An Improved Super-Twisting Sliding Mode Controller Over Totem-Pole Power Factor Corrector

The duty ratio of the Totem-Pole PFC will significantly change near the zero-crossing point of the grid voltage, resulting in potential overshoot and slow dynamic response when using Proportional-Integral control. Meanwhile, the conventional sliding mode algorithm leads to chattering phenomenon and noticeable current distortion near the zero-crossing point. To reduce this zero-crossing distortion, various methods can be designed. However, it is crucial to focus on improving control strategies for enhanced universality and versatility. In this study, an improved Super-Twisting Sliding Mode Controller is proposed by selecting a suitable sliding surface and introducing either the square of the error or the square difference of the error with feedback as controller inputs. Simulation and experimental results show that this approach effectively accelerates system dynamics, enhances steady-state performance, improves input current waveform at zero-crossing point of the grid voltage, increases input power factor, and reduces input current total harmonic distortion.