Optimal Adjustment of Double Exponential Model Parameters to Reproduce the Laboratory Volt-Time Curve of Lightning Impulse

Abstract

This paper develops an optimization model to find the optimal values for the parameters of the double-exponential function. This function can be used to reproduce the volt-time curves of the standard and nonstandard applied impulse voltages in a software environment. Reproducing a similar applied laboratory impulse voltage in a software environment plays a crucial role in obtaining precise results and validates the model to be applied for further studies. In the literature, most of the papers use the existing standard and nonstandard models in which either an RC circuit has been used or a trial and error method has been used to approximately reproduce the applied impulse. However, more often than not, inappropriate adjustments cause a large error in the outcome results. Therefore, the proposed optimization-based approach can act as a facilitating tool for reproducing the nonstandard volt-time curves as close as possible to the laboratory applied impulse. The proposed model is verified by reproducing the volt-time curve of a 125 kV impulse voltage. Comparing the simulated impulse with the experimental impulse voltage shows the usefulness and effectiveness of the proposed approach in adjusting the sensitive parameters of the double-exponential function in EMTP-RV (Electromagnetic Transients Program) software.