• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.585-586
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• 2015

GIS(Gas Insulated Switchgear) 가스구획은 SF6 가스와 강화 에폭시로 만들어진 스페이서를 통해 절연 성능을 유지하고 있는데, 초기 설치 시 조립 오류로 인한 부유 물질이나 철 파편 등에 의한 절연 파괴 및 GIS의 장시간 운전에 따른 열화에 의한 절연 파괴로 아크 사고가 발생한다. 그러나 GIS는 가스로 밀폐된 타입이므로 열화 현상으로 생성되는 이물질 또는 균열에 의한 내부 절연 파괴 현상(내부 아크)을 정확히 알 수 없을 뿐 아니라 사고 위치를 확인하기 어렵다는 단점을 가지고 있다. 본 연구에서는 수동 광소자 방식을 이용하여 GIS 내부 아크발생 시 정확한 탐지 및 위치 표정이 가능하며, GIS 내부에서 발생되는 아크를 바로 제거하고 반복적인 아크가 발생되지 않도록 보호계전기에 의한 GIS의 재폐로 동작을 차단 할 수 있는 GIS 아크탐지 장치를 소개한다.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.289-292
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• 1990

This study is to develope a spacer having almost uniform field distribution along the profile by controlling the high electric field in tensification at earthed part, especially triple junction in the spacer-electrode-gas boundary interface. Based on the extensive field calculation using CSM, a model spacer has been manufactured and tested. The test results show that the breakdown strength of the spacer is almost same as that of SF6 gas itself without spacer.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.11
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• pp.556-562
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• 2001

Spacer is used between main tank and auxiliary tank for on load tap changer in gas insulated power transformer. This paper deals with electrical design of spacer and discusses different analysis method of between 2D FEM(finite element method) and 3D FEM. To design spacer, we modeled structure of two kind of coaxial cylinders of spacer conductors and analysised electric field of spacer at impulse and induced test voltage condition. Spacer has 13 conductors and electric field was changed according to arrangement of conductors. We could find out arrangement of conductors at which electric stress is minimum. And this arrangement was satisfied with actual test conditions.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.3
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• pp.24-33
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• 2015

Linerboards containing wood flours were developed to increase solid contents in wet pressing process. Presence of wood flours in recycled fibers allowed passage of pressurized water at high wet pressing pressure, and increased solid contents while keeping the bulk of the board. The amount of wood flour addition should be controlled based on the intensity of the wet pressing pressure and the properties of the wood flours. Addition of cationic starch to the wood flour containing OCC furnish showed synergic increase of solid content and strength properties. Shapes of the wood flours such as spherical and rod type added to OCC furnish affected largely their solid content, drainage, and board physical properties.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.540-542
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• 2000

This paper describes the particle-initiated breakdown characteristics of various spacers, which have a ribbed surface, in the presence of a metallic particle. The particle was attached on the surface of each spacer. The breakdown voltages were measured by changing the length and thickness of the rib. Also the electrical field analyses were performed. As a result, the breakdown voltage of the spacer with two ribs was highest, and it was varied by the length and the thickness of the rib. Especially, in case of the rib with round edge, the breakdown voltage was higher than that with rectangular edge, which complied with the result through the field analysis.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1921-1923
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• 2000

This paper describes the particle-initiated breakdown characteristics of various spacers, which have a ribbed surface, in the presence of a metallic particle. The particles was attached on the surface of each spacer. The breakdown voltages were measured by changing the particle position on the spacer, the length and thickness of the rib. Also the electrical field analyses were performed. As a result, the breakdown voltage of the spacer with two ribs was highest, and it was varied by the length and the thickness of the rib. Especially, in case of the rib with round edge the breakdown voltage was higher than that with rectangular edge, which complied with the result through the field analysis.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.180-181
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• 2006

In this paper, there have been brief review about the important consideration in laboratory planning and construction of the reliability assessment infrastructure including 400 kV, 120 kVA AC test system, which enable to evaluate the HV long-term overcharged withstand performance for spacers using in Gas Insulated Switchgears up to transmission class, Also it is described simply about its trial running of the whole test system and its assessment example. To inform the founded national code, RS C 0084, and the procedure for getting a reliability assessment certificate issued by the government, brief description of the code and summation of test results have been conducted.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.436-438
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• 2003

Wind-induced oscillations are known to cause damage to the conductors and related hardware through fatigue, clashing of the bundled conductors and bolt loosening. Wake-induced oscillations have been known since the advent of bundled conductors, they are caused by aerodynamically unstable forces acting on the leeward conductors in the wake of the windward conductors, They take the form of horizontal galloping, snaking or rolling, in which case all subconductors move together in unison. They can also take the form of the subspan oscillation, which appear as elliptical motions of the subconductors moving out of phase, mainly in the horizontal plane within a subspan. In order to decrease amplitudes of the oscillation, this paper examines the application status of the spacer dampers and suggests proper installation methods.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.11
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• pp.635-639
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• 2000

In this paper, a new idea about ultra-clean aligning and mounting method of FED spacers was introduced. The glass-to -glass electrostatic bonding process was employed in order to bond the micro-structures of spacers to black matrix area formed on an FED anode substrate. It is possible to get adhesive-free bonding interface and well-aligned spacer array on an FED anode substrate with a ${\pm}5{\mu}m$ accuracy. Finally, I inch-sized FED panel was demonstrated to make sure of its applicability to FED panel fabrication.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2220-2222
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• 2005

Epoxy Insualtion spacers for supporting the conductors and partitioning the sections in $SF_6$ Gas insulated Switchgear(GIS), require higher electrical, Thermal and mechanical reliability with other principal components in GIS to be operated without any failure in use. In this paper, we describe the results of the performance evaluation of electrical and mechanical properties for extra high-voltage GIS according to KEPCO spec. and the requirements of the insulators for GIS specified by IEC 62271-203(2004).