A Study on an Impact of Tower Surge Impedance Against Lightning Surge Phenomena

Abstract

Abstract Lightning strikes creates damages to the electrical power system utilization and equipment. To reduce the effect of lightning strikes in the tower transmission, the ground resistance of the tower must be kept to a low value of less than 5 Ω. This research is a study of tower surge impedance using additional conductor line connected by parallel two overhead ground wire at the top of the tower transmission line. The additional of ground wire which is connected from the top of the tower utilizes copper and aluminium alloy for the simulation. Calculation of tower surge impedance using finite element method by COMSOL in 3D simulation based on traditional electromagnetism equations. Surge impedance values were calculated, and it was found that the calculation results obtained with less than 0.5 % error when using finite element method compare with conventional numerical method. Aluminium alloy conductor was found to have an effect on reducing the overvoltage magnitude of lightning strikes at the tower transmission line when compare with copper conductor.