Fault estimation and accommodation for networked systems based on intermediate variable with intermittent DoS attacks

In this paper, the problem of fault estimation(FE) and fault-tolerant control is considered for networked systems under intermittent denial-of-service(DoS) attacks. Under the influence of DoS attacks, some measurement information via the communication network is unavailable, which makes some existing FE methods unusable. By introducing an intermediate variable containing the system state information and fault information, the observer to accurately estimate the fault and state of the system is proposed. By introducing a switching FE design method, the information that cannot be updated due to DoS attacks is discarded. The gain matrices of the FE observer and fault-tolerant controller are calculated simultaneously by solving two linear matrix inequalities. Compared with the existing results, the proposed FE strategy does not require the system to match observer matching conditions. Finally, the simulation example shows the effectiveness of the proposed method.