Influence of High-Frequency Leakage Current on Motor Position Control in PWM Inverter-Fed Servo Drives

Abstract

Advances in power semiconductor devices have contributed to the realization of high-performance power converters and high-precision motor positioning. However, high-speed switching of power devices lead to a high-frequency leakage current and/or electromagnetic interference (EMI). On the other hand, it has been considered that the leakage current has no relation to motor position control in servo drive systems. This paper analyzes the influence of the high-frequency leakage current on motor positioning and describes its mechanism. Experimental and simulation results show that the high-frequency leakage current may cause variations in the motor position with a frequency that is twice the line frequency.