Load frequency resilient control of power system against delayed input cyber attack

Nowadays the industrial control systems (ICS) like smart grids involve the IT infrastructure as well as open communication networks. This makes the smart grids vulnerable to cyber attacks which can cause a heavy impact on human life and economy as well. Here, we consider time-delay-switch (TDS) attack on the load frequency control (LFC) of smart grid. TDS attack can destabilize the power system because the adversary introduces the delays in the control signal communication channel of the LFC system. TDS attack on control channel is also termed as delayed input attack. To counter this adverse situation, linear matrix inequality (LMI) based H∞ resilient controller is designed by utilizing the Lyapnov-Krasovskii (LK) functional based delay-dependent stability criteria. The effectiveness and resilience of the designed controller is verified by the numerical simulation on the linear time invariant (LTI) model of LFC for two-area power system.