• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.4
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• pp.38-51
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• 2007

This paper describes research results for the measurement and analysis method of magnetic signatures generated from the ship's magnetic mock-up model. In this paper, we present the theoretical and experimental techniques for the separation of the permanent and the induced magnetic field from the measured magnetic signature of the mock-up model. Also, we describe the prediction method of the induced magnetic field generated from mock-up model using the Magnet s/w, one of the FEM analysis tools for the electro-magnetic field and the magnetic dipole modelling method based on the least square techniques. The proposed modelling and analysis methods can be used for the prediction and the analysis of the static magnetic field generated from the real naval ship as well as the mock-up model.

• Journal of Mechanical Science and Technology
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• v.15 no.12
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• pp.1876-1881
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• 2001

We present the numerical analysis of the growth of a silicon (Si) single crystal. In the MCZ (Magnetic-field-applied Czochralski) method, two magnetic fields that stand opposite to each other generate a cusp magnetic field. In this work, the three cusp magnetic fields used for the analysis are an extern magnetic field, a surface magnetic field and an internal magnetic field. Each case was evaluated mainly as to the degree of stirring, shaft symmetry and the stability of the flow. As a result, the cusp magnetic field that yielded to best conditions was the internal magneic field.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.263-268
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• 2008

The measurement of magnetic field is performed AC magnetic field emission density in driver cab and saloon's compartment of rolling stock. In order to measure magnetic-field emission, a three-axial magnetic-field sensor is used and connected to data process system. The AC magnetic field is checked and analysis through BNC output, DAQ cad and notebook PC. The spectral analysis is performed by short time Fourier transform(STFT) for time-domain emission signal.

• Progress in Superconductivity and Cryogenics
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• v.17 no.3
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• pp.23-27
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• 2015

Quadruple magnet is an essential component for the accelerator, and the field uniformity in the good field region reflects the quality of quadruple magnet. In this paper, the total magnetic field B was separated into the coil-induced magnetic field $B_s$ and the iron-induced magnetic field $B_c$ to explain why the total magnetic field B has some inhomogeneity. Using Fourier analysis, harmonic components of $B_s$, $B_c$ and B have been analyzed at good field region, respectively. The harmonics of multipole magnet and Fourier analysis are helpful to show the uniformity of magnetic field. Several geometries of yoke and coils were defined to analyze the effect on field uniformity of an HTS quadruple magnet. By the analysis, it was found that the sixth harmonics which is the main factor of field inhomogeneity can be reduced to zero. It means that the sixth harmonics of the magnetic field B can be removed by adjusting the geometry of the magnet pole and the position of coils. We expect that this result can effectively improve the uniformity of an HTS quadruple magnet.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1637-1639
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• 2005

The measurement of magnetic field is performed about DC and AC magnetic field in test track of depot. The test point is cap, on the converter/inverter box, on the traction motor, on the APSE and on the line filter, the height of measurement is bottom and 50 cm height. In case of AC magnetic field, the selected specific frequency is measured on the converter/inverter box. The AC magnetic field is checked and analysis through RS-232C and notebook PC. The DC magnetic field is measured by using the Hall Probe, test result is saved and analysis by PXI system. On the line filter, the maximum value is 1.4 mT in case of DC magnetic field and 0.044 mT in case of AC magnetic field at 50 Hz.

• Progress in Superconductivity and Cryogenics
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• v.14 no.3
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• pp.18-22
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• 2012

This paper presents the magnetic field analysis of the racetrack double pancake field coil for the 10 MW class superconducting wind turbine which is considered to be the next generation of wind turbines using the 3 Dimensional FEM(Finite Elements Method). Generally, the racetrack-shaped field coil which is wound by the second generation(2G) superconducting wire in the longer axial direction is used, because the racetrack-shaped field coil generates the higher magnetic field density at the minimum size and reduces the synchronous reactance. To analysis the performance of the wind turbines, It is important to calculate the distribution of magnetic flux density at the straight parts and both end sections of the racetrack-shaped high temperature superconductivity(HTS) field coil. In addition, Lorentz force acting on the superconducting wire is calculated by the analysis of the magnetic field and it is important that through this way Lorentz force can be used as a parameter in the mechanical analysis which analyzes the mechanical stress on the racetrack-shaped field coil.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.10
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• pp.501-506
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• 2003

A Superconducting Rotary Machine (SRM) is characterized by an air-cored machine with its rotor iron and stator iron teeth removed. For this reason, the SRM is featured by 3D magnetic flux distribution, which decreases in the direction of axis. Therefore, 3D magnetic field analysis method is required to know about characteristic of magnetic field distribution of SRM. In this paper, 3D flux distribution of SRM is calculated by analytical method. The magnetic field distribution of the field coils is calculated by Biot-Savart equation. The magnetic core is represented by magnetic surface polarities. This paper describes the combined use of above methods for the total field computation, and compares results of analytical method and 3D FEM(Finite Element Method).

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.83-85
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• 2007

In magnetic field analysis of electrical machines, hysteresis phenomena of B-H curves should be taken into account in order to obtain more accurate results. In this paper, the hysteresis modeling using the micromagnetics for the magnetic field analysis is investigated. In the micromagnetics, usually, it takes much CPU times. Therefore, the method for representing hysteresis phenomena by minimum modeling is investigated in order to applying it to the magnetic field analysis. First, the micromagnetics is described. Then, the method of minimum modeling is shown. Finally, the hysteresis curve obtained by the minimum modeling is demonstrated. The effect of parameters of micromagnetics on the shape of hysteresis curve is investigated.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.2B no.4
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• pp.149-155
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• 2002

This paper presents magnetic field analysis technology that uses a vector magnetic characteristic. Recently the magnetic material was found to be measurable using the vector quantity technique. Therefore considering the anisotropy of the magnetic material in the vector field analysis is necessary. The magnetic field analysis method, which is considered the anisotropy by combining the finite element method with the E&$S^2$ (Enokizono, Soda, and Shimoji) modeling, is applied to a permanent magnet motor model.

• Progress in Superconductivity and Cryogenics
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• v.4 no.2
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• pp.47-51
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• 2002

In this paper, flux distribution and operating current is calculated according to the field coil change in HTS(High Temperature Superconducting) motor. In order to calculate magnetic field characteristic of the field coil. it is computed by changing the outer radius and the inner width of field coil Bio-Savart equation is used as the analysis method for the characteristic analysis of magnet. 2D and 3D FEA(Finite Element Analysis) is used for the magnetic field distribution in HTS motor The operating current is calculated by $B{\bot}$ linked With the field coil and $I_c-B curve of superconductor.