任意反馈结构下的分散状态反馈镇定

给定一个系统,在完全分散的状态反馈下,系统可能不能被镇定,这就要求改变系统的反 馈结构.本文首先推导出在任意反馈结构下,分散状态反馈可镇定的条件,然后给出一个简单 而有效的方法,用以修改原有的反馈结构,使得系统能被镇定.     

基于状态反馈的一类非线性系统动态输出反馈镇定

针对一类具有线性不可测量状态的非线性系统,基于状态反馈稳定控制器,利用不变流形和滑模变结构控制技术设计了动态输出反馈镇定控制器.这类控制器的结构类似于系统的状态反馈稳定控制器,在较简单的假定条件下,能够保证被控系统的状态得到渐近镇定.仿真算例表明该动态输出反馈控制器具有较强的镇定能力.     

用局部状态反馈的分散化镇定

本文考虑一般关联大系统的分散镇定问题。通过调节系统的二次型目标函数,我们推导出一种系统的用局部状态反馈的分散镇定方法。这种方法基于子系统模型求解,简单,有效,并用一个数字例子验证了这一方法。     

具有时滞互联项的线性不确定系统的分散反馈镇定

文章研究了一类互联项具有时滞的不确定组合大系统,基于系统的状态反馈给出了系统可分散反馈镇定的控制规律。利用线性矩阵不等式给出了系统可分散反馈镇定的充分条件,最后用实例验证了所得结论的正确性。     

非线性大系统的分散输出反馈半全局鲁棒镇定

从半全局镇定角度研究非线性大系统的分散输出反馈鲁棒镇定问题．对一类满足新型增长条件的非线性大系统, 给出了分散输出反馈半全局鲁棒镇定控制器的设计方法．对任意给定状态空间的紧子集, 可经此方法设计分散输出反馈控制器, 使受控大系统在原点是渐近稳定的同时吸引域包含指定的紧子集．     

带传输滞后的线性离散系统的状态反馈镇定

针对存在传输滞后的线性离散系统的状态反馈镇定问题,给出了系统可镇定的一个内部限制条件.为克服这一限制条件,提出了两种方法:一种是充分利用滞后状态的信息,另一种是设计带有递推动态的状态反馈控制器.研究结果表明,若系统在没有传输滞后时能通过状态反馈被镇定,则存在传输滞后时一定也能通过设计新的控制器使系统被镇定.     

线性多级动态结构大系统的反馈镇定

本文研究一类由Ｎ个子系统组成的具有多级动态结构线性大系统的多级反馈镇定问题，这类系统的多级反馈可镇定性与相应地导出系统分散反馈可镇定性等价。利用这种等价性以及系统本身的结构特征，给出了这类大系统可多级反馈镇定的充分条件。对于给定系统，应用本文的结论判别其多级反馈可镇定性是比较容易的。     

分数阶线性定常系统的状态反馈镇定

研究了在分数阶受控系统中稳定性的问题。假定分数阶系统是在线性定常的情况下,利用状态反馈的方法,构造状态反馈矩阵以实现对系统的稳定性控制;给出了分数阶系统由状态反馈镇定的条件及其证明,并给出了状态反馈镇定的综合算法。仿真实例证明了采用状态反馈实现系统镇定的可行性和有效性。     

具有输入饱和的组合系统的分散控制

研究了一类具有饱和输入的组合系统的分散可镇定问题. 运用M-矩阵方法, 通过线性分散状态反馈得出具有饱和输入组合系统的可镇定的充分条件. 对于具有对称结构的组合系统, 给出了更为简单的镇定条件.     

离散时滞切换系统的无记忆状态反馈镇定

针对一类子系统为离散时滞系统的切换系统,研究了稳定性与无记忆状态反馈镇定问题．采用多李雅普诺夫函数法,首先以线性矩阵不等式形式给出了在任意切换信号作用下离散时滞切换系统渐进稳定的一个充分性条件;然后给出了系统无记忆状态反馈镇定的控制器设计方案,并将结果推广到不确定离散时滞切换系统;最后用仿真算例验证了所提出设计方案的可行性。     

Time-varying feedback laws for decentralized control

Decentralized control schemes are considered for time-invariant, finite dimensional, linear systems with know state equations. It is assumed that the systems are reachable and observable at a fictitious centralized control station, and that there is strong connectivity between the decentralized control stations via the system where necessary. It is shown that whether or not there are decentralized fixed modes in the open-loop system, periodically varying feedback gains at all but one of the control stations permit the remaining control station to observe and control the system given knowledge of the control laws implemented at the other control stations. Certain time-invariant systems which cannot be stabilized by decentralized time-invariant controllers, namely those with unstable decentralized fixed modes, can thus be stabilized by decentralized time-varying controllers.     

关于多通道系统的动太递阶镇定

研究镇定多通道系统的一种新策略--动态递阶控制.对线性时不变确定型通道强关 联系统,得到了在给定信息结构下采用动态递阶控制可任置极点(镇定)的一个充分必要条 件,解决了分散循环系统采用动态递阶控制时的最小信息结构问题,并讨论了动态协同控铋 器的最小阶数,最后给出了一个数值例子.     

Optimality of decentralized control for large-scale systems

A decentralized control scheme is given for the stabilization of large-scale linear systems composed of a number of controllable subsystems. A class of interconnection structures among subsystems is defined for which the overall system can always be stabilized by local state feedback which is optimal for a quadratic performance index. The resulting closed-loop system has robust stability properties against a wide range of variations in open-loop dynamics. Optimality of the decentralized control law is preserved for a modified performance index under perturbations in interconnections such that the strength of coupling does not increase. The class of decentrally stabilizable large-scale systems presented in this paper is the largest such class hitherto described by the structure of interconnections.     

不确定相似组合系统的分散自适应输出反馈控制

本文讨论了不确定组合大系统的分散自适应输 出反馈控制问题,不确定项满足通常的匹配条件．针对不确定项界未知的情形,通过设计自 适应输出反馈控制器,使系统渐近稳定．仿真结果表明本文的设计方法是有效的．     

Decentralized observer-based stabilization for a class of interconnected systems

A decentralized output feedback law for a class of interconnected systems is described. The proposed output feedback scheme is based on the decentralized reconstruction of the unmeasurable subsystem state variables and interacting state variables. A sufficient condition is given for the overall system to be stabilizable by using the proposed output feedback control law.     

FAULT TOLERANT CONTROL OF FLEXIBLE SMART STRUCTURES USING ROBUST DECENTRALIZED FAST OUTPUT SAMPLING FEEDBACK TECHNIQUE

This paper presents the modeling, design and simulation of a Robust Decentralized Fast Output Sampling (RDFOS) feedback controller for the vibration control of a smart structure (flexible cantilever beam) when there is actuator failure. The beam is divided into 8 finite elements and the sensors / actuators are placed at finite element positions 2, 4, 6, and 8 as collocated pairs. The smart structure is modeled using the concepts of piezoelectric theory, Euler‐Bernoulli beam theory, Finite Element Method (FEM) techniques and the state space techniques. Four multi‐variable state‐space models of the smart structure plant are obtained when there is a failure of one of the four actuators to function. The effect of failure of one of the piezo actuators to function during the vibration of the beam is observed. The tip displacements, open and closed loop responses with and without the controller are observed. For all of these models, a common stabilizing state feedback gain F is obtained. A robust decentralized fast output sampling feedback gain L which realizes this state feedback gain is obtained using the LMI approach. In this designed control law, the control inputs to each actuator of the multi‐model representation of the smart structure is a function of the output of that corresponding sensor only and the gain matrix has got all off‐diagonal terms zero and this makes the control design a robust decentralized one. Then, the performance of the designed smart system is evaluated for Active Vibration Control (AVC). The robust decentralized FOS controller obtained by the designed method requires only constant gains and hence may be easier to implement in real time.     

参数不确定广义大系统的保性能分散控制

对一类范数有界时不变参数不确定的连续广义大系统和一个二次型性能指标,研究了其保性能分散控制问题.目的是设计一状态反馈分散控制器,使得对所有容许的不确定性,闭环系统不仅是鲁棒稳定的,而且性能指标有一上界.应用线性矩阵不等式方法,给出了一个用线性矩阵不等式表达的保性能分散控制器存在的充分条件;在此条件可解时,给出了保性能分散控制律的表达式.最后,举例说明了该方法的应用.     

Controllability under decentralized information structure

In this paper, the controllability under decentralized information structure is studied for linear continuous-time systems. It is defined as follows. A system is controllable under the decentralized information structure if there exists a decentralized control law which transfers any unknown initial state to the origin in a finite time interval Necessary and sufficient conditions of the controllability under the decentralized information structure are given. It is also shown that the controllability under the decentralized information structure is a necessary condition of the pole-assignability with a local dynamic feedback control law.