【作者】 吴晓冬；

【导师】 陈军；

【作者基本信息】 浙江大学 ， 光学工程， 2005， 博士

【摘要】 近年来,光纤光栅及其在光纤传感器和光纤通信领域中的应用研究引起了人们普遍的关注。光纤光栅是一种性能优良的敏感元件,可以对温度、压力和应变等进行传感。尤其是在一根光纤中可连续写入多个光栅构成光栅阵列,因此,将光纤光栅阵列与波分和时分复用技术相结合,实现网络传感。这种传感器在大型结构（如水坝、桥梁、重要建筑和飞行器、舰艇等）和特殊场合（如矿井、油田等）的安全监测方面具有极为广泛的应用前景。 本人作为浙江大学与德国波茨坦地学研究中心（GeoForschungsZenturm Potsdam）联合培养的博士研究生,由德国联邦教育与科技部（BMBF）（项目编号 CHN/167）和德国波茨坦地学研究中心资助,在德国进行了为期一年半的研究工作。在此期间参与了欧盟的Corinth Rift Laboratory中的3F（Faults,Fractures & Fluids）-Corinth研究项目和德国的Potsdam Kaiser Bahnhof建筑现场应变监测项目,这些项目的特点是光纤Bragg光栅传感器的应用的工程化。 本文主要以光纤Bragg光栅（FBG）为研究对象对光纤Bragg光栅静态应变传感网络、光纤Bragg光栅动态应变传感、光纤Bragg光栅传感技术与其他传感技术比较以及光纤Bragg光栅应变传感特性等方面进行了研究。主要内容包括: 介绍分析光纤光栅特性的基本理论,用耦合模理论分析了均匀周期光纤Bragg光栅的光谱特性,并从理论上分析了光纤Bragg光栅对温度和应变的传感原理,讨论了光纤Bragg光栅应变传感技术。 提出并建立了一套完整的分布式光纤Bragg光栅静态应变传感网络系统。该系统着重研究解决了光纤Bragg光栅静态应变传感网络技术的现场实际应用问题。系统解决了波分复用和时复复用的结合技术,实现光纤Bragg光栅深度传感网络。系统解决了光纤Bragg光栅静态应变传感现场应用传感数据精度和可靠性问题,在获得高精度传感信号同时能够识别错误信号;提出了光纤Bragg光栅静态应变传感器在恶劣应用环境中的备份方案;应用计算机软件对系统进行测量控制与管理,实现了智能化集中控制系统;实现了远程控制管理。 提出并建立了一套基于温度控制滤波光纤Bragg光栅的光纤Bragg光栅动态应变传感系统。解决了因传感环境温度变化带来的传感光纤Bragg光栅的Bragg波长漂移和窄带滤波器滤波波长的匹配问题。系统采用计算机完全控制,实现了智能化动态光纤Bragg光栅动态应变传感。本系统的信噪比达到15dB,动态应变传感精度达到了9.745×10^-10/(Hz^1/2),绝对应变测量值达到了160nε。 对光纤Bragg光栅应变传感器在悬臂梁结构上的应变传感进行了研究。将更多还原

【Abstract】 In recent years, there is wide attention on fiber grating and its application in fiber sensors and fiber communications. As an excellent sensor, Fiber Bragg ggrating (FBG) sensor offer many important advantages, and can measure lots of properties, such as termperature, pressure, strain and so on. It is suitable to form FBG array, by means of writing them into a fiber continuously. With Time Division Multiplexing (TDM) and Wavelength Division Multiplexing (WDM) Technology, the FBG sensor array can build FBG sensor network, which has wide prospect for detecting the properties of the huge buildings and dangerous situations, such as the dam, bridge, mine, oil field etc.As a Ph.D candidate studing in Zhejiang University and GFZ-Pptsdam (GeoForschungsZenturm Potsdam), supported by Germany BMBF (Project No: CHN/167) and GFZ-Potsdam, I had studied in germany for one and half year. In the period, I had taken part in the Europen Union Corinth Rift Laboratory 3F (Faults, Fractures & Fluids) -Corinth Porject and Germany Potsdam Kaiser Bahnhof building strain detecting project.In the dissertation, the FBG sensor is studied, including FBG static strain sensor network, FBG dynamic strain measurement, Compareing between FBG strain sensor and traditional strain sensor, FBG strain sensor character etc. The main contents are taken as follows:The fundamental theory of the fiber grating is introduced. The spectrum of FBG is analyzed by the coupling-mode theory, and FBG sensor theory for strain and temperature is analyzed. The FBG strain senor technology which applied in the dissertation is discussed.A distributed FBG static strain sensor network is designed and established. The system is focus on the solution of FBG sensor field application. With TDM and WDM technology, system can measure a long distance strain in very deeply underground well. The system can drop the wrong signal beside a high resolution. With a backup FBGs, the system can adapt the badly condition, which will damage the FBG. With a center computer communication with all devices, the system became a smart system, which can measure the strain automatically and can be remote controlled.A FBG dynamic strain sensor system based on temperature controlledfilter FBG is designed and established, which sloved the filter FBG and sensor FBG wavelength match problem caused by the temperature variation. The system is totally computer controlled and smart work. The singal noise ratio (S/N) of system reach 15dB, dynamic resolution is 9.745x10-10/(Hz1/2), and the absolute resolution is 160nThe FBG strain sensor applied in cantilever is studied in experiments and theories. The FBG sensor signal is compared with the result of acceleration sensor, modal analysis and finite element analysis.FBG strain sensor character is studied in experiments and theories. The memory effect of FBGand linear relationship between FBG Bragg wavelength and strain are analyzed.更多还原