A novel ZVZCS phase-shifted full-bridge converter with secondary-side energy storage inductor used for electric vehicles

This paper presents a novel ZVZCS phase-shift full-bridge (PSFB) DC-DC converter with secondary-side energy storage inductor, which can be utilized in high voltage application such as electric vehicle. By employing an energy storage inductor and an output capacitive filter at the secondary side, there is little reverse recovery loss in output-diodes due to relatively slow downslope of the triangular current. Meanwhile, the voltage spike across the output diode can be also eliminated and clamped by the output capacitor directly. Moreover, the proposed converter introduces a passive auxiliary circuit to satisfy the ZVS operation of the converter from no-load to full-load conditions resulting in superior efficiency in very wide load variations. Finally, the operational principle and analysis of the proposed converter are presented in detail. Experimental results provided from a 1kW prototype verify the feasibility and superior performance of the proposed converter.