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Hysteresis characteristics of the general spin-S S > 1 ) Heisenberg model have been studied within the effective field approximation. Particular emphasis has been paid on the large negative valued crystal field region. Since spin-S Ising model displays maximum number of 2 S windowed hysteresis loops in this region, this investigation gives the answer of the question: what is the effect of the anisotropy in the exchange interaction on this multiple hysteresis behavior? As an answer, rising number of windows in the hysteresis loops have been observed.

The objective of the present paper is to generalize the vector Preisach hysteresis model to take dynamic effects into account. A comprehensive analysis of the vector behavior has been performed by a single sheet tester with a specimen of round shape. The locus of the magnetic flux density vector has been controlled by a digital measurement set up at different frequency. An inverse vector Preisach hysteresis model has been built up by viscous-type scalar models and an identification procedure has been developed to follow the measured data. Finally, the model has been inserted into a finite element procedure through the fixed point technique to simulate electrical engineering problems.

This paper presents a simple dynamic vector-play model to calculate the iron loss and describe the vector hysteresis behavior of a non-oriented (NO) electrical steel sheet (ESS) under 50 Hz rotating magnetic fields. Based on the iron loss separation theory, the proposed model is separated to the static hysteresis component and eddy current component. The static hysteresis component is constructed by vector play model, which is identified by using 1 Hz minor $B$ – $H$ loops. And two coefficients $\omega _{x}$ and $\omega _{y}$ are introduced to consider the anisotropic property of NO ESS and the excess loss of eddy-current component under 50 Hz magnetic field. The validity of the proposed dynamic vector hysteresis model is verified by comparing it with the experimental results under various 50 Hz magnetic field conditions.

An anisotropic vector hysteresis model based on the improved isotropic vector play operator has been presented to predict the magnetization behavior of anisotropic hysteresis materials. The required parameters can be identified from the major hysteresis loops in all principal axes, which can be easily measured, or are directly available from magnetic material manufacturers. The presented model, which has been successfully implemented in 2-D and 3-D transient finite-element analysis, is validated by numerical experiments and measured data cited from TEAM problem 32, and is applied to simulate a synchronous reluctance motor with an axially laminated anisotropic rotor.

This paper presents an improved identification algorithm of the scalar play model, and suggests a novel vector play model to describe the vector hysteretic behavior of a nonoriented electrical steel sheet (ESS) under rotating magnetic fields. The proposed identification algorithm gives much better numerical accuracy than a conventional one by assigning more play operators than the measured asymmetric minor loops. The vector-shape function of the suggested vector play model consists of two scalar shape functions, which are independently identified by using measured hysteresis loops under alternating magnetic fields along rolling and transverse direction of ESS, respectively. The vector play model, furthermore, employs a nonlinear coefficient, which is a function of the magnitude and direction of magnetic flux density, to increase the numerical accuracy. The validity of the suggested vector play model is verified by comparing it with experimental results under various magnetic-field conditions.

In many transformer applications, it is necessary to have a core magnetization model that takes into account both magnetic and electrical effects. This becomes particularly important in three-phase ...

A computationally efficient and robust neural network-based model to reproduce the hysteresis phenomenon for soft ferromagnetic alloys is here presented, as well as a dedicated procedure to generate a suitable training set from a minimal set of experimental data. Firstly, an accurate experimental verification has been performed for a commercial NGO electrical steel, measuring a family of hysteresis loops under sinusoidal and non-sinusoidal magnetic induction waveforms. The Preisach model of hysteresis, identified with the sinusoidal loops, has been exploited to generate a wider data set, which consists of a family of first-order reversal curves (FORCs), suitable to train the neural network. Then, a neural network-based hysteresis model, with the capability to reproduce the eventual presence of sub-loops, has been developed. The two simulation approaches have been validated taking into account the other experimental data, which consist of a family of hysteresis loops measured under different types of magnetic induction waveforms. The comparison between the Preisach model and the neural network-based model also covers the simulation of the waveforms found in magnetic systems supplied by pulse-width modulated (PWM) signals. The substantial agreement found indicates that the neural network model can replicate the behaviour of the Preisach model with a considerable advantage in terms of computational cost and memory allocation. In addition, the possibility to be quickly inverted makes the proposed method suitable for matching with FEM solvers.

Preisach-based method was used to characterize a series of BaTiO3 hysteresis loops with varying external field frequencies. A stochastic adjustment of hysterons' weight was performed to obtain the Preisach densities. These densities, in representing the hysteresis responses, were characterized with three key parameters of the 3-dimensional hyperbolic-like distribution. One of the parameters relates directly to coercivity, while the other two concurrently represent polarization derivatives close to the coercivity, and emphasize an adaptability of the material to the external field around the main body of the loops. Thus, this approach can be extended to characterize other series of hysteresis loops to study changes of material responses influenced by varying external field frequency factor.

Dynamic magnetic hysteresis properties in a two-dimensional mixed Ising system designed with integer and half-integer spins, namely spin-1 and spin-5/2, are investigated comprehensively on the basis of the mean-field approximation and the Glauber-type stochastic dynamics, namely dynamic mean-field approximation (DMFA). In particular, we examine the effect of Hamiltonian parameters on dynamic hysteresis properties. As a result of this examination, some characteristic hysteresis behaviors are obtained, such as the existence of single, double and triple hysteresis. Moreover, we study to obtain coercive field and remanent magnetization. Our results are compared with some experimental and theoretical works to find a qualitatively good agreement.

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.

The Preisach function is considered as a product of two special one dimensional functions, which allows the closed form evaluation of the Everett integral. The deduced closed form expressions are included in Preisach models, in particular in the static model, moving model and a rate dependent hysteresis model, which can simulate the frequency dependence of the magnetization process. The details of the freely available implementations, which are available online are presented. The identification of the model parameters and the accuracy to describe the magnetization process are discussed and demonstrated by fitting measured data. Transient electric circuit simulation with hysteresis demonstrates the applicability of the developed models.

In this paper the hysteresis energy losses in two non-oriented industrial steels (M400-65A and M800-65A) were determined, by means of an efficient classical Preisach model, which is based on the Pescetti–Biorci method for the identification of the Preisach density. The excess and the total energy losses were also determined, using a statistical framework, based on magnetic object theory. The hysteresis energy losses, in a non-oriented steel alloy, depend on the peak magnetic polarization and they can be computed using a Preisach model, due to the fact that in these materials there is a direct link between the elementary rectangular loops and the discontinuous character of the magnetization process (Barkhausen jumps). To determine the Preisach density it was necessary to measure the normal magnetization curve and the saturation hysteresis cycle. A system of equations was deduced and the Preisach density was calculated for a magnetic polarization of 1.5 T; then the hysteresis cycle was reconstructed. Using the same pattern for the Preisach distribution, it was computed the hysteresis cycle for 1 T. The classical losses were calculated using a well known formula and the excess energy losses were determined by means of the magnetic object theory. The total energy losses were mathematically reconstructed and compared with those, measured experimentally.

Residual stresses in magnetic materials, whether the result of processing or intentional loading, leave their footprint on macroscopic data, such hysteresis loops and differential permeability measurements. A Preisach-type vector model is used to reproduce the phenomenology observed based on assumptions deduced from the data: internal stresses lead to smaller and misaligned grains, hence increased domain wall pinning and angular dispersion of local easy axes, favouring rotation as a magnetization reversal mechanism; misaligned grains contribute to magnetostatic fields opposing the direction of the applied field. The model is using a vector operator which accounts for both reversible and irreversible processes; the Preisach concept for interactions for the role of stress related demagnetizing fields; and a characteristic probability density function which is constructed as a weighed sum of constituent functions: the material is modeled as consisting of various subsystems, e.g. reversal mechanisms or areas subject to strong/weak long range interactions and each subsystem is represented by a constituent probability density function. Our assumptions are validated since the model reproduces the hysteresis loops and differential permeability curves observed experimentally and calculations involving rotating inputs at various residual stress levels are consistent and in agreement with experimental evidence.

In this paper a phenomenological approach, based on a generalization in two dimensions of the classical scalar Preisach model, is exploited and identified to reproduce the magnetization curves obtained by accurate micromagnetic simulations of both isotropic and anisotropic polycrystalline Fe–Si films with different values of the anisotropy constants. The identification problem is realized using a suitable set of analytical equations and performing a best fit procedure to the data obtained from micromagnetic simulations of both scalar and rotational loops. The correct reconstruction of all the magnetization processes, as well as of the associated magnetic losses, is achieved through the choice of a small number of either circular or elliptical hysterons, as well as by the implementation of a simple “moving technique” that is necessary to take into account the non-collinearity between the field and the magnetization that occurs in presence of a global uniaxial anisotropy.

This paper deals with the implementation of an energy-consistent ferromagnetic hysteresis model in 2D finite element computations. This vector hysteresis model relies on a strong thermodynamic foundation and ensures the closure of minor hysteresis loops. The model accuracy can be increased by controlling the number of intrinsic cell components while parameters can be easily fitted on common material measurements. Here, the native h-based material model is inverted using the Newton-Raphson method for its inclusion in the magnetic vector potential formulation. Simulations are performed on a 2D T-shaped magnetic circuit exhibiting rotational flux. By way of validation, results are compared with those obtained with the dual magnetic scalar potential formulation. A very good agreement for global quantities is observed. ispartof: IEEE Transactions on Magnetics vol:52 issue:3 pages:1-4 ispartof: location:CANADA, McGill Univ, Montreal status: published

Amorphous ferromagnetic Fe-based microwires (MWs) have a magnetic structure consisting mainly of a single longitudinal domain and small closure domains at both ends. A rectangular hysteresis loop is then observed according to the fast domain wall propagation along the microwire. This type of material is a good physical example of the idea of a magnetic relay hysteron as described in Preisach model of hysteresis. The hysteron was defined as a mathematical operator acting on the field and producing rectangular loops whose superposition gives out the hysteresis loop. The hysteron idealization is frequently used to describe and interpret FORC (First Order Reversal Curve) diagrams by comparison with Preisach plane. The central idea of this work is to study the FORCs of a real physical sample that behaves closely to the ideal hysteron, both isolated and interacting with a twofold aim. On one hand, providing a better understanding of FORC measurements, and, on the other, analyzing the magnetization reversal processes in microwires with rectangular hysteresis loops. While for a single microwire the behaviour is that expected for a hysteron, both in the hysteresis loop and in the FORC diagram, the magnetostatic interaction between two microwires breaks with the ideal behaviour due to the change in the domain wall mobility at the end of the wires.

The measurement of core losses in machine laminations reveals a fundamental difference between rotational and pulsating types. Rotational core losses under rotating fields decrease at high flux density, while pulsating losses keep increasing steadily. Experimental analyses of loss components Px and Py in x and y directions with rotating fields show that the loss decreases in one loss component and sometimes attains negative values. Tracking the evolution of hysteresis loops along this loss component discloses a peculiar behavior of magnetic hysteresis, where the loop changes its path from counterclockwise to clockwise within a cycle of magnetization process, the so called interleaved hysteresis loop. This paper highlights a successful procedure for modeling the interleaved hysteresis loop in the measurement of rotational core losses in electrical machine laminations using the generalized Prandtl–Ishlinskii (PI) model. The efficiency of the proposed model is compared to Preisach model. Results and conclusion of this work are of importance toward building an accurate model of rotational core losses.

This study presents a new model using the combination of Preisach and Hyperbolic Tangent models, to predict the magnetic hysteresis of Terfenol-D at different frequencies. Initially, a proper experimental setup was fabricated and used to obtain different magnetic hysteresis curves of Terfenol-D; such as major, minor and reversal loops. Then, it was shown that the Hyperbolic Tangent model is precisely capable of modeling the magnetic hysteresis of the Terfenol-D for both rate-independent and rate-dependent cases. Empirical equations were proposed with respect to magnetic field frequency which can calculate the non-dimensional coefficients needed by the model. These empirical equations were validated at new frequencies of 100 Hz and 300 Hz. Finally, the new model was developed through the combination of Preisach and Hyperbolic Tangent models. In the combined model, analytical relations of the Hyperbolic Tangent model for the first order reversal loops determined the weighting function of the Preisach model. This model reduces the required experiments and errors due to numerical differentiations generally needed for characterization of the Preisach function. In addition, it can predict the rate-dependent hysteresis as well as rate-independent hysteresis.

This paper shows that a Preisach engine, based on the classical Preisach model of hysteresis and identified using the Everett integrals and the first-order reversal curves, can be used whatever the orientation of the hysteresis loop [counterclockwise or clockwise] and whatever the monotonicity of the branches (increasing/decreasing). This is important for the use of the Preisach model in many innovative applications, such as hysteresis compensators in magnetostrictive devices and lithium-iron-phosphate rechargeable battery, as both the applications are characterized by clockwise hysteresis loops and strictly increasing loop branches. Numerical simulations of both cases, compared with experimental data, prove the validity of the approach.

A magnetic hysteresis model is developed based on the vector generalization of Jiles–Atherton (JA) model combined with a simplified multiscale approach to take into account the effect of mechanical stress on the magnetic behavior. The model aims at representing electrical steel behavior under any loading configuration considering the magnetic field vector and the mechanical stress second-order tensor. Mechanical stress is introduced in the JA hysteresis model through the anhysteretic magnetization and a modified pinning parameter. The main properties of the model are shown under alternating and rotating applied induction, especially in terms of hysteresis losses. The differential magnetic susceptibility is derived from the model, and the implementation into a time-stepping finite-element method is detailed. Finally, a quasi-statically rotating switched reluctance motor is studied: considering different shrink-fitting conditions, the resulting stress is shown to have a significant effect on both distribution and global value of hysteresis losses.

In this article, a new mathematical model of a major hysteresis loop and a simple procedure for the formation of first-order and higher-order reversal curves are proposed. The applicability of the model has been tested by comparison with measured results, obtained with electrical steel and ferrite cores, and simulation results obtained with the Preisach model. Very good agreement has been found between simulated and measured major and minor hysteresis loops, as well as first-order and higher-order reversal curves.

The laminated core is tested under sinusoidal and dc-biased magnetizations. The measured data are manipulated by the proposed modified iterative method to obtain dc-biasing hysteresis loops accurately. The hysteresis model, based on a consuming function, is used to simulate the hysteresis effects of the iron core under different magnetizations. The fixed-point technique is combined with the harmonic-balanced method to compute exciting currents and magnetic fields simultaneously by considering the hysteresis effects. The global convergent strategies are presented to guarantee the convergence of harmonic solutions. The hysteretic characteristics and iron loss of the laminated core are analyzed on the basis of harmonic solutions of the magnetic field.

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.

© 2017 IEEE. This paper introduces a comparative study of two different hysteresis models, limiting loop model and elemental operator model. The former is regarded as a mathematical approach based on the traditional Preisach model. To circumvent the difficulty of determining the distribution function in the Preisach model, the data of the limiting hysteresis loop and a function transform on the Preisach diagram are employed. The latter is a physical method which adopts a vectorial elemental operator with biaxial anisotropy based on the magnetization mechanisms of the ferromagnetic material. These two models are analyzed and compared in terms of the underlying principle, numerical implementation, and calculation accuracy in this paper. To verify the introduced models, the magnetic properties of non-oriented silicon steel Lycore-140 and soft magnetic composite material Somaloy 500 under alternating excitations are measured and compared with simulated results, which show the validity and practicability of the models but with different calculation accuracy and speed.

This paper presents a predictive and easily implementable hysteresis model for ferromagnetic laminations subjected to various quasi-static magnetic loads. In this model, the description of magnetic hysteresis is based on the decoupling of the magnetic field strength in a reversible and irreversible part, unlike in the Jiles-Atherton model. Thereby, the source of problems originating in the assumption that total magnetization could be split into the reversible and the irreversible component is bypassed. It should be stressed that models based on field separation principles are consistent with the laws of thermodynamics. The presented model allows for a systematic parameter identification based on standard magnetic measurements. In this paper, the variation of model parameters on the shape of the modeled hysteresis loop is presented. Furthermore, parameter identified from the major loop are applied to model symmetric minor loops that are evaluated by comparison with measurements. The structure of the model enables an inclusion of eddy-current effects, and is ready for a further exploitation in the FE modeling of macroscopic devices.

Ferromagnetic hysteresis behavior is a lagging relation between magnetization and external magnetic field. This understanding is useful for designing highly efficient magnetic applications e.g., magnetic recording devices. A magnetic phase and hysteresis properties fluctuate clearly when encountered with thermal noise. This creates difficulties in predicting and modeling; and poses a very challenging problem. In this study, we propose to fit parameters and select the suitable kernel functions of Support Vector Machine, of which the main tasks are i) managing the relationship among hysteresis properties, temperature, magnetic field, and magnetic frequency, and ii) classifying the symmetries of hysteresis. The results present a new novel of classifying symmetric behavior of hysteresis with high accuracy.

A phenomenological constitutive model is presented to describe the magnetization curve within the context of thermodynamics. Due to the phenomenological analogy between the magnetic hysteresis and the stress hysteresis, the basic structure of the proposed model comes from rate-dependent plasticity in continuum mechanics, namely viscoplasticity. The total magnetic flux density is assumed to be the sum of reversible and irreversible parts. The model introduces the evolution laws of two internal state variables to incorporate the effect of the ever-changing internal microstructure on the current state. The conception originated from viscoplasticity enables the frequency dependence of the hysteresis curve to be modeled.

Magnetic materials with large coercive force and high squareness ratio are currently developing to meet an industrial demand. Since a ferromagnetic material has hysteresis characteristics, it is hard to demagnetize a ferromagnetic material precisely. In this paper, we describe deperm processes and conduct an analysis of residual magnetization of ferromagnetic material using the Preisach modeling with a two-dimensional finite elements method (FEM). From the results, it was shown that an exponential decrement form of deperm protocol is more efficient than a linear decrement form because of the demagnetizing field in the ferromagnetic material.

The main objective of this work is to study and interpret the time dependence of the ferroelectric polarization in the case of a periodic variation of the electric field. It is assumed that the period of oscillations is much longer than the characteristic relaxation time of a ferroelectric. For the process description, we have employed the Landau-Khalatnikov equation for which it is possible to derive an approximate solution. The developed approach has been used for analyzing the influence of the passive layer and presence of the Kittel domain structure on the hysteresis curve.

In this paper, we discuss the numerical modeling of hysteresis in magnetic steels with oriented and nonoriented grain. The modeling is fully 3-D, but it is applied here to typical 2-D magnetic problems. Starting from a vector generalization of the Preisach model, we introduce here the concept of an operative magnetic field, function of the state of magnetization of the material. This operative field is introduced to reproduce with more accuracy the peculiar behavior of Si-Fe steels approaching the saturation state. The properties of the model are discussed and some examples are reported.

In this paper, we present a benchmark problem for the validation of numerical models of vector magnetic hysteresis. The problem geometry and the measurement system are described. The materials considered are both oriented grain (OG) and not OG Si-Fe steels. A series of experimental data about magnetic field and magnetic induction loci under rotational magnetization are presented with the corresponding magnetic losses. The measured data can be useful as a reference for the numerical models testing, comparison, and development. In addition, we propose here a comparison of the experimental data with the numerical results computed using a vector hysteresis model based on the extension of the Preisach model in 2-D.

Irreversible thermal demagnetization effects can sometimes play a significant role in, for instance, rotating Preisach model (PM) machines. Modeling such phenomena requires field simulation methods such as finite element (FE) analysis in combination with a temperature-dependent vector hysteresis model. This paper explores the feasibility of applying a formalism for temperature-dependent structural hysteresis to magnetics. The net magnetization is expressed as a superposition of contributions from plays. By allowing the anhysteretic curve and the coercivity to depend on temperature, irreversible thermal effects resembling experiments emerge automatically without additional assumptions or adjustable parameters. Incorporating this temperature dependence has negligible impact on the computational efficiency or complexity of the model.

Iron parts of electrical machines are made of nonoriented isotropic ferromagnetic materials. The finite element method (FEM) is usually applied in the numerical field analysis and design of this equipment. The scalar Preisach hysteresis model has been implemented for the simulation of static and dynamic magnetic effects inside the ferromagnetic parts of motors. The dynamic model is an extension of the static one; an extra magnetic field intensity term is added to the output of the static inverse model. This is a viscosity-type dynamic model. The fixed point method with stable scheme has been realized to take frequency-dependent anomalous losses into account in FEM. This scheme can be used efficiently in the frame of any potential formulations of Maxwell's equations. The comparison between measured and simulated data using a toroidal core shows a good agreement. A modified nonlinear version of T.E.A.M. Problem No. 30.a is also shown to test the hysteresis model in the FEM procedure.

A generalized Jiles–Atherton model is proposed to describe mixed clockwise and counter-clockwise hysteresis loops. While it is physically inconsistent for homogeneous magnetic materials, this mixed type of hysteresis is exhibited by several multi-layer and superlattice materials with antiferromagnetic coupling. The modeling approach is based on a newly developed clockwise hysteretic model using the Jiles–Atherton framework and its linear superposition to the classical counter-clockwise version. The resulting technique is implemented in open-access academic software for hysteresis and simulation samples are presented in the paper.

In this work, the Preisach technique was employed to characterize temperature dependent hysteresis loops extracted from the Ising model considered under the mean-field (MF) framework. In constructing the Preisach densities for these MF loops, a stochastic process was used to optimize the hysterons’ weight. Then, from the obtained Preisach densities, series of the MF hysteresis loops were accurately re-constructed, and the temperature independence of densities was observed. In addition, an increase of reversible polarization and a decline of irreversible polarization with increasing temperature were evident. These phenomena were examined and found to be caused by the enhancement of thermal fluctuation at higher temperature, which alleviates the spin flipping viscosity and lessens the phase-lag in hysteresis characteristic.

In this paper, a novel direct method of recursive identification of the Preisach hysteresis density function is proposed. Using the discrete dynamic Preisach model, which is a state-space realization of the classical scalar Preisach model, the method is designed based on the output increment error. After giving the general formulation, the identification scheme implemented for a discretized Preisach plane is introduced and evaluated through the use of numerical simulations. Two cases of Gaussian mixtures are considered for mapping the hysteresis system to be identified. The parameter convergence is shown for a low-pass filtered white-noise input. Further, the proposed identification method is applied to a magnetism-related application example, where the flux linkage hysteresis of a proportional solenoid is assumed from the measurements, and then the inverse of a standard demagnetization procedure is utilized as the identification sequence.

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.

This paper proposes a different inverted hysteresis model with modification of the classic Preisach switch operator. By using this new switch operator, the inverted model remains the wiping out and congruency properties. It also guarantees the symmetry and total positiveness of weight function in the Preisach plane. According to the change pattern of H(B) branches, a differentiable weight function is introduced in the inverted model. The weight function performs with good continuity and symmetry. This makes it possible to implement the inverted model in numerical analysis without iterative procedure. The identification work is done by means of the measured major loops. Here the Newton method algorithm is applied to optimize the mean squared error (MSE) between the measured and simulated data. By this way, the limited number of parameters can be determined. The inverted model was verified for both soft and hard magnetic materials. Besides major hysteresis loops, minor loops and first-order reversal curves (FORCs) can also be simulated. By comparison, the simulation results produced by the inverted hysteresis model show good approximation to the measurement data.

In this paper, a study on the demagnetization of ferromagnetic materials is conducted based on both experiments with magnetic treatment facility (MTF), which is a miniaturized experimental model, and numerical analysis methods in which the static magnetic finite-element method and Preisach model are combined. The magnetic hysteresis phenomenon inside ferromagnetic materials is effectively mimicked by means of Preisach model. However, owing to the use of $M\hbox{-}H$ variables, Preisach model generally bears numerical instability during repetitive computations. A Preisach model with $M\hbox{-}B$ variables is proposed in this paper to resolve the numerical instability. From the proposed Preisach model with $M\hbox{-}B$ variables, analysis results that were tantamount to those from the general Preisach model with $M\hbox{-}H$ variables were obtained. Numerical instability was also resolved by the proposed model. Furthermore, the discrepancy was practically negligible between the experimental result from a practical demagnetization process and the numerical analysis result from the proposed Preisach model with $M\hbox{-}B$ variables, under the same conditions.

A method for the analysis of high-speed hysteresis micromotor by using a magnetostatic field solution and Piece-Wise-Linear (PWL) model of scalar static hysteresis is presented. The solution of the magnetic field in the active layer of the hysteresis motor is performed by a two steps approach: nonlinear on the whole motor domain and hysteretic on the rotor one, the two solutions are coupled by boundary conditions. The main aim of the work is to evaluate the effect of the hysteresis of the hard magnetic material (Vicalloy 52KF7) on the magnetic field distribution, on the hysteresis losses and to provide comparison with experiments.

A new general typology of optimization algorithm inspired to classical swarm intelligence, the Continuous Flock-Of-Starlings Optimization (CFSO), is used to face the inverse problem of modeling magnetic materials. It is obtained by translating the numerical swarm/flock-based algorithms into differential equations in the time domain and employing analytical closed-forms written in the continuum. The modeling of magnetic hysteresis is very important for the development of magnetic materials and the accurate design of electrical machines. Recently several hysteresis vector models have been proposed and discussed; one of them is the Vector Hysteron Model (VHM) which is a natural extension of the Preisach theory to the vector case. In this work we present a CFSO based approach for the identification of VHM in order to reproduce scalar and rotational hysteresis loops. Experimental validations are made for both NOG (Not oriented grain) and OG (Oriented grain) steels.

A new hysteresis operator for the simulation of Goss-textured ferromagnets is here defined. The operator is derived from the classic Stoner–Wohlfarth model, where the anisotropy energy is assumed to be cubic instead of uniaxial, in order to reproduce the magnetic behavior of Goss textured ferromagnetic materials, such as grain-oriented Fe–Si alloys, Ni–Fe alloys, and Ni–Co alloys. A vector hysteresis model based on a single hysteresis operator is then implemented and used for the prediction of the rotational magnetizations that have been measured in a sample of grain-oriented electrical steel. This is especially promising for FEM based calculations, where the magnetization state in each point must be recalculated at each time step. Finally, the computed loops, as well as the magnetic losses, are compared to the measured data.

The modeling of dynamic hysteresis loops of soft magnetic materials is carried out using extended hyperbolic model. The extension is based on pure phenomenological approach and consists in elliptical component addition. This component features rounded shapes of dynamic hysteresis loops at low intensities of magnetization and it needs two parameters only. Fitting parameters for each loop are searched individually, and their dependences are then approximated by rational functions. The final model operates with approximated parameters. Proposed model was tested for the material FeNi47Cu5 at sinusoidal excitation at frequency 50 Hz.

This paper discusses the implementation of the inverse Jiles-Atherton vector hysteresis model with 2-D finite element (FE) method for the analysis of a hysteresis motor electromechanical behavior. A differential reluctivity tensor couples the hysteresis model with the magnetic vector potential-based FE model. Simulation results are validated by experimental data obtained from a specially designed machine.

In this paper, the identification of soft magnetic B - H characteristics when using the single measured hysteresis loop and fitting the discrete dynamic Preisach (DDP) model is addressed. The magnetic measurements with primary and secondary windings are performed to obtain the magnetostatic system response. The constrained least-squares estimation of the Preisach density function yields the global solution even for limited hysteresis data. The uncertainties detected during the measurement and computation of B and H values are discussed.

This paper deals with the computation of hysteresis torque in electric machines by means of the hysteresis Preisach model in finite element methods. In most cases, core loss is divided into hysteresis loss and eddy current loss. However, this component experiences mostly hysteresis loss at low speed. This hysteresis loss acts on the braking torque with cogging in the permanent magnet motor. In order to analyze the hysteresis torque, the Preisach hysteresis model is applied to the post-processor using the finite element method. In this method, computation errors can occur more than with the existing analysis method, but this method can compute hysteresis torque without complex nonlinear analysis. The hysteresis torque that is bearing friction is compared with test results. Both simulations and experiments are performed to verify the validity of the proposed method.

We present a new model for the simulation of the hysteretic large-signal behavior in ferroelectric materials. The model is based on the Preisach operator and takes advantage of an analytic weight function for the underlying fundamental switching operators. The five independent parameters describing this weight function have been determined for a discoidal piezoceramic actuator by adapting the model output to measurements of the polarization. Since the classical Preisach model is only valid for creep- and rate-independent hysteresis loops, it is inappropriate to describe the entire ferroelectric material behavior. Therefore, we extended our model by an additional drift operator to consider creep phenomena. Furthermore, the rate-dependence of the hysteresis loops is described by a frequency-dependent parameter of the analytic weight function. For the identification and verification of the model, measurements have been performed using two different measurement principles: A modified Sawyer–Tower circuit as well as a method based on the integration of the electrical current. The agreement between measurements and simulations highlights the benefits of the enhanced hysteresis model.

This paper introduces a differential approach to model scalar hysteresis based on the Preisach theory. This model can generate hysteresis trajectories for both symmetrical and asymmetrical minor loops and keep the memory of a material in a proper manner. It can easily be inverted, it has a simple algorithm with suitable computational speed, and is not memory consuming. Also, the obtained results of the model are in very good agreement with measurements.