Practice of optical fiber sensing technologies in power transmission lines and towers

Optical fiber sensing technologies have been developed for more than forty years and applied in many different areas. They are suitable for power systems because of their electromagnetic immunity, their safety in nuclear environments, distributed sensing capability, their small size and so on. The practices of optical fiber sensors in power systems is growing explosively. We report the recent two-year results on the health monitoring of power transmission lines and towers based on optical fiber sensing technologies in Henan, including phase sensitive optical time domain reflectometry (phase-OTDR) based transmission line galloping measurement, Raman scattering based optical time domain reflectometry (R-OTDR) based transmission line distributed temperature sensing, and Fiber Bragg Grating (FBG) based tower strain measurement. The optical fibers in optical fiber composite overhead ground wire (OPGW)/optical phase conductor (OPPC) are used as sensing fibers to monitor the galloping and the distributed temperature along the transmission lines successfully, which may be the most convenient and low-cost way to use fiber sensing technologies. More than one hundred well packaged FBGs had been installed on a strain tower and realized the dynamic strain measurement, especially under the strong dynamic strain introduced by the transmission line galloping. The results of all those optical fiber sensors are relative and some considerations of optical fiber sensing net in power system would be discussed as well.