Robust detection and isolation of mechanical faults in processes driven by induction machines

A robust model-based technique for fault detection and isolation in electro-mechanical systems comprising induction machines is introduced. A state observer for reconstructing the magnetic flux components of the induction machine and thereby the electrical torque is used in combination with a robust state estimator for the mechanical load torque based on a model with structured uncertainties. The fault detection and isolation problem is reduced to validation/invalidation of the models representing different fault hypotheses. The practical applicability of the method is demonstrated in a simulation example