Impact Assessment and Mitigation of Cyber Attacks on Frequency Stability of Isolated Microgrid Using Virtual Inertia Control

The reliance of smart grids on modern communication infrastructure has increased the risk of cyber attacks in modern power systems. Time delay attack is a form of cyber attack that can have drastic effect on the frequency stability of power systems with high penetration of renewable energy sources because of the reduction in overall inertia of the power system. In this paper, a new virtual inertia control strategy that augments the conventional virtual inertia strategy with a virtual damper to reduce the impacts of time delay attacks on the load frequency control loop of the isolated microgrid is proposed. During time delay attack -when the frequency measurement from the phase measurement unit is delayed by an adversary, the proposed strategy provides better frequency control response with reduced oscillations and frequency deviation nadirs, thereby improving the security and stability of the microgrid.