Experimental Study on Impact Grounding Characteristics of Transmission Line Tower

摘要

There is a big difference between the impact grounding impedance and the power frequency grounding impedance. The measurement of the power frequency grounding impedance alone cannot effectively reflect the impact characteristics of the grounding body under lightning. In this paper, the effects of the impact current amplitude, injection point and soil resistivity on the impact characteristics of the transmission line tower grounding grid model are studied by means of simulation test. The results show that the grounding impedance of the grounding body decreases with the increase of the amplitude of the injected current. The impact coefficient of the grounding body is larger than that of the multi-point injection when the single current is injected. The lower the soil resistivity, the lower the impact coefficient of the grounding grid. The research results of this paper can provide reference data for proposing and verifying the new tower grounding impedance measurement principle and test equipment.