Grounding Effect on Common Mode Interference of Coal Mine Inverter

摘要

This paper put forward a new model to analyze the grounding effect on common mode interference of underground PWM inverter. Taking into account the grounding method,tbe author establishs a common mode equivalent circuit of underground inverter.After Comparison of calculation results by Matlab software simulation ,it can be conclude that ungrounded neutral of transformer could redue common mode current in PWM system, but not very effective, the most efficient way is to increase grounding impedance of inverter and motor.