In PMSM direct torque control system,rotor position information is usually needed to realize motor commutation operation,which is difficult to be used in some specific PMSM sensorless control.A sensorless direct torque control method of PMSM based on stator high frequency pulse flux injection was proposed.The electromagnetic torque and stator flux observer based on current model were designed.Only the measured current information was needed to realize the general control of high and low speed.Further,in order to realize the online identification of flux linkage and speed,the PMSM rotor position and speed observer was designed,and the pole judgment criterion was designed to improve the observation accuracy of the observer.Finally,the effectiveness and feasibility of the proposed scheme are verified by experiments.