不确定离散模糊时滞系统的时滞相关H∞控制

研究了不确定离散T-S模糊时滞系统的稳定性分析与H∞控制问题．通过构造适当的Lyapunov泛函,给出了系统的时滞相关稳定新判据．进而利用线性矩阵不等式方法,研究了H∞模糊状态反馈控制器存在的充分条件,并提出控制器优化设计的迭代算法．     

不确定离散模糊时滞系统的时滞相关H∞控制

研究了不确定离散T-S模糊时滞系统的稳定性分析与H∞控制问题．通过构造适当的Lyapunov泛函,给出了系统的时滞相关稳定新判据．进而利用线性矩阵不等式方法,研究了H∞模糊状态反馈控制器存在的充分条件,并提出控制器优化设计的迭代算法．     

基于H∞控制的时滞系统故障诊断

应用H∞控制技术,探讨具有不确定性输入以及输入时滞系统的故障诊断（FD）问题.该文提出的算法能够诊断时滞系统的执行器故障和传感器故障.首先介绍了时滞系统的H∞控制技术,给出了时滞系统H∞控制器存在的充要条件.然后考虑含有故障的时滞系统,设计了故障诊断滤波器,将故障诊断滤波器与原系统组成增广系统,增广系统中包含时滞系统的执行器故障和传感器故障.最后,应用H∞控制技术,对增广系统设计故障诊断系统,能够诊断出时滞系统的执行器故障和传感器故障.     

线性时滞系统窗口H∞频域分析

在实际控制系统中,常常需要关注局部频段下的性能指标,而现有的频率加权方法缺乏针对性.由于时滞现象的普遍性及时滞条件下频域分析的复杂性,需要进一步给出时滞系统在局部频段下的H∞性能分析方法.为研究线性时滞系统在局部频段下的性能,基于广义Kalman-Yakubovich-Popov引理及窗口频域H∞范数的概念,给出了线性时滞系统的广义界实定理.针对不同频率范围,给出适用于不同频率条件的频域分析线性矩阵不等式判据.最后通过仿真实例,表明窗口频域分析比传统的全频段H∞分析具有针对性和有效性.     

基于模糊Lyapunov函数的离散模糊时滞系统H∞控制

研究一类离散Takagi-Sugeno（T-S）模糊时滞系统的稳定性分析和H∞控制器设计问题.通过构造适当的模糊Lyapunov函数,给出一种新型的基于线性矩阵不等式（LMI）的时滞相关稳定性充分条件,该条件比以往结果具有更小的保守性;在此基础上,提出了H∞模糊状态反馈控制器的设计方法.仿真结果表明了所提方法的有效性.     

广义时滞系统的时滞相关型H∞控制

研究了广义时滞系统的时滞相关型H∞控制问题.利用一个新构造的增广一离散化李亚普诺夫泛函并结合自由权矩阵方法,给出了使得系统正则、无脉冲、稳定且具有给定H∞性能界的时滞相关型有界实引理(BRL).在所得BRL基础上,得到了系统H∞状态反馈控制律的一个直接的设计方法.所给结果均以严格线性矩阵不等式( LMI)表示.数值实例表明了结果的有效性和较小保守性.     

时变不确定奇异时滞系统的时滞相关H∞控制

研究一类含有时变时滞的不确定奇异系统的H∞控制问题,采用Lyapunov泛函方法和线性矩阵不等式（LMI）工具,给出闭环系统正则、渐近稳定且具有范数界的时滞相关充分条件;通过求解相应的线性矩阵不等式,得到奇异系统的H∞控制律。与已有结论相比,该方法无需模型变换。数值算例说明该方法的有效性。     

应用线性矩阵不等式解决时滞系统控制问题

介绍了应用线性矩阵不等式（LMI）解决一类时滞系统H∞控制问题,给出了基于Lyapunov第二法的H∞稳定条件,通过求解锥补线性化问题,得到相应的控制器,使得闭环系统稳定且满足H∞性能指标.并通过实例给出了仿真结果.     

线性时滞系统依赖于时滞的H∞状态反馈控制

对具有纯滞后输入的线性时滞系统,在系统的状态时滞与控制输入时滞不同时,研 究了依赖时滞的H∞状态反馈控制器设计问题,其控制器存在的充分条件由一个线性矩阵不 等式(LMI)的形式给出,并给出了相应的H∞控制器的综合设计方法.     

大系统关联时滞分散鲁棒H∞控制

研究了一类关联时滞系统的分散鲁棒H∞控制问题,其中时滞是时变的。首先,设计了分散状态反馈H∞控制器,引入一种积分不等式方法,结合Lyapunov-Krasovskii泛函方法、积分矩阵不等式技巧和锥补法(CCL)导出了此类系统的关联时滞分散H∞控制的非线性矩阵不等式（NMI）和线性矩阵不等式（LMI）充分条件。接着,将结果扩展到分散输出反馈中。最后,数值例子说明了方法的有效性。     

Stability analysis of a general family of nonlinear positive discrete time-delay systems

In this paper, we propose a new approach to analyse the stability of a general family of nonlinear positive discrete time-delay systems. First, we introduce a new class of nonlinear positive discrete time-delay systems, which generalises some existing discrete time-delay systems. Second, through a new technique that relies on the comparison and mathematical induction method, we establish explicit criteria for stability and instability of the systems. Three numerical examples are given to illustrate the feasibility of the obtained results.     

Frequency-domain stability criteria for SISO and MIMO nonlinear feedback systems with constant and variable time-delays

New frequency-domain criteria are proposed for the $L_2$-stability of both nonlinear single-input-single-output (SISO) and nonlinear multiple-input-multiple-output (MIMO) feedback systems, described by nonlinear integral equations. For SISO systems, the feedback block is a constant scalar gain in product with a linear combination of first-and-third-quadrant scalar nonlinearities (FATQNs) with time-delay argument functions; and, for MIMO systems, it is a constant matrix gain in product with a linear combination of vector FATQNs also with time-delay argument functions. In both the cases, the delay function in the arguments of the nonlinearities may be, in general, i) zero, ii) a constant, iii) variable-time and iv) fixed-history (only for SISO systems). The stability criteria are derived from certain recently introduced algebraic inequalities concerning the scalar and vector nonlinearities, and involve the causal+anticausal O''Shea-Zames-Falb multiplier function (scalar for SISO systems and matrix for MIMO systems). Its time-domain $L_1$-norm is constrained by the coefficients and characteristic parameters (CPs) of the nonlinearities and, in the case of the time-varying delay, by its rate of variation also. The stability criteria, which are independent of Lyapunov-Krasovskii or Lyapunov-Razumikhin functions and do not seem to be derivable by invoking linear matrix inequalities, seem to be the first of their kind. Two numerical examples for each of SISO and MIMO systems illustrate the criteria.     

Robust stability of homogeneous large-scale bilinear systems with time delays and uncertainties

This paper addresses the problem of stability analysis for homogeneous large-scale uncertain bilinear time-delay systems subjected to constrained inputs. Both nonlinear uncertainties and interval systems are discussed. Several delay-independent criteria are presented to guarantee the asymptotic stability of the overall systems. The main feature of the presented criteria is that although the Lyapunov stability theorem is used, they do not involve any Lyapunov equations that may be unsolvable. Three illustrative numerical examples are presented to verify the effectiveness of the proposed stability criteria.     

Robust stability criteria for dynamical systems including delayedperturbations

Considers the problem of robust stability of uncertain time-delay dynamical systems. A new robust stability criteria for linear dynamical systems subject to delayed time-varying and nonlinear perturbations is derived. The results obtained in this note are less conservative than the ones reported so far in the literature. Some analytical methods are employed to investigate the bound on the perturbations so that the systems are stable. A numerical example is given to demonstrate the utilization of the authors' results     

一类新的Takagi-Sugeno模糊时滞系统的稳定性准则

本文提出一种新的时滞划分方法—变时滞划分法,以解决连续延时Takagi-Sugeno模糊系统的稳定性和镇定性问题.不同于已有的文献,用可变参数将时变时滞区间[0,d(t)]划分为若干个可变子区间,并得出模糊时滞系统的新的时滞相关稳定性准则.本文提出的新方法能充分利用时滞子区间的内部信息,因此新的时滞相关稳定性准则比以往结果具有更小的保守性.基于Lyapunov稳定性理论,以线性矩阵不等式形式给出T--S模糊系统的新的时滞相关稳定性准则,并将稳定性和镇定性研究结果扩展到具有不确定参数的T--S模糊系统.仿真实例证明了本文方法降低保守性的有效性.     

Robust analysis of nonlinear discrete systems with multiple time delays

In this paper, we present the stability criteria, sufficient conditions that guarantee the robust stability of linear structured or unstructured variation of discrete time-delay systems subjected to the given bounds of nonlinear function. Both single and composite nonlinear discrete systems with multiple time delays are considered and each of these results is expressed by a succinct scalar inequality and independent of delay time.     

不确定时滞离散非线性系统的鲁棒耗散滤波

研究了一类带参数不确定性和非线性动态的离散时滞系统的鲁棒耗散滤波问题.所给系统中的不确定项是时变未知且范数有界.基于Lyapunov稳定性方法,先对参数已知而带有非线性动态的时滞离散系统,给出渐近稳定判据,然后讨论鲁棒耗散滤波器的存在条件及设计方法.在此基础上进一步考虑参数不确定性情形,将鲁棒耗散滤波器问题转化为参数确定的情况.从而将鲁棒耗散滤波器的设计问题转换为线性矩阵不等式的求解问题.最后给出仿真例子验证所得结果的有效性.     

一类非线性广义系统的时滞相关耗散控制

针对一类带有非线性摄动的广义时滞系统,研究了时滞相关的鲁棒耗散问题.讨论了此类非线性广义时滞系统的鲁棒耗散性.同时对此类非线性广义时滞系统的二次稳定性进行了研究,分别用线性矩阵不等式（LMI）的方法给出了充分条件,也给出了时滞相关的鲁棒耗散的时滞上界.并且,给出了时滞相关的鲁棒耗散的状态反馈控制器.最后,通过例子验证了定理的可行性.     

线性定常时滞系统全时滞渐近稳定的充分代数判据

本文探讨了线性定常时滞系统全时滞渐近稳定性问题,并给出了简单实用的稳定性充分 代数判据.     

Improved Stability Criteria for Discrete-time Delay Systems via Novel Summation Inequalities

This paper is concerned with the stability analysis of linear discrete time-delay systems. New discrete inequalities for single summation and double summation are presented to estimate summation terms in the forward difference of Lyapunov-Krasovskii functional (LKF), which are more general than some commonly used summation inequalities. Through the construction of an augmented LKF, improved delay-dependent stability criteria for discrete time-delay systems are established. Based on this, a time-delayed controller is derived for linear discrete time-delay systems. Finally, the advantages of the proposed criteria are revealed from the solutions of the numerical examples.