Ice Disaster Risk Evaluation Of Power System Considering Multi-Factors

High quality and reliable supply of electricity is required in modern society. In recentyears, however, the frequent extreme weather events bring great threat to secure and stableoperation of power system. Especially in the period of2008ice disaster, power facilities inmany part of southern China were seriously damaged; power supply had been severelydisrupted and the national economy suffered great losses. Thus the research on power systemreliability evaluation is of great engineering value and practical significance.In this thesis the background and the significance of ice disaster risk evaluation of powersystem are firstly presented. The necessity of studying is pointed out and then the researchstatus in ice disaster risk of power system at home and abroad are discussed, including growthmodels of ice, research on melting ice technology and so on.Risk assessment is a fertile subject, which ranged over a number of fields. Beforeintroducing ice disaster risk of power system, the method of acquisition original reliabilityparameters for power system is presented. It is the prerequisite and basis for reliabilityanalysis or ice disaster risk of power system. Under the condition of lacking of historystatistical data, the grey bootstrap method is adopted to regenerate a large number samplesand then the reliability parameters can be solved. However, new line even have no historystatistical data, in that case, the reliability parameters of new line can be calculated accordingto the lines with known reliability parameters, by using fuzzy clustering and similarity. Thenthe two basic methods of risk assessment (the analytical method and Monte-Carlo simulationmethod) are presented, the model of Fault analysis based on DC power flow and optimal loadshedding based on DC optimal power flow, including risk index are recommended. And thenunder the consideration of the damage details of power system in2008ice disaster and thesuccessful experience of fighting against the ice storm in early2011, the influencing factorsare deeply studied, including probability distribution of year’s ice extreme value, the grid’sdesigned ice thickness, the use of de-icing machine and the rate of resource guarantee.Finally ice disaster risk of a simple test system and an actual power system are simulated,the results demonstrate the effectiveness of the proposed method. And then the sensitivity ofseveral key factors to the risk is analyzed, such as the use of de-icing machine and the rate of resource guarantee. As for reducing ice disaster risk of power system, the result can alsoprovide power department beneficial reference and advice.