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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. [ABSTRACT FROM AUTHOR]

This paper proposes an equivalent magnetic hysteresis (B–H) curve for magnetic multiscale problems of complex materials composed of electrical conductors separated by insulating material. The conventional method, which assigns equivalent material constants to each material, cannot properly express the local eddy current loss and the extra magnetic field derived from the local eddy current. To solve this problem, we derive the magnetic hysteresis curve from the volume-averaged magnetic flux density and the surface magnetic field in the micro-model, and apply this curve to the macro-model. The mesh number of the novel macro-model is reduced to around one-tenth that of the micro-model. Magnetic hysteresis is treated by a free energy magnetic hysteresis model, and the macro-model ignores electrical conductivity. The magnetic hysteresis curve and the numerically calculated losses are consistent in the micro- and macro-models. The proposed method well expresses the local eddy current phenomena. [ABSTRACT FROM AUTHOR]

This paper deals with the modeling of vector fields that exhibit hysteresis. A general class of models of vector magnetizations with hysteresis that form a natural extension of the Classical Scalar Preisach Model is defined. Although the modeling was done for the 2-d case, the same theory can be extended to the 3-d case as well. After reviewing some general properties of conservative fields, the specific case of unit magnitude vector fields is discussed. The paper focuses on discussing the properties of a general vector hysteresis operator (hysteron). The mathematical approach followed here can be applied not only to the magnetic hysteresis, but also to any hysteresis process. Some examples of vector hysterons, deduced from the general definition, are presented and their properties analyzed. [ABSTRACT FROM PUBLISHER]

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]

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]

Recent advances have been made into modeling the soft-magnetic materials using the surface charge model. Until now, the model has only been used to model the field outside the soft-magnetic material. To include the saturation in the future, the magnetic field inside the material should be known. In this paper, the model is used to calculate the field inside the material when three different shapes of boundaries are considered. Comparing the results with Finite Element Method shows that the differences in the air region are <1 mT and those in the soft-magnetic region are <4 mT. Larger discrepancies can, however, occur near the corner of the material. [ABSTRACT FROM AUTHOR]

The magnetic tunnel junction (MTJ) effect has been widely applied in information technology and has brought about many revolutionary products in the past decade. In the meantime, many research studies on linear magnetoresistive sensors based on MTJ have been published to improve their performance metrics, such as linear field range, sensitivity, hysteresis, and noise. Though the frequency response of high-speed magnetic reading has been researched, the performance and application of linear magnetoresistive sensors with bridge configuration for high-frequency sensing remain underexplored. In this paper, we proposed an equivalent impedance network model of packaged linear magnetoresistive sensors based on MTJ with Wheatstone bridge configuration, and derived the corresponding frequency-dependent performance model, considering the influences of the parasitic capacitances and the amplitude of the applied magnetic field. Our work shows that the frequency characteristics of linear magnetoresistive sensors are closely associated with their $RC$ time constants, which depends on their resistances and parasitic capacitances. The useful bandwidth of an MTJ linear sensor is also related to the amplitude of the applied magnetic field. The bandwidth changes negligibly with the varying magnetic field in the range of less than 30% of the saturation field, but increases rapidly when it exceeds 30% of the saturation field. [ABSTRACT FROM AUTHOR]

In this paper, we present a 3-D numerical model of an integral formulation for the efficient computation of 3-D magnetic fields in hysteretic media with (time) periodic sources. The hysteretic medium is described by an isotropic vector generalization of the classical scalar Jiles–Atherton model. The nonlinear algebraic system is solved using Picard–Banach iterations in the frequency domain. The full matrices arising after the discretization of the main (linear) operators are suitably compressed and distributed among the nodes of a parallel computer system. The numerical model is applied for the nondestructive micromagnetic characterization (of mechanical properties) in metallic materials. In particular, the problem of estimating incremental permeability is analyzed. [ABSTRACT FROM AUTHOR]

This paper describes the magnetic field analysis of a ring core taking account of hysteretic properties of magnetic materials by the play model. The numerical results are compared with the measured results to demonstrate the effectiveness of the play model and some features of the play model due to its rate-independent properties are discussed. Furthermore, the novel time-periodic explicit error correction method suitable for the magnetic field analysis taking account of the hysteretic property by the play model is proposed for the improvement of the convergence to the steady state in the time-periodic transient analysis. [ABSTRACT FROM PUBLISHER]

In this work we present a physical-related model of vector hysteresis for magnetic simulation of nanometric structures. The mathematical formulation, based on a generalization of the Preisach and Stoner-Wohlfarth models, is very simple and elegant. The numerical implementation is very easy and the computation time required for the simulations is extremely fast. However the accuracy is not comparable with the codes based on the micromagnetic theory, but it is sufficient for the use as preprocessing of more accurate and more complex methods, in order to speed up the convergence. In this paper the model identification is performed for a nanoscale spin valve using the data generated by a 3D micromagnetic code. [ABSTRACT FROM AUTHOR]

The paper proposes an improved analytical model, valid for a wide frequency range, of interlaminar short-circuits on the edges of the sheets of high power transformers working at 50–60 Hz. This model is able to determine the current flowing in the microscopic interlaminar contacts formed by burrs, in order to estimate the maximum power dissipated in such hot spots. With this theoretical approach, it is also possible to get an interpretation of impedance measurements on a test coil wound around the core, in order to define a new index able to characterize the part of the shearing burrs in the manufacturing factor of large transformer cores. This new index will help the transformer manufacturers to improve their processes. [ABSTRACT FROM PUBLISHER]

This paper presents a method for calculating eddy current loss based on reluctance network analysis (RNA) considering the magnetic reaction field caused by the eddy current. First, an electric network model for calculating eddy current is indicated. Next, RNA model considering the magnetic reaction field by using magnetic inductance is presented. The validity of the proposed model is proved by comparing with the finite-element analysis and experiment. [ABSTRACT FROM AUTHOR]

In this paper, the effect of a symmetric distribution of dipolar fields acting along the applied field on the magnetization curve of a superparamagnetic nano-granuler system is examined. The calculations show that the magnetization curves are depressed when the spread of dipolar fields is increased. This reduction in magnetization is attributed to the nonlinear response of magnetization which weighs negative dipolar fields more strongly than the positive dipolar fields. Thus, the reduction in magnetization is not indicative of a predominant negative interaction field, since positive and negative fields are equally probable. Also, for the system examined, the nonlinear response of magnetization is responsible for the predicted negative average ordering temperature in the temperature variation of the initial susceptibility. Thus, in random systems, the interpretation of a negative ordering temperature as antiferromagnetic order, or the positive ordering temperature as a ferromagnetic order should be cautiously stated. [ABSTRACT FROM AUTHOR]

This paper shows that two apparently independent models of hysteresis-the Jiles-Atherton model, developed by Jiles and Atherton, and the energetic model, developed by Hauser-are mathematically equivalent. These two hysteresis models are examined with respect to their capability to describe the dependence of the magnetization on magnetic field and mechanical stress. Comparisons have been made between the predictions of the two models and measured hysteresis curves. Through a mathematical analysis of the structure of the models, conditions have been found under which both models predict the same magnetization curves. This "common ground" agreement between the models has allowed us to establish correspondence between the descriptors of the models so that a mathematical transformation between the model parameters becomes possible. The result allows improved interpretation of the physical mechanisms that contribute to ferromagnetic hysteresis at different stages in the magnetization curve in terms of the reversible and irreversible physical processes such as domain wall motion and domain rotation which form the basis of these models. Furthermore, consideration of the internal demagnetizing factor has also allowed it to be included in the models. [ABSTRACT FROM PUBLISHER]