非分光红外甲烷传感器的研制

Development of non-dispersive infrared metheane gas transducer

矿用红外瓦斯传感器技术的难题是探测器输出信号微弱,光源电源波动、温度变化以及其它气体组分、水汽、灰尘等的干扰对测量精度会造成较大的影响.针对这些关键问题,讨论了数字化窄带滤波、双波长非分光测定技术等解决方案和相应的矿用传感器电路结构,提出了基于朗伯比尔定律的温度补偿方法.经试验测试,传感器的研制实现了预期的目标.测量精度优于±0.1%,响应时间小于20 s,其它技术指标和功能均符合矿用标准.

Under the circumstances of coal mining applications, one of the problems on metheane gas sensor technique based on infrared absorption is how to eliminate the bad measurement accuracy due to infrared source power supply jitter, thermal radiation, and interference of other gas, water vapor, coal dust etc.. Also, extremely small output singals for infrared detector was another defect of the method. So, a digital narrowband filter and a doublebeam non-dispersive infrared technique were discussed. Also, a new kind of transducer architecture and a thermal compensation method based on Lambert-Beer Law were proposed for coal mining applications. As a result, an infrared metheane transducer was developed successfully. Its measurement error is ＋ 0. 1%, and its respond time is less than 20 s. Its other features and functions all achieve the criterions for coal mining applications.