地面长导线发射机电流快速关断技术研究  

Research on fast current turn-off technology of long wire transmitter on ground

作　　者：真齐辉 王中兴[1,2,3] 底青云[1,2,3] 王煜亮 ZHEN QiHui;WANG ZhongXing;DI QingYun;WANG YuLiang(Key Laboratory of Deep Petroleum Intelligent Exploration and Development,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;Innovation Academy for Earth Science,Chinese Academy of Sciences,Beijing 100029,China;College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院地质与地球物理研究所,中国科学院深层油气理论与智能勘探开发重点实验室,北京100029 [2]中国科学院地球科学研究院,北京100029 [3]中国科学院大学地球与行星科学学院,北京100049

出　　处：《地球物理学报》2024年第12期4574-4582,共9页Chinese Journal of Geophysics

基　　金：国家重点研发计划"混场源多参数航空电磁勘探技术与装备开发"项目(2023YFC2907100)课题三"大深度半航空瞬变电磁勘探装置开发"(2023YFC2907103)资助。

摘　　要：发射机是地面人工源电磁勘探的关键装备,在相同发射电流条件下,极距越大,信噪比越高,探测效果越好.大极距所需长导线具有较强电感(地面1 km导线约有3 mH电感),发射电压1000 V,发射电流50 A,3 mH电感的电流关断时间为103.95μs,对于时间域电磁勘探,观测信号的信噪比与关断时间对数成反比,关断时间每下降10倍,信噪比提升10 dB.本文通过在发射回路中加入快速关断开关,引入辅助关断电压,形成电流高压释放回路,有望实现1 km长导线条件下的关断时间小于10μs,观测数据信噪比提高10 dB以上,具有重要的理论意义与工程价值.Transmitter is the key equipment for electromagnetic exploration of ground artificial source.Under the same transmitting current condition,the larger the pole distance and the higher the signal-to-noise ratio,the better the detection effect.The long wire required for large pole distance has strong inductance(about 3 mH inductance of the 1 km wire).The current turn-off time of the 3 mH inductor is about 103.95μs under the condition of 1000 V transmitting voltage and 50 A transmitting current.For electromagnetic exploration in the time domain,the signal-to-noise ratio of the observed signal,which is inversely proportional to the logarithm of the turn-off time,improved by 10 dB with the turn-off time decreases 10 times.In this paper,by adding a fast turn-off unit to the transmitting loop and introducing an auxiliary turn-off voltage to form a current high-voltage release loop,the turn-off time under the condition of 1 km long wire is expected to be less than 10μs,and the signal-to-noise ratio of observed data is increased by more than 10 dB,which has important theoretical significance and engineering value.

关 键 词：电磁勘探发射机 大极距 长导线 寄生电感 快速电流关断 

分 类 号：P631[天文地球—地质矿产勘探]