High frequency performance of an earthing system

摘要

Vertical earth rods are very importantrncomponents of lightning protection. They are used inrntransmission and distribution systems.rnA detailed parametric analysis is carried out torncharacterise the performance of an earth rod usingrnearth design software (HIFREQ module [1]) and twornequivalent circuits (Lumped and Distributed circuits).rnSeveral works has been don on the characteristics ofrnthe earth rod under transients [2-7]. The BritishrnStandard is recommended 10 ohm earth electrodernresistance [8].rnThis paper presents the performance of the earthrnelectrode over a high range of frequencies from 50 Hzrnto 50 MHz. The parameters that are varied arernfrequency, rod length, rod radius, soil resistivity andrnsoil permittivity.rnAlso the models are studded under number of impulsernsurges.rnThe earth rod used in the simulation, of 5m length andrn7mm radius.