一种优化的精密温度测量方法

作者：张烂熳 日期：2009-11-16/span> 浏览：3883 查看PDF文档

一种优化的精密温度测量方法

张烂熳
（厦门神速信息通讯技术有限公司，福建 厦门 361006）

摘要：为了精密测量水蒸汽的温度，选择了Pt100测温铂电阻，并根据其非线性特性，提出了一种恒流源加电压频率（VF）转化器电路的优化测量方法。首先，采用1 mA的恒流源，保证流过铂电阻的电流恒定而且足够小，使电阻两端的电压差与电阻值成线性输出关系；其次，采用差分三运放放大电路，将电压信号按比例放大；然后，采用精密的电压频率转化器，将频率送给微处理器；最后，通过微处理器的采集频率以及简单的软件补偿，得到精密的温度值。试验结果表明，该方法能精密、方便、简单地采集与校准温度。
关键词：Pt100铂电阻；温度测量；非线性
中图分类号：TP212.11文献标识码：A文章编号：1001-4551(2009)09-0057-04

An optimized method of precision temperature measurement
ZHANG Lanman
(Xiamen Comtek Co. Ltd., Xiamen 361006, China)
Abstract: In order to measure the temperature accurately, the Pt100 platinum resistance was choosen, and according its nonlinear properties, an optimized measurement method that using constant current source and voltagetofrequency converters was developed. Firsly, the 1 mA constant current source was used, in order to ensure the flow of current platinum resistance constant and small enough. Secondly, three op amp differential amplifier circuit was used to enlarge the voltage signal proportionally. Then, the precision voltagetofrequency converter was used to send the frequency to microprocessor. Finally, by means of the collection frequency of microprocessor and simple software compensation, precision temperature was obtained. The test results show that this method can collect and calibrate the temperature accurately, conveniently and simply.
Key words: Pt100 platinum resistance; temperature measurement; nonlinear
参考文献(References):
［1］Freescale Semiconductor飞思卡尔半导体公司. HCS12 Microcontrollers MC9S12C Family［EB/OL］. ［2007-01-23］. http://www.freescale.com/files/microcontrollers/doc/data_sheet/MC9S12C128V1.pdf?fsrch=1.
［2］胡凤忠,彭炫.测温铂电阻的非线性特性及线性化处理［J］.矿业研究与开发,1995,15(3):45-48.
［3］国家质量技术监督局.JJG 229-1998工业铂、铜热电阻［S］.国家质量技术监督局，1998.
［4］王传旭.石油倾点温度测试Pt100温度传感器的标定［J］.传感器世界,2004,10(9):28-30.
［5］常健生.检测与转换技术［M］.机械工业出版社，1999.
［6］朱宇光.单片机应用新技术［M］.电子工业出版社，2001.
［7］National Semiconductor美国国家半导体公司. Precision VoltagetoFrequency Converters［EB/OL］. ［2006-04-26］. http://www.national.com/mpf/LM/LM331.html.