• Progress in Superconductivity and Cryogenics
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• v.9 no.1
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• pp.61-66
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• 2007

A transmission class high-temperature superconducting(HTS) power cable system is being developed in Korea. For insulation design of this cable the grading method of insulating paper is proposed. Two kinds of laminated polypropylene paper that has different thickness has been used as the electrical insulation material. The use of graded insulation gives improved mechanical bending properties of the cable. In a HTS cable technology the terminations are important components. A HTS cable termination is energized with the line-to-ground voltage between the coaxial center and outer surrounding conductors. in the axial direction. There is also a temperature difference from ambient to about 77 K. For insulation design of this termination, glass fiber reinforced plastic(GFRP) was used as the insulation material of the termination body, and the capacitance-graded method is proposed. This paper will report on the experimental investigations on impulse breakdown and surface flashover characteristics of the insulation materials for insulation design of a transmission class HTS power cable and termination. Based on these experimental data, the electrical insulation design of a transmission class HTS power cable and termination was carried out.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.2
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• pp.257-263
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• 2016

This paper describes the lightning arrester transients in cable head termination. The installation references of cable head tower and lightning arresters are firstly reviewed, then the performance of lightning arrester operation is also evaluated based on lightning overvoltage analysis by the change of grounding lead cable length. This paper finally proposes the optimal length of grounding lead cable at the cable head termination. The limited lightning current is also proposed according to the change of grounding lead cable length. The results will contribute to protecting insulation breakdown failure against lightning surge at the terminations and joints.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.160-162
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• 2003

Termination cryostat for 22.9kV, 1.26kA-class HTS power cable has been designed. The cryostat consists of vacuum vessel, liquid nitrogen vessel, current lead and HTS power cable. The current lead and the HTS power cable are connected in liquid nitrogen vessel cooled by forced-circulation subcooled liquid nitrogen. The maximum total heat load of this cryostat is expected to be 150w. In this paper, the detailed design of the termination cryostat is mentioned.

• Progress in Superconductivity and Cryogenics
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• v.5 no.1
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• pp.107-110
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• 2003

High Temperature Superconductor (HTS) transmission cable can carry more than 2 to 5 times higher electricity and also obtain substantially lower transmission losses than conventional cables. Liquid nitrogen is to be used to cool the HTS power cable and its cost is much cheaper than the liquid helium used for the cooling of metal superconducting wire. In Korea the HTS power cable development project has been ongoing since July, 2001 with the basic specifications of 22.9kV, 50MVA and told dielectric type as the first 3-year stage. The cryogenic system of the HTS cable is composed of HTS cable cryostat termination and refrigeration system. Termination of HTS cable is a connecting part between copper electrical cable at room temperature and HTS cable at liquid nitrogen temperature. In order to design the termination cryostat, it is required that the conduction heat leak and Joule heating on the current lead be reduced, the cryostat be insulated electrically and good vacuum insulation be maintained during long time operation. Heat loads calculations on the copper current lead have been performed by analytical and numerical method and the feasibility study fer the other candidate materials has also been executed.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1105-1107
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• 1999

The purpose of termination for high voltage tests of XLPE power cable is to prevent flashover during the breakdown test of specimen as well as to withstand the specified voltage between its conductor and screen without failure. For easier treatment and simpler construction of testing termination, resistivity grading method using semi-conductive material was employed. Based on the fundamental theory, its failure characteristics by changing the resistivity of semi-conductive material on the insulation surface was investigated. With two layers construction by difference resistivity on their surfaces, much improved result than that of one resistivity was obtained through the experiment for MV cable.

• Progress in Superconductivity and Cryogenics
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• v.13 no.3
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• pp.5-9
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• 2011

DC high-temperature superconducting(HTS) cable system has attracted a great deal of interest from the view point of low loss, dense structure and large capacity. A HTS cable system is made of cable and termination. The insulating materials and insulation technology must be solved for the long life, reliability and compact of cable system. In this paper, we will report on the dielectric breakdown characteristics of insulating materials for HTS cable and termination. The AC, DC and lightning impulse breakdown strength of laminated polypropylene paper(PPLP) and glass fiber reinforced plastic(GFRP) have been measured under nitrogen pressures in the range of 0.l-0.4MPa. PPLP and GFRP are found to have a significantly higher DC breakdown strength. Also, DC surface flashover voltage of negative polarity is slightly higher than that of positive polarity in GFRP.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.112-112
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• 2010

The purpose of development is to localize a connector for connection of cable and GIS for underground transmission system. The cable connector for GIS provides electrical insulation of GIS housing part and makes connection of ultra high voltage electrical apparatus and power cable by controlling electrical stress between electrodes of power cable termination. Generally Korean switchgear makers are using a connector for GIS made by foreign companies. We manufactured sample by best structure design of great capacity conductor connecting part and then modified the design by analysis of shape and section. We completed the suitable sample for current cycling test condition of conductor connecting part sample and ensured surge characteristics of line by short-time current test.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.93-93
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• 2010

We developed friction welded bimetallic sleeve for 220kV aluminum conductor XLPE cable. Not only friction welded bimetallic sleeve for Termination(EB-A, EB-G) but also friction welded sleeve for Joint of Al to Cu conductor was developed regardless of this project. Generally, friction welded sleeve used to connect Al conductor cable to Cu conductor cable and used for improvement of mechanical property of terminal by offer the copper side of friction welded bimetallic sleeve at the Termination. Connection method for Al-Cu conductor has mainly used friction welding at the solid state, because it is difficult to connect by using conventional welding method. this investigation introduces development of friction welded bimetallic sleeve by friction welding and test result of 220kV Al conductor XLPE cable and accessories using friction welded sleeve.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1299_1300
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• 2009

We show results that examine about electrical properties of XLPE insulated 6.6kV cable termination by mechanical damage. The cable used to produce the cable termination is 6/10kV tray XLPE fire retardant electric cable (6/10kV TFR-CV $35SQMM{\times}1C$) which is domestically made. We apply force to XLPE insulator and made mechanical defect using knife. Defected samples go through the withstand voltage test according to the IEEE std. 48 test regulations and lighting impulse (hereunder, IMP) withstand voltage test regulations. Then the effects of the scars shown during the construction process on electric accidents at the end part are analyzed.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1611-1613
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• 1998

The new type of prefabricated joint for 161kV XLPE cable have been developed. we, LG Cable & Machinery Ltd., made an huge contract with an foreign country's Power company for the supply of cable and accessories, the training of jointing and termination work to local personnel, technical assistance by joint venture and the supervision of installation and commissioning. By the end of 1997, one of several routes under the contract successfully finished being constructed and specially tested on site. In operation, now this underground transmission line proves well the reliability and efficiency of prefabricated joint and termination applied first time in foreign country.