Identification Method of Vulnerable Lines in Power Grid Based on Comprehensive Sensitivity of Branches

Abstract

This paper proposes a method of vulnerable lines identification in power grid based on comprehensive sensitivity of branches in order to effectively prevent large-scale cascading faults. Firstly, this paper improves the power transmission distribution factor, and consideres the influence of load rate of the branch. The sensitivity index of the branch power flow is proposed to reflect the sensitivity of the branch to the power flow transfer. Then, this paper modify the branch breaking distribution factor, and the branch breaking sensitivity is constructed to reflect the branch breaking vulnerability from the two aspects. Entropy weight method is used to allocate the weights of the two indexes to screen out the vulnerable lines in the system.The identification results are compared with related documents, and finally simulates by the IEEE39 system This paper uses three attack methods to attack, and the network transmission efficiency is used to reflect the changes of the attack method to the system. The results prove the feasibility and rationality of the method.