基于非晶丝低频磁阻抗效应的无圈磁通门传感器

Coil-less Fluxgate Sensor Based on Low-frequency Magneto-impedance Effect in Amorphous Wire

介绍了非晶丝低频磁阻抗效应的理论,并制作了实验装置。利用晶体振荡电路以及低通滤波器获得的正弦信号激励外加扭转应变的钴基非晶丝,对非晶丝两端的输出电压信号提取二次谐波分量,通过改变施加给非晶丝的扭转应变以及激励信号有效值的大小,测出了二次谐波电压随被测磁场之间的变化关系,确定了最佳扭转应变和最佳激励电流有效值,最后设计出了一种无圈磁通门传感器,该传感器在弱磁检测领域具有很好的应用前景。

The theory of low-frequency magneto-impedance effect in amorphous wires was presented,and the experimental configuration was designed.The twisted Co-4base amorphous wire was excitated by sinusoidal signal produced by a crystal oscillator circuit and a low-pass filer.The second harmonic of the output signal from the wire ends dependence of the applied magnetic field with various torsional strains and excitation current values was studied.The coil-less fluxgate sensor was made finally with optimal torsional strain and excitation current value,and has a good prospect in the field of weak magnetic measurement.