Research of permanent magnet servo system based on disturbance observer and Kalman filter

Speed control precision of permanent magnet servo system is affected by factors of the load torque disturbance and speed measure noise, the system dynamic and anti-disturbance performance have been greatly restricted. Disturbance observer used as a kind of effective method to restrain the disturbance of load torque change, has attracted extensive concern of many scholars. However, a larger observation noise restricts disturbance rejection. In this paper, Kalman filter is applied for speed estimation to effectively reduce noise, and the estimated speed is input to disturbance observer. The disturbance observer outputs the observation value of load torque, which is used for the feed-forward compensation of torque current to compensate for speed fluctuation caused by load disturbance. Simulation and experiments have been built to verify the correction of theory analysis.