EVALUATION OF LIGHTNING RETURN STROKE CURRENT USING MEASURED ELECTROMAGNETIC FIELDS

The lightning return stroke current is an important parameter for considering the efiect of lightning on power lines. In this study, a numerical method is proposed to evaluate the return stroke current based on measured electromagnetic flelds at an observation point in the time domain. The proposed method considers all fleld components and the full wave shape of the current without the use of a special current model as a basic assumption compared to previous methods. Furthermore, the proposed algorithm is validated using measured flelds obtained from a triggered lightning experiment. The results show a good agreement between the simulated fleld based on the evaluated currents from the proposed method and the corresponding measured fleld at a remote observation point. The proposed method can determine current wave shapes related to a greater number of lightning occurrences compared to the direct measurement of the current.