Thermal Stability of a DC/DC Converter with Inductor in Partial Saturation

Inductors operated in quasi saturation in DC/DC converters allow reduction of the core size and realization costs; on the other hand, they imply an increase of dissipated power that can jeopardize the thermal stability of the converter. In this paper, this issue is studied by a mathematical model able to represent both the inductor non-linearity and its temperature dependence. The main losses, such as ohmic, skin effect and magnetic, are taken into account in the model. The inductor is characterized by a polynomial curve whose parameters are a function of the temperature. Finally, the whole converter is modeled and simulation results, obtained on a boost converter, are compared with experimental measurements showing that the thermal behavior is reproduced in detail.