Improved Analytical Algorithm for Magnetic Field of end windings in 300Mvar Synchronous Condenser

This paper researches on the levitation and drag forces of Halbach permanent-magnet electrodynamic suspension. First, construct an analytical model to calculate the magnetic field in the air gap and the current in the secondary conductor plate, thus deducing analytical expressions of the levitation and drag forces. Second, establish a 2D and a 3D finite element model, using ANSYS. Finally, at different speeds, from 0 to 250 km/h, compare the forces calculating results through the above three methods. Results generating from the 2D-FEM and the analytical algorithm have less than 3% of relative error, but for having not taken the horizontal components of eddy current in the reaction plate into consideration, thus 10% more than the 3D-FEM calculating results.

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An analytical algorithm for 3D magnetic field mapping of a watt balance magnet

Metrologia ◽

10.1088/0026-1394/53/2/805 ◽

2016 ◽

Vol 53 (2) ◽

pp. 805-816 ◽

Cited By ~ 1

Author(s):

Zhuang Fu ◽

Zhonghua Zhang ◽

Zhengkun Li ◽

Wei Zhao ◽

Bing Han ◽

...

Keyword(s):

Magnetic Field ◽

Field Mapping ◽

Magnetic Field Mapping ◽

Analytical Algorithm ◽

Watt Balance

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Analysis of the Planar Magnetic Field of Linear Permanent Magnet Halbach Array

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.66-68.1336 ◽

2011 ◽

Vol 66-68 ◽

pp. 1336-1341

Author(s):

Xiao Zhang ◽

Yun Gang Li ◽

Hu Cheng ◽

Heng Kun Liu

Keyword(s):

Magnetic Field ◽

Permanent Magnet ◽

Element Analysis ◽

Magnetization Direction ◽

Halbach Array ◽

The Finite Element Analysis ◽

Analytical Algorithm ◽

Analytical Expressions ◽

The Magnetic Field ◽

A Current

In this paper, the analytical solution to the planar magnetic field of a linear permanent magnet Halbach array is researched on. First, the magnetic field of a current surface is derived from the magnetic field produced by the molecular current of the permanent magnet. The magnetic fields of pieces of permanent magnet with vertical and diagonal magnetization direction are both solved by combining the magnetic field of current surfaces with different directions. Then the planar magnetic field of the entire linear permanent magnet Halbach array is obtained by calculating the vector addition of the magnetic field of all the permanent magnet cubes using Denavit-Hartenberg (D-H) transform technique, which yields the closed-form analytical expressions. The analytical algorithm proposed in this paper can be utilized to design and optimize the Halbach array, which in result can greatly simplify the calculation and expedite the progress. The effectiveness of the proposed method is evaluated by the finite element analysis software Maxwell.

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Magnetic-field strengths from optical polarization data

Symposium - International Astronomical Union ◽

10.1017/s0074180900101263 ◽

1967 ◽

Vol 31 ◽

pp. 381-383

Author(s):

J. M. Greenberg

Keyword(s):

Magnetic Field ◽

Optical Polarization ◽

Polarization Data ◽

Term Model ◽

Source Of Information ◽

Field Strengths

Van de Hulst (Paper 64, Table 1) has marked optical polarization as a questionable or marginal source of information concerning magnetic field strengths. Rather than arguing about this–I should rate this method asq+-, or quarrelling about the term ‘model-sensitive results’, I wish to stress the historical point that as recently as two years ago there were still some who questioned that optical polarization was definitely due to magnetically-oriented interstellar particles.

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Observing the galactic magnetic field

Symposium - International Astronomical Union ◽

10.1017/s0074180900101251 ◽

1967 ◽

Vol 31 ◽

pp. 375-380

Author(s):

H. C. van de Hulst

Keyword(s):

Magnetic Field ◽

Fair Agreement ◽

Solar Neighbourhood ◽

Galactic Magnetic Field ◽

The Magnetic Field

Various methods of observing the galactic magnetic field are reviewed, and their results summarized. There is fair agreement about the direction of the magnetic field in the solar neighbourhood:l= 50° to 80°; the strength of the field in the disk is of the order of 10-5gauss.

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Structure in the radiation of the galactic disk

Symposium - International Astronomical Union ◽

10.1017/s0074180900101184 ◽

1967 ◽

Vol 31 ◽

pp. 355-356

Author(s):

R. D. Davies

Keyword(s):

Magnetic Field ◽

Galactic Disk ◽

Galactic Magnetic Field ◽

Measured Polarization

Observations at various frequencies between 136 and 1400 MHz indicate a considerable amount of structure in the galactic disk. This result appears consistent both with measured polarization percentages and with considerations of the strength of the galactic magnetic field.

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Calculated Coronal Magnetic Fields and Their Comparison with the Coronal Structures as Observed during Five Solar Eclipses

International Astronomical Union Colloquium ◽

10.1017/s0252921100026038 ◽

1994 ◽

Vol 144 ◽

pp. 559-564

Author(s):

P. Ambrož ◽

J. Sýkora

Keyword(s):

Magnetic Field ◽

Solar Cycle ◽

Magnetic Fields ◽

Solar Corona ◽

Coronal Magnetic Field ◽

Coronal Magnetic Fields ◽

Solar Eclipses ◽

Coronal Structures

AbstractWe were successful in observing the solar corona during five solar eclipses (1973-1991). For the eclipse days the coronal magnetic field was calculated by extrapolation from the photosphere. Comparison of the observed and calculated coronal structures is carried out and some peculiarities of this comparison, related to the different phases of the solar cycle, are presented.

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Faint Hα Emission in the Corona and Its Relation to the Prominences

International Astronomical Union Colloquium ◽

10.1017/s0252921100025550 ◽

1994 ◽

Vol 144 ◽

pp. 339-342

Author(s):

V. N. Dermendjiev ◽

Z. Mouradian ◽

J.- L. Leroy ◽

P. Duchlev

Keyword(s):

Magnetic Field ◽

Solar Corona ◽

Essential Role ◽

Hα Emission

AbstractThe relation between episodically observed in the solar corona faint Hαemission structures and the long lived prominences was studied. Particular consideration was given for cases in which the corresponding prominences had undergone DB process. An MHD interpretation of the phenomenon “emissions froides” (cool emission) is proposed in which an essential role plays the prominence supporting magnetic field.

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