Research On Risk Assessment Method Of Cascading Failure

Many large blackouts of electric power system in the recent years are mainly manifested by cascading failure. In order to guarantee secure and reliable circulation of the electrical network in a higher level,it's of great importance to strengthen the forecast of cascading failure. But when forecast analysis,some uncertain factors such as Initial failure position and types that mightn't be given certainly beforehand,therefore it's necessary to introduce probability analysis method. According to physical process of cascading failure and combining to probability features of each stage event,the authors propose a probability analysis approach of cascading failure. We carry on the detailed probability description of each link of cascading failure according to cascading failure possible development succession process,and simulate the process of cascading failure. In order to find the weakness of power system,the risk of power system is assessed by voltage excess risk,load isolated risk and so on. By means of these theories,the software for simulation and assessment of the risk for power system cascading failure is developed. The results of applying the proposed method to IEEE 39-bus test system further show the rationality of this method. The authors propose method to assess important of the beginning fault line,then have carried on the analysis and confirmation with the low-power sample.