催化气体传感器的恒温检测方法及其在瓦斯检测中的应用

Constant Temperature Catalytic Gas Sensor Detection Method and Application In Gas Detection

可然性气体催化燃烧放热导致催化气体传感器的敏感元件温度升高,由于热耗散和化学反应速度(即催化燃烧的放热速率)与温度的非线性,使得传感器的输出与被测气体浓度(特别是在较高的检测浓度下)呈非线性。采用恒温检测方法,即采用输出反馈调节传感器工作电流以保持传感器温度恒定的检测方法可解决该问题,且可扩大检测浓度范围。对甲烷气体的实验结果表明:其线性浓度范围达到10%。

Quantiy of heat of combustible gas catalytic combustion causes temperature of sensor＇s sensitive element to increase. But heat dissipation and the chemical reaction speed（ heat release rate of catalytic combustion） are nonlinear vary with the sensor temperature, so the output of thermal catalytic gas sensors vary with measured gas concentration （ especially in the higher concentration detected gas）is non-linear. A constant temperature detection method was adopted, it output feedback of sensor, regu- late the working current to maintain constant temperature of sensor, and it expand the measured gas concentration range. The experi- mental result for methane shows its linear measured gas concentration achieves 10 percents.