基于微分同胚变换的故障重构算法

Fault reconstruction based on global diffeomorphic coordination transformation

针对一类含有未知输入扰动的不确定非线性系统提出一种鲁棒故障重构方案.采用全局微分同胚变换,将非线性系统变换为二个子系统,使得其中一子系统不受故障影响,状态部分可观,另一子系统受故障影响但状态完全可观.利用滑模变结构原理对两个子系统分别设计状态观测器消除扰动对系统的影响后,再利用等值控制方法实现对故障的重构.应用案例验证了所提方法的有效性.

A robust fault diagnosis is presented for a class of uncertain nonlinear systems with unknown input disturbances.The system is transformed into two subsystems by means of the global diffeomorphic coordination transformation.One of the subsystems is free from faults whose states can be partially measured,while the other is subject to faults and all its states can be measured.In order to eliminate the effects of unknown disturbances,state observers are subsequently constructed for both subsystems based on the sliding mode variable structure theory,thus the studied system acquires its ability of reconstructing fault by applying the specific equivalent control methodology.Simulation examples demonstrate the effectiveness of the proposed design.