Cyber-physical system fusion modeling and robustness evaluation

Smart grid is a typical cyber-physical system. In order to effectively evaluate the robustness of the system after cascading failures, combined with complex network theory, a cyber-physical system fusion cascading failure model is proposed. The power system adopts the AC power flow probability model to simulate the cascading failure process of the power grid. The information network constructs the corresponding scale-free network, according to the complex network theory and selects the node with the largest degree as the informative network dispatch center. The coupling model is constructed with the topological centrality index, the optimal scheduling process adopts the AC optimal power flow strategy. The simulation analysis of IEEE39 node system shows that the information network update will weaken the robustness of the system during the cascading failure of the cyber-physical system, the robustness of each transmission line increases nonlinearly with the change of the grid tolerance coefficient, and there are critical thresholds to make the robustness no longer enhanced. The enhancement of the coupling probability between networks also has a huge impact on the identification of vulnerable lines and robustness analysis of cyber-physical systems.