| 摘要 |
PURPOSE:To detect surely electrical discharge phenomena with a simple sensor, by detecting electromotive force induced in looped electric conductors according to the change of magnetic flux in an electromagnetic field which is generated by a lightening discharge in thundercloud, etc. CONSTITUTION:As looped electtic conductors 6 are electrostatically shielded by a steel tower 1, no voltage is generated at both the ends of a resistance 5 as far as a lightening discharge does not occur a big change in the electromagnetic field. When the lightening discharge, however, in thundercloud 8 is generated, an electromagnetic field H varying in a paralel direction comes to the steel tower 1 which stands at a distance remote from the discharging point, and a voltage is generated in the looped electric conductors 6, accordingly at both the ends of the resistance 5. The voltage is inputted into an integrator 14 through a full-wave rectifier 13 and an output of the integrator 14 is displayed by a display device 15. By this method, an extent of approaching thunder is surely detected. |
