Fault Diagnosis Using Adaptive Observer Based Techniques

Abstract

This paper presents a novel robust adaptive observer based approach for the actuator fault diagnosis in dynamic systems which are expressed by a state space model and are subjected to structured model uncertainties, external disturbances and dynamic uncertainties. An adaptive observer, whose adaptive tuning part only involves the estimation of the fault, is initially constructed to demonstrate the possibility of using adaptive updating rules to estimate the fault This is followed by a description of how to select a fixed observer gain matrix in order to make the resulting adaptive observer sensitive to the fault and insensitive to the model uncertainties and external disturbances. The method is demonstrated through its application to the monitoring of a simulated distillation column.