Nonlinear Power Inductors for Large Current Crest Factors

Abstract

A practical method is presented: how to adjust the inductance curve of a nonlinear (saturable) inductor with respect to a desired shape. For this purpose, a nonlinear model was developed based on finite element method (FEM). It is shown how a highly efficient construction with low stray fields and maximum package density can be achieved. Different prototype inductors were realized to illustrate the practical capability of photovoltaic (PV) inverters as well as active power factor correction (PFC) applications. All simulations are verified by means of experimental data drawn from electrical measurements.

Determination of the roll-off value in the air-gapped inductor of a DC-DC boost converter circuit with FEA parametric simulations

“…The green zones in the graph can be defined as acceptable roll-off values (60%) for the desired inductance value. Thus, the parametric inductance values have been determined with the 3D electromagnetic modeling and more realistic conditions [26]. The flux linkage graph, which is defined as winding flux in inductors, shows the electromagnetic behavior of the airgap designed core.…”

Non-linear inductor modelling for a DC/DC Buck converter

“…Anyway, this jeopardizes the power density since during operation the inductor's capabilities are not fully exploited [7,8]. Recently the use of inductors working in partial saturation has been considered in literature where it has been assessed that the advantages in using a more compact inductor imply an acceptable amount of losses [9][10][11]. From the theoretical point of view, if the hypothesis of linearity for the inductor is removed, the value of the inductor varies with the current.…”