A Novel Three-phase Buck-type Rectifier and Its Analysis

Abstract

A new three-phase buck-type PFC rectifier is presented in this paper. The efficiency is improved since only two of the switches are working at high frequency while the rest are in the low-frequency state. Firstly, the various switching states of the PFC rectifier are analyzed and the working rules of the two high-frequency switches are illustrated. On one hand, the two high-frequency switches performance as the ordinary BUCK circuit to guarantee the stability of the output voltage, on the other hand, by adjusting duty ratios of high-frequency switches, the three-phase input current is controlled. Then, the modulation is discussed and the design of corresponding controller is given. Finally, the effectiveness of the buck-type PFC rectifier is verified through simulations and experiments.