Research on Earth Current Characteristics of Tower Grounding Body under Different Faults in 10kV Distribution Network

Abstract

In order to study earth current characteristics of the tower grounding body of the 10kV distribution system under different faults, this paper uses EMTP-RV simulation software to establish a 10kV distribution line model. Under different neutral grounding methods and load distribution methods, the earth current characteristics of tower grounding body are studied. The simulation results show that in terms of power frequency short-circuit fault, the magnitude of earth current flowing through the grounding body are largest when single-phase short circuit occurs on 10kV side via transformer shell under low-resistance neutral grounding mehtod. Under different load distribution methods, there is a difference among the earth current of different positions along the line, but the decreasing trend along the line is the same, and the earth current is greater near the power supply. Under lightning fault, the earth current is mainly related to the lightning strike level, and is more severe than short circuit faults. The research results have certain guiding significance for the selection of the tower grounding body and application of new grounding materials such as graphite.