On the Transient Analysis of Towers: A Revised Theory Based on Sommerfeld-Goubau Wave

Accurate tower models for fast transients are essential for the insulation design of overhead lines, since lightning may produce temporary or even permanent faults. The aim of the work is to further investigate the nature of the electromagnetic modes supported by the tower, and on the applicability of the transmission line approaches, originally inspired by the model proposed by Jordan. The influence of a perfectly conducting ground plane and of losses distributed along the tower will be discussed. A new approach, based on the Sommerfeld-Goubau wave formalism, is proposed to give physical insights on the propagation phenomenon along transmission line towers.