Conference Agenda

Predicting core loss and dynamic magnetization of soft magnetic materials for arbitrary excitations is crucial under high harmonic content. Dynamic losses for non-sinusoidal excitation evaluated using the Lavers formula and inverse Jiles-Atherton (JA) model are compared. The modeling of hysteresis curves with minor loops using the JA model is achieved by predicting three magnetic field strength components based on the field separation approach. Flux variation due to minor loops is considered by tracking the magnetic flux density in time using eddy current and excess field terms. The dynamic extension of the JA model to represent asymmetrical minor loops using the field separation approach is presented. The proposed method seems promising for use in finite element method (FEM) simulations for predicting iron losses in electromagnetic design problems involving power electronic converters.

The properties of electro-mechanical systems are intimately linked to the plastic deformation induced during the processing stages. This work presents a simplified multiscale modeling tool for anhysteretic magneto-mechanical behavior. The approach incorporates the effects of plasticity, from low levels of plastic strain up to necking. The model satisfactorily compares to experimental measurements, including the case of plastified samples subjected to reloading elastic stress. The very low computation cost of the modeling approach makes it suitable for the numerical study of magnetic devices under various mechanical states.

In this paper, a magneto-elastic coupling model for Grain-oriented (GO) silicon steel is established from the perspective of magnetic domain energy and crystal orientation. By analyzing the magnetization characteristics of grains at different directions under stress, it can be found that the magnetization characteristics of grains at different directions have different sensitivities and changing trends to stress. Therewith the magnetization characteristics of GO silicon steel sheets with strong Gaussian texture cut along different angles to the rolling direction are tested, and the reasons for the complex changes (non-linear, non-monotonic) of magnetization characteristics of silicon steel sheet under stress are analyzed.

This paper proposes to highlight the electrical phenomena around the interface between the plies of a stratified composite material. A predictive homogenization method based on the generation of virtual materials taking into account inter-ply phenomena in order to calculate the conductivity tensor for different ply sequences is presented.

Controlled Curie point materials are considered as innovative materials due to their property of abrupt magnetic extinction when their temperature exceeds a specific threshold. A coupled electromagnetic and thermal FEM model for induction heating of a magnetic material with a low Curie point temperature is presented.

The simulation results allow a comparison of the induced power density for different temperatures.

Play models that account for hysteresis phenomena are widely used to analyze magnetic fields with high accuracy. The accuracy of the model depends on the number of symmetric measured hysteresis loops. However, as the number of loops increases, the time required for measurement increases. In this paper, we show that machine learning can interpolate unmeasured loops from a small number of symmetric loops. We also demonstrate the effectiveness of the method by applying it to a simple model with a small minor loop applied.

This paper presents an approach for determining the two-dimensional electrical conductivity mapping of an anisotropic carbon fiber reinforced composite ply. The approach consists to subdivide the CFRCM UD ply into several zones of identical dimensions (1, 4², 4n zones, with n>2) and measuring the DC resistance between two electrodes placed at the ends of the bordering zones, following a clearly defined measurement plan presenting the different positions of the electrodes. On the other hand, the subdivided CFRCM UD ply is modeled by a two-dimensional electrostatic formulation (electrical conduction problem) and solved using the finite element method implemented in MATLAB. The solved model is used to compute the resistance for each electrode placement position. The inverse problem technique is then applied to find the transverse and longitudinal conductivities of all zones of the subdivided CFRCM UD ply. The proposed approach is, first validated on an anisotropic conductive material with kwon electrical conductivities, and then applied to the CFRCM UD ply.

AC magnetic property of core material in a high-frequency range is represented by the combination of the play model and the Cauer circuit. The resistors and the hysteretic properties of inductors in the circuit are determined from measured BH loops at two frequencies. For the convenience of parameter identification, several analytical solutions of the eddy-current field are introduced and compared. The iron loss at 10 kHz-300 kHz is calculated by using the four-stage Cauer circuit. The loss is accurately represented for the sub-MHz range by the proposed model.

In this paper, an implementation of hysteresis in a multiscale model for ferroelectric materials is presented. Hysteresis is introduced directly in the energy formulation, allowing the model to capture both electrically-induced or stress-induced hysteresis. The results predicted by the model for different electro-mechanical loadings are compared to experimental data in the literature, and show a good quantitative and qualitative agreement.

To accurately calculate the iron loss for the high-speed permanent magnet motor under PWM control, it is necessary to account for the excess loss. We investigate the modeling of excess loss in the presence of DC magnetic flux superposition. The proposed model is used as a post-process of the electromagnetic finite element analysis. In this paper, we describe the primary investigation for this modeling which was shown to represent well the excess loss in a limited frequency range. Furthermore, we highlighted that reliable measurements of the symmetric B-H loop and the iron loss under DC magnetic flux superposition are necessary for the excess loss modeling.

The direct comparison between analytical studies and micromagnetic simulations for stable magnetic skyrmion phases has been systematically investigated. The magnetic skyrmion state on a perpendicularly magnetized thin film exists when the magnetic domain wall energy, which competes with the perpendicular magnetic anisotropy energy, the exchange stiffness energy, and the interfacial Dzyaloshinskii-Moriya interaction energy, becomes negative. In this study, we demonstrate analytical formulas to provide numerous convenient estimations of the stable magnetic skyrmion phases with various magnetic parameters. Consequently, the analytical formulas for the magnetic skyrmion phases as a function of ferromagnetic layer thickness are successfully built. To verify our analytical model, a GPU-accelerated micromagnetic simulations are performed. Both analytical formulas and micromagnetic modeling are in good agreement with each other.

Hysteresis model of soft magnetic material enables an accurate estimation of the losses in electrical application. Their accuracy and reliability in simulation software represents a key for designing and monitoring these applications. In a single crystal, the domain walls are pinned to the defects and impurities. The resulting Barkhausen jumps induces local eddy current and heating in the material. In this article, a vector Jiles-Atherton model is developed based on the analysis of these phenomena.