【作者】 汤敬；

【导师】 李志全；

【作者基本信息】 燕山大学 ， 测试计量技术及仪器， 2004， 硕士

【摘要】 随着光纤光栅紫外刻写技术的迅速发展,使光纤光栅具有了可重复和可连续在一根光纤上制作多个光纤光栅的现实性,为光纤传感拓宽了发展空间;同时给应变和温度的分布式测量创造了新的模式,即分布式光纤光栅测量模式。本文以分布式光纤光栅应变和温度传感网络的系统设计和实验研究为目的,归纳了目前光纤光栅传感器的发展趋势以及在实际应用中需要解决的几个主要问题,并从光纤光栅传感头设计、传感机理、光纤光栅温度和应变传感网络的寻址和解调、系统中光源的选取和信号处理模块这四方面展开研究。 首先,论文依次对光纤光栅应变、温度、交叉敏感和同时测量的传感原理进行了详细阐述;并且分析比较了常用的几种复用寻址技术和信号解调技术,提出采用频率调制连续波的复用技术和波分复用技术相结合来解决光纤光栅传感网络的复用寻址问题,采用光纤双折射 Sagnac 环型边缘滤波器的边缘滤波技术对传感信号进行解调,通过理论分析和实验研究证实了系统方案的可行性。 其次,设计了分布式光纤光栅温度、应变测量系统。对整个系统的各组成模块和具体器件进行了原理分析和设计。基于光纤光栅的温度和应变响应特性,提出采用预应变的传感头设计方案同时测量温度和应变,并自行设计了光纤双折射 Sagnac 环型边缘滤波器的解调系统。 最后,进行了光纤布拉格光栅的温度和应变特性测试实验,对利用预应变设计的温度和应变同时测量的传感头存在的误差进行了详细的理论分析;进一步对光栅阵列的寻址过程和信号解调进行了仿真实验研究,并阐述了影响系统测量精度的各种因素以及解决办法。更多还原

【Abstract】 Due to the development of fiber grating’s UV writing technology, FBG possesses the reality that it can be repeatedly and continuously writing several FBG in one fiber, and makes more space for grating sensor. At the same time it creates a new model for the distributed measurement of temperature and stain, namely distributed FBG measurement model. The purpose of this paper is to discuss the system design and experiment research of strain and temperature sensing network of the distributed FBG. The development trend of FBG sensing and several questions to be solved in the practical application are summarized. We study from the following four aspects: the design of sensing head of FBG; the sensing principle; the addressing and demodulation of strain and temperature sensing network of the distributed FBG; the choice of light source and signal demodulation. First, the paper gives more details on the sensing principle of FBG temperature, strain, cross-sensitivity and simultaneous measurement. Further- more, it analyses several kind of multiplexing addressing and signal demodulation technology and proposes a method, which integrates frequency demodulation continuous wave with wavelength division multiplexing, to solve the multiplexing addressing problem of FBG sensing network. The technology of brim filter waves of double refraction fiber Sagnac brim filter is adopted to demodulate sensing signal. The proposed system scheme is testified to be feasible by theoretical analysis and experimental research. Second, temperature and strain measurement system of distributed FBG is designed. The constituent modules and material parts of the whole system are analyzed on principle and designed. Due to temperature and strain performance of FBG, the design scheme of pre-strain sensing head is adopted for simultaneous measurement temperature and strain. The center wavelength is scanned and identified by F-P filter. Finally, temperature and strain performance of FBG is tested and the error of sensing head for simultaneous measurement temperature and strain is given detailed analysis and experimental simulation. Furthermore, addressing progress and signal demodulation of grating array are studied by simulation experiments, and various factors that influence measurement accuracy and their solutions are expatiated.更多还原