根据电磁感应法原理,研制了一套全相闪电磁场测量系统。该系统磁场测量天线由3个正交的半径为15 cm的环状天线构成,由高速大容量示波记录仪完成数据采集,采用基于全电路表达式的脉冲磁场数字重构法对数据进行还原处理。利用该系统,结合电场变化观测系统和高速摄像系统,在广东省从化地区开展了闪电的光、电、磁场同步观测试验。试验资料分析表明,该套全相磁场测量系统观测的闪电磁场变化基本真实可靠。
In order to have a better understanding of the characteristics of lightning magnetic fields, an allphase magnetic field measurement system is developed, in which the electromagnetic induction method is used. The sensor consists of three 15 cm radius orthogonal magnetic loops. The data is recorded by an oscilloscope with high speed and high capacity. The pulse magnetic field waveform digital reconstruction method based on the full circuit equation is adopted in data restoration processing. The system is calibrated by a current generator with a maximum output of 6 kA in laboratory. The synchronized electric and magnetic observation data of two lightning flashes observed in the field experiment conducted in Conghua, Guangdong Province, is analyzed. It is found that the all-phase magnetic field measurement system can reliably reflect lightning magnetic field change.