Investigation on the Occurrence of Ferroresonance with the Variation of Degree of Transformer Core Saturation

Abstract

AbstractFerroresonance is a complex behavior of an electric network which if sustained, may be dangerous for power system equipment. Besides establishing mitigation techniques, researchers are also working on the prediction of ferroresonance occurrence in susceptible networks. The study requires appropriate mathematical model of transformer for computer simulations. A geometrical approach had been proposed by Rudenburg in the year 1950. But it was difficult to prove those proposals experimentally as ferroresonance may lead to complete destruction of the transformer and other equipment under test. Objective of this paper is to study on ferroresonance and observe the effect of variation of degree of saturation of transformer core materials on ferroresonance. For that, the transformer is approximated with its nonlinear dynamic model. With the help of that model, a Simulink block diagram has been developed in MATLAB. The Simulink model is examined under various circuit conditions, and a conclusion has been drawn that higher degree of saturation of the transformer core material increases the risk of ferroresonance to occur in the network.KeywordsFerroresonanceNonlinear model of transformerHysteresis modelDegree of saturationMagnetizing curve