Novel three-level power factor corvect circuit with passive soft switching

The paper presents a novel single phase there-level PFC circuit with passive soft switching. The three-level Buck and Boost topologies are derived from the traditional diode clamped three-level inverters' bridge leg firstly. Then, a single phase three-level PFC circuit is discussed based on the three-level BOOST topology. Two passive soft switching snubber cells are added to three-level PFC circuit to soften the switching processes of the switches and freewheeling diodes. It's operating principle and design considerations are discribed in detail. At last, a 2kW prototype of the single phase three-level PFC with the passive soft switching is built and tested. The simulated and experimental results show that the circuit can realize the three-level PFC function and increase system efficiency as well as have no over-voltage stress on main power switches.