Aiming at the parameter uncertainty and load torque disturbance of permanent magnet synchronous motor system, a terminal sliding mode control algorithm for permanent magnet synchronous motor based on the reaching law is proposed. First, a sliding mode control algorithm for sliding mode reaching law is proposed, which can dynamically adapt to the changes in system state. Second, a sliding mode disturbance observer is designed to estimate the lumped disturbance in real time and to compensate the controller for disturbance. On this basis, an online identification method based on disturbance observer for viscous friction coefficient and moment of inertia is used to reduce the influence of parameter uncertainty on the control system. Simulation and experimental results show the effectiveness of the method.
