Repetitive PI compound control of cascaded single-phase PFC system

The electric vehicle charger brings convenience to people's daily travel, but faces the problems of slow charging speed and low charging efficiency. This paper proposes a cascaded single-phase PFC (Power Factor Correction) solution based on repetitive PI (Proportional Integral) compound control. The main circuit of the system adopts cascaded multilevel structure of low-voltage devices. It can effectively increase the system power density of the charger, reduce the voltage required for a single switch, and improve the power factor of the system output. The system control adopts double-loop control mode, in which the voltage outer loop adopts PI control and the current inner loop adopts repetitive PI compound control. It uses the characteristics of precise tracking of repetitive control and fast response of PI control to reduce the distortion rate of system input current and effectively increase the dynamic stability of the system. The effectiveness of the proposed scheme is verified by simulation and experimental results.