• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2271-2273
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• 2005

The cyclic aging for 14days is performed in order to remove the large amount of the volatiles contained in freshly manufactured cable. And the accelerated water treeing test(AWTT) is performed to accelerate the occurance of the water tree in the dielectric of XLPE. In this paper, we examined the AC breakdown voltage characteristics of the 22.9kV power cable before and after the cyclic aging for 14days and the AWTT. As the result, the AC breakdown voltage of the TR CNCV-W power cable is higher than that of CNCV-W and FR CNCO-W power cable.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.267-270
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• 2002

It is very important to analyze the superconducting power cables by the modeling for correct and reasonable cable design suitable for the domestic situation of power systems. This paper describes the basic modeling for superconducting power cables using ATPDraw. And also it is shown the line constants of cold dielectric coaxial type which is one of the HTS cables. It is compared with the line constants of general two kinds of power cables(OF, XLPE).

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1031-1033
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• 1999

The performance of cable joints for extra high voltage XLPE cable system is rapidly advancing combined with the development of insulation materials. The current trend of joints is in the direction of requiring less jointing techniques and installation time. This paper describes the performance of currently used joints regarding to their practical aspects and analyses design and manufacturing techniques for Pre-Mold Joint and Pre-fabricated Joint Box. Especially, basic tests and their results to obtain the design Parameter of PMJ are introduced.

• Progress in Superconductivity and Cryogenics
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• v.12 no.1
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• pp.61-65
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• 2010

To develop the thermal analysis method for the thermal behavior of HTS power cable system, cooled with sub-cooled liquid nitrogen, new thermo dynamic model for HTS cable system is introduced. The introduced thermal model is mainly modified from the thermal circuit following to IEC60287 for underground power cable systems such as XLPE or paper wrapped insulation cables. The thermal circuits for HTS cables are similar to the forced cooled underground cable system but the major thermal parameters and the configuration is apparently different to the normal cable systems so there has been no proposals in this field of analysing method. In this paper, 154kV HTS cable system has been introduced as an aspects of thermal models and a thermal circuit is proposed for the fundamentals on the dynamic rating systems for the HTS cable system. By using the thermal circuit developed in this paper, the optimal controls on the sub-cooling system's capacity become possible and it is expected to make the efficiency of HTS cable higher than conventional static controls.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.162-163
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• 2006

XLPE is used to insulator for Ultra High Voltage power cable. It is easy to processing also has a good insulating property. The study for diagnosis of lifetime and improvement is proceeding continuously. In this paper, it is investigated partial discharge distribution according to slope of needle electrode 0, 20, $40^{\circ}$. Applied voltage is 0.5 [kV/s] by step form for inception voltage. As the result of study, we conformed that increase of slope led to reduce of discharge number and total discharge quantity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.86-89
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• 2004

To estimate a electrical performance of the extra high voltage XLPE cable the discharge properties due to shift of void position were investigated. The ${\phi}-q-n$ properties have been measured at room temperature by rising voltage ratio of 0.5[kV]. An obtained data was stored to personal computer through A/D converter. The period of applied wave form and discharge values were divided into 64 parts and discharge values generated during 10 seconds were accumulated by phases. As a result, it was confirmed that the charge, phase angle and counts of discharge changed due to void position.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.256-257
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• 2005

To estimate a electrical performance of the extra high voltage XLPE cable the discharge properties due to shift of void position were investigated. The $\Phi-q-n$ properties have been measured at room temperature by rising voltage ratio of 0.5[kV]. An obtained data was stored to personal computer through A/D converter. The period of applied wave form and discharge values were divided into 64 parts and discharge values generated during 10 seconds were accumulated by phases. As a result, it was confirmed that the charge, phase angle and counts of discharge changed due to void position.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1102-1104
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• 1999

It is very essential to find out defects and remove them in the insulation at the early stage because the defects in the insulation induce PD which deteriorates the material, resulting in the breakdown. In the real application of high voltage, the interface of the different insulation is the weakest place for both electrical and mechanical aspects. In this paper, characteristics of PD caused by the artificial defects, such as metallic particles, voids and moist fibers, at the interfaces of the cable joint (PJB) were investigated using the specially designed electrode system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.516-522
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• 2020

Water trees can cause considerable damage to the performance of underground cables. Theymay formwithin the dielectric used in buried or water-immersed high voltage cables. They grow in a bush-like or tree-like form, often taking decades before causing damage to a cable's performance. They are usually found on very old underground cables, often in an inaccessible place. It is costly and time-consuming to detect watertrees in underground cables. Tree detection technology, including mathematical modeling,can reduce the maintenance cost and time necessary for detecting these trees.To simulate detection of water trees in this study, a mathematical model ofan XLPE cable and a water tree were developed. The complex water tree structure was simplified, based on two identified patterns of aventedtree. A Matlab simulation was performed to calculate and analyze the capacitance and resistance of a cable insulation layer,based on growth of a watertree. Capacitance size increased about 0.025×10^-13[Farads/mm] compared to normal when the tree area of the cable was advanced to 95% of the insulation layer. The resistance value decreased by about 0.5×10¹⁶[ohm/m]. These changesand changesshowninaBurkes paper physical modeling simulation are similar.The value of mathematical modeling for detecting water trees and damage to underground cables has been demonstrated.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.3
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• pp.189-195
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• 2017

The only method used in the power stations in order to deliver generated electric power is 6 kV XLPE (or CV) single core cables. Among many kinds of accidents happening in the power stations, the outbreak of fire due to the deterioration of live cables causes enormous socioeconomic losses. From the installation of the cables, the management and diagnose should be thoroughly made. Even though it differs depending on the installations and usage conditions, the cross-sectional area of cables is in shortage. The excessive allowable temperature caused from the current causes the deterioration of cables. In order to prevent an unexpected breakdown of live cables, we have invented a device to monitor and diagnose the status of cables. We have installed our device in the Korea Western Power Co., Ltd.. In this paper, we present our research results in situ that we have obtained by measuring the temperature of sheath, changing with the surrounding circumstances, especially ambient temperatures. We also show our study results of characteristics for temperature of sheath surface and load current at the ambient temperatures of $40^{\circ}C-10^{\circ}C$.