• 대한전기학회논문지
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• 제39권6호
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• pp.568-576
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• 1990

Recently, streaming electrification in forced oil cooled power transformer has been taken up as a serious problem. In this paper, the charging tendency of various insulation oils, such as mineral oil, polybutene and silicone oil has been measured by means of an injection type charging tendency measuring apparatus under various condition. The experimental data of the dependence of the leakage current on flow velocity and temperature of oil can be explained by considering the flow state such as laminar and turbulent flow. The effect of additives on the charging tendency of mineral oil has been investigated. BTA is regarded as the most effective retardant to electrification of oil among the additives chose for this investigation.

• 한국전기전자재료학회논문지
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• 제11권2호
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• pp.162-166
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• 1998

Synthetic fluid, class 7 group 2, as an insulating and cooling material is selected as. specimen, arid it is studied for the physical and electrical properties. Also, Benzotriazole(following as BT A) known as a suppressant of streaming electrification is added to it, and the change of physical and electrical properties by addition of BT A is investigated. From the spectrum of FT-IR, it is confirmed that the absorption peak in wavenumbers $3400{\sim}3450[cm^{-1}]$ is small or disappears when BTA is added. AC breakdown strength and volume resistivity of each specimen are investigated. It is considered that the effective content of BTA is about 10[ppm] for the suppression of electrification in this experiment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1848-1850
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• 1996

A Couette Charger was used to simulate streaming electrification process in transformer. This paper describes the electrification characteristics of the energized and unenergized Couette Charger. By applying low frequency and high voltage across the cylinder of the Couette Charger, the measured short circuit current$i_{sc}$) is compared with the measured values of unenergized Couette Charger. As a result, short circuit current was increased with voltage.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.203-206
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• 1998

In this paper, specimens stirred with the several kinds of benzotriazole(following as BTA) addition which is very effective to decrease the streaming electrification, are tested to investigate the change of properties for insulating fluid using in ultra-high voltage transformer, and it will give a guideline to find out a proper quantity of BTA addition for the most effective suppression against the streaming electrification. In GC, we could not find out the change of the physical properties in an insulating fluid by BTA. In a flowing transformer oil, the characteristics on dielectric of specimen contained BTA 10[ppm] are superior to the others.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
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• pp.123-126
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• 2001

This study presents the simulation of the traction return current based on 2${\times}$25kV power supply system in order to determine the impedance bond intensity of impulse type track circuit on the Kyoungbo electrification line. The results of simulation enables us to measure the precise intensity of catenary current, returning to the substation through KTX (Korean Train Express) operated by 2${\times}$25kV power supply system with common earth network. In the wake of establishing 2${\times}$25kV and common earth network used in Korea for the first time, in particular, it is possible to determine the impedance bond intensity of impulse type track circuit, which is applicable to the Kyoungbo electrification line by specifying the relations among the traction return current, earth current, and catenary current.

• 한국안전학회지
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• 제8권2호
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• pp.10-15
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• 1993

In this paper, it is studied the electrostatic discharge In Insulating oil for the purpose of the technical control of the streaming electrification resulted from the interface between an insulating liquid and a solid. The streaming current increases exponentially with flow rate and In region of lower than 50［$^{\circ}C$］but decreases at higher than the same temperature. The phenomena of electrostatic discharge appear at an interface between measuring tank and insulating oil when the seven sheets of gauzes are inserted in electrification apparatus. And those of partial or surface discharge are shown when eight sheets are inserted.

• Corrosion Science and Technology
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• 제18권4호
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• pp.117-120
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• 2019

Considering the tendency of development of electrification vehicles, development and verification of new evaluation technology is needed because of new technology applications. Recently, as the battery package is set outdoors of an electric vehicle, such vehicles are exposed to corrosive environments. Among major components connected to the battery package, rust prevention of high-voltage cables and connectors is considered the most important issue. For example, if corrosion of high voltage cable connectors occurs, the corrosion durability assessment of using an electric vehicle will be different from general environmental corrosion phenomena. The purpose of this study is to investigate the corrosion mechanism of high voltage cable connectors of an electric vehicle under various driving environments (road surface vibration, corrosion environment, current conduction by stray current, etc.) and develop an optimal rust prevention solution. To improve our parts test method, we have proposed a realistic test method to reproduce actual electric vehicle corrosion issues based on the principle test.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1143-1145
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• 1995

In this paper, we measured leakage current that produced by static electrification at pressboard and insulating paper. We found that the leakage current increased as temperature increased, as oil velocity increased. The leakage current at pressboard is higher than that of insulating paper.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1292-1296
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• 2004

This study is experimented results of running characteristics about electric locomotive. it executed to study a power quality in the substation of Honam electrification line and to promote knowledge, observation and management in electric rail-system. we measured to know the more exactly running characteristics that electric locomotive and electric substation at the same time.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.516-521
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• 2002

This paper was reviewed technical items of catenary system for electrification of Gyeongbu(Dongdaegu∼Busan) and Honam(Daejeon∼Mokpo) conventional Railways. The lines have adopted new technical items in order to connect to Gyeongbu high speed railway. We can use the technology and experience of Gyeongbu and Honam lines to a new catenary system design up-graded for speed-up of conventional lines and new lines construction.