For sensorless control in the full speed range of PMSM, in the zero speed section and low speed section, the pulse vibration high frequency injection method is currently dominant. In this method, the parameter variations, inverse potential and cross-coupling terms have an impact on the rotor position estimation error, and the rotor position estimation error is obvious; in the medium and high speed sections, the sliding mode observer is currently dominant. Conventional counter potential sliding mode observer has a large amount of noise disturbance in the output counter potential due to its...