A Graph-Based Model for Transmission Network Vulnerability Analysis

A novel cascading faults graph (CFG) is constructed using the cascading failure model based on the continuous temperature evolution process of line. The CFG contains the temporal-spatial characteristics of fault chains, which is able to facilitate the cascading failure analysis in network science and statistics perspectives. For characterizing the vulnerability of lines and transmission networks, indices based on the CFG are proposed, where the line vulnerability is presented as propagation vulnerability. The characteristics of the proposed CFG and the mechanisms of cascades are revealed based on the properties of multiorder topology. Through simulations based on standard test and real systems, the validity of the proposed CFG and indices are verified. The results show that the vulnerability distribution of lines is highly heterogeneous, and the vulnerability of lines appears assortative correlation, which indicates that successive failures between two lines with high vulnerability are easy to occur in high probability. The results also show two vulnerability characteristics of transmission networks, the constancy of the vulnerability correlation and the vulnerability mitigation. The proposed method greatly reduces the number of upgrades of lines and can effectively prevent cascading failures.