• Title/Summary/Keyword: UHV

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Research on report equipments application status for live-line works in UHV T/L (초고압 송전선로용 활선장비 활용현황 조사연구)

  • Lee, Hyeong-Gwon;Sohn, Heung-Gwan;Kim, Hyo-Jin;Kim, Dae-Sik
    • Proceedings of the KIEE Conference
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    • 2003.07e
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    • pp.127-131
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    • 2003
  • We have investigated about kinds of the equipment according to use. They have many kinds of equipments, namely conductive cloths, insulated gloves, conductive shoes, insulated sticks, swivel boom, fittings and insulator cradles etc. We have suggested about use of equipments, basic functions and shapes.

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Construction of Ultra High Vacuum Scanning Tunneling Microscope (초고진공 Scanning Tunneling Microscope의 제작)

  • Son, Eun-Sook;Hong, Yeong-Kyu;Park, Chan
    • Journal of the Korean Vacuum Society
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    • v.3 no.4
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    • pp.377-381
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    • 1994
  • 초고진공(UHV) Scanning Tummeling Microscopy(STM)을 제작하였다. 8인치 프란지에 부착한 STM은 초고진공에서 시료의 통전가열이 가능하며 다른 표면 측정방법의 적용과시료처리가 용이하다. 외부로부터 초고진공을 깨지 않고 시료와 tip의 도입이 가능하며 tip을 가열할 수 있다. 완성된 장치로 Si(111)-7$\times$7 구조의 STM상을 얻었다.

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Thermoelectric Imaging of Epitaxial Graphene

  • Jo, Sang-Hui
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.113.2-113.2
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    • 2014
  • Heat is a familiar form of energy transported from a hot side to a colder side of an object, but not a notion associated with microscopic measurements of electronic properties. A temperature difference within a material causes charge carriers, electrons or holes, to diffuse along the temperature gradient inducing a thermoelectric voltage. Here we show that local thermoelectric measurements can yield high sensitivity imaging of structural disorder on the atomic and nanometre scales. Using this imaging technique, we discovered a defect-mediated dimensional evolution of strain-response patterns in epitaxial graphene with increasing thickness.

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A Study on the Decreasing Method of Secondary Arc Current on Single Phase Reclosing (단상 재폐로시 2차아아크 전류의 감소방법에 관한 연구)

  • 김준현
    • 전기의세계
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    • v.26 no.6
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    • pp.59-65
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    • 1977
  • A study on the decreasing method of secondary arc current on single phase reclosing. One of the major problem in case of using the single phase reclosing scheme for long distance UHV transmission line is the time required to deionize secondary arc current. This paper descritbes the way of inducing the formular of secondary arc current originated at the times of opening and closing the ground interrupting switch. The result was investigated by the method of numerical analysis and proved that the secondary arc current was decreasing sufficiently. Application of this method proposed by the authod makes it possible to deduce the dead time and to improve success-rate of reclosing.

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The Design and Aging Test of Polymer Insulator for Power Transmission and Distribution (송배전용 고분자 애자의 설계와 열화시험)

  • Lee, Un-Yong;Cho, Han-Gu;Lim, Kee-Joe
    • Proceedings of the KIEE Conference
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    • 2000.11c
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    • pp.553-555
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    • 2000
  • Recently polymer insulators are being used for outdoor high voltage applications. Polymer insulators for transmission line have significant advantages over porcelain and glass insulators, especially for ultra-high voltage(UHV) transmission lines. In this paper, the design trend and method polymer insulator are investigated and Aging test method is analysed to know life time of insulator.

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Ghost and Blocking of TV signal by UHV Transmission Lines (대형 송전선로에 의한 TV 전파장해 고찰)

  • Shin, Koo-Yong;Lee, Dong-Il
    • Proceedings of the KIEE Conference
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    • 1998.07e
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    • pp.1776-1778
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    • 1998
  • KEPCO has been constructing the 765 kV double circuit transmission line since 1997. It is worried that the 765 kV transmission lines make TV interference(Ghost and Blocking) due to high tower and multi sub-conductors. This paper presents the mechanism, the measuring method and the results of TV ghost and blocking measurement using a new TV ghost measurement system in a vehicle which was developed by KEPRI.

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The Design Analysis of Distribution Polymer Suspension Insulator (배전용 폴리머 현수애자의 설계해석)

  • Lee, Un-Yong;Cho, Han-Goo;Han, Dong-Hee;Lim, Kee-Jo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.05c
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    • pp.66-68
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    • 2001
  • Recently polymer insulators are being used for outdoor high voltage applications. Polymer insulators for transmission and distribution line have significant advantages over porcelain and glass insulators, especially for ultra-high voltage(UHV) transmission lines. Their advantages are light weight, vandalism resistance and hydrophobicity. In this paper, distribution polymer suspension insulator has been designed and investigated electric field distribution by FEM.

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Forced reclosing in transmission line (송전선의 강제재폐로)

  • 김준현
    • 전기의세계
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    • v.29 no.6
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    • pp.401-409
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    • 1980
  • This paper deals with the implementation of forced reclosing the transmission line. Because the ground circuit breaker method decrease the secondary arc current sufficiently, the reclosing time can be reduced. As the secondary arc current is large and its residual time is long in UHV transmission line, this method is more effective in that system. The resistance of ground circuit breaker which minimize the secondary arc current is determined according to the system voltage and the length of transmission line.

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A Study on A Gas Circuit Breaker Development Using Simplified Synthetic Testing Facility (간이합성시험설비를 이용한 가스차단기 개발에 관한 연구)

  • Chong, Jin-Kyo;Kim, Gyu-Tak
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.902-904
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    • 2007
  • A $SF_6$ gas circuit breakers are widely used for short circuit current interruption in EHV or UHV power system. During a $SF_6$ gas circuit breaker development, Simplified synthetic testing facility is used. This paper shows how simplified synthetic testing facility is used for a SF6 gas circuit breaker development.

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