False data injection against state estimation in power systems with multiple cooperative attackers.

Given the strong cyber-physical interactions in today's smart grid, false data injection (FDI) attack can readily mislead the state estimation and influence the system operation by manipulating meter measurements. In this paper, a new FDI attack strategy is considered where multiple attackers cooperatively launch an unobservable attack. Firstly, the entire transmission system is partitioned into several subsystems, with each attacker only acquiring and manipulating the measurements in its local area. With limited communications among neighboring attackers, all of them can successfully modify the estimated states without being detected. In addition, by taking practical constraints into account, a least-effort attack problem is formulated and subsequently solved by a distributed alternating direction method of multipliers (ADMM)-based approach. Several case studies implemented on a 4-bus and IEEE 118-bus power systems have finally demonstrated the effectiveness of the proposed approach in the scenario of multiple attackers.