Mutual Influence of a Deeply Buried Grounding Electrode and the Surrounding Grounding Mesh

In recent years, the ripple effects of damage to home electrical appliances of private residences near a cellular phone base stations due to lightning strikes on the station have become a problem. The damage is primarily caused by the ground potential rise of cellular phone base stations during lightning strike. To prevent such damage, instead of conducting lightning current from the grounding system of cellular phone base stations to the ground, a deeply buried grounding electrode that releases the lightning current deep into the ground through a separate grounding line has been employed in some cellular phone base stations. However, this technique is not versatile and may lead to a large overvoltage in the insulated conducting wire of the deeply buried grounding wire and may cause a dielectric breakdown, thus causing concern that this technique can no longer fulfill its role. Therefore, in this paper, we study the effectiveness and problems of employing deeply buried grounding electrodes using the finite-difference time-domain method.