US 12,258,940 B2
Method for controlling the rotor speed of a wind turbine
Johannes Frommann, Hamburg (DE); Enno von Aswege, Großefehn (DE); Ulf Schaper, Staffhorst (DE); and Gnanasekaran Rengaraj, Tamil Nadu (IN)
Assigned to Wobben Properties GmbH, Aurich (DE)
Filed by Wobben Properties GmbH, Aurich (DE)
Filed on Jun. 8, 2022, as Appl. No. 17/835,615.
Claims priority of application No. 21179056 (EP), filed on Jun. 11, 2021.
Prior Publication US 2022/0397092 A1, Dec. 15, 2022
Int. Cl. F03D 7/02 (2006.01)
CPC F03D 7/0276 (2013.01) [F03D 7/0224 (2013.01); F03D 7/0284 (2013.01); F05B 2270/32 (2013.01); F05B 2270/327 (2013.01); F05B 2270/328 (2013.01); F05B 2270/335 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for controlling a rotor speed of a rotor of a wind turbine at rated or curtailed operation conditions the rotor being an aerodynamic rotor having one or a plurality of rotor blades, the wind turbine comprising a tower and a generator, the method comprising:
using a pitch control to provide a pitch angle set value, the pitch angle set value being dependent on an actual rotor speed for setting a pitch angle of the rotor blades,
using a main control to provide a main power or torque set value for controlling the power or torque of the generator, and
using an additional control to provide an additional power or torque set value, the additional power or torque set value being dependent on the actual rotor speed,
wherein the additional power or torque set value is provided as an offset value and is added to the main power or torque set value, and
wherein:
the additional power or torque set value is calculated depending on a control deviation of the rotor speed, and/or
a maximum power control provides a maximum power value as a varying value for limiting an output power of the generator, and the maximum power value is calculated depending on:
a predetermined power limit value, and
a predetermined reference duration,
to provide for the reference duration an average power reaching or at least not exceeding the predetermined power limit value.