• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.313-316
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• 1995

In this study, in case the lead sheath of XLPE cable (radius : 15cm, inner conductor radius : 5cm, insulation paper raidius : 6cm, dc voltage : 1MV) is harmed, so that breakdown process by inhomogeneous eletric field is simulated with Finite Element Method. The result of simulation showed that defect of lead sheath layer caused breakdown.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1805-1807
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• 2004

This simulated partial discharge caused by 22.9[kV] power cable using XLPE(Peroxide Crosslinkable Polyethylene) insulation having the outside damage. Asone 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 EMl, 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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• 2015.07a
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• pp.1173-1174
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• 2015

내연 발전기(50 MW, 13.8 kV) 출력단자에서 차단기까지 연결된 13.8 kV XLPE(cross-linked polyethylene) 케이블에서 운전중에 절연파괴로 인해 지락이 발생하였다. XLPE 케이블의 건전성을 확인하기 위해 절연저항과 절연진단 시험을 수행하였다. 교류전압을 1~10 kV까지 증가하면서 XLPE 케이블의 유전정접 측정결과 A상과 C상은 0.1%로 일정하게 측정되었다. 반면에 B상의 유전정접은 1 kV에서 0.54%, 2 kV에서 0.68%, 3 kV에서 0.82%, 4 kV에서 1.12%로 증가하였다. 그리고 교류전압을 약 4.3 kV 인가 중에 진단장비가 차단되었다.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.722-730
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• 1994

The effects of antioxidant and carbon black on weatherability of crosslinked polythylene(XLPE) for electrical insulation were investigated. 16 compositions were prepared in other to determine the weathering resistance. Samples were exposed in xenon-arc lamp Weather-Ometer for 500, 1000, 1500, 2000 hours respectively. Tensile strength, elongation at break, dielectric strength and tan ${\delta}$ were measured to evaluate the weatherability of XLPE. The results indicated that the effect of carbon black was more prominent than antioxidant and synergistic effect, was observed when two additives were mixed.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2136-2138
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• 1999

In this study, we describe the change of electrical properties of XLPE with electrical-tree degradation. XLPE insulation was used as specimen which was cut off from 22.9kV XLPE insulated cable and made in a type of block. The applying voltages are 8kV, 10kV, 12kV and frequency is 60Hz Ogra needles having tip radius of 10$\mu\textrm{m}$ were inserted in blocks. PD quantity and $tan{\delta}$ and DC current were measured from inception of tree to breakdown and their characteristics were analyzed.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1652-1654
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• 1994

The Extra-high voltage XLPE cable is characterized by low transmission loss, large capacity, and high reliability. Conventionally, for XLPE cables of l54kV and above, aluminium sheath was used to be moisture barrier (thus preventing water tree deterioration of the insulation) and to protect cable core from physical stresses. However, as transmission capacity of the cable increases, so does the cable diameter and the corresponding aluminium sheath outer diameter and thickness. As a result, eddy-current loss in the sheath is increased, limiting the maximum current capacity of the cable itself. As an alternative to aluminium sheath, we have adopted stainless steel sheath with non-magnetic properties and a large resistivity, The new XLPE cable with stainless-steel sheath (CSZV cable) has drastically reduced eddy-current loss in the sheath.

• Composites Research
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• v.35 no.3
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• pp.127-133
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• 2022

Polypropylene (PP) has been received great attention as a next-generation high-voltage power cable insulation material that can replace cross-linked polyethylene (XLPE). However, the PP cannot be used alone as an insulation material because of its high elastic modulus and vulnerability to impact, and thus is mainly utilized as a form of a copolymer with rubber phases included in the polymerization step. In this paper, a soft PP-based blend was prepared through melt-mixing of impact PP, polyolefin elastomer, and propylene-ethylene random copolymer. The elastic modulus and impact strength of the blend could properly be decreased or increased, respectively, by introducing elastomeric phases. Furthermore, the blends showed a high storage modulus even at a temperature of 100℃ or higher at which the XLPE loses its mechanical properties. In addition, the blend was found to be effective in suppressing the space charge compared to the pristine PP as well as XLPE.

• KEPCO Journal on Electric Power and Energy
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• v.8 no.2
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• pp.73-77
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• 2022

Recently, as the number of years of operation has increased for more than 30 years, interest in evaluating the remaining life of major power facilities such as transformers and ultra-high voltage cables is increasing. In particular, the risk of failure is increasing because the underground transmission XLPE cable has been built since 1980 and has been operating in excess of 30 years of design life or close proximity. Therefore, it is necessary to develop an algorithm to evaluate the residual life of the XLPE cable considering the load to determine the risk of failure. Since load data is large amount of data, it is necessary to make the variable load information equivalent to the time unit first in order to calculate the remaining life of the system quickly. In overseas literature, transformers are reported to be standardized for variable load equivalent conversion formulas, but they have not been reported for ultra-high voltage cables. Therefore, in this paper, whether the equivalent conversion formula of a transformer can be applied to XLPE cables was reviewed through accelerated degradation tests under equivalent and variable temperature conditions, and considerations were studied when evaluating the remaining operating life of XLPE cables based on the experimental results.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.274-276
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• 1991

Since the successful development of 154kV XLPE cable in 1983, its commercial use has been drastically expanded due to technical advantages and high performance of insulation, Futhermore, the large conductor size of 1200ml and 2000ml has been mainly employed in Korea for the purpose of meeting the bulk power demand in urban area. However, it is highly required to solve the problems which can be occured at the level of the joints between the cables of different type such as between existing OF and XLPE cables.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1519-1520
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• 2011

XLPE는 절연성 및 기계적, 열적 특성이 양호하여 1980년대부터 지중배선용 전력케이블의 절연재료로 사용되었다. 현재는 원재료의 성능 개선과 제조기술의 향상에 힘입어 초고압 교류 송배전 케이블용 절연재료로 적용 되고 있다. 절연파괴 강도에 대한 검토는 송전용량의 증대 및 초고압화가 가속됨에 따라 고전계하에서의 장기적인 절연성능을 좌우하는 중요한 요소이며, 절연 열화 현상을 진단하는 방법으로도 이용되고 있다. 본 연구에서는 HVDC용 나노복합 XLPE의 절연재료 평가기술 개발의 기초연구로써 최적의 나노 복합 재료를 확인하기 위하여 제작된 시편들의 전기적 특성 및 열적 특성을 평가하고자 한다.