Simulation Research on IGBT Snubber Circuit of Locomotive Emergency Power Supply Inverter

The emergency power supply inverter for electric locomotives provides comprehensive auxiliary emergency power supply for the locomotive driver's cab. The power electronic power device used is IGBT, and the switching frequency of the power device is relatively high (such as 20kHz). When it is turned off, a peak overvoltage will be generated, seriously threatening the withstand voltage value of the IGBT. In the actual inverter circuit, a buffer circuit is usually connected in parallel beside the IGBT. Five buffer circuits used for IGBT devices in emergency power supply inverters were described, their characteristics and application scopes were described. The buffer circuits of IGBTs were digital simulated using MAT LAB Simulink software, and the experimental waveforms and parameter optimizations were given, providing a reference for the design of emergency power supply inverters for locomotives.