Research on electromagnetic disturbance and its radiation level of an EMUs' traction inverter

As one of the main EMI sources, the traction inverter of EMUs or electric locomotive produces large amount of harmonics and chopper switching noise when it works. It may cause hazard effects or electromagnetic interference to traction motor, track circuit system and ATP system, which may seriously affect the safety of train running. A traction inverter model is proposed in this paper to simulate and study the electromagnetic disturbance that generated by the inverter. Based on the simulation, the common mode noise current of the inverter's output and the radiation level are evaluated. Simulated radiated disturbance result shows good appliance to the experimental tests of a realistic inverter which connected to a motor. The approach explains the disturbance characteristics of inverter and the mode of its emissions.