T-S模糊系统的鲁棒耗散控制

通过应用Lyapunov稳定性理论,研究了具有参数不确定性的T-S模糊系统的鲁棒稳定性和耗散性。具有参数不确定性的T-S模糊模型可以以任意精度近似连续非线性不确定系统。假设系统中的参数不确定性是范数有界的。利用Lyapunov稳定性理论给出了鲁棒耗散控制器存在的充分条件。通过解一组线性矩阵不等式(LMIs),可获得鲁棒耗散控制器。设计的鲁棒耗散控制器能够保证对于T-S模糊系统中所有的参数不确定性,闭环系统都是稳定的,且满足给定的耗散性能指标。数值例子证明了方法的有效性。     

参数不确定的非线性随机时滞系统的H∞滤波

研究了一类带有参数不确定性的非线性随机时滞系统的鲁棒H∞滤波问题.假设参数不确定性是范数有界的并且系统的动态方程是由伊藤微分方程所描述的.对所有容许的参数不确定性以及外界干扰,构造一个线性、无时滞、不确定性及独立的状态滤波器,使滤波误差动态系统是指数均值稳定并且独立于时滞的.针对单时滞系统和多时滞系统两种情况,基于线性矩阵不等式(LMI)方法给出了保证鲁棒H∞滤波存在的充分性条件.最后,数值仿真结果很好地说明了该方法的有效性.     

基于LMI的非线性系统PDC控制器设计方法

针对T-S模糊模型描述的非线性系统，提出了一种PDC控制器的直接设计方法。将闭环控制系统的稳定要求、性能指标及控制量约束条件统一到线性矩阵不等式的框架内，通过求解线性矩阵不等式族获得控制器参数。以倒立摆系统为例，对提出的设计方法进行了验证，仿真结果表明设计方法是有效的。     

连续时滞模糊系统的H∞滤波

研究了一类非线性连续时滞系统的H∞滤波器的设计问题。基于T-S模糊模型来设计模糊H∞滤波器,该滤波器能确保滤波误差系统的渐近稳定并能满足给定的H∞性能指标。在设计过程中考虑了系统的时滞,从而降低了滤波器设计的保守性,根据线性矩阵不等式(LMI)给出线性滤波器存在的充分条件。通过仿真算例验证了设计方法的有效性。     

非线性时滞系统的一种模糊H∞控制方案

研究了非线性时滞系统基于T-S模型的模糊H∞控制问题.针对一类控制对象,得到了存在模糊H∞控制器的充分条件.此充分条件等价于一类线性矩阵不等式(LMI)的可解性.     

非线性系统的T-S模糊建模与控制

研究了非线性系统的T-S模糊建模与控制问题，并应用到一级倒立摆的模糊建模中，采用并行分配补偿法（PDC）设计控制器，并用线性矩阵不等式（LMI）计算控制器参数，仿真验证建模正确，控制器简洁有效。     

非线性时滞系统的一种模糊$H_{\infty}$控制方案

研究了非线性时滞系统基于T-S模型的模糊$H_{\infty}$控制问题.针对一类控制对象,得到了存在模糊$H_{\infty}$控制器的充分条件.此充分条件等价于一类线性矩阵不等式(LMI)的可解性.     

离散非线性随机时滞系统的l2-l∞模糊滤波

应用Takagi-Sugeno(T-S)模糊模型,研究了一类离散非线性随机时滞系统的鲁棒模糊滤波问题.在随机稳定性意义下,提出了基于LMI的鲁棒模糊滤波器的系统化设计方法,使相对于所有能量有界的外界干扰信号,滤波误差动态系统的l2-l∞噪声抑制水平小于指定的值.仿真结果表明了所提方法的有效性和可行性.     

基于T-S模型的非线性系统离散时间滑模控制

基于T-S模糊模型,讨论了一类非线性离散时间系统的控制问题。采用T-S模糊模型来描述非线性系统的动态模型,再将非线性系统的全局T-S模糊模型转化为线性不确定系统的模型。这样复杂的非线性系统的稳定问题就转化为线性不确定系统的鲁棒镇定问题。采用离散时间滑模控制方法实现线性不确定系统的鲁棒镇定。利用用线性矩阵不等式技术设计稳定的滑动模面,以降低非匹配不确定对系统的影响。给出了线性矩阵不等式形式的稳定滑动模面存在的充分条件。此外还给出了滑模控制律的设计方法。所给设计方法可保证系统鲁棒镇定,并且在滑动模面附近的抖振可明显减弱。最后,给出了truck-trailer的仿真算例,证明了所给方法的可行性和有效性。     

混沌系统基于T-S模糊模型的控制方法

将模糊控制技术应用于混沌控制中，可以克服反馈线性化等传统方法对参数完全精确已知的限制；用T-S模糊系统来逼近非线性系统，它的IF-THEN规则后件由线性状态空间子系统构成，进而可以应用模糊系统的控制理论求得模糊控制器，用此非线性控制器来控制非线性系统，以求良好的控制效果；模糊规则后件部分以局部线性方程形式给出的T-S模糊模型可以通过调整相关参数很好地逼近混沌系统，基于该模型采用平行分散补偿技术设计出具有相同规则数目的模糊控制器，控制器所有参数可以通过求解一组线性矩阵不等式一次性得到。仿真结果验证了该方法的有效性。     

一类基于神经网络非线性随机系统自适应滤波

给出非线性MIMO随机系统可观性定义和条件，将非线性SISO确定性系统局部可观性理论拓展到非线性MIMO随机系统，基于这一理论在系统模型和噪声统计未知情况下，提出一类基于神经网络的非线性离散随机系统自适应滤波器的设计方法，考虑过程方程的动态特性和输出方程的静态特性，设计了动态神经网络作为系统的滤波器，前馈神经网络作为系统的输出预报器，充分利用已知观测信息训练两个神经网络，从而提高了状态估计的精度，该方法克服了扩展Kalman滤波要求模型和统计特性精确已知的不足，仿真例子验证了所提出的估计方法的有效性。     

Robust reliable guaranteed cost control for nonlinear singular stochastic systems with time delay

To study the design problem of robust reliable guaranteed cost controller for nonlinear singular stochastic systems,the Takagi-Sugeno(T-S)fuzzy model is used to represent a nonlinear singular stochastic system with norm-bounded parameter uncertainties and time delay.Based on the linear matrix inequality(LMI)techniques and stability theory of stochastic differential equations,a stochastic Lyapunov function method is adopted to design a state feedback fuzzy controller.The resulting closed-loop fuzzy system is robustly reliable stochastically stable,and the corresponding quadratic cost function is guarauteed to be no more than a certain upper bound for all admissible uncertainties,as well as different actuator fault cases.A sufficient condition of existence and design method of robust reliable guaranteed cost controller is presented.Finally,a numerical simulation is given to illustrate the effectiveness of the proposed method.     

Robust dissipative control for time-delay stochastic jump systems

A robust dissipative control problem for a class of It?-type stochastic systems is discussed with Markovian jumping parameters and time-varying delay. A memoryless state feedback dissipative controller is developed based on Lyapunov-Krasovskii functional approach such that the closed-loop system is robustly stochastically stable and weakly delay-dependent (RSSWDD) and strictly (Q, S, R)-dissipative. The sufficient condition on the existence of state feedback dissipative controller is presented by linear matrix inequality (LMI). And the desired controller can be concluded as solving a set of LMI. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed approach.     

Robust dissipative filtering for continuous-time polytopic uncertain neutral systems

This article is concerned with the problem of robust dissipative filtering for continuous-time polytopic uncertain neutral systems. The main purpose is to obtain a stable and proper linear filter such that the filtering error system is strictly dissipative. A new criterion for the dissipativity of neutral systems is first provided in terms of linear matrix inequalities (LMI). Then, an LMI sufficient condition for the existence of a robust filter is established and a design procedure is proposed for this type of systems. Two numerical examples are given. One illustrates the less conservativeness of the proposed criterion; the other demonstrates the validity of the filtering design procedure.     

随机可变时滞系统的渐近稳定性

讨论了一类随机可变时滞系统解的渐近稳定性。应用It 公式、半鞅收敛定理与多个Lyapunov函数建立了这类随机可变时滞系统渐近稳定性的有效判据,使实际应用中构造Lyapunov函数更为方便。同时也说明了结果包含经典的随机系统稳定性结果为其特殊情况。与经典的随机稳定性理论相比,所建立的稳定性结果无须LV负定,充分利用了随机扰动项的作用,并且从理论上解释了一个不稳定的系统有时加入适当随机扰动后反而稳定。最后,举例说明了结果的有效性     

不确定非线性跳变系统滑模耗散控制

针对既含有连续时间演化,又含有马尔可夫事件驱动的一类非线性不确定混杂动态跳变系统,研究相异滑模面上的耗散控制问题。对于跳变系统所具有的匹配的不确定性,可根据滑模控制理论,设计比例-积分多滑模面及相应滑模控制器。与此同时利用耗散控制理论并结合线性矩阵不等式,得到存在非线性和非匹配不确定性滑模面的无记忆状态耗散控制器。如此,系统滑模耗散控制器便可给出。最后数值事例验证定理的正确性。     

高阶随机非线性系统状态反馈镇定

针对一类高阶下三角随机非线性系统,提出一种新的镇定方案,采用增加一个幂积分的工具构建了一个全局稳定的光滑状态反馈控制律。通过反馈占有设计方法和Young不等式处理随机系统的非线性项,取消了对随机非线性系统反馈线性化和控制输入呈线性的要求,基于Lyapunov方法,证明了闭环系统依概率全局渐近稳定。最后,仿真实例说明了算法的可行性。     

Bayesian estimation for nonlinear stochastic hybrid systems with state dependent transitions

The Bayesian approach is considered as the most general formulation of the state estimation for dynamic systems.However,most of the existing Bayesian estimators of stochastic hybrid systems only focus on the Markov jump system,few literature is related to the estimation problem of nonlinear stochastic hybrid systems with state dependent transitions.According to this problem,a new methodology which relaxes quite a restrictive assumption that the mode transition process must satisfy Markov properties is proposed.In this method,a general approach is presented to model the state dependent transitions,the state and output spaces are discreted into cell space which handles the nonlinearities and computationally intensive problem offline.Then maximum a posterior estimation is obtained by using the Bayesian theory.The efficacy of the estimator is illustrated by a simulated example.     

Delay-dependent exponential stability of impulsive stochastic systems with time-varying delay

The problem of delay-dependent exponential stability is investigated for impulsive stochastic systems with time-varying delay.Although the exponential stability of impulsive stochastic delay systems has been discussed by several authors,few works have been done on delay-dependent exponential stability of impulsive stochastic delay systems.Firstly,the Lyapunov-Krasovskii functional method combing the free-weighting matrix approach is applied to investigate this problem.Some delay-dependent mean square exponential stability criteria are derived in terms of linear matrix inequalities.In particular,the estimate of the exponential convergence rate is also provided,which depends on system parameters and impulsive effects.The obtained results show that the system will stable if the impulses’ frequency and amplitude are suitably related to the increase or decrease of the continuous flows,and impulses may be used as controllers to stabilize the underlying stochastic system.Numerical examples are given to show the effectiveness of the results.     

Mean-square exponential stability for stochastic time-varying delay systems with Markovian jumping parameters: a delay decomposition approach

The mean-square exponential stability problem is investigated for a class of stochastic time-varying delay systems with Markovian jumping parameters.By decomposing the delay interval into multiple equidistant subintervals,a new delay-dependent and decay-rate-dependent criterion is presented based on constructing a novel Lyapunov functional and employing stochastic analysis technique.Besides,the decay rate has no conventional constraint and can be selected according to different practical conditions.Finally,two numerical examples are provided to show that the obtained result has less conservatism than some existing ones in the literature.