Environmental Engineering Reference
In-Depth Information
Leitner in Italy. The main diferences in the DD machines can be
found in the bearings. Basically the hub is connected to the blades
in a rigid way as the rotor is to the generator, and is carried by two
roller bearings. In Fig. 19.10, the bearing concept introduced by
Enercon can be seen—the rotor hub is carried by a small locating
bearing in the front and a bigger floating bearing in the back.
Therefore the hub bolted to the rotor can be described as “flying”,
stored slightly in front of the two bearings.
Figure 19.10
Enercon concept drawing (Image: author).
A further innovation to simplify the direct drive-bearing
concept was introduced by Lagerwey (Fig. 19.11). A bearing
that takes overhanging bending moments from the rotor in one
unit consisting of three rows of cylindric rollers (Rothe Erde) or
double row tapered rollers (SKF, FAG).
It was a 2.5 MW Vensys turbine that was first equipped with
a Nautilus bearing from SKF in 2006, which was later used in
most of the new developments as well as in ofshore turbines by
Siemens from 2009 and 2010. A totally new bearing concept was
suggested by the wind researchers from Saarbrücken in 2006
and later used in a 2 MW project in China (Fig. 19.12).
Search WWH ::
Custom Search