The tests will last for several weeks and the platform is expected to go into controlled operation early in 2015.
Siemens installed the BorWin2 HVDC platform, located about 100km northwest of the North Sea island of Borkum, in April 2014.
Italian cable specialist Prysmian installed two 200km long submarine cables.
The BorWin2 link fed electricity into the grid for the initial time in first tests carried out in early September 2014 following connection of the Global Tech 1 wind farm.
TenneT expects that the link will be used at only 50% capacity for the next two years.
Siemens will use HVDC technology, deployed both on the offshore platform and in the land-based converter station in Diele, East Frisia, to bring the wind-generated energy to land.
The wind-generated power will initially be transported as alternating current to the BorWin2 converter platform, which provides enough energy for about 800,000 households.
The alternating current will then be converted into direct current, and brought to land through submarine cables.
The land-based station converts the direct current back into alternating current and feeds it into the high-voltage grid.
Siemens is currently implementing five North Sea grid connection projects for TenneT.
Image: Siemens installed the offshore platform for the BorWin2 grid connection at sea in April 2014. Photo: Courtesy of Siemens.
