基于AD7791的磁通门传感器数据采集与存储系统

Data Acquisition and Storage System of Magnetic Fluxgate Sensor Based on AD7791

摘要:

针对磁通门传感器检测到的多路弱磁信号,设计了一种以AD7791为采集核心的小信号采集系统,解决了6路AD采集的同步问题;以MSP430F5437超低功耗单片机为主控,运用无磁转台测试实验,实现了数据的存储和探头姿态的校正,后采用最小二乘法进行数据修正;经实rt验验证,该采集系统可稳定于野外长时间工作(半年以上),零点稳定度由1.7 nT/h、2.4 nT/h、1.4 nT/h(XYZ三轴)下降到0.2 nT/h、0.31 nT/h、0.23 nT/h,采集精度(参考地磁场49535nT)由49516nT下降到49534nT;有效地降低了系统测量误差,精度明显提高。

Abstract:

A small signal acquisition system based on AD7791 is designed to solve the multiple weak magnetic signals detected by the magnetic flux-gate sensor, which solves the problem of the synchronization of the six channel AD acquisition. MSP430F5437 ultra low power microcontroller act as based control, the use of non magnetic turntable test experiment, to achieve the data storage and probe attitude correction, and using the least square method for data correction. After experimental verification, the system can be stable in the field work for a long time (more than half year), zero stability by 1.7 nT/h, 2.4 nT/h, 1.4 nT/h (XYZ three axis) dropped to 0.2 nT/h, 0.31 nT/h, 0.23 nT/h, acquisition accuracy (reference field 49535nT) decreased from 49516nT to 49534nT. Effectively reduce the system measurement error, and the accuracy is obviously improved.