both AC–DC and DC–DC converters are employed to use 600V MOSFET, resulting in ease of component selection and increase in switching frequency. The proposed three-level DC–DC converter with coupled inductor and its hybrid switching method can reduce the circulating current under wide output voltage range. A 50-kW prototype of the proposed fast charger was developed and tested to verify the validity of the proposed concept. Experimental results show that the proposed fast charger achieves a rated efficiency of 95.2% and a THD of less than 3%.