基于自适应阻抗匹配技术的CSAMT电偶源高频大电流发射问题研究

The controlled source audio-frequency magnetotelluric (CSAMT) method is widely used in the exploration of the deep mineral resources and geological structure, et al, which plays an important role in the earth science research and the national economy construction. It is difficult to transmit the high-frequency large current in the inductive controlled source electromagnetic survey under the condition of long electric dipole, which becomes an unresolved problems of science and technology at home and abroad. This novel project is proposed. We want to implement large current high precision adjustable inductance by using the high precision servo motor to change the deep length of non-iron core in the circular cylindrical coil. We try to realize the adaptive impedance matching network concluded by the large current fine variable coupling capacitance and inductance. As a consequence, we provide the novel ideas to maximize the high-frequency output current in the transmission loop through the automatic fine matching, according to the monitoring of the change of the transmission current. The proposed adaptive impedance matching technology and the intelligent self-learning matching device are expected to solve the problem of high frequency large current transmission in the case of long electric dipole. The research will provide the powerful technology and instrument support for improving the resolution of deep electrical characteristics.

可控源音频大地电磁法（CSAMT）被广泛应用于深部矿产资源和地质构造的探测，在国民经济建设和地球科学研究中发挥着重要作用。然而，发射机在长电偶源极距的情况下，发射回路无法供出高频大电流，导致高频人工源信号还未传播至有效探测区域就已经衰减殆尽，这是国内外悬而未决的科学技术难题。本项目基于长期的积累和探索，创新性地提出：通过伺服电机高精度地改变非铁性环形磁芯深入环形线圈内的长度，实现大电流可变电感值的精细可调；利用可变电感和耦合电容，组成具备智能化自学习功能的阻抗匹配网络；根据发射电流的变化，基于谐振原理对发射回路负载进行自适应精细匹配，使得整体负载特性趋于纯阻性，最大化输出发射回路中的电流。拟研究的自适应阻抗匹配技术和研制的智能化自学习匹配装置，可彻底解决高频大电流发射问题，有效抑制环境干扰，提高远收发距实测数据的信噪比，为CSAMT方法增强地下电性特征的分辨能力提供有力的技术支撑。

可控源音频大地电磁法（CSAMT）被广泛应用于深部矿产资源和地质构造的探测，在国民经济建设和地球科学研究中发挥着重要作用。然而，发射机在长电偶源极距的情况下，由于长发射电缆中存在不可避免的较大感抗，发射回路无法供出高频大电流，导致高频人工源信号还未传播至有效探测区域就已经衰减殆尽，这是国内外悬而未决的科学技术难题。本项目基于长期的积累和探索，创新性地提出：通过电流控制型电感实现大电流可变电感值的精细可调；利用可变电感和耦合电容，基于串联谐振原理，组成具备智能化自学习功能的阻抗匹配网络；根据发射电流的变化，基于谐振原理对发射回路负载进行自适应精细匹配，使得整体负载特性趋于纯阻性，最大化输出发射回路中的电流。研究的自适应阻抗匹配技术和研制的智能化自学习匹配装置，彻底解决了高频大电流发射问题，有效抑制环境干扰，提高远收发距实测数据的信噪比，为CSAMT方法增强地下电性特征的分辨能力提供有力的技术支撑。