Adaptive Nonsingular Fast Terminal Sliding Mode Control for Permanent Magnet Synchronous Motor Based on Disturbance Observer

To shorten the response time of permanent magnet synchronous motor (PMSM) control system, improve the robustness of the system, and avoid the influence of system structure and parameters on the control effect, an adaptive non-singular fast terminal sliding mode control scheme based on disturbance observer (DOBANFTSMC) is proposed. Firstly, a nonsingular fast terminal sliding mode surface is used to design the sliding mode controller. Secondly, the disturbance observer is used to compensating for the unknown model of the system, so that the controller design does not need to know the structure and parameters of the system. At the same time, considering the unknown estimation error bounds of the observer, an adaptive law is designed in the controller to adjust the unknown estimation. The stability of the system is proved by the Lyapunov principle. Finally, the simulation and experimental results show that this method can track the load torque quickly, and the system has the advantages of small overshoot, small static error, fast speed, and high robustness.