Study On Vulnerability Assessment Of Important Infrastructure About Power Grid In Shanghai

With the rapid development of social economy, electric power system gradually developed into a very large scale complex system which consist of the power grid, extra high voltage and large unit.The large-scale interconnection of power grid has realized the optimal allocation of resources in a wider range, but it also reduced the security and stability of power grid operation, which caused the frequent occurrence of all kinds of power grid accidents, and brought significant social impact and economic losses. In this paper, we take the important infrastructure of power grid as the research object. On the basis of analyzing the mechanism of the sudden events of all kinds of power grid, this paper mainly analyzes the constitution of the physical vulnerability, constructs the vulnerability assessment system, studies the scientific and effective evaluation methods, and provides scientific basis for the effective measures to reduce the vulnerability of the important infrastructure of the power grid.Firstly, based on the study of the definition and connotation of the critical infrastructure vulnerability, the mechanism of the emergency event of the grid is analyzed, in order to define the structure and influencing factors of the vulnerability of the grid. In this paper, we take converter station, hub substation and high voltage transmission lines (including the tower) as the basic unit of vulnerability assessment, construct PSR vulnerability assessment model based on pressure (P), state (S) and response (R).Based on the three dimensions of PSR model, the vulnerability assessment index is extracted, and the rough set method is used to reduce the vulnerability assessment index system. Referring to the mature risk assessment and vulnerability assessment methods in other fields, we study the calculation method of the critical infrastructure vulnerability index and the grading criteria.Secondly, based on PSR vulnerability assessment model, the vulnerability assessment and classification of the evaluation units are carried out by using the triangulation method. The vulnerability of the 71 line segments contained in the "5109" section of the transmission line is calculated and analyzed by the example of Shanghai 500kV "Yang Xing-Yang Gao" transmission line, which provided the scientific basis for the further improvement measures; Using DEA (the data envelopment analysis) method, taking nine of 500kV substations such as 500 kV Sijing substation and 500 kV Huangdu substation as samples, the vulnerability index measure example verification is carried out. The validity of the model is verified and the corresponding conclusions are given.Finally, based on the research results of this paper and the requirement of the State Grid Corp’s vulnerability assessment management, the vulnerability assessment management system of the power grid infrastructure is developed on the "SoTower" system development platform of State Grid. The assessment management system is formed by the vulnerability assessment, data analysis, early warning management and basic information management, and other major functional modules. It will help all levels of power companies to carry out self-vulnerability assessment and expert assessment work, and analyze the acquisition of data according to established threshold for different levels of vulnerability risk early warning in order to find out the weak link in the operation of the power grid in time. We can take preventive measures to prevent the occurrence of power grid emergency in order to accomplish the overall level of network security management.