Passivity-based control of four-phase interleaved PFC based on EL model

Based on the power circuit topology structure of the four-phase interleaved power factor corrector (PFC) that works in continuous conduction mode (CCM), this paper establishes its EL (Euler-Lagrange) mathematical model. The passivity of the four-phase interleaved PFC is proved and the passivity-based controller using the state variables feedback and damping injection method is designed. The proposed control scheme which is easy to control without proportion integral controller has strong robustness on disturbance of input voltage, load and parameters of system components. Especially in wide-range load condition applications, the dynamic response of input current is fast and the output voltage almost has no changes, therefore, the power factor correction and constant DC output functions of PFC are realized. Meanwhile, multi-phase interleaved PFC employing passivity-based controller has a good effect on current sharing. Simulation results prove that the passivity-based controller has a superior performance and the method is feasible.