Method Study Of Power Grid Vulnerable Component Identification And Static Risk Assessment

The vulnerability of power system as the expansion of power grid’s security risks, hasbecome the heated study of the scholars at home and abroad. And it is a subject of profoundtheoretical value and practical significance to study how to conduct a comprehensive andreasonable assessment of the grid structure, so that we can find the weak link and takereasonable measures to enhance the grid’s ability.As for the study of the vulnerability of grid, it is right to take its inherent networkstructure and real-time running state into consideration. Therefore, the study of this thesis wasestablished from this two aspects. First of all, based on the random walk theory and the theoryof power flow tracing, we used the betweenness of power flow tracing and random walk toidentify the weak nodes and lines existed in the grid. Secondly, according to thecharacteristics of the closed element type and exposure element, we revised the calculationformula of the failure rate. And we used utility theory to assess the severity of faultconsequences by simulating the fault of fragile source element respectively. Based on theseand the risk theory, we started from the evaluation of the single index of element’s static risk,and then discussed the characteristics of subjective weight calculation by using analytichierarchy process and subjective weight calculation by using entropy weight method. Wecombined the two to study determination method on static risk index of comprehensiveweight, and then accordingly established static electric elements risk index calculation modelof comprehensive weight, and gave the calculation method of its static comprehensive risk.This thesis also based on the analysis of the actual case of IEEE14and IEEE39node systemto confirm the feasibility and effectiveness of the proposed method.