Decentralized Secure Load Frequency Control for Multi-Area Power Systems Under Complex Cyber Attacks

This paper investigates the problem of decentralized secure load frequency control (LFC) for multi-area power systems (MAPSs) under complex cyber attacks launched by a malicious attacker. Firstly, a novel model is developed, encapsulating complex cyber attacks comprising both Denial of Service (DoS) attacks and deception attacks. These sophisticated attacks possess compound characteristics across the time and spatial domains. This implies that a single area within an MAPS may face diverse cyber attacks at different times, while different areas within the same MAPS might experience varying attacks simultaneously. To reflect real-world scenarios, we consider the malicious attacker alternating between active and sleep modes. In the active mode, the attacker randomly launches either DoS attacks or deception attacks. In the sleep mode, no attacks are executed. Secondly, a decentralized secure LFC scheme is devised to mitigate the detrimental impact of complex cyber attacks. The mean-square exponential stability of the closed-loop system with a prescribed $H_{\infty }$ performance level is established using Lyapunov stability theory and the switching system method. Moreover, the control gain matrices are determined through the linear matrix inequality technique. Finally, the effectiveness of the proposed method is verified by an IEEE 39 bus test system.