Research On Contingency Administration Of Real-time Stability Evaluation For The Operating Condition Of Electric Network

Today the voltage grade of electric network, the configuration of the power system and the network interconnection is becoming more and more complicated, so administers and experts have paid much attention on the stability of electric network, and advances the new requests on stability evaluation. The conventional programming stability evaluation method belong to off-line analysis, it needs much time and the model is coarse, the content it researches is comparatively immovable, so there are many localizations to reflect the stability level of the current operating mode. Therefore, the research on real-time stability evaluation for the operating condition of electric network is helpful to detect the risk of operating mode and advance amelioration or prevention measure, it is significant to improve the security and economy of the production, operation and dispatch of electric network. Contingency screening and ranking is the most important research content in stability evaluation. It is a focus experts and doctors is researching on that how we can quickly selection the contingencies that is intimidating the system operating condition or can make the system critical instability. This paper is based on a project of Fujian Electric Power Limited Company: Power System On-line Dynamic Evaluation and Assistant Decision-making System. The contingency administration and precept of the on-line stability evaluation has been studied and designed. The arithmetic flows of contingency automatic creation and contingency screening and ranking have been designed; Using the decision tree method of data mining, the features of failures which affect the system stability level primarily have been extracted respectively. The contingency screening and ranking has been realized by on-ling matching features of failures and history evaluation database; Considering the eight operating modes of Fujian, the stability level of Fujian power system under some failures reflects to power flow change of some transmitting lines by using decision tree method to extract features of some failures of Fujian system. The extracted features not only can provide method to contingency screening and ranking but also reduce the scope that dispatchers want to supervise some failures. In order to assure that the extracted features can reflect factually the power network practical operating condition ,using features extraction to contingency screen and rank need detailedly consider mathematics model of the system, network configuration change, the dispatching policy, restriction of power system, the operating mode of units, maintenance plan of lines, real-time change of loads, etc. So there are much work to be carried out in this field in the future.