Flexible PFC control featuring adaptive gain, mode estimation, and dual feedforward compensation

The performance and stability of Power Factor Correction (PFC) circuits is imperative to the efficiency of ac power systems and their respective loads. Since PFC converters may operate over a wide load range and support various peak input voltages, their controller should be designed for adaptability. In this paper, an adaptive Mixed Conduction Mode control algorithm which predicts the conduction mode and adjusts the feedback gain and feedforward signals is presented. This strategy is shown to expand the operating range and enhance the input current regulation of a bridgeless boost PFC converter through simulation in PSIM and on a hardware in the loop implementation in OPAL RT.