Classification of power cables

Classified by voltage level
According to voltage level, it can be divided into medium and low voltage power cables (35 kV and below), high voltage cables (110 kV and above), ultra-high voltage cables (275-800 kV), and ultra-high voltage cables (1000 kV and above). In addition, it can also be divided into AC cables and DC cables according to the current system.
Classified by insulation material
1. Oil immersed paper insulated power cables are power cables that use oil immersed paper as insulation. Its application history is the longest. It is safe and reliable, with a long service life and low price. The main drawback is that the laying is limited by the drop. Since the development of non drip impregnated paper insulation, the problem of drop limitation has been solved, allowing oil impregnated paper insulated cables to continue to be widely used.
2. The insulation layer of plastic insulated power cables is extruded plastic power cables. Commonly used plastics include polyvinyl chloride, polyethylene, and cross-linked polyethylene. Plastic cables have a simple structure, convenient manufacturing and processing, light weight, convenient laying and installation, and are not limited by laying height. Therefore, it is widely used as medium and low voltage cables and has a trend of replacing adhesive impregnated oil-paper cables. Its biggest drawback is the presence of dendritic breakdown, which limits its use at higher voltages.
3. The insulation layer of rubber insulated power cables is made of rubber and various additives, which are thoroughly mixed and extruded onto the conductive wire core, and then heated and vulcanized. It is soft and elastic, suitable for occasions with frequent movement and small bending radius during laying.
Commonly used insulation materials include natural rubber styrene butadiene rubber mixture, ethylene propylene rubber, butyl rubber, etc.
Classified by voltage level
1. Low voltage cable: suitable for fixed installation on transmission and distribution lines with AC 50Hz and rated voltage of 3kV and below for power transmission.
2. Medium and low voltage cables: (generally referring to 35KV and below): PVC insulated cables, polyethylene insulated cables, cross-linked polyethylene insulated cables, etc.
3. High voltage cables: (generally 110KV and above): polyethylene cables and cross-linked polyethylene insulated cables, etc.
4. Ultra high voltage cable: (275~800KV).
5. Ultra high voltage cables: (1000KV and above).