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Line arresters and underbuilt wire application in lightning protection of 110 kV and 220 kV overhead transmission lines

Lightning strikes are one of the most frequent cause of overhead line outages. To reduce backflashover rate of critical lines special lightning protection system must be applied. In this paper application of line arresters and underbuilt wire on 110 kV and 220 kV overhead transmission line are analyzed. Efficiencies of applied lightning protection systems are estimated through the numerical calculations performed in the EMTP-ATP software. It is concluded that both line arresters and underbuilt wire can provide high level of line lightning protection. Installation of underbuilt wire at overhead line provide better lightning protection efficiency than installation of one line arrester per tower, except in case when tower footing grounding resistance is extremely high.