物理学报2025，Vol.74Issue(7)：112-120,9.DOI:10.7498/aps.74.20241652
基于动态标定的拉曼分布式光纤测温系统研究
Research on Raman distributed fiber temperature measurement system based on dynamic calibration
摘要
Abstract
Distributed optical fiber temperature measurement system is widely used in the fields of substation,power cable,natural gas transmission pipeline and other temperature measurement systems.It can continuously measure the temperature information at each location along the sensing direction.Raman distributed optical fiber temperature measurement system demodulates the temperature information based on Raman Stokes scattered light and anti-Stokes scattered light power,and the Raman scattering light power directly affects the temperature measurement accuracy.So,it is a challenging task to control the hardware of the system to ensure the feasiblity of the Raman sacttering signals.The laser pulse power,and the gain of avalanche photodetector may vary randomly in the system,resulting in fluctuations in the acquired Raman scattered light power data.Therefore,a scheme of Raman distributed fiber temperature measurement system based on dynamic calibration is proposed in this work,and by setting up the temperature calibration unit and combining the proposed power correction algorithm and previous calibration data,the Raman Stokes scattering light and Raman anti-Stokes scattering light power are calibrated at the same laser pulse power level and avalanche photodetector gain,thereby improving the temperature measurement accuracy of the system.For the performance demonstration of the new scheme,the experimental system adopts 50-ns laser pulse to carry out temperature measurement experiments with a 4.6-km long single-mode fiber.The results show that in the temperature measurement range from 35 ℃ to 95 ℃,based on the traditional temperature demodulation algorithm,the temperature deviation measured is in the range from-5.8 ℃ to 1.0 ℃,and the root mean square error is 4.0℃,and by the dynamic calibration algorithm,the deviation of deviation measured is within-0.8 ℃ to 0.9 ℃ and the root mean square error is 0.5 ℃.Therefore,the novel Raman-type distributed optical fiber temperature measurement system proposed in this work has the function to dynamically correct the Raman-type scattered light power to suppress the influence caused by instability of the key devices such as pulsed laser and avalanche photodetector and improve the temperature measurement accuracy,which is valuable in practical engineering applications.关键词
分布式光纤传感/拉曼散射光/动态标定/功率校正Key words
distributed optical fiber sensing/Raman scattered light/dynamic calibration/power correction引用本文复制引用
冯玉祥,汪雨辰,童家欢,吕立冬..基于动态标定的拉曼分布式光纤测温系统研究[J].物理学报,2025,74(7):112-120,9.基金项目
国家自然科学基金(批准号:51977001)资助的课题. Project supported by the National Natural Science Foundation of China(Grant No.51977001). （批准号:51977001）
