Wind Energy – Converter Platforms
Dragados Offshore will develop, in consortium with Siemens Energy, the HVDC converter platforms of both the DolWin4 and BorWin4 HVDC grid connection projects for Amprion Offshore.

The project consists of two 900 megawatt converter systems for the transmission of electrical energy, part of Germany’s Energy Transition, in which the Hanekenfähr grid access point was seen as the ‘technically most expedient and cost-effective solution’ for the NOR-3-2 (DolWin4) and NOR-6-3 (BorWin4) connection systems.
Amprion is the transmission system operator responsible for this area and for both systems.
The grid connection systems for DolWin4 and BorWin4 are set up as point-to-point HVDC transmission systems, each executed as a symmetrical monopole. The offshore stations are set up in the relevant cluster for the Offshore Wind Farms to be connected. Both the HVDC transmission converters and the necessary auxiliary systems are installed at these stations.
The OWFs are connected to both offshore stations via 66 kV AC direct connection systems and convert the power to 320 kV DC voltage for transmission to shore.
The two HVDC onshore stations for DolWin4 and BorWin4 are connected to the Hilgenberg switchgear as well as being linked to the 380 kV link that is to be built to the grid access point at Hanekenfähr for the AC transmission grid.
With a total transmission capacity of 1.8 GW, these converter stations will be sufficient to supply the electricity for a major city like Hamburg of 1.8 million people.
Dragados Offshore is responsible for providing the offshore platforms, including detail design and engineering, procurement, fabrication, construction, load out, transportation, installation and hook-up of the offshore platform, and installation and commissioning of its platform systems.
The HVDC systems, as well as the complete onshore converter stations, are the scope of work of partner Siemens Energy.