QUALIFICATION TEST PROGRAM FOR THE 1000 MW- 500 kV HVDC VERYDEEP WATER SUBMARINE CABLE INTERCONNECTION BETWEEN SARDINIA ISLAND AND ITALIAN PENINSULA (SA.PE.I)

摘要

The SA.PE.I HVDC link consists of a bi-polar link with a rated voltage of 500 kV and a rated power of 1000 MW, which allows energy to flow in both directions between Fiume Santo (Sardinia) and Latina (Lazio, Italy Mainland). The link is based on a grid commuted twelve pulse thyristor bridge and is conceived to operate with an emergency sea return in case of outage of one cable or converter pole. At time of writing the first pole is foreseen to be completed by Year 2008, and the complete bi-pole by Year 2010. The link Owner is TERNA, the Italian Transmission System Operator (TSO) and the principal owner of the National Transmission Grid; engineering support is provided by CESI. Prysmian is in charge of Engineering, Qualification, Procurement and Construction for the whole cable interconnection and electrode system. The submarine portion is approx 425 km long and develops for about 55% in very deep waters, up to the maximum depth of 1620 m, a depth never reached before for any high-power cable interconnector. The paper describes the extensive Qualification Program carried out on the three cable designs (deep water, medium/low water and land cables) and all relevant accessories (joints, terminations, etc.), including mechanical and electrical tests according to CIGRE recommendations. Additional tests were carried out to verify all the system components under special service conditions, in particular to confirm the ability of the system to withstand repeated polarity reversals. The Qualification Program also included two complete sea trials, carried out on actual cables prototypes (for a length of more than 10 km), in deep and in medium/low water depth, as well as studies and tests for the electrodes and the relevant feeding cables.