一种热电偶温度采集装置的优化设计  

An optimized design of the thermocouple temperature acquisition device

作　　者：王晨辉 赵冬青[1] 贾兴中[1] 陈建军[1] WANG Chenhui;ZHAO Dongqing;JIA Xingzhong;CHEN Jianjun(National Key Laboratory for Electronic Measurement Technology,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学电子测试技术国家重点实验室,山西太原030051

出　　处：《电子设计工程》2021年第6期44-48,共5页Electronic Design Engineering

摘　　要：温度在航天、工业、装备研发过程中是十分重要的一项参数,是影响设备正常工作的一项关键因素。为了解决K型热电偶易受冷端温度不稳定、空间电磁环境干扰、温度与热电势的非线性等因素导致的测量温度不准确问题,对热电偶温度采集装置进行了优化设计。通过使用一种冷端补偿仪表放大器,来消除冷端温度不稳定对测量造成的影响;以C8051F352单片机作为主控芯片温度模拟信号,将模拟信号通过内置ADC转换成数字信号发送至上位机进行非线性校正。测量结果表明,经过优化后的温度采集装置在-30~1 300℃范围内测量误差小于0.5℃,这种优化设计极大地提高了热电偶温度采集的精度。Temperature is a very important parameter in the aerospace,industrial,and equipment development process,and it is a key factor that affects the normal operation of equipment.In order to solve the inaccurate temperature measurement of K⁃type thermocouples due to the cold⁃end temperature instability,spatial electromagnetic environment interference and non⁃linearity of temperature and thermoelectric potential,the thermocouple temperature acquisition device was optimized.By using a cold⁃end compensation instrumentation amplifier,the influence of the cold⁃end temperature instability on the measurement is eliminated;the C8051F352 microcontroller is used as the main control chip temperature analog signal,and the analog signal is converted into a digital signal by the built⁃in ADC and sent to the upper computer for non⁃linear correction.The measurement results show that the optimized temperature acquisition device has a measurement error of less than 0.5℃in the range of-30℃to 1300℃.This optimized design greatly improves the accuracy of thermocouple temperature acquisition.

关 键 词：K型热电偶 温度采集 冷端补偿 C8051F352单片机 非线性校正 

分 类 号：TP274[自动化与计算机技术—检测技术与自动化装置]