Study Of Automatic Contingency Selection Based On Fuzzy Theory

For the fast increase in the scale of the modern power grid, the traditional method with full AC flow calculates the contingency and estimates the security of the system, the result is accurate, but it is complicated and time-consuming, automatic contingency selection becomes very important to the contingency analysis.Focused on the limit of the conventional method, this paper presents a contingency ranking algorithm based on the fuzzy theory to minimize the masking effect. Considering the variation of the line outage the system power flow and the defined performance index, fuzzy inference system is constituted for the real power of the branch and the voltage-reactive of the bus exceeding the extreme. With the output of the model, we can rank for the contingency severity. Comparing with the traditional algorithm, the ranking results proved the method is effectiveness and feasible by IEEE-30 bus and a real power system.