In response to the problems of traditional PMSM speed-current double closed-loop PI control system with easy overshoot of speed response and long dynamic time in the dynamic link, as well as large speed fluctuation after sudden load application in the steady-state link, a speed loop controller based on active disturbance rejection control strategy is adopted to replace the PI controller, and the second-order active disturbance rejection controller used is improved. A variable structure is adopted to allow the extended state observer ESO to observe the input error of the active disturbance rejection controller, Re derive and construct the observer and disturbance compensation loop to further improve the stability of the PMSM control system and accelerate response speed compared to traditional active disturbance rejection controllers within a reasonable range of parameters. Simulate modeling using Simulink and build a hardware experimental platform for theoretical verification. Compare the speed response of traditional second-order active disturbance rejection controller and improved second-order active disturbance rejection controller under the conditions of unified controlled object and unified input signal, respectively. Finally, it is concluded that the improved active disturbance rejection controller has faster response speed, smaller overshoot, and better stability in the PMSM control system.