Differences and advantages of OPGW cable and ADSS cable

OPGW and ADSS optical cables are basically similar in structure and type, and both are composed of optical fiber units responsible for signal transmission and reinforcement units responsible for mechanical strength. The difference is that the OPGW optical cable strengthening unit is made of metal wire, and the ADSS optical cable strengthening unit is aramid yarn. From the perspective of optical performance, OPGW and ADSS optical units are the same, and both can meet the communication requirements in terms of optical fiber transmission.

Fiber dispersion, signal attenuation, transmission distance, etc. can meet the design requirements. ②From the point of view of the mechanical strength of the optical cable, the ADSS optical cable has better ice-covered overload capacity, and the OPGW sag characteristic is better. The maximum sag of OPGW optical cable is 1.64 to 6.54 m smaller than that of ADSS optical cable within the span of 200 to 400 m under the condition of 10 mm icing. At the same time, the vertical load, horizontal load and maximum operating tension of OPGW optical cable are larger than that of AOSS optical cable. Therefore, OPGW optical cables are generally more suitable for mountainous areas with large spans and height differences.

1.3 OPGW and ADSS optical cable construction scheme OPGW optical cable is built on the ground wire bracket of the collector line tower, and the optical fiber is placed in the overhead ground wire to act as a composite optical fiber overhead ground wire that combines lightning protection and communication functions. The following factors need to be considered when constructing OPGW cables:

①The safety factor of the OPGW composite optical fiber ground wire should not be less than 2.5, and should be greater than the design safety factor of the conductor, and the average operating stress should not exceed 25% of the failure stress.

②The distance between the wire and the ground wire of the OPGW composite optical fiber should meet the lightning protection requirements.

③ During the normal operation of the line and in the event of an accident, the OPGW composite optical fiber ground wire should meet the thermal stability requirements. ADSS optical cable is built on the main material of the tower body of the collector line. It is an all-dielectric self-supporting optical cable. It needs to erect a common ground wire at the same time to undertake the lightning protection requirements of the collector line.

The following factors should be considered in the construction of ADSS optical cable: 

① The safety factor of ADSS optical cable should not be less than 2.5, and should be greater than the design safety factor of the conductor, and the average operating stress should generally take 18% to 20% of the failure stress.

② The ADSS optical cable should meet the strength and foundation stability check calculation of the erected tower.

③ The ADSS optical cable should be protected against electrical corrosion, animal bites, abrasion between the tower and the iron tower and whiplash with the wire when the wind deflects.

④ Under the action of external force such as strong wind or icing, ADSS optical cable crossover and ground distance have sufficient margin.

From the above it can be seen that:

①From the perspective of construction and operation and maintenance, OPGW optical cable has all the functions and performance of overhead ground wire and optical cable, integrating mechanical, electrical and transmission advantages, one-time construction, one-time completion, high safety and reliability, and strong anti-risk ability; ADSs The optical cable needs to erect a common ground wire at the same time. The installation positions of the two are different, and the construction is completed in two times. The normal operation of the power line will not be affected in the event of an accident, and the maintenance can also be performed without power failure.

②From the perspective of project cost indicators, OPGW optical cable has high requirements for lightning protection, and the cost of the single unit is higher; ADSS optical cable does not have lightning protection, and the single unit cost is lower. However, the ADSS optical cable also needs to install a common ground wire for lightning protection, which needs to increase the construction cost and material cost. Therefore, in terms of overall cost, OPGW optical cable saves investment in wind farms than ADSS optical cable.