Impact of cyber-attack on isolated power system

In this modern era of civilization demand of electricity from interconnected grid system is increasing day by day. That is why improving the reliability of the power system has become the main concern to the experts. This article investigates the impact of cyber-attack on an isolated power station in frequency disturbing aspects during sudden changes of load of the system. 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 attack or negative biased attack) simulation curves are developed to show the frequency deviations and oscillations of the power system. Most severe attack is also characterized to protect power system from unstable situation.