半航空频率域电磁探测三分量线圈传感器设计  

Design of the three-component coil sensor for semi-airborne frequency domain electromagnetic detection

作　　者：滕飞[1,2] 王鹏飞[1,2] 王宇[1,2] 张铭 林君[1,2] TENG Fei;WANG PengFei;WANG Yu;ZHANG Ming;LIN Jun(Key Laboratory of Geophysical Exploration Equipment,Ministry of Education of China,Changchun 130061,China;College of Instrumentation and Electrical Engineering,Jilin University,Changchun 130061,China)

机构地区：[1]地球信息探测仪器教育部重点实验室,长春130061 [2]吉林大学仪器科学与电气工程学院,长春130061

出　　处：《地球物理学报》2023年第1期430-441,共12页Chinese Journal of Geophysics

基　　金：国家自然科学基金重大科研仪器研制项目(41827803);国家自然科学基金青年基金(42004150)项目;吉林大学研究生创新研究计划项目(101832020CX185)资助.

摘　　要：半航空频率域电磁探测方法(semi-airborne frequency domain electromagnetic method,简称SAFEM)通常借助水平线圈传感器观测垂直分量磁场信号.然而,在实际探测过程中,观测单一分量磁场信号不仅缺失水平分量磁场信息,并且在磁场响应畸变区域难以校正,造成视电阻率解释结果精度低、误差大等问题.为此,本文设计并研制了一种能够用于SAFEM探测的三分量空心线圈传感器,采用三组相互垂直的接收线圈分别接收三个分量的磁场信号.首先,为满足旋翼机载重要求,设计0.5 m直径的小尺寸圆形线圈用于接收垂直方向磁场,两个0.01 m边长的方形线圈用于接收水平方向磁场,并对三组线圈的互耦情况进行分析,确定了线圈的最佳相对位置.其次,针对线圈传感器的物理结构特点,综合线圈的寄生电阻、电感和电容值大小的分析结果,确定最终的物理结构参数.进一步地,通过分析不同阻尼状态下的传感器及前置放大电路的频率响应特性,确定了最佳的阻尼系数调节范围.在此基础上,设计了带有阻尼状态调节的低噪声差分前置放大器电路作为SAFEM信号调理模块.最后,开展屏蔽室测试实验和野外探测实验验证三分量线圈传感器的可靠性.屏蔽室内对比测试结果表明,小尺寸的三分量线圈传感器带宽能够满足探测需求,能够提供与商用传感器相当的灵敏度和测量准确性.在野外探测实验中,使用该三分量线圈传感器获得了实验场地的三分量磁场响应信号,进一步证明了该三分量传感器的有效性.Semi-airborne frequency domain electromagnetic method(SAFEM)usually uses a horizontal coil to observe the signal of the magnetic field in the vertical component.However,in the actual detection process,the signal not only lacks the information of horizontal component magnetic field,but also it is difficult to correct the signal amplitude in the distortion area of the magnetic field,which results in low accuracy and large error of apparent resistivity interpretation.In this paper,a three-component coil sensor for SAFEM detection is researched and designed,which consists of three groups of mutually perpendicular receiving coils to receive three-component magnetic field signals.Firstly,in order to meet the load requirements of the rotorcraft,a small circular coil with the diameter of 0.5 m is designed to receive the signal of the magnetic field in the vertical component,and two square coils with the side length of 0.01 m are designed to receive the signal of the magnetic field in the horizontal component,and the mutual coupling of the three groups of coils is analyzed to optimize the relative position of the coils.Secondly,according to the physical structure characteristics of the coil sensor,the final physical structure parameters are determined by synthesizing the analysis results of the parasitic resistance,inductance,and capacitance of the coil sensor.Further,by analyzing the frequency response characteristics of sensors and preamplifiers under different damping states,the optimal damping coefficient adjustment range is determined.On this basis,a low-noise differential preamplifier circuit with damping state adjustment is designed as the SAFEM signal conditioning module.Finally,the reliability of the three-component coil sensor is verified by conducting the test in shielding room and field detection experiments.The results show that the small size of the three-component coil sensor can meet the detection requirements,and can provide sensitivity and measurement accuracy comparable to commercial sensors.In the fiel

关 键 词：半航空电磁探测 三分量传感器 线圈互耦分析 阻尼电路设计 

分 类 号：P631[天文地球—地质矿产勘探]