Simulation of the impact of lighting on the ground wire in 400 kV transmission lines

Due to the importance of the hydroelectric project of 400 kV Tocoma for compliance with the requirements of demand, with high operational safety, we present the development of this work. Its objective consists in to analyze the behavior of the isolation of the transmission towers to the entrance of the bay of the substation due the impact of lightning on ground wire. We obtain the behavior of the line considering lightning of 5 and 20 kA and ground resistance at the foot of the tower of 0, 20, 100 and 400 Ω, using the simulation program PSCAD / EMTDC. The results show that none of the simulated cases are above the recommended level for line; however, to lightning of 20 kA and 400 Ω of resistance, the tension obtained of phase to ground is twice normal operation of the system, a value close to the limit let to the system.