New technology helps State Grid Corporation carry out OPGW optical cable operation and maintenance

Recently, the State Grid Communication Company, in conjunction with the State Grid Sichuan Electric Power, innovatively applied the BOTDR (distributed Brillouin sensing) technology to the elimination of hidden dangers in the OPGW optical cable of Sichuan Yuecheng Substation Muxi Substation. The length of fault location was reduced by one hour from dozens of hours of traditional methods, and the accuracy of fault location was reduced by meters from kilometers.

Accurate positioning of OPGW breakpoints and monitoring and troubleshooting of optical fiber performance degradation have been the difficulties and pain points in the operation and maintenance of electric power communication network. During the operation of the communication system, the State Grid Communication Dispatching and Monitoring found that the performance of the communication optical path of the State Grid backbone communication system Sichuan Yuecheng Substation Muxi Substation was in a critical state, and the optical path was frequently interrupted. The organization and inspection found that the attenuation and performance degradation of multiple OPGW optical fiber cores in this section occurred at the same location, and there was a risk of cable strand breakage. In order to eliminate hidden dangers, the State Grid Communication Company, in cooperation with the State Grid Sichuan Electric Power, sent personnel to the site using the transmission line maintenance time window to organize and complete the OPGW cable fault troubleshooting and hidden danger elimination.

In this work, the State Grid Communication Company adopted the new technology of BOTDR (distributed Brillouin sensing) to replace the traditional fault detection method of "OTDR fault location+manual line patrol", and realized the automatic calibration of the OPGW optical cable connection tower points by using the optical fiber Brillouin reflection frequency shift characteristics, successfully completed the rapid and accurate positioning of the 10 fault cores of the OPGW optical cable at three fault points, and the fault location time was reduced by one hour from the tens of hours of the traditional method, The fault location accuracy is reduced from kilometer level to meter level. Due to the adoption of BOTDR technology, this optical cable fault elimination does not require manual line patrol observation, open-box observation and other traditional processes, which effectively solves the practical problems of difficult and time-consuming fault location in optical cable operation and maintenance. At the same time, the technology was used to identify two potential safety hazards, namely the depletion of fiber core surplus length, which could not be found by traditional means, namely the deterioration of performance, and provide strong support for the operation and maintenance of optical cables.

BOTDR technology is used to measure and locate the axial stress and temperature of the optical fiber by detecting the frequency shift of the back Brillouin scattering light in the optical fiber. It has been widely used in the stress detection of bridges, pipelines and other scenes. By deepening the research and application of BOTDR technology, State Grid Communications Corporation has achieved the triple effect of accurate positioning of hidden danger points, substantial reduction of defect elimination time, and active detection of hidden dangers of optical cables, opening up a new path for the operation and maintenance of special optical cables for power communications.