• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.406-410
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• 1995

A superconducting cable is one of the promising methods of undground transmission of high electric power in the future. It is very important that composite insulation system of $LN_2$ and polymer films takes into consideration for application high $T_c$ superconductor. This study is about both the partial discharge and properties V-t in $LN_2$. As result, applied voltage doesn't depend on the radius of non-eroded area but eroded area. And eroded area is observed the formation such as the ring of a tree.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.22-23
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• 2015

As wireless power transfer (WPT) technology using strongly coupled electromagnetic resonators is a recently explored technique to realize the large power delivery and storage without any cable or wire, this technique is required for diffusion of electric vehicles (EVs) since it makes possible a convenient charging system. Typically, since the normal conducting coils are used as a transmitting coil in the CPT system, there is limited to deliver the large power promptly in the contactless EV charging system. From this reason, we proposed the combination CPT technology with HTS transmitting antenna, In this study, we examined the improvement of transmission efficiency and properties for HTS and copper antennas, respectively, at 30 cm distance. Thus, we obtained improved transfer efficiency with HTS antenna over 10% compared with copper antenna

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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• pp.86-88
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• 1999

We investigated the current limiting characteristics of resistive and inductive SFCLs with $100{\Omega}$ of quench impedance for a line-to-line fault in the 154 kV transmission system. The fault simulation at the phase angles $0^{\circ}$, $45^{\circ}$, and $90^{\circ}$ showed that the resistive SFCL limited the fault current less than 15 kA without any DC component after one half cycle from the instant of the fault. On the other hand, the inductive SFCL suppressed the current below 13 kA, but with $2{\sim}3\;kA$ of DC component which decreased to zero in 6 cycles. We concluded that the inductive SFCL had higher performance in current limiting but the resistive SFCL was better from the view point of DC components.

• Progress in Superconductivity
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• 제1권1호
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• pp.73-80
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• 1999

We investigated the current limiting characteristics of resistive and inductive SFCLs with 100 $\Omega$ of impedance for line-to-ground faults in the 154 kV transmission system. The fault simulation at the phase angles $0^{\circ}$, $^45{\circ}$, and $90^{\circ}$ showed that the resistive SFCL limits the fault current less than 17 kA without any DC component after one half cycle from the instant of the fault. On the other hand, the inductive SFCL suppresses the current below 14 kA, but with 5 kA of DC component which decreases to zero in 5 cycles. We concluded that the inductive SFCL has higher performance in current limiting effect, but the resistive SFCL was better from the viewpoint of less DC components.

• 한국초전도ㆍ저온공학회논문지
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• 제7권2호
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• pp.16-20
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• 2005

As power systems grow more complex and power demands increase, the fault current tends to gradually increase. In the near future, the fault current will exceed a circuit breaker rating for some substations, which is an especially important issue in the Seoul metropolitan area because of its highly meshed configuration. Currently, the Korean power system is regulated by changing the 154kV system configuration from a loop connection to a radial system, by splitting the bus where load balance can be achieved, and by upgrading the circuit breaker rating. A development project applying 154kV Superconducting Fault Current Limiter (SFCL) to 154kV transmission systems is proceeding with implementation slated for after 2010. In this paper, SFCL is applied to reduce the fault current in power systems according to two different application schemes and their technical impacts are evaluated. The results indicate that both application schemes can regulate the fault current under the rating of circuit breaker, however, applying SFCL to the bus-tie location is much more appropriate from an economic view point.

• Transactions on Electrical and Electronic Materials
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• 제6권6호
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• pp.289-293
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• 2005

We have fabricated superconductor ceramics by chemical process. A high Tc superconductor with a nominal composition of $Bi_2Sr_2Ca_2Cu_3O_y$ was prepared by the organic metal salts method. Experimental results suggest that the intermediate phase formed before the formation of the superconductor phase may be the most important factor. The relation between electromagnetic properties of Bi HTS and external applied magnetic field was studied. The electrical resistance of the superconductor was increased by the application of the external magnetic field. But the increase in the electrical resistance continues even after the removal of the magnetic field. The reason is as follows; the magnetic flux due to the external magnetic field penetrates through the superconductor and the penetrated magnetic flux is trapped after the removal of the magnetic flux.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.699-700
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• 2006

고온 초전도 전력케이블의 통전용량 산정은 먼저 고온 초전도 전력케이블의 임계전류를 먼저 알아야 한다. 선재의 임계전류를 알고자 하는 경우, 전압-전류를 측정하거나 온도를 측정하는 방법을 통해 임계전류를 알아내지만, 고온 초전도 전력케이블의 경우 이러한 방법으로 임계전류를 알아내는 것이 불가능하다. 본 논문에서는 고온 초전도 케이블에 사용되는 선재에 대한 임계전류를 측정하고, 전자장 해석을 한 후, 실험결과와 해석 결과를 토대로 고온 초전도 전력케이블의 임계전류를 계산하였다. 이렇게 계산된 임계전류를 이용하여 고온 초전도 전력케이블의 통전용량의 기초자료로 활용토록 하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.972-974
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• 1997

Design & Operation of power system for meeting increase of electric Power demand is becoming more difficult and complex. One of reasons is increase of fault current. As one of the most effective methods for suppressing the fault current installation of SFCL is expected. These paper describes a method of fault analyses of power system with SFCLs, and also discusses determination of specification of SFCLs, effects of limiting the fault current due to SFCLs by use of the model system of two - bus electric power system with single transmission lines.

• Journal of Magnetics
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• 제16권4호
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• pp.413-416
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• 2011

An array of FeCo nanotubes has been successfully fabricated in the pores of porous anodic aluminum oxide (AAO) templates by wetting templates method. The morphology and structure of the nanotube array were characterized by scanning electron microscopy, transmission electron microscopy and x-ray diffraction. The average diameter of the nanotubes was about 200 nm, and the length was more than 10 ${\mu}m$. Vibrating sample magnetometer and superconducting quantum interference device were used to investigate the magnetic properties of the nanotube array. Interaction between the nanotubes has been found to be demagnetizing as expected and the switching field distribution is broad.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.255-258
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• 1999

We investigated the current limiting characteristics of resistive and inductive SFCLs with 100 $\Omega$ of quench impedance for a single line-to-ground fault. which accounts for about 70% of the total power line faults, in the 154 kV transmission system. The fault simulation at the phase angles 0$^{\circ}$, 45$^{\circ}$, and 90$^{\circ}$ showed that the resistive SFCL limited the fault current less than 15 kA without any DC component after one half cycle from the instant of the fault. On the other hand, the inductive SFCL suppressed the current below 12 KA, but with 3 kA of DC component which decreased to zero in 5 cycles. We concluded that the inductive SFCL had higher performance in current limiting but the resistive SFCL was better from the view point of DC components.