Implementation of a soft switching DC/DC converter without reverse recovery loss for rectifier diodes

This study presents an interleaved soft switching converter to achieve ripple current reduction, zero-voltage switching (ZVS) turn-on for MOSFETs and zero-current switching (ZCS) turn-off for fast recovery diodes. Active snubber circuit is used in the proposed circuit to absorb the energy stored in the leakage inductor and to achieve ZVS turn-on for power switches. The resonant tank composed of the leakage inductor and the resonant capacitor at the secondary side is used to achieve ZCS turn-off for all rectifier diodes. The reverse recovery loss on rectifier diodes can be eliminated. Thus, the low-cost fast recovery diodes can be used at the secondary side. The interleaved pulse-width modulation scheme is used to control two converter cells in order to achieve load sharing and input ripple current reduction. Experiments with a 400 W prototype, verifying the effectiveness of the proposed converter, are described.