Buck-Boost PFC Converter with Active Power Decoupling Capability Using Time-sharing Control

This paper proposes a single-phase buck-boost PFC converter with active power decoupling (APD) using time-sharing control. The features of the proposed circuit are; 1) PFC and APD capability without additional inductors by sharing circuit components and 2) a wide DC voltage control owing to the buck-boost operation. The proposed method is characterized by two operating modes, discontinuous current mode (DCM) and triangular current mode (TCM). At the DCM method, time-sharing control is achieved by operating PFC and APD during each zero current period. In contrast, the TCM method achieves zero-voltage switching when switching between PFC and APD operation. Thus, switching loss is reduced compared to the DCM method. The validity of the proposed circuit operated in DCM is experimentally demonstrated by a 200-W prototype. It was confirmed that the output current ripple at twice the grid frequency is reduced by 90% in the experiment. Furthermore, the operation of the proposed circuit operated in TCM is demonstrated by simulation.