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.     

T-S 模糊时滞模型的时滞相关稳定性分析和镇定

研究一类用T—S模糊模型描述的非线性不确定时滞系统的时滞相关鲁棒镇定问题．基于线性矩阵不等式的可行解，首先给出利用T—S模糊模型描述的非线性时滞系统时滞相关稳定性准则；然后给出了经状态反馈鲁棒镇定设计的新方法．所设计的控制器能确保闭环系统渐近稳定．     

非线性扰动不确定时滞系统时滞相关鲁棒观测器设计

研究一类具有非线性扰动的不确定时滞系统的时滞相关鲁棒稳定性及其基于观测器 的时滞相关鲁棒控制问题.将线性矩阵不等式(LMI,1inear matrix inequality)与数值不等式 (AVI,algebraic value inequality)方法相结合给出了开环系统渐近稳定及其指数稳定的时滞相 关条件.并设计了系统的观测器,给出了该系统基于观测器的时滞相关可镇定条件.     

一类多通道不确定时滞大系统分散鲁棒H∞控制：LMI方法

研究多通道不确定时滞大系统的鲁棒分散H_∞控制问题. 假定不确定性是时不变、范数有界, 且存在于系统、时滞和输出矩阵中. 主要针对动态输出反馈控制问题. 基于Lyapunov稳定性理论, 通过设定Lyapunov矩阵为合适的块对角结构, 采用矩阵替换的方法推导出了使多通道不确定时滞大系统可鲁棒镇定, 且满足一定的扰动水平的时滞依赖充分条件即线性矩阵不等式(LMI) 有可行解, 并且给出了具有期望阶数的分散鲁棒控制器的设计方法. 数值例子说明了本文提出方法的有效性.     

基于观测器的时滞系统鲁棒控制器的设计

研究了一类不确定时滞系统基于观测器的鲁棒镇定问题,系统的不确定性时变未知且范数有界,目的是设计状态观测器和线性无记忆观测状态反馈控制器,使其能够镇定一类状态和控制输入不确定性时滞系统。基于Lyapunov稳定性理论,采用线形矩阵不等式这一有效工具,给出了系统基于观测状态反馈鲁棒镇定的充分条件,并且利用线形矩阵不等式的解构造了使得系统鲁棒稳定的基于观测状态反馈控制器,所得结果与时滞相关,从而相对减弱了控制器设计的保守性。数值算例表明了所提出的设计方法的有效性。     

一类含未建模动态的奇异时滞系统的鲁棒镇定问题

利用线性矩阵不等式的方法,研究了一类同时含有参数摄动和未建模动态的线性奇异时滞系统的鲁棒镇定问题.得到了系统可鲁棒镇定的一个充分条件,用线性矩阵不等式的方法,将控制器的求解问题转化为受限线性矩阵不等式的求解问题,并给出了受限线性矩阵不等式的具体解法．最后举例说明了所提出方法的正确性．     

不确定时滞广义双线性系统的鲁棒镇定

针对不确定参数是时变但满足匹配条件的时滞广义双线性系统的鲁棒控制问题进行了研究,设计状态反馈鲁棒控制器,使得所有满足条件的不确定时滞广义双线性系统鲁棒稳定.基于Lyapunov稳定性理论,采用线性矩阵不等式方法,提出了不确定时滞广义双线性系统鲁棒镇定的充分条件,并给出了使得闭环系统鲁棒镇定的状态反馈控制器设计方法.定理解决了介于非线性和线性之间的不确定时滞广义双线性系统的有关理论.仿真实例说明了定理的有效性和合理性.     

时滞线性区间系统的鲁棒稳定与鲁棒镇定

利用一个微分不等式给出了几类具有区间 系数的时滞系统的鲁棒稳定和鲁棒镇定的充分条件,这些条件只需判断一个常数矩阵是否为 M矩阵,使用方便．     

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.     

线性不确定时滞系统指定衰减度鲁棒镇定

研究了一类线性不确定时滞系统时滞依赖型具有指定衰减度的无记忆状态反馈鲁 棒镇定问题.所考虑的线性不确定时滞系统含有时变未知但有界的不确定参数和状态滞后. 通过应用Razumikhin定理和Lyapunov定理,导出了系统鲁棒稳定且具有指定衰减度的判 据和具有指定衰减度的无记忆状态反馈鲁棒镇定控制律存在的充分条件及相应的控制器设 计方法.所得时滞相关的结果用一组线性矩阵不等式(LMI)表示.     

Delay-dependent robust stabilization of uncertain state-delayed systems

This paper concerns a problem of robust stabilization of uncertain state-delayed systems. A new delay-dependent stabilization condition using a memoryless controller is formulated in terms of matrix inequalities. An algorithm involving convex optimization is proposed to design a controller guaranteeing a suboptimal maximal delay such that the system can be stabilized for all admissible uncertainties.     

New Robust Stability Conditions and Design of Robust Stabilizing Controllers for Takagi–Sugeno Fuzzy Time-Delay Systems

In this paper, we consider robust stability and stabilization of uncertain Takagi-Sugeno fuzzy time-delay systems where uncertainties come into the state and input matrices. Some stability conditions and robust stability conditions for fuzzy time-delay systems have already been obtained in the literature. However, those conditions are rather conservative and do not guarantee the stability of a wide class of fuzzy systems. This is true in case of designing stabilizing controllers for fuzzy time-delay systems and it thus leads to a conservative fuzzy controller design as well. We first consider rather relaxed robust stability conditions of uncertain fuzzy systems. To this end, we introduce an auxiliary system to the original fuzzy time-delay system to obtain generalized delay-dependent stability conditions. Such an auxiliary system has some arbitrary matrices that generalize not only the system representation but also delay-dependent stability conditions. Conditions we obtain here are delay-dependent conditions that depend on the upper bound of time-delay, and are given in terms of linear matrix inequalities (LMIs). Then, we compare our delay-dependent stability conditions with other conditions in the literature, and show that our conditions guarantee the stability of a wider class of systems than others. Next, we consider the robust stabilization problem with memoryless and delayed state feedback controllers. Based on our generalized robust stability conditions, we obtain delay-dependent sufficient conditions for the closed-loop system to be robustly stable, and give a design method of robustly stabilizing controllers. Finally, we give three examples that illustrate our results.     

具有多输入时滞的不确定广义系统的时滞相关鲁棒镇定

研究具有多输入时滞及参数不确定性的广义系统的时滞相关鲁棒镇定问题. 首先利用LMI给出相应的标称系统的时滞相关镇定准则. 然后, 基于这个准则, 设计状态反馈控制器, 使得对任何允许的不确定参数相应的闭环系统是正则, 稳定, 无脉冲的. 最后的数值算例表明所提方法是有效的.     

Delay-dependent robust stabilization for uncertain singular systems with discrete and distributed delays

This paper investigates the problem of delay-dependent robust stabilization for uncertain singular systems with discrete and distributed delays in terms of linear matrix inequality （LMI） approach. Based on a delay-dependent stability condition for the nominal system, a state feedback controller is designed, which guarantees the resultant closed- loop system to be robustly stable. An explicit expression for the desired controller is also given by solving a set of matrix inequalities. Some numerical examples are provided to illustrate the less conservativeness of the proposed methods.     

Passivity-based decentralized stabilization of multi-agent systems with uncertainty and mixed delays

In this paper, we investigate a decentralized stabilization problem of uncertain multi-agent systems with mixed delays including discrete and distributed time-varying delays based on passivity stability. We design a decentralized state-feedback stabilization scheme such that the family of closed-loop feedback subsystems enjoys the delay-dependent passivity stability for each subsystem. Then, by employing a new Lyapunov-Krasovskii function, a linear matrix inequality （LMI） approach is developed to establish the delay-dependent criteria for the passivity stability of multi-agent systems. The sufficient condition is given for checking the passivity stability. The proposed LMI result is computationally efficient. An example is given to show the effectiveness of the method.     

Decentralized robust controller design for uncertain large-scale systems with control delays

This paper presents a decentralized robust controller design for a class of interconnected dynamic systems with control delays and parametric uncertainty. The parameter uncertainties are considered unknown but norm bounded. By applying the Lyapunov stability theorem, two new delay-dependent sufficient conditions are established in terms of linear matrix inequalities, and linear memoryless state feedback controllers are designed to maintain the robust stability for the class of systems under study. It is shown that either no tuning procedure is required or only one parameter from each inequality needs to be tuned. An example is presented to demonstrate the application of the results presented here.     

Delay-dependent robust stabilization for uncertain singular systems with discrete and distributed delays

This paper investigates the problem of delay-dependent robust stabilization for uncertain singular systems with discrete and distributed delays in terms of linear matrix inequality (LMI) approach. Based on a delay-dependent stability condition for the nominal system, a state feedback controller is designed, which guarantees the resultant closedloop system to be robustly stable. An explicit expression for the desired controller is also given by solving a set of matrix inequalities. Some numerical examples are provided to illustrate the less conservativeness of the proposed methods.     

Robust fuzzy controller for large-scale nonlinear systems using decentralized static output-feedback

This paper addresses a robust fuzzy control problem for an uncertain large-scale nonlinear system using decentralized static output-feedback scheme for both continuous-time and discrete-time cases. In both cases, sufficient design conditions are derived for robust asymptotic stabilization in terms of linear matrix inequalities (LMIs), and are therefore easily tractable by convex optimization. An illustrative example, a two-area power system with parametric uncertainties and the valve-position limit nonlinearity is provided to verify the effectiveness of the proposed technique.     

New Approach to Delay-Dependent Stability Analysis and Stabilization for Continuous-Time Fuzzy Systems With Time-Varying Delay

This paper is concerned with delay-dependent stability analysis and stabilization problems for continuous-time Takagi and Sugeno (T-S) fuzzy systems with a time-varying delay. A new method for the delay-dependent stability analysis and stabilization is suggested, which is less conservative than other existing ones. First, based on a fuzzy Lyapunov-Krasovskii functional (LKF), a delay-dependent stability criterion is derived for the open-loop fuzzy systems. In the derivation process, some free fuzzy weighting matrices are introduced to express the relationships among the terms of the system equation, and among the terms in the Leibniz-Newton formula. Then, a delay-dependent stabilization condition based on the so-called parallel distributed compensation (PDC) scheme is worked out for the closed-loop fuzzy systems. The proposed stability criterion and stabilization condition are represented in terms of linear matrix inequalities (LMIs) and compared with the existing ones via two examples. Finally, application to control of a truck-trailer is also given to illustrate the effectiveness of the proposed design method.