Vulnerable Point Identification Using Heterogeneous Interdependent Node Theory for Distribution Systems

In order to reduce the occurrence or expansion of accidents and maintain safety in distribution networks, it is essential to find out the vulnerable points for the power system in time. In this paper, a vulnerable point identification method based on heterogeneous interdependent (HI) node theory and risk theory is proposed. Compared with the methods based on betweenness theory, the method based on HI nodes theory can deal with the shortcomings of the power flow shortest path, and consider the direct and indirect relationship of nodes. It is more suitable for identifying vulnerable points in a realistic power system. First, according to the analysis of heterogenous interdependent networks, the HI nodes are defined and used to evaluate the utility coupling value of each node. Then an identification indicator, which combines the utility coupling value and the risk indicators, is utilized to evaluate the vulnerability of each node. Results show that the proposed method is a suitable one to find the vulnerable points and better than betweenness-based methods for a distribution network.