一类非线性系统的鲁棒故障诊断

Robust fault diagnosis of a class of nonlinear systems

基于未知输入观测器设计和等价控制的概念,讨论了一类非线性系统传感器故障的鲁棒故障诊断问题.首先引入若干积分变量对该类非线性系统进行扩维;然后针对扩维后的系统设计基于变结构的未知输入观测器;最后,由等价控制的概念直接重构得到传感器故障.仿真结果表明等价控制能够较好地重构传感器故障.

Based on the unknown input observers and the concept of equivalent control, this paper considers the problem of robust fault diagnosis of sensor faults in a class of nonlinear systems. To begin with, this kind of systems can be augmented into a higher order system by introducing some integral variants. Then a variable structure based unknown input observer can be constructed for the augmented system. At last, the sensor faults can be recovered directly by the concept of equivalent control. Numerical simulation shows the effectiveness of the recovery of the senor faults using the concept of equivalent control.