基于磁通门原理的零磁通交直流电流传感器

摘要

文中基于磁通门技术和零磁通原理研究了一种交直流传感器.其利用聚磁环将一二次电流产生的磁场聚集并叠加,通过嵌入在聚磁环内部的高灵敏度磁通门传感器进行磁场检测,再通过高增益高带宽的功率放大电路输出,形成与一次电流相对应的二次电流.一、二次电流在聚磁环中产生大小相等、方向相反的磁场,最终能使聚磁环中的磁场为零,一、二次电流安匝数相等.同时,采用两个对称分布在聚磁环两边的磁通门传感器,提高系统对外界磁场的抗干扰能力.文章对传感器进行了交流误差、直流误差、阶跃响应、频率特性等试验测试,结果表明其在交直流下均满足0.01级要求.%In this paper,an AC / DC sensor is developed based on fluxgate technology and zero flux principle.The magnetic field generated by the primary and secondary current is gathered and superimposed by the poly-magnetic ring.The magnetic field is detected by a high-sensitivity fluxgate sensor embedded in the polygonal ring,and then,outputted through a high-gain and high-bandwidth power amplifier circuit.Thereby,a secondary current corresponding to the primary current is produced.The magnetic fields,generated by primary current and secondary current,are equal in value and opposite in direction.Ultimately,the magnetic field in the magnetic ring is zero,and the ampereturns of primary current and secondary current are equal.Two fluxgate sensors are symmetrically distributed on both sides of the magnetic ring to improve the anti-interference ability of the system to the external magnetic field.Test results of AC error,DC error,step response and frequency characteristic experiments show that the AC-DC current sensor is better than class 0.01.