一类多时变时滞T-S模糊广义系统的容许控制

研究了一类具有多时变时滞的T-S模糊广义系统的容许控制问题。首先,给出了多时变时滞的T-S模糊广义系统数学模型,并且利用Lyapunov稳定性分析方法,得到了多时变时滞的T-S模糊广义系统的容许的一个充分条件,所得的结果对时变时滞的变化率没有限制。该充分条件可以通过严格线性矩阵不等式来求解。然后基于所给出的容许性定理,提出了状态反馈控制器的设计方法.最后,使用算例说明了所给方法的可行性和有效性。     

基于模糊Lyapunov函数方法的模糊广义系统H∞控制

研究一类T-S模糊广义系统的容许性条件和H∞控制问题. 首先将原系统表示成增广系统, 进而基于新的模糊Lyapunov函数和模糊控制器得到容许性条件. 所得开环容许条件不要求子系统是容许的; 闭环容许条件中不含有控制输入矩阵与控制增益矩阵的乘积项. 对于H∞控制问题, 利用隶属度函数的性质对H∞控制条件进行了放宽, 并得到了改进的严格线性矩阵不等式(LMI)形式的H∞控制条件. 数值算例表明所得结论较已有文献具有较小的保守性.     

“分数阶广义系统容许性的充分必要条件”一文评论

《自动化学报》39卷12期的"分数阶奇异系统容许性的充分必要条件"得到了基于线性矩阵不等式的分数阶广义系统容许性充分必要条件.本文给出一个数值反例表明文献[1]中定理1的充分条件结论并不成立, 必要条件也不准确.最后, 给出了修改正确的分数阶广义系统容许性充分必要条件.相比于文献[1]的定理1, 改进后充要条件没有保守性并去除了原文中分数阶广义系统正则性的限制要求.     

一般广义周期时变系统的H∞控制

针对一般广义周期时变系统的H∞控制问题,采用Lyapunov函数理论和线性矩阵不等式(LMI)相结合的分析方法,通过分析正常周期时变系统和一般广义周期时变系统允许的充分必要条件,得到了一般广义周期时变系统允许且满足H∞控制性能指标的充分必要条件.所得结论将广义系统H∞控制问题研究成果推广到一般广义周期时变系统的控制性能,奠定了广义时变系统H∞控制问题的研究基础.     

模糊离散广义系统的鲁棒容许条件:严格LMI方法

研究了T-S模糊离散广义系统的鲁棒容许性问题.对于开环标称系统,基于严格线性矩阵不等式(LMI)给出了容许性判别条件.进而基于此条件并引入新的矩阵变量,得到严格线性矩阵不等式形式的鲁棒控制器设计方案.使得通过反馈控制,闭环系统在不确定性范围内是正则、因果、稳定的.最后通过算例仿真验证方法的有效性.     

离散T-S模糊广义系统的H∞控制

研究了离散T-S模糊广义系统的H_∞控制问题. 首先引入辅助矩阵变量得到新的容许性条件, 解决了由于矩阵P的不定性, 无法运用Schur补引理处理非线性Lyapunov不等式的问题, 进而得到严格不等式表示的H_∞控制条件.基于模糊Lyapunov函数方法, 分别研究了状态反馈控制器、静态输出反馈控制器、动态输出反馈控制器的构造方法. 所得结论可推广到系统具有范数有界不确定性的情况. 最后通过算例验证方法的有效性.     

广义时变系统的鲁棒 H∞ 容错控制

对于一类广义时变不确定系统,在执行器故障情况下给出了系统具有容许性的充分条件,并设计反馈控制器使其满足给定的 H∞ 干扰衰减指标,使得系统在正常与故障情况下都具有容许性.最后给出数值算例来证明结论的有效性.     

基于动态补偿的矩形广义系统线性二次最优控制

考虑了基于动态补偿的矩形广义系统线性二次最优控制问题. 首先给出具有适当动态阶的补偿器,使得闭环系统正则、稳定、无脉冲(称为容许), 而且相关的矩阵不等式和Lyapunov方程解存在. 进一步二次性能指标可写成一个与该解和系统初值相关的表达式. 为了求解系统的最优控制问题, 将该Lyapunov方程转化为一个双线性矩阵不等式, 并给出了相应的路径跟踪算法以最小化二次性能指标, 进而得到最优补偿器. 最后, 通过数值算例说明本文方法的有效性和可行性.     

Lurie广义系统基于观测器的控制器设计

研究了Lurie广义系统基于状态观测器的控制器设计问题.通过使用Lyapunov稳定性理论,线性矩阵不等式方法,分别给出了状态反馈控制器和观测器的设计方法,并建立了分离原理,进而得到了基于观测器的控制器设计方法.所得结论对广义系统理论本身的发展和实际应用都有非常重要的意义.最后给出了仿真实例.     

广义时变系统的鲁棒H2/H∞滤波

研究一类广义时变系统的鲁棒H2/H∞滤波器的设计问题。 利用具有参数依赖的Lyapunov函数,结合线性矩阵不等式分别给出了使滤波误差系统容许且满足H∞性能约束的充分条件、使滤波误差系统容许且满足H2性能约束的充分条件以及使滤波误差系统容许且满足H2/H∞性能指标的充分条件。 基于该具有参数依赖Lyapunov函数的鲁棒H2/H∞性能准则推导出鲁棒H2/H∞滤波器存在的充分条件,并将滤波器的设计问题转化为线性矩阵不等式约束优化问题。 最后通过数值算例表明该方法的有效性。     

Robust admissibility and admissibilisation of uncertain discrete singular time-delay systems

This paper is concerned with the characterisation of robust admissibility and admissibilisation for uncertain discrete-time singular system with interval time-varying delay. Considering the norm-bounded uncertainty and the interval time-varying delay, a new comparison model is introduced to transform the original singular system into two connected subsystems. After this transformation, a singular system without uncertainty and delay can be handled by the Lyapunov–Krasovskii functional method. By virtue of the scaled small gain theorem, an admissibility condition of the original singular system is proposed in terms of linear matrix inequalities. Moreover, the problem of robust admissibilisation of uncertain discrete singular time-varying system is also studied by iterative linear matrix inequality algorithm with initial condition optimisation. Several numerical examples are used to illustrate that the results are less conservative than existing ones.     

New stability criteria of singular systems with time-varying delay via free-matrix-based integral inequality

This paper concerns the stability problem of singular systems with time-varying delay. First, the singular system with time-varying delay is transformed into the neutral system with time-varying delay. Second, a more proper Lyapunov–Krasovskii functional (LKF) is constructed by adding some integral terms to quadratic forms. Then, to obtain less conservative conditions, the free-matrix-based integral inequality is adopted to estimate the derivative of LKF. As a result, some delay-dependent stability criteria are given in terms of linear matrix inequalities. Finally, two numerical examples are provided to demonstrate the effectiveness and superiority of the proposed method.     

A new admissibility condition of discrete-time singular systems with time-varying delays

This paper gives a novel delay-dependent admissibility condition of discrete-time singular systems with time-varying delays. For convenience, the time-varying delay is assumed to be the sum of delay lower bound and the integral multiples of a constant delay. Specially, if the constant delay is of unit length, the delay is an interval-like time-varying delay. The proposed admissibility condition is presented and expressed in terms of linear matrix inequality (LMI) by Lyapunov approach. Generally, the uncertainty of time-varying delay would lead to conservatism. In this paper, this critical issue is tackled by accurately estimating the time-varying delay. Consequently, the proposed admissibility condition is less conservative than the existing results, which is demonstrated by a numerical example.     

不确定切换奇异时滞系统鲁棒指数容许性分析

讨论一类连续时间不确定切换奇异区间时变时滞系统的鲁棒指数容许性问题. 通过定义衰减率依赖李亚普诺夫函数并利用平均驻留时间法, 给出一个时滞区间依赖充分条件保证标称系统正则、无脉冲且均方指数稳定. 同时该准则也被推广至不确定系统. 本文获得的结论为连续时间切换奇异时滞系统的基本问题提供了一个解, 即识别切换信号使得切换奇异时滞系统正则、无脉冲且均方指数稳定. 数值例子说明本文结果的有效性.     

切换线性奇异系统输出反馈容许控制

The admissibility analysis and robust admissible control problem of the uncertain discrete- time switched linear singular (SLS) systems for arbitrary switching laws are investigated. Based on linear matrix inequalities, some sufficient conditions are given for: A) the existence of generalized common Lyapunov solution and the admissibility of the SLS systems for arbitrary switching laws, B) the existence of static output feedback control laws ensuring the admissibility of the closed-loop SLS systems for arbitrary switching laws and norm-bounded uncertainties.     

短时延广义网络控制系统的指数保性能控制

本文基于标称点方法,在短时变时延条件下,研究了广义网络控制系统的指数稳定保性能控制问题.基于李雅普诺夫稳定性判据和线性矩阵不等式技术,给出了使得系统能够指数稳定且满足二次型性能指标的状态反馈控制器存在的条件和设计方法.通过采用标称点方法,有效地解决了现有方法没有考虑网络诱导时延与系统保守性的关系且适用范围有限的问题,并通过算例验证了有效性.由于建模过程中充分考虑了系统的保守性,相比之下获得了更好的二次型性能指标值.     

Admissibility analysis of linear singular systems via a delta operator method

In this paper, the problem of admissibility analysis is investigated for linear singular systems through a delta operator method. The delta operator model of a linear singular continuous system is set up first for a special case and then generalised to the common case. It is shown that when the sampling period tends to zero, the delta operator model tends to the corresponding singular continuous system. In order to obtain the above delta operator model, we adopt a linear singular discrete model which contains the sampling period instead of the standard discrete one which contains no sampling period in the modeling process. The relation between the admissibility of the two singular discrete models is analysed and it is proved that the admissibility of one singular discrete model is equivalent to that of the other discrete model. Moreover, based on the relation between the discrete and delta operator models, some admissibility conditions are derived for linear singular delta operator systems. A numerical example is also provided to demonstrate the theoretical results in this paper.     

不确定广义线性时变系统的鲁棒稳定和二次稳定

针对不确定广义线性时变系统,采用矩阵不等式的分析方法,提出不确定广义线性时变系统鲁棒稳定和二次稳定的概念.建立该类系统的矩阵不等式,将该类系统的鲁棒控制问题转化为求解矩阵不等式问题,得到该类系统鲁棒稳定和二次稳定的充分必要条件,并给出一种状态反馈鲁棒镇定控制器的设计方法.最后,通过数值算例表明了所提出方法的可行性.     

分数阶奇异系统容许性的充分必要条件

探讨了阶数在（0,1）区间的分数阶奇异系统的容许性条件. 文中首先给出了正则性,无脉冲性和容许性的定义,然后给出了分数阶奇异系统容许性的充分必要条件,最后通过数值仿真的例子来说明我们给出的容许性条件.     

Less conservative robust stability criteria for uncertain discrete stochastic singular systems with time-varying delay

The problem of robust stabilisation for uncertain discrete singular systems with time-varying delay is discussed in this article. First, a new delay-distribution-dependent Lyapunov function is established. Then, sufficient conditions are proposed for guaranteeing that the uncertain discrete singular system with time-varying delay has the properties of regularity, causality and stability. Finally, a suitable robust state feedback controller is designed by linear matrix inequality. Numerical examples illustrate that the results derived from the proposed method are less conservative than the existing ones.