• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.27-30
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• 2003

Recently, on power system, it is used to high voltage of transmission and distribution due to safe power supply and have high quality and insulation in order to satisfy excellent insulator. Thus, according to underground of high voltage cable, is occurred break down by ground short. Therefore, it is used to high quality XLPE power cable to interrupt instantaneous voltage drop. If it appear inner defect for cable whose have high quality and insulation, it is reduced rapidly due to concentration of electrical field. After assemble to manufacture, in order to inspect cable condition, it is decided much inspection standard. In this paper, In inner defect of assembling cable at manufacture, for measure the variation of insulation condition by void. it tested the variation of insulating characteristics, using $\phi$-q-n distribution variation in partial discharge experiment.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.187-189
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• 1997

Thermal and electrical breakdown phenomena in XLPE insulator of power cable were investigated. At high temperature the polymeric insulator was thermally deteriorated. Under the magnified high electric field, electrical tree was initiated at the sharp tip of needle electrode which was inserted to simulate the defects and impurities such as void, crack, metallic particles, dusts, and so on.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.465-470
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• 2008

This paper introduces experimental investigates of an electrical accident of the distributing cable termination with simulated badness construction. We prepared two termination kites, one is built-up type, the other is heat contraction type. Also, we manufactured cable termination that have simulated defect by badness construction and measured their insulation characteristics such as ac (35kV, 1min) and impulse (95kV, $1.2{\times}50{\mu}s$) withstand test. The influence of defects such as thickness and the gap between stress-con of housing and semi-conductor on insulating properties of the termination have been studied. The thickness decrease of insulator decreases ac breakdown strength. Dielectric breakdown traces of insulator that is damaged by knife displayed other shape. The gap of between housing and semiconductor deteriorates dielectric strength of insulator seriously.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1385_1386
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• 2009

In this paper, we examined the faulted cable joint through the external form analysis, material analysis, experimental verification and it's cause diagnosis system. It was not observed the voild, sharp material from the external form analysis and material variation. From the experimental verification, the thickness decrease of an insulator decreased ac breakdown strength suddenly and the breakdown traces of the insulator that was damaged by knife displayed elliptic shape. Thus, the faulted cable is assumed to accident that become dielectric breakdown by the deterioration of insulation performance that can happen when work.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.11
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• pp.514-519
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• 2006

To improve the mean-life and the reliability of power cable, we have investigated specific heat (Cp) and thermal conductivity of XLPE insulator and semiconducting materials in 154[kV] underground power transmission cable. Specimens were made of sheet form with the seven of specimens for measurement. Specific heat (Cp) and thermal conductivity were measured by DSC (Differential Scanning Calorimetry) and Nano Flash Diffusivity. Specific-heat measurement temperature ranges of XLPE insulator were from $20[^{\circ}C]\;to\;90[^{\circ}C]$, and the heating rate was $1[^{\circ}C/min]$. And the measurement temperatures of thermal conductivity were $25[^{\circ}C],\;55[^{\circ}C]\;and\;90[^{\circ}C]$. In case of semiconducting materials, the measurement temperature ranges of specific heat were from $20[^{\circ}C]\;to\;60[^{\circ}C]$, and the heating rate was $1[^{\circ}C/min]$. And the measurement temperatures of thermal conductivity were $25[^{\circ}C]\;and\;55[^{\circ}]C$. From these experimental results both specific heat and thermal conductivity were increased by heating rate because volume of materials was expanded according to rise in temperature. We could know that a small amount of CNT has a excellent thermal properties.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.1
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• pp.6-10
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• 2006

To improve mean-life and reliability of power cable, we have investigated specific heat (Cp) and thermal conductivity of XLPE insulator and semiconducting materials in 154(kV) underground power transmission cable. Specimens were respectively made of sheet form with EVA, EEA and EBA added $30[wt\%],$ carbon black, and the other was made of sheet form by cutting XLPE insulator in 154(kV) power cable. Specific heat (Cp) and thermal conductivity were measured by DSC (Differential Scanning Calorimetry) and Nano Flash Diffusivity. Specific-heat measurement temperature ranges of XLPE insulator were from $20[^{\circ}C]\;to\;90[^{\circ}C],$ and the heating rate was $1[^{\circ}C/mon].$ And the measurement temperatures of thermal conductivity were $25[^{\circ}C],\;55[^{\circ}C]\;and\;90[^{\circ}C].$ In case of semiconducting materials, the measurement temperature ranges of specific heat were from $20[^{\circ}C]\;to\;60[^{\circ}C],$ and the heating rate was $1[^{\circ}C/mon].$ And the measurement temperatures of thermal conductivity were $25[^{\circ}C],\;55[^{\circ}C].$ In addition we measured matrix of semiconducting materials to show formation and growth of carbon black in base resins through the SEM. From these experimental results, both specific heat and thermal conductivity were increased by heating rate because volume of materials was expanded according to rise in temperature.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.2
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• pp.190-195
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• 2009

This paper introduces experimental investigates of an electrical accident of the distributing cable termination with simulated a shoddy construction. We prepared two termination kites, one is built-in type, the other is heat contraction type. Also, we manufactured cable termination that have simulated defect by badness construction and investigated their insulation characteristics such as ac (35[kV], 1[min]) and impulse (95[kV], $1.2{\times}50[{\mu}s]$) withstand test. The influence of defects such as thickness decrease, the gap between stress-con of housing and semiconductor and heating time on insulating properties of the termination have been studied. The thickness decrease of an insulator decreases ac breakdown strength suddenly and the breakdown traces of the insulator that is damaged by knife displayed elliptic shape. The gap of between stress-con and semiconductor deteriorates dielectric strength of insulator seriously. In heat contraction type, the ac breakdown voltage became low when the heating time is short.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.495-498
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• 2001

The distribution line through which electricity is supplied from substation to customer generally varies by underground line and overhead line. In contrast that the underground line is shielded, the overhead lines do not have the shield layer. To overcome this weak point of the overhead lines, the aerial bundled cable(ABC) connection systems have been developed. The basic concept of the ABC connection system is the application of the underground cable system containing complete shield layer to the overhead cable system. The ABC system is the innovative technologies which enable the prevention of electric shocks, reduction of the maintenance charge and damage of the cable. This paper give a full detail of vertical connection system applied within a country.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.547-549
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• 2000

Silicone insulators have many advantages over porcelain insulators. Especially silicone insulators have good characteristics of impact hardness, surface insulation, ease of processing, mass productivity and don't have risk of bombardment and vandalism. Recently insulation part made by silicone are becoming widely used. In this paper we introduce the development of Sealing End for 132kV XLPE cable with silicone composite hollow insulator and the adoption of it to a actual transmission line in abroad. This paper contains of design procedure, structure, electrical performance of it.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.623-624
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• 2007

This work examines the effects of swelling MI type HVDC cable oil on the semiconductive silicone rubber and silicone rubber as used in accessories for application on outdoor termination (EBA) slip on sleeve. The behavior of volume resistivity is monitored as a function of the amount of cable oil diffused into the material. Resistivities of semiconductive silicone samples up to the typical insulator range (${\sim}10^{10}{\Omega}-cm$) are observed as a consequence of swelling due to the presence of the diffused oil. The measured volume resistivities of the oil-impregnated semiconductive silicone rubber are compared to desired value as function of stress relief cone.