基于游标效应的光纤氢气传感理论及关键技术研究

As an ideal cleaning energy, hydrogen has been widely used in the fields of energy, production, and security. At the same time, in order to avoid the explosion hazards of hydrogen and monitor the operation statuses of equipment such as voltage transformer, it becomes more and more important to research and develop a hydrogen sensor for high-sensitive, high-precision, distributed, long-distance, long-term, real time and on-line measuring of hydrogen concentration. Based on these, the project combines the advantages of optical fiber sensor and sensitivity enhancement property of optical Vernier effect, and then proposes an optical fiber sensing method based on Vernier effect. The main research contents include: Building a theoretical model to demonstrate that the “Vernier effect” can enhance the measurement sensitivity of optical fiber hydrogen sensor; Designing an all-fiber and reflective hydrogen sensing head structure, which can generate Vernier effect and resolve the cross-sensitivity problems of disturbances such as temperature and moisture to hydrogen concentration; Exploring the preparation and coating method of palladium based sensitive membrane from micro and macro points of view to obtain steady performance, well identification, and rapid response velocity; Proposing a high-precision demodulation scheme of Vernier spectrum, and then exploring its application in distributed hydrogen sensor; Fabricating the prototype of optical fiber hydrogen sensor, and then measuring and analyzing its properties. This study can promote the better development of optical hydrogen sensing technology, and has distinctly interdisciplinary characteristic and broad prospects of practical application.

氢气作为一种理想的清洁能源，被广泛用于能源、生产和安全防护领域，与此同时，为了防止氢气爆炸带来的危害以及实时监控变压器等的运行情况，研究和发展一种本质安全且可实现氢气浓度高灵敏度、高精度、分布式、远程、长期、实时在线检测的氢气传感器变得日益重要。基于此，本项目将光纤传感器的优势和光学游标增敏特性有机结合，提出一种基于游标效应的光纤氢气传感方法。主要研究内容包括：建立游标效应提高光纤氢气传感器测量灵敏度的理论模型；设计一种可产生游标效应的全光纤反射式氢气传感探头结构，并解决温度、湿度等扰动量对氢气浓度的交叉敏感问题；从微观和宏观角度，研究一种性能稳定、鉴别力好、响应速度快的钯基氢敏膜制备及镀膜方法；提出一种高精度的游标光谱解调方案，并探索其在分布式氢气传感中的应用；研制光纤氢气传感器样机，并对其特性进行测试和分析。项目研究可很好地促进氢气传感技术的发展，具有明显的学科交叉性和广泛的应用价值。

氢气作为一种理想的清洁能源，被广泛用于能源、生产和安全防护领域，与此同时，为了防止氢气爆炸带来的危害以及实时监控变压器等的运行情况，研究和发展一种本质安全且可实现氢气浓度高灵敏度、高精度、分布式、远程、长期、实时在线检测的氢气传感器变得日益重要。本项目以游标效应提高传感器测量灵敏度为核心思想，针对氢气浓度检测的应用需求及目前光纤氢气传感器中存在的关键技术问题，探索适用于氢气浓度检测的新理论、 新工艺、新技术和新方法。通过将光纤传感器的优势和光学游标增敏特性有机结合，提出一种基于游标效应的光纤氢气传感方法。理论建立了游标效应的光纤传感倍增模型，实验探索了性能稳定、鉴别力好、响应速度快的的钯基氢气敏感膜及其与光纤的结合方案；设计并搭建了光纤模间干涉仪、光纤F-P干涉仪、基于游标效应的光纤F-P干涉仪氢气传感器，并针对温度交叉敏感、远距离测量、高精度解调等实际问题/需求，优化传感方案，测试结果表明，氢气的测量灵敏度可提高至-2.998nm/%，而且具有易于制备、造价低廉、易于远距离传输、体积小、灵敏度高等优势。上述技术方法为新型光纤氢气传感器的制备和应用奠定理论和技术基础，具有明显的学科交叉性和广泛的应用价值。