Simultaneous quadratic performance stabilization for linear time-delay systems

1.INTRODUCTION The simultaneous stabilization problem is concerned with the design of a single feedback controller P stabilizing every member of a collection of systems that is M 1 , M 2, … , Mr. In this case, the controller P is called the simultaneous stabilization controller. The motivation behind the simultaneous stabilization problem stems from the stability requirement of a system operating in different modes. For example, an industrial plant may be subject to different modes owi…     

Delay-dependent state feedback robust stabilization for uncertain singular time-delay systems

The problem of robust stabilization for uncertain singular time-delay systems is studied.First,a new delay-dependent asymptotic stability criteria for normal singular time-delay systems is given,which is less conservative.Using this result,the problem of state feedback robust stabilization for uncertain singular time-delay systems is discussed.Finally,two examples are given to illustrate the effectiveness of the results.     

非线性时滞系统自适应输出反馈跟踪控制

针对一类参数化非线性时滞输出反馈系统,提出了一种自适应输出跟踪控制器的设计方案。引入时滞滤波器估计未知系统状态,采用backstepping技术设计控制律和参数自适应律,运用占优方法处理非线性时滞项,从而放宽了对非线性时滞函数的要求,实现了对给定目标轨线的全局渐近跟踪,同时保证闭环系统所有信号一致有界。基于Lyapunov-Krasoviskii泛函方法证明了整个闭环系统的稳定性。实例仿真说明了该方案的可行性。     

高阶随机非线性系统状态反馈镇定

针对一类高阶下三角随机非线性系统,提出一种新的镇定方案,采用增加一个幂积分的工具构建了一个全局稳定的光滑状态反馈控制律。通过反馈占有设计方法和Young不等式处理随机系统的非线性项,取消了对随机非线性系统反馈线性化和控制输入呈线性的要求,基于Lyapunov方法,证明了闭环系统依概率全局渐近稳定。最后,仿真实例说明了算法的可行性。     

动态输出反馈网络控制系统鲁棒控制器设计

研究了具有不确定时延的动态输出反馈网络控制系统鲁棒控制器设计问题.考虑小于等于一个采样周期的不确定时延,将动态输出反馈网络控制系统建模为含有不确定性的离散时变系统.利用Lyapunov理论和矩阵不等式方法,推导出系统鲁棒控制律存在的条件,并转化为矩阵不等式表示的可行性问题,从而可利用Matlab LMI工具箱来求解,以便构造鲁棒控制律.Matlab仿真算例说明分析方法和结果是有效可行的.     

Backstepping tracking control for nonlinear time-delay systems

1. INTRODUCTION The presence of time delay has a significant effect on system performance and destroys the stability of closed-loop system[1]. Therefore, the study on time-delay systems has important practical significance. Recen- tly,considerable progress has been made in this field[1~10]. According to the dependency of the designed contr-oller depends on the time delay, the control approa-ches for time-delay systems can be classified into two categories: delay-dependent[2~3,10] and dela…     

一类不确定时滞系统的滑模控制

考虑了一类同时存在状态不确定性和控制不确定性的时滞系统的滑模控制问题,通过采用李亚普诺夫方法和线性矩阵不等式(LMI)技术,给出了闭环系统渐近稳定的充分条件,而且滑模控制律和滑模面的设计可以利用线性矩阵不等式的解得到,证明了该滑模控制律能保证状态轨迹被驱动到指定的切换面上。仿真实验表明了算法的有效性。     

Adaptive control for a class of discrete-time time-delay systems with regard to delay parameter

The memory state feedback control problem for a class of discrete-time systems with input delay and unknown state delay is addressed based on LMIs and Lyapunov-Krasovskii functional method. Under the action of our designed adaptive control law, the unknown time-delay parameter is included in memory state feedback controller. Using LMI technique, delay-dependent sufficient conditions for the existence of the feedback controller are obtained. Finally, the effectiveness of the proposed design method is demonstrated by a numerical example.     

Universal construction of control Lyapunov functions for a class of nonlinear systems

A method is developed by which control Lyapunov functions of a class of nonlinear systems can be constructed systematically.Based on the control Lyapunov function,a feedback control is obtained to stabilize the closed-loop system.In addition,this method is applied to stabilize the Benchmark system.A simulation shows the effectiveness of the method.     

Semi-global stabilization via homogeneous output feedback for a class of nonlinear time-delay systems

The semi-global stabilization problem for a class of nonlinear systems with state time-delay is addressed in this paper. By using Lyapunov-Krasovskii functional method and homogeneous domination approach, a homogeneous observer and an output feedback controller with a scaling gain are designed. Then the scaling gain is adjusted such that the closed-loop system is semi-global asymptotically stable. A numerical example is presented to illustrate the effectiveness of the obtained results in this paper.     

Adaptive neural network tracking control for a class of unknown nonlinear time-delay systems

1 .INTRODUCTIONNeural network (NN) control has made great pro-gress in past decades[1 ~4]. In Ref .[1] , adaptivebounding design technique was applied to adaptiveneural control for a class of strict-feedback nonlin-ear systems . The requirement of a known boundon the network reconstruction error was removed.By introducing an integral Lyapunov function,anadaptive NN control approach was proposed forunknown strict-feedback nonlinear systems[2],where the controller singularity problem was …     

非线性不确定时滞系统观测器型鲁棒无源控制

将无源性概念引入到非线性不确定时滞系统中,研究了带有时滞和不确定性的非线性系统的鲁棒无源控制问题.首先,利用多层神经网络近似代替系统中的非线性部分,采用线性微分包含(LDI)技术来线性化该非线性环节.其次,基于LDI模型,构造适当的状态观测器和反馈控制器,利用Lyapunov稳定理论,通过一定的矩阵变换,将设计问题转化为线性矩阵不等式(LMI)的可行解问题.从而使控制器的设计简单易行.接着,引入无源化的损耗指标,给出具有指定损耗指标的鲁棒无源控制器设计方法.最后以Lo-gistic混沌系统为例进行仿真试验,结果表明该设计方法的有效性.     

基于观测器的一类不确定非线性系统自适应输出反馈控制

针对一类不确定非线性系统,基于非线性状态观测器采用回馈递推(Backstepping)设计方法提出了一种鲁棒自适应L2增益控制方案。该控制方案首先对系统的不可观测状态设计非线性状态观测器,在此基础上通过多步递推得到系统的控制律并设计了未知干扰的参数自适应律,使系统具有L2增益性能。同时把采用常规设计方法需要对过多参数进行辨识问题简化为只需对与未知干扰个数相同的参数进行辨识的问题,简化了控制器结构。最后通过仿真算例验证了所设计控制方案的有效性。     

Parameterized design of nonlinear feedback controllers for servo positioning systems

1 .INTRODUCTIONServo positioning systems are universal in industrialenvironment , where fast and precise positioning iscritical for higher productivity and better quality .Linear control technologies have been playing anactive role for this purpose , while nonlinear con-trol is relatively naive and is now meticulouslyfinding applications in the real world. However ,asmart combination of linear and nonlinear controltechniques , which takes full advantage of bothtechniques ,can lead to a mor…     

Delay-dependent state feedback robust stabilization for uncertain singular time-delay systems

The problem of robust stabilization for uncertain singular time-delay systems is studied. First, a new delay-dependent asymptotic stability criteria for normal singular time-delay systems is given, which is less conservative. Using this result, the problem of state feedback robust stabilization for uncertain singular time-delay systems is discussed, Finally, two examples are given to illustrate the effectiveness of the results.     

New delay-dependent stability criteria and robust control of nonlinear time-delay systems

This paper investigates the stability analysis and H_∞ control for a class of nonlinear timedelay systems,and proposes a number of new results.Firstly,an equivalent form is given for this class of systems by means of coordinate transformation and orthogonal decomposition of vector fields.Then,based on the equivalent form,some delay-dependent results are derived for the stability analysis of the systems by constructing a novel Lyapunov functional.Thirdly,the authors use the equivalent form and the obtained stability results to investigate the H_∞ control problem for a class of nonhnear time-delay control systems,and present a control design procedure.Finally,an illustrative example is given to show the effectiveness of the results obtained in this paper.It is shown that the main results of this paper are easier to check than some existing ones,and have less conservatism.     

一类切换时滞奇异系统的最优保成本控制

针对一类切换时滞奇异系统,对最优保成本控制问题进行了研究。利用Lyapunov函数方法和凸组合技术,给出了由线性矩阵不等式(linear matrix inequality, LMI)表示的保成本控制器存在的充分条件,并设计了相应的子控制器和切换规则。进一步,建立了一个具有线性矩阵不等式约束的凸优化问题,利用Matlab软件中的线性矩阵不等式工具箱求解,给出了最优保成本控制器的设计方法及闭环最小性能指标上界。仿真示例验证了该方法的有效性。     

不确定离散切换系统的状态反馈鲁棒控制

针对同时具有模型参数不确定性和外部扰动的一类离散切换系统,研究H∞其鲁棒控制和H2/H∞混合鲁棒控制问题。首先,基于多Lyapunov函数法分析了含有状态反馈控制器的离散切换系统的稳定性和H∞鲁棒控制问题。其次,基于线性矩阵不等式,通过建立和求解一个凸优化问题,给出不确定H2/H∞鲁棒控制的具有更小保守性的求解方法。最后,仿真算例验证了所提出方案的可行性。