Abstract: Sensorless control of PMSM can significantly improve the robustness and reliability of the drive system and reduce the cost. Aiming at the problem of system performance degradation caused by filtering in sensorless control based on high frequency signal injection, an improved sensorless control strategy based on moving average filtering is proposed. First of all, based on the analysis of the high frequency signal processing part of current loop and the rotor position based on observed performance impact, a kind of sensorless control method based on moving average filter is put forward. Instead of the position error in the feedback path in the current loop and link of the traditional filter, the moving average filter is used in this method, the control performance without sensor system is improved. Experimental results show that the harmonic content of feedback current is reduced and the bandwidth of the system is effectively improved in this method. At the same time, the high frequency current can be extracted effectively and the dynamic performance of position observation can be improved.