Fast search for transmission section based on power component of line

This paper proposes an algorithm fast searching for key transmission section based on power component of line. Firstly, graph theory is used to calculate the real power transfer among individual generators and loads, then classify the lines based on the Ward´s cluster analysis method to search the set of lines which have the similar power component to overload line, finally determine the parallel transmission section of the line according to the direction of the overload line and the set lines. As a result, the works of further calculation and security analysis can be reduced greatly. And fast security protection of key sections to prevent cascading tripping can be achieved accordingly. At last, the validity of proposed algorithm is verified by the calculation result of IEEE 14 test system.