Two 700 MVA power transformers for Dolwin3 project successfully installed on the platform

2015-9-27 Alstom

 Alstom and the German-Dutch transmission system operator TenneT have set another key milestone in the North Sea offshore grid connection project - 'Dolwin3'. Two 700 MVA power transformers were successfully delivered and installed on the platform with its base in the Warnemüde shipyard in Germany, which is operated by Nordic Yards. The offshore grid connection project DolWin3 will provide clean energy by connecting the North Sea wind farms to the mainland. The project is expected to be completed in 2017.

The transformers weigh 496 tonnes each including some 120 tonnes of oil as cooling agent. They were designed and built by Alstom specifically for the DolWin3 converter project at its Mönchengladbach plant in Germany. Even during routine inspections, one transformer ensures that the converter platform transmits the generated energy uninterruptedly. The transformers were transferred on a 1,200-km-long journey by road, river and sea to be finally installed on the platform in Warnemünde. There they are located in rooms specially designed with special corrosion protection against the harsh and aggressive offshore climate.

"The 900 MW wind energy DolWin 3 is the largest HVDC-converter platform with the highest capacity that is built at Nordic Yards.

"The two power transformers are core components of the DolWin 3 offshore converter platform... This installation is the prerequisite for completion of the platform's steel structure by Nordic Yards and the onward completion of the project" said Gerhard Seyrling, Vice President Alstom Grid, Region Central & Eastern Europe and Russia.

The project will use direct current technology with Voltage Source Converters (VSC) (±320 kV, 900 MW) to deliver the energy generated at sea to the mainland.

Source: Alstom