The Italy-Greece HVDC link consists in a mono-polar link with sea return, with a rated voltage of 400kV, a rated current of 1250A and a rated power of 500MW (guaranteed at the inverter side), which can flow in both directions between Galatina (Italy) and Arachthos (Greece).
The HVDC link includes:
- Two conversion systems - from 400kV AC, 50 Hz to 400kV DC - located in the Galatina and Arachthos stations which include power transformers, smoothing reactor, filters;
- A land DC cable at 400kV DC running on about 43km between Galatina and Otranto in Italy;
- Another short section of land DC cable (less than 1km) at Aetos in Greece;
- A submarine DC cable of 163km, between Otranto and Aetos, crossing the north side of Corfu island;
- An over-head DC line along the 110 km between Aetos and Arachthos station in Epiro;
- Two submarine electrodes and related ground connections at the Italian and Greek coasts.
A fault had been located by TDR from Galatina station, at about 17km from Otranto landing point, on the Italian shelf, at about 100m water depth.
Prysmian Group has awarded Assodivers Group the submarine repair operations and protection scope.
Vessel / Equipment used
- Aethra (Repair works)
- Astrea (Protection works)
- AssoJet III
The repair activities included :
- Spare cable loading into drum and transfer to Brindisi
- Fault location identification and cable de-burial
- Cut and sealing
- Repair operations
The protection activities included :
- Transit to Brindisi to prepare for works commencement
- PLB works
- Post jetting survey