基于质量流量控制器的多组分动态配气系统研究

Research on the Dynamic Multiple Gases Distributing System Based on Mass Flow Controller

针对在对气体浓度监测系统进行标定时需要多种不同浓度值标准气的需求,对基于质量流量控制器的多组分动态配气系统进行了研究,设计并研制了配气系统样机。计算机通过USB接口与高精度的质量流量控制器通信,严格控制各组分气体流量,从而实现多组分动态配气。配制的标准气浓度可达10-9级,并且连续可调,稀释比达到1/2000,不确定度最小可达到0.8%。系统不受环境温度与压力变化影响,对配制高、低浓度的标准气都适合,具有很好的应用价值。

In calibrating gas concentration monitoring system, it is necessary to supply multiple standard gases with different concentrations. The dynamic multiple gases distributing system based on mass flow controller was researched ,and a prototype unit was built. The computer communicated with highly precise mass flow controller via USB interface, thus the gas flow of each kind of gases is under strict control. The concentration of the gases reaches 10^-9, and can be adjusted continuously. The dilution ratio is up to 1/2 000, and the minimum uncertainty up to 0. 8%. The system is not affected by ambient temperature or pressure,it is suitable for standard gases in both high and low concentration. It is valuable in practical applications.