Sensorless Control Strategy of Permanent Magnet Synchronous Motor Based on Fuzzy Sliding Mode Controller and Fuzzy Sliding Mode Observer

This paper proposes a permanent magnet synchronous motor sensorless control strategy based on fuzzy sliding mode controller and fuzzy sliding mode observer. In order to improve the response speed of the system and the anti-interference ability of the system, a sliding mode controller (SMC) is used to replace the PI regulator in the speed loop. In order to suppress the chattering caused by sliding mode variable structure control and reduce the error caused by chattering, the SMC and sliding mode observer (SMO) are improved. An integral sliding mode surface is used in the SMC, and a continuous saturation function is used instead of a discontinuous sign function. The square of the speed error is introduced in the switch term of the exponential approaching law to improve the dynamic quality of approaching motion. The switching function in the SMO also uses a saturation function to suppress chattering caused by switching. Fuzzy rules are established to adaptively adjust the switching gain of the SMO and the parameters in the SMC's reaching law, which further improves the performance of the control system. Simulations and experiments prove that the proposed control strategy has the characteristics of small chattering, fast response speed, and strong robustness.