Abstract:
A totem-pole bridgeless power factor correction (PFC) circuit topology with zero-voltage switching (ZVS) and zero-current switching (ZCS) for continuous conduction mode (CCM) was proposed. Based on the traditional totem-pole bridgeless PFC circuit, the auxiliary resonant branch was added to realize ZVS conduction of the main switches (MOSFETs). At the same time, the auxiliary resonant branch could effectively suppress the d
i/d
t of the current flowing through the MOSFET body diodes, which made the MOSFETs turn off with ZCS. It greatly alleviated the reverse recovery problem of MOSFET body diodes. The auxiliary resonant branch operated in the discontinuous conduction mode. All the auxiliary switches of the converter turned on with ZCS, and all switches of the converter worked in soft switching state. The topology overcame the reverse recovery of MOSFET body diodes in traditional silicon-based totem-pole bridgeless PFC and the limitation that it only works in the discontinuous conduction mode (DCM) or boundary conduction mode (BCM). It widened the working range, and had higher efficiency and power density than the traditional totem-pole bridgeless PFC circuit. Finally, a prototype of AC/DC bridgeless PFC was constructed to verify the feasibility and effectiveness of the topology.