In submarine electricity cable development so far, the structure has been designed to make a variety of exploration and experimentation, the main structure includes the following types:

1. Impregnated Paper-Covered Submarine Cable.
Suitable for not more than 45kV AC and not more than 400kV DC lines. At present, it is only installed at a water depth of 500 m or less.

2. Oil-Filled Submarine Cable.
Use the method of supplemental pregnancy to eliminate the air gap in the cable. When the cable temperature rises, the imp regnant expands, the pressure inside the cable increases, and the demon regnant flows into the oil supply tank. When the cable cools, the pregnant shrinks, the pressure inside the cable decreases, and the pregnant in the oil supply tank flows into the cable again, preventing the generation of air gaps. So it can be used for 110 kV and above lines. Laying in water depths up to 500 m.

3. Inflatable (Pressure-Assisted) Submarine Cable.
Using impregnated paper bags of inflatable cable over oil-filled cable is more suitable for the longer submarine cable network. But because of the need to operate under deep water using high air pressure, thus increasing the difficulty of designing the cable and its accessories, generally limited to a water depth of 300 m.

4. “Oil Pressure” Tube Submarine Cable.
Only suitable for several kilometers of the cable system, because the very long cable to pull into the pipe, is subject to great mechanical constraints.

5. Extruded Insulation XLPE EPR Cables.
Suitable for up to 200kV AC voltage. Ethylene propylene rubber is more resistant to dendritic phenomena and local leakage than polyethylene, making submarine cables function more effectively.