Simultaneous measurement of return-stroke current and E-field waveforms at southern Kyushu in Japan

To establish effective countermeasures on power facilities against lightning damage, it is necessary to clarify the lightning characteristics such as current parameters at the area of interest. In order to collect lightning current parameters effectively, the authors have observed electric and magnetic field waveforms simultaneously at southern Kyushu, where the lightning flash density in summer is high. Based on observed electric field waveforms, the lightning current parameters have been estimated, and the accuracy has been demonstrated by comparison with statistics of directly measured current waveforms. In this paper the accuracy of the estimated return-stroke current waveform is verified by comparison with directly measured return-stroke current waveform, along with the accuracy of the estimated charge transfer from the electric field waveform measured with a slow antenna.