基于增广观测器的非线性系统执行器故障诊断

针对一类满足李普希茨条件的非线性系统，提出了一种新的执行器故障诊断方法。将执行器故障作为增广状态向量的一部分构造一个增广系统，然后利用线性矩阵不等式方法设计一个增广状态观测器，能够同时获得原系统的状态和执行器故障的渐近估计。利用李亚普诺夫理论分析了增广状态观测器的稳定性和收敛性。最后，将所提出的方法用于卫星姿态控制系统执行器的故障诊断，仿真结果验证了该方法的有效性。

Augmented Observer Based Actuator Fault Diagnosis for Nonlinear Systems#br#

An actuator fault diagnosis approach is proposed for linear systems and a class of nonlinear systems with Lipschitz constraints.Considering the actuator fault as an auxiliary state vector, an augmented system is constructed. And then an augmented state observer is designed by the linear matrix inequality technique. The asymptotic estimates of the original system state vector and the actuator fault term are obtained simultaneously. Stability and convergence of the proposed observer is analyzed based on the Lyapunov theory. Finally, the proposed approach is applied to actuator fault diagnosis for the satellite attitude control system. Simulation examples illustrate the effectiveness of the presented method.