Improved inductance calculation in variable power inductors by adjustment of the reluctance model through magnetic path analysis

This paper presents a study to improve the inductance calculation of magnetic elements for power converters, particularly important in the case of applications using variable inductors. Several factors have been taken into consideration, such as: the permeability definition under saturation, the temperature effect on the magnetic material behavior, and the distribution of saturated regions in the magnetic core which results in an accurate estimation of reluctance paths. Further depth is given to the study by using Finite Element Analysis to simulate a variable inductor and analyze the effect of the latter mentioned factors. The studied analysis is then compared with experimental results to prove the validity of the proposed improvements.