• 제목/요약/키워드: neutral line

검색결과 327건 처리시간 0.027초

한전 배전 계통을 이용한 2단장주의 불평형 부하에 따른 중성선 전류의 영향에 관한 연구 (A Study on the Effects of Neutral Current by Unbalanced Load in Two Step Type Pole using KEPCO's Distribution System)

  • 박건우;서훈철;김철환;정창수;유연표;임용훈;이원정
    • 전기학회논문지
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    • 제56권3호
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    • pp.465-471
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    • 2007
  • The one step type pole and two step type pole are used in KEPCO's distribution system. The neutral current increases in three-phase four-wire distribution system due to unbalanced load. Usually, power line and communication line are installed at contiguity by effect of topography in Korea. To this end, the damages such as electrostatic induction, electromagnetic induction and harmonic induction generated by induced voltage and current are occured in power line and communication line. This paper calculates the neutral current in KEPCO's distribution system using EMTP by composing various simulated conditions. Also, these results are verified by vector analysis.

3상 비선형 부하시 중성선 전류 해석 (Neutral Line Current Analysis in Three-phase Nonlinear Load Condition)

  • 민완기;김남오;김병철;전형석;신석두;김형곤;민준기;최재호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 정기총회 및 학술대회 전문대학교육위원
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    • pp.109-109
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    • 2008
  • Neutral line current is analyzed by the neutral line CF in nonlinear load balanced and unbalanced conditions. The worst nonlinear load condition is nonlinear balanced load condition. and It is below CFNL=1.194 that a neutral line current could not excess the rated value.

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배전계통에서 1선 지락고장 시험에 의한 지락고장전류 분류에 관한 연구 (A Study on the Ground Fault Current Distribution by Single Phase-to-Neutral Fault Tests in Power Distribution System)

  • 김경철;유창훈
    • 조명전기설비학회논문지
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    • 제27권7호
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    • pp.37-44
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    • 2013
  • Phase to ground faults are possibly one of the maximum number of faults in power distribution system. During a ground fault the maximum fault current and neutral to ground voltage will appear at the pole nearest to the fault. Distribution lines are consisted of three phase conductors, an overhead ground wire and a multigrounded neutral line. In this paper phase to neutral faults were staged at the specified concrete pole along the distribution line and measured the ground fault current distribution in the ground fault current, three poles nearest to the fault point, overhead ground wire and neutral line. A simplified equivalent circuit model for the distribution system under case study calculated by using MATLAB gives results very close to the ground fault current distribution yielded by field tests.

공통중성선 3상4선식 배전선로의 중성선 전위상승에 관한 연구 (Researches on the Potential Rises on the Neutral Line in Three Phase, Four-Wire Distribution Line Systems)

  • 박영문
    • 전기의세계
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    • 제18권6호
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    • pp.23-32
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    • 1969
  • The thesis has derived the formulas and computational algorithms useful for predicting and constraining the potential rises on the neutral line in 3-phase, 4-wire distribution line systems in the case of contact faults and single-line grounding faults. In addition it has suggested economically optimal designing conditions herewith of the distribution line systems in conduction with the potential restraining cost functions.

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Characteristics of the SFCL by turn-ratio of three-phase transformer

  • Jeong, I.S.;Choi, H.S.;Jung, B.I.
    • 한국초전도ㆍ저온공학회논문지
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    • 제15권4호
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    • pp.34-38
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    • 2013
  • According to the increase of electric consumption nowadays, power system becomes complicated. Due to this, the size of single line-to-ground fault from power system also increases to have many problems. In order to resolve these problems effectively, an Superconducting Fault Current Limiter(SFCL) was proposed and continuous study has been done. In this paper, an SFCL was combined to the neutral line of a transformer. An superconductivity has the characteristics of zero resistance below critical temperature. because of this, SFCL has nearly zero resistance. so we connecting SFCL to neutral line will not only have any loss in the normal operation but also have the less burden of electric power because of only limiting the initial fault current. We analyzed the characteristics of current, voltage according to the changes of turn ratio of 3 phase system in case of combinations of an SFCL to the neutral line. It was confirmed that the limiting rate of initial fault current by the increase of turn ratio was reduced.

초전도체 및 상전도체의 변압기 2차측 적용에 따른 변압기형 SFCL 특성 비교 (Transient Characteristics of a Transformer Type SFCL Applying the Superconductor and the Normal-conductor into the Secondary Winding)

  • 정병익;최효상
    • 전기학회논문지
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    • 제65권5호
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    • pp.873-877
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    • 2016
  • This paper proposed the structure that applied superconductors to the neutral line of a transformer and applied the normal conductors to the third line. The superconductor applied to the neutral line of a transformer limited the peak value of initial fault current, while the normal conductor finally limited the fault current. In order to secure the operating reliability of transformer type Superconducting Fault Current Limiter (SFCL) of previously proposed structure, we analyzed the operating characteristics according to the fault types. We tested a line-to-ground fault and a line-to-line fault. As a result of the experiment, all the faults showed that the superconductor stably limited the peak-value of initial fault current. Also, the normal conductor finally limited the fault current. Based on this research results, We thought that if the structure of inserting superconductor into the neutral line is applied to the real system, it could improve the reliability and stability of the power system.

절연구분장치의 속도향상 기술 (Technique on the speed up of neutral section in the catenary system)

  • 창상훈;박병수;김영곤
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 춘계학술대회 논문집 전기설비전문위원
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    • pp.71-74
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    • 2005
  • At the neutral sections, There are neutral sections inserted in overhead contact line between the substations to divide different phase current sections of AC electrified lines. except convention line, a large stress occurs in the contact wire near the fittings under passing pantographs. So, in order to raise the train speed over 150km/h, a new type section has been adopted.

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중성점 스위치의 저주파 스위칭 기법을 이용한 TNPC 인버터의 효율 향상 기법 (High Efficiency Control Strategy of TNPC Inverter Using Low-frequency Switching Method of Neutral Point Switch)

  • 이태영;조영훈;임승범
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2015년도 전력전자학술대회 논문집
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    • pp.329-330
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    • 2015
  • This paper introduces a low-frequency switching method for the neutral line of TNPC inverters to achieve high efficiency. By applying the method, the switching loss in the neutral line is reduced. In order to compensate the current distortion near zero-crossing points, the partial switching strategy is applied. Both the simulation and the experimental results verify the usefulness of the proposed method.

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단상 인버터를 사용한 중성선 전류 저감 기법 (Neutral Current Reduction Method Using Single-Phase Inverter)

  • 민준기;김효성;최재호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.155-157
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    • 2005
  • This paper analyzed the adoption possibility of a low cost single phase active power filter as the neutral current reduction device in three-phase four-wire power system with the balanced or/and unbalnaced nonlinear load conditions. Proposed system can make neutral line current to within rated vale without the phase current THD change of the installed phase line.

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Zig-zag 결선 및 Open Delta 방식을 이용한 새로운 고조파 저감장치의 개발 (New harmonic drop device develop take advantage of Zig-zag TR line and Open Delta mode)

  • 유상봉;이성호;김기성
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2004년도 학술대회 논문집
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    • pp.101-104
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    • 2004
  • 지금까지의 고조파 필터는 중성선 리액터와 이중 엇갈린 결선으로 영상고조파 전류를 제거하였으나 중성선 리액터 과열로 중성선 단선 위험의 문제가 발생하였다. 본 중성선 Open Delta 방식은 이중 엇갈린 결선의 Core Block내에 결선하여 중성선에 연결하면 중성선으로 흐르는 영상 고조파 분 전류를 과열 없이 안전하게 제거하고 중성선 고조파 부하 전류량에 관계없이 완전하게 제거되는 것을 시험 분석한 결과로 가장 효과적인 고조파 저감 대책을 개선사례로 제시하여 관련선로에 도움이 되고자 한다.

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