• 제목/요약/키워드: Current transient

검색결과 1,271건 처리시간 0.027초

Analysis of Thermal Recovery Characteristics for $SF^6$ Gas-Blast Arc within Laval Nozzle (Laval Nozzle에 대한 $SF^6$ 아크의 열적회복특성 해석)

  • Song, Gi-Dong;Lee, Byeong-Yun;Gyeong-Yeop;Park, Jeong-Hu
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • 제51권9호
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    • pp.522-529
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    • 2002

  • In this paper, computer simulations of the physical Phenomena occurring in the arc region before and after current zero were carried out to evaluate the thermal recovery characteristics of a Laval nozzle. A commercial CFD program "PHOENICS" is used for the simulation and the user-coded subroutines to consider the arcing phenomena were added to this program by the authors. The computed results were verified by the comparison with the test results presented by the research group of GE Co.(General Electric Company). In order to investigate the state of the arc region after current zero, the simulation was carried out with three steps. They are steady state arc simulation, transient arc simulation before current zero, and transient hot-gas flow simulation after current zero. The semi-experimental arc radiation model is adapted to consider the radiation energy transport and Prandtl's mixing length model is employed as the turbulence model. The electric field and the magnetic field were calculated with the same grid structure used for the simulation of the flow field. The post-arc current was calculated to evaluate the thermal recovery characteristics after current zero. Compared with the results obtained by GE Co., it has been found that the critical RRRV(ratio of rise of recovery voltage) will be determined previously by this study.his study.

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Study on Transient Current Limiting Operational Characteristics of Transformer Type SFCL with Two Peak Current Limiting Function (두 번의 피크전류제한 기능을 갖는 변압기형 초전도한류기의 과도전류제한 동작 특성 연구)

  • Han, Tae-Hee;Lim, Sung-Hun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • 제29권8호
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    • pp.499-504
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    • 2016

  • In this paper, we analyzed the operational characteristics of the fault current limiting according to the amplitude of the fault current for the transformer type superconducting fault current limiter (SFCL). If the fault current happens, the superconducting element connected to the secondary coil is occurred quench and the fault current is limited. When the larger fault current occurs, the superconducting element connected to the third coil is occurred additional quench and the peak fault current is limited. We found that the fault current can be more effectively controlled through the analysis of the fault current limiting and the short-circuit tests.

  • https://doi.org/10.4313/JKEM.2016.29.8.499 인용 PDF KSCI

Lithium Transport through Partially Inactive Transition Metal Oxide Electrode in Terms of Fractal Geometry: Current Transient Analysis by Monte Carlo simulation (프랙탈 기하학을 이용한 부분적으로 비활성된 전이금속 산화물 전극을 통한 리튬 이동에 관한 연구: 몬테 카를로 시뮬레이션을 이용한 전류 추이 곡선의 해석)

  • 정규남;변수일
    • 한국전기화학회:학술대회논문집
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    • 한국전기화학회 2005년도 춘계총회 및 학술발표회
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    • pp.53-53
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    • 2005

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Review of Computational Methods for Space-time Reactor Kinetics

  • Chae, Sung-Ki
    • Nuclear Engineering and Technology
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    • 제11권3호
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    • pp.219-229
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    • 1979

  • The current status of the computational methods and computer codes for the analysis of reactor kinetics is reviewed. Computational methods which have been developed for space-dependent transient analyses are presented and recent progress in the development of methods is discussed.

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