The inverter switching cabinet based on PLC control system is used to improve the power supply system and control system of the main fan in Gucheng Coal Mine. The inverter switching cabinet is connected to the original main fan power supply system of Gucheng Coal Mine, and the switching cabinet control substation is added to the original control system to realize the local and centralized control of inverter switching. Field operation results show that the inverter switching control system based on PLC can achieve efficient switching between inverters, so that the reliability of the main fan operating system is significantly improved.