• 제목/요약/키워드: UHV

검색결과 207건 처리시간 0.034초

Couette 흐름현상을 이용한 초고압변압기의 유동대전 기구 연구 (A Study on the Electrification Mechanism in UHV Transformer by Couette Flow)

  • 곽희로;정용기;권동진
    • 한국조명전기설비학회지:조명전기설비
    • /
    • 제9권4호
    • /
    • pp.93-102
    • /
    • 1995
  • The purpose of this paper is to analyze the streaming electrification mechanism (SEM) generated in UHV transformer. This experiment used Couette Charger and interpreted the mechanism hydromechanically and electromagnetically. This work estimated the turbulent core density ($\rho$o) by measuring the short circuit current (isc) and the open circuit voltage (νoc) generated in Couette Charger and also studied the changes of the short circuit (isc), the open circuit voltage (νoc), the turbulent core density ($\rho$o) and the conductivity ($\sigma$) with adding BTA to restrain streaming electrification. as a result adding BTA increased the conductivity of oil and decreased the turbulent core density($\rho$o).

  • PDF

초고진공용 부품 적용을 위한 스테인리스 스틸과 구리의 용접 (Welding of Stainless Steel to Copper for UHV Component Application)

  • 흥만수;김경렬;박종도;김영찬;정진화
    • 대한용접접합학회:학술대회논문집
    • /
    • 대한용접접합학회 2004년도 추계학술발표대회 개요집
    • /
    • pp.243-245
    • /
    • 2004
  • 가속기의 저장링 및 빔라인에는 방사광을 차단 혹은 일부 통과 둥의 목적으로 Photon Absorber와 같은 진공 부품이 사용되고 있으며, 이는 일반적으로 구리와 스테인리스 스틸 등의 이종재료를 브레이징 공정을 이용하여 제작함으로써 부품이 구조적 건성의 확보와 더불어 진공환경 및 수밀을 유지하고 있다. 그러나, Photon Absorber는 사용 용도에 따라 구조적 형상이 서로 다르기 때문에 브레이징 공정을 적용하는 경우, 상대적으로 제품 생산가격의 상승, 유지보수 및 제작불량에 따른 공정 제어의 어려움이 나타나고 있다. 본 연구에서는 스테인리스 스틸 (STS 304)과 구리(OFHC Copper)의 이종금속에 접합에 GTAW 용접 공정 기술을 적용하여 제반 용접공정에 따른 용접부 성능 및 진공 특성 등을 검토하였다. 용접봉 (ER CuSi-A)을 직접 사용하여 이종 재료의 시험편에 GTAW 용접을 적용한 결과, 진공 누설율은 $1{\times}10^{-10}\;Torr{\cdot}l/s$ 이하를 얻을 수 있었으며, 용접 접합부의 인장강도 210 MPa로써 구리 모재와 유사한 기계적 특성을 나타내었다.

  • PDF

UHV변압기에서 유동대전에 의한 사고 방지에 관한 연구 (A Study on the Preventive Method of Accident by Streaming Electrification in UHV Transformer)

  • 박재윤;고희석
    • 한국조명전기설비학회지:조명전기설비
    • /
    • 제6권5호
    • /
    • pp.38-44
    • /
    • 1992
  • In this paper, electrification pipe modeled on the oil path that insulating oil flow in the high power transformer is manufactured in order to prevent the accident cause from streaming electrification generated when insulating off flow at a solid-liquid interface, and the streaming current is measured and analyzed according to the shape of oil path in electrification pipe. From the result of this study, the streaming current increases linearly with increasing of a oil velocity and it increases at lower temperature and decreases at higher temperature than [$46^{\circ}C$]. The smoother the flow of insulating oil is the more the streaming current decreases.

  • PDF

Hydrogen concentration and critical epitaxial thicknesses in low-temperature Si(001) layers grown by UHV ion-beam sputter deposition.

  • Lee, Nae-Eung
    • Journal of Korean Vacuum Science & Technology
    • /
    • 제3권2호
    • /
    • pp.139-144
    • /
    • 1999
  • Hydrogen concentration depth profiles in homoepitaxial Si(001) films grown from hyper-thermal Si beams generated by ultrahigh vacuum (UHV) ion-beam sputtering have been measured by nuclear reaction analyses as a function of film growth temperature and deposition rate. Bulk H concentrations CH in the crystalline Si layers were found tio be below detection limits, 1${\times}$1019cm-3, with no indication of significant H surface segregation at the crystalline/amorphous interface region. This is quite different than the case for growth by molecular-beam epitaxy (MBE) where strong surface segregation was observed for similar deposition conditions with average CH values of 1${\times}$1020cm-3 in the amorphous overlayer. The markedly decreased H concentrations in the present experiments are due primarily to hydrogen desorption by incident hyperthermal Si atoms. Reduced H surface coverages during growth combined with collisionally-induced filling of interisland trenches and enhanced interlayer mass transport provide an increase in critical epitaxial thicknesses by up to an order of magnitude over previous MBE results.

  • PDF

초고압 송전선로의 다도체 구성에 따른 불평형 전류 해석 (Unbalace Current Analysis on the Bundled Conductors of the UHV Overhead Transmission Line)

  • 정연호;이형권;손홍관;조연규
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 하계학술대회 논문집 C
    • /
    • pp.1379-1381
    • /
    • 1999
  • The unbalance current on the bundled conductors of the UHV overhead transmission line is one of the factors affected on power transmission system. It is varied by distance between of bundled conductors and of phase to phase, phase arrangement. In this paper, we calculated unbalance current on the bundled conductors by a variety of line arrangements and also calculated magnetic field at the circumference of the line fed with this unbalance current.

  • PDF