• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1909-1911
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• 2000

Recently many research activities on the diagnosis of stator winding insulation of large rotating machines have been reported. Capacitive couplers are widely used as sensors for on-line partial discharge (PD) measurement of high voltage rotating machines. This paper presents laboratory test to compare Stator Slot Coupler (SSC), Resistance Temperature Detector (RTD), 80 [pF] coupler and 500 [pF] coupler for on-line PD measurement of rotating machines.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1930-1932
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• 2000

PD in defects of solid insulation system is very harmful since it leads to deteriorate insulation system by. the discharge electrons and ions bombarding the insulation surface and the action of chemical products that are formed by discharges. PD is used to detect and recognize defects and degradation of insulation system However, there are still marked difficulties to recognize defects by PD methode. In this paper, we investigated properties of PD of defects in solid insulation by using statical methods and classified PD patterns of surface discharge, electrical tree and void discharge with source of discharge, we used specific distributions such as $H_n(q)$, $H_{an}(\phi)$, $H_n(\phi)$, $H_a(\phi)$ to recognize defects of solid insulation system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.71-74
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• 2006

The introduction of materials and methods of construction which are appropriated to property of green roofs could be a decisive factor in a long-range durability and economical maintenance cost, moreover, it support to variety construction system and organization. In this paper I focused to assure the basic system for waterproofing materials and root barrier apply to green roof as searching the application of field condition. And I suggest proper waterproofing and root barrier as considering the mutual connection and plant growth. and it can be a standard model to adopt to domestic green roof system.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.354-356
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• 2003

본 논문에서 제시한 전력감시 시스템은 원주권광역상수도에 적용된 개방형 SCADA 시스템으로 무인화 사업장에 널리 사용되는 설비로서 중앙제어실에서 CRT화면을 통하여 원거리에 위치한 현장설비를 감시할 수 있으며 필요시 제어 명령을 보내서 해당기기를 제어하도록 구성되어 있다. 전기설비를 감시하는 모든 계전기는 디지탈로 구성되어 있어 전압, 전류값을 추적하고 판독하도록 되어 있다. 특히 각 판넬 내부에 설치된 폐쇄배전반 절연열화 진단설비는 전력설비 열화 시 발생하는 부분방전 검출을 위해 30MHz대역의 협대역으로 선정되어 있으며, 1초 동안 펄스 크기와 펄스 수량을 측정하여 열화진행과정을 실시간으로 근무자에게 통보하고, 또한 화재감시센서를 이용하여 화재발생 시 배전반 상부에 설치된 개별형 자동소화기가 동작하여 사고 파급을 막도록 구성하였다.

• 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.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.2000-2004
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• 2009

In general, for the condition monitoring of a power transformer using the UHF PD measuring technique, detection of any partial discharge, identifying the defect in the transformer and locating the insulation defect are necessary. In this paper one of the most frequent detects which can result in turn to turn fault in power transformer was examined for identifying the defect. In order to model the defect, as a discharge source, a partial discharge cell was used for experimental activity. Magnitude of electromagnetic wave signals and corresponding amount of apparent discharge were measured simultaneously against phase of applied voltage to the discharge cell. Frequency range and phase resolved partial discharge signals were measured and analyzed. The results will be contributed to build the defect database of power transformer and to decrease the occurrence of transformer faults.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.304-307
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• 2004

This paper simulated partial discharge caused by 22.9[kV] power cable using XLPE(Peroxide Crosslinkable Polyethylene) insulation having the outside damage. As one of the insulation diagnostic method a radiated electromagnetic waves were measured by an UHF method using a BiconiLog antenna(EMCO-3142) and a spectrum analyzer used to measure EMI, EMC. From results of this study, It was confirmed that discharge progress were possible to be estimated by the proposed method.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2066-2068
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• 2005

We developed an on-line Ultra-high frequency partial discharge monitoring system to prevent a catastrophic failure of gas- insulated switchgears. The system has been tested in the laboratory for detection of various UHF PD signals. We also performed detection sensitivity verification tests and compared them with conventional IEC60270 method.

• Proceedings of the KIEE Conference
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• 2004.05b
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• pp.125-127
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• 2004

We have developed the external-type PD sensors for detecting of the ultra high frequency (UHF) signals in various type of GIS. Sufficiently high sensitivity and accuracy for practical use were achieved for the PD sensor. The experience at the fields and the criteria for the judgment are also discussed in detail.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.9
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• pp.1189-1196
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• 2018

7 type composites (40, 45, 50, 55, 60, 65, and 70 wt.%)were prepared for the environmentally friendly GIS Spacer. Five kinds of samples were prepared for optimization of the filler content ratio (MS: MA = 1: 9, 3: 7, 5: 5, 7: 3, 9: 1) of epoxy / microsilica and microalumina. As a result of evaluation of the partial discharge resistance characteristic, surface erosion is generally slowed down as the fill amount of micro silica is increased. Also, partial discharge resistance characteristics for the development of insulating materials with optimal mixing ratios of heterologous showed a higher partial resistance of discharge and a decrease in erosion, as the filler content ratio of micro silica was larger. In the future, various researches such as electrical, mechanical, and thermal studies will be needed to develop insulating materials that can commercialize power devices in environmentally friendly insulating gas.