Predictive control method with conduction mode detection to suppress input current distortion of three-level power factor correction

A novel predictive control method with conduction mode detection is proposed to suppress input current distortion of three-level power factor correction (PFC) converters. In PFC converter, the input current is mostly distorted in continuous conduction mode (CCM) with conventional control methods. The proposed predictive control method comprises of a predictive CCM algorithm, a predictive discontinuous conduction mode (DCM) algorithm, and a conduction mode detection technique. By analysing four switching states of PFC converter and based on the inductor current ripple, predictive control duty cycles in CCM and DCM are derived, and the optimal duty cycle is determined by forecasting the next cycle current. According to the duty cycle characteristics, the conduction mode is detected without additional detection algorithms and circuits, achieving the input current tracking the input voltage. Finally, the effectiveness and correctness of the proposed predictive control method are validated through simulation and experiment.