横担是电力系统塔架结构中承力较多的构件, 在线路覆冰、舞动等因素影响下横担主材受力过大, 容易造成损坏。在研制的电力系统塔架模型鸭嘴式横担主材的上下表面, 采用环氧树脂做为粘贴剂分别安装四根光纤Bragg光栅, 实时监测横担应变。实验通过调整荷载改变横担主材所受应力, 从而使得光纤Bragg光栅中心波长发生移位。荷载实验表明, 在鸭嘴式横担端部进行加载和卸载时, 位于4个测点的光纤Bragg光栅的实验灵敏度分别为: 6 pm/kg, 2 pm/kg, 3 pm/kg, 2 pm/kg; 线性度分别为2.6%FS, 6.1%FS, 2.7%FS, 4.5%FS。

Cross arm withstands more force in the tower of power system than other components, it’s easy to cause the damage of the cross arm by the excessive weight of line ice, wave, or other physical factors. A model of power transmission tower with a duckbill-type cross arm is developed, four fiber Bragg gratings are mounted on the upper surface and the lower surface of main beam of duckbill-type cross arm with epoxy resin. The strain of main beams are induced by the stress of loading, which causes the wavelength shift of fiber Bragg gratings. When loading and unloading on the ends of duckbill-type cross arm, the experiment indicates that load sensitivities of four measuring gratings are respectively 6 pm/kg, 2 pm/kg, 3 pm/kg, 2 pm/kg, the repeatability errors are 0.7%FS, 4.1%FS, 1.9%FS, 3.0%FS.