不确定离散时滞系统经动态输出反馈的时滞依赖保性能控制

考虑了不确定离散时滞系统经动态输出反馈的保性能控制器设计问题．利用离散时滞系统的广义系统表示形式以及有关向量交叉乘积项的界的处理方法，以线性矩阵不等式的形式，给出了一个时滞依赖的保性能输出反馈控制器存在的充分条件．一个数值例子说明了所给方法的有效性．     

一类非线性时滞输出反馈系统的自适应控制

针对一类参数化非线性时滞输出反馈系统,提出了一种无记忆自适应跟踪控制器的设计方案.采用时滞滤波器估计系统状态,用Domination处理非线性时滞项,应用Backstepping技术设计控制器和参数自适应律.放宽了对时滞项的要求.通过构建一个Lyapunov＿Krasoviskii泛函,证明了闭环系统的稳定性,实现了对目标轨线的渐近跟踪,保证了所有信号一致有界.实例仿真说明了该方案的可行性.     

Study of delay-independent decentralized guaranteed cost control for large scale systems

This study introduces delay independent decentralized guaranteed cost control design method based on two controller structures for nonlinear uncertain interconnected large scale systems with time delays. First, a set of equivalent Takagi-Sugeno (T-S) fuzzy models are extended to represent the systems. Then a decentralized state-feedback guaranteed cost performance controller is proposed for the fuzzy systems. Based on delay independent Lyapunov functional approach, some sufficient conditions for the existence of the controller can be cast into the feasible problem of LMIs irrespective of the sizes of the time delays so that the system can be asymptotically stabilized for all considered uncertainties whose sizes are not larger than their bounds. Finally, the minimizing approach is proposed to search the suboptimal upper bound value of guaranteed cost function. Moreover, the corresponding conditions are extended into the generalized dynamic output-feedback close-loop system. Finally, the better control performances of the proposed methods are shown by the simulation examples.     

不确定线性时滞系统的一种混杂状态反馈保成本控制及优化设计方法

本文研究一类不确定线性时滞系统的混杂状态反馈保成本控制及优化设计问题.假设存在有限个备选的控制增益已知的控制器,并且其中任何单一的状态反馈控制器都不能镇定系统,基于单Lyapunov函数的方法,给出了混杂状态反馈保成本控制的充分条件及优化设计方案.当备选的控制增益未知时,利用多Lyapunov函数法,同样给出混杂状态反馈保成本控制的充分条件及相应的优化设计方法.最后用仿真验证了文中方法的有效性.     

Delay-dependent guaranteed cost control for T-S fuzzy systems with time delays

This study introduces a guaranteed cost control method for nonlinear systems with time-delays which can be represented by Takagi-Sugeno (T-S) fuzzy models with time-delays. The state feedback and generalized dynamic output feedback approaches are considered. The generalized dynamic output feedback controller is presented by a new fuzzy controller architecture which is of dual indexed rule base. It considers both the dynamic part and the output part of T-S fuzzy model which guarantees that the controller without any delay information can stabilize time-delay T-S fuzzy systems. Based on delay-dependent Lyapunov functional approach, some sufficient conditions for the existence of state feedback controller are provided via parallel distributed compensation (PDC) first. Second, the corresponding conditions are extended into the generalized dynamic output feedback closed-loop system via so-called generalized PDC technique. The upper bound of time-delay can be obtained using convex optimization such that the system can be stabilized for all time-delays whose sizes are not larger than the bound. The minimizing method is also proposed to search the suboptimal upper bound of guaranteed cost function. The effectiveness of the proposed method can be shown by the simulation examples.     

Nonfragile guaranteed cost control for Delta operator-formulated uncertain time-delay systems

With consideration that the controller parameters may vary from the designed value when the controller is realized, based on Lyapunov stability theory, a design method of nonfragile guaranteed cost control for a class of Delta operator-formulated uncertain time-delay systems is studied. A sufficient condition for the existence of the nonfragile guaranteed cost controller is given. A numeric example is then given to illustrate the effectiveness and the feasibility of the designed method. The results show that even if the parameters of the designed controller are of variations, the closed-loop system is still asymptotically stable and the super value of the cost function can also be obtained, while the closed-loop system will be unstable if the variations of the controller parameters are not considered when the controller is designed. The nonfragile guaranteed cost controller derived from the traditional shift operator method may cause the closed-loop system to be unstable, while the nonfragile guaranteed cost controller based on Delta operator method can avoid the unstable problem of the closed-loop system.     

基于T-S模型的非线性时滞系统非脆弱保性能模糊控制

针对一类用T-S模糊模型描述的非线性时滞系统,采用状态反馈的并行分布补偿方法,研究其保守性较小的非脆弱保性能模糊控制问题,使闭环系统在控制器存在加性摄动的情况下,其闭环性能指标值低于确定的上界.利用线性矩阵不等式处理方法,导出了非脆弱保性能模糊控制律的存在条件,通过建立和求解一个线性矩阵不等式问题,给出了非脆弱保性能模糊控制律的设计方法.仿真结果表明了所提出方法的有效性.     

不确定非线性系统的时滞依赖保性能控制

针对一类基于T-S模糊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。对于用T-S模糊模型表示的非线性时滞系统,已知系统的时变时滞本身及其变化率的上界,采用并行分散补偿技术,通过选取合适的Lyapunov函数,推导了依赖时滞上界及变化率上界的时滞保性能模糊控制器存在的充分条件,进而通过建立和求解LMI（线性矩阵不等式）约束的凸优化问题,给出了保性能控制律的设计方法。数值算例表明了该方法的有效性。     

时滞广义区间系统的弹性保性能控制

研究了一类时滞广义区间系统的弹性保性能控制问题.利用线性矩阵不等式处理方法,导出了系统弹性保性能控制器存在的条件,证明了该条件等价于一个线性矩阵不等式的可行性问题,并用该线性矩阵不等式的可行解给出了弹性保性能控制器的一个参数化表示.进一步,通过求解一个凸优化问题,给出了系统的最优弹性保性能控制器的设计方法.最后的数值例子说明了所给方法的有效性.     

一类非线性时滞系统的保性能控制器设计

针对一类具有非线性控制输入的参数不确定时滞系统和给定的保性能指标,研究了此类系统的保性能控制问题.利用Lyapunov稳定性定理和线性矩阵不等式工具,得到了非线性不确定时滞系统的保性能控制存在的充分条件.与现有结果相比,考虑的保性能控制器是非线性的,并且保性能控制器可由线性矩阵不等式的解给出.得到的保性能控制器不仅保证...     

具有随机长时延的网络控制系统保性能控制

本文研究了一类具有随机长时延离散时间网络控制系统(NCSs)的建模和保性能控制问题.用两个马尔可夫链分别来描述反馈通道和前向通道的网络诱导时延,基于采用现有最新数据的原则,将闭环NCS建模成一个与当前时刻和过去时刻网络诱导时延有关的马尔可夫随机时滞系统.应用线性矩阵不等式技术和李亚普诺夫方法得到了闭环NCS随机稳定且具有二次性能指标上界的充分条件,并给出了状态反馈保性能控制器的设计方法.最后,通过数值算例验证了本文方法的有效性.     

基于观测器的广义时滞系统弹性保成本控制

在同时考虑系统矩阵参数不确定性和控制器不确定性对系统性能影响的前提下,研究了一类基于观测器的不确定广义时滞系统的弹性保成本控制问题.基于Lvapunov稳定性理论,通过构造广义Lyapunov函数和广义二次性能指标函数,以线性矩阵不等式的形式给出了基于观测器状态反馈的弹性保成本控制器的设计方法.该控制器不仅保证了广义时滞系统是鲁棒稳定而且使其具有相应的性能指标上界.采用一种新方法将系统弹性保成本控制器设计和状态观测器增益矩阵求取转化为两组严格线性矩阵不等式的可行解问题.最后通过算例验证了该方法的可行性和有效性.     

离散化不确定马尔可夫跳变系统的事件触发保性能控制

针对一类离散化不确定马尔可夫跳变系统,研究了基于事件触发机制的保性能控制问题.首先假设不确定的参数是有界的,与传统的周期触发方式的区别是,事件触发机制可以判断采样信号是否需要传输.其次,利用时间间隔分析法,把事件触发机制和网络时延构造成一个时滞系统,根据时滞分析法,提出了事件触发条件和保性能控制器的协同设计方案.最后,用一个仿真例子验证此算法的有效性.     

不确定时延网络控制系统的保性能控制

在工程实际网络控制系统中,不仅要求系统能够保持稳定,还要系统具有一定的性能指标,采用状态反馈控制是一种非常有效的控制方式。针对一类线性不确定时延网络控制系统,研究了在有记忆状态反馈控制器下的保性能控制问题。利用Lyapunov函数和线性矩阵不等式的方法,给出了网络控制系统保性能控制律存在的条件和相应的状态反馈控制器的设计方法。最后,通过Matlab数值仿真算例验证了该方法的有效性和正确性。     

Adaptive neural network predictive control for nonlinear pure feedback systems with input delay

This paper presents an adaptive neural control design for nonlinear pure-feedback systems with an input time-delay. Novel state variables and the corresponding transform are introduced, such that the state-feedback control of a pure-feedback system can be viewed as the output-feedback control of a canonical system. An adaptive predictor incorporated with a high-order neural network (HONN) observer is proposed to obtain the future system states predictions, which are used in the control design to circumvent the input delay and nonlinearities. The proposed predictor, observer and controller are all online implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed. The conventional backstepping design and analysis for pure-feedback systems are avoided, which renders the developed scheme simpler in its synthesis and application. Practical guidelines on the control implementation and the parameter design are provided. Simulation on a continuous stirred tank reactor (CSTR) and practical experiments on a three-tank liquid level process control system are included to verify the reliability and effectiveness.     

线性不确定时滞系统的可靠保成本控制

讨论了执行器故障下,线性不确定时滞系统的可靠保成本控制问题。提出了更实际、更一般的执行器故障模型;给出了以LMI表达的故障系统渐近隐定以及成本函数有上界的充分条件;进一步对执行器故障情况下的成本函数上界进行了优化,该优化是通过一个LMI组的最小化问题来实现的,对扰动输入具有一定的衰减性能。仿真实例验证了所得结果的有效性。     

不确定时滞系统的保性能控制

基于时滞系统的一个新的指数稳定性定理,考虑了时不变不确定时滞系统的保性能控制问题.利用一种新的分析技术,通过解两个Riccati不等式和一个线性矩阵不等式得一保性能控制器,该控制器可保证闭环系统指数稳定且使系统满足一定的性能指标.与一般的不确定时滞系统保性能控制不同,所得的性能指标的上界中含有参数,可通过调整参数值的大小来使性能指标达到最优.所得Riccati不等式中含有时滞,因此该判据是时滞相关的.数值算例证明了该方法的适用性.     

一类不确定非线性系统的自适应输出反馈镇定

研究了一类不确定非线性系统的全局自适应输出反馈镇定问题. 由于不确定控制系数和未知线性增长率的存在, 这个问题比较复杂且很难解决. 本文引入一个新的在线调节的动态增益, 并基于此设计了高增益K-滤波器用于重构系统的状态. 然后, 受广义控制方法的启发, 发展了反推法并设计了自适应输出反馈镇定控制器. 结果表明, 通过选择恰当的设计参数可以保证闭环系统的全局稳定性. 给出的仿真算例验证了本文理论结果的正确性.     

一类时滞组合系统的优化保成本容错控制

对一类时滞组合系统，研究了依赖时滞的分散状态反馈可靠保成本控制器的设计问题．采用线性矩阵不等式方法，导出了时滞依赖可靠保成本控制器的存在条件和参数化表示．进而，通过建立和求解一个线性矩阵不等式组约束的凸优化问题，给出了优化保成本容错控制器的设计方法．仿真实例验证了这个设计法的有效性．     

A stabilizing output-feedback linear quadratic control for pure input-delayed systems

This paper proposes the design of a stabilizing output-feedback linear quadratic controller for a pure input-delayed system. By reducing a pure input-delayed system into a non-delayed system and modifying the linear quadratic cost, a simple, stabilizing output-feedback linear quadratic controller is formulated in terms of linear matrix inequalities. The worst-case output-feedback LQ controller is also presented with respect to the unknown initial states. A numerical example is given to illustrate the performance of the proposed controllers.