Research on bridgeless Boost PFC with soft-switching

Low conduction loss is the main advantage of bridgeless Boost PFC topology. In order to decrease switching loss and further improve efficiency, a bridgeless Boost PFC circuit with passive lossless snubber circuit is proposed. Using this snubber circuit, the power switches turn off with ZVS (zero voltage switching) and turn on with near ZCS (zero current switching) and the fast-recovery diodes operate at ZVS turn-on and turn-off. Prototype with one-cycle control chip IR1150 is designed after analyzing bridgeless Boost PFC and passive lossless snubber circuit. Experimental results verify that the snubber circuit can reduce switching dv/dt, di/dt and switching loss; the power factor is higher than 0.99 and the efficiency reaches 0.97 at 1.0 kW.