A Three‐Level Boost PFC Converter With Active Power Decoupling

ABSTRACT

Boost‐type power factor correction (PFC) circuits are widely used in high‐power rectifiers due to their adjustable input current and continuous conduction mode (CCM) operation. However, the boost structure imposes high reverse voltage stress on the switching transistor. The three‐level boost PFC reduces this stress by adding a switch and splitting the DC‐side capacitor into two, but the inherent single‐phase power imbalance still introduces a twice‐line‐frequency ripple voltage, causing output fluctuation and input current harmonics. To address this issue, an improved three‐level boost PFC topology where two diodes are replaced with fully controlled switches is proposed in this paper, forming a half‐bridge active power decoupling circuit (APDC) on the DC side. By controlling these switches, counterphase AC voltage components are generated across the split capacitors, eliminating the second‐order harmonic DC voltage ripple. The paper analyzes the operating principles and control strategy of the improved circuit, compares its performance with the conventional topology through simulation, and validates the approach using an experimental prototype. Experimental and simulation results demonstrate that the proposed converter achieves a 91.7% fluctuation power suppression and a 40% DC voltage ripple reduction under rated operating conditions, while maintaining a power factor higher than 0.99 and low input current total harmonic distortion.