摘要
为实现在线监测粉尘浓度,设计了一个激光在线粉尘检测仪。在一个典型的烟尘排放连续监测(CEMS)系统中,激光粉尘检测距离要求达到15 m以上,然而半导体激光器的输出光功率在20 mW以下。为了从强噪声背景中提取极其微弱的反射光信号,设计了一种数字平均器以提取"nW"级别的微弱反射光信号。对原型机在不同测量距离和消光比条件下进行了性能测试。测试结果显示,使用数字平均器进行在线粉尘浓度检测,测量距离可以达到要求的15 m,同时测量线性度优于2%。
Aiming at monitoring dust concentration on-site,an on-site laser dust concentration monitor was designed.In a typical continuous emission monitoring system（CEMS）,measuring range of laser dust concentration monitor is up to 15 m,but the output optical power of LD is below 20 mW.To get the ultra-weak reflected light from strong noisy background,a digital averager was designed to refine ＂nW＂ level light signal.The performance of prototype was tested at different measuring range and different extinction.The results indicate that,using digital averager to detect dust concentration on-site,measuring range reaches desired 15 m and the linearity is better than 2%.
出处
《机电工程》
CAS
2011年第12期1453-1456,共4页
Journal of Mechanical & Electrical Engineering
关键词
激光透射式粉尘仪
粉尘浓度检测
弱信号检测
数字平均器
laser dust concentration monitor
dust concentration detection
weak signal detection
digital averager
