一种高灵敏度快速CO2/水汽分析仪设计

摘要

CO2和水汽通量是全球碳循环和水循环的重要特征参数,而碳水通量测量难点在于需要精度高、频率响应快的气体传感器.基于DSP与CPLD作为核心控制与处理模块,设计了一种非分光红外CO2/水汽分析仪.通过与标准气体对比,CO2相对偏差为1.638 mg/m3,精度可达到1×10-6;水汽相对偏差为5.39 mg/m3,精度可达10 ×10-6.同时,与商业仪器进行了对比测量实验,气体浓度值基本一致,结果表明:该仪器能够准确测定CO2,水汽浓度.%CO2 and water vapor flux is an important characteristic parameters of global carbon cycle and water cycle. The difficulty of measuring CO2 and water vapor flux is the need of high precision, fast frequency response gas sensor. A non-dispersive infrared CO2/water vapor analyzer , based on DSP and CPLD as the core control and processing module, is developed. Compared with standard gas, relative deviation of CO2 is 1. 638 mg/m3 , the precision can reach 1 × 10-6 ; relative deviation of water vapor is 5. 39 mg/m3 ,the precision can reach 10 ×10-6. By comparative experiment, the concentration is consistent with commercial instruments. The result shows that the CO2/water vapor analyzer can accurately measure CO2 and water vapor concentration.