Research Of Vulnerable Lines Identification In Power Grid Based On Grid Structure And Running State

In recent years,a spate of blackouts occurred around the world.A small number of vulnerable lines contributed to the severity in the development of the accident.So find out the few key vulnerable lines played a key role to prevent the occurrences of cascading failure.The existing assessment methods for line vulnerability in power system suffer the drawback that it is difficult to present a full view.Therefore,we propose a more comprehensive assessment method of vulnerability of lines,the main contents are as follows:This paper begins with the angle of the grid topology view,based on complex network theory and Kirchhoff laws,put forward the index of electrical betweenness,and make the example analysis,get the keyvulnerable lines that only based on grid structure.Then consider the running state of the power grid,put forward three indexes:power factor,load rate offset and node voltage offset to indicate the fragility of the system.In this paper,we get the value of each index based on PowerWorld Simulator,in view of the analytic hierarchy process to determine the weight of indicators,and make the example analysis,get the keyvulnerable lines that only based on running stateFinally,integrated grid structure and operating state,to form a comprehensive evaluation system.Based on entropy weight method to determine the weight of each index,and construct the evaluation model of vulnerable lines.Taking IEEE39 bus system as the testing example.The validity and superiority of the method are proved by comparing with the results of other methods.