실계통 345kV 지중송전선 대칭좌표 임피던스의 해석

다국어 초록 (Multilingual 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.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 본론
• 3. 결론
• References

참고문헌 (Reference)

1 KEPCO, "Study of Calculation Method of Underground T/L Impedances and Capacity (Final Report)" 1991

2 KEPCO, "Report on Measurement of Sequence Impedances of 154kV Underground T/L" 2005

3 KEPCO, "Report on Measurement of Sequence Impedance of Shinseongdong and Kuri T/L" 2008

4 KEPCO, "Power System Protection Standards" 2012

5 B. Gustavsen, "Parameter Determination for Modeling System Transients.Part II: Insulated Cables" 20 (20): 2045-2050, 2005

6 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" 1 : 240-243, 2004

7 KPX, "Case Studies of Power System Faults" 2010

8 Omicron, "CPC-100+CP CU-1 measuring system" 2005

9 Phil Nichols, "A Sensitivity Analysis of Cable Parameters and Their Influence on Design Choices for Minimum Sheath Voltage Limiter Specification in Underground Cable Systems" 1-6, 1992