Abstract: In the PMSM speed-regulation system,the control performance will become worse when a load is added suddenly or some disturbances existing in the load.In order to solve this problem,a new control scheme which was designed by a technique of ADRC was represent in this paper.The load-mutation and load-disturbance were all contributed to an unknown disturbance and ADRC is used for system estimation,compensation and control.Simulations showed that this method can not only quicken the speed-response of system without over-shooting,but also reduce the error of the steady state,further more it is more robust to the load-mutation and load-disturbance.