Aerial bundled cables are a new power transmission method between overhead conductors and underground cables. They have the main characteristics of high power supply reliability, good power supply security, convenient erection and maintenance, and reasonable economy. The use of overhead cables can greatly reduce various short-circuit faults, greatly reduce personal electric shock casualties, and reduce the maintenance and repair work of the line.
Aerial bundled cable definition
Aerial bundled cables (full name overhead insulated cable) is an overhead wire equipped with an insulation layer and a protective sheath. It is a special cable manufactured by a production process similar to cross-linked cables. It is a new power transmission between overhead wires and underground cables. Way.
Aerial bundled cable advantage
- It can simplify the structure of line poles and towers, and can even be laid along the wall, which not only saves line materials, but also beautifies the city streets.
- It is conducive to improving and enhancing the safety and reliability of the power distribution system, greatly reducing the risk of personal electric shock casualties, insulated wires can prevent phase-to-phase short circuits caused by foreign objects, reduce the number of power outages during the operation of the combined pole line, reduce maintenance workload, and improve Line power utilization.
- Save the line power loss and reduce the voltage loss, the line reactance is only 1/3 of the ordinary bare wire line reactance.
- Go deep into the load center at high voltage to improve voltage quality and reduce power loss.
- The space occupied by the overhead line is saved, and it is convenient for the overhead line to pass through the narrow passage. The line corridor is reduced, compared with the overhead bare wire, the line corridor can be reduced by 1/2.
- Reduce wire corrosion, thereby improving the service life of the line and the reliability of power distribution.
- Reduce the insulation requirements for line supports and increase the number of lines on the same pole. Due to the improvement of the technical status of the line, the maintenance workload is reduced, the maintenance cycle is extended, and the time of power outage due to maintenance is reduced.
Aerial bundled cable disadvantage
- The allowable current carrying capacity of high-voltage insulated overhead wires is smaller than that of bare wires, because after the plastic layer is added, the heat dissipation of the wires is poor, and the general shape of overhead insulated wires should be higher than usual. Matched to 95mm2.
- The wire diameter of the high-voltage insulated overhead wire is relatively large, and with the addition of a plastic sheath, the wire diameter is one grade larger than that of the steel-cored aluminum stranded wire with the same cross-section. Although insulated wires have many advantages, the unit cost is higher than that of bare wires, about twice as high for medium-voltage lines, and about 25% higher for low-voltage lines.
Overhead insulated cable products are a new series of products for overhead transmission lines to transmit electric energy, and are preferred for power grid construction and transformation of 10kV transmission lines. It is the most suitable series of products for line maintenance and safety. Annealed copper core products are suitable for transformer lower leads.