Phase-Shifted Full Bridge DC-DC Converter with Energy Recovery Clamp and Reduced Circulating Current

This paper introduces a full bridge converter with reduced circulating current and a reduction of the switch conduction and turn-off losses achieved by an energy recovery secondary clamp circuit. The proposed clamp circuit allows the converter to operate with wide input or output voltage range with minimum voltage stress across the output diodes. The paper describes an experimental 25 kW (1500 V, 16.7 A) full bridge converter operating at 32 kHz switching frequency. Losses and efficiency of the experimental prototype compare favorably against the standard full bridge and previously proposed zero-voltage/zero-current switching configurations.