改进型光纤布拉格光栅温度检测系统研究

传统的光纤布拉格光栅温度检测系统适用于大范围、多点位的实时温度检测领域,但其温度响应稳定性差,布拉格光栅中心波长偏移量随温度变化量的线性度差。为提高系统温度检测稳定性及其检测精度,设计了一种改进型光纤布拉格光栅温度检测系统。该系统采用双光纤并行采集同点位温度并进行差分处理的方法,实现对测温过程中随机误差的实时有效消除,进而达到提高测温稳定性及检测精度的目的。计算推导了该模式下光纤布拉格光栅中心波长偏移量关于温度变化量的函数关系,给出了新式光纤光栅探头的结构。实验将改进型光纤布拉格光栅温度检测系统与传统系统进行对比,结果显示,改进型系统的温度测量精度可达0.5℃,相比传统系统得到了提升,同时,其测温误差也明显优于传统系统,说明采用该设计可以提高系统测温的稳定性。

Research on Temperature Detection System Based on Improved Fiber Bragg Grating

Traditional temperature detection system based on Fiber Bragg Grating is suitable for large‐scale ,real‐time multi‐point temperature detection field .But its stability of temperature response is poor ,shift amount of Bragg grating center wavelength is poor linearity with temperature variation .In order to improve the stability for system and temperature detection accuracy of the system ,an improved temperature detection system based on Fiber Bragg Grating was designed .The method of dual fiber parallel acquisition for temperature data was used on the same point ,and then center wavelength data was differentially processed .It was realized that the random errors of the system were effectively real‐time eliminated in the process temperature .The function rela‐tionships of center wavelength shift amount of Fiber Bragg Grating and temperature variation was derived in this mode ,and the new structure of the probes for Fiber Bragg Grating was designed .In the experiments ,measurement data of Improved tempera‐ture detection system based on Fiber Bragg Grating was compared with the data of traditional system .Experimental results show that temperature measurement accuracy of improved system was up to 0.5 ℃ ,and its accuracy has been improved compared to conventional systems .Meanwhile ,the measurement error was significantly better than traditional systems .It proved that the design can improve the stability of temperature detection for the system .