Delay-dependent robust H∞ control for a class of uncertain switched systems with time delay

For linear switched system with both parameter uncertainties and time delay, a delay-dependent sufficient condition for the existence of a new robust H infinity feedback controller was formulated in nonlinear matrix inequalities solvable by an LMI-based iterative algorithm. Compared with the conventional state-feedback controller, the proposed controller can achieve better robust control performance since the delayed state is utilized as additional feedback information and the parameters of the proposed controllers are changed synchronously with the dynamical characteristic of the system. This design method was also extended to the case where only delayed state is available for the controller. The example of balancing an inverted pendulum on a cart demonstrates the effectiveness and applicability of the proposed design methods.     

H∞ control for uncertain Markovian jump systems with mode-dependent mixed delays

We study the problem of H_∞ control for a class of Markovian jump systems with norm-bounded parameter uncertainties and modedependent mixed delays including discrete delays and distributed delays in this paper. Our aim is to present a new delay-dependent control approach such that the resulting closed-loop system is robust mean-square (MS) exponentially stable and satis?es a prescribed H_∞ performance level, irrespective of the parameter uncertainties. Such delay-dependent approach does not require system transformation or free-weighting matrix. A numerical example shows that the results are less conservative and more e?ective.     

H∞ control for uncertain Markovian jump systems with mode-dependent mixed delays

We study the problem of H∞ control for a class of Markovian jump systems with norm-bounded parameter uncertainties and mode-dependent mixed delays including discrete delays and distributed delays in this paper. Our aim is to present a new delay-dependent control approach such that the resulting closed-loop system is robust mean-square （MS） exponentially stable and satisfies a prescribed H∞ performance level, irrespective of the parameter uncertainties. Such delay-dependent approach does not require system transformation or free-weighting matrix. A numerical example shows that the results are less conservative and more effective.     

H∞control for uncertain Markovian jump systems with mode-dependent mixed delays

We study the problem of H∞ control for a class of Markovian jump systems with norm-bounded parameter uncertainties and mode-dependent mixed delays including discrete delays and distributed delays in this paper. Our aim is to present a new delay-dependent control approach such that the resulting closed-loop system is robust mean-square (MS) exponentially stable and satisfies a prescribed H∞ performance level, irrespective of the parameter uncertainties. Such delay-dependent approach does not require system transformation or free-weighting matrix. A numerical example shows that the results are less conservative and more effective.     

Robust L2–L∞ control for uncertain singular systems with time-varying delay

We study the problem of L₂–L_∞ control for a class of uncertain singular systems with time-delay and norm-bounded parameter uncertainties in this paper. A new delay-dependent robust stability criterion is obtained in terms of linear matrix inequalities (LMIs). Based on this criterion, a state feedback controller is designed to guarantee that the closed-loop system is regular, impulse free and stable with a prescribed L₂–L_∞ performance satis?ed for all admissible parameter uncertainties. A simulation example is included to illustrate the e?ectiveness of the proposed method.     

Delay-dependent robust H∞ control for uncertain fuzzy hyperbolic systems with multiple delays

The robust H∞ control problem was considered for a class of fuzzy hyperbolic model (FHM) systems with parametric uncertainties and multiple delays. First, FHM modeling method was presented for time-delay nonlinear systems. Then, by using Lyapunov-Krasovskii approaches, delay-dependent sufficient condition for the existence of a kind of state feedback controller was proposed, which was expressed as linear matrix inequalities (LMIs). The controller can guarantee that the resulting closed-loop system is robustly asymptotically stable with a prescribed H∞ performance level for all admissible uncertainties and time-delay. Finally, a simulation example was provided to illustrate the effectiveness of the proposed approach.     

带有多个离散和分布时滞的不确定系统的鲁棒自适应控制

对于带有多个离散和分布时滞且有外部干扰的不确定线性系统提出一类鲁棒自适应控制方案.系统的不确定性是范数有界的未知连续函数,外部干扰是扇形有界的.分2步证明其结论:首先用线性矩阵不等式方法说明状态反馈控制可以保证系统的确定部分的稳定性;其次由于系统的不确定部分的上界未知,用自适应的方法来估计上界的值;利用径向基函数神经网络来估计关于状态的未知连续函数;最终证明了在结合状态反馈和自适应神经网络控制的复合控制律作用下闭环系统是渐近稳定的.然后,在第一步基础上,要求系统满足2个不等式条件,设计相应的控制律参数,用Lyapunov-Krasovskii泛函方法证明了闭环系统是指数稳定的.     

线性时滞不确定系统的时滞相关鲁棒镇定

讨论了同时具有输入时滞与状态时滞的不确定线性系统的时滞相关鲁棒镇定问题.运用矩阵分解思想和Lyapunov-Karsovskii泛函方法,在处理V的导数时添加一个恰当的0项,引入自由权矩阵,基于LMI方法获得了系统经无记忆状态反馈后可鲁棒镇定的时滞相关充分条件,同时获得了具体的控制器设计方法.数值例子说明所得结论具有较小的保守性.     

带状和输入时滞的不确定系统的鲁棒保成本控制

针对一类带有状态滞和输入滞的不确定时滞系统,研究了鲁棒保成本控制器设计问题。在适当的假设下利用Lyapunov稳定性方法,给出了系统时滞相关的鲁棒稳定性判别方法,并采用一个新的积分不等式方法,用线性矩阵不等式最优化途径解决了这类保成本控制问题。通过求解相应的性矩阵不等式就得到了系统的鲁棒保成本控制器,同时也能保证二次性能函数不超过一个确定的界。最后给出数值例子验证了所给方法的有效性。     

不确定时滞系统的鲁棒稳定性研究

基于Layunov稳定性理论,研究了不确定性不满足匹配条件的时滞系统鲁棒稳定性问题.采用线性矩阵不等式方法,提出了不确定时滞系统鲁棒稳定控制器存在的充分条件,并给出使得闭环系统鲁棒稳定的状态反馈控制律设计方法.最后数值实例的仿真结果验证了文中设计方法的正确性。     

不确定非线性时滞系统的时滞依赖保性能控制

文章针对一类基于T-S模型表示的具有时变状态时滞和范数有界不确定性非线性系统,研究了时滞依赖保性能模糊控制器设计问题,推导了此类不确定系统的时滞依赖保性能模糊控制器存在的充分条件,此充分条件等价于3类线性矩阵不等式的可解性;通过建立和求解线性矩阵不等式约束的凸优化问题,给出了最优保性能控制律的设计方法。     

混合变时延中立型控制系统的鲁棒稳定性新准则

研究了具有混合区间变时延和分式不确定性的中立型控制系统的鲁棒稳定性.首先,在系统参数不确定性不存在时,通过构造改进型的Lyapunov-Krasovskii泛函,利用Jesnen积分不等式并引入少量自由权矩阵,综合矩阵凸组合与交互式凸组合等方法,有效估计了Lyapunov-Krasovskii泛函导函数上界,并基于线性矩阵不等式建立了时延相关的渐近稳定性判据.考虑系统参数具有不确定性时,通过引入改进的有界实引理,给出了系统的鲁棒稳定性准则,且易于借助Matlab工具箱中的LMI进行验证.数值算例和比较结果说明该准则的保守性较弱.     

具有状态和控制滞后离散系统的容错保成本控制

基于T-S模糊模型,通过无记忆状态反馈研究了一类带有状态和控制滞后的不确定离散时滞系统容错保成本控制问题。应用线性矩阵不等式(LM I)给出系统存在执行器故障时,模糊闭环系统渐近稳定的充分条件,该条件保证了对所有允许的不确定性闭环系统渐近稳定,而且对于给定的二次型成本函数,能保证闭环成本不超过某个界。算例表明该方法是有效的。     

多时滞非线性不确定中立型系统的时滞相关性鲁棒镇定

对一类具有多时滞非线性不确定项的中立型系统的鲁棒反馈控制问题，构造了Lyapunov泛函，给出了通过带记忆的反馈控制律，使闭环系统一致渐近稳定的分别与滞后量大小无关和相关的充分条件．