鲁棒镇定区间系统族的一个充分条件

讨论了区间系统族的鲁棒镇定问题,给出存在控制器鲁棒镇定区间系统族的一个充分条 件,并且当这个条件成立时,得到了鲁棒镇定区间系统族的控制器的参数化公式.     

一类参数不确定性系统的鲁棒控制

讨论了带有分母多项式摄动的参数不确定性系统的鲁棒镇定问题,给出了这类参数 不确定性系统存在鲁棒控制器的一个充分条件,并且当这个条件被满足时,得到了部分鲁棒 控制器的一个参数化公式.     

一类结构不确定性的离散时滞大系统的分散镇定

研究了一类离散时滞大系统的时滞相关鲁棒分散镇定问题, 系统的不确定与标称系统具有结构相似性. 通过构造性的差分格式, 将时滞相关鲁棒分散镇定控制器的存在条件转化为一列线性矩阵不等式的可行解问题. 提出了控制时滞及控制器的时滞鲁棒性概念, 在获得分散镇定控制器的同时给出了鲁棒时滞上界的求解, 因此比现有文献的结果更具有实际应用价值.     

鲁棒严格正实镇定的顶点结果

本文主要研究了区间系统的鲁棒严格正实镇定问题。文中首先给出了系统严格正实镇定的充分条件。然后分析了该条件的可计算性并对一类区间分母系统获得了采用一阶控制器时鲁棒严格正实镇定的顶点结果，使得控制器设计大为简化。     

执行器失效不确定时滞系统的指定衰减度鲁棒可靠控制

针对一类含有时变时滞的不确定参数线性系统,研究了在执行器发生故障情况下的鲁棒可靠控制器设计问题.系统中的参数不确定性满足广义匹配条件,时变时滞的大小及其变化率有界,并假设故障执行器元件的输出为零.经过适当的模型变换,将原系统的鲁棒指数镇定问题转化为另一个等价系统的鲁棒镇定问题.根据Lyapunov稳定性理论和线性矩阵不等式(LMI)方法,分别给出了鲁棒可靠控制器存在的时滞无关和时滞相关充分条件.仿真结果表明了该控制器设计方法的有效性.     

不确定时滞系统无记忆鲁棒镇定控制

本文研究了一类状态和控制同时存在滞后的线性时变不确定时滞系统的鲁棒镇定控制问题，针对所有容许的时变未知且有界的不确定性，得到了确保闭环系统二次稳定的充分条件。文中进一步把不确定时滞系统的二次镇定控制器设计问题等价为线性时不变系统的状态反馈标准Ｈ∞控制问题，并由此得到鲁棒镇定控制器综合设计方法。     

含参数不确定性系统的鲁棒性能设计

讨论含有参数不确定性系统的鲁棒性能设计问题。首先将该问题转化为一个多项式簇的鲁棒稳定性问题，从而得到鲁棒性能控制器应满足的频域充要条件，然后通过一个双回路控制器的设计将鲁棒镇定和鲁棒性能设计分两步进行，使设计条理化、简单化。     

具有非线性扰动多时滞系统鲁棒稳定性分析与分散鲁棒控制

研究一类非线性参数扰动满足范数有界条件时多重时滞系统的鲁棒稳定性及其分散鲁棒控制。首先利用Lyapunov函数方法分析系统的鲁棒稳定性,获得一种新的稳定性条件,然后利用标量Lyapunov方程方法讨论系统指数稳定的条件,通过对系统采取分散反馈控制,进一步得到系统可鲁棒镇定和可指数镇定的条件。     

具有输入饱和的非线性关联大系统的分散控制

考虑了一类具有输入饱和的不确定非线性关联大系统的分散输出反馈鲁棒镇定问题,利用Riccati方程的方法和矩阵的Moore-Penrose逆给出了这类系统的一种分散输出反馈鲁棒镇定控制器的设计方法.同时,考虑了一类具有输入饱和的不确定非线性相似关联大系统,利用相似系统的结构特点,简化了分散输出反馈鲁棒镇定的条件.     

同时镇定及鲁棒控制器存在条件

在保证闭环系统稳定的前提下,将被控对象看成控制器,控制器看成被控对象。从集合的角度研究了镇定区间对象族的控制器存在条件和设计方法,利用值集的概念和Youla参数化结果给出了镇定区间对象族控制器存在的充分条件．在强约束条件下,得到了控制器存在的充要条件．最后给出了鲁棒镇定控制器的设计方法．     

不确定性时滞系统基于观测器的鲁棒镇定

研究一类不确定性时滞系统的鲁棒镇定问题.当系统既有状态时滞又有控制输入时 滞,而且系统的状态和控制输入均含有不确定性时,假设不确定性满足具有一定物理意义的 匹配条件,得到了系统可由基于观测器的状态反馈鲁棒镇定的充分条件,并给出了观测器和 反馈控制器的设计步骤.该方法仅需求解两个黎卡提不等式.     

Peak-to-peak filtering for periodic piecewise linear polytopic systems

In this paper, the robust peak-to-peak filtering problem for periodic piecewise systems with polytopic uncertainties is investigated. Attention is focused on designing of robust peak-to-peak filters that guarantee the robust asymptotic stability of periodic piecewise filtering error system and satisfy a prescribed peak-to-peak disturbance attenuation level for all admissible uncertainties. A sufficient condition is proposed for robust stability and peak-to-peak performance by employing the constructed time-varying Lyapunov function. Two design approaches based on the Lyapunov function with parameter-dependent matrices and parameter-independent matrices are utilised to solve this problem. An algorithm is proposed to compute the periodic filter parameters governed by non-convex feasibility conditions. Two numerical examples are presented to demonstrate the effectiveness of the proposed techniques.     

Robust iterative learning control for systems with norm‐bounded uncertainties

A new robust iterative learning control scheme is presented for state tracking control of nonlinear MIMO systems. The main characteristic of the proposed controller lies in its ability to deal with unstructured uncertainties that are norm‐bounded but not globally or locally Lipschitz continuous as usual. The classical resetting condition of iterative learning control is removed and replaced with more practical alignment condition. The class of systems to be considered is further extended to more general scenarios, in which input distribution uncertainties are included. In the end, an illustrative example is presented to demonstrate the efficacy of the proposed control scheme. Copyright © 2015 John Wiley & Sons, Ltd.     

Robust Controllability of T–S Fuzzy-Model-Based Control Systems With Parametric Uncertainties

The robust controllability problem for the Takagi–Sugeno (T–S) fuzzy-model-based control systems is studied in this paper. Under the assumption that the nominal T–S fuzzy-model-based control systems are locally controllable (i.e., each fuzzy rule of the nominal T–S fuzzy-model-based control systems has a full row rank for its controllability matrix), a sufficient condition is proposed to preserve the assumed property when the parameter uncertainties are added into the nominal T–S fuzzy-model-based control systems. The proposed sufficient condition can provide the explicit relationship of the bounds on parameter uncertainties to preserve the assumed property. Besides, a robustly global controllability condition and the related robustly global stabilizability condition of the uncertain T–S fuzzy-model-based control systems are also presented in this paper. A nonlinear mass–spring–damper mechanical system with parameter uncertainties is given as an example to illustrate the application of the proposed sufficient conditions.      

Robust Stability For Uncertain Discrete Singular Systems With State Delay

A computationally simple stability condition for discrete singular systems with state delay is presented in this paper. Based on this, a robust stability result for such systems with structured parametric uncertainties is given. This condition ensures that, for all admissible uncertainties, the system under consideration is regular, causal and stable. Then D‐stability results for discrete singular delay systems are obtained. All the proposed conditions are easy to test.     

Robust H/sub /spl infin// control for uncertain discrete-time-delay fuzzy systems via output feedback controllers

This work investigates the problem of robust output feedback H/sub /spl infin// control for a class of uncertain discrete-time fuzzy systems with time delays. The state-space Takagi-Sugeno fuzzy model with time delays and norm-bounded parameter uncertainties is adopted. The purpose is the design of a full-order fuzzy dynamic output feedback controller which ensures the robust asymptotic stability of the closed-loop system and guarantees an H/sub /spl infin// norm bound constraint on disturbance attenuation for all admissible uncertainties. In terms of linear matrix inequalities (LMIs), a sufficient condition for the solvability of this problem is presented. Explicit expressions of a desired output feedback controller are proposed when the given LMIs are feasible. The effectiveness and the applicability of the proposed design approach are demonstrated by applying this to the problem of robust H/sub /spl infin// control for a class of uncertain nonlinear discrete delay systems.     

Robust D stabilization of singular systems with polytopic uncertainties

The robust D stabilization problem is considered for singular systems with polytopic uncertainties in this paper. Both the derivative matrix E and the state matrix A are with uncertainties, which were not considered before. First, with the introduction of some free matrices, a necessary and sufficient condition for the singular system to be D stable is proposed, based on which, the robust D stable problem is solved, and a sufficient condition for the closed system to be robust D stabilizable is obtained. The desired state feedback controller is given in an explicit expression. Numerical examples show the efficiency of the proposed approach.     

Robust V stabilization of singular systems with polytopic uncertainties

The robust D stabilization problem is considered for singular systems with polytopic uncertainties in this paper. Both the derivative matrix E and the state matrix A are with uncertainties, which were not considered before. First, with the introduction of some free matrices, a necessary and sufficient condition for the singular system to be D stable is proposed, based on which, the robust D stable problem is solved, and a sufficient condition for the closed system to be robust D stabilizable is obtained. The desired state feedback controller is given in an explicit expression. Numerical examples show the efficiency of the proposed approach.     

参数不确定统一混沌系统鲁棒最优控制

针对含有参数不确定性的统一混沌系统,基于鲁棒最优控制理论,提出了一种简单的线性状态反馈控制策略.该策略给出了系统渐进稳定的充分条件,并可以通过求解线性矩阵不等式(LMI),快速有效地求得系统反馈的控制增益,利用Lyapunov方法证明了闭环系统的稳定性.仿真结果验证了所提出的控制策略的有效性.     

Non-monotonic robust H2 fuzzy observer-based control for discrete time nonlinear systems with parametric uncertainties

A non-monotonic Lyapunov function (NMLF) is deployed to design a robust H₂ fuzzy observer-based control problem for discrete-time nonlinear systems in the presence of parametric uncertainties. The uncertain nonlinear system is presented as a Takagi and Sugeno (T–S) fuzzy model with norm-bounded uncertainties. The states of the fuzzy system are estimated by a fuzzy observer and the control design is established based on a parallel distributed compensation scheme. In order to derive a sufficient condition to establish the global asymptotic stability of the proposed closed-loop fuzzy system, an NMLF is adopted and an upper bound on the quadratic cost function is provided. The existence of a robust H₂ fuzzy observer-based controller is expressed as a sufficient condition in the form of linear matrix inequalities (LMIs) and a sub-optimal fuzzy observer-based controller in the sense of cost bound minimization is obtained by utilising the aforementioned LMI optimisation techniques. Finally, the effectiveness of the proposed scheme is shown through an example.