Approximately Optimal Cyber-Routing Attack Against Distributed Fusion Estimation With Energy-Harvesting Constraint

With the expansion and networking of power systems, distributed fusion estimation (DFE) has become integral to state monitoring. However, emerging cyber attacks, especially on data transmissions of wireless sensors, present significant risks to power system security. To evaluate attack impacts and strengthen defense resilience, this article investigates the security vulnerabilities in DFE of power systems, focusing on cyber-routing (CR) attacks with energy harvesting constraints. The CR attacker may corrupt some sensor measurements transmitted over wireless networks to local estimators, indirectly compromising the fusion estimate when aggregating the corrupted data. Aiming at maximizing the fusion estimation error covariance, a joint optimization problem is first established to comprehensively analyze the attack strategy, including target selection and action solving. To facilitate the execution of attacks, this issue is reformulated into a solvable suboptimization task utilizing the upper bound approximation technique. The optimal attack actions of compromised sensors and the attacking target set with a threshold-like structure are obtained via a two-stage solution approach. Additionally, an algorithm for generating attack targets is developed, applicable to both constant and time-varying energy harvesting conditions. Finally, all theoretical results have been illustrated by IEEE 39-bus power system.