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http://dx.doi.org/10.5370/KIEE.2013.62.7.905

Analysis of Sequence Impedances of 345kV Cable Transmission Systems  

Choi, Jong-Kee (KEPCO Research Institute)
Ahn, Yong-Ho (KEPCO Research Institute)
Yoon, Yong-Beum (KEPCO Research Institute)
Oh, Sei-Ill (KEPCO Facility Diagnosis Center)
Kwa, Yang-Ho (KEPCO Transmission Operation Department)
Lee, Myoung-Hee (KEPCO Transmission Operation Department)
Publication Information
The Transactions of The Korean Institute of Electrical Engineers / v.62, no.7, 2013 , pp. 905-912 More about this Journal
Abstract
Power system fault analysis is commonly based on well-known symmetrical component method, which describes power system elements by positive, negative and zero sequence impedance. In case of balanced fault, such as three phase short circuit, transmission line can be represented by positive sequence impedance only. The majority of fault in transmission lines, however, is unbalanced fault, such as line-to-ground faults, so that both positive and zero sequence impedance is required for fault analysis. When unbalanced fault occurs, zero sequence current flows through earth and skywires in overhead transmission systems and through cable sheaths and earth in cable transmission systems. Since zero sequence current distribution between cable sheath and earth is dependent on both sheath bondings and grounding configurations, care must be taken to calculate zero sequence impedance of underground cable transmission lines. In this paper, conventional and EMTP-based sequence impedance calculation methods were described and applied to 345kV cable transmission systems (4 circuit, OF 2000mm2). Calculation results showed that detailed circuit analysis is desirable to avoid possible errors of sequence impedance calculation resulted from various configuration of cable sheath bonding and grounding in underground cable transmission systems.
Keywords
Zero sequence impedance; Cable transmission systems; Sheath bonding; Grounding;
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  • Reference
1 KEPCO, Study of Calculation Method of Underground T/L Impedances and Capacity (Final Report), 1991
2 Omicron, CPC-100+CP CU-1 measuring system, 2005
3 KEPCO, Report on Measurement of Sequence Impedances of 154kV Underground T/L, 2005
4 Phil Nichols,Jeremy Yarnold, "A Sensitivity Analysis of Cable Parameters and Their Influence on Design Choices for Minimum Sheath Voltage Limiter Specification in Underground Cable Systems," Power Engineering Conf. AUPEC 2009, pp. 1-6, 1992.
5 B. Gustavsen, J. A. Martinez, and D. Durbak, "Parameter Determination for Modeling System Transients.Part II: Insulated Cables," IEEE Trans. on PD, vol. 20, No. 3, pp.2045-2050, 2005.
6 KEPCO, Report on Measurement of Sequence Impedance of Shinseongdong and Kuri T/L, 2008
7 Michael Kruger, Measurement of overhead line and cable impedane values, earth impedance of large substations and electromagnetic interference between overhea lines and signal cables, using a new technology, 8th IEE International Conf. on DPSP, vol.1, pp.240-243, 2004
8 KPX, Case Studies of Power System Faults, 2010
9 KEPCO, Power System Protection Standards, 2012