Design and Defense of Modal Resonance-Oriented Cyber-Attack Against Wide-Area Damping Control

Most existing cyber-attacks are steady state-oriented attacks, not dynamic ones. Moreover, dynamic modal interaction between cyber layers and physical layers is not considered in current studies. This paper firstly proposes a novel modal resonance-oriented cyber-attack (MROCA) against wide-area damping control (WADC). MROCA, as a dynamic cyber-attack, analyzes the signal sent to WADC in the cyber layer and then estimates the critical oscillation mode of the physical layer without acquiring the system parameters. Then MROCA is designed to stimulate the open-loop modal resonance between the virtual oscillation mode of MROCA and the critical mode of the physical layer, thereby degrading the stability of cyber-physical power systems (CPPSs). Furthermore, the connection between MROCA and typical cyber-attacks is investigated, and the impact of MROCA on the stability of CPPSs is quantified by the modal movement with respect to the parameters of MROCA. Additionally, the corresponding defense strategy is proposed to inject the signal corresponding to the reverse mode of MROCA, thereby offsetting the negative impact of attacks. Finally, the proposed work is tested in the IEEE 39-bus benchmark system and the practical provincial power system. Simulation results indicate that the proposed MROCA will excite the open-loop modal resonance and reduce the stability of CPPS. The proposed defense strategy can accurately estimate the injected mode signal and ensure system stability when the system is attacked by MROCA.