Mitigation of frequency disturbance in power systems during cyber-attack

This article investigates the impact of cyber-attack on a power station in frequency disturbing aspects during sudden changes of load of the system and proposes a solution method to make it stable. Stable limit of the speed regulation for load frequency control (LFC) and integral controller gain for automatic generation control (AGC) is derived from their characteristic equations. Depending upon the nature of cyber-attack (positive biased or negative biased attack) simulations are performed to show the frequency deviations and oscillations of the power system. Finally a feedback LFC block with a three input switch is designed to remove these oscillations.