关键词: 矢量梯度磁强计, 标准装置, 二维梯度磁场线圈

Abstract: 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 20 μT to 100 μT,and the gradient magnetic field ranges from 10 μT/m to 100 μT/m,The measurement uncertainty is 1.2×10^-3B_r+1.4 nT/m (k=2).

Key words: Vector gradient magnetometer, Standard device, Two dimensional gradient field coil