一类具有未知增长率非线性系统全局输出反馈实际跟踪  

Global practical tracking by output-feedback for nonlinear systems with unknown growth rate

作　　者：闫雪华[1] 刘允刚[1] 

机构地区：[1]山东大学控制科学与工程学院,济南250061

出　　处：《中国科学：信息科学》2011年第6期704-715,共12页Scientia Sinica(Informationis)

基　　金：国家自然科学基金(批准号:60974003);教育部新世纪优秀人才支持计划(批准号:NCET-07-0513);教育部科学技术研究重点项目(批准号:108079);山东省优秀中青年科学家奖励基金(批准号:2007BS01010);山东省杰出青年基金(批准号:JQ200919);山东大学自主创新基金(批准号:2009JQ008)资助项目

摘　　要：本文研究了一类仅跟踪误差可量测不确定非线性系统的全局输出反馈实际跟踪问题.不同于现有文献,该控制系统具有依赖于不可测状态的增长且增长率为未知常数,并且只要求被跟踪信号及其一阶导数有未知界,因此直接推广现有结果难以解决上述控制问题.受相关镇定结果的启发,并通过灵活运用广义控制(universal control)和死区(dead zone)的方法与技巧,本文设计了自适应输出反馈控制器.主要结果表明,所设计的控制器能够确保跟踪误差经有限时间后收敛于设定的原点的任意小邻域,同时闭环系统的所有信号皆有界.仿真算例验证了理论结果的有效性.This paper is devoted to the global practical tracking by output-feedback for a class of uncertain nonlinear systems with only the tracking error measurable. Different from the closely related works, the systems have unmeasured states dependent growth with unknown constant rate, and the reference signal, as well as its first order derivative, has unknown bound. Mainly because of these, the tracking problem can hardly be solved by straightforwardly extending the existing results. In the paper, motivated by the related stabilization results, and flexibly using the ideas of universal control and dead zone, an adaptive output-feedback controller is designed to make the tracking error prescribed arbitrarily small after a finite time while keeping all the states of the closed-loop system bounded. A numerical example demonstrates the effectiveness of the theoretical results.

关 键 词：不确定非线性系统 全局实际跟踪 自适应控制 输出反馈 动态高增益 

分 类 号：TP13[自动化与计算机技术—控制理论与控制工程]