作者：庞磊, 杨录, 郝建亮

作者单位：中北大学电子测试技术国家重点实验室, 山西 太原 030051

关键词：微量水分检测; 电容式传感器; 电桥平衡电路; 数据采集与处理

摘要：

针对在线检测火药含水量的实际要求,设计平板电容水分检测传感器,利用水的相对介电常数远大于被检物料的相对介电常数的原理,构建和电容传感器相关的交流电桥和测量电路,并设计自补偿电路,使得桥路输入为零时输出也为零。由于所测含水量范围为0.5%~3.5%,测量准确度为0.1%,为提高系统的测量准确度,分别对影响含水量的温度、湿度和重量容积比加以考虑,建立多参数校正的水分在线检测系统。经过大量实验验证:该系统性能稳定,测量精度高,具有很好的实用价值。

Design of capacitive micro moisture detection system

PANG Lei, YANG Lu, HAO Jian-liang

National Key Laboratory for Electronic Measurement Technology, North University of China, Taiyuan 030051, China

Abstract: Against the actual requirements of online testing the moisture content of gunpowder, the authors designed a tablet capacitive moisture sensor with the principle that the relative dielectric constant of water is much greater than the relative permittivity of the material, constructed an AC bridge measuring circuit associated with capacitive sensors, and designed the compensation circuit to make the bridge output be zero when the input is zero. Due to the measured moisture content ranging from 0.5% to 3.5%, the measurement accuracy was 0.1%. In order to improve the measure accuracy of the system, temperature, humidity and volume weight ratio, which may affect the measurement moisture content, were taken into consideration respectively. A multi-parameter correction was established for online water detection system. The stability and the high accuracy of the system were verified, and a lot of experiments also indicated that it has good practical value.

Keywords: moisture detection; capacitive sensors; bridge balance circuit; data acquisition and processing

2014, 40(4): 90-93  收稿日期: 2013-7-11;收到修改稿日期: 2013-9-17

基金项目: 

作者简介: 庞磊(1987-),男,山西忻州市人,硕士研究生,专业方向为测试技术计量与仪器。

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