Robust H∞ fault detection filter for networked control system with network-induced uncertainties

Abstract

A robust fault detection filter (RFDF) design problem for networked control system (NCS) is investigated in this note. Network-induced uncertainties including time-varying unknown network-induced delay and data packet dropout are assumed to be existing in both sensor-to-controller link and controller-to-actuator link, where the total network-induced delay is transformed into uncertainty of system model, and the data packet dropout is described as a two-state Markov chain. Then, the closed NCS with network-induced uncertainties is modeled as a Markovian jump system with model uncertainty. An observer-based fault detection filter is presented as a residual generator and a performance index is proposed to deal with the robustness issues, which is to enhance the robustness of the residual generator against network-induced uncertainties and disturbances, without significant loss of the faults sensitivity. Sufficient condition for asymptotically mean-square stable of residual dynamics is derived, and the desired RFDF is obtained, which is constructed in terms of certain linear matrix inequality. Finally, a numerical example illustrates the effectiveness of the proposed approach.