Event-Triggered Distributed Attack Detection and Fault Diagnosis

This article investigates the security issue for multiagent systems (MASs). Due to the effect of physical faults and cyberattacks, MASs are prone to anomalies. To meet these challenges, an observer-based distributed attack detection and fault diagnosis scheme is proposed. First, to reduce unnecessary communication loss, an event-triggered mechanism is designed for each agent to determine whether to transmit the current measurement to its own state estimator and its neighbors. Then, based on the information received from neighbors, each agent designs a bank of attack detectors based on unknown input observer for the neighbors to detect whether there are attacks in the communication with the neighbor agents. In addition, for each agent, according to the local measurement and the estimated states of adjacent agents, a fault diagnoser based on the Luenberger observer is designed, which can be combined with the attack detectors to make the distributed fault diagnosis for each agent. Finally, the effectiveness and scalability of the proposed scheme are verified by applying it to two smart grids with multiple generators.