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This paper compares two different identification methods of a static rate-independent energy-based hysteresis model with regard to the dynamic hysteresis loop shape prediction when coupled to the parametric magnetodynamic lamination model. The values of hysteresis model parameters are determined solely based on the quasi-static major loop. A semiphysical approach identifying the reversible and irreversible field components independently and a purely mathematical scheme using a differential evolution optimization algorithm determining all parameters simultaneously are compared. Both variants of parameter identification are analyzed in terms of hysteresis loop shape prediction for quasi-static as well as dynamic loops. [ABSTRACT FROM AUTHOR]

This paper discusses the implementation of the inverse Jiles–Atherton vector hysteresis model with the 2-D Finite Element Method (FEM) for the analysis of an induction machine operating as self-excited generator. A differential reluctivity tensor couples the hysteresis model with the magnetic vector potential-based finite-element model. Experimental and simulated results (transient and steady state) are presented. [ABSTRACT FROM AUTHOR]

Some soft magnetic materials are strongly dependent on the temperature, because of their low Curie temperature. In order to predict their behavior in electrical devices, engineers need hysteresis models able to consider the temperature. This paper is an attempt to consider the temperature in an existing model of static hysteresis through its parameters. Variations of some parameters with temperature are issued or build thanks to the literature. At the end, all needed parameters have an analytical law versus temperature. The simulation results are compared with measurements and discussed. [ABSTRACT FROM AUTHOR]

This paper describes a mathematical model for the dynamic magnetic power losses in the laminated steel stator of high-frequency permanent magnet machines, such as brushless dc (BLDC) motors. The model presented is based on a utilization of the dynamic Jiles–Atherton model. Accurate dynamic $B$ – $H$ curve fitting and magnetic power loss derivations have been achieved, where the calculated magnetic losses have shown $\sim 95$ % accuracy from 5 to 2000 Hz over a flux density range of 1.0–1.6 T. This approach has been applied to estimate the magnetic power loss of a small scale high-frequency (>10 000 r/min) BLDC motor, with calculated and measured losses being in close agreement. [ABSTRACT FROM AUTHOR]

This paper presents a vector hysteresis model based on micromagnetic theory. In this model, a magnetization state of a magnetic material is described by a collection of single-domain particles, and magnetic reversal processes due to domain-wall motions are treated approximately as a magnetization flip. The present model is applied to calculation of hysteresis properties of grain-oriented silicon steel. The simulation results show that the anisotropic hysteresis properties and iron loss can be reproduced accurately by the present model. [ABSTRACT FROM AUTHOR]

This paper deals with the mathematical definition of a general vector hysteresis operator in 3-D, as an extension of previous papers where the theory has been limited to the 2-D case. Although the paper is mainly focused on magnetic hysteresis, the definitions and the results reported can be applied to any general physical phenomenon that exhibits hysteresis. We show here the main general properties of the general hysteresis operator in 3-D. [ABSTRACT FROM AUTHOR]

Hysteresis models can incorporate the effects of operating conditions (frequency, stress, and temperature) on iron losses incurred in ferromagnetic materials. Among such models, the Jiles–Atherton (JA) and Preisach models are the most popular and various modifications of these have been proposed in the literature to model the effect of frequency, stress, and temperature on iron losses. Both of these representations produce accurate results compared with the curve fitting models and can be directly implemented in finite element simulations. Unfortunately, it is very difficult to incorporate all these effects into a single iron loss model that is computationally efficient and can predict iron losses with reasonable accuracy for a given range of these parameters. In this paper, an effort has been made to establish a relationship between JA and Preisach models and an interpolation-based approach is presented to predict iron losses that utilizes the Preisach model on top of the JA model and incorporates all of the above factors. It is shown that iron loss can be predicted accurately for any value of frequency, stress, and temperature. [ABSTRACT FROM PUBLISHER]

This paper presents a new flux-mnemonic dual-magnet brushless machine which incorporates both the neodymium-iron-boron (NdFeB) and aluminum-nickel-cobalt (AlNiCo) permanent magnets (PMs) for hybrid excitation. By applying a temporary current pulse in a small magnetizing winding to online tune the magnetization of AlNiCo PMs, the proposed machine can provide flexible air-gap flux control, thus achieving high efficiency at different speeds and loads. By newly using a parallelogram to model the AlNiCo PM hysteresis loop and then incorporating into the finite element field equation, the performance of the proposed machine is analyzed. Finally, experimental results are given to verify the simulation, confirming the validity of the proposed machine and its analysis. [ABSTRACT FROM AUTHOR]

We consider the quasi-static magnetic hysteresis model based on a dry-friction-like representation of magnetization. The model has a consistent energy interpretation, is intrinsically vectorial, and ensures a direct calculation of the stored and dissipated energies at any moment in time, and hence not only on the completion of a closed hysteresis loop. We discuss the variational formulation of this model and derive an efficient numerical scheme, avoiding the usually employed approximation, which can be inaccurate in the vectorial case. The parameters of this model for a nonoriented steel are identified using a set of first-order reversal curves. Finally, the model is incorporated as a local constitutive relation into a 2-D finite-element simulation accounting for both the magnetic hysteresis and the eddy current. [ABSTRACT FROM PUBLISHER]

To describe the vector magnetic hysteresis phenomenon of electrical steel sheets, an improved vector Jiles-Atherton hysteresis model is presented. The proposed model is developed based on Berqvist model. First, the anhysteretic magnetization function is improved by modifying the model parameters according to the excitation direction. By this, the modeling results are accurate under different alternating and nonsaturated rotating excitations. Furthermore, to model the magnetic property under saturated rotating excitations accurately, the proposed model is extended by modifying the model parameters according to the measured data. The proposed model is validated through comparisons between modeling and measured results under different alternating and rotating excitations. [ABSTRACT FROM AUTHOR]

Recent research results demonstrate that demagnetizing factors for various geometries can be precisely determined by employing 3-D electromagnetic field simulation. Using a technique developed by the authors, the demagnetizing factor resulting from the simulations match very well with experimental results for several series of samples with various geometries. The simulation technique developed by this project was also used for a spherical magnet using various field conditions, which has further proved the accuracy of this technique, whose results agree precisely with the theoretical analyses and mathematical calculation. Such simulation provides advantages over other methods including mathematical calculation and experimental measurement. Since any geometry with any dimensions can be simulated using the electromagnetic field simulation, the simulated results of “N” values can be stored in a data bank for any application using open-circuit measurements in the future. [ABSTRACT FROM AUTHOR]

A new hysteresis model is developed to describe clockwise hysteresis, in which the positive saturation is achieved for positive values of the input. The model is based on the traditional (counter-clockwise) Jiles-Atherton (JA) model and describes the input-output relation in the form of a first-order differential equation. The most important characteristics such as initial susceptibility, coercive fields, remanence, thermal stability, first and higher order reversal curves are discussed. A comparison with other two clockwise hysteresis models of hysteresis (i.e., the Preisach and Bouc–Wen models) is provided. It is proven that the clockwise JA model can describe novel hysteretic behavior that cannot be reproduced by the previous two models. The novel model is also appealing due its relatively simple numerical implementation and its small number of parameters. [ABSTRACT FROM AUTHOR]