铂电阻线性化和抗干扰测温模块的研究  

Research in Linearization and Anti-interference for Temperature Measurement Module with Platinum Resistance

作　　者：张传民[1] 甄国涌[1] 齐蕾[1] 姚宗[1] 

机构地区：[1]中北大学仪器科学与动态测试教育部重点实验室电子测试技术国家重点实验室,太原030051

出　　处：《自动化与仪表》2014年第10期72-76,共5页Automation & Instrumentation

摘　　要：该文从铂电阻温度传感器Pt100的电阻—温度特性方面分析了其非线性的原因,利用位于现场端的XTR105电流变送器对铂电阻输出信号进行调理并通过正反馈补偿其非线性后,输出工业标准的（4～20）mA电流至监控系统接收端的电流环接收器RCV420进行线性电流-电压转换.此外,还针对工业现场应用中出现的强射频干扰导致测温模块直流输出失调而引起测温误差问题进行了分析,并采用滤波电路滤除射频干扰.实验结果表明,该测温模块能通过一系列电磁兼容性测试,可以满足大部分工业现场应用要求,定标后测量误差不大于0.5 ℃.This paper analysises the reason of nonlinearity of the RTD temperature sensor for Ptl00 from resistancetemperature characteristics .Using the current transmitter of XTR105,which is located on-site end,to adjust the output signal of the RTD and compensate its nonlinearity through positive feedback.After that,Output a industry standard current of 4-20 mA to the current loop receiver of RCV420 located on monitoring system side for linear conversion of current-voltage.Besides and analyses the problem of thermometry error,which is derived from DC output offset because of strong RF interference appeared in industrial field applications,and using a filter circuit to filtrate this interference in the paper. Experimental results show that the temperature measurement module can pass a series of EMC tests,which meets the requirements of most industrial field applications.After calibration,the measurement error of the module is less than 0.5℃.

关 键 词：铂电阻温度传感器 XTR105 电流环 射频干扰 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]