An expeditious calculation approach to consider the influence of power frequency voltage on the calculation of the lightning performance of transmission lines: Validation for different peak current-front time correlation expressions and cumulative peak current distributions

•The quality of the 0.88-factor approach in comparison to Monte Carlo method is shown.•Analyses considered the correlation between peak current and front time.•Different cumulative peak current distributions were assumed in simulations.•Transmission lines with voltage level from 69 to 500 kV were considered.•Ratio between backflashover rate by the 0.88-factor and Monte Carlo method is around 1. The approach to consider the influence of the power-frequency voltage on the calculated lightning performance of transmission lines with voltage level from 69 kV to 500 kV by means of the 0.88-multiplying-factor applied on critical currents is validated for simulation conditions that assume the correlation between lightning peak current and front time, and several cumulative peak current distributions of negative first strokes. The obtained results confirm that the relation between critical currents calculated in the presence and in the absence of the power-frequency voltage follows the 0.88-factor for all investigated cases. The root mean square errors (RMSE) calculated for the critical currents vary from 3.20 kA to 7.37 kA and for the backflashover probability are not greater than 0.02 %, ensuring the generality of application of the proposed approach. The ratio between the backflashover rates obtained by the 0.88-factor approach and by the Monte Carlo method is around 1 for most of the simulated cases, confirming the quality of the results provided by such expeditious procedure.