基于光路自动准直的甲烷遥测技术  

Methane Telemetry Based on Optical Path Automatic Collimation

作　　者：季文海[1] 宋迪 焦月 马龙岩 李国林[1] Ji Wenhai;Song Di;Jiao Yue;Ma Longyan;Li Guolin(College of Control Science and Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,China)

机构地区：[1]中国石油大学(华东)控制科学与工程学院,山东青岛266580

出　　处：《光学学报》2020年第18期119-127,共9页Acta Optica Sinica

基　　金：山东省重点研发计划(2019GGX104103,2019GHY112084)。

摘　　要：针对目前甲烷遥测装置因光学准直固定,在不同检测环境使用时不能进行动态调整的问题,在光路准直设计中引入了电控可变焦透镜,实现了光路自动准直。测试结果表明,针对不同的检测距离和辅助目标,通过改变电控可变焦透镜的驱动电流可实现快速变焦,在动态调节激光光束发散效果的同时可使遥测装置的接收光功率最大化,其接收光功率相比无变焦透镜接收光功率可提高1.7倍以上,同时可提高检测系统的信噪比。针对变焦透镜在遥测应用中出现的新问题,如重力效应引起的光束偏转效应,提出了形变模型,并进行了理论计算和仿真分析。使用甲烷气袋进行泄漏模拟测试,通过Allan方差分析得到:当积分时间为18 s时,极限标准差达到1.51×10^-6。对装置进行实地测量,测试距离为52.2 m,检测到楼道空气中存在4.95×10^-6浓度(体积分数)的甲烷气体。该研究展示了使用电控可变焦透镜实现光路自动准直和优化在气体泄漏遥测装置中的可行性与应用价值。To solve the problem that a methane telemetry device can not be dynamically adjusted when it is used in different detection environments due to its fixed optical collimation,an electronically controlled zoom lens is introduced into the optical path collimation design to achieve automatic optical path collimation.Test results show that for different detection distances and auxiliary targets,the fast zoom can be achieved by changing the driving current of the electronically controlled zoom lens.The receiving optical power of the telemetry device can be maximized while dynamically adjusting the laser beam divergence effect.Compared with the non-zoom lens,the receiving optical power can be increased by more than 1.7 times,and the signal-to-noise ratio of the detection system is improved.In view of the new problems of the zoom lens in telemetry applications,such as beam deflection caused by the gravity effect,a deformation model is proposed,and theoretical calculation and simulation analysis are carried out.A methane gas bag is used to conduct a leak simulation test.Through the Allan variance analysis,we obtain that when the integration time is 18 s,the limit standard deviation is 1.51×10^-6.The field measurement for the device is conducted,the test distance is 52.2 m,and the methane gas with the concentration(volume fraction)of 4.95×10^-6 is detected in the corridor air.The research demonstrates the feasibility and the application value of using an electronically controlled variable focus lens to realize automatic collimation and optimization of the optical path in a gas leakage telemetry device.

关 键 词：测量 甲烷遥测 自动光学准直 电控可变焦透镜 光束重力偏转效应 

分 类 号：TN21[电子电信—物理电子学]