• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1213-1216
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• 1998

This paper presents the result of a feasibility study for the prediction method of fault symptoms on 22.9kV distribution line. In this paper, real distribution data was collected and analyzed to isolate failure signatures or parameters which were distinct behaviors before and after failure incident. A new strategy of analysis-based (event-date concept) prediction algorithm for the distribution insulators and a developed model system were also discussed.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1575-1577
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• 2000

345kV급 210KN 초고압 현수애자의 개발 시험 결과, 과전파괴하중시험에서 품질관리지수가 3.0 이상인 11.2였으며, 유중파괴전압시험에서는 기준치보다 40% 정도 높은 값을 보였다. 그리고 72kA$\cdot$ Cycle $\pm$10% 조건의 power arc시험에 파괴없이 만족하였으며, 경년변화시험 후의 확인시험에서도 품질관리지수가 11.47로 높게 나타났다. 애자련의 피로시험 및 진동피로시험 후의 하중확인시험에서도 기준치보다 10% 이상의 값을 보였다. 전체적인 시험조건에서 경년변화시험의 조건이 가장 가혹한 것으로 나타났다.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.363-365
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• 1999

800kV GIS(Gas Insulated Switchgear) was first developed by Hyosung Corporation in Korea at Dec. 1998 and is going to be installed first in the Dangjin Thermal Plant. We intoned to verify the structural safety of 800kV GIS under seismic load. The modal analysis of 800kV GIS has been carried out to obtain the natural frequency and mode shape. PATRAN was used for mode)ing exactly 800kV GIS Geometry. 800kV GIS FE(Finite Element) model was constructed of shell elements for the enclosures and beam elements for the conductors and the support insulators NASTRAN was used for analyzing the normal modes of 800kV GIS FE model.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.182-183
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• 2006

It has been studied about the important consideration in designing and construction of the reliability assessment facilities including the combined testing system for simulating condition of acceleratedly deteriorated environment, which enable to test and evaluate the large-sized HV power apparatus without any disassembly up to transmission class in this paper. Also it is described simply about its ratings and main technical specifications and trial running of the system. To evaluate the performance characteristics against combined test condition for various power installation, especially for the polymer type insulators and kinds of bushings, brief investigation and an analysis of test objects and related international codes and standards have been conducted.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.479-481
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• 2003

송전용 애자의 누설전류 측정을 위한 실증 시험장치로 애자의 누설전류 특성에 관한 조사를 하였다. 자기, 유리 및 폴리머 애자에 선간전압 154 [kV]의 전압을 인가하여 바닷가 주위에서 누설전류 파형과 일일 누설전류 및 외부 환경적 parameter들과의 상관 관계에 대하여 고찰하였다. 그 결과 자기 및 유리애자는 습기가 높은 새벽과 밤에는 높은 누설전류가 나왔으며 폴리머 애자는 hydrophobicity의 특성 때문에 환경적 변화에 크게 영향을 받지 않았다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.7-11
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• 2009

In this study, p-channel silicon-oxide-nitride-oxide-silicon(SONOS) transistors are fabricated and characterized as an unit cell for NAND flash memory. The SONOS transistors are fabricated by $0.13{\mu}m$ low power standard logic process technology. The thicknesses of gate insulators are 2.0 nm for the tunnel oxide, 1.4 nm for the nitride layer, and 4.9 nm for the blocking oxide. The fabricated SONOS transistors show low programming voltage and fast erase speed. However, the retention and endurance of the devices show poor characteristics.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1358-1363
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• 2004

The objective of this work is to propose calibration facility in which a thin film type heat flux sensor can be calibrated under convective flow condition by using a small wind tunnel with the constant temperature plate condition. A small wind tunnel has been built to produce a boundary layer shear flow above a constant temperature copper plate. 12-independent copper blocks, thin film heaters, insulators and temperature controllers were used to keep the temperature of flat plate constant at a specified temperature. Three commercial thin film-type heat flux sensors were tested. Convective calibrations of these gages were performed over the available heat flux range of $1.4{\sim}2.5kW/m^2$. The uncertainty in the heat flux measurements in the convective-type heat flux calibration facility was ${\pm}2.07%$. Non-dimensional sensitivity is proposed to compare the sensitivity calibrated by manufacturer and that of experiment conducted in this study.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.712-717
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• 2005

In this thesis, it is investigated that the effect of the cross linked polyethylene(XLPE) insulator do to breakdown phenomenon by the insertion of the needle and bar electrode into XLPE which is used of electric power cable for the ultra-high voltage. The result of the partial discharge properties in the specimen showed that in case of the insertion of needle or bar electrode into XLPE, the effect of the inner discharge become large when the air void is bigger then the clearance of the electrode of the specimen. The closer the distance between the insulator and needle electrode, it takes less time to the insulation breakdown.

• Polymer Science and Technology
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• v.2 no.3
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• pp.158-168
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• 1991

본고에서는 고분자절연체의 내부전하분포 측정을 위한 측정원리, 측정장치 및 실제측정예 등에 대하여 언급하였다. 이 방법은 고분자내에 존재하는 전하의 종류, 위치 및 전하량에 대한 정보를 얻을 수 있으므로 고분자의 절연성질을 이해하는데 도움을 줄 것으로 생각한다. 특히 폴리에틸렌의 경우 여러 가지 요인, 즉 수지의 종류 또는 첨가제의 유무 등에 의해 각기 다른 내부전하분포를 갖는다는 사실이 밝혀졌다. 이와 같은 사실은 고분자 내부에 존재하는 공간 전하 때문에 외부전압에 의한 전기장이 변형되고 이에 따라 고분자의 절연성질이 변형될 수 있다는 점을 생각할 때 매우 중요한 의미를 갖는다고 할 수 있다. 따라서 고분자의 절연성질에 대한 이해를 높이기 위하여는 절연성질과 내부전하분포와의 관계에 대한 보다 깊은 연구가 이루어져야 할 것으로 생각된다.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.5
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• pp.206-206
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• 2003

It is hard to expect excellent electrical, mechanical and chemical properties from most of the composite materials presently used as insulators due to insufficient wettability property caused by the difference of interfacial properties between the matrix material and the reinforcer. Therefore, various interfacial coupling agents have been developed to improve the interfacial properties of composite materials. But if the wettable coupling agents are used outdoor for a long time, change in quality takes place in the coupling agents themselves, bringing about deterioration of the properties of the composite materials. In this study, glass surface was treated by plasma to examine the effect of dry interface treatment without coupling agent. It was identified that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. Also, the surface resistance rate and dielectric property were improved.