针对一氧化碳的检测问题，开发了基于TDLAS技术的一氧化碳浓度检测系统。通过原理分析，推导波长调制光束经气体吸收后二次谐波幅值与气体浓度之间的关系，使用一次谐波对二次谐波进行归一化处理，消除光强传输的影响。系统使用FPGA+MCU架构进行数据处理，在FPGA中进行二次谐波反演一氧化碳浓度的编程实现。检测系统搭建完成后，进行一氧化碳标准气测试实验，实验结果表明检测误差小于1 ppm，达到了实用水平。
According to the detection of carbon monoxide, a carbon monoxide concentration detection system based on TDLAS is developed. The relation between the second harmonic wave and carbon monoxide concentration is derived by analyzing the theory of TDLAS, and second harmonic is normalized by first harmonic to eliminate the influence of laser beam intensity. An algorithm of calculating carbon monoxide concentration by second harmonic is programmed in FPGA. Experiments of testing the system, after being assembled, by carbon monoxide of known concentration is implemented, and the result shows that the deviation between the carbon monoxide concentration and the data acquired by the system is less than 1 ppm, thus it can be used in practice.
2019,41(5): 134-137 收稿日期：2018-05-23
DOI：10.3404/j.issn.1672-7649.2019.05.028
分类号：X831
作者简介：顾利帅(1989-),男,硕士,助理工程师,研究方向为分析仪器开发
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