Sliding Mode Control of Permanent Magnet Synchronous Motors Based on Improved Reaching Law and Disturbance Observer

为了提高永磁同步电机转速控制的响应性能及鲁棒性，同时解决传统滑模控制中趋近模态存在的趋近时间和系统抖震幅值之间的固有矛盾，提出了一种基于改进自适应趋近律和扰动观测器的滑模控制方法。设计一种改进自适应趋近律，引入复合函数项并结合积分滑模面构造速度环滑模控制器。同时设计积分终端滑模扰动观测器，用于实时监测系统内部参数的变化及外部扰动，并将估计值前馈补偿给滑模控制器以抑制扰动的影响。仿真实验表明，提出的滑模控制方法有效提高了响应速度，突增负载时，转速波动小，恢复时间短。结果表明提出的滑模控制方法，可以有效改善永磁同步电机转速控制的动态性能，提高鲁棒性，抑制抖震现象，为实现高精度稳定的速度控制提供了切实可行的方案。In order to enhance the response performance and robustness of the speed control for permanent magnet synchronous motor (PMSM), and to address the inherent contradiction between the approach time and the system’s oscillation amplitude in the sliding mode control, an improved sliding mode control method based on an adaptive approach law and a disturbance observer has been proposed. This method introduces a composite function item and combines it with an integral sliding surface to construct a sliding mode controller for the speed loop. Additionally, an integral terminal sliding mode disturbance observer is designed to monitor the changes in internal parameters and external disturbances in real-time, and the estimated values are used to compensate the sliding mode controller to suppress the effects of disturbances. Simulation experiments have shown that the proposed sliding mode control method effectively improves the response speed, with minimal speed fluctuations and short recovery times when sudden loads are applied. The results indicate that the proposed sliding mode control method can significantly improve the dynamic performance of PMSM speed control, enhance robustness, suppress oscillation phenomena, and provide a feasible solution for achieving high-precision and stable speed control.