【作者】 张显；

【导师】 唐功友；

【作者基本信息】 中国海洋大学 ， 计算机软件与理论， 2010， 硕士

【摘要】 针对应用中常见的时滞系统以及系统中最常见的一类传感器和执行器故障本文研究含测量时滞系统的故障诊断问题。首先综述了故障诊断和控制的国内外研究现状,介绍了时滞系统的故障诊断制成果。然后利用最优理论、对偶原理、线性矩阵不等式及状态观测等技术,提出了在系统中含有不时滞情况下的故障诊断和容错控制方法。本文的研究内容概括如下。1.对带有故障的线性系统模型进行了描述,并对本文所研究的一类已知动态特性未知初始状态和初始时刻的故障信号用“外系统”的概念和状态空间模型进行了建模。将故障视为一个增广系统的状态,可以将故障诊断问题转换为状态观测问题。然后根据系统执行器故障和传感器故障特征值的不同情况,以及故障模型的两种不同情况,利用可观性的PBH特征向量判据给出了不同情况下相应的故障可诊断的判别条件。2.针对含测量时滞的线性系统,通过线性变换将时滞系统转化为无时滞系统,然后将故障状态转化为增广系统的状态,构造了基于观测器的增广系统故障诊断器,利用Lyapunov稳定性理论和线性矩阵不等式技术,实现了系统的实时在线故障诊断。3.研究了线性时滞系统的故障诊断方法。给出并证明了线性时滞系统发生此类故障时故障可诊断性的充分条件。提出了一种无时滞转换方法,将时滞系统转化为形式上不含时滞的系统,从而解决测量时滞系统的故障诊断问题。然后通过最优控制理论和对偶原理,提出了一种新的的最优故障诊断器的设计方法,使之能够满足一定的二次型性能指标。从而在实现在线故障诊断的同时使所设计的故障诊断器实现最优。更多还原

【Abstract】 This dissertation studies the problems on fault diagnosis for systems with delayed mesurement to solve a class of usual actuator and/or sensor faults. At firstly, the history of the development on the fault diagnosis is reviewed. The latest research tendency and the main methods are summarized in the fault diagnosis domain, and the fault diagnosis approaches are introduced for time-delay systems. Then, by using optimal control theory, duality principle, linear matrix inequation, and state observer and so on technology, fault diagnosis approaches are proposed for systems with delayed mesurement. The major results of this dissertation are summarized as follows.1. On a class of linear system with the fault model is described, and the model is established with the concept of "exosystem" and the state space expression for this class of faults with known dynamic characteristics and unknown initial time and initial state. We regard the fault states as the sub-states of an augmented system, the fault diagnosis problem can be converted to state observation. Then according to the different eigenvalues of system actuator failures and sensor failures, as well as two different situations fault model, according to the PBH eigenvector criteria of observability, we obtain the fault can be diagnosed criterion appropriate in different situations.2. The problems of fault diagnosis for systems with delayed measurements are considered. A functional transformation is first presented, which transforms the system with delayed measurements into a system without delay formally. Then the fault states are transformed into the states of an augmented systerm, and design of the observer-based diagnoser is proposed. Finally, by using the Lyapunov stability theory and liner matrix inequality(LMI) technology, the real-time fault diagnosis is realized on-line.3. Studies the problem of fault diagnosis for systems with delayed measurements when there exist sensor and actuator faults. The main contribution consists in the delay-free transformation approach for measurement delays and in the design of a new optimal fault diagnoser. Firstly, we regard the fault states as the sub-states of an augmented system, and a delay-free transformation is proposed to transform the system with delayed measurement vector into a delay-free one. Then a sufficient condition of the observability is proved for the transformed system. By using duality principle, the design problem of the optimal fault diagnoser is transformed into an equivalent optimal control problem for the duality system of the fault diagnosis error equation. Finally, the real-time fault diagnosis is realized by constructing a new reduced-order optimal fault diagnoser.4. The conclusions are made.And the direction for the future study is indicated.更多还原