The vast majority of wind turbine manufacturers use gearboxes that change the speed and torque between the wind rotor and the generator. The rotor shaft turns slowly with a very high torque, and the generator turns very fast with a low torque.
Due to the overload of the power grid, the wind turbine comes to a standstill more often. The cooling of the gearbox caused by the standstill ensures that air from the environment is “breathed in”. If this air contains dirt and moisture, this leads to oil saturation via condensation in the gearbox. Possible damage, such as corrosion or cavitation, etc., can lead to high maintenance and unplanned downtime costs for the entire plant.