4 ms·
I think one of the very few remaining applications of variable-speed gearboxes are wind generators with no converter. But this in itself is rare, because it may
by dom0 9y ago
I think one of the very few remaining applications of variable-speed gearboxes are wind generators with no converter. But this in itself is rare, because it may be more reliable (?), but also less efficient than the power electronics... (afaik off-shore wind generators are going completely gearless).
- Animats 9y agoWind turbine gearboxes are all fixed ratio, as far as I can tell. The blade pitch is adjusted to maintain a constant speed in synchronous machines. Ones with AC-DC-AC converters don't need to do that. There's also something called a "doubly fed machine", which is a 3-phase generator where the field windings are actively driven to rotate the magnetic field to compensate for minor speed variations of the rotor. Wind turbine gearboxes take a lot of pounding as the wind shifts. Wear is a big problem and not fully understood. The trend is toward gearless systems. Transmission repair atop a wind turbine is not fun. Power semiconductors are good enough that it's easier to deal with this electrically.
- dom0 9y agoIIRC Voith developed these... I'm in no way an expert about these, but I'd guess that going gearless and using a slow-running generator would have the advantage that you get a much longer and fatter shaft to put bearings on.