摘要
控制系统的执行器经常发生各种未知的间歇性故障.如何有效地处理这些故障对系统的影响是一个难题.针对一类不确定严格反馈非线性系统,提出一种自适应CFB(Command filtered backstepping)控制方案解决了间歇性执行器故障的补偿问题.利用神经网络逼近控制器中的未知函数,并采用投影算子实时在线更新控制器中的估计参数使得参数估计值随着故障次数的累积而不断增加的问题被消除.提出改进的Lyapunov函数证明了所提出的方案能够保证所有闭环信号的有界性,同时建立了跟踪误差与Lyapunov函数跳变幅度,最小故障时间间隔,设计参数之间的关系.如果Lyapunov函数的跳变幅度越小以及两个连续故障之间的时间间隔越长,系统的稳态跟踪指标越好.通过迭代计算建立了暂态跟踪误差指标的均方根型界.该界表明了通过选择恰当的设计参数,可改善系统的暂态指标.仿真结果表明了所提方案的有效性.
Actuators of control systems frequently encounter various unknown intermittent faults.How to effectively handle the effects of such faults on the system is a difficult problem.In this paper,an adaptive command filtered backstepping(CFB)compensation control scheme is proposed for a class of uncertain strict-feedback nonlinear systems to address the issue of compensation for intermittent actuator faults.Neural networks are utilized in the controller to approximate unknown functions,and a smooth projection algorithm is adopted to update the estimated parameters in the controller such that the problem of parameter estimate increase with the accumulation of the number of faults is eliminated.A modified Lyapunov function is developed to prove that the proposed scheme can guarantee the boundedness of all closed-loop signals and,the relationship among the tracking error,jumping amplitude of Lyapunov function,minimum fault time interval and design parameters can be established.It is shown that if the jumping amplitude of Lyapunov function is smaller and the time interval between two adjacent faults is longer,the system steady-state tracking performance is better.A root mean square type of bound for the transient tracking error performance is established by using iterative calculation to illustrate that the system transient performance is improved by appropriate choice of design parameters.Simulation results validate the effectiveness of the proposed scheme.
作者
乃永强
杨清宇
周文兴
杨莹
NAI Yong-Qiang;YANG Qing-Yu;ZHOU Wen-Xing;YANG Ying(School of Automation Science and Engineering,Xi'an Jiaotong University,Xi'an 7100492.China;Astronauts Research and Training Center,Beijing 100094;State Key Laboratory for Turbulence and Complex Systems,Department of Mechanics and Engineering Science,College of Engineering,Peking University,Beijing 100871)
出处
《自动化学报》
EI
CAS
CSCD
北大核心
2022年第10期2442-2461,共20页
Acta Automatica Sinica
基金
国家自然科学基金(61633001,61673315,61075001)资助。
关键词
自适应控制
CFB
非线性系统
间歇性执行器故障
Adaptive control
command filtered backstepping(CFB)
nonlinear system
intermittent actuator faults
作者简介
乃永强,西安交通大学自动化科学与工程学院博士研究生.主要研究方向为非线性系统,自适应神经控制,容错控制.E-mail:yongqiangnai@stu.xjtu.edu.cn;通信作者:杨清宇,西安交通大学自动化科学与工程学院教授.主要研究方向为信息物理融合系统,智能电网信息物理安全与隐私保护,复杂系统故障诊断与健康管理,工业智能控制.E-mail:yangqingyu@mail.xjtu.edu.cn;周文兴,中国航天员科研训练中心助理研究员,西安交通大学自动化科学与工程学院博士研究生.主要研究方向为环境控制与生命保障技术,测量与控制技术,传感器融合技术,装备健康管理技术.E-mail:zwxdzxx232@stu.xjtu.edu.cn;杨莹,北京大学工学院教授.主要研究方向为复杂动态过程故障诊断,容错控制与健康管理.E-mail:yy@pku.edu.cn。
