反射型保偏光纤温度传感器

Reflection polarization maintaining optical fiber temperature sensor

基于保偏光纤中偏振模式干涉理论，提出了一种反射型保偏光纤温度传感技术并推导出传感方程，理论分析表明这种温度传感器精度高，可通过改变保偏光纤传感头长度的方法方便地调整测量范围．针对大型电力变压器绕组线圈的温度监测需要，利用特制的耐高温保偏光纤，在传感头和封装形式上进行了特殊设计，研制出实用的光纤温度传感器，其传感头满足了热油和高电压绝缘的要求．利用这种传感器进行了实际测试研究，基于模型线性化技术，在常温～180℃的温度范围内实现了线性输出．在冰水混合形成的绝对0℃环境下的稳定性测试表明其测量精度和稳定性均优于0．15℃．

A reflection polarization maintain optical fiber temperature sensor was proposed based on the polarization mode interference theory in polarization maintain optical fiber and the sensing equation was derived. Analyses prove this sensor can achieves high accuracy and the measurement range can be adjusted easily by changing the polarization maintaining optical fiber sense probe length. For the demand of field temperature monitoring of huge power transformers, a prototype with special high temperature polarization maintain optical fiber sensing probe and sealed package was made and the sensor probe can stand the harsh environment of hot oil and＇high voltage. With this prototype, the temperature within range 0℃- 180℃ was measured and the linear output was obtained after model linearized and date processed. Long time measurement was investigated in 0℃ environment formed with mixer of ice and water, the result shows the sensor stability and accuracy were both better than 0.15℃.