Fault detection for networked control systems via reduced-order filtering

For the networked control system (NCSs) with short network-induced time delay, the online fault detection method is proposed. The Markov jumping model for NCSs is established under the condition that the network-induced time delay can be governed by the Markov chain. The feasible solution of the reduced order fault detection filter is achieved based on the robust filtering method, and the non-convex optimization problem with the constraint of matrix rank is obtained. The local optimal solution of the optimization problem is considered based on the alternating projection method and the parameters of the fault detection filter are presented. Finally, the numerical examples show that the proposed approach can restrain the impact of the delays, and detect the faults quickly and effectively.