Using energy constraints to generate fault candidates in model based diagnosis

The authors demonstrate the use of qualitative modelling techniques for the fault diagnosis of continuous dynamic systems. In addition, they examine the various classes of models of physical systems and their usages within a functional perspective of `model-based´ diagnosis. They outline a scheme for fault diagnosis which integrates the application of multiple models, qualitative and numeric, of the correctly operating and the faulty system. A simulation model of an industrial heat exchanger has been developed and used as a platform to validate the proposed diagnosis scheme. This is briefly described. The results of the model-based diagnosis scheme are presented. Finally, the paper concludes with remarks on the effectiveness of the use of qualitative models in model-based diagnosis and its future extensions