• Journal of the Korean Magnetics Society
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• v.7 no.4
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• pp.180-185
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• 1997

Variations of core loss and coercivity with heat treatment condition have been studied in amorphous ribbon core specimens. All measurements were performed at 10 kHz with a maximum induction of 0.1 T. With increasing annealing time, both core loss and coercivity of core specimens decreased first, reaching minimum values, and increased thereafter. Specimen heat treated in an air showed better soft magnetic properties than those treated in Ar atmosphere. The specimens annealed under magnetic field higher than 6 Oe in radial direction showed reduced core loss and coercivity. The field annealing effects were increased with increasing cooling rate near Curie temperature of the material. The specimen annealed under an applied field in perpendicular direction of the core showed increased coercivity and decreased permeability.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.110-112
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• 1998

Some recomendations for the manufacturing, operation and maintanance of amorphous alloy core transformer are presented through the operation experiance. Transformers on trouble was taken to pieces and tested from a viewpoint of durability, and low loss characteristics.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.144-146
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• 1994

We manufactured amorphous core for 1 KVA transformer by lap-step and one cut method, and measured the magnetic characteristics of the cores as a function of the number of ribbons per group, the number of group per set. the air gap and radius of core edge.

• Journal of the Korean Magnetics Society
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• v.1 no.1
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• pp.37-41
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• 1991

A force sensor which employ the measurement of the change in the maximum induction of an amorphous core was constructed. This force sensor has a standard deviation of the non-linearity less than 0.1% within the range of 0 to 1 N, and a resolution of $1{\times}10^{-4}N$ for the core cross section of $6{\times}10^{-8}/m^{2}$. The sensor can also measure transient force at a sampling rate of 10 kHz which is the same as the magnetizing frequency of the core.

• Journal of Magnetics
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• v.15 no.4
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• pp.190-193
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• 2010

The design of joints in a transformer core significantly affects the transformer's efficiency. Air gaps cause variations in the flux distribution at the joints of the laminations, which depend on the geometry. Two similar samples consisting of electrical steel strips and amorphous ribbons were made. The spatial flux distributions were determined using an array of search coils for each sample. 2D models of these samples were created and examined by finite element analysis. The magnetic flux distribution for each lamination in the samples was computed. The results show that the flux density in amorphous ribbons above and below the air gap starts to approach saturation at lower flux density levels than for electrical steel. The flux density measured using the search coil under the air gap is increased in amorphous ribbons and decreased in the electrical steel with increasing frequency.

• 보일러설비
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• s.72
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• pp.97-98
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• 2000

• Proceedings of the Korean Magnestics Society Conference
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• 2001.04a
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• pp.92-93
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• 2001

• JOURNAL OF ELECTRICAL WORLD
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• no.8 s.164
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• pp.32-36
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• 1990

• JOURNAL OF ELECTRICAL WORLD
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• no.9 s.165
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• pp.38-42
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• 1990

• Journal of the Korean Magnetics Society
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• v.17 no.6
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• pp.226-231
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• 2007

High frequency loss property of nanocrystalline amorphous ribbon with a high resistivity insulation layer of $TiO_2$ and $SiO_2$ was studied. The insulation layer was fabricated by sol-gel method using dip-coating. The optimum composition ratio of metal alkoxide and slurry for fabrication of insulation layer was established and insulation layer with high adhesion was coated on the nanocrystalline amorphous ribbon. Frequency loss of magnetic core material manufactured on nanocrystalline amorphous ribbon with the surface insulation layer decreased over 40 % compared with that of magnetic core material without surface insulation layer. The insertion loss of an inductive coupler, which was prepared by using magnetic core material coated insulation layer, decreased due to reduction of frequency loss for magnetic core material and insertion loss decreased in proportion to frequency.