Thermal response of bimetallic conductors under surge currents taking the skin effect into account

The author gives expressions for the losses in a bimetallic cylindrical conductor, under impulse surges, with the transient skin effect taken into account. Both the total losses in each region and ´the losses at a surface layers´ of the bimetallic conductor are considered. Expressions for a current surge in a form of dual exponential impulse are presented. Formulae obtained are used for the computations of the thermal response of the copper covered steel conductors used as the earth wires for lightning protection of overhead power transmission lines.