On the analysis and evaluation of a transmission line upgrading assisted by line arresters

The upgrading of transmission lines has shown to be an attractive alternative regarding the increasing demand of power and the difficulties for constructing new lines. In this paper, the study performed for upgrading an essential transmission line located in an industrial area at the SE region of Brazil will be presented. As the region where the line is located presents a high isokeraunic level, a set of TLAs (transmission line arresters) have been also installed in the referred line. The installation of TLAs has the aim of coping with both lightning and switching surges within the upgraded line. As in a first stage not all the towers will have TLAs, a study for choosing the most appropriate towers will also be presented.