Calculation of iron losses in ferrite toroids using FEM and complex vectors

In this paper the FEM based approach is used to analyse the electromagnetic field distribution in a ferrimagnetic core with rectangular cross section. This numerical method provides a way to accurately visualise the field distribution. The iron losses which consist of magnetic loss, dielectric loss and eddy current loss are calculated separately based upon the electromagnetic field distribution. From these calculated results, it is found that at low frequency the magnetic loss is the major contributor to the total losses, but when frequency reaches the MHz range the dielectric loss becomes significant and can´t be neglected. The calculated results are also compared with measured results and good agreement between the two values is achieved