Experimental Studies of the Transient Characteristics of a Deeply Buried Grounding Electrode and a Grounding Mesh

Abstract

SUMMARYWhen lightning strikes the tower of a cellular phone base station or other such facility, power and communications equipment in the vicinity of the tower may suffer extensive damage due to the lightning current flowing backward from the grounding system of the tower. The use of a deeply buried grounding electrode has been proposed recently to suppress such backflow currents and potential rises in the vicinity of towers. The deeply buried grounding electrode is a bare conductor buried deeply in the ground, which is connected to a lightning rod on the ground by an insulated wire. When lightning strikes the lightning rod, the lightning current is directed to the electrode, from which it diffuses to the ground. Deeply buried grounding electrodes have been installed at cellular phone base stations and other such facilities to solve problems caused by backflow currents and potential rises. A grounding mesh is usually laid around such base stations as a grounding system for the facilities on the ground. Therefore, it is important to understand the interactions between the deeply buried grounding electrode and the grounding mesh. In this paper, experiments on the interactions between a grounding mesh and a deeply buried grounding electrode are described. Additionally, the transient characteristics of the mesh grounding have been investigated. © 2013 Wiley Periodicals, Inc. Electron Comm Jpn, 96(12): 52–60, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11488