一类切换模糊时滞系统的状态反馈控制

针对切换模糊时滞系统,根据平行分布补偿算法,设计了模糊状态反馈控制器.使用切换技术及单Lyapunov函数和多Lyapunov函数方法,给出了这一类切换模糊时滞系统渐近稳定的充分条件及切换律.仿真结果表明了方法的有效性.     

切换线性时滞系统的稳定性判据

考虑了一类切换线性时滞系统的稳定性问题.基于Lyapunov函数方法和矩阵测度的概念,分别给出了切换系统时滞独立以及时滞依赖的渐近稳定性和指数稳定性判据,设计了相应的镇定切换律.最后,通过数值算例验证了所提算法的正确有效性.     

基于观测器的切换模糊时滞系统的反馈控制

针对状态不可测的切换模糊时滞系统, 根据平行分布补偿算法(PDC), 设计了切换模糊观测器和反馈控制器, 应用共同Lyapunov函数方法使观测误差系统在任意切换下渐近稳定, 应用多Lyapunov函数方法, 使系统状态在设计切换律下渐近稳定, 并给出了时滞相关的切换模糊系统渐近稳定的矩阵不等式条件. 仿真结果表明结论的有效性.     

一类不确定离散切换模糊时滞系统的鲁棒非脆弱控制

针对一类不确定离散切换模糊时滞系统,研究了在控制器增益存在摄动情况下的稳定性问题.利用切换技术和多Lyapunov函数方法,并以矩阵不等式形式给出了非脆弱状态反馈控制器存在的充分条件和切换律设计.最后通过数值仿真算例验证了设计方法的有效性和可行性.     

一类不确定切换模糊时滞系统的保性能控制

针对一类存在时滞的不确定切换模糊系统,研究系统的保性能控制问题.利用平行分布补偿算法(PDC)给出保性能控制器的设计方法,利用单Lyapunov函数方法和多Lyapunov函数方法,给出不确定切换模糊时滞系统保性能控制器存在的充分条件和切换律设计.使得闭环系统对所有允许的不确定,在所设计的控制器和切换律下实现保性能控制.仿真结果表明方法的有效性.     

一类时滞切换系统的输入-状态稳定性分析

利用多Lyapunov函数方法、驻留时间法和Gronwall-Bellman不等式研究了一类时滞切换系统的输入-状态稳定性分析问题．从系统输入-状态稳定定义出发,给出了使得一类时滞切换系统输入-状态稳定的充分条件．与已有的方法相比,无需同时满足构造输入-状态稳定控制Lyapunov函数和所有子系统都是输入-状态稳定的条件,为控制器的设计提供了便利．最后,通过算例仿真验证了所提出方法的可行性．     

一类带有时滞的不确定广义系统的切换渐近稳定性

研究了一类带有时滞的切换不确定广义系统的鲁棒渐近稳定问题. 利用Lyapunov稳定性定理和线性矩阵不等式(Linear matrix inequality, LMI)工具, 采用多Lyapunov函数技术, 在设定的切换律下, 得到切换不确定广义时滞系统鲁棒渐近稳定的时滞相关充分条件. 进一步, 建立了一个具有线性矩阵不等式约束的凸优化问题, 利用Matlab软件中的LMI工具箱求解, 得到保证切换广义系统鲁棒渐近稳定的最大可允许时滞上界. 最后示例表明了该方法的有效性.     

一类不确定切换模糊时滞系统的鲁棒控制

针对利用模糊T-S模型建模的切换模糊系统,考虑当系统同时存在不确定和时滞的情况下,研究系统的状态反馈控制问题.利用切换技术和多Lyapunov函数方法,给出状态反馈控制器存在的充分条件,相应结果以矩阵不等式形式给出,并给出切换律设计.利用平行分布补偿算法(PDC),给出切换模糊状态反馈控制器设计,使得闭环系统在所设计的控制器和切换律下,对所有允许的不确定具有鲁棒性.仿真结果表明方法的有效性.     

时滞切换系统稳定性分析与镇定-Lyapunov函数方法

利用Lyapunov函数方法克服“相空间”与“事件空间”之间的不一致,以考虑时滞切换系统稳定性的分析与综合.其一,对将多Lyapunov函数方法推广至时滞情形,由此给出子系统稳定性准则及切换序列的约束条件,使整个系统是指数稳定的.其二,对于不稳定的时滞子系统,提出了保证观测误差在任意切换作用下指数衰减的观测器设计方法,并构造出基于估计状态的切换序列,使状态变量指数收敛.     

不确定切换时滞非线性系统状态切换的指数稳定性

利用状态依赖控制策略对切换信号进行设计,使得一类参数不确定时滞非线性切换系统指数稳定且具有一定的??∞抗干扰性能。利用Lyapunov-Krasovskii (LK)函数方法,以线性矩阵不等式组的方式,给出了稳定切换律存在的充分条件,并且该系统是指数稳定的。通过引入自由矩阵并结合积分不等式技巧,得到了保守性较低的稳定性条件。仿真算例表明了所提出方法的有效性和较低的保守性。     

Exponential Stability of Switched Time-varying Delayed Neural Networks with All Modes Being Unstable

This paper aims to design an appropriate switching law to stabilize the switched neural networks with time-varying delays when all subsystems are unstable. By using the discretized Lyapunov function approach and the extended comparison principle for impulsive systems, the stability of switched delayed neural networks composed full of unstable subsystems is analyzed and a computable sufficient condition is derived in the framework of dwell time. The effectiveness of the proposed results is illustrated by a numerical example.     

Analysis of robust stability for switched systems with multiple time-delays

The sufficient conditions of delay-dependent exponential stability for switched systems and robust exponential stability for uncertain switched systems with two time-delays are presented by using average dwell time method and free-weighting matrix method.The interaction between different time-delays is considered.The sufficient conditions do not need that every subsystem is stable.The designed methods of the switching law are also given.The sufficient conditions are given in the form of linear matrix inequalities that can be solved easily.The result is proven to be valid by the simulation at last.     

Robust adaptive tracking control for a class of switched time-delay systems with application of vehicle roll dynamic control

The problems of stability and robust tracking control for a class of switched nonlinear systems with uncertain input and state delays are investigated in this study. In the presence of unknown functions and external disturbances, an adaptive fuzzy technique based on nonlinear disturbance observer is used to counteract the effects of external disturbances and approximate unknown functions. For this purpose, it is first assumed that a common Lyapunov function exists for the switched system, and then a new common Lyapunov–Krasovskii functional is built using the terms of the hypothetical common Lyapunov function. By employing this new function, the delay-dependent input-to-state stability (ISS) under an arbitrary switching signal is provided. The robust tracking control problem for this system is investigated next. Finally, to assure ISS and robust tracking performance, an adaptive control law is developed that ensures conditions of the aforementioned hypothetical common Lyapunov function. In addition, to demonstrate the efficiency of the proposed strategy, the aforesaid method is applied to a vehicle roll dynamic as well as a mass-spring system.     

Improved stability criterion and its applications in delayed controller design for discrete-time systems

This paper is concerned with the problem of delay-dependent stability analysis for discrete-time systems with interval-like time-varying delays and the problem of stabilization for discrete-time linear systems via time-delayed controllers. The first problem is solved by applying a novel Lyapunov functional, and an improved delay-dependent stability criterion is obtained in terms of a linear matrix inequality. Based on this, a sufficient condition for the solvability of the second problem is presented. The reduced conservatism of the proposed stability result is shown through a numerical example, while the applicability of the time-delayed controller design method is demonstrated by an inverted pendulum system.     

Fuzzy adaptive output feedback control for a class of switched non-triangular structure nonlinear systems with time-varying delays

This paper investigates an adaptive fuzzy output feedback control design problem for switched nonlinear system in non-triangular structure form. The discussed system contains unknown nonlinear dynamics, unmeasured states and unknown time-varying delays under a batch of switching signals. Fuzzy logic systems are utilised to learn unknown nonlinear dynamics and construct a fuzzy switched nonlinear observer. By combining the property of fuzzy basis function with Lyapunov–Krasovskii functional and the command filter, a novel observer-based fuzzy adaptive backstepping schematic design algorithm is presented. Furthermore, the stability of the closed-loop control system is proved via Lyapunov stability theory and average dwell time method. The simulation results are presented to verify the validity of the proposed control scheme.     

一类不确定切换奇异时滞系统的时滞依赖鲁棒镇定

针对一类不确定切换奇异时滞系统,对其鲁棒镇定问题进行了研究.首先利用多李亚普诺夫泛函方法和线性矩阵不等式工具,通过引入适当的自由权矩阵,在适当的切换律下,给出了基于严格线性矩阵不等式表示的标称自治切换奇异系统正则、无脉冲且渐近稳定的时滞依赖条件;然后基于此条件,通过设计相应的状态反馈子控制器,得到了保证闭环系统对所有允许的不确定性是正则、无脉冲且渐近稳定的时滞依赖条件,同时给出了子控制器的显示表达式.数值算例表明该方法的有效性.     

网络控制系统的最大允许时延界

提出确定多输入多输出网络控制系统的最大允许时延界的新方法. 由于网络诱导时延的分布特性, 整个多输入多输出网络控制系统实际上是一个多时延系统. 利用李雅普诺夫第二方法, 得到网络控制系统时延相关渐近稳定性判据. 最大允许时延界和输出反馈镇定控制器均可通过求解矩阵不等式(LMI)得到. 仿真比较说明了本文结果的正确性和可行性.     

Stability analysis and anti-windup design of switched systems with actuator saturation

The stability analysis and anti-windup design problem is investigated for two linear switched systems with saturating actuators by using the single Lyapunov function approach. Our purpose is to design a switching law and the anti-windup compensation gains such that the maximizing estimation of the domain of attraction is obtained for the closed-loop system in the presence of saturation. Firstly, some sufficient conditions of asymptotic stability are obtained under given anti-windup compensation gains based on the single Lyapunov function method. Then, the anti-windup compensation gains as design variables are presented by solving a convex optimization problem with linear matrix inequality (LMI) constraints. Two numerical examples are given to show the effectiveness of the proposed method.     

Relaxed delay-dependent stabilization criteria for discrete-time fuzzy systems based on a switching fuzzy model and piecewise Lyapunov functions

This paper presents delay-dependent stability analysis and controller synthesis methods for discrete-time Takagi-Sugeno （T-S） fuzzy systems with time delays. The T-S fuzzy system is transformed to an equivalent switching fuzzy system. Consequently, the delay-dependent stabilization criteria are derived for the switching fuzzy system based on the piecewise Lyapunov function. The proposed conditions are given in terms of linear matrix inequalities （LMIs）. The interactions among the fuzzy subsystems are considered in each subregion, and accordingly the proposed conditions are less conservative than the previous results. Since only a set of LMIs is involved, the controller design is quite simple and numerically tractable. Finally, a design example is given to show the validity of the proposed method.