High-Efficiency Multiplexed Buck-Type PFC Converter

This paper proposes a high-efficiency PFC rectifier based on multiplexing the switches. Compared with a traditional six-switch PFC rectifier, the proposed rectifier extends the switches' active angle by making use of three bridge rectifiers. As a result, lower conduction resistance can be realized for switches. Consequently, system efficiency can be improved. Compared with a traditional six-switch PFC rectifier with doubled switches, the proposed rectifier can achieve almost the same efficiency improvement while no additional switches are needed. Since continuous inductor current is chopped and resulting current pulses cannot be injected into the grid directly, input filter design and resonance damping are discussed for the proposed rectifier. The controller design of the rectifier is analyzed. The inductor current reference is shaped considering the input voltage envelope and forward duties. Finally, the effectiveness of the proposed rectifier is verified through simulations and experiments.