基于中红外激光器的腔增强光谱检测  

High-precision photoacoustic spectroscopy detection technology for acetylene based on mid-infrared quantum cascade laser

作　　者：冯玉辉 高超 郑昌军 FENG Yuhui;GAO Chao;ZHENG Changjun(China Nuclear Power Operations Co.,Ltd.,China General Nuclear Power Group,Shenzhen 518124,China;Wuhan Gainway Technology Co.,Ltd.,Wuhan 430000,China)

机构地区：[1]中广核集团中广核核电运营有限公司,深圳518124 [2]武汉敢为科技有限公司,武汉430000

出　　处：《国外电子测量技术》2025年第1期30-35,共6页Foreign Electronic Measurement Technology

摘　　要：为了满足变压器油中溶解气体中乙炔最低检测下限0.1μL/L的测量要求,提出一种基于中红外量子级联激光器(QCL)的腔增强光声光谱检测技术。通过对光声池的理论研究,提出通过增加反射次数,提高光声响应强度。双光束和四光束相对于单光束的理论光声强度分别高1.985倍和3.824倍,实际测量高1.84倍和3.59倍,实测值与理论值接近。基于四光束光声检测系统对乙炔气体进行了实际测试,系统的响应值与浓度成线性关系,线性相关系数达到0.999;通过氮气的长时间测试结果,最低检测下限的理论值达到0.01μL/L;进一步采用高精度配气机验证,该技术能达到0.05μL/L的最低检测限。To fulfill the measurement requirement of detecting acetylene in transformer oil dissolved gases with a minimum detection limit of 0.1μL/L,a study on cavity-enhanced photoacoustic spectroscopy based on mid-infrared quantum cascade lasers(QCLs)was conducted.Theoretical research on the photoacoustic cell suggested enhancing the photoacoustic response intensity by increasing the number of optical reflections.Simulations were performed and compared for single-beam,double-beam,and quadruple-beam photoacoustic responses,with the double-beam and quadruple-beam configurations yielding 1.985 and 3.824 times greater responses than the single-beam configuration,respectively.Experimental measurements confirmed these enhancements to be 1.84 and 3.59 times,respectively,aligning well with theoretical predictions and validating the theory.A quadruple-beam photoacoustic detection system was employed for actual acetylene gas testing,demonstrating a linear relationship between the system’s response and gas concentration with a correlation coefficient exceeding 0.999.Long-term testing with nitrogen gas and subsequent Allen variance analysis indicated a theoretical minimum detection limit of 0.01μL/L.Utilizing a high-precision gas diluter,the system’s capability to achieve a minimum detection limit of 0.05μL/L was verified.

关 键 词：中红外量子级联 乙炔 光声池 光谱检测 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]