便携式非分光红外SF_6气体检测方法研究  

Research on method of portable NDIR SF_6 gas detection

作　　者：沈婉 常建华[1,2] 赵勇毅 赵正杰 裴昱[1] Shen Wan;Chang Jianhua;Zhao Yongyi;Zhao Zhengjie;Pei Yu(Collaborative Innovation Center of Atmospheric Environment and Equipment Technology,Nanjing University ofInformation Science ＆ Technology,Nanjing 210044,China;Jiangsu Key Laboratory ofMeteorological Observation and Information Processing,Nanjing University ofInformation Science ＆ Technology,Nanjing 210044,China)

机构地区：[1]南京信息工程大学江苏省大气环境与装备技术协同创新中心,江苏南京210044 [2]南京信息工程大学江苏省气象探测与信息处理重点实验室,江苏南京210044

出　　处：《应用光学》2018年第4期545-550,共6页Journal of Applied Optics

基　　金：国家自然科学基金(11374161);江苏省重点研发计划(BE2016756);江苏高校优势学科Ⅱ期建设工程;江苏省高校品牌专业建设工程资助项目;国家级大学生实践创新训练计划项目(201610300030;201710300015)

摘　　要：为了满足电力系统中对SF_6气体精确测量的需求,基于非分光红外差分检测原理,设计了一种便携式的SF_6气体传感器。系统采用单光束双波长结构,对直射式和梯形反射式气室进行光学仿真,最终确定了气室类型,提高了系统的紧凑性和灵敏度。在电路方面设计了一种小信号放大滤波电路,有效地将有用信号从噪声中提取出来;传感器采用高精度高性能模数转换器将模拟电信号转换为数字信号送入单片机处理,大大提高了检测精度。实验结果表明,该传感器能够准确检测体积分数为0~2×10-3范围内的SF_6气体,满量程精度可达4.2%。In order to satisfy the actual need of accurate measurement of SF6 gas concentration in the electrical system,aportable SF6 gas sensor was designed based on non-dispersive infrared（NDIR）differential detection principle,which adopted the single-beam and dual-wavelength optical structure.In order to improve the compactness and sensitivity of the system,the optical simulations of the straight and trapezoidal reflective gas chambers were carried out,and the gas chamber type was finally determined.As for designing hardware circuit,a small signal amplification filter circuit was designed to effectively extract the useful signal from the noise.The sensor uses the high precision and performance analog-to-digital converters to convert analog electrical signals into digital signals into single chip processor,which greatly improves the detection accuracy.The experimental results show the sensor can accurately measure the SF6 concentration in a range of 0～2×10～（-3）,with the full range accuracy up to 4.2%.

关 键 词：SF6气体 气室仿真 放大滤波 AD转换 

分 类 号：TN219[电子电信—物理电子学] TP219[自动化与计算机技术—检测技术与自动化装置]