基于反步控制的非线性干扰观测器的外部不确定干扰的电液位置伺服系统

由于电液系统中存在各种非线性因素以及不确定干扰,为提高电液位置伺服系统在干扰下的控制精度,以电液振动台为控制对象,建立非线性模型,利用干扰观测器对干扰力进行观测,并通过反步控制器进行削弱和补偿,利用李雅普诺夫理论保证闭环系统的全局稳定.对设计的控制器进行仿真和实验,模拟在有外界未知干扰力下的位置控制,实现对干扰的抑制.实验表明:该控制策略能够很好的提高电液位置伺服系统的跟踪性能.

A nonlinear disturbance observer based on backstepping control for an electro-hydraulic servo system with external uncertain disturbances

With consideration of nonlinear factors and external uncertain disturbances existed in an electro-hy-draulic position servo system,a nonlinear model based on an electro-hydraulic shaking table is built in order to improve tracking accuracy of a position reference signal. A nonlinear disturbance observer is employed to measure external unknown disturbances and a backstepping controller is designed for the electro-hydraulic position servo system with nonlinear mathematical model. The proposed controller can guarantee the stabilization of the position closed-loop system using Lyapunov theory. Simulation and experiment of the designed controller are made with the external unknown disturbances. Experimental results show that the proposed control strategy is effective to improve the tracking accuracy of the position reference signal of the electro-hydraulic position servo system.