An Active Partial Switching Method in Tertiary Loop for a High-Efficiency Predictive Current-Mode Control PFC Converter

This paper proposes a novel active partial switching method for a boost power factor correction (PFC) converter, based on the predictive current mode control to achieve both current shaping capability and high power conversion efficiency. This method consists of a controller that maintains a switching stop angle near the peak voltage of the input voltage by means of output voltage control, and an adaptive current shaper that adjusts the switching stop period near the zero voltage of the input voltage based upon the load condition. The proposed method shows good PFC performance and high efficiency even under various disturbances such as input voltage and load fluctuations. Moreover, it has the advantage that it is possible to achieve high efficiency even under conditions of output voltage exceeding the peak value of the input voltage. For sequential explanation, this paper illustrates the design of the controller based on the frequency-domain response and provides theoretical analysis of the proposed method. Finally, to verify the effectiveness of the proposed method, experimental results are presented based upon a 2.4 kW boost PFC converter prototype.