20kW급 전기자동차 긴급구난 급속충전용 고효율 병렬능동클램프 절연형 DC/DC 컨버터의 설계

초록

With the accelerating domestic and international transition to eco-friendly vehicles, the distribution of electric vehicles (EVs) is increasing. However, the lack of EV charging infrastructure limits market expansion, thus requiring countermeasures. EVs can be easily charged at charging facilities for short-distance driving. Yet an emergency rescue rapid charging system is required to recharge the battery during long-distance driving or when the battery runs out. This system consists of a generator, a rectifier, an isolated DC/DC converter, a power distribution unit, a battery storage system, and a charging unit. This paper proposes a parallel active clamp isolated DC/DC converter with high efficiency for a 20 kW emergency rescue mobile charging system. The topology is improved so that switching loss is reduced by ZVS turn-on, the current flow in clamp switch is distributed, and the switching frequency of clamp switches is the same as the switching frequency of main the switches. The voltage gain, which is defined as the ratio of the input–output voltage, is derived. Moreover, the design of leakage inductance for ZVS operation, the calculation of dead-time range based on switch specification, the influence of parasitic resistances such as input inductor and transformer, and load resistance on voltage gain are fully analyzed. The effectiveness of the proposed converter is verified through simulation and experimental analysis.

키워드