Usually, Power optical cables can be divided into three types: Powerline combo, tower and powerline. Power line composite usually refers to the composite optical fiber unit in the traditional power line, which realizes the traditional power supply or lightning protection function in the process of optical fiber communication, mainly including optical fiber composite overhead ground wire (OPGW optical cable), optical fiber composite overhead phase wire (OPPC optical cable), optical fiber hybrid Optical cable (GD), optical fiber composite low-voltage optical cable (OPLC), etc. The tower is mainly composed of ADSS optical cable and metal self-supporting optical cable (MASS).
OPGW optical cable
Optical Fiber Composite Overhead Ground Wire (also known as optical fiber composite overhead ground wire). The optical fiber is placed on the ground of the overhead high-voltage transmission line to form an optical fiber communication network on the transmission line. This structure has dual functions of grounding cable and communication, and is generally called OPGW optical cable.
Optical fiber composite overhead grounding cable - it has the traditional grounding lightning protection function, provides lightning protection for the transmission line, and transmits information through the optical fiber composite in the grounding cable. There are three types of OPGW structure: aluminum tube type, aluminum frame type and stainless steel tube type.
One of the key technologies of OPGW optical cable is the temperature rise and high operating temperature caused by short-circuit current.
In the first two structures of the OPGW optical cable, the aluminum tube and aluminum frame will generate high temperature under the impact of short-circuit current. And spread to the inside, and then affect the fiber transmission or even fiber breakage, the stainless steel tube has been significantly improved. If the structure contains aluminum, the temperature exceeds 200 ° C, the first is the irreversible plastic deformation of aluminum. When the structure is damaged, the increase in the sag of the OPGW optical cable can not only keep a safe distance from the wire, but also may collide with the wire. If the structure is an all-steel structure, it can work at 300°C for a short time.
Fiber optics can be installed on top of transmission line pylons due to their immunity to electromagnetic interference and light weight, regardless of optimal installation location and electromagnetic corrosion. Therefore, OPGW has the characteristics of high reliability, superior mechanical properties, and low cost. This technique is particularly applicable and economical when laying or replacing existing grounding wires.
Opticalphase Conductor, referred to as OPPC, is a new type of special optical cable for power communication. It is an optical cable that combines optical fiber units into conductors with a traditional phase wire structure. It makes full use of the line resources of the power system itself, especially the distribution network system to avoid conflicts with the outside world in terms of frequency resources, routing coordination, electromagnetic compatibility, etc., so that it has dual functions of power transmission and distribution.
OPPC fiber optic cables have unique optical fibers in the fiber bundle tube structure, so pre-twisted fiber optic cable accessories must be installed to protect the optical fibers. There are three advantages to using pre-twisted joints. First, the structure is simple and fast. There is no need to pull heavy compressors, crimping pliers, etc., which improves labor efficiency and reduces manual labor. In contrast, pre-twisted splices are good conductors. Good electrical conductivity, remarkable energy-saving effect. The third is to install pre-twisted wire accessories on the line, which expands the contact surface of the wires, increases the length of the wires, uniform force, reduces the fatigue of the wires, prolongs the service life of the wires, and improves the shock resistance.
Abbreviation for AllDielectricSelf-Supporting (full dielectric self-supporting). All dielectric, that is, the cable uses all dielectric materials. Self-supporting force refers to the strength of the optical cable itself to bear its own weight and external loads. The name explains the environment and the key technology of the cable: since it is self-supporting, its mechanical strength is important: all dielectric materials are used because the cable is exposed to high voltages and currents and must be able to withstand them.
Impact: Due to the use of overhead poles, it is necessary to install a matching pendant on the pole. That is, ADSS optical cable has three key technologies: mechanical design of optical cable, determination of hanging point, selection and installation of supporting hardware.
Mechanical properties of ADSS optical cable The mechanical properties of optical cable are mainly reflected in the maximum working tension, average working tension and ultimate tensile strength of the optical cable. The national standard for ordinary optical cables clearly stipulates the mechanical strength of optical cables under different usage methods such as overhead, pipeline, and direct burial. ADSS optical cable is a self-supporting overhead cable, so in addition to being able to withstand the long-term impact of its own gravity, it can also withstand the baptism of the natural environment. If the mechanical performance design of the ADSS optical cable is unreasonable and does not adapt to the local climate, the optical cable will have potential safety hazards and its service life will also be affected. Therefore, each ADSS optical cable project must be strictly designed with professional software according to the natural environment and span of the optical cable to ensure that the optical cable has sufficient mechanical strength.