DESIGN OF REDUCED‐ORDER FUNCTIONAL OBSERVERS FOR LINEAR SYSTEMS WITH UNKNOWN INPUTS

This brief paper presents new conditions for the existence and design of reduced‐order linear functional state observers for linear systems with unknown inputs. Systematic procedures for the synthesis of reduced‐order functional observers are given. Numerical examples are given to illustrate the attractiveness and simplicity of the new design procedures.     

一类非线性组合大系统的分散输出反馈鲁棒镇定

研究了不确定非线性子系统经不确定非线性互联而成的组合大系统,给出了其可分散输出反馈鲁棒镇定的充分条件,说明了所得结论的广泛适用性以及相似结构与全息特性的密切相关性.     

ROBUST STABILITY AND STABILIZATION OF A CLASS OF SINGULAR SYSTEMS WITH MULTIPLE TIME‐VARYING DELAYS

This paper deals with the problem of robust stability and robust stabilization for uncertain continuous singular systems with multiple time‐varying delays. The parametric uncertainty is assumed to be norm bounded. The purpose of the robust stability problem is to give conditions such that the uncertain singular system is regular, impulse free, and stable for all admissible uncertainties. The purpose of the robust stabilization problem is to design a feedback control law such that the resulting closed‐loop system is robustly stable. This problem is solved via generalized quadratic stability approach. A strict linear matrix inequality (LMI) design approach is developed. Finally, a numerical example is provided to demonstrate the application of the proposed method.     

线性不确定时滞系统指定衰减度鲁棒镇定

研究了一类线性不确定时滞系统时滞依赖型具有指定衰减度的无记忆状态反馈鲁棒镇定问题.所考虑的线性不确定时滞系统含有时变未知但有界的不确定参数和状态滞后.通过应用Razumikhin定理和Lyapunov定理,导出了系统鲁棒稳定且具有指定衰减度的判据和具有指定衰减度的无记忆状态反馈鲁棒镇定控制律存在的充分条件及相应的控制器设计方法.所得时滞相关的结果用一组线性矩阵不等式(LMI)表示.     

IMPROVED CONDITIONS FOR DELAY‐DEPENDENT ROBUST STABILITY AND STABILIZATION OF UNCERTAIN DISCRETE TIME‐DELAY SYSTEMS

This paper provides improved delay‐dependent conditions for the robust stability and robust stabilization of discrete time‐delay systems with norm‐bounded parameter uncertainties. It is theoretically established that the proposed conditions are less conservative than those discussed in the literature. The new approach proposed in this paper in a derivation of delay‐dependent conditions and involves the use of neither model transformation nor bounding techniques for some cross terms. A numerical example is provided to demonstrate the reduced conservatism of the proposed conditions.     

具输入饱和因子的广义系统的镇定

广义系统的镇定问题是广义系统理论的基本问题之一.为了研究具输入饱和因子的广义系统的镇定,首先利用代数方法,借助大系统分解原理,对具输入饱和因子的广义系统进行综合,给出闭环系统渐近稳定的判别条件.其次,给出了闭环系统E一渐近稳定的概念,利用广义Lyapunov函数方法,研究具输入饱和因子的广义系统,提出了合适的反馈控制,得到了具输入饱和因子的广义系统E一渐近稳定的判别定理.     

具有线性漂移的随机多模态系统的反馈镇定

研究具有线性漂移的、以Markov链为开关函数的多模态随机系统的反馈镇定,通过建立多模态随机系统的均方渐近平坦性定理,给出具有线性漂移的多模态随机系统和线性多模态随机系统的反馈镇定方案,并给出控制器设计中的计算方法,用仿真实例验证了该方法的效果.     

时滞线性区间系统的鲁棒稳定与鲁棒镇定

利用一个微分不等式给出了几类具有区间 系数的时滞系统的鲁棒稳定和鲁棒镇定的充分条件,这些条件只需判断一个常数矩阵是否为 M矩阵,使用方便．     

GENERALIZED QUADRATIC STABILIZATION FOR DISCRETE‐TIME SINGULAR SYSTEMS WITH TIME‐DELAY AND NONLINEAR PERTURBATION

This paper discusses a generalized quadratic stabilization problem for a class of discrete‐time singular systems with time‐delay and nonlinear perturbation (DSSDP), which the satisfies Lipschitz condition. By means of the S‐procedure approach, necessary and sufficient conditions are presented via a matrix inequality such that the control system is generalized quadratically stabilizable. An explicit expression of the static state feedback controllers is obtained via some free choices of parameters. It is shown in this paper that generalized quadratic stability also implies exponential stability for linear discrete‐time singular systems or more generally, DSSDP. In addition, this new approach for discrete singular systems (DSS) is developed in order to cast the problem as a convex optimization involving linear matrix inequalities (LMIs), such that the controller can stabilize the overall system. This approach provides generalized quadratic stabilization for uncertain DSS and also extends the existing robust stabilization results for non‐singular discrete systems with perturbation. The approach is illustrated here by means of numerical examples.     

非线性时滞系统输出反馈镇定

该文首次研究了一类非线性时滞系统的镇定问题.用Backstepping技术,给出了输出反馈控制器的构造性设计方法.     

时变时滞不确定系统的鲁棒输出反馈控制

研究了时变时滞不确定系统基于状态观测器的动态输出反馈实现鲁棒镇定的分 析和综合问题.所研究的系统不仅同时包含时变状态时滞和时变控制时滞,而且包含时变未 知且有界不确定参数.提出了确保该系统可通过输出反馈鲁棒镇定的充分条件,并将该充分 条件转化为线性矩阵不等式(LMI)问题,最终通过求解两个LMI来构造输出反馈控制律.     

任意切换下不确定线性切换系统的鲁棒镇定

1引言 切换系统是一类重要的混合系统,它的稳定性是研究最为集中的问题之一.目前已引起国内学者的广泛关注[1,2].     

非线性最小相位系统输出反馈镇定的一个注记

讨论了单输入单输出非线性最小相位系统的动态输出反馈镇定.通过加积分器和非线性变换将系统化为一种标准形式,并基于标准形式的线性部分提出了动态补偿器的设计方法.然后根据得到的中心流形的表达式和稳定性定理,在零动态流形为一维时,证明了闭环系统的渐近稳定性,最后给出了一个零动态不具有齐次渐近稳定性但仍能动态输出反馈镇定的非线性最小相位系统的例子.     

一类具有不确定性的非线性相似组合系统的鲁棒镇定

描述了两个控制系统间的相似性概念,讨论了一类具有不确定性的非线性相似组合系统的鲁棒镇定问题.结果表明,作者构造的控制器具有结构相似性.相似结构确实可以简化组合系统鲁棒镇定的判据.这说明,在一定程度上,具有相似结构的组合系统其相似结构具有稳固系统的特性.     

A NOTE ON ROBUST STABILIZATION OF FEEDBACK LINEARIZABLE SYSTEMS

The problem of robust stabilization of nonlinear systems with feedback linearizable nominal part and norm-bounded nonlinear uncertainties is investigated. Necessary and sufficient conditions are obtained for robust stabilization of such systems. A design procedure is developed which combines feedback linearization technique and quadratic stabilization via linear feedback to achieve robust global asymptotic stability. © 1997 by John Wiley & Sons, Ltd.     

混合不确定性系统的鲁棒镇定及性能设计

采用双回路控制方法讨论具有混合不确定性系统的鲁棒镇定及性能设计问题，其内环控制器可改善对象特性，从而使整个双回路闭环系统具有鲁棒稳定性．     

奇异系统的输出稳定化通过一般状态反馈的可解性

讨论了奇异系统的输出稳定化问题，得到了在初始值为容许且不保证闭环正则的情形下，通过一般状态反馈求解此问题的充要条件及计算步骤     

MODEL‐REFERENCE OUTPUT‐FEEDBACK SLIDING MODE CONTROLLER FOR A CLASS OF MULTIVARIABLE NONLINEAR SYSTEMS

This paper proposes an output‐feedback sliding mode control design for a class of uncertain multivariable plants with nonlinear disturbances. The approach used here is based on the control parameterization employed in model‐reference adaptive control. The disturbances are allowed to be unmatched and to depend not only on the plant output but also on its unmeas‐urable state. A less restrictive condition on the uncertainty of the high frequency gain matrix is also obtained.     

FEEDBACK STABILIZATION OF NONHOLONOMIC CONTROL SYSTEMS WITH DRIFT

This paper presents a differential geometric approach for feedback stabilization of nonholonomic control systems with drift and its applicability is tested on two different systems possessing different algebraic structures: a system with six state variables and three controls, and a knife edge example. The approach is universal in the sense that it is independent of the vector fields determining the motion of the system, or of the choice of a Lyapunov function. The proposed feedback law is as a composition of a standard stabilizing feedback control for a Lie bracket extension of the original system and a periodic continuation of a specific solution to an open loop control problem stated for an abstract equation on a Lie group, an equation which describes the evolution of flows of both the original and extended systems. The open loop problem is solved as a trajectory interception problem in logarithmic coordinates of flows.