GOLD Winergy HybridDrive with journal bearings and optional EESG
Runner up last year with its 3-8MW HybridDrive drivetrain platform, Winergy has since introduced its optimised 3.3MW medium-speed model, utilising some of the built-in design reserves that come from its initial 3MW unit.
HybridDrive systems comprise a semi-integrated gearbox and generator combination joined by flange connections.
New with this model is the journal bearing version, featured in the two-stage planetary gearbox and generator. It can also be fitted with an electrically excited synchronous generator instead of a permanent magnet generator on request.
There is a growing interest in gearboxes incorporating journal bearings as operators look for improved reliability and longer operating life. They are finding favour in applications that range from stone crushers and earth-moving equipment to ship propulsion, but their use in wind turbines has been limited so far. The best known application has been the Multibrid-type turbines, especially Areva's M5000 series.
Journal bearings combine compactness with high resistance to (static) impact loads and long service life. New gearbox designs using these could reduce drivetrain size and mass. Specific lubrication measures are required to ensure adequate oil film build-up in journal bearings, especially during critical cold weather and non-operating conditions.
The first production units are expected to go to a batch of 54 CleanAyr Energy 3.3MW turbines developed by W2E. A high-speed Winergy gearbox with journal bearings has been operating for the past two years in a 2MW Vestas V90 turbine in Scandinavia.