Power Grid State Estimation under General Cyber-Physical Attacks
This addresses the critical need for damage assessment in power grids under general attacks, but it is incremental as it builds on prior work by relaxing the connectivity assumption.
The paper tackles the problem of power grid state estimation under cyber-physical attacks that can partition the grid into islands, proposing a linear programming-based algorithm that accurately recovers link status under certain conditions, with numerical evaluations on the Polish power grid showing high accuracy in localizing failed links.
Effective defense against cyber-physical attacks in power grid requires the capability of accurate damage assessment within the attacked area. While some solutions have been proposed to recover the phase angles and the link status (i.e., breaker status) within the attacked area, existing solutions made the limiting assumption that the grid stays connected after the attack. To fill this gap, we study the problem of recovering the phase angles and the link status under a general cyber-physical attack that may partition the grid into islands. To this end, we (i) show that the existing solutions and recovery conditions still hold if the post-attack power injections in the attacked area are known, and (ii) propose a linear programming-based algorithm that can perfectly recover the link status under certain conditions even if the post-attack power injections are unknown. Our numerical evaluations based on the Polish power grid demonstrate that the proposed algorithm is highly accurate in localizing failed links once the phase angles are known.