• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.1933-1937
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• 2008

XLPE insulated power cables are introduced in Korea in 1980s. The cable installation test has been carried out according to the Korean Technical Reference of Electrical Facilities. But recent research results shows DC Hipot test cannot detect the serious defects in XLPE insulated cables. VLF test is recommended as a installation test of XLPE insulated cables by CENELEC and IEEE standards in 1996 and 2001 respectively. We suggest to apply VLF test as an installation test for XLPE insulated MV cables in Korea.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1727-1729
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• 2002

To cope with increasing of electric power demand in metropolitan areas, large capacity underground power cables are needed. Under such situations, our company has developed 345kV XLPE insulated cable and accessories. As the final step of development of the 345kV XLPE cable and accessories, the pre-qualification test was carried out on the test line composed of cables, pre-fabricated joints, EB-Gs and EB-As. This paper sums up the pre-qualification test conditions and the results.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1460-1462
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• 2003

XLPE compound have used for insulation of 22.9 [kV] power cable. XLPE compound is aged for use long time in distribution line. The cause of aging is water tree is happening and growth. Accelerated water tree test method are Accelerated volatge method and high frequency method. In this paper, high frequency accelerated water tree was performed. And the result was analysed AC breakdown voltage and size and number of water trees.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05c
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• pp.53-57
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• 2002

Reduction of insulation thickness would be beneficial not only for increasing the cable length but would also improve its thermal performance. An interfacial diffusion method was devised to reduce insulation thickness by improving the interfacial properties of XLPE cable insulation. In this paper, to evaluate superficially the interface properties between XLPE insulation and semiconducting layer, the dielectric and insulation properties of tan${\delta}$ and volume resistance were measured with temperature dependence. Above the results, dielectirc and insulation properties with semiconductor/XLPE were more anormal than its bulk caused by the interfacial properties.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.441-444
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• 2000

In this paper, dielectric properties of XLPE sheets of 22kV cable with semiconducting and water were investigated. The breakdown strength of XLPE under rod/needle electrode were measured at without oil. It is found that the dielectric properties such tan$\delta$ of XLPE sheet dependence on semiconducting and water layer and are decreased much lower increase with temperature. The breakdown strength and the electrode effect are obtained as a function of thickness, and a equation for the sheet thickness dependent breakdown strength is also discussion.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1608-1610
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• 2000

In this work, the effect of annealing on physical and electrical properties of XLPE cable insulation was investigated. One sample was non-annealed and the other two samples were treated under air circulated oven at 80$^{\circ}C$ for five and ten days. In the DSC patterns of annealed specimen, new peaks appeared at near 80$^{\circ}C$ as a proof of thermal history. The degree of crystallinity increased by annealing effect. In the FT-IR spectrums, the change of absorbances to acetophenone and cumyl alcohol were observated according to the radial direction of cable insulation. They slowly diffused into both semi-conductive layer of the cable in proportion to annealing time and lastly led to near equilibrium state through cable insulation. The AC breakdown strength did not increased but the values were stabilized by effects of crystallinity and diffusion of by-products.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.5
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• pp.179-184
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• 2016

The usual way used by electric power stations to deliver high levels of generated power is via 6.6kV XLPE (or CV) cables. Depending on the manufacturing technique, installation environment, and usage conditions, the deterioration processes of the power cables start from the instant of operation. Cable junctions may break down in three years from the start of operation due to the manufacturing or construction defects. Otherwise they should be in good working order for 20-30 years. When the cable system (the cable itself and cable junctions combined) deteriorates, fire accidents happen due to the dielectric breakdowns. We have invented a device to monitor the deteriorating status of cables at Korean Western Power Co. Ltd. located in Taean, Chungcheongnam-do province. In this paper, we introduce the device hardware. Using the device, we have measured the insulation resistance and humidity in the sheath of the cables. We present, in analysed results, the effect of humidity on insulation resistance in cable sheaths.

• 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 Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.377-380
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• 2003

XLPE(Crosslinkable Polyethylene) 케이블은 절연성이 우수하여 전력용으로 많이 사용되고 있다. 그러나, 시설된지 오래된 케이블의 노후화와 지중 매설 케이블의 시공시 및 포설이후 외부손상 등으로 인해 정전사고가 많이 발생하고 있는 추세이다. 본 논문은 케이블의 외부 손상에 의해 발생하는 부분방전에 의해 공간으로 전파되는 전자파를 측정하는 UHF법을 통해 주파수 스펙트럼을 측정하고 측정된 데이터 처리를 통해 방전진전에 따른 스펙트럼의 특성을 분석하였다. $^{[1]}$[3][6]//

• Transactions on Electrical and Electronic Materials
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• v.7 no.5
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• pp.224-229
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• 2006

Many studies have been done on the application of residual charge measurement in cable degradation diagnosis. In this paper, the behavior of residual charges measured with water-tree degraded XLPE sheets and cable are discussed. At charge injection process, the charge is injected by applying dc voltage as a conventional method, suddenly cut-off ac voltage or impulse voltage. Therefore the residual charge is influenced by the applying process. At charge release process, transient dc current flows when applying ac high voltage and also ac high voltage superimposed to dc low voltage. From the results, new diagnosis method is suggested.