时间域电磁探测发射电流过冲产生原理及抑制

Current overshoot produce principle and inhibition of transmitter of time domain electromagnetic detection system

针对时间域电磁探测系统中发射电流过冲造成接收盲区的问题,建立了电流过冲产生和抑制的交流等效模型,运用电路理论对模型进行了分析,提出加速电阻增大过冲电流振荡阻尼的方法,对时间域电磁探测发射机进行了改进。实验表明改进后系统稳定可靠,并使波形早期道信号前移110μs,达到缩小近地探测盲区的目的,为时间域电磁探测全电流波形收录提供了硬件前提,也可为基于无人机的电磁法探测装备的研发提供参考。

In the time domain electromagnetic detection system, emission current overshoot can cause receiving blind area. In order to solve this problem, AC equivalent models of current overshoot produce and inhabitation are established. The circuit theory is applied to the analysis of the proposed model, and a method of accelerating resistance increase and damping of overshoot current oscillation is put forward. As a result the time domain electromagnetic detection transmitter can be improved. Experiments show that the improved system is still stable and reliable~ early signal of wave is advanced by 100 ？ s, thus reducing the detection blind area. The proposed method provides hardware premise for current waveform features of time domain electromagnetic detection. It also provides reference for the design of electromagnetic instruments on unmanned aerial vehicles.