Submarine power cable

From Wikipedia, the free encyclopedia

Submarine power cables are cables for electrical power running through the sea, below the surface.

For transmission of large amounts of electric power through submarine cables, direct current(DC) is preferred, because DC cables require less reactive power than submarine AC cables. As well, for three phase AC-cables three conductors are necessary, while for DC only 1 or 2 conductors are required.

A DC system may use the ground and seawater as a return path for current. However, this cannot be always practiced because of disturbances to magnetic compass systems on vessels crossing the cable and because of ecological effects of electrochemical reactions at the electrodes.

The length of AC cables is restricted by the capacitance between the active conductors and the surrounding earth (or water). If the cable were to be made long enough, the reactive power consumed by the cable would take up the entire current carrying capacity of the conductor, so no usable power would be transmitted.

[edit] Submarine cables for AC

[edit] Submarine cables for DC

[edit] See also