Dynamic Risk Assessment On Cascading Failure Of The Power Grid

With the continuous expansion of electric power industry scale and theimprovement of electric network technology, the electric network scale is continuallyexpanding. Electricity power grid interconnection improves the stability of the system,but the local fault may also make more important influence.In the past ten years, there were dozens of major power blackouts in theworldwide, many regional system "collapse" emerge in our country, through theanalysis of accident development process, it is not difficult to see that cascadingfailure is a direct reason of the loss of network stability, and effectiveness ofelectricity grid fault conditions affects the ultimate consequences. In this paper, thetheory and model of electricity power system cascading failure risk assessment aresummarized, which explains the defects existing in the prior art; After collecting theblackouts, the development process of the accident are analyzed by using ETAanalysis method, and with the use of CCA method,it analyzes the process ofcascading failures in dynamic propagation and key problems, in this way the cause ofthe accident and accident in different stages of the consequences are specified, whichis verified by the actual accident.Base on the analysis of the cascading failures transmit, the effects of the electricline stability, relay protection and electricity power adjustment, which are dynamicfactors of the accident transmission, on fault transmit is analyzed. According toelectricity power grid dynamic adjustment process, the index of risk probability andseverity of the cascading failure are reached, it helps to formulate the dynamic riskassessment process and risk calculation model. Finally, the electricity power systemsimulation software are used, taking5machine13bus test system for example, toverify the dynamic risk assessment theory prove its effectiveness.