Finite Element Analysis Model for Failure Analysis of Epoxy-Bonded Continuously Transposed Cable

Power transformer windings usually are made from continuously transposed cable (CTC) in order to reduce eddy current losses and reach low winding cost. The main disadvantage of this kind of multiple stranded conductor is the low bending stiffness due to the slender strip cross section. In the worst case winding deformations can occur, if the transformer is exposed to high short-circuit currents. An increase in bending stiffness can be realized with epoxy-bonded CTCs: The strips are covered with an epoxy resin that melts during the factory drying process of the windings' insulation and glues the strips together. In this paper a mechanical Finite Element Analysis (FEA) based simulation model for such kind of CTCs is proposed. The aim is to investigate the increase in buckling strength…