基于霍尔传感器阵列的电流测量系统

摘要

集磁环的存在导致开环式和闭环式霍尔效应传感器存在磁饱和现象.一种由多个霍尔元件构成圆形阵列方式的传感器阵列电流测量系统,通过测量一次导线产生的磁场计算得到被测电流数值克服了这一现象.首先建立霍尔传感器阵列数学模型,分析霍尔元件数量、载流体偏心引入的误差变化,然后设计加权增益调整电路、移相电路和基于电压反馈的功率放大电路,用于实现大功率信号输出,最后根据试验结果证明,所设计的电流测量系统整体准确度达到0.2级水平.该电流测量系统包含16个霍尔元件,检测电流变比为600 A/5 A,系统功耗仅0.4W.%Open-loop hall current transformer and closed-loop hall current transformer suffer the problem of magnetic saturation in the presence of magnetic core.A current measurement system based on Hall effect element array was developed,including the Hall effect sensor array and the electronic circuit.The circular array is composed of a surge of Hall element to approximate integration,and the measured current can be calculated by measuring the magnetic flux density induced by primary conductor.Firstly,the mathematic module of the array was formulated,and the error variation in the case of eccentric was investigated.Afterwards,the electronic circuit composed of the weighted gain adjustment circuit,the phase shift circuit and the power amplifier circuit were deigned to output high power signal.Finally,the basic error testing and the location influence experiment were performed.The results validate that the designed system can meet the requirement of 0.2 accuracy class.The designed system comprises 16 Hall elements,additionally,current ratio of the system is 600 A/5 A,while the power consumption is only 0.4 W.