基于扩张状态观测器的一类未知非线性不确定系统滑模控制  

Sliding-mode control for a class of unknown nonlinear systems with uncertainties based on extended state observer

作　　者：李永刚[1] 李星野[1] 史先鹏[2] 

机构地区：[1]上海理工大学管理学院,上海200093 [2]华东理工大学信息科学与工程学院,上海200237

出　　处：《上海理工大学学报》2010年第2期110-114,共5页Journal of University of Shanghai For Science and Technology

基　　金：上海市自然科学基金资助项目(06ZR14144);上海市教育委员会科研资助项目(07ZZ94)

摘　　要：研究了基于扩张状态观测器的一类n阶未知非线性不确定系统的滑模控制问题.在系统状态已知的前提下,利用滑模控制思想将一个n阶未知非线性不确定系统方程转化为一个关于切换曲面函数的一阶非线性方程,然后利用二阶扩张状态观测器来估计转化后的一阶非线性方程的非线性函数和扰动.为了消除滑模控制项所带来的抖振,引入边界层.利用Lyapunov函数证明了系统的稳定性,完成了系统输出跟随系统输入的目的.由于系统中存在扩张状态观测器,本文的控制方法不依赖于被控对象的数学模型,具有很强的鲁棒性.仿真的结果表明了本文方法的可行性.A method was presented to design sliding mode controller for unknown nonlinear systems with uncertainties based on the extended state observer.In the premise of the obtainable system states,an n-order non-linear system equation was transformed into a first-order non-linear system equation by sliding mode control,then the extended state observer（ESO） was used to evaluate the nonlinear function and the disturbance of the previously transformed first-order non-linear system equation.In order to compensate the estimation error of the nonlinear function and the disturbance;the switch part of sliding mode control was added according to the control law.The chattering caused by the switch part of sliding mode control was eliminated by inttoducing boundary layer.The stability of the system was proved by Lyapunov function.Because of the existence of an ESO in the system,the control method doesn＇t rely on mathematical model of the plant,and has very strong robustness.The simulation results show the feasibility of the method proposed.

关 键 词：不确定非线性系统 扩张状态观测器 滑模控制 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]