Greenlink will use high voltage direct current voltage source converter (HVDC VSC) technology to link the two power systems. HVDC has been selected over an AC connection, because AC is technically difficult over this distance. VSC technology has the main benefit that it reduces the size of the converters (when compared to similar technologies).
The Greenlink Interconnector converter station
The indicative converter station site footprint would be circa. 1.85 hectares (185m x 100m). A converter station consists of various components. These include a converter hall, converter transformers, AC switchgear and busbars, harmonics filters, lightning towers, ancillary plant such as cooling bank and diesel generators, and a control building. Typically the tallest components are the lightning towers at circa 26 metres high and the converter hall, which could be up to 21 metres high at its apex. The converter hall and main building are usually one continuous building with height difference. The layout of the converter station and final dimensions will depend on the local terrain, physical constraints, the results of environmental surveys, consultations and the supplier’s technical requirements.