Impact of Malicious SCADA Commands on Power Grids' Dynamic Responses

Control-related attacks can use malicious commands crafted in legitimate formats to initiate perturbations to power systems. Our previous work used the steady state of power systems (e.g., through power flow analysis) to estimate the consequences of such commands [1]. However, when power systems move from one steady state to another, their physical components go through a transient period, during which the system state can experience oscillations. An anomaly in an oscillation can make power systems lose synchronisms and experience catastrophic consequences. Analysis based on the steady state cannot understand and predict those harmful oscillations. In this paper, we study the impacts of control-related attacks on the dynamic responses of a power grid, by mapping malicious commands (e.g., that disconnect transmission lines) delivered via communication networks to power systems' electromechanical models. Based on theoretical analysis and numerical simulations, we find that it is challenging for attackers to destabilize a power system, but they can introduce large oscillations in the transient period and thereby cause physical damage.