Controller design of servo drives for bandwidth improvement

The controller design of servo drives for bandwidth improvement will presented in this paper. The delay issues caused by calculation, fdter and PWM generation, etc. are addressed. The controllers of current loop, speed loop and position loop are designed considering the delay and phase margin. Experimental results show the bandwidth for current, speed and position loops of servo drives are significantly improved as compared to those using conventional methods. For the servo drives with switching frequency of 20 kHz, as compared to traditional design method, the achievable control bandwidth for the presented method of position control loop is improved from 20 Hz to 116 Hz.