基于模糊模型的非线性不确定时滞系统的H-infinite鲁棒容错控制

研究了一类具有不确定时滞的非线性系统的H_∞鲁棒容错控制问题. 采用T-S模糊模型来描述非线性系统,并对执行器失效且具有扰动的情形, 基于Lyapunov稳定性理论和LMI方法, 给出了系统H_∞鲁棒容错控制器存在的充分条件, 保证了系统的鲁棒稳定性. 仿真实例验证了本文提出方法的有效性.     

基于模糊T-S模型的非线性系统的H∞鲁棒容错控制

研究一类具有不确定和时滞的非线性系统的H鲁棒容错控制问题.采用T-S模糊模型来描述非线性系统,在系统执行器失效的情况下,建立故障矩阵模型;通过引进自由加权矩阵,基于Lyapunov稳定性理论和LMI(线性矩阵不等式)方法,给出系统H鲁棒容错控制器存在的充分条件,保证了系统的鲁棒稳定性,仿真实例验证了该方法的有效性.     

基于T-S模型的双时变时滞不确定系统的鲁棒H∞容错控制

为了解决系统在含有执行器局部或者完全失效故障情况下的鲁棒H∞容错控制问题, 针对一类状态和控制输入同时存在时变时滞的不确定非线性系统, 采用T-S模糊模型来描述, 利用并行分布补偿（PDC）算法设计了模糊状态反馈控制器, 结合Lyapunov稳定性理论给出了保证该模糊容错控制系统渐近稳定的充分条件, 不但保证了系统输出的鲁棒稳定性, 而且能够满足给定的鲁棒H∞性能指标。最后通过MATLAB仿真对比系统中有外部干扰和无外部干扰情况下的系统输出曲线, 验证了所提出方法的可行性。     

参数不确定性时滞系统的鲁棒H∞容错控制器设计

研究了一类同时具有参数不确定性、外界干扰和时滞的线性系统执行器失效的问题,给出了该系统一种鲁棒Ｈ∞容错控制器的失效执行器的输出信号是任意能量有界的干扰信号,不确定线性时滞系统的容错控制问题转化成了鲁棒Ｈ∞控制问题,控制器可以通过解修正的代数黎卡提方程得到,而且控制器与时滞常数无关,设计例子证明了所给方法的有效性。     

一类不确定非线性系统的鲁棒H∞控制

讨论了在自由系统和输入通道都带有有界不确定性的仿射非线性系统的鲁棒H∞控制问题,给出了状态反馈控制设计,对所有允许的不确定性它既能保证关于H∞模的干扰抑制品质,又能镇定该系统.同时指出如果一个相应的Hamilton-Jacobi不等式有非负解,则该不确定仿射非线性系统的鲁棒H∞控制问题可解.     

时滞不确定广义系统的鲁棒H∞容错控制

研究了具有状态时滞和参数不确定性的广义系统的鲁棒H∞容错控制问题,就执行器故障情形,基于广义Ricatti不等式,给出了故障发生时闭环系统仍保持渐近稳定的充分条件和控制器的设计方法,且状态反馈控制器可通过求解LMI得到.数值例子验证了设计方法的有效性.     

不确定广义模糊系统的鲁棒模糊H∞控制器设计

研究了不确定广义模糊系统鲁棒H∞状态反馈控制器和动态输出反馈控制器设计问题。在E确定其它系数矩阵均存在不确定性情况下，给出鲁棒模糊H∞状态反馈控制器和动态输出反馈控制器存在的充分条件。鲁棒H∞状态反馈控制律的设计可能通过求解线性矩阵不等式得到，而动态输出反馈鲁棒H∞控制器可通过定义新变量得到，所求控制器使闭环系统对所有的不确定性稳定且满足H∞性能指标γ。     

基于模糊T-S模型的非线性系统的H∞鲁棒容错控制

研究一类具有不确定和时滞的非线性系统的H_∞鲁棒容错控制问题.采用T-S模糊模型来描述非线性系统,在系统执行器失效的情况下,建立故障矩阵模型;通过引进自由加权矩阵,基于Lyapunov稳定性理论和LMI(线性矩阵不等式)方法,给出系统H_∞鲁棒容错控制器存在的充分条件,保证了系统的鲁棒稳定性.仿真实例验证了该方法的有效性.     

一类非线性不确定时滞系统的鲁棒镇定

基于Ｌｙａｐｕｎｏｖ稳定性理论,了一类具有状态非线性不确定线性时滞系统的鲁棒稳定的一个充分条件。通过求解一个代数Ｒｉｃｃａｔｉ方程即可获得鲁棒稳定控制器,并且该控制器不依赖于系统的时滞。具体算例说明了该方法有效性。     

一类非线性不确定系统的鲁棒H∞控制

利用Hamilton-Jacobi不等式讨论了一类含不确定项的非线性控制系统的鲁棒H∞控制问题,分别得到了状态反馈控制器和动态输出反馈控制器,使得相应的闭环系统具有鲁棒H∞特性的充分条件,并且给出了它们的具体设计.     

多输入多输出多重时延非线性系统的自适应模糊控制

针对多输入多输出多重时延非线性系统,提出了一种自适应模糊跟踪控制方案．该方案有机综合了自适应控制和H∞控制.文中构建了一种自适应时延模糊逻辑系统用来逼近有多重时延的未知函数;设计了H∞补偿器来抵消模糊逼近误差和外部扰动．根据跟踪误差给出了参数调节规律．构造了包含时延的李雅普诺夫函数,从而证明了误差闭环系统满足期望的H∞跟踪性能．仿真结果表明了该方案的可行性．     

多输入多输出多重时延非线性系统的白适应模糊控制

针对多输入多输出多重时延非线性系统,提出了一种自适应模糊跟踪控制方案.该方案有机综合了自适应控制和H∞控制.文中构建了一种自适应时延模糊逻辑系统用来逼近有多重时延的未知函数;设计了H∞补偿器来抵消模糊逼近误差和外部扰动.根据跟踪误差给出了参数调节规律.构造了包含时延的李雅普诺夫函数,从而证明了误差闭环系统满足期望的H∞跟踪性能.仿真结果表明了该方案的可行性.     

Robust adaptive control of nonlinear systems with unknown time delays

In this paper, robust adaptive control is presented for a class of parametric-strict-feedback nonlinear systems with unknown time delays. Using appropriate Lyapunov-Krasovskii functionals, the uncertainties of unknown time delays are compensated for. Controller singularity problems are solved by employing practical robust control and regrouping unknown parameters. By using differentiable approximation, backstepping design can be carried out for a class of nonlinear systems in strict-feedback form. It is proved that the proposed systematic backstepping design method is able to guarantee global uniform ultimate boundedness of all the signals in the closed-loop system and the tracking error is proven to converge to a small neighborhood of the origin. Simulation results are provided to show the effectiveness of the proposed approach.     

基于模糊模型的不确定非线性系统鲁棒D 镇定

针对 T- S模糊模型描述的不确定非线性系统 ,应用二次 D-稳定概念 ,对给定复平面上的某一D域提出模糊系统全局鲁棒 D-稳定的充分条件 ,基于并行分布补偿 (PDC)技术 ,各局部状态反馈镇定控制器设计归结于解一组耦合线性矩阵不等式 (L MI) ,全局控制器通过隶属度函数由各局部控制器混合而成 ,并以此保证整个系统的鲁棒 D-稳定性。最后用质量弹簧阻尼系统给出了仿真示例。     

多输入多输出非线性多时滞系统的直接自适应模糊跟踪控制

针对多输入多输出非线性多时滞系统,提出了一种直接自适应模糊跟踪控制方案．该方案有机综合了自适应控制和H∞ 控制,构建了一种自适应时滞模糊逻辑系统用来逼近有多重时滞的未知函数;设计了H∞ 补偿器来抵消模糊逼近误差和外部扰动．根据跟踪误差给出了参数调节规律,构造了包含时滞的李亚普诺夫函数,从而证明了误差闭环系统满足期望的H∞ 跟踪性能．仿真结果表明了该方案的可行性．     

Robust control of systems with fuzzy representation of uncertainties

In this paper, an approach is proposed to design robust controllers for uncertain systems with the linguistic uncertainties represented by fuzzy sets. With a provided technique, the fuzzy sets are best approximated by intervals (crisp sets). Then the Kharitonovs theorem is applied to construct a robust PID controller for the uncertain plant with time-invariant uncertainties represented by interval models. Also, for the uncertain system with linguistic values of the time-varying uncertainties best approximated by intervals (which are bounded), a robust sliding mode controller is developed to stabilize the uncertain system if the sliding coefficient conditions are satisfied. Moreover, the best approximation intervals are shown to be more related to the possibility distribution of the elements in the universes of discourse of fuzzy sets than the type of membership functions used for fuzzy sets. Examples and simulation results are included to indicate the design approach and the effectiveness of the proposed robust controller.This work is partly supported by the the R.O.C. National Science Council through Grant NSC 90-2213-E-197-002.     

Adaptive fuzzy output-feedback control for a class of nonlinear pure-feedback systems with time delays

This paper investigates observer-based adaptive fuzzy control for a class of delayed nonlinear systems in pure-feedback form. We first proposed a linear observer to get the estimation of the system's state. And then utilise fuzzy logic systems to model those nonlinearities. Further, adaptive fuzzy approach and backstepping technique are combined to develop the desired controller via Lyapunov analysis. The suggested adaptive fuzzy control scheme ensures that all the signals of the resulting nonlinear system converge to a small neighbourhood of the origin. Then a real simulation is used to illustrated the effectiveness of our results.     

基于矩阵测度的非线性广义时滞系统鲁棒模糊控制

研究T-S模糊广义时滞系统的鲁棒控制问题.不同于传统的寻求公共正定矩阵的方法,基于矩阵测度给出保证系统鲁棒稳定的充分条件,并将此条件进一步转化为线性矩阵不等式.通过求解线性矩阵不等式,得到状态反馈控制器和静态输出反馈控制器.最后通过算例仿真验证了方法的有效性.     

Robust stability of homogeneous large-scale bilinear systems with time delays and uncertainties

This paper addresses the problem of stability analysis for homogeneous large-scale uncertain bilinear time-delay systems subjected to constrained inputs. Both nonlinear uncertainties and interval systems are discussed. Several delay-independent criteria are presented to guarantee the asymptotic stability of the overall systems. The main feature of the presented criteria is that although the Lyapunov stability theorem is used, they do not involve any Lyapunov equations that may be unsolvable. Three illustrative numerical examples are presented to verify the effectiveness of the proposed stability criteria.     

Non-monotonic robust H2 fuzzy observer-based control for discrete time nonlinear systems with parametric uncertainties

A non-monotonic Lyapunov function (NMLF) is deployed to design a robust H₂ fuzzy observer-based control problem for discrete-time nonlinear systems in the presence of parametric uncertainties. The uncertain nonlinear system is presented as a Takagi and Sugeno (T–S) fuzzy model with norm-bounded uncertainties. The states of the fuzzy system are estimated by a fuzzy observer and the control design is established based on a parallel distributed compensation scheme. In order to derive a sufficient condition to establish the global asymptotic stability of the proposed closed-loop fuzzy system, an NMLF is adopted and an upper bound on the quadratic cost function is provided. The existence of a robust H₂ fuzzy observer-based controller is expressed as a sufficient condition in the form of linear matrix inequalities (LMIs) and a sub-optimal fuzzy observer-based controller in the sense of cost bound minimization is obtained by utilising the aforementioned LMI optimisation techniques. Finally, the effectiveness of the proposed scheme is shown through an example.