Abstract：Graphite based flexible grounding materials are used in transmission line tower grounding body because of their stable chemical properties, excellent corrosion resistance and good compatibility with soil. However, their adaptability must be determined according to the transmission energy, tower position and operation environment of transmission line. In this paper, the finite element simulation models of different transmission line tower grounding devices are established, and the corresponding grounding resistance is calculated. According to the value of grounding resistance, using ATP-EMTP software, the current flowing through the grounding device under grounding short circuit and lightning impulse current and temperature rise are calculated. The applicability of graphite based flexible grounding device in transmission line is studied from two aspects of grounding resistance, temperature rise under power frequency short circuit current and lightning impulse current. The research results show that the power frequency grounding resistance required by the regulations meets the requirements of transmission line tower grounding resistance, but in case of single-phase grounding short-circuit fault of UHV transmission line, the failure of protection will make the temperature rise of grounding device exceed the limit value.
2021, Vol. 22 
