Scalar Hysteresis Model Research Articles

Tuned mass systems with the Bouc-Wen and a hybrid hysteresis

Tuned-mass-dampers are extensively used in physical systems in order to reduce the dynamic response of the primary structures. The damping in a tuned-mass-damper system plays a significant role. In many engineering systems, we see damping is hysteretic in nature. Tuned-mass systems with nonlinear hysteretic damping are mathematically challenging. In this paper, tuned mass systems with rate-independent hysteresis are studied. In particular, first we study tuned mass systems with the famous Bouc-Wen model, and then we study tuned mass systems with the Bouc-Wen model and a recently developed scalar hysteresis model in parallel. Numerical approaches are used to study the dynamic responses of the systems. The sine sweep responses show two resonance peaks. The sine sweep responses indicate the amplitude versus frequency of the systems. The numerical results obtained for two different hysteretic dampers are compared.

Anisotropic Congruency-Based Vector Hysteresis Model Applied to Non-Oriented Laminated Steels

A new approach is proposed to model the hysteretic behavior of magnetic materials in 2-D electromagnetic analyses. A scalar congruency-based hysteresis model is developed using the first-order reversal curves (FORCs) and verified by comparing the model results with quasi-static measurements. An anisotropic scalar model is obtained from two scalar hysteresis models using FORCs measured parallel and perpendicular to the material rolling direction. The established anisotropic scalar model is employed as the main building block to determine the vector hysteresis model based on the Mayergoyz vector hysteresis generalization. The obtained vector hysteresis model is coupled with a finite-element solver to analyze the three-limbed transformer core investigated in the TEAM problem number 32. The comparison between the simulation results and experimental data confirms the accuracy of the proposed model with an rms flux density error of less than 0.07 T.

Comparison and Combination of Techniques for Determining the Parameters of a Magnetic Hysteresis Model

The Jiles-Atherton scalar hysteresis model presents five parameters used to represent the material tested and used to calculate the magnetic losses. This article presents a comparative analysis of the performance of two methods of identifying these parameters. In the first method, the equations of Jiles-Atherton were assembled into a single non-linear ordinary differential equation as a function of the variables of interest. An algebraic system of five equations with five unknowns is obtained by evaluating the non-linear ordinary differential equation in five points belonging to the branch of the experimental hysteresis loop. The parameters are obtained by solving this system of equations using the method of Non-Linear Least Squares (NLLS). In the second method, the inverse model of Jiles-Atherton is used to calculate the magnetic field H from the experimental values of magnetic induction B. Using the method of genetic algorithms (MGA), the objective function given by the sum of the relative error of calculated magnetic field and experimental magnetic field along the hysteresis loop is minimized. To validate methods the experimental curves were compared with calculated ones. When applying the methods, it was verified that NLLS besides providing more accurate results, it is faster when compared to MGA. In the MGA the convergence of the calculated magnitudes to the experimental magnitudes improves when one of the chromosomes of the initial population is the solution obtained applying NLLS.

Losses Computation in Reciprocating Tubular Permanent Magnet Generator with SMC Core

Generally, the Permanent Magnet Tubular Generators (PMTG) are employed in the free-piston generator systems. In this paper, the PMTG with the core made of Soft Magnetic Composite (SMC) is employed, and then, the PMTG with the solid SMC core has cylindrical symmetry and also the outer diameter of the machine reduces in comparison to the ones with multipart laminated steel cores in which each part is radially placed along the air-gap and there is unexploited space between them. Here, a Finite Element Method (FEM) is developed in which the reciprocating motion of the translator is considered by moving mesh techniques and moreover, the Jiles-Atherton (JA) scalar hysteresis model is incorporated in the FE model to take into account the hysteresis losses. Then, the copper and core losses are computed and the equivalent circuit of the generator is derived. The calculated losses are compared with the ones obtained from the analytical methods.

Magnetic Aging Effect Losses on Electrical Steels

The magnetic losses behavior on electrical steels related to the magnetic aging is analyzed in this paper. Experimental procedures involving thermal, metallurgical, and electromagnetic measurements were performed. The evolution of the losses is modeled using a scalar hysteresis model, and the aging prediction on electrical motor steels is proposed using the Arrhenius formula. The proposed study brings relevant information to be considered on designing electrical motors.

Hysteretic damping in an elastic body with frictional microcracks

Material stress strain curves often show dissipation via rate-independent hysteresis. Here we study an elastic plate with several randomly distributed and oriented frictional microcracks, loaded cyclically in plane stress. Computational solutions in ABAQUS show narrow hysteresis loops. Unlike the loops from Rowett׳s classic experiment (1914), or from simple hysteresis models such as the Bouc–Wen model (1967 and 1976), the present loops are pinched at the origin and partially resemble an ad hoc model proposed by Reid (1956). Such pinched loops have been revisited lately by others, but our results provide new justification for the same. We also propose a new simple scalar model that gives a better qualitative match with the numerically obtained hysteresis loops than any other model presently available. Our scalar hysteresis model may lead to better interpretations and modeling in, e.g., vibration response of structures with such internal frictional damping. Thus the contribution of this paper lies in adopting a dissipation model from micromechanics, idealizing the resulting dissipation loops, and presenting a new simple scalar equation that models such loops and can be easily incorporated into structural vibration damping models.

Identification of scalar Jiles-Atherton hysteresis model parameters with a new particle behaviour based metaheuristic algorithm

Identification of scalar Jiles-Atherton hysteresis model parameters with a new particle behaviour based metaheuristic algorithm

Improvement and Application of the Viscous-Type Frequency-Dependent Preisach 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.

Non Linear Magnetic Hysteresis Modelling by Finite Volume Method for Jiles-Atherton Model Optimizing by a Genetic Algorithm

This paper describes a generalization methodology for nonlinear magnetic field calculation applied on two-dimensional (2-D) finite Volume geometry by incorporating a Jiles-Atherton scalar hysteresis model. The scheme is based upon the definition of modified governing equation derived from Maxwell’s equations considered the magnetization M. This paper shows how to extract optimal parameters for the Jiles-Atherton model of hysteresis by a real coded genetic algorithm approach. The parameters identification is performed by minimizing the mean squared error between experimental and simulated magnetic field curves. The calculated results are validated by experiences performed in an SST’s frame.

Accurate minor loops calculation with a modified Jiles‐Atherton hysteresis model

PurposeAlthough the original Jiles‐Atherton (J‐A) hysteresis model is able to represent a wide range of major hysteresis loops, in particular those of soft magnetic materials, it can produces non‐physical minor loops with its classical equations. The purpose of this paper is to show a modification in the J‐A hysteresis model in order to improve the minor and inner loops representation. The proposed technique allows the J‐A model representing non‐centred minor loops with accuracy as well as improving the symmetric inner loops representation.Design/methodology/approachOnly the irreversible magnetization component is slightly modified keeping unchanged the other model equations and the model simplicity. The high‐variation rate of the irreversible magnetization, which causes the non‐physical behaviour of minor loops, is limited by introducing a new physical parameter linked to the losses. Contrarily to other modifications of the original model found in the literature, the previously knowledge of the magnetic field waveform is not needed in this case.FindingsThe modified hysteresis model is validated by comparison with experimental results. A good agreement is observed between calculations and measurements. The modified model retains the low‐computational effort and numerical simplicity of the original one.Originality/valueThis paper shows that a classical scalar hysteresis model can be suitably used to take into account the minor loops behaviour and be included in a finite element code. The methodology is useful for the design and analysis of electromagnetic devices under distorted flux patterns.

Magnetic measurement and vector modeling under applied mechanical stress

The scope of the work is the investigation of the properties of the magnetic characteristic under applied stress. The realization and the accuracy of a Preisach-type scalar magnetic hysteresis model are displayed with respect to the changing of the mechanical stress in the magnetic material. A stress dependent isotropic and anisotropic vector hysteresis model has been developed. The model represents the main properties of the tensile stress effects on the magnetic behavior.

Spectral property of a novel hysteresis model with additive noise

In this paper the time and spectral behavior of a novel scalar hysteresis model with noise is introduced. The advantages of the novel scalar hysteresis model are its numerical simplicity, easy identification procedure and past memory representation. The noisy excitation, the magnetic field strength H is defined by its spectral components with a given signal to noise ratio (SNR). Applying a noisy bandwidth-limited excitation H into the hysteresis model it allows additional results. The aim of the analysis is to study the sensibility and the behavior of the scalar hysteresis model under noisy excitation. Furthermore the novel preparation of the anhysteretic curve from the major loop using the complex Fourier transform is discussed.

Analysis of a rotational single sheet tester using 3D finite element model taking into account hysteresis effect

PurposeThe magnetic field strength measurement in a rotational single sheet tester (RSST) is quite difficult to achieve. In fact, flux leakage perturbs the field sensors as well as the homogeneity in the sample area. This paper seeks to present a 3D finite element (FE) model of an RSST taking into account a vector hysteresis model. The use of such model allows analyzing with accuracy the magnetic behavior of the system.Design/methodology/approachA vector hysteresis model, which is based on a general vectorization of the scalar Jiles‐Atherton model, is incorporated in a 3D FE code, with vector potential formulation.FindingsThe vector hysteresis model is validated by comparison with rotational experimental results. A good agreement is observed between calculations and measurements.Originality/valueThis paper shows that a classical scalar hysteresis model can be extended to take into account the magnetic vector behaviour and can be included in a 3D FE code. The methodology for the hysteresis including in the FE formulation is shown. This is useful for the design and analysis of an RSST prototype, improving the measurement techniques.

Generalized Constructive Model of Hysteresis

We describe a generalized constructive model of rate independent scalar hysteresis. It consists of an algorithm that uses a set of experimental hysteresis minor loop vertical chords. The introduced model requires new, less constraining properties than the congruency and equal vertical chords properties required by the classical and the generalized Preisach models. Our model allows for fitting transition curves of order greater than two, despite its simple mathematical notation. Further, we describe interesting performance of the model in numerical evaluation and inversion

Two-dimensional vector hysteresis model

In this paper a new vector hysteresis model is constructed on the basis of a scalar hysteresis model. The advantages of the scalar model are its easy identification, past memory representation and numerical simplicity. The accommodation property of the model comes from the construction philosophy of the model. The feasibility of the extrapolation is defined by the turning points. The convenience of this model is its efficiency in reduction of the calculation time. The model parameters, the modification vector fields, derived from the permeability vector can be determined from the measured data points. The vector model can approximate the behavior of the vector hysteresis characteristics of ferromagnetic materials. In this paper the main question of the vector model, the definition of the initial values of components in the selected directions is solved.

Remarks about a fuzzy approach to model scalar hysteresis

This article presents a generalization of a fuzzy model (FM) of scalar hysteresis in order to describe the experimental behavior of magnetic materials when the uniform domains motion hypothesis is not satisfied. Furthermore, several remarks are made regarding the choice of the data needed for the identification problem solution. Advantages of the FM compared to the Preisach model are also presented.

Vector hysteresis measurement

Simulation of a simple arrangement and modeling the scalar hysteresis characteristics can be used advantageously when the magnetic field intensity and the magnetization are in the same direction (e.g. toroidal-shaped coil). In many cases, it is not enough to apply the scalar hysteresis model, but a more powerful and more complicated hysteresis model must be developed to describe the vector property of the field quantities. Generally, the magnetic field intensity and the magnetization vectors are not in the same direction, so applying scalar models may give inaccurate numerical results. In this paper a measuring arrangement of 2D vector hysteresis characteristics is performed, measurement results are shown in figures and discussed.

A comparative study of Preisach scalar hysteresis models

In this paper different Preisach-relays-based models are taken into account for the modeling of scalar hysteresis. The main features of such models are presented and discussed, and identification procedures are illustrated, either using complete numerical approaches, or using mixed analytical–numerical approaches. The results obtained for a non-oriented grain steel suggest that the mathematical models of scalar hysteresis taken into account have comparable predictive capabilities and accuracy.

A fuzzy model of scalar hysteresis on soft magnetic materials

This paper presents a model, based on the fuzzy logic, in order to describe scalar hysteresis modeling on magnetic materials. After a brief description of the fuzzy logic, we discuss how to identify the fuzzy model starting by the knowledge of both the experimental major loop and virgin curve data. The model will be tested on non-oriented magnetic steels. In particular, it can be used to compute minor symmetric loops of non-oriented SiFe (2% in weight). The results are in good agreement with the experimental data. Furthermore, possible generalizations are suggested.

Vector hysteresis model based on neural network

On the basis of the Kolmogorov‐Arnold theory, the feedforward type artificial neural networks (NNs) are able to approximate any kind of nonlinear, continuous functions represented by its discrete set of measurements. A NN‐based scalar hysteresis model has been constructed preliminarily on the function approximation ability of NNs. An if‐then type knowledge‐base represents the properties of the hysteresis characteristics. Vectorial generalization to describe isotropic and anisotropic magnetic materials in two and three dimensions with an original identification method has been introduced in this paper.