High-frequency equivalent circuit of an induction motor driven by a PWM inverter

This paper deals with the high-frequency equivalent circuits in an induction motor driven by a PWM inverter. The leakage current flows through stray capacitance among stator windings and iron core (frame) of the induction motor at the switching instants of the inverter transistors. The high-frequency equivalent circuits are derived based on the frequency characteristics of the high-frequency zero-phase impedance and line-to-line impedance of the induction motor. The validity of the derived equivalent circuits is confirmed by simulation and experimental results. (C) 2001 Scripta Technica, Elects Eng Jpn, 135(1): 65-76, 2001.