On the Assessment of a New Stopping Criterion for the Monte Carlo Method Applied to the Analysis of the Lightning Performance of Transmission Lines

Abstract

This paper evaluates the use of the Monte Carlo method for the assessment of the lightning performance of transmission lines. By the application of the ATP-DE-MC, an interface between the Monte Carlo method and the software ATP, the critical current and the backflashover probability for a typical 138-kV transmission line under different tower-footing grounding impedance Z <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</inf> are calculated. From the analysis of the results for different number of Monte Carlo rounds, a stopping criterion is proposed based on the simultaneous consideration of the error of the probability distribution and the dispersion coefficient. It was shown that evaluations of the lightning performance of transmission lines related to high critical current demand more Monte Carlo rounds and consequently more computational efforts and simulation time. The use of the stopping criterion provides decreases of 21% in the number of rounds for Z <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</inf> of 10 Ω and 92% for Z <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</inf> of 40 Ω and 80 Ω, maintaining consistent and feasible results that ensure its use in the Monte Carlo method execution.