What is an All-Dielectric Self-Supporting (ADSS) Cable?

As we all know, ADSS optical fiber cable and OPGW optical cable belong to power cables. They make full use of the unique resources of the power system and closely integrate the grid structure with construction. They are economical, reliable, and fast. , safe. The power special optical cable is less likely to be damaged by external force and has high reliability. Although its own cost is relatively high, its construction cost is low. ADSS fiber optical cables and OPGW optical cables are installed at different voltage levels of various power towers. Compared with ordinary optical cables, their mechanical, optical, and electrical characteristics have special requirements.

ADSS optical cables are mainly used for information transformation of existing lines, mostly for 220kV, 110kV, and 35kV transmission lines. Mainly to meet the requirements of large vertical and long-span transmission lines. The characteristics of ADSS optical cable are:

1. ADSS cable has small diameter and light weight, which can reduce the impact of ice and wind on the optical cable, and has little impact on the strength of the iron tower;

2. ADSS adopts new materials and smooth shape design to provide superior aerodynamic characteristics;

3. Corrosion-resistant ADSS cables can reduce the electrical corrosion of cables caused by high-voltage induced electric fields;

4. The expansion rate of ADSS remains unchanged in a large temperature range, and has stable optical properties at extreme temperatures;

5. The theoretical value of fiber tension in ADSS is zero;

6. The ADSS cable is a fully insulated structure, and both installation and line maintenance can be operated live, thereby greatly reducing power failure losses.

ADSS optical cable uses high-strength aramid yarn as the tensile element in the production process of body armor. Due to the selection of high-strength, light-weight and high-tech materials, the weight of ADSS optical cable is only one-third of that of ordinary optical cable. The size is small, the additional load added by the tower is small, and it can be directly hung on the appropriate position of the power tower, and the maximum span can reach 1500m. The cable is made of non-metallic material with good insulation performance, which can avoid lightning strikes and power line failures, and will not affect the normal operation of the cable; the outer sheath is impregnated with neutral ions, so that the cable has strong anti-electric corrosion performance, which can ensure The service life of cables in strong electric fields; Using existing power poles and towers, construction without power failure is possible, and poles are used to erect power lines, which can reduce project cost.

ADSS fiber cables work in high-voltage transmission lines, and there is a strong electric field around them, and the phenomenon of electrical corrosion often leads to damage or even damage to the optical cables. Current solutions include:

1. The space potential of the suspension point of the control cable shall not exceed 15kV for 110kV, and not exceed 20kV for 220kV.

2. Tracking-resistant coatings are preferred for lines with different voltage levels, and tracking-resistant materials must be used for lines with 110kV and above.

3. For lines of 110kV and above, corona coils can be considered to effectively reduce the surface electric field of hardware and cables, and reduce leakage current.

4. For 220kV and above lines and lifting point field strength towers, anti-vibration hammers are much safer for cables to climb and corrode the outer surface than anti-vibration whips.