CAJ | 학술논문

乙烷是电力变压器油中溶解的主要故障特征气体之一，其高精度、高灵敏度检测是进行油中溶解气体分析的关键。基于光反馈原理及腔增强吸收光谱技术，结合量子级联激光器，建立了一套变压器油中溶解乙烷气体检测系统。基于腔内单腔模对称理论，通过LabVIEW编程来实现反馈光与腔谐振的相位匹配。研究并实现了光学反馈效应（激光将在延迟一定的时间后，返回激光腔并锁定腔模式共振频率）、偶数和奇数模式效应（交替出现强度较大和较小的腔模式）、激光器阈值电流降低效应（约1.2 mA）。利用腔衰荡光谱检测技术测得的系统有效反射率、腔品质因素分别为99.978％和7138.4，系统光谱分辨率达到0.0052 cm －1。标准大气压、温度20℃下，1 s的积分时间内，对乙烷P Q3吸收线进行检测，系统检测准确率及检测极限分别达到95.72％±0.17％和（1.97±0.06）×10－3μL?L －1，满足了变压器油中溶解乙烷气体检测的需要。
을완시전력변압기유중용해적주요고장특정기체지일，기고정도、고령민도검측시진행유중용해기체분석적관건。기우광반궤원리급강증강흡수광보기술，결합양자급련격광기，건립료일투변압기유중용해을완기체검측계통。기우강내단강모대칭이론，통과LabVIEW편정래실현반궤광여강해진적상위필배。연구병실현료광학반궤효응（격광장재연지일정적시간후，반회격광강병쇄정강모식공진빈솔）、우수화기수모식효응（교체출현강도교대화교소적강모식）、격광기역치전류강저효응（약1.2 mA）。이용강쇠탕광보검측기술측득적계통유효반사솔、강품질인소분별위99.978％화7138.4，계통광보분변솔체도0.0052 cm －1。표준대기압、온도20℃하，1 s적적분시간내，대을완P Q3흡수선진행검측，계통검측준학솔급검측겁한분별체도95.72％±0.17％화（1.97±0.06）×10－3μL?L －1，만족료변압기유중용해을완기체검측적수요。
Ethane is one of major fault characteristic gases dissolved in power transformer ,the detection of Ethane with high ac‐curacy and sensitivity is the key of dissolved gas analysis .In this paper ,based on optical feedback theory and cavity‐enhanced ab‐sorption spectroscopy ,combined with quantum cascade laser ,a detection system for dissolved gas C2 H6 in transformer oil was built up .Based on the symmetry of the individual cavity modes ,the phase matching of returning light in resonance with the cavi‐ty was achieved through LabVIEW codes .The optical feedback effect that the emitted light return to the laser cavity after a small delay time and lock to the resonance frequency of cavity ,even and odd modes effect that the higher modes and lower modes structure will build up alternatively ,and threshold current lowering effect of about 1.2 mA were studied and achieved .By cavity ring‐down spectroscopy ,the effective reflectivity of 99.978% and cavity finesse of 7 138.4 is obtained respectively .The fre‐quency selectivity is 0.005 2 cm-1 .With an acquisition time of 1s ,this optical system allows detection for the P Q3 band of C2 H6 with high accuracy of 95.72% ± 0.17% and detection limit of (1.97 ± 0.06) × 10-3 μL?L -1 at atmospheric pressure and tem‐perature of 20 ℃ ,which lays a foundation for fault diagnose from dissolved gas analysis .