Identification of Key Nodes of Targeted Attack in Urban Power Grid Based on Asymmetric Grid Structure Information

Accuracy of key node identification results is affected by the asymmetry of power grid structure information between attackers and defenders. Therefore, this paper proposes a key node identification method based on asymmetric network frame information for targeted attack of urban power grid. First, based on the perspective of attackers, a dual-objective optimization model of urban power grid topological completion is established considering the observable signal information of urban power transmission cables and the rationality of completion grid structure. Furthermore, considering the asymmetry of the information of the attack and defense network, a two-layer optimization model is established to identify the key nodes of the system. Giving that the real existence of the restored cable will lead to the uncertainty of node failure, and the attacker has the preference to pursue the deterministic impact consequences, the grey system theory is used to convert the damage consequences of the nodes connected with the restored lines, so as to reduce the damage probability of such nodes. In the last part, the KKT (Karush-Kuhn-Tucker) condition is used to transform the two-layer problem into a single-layer single-layer mixed integer linear programming(S-MILP) model. Simulation results verify the effectiveness of the proposed method, and the proposed method can obtain a high accuracy completion grid. At the same time, compared with the scenario with symmetric grid information, the identification results of the key nodes in the asymmetric scenario take into account the severity and certainty of the consequences of node failure, which reflects the actual psychology of the attacker to maximize the certainty revenue and makes the results more reasonable. ©2023 Chin.Soc.for Elec.Eng.