Soft-switched PFC boost rectifier with integrated ZVS two-switch forward converter

A soft-switched continuous-conduction-mode boost PFC front-end converter with an integrated zero-voltage-switched two-switch forward second-stage converter is introduced. In the proposed approach, a single transformer is commonly used by the two stages to provide isolation of the power supply and soft switching of all semiconductor switches including a controlled di/dt turn-off rate of the boost rectifier. The performance of the proposed approach was evaluated on a 150-kHz, 430-W/12-V, universal-line range prototype converter