• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.10
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• pp.950-955
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• 2005

For the insulation design of a high temperature superconducting(HTS) cable, three kinds of design method were proposed, which used AC and impulse withstand voltage and partial discharge inception strength. However, the designed insulation thickness by AC and impulse could not be applied to cable fabrication process due to much low electrical breakdown strength. The effect of the multi-layered insulation paper was not considered on the previous insulation design and the insulation thickness by partial discharge inception strength could be applied only. In this paper, the electrical breakdown characteristic, which considered the effect of multi-layered of LPP, was investigated to design the insulation thickness.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.134-137
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• 1999

It is certain that the power quality will be very important at 21 century. Especially instant power shortage or power fault will occur serious problems. Accordingly stable power supplication is very technical problem. There are many way to make stable supplication as auxiliary generator, but this is long time delay complement. To solve this problem the superconducting magnetic energy storage is introduced. High Tc superconductor is more commercial.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.429-434
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• 1996

소각 또는 고온용융 등의 열처리 설비의 운전시 이로부터 예상되는 작업자 및 인근주민의 방사선 피폭을 보수적인 개념과 단순화시킨 피폭예측 식을 이용하여 산출해 보았다. 200kg/hr 용량의 소각로에 대해 발전소의 가연성 폐기물을 소각하는 경우 작업자의 피폭이 인근주민보다 훨씬 우려해야 하는 영향인자였으며 소각대상물 중의 핵종농도의 제한, 소각재 취급시 차폐의 증대 등이 요구된다. 따라서 작업자의 최대 피폭허용기준치를 기초로 폐기물내 핵종의 최대 허용 비방사능치를 계산해 보았고 각 핵종의 영향도를 제시해 보았다. 적용된 식은 각종처리 및 처분시설의 설계 및 운전전에 안전성 평가에 활용될 수 있으리라고 기대된다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.10a
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• pp.16-16
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• 1998

우주발사체용 로켓트 구조재로 사용되는 알루미늄합금 단조재는 강도확보를 위하여 고온으로 가열후 급냉과정에서 상당한 크기의 잔류응력이 발생되고 이로 인해 기계가공시 변형이 유발되어 조립성이 나빠진다. 잔류응력은 그 크기가 재료의 항복강도를 초과할 때 제거되므로 응력제거(stress relief)를 위해서는 외부하중이 가해져야 한다. 응력제거 처리는 소성변형, 열처리 및 초음파 등의 방법으로 수행되며 소성변형에 의한 제거효과가 가장 크다 형상이 복잡한 형 단조재의 경우 열간단조금형과 동일한 금형을 이용하는 TX52 등의 방법을 적용한다고 알려져 있으나 TX54에 대한 금형설계 및 소성변형률 적용 데이터는 공정 know-how로 분류되어 있다. 잔류응력제거 처리의 해석적 연구로는 판재와 링롤재에 대해서는 인장 및 압축 소성변형에 적용에 대한 결과가 발표된 바 있으나 형 단조재의 경우에는 전무하다

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.40-45
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• 2008

This study describes tensile test results under room and elevated temperatures for AISI 304 stainless steel which is widely used for a airframe structural material. Tensile tests were conducted according to ASTM standards. Reliability analysis was conducted by using normal probability paper to evaluate A and B basis tensile strengths applicable to airframe structural design.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2001.02a
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• pp.57-60
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• 2001

In this paper, a design scheme of SMES coil with HTS wire(BSCCO 2223) for least stray field and conductor consumption is presented. Three types of coils (solenoid, multiple solenoid, and modular toroid) have been considered. Shape and size of the coil was decided by line element method with evolution strategy and confirmed with Finite Element Method. Modular toroid displayed least stray field with given conductor length. The goal of the study is to establish designing technology of a HTS coil for SMES which works in relatively high magnetic field.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2001.02a
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• pp.84-88
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• 2001

The optimum cross-sectional area Profile of gas-cooled high-temperature superconductor (HTS) current lead is analyzed to have minimum helium boil-off rate. The conventional constant area HTS lead has much higher helium consumption than the optimum HTS lead considered in this study. The optimum HTS lead has variable cross-sectional area to have constant safety factor. An analytical formula of optimum shape of lead and temperature profile are obtained. For multi-step HTS current leads, the optimum tape lengths and minimum heat dissipation rate are also formulated. The developed formulations are applied to the Bi-2223 material, and the differences between constant area, constant safety-factor, and multi-step current leads are discussed.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2001.02a
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• pp.98-101
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• 2001

This work presents racetrack High Temperature Superconducting (HTS) magnet with iron plates to achieve the maximum current-carrying capacity and the simple shape that can easily be wound and jointed. The shape, position and kinds of iron plates are chosen by using 3 Dimensional Finite Element Analysis (3d FEA) considering magnetic saturation of iron plates. The racetrack HTS magnet with iron plates, magnet having optimized current distribution and initial magnet are compared with each other through 3D FEA, manufacturing and testing these magnets. The measured performance of the magnet with iron plates improved by 50% on the basis of initial magnet.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 1999.02a
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• pp.129-133
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• 1999

In recent years, there is a growing needs for large capacity underground power transmission lines with the increasing demand of electric power in the urban area, where various environmental limitations are imposed on the overhead transmission lines. But it is difficult to get the space for the underground power transmission cables because of complicated distributions of underground public facilties such as subway, water pipes, gas etc. As the superconducting power cables have the large power transmission capacity, the high power transmission capacity, the high power transmission density, and low loss characteristics in comparison with a conventional cable, it would be a solution to meet the increased power demand. In this paper, the results of the conceptual design and analysis of power system of HTS power transmission cable is described.

• Progress in Superconductivity and Cryogenics
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• v.13 no.3
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• pp.10-13
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• 2011

The power demand is steadily increasing due to rapidly develop of industrial field. The ratio of prospected increment of power consumption is over 2.2 % per year from 2007 to 2020 year. The superconducting fault current limiters(SFCLs) should be suggested to be one of promising machines to protect power grid. Four basis tests such as resistivity, short-circuit tests, ac losses and recovery time were investigated according to various reached maximum temperature, operating temperature. This paper deals with investigation of the various commercial high temperature superconductor for applying resistive type SFCLs.