Observer-based fault detection for nonuniform sampling systems

This paper is concerned with robust fault detection filter (RFDF) design problem for a class of nonuniform sampling systems, where the sampling interval is time-varying within a certain known bound. First, the system is transformed into a time-varying discrete time system, where time-varying parts due to the sampling interval variation are treated as norm bounded uncertainties based on robust control techniques. Then design of the optimal reference residual generator is formulated as an H_∞ model-matching problem. The existence condition of the robust fault detection filter for nonuniform sampling systems is presented in terms of linear matrix inequality(LMI) applying robust H_∞ optimization control technique. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed method.