Susceptibility of 400 kV transmission lines to bird streamers and bush fires

This paper describes the findings of a study done of the performance of two adjacent single circuit 400 kV lines in which the phase-to-ground and phase-to-tower clearances on one of the lines were increased above the standard clearances. The key finding that the design with increased clearances has been shown to withstand to a considerable degree the fire and streamer (excreta) stresses (without bird guards), whereas the standard line does not, is analysed. The implications for future designs are discussed… (more)