摘要
针对配置气体动态稀释比的气体校准仪中,温度的变化会影响气体的密度,从而影响它们通过质量流量控制器的质量流量,若不能实时采集温度稀释比会有较大的误差。本文利用四线制温度传感器PT100、外部激励恒流源、抗混叠滤波电路、24位Δ-ΣADC组成的系统来测量气体室内的温度,恒流源激励PT100将温度信号转换为电压信号,然后通过Δ-ΣADC转换为数字信号,最后通过主控芯片FPGA进行数据采集并存储在Nor Flash芯片中。实测实验表明设计的系统测温分辨率可达0.05℃,重复性好,并且解决了引线电阻、自热效应、温度测量范围小的问题,具有一定的工程应用价值。
For the gas calibrator with dynamic dilution ratio of gas, the change of temperature will affect the density of gas, thus affecting the mass flow rate through the mass flow controller. If the temperature dilution ratio cannot be collected in real time, there will be a large error. In this paper, a four-wire temperature sensor PT100, an external excitation constant-current source, an anti-mixing filter circuit and a 24-bit DELta-sigma ADC are used to measure the temperature in a gas chamber. The constant-current source excitation PT100 converts the temperature signal into a voltage signal, and then into a digital signal through the delta-sigma ADC. Finally, the data is collected by FPGA and stored in Nor Flash chip. The experimental results show that the temperature resolution of the designed system can reach 0.05 ℃, the repeatability is good, and the problems of lead resistance, self-heating effect and small temperature measurement range are solved, which has certain engineering application value.
作者
邢震震
苏淑靖
梁文科
梁东飞
郭杨盛
Xing Zhenzhen;Su Shujing;Liang Wenke;Liang Dongfei;Guo Yangsheng(State Key Laboratory of Dynamic Measurement Technology,North University of China,Taiyuan 030051,China)
出处
《电子测量技术》
北大核心
2022年第8期21-26,共6页
Electronic Measurement Technology
基金
国家自然科学基金(51875534)
山西省“1331工程”重点学科建设项目资助。
