电液伺服系统的微分与积分滑模变结构控制

针对电液系统的非线性特性及其参数不确定性,在电液伺服系统的速度跟踪控制中,提出了一种非线性微分与积分滑模变结构控制(DI-SVSC)策略。在滑模控制中引入积分控制项,消除了传统滑模变结构控制需要被跟踪信号导数已知的假设,利用一非线性微分控制消除了系统的抖振现象。在积分滑模控制与非线性微分控制中,分别给出了切换函数、非线性微分系数及控制器的设计方法。仿真结果显示,该控制方法具有较强的鲁棒性及良好的跟踪性能。

Derivative and integral sliding mode variable structure control of electro-hydraulic g system

This paper studies the velocity tracking control of an electro-hydraulic servo system. Since the dynamics of the system are highly nonlinear and have large extent of model uncertainties including big changes in load and hydraulic parameters, a derivative and integral sliding mode variable structure control scheme (DI-SVSC) is proposed. An integral controller is introduced to avoid the assumption that the derivative of desired signal must be known in conventional sliding mode variable structure control. A nonlinear derivative controller is used to weaken the chattering of system. Present the design method of switching function in integral sliding mode control, nonlinear derivative coefficient and controllers of DI-SVSC respectively. Simulation shows that the control approach has nice robustness and improves velocity tracking accuracy considerably.