用于机动车尾气检测的NDIR传感器的加权定标方法研究  

Weighted Calibration Method of NDIR Sensor for Vehicle Exhaust Testing

作　　者：陈晨[1] 张玉钧[1] 何莹[1] 尤坤[1] 高彦伟[1] 刘国华[1] 

机构地区：[1]中国科学院安徽光学精密机械研究所中国科学院环境光学与技术重点实验室,安徽合肥230031

出　　处：《大气与环境光学学报》2016年第6期442-447,共6页Journal of Atmospheric and Environmental Optics

基　　金：国家863计划;2014AA06A503;国家重大科学仪器设备开发专项;2012YQ22011902~~

摘　　要：非分散红外(NDIR)气体传感器是机动车尾气CO和CO_2检测系统的核心部件,一般使用定标的方法来计算待测气体的浓度,针对传统定标方法生成的定标曲线在低于CO和CO_2满量程10%范围内拟合优度不能满足实际使用要求的问题,提出了一种基于最小二乘加权拟合法的定标方法,通过对低浓度点赋予更大的权重和增加定标点的数目来改善定标曲线在低浓度范围内的拟合优度.采用该方法的定标结果表明,定标曲线在整个量程范围内的定标误差均小于2%.所提出的定标方法具有较高的应用价值.Nondispersive infrared （NDIR） gas sensor is the key component of vehicle exhaust testing system for CO and CO2, and the concentration of measured gas always is calculated by calibration method. The calibration curve generated by traditional calibration method can not fit very well when the gas concentration is lower than 10% of full scale and can not satisfy the measurement requirement. For this problem, a new calibration method based on weighted least square fit is presented. The method can improve the goodness of fit by giving bigger weight to data point at lower concentration and increasing the number of calibration points. The calibration result shows that the calibration curve generated by this method has relative error lower than 2% in the entire measuring scale. The calibration method presented is important in practical application.

关 键 词：非分散红外气体传感器 定标方法 最小二乘加权拟合 

分 类 号：X831[环境科学与工程—环境工程] TP212.9[自动化与计算机技术—检测技术与自动化装置]