SiC-Based High-Frequency Soft-Switching Interleaved Totem-Pole Bridgeless PFC Converter without ZCD Circuits

Under the traditional control methods for totem pole bridgeless PFC converter, zero-crossing detection (ZCD) circuits or additional auxiliary circuits are required to achieve soft-switching, which will increase circuit cost and control complexity. To solve this problem, a digital control strategy based on a variable switching frequency without ZCD circuits is proposed to achieve zero-voltage-switching (ZVS). Besides, a two-phase interleaved parallel structure is adopted to further reduce the current ripple and improve quality of the current waveform. Finally, a 2kW prototype is built to verify the effectiveness and advantages of the proposed method.