Methane Detector Based on the Principle of NDIR

A methane gas sensor based on the principle of non-optical infrared method (NDIR) was proposed. And STM32F103C8T6 single chip microcomputer was used as the core controller. The sensor design includes hardware part and software part. The hardware design is mainly aimed at the core circuit of the sensor. The stable driving circuit of the light source can improve the stability of infrared light and provide over-voltage protection to the circuit. The signal conditioning circuit can amplify and filter the weak electrical signal from pyroelectric detector. The method of combining software and hardware is used to reduce the influence of noise interference. Finally, through a large number of experimental tests, the error analysis and compensation of the sensor are carried out. The experimental results show that the sensor has a high measurement accuracy and the relative error less than 2%, which can realize the function of real-time measurement of methane gas.