Inductor‐based auxiliary circuit‐assisted ZVS in full‐bridge dc–dc converter for EV applications

This study proposes an efficient soft-switched full-bridge DC/DC converter (FBDC) topology operated with modified pulse width modulation (MPWM) for electric vehicle (EV) battery chargers, as the role of DC/DC converter is more prominent in on-board charging. The proposed auxiliary circuit offers zero voltage switching (ZVS) turn-on to all the active switches of the converter during full battery charging range. In consequence, the losses associated with the proposed FBDC are minimal and offer maximum efficiency as compared to available benchmark topologies operated with different gating schemes. The size of magnetic elements used in the proposed topology also reduced as to conventional FBDC operating with trailing edge pulse width modulation and phase shifted modulation gating techniques. A detailed designing and analysis of the MPWM operated ZVS FBDC is presented. Besides, the rationale behind the selection of switching frequency in order to ensure wide-range ZVS is detailed. Further the proposed topology is compared with the other competent topologies for proving its significant merits. Simulation of the proposed configuration is performed at 3.3 kW. Following which, the experimental results obtained from a laboratory prototype of 500 W, 80 kHz validating the operability and feasibility of the proposed converter are presented.