电容式湿度传感器的设计  

Design of capacitive humidity sensor

作　　者：田海军[1] 薛家兴[1] 薛彦杰[2] TIAN Haijun;XUE Jiaxing;XUE Yanjie(School of Automation Engineering,Northeast Dianli University,Jilin 132012,China;Shenyang Entry-Exit Inspection and Quantine Bureau,Shenyang 110016,China)

机构地区：[1]东北电力大学自动化工程学院,吉林吉林132012 [2]沈阳出入境检验检疫局,辽宁沈阳110016

出　　处：《现代电子技术》2017年第14期128-131,共4页Modern Electronics Technique

基　　金：国家自然科学基金(61304015)

摘　　要：为了能够更好解决测量流动蒸汽湿度准确度低、难度大等问题,设计了一种电容式湿度传感器,其为同轴圆筒式多极电容传感器结构,利用电容数字转换技术芯片PCap01进行电容值的检测,通过SPI通信方式将测量结果传输到STM32单片机中进行处理,采用AD421将输出结果转换为标准的4~20 m A信号。实验结果表明,在一定温度下,随着产生湿度的变化,湿度与输出电流呈线性关系,当产生的湿度不变时,电流趋于稳定状态,该设计能够进行湿度的测量。A capacitive humidity sensor is designed for better solving the low accuracy and high difficulty existing in themoisture measurement of flowing steam,which is coaxial cylinder multipolar capacitance sensor structure,and in which the capacitance digital conversion technology chip PCap01is used to detect capacitance value.It transfers measured results to STM32microcontroller for data processing by SPI communication.AD421is adopted to convert the output results into standard signalsof4~20mA.The experimental results show that there is a linear relationship between the output current and the humidity withthe change of humidity at a certain temperature,and when the temperature is not changed,the output current goes to stability.

关 键 词：多极电容传感器 湿度测量 PCap01 电容检测 

分 类 号：TN641.2-34[电子电信—电路与系统] TP212.9[自动化与计算机技术—检测技术与自动化装置]