A new calculation method of voltage rise of transmission towers and transmission lines by lightning stroke and calculated results

New formulas for the surge impedances of transmission towers and transmission lines in lightning surge are derived. A comparison of results calculated by the proposed formulas with the experimental results show nearly the same wave crest values and wave-forms. It is demonstrated that a large portion of the input current flows into the tower and only a small current flows into the ground wires. This fact is very important in investigating lightning performance in transmission towers and transmission lines. The results will be helpful in developing improved modes of transmission system performance.