针对普通气体传感器在低体积分数的气体检测中灵敏度低的问题,提出将待测气体进行压缩以增强气体传感器响应的方法,根据检测压缩后的气体响应的特征,间接得到普通状态下该气体的体积分数。设计了一种小型的样机系统来进行气体压缩和气体传感器检测,描述了系统各个模块的设计,给出了该系统的软件设计和控制流程。以H2S气体为检测对象进行了实验,分析结果表明:该方法提高了现有传感器检测低体积分数气体的能力,尤其是提高了对毒害气体的及时发现和预警防范能力。样机的试制也为该压缩传感系统的进一步小型化和提升检测性能提供了条件,具有较高的应用价值。
Aiming at problem of lower sensitivity in low volume fraction gas detecting of normal gas sensor, a measuring method which enhances gas sensing response by compressing target gas is proposed. According to sensing character of compressed gas, volume fraction of the target gas in ordinary sate is obtained. A set of small prototype system is designed for gas compressing and testing, design of each module of system are described, software design and control flowchart are presented. Experimental results of using H2 S as the target gas show this method improves the ability improve ability to detect lower volume fraction, especially improve ability to detect and alarm toxic gas. Fabrication and test of prototype system provide condition for device with higher performance and smaller size, and has high application value.