提高甲烷气体探测器抗干扰能力的研究

Study on Improving Anti-interference Ability of CH_4 Detector

介绍了利用新型AVR单片机Mega128提高矿用甲烷气体探测器抗干扰能力的方法。探测器采用红外甲烷气体传感器IR12GJ将甲烷浓度转换为电信号,经由OP297组成的精密放大器后,输入到Mega128进行A/D转换与数字滤波。数字滤波包括限幅滤波、中值滤波和FIR低通滤波3个环节。限幅滤波与中值滤波用来滤除随机脉冲干扰。FIR低通滤波用来滤除周期性高频干扰,并针对生产现场最常见的工频干扰进行了特别设计,提高了其抗工频干扰的能力。从而提高了探测器的抗干扰能力。

This paper introduced the method to improve the anti-interference ability of CH4 detector designed for ore utility by using new type AVR microprocessor Mega128. The detector used infrared CH4 sensor IR12GJ to transform CH4 density signal into electric signal, after being amplified by an accurate amplifier whose kernel component was OP297, the analog electric signal was put into Mega128 to be translated into digital signal and filter the influence of disturbance by software. The software filtering included three steps, limit filtering, median filtering and FIR low-pas filtering. The first two steps can remove the influence of random fluctua- tion. The last step can remove the influence of periodic high-frequency interference, and the FIR low-passs filter was designed for the purpose of removing more effectively the power line interference, which is the mostly common interference in the industry field. Thus the detector can obtain high anti-interference ability.