The Research Of Security Risk Assessment For Power Transmission Grid Based On Cloud Theory

After20years of development, security risk assessment has been widely applied in the field of power transmission grid. Through the security risk assessment about power transmission grid, the electric power enterprise can know well its security risk status, clear the weak link in the grid, draw up relevant corrective measures, and improve the security operation level. However, with the development of the power transmission grid, the progress of science and technology and the growth of disaster enviromnet, new demands on the power transmission grid security risk assessment have been put forward. In recent years, all kinds of personal accidets,equipment accidents and network incident in operation of power transmission grid require that the security risk assessment should be further broaden and deepen on the basis of the traditional security risk assessment.Most of equipment in power transmission grid are exposed to the outdoor natural environment. A lot of work is done by person from the operation of the equipment, who is the most active and uncertain factors in the operation of the power transmission grid. All of these require the establishment of a security risk evaluation based on the concept of risk management with the risk identification, risk analysis,risk assessment, risk control in the risk management to realize equipment,penson and environment risk in control.Cloud theory, based on traditional fuzzy set theory and probability theory, accounts for the fuzziness and randomness and provides a powerful method for qualitative and quantitative integrated information processing. The thesis introduces cloud barycenter evaluation menthod to safety assessment of power transmission grid, and renders the reasonable conversion from qualitative concepts to quantitative descriptions.The thesis has established the power transmission grid security risk assessment index system from two aspects of person and environment based on the traditional safety evaluation. According to the established index system, questionnaire survey has been maked and index weight questionnaire survey has been issued. At the same time, person factors and environment factors questionnaire survey have been issued to the operating staff of a regional power transmission grid. Finally, the questionnaire survey results have been analyzed by cloud theory to determine the security risk status quo of the region’s power transmission grid.