Modeling and simulation of a new Bridgeless SEPIC power factor correction circuit

A new Bridgeless PFC circuit based on Single-Ended Primary Inductance Converter (SEPIC) is proposed in this paper. The new topology has less component count and less conducted component during each mode of operation within one switching period. The small-signal and steady-state model of the circuit operated in Discontinuous Conduction Mode (DCM) is derived using the Current Injected Equivalent Circuit Approach (CIECA). The large-signal model based on state-space and switch model are also developed to verify the large-signal behavior. The simulation results of the proposed converter show that the output voltage of the proposed converter is successfully regulated to its desired value while the input current regulation is inherent.