A fully soft-switched multiphase DC-DC converter with reduced switch count for high power application

This paper proposes a fully soft-switched multiphase dc-dc converter for high power application. The proposed multiphase converter exhibits low switch count and simple gate driver circuit. Owing to use of low rated lossless passive clamp and series resonant circuits, ZCS turn-on and ZVS turn-off of switches and ZCS turn-off of diodes are achieved. Further, despite the passive clamp method, operating duty cycle range is not limited, resulting in no additional start-up circuitry required. Experimental results on a 50kHz, 5kW prototype are provided to validate the proposed converter.