Optimization of Subway Three-Phase PWM Rectifier Combining Sliding Mode Variable Structure Control and Passivity-Based Control

Three phase PWM (Pulse Width Modulation) rectifiers have become a key technical means to solve the problems of harmonic and reactive power "pollution" in the power grid caused by rectification devices, due to their excellent abilities in achieving sinusoidal input current, ensuring unity power factor operation, supporting bidirectional power flow, and maintaining constant output voltage. This characteristic is of great importance for maintaining the stable operation of the power grid, especially in complex systems such as subways that require extremely high power quality. In this paper, the optimization method of the subway 3-phase PWM rectifier is studied. By combining sliding mode variable structure control (SMC) and passive control, the performance of the rectifier is improved. SMC, with its strong robustness and fast response speed, can significantly improve the adaptability and stability of the rectifier in dynamic changing environments; Passive control further enhances the efficiency and stability of the rectifier by optimizing the internal energy flow of the system. The experimental results show that after adopting this comprehensive optimization method, the performance of the subway three-phase PWM rectifier has been significantly improved.