State-of-the-art and future trends in soft magnetic materials characterization with focus on electric machine design – Part 2

Abstract

The first part of this two-part article is about a retrospective view of material characterization, starting with the work of J. Epstein around the year 1900 and respective basic explanations. Consequently, the work presented herein is about the current state-of-the-art, recent developments, and future trends in characterization of ferromagnetic materials. Modeling is in fact a type of characterization, in a phenomenological and mathematical sense, and therefore it is treated with due attention in this article. Quantifying the properties of soft magnetic materials retains significant scientific attention. Thanks to new optimization techniques and advances in numerical evaluation, modern electromagnetic devices feature high utilization. Classical models exhibit assumptions that do not allow modern machine or device characterization with high accuracy. In this manuscript, typically applied techniques and recent incremental improvements, as well as newly developed models are introduced and discussed. Moreover, the significant impact of manufacturing on the materials’ characteristics and its quantification is illustrated. Within this article, a broad overview of the state-of-the-art as well as recent advances and future trends in soft magnetic material characterization is presented. Thus, it is a valuable reading for beginners and experts, from academia and industry alike.

The Influence of Cutting Technology on Magnetic Properties of Non-Oriented Electrical Steel—Review State of the Art

“…When simulating the operation of an electric machine using FEM, considering the influence of the cutting effect on electromagnetic properties, three approaches are possible [116], shown in Figure 2.…”

“…When simulating the operation of an electric machine using FEM, considering influence of the cutting effect on electromagnetic properties, three approaches are poss [116], shown in Figure 2. The first is to apply to each area, e.g., a stator tooth, averaged parameters determined considering the width of a given element.…”

Iron Loss Calculation Methods for Numerical Analysis of 3D-Printed Rotating Machines: A Review

“…FEM-based solvers usually use a post-processing step to calculate iron losses. In this solving step, using the calculated magnetic flux distribution values, loss values are calculated for the element using an analytical material model [91][92][93]. The accuracy of these formulae usually depends on the measurements to which the free parameters of the formula are fit.…”

“…The accuracy of these formulae usually depends on the measurements to which the free parameters of the formula are fit. These measurements can be made on an Epstein frame, a toroidal core setup, or in a single-plate tester [91], depending on which method is best suited to the particular calculation. The following section aims to introduce these iron-loss-calculation methods and describe their applicability, besides their advantages and disadvantages.…”

A Methodology for Calculating the R-L Parameters of a Nonlinear Hysteretic Inductor Model in the Time Domain

“…A description of the behaviour of nonlinear electric circuits with magnetic cores employed in electric machines during steady-state and transient working regimes usually requires knowledge of the magnetic characteristics of the material used (magnetisation curve, i.e., the φ = φ(i) (magnetic flux vs. current) dependence, hysteresis loops, power losses, etc.) [1][2][3][4][5][6][7][8]. Such an electric circuit can alternatively be represented by: (1) an inductance L exhibiting a single-valued (SV, thus neglecting hysteresis) magnetisation curve connected in parallel to a resistance R [1], (2) a dynamic hysteretic core model [1] or (3) an electric network (such as a Cauer circuit [3,4]).…”