一种矢量梯度磁强计标准装置设计

Design of a Standard Device for Vector Gradient Magnetometer

作为弱磁场探测的重要手段,磁强计在国防军工、地球物理探测等领域的应用范围越来越广,目前水下磁探、航空磁探等都是通过测量梯度磁场对异常点进行判断及定位,因此梯度磁场测量的准确度、灵敏度直接影响结果的准确性。本文介绍了一种组合式的矢量梯度磁场标准装置,复现标准的梯度磁场及均匀磁场,可对梯度磁强计的准确度进行校准。该装置主要由均匀磁场复现系统和二维梯度磁场复现系统组成,可在方向可控、大小可调的均匀背景磁场基础上叠加梯度磁场,完整复现梯度磁强计工作过程中的背景磁场。其中均匀背景磁场复现范围20μT~100μT,梯度磁场复现范围10μT/m~100μT/m,测量不确定度1.2×10^(-3)B_(r)+1.4nT/m(k=2)。

As an important means of weak magnetic field detection,magnetometers have been widely used in fields such as national defense,military industry,geophysical detection,and so on.At present,underwater magnetic surveys and aerial magnetic surveys use gradient magnetic fields to judge and determine abnormal points.Positioning,therefore,the accuracy and sensitivity of gradient magnetic field measurement directly affect the accuracy of the result.This article introduces a combined vector gradient magnetic field standard device,which reproduces the standard gradient magnetic field and uniform magnetic field,and can calibrate the accuracy of the gradient magnetometer.The device is mainly composed of a uniform magnetic field reproduction system and a two-dimensional gradient magnetic field reproduction system,which can superimpose a gradient magnetic field on the basis of a uniform background magnetic field with a controllable direction and an adjustable size to fully reproduce the background of the gradient magnetometer in the working process magnetic field.The uniform background magnetic field ranges from 20μT to 100μT,and the gradient magnetic field ranges from 10μT/m to 100μT/m,The measurement uncertainty is 1.2×10^(-3) B_(r)+1.4 nT/m(k=2).