A method for calculating the breakdown voltages of long air gaps in transmission lines: evaluation of the lightning performance of transmission lines using no shield wire

摘要

The possibility of abandoning the shield wire on EHV-UHV transmission lines has been examined. Insulation lengths required to obtain an acceptable lightning performance of lines have been determined. Experimental data indicate that unshielded lines can be built using conventional metal or ferroconcrete towers and lengthened insulator strings. However, the highest cost efficiency is achieved with towers made of insulating concrete or composite polymeric elements, since this substantially reduces the tower height and thus the consumption of materials.