光子学报, 2017, 46 (6): 0612002, 网络出版: 2017-06-27   

光声光谱技术在多组分气体浓度探测中的应用

Application of Photoacoustic Spectroscopy in Multi-component Gas Concentration Detection
作者单位
1 中国科学院安徽光学精密机械研究所,合肥,230031
2 中国科学技术大学,合肥,230031
摘要
CO和CH4气体作为判断变压器运行状态的故障气体,对其浓度的探测在变压器维护中具有重要意义.为了准确探测变压器运行过程中产生的CH4和CO气体浓度,本文利用光声光谱技术,设计了一套基于宽带光源的多组分气体探测系统,和共振型光声系统相比,该系统中所用的非共振型光声池体积小,易加工,池内各处信号强度相同,降低了对声学信号探测器的安装要求.系统的性能通过对CO和CH4气体的探测进行评估.首先,从理论上分析了信号强度与调制频率呈反比,然后根据宽带光声系统在不同调制频率下的响应,确定系统的最佳调制频率为22 Hz.在最佳调制频率下,根据温度与待测气体光声信号的关系,对光声信号进行温度补偿,消除温度变化对光声信号的影响,进一步提高了系统的稳定性.最后,通过不同浓度的CH4和CO气体对系统进行标定.实验表明,温度补偿前后,光声信号随温度的漂移分别为0.023 23V/℃和 8.383 48×10-5 V/℃,通过对不同浓度CH4和CO气体的探测,系统的线性度分别达到 0.995和0.998 4.在一个大气压下,积分时间为1s时,宽带光声探测系统对CO和CH4气体的探测极限浓度能够达到1μL/L.该系统成本低,线性度好,探测灵敏度符合国标对变压器维护过程中CO和CH4气体的探测要求.
Abstract
CO and CH4 as the fault gases in transformer, the detection of their concentration has important significant in transformer maintenance. In order to detect CH4 and CO gas concentration in transformer accurately, a photoaoustic spectroscopy multi-component gas detection system based on broadband thermal radiation light source has been developed. Compared to resonant photoacoustic cell based photoacoustic detection system, the non resonant photoacoustic cell used in the system has the advantage of small volume, easy to processed, high sensitivity and the intensity of signal is the same everywhere in non-resonant photoacoustic cell, thus reduce the requirements for the installation of the detector. The performance of the system was evaluated by detection of CH4 and CO. First, the relationship of the intensity of photoacoustic signal in non resonant photoacoustic cell between the radius and the modulation frequency was simulated by theoretical, it is illustrated that the signal enhanced with the reduction of the radius and the modulation frequency. Then the optimum modulation frequency of the system was determined as 22 Hz by the response of the system under different modulation frequencies. The function relations of photoacoustic signal and the temperature were studied, then the photocoustic signal was corrected by temperature compensate based on the function of signal and gas temperature under optimum modulation frequency to eliminate the impaction of temperature to photoacoustic signal, the stability of the system was improved after temperature compensate. The drift of the signal to temperature is 0.023 23V/℃ and 8.383 48×10-5 V/℃ respectively before and after temperature compensate. At last, the system was calibrated by different concentrations of CH4 and CO gas, the experiment show that the photoacoustic signal increased with the increasing of gas concentration and the linearity can reach to 0.995 and 0.998 4 respectively for the detection of different concentrations of CH4 and CO gas. The multi-component gas detection system based on broadband photoacoustic spectroscopy has the sensitivity of 1μL/L for CO and CH4 detection under atmospheric pressure with the 1s integration time. The developed system has low cost, good linearity and the sensitivity conform to the requirement of national standard in the process of transformer maintenance.

查申龙, 刘锟, 谈图, 王贵师, 高晓明. 光声光谱技术在多组分气体浓度探测中的应用[J]. 光子学报, 2017, 46(6): 0612002. ZHA Shen-long, LIU Kun, TAN Tu, WANG Gui-shi, GAO Xiao-ming. Application of Photoacoustic Spectroscopy in Multi-component Gas Concentration Detection[J]. ACTA PHOTONICA SINICA, 2017, 46(6): 0612002.

本文已被 9 篇论文引用
被引统计数据来源于中国光学期刊网
引用该论文: TXT   |   EndNote

相关论文

加载中...

关于本站 Cookie 的使用提示

中国光学期刊网使用基于 cookie 的技术来更好地为您提供各项服务,点击此处了解我们的隐私策略。 如您需继续使用本网站,请您授权我们使用本地 cookie 来保存部分信息。
全站搜索
您最值得信赖的光电行业旗舰网络服务平台!