A novel ZVS full-bridge converter with auxiliary circuit

A novel full-bridge (FB) pulse-width-modulated (PWM) converter features zero-voltage-switching (ZVS) of all primary switches in the entire line and load range is described. In contrast to conventional full bridge converter, ZVS is achieved by utilizing energy stored in inductive components of the auxiliary circuit. The auxiliary inductors do not appear as series inductances in the power transfer path, so they do not cause severe voltage ringing across the output rectifier or duty cycle loss. The operation principle of the circuit is analyzed and design considerations of the converter are discussed. Finally, the experimental results from a 1-kW (54-V/20-A) prototype are presented to confirm the operation, validity, and features of the proposed converter.