【摘要】 该文研究了一类含有未知输入干扰和模型不确定性的线性时滞系统的故障诊断问题。通过设计自适应诊断观测器,得到了一种新型的鲁棒执行器故障诊断方法。首先针对确定性系统分别设计了检测观测器和自适应诊断观测器,前者能够检测出故障的发生,后者能够理想地估计出故障随时间变化的形状。然后考虑系统的外部干扰和模型不确定,改进了自适应诊断观测器的算法,证明了故障诊断系统的稳定性,提高了故障诊断系统的鲁棒性。最后给出了故障检测过程中阈值的选取原则。仿真结果表明算法具有良好的诊断性能。更多还原

【Abstract】 The problem of!fault diagnosis for time-delay system with unknown disturbance and model uncertainty is investigated. This paper presents a novel approach for the actuator fault diagnosis of time-delay systems by using an adaptive observer technique. At first, systems without model uncertainty are initially considered: a fault detection observer and a fault diagnosis observer are designed respectively. The former can detect the fault and the latter can diagnose the fault. Followed by a discussion of a general situation where the system is subjected to either model uncertainty or external disturbance, an adaptive diagnostic algorithm is developed to diagnose the fault, and a modified version is proposed for general system to improve robustness. The stability of fault diagnosis systems is proved. Finally, the selection of the threshold for fault detection is also discussed. A numerical example is given to illustrate the efficiency of the proposed method.更多还原