Active fault isolation of nonlinear systems

This work considers the problem of designing an active fault isolation scheme for nonlinear systems subject to uncertainty. The key idea is to utilize the control action to drive the system to a region which allows isolation of faults not otherwise possible under nominal operation. To this end, dedicated residuals are generated for the faults under consideration. To make these residuals sufficiently sensitive, a switching rule is designed to drive the system, upon fault detection, to move towards a point that, for any given fault, results in the reduction of the effect of other potential faults on the evolution of a system state. A simulation example of a chemical reactor is used to illustrate the effectiveness of the proposed method.