Offshore Electricity Infrastructure in Europe - European Wind Energy ...

Key Assumptions and Scenarios
Current technology. When considering the connection
of the larger more distant offshore wind farms, the
Voltage Source Converter (VSC) HVDC technology also
becomes important.
Compared to High Voltage Alternating Current technologies
and even the Current Source Converter
(sometimes called Line Commutated) HVDC technology,
the VSC technology is relatively immature in
terms of operating experience. The first onshore application
of VSC technology was the 50 MW Gotland
link (Sweden) commissioned in 1999, and the first offshore
application was the 84 MW Troll A link (Norway)
commissioned in 2005. Hence this technology has yet
to be proven over the expected lifetime of an offshore
wind farm or interconnector installation.
Despite this lack of experience, the technical advantages
that the VSC equipment provides for the
connection and transmission of bulk power in the
offshore environment means that the VSC equipment
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will be the transmission technology of choice for large,
distant offshore wind farms. It is for this reason that
the majority of the offshore grid designs analysed in
this report is based on VSC technology.
However, current experience shows that the supply
chain bottlenecks for the main components of HVDC
technology can slow down the development of offshore
wind farm connections. Therefore for singular
cases it might be necessary to fall back upon AC connection
concepts until the supply chain is fully able to
deliver the requested equipment on time.
OffshoreGrid – Final Report