Computation of tower surge impedance in transmission line

This paper deals with computation of transmission line tower surge impedance of a twin circuit 220kV transmission line using Finite Element Analysis (FEA). The capacitance method was used, but two different ways of computing capacitance were investigated. Computation results were compared with experimental data and other numerical methods. It was shown that the capacitance computed by FEA provides a better estimation of the tower surge impedance than any other methods and also can accommodate complexities such as the presence of guy wires.