Implementation of an interleaved ZVS/ZCS DC/DC converter

This paper 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 adopted circuit not only to absorb the energy stored in the leakage inductor but also to achieve ZVS turn-on feature for power switches. On the other hand, the resonant tank composed of the leakage inductance and resonant capacitance at the secondary side is used to achieve ZCS turn-off feature for 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 and the circuit efficiency is improved. The interleaved pulse-width modulation (PWM) is used to control two converter cells to achieve load sharing and input ripple current reduction. Laboratory experiments with a 400W prototype, verifying the effectiveness of the proposed converter, are described.