模型不确定性线性系统的鲁棒故障检测滤波器设计

基于给定的性能指标函数, 将受模型不确定性和范数有界未知输入影响的线性不确定系统的基于观测器的鲁棒故障检测滤波器设计问题归结为H_∞ 优化问题, 并通过选取适当的后置滤波器和观测器增益矩阵, 使产生的残差达到对于未知输入和模型不确定性的鲁棒性与对于故障的灵敏度的最佳均衡. 简例验证了本文提出算法的有效性.     

基于观测器的不确定时滞系统的鲁棒控制

研究不确定线性时滞系统的状态观测器和基于观测器的鲁棒控制器设计问题,其中不确定性是时变的、不要求满足匹配条件。通过构造增广系统,利用Ｌｙａｐｕｎｏｖ稳定性理论,获得了该不确定系统存在状态观测器和基于观测器的鲁棒控制器的充分条件,同时给出了相应的状态观测器和基于观测器的鲁棒控制器。所得结论推广并改进了已知的一些结果,并通过实例说明了其有效性。     

Event-triggered simultaneous fault detection and tracking control for multi-agent systems

The main aim of this study is to design distributed simultaneous fault detection and control units for multi-agent systems subject to limited communication and energy resources. For this purpose, each agent is equipped with a single module that generates both the residual signal for the fault detection task, as well as the control input of each agent for the tracking objective. To reduce the communication among the agents, an event-triggered data transmission paradigm is considered by using a dynamic triggering rule which results in higher data transmission reduction in comparison with the static triggering condition. Moreover, the proposed dynamic observer-based structure for the detector-controller module provides more degrees of freedom compared to the static Luenberger observer. The design parameters are obtained by solving a multi-objective optimisation problem considering the fault detection, tracking, and communication objectives. Simulation results illustrate the effectiveness and capabilities of the proposed method.     

基于观测器的非线性不确定系统鲁棒故障检测新方法

针对非线性不确定系统的鲁棒故障检测问题,提出了一种采用统计理论的新方法.通过设计全阶故障观测器产生残差信号,将鲁棒故障检测观测器设计问题转化为H∞优化问题;利用H∞范数描述故障检测的鲁棒性,保证系统的抗干扰能力,同时引入H_范数,确保对故障信号的灵敏度;应用线性矩阵不等式技术给出了该设计问题解存在的条件和求解方法.将统计理论用于故障检测阈值的确定,充分考虑了残差信号的随机特性,使故障决策更加准确和可靠.最后通过仿真实例验证了本文方法的有效性.     

On-line fault detection in uncertain nonlinear systems using diagnostic observers: a survey

The paper discusses the principles of model-based fault detection and isolation (FDI) in nonlinear and time-varying uncertain dynamic systems. Such systems are typical for such complex plants as, for example, in the chemical process industries or in advanced transportation technology. For a model-based fault diagnosis in such situations, robust or even adaptive strategies are needed. In this paper the theory of robust linear observer-based residual generation for FDI is reviewed from a general point of view. The structural equivalence between the parity space approach and observer-based approach is shown in a new simple graphical way by showing that the observer-based FDI concept can easily be transformed into an equivalent extended parity space configuration, without claiming, however, equivalence of the underlying design techniques. The unknown input observer approach known as a most powerful and comprehensive framework for robust residual generation for FDI in uncertain linear systems is extended to classes of nonlinear and time-varying systems. For such plants an adaptive nonlinear unknown input observer scheme is proposed. Finally, appropriate residual evaluation techniques are outlined and suggestions are made to increase the robustness, for instance by using adaptive thresholds.     

基于观测器的时滞系统鲁棒控制器的设计

研究了一类不确定时滞系统基于观测器的鲁棒镇定问题，系统的不确定性时变未知且范数有界，目的是设计状态观测器和线性无记忆观测状态反馈控制器，使其能够镇定一类状态和控制输入不确定性时滞系统。基于Lyapunov稳定性理论，采用线形矩阵不等式这一有效工具，给出了系统基于观测状态反馈鲁棒镇定的充分条件，并且利用线形矩阵不等式的解构造了使得系统鲁棒稳定的基于观测状态反馈控制器，所得结果与时滞相关，从而相对减弱了控制器设计的保守性。数值算例表明了所提出的设计方法的有效性。     

一种故障检测滤波器的多目标优化设计方法

提出一种基于观测器的故障检测滤波器的非凸多目标优化设计方法.针对线性时不变动态系统,构建一个由输出观测器和后滤波器组成的故障检测滤波器,将其残差动态特性描述为非凸的双线性矩阵不等式形式.利用双线性矩阵不等式中可完全平方非正定项的上界替代原非正定项,将双线性矩阵不等式转化为一组线性矩阵不等式,进而获得多目标优化问题的可解条件以及观测器增益与后滤波器矩阵的求解方法.仿真算例说明了算法的有效性.     

一种鲁棒故障检测与分离的参数化方法

针对具有未知干扰输入的多变量线性系统，提出一种鲁棒故障检测与分离的完全参数化方法。利用最近的结果，基于Luenberger未知输入观测器矩阵的特征值及一组自由参数向量，分别给出了系统干扰解耦和故障分离的充要条件。通过适当选择满足一些约束的自由参数，仅使用单一观测器实现了鲁棒故障检测与分离设计。该方法提供了所有设计自由度。一个数值例子证明了该方法的有效性。     

Unknown Input Fault Detection and Isolation Observer Design for Neutral Systems

This paper deals with actuator fault diagnosis of neutral delayed systems with multiple time delays using an unknown input observer. The main purpose is to design an observer that guarantees the asymptotic stability of the estimate error dynamics and the actuator fault detection. The existence conditions for such an observer are established. The main problem studied in this paper aims at designing observer‐based fault detection and isolation. The designed observer enhances the robust diagnosis performance, including rapidity and accuracy, and generates residuals that enjoy perfect decoupling properties among faults. Based on Lyapunov stability theory, the design of the observer is formulated in terms of linear matrix inequalities, and the diagnosis scheme is based on a bank of unknown input observers for residual generation that guarantees fault detection and isolation in the presence of external disturbances. A numerical example is presented to illustrate the efficiency of the proposed approach.