By Renewable Energy Focus staff

Siemens will connect the offshore wind farm, which is located west of the island Sylt with consortium partner Prysmian Powerlink, an Italian cable manufacturer.

DanTysk will consist of 80 Siemens wind turbines and will have a total operating capacity of 288 MW.

The transmission links for the offshore wind farm will be of the high voltage direct current (HVDC) variety using 160 km of subsea cables and 45 km of underground cables.

The grid connection is set to be ready for operation by early 2014.

The SylWin cluster transmission link will be able to transmit up to 846 MW as more offshore wind farms are connected.

The HVDC system

Siemens’ HVDC system, HVDC Plus, will be installed on an offshore substation platform alongside transformers and gas-insulated high voltage switchgear. The AC power from the wind turbines will be converted to DC power at the platform, which will be located next to the offshore wind farm.

The DC power will be brought to a transmission voltage of 320 kV before being transported to Büttel in the estuary of the Elbe, which is the grid feed-in point on the cost where the power will be converted back to AC.

Siemens says HVDC is necessary for cable links longer than 80 km because a large amount of the energy in form of reactive power would be lost in a three-phase line of such a length. Siemens’ HVDC Plus features converters based on voltage-sourced converter technology in modular multilevel converter design (VSC MMC). This is said to reduce system complexity.

The contract follows Siemens’ grid connection of the offshore wind farm clusters BorWin2 and HelWin1.