A method for operating a wind turbine wherein a parameter for a wind hitting the wind turbine is determined from present values for the generator speed and/or the wind speed at each point in time (t). A temporal change variable is formed for the parameter at each point in time (t). For the temporal change variables, which occurred in a past time interval, the third and/or fourth statistical moment is calculated for a distribution of the temporal change values in the time interval. If at least one of the statistical moments exceeds a predetermined value, then a detection signal is set for an extreme gust, which triggers one or both of the steps: increasing a setpoint value for the blade pitch angle starting from an actual value thereof, and reducing a setpoint value for the generator speed starting from an actual value thereof.

A method of operating a wind turbine power generating apparatus includes a step of obtaining a wind direction of a wind; a step of obtaining at least one of a wind velocity of the wind or an index of turbulence degree of the wind velocity; and a step of selecting an operation mode of the wind turbine power generating apparatus from among a plurality of operation modes including a normal operation mode and at least one load-suppressing operation mode in which a load applied to a wind turbine blade is smaller than in the normal operation mode, on the basis of whether the at least one of the wind velocity or the index of turbulence degree is at least a threshold. The threshold of the at least one of the wind velocity or the index of turbulence degree is variable in accordance with the wind direction.

A method for damping an oscillation of a tower of a wind turbine is disclosed, wherein a pitch angle of each of the one or more rotor blades is individually adjustable, the method comprising damping the oscillation of the tower by pitching each rotor blade individually according to tower damping pitch control signals, wherein each tower damping pitch control signal comprises a first periodic component, where a first frequency of the first periodic component corresponds to a frequency difference between a tower frequency of the oscillation of the tower and a rotor frequency of a rotation of the rotor, and where a second periodic component has been reduced or removed. A second frequency of the second periodic component corresponds to a frequency sum of the tower frequency and the rotor frequency.

A noise-reduction device for a wind turbine and the wind turbine applied thereof are introduced. The noise-reduction device has a body. The body has a connection portion and a spoiler. The connection portion is concavely disposed on one side of the body and corresponds in shape to the wind turbine's blade so as to be fixed to a confronting edge of the wind turbine blade. The spoiler is disposed on the opposing side of the body. As soon as the wind turbine blade is driven by wind, the spoiler stirs air and guides the air across two sides thereof. When guided by the spoiler, airflows turn into vortexes on the wind turbine blade; hence, the chance that the wind turbine will stall and generate noise is greatly reduced.

A method for operating a wind turbine wherein a parameter for a wind hitting the wind turbine is determined from present values for the generator speed and/or the wind speed at each point in time (t). A temporal change variable is formed for the parameter at each point in time (t). For the temporal change variables, which occurred in a past time interval, the third and/or fourth statistical moment is calculated for a distribution of the temporal change values in the time interval. If at least one of the statistical moments exceeds a predetermined value, then a detection signal is set for an extreme gust, which triggers one or both of the steps: increasing a setpoint value for the blade pitch angle starting from an actual value thereof, and reducing a setpoint value for the generator speed starting from an actual value thereof.

A method of operating a wind turbine power generating apparatus includes a step of obtaining a wind direction of a wind; a step of obtaining at least one of a wind velocity of the wind or an index of turbulence degree of the wind velocity; and a step of selecting an operation mode of the wind turbine power generating apparatus from among a plurality of operation modes including a normal operation mode and at least one load-suppressing operation mode in which a load applied to a wind turbine blade is smaller than in the normal operation mode, on the basis of whether the at least one of the wind velocity or the index of turbulence degree is at least a threshold. The threshold of the at least one of the wind velocity or the index of turbulence degree is variable in accordance with the wind direction.

A noise-reduction device for a wind turbine and the wind turbine applied thereof are introduced. The noise-reduction device has a body. The body has a connection portion and a spoiler. The connection portion is concavely disposed on one side of the body and corresponds in shape to the wind turbine's blade so as to be fixed to a confronting edge of the wind turbine blade. The spoiler is disposed on the opposing side of the body. As soon as the wind turbine blade is driven by wind, the spoiler stirs air and guides the air across two sides thereof. When guided by the spoiler, airflows turn into vortexes on the wind turbine blade; hence, the chance that the wind turbine will stall and generate noise is greatly reduced.

A method for damping an oscillation of a tower of a wind turbine is disclosed, wherein a pitch angle of each of the one or more rotor blades is individually adjustable, the method comprising damping the oscillation of the tower by pitching each rotor blade individually according to tower damping pitch control signals, wherein each tower damping pitch control signal comprises a first periodic component, where a first frequency of the first periodic component corresponds to a frequency difference between a tower frequency of the oscillation of the tower and a rotor frequency of a rotation of the rotor, and where a second periodic component has been reduced or removed. A second frequency of the second periodic component corresponds to a frequency sum of the tower frequency and the rotor frequency.