Identification of key transmission section based on geographic partition optimization and graph theory

The key transmission section is a reflection of power system weaknesses and is the focus of monitoring by grid operators. To quickly and efficiently obtain the key transmission section of the grid, this paper proposes a quick-searching method for the identification of the key transmission section. First, the existing geographic partition of the grid is optimized by the end node shrinkage and regional links optimization. Then, the adjacency matrix and path matrix of the optimized grid partition are obtained based on the principles of graph theory, and the transmission sections of the grid are found through the simple calculation of these matrices. An improved power flow betweenness index is designed using the power flow betweenness and line transmission capacity margin which is used as the identification indicator to identify the key transmission section within the found transmission sections. Finally, the case studies are conducted which demonstrate the practicality and validity of the proposed key transmission section identification method.