A Passive Optical Fiber Anemometer for Wind Speed Measurement on High-Voltage Overhead Transmission Lines

Measurement of wind speed is an essential part of overhead transmission line monitoring. To overcome the drawbacks of the existing anemometer, such as the requirement on field power, the sensitivity to electromagnetic interference, and the unavailability of real-time measurement, a novel anemometer is developed on the basis of the fiber Bragg grating (FBG) sensing technique. In the anemometer, a beam with uniform strength was used to measure the force generated by the wind; two naked FBGs were symmetrically glued on the upper and lower surfaces of the beam to solve the problem of cross-sensitivity between strain and temperature of FBG sensing. Furthermore, the temperature effect on the zero output was investigated by putting the FBG anemometer into a temperature-controlled cabinet, and the experimental results indicated that the temperature effect on the zero output of the wind speed was less than ±5 pm (-10° C to 50 °C). The results from the wind tunnel experiment indicated that the measurement error of the anemometer was less than ±0.5 m/s.