Robust Variable Structure Control for Compound Active-Clamp Three-Phase PFC Converter with Soft Switch

Abstract

Compound active clamping three-phase Boost PFC converter with soft-switch has a good potential application because of its high power factor, high efficiency and simple structure. The mathematical model of this converter is analyzed. A variable structure control method with the robustness item is proposed for the control of this converter, in order to overcome the shortcoming of the existing method, when the converter parameters changes. The time-varying boundary layer is used to smooth the control discontinuity. Simulation is performed using PSIM and MATLAB hybrid simulation method. The results indicate that the proposed method possesses not only better transient and steady state performance under the nominal parameters, but also better robustness under the parameter perturbations, compared with the traditional PI control and the former variable structure control without the robustness item.