一种含扰动非线性离散系统的故障观测器设计方法

A Fault Observer Design Method for Nonlinear DiscreteSystems with Disturbance

针对一类含扰动、传感器故障和执行器故障的非线性离散系统,提出了一种新型的故障观测器设计方法,该方法既考虑到了故障的类型,又考虑到了故障估计误差的收敛速度,故障估计方法适用性更强。首先,构造出含系统状态和传感器故障的增广向量,得到一个等价的广义系统;其次,考虑到系统中的执行器故障及故障估计的速度,构建同时含系统状态、执行器故障和传感器故障的故障观测器,并给出故障观测器存在的充分条件;最后,通过某飞机的纵向运动系统等非线性离散系统模型,对增广状态向量进行鲁棒估计,故障估计结果验证了该方法的优越性。

A novel fault observer design method is proposed for a class of nonlinear diserete systems withdistubances,sensor faults,and actuator faults.This method considers both the type of faults and the convergencerate of fault estimation errors,making the fault estimation method more applicable.Firstly,an augmented vectorcontaining system states and sensor faults is constnucted to obtain an equivalent generalized system.Secondly,considering the actuator faults in the system and the speed of fault estimation,a fault observer is constructedthat inchudes system state,actuator faults,and sensor faults,and the sufficient conditions for the existenceof the fault observer are given.Finally,a nonlinear discrete system model such as the longitudinal movementsystem of an aircraft is used to estimate the augmented state vector robustly,and the fault estimation resultsverify the superiority of the proposed method.