Online synchronous generator out-of-step prediction by electrical power curve fitting

Abstract

In this study, by using generator electrical output power and rotor speed, a new algorithm for out-of-step prediction isproposed. In this online method, after fault clearance, the trend of generator output power will be predicted using sinusoidalvariable frequency function curve fitting. Finally, time-domain equal area criterion (TDEAC) is used to evaluate the transientstability. The mathematical proofing of TDEAC and its validity in large-scale systems are presented too. Real-time prediction,fast calculation, using only local parameters and estimation of the remaining time until instability are some of the proposedmethod's advantages. The performance of this algorithm is examined on IEEE 39-bus New England and Iran electrical powernetwork systems. The results show that the proposed method represents a valuable alternative for out-of-step protectionpossessing fast and high-efficiency performance. The simulations are carried out using the Power Factory® software and theproposed algorithm has been developed in MATLAB.