Wide zero‐voltage switching range full‐bridge converter based on adjustable parallel current

Abstract

Aiming at the problems of narrow ZVS range, large duty cycle loss, and severe voltage oscillation of phase‐shift‐controlled full‐bridge converters, this paper proposes a converter that realizes ZVS by adjusting the parallel current. No additional series inductor is required, avoiding large duty cycle loss and weakening voltage oscillations on the secondary side. The converter with small duty cycle loss can use a transformer with a larger turns ratio, which can reduce the voltage stress of the secondary diodes and the filter inductor current ripple. The parallel current required to realize ZVS is analyzed theoretically considering the influence of leakage inductor energy on ZVS. A comparative experiment between the proposed converter and the conventional full‐bridge converter is carried out to verify the performance of the proposed converter.