不确定系统的鲁棒容错H∞控制

针对不确定线性连续系统,研究了执行器失效情况下的鲁棒容错H∞控制问题.利用LMI,给出了不确定线性系统对任意执行器故障均保持渐近稳定且满足给定干扰衰减指标的鲁棒容错H∞控制器存在的充要条件,讨论了参数不确定线性系统的鲁棒容错H∞控制器的设计问题.根据凸优化理论,进一步给出了鲁棒容错最优H∞控制器的线性凸优化设计算法和设计步骤.采用所设计的状态反馈控制器,当任意执行器出现故障时,闭环系统仍保持渐近稳定且满足给定的干扰衰减性能指标.数值仿真例子验证了该设计方法的可行性和有效性.     

时滞依赖型区间时滞系统非脆弱H_∞控制

针对一类状态和控制输入矩阵均为区间矩阵的不确定时滞系统,其中状态和控制输入同时具有未知但有上界的时间滞后,基于Lyapunov稳定性理论,利用线性矩阵不等式(LMI)方法,讨论了该类时滞系统的时滞依赖型非脆弱H∞状态反馈控制器设计问题.在区间不确定性和控制器执行机构扰动均满足增益有界条件下,得到了该类时滞系统的满足H∞性能的一个充分条件.通过求解一个线性矩阵不等式(LMIs)组,即可获得鲁棒H∞控制器.最后对某型飞机作机动飞行仿真,仿真结果表明该鲁棒控制器设计方法是有效的.     

一类非线性不确定时滞系统的记忆与无记忆复合H∞状态反馈控制

针对一类具有状态非线性不确定性的线性时滞系统,基于Lyapunov稳定性理论,利用线性矩阵不等式（LMI）方法,讨论了该类时滞系统的记忆与无记忆复合H∞状态反馈控制器的设计问题。在非线性不确定性满足增益有界条件下,得到了该类时滞系统的满足鲁棒H∞性能的一个充分条件。通过求解一个线性矩阵不等式-LMI,即可获得鲁棒H∞控制器。     

一类时变输入时滞不确定系统的鲁棒控制器设计

针对一类具有时变输入时滞的不确定系统,基于Lyapunov-Krasovskii方法,讨论了该类系统鲁棒控制器的设计问题.在不确定性满足范数有界条件下,给出了时滞相关的鲁棒可镇定充分条件及相应的鲁棒控制器设计方法,利用辅助变量和广义状态证明了闭环系统的渐近稳定性.最后,进行了数值仿真,结果证明了该方法的有效性和优越性.     

输入受限下的四旋翼无人机鲁棒容错控制

针对四旋翼无人机(UAV)在输入受限情况下的执行器故障和干扰问题,提出了一种鲁棒容错控制方法.首先建立了包含执行器故障、输入受限以及外界干扰的四旋翼UAV位置模型和姿态模型;然后分别对位置环和姿态环进行了分析,采用滑模滤波器对虚拟控制指令滤波,并利用模糊系统逼近法估计出不确定项,设计了鲁棒容错控制律;最后证明了位置环和...     

一类时滞不确定非线性系统的自适应鲁棒H∞控制

本文针对一类同时具有未知上界时滞不确定性和外部扰动的非线性系统，在非线性H∞控制的理论框架内讨论了系统的自适应鲁棒H∞控制问题，通过自适应律估计时滞不确定性的上界，并且基于Lyapunov-Krasovskii函数和Hamilton-Jacobi不等式获得使鲁棒控制问题可解的自适应鲁棒控制器。     

一类不确定关联时滞系统的可靠保性能鲁棒控制

针对一类具有参数不确定性、非线性扰动和多时变时滞的关联系统,采用[0,σ]故障模型,提出了考虑执行器故障的可靠保性能鲁棒控制问题。基于Lyapunov函数和线性矩阵不等式（LMI）方法,得到系统存在可靠保性能控制器的充分条件和控制器的设计方法,并给出了系统的可保性能的表达式。     

一类线性不确定切换系统的非脆弱控制器设计

针对一类线性不确定切换系统,利用公共Lyapunov函数的方法,给出了当所设计的控制器存在加性摄动时鲁棒非脆弱控制器存在的条件。该控制器能够保证闭环切换系统在任意切换律下渐近稳定。然后应用线性矩阵不等式将鲁棒非脆弱控制器的设计问题转化为一组线性矩阵不等式的可行解问题,从而可借助Matlab中的LMI工具箱直接求解。最后通过仿真算例验证所提方法的有效性。     

输入饱和约束下一类多智能体编队系统鲁棒一致性分析

针对输入饱和约束奈件下具有不对称时滞的二阶多智能体编队系统的鲁棒一致性问题,本文综合利用Lya-punov-Krasovskii泛函方法和线性矩阵不等式的方法对其进行了研究.首先在n维欧氏空间中建立了二阶多智能体所组成的编队系统的数学模型;然后设计了分布式的基于一致性的具有饱和约束和不对称时滞的编队控制律;进一步,利用非线性扇区法处理了饱和项,将其转化为一种简单的非线性项,从而建立了Lyapunov-Krasovskii泛函,并利用LMI方法对编队系统进行了鲁棒一致性分析,得到了系统达到鲁棒一致时的线性矩阵不等式条件,并通过仿真分析验证了所得条件的正确性.     

基于迭代学习观测器的随机分布系统容错控制

针对包含故障和干扰的非高斯随机分布系统,提出了一种基于迭代学习观测器(ILO)的鲁棒容错控制方法.使用线性B样条神经网络建立了输出概率密度函数(PDF)和动态权重之间的关系.设计迭代学习观测器,以较小的计算量实现对故障的精确估计.利用故障估计信息设计容错控制器,使得系统的权向量在故障发生后仍能够跟踪到期望的权向量.最后...     

Exponential filtering for uncertain Markovian jump time-delay systems with nonlinear disturbances

In this paper, we study the robust exponential filter design problem for a class of uncertain time-delay systems with both Markovian jumping parameters and nonlinear disturbances. The jumping parameters considered here are generated from a continuous-time discrete-state homogeneous Markov process, and the parameter uncertainties appearing in the state and output equations are real, time dependent, and norm bounded. The time-delay and the nonlinear disturbances are assumed to be unknown. The purpose of the problem under investigation is to design a linear, delay-free, uncertainty-independent state estimator such that, for all admissible uncertainties as well as nonlinear disturbances, the dynamics of the estimation error is stochastically exponentially stable in the mean square, independent of the time delay. We address both the filtering analysis and synthesis issues, and show that the problem of exponential filtering for the class of uncertain time-delay jump systems with nonlinear disturbances can be solved in terms of the solutions to a set of linear (quadratic) matrix inequalities. A numerical example is exploited to demonstrate the usefulness of the developed theory.     

一类非线性时滞系统的鲁棒H∞滤波器设计

 研究了满足下列条件的时滞系统的鲁棒H_∞滤波问题:假设系统的参数矩阵带有不确定性,且不确定参数是时变且范数有界的.在系统的状态与输出中同时都含有非线性无穷分布时滞与离散时滞.在设计滤波器的过程中,引入了一个新的Lyapunov-Krasovskii泛函.通过线性矩阵不等式技术,提出了参数不确定时滞系统的鲁棒H_∞滤波器存在的时滞依赖条件.鲁棒H_∞滤波器可以保证带有参数不确定性的滤波误差系统是渐近稳定的,并且满足给定的H_∞性能指标.通过仿真的研究证明了该方法的有效性.     

State and Disturbance Estimator for Time-Delay Systems With Application to Fault Estimation and Signal Compensation

For a state-space time-delay system with linearly coupled input and output disturbances, a simultaneous state and disturbance estimation technique is developed. For a nonlinear state-space time-delay system with dependent input and output disturbances, a nonlinear estimator is also proposed to estimate system state and disturbance at the same time. The proposed estimator techniques are applied next to estimate system state and fault signal. Via actuator and/or sensor signal compensation, a simple and efficient fault-tolerant operation can be realized. In the developed design, no limitations and prior knowledge are required on the considered faults. Moreover, identical actuator and/or sensor switches and control gain reconstruction are not necessary. Therefore, the proposed estimation and fault-tolerant scheme is economical and convenient in practical applications. After that, the design techniques are extended to the case of systems with a class of uncoupled input and output faults. Examples and simulations given show excellent signal estimation and fault-tolerant performance.     

Robust filtering for a class of stochastic uncertain nonlineartime-delay systems via exponential state estimation

We investigate the robust filter design problem for a class of nonlinear time-delay stochastic systems. The system under study involves stochastics, unknown state time-delay, parameter uncertainties, and unknown nonlinear disturbances, which are all often encountered in practice and the sources of instability. The aim of this problem is to design a linear, delayless, uncertainty-independent state estimator such that for all admissible uncertainties as well as nonlinear disturbances, the dynamics of the estimation error is stochastically exponentially stable in the mean square, independent of the time delay. Sufficient conditions are proposed to guarantee the existence of desired robust exponential filters, which are derived in terms of the solutions to algebraic Riccati inequalities. The developed theory is illustrated by numerical simulation     

Robust $$\alpha $$-Stabilization of Uncertain Positive Takagi–Sugeno Systems with Time-Delay via Memory State-Feedback

This paper is concerned with the design of robust state-feedback controllers for uncertain positive Takagi–Sugeno systems with time-delay. The \(\alpha \)-stabilization by static state-feedback controllers with memory is investigated, taking into account the positivity and the interval uncertainties of the delayed closed-loop system into account. For this, new sufficient \(\alpha \)-stabilization conditions are established in terms of LMIs. An example illustrates of the proposed approach.     

一类不确定非线性系统变结构自适应鲁棒控制

本文针对一类不确定非线性系统,在假设系统模型参数和不确定性界都未知的情况下,提出了一个变结构自适应鲁棒控制算法,该算法在确保闭环系统稳定的前提下,在线对系统模型参数和不确定性界进行估计.最后以船舶减摇鳍非线性控制系统为例,进行了变结构鲁棒自适应控制器的设计,经仿真研究表明,所提出的算法是有效的.     

一类脉冲量为非线性函数的不确定系统的脉冲控制

由于脉冲控制系统响应速度快,有鲁棒性和抗干扰能力强等特点,被广泛研究。在实际系统中,总存在各种干扰。针对一类带有非线性扰动的不确定性系统,脉冲量为非线性函数的脉冲控制系统的稳定性,应用脉冲控制基本理论进行研究,得出了鲁棒稳定性判据,最后通过一个实例说明了所得结果。     

A New Approach to Observer-Based Fault-Tolerant Controller Design for Takagi-Sugeno Fuzzy Systems with State Delay

This paper deals with the problem of active fault-tolerant control (FTC) for time-delay Takagi-Sugeno (T-S) fuzzy systems based on a fuzzy adaptive fault diagnosis observer (AFDO). A novel fuzzy fast adaptive fault estimation (FAFE) algorithm for T-S fuzzy models is proposed to enhance the performance of fault estimation, and sufficient conditions for the existence of the fault estimator are given in terms of linear matrix inequalities (LMIs). Using the obtained on-line fault estimation information, an observer-based fast active fault-tolerant controller is designed to compensate for the effect of faults by stabilizing the closed-loop system. Simulation results of a track trail system and a nonlinear numerical example are presented to illustrate the effectiveness of the proposed method.     

Robust Stability of Discrete Bilinear Uncertain Time-Delay Systems

This paper addresses the problem of robust stability for discrete homogeneous bilinear time-delay systems subjected to uncertainties. Two kinds of uncertainties are treated: (1) nonlinear uncertainties and (2) parametric uncertainties. For parametric uncertainties, we also discuss both unstructured uncertainties and interval matrices. By using the Lyapunov stability theorem associated with some linear algebraic techniques, several delay-independent criteria are developed to guarantee the robust stability of the overall system. One of the features of the newly developed criteria is its independence from the Lyapunov equation, although the Lyapunov approach is adopted. Furthermore, the transient response and the decay rate of the resulting systems are also estimated. In particular, the transient responses for the aforementioned systems with parametric uncertainties also do not involve any Lyapunov equation which remains unsolved. All the results obtained are also applied to solve the stability analysis of uncertain time-delay systems.     

一类离散切换系统的性能分析

针对一类含有不确定性和时滞的离散切换系统,探讨了H∞性能分析问题。假设所考虑的线性不确定性具有线性分式形式,综合利用Lyapunov-Krasovskii函数和Finsler’s引理,给出判断系统满足H∞性能界γ的充分条件,并且γ的上界可以通过求解一组线性矩阵不等式获得。最后通过一个数值算例说明方法的有效性。