基于紫外光声光谱的SF_(6)特征分解组分SO_(2)的高灵敏度检测技术  

High Sensitivity Detection Technology of SF6 Characteristic Decomposition Component SO2 Based on UV Photoacoustic Spectroscopy

作　　者：马凤翔 赵跃 赵新瑜 王楠 朱太云 杭忱 陈珂 MA Fengxiang;ZHAO Yue;ZHAO Xinyu;WANG Nan;ZHU Taiyun;HANG Chen;CHEN Ke(Electric Power Research Institute,State Grid Anhui Electric Power Co.,Ltd.,Hefei 230601,China;School of Optoelectronic Engineering and Instrumentation Science,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]国网安徽省电力有限公司电力科学研究院,合肥230601 [2]大连理工大学光电工程与仪器科学学院,大连116024

出　　处：《光子学报》2023年第3期198-206,共9页Acta Photonica Sinica

基　　金：国家电网有限公司总部科技项目(No.B31205210011);国家自然科学基金(No.61905034)。

摘　　要：搭建了一套气室容积仅为0.79 mL的非共振式光声光谱检测装置,在0至100 ppm浓度范围内,激发的光声信号幅度与SO_(2)/SF_(6)混合气体浓度之间有良好的线性关系,响应度为5.59μV/ppm。系统的归一化噪声等效吸收系数为7.2×10^(-8)cm^(-1)W·Hz^(-1/2)。Allan-Werle方差分析结果表明,当平均时间为100 s时,系统对SO_(2)的检测极限达到0.1 ppm。本文提出的高灵敏度SO_(2)气体原位检测技术为判断SF_(6)气体绝缘设备的故障程度提供了有效的解决方案。SF_(6)gas is a chemically stable and non-toxic inert gas with excellent insulation and arc extinguishing properties.It is widely used as an insulating medium in high-voltage electrical equipment.SF_(6)decomposes under a strong electromagnetic field to produce a variety of low-fluorine sulfides and then chemically reacts with impurities such as trace H2O and O_(2)existing in the equipment to produce HF,SO_(2)F_(2),CO,CF_(4),H_(2)S,SO_(2)and other gases.The type and severity of faults inside the equipment are closely related to the type and content of SF_(6)decomposition products.SO_(2)gas is one of the important characteristic components of SF_(6)decomposition products,which can effectively reflect the severity of latent faults inside SF_(6)gas insulation equipment and is highly corrosive.The increase of SO_(2)content will aggravate metal surface corrosion and increase the degree of discharge.Therefore,real-time monitoring of trace SO_(2)concentration is an important means to ensure the safe and stable operation of power systems.Photoacoustic Spectroscopy(PAS)based on the Beer-Lambert absorption law has been applied in the detection of SF_(6)decomposition products due to its advantages of no carrier gas,high detection sensitivity,good selectivity and fast response speed.SO_(2)gas was excited to a high-energy state after absorbing a broad-spectrum light of 275 nm.The life of the high-energy state was extremely short.The modulated excitation light source caused the temperature in the Photoacoustic Cell(PAC)to change periodically,and the pressure inside the non-resonant PAC with good sealing changed accordingly,generating a Photoacoustic(PA)signal.The signal processing unit inverted the concentration information of the SO_(2)gas to be measured according to the amplitude of the PA signal detected by the acoustic sensor.A set of SO_(2)detection device based on ultraviolet PAS was built using a miniaturized non-resonant PAC with a gas chamber volume of only 0.79 mL,which realized the high-sensitivity detection of SO_(2)

关 键 词：气体绝缘设备 SF_(6)特征分解组分 微量气体检测 光声光谱 非共振式光声池 

分 类 号：O433.4[机械工程—光学工程]