# 케이블 열회로의 전기적 등가회로 변환을 이용한 케이블 허용전류 검토 방법

Kang, Yeon-Woog;Kim, Min-Ju;Jang, Tae-In;Park, Jin-Woo;Park, Hung-Sok;Kang, JI-Won
강연욱;김민주;장태인;박진우;박흥석;강지원

• Accepted : 2016.04.17
• Published : 2016.05.01
• 38 135

#### Abstract

Current rating of a power cable can be calculated by the maximum allowable temperature in an insulating material considering the heat transfer from cable conductor. Therefore, it is very important to calculate the current rating using electrical equivalent circuit by calculated cable thermal circuit parameters but, it has not been fully investigated yet. In this paper, in order to determine the current rating of power cable, conventional calculation method has been reviewed considering the conductor resistance, loss factor of sheath, dielectric losses and thermal resistances based on the maximum allowable temperature of 345 kV $2500mm^2$ XLPE cable. To confirm the calculation result of the current rating, the conductor temperature should be examined whether it reaches the maximum allowable temperature by the thermal equivalent circuit of the cable. Then, utilizing EMTP (Electro-Magnetic Transient Program) which is a conventional program for electrical circuit, the thermal equivalent circuit was transformed to an electric equivalent circuit using an analogous relationship between thermal circuit and electrical circuit, and temperature condition including cable conductor, sheath, cable jacket could be calculated by the current rating of 345 kV $2500mm^2$ XLPE cable.

#### Keywords

Cable;Thermal circuit;Electrical equivalent circuit;Ampacity

#### References

1. Neher, J. H., and M. H. McGrath. 1957. "The Calculation of Temperature Rise and Load Capability of Cable systems". AIEE Transactions on Power Apparatus and Systems. Vol. 76. October.
2. IEC 60287, "Electric cables - Calculation of the current rating", 2006.
3. IEC 60853, "Calculation of the cyclic and emergency current rating of cables", 2006.
4. EPRI Underground Transmission Systems Reference Book, 2006 Edition, EPRI