摘要
在冶金、化工、环保各工业领域中,管道内特定气体浓度检测是工艺优化、安全生产、环保排放等工业过程的重要参考依据。激光分析仪具有原位式安装、响应时间快、维护简便等优点,是很多生产工艺不可或缺的气体浓度检测仪表。在光源驱动端完成光强的高频调制,光通过被待测气体被吸收后达到接收端,在接收端采用调制频率的倍频解调出对应的谐波,再由谐波信息计算气体浓度。由此通过可调谐半导体激光光谱吸收技术与谐波检测技术结合,气体检测精度会大幅提高。通过发射光调制和接收光解调完成了被吸收后光强的二次谐波提取,并通过标准气测试验证了系统的线性误差完全满足应用需求。
In the fields of metallurgy,chemical industry and environmental protection,the detection of specific gas con-centration in pipeline is an important reference for process optimization,safe production,environmental protection and other industrial processes.Laser gas analyzer has the advantages of in situ installation,quick response time,easy maintenance and so on.It is an indispensable instrument for gas concentration detection in many production processes.The high frequency mod-ulation of light intensity is completed at the driving end of the light source,and the light reaches the receiving end after being absorbed by the gas to be measured.At the receiving end,the corresponding harmonics are demodulated by the frequency multiplier of modulation frequency,and then the gas concentration is calculated by the harmonic information.Therefore,the precision of gas detection can be greatly improved by combining tunable semiconductor laser spectrum absorption technology with harmonic detection technology.The second harmonic of the absorbed light intensity was extracted by transmitting light modulation and receiving light demodulation,and the linear error of the system was verified by standard gas test to meet the application requirements.
作者
牛麒斌
王竞
龚德明
NIU Qibin;WANG YuJing;GONG Deming(Technical Center of Chongqing Chuanyi Automation Co.,Ltd.,Chongqing 401121,China)
出处
《自动化与仪器仪表》
2022年第10期267-269,共3页
Automation & Instrumentation
