Considering 2D Magnetic Fields and Air Gap Geometry in the Estimation of AC Losses in Round Wire Windings

The use of classical formulations based the assumption of unidirectional magnetic fields for the estimation of alternating current (AC) losses in windings neglect some critical physical aspects observed in real components. This leads to higher estimation errors for higher frequencies, which are ever more important in modern power electronics. Even though newer methods appeared, the level of accuracy of analytical methods can be further improved. This work proposes a new approach for round wire windings, considering both cited factors, i.e., 2D magnetic fields and air gap geometry. The results are compared with previous works and finite elements simulation results. Although this work describes the method with only one coil, the same approach can be applied to two or more coils, including transformers with air gaps.