Mitigation of Overvoltages at Induction Motor Terminals Fed from an Inverter Through Long Cable

Abstract

Fast switching speed of Insulated Gate Bipolar Transistors (IGBTs) inverters imposes the Induction Motor (IM) insulation system to steep voltage surges. Also, provides some secondary effects as bearing current, shaft voltages and Electromagnetic Interference (EMI). In this paper, different overvoltage mitigation methods are theoretically investigated with the aid of Power Simulation Program (PSIM) depending on the High-Frequency (HF) models of IM and long cable. These methods are line reactor at the inverter terminals, RC filter at the motor terminals, RLC filter at the motor terminals and RL filter at the inverter terminals. Based on the obtained results, a proposed overvoltage mitigation method is presented. The proposed method combines the advantages of line reactor filter at inverter terminals and RC filter at IM terminals. These advantages are theoretically as well as experimentally validated.