Denial-of-Service (DoS) Attacks on Load Frequency Control in Smart Grids

While open communication infrastructures are embedded into smart grids to support vast amounts of data exchange, it makes smart grids vulnerable to cyber attacks. In this paper, we investigate the effects of Denial-of-Service (DoS) attacks on load frequency control (LFC) of smart grids. In contrast with existing works, we consider the problem that how DoS attacks affect the dynamic performance of a power system. The state space model of power systems under DoS attacks is formulated as a switched system. By applying switched system theories, the existence of DoS attacks that make the dynamics of a power system unstable is proved. A two-area power system is used to conduct case studies. The dynamic performance of the power system, such as convergence and steady-state errors, is compared under different DoS attack scenarios. It is shown that the dynamic performance of the power system is affected strongly if the adversaries launch DoS attacks before the dynamics of the power system converge.