基于改进指数趋近律和自适应龙伯格观测器的PMSM速度环滑模控制

Sliding mode control strategy for PMSM speed ring based on improved exponential convergence law and adaptive Lunberger observer

为了提高永磁同步电机驱动系统的速度控制性能,提出一种基于改进指数趋近律和自适应龙伯格观测器的滑模控制策略。针对传统指数趋近律收敛速度慢的问题,提出一种基于非线性自适应函数的指数趋近律,基于该趋近律的滑模控制策略使系统具有更快的收敛速度和更小的抖振,引入的自适应函数解决了趋近律的指数项导数不连续的问题。针对传统的龙伯格观测器性能差的问题,提出一种自适应龙伯格观测器对系统的总扰动进行估计并补偿,该观测器具有更快的响应速度且不影响系统的稳态性能,进一步提升了系统的抗干扰能力和速度跟踪性能。仿真和实验结果表明,在跟踪500 r/min和750 r/min的阶跃速度指令时,系统的调节时间分别为0.44 s和0.71 s;突加5 N·m,10 N·m和20 N·m负载时,系统的调节时间分别为1.16,1.79和1.99 s。本文提出的滑模控制策略能够有效提高系统的稳定性和动态响应性能。

To enhance the speed control of permanent magnet synchronous motor(PMSM)drive sys⁃tems,this paper introduces a new sliding mode control(NSMC)strategy with an improved exponential convergence law and an adaptive Lunberger observer.Firstly,to overcome the slow convergence of traditional exponential laws,a nonlinear adaptive function-based law is proposed,enabling faster convergence and reduced jitter for the NSMC strategy.This adaptive function also resolves the discontinuity issue of the convergence law's exponential term.Secondly,addressing the limitations of the traditional Lunberger observer,an adaptive version is developed to estimate and compensate system perturbations,offering quicker response without affecting steady-state performance,thus enhancing the system's disturbance resis⁃tance and speed tracking.Simulations and experiments demonstrate that for step speed commands at 500 r/min and 750 r/min,the system's settling times are 0.44 s and 0.71 s,respectively.When loads sudden⁃ly increase by 5,10,and 20,the settling times are 1.16 s,1.79 s,and 1.99 s.The proposed sliding mode control strategy significantly improves both dynamic and steady-state system performance.