布里渊-拉曼融合型分布式煤矿安全监测关键技术研究

Spontaneous combustion and collapse are two main factors contributed to major coal mine production accidents. However, coal mine safety monitoring can provide effective guarantee for it. At present, our country widely used electric sensor method to monitor temperature in gob area of coal and pressure & strain of curtain wall, whereby it has some problems such as single monitor parameter, small monitor range, high cost, incapable of realizing real distribution measurement. This project study on .decoupling principle between temperature and strain double parameters in Brillouin scattering frequency shift signal firstly. The Decoupling model of temperature and strain is established by fused Brillouin-Raman sensor technology. To realize synchronous acquisition of two parameters signal, double light source time-sharing multiplexing technology is used. Parallel microwave sweep frequency method is proposed. Mosaic method of segmented spectrum signal is studied for realizing fast demodulation on Brillouin scattering frequency shift signal. Experimental loading method of temperature and strain parameters is designed. Through experimental testify on Fused Brillouin-Raman sensor technology, experimental method and signal processing algorithm are optimized, moreover the results of decoupling principle and Parallel microwave sweep frequency method are evaluated. The terminal purpose could provide theoretical foundation and technology support to realize synchronous monitoring between temperature and strain. It also provide a novel way to develop multi-parameter simultaneous measurement technology in coal mine safety monitoring.

自燃与坍塌是引起煤矿重大安全生产事故的最主要因素。而煤矿安全监测则可为安全生产提供有效保障。我国目前普遍采用电传感方式监测煤矿采空区温度与支护墙压力/应变，存在着监测参量单一、监测范围小、不能实现真正分布式测量的问题。本项目拟从布里渊散射频移信号中温度/应变双参量的去耦原理入手，通过布里渊-拉曼融合传感技术，建立温度/应变信号去耦模型，采用双光源分时复用技术，实现双参量信号同步采集；提出并行微波扫频方法，并对分段频谱信号的拼接方法进行研究，实现布里渊散射频移信号快速解调；设计温度/应变双参量加载实验方法，对布里渊-拉曼融合传感技术进行实验验证，优化实验方法及信号处理算法，评价温度/应变信号去耦方法和并行微波扫频方法的效果。最终为布里渊-拉曼融合型温度/应变双参量同时监测技术的实现提供理论基础和技术支持，也为煤矿安全监测中多参量同时测量技术的发展提供一种新的路径。

目前我国煤矿采空区温度与支护墙压力/应变监测存在监测参量单一，范围小，无法实现分布式测量的问题。布里渊-拉曼融合传感技术的提出为解决这一问题提供了理论基础。本项目深入探索研究了布里渊-拉曼融合型分布式煤矿安全监测关键技术。. 本项目完成了基于DFB半导体激光器连续光源系统的研制，实现了对布里渊分布式传感系统激光器电流和温度的精准控制，满足布里渊分布式光纤传感系统需要的激光光源，设计了一种高消光比光电调制器的脉冲光源调制系统，实现了将EOM输出脉冲光的消光比稳定在50dB以上。. 本项目完成了掺铒光纤放大器的研制，提出了多通道并行微波扫频方法，搭建了布里渊分布式光纤传感检测系统，进行了小波算法对布里渊散射信号去噪的研究，验证了该系统的可靠性，为布里渊-拉曼融合分布式煤矿安全检测提供了理论依据。. 本项目完成了拉曼传感子系统中APD的研制和实验验证，搭建了拉曼传感实验系统，该系统的温度测量误差小于0.7℃，50℃到100℃的响应时间小于17s，，提出了拉曼传感系统温度信号峰值位移解调方法，改善了传统分布式光纤拉曼温度测量系统的性能。. 本项目完成了布里渊-拉曼融合的传感实验系统的搭建，对该融合传感实验系统设计了温度、应变加载的综合实验，验证了温度/应变去耦算法的可行性。实验结果表明：融合传感系统的温度测量误差小于1.1℃，应变测量误差小于24uε。. 本项目完成了布里渊光纤传感系统应变校准装置的设计。该装置可对光纤施加标准应变，结合布里渊光纤传感系统获取光纤中布里渊散射光信号的频移量，实现对应变-频移系数的标定和校准。