• Title, Summary, Keyword: EMTP/ATPDraw

Search Result 62, Processing Time 0.04 seconds

Field Test and Analysis for Proper Location of Protective Equipment in Underground Distribution System (지중배전계통 보호설비 적정위치 선정을 위한 실증시험과 해석)

  • Yun, Chang-Sub;Lee, Jong-Beom
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.57 no.5
    • /
    • pp.773-782
    • /
    • 2008
  • This paper describes the method for proper location of protective equipment in underground distribution cable through field test and analysis at testing lines. To prove the reliability for analysis simulated by EMTP/ATPDraw, the testing results obtained by the real test and the analysis for the same test lines were compared each other. The accuracy of analysis was proved by the comparison. Over voltages were measured and analyzed at each point of cable and switches in case of which lightning surge current was applied. The analysing method was applied to real distribution systems to select the proper location of protective equipment. It is evaluated that the location of protective equipment was properly selected.

Scott Transformer Modeling for EMTP (EMTP를 위한 Scott변압기 모델링)

  • Cho, Sung-Don
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.387-389
    • /
    • 2005
  • Scott 결선 변압기는 3상전원에서 단상부하를 공급해야하는 계통에서 많이 사용되고 있다. 특히 전기철도가 이에 해당되며 국내에서는 전기철도의 화장으로 Scott변압기가 154kV급의 송전계통에 연계되어 설치 운전되고 있다. Scott변압기의 특성상 단상인 부하측 또는 3상인 전원측에서 사고 발생시 각상에 흐르는 불평형 사고전류의 예측이 어려워 관련기기의 선정과 각종 보호계전기의 정정이 쉽지 않았으며 과도현상 해석도 쉽지않았다. ATP(Alternative Transient Program)는 전력계통의 과도현상뿐만 아니라 단락 및 지락과 같은 정상상태 해석 및 고조파 분석도 가능하며 그래픽 유저 인터페이스를 위한 ATPDraw도 개발되어 데이터 입력과 사용법이 보다 간편하게 되었으며, 출력파형을 위한 PlotXY도 개발되어 계산결과를 다양한 형태의 그래프로 출력할 수 있게 되었다. 무엇보다도 User Group에 가입하면 무료로 모든 프로그램을 사용할수 있는 장점도 있다. 본고에서는 ATP를 사용하여 Scott변압기의 모델링과 이를 통한 단락 및 지락 사고 둥의 해석 사례를 소개하였다.

  • PDF

Lightning Surge Analysis on Underground System in DC Combined Distribution System (DC 혼합배전시스템에서 지중계통의 뇌과전압 해석)

  • An, Chun-Yong;Lee, Jong-Beom
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.62 no.6
    • /
    • pp.737-743
    • /
    • 2013
  • This paper describes the overvoltage through lightning surge analysis on underground system in DC combined distribution systems. It is considered that operating micro grid including distributed generation with smart grid can make possibility of composing new distribution system different from existing one. However, there are many papers about low voltage DC distribution in grids or buildings but not many about replacement or distributing 22.9kV AC distribution system to DC system. Among many research need for DC system development, overvoltage is studied in this paper. Overvoltage is simulated on DC cable when lightning strikes to overhead grounding wire which is installed at the nearest location from power cable section. Analysis as well as modeling is performed in EMTP/ATPDraw. It is evaluated that analysis results can be used to design of DC underground distribution power cable system.

Proper Cable Arrangement Selection by Induced Voltage Evaluation of DC Cable in AC/DC Hybrid Combined Transmission Systems (AC/DC 하이브리드형 혼합송전계통에서 DC 케이블의 유도전압평가에 의한 적정배열 선정)

  • Son, Yong-Dae;Lee, Jong-Beom
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.5
    • /
    • pp.680-688
    • /
    • 2015
  • Hybrid type combined transmission systems is being operated by AC and DC line at the same space will be expanded instead of the overhead line. However, such hybrid type combined system has problem like the arrangement selection of DC cable for effective system operation. In this paper, to select the proper arrangement of DC cable, induced voltage of DC cable influenced by AC cable was analyzed in case of several type arrangement of DC cable. Such induced voltage is in detailed analyzed not only in case of steady, but transient state. The arrangement which has the lowest induced voltage is selected as the proper one. EMTP/ATPDraw is used for modeling and analysis of hybrid type combined transmission system.

Proposition of Improved Neutral Grounding Method and Analytical Evaluation on Practicality in Underground Distribution System (지중배전시스템의 개선된 중성점 접지방식 제안과 실효성에 대한 해석적 평가)

  • Jeong, Seok-San;Lee, Jong-Beom;Jang, Seong-Whan;Kim, Yong-Kap;Kwon, Shin-Nam
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.3
    • /
    • pp.479-485
    • /
    • 2011
  • In 22.9kV underground distribution system, power cables are provided with multiple-point ground in which each neutral line of the distribution cable(A, B, C phases) and three-wire common grounded at every connecting section. But in such grounding methods, circulating current flows between the neutral wire and grounding wire. And power loss due to circulating current also occurs in all conductors. Therefore it is getting necessary reducing circulating current in underground distribution system. This paper presents improved grounding method to overcome such problems. The proposed grounding method eliminates circulating current in the neutral line effectively and is verified that there is no electrical problem or any ineffectiveness of operating protection systems. These analyses are carried out by EMTP/ATPDraw to compare each grounding methods in steady and transient state. This grounding method suggested in this paper can be applied on real distribution system after field tests considering elimination of circulating current was implemented.

Suitability Evaluation on Joint Operation of Neutral Wire and Overhead Grounding Wire through Lightning Surge Analysis in Combined Distribution System (혼합배전계통에서 뇌과전압 해석을 통한 중성선과 가공지선 혼용 운전의 타당성 평가)

  • Jeong, Seok-San;Lee, Jong-Beom;Kim, Yong-Kap;Song, Il-Keun;Kim, Byoung-Suk
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.59 no.12
    • /
    • pp.2135-2142
    • /
    • 2010
  • This paper studies the validity about a joint operation of neutral wire and overhead grounding wire in combined distribution systems. The overhead grounding wire and neutral wire are currently installed separately and grounded by common. However there is no any ineffectiveness or electrical problem in case of the proposed system, such system can be operated at real distribution system. Therefore this paper describes the suitability of a joint operation through lightning surge analysis on combined distribution systems. Lightning surge analysis is carried out by EMTP/ATPDraw to obtain the overvoltage of overhead line and underground cable in various conditions such as locations and current types of lightning stroke. Overvoltage gained by the analysis show that the insulation strength of the joint operation case is not stable compare with the current operation case.

Effectiveness Evaluation on Combined Connection Operation of OF and XLPE Cable (지중송전계통에서 OF 및 XLPE 케이블 혼용 연계 운용의 효용성 평가)

  • Chea, Jik-byoung;Lee, Jong-Beom
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.6
    • /
    • pp.857-863
    • /
    • 2015
  • OF cable with excellent reliability and economic efficiency, has been used as the main cable of underground transmission in Korea. However, as XLPE cable is excellent in view points such as reduction of loss, convenience on the construction/operation, and manufacturing technology, it has been replaced as instead of OF cable. Also, when the aging occurs in some sections of OF cable, the section is replaced as XLPE cable without changing of whole cable line. However, there are some differences like electrical constants between both types of cables. Therefore if underground transmission system will be operated as combined connection composited of both cables, it should be proved that overvoltage is stable in steady and transient state. This paper describes the effectiveness of connection operation in combined OF and XLPE cable. For the evaluation of effectiveness, some important analysis such as sheath component voltage, lightning and switching overvoltage, single line-to-ground fault are carried out in steady and transient state. EMTP/ATPDraw is used for modeling and analysis of system.

Characteristics of Sheath Circulating Current by Underground Transmission Systems Analysis (지중송전시스템 해석을 통한 시스순환전류 특성 분석)

  • Jung, Chae-Kyun;Lee, Jong-Beom;Kang, Ji-Won
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.449-451
    • /
    • 2002
  • Sheath circulating current rises from the change of sheath mutual impedance which is caused by imbalanced cable system, and different section length between joint boxes. However, mixed burying typo and imbalance section length take many parts of main reasons of sheath circulating current increment in domestic underground transmission power cables. Therefore, the increment reason and variation characteristics of sheath circulating current is analysed with simulation using EMTP/ATPDraw and measuring data of practical cable system which has a problem of exceeding sheath circulating current in this paper.

  • PDF

A Study on the Characteristic and Rising Cause of Sheath Circulating Current by Analysis and Measurement (해석 및 측정을 통한 시스순환전류 특성 및 상승원인 검토)

  • Gang, Ji-Won;Yang, Hae-Won
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.51 no.10
    • /
    • pp.525-533
    • /
    • 2002
  • It is common to install multiple lines in the same route. Recently, excessive sheath circulating current was partially measured in underground cable systems of KEPCO. Especially, the installation type, unbalance section length between joint boxes and zero sequence current by distribution cable have an effect on the rising of sheath circulating current in the underground transmission system. If excessive current flows in sheath, sheath loss which is reduced the transmission capacity is produced. This paper describes the relation analysis of sheath circulating current and burying types. And also, a detailed analysis on rising cause and characteristic of sheath circulating current by considering various unbalanced conditions presents using analysis and measurement regarding cable systems which have the problem of excessive sheath circulation current.

Protection of Insulation Joint Box and Analysis of Overvoltage in Underground Power Cable Systems (지중송전케이블계통에서 절연통 보호대책 및 과전압 해석)

  • Hong, Dong-Suk;Jin, Hye-Young;Jung, Che-Kyun;Lee, Jong-Beom;Cho, Han-Ku
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.380-382
    • /
    • 2001
  • This paper describes the protection of insulation joint box in combined transmission line which is connected with the 154kV underground power cables. An actual power cable system was selected to establish modeling and to analyze. Modeling was established in EMTP and ATPDraw. Simulation was carried out according to the buried method of cable and connection method of CCPU. Results presented in this paper will be applied to another power cable systems.

  • PDF