Intermittent Fault Detection and Isolation for Discrete System with Unknown Disturbance Based on Interval Observer

In this paper, the problem of intermittent fault diagnosis for linear discrete systems subjected to unknown disturbance is studied. An interval observer for fault diagnosis is designed, residual evaluation and threshold setting are not required, and the upper and the lower bounds of the residual generated by the interval observer can be directly used as adaptive thresholds for the intermittent sensor fault detection. In order to locate the faults, a set of interval isolation observers is designed to isolate sensor faults. Finally, a simulation example is presented to demonstrate the effectiveness of the proposed diagnosis scheme.