Sensorless Control of Permanent Magnet Synchronous Motor Based on Adaptive Sliding Mode Observer

For the sensorless control method of traditional sliding mode observer, the high frequency harmonic content in the fundamental wave of Counter-electromotive force is high, the dither is serious, and The error of rotor position estimation is relatively large. In this paper, a sensorless control method of PMSM with adaptive sliding mode observer is proposed. Firstly, the adaptive rate of Counter-electromotive force is constructed, and the adaptive rate satisfies the stability of Lyapunov function. The adaptive sliding mode observer is constructed, which can rapidly reduce the observation error of Counter-electromotive force. In the rotor position estimation process, a phase-locked loop method is adopted, and a rotation impact elimination link is added to the traditional phase-locked loop, the effect of speed change is eliminated and the observation accuracy of sliding mode observer is improved. Finally, set up in Matlab/simulink simulation model. The results show this approach can effectively suppress sliding mode dither, reduce high-frequency harmonics in Counter-electromotive force, the high frequency harmonics in the Counter-electromotive force are reduced and the precision of rotor position observation is to improve.