Analysis, design and implementation of an active snubber zero-voltage switching cuk converter

A zero-voltage switching parallel-connected Cuk converter is presented. Active snubber circuit is used in the converter to achieve soft switching and to limit voltage stress across power switches. In the proposed converter, the primary windings of two transformers are connected in series. Two half-wave rectifiers are connected in parallel at the output side to reduce the current stresses on the secondary winding of the transformer. The constant pulse-width modulation scheme is adopted to regulate the output voltage. The principle of operation and system analysis of the proposed converter are presented. Experimental results for a 300 W (12 V/25 A) prototype circuit operating at 70 kHz switching frequency are given to demonstrate the effectiveness of the proposed converter.