EXPERIMENTAL EVALUATION OF A UHV TOWER MODEL FOR LIGHTNING SURGE ANALYSIS

An experimental investigation was performed on a UHV tower model for t he EMTP multiconductor calculation of lightning overvoltage at substat ions associated with back-flashover at an adjacent transmission tower. The various lightning surge response characteristics were measured on an actual UHV tower, and parameters of a multistory transmission towe r model that can reproduce voltages across the insulator strings, volt ages of the crossarms, and voltages of the power lines were determined . A value of 120 Omega was determined as the surge impedance at each s ection of the multistory tower model, which closely agreed with the to wer surge impedance measured for the UHV tower alone.