Analysis of transformer short circuit characteristics based on 3-D Finite Element Method

Based on a 3-D Finite Element Model built up in FLUX 3-D, this paper shows simulation results of a single phase transformer to study the behavior of its reactance during short circuits with respect to saturation effects. In the first step measurements on a real transformer were done to determine its equivalent circuit parameters and to verify the Finite Element Model. In the second step the influence of core saturation on the impedance was studied. From the result of this study it can be concluded that the saturation has a big impact on the maximum short circuit current and has to be taken into account for detailed network studies.