Unknown Disturbance Compensation Control of PMSM based on Extended State Observer

There are many kinds of disturbances in the actual permanent magnet synchronous motor (PMSM) control system, including load sudden change, friction and others, which affect its speed control performance. The unknown torque disturbance and load torque in the PMSM system are considered to total disturbance using disturbance compensation control strategy in this paper, the extended state observer (ESO) is used to estimate the total disturbance in real time, and the feedforward compensation is applied to the speed loop controller to suppress the system disturbance. The trapezoidal wave disturbance and square wave disturbance are introduced in the PMSM system for simulation of the disturbance estimation and speed response, the estimation effects of total disturbance through output torque and input q-axis current are compared. The results show that the disturbance compensation control based on ESO can effectively suppress the unknown system disturbance, improve the speed tracking accuracy and enhance the robustness of the system.