03-07-2012, 02:47 PM
HVDC TRANSMISSION
HVDC TRANSMISSION.ppt (Size: 8.19 MB / Downloads: 370)
At the beginning of 20th century, DC (Direct Current) was superseded by AC (Alternating Current) for large-scale electrification. DC power did nevertheless survive, in applications like electric traction and drives.
Today, bulk power systems are 3-phase AC, while utilization is either 1-phase or 3-phase AC.
Continental Europe is actually a single AC power system, running synchronously at 50 Hz, spanning from Portugal to Poland and Greece!
TYPICAL HVDC APPLICATIONS
Interconnection of non-synchronous AC power systems, even at different frequencies.
Power transmission over long undersea cable links, if the AC solution requires intermediate compensation.
Point-to-point, long-distance transmission of large blocks of power.
Long-distance transmission
The main shortcomings lies in the AC/DC conversion stations due to their cost, large footprint and additional energy losses
The comparison between all the above factors, dictates the convenience of AC or DC
North Africa to Italy
There are no particular shortcomings aside from the cost of submarine cables: in the first stage (say, 3000 MW power transfer) up to 3 cables per pole are needed
Other key points are:
Individuation and survey of cable routes in deep sea (see f.i. studies conducted for Sa.Pe.I. link)
Identification of suitable EHV terminals in the Italian network (several powerful nodes on the Tyrrhenian coast, from Naples to Suvereto)