基于改进等速趋近律的PMSLM无传感器控制研究

Research on Sensorless Control of PMSLM Based on Improved Constant Speed Reaching Law

在永磁同步直线电机无传感器控制中,滑模观测器在运行过程中会出现明显的抖振现象,如何削弱抖振、提高无传感器控制系统的滑模观测器控制精度成为滑模控制应用的一大难题。提出了一种基于改进等速趋近律的滑模观测器,将符号函数替换为具有光滑连续特性的双曲正切函数,并且在正交锁相环中引入模糊PI来对动子速度、位置信息进行估计。通过在Matlab/Simulink中搭建永磁同步直线电机的无传感器控制系统模型,对所设计的滑模观测器运行效果进行仿真验证。结果表明,上述方法能够有效的削弱系统的高频抖振,同时能够提高控制精度,控制效果良好。

In sensorless control of permanent magnet synchronous linear motor(PMSLM),the chattering phenomenon of sliding mode observer is obvious in the process of running.How to reduce chattering and improve control accuracy has become a hot issue to be solved in sliding mode control.In this paper,a sliding mode observer based on the improved isokinetic approaching law is proposed.The hyperbolic tangent function is used to replace the chattering sign function,and fuzzy PI is introduced into the orthogonal phase-locked loop to estimate the velocity and position of the linear electric motor.The sensorless control system model of a permanent magnet synchronous linear motor was built in Matlab/Simulink,and the operation effect of the designed sliding mode observer was simulated and verified.The results show that this method can effectively weaken the high-frequency chattering of the system and improve the control accuracy,and the control effect is good.