Optimal auxiliary input for fault detection based on Kullback divergence

The introduction of an auxiliary input may be useful to detect system faults quickly without affecting the original system behavior in normal mode. Such an auxiliary input is designed to enlarge the distance between the system models corresponding to the normal and fault modes. The distance can be measured by the Kullback divergence. This paper deals with the optimal design of the auxiliary for the fault detection of dynamical systems. Numerical simulation results indicate the applicability of the proposed auxiliary input in fault detection.