基于自动平衡电桥的便携式阻抗测量仪设计  

A Portable Apparatus for Measuring Impedance Based on the Automatic Balance Bridge

作　　者：储开斌[1] 江楠 朱栋 CHU Kaibin;JIANG Nan;ZHU Dong(School of Microelectronics and Control Engineering,Changzhou University,Changzhou 213164,China)

机构地区：[1]常州大学微电子与控制工程学院,江苏常州213164

出　　处：《常州大学学报（自然科学版）》2020年第6期69-75,共7页Journal of Changzhou University：Natural Science Edition

基　　金：国家自然科学基金资助项目(61772090);江苏省重大成果转化资助项目(BA2017012)。

摘　　要：针对传统便携式阻抗测量仪精度不高的弊端,设计了一个基于自动平衡电桥的便携式阻抗测量仪。该测量仪采用将方波信号经滤波后得到测试信号源,应用高输入阻抗运算放大器组成I/V转换电路,实现对被测件电流的精确测量,通过脉冲鉴相电路对被测件两端电压及被测件中电流信号进行鉴相,得到电压和电流信号的幅度及初相角,再经单片机系统计算出被测件的阻抗参数。实验结果表明,该阻抗测试仪在对电阻及阻容串联网络进行测量时,其最大误差仅为0.052%,具有较高的测量精度。Due to low accuracy of the traditional impedance admeasuring apparatus,a portable impedance admeasuring apparatus based on an automatic balance bridge is designed.In the apparatus,a test signal source is obtained by filtering a square wave signal and an I/V conversion circuit is constructed by using a high input-impedance operational amplifier,which leads to accurately measuring the current via a tested unit.After amplitude and initial phase angle of both voltage and current signals of the tested unit are acquired by using the pulse phase discriminating circuit,the impedance parameters of the tested unit are calculated in the single-chip microcomputer system.The experimental results demonstrate that the impedance admeasuring apparatus is of high accuracy and its maximum error is only 0.052%when measuring resistors or resistance-capacitance series-connection networks.

关 键 词：自动平衡电桥 阻抗测量 脉冲鉴相 

分 类 号：TM930[电气工程—电力电子与电力传动]