OPGW cable fault type and maintenance detection

1, OPGW cable particularity

The optical fiber of OPGW cable is placed in the ground wire of the overhead high-voltage transmission line, which is used to form the optical fiber communication network of the transmission line, and provides communication channels for the power network, such as protection, dispatching telephone, administrative liaison, office automation, dispatching automation, etc. OPGW optical cable is located at the top of the power line, due to the particularity of the position, affected by line power failure, safety and other factors, it is not convenient to carry out OPGW optical cable inspection, maintenance, overhaul.

Therefore, how to do a good job of OPGW optical cable maintenance, inspection, detection, in advance to do a good job of OPGW optical cable fault prevention, timely discovery of OPGW optical cable fault, improve the safe and reliable operation of the communication network, for the safe, reliable and stable operation of the power grid, to provide more powerful communication support, is of great significance.

2, OPGW cable fault type

Causes of OPGW cable failure, mainly ice, lightning, tower, wind dance, discharge, shooting, blasting, theft and other hazards.

3, OPGW cable maintenance detection means

OPGW optical cable maintenance detection means, including the following aspects (1), in the OPGW optical cable maintenance, the traditional maintenance is the line personnel in accordance with the specified time for human line patrol, special circumstances do special inspection; (2) In terms of communication, spare fiber core inspection test and substation outdoor inspection are carried out in accordance with the specified time; (3) The temperature measurement of OPGW cable is generally carried out in the substation area. It is more positive to test the temperature for the ground point, and it can find out whether the ground point is well grounded in time. (4) In recent years, some communication departments have installed optical cable online monitoring (OTDR real-time detection), real-time detection of optical cables; ⑤, line department to carry out drone line patrol; In recent years, based on the fully distributed optical fiber sensor technology of Brillouin scattering, the entire process of distributed monitoring and maintenance of OPGW optical cable is carried out.

4, OPGW cable maintenance means of extreme limited

By ice, lightning, tower, wind dance, discharge, shooting, blasting, theft caused by OPGW cable fault, some natural disasters, some man-made disasters, OPGW cable maintenance detection, can not cover everything, every kind of maintenance will be limited.

As we all know, due to the high voltage lines across the mountains, the traditional personnel patrol line has geographical limitations, some can not reach, eyes or glasses will miss patrol. The same goes for drone patrols, which fail to spot problems accurately. Only in the OPGW cable failure, resulting in increased communication attenuation or interruption, communication personnel use OTDR test, get the location of the fault, and then do special inspection, inspection focus, to accurately find the fault point.

OPGW cable injury caused by ice, lightning strike, wind dance, discharge, shooting, blasting and so on, OPGW line will have great stress changes. By detecting the stress distribution in the whole process of optical fiber and cable, the fault point can be found to prevent internal fracture due to excessive stress, resulting in communication interruption and avoid huge losses.

However, it is impossible to predict whether the OPGW cable will be injured by ice, lightning, wind, electric discharge, shooting, or blasting. Only when the communication channel attenuation increases or the fiber core is broken, can we know whether the OPGW cable is injured.

The whole process of optical fiber and cable stress distribution detection, high cost, expensive instrument, OPGW fiber core number, not all, at any time to test, although you can detect a certain interval of time, and compared with the original database data analysis and judgment, draw a conclusion, but can not find the problem in time.

5, timely discovery of OPGW cable fault method

The whole process stress distribution detection is based on the object (OPGW cable) under load test data. The stress distribution is not only related to the material properties and the geometry of the object, but also to the load size and loading mode.

Therefore, when natural disasters such as ice covering, lightning strike and wind dance occur in the area, special inspection Tours should be arranged in time to detect the stress distribution in the whole process. Otherwise, the test data will become fuzzy (cannot be compared) with the passage of time, and it is impossible to judge the mildly injured OPGW cable.

Similarly, when shooting, blasting and other man-made incidents occur in the area, it is also necessary to timely grasp the situation of the incident, timely arrange special inspection, and timely arrange the detection of stress distribution in the whole process. When OPGW cable is faulty, resulting in increased communication attenuation or interruption, then the whole process stress distribution detection is meaningless. Only 24 hours of real-time whole process stress distribution detection, can be found at any time, timely OPGW cable fault!