Zhang Zhengyuan, Fan Xinhong, Xu Yufu, Wang Yongqi, Tang Yiyao, Zhao Rui, Li Chenxi, Wang Heng, Chen Ke
State Grid Gansu Electric Power Research Institute, Lanzhou 730030, China.
School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian 116024, China.
Sensors (Basel). 2023 Sep 3;23(17):7644. doi: 10.3390/s23177644.
A single-fiber photoacoustic (PA) sensor with a silicon cantilever beam for trace acetylene (CH) gas analysis was proposed. The miniature gas sensor mainly consisted of a microcantilever and a non-resonant PA cell for the real-time detection of acetylene gas. The gas diffused into the photoacoustic cell through the silicon cantilever beam gap. The volume of the PA cell in the sensor was about 14 μL. By using a 1 × 2 fiber optical coupler, a 1532.8 nm distributed feedback (DFB) laser and a white light interference demodulation module were connected to the single-fiber photoacoustic sensor. A silicon cantilever was utilized to improve the performance when detecting the PA signal. To eliminate the interference of the laser-reflected light, a part of the Fabry-Perot (F-P) interference spectrum was used for phase demodulation to achieve the highly sensitive detection of acetylene gas. The minimum detection limit (MDL) achieved was 0.2 ppm with 100 s averaging time. In addition, the calculated normalized noise equivalent absorption (NNEA) coefficient was 4.4 × 10 W·cm·Hz. The single-fiber photoacoustic sensor designed has great application prospects in the early warning of transformer faults.
提出了一种用于痕量乙炔（CH）气体分析的带有硅悬臂梁的单光纤光声（PA）传感器。该微型气体传感器主要由一个微悬臂梁和一个用于实时检测乙炔气体的非谐振光声池组成。气体通过硅悬臂梁间隙扩散到光声池中。传感器中光声池的体积约为14μL。通过使用1×2光纤耦合器，将1532.8nm分布反馈（DFB）激光器和白光干涉解调模块连接到单光纤光声传感器。利用硅悬臂梁在检测光声信号时提高性能。为消除激光反射光的干扰，采用部分法布里 - 珀罗（F - P）干涉光谱进行相位解调，以实现对乙炔气体的高灵敏度检测。在100s平均时间下实现的最低检测限（MDL）为0.2ppm。此外，计算得到的归一化噪声等效吸收（NNEA）系数为4.4×10 W·cm·Hz。所设计的单光纤光声传感器在变压器故障预警方面具有很大的应用前景。
