Development of FBG Tension and Tilt Sensors Applied to Ice Monitoring of Overhead Transmission Lines

Abstract

Overhead icing transmission lines face great danger of stable operation. Based on the existing transmission line monitoring power, susceptible to electromagnetic interference and other shortcomings and Fiber Bragg Grating (FBG) sensor have the advantages of anti-electromagnetic interference, high sensitivity, small volume and so on, we develop a set of FBG sensing technology of transmission line icing monitoring system. In order to improve the existing FBG column type weighing sensor performance, better monitoring of wire icing conditions developed for resistance to a tower of the FBG double closed-loop U type tension sensor, can be a number of important parameters of the measurement of conductor icing thickness, tension, and sag. The FBG dual closed-loop U type tension sensor is composed of two parts, the FBG sensor and the elastic body. In the sensor, through the design of double closed loop U-shaped structure formed a high precision and anti-partial load ability of the force sensing element; elastic force, in the U-shaped groove surface can be accordingly generates the tensile and compressive principal strain, two FBG wavelength value subtraction that can eliminate the cross sensitivity of FBG strain and temperature and without additional compensation measures. Laboratory test results show that the developed fiber Bragg grating sensor force measuring unit high linearity, pull sensing sensitivity for 0.0413pm/N, resolution of 24.21N, nonlinear error was 1.7%, accuracy is 2.37%, relative previous FBG column type weighing sensor, nonlinear error decreased by 40%, the accuracy is improved by 1.2 times. All aspects of performance have improved.