Interleaved active-clamping converter with ZVS/ZCS features

In this paper, an interleaved soft-switching dc-to-dc converter configuration is proposed. It consists of two parts: the primary side is a constant-frequency asymmetrical converter with active clamp feature and the secondary side is a series resonant tank circuit. The active clamp circuit recycles the energy stored in the magnetizing inductance of transformer to allow main/auxiliary switches turn-on at zero-voltage switching and clamps the voltage stress of the main switches. Series resonant tank circuit employs the transformer leakage inductance and secondary resonant capacitance to achieve zero-current switching of the output diodes. The circuit features constant-frequency operation and soft switching for both the transistors and the diodes. Interleaving operation of this configuration combines the aforementioned benefits and small output capacitor. Theoretical analysis of the converter were given. An 80-KHz 500-Watt experimental circuit of the proposed converter was demonstrated.