Influence of high-frequency leakage current on motor position control in PWM inverter-fed servo drives

Progress of power semiconductor devices has contributed to realizing high-performance power converters and precise servo drives. However, high-speed switching of the power devices may cause 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 an influence of the high-frequency leakage current to motor positioning and describes its mechanism. Some experimental and simulated results show that the high-frequency leakage current may cause motor position variation at twice of line frequency.