The types of submarine cables can be briefly divided into four aspects.
1. From the structure, is mainly divided into three-core submarine cables and single-core submarine cables. Low- and medium-voltage lines use mostly three-core submarine cable, and high-voltage lines use mostly single-core submarine cable.
2. From a functional point of view, the submarine cable is divided into a submarine communication cable and a submarine power cable. Submarine communication cable is mainly used for communication business, expensive, but with a high degree of confidentiality. Submarine power cable is mainly used for underwater transmission of high-power electricity, and the role of the underground power cable is the same, but the application of the occasion and the way of laying are different.
3. From the insulation composition, is divided into oil-filled insulated submarine cable and extruded plastic insulated submarine cable.
4. From the load type, divided into DC submarine cable and AC submarine cable, DC submarine cable is characterized by small losses, and easy to achieve long-distance transmission. But the application of DC submarine cable is not a rich experience, DC converter stations and other supporting construction costs are high, and AC submarine cable loss, but the operation and maintenance technology is mature, and supporting construction costs are small. So the cable line designers usually have to make technical and economic trade-offs to achieve maximum benefits.
The use of submarine cable
Submarine communication cables are mainly used for long-distance communication networks, typically for long-distance between islands, cross-sea military facilities, and other more important occasions. Submarine power cables are laid at much shorter distances compared to communication cables. Mainly used between land islands, across rivers or harbors, from land to connect the drilling platform or drilling platform interconnection, etc.
The current domestic and international submarine cable has broad market and application prospects, mainly reflected in the following markets.
1. Coastal cities and islands market
Submarine cable is a significant means of transmission of electricity and communications between coastal islands and cities. Between coastal cities, islands, and islands and the mainland between the required photoelectric composite submarine cable and submarine cross-linked cable in 2006 amounted to about 800 km, to 2020 is expected to demand more than 3000 km.
2. Offshore oil platform with submarine cable market
It is understood that the amount of cable on each type of offshore oil platform is: 150 km jack-up platform, 180 km semi-submersible platform, oil recovery platform 200 km, production platform 200 km, and living platform 100 km.
3. Rivers, lakes, and another underwater cable market
Due to the need to transform rivers, lakes, and reservoir dams, underwater cables are being used more and more widely.
4. Offshore wind power and power transmission with submarine cables
Construction of offshore wind farms is an important direction of international new energy development, and will also be the development of the wind power industry, “the direction of the direction”. For the submarine cable, its application in offshore wind power generation and transmission has a broad market prospect.