基于参考光栅的光纤光栅应变测量温度补偿

Temperature Compensation of FBG Strain Measurement Based on Reference FBG

光纤光栅传感器能够进行温度、应变或其他诸多参量的测量,已经在一些大型建筑结构中广泛应用。实际测量时,温度和应变是同时存在的,无法分辨出应变和温度各自引起的波长变化,必须采取措施进行补偿或区分。设计了一种光纤光栅应变测量系统的温度补偿方案,该方案使用一个与测量光栅的温度特性相同的光纤光栅作为参考光栅,参考光栅只感受温度的变化,不受应变的影响。实验结果表明,补偿后基本消除由于温度变化引起的测量误差,测量结果的线性拟合度达0.998。

Fiber Bragg gratings（ FBG） have been widely used in large architecture which can measure temperature,strain,and so on. In practical measurement process,temperature and strain cannot be distinguished because they exist simultaneously,so compensation measure must be employed. A fiber Bragg grating strain measurement scheme with temperature compensation is designed. It uses a reference FBG with the similar temperature characteristic of sensing FBG. The reference FBG is influenced only by temperature,not by strain. The measurement result shows that the errors caused by the changes of the temperature are basically eliminated,and the degree of linear fitting can be up to 0. 998.