针对井下智能导钻工程中使用的传统磁通门传感器不耐高温且在尺寸上无法满足井下狭小空间等问题,设计了工作在175℃高温环境下的高性能数字磁通门传感器.该传感器基于二次谐波法设计,采用SM320F28335GBS作为主控芯片,协调控制激励电路、感应电路、反馈电路与温度数据采集电路,联合磁通门探头实现了高温环境下磁场信号的采集与处理.实验测试结果表明:该高温磁通门传感器的量程为±60 000 nT,分辨率为3 nT,线性度为0.03%,与高性能磁通门磁测数据的相关系数为0.927,在175℃高温环境下的磁测数据验证了该数字磁通门样机能够用于高温环境下的磁场测量.
In view of the problems that the traditional fluxgate sensor used in downhole smart drilling project is not resistant to high temperature and its size can not meet the narrow space of the well,a high-performance digital fluxgate sensor was designed to work in the high temperature environment of 175℃.The sensor was designed based on the second harmonic method,using SM320F28335GBS as the main control chip,coordinating the control of the excitation circuit,sensing circuit,feedback circuit and temperature data acquisition circuit,and the joint fluxgate probe realized the acquisition and processing of magnetic field signals in high temperature environment.Experimental test results show that the high-temperature fluxgate sensor range is of±60 000 nT,resolution is of 3 nT,linearity is of 0.03%,and high-performance fluxgate magnetic measurement data correlation coefficient is of 0.927,magnetic measurement data in the 175℃high-temperature environment verifies the digital fluxgate prototype can be used for high-temperature environment of the magnetic field measurement.