Study on Temperature Rise Characteristics of Tower Grounding Electrode Under Lightning Strike and Power Frequency Short-Circuit Conditions

In order to study the temperature rise characteristics of tower grounding under lightning strike and power frequency short circuit conditions, this paper first calculates the current flowing into the tower grounding device under lightning strike and power frequency short circuit conditions. The calculated current flowing into the underground is taken as the terminal condition of the finite element simulation model of the tower grounding electrode. Low carbon steel and graphite wire and graphite belt are used as simulation grounding materials to analyze the temperature rise characteristics and influencing factors of the grounding electrode under lightning strike and power frequency short circuit conditions. The results show that when the lightning current and power frequency short circuit current flow into the grounding electrode, the temperature rise at the down lead of the grounding electrode is significantly higher than that at other positions of the grounding electrode, and the temperature rise of the down lead exposed to the air is the highest. The temperature rise of grounding electrode increases with the increase of current amplitude. The temperature rise of flexible graphite grounding material under power frequency short-circuit current may exceed its temperature tolerance limit, while the temperature rise of grounding electrode caused by lightning current is small.