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    Modified JilesAtherton model and parameters identification using falseposition method

    M. Hamimid a,b,, M. Feliachi a, S.M. Mimoune b

    a IREENA-IUT, CRTT, 37 Boulevard de lUniversite, BP 406, 44602 Saint Nazaire Cedex, Franceb Laboratoire de modelisation des systemes energetiques LMSE, Universite de Biskra, 07000 Biskra, Algeria

    a r t i c l e i n f o

    Article history:

    Received 10 December 2009Accepted 12 January 2010

    Keywords:

    Hysteresis

    Classical and modified JilesAtherton

    model

    Parameters identification

    False position method

    a b s t r a c t

    In this paper, a modified JilesAtherton model is proposed. This model uses a physical meaning by

    introducing the magnetizationMinstead of the irreversible magnetization Mirrin the effective magneticfieldHe-magnetic fieldHrelationship. The false position method is coupled to the iterative algorithm to

    identify the JilesAtherton parameters for both classical and modified JilesAtherton model. These

    parameters are evaluated by the resolution of three nonlinear equations obtained from three

    conditions. The validity of the modified model is done by comparing the obtained hysteresis loops to

    the experimental ones.

    & 2010 Elsevier B.V. All rights reserved.

    Contents

    1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1947

    2. Modified JilesAtherton hysteresis model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1948

    3. Determination of the modified JilesAtherton parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1948

    4. Identification technique. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19495. Results and discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1949

    6. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1950

    Work context. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1950

    Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1950

    References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1950

    1. Introduction

    Different models have been proposed to describe the hyster-

    esis phenomenon[13]. Some of them are physical in nature[1,2]

    and others ignore the physical behavior of materials [3]. Amongthe physical models, the JilesAtherton is the most and widely

    used[1].

    To evaluate the effective magnetic field, Jiles and Atherton use

    the irreversible magnetization instead of the total magnetization

    to derive a simplified formula of the total differential suscept-

    ibility [4]. Our purpose in this work is to present a modified

    JilesAtherton (MJA) model to take into account the total

    magnetization to evaluate the equivalent magnetic field. The

    expression of the total differential susceptibility obtained from

    this modification is completely different to that obtained by Jiles

    and Atherton (JA). The integration of this model in a calculationcode requires the knowledge of the exact parameters. The

    parameters of both models JA and MJA require an identification

    technique. Several techniques are used to identify the JA model

    parameters [59].

    In this work, we have used a technique which combines an

    iterative algorithm and a false position method FPM for both

    models. The parameters that we want to identify in the MJA are

    grouped into three nonlinear equations and solved by the FPM.

    This technique needs some measurements data such as the

    initial, the coercive and the remanence susceptibilities. It requires

    also the introduction of the coercivity field intensity, the remanence

    magnetization and the coordinates of the saturation point.

    ARTICLE IN PRESS

    Contents lists available atScienceDirect

    journal homepage:www .elsevier.com/locate/physb

    Physica B

    0921-4526/$- see front matter& 2010 Elsevier B.V. All rights reserved.

    doi:10.1016/j.physb.2010.01.078

    Corresponding author at: IREENA-IUT, CRTT, 37 Boulevard de lUniversite, BP

    406, 44602 Saint Nazaire Cedex, France.

    E-mail addresses: [email protected] (M. Hamimid), mouloud.

    [email protected] (M. Feliachi),[email protected] (S.M. Mimoune).

    Physica B 405 (2010) 19471950

    http://-/?-http://www.elsevier.com/locate/physbhttp://localhost/var/www/apps/conversion/tmp/scratch_3/dx.doi.org/10.1016/j.physb.2010.01.078mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]://localhost/var/www/apps/conversion/tmp/scratch_3/dx.doi.org/10.1016/j.physb.2010.01.078http://www.elsevier.com/locate/physbhttp://-/?-
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    Experimental results of the hysteresis loops are conducted to

    validate the MJA model with comparison to the JA model.

    2. Modified JilesAtherton hysteresis model

    In the JilesAtherton model, the magnetization M is decom-

    posed into reversible component Mrev, representing the transla-

    tion and the reversible rotation of the walls within ferromagneticmaterials, and the irreversible componentMirrwhich corresponds

    to domain wall displacement against the pinning effect, M MrevMirr. In their model, Jiles and Atherton suppose that the

    magnetization M is equivalent to the irreversible magnetizationMirrin the relation which binds the magnetic effective fieldHeand

    the magnetic field H:

    He HaMirr 1

    In this relation, they suppose that the reversible magnetization is

    negligible compared to the irreversible magnetization Mirr and

    they obtained the differential irreversible susceptibility in the

    simplified form:

    dMirr

    dH

    ManMirr

    kdaManMirr 2

    And finally they determined the total differential susceptibilitydM=dH in the usually form:

    dM

    dH

    1cManMirr

    kdaManMirrc

    dManHe

    dH 3

    The hypothesis of neglecting Mrev in the relation (1) has not a

    physical meaning and conduct to imprecisely result in general

    case. Our purpose is to use the physical relation relating the

    magnetic effective field He and the magnetic field H:

    He HaM 4

    By using Eq. (4) the differential irreversible susceptibility is

    obtained as

    dMirrdH

    ManMirr 1acdMandH

    kda1cManMirr

    5

    We can see clearly that ifc=0 in Eq. (5) this relation becomes as

    the same form as Eq. (2) because the parameter cis related to the

    reversible magnetization as

    Mrev cManMirr 6

    After several manipulations, given in Appendix A, we arrived

    at the following relation of magnetic total differential suscept-

    ibility:

    dM

    dH

    1cManMirr kcddMandHe

    kda1cManMirrkcaddMan

    dHe

    7

    As we can see, this relation (7) of MJA model is completely

    different from the relation (3) of JA model.

    3. Determination of the modified JilesAtherton parameters

    The total differential susceptibility can be written by using

    1cManMirr ManMas

    w dM

    dH

    ManM kcddMandHe

    kdaManMkcaddMan

    dHe

    8

    or

    w Z

    kdaZ 9

    with the following complementary relationships:

    Z ManM kcddMandHe

    10a

    Man Ms coth He

    a

    a

    He

    10b

    dMandHe

    Ms

    a 1coth2

    Hea

    a

    He

    2 ! 10c

    d 1;

    dH

    dtZ0

    1;dH

    dto0

    8>>>: 10d

    The parameters of the MJA model have different expressions

    compared to those of JA model and are determined from

    experimental data using the differential susceptibilitywinat initialpoint (H=0,M=0), the differential susceptibility wrat remanence

    point (H=0, M=Mr), the differential susceptibility wc at thecoercive point (H=Hc, M=0) and the differential susceptibility

    wmat the loop tip (H=Hm, M=Mm).From these measured magnetic properties, the parameters

    governing the hysteresis equations are obtained from the new

    expression of the total differential susceptibility (9).

    The initial susceptibility is calculated at the initial point (H=0

    andM=0) of the initial magnetization curve with d=+1:

    win dM

    dH

    H 0; M 0

    ZinkaZin

    11

    The parameter c is associated to the reversible magnetization, at

    the beginning of the initial magnetization curve and is deter-mined using the initial susceptibility

    With

    dMandHe

    H 0;M 0

    Ms3a

    In this conditionZin kcMs=3a, whena and a are initially known,the parameter c is determined by using the Eq. (11) and is

    expressed as

    c 3awin

    1awinMs12

    At the coercive point (H=Hc, M=0) with d= +1, the differential

    susceptibilitywcis given by

    wc dM

    dH

    H Hc;M 0

    ZckaZc

    13

    with

    Zc ManHc ckdManHc

    dHe

    The relationship between the parameters k and wc is obtainedusing Eq. (13), whena,aandcare previously determined, Eq. (13)can be written as follows:

    fck Zc1awckwc 0 14

    This is the first nonlinear equation, the term Zcis function of the

    parametersk, cand a .

    M. Hamimid et al. / Physica B 405 (2010) 194719501948

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    At remanence point (H=0, M=Mr), the differential suscept-

    ibilitywris given with d= 1:

    wr dM

    dH

    H 0;M Mr

    Zr

    kdaZr15

    with

    Zr ManMrMr ckddManMr

    dHe The relationship between the parameter a and the susceptibilityat the remanence point wris given by

    fra Zr1awr kwr 0 16

    frrepresents the second nonlinear equation and is extracted from

    Eq. (15), where the term Zr is also function ofk ,a , cand a.Finally, the use of the coordinates of loop tip (H=Hm,M=Mm),

    withd= +1, the differential susceptibilitywmcan be written as

    wm dM

    dH

    H Hm ;M Mm

    ZmkaZm

    17

    with

    Zm ManHm; MmMm ckdManHm; Mm

    dHe

    The parameterais determined using the differential susceptibilitywm at the loop tip; on the other hand, parameters c, a and k areknown and the parametera is obtained by solving:

    fma Zm1awmkwm 0 18

    The last nonlinear equation is given by Eq. (18) where the termZmis function ofk ,c,a and a .

    The parameter Ms is the magnetization value at strong

    saturation. It is probably the easiest parameter to obtain; this is

    often known for a particular material; in the most cases it is given

    by the constructor of the metallic sheet.

    The parameters c, k, a and a are nonlinearly coupled. Todetermine them, we propose to solve successively the Eqs. (12),

    (14), (16), and (18) using an iterative algorithm coupled with theFPM.

    4. Identification technique

    This technique is based on the coupling of an iterative

    algorithm with the FPM to identify the parameters of both MJA

    and JA models. The expressions giving the JA model parameters

    are the same as in Ref.[4]. In the MJA the parametercis obtained

    by using Eq. (12) with a given initial values of the parameters aanda, and we introduce all of them into Eq. (14) which is resolved

    by FPM to find a first estimation ofk.

    The parametersa and a are calculated from Eqs. (16) and (18)using the same FPM. The current values ofa and a are used to

    determine the new value of the parameter c. The calculationprocess is repeated until the satisfaction of the criterion

    jcnewcold=cnewjre, wheree is a given small number.The FPM starts with two pointsaandb such thatc(a) andc(b)

    are of opposite sign, implying that the function c has at least one

    zero in the interval [a, b] [10]. The method has to produce a

    decreasing sequence of intervals [ak,bk], which all contain a zero

    ofc . In step k, the numberbk is calculated by

    bk ak akbk

    cakcbkcak 19

    Ifc(ak) andc(bk) have the same sign, thenak+1=bkand bk+1=bk,

    elsebk+1=bkandak+1=ak. This process is repeated until c(bk)E0.

    For example we calculate the parameter a with FPM using

    Eq. (19): we have from Eq. (16), fra Zr1awr kwr and we

    seek a such as f(a)=0; let start with two points a1=a anda2=bsuch asf(a1) andf(a2) are of opposite sign. In step k, the numberbk, where bk is the solution in step k, is calculated by

    1. bk akakbk=fakfbkfak,

    2. iff(ak) f(bk)40 thenak+1=bkand bk+1=bk; else bk+1=bk andak+1=ak,

    3. if |f(bk)|rethen end; else go to 1 (eis a given small number).

    5. Results and discussion

    To identify MJA and JA parameters, the algorithm proposed

    needs some measured parameters that are presented in Table 1.

    These ones are extracted from the experimental loop. The

    identified parameters are presented inTable 2.

    The JA model and the MJA model hysteresis loops, using the

    identified parameters, respectively, ofTable 1are compared to the

    experimental ones.Figs. 1 and 2show the hysteresis loops of both

    models. A good agreement between measured and simulated

    hysteresis loops is obtained for both MJA and JA models; this

    Table 1

    Parameters extracted from experiment.

    Parameters Measured

    win 184.12wm 0.0443wr 1.9725 10

    3

    wc 9.974 105

    Hm (A/m) 1.039 103

    Hc(A/m) 69.37

    Mm (A/m) 1.134 106

    Mr(A/m) 8.905 105

    Table 2

    Identified JA model parameters.

    Identified parameters JA model MJA model

    Ms(A/m) 1.18 106 1.18 106

    a (A/m) 46.858 46.9605

    k(A/m) 81.10 79.001

    a 1.4843 104 1.507 104

    c 0.0219 0.0214

    -1500 -1000 -500 0 500 1000 1500

    -1.5

    -1

    -0.5

    0

    0.5

    1

    1.5

    magnetic field H (A/m)

    magneticfluxdensityB

    (T)

    measured

    JA

    MJA

    Fig. 1. Measured and simulated magnetic flux density.

    M. Hamimid et al. / Physica B 405 (2010) 19471950 1949

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    ARTICLE IN PRESS

    shows the effectiveness of the technique used to identify modelparameters on the one hand, on the other hand we can see that

    the MJA model hysteresis loop fits better the experimental one.

    The parameters obtained by this technique have a physical

    interpretation, such as the parameter k, in the case of soft

    magnetic materials, it is like similar to the coercive field.

    6. Conclusion

    The employment of the exact expression of the effective

    magnetic field relation by using the total magnetization instead of

    the irreversible one improves the hysteresis evaluation of the

    JilesAtherton model. A technique based on iterative algorithm

    coupled with the false position method is introduced to identify

    the parameters of the MJA and the JA models to derive thehysteresis loops. These parameters are compared to the experi-

    mental data. The MJA model hysteresis loop fits better the

    experimental loop compared to the JA model hysteresis loop.

    This model can be improved by taking into account the

    dynamic behavior of soft and hard magnetic materials.

    Work context

    The present work is carried out within an AlgerianFrench

    cooperation PHI-Tassili program.

    Appendix A

    The total magnetization given by JilesAtherton is

    M MrevMirr A:1

    By using Eq. (6) the total magnetization becomes

    M 1cMirr cMan A:2

    The total differential susceptibility is given by

    dM

    dH 1c

    dMirrdH

    cdMandH

    A:3

    We can also write this susceptibility as the following form:

    dM

    dH 1c

    dMirrdHe

    cdMandHe

    dHedH

    A:4

    wheredMan=dHe is given by Eq. (10c), andHe is given by Eq. (4)

    dMirrdHe

    ManMirr

    kd A:5

    The expression (A.5) is given in Ref. [4], by insert Eq. (A.5) in

    Eq. (A.4) we obtained

    dM

    dH 1c

    ManMirrdHe

    cdMandHe

    dHedH

    A:6

    By replacing 1cManMirr ManM and dHe=dH by

    1adM=dHthe expression (A.6) becomes

    dM

    dH

    Zkd

    1a

    dM

    dH

    A:7

    Z is given by Eq. (10a).Finally the total differential susceptibility is obtained as given

    by Eq. (7).

    References

    [1] D.C. Jiles, D.L. Atherton, J. Appl. Phys. 55 (1984) 2115.[2] E. Dlala, J. Saitz, A. Arkkio, IEEE Trans. Magn. 42 (8) (2006) 1963.[3] M.L. Hodgdon, IEEE Trans. Magn. 24 (6) (1988) 3120.[4] D.C. Jiles, J.B. Thoelke, M.K. Devine, IEEE Trans. Magn. 28 (1992) 27.[5] J. Izydorczyk, J. Magn. Magn. Mater. 302 (2006) 517.[6] K. Chwastek, J. Szczyglowski, J. Magn. Magn. Mater. 314 (2007) 47.[7] E.D.M. Hernandez, C.S. Muranaka, J.R. Cardoso, Physica B 275 (2000) 212.[8] P. Andrei, L. Oniciuc, A. Stancu, L. Stoleriu, J. Magn. Magn. Mater. 316 (2007)

    330.[9] A. Salvini, F. Riganti Fulginei, IEEE Trans. Magn. 38 (2002) 873.

    [10] A. Quarteroni, A. Sacco, F. Saleri, Me thode Numeriques, Algorithmes, Analyseet Applications, Springer, 2007.

    0 200 400 600 800 1000

    0

    0.2

    0.4

    0.6

    0.8

    1

    1.2

    1.4

    magnetic field H (A/m)

    magneticflu

    xdensityB(T)

    measured

    JA

    MJA

    Fig. 2. Measured and simulated magnetic flux density (zoom up).

    M. Hamimid et al. / Physica B 405 (2010) 194719501950