• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.371-373
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• 2002

High current density Bi-2223 tapes have recently become commercially available. The ac loss is an important issue in the design of high-T$_{c}$ superconducting power cables. In such complicated devices, special caution is required in the placing of voltage leads for measuring the in-phase voltage. In this paper, the ac losses for different contacts and arrangements of voltage leads have been experimentally investigated in a single layer model cable and discussed.d.

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.89-89
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• 2004

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2000.02a
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• pp.55-57
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• 2000

In this paper we present the results of tests for the high-Tc superconducting (HTS) power cable core. A prototype HTS cable cores have been constructed using Bi-2223 based Ag-sheathed HTS tapes. HTS cable cores has been tested at 77K with DC currents. Results shows that the cable cores carrying up to 700A DC and self-field effects are discussed.

• 한국초전도학회:학술대회논문집
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• v.11
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• pp.72-72
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• 2001

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.210-212
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• 2003

High current density Bi-2223 tapes have recently become commercially available. The ac loss is an important issue in the design of high-T$_{c}$ superconducting power cables. In such complicated devices, special caution is required in the placing of voltage leads for measuring the in-phase voltage. In this paper, the ac losses for different contacts and arrangements of voltage leads have been experimentally investigated in a single layer model cable and discussed.d.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.900-902
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• 2003

Critical current($I_c$) degradation of HTS tapes after bending is one of the holiest issues in HTS development and application studies. Many people are measuring $I_c$ degradations for effect of tending radius. However even if the bending radius is larger than the breaking radius a HTS tapes can be damaged by repetitive bending, which is unavoidable in the winding processes. Therefore, We studied the $I_c$ degradation after repetitive bending, at 77K with self-field, of Bi-2223 tapes processed by "Powder-in-Tube" technique, which was made by America Superconductor Corporation(AMSC), Innova Superconductor Technology(InnoST) and Korea Electro-technology Research Institute(KERI). For each specimen $I_c$ degradation was measured various bending radius as function of repetitive bending number.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.280-284
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• 2000

The prototype high-T$_c$ superconducting (HTS) power transmission cables have been designed and fabricated multi layers of spirally wound HTS tapes. The cables were made Bi-2223 based Ag-sheathed HTS tapes, and tested in LN$_2$. Critical currents of 700A dc and better were achieved. The magnetic flux density and field direction were analyzed in the cable configuration. In this paper the results of analysis and tests of HTS power transmission cables were described.

• Progress in Superconductivity and Cryogenics
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• v.19 no.3
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• pp.1-7
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• 2017

It is required to reduce the cost of superconducting cable to realize a superconducting DC power network that covers a wide area in order to utilize renewable energy. In this paper a new concept of innovative cable is introduced that can enhance the current-carrying capacity even though the same superconducting tape is used. Such a cable can be realized by designing an optimal winding structure in such a way that the angle between the tape and magnetic field becomes small. This idea was confirmed by preliminary experiments for a single layer model cable made of Bi-2223 tapes and REBCO coated conductors. Experiments of three and four layer cables of practical sizes were also done and it was found that the current-carrying capacity increased as theoretically predicted. If the critical current properties of commercial superconducting tapes are further improved in a parallel magnetic field, the enhancement will become pronounced and this technology will surely contribute to realization of superconducting DC power network.

• Progress in Superconductivity and Cryogenics
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• v.2 no.2
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• pp.6-10
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• 2000

1.5 kA class HTS current leads for a SMES magnet, which are connected to a conventional vapor cooled copper leads, were designed. The HTS leads are composed of Bi-2223/Ag-Au tapes and a stainless stell tube. The estimated critical current of the lead is about 1.6 kA at 77.3 K and in a self magnetic field, and the heat input to the liquid helium from the cold end of the 35 cm lead is 0.4 W/lead. It has been made clear that the heat input decreases with increase of the lead length and decrease of the warm end temperature and Ag-Au/SC ratio.

• Progress in Superconductivity
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• v.1 no.1
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• pp.68-72
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• 1999

Since the discovery of high Tc superconductors, great efforts have been focused to develop high performance HTS magnets for the ultimate applications to power system devices. Magnet designers, however, have had difficulties in the estimation of the maximum operating current of the designed magnet from the tested short sample data, due to the degradation of the critical current density in the magnet. Similar story applies to the HTS electrical bus bar. It has been found that the critical current of Bi-2223 stacked tapes is much less than the total summation of critical currents of each tape, which is mainly attributed to the self magnetic fields. Furthermore, since the critical current degradation of Bi-2223 tape is greater in the normal magnetic field (to the tape surface) than in the parallel one, detailed magnetic field configurations are required to reduce the self field effects. In this paper, we calculate the self field effects of a stacked conductor, defining self field factors of normal and parallel magnetic fields to the tape surface. Finally, the critical current degradations in the HTS magnet are explained by the introduced self field factors of the stacked conductor.