3D non-linear magneto-thermal behavior on transformer covers

In real 3D metallic structures excited by electromagnetic fields some areas are strongly saturated while others not. In particular, this performance has to be taken into account when analyzing the 3D magneto-thermal behavior on transformer covers. To have a deep understanding of these complex phenomena the influence of the material non-linear magnetic characteristic is explained in detail based on a non-linear penetration depth electromagnetic analytical model. Concerning the thermal analysis, it is crucial to accurately set the subsequent thickness of the heat source volume regions from the concept of the magnetic field non-linear penetration depth, which is the novelty introduced in this paper. The temperature distribution is computed with the Finite Element (FE) Method (FEM) on metallic cover plates heated by electromagnetic induction and results are compared with measurements for the validation of the presented model.