摘要
为了实时监控液氮罐温度,防止液氮过快汽化,设计了一款以四线制Pt100铂电阻为敏感元件,采用双运放构成的精密恒流源为驱动的液氮罐温度记录仪。采用双运放构成的精密恒流源可消除温漂等因数引起驱动电流的波动,同时使得Pt100输出电压与阻值有较好的线性关系。采用24位A/D转换器对信号采样,将采样数据传送给控制器进行数据处理,并利用SD卡以CSV格式保存数据和OLED显示液氮罐的温度。最后对液氮罐温度仪进行了模拟实验测试。结果表明:记录仪能够对液氮罐的温度进行实时检测、记录和存储,精度可达0.1℃,性能稳定可靠,也适用于其他电阻式传感器。
In order to monitor the temperature of a liquid nitrogen container in real-time and prevent the vaporization of liquid nitrogen,it is necessary to install a temperature-monitoring system with good stability and high accuracy.This paper proposes a liquid nitrogen containers temperature recorder with a four-wire Pt100 platinum resistance as the sensitive element,and it uses dual op amps to form a precision constant current source,which can eliminate the fluctuations in the driving circuit caused by temperature drift,while making the Pt100 output voltage and resistance have a good linear relationship.Using 24-bit A/D converter samples the signal,it transmits the sampled data to the controller for data processing and uses the SD card to save the data in CSV format,then displays the temperature of the liquid nitrogen containers on the OLED.This article designed and optimized the related circuit of this thermometer in detail,and designed the the related software.Finally,the temperature instrument of liquid nitrogen containers was tested in simulation experiments.The results show that the recorder can detect,record and store the temperature of the liquid nitrogen containers in real-time.The measurement precision of the recorder can up to 0.1℃,and its performance is stable and reliable.In addition,it’s also suitable for other types of resistance sensors.
作者
刘建生
杨超
LIU Jiansheng;YANG Chao(School of Electrical Engineering and Information,Southwest Petroleum University,Chengdu 610500,China)
出处
《实验室研究与探索》
CAS
北大核心
2021年第12期88-91,97,共5页
Research and Exploration In Laboratory
基金
国家青年基金项目(51607151)
四川省科技计划重点研发项目(2020YFG0182)资助。
关键词
液氮灌温度
铂电阻
恒流源
记录仪
temperature of liquid nitrogen tanks
platinum resistance
constant current source
recorder
