Finite element modeling of saturation and eddy current effects in commercial variable transformers

This paper presents the methodologies and some of the results of performanc e modeling of variable transformers. This is done by finite element (FE) mo deling and computation of 3D magnetic Held distribution in commercial varia ble transformers used as voltage stabilizers. The results are presented in terms of the effects of core saturation and eddy currents in the top plate on magnetic field distribution in and around the transformer core. It is sh own that the magnitude and distribution of this field is affected by operat ional regimes characterized by brush and tap positions which determine the current distribution in the winding.