A Novel Error Exponential Convergence Law Fractional Order Integral Sliding Mode Control for PMSM Based on ILC-DOB

This paper proposes a fractional-order integral sliding mode control (FOISMC) to address the problems of excessive tracking error, slow dynamic response and poor interference immunity in the speed loop control of permanent magnet synchronous motor (PMSM). The fractional-order integral sliding mode surface is proposed by inserting an integral term to the traditional fractional-order sliding mode surface, and a new error exponential convergence law is designed by introducing |e| and ${e^{ - {k_3}|e|}}$ into the exponential convergence law. An improved fractional-order integral sliding mode controller is designed based on the proposed sliding mode surface and the convergence law in place of the traditional PI controller, and a new continuous function f (s) is used instead of the sign function to attenuate the system chattering. However, there are load disturbances in real permanent magnet synchronous motor (PMSM), and in order to minimize the effect of load disturbances on the control performance, the fractional order integral sliding mode control is combined with an iterative learning-based disturbance observer (ILC-DOB) to further improve the control performance of PMSMs. The stability of the proposed control method is demonstrated by Lyapunov function. Finally, the permanent magnet synchronous motor model is built in Matlab/Simulink and compared with the sliding mode control (SMC) and terminal sliding mode control (TSMC) methods, respectively, and the experimental results show that the proposed FOISMC combined with iterative-learning-based disturbance observer can improve the control accuracy of the PMSMs, accelerate the dynamic response, and make the system more resistant to interference. make the system have stronger anti-disturbance ability.