Input current phase lag and closed loop compensation for three-phase PFC rectifiers based on one-cycle control strategy

The one-cycle control (OCC) strategy used in the PFC circuit was widely researched because of simple circuit and needless of the multiplier and sampling input voltage. But in the medium-frequency of input source and medium/high power conditions, the phase angle of the input current would lag the corresponding angle of the input voltage under the traditional OCC control strategy. The current phase lag issue with the conventional OCC three-phase medium-frequency VIENNA rectifier was analyzed in this paper, and the modified OCC control strategy was proposed for three-phase PWM rectifiers under medium-frequency input source and medium/high power conditions. The new control equation was derived, and the control system diagram and the realized method were also shown in this paper. The proposed modified OCC control strategy could compensate the input current's phase angle automatically with the load changing. The power factor of the rectifier could be improved and the efficiency of the system could be also increased. The experimental results verified the correctness of the theoretical analysis.