There is provided a method (40) of correcting blade pitch in a wind turbine (10) having a tower (12) and a plurality of rotor blades (18). The method (40) comprises: receiving (410) sensor output data from one or more wind turbine sensors (141), the sensor output data including data indicative of excitation of the tower (12) for a plurality of different pitch angles of a particular one of the blades (18); determining (420) a corrected pitch reference of the particular blade (18), the corrected pitch reference corresponding to a minimum tower excitation based on the received sensor output data; and, sending (430) the corrected pitch reference to a pitch actuator system (24) of the particular blade (18).

A method of operating at least one wind turbine including: receiving a first signal which is indicative of a level of a remuneration for electrical energy, which is fed currently and/or in the future into a grid to which the wind turbine is connected, producing a control signal dependent on the first signal, and controlling the wind turbine with the control signal for generating power of the wind turbine, that is dependent on the control signal. A wind turbine and a central control for carrying out such a method and a system comprising a central control and a plurality of wind turbines.

A method for controlling a wind turbine may generally include operating the wind turbine at an initial power output that is greater than a rated power output associated with the wind turbine. The wind turbine may have an anticipated operational life at the rated power output. In addition, the method may include decreasing a power output of the wind turbine over time in order to maintain an actual operating life of the wind turbine substantially equal to or greater than the anticipated operational life. A final power output of the wind turbine at an end of the anticipated operating life may be less than the rated power output.

A wind park controller and control method for a wind park (10) are described. The wind park comprises a plurality of wind turbines (20) and an Energy Storage System (24) connected to one another by means of a low voltage power network (22, 25), which is in turn coupled to the grid. The controller determines a number of operating parameters of the wind turbine gearbox or drive train, and calculates a gearbox or drive train health metric. This can include a measure of the gearbox lifetime. The controller also determines one or more power characteristics of the wind turbine generator or the point of common coupling (26) to determine a power mismatch indication. Based on the power mismatch indication and said gearbox or drive train health metric, the controller determines a power command for the Energy Storage System and wind turbines based to improve the gearbox health and lifetime.

A method for controlling a wind energy farm is disclosed. A wake state of the wind energy farm is determined, including determining wake chains defining wake relationships among the wind turbines of the wind farm under the current wind conditions. For at least one of the wind turbines of the wind energy farm, a lifetime usage is estimated, based on an accumulated load measure for the wind turbine. In the case that the estimated lifetime usage is below a predefined lifetime usage limit, the wind turbine is operated in an overrated state, while monitoring wake effects at each of the wind turbines. In the case that a downstream wind turbine detects wake effects above a predefined wake threshold level, at least one wind turbine having an upstream wake relationship with the downstream wind turbine is requested to decrease the generated wake, e.g. by decreasing power production.

A control arrangement for a variable-speed wind turbine includes a loading analysis module configured to analyse a number of environment values to establish whether the momentary wind turbine loading is lower than a loading threshold when the rotational speed of the aerodynamic rotor has reached its rated value; and a speed boost module configured to determine a speed increment for the rotational speed of the aerodynamic rotor if the wind turbine loading is lower than the loading threshold.

The present subject matter is directed to a system and method for operating a wind turbine. The method includes determining an actual operating time for one or more wind turbine components at multiple power levels; determining a corresponding wind condition for each of the operating times at each power level; estimating a loading condition acting on the one or more wind turbine components at the multiple power levels and the corresponding wind conditions; estimating an accumulated fatigue life consumption of the one or more wind turbine components based at least partially on the operating times and the estimated loading conditions; and, operating the wind turbine based on the accumulated fatigue life consumption.

The present invention relates to a method of operating a wind farm comprising an upstream and a downstream turbine, wherein the upstream turbine is operated with current operation parameters under current wind conditions, wherein the method comprises the steps of: receiving future wind conditions for a time period for the wind farm, and evaluating required operation parameters for minimising wake effect of the downstream turbine under the future wind conditions, and determining a cost coefficient for changing the operation parameters to required operation parameters under consideration of fatigue effect of the wind turbine, calculating power productions P.sub.o and P.sub.c, in the predetermined time period, by the wind farm if operated with the current operation parameters under the current wind conditions and if operated with the required operation parameters under the future wind conditions, respectively, and operating the upstream turbine with the required operation parameters if the cost coefficient is lower than a cost that would be obtained by a power production increment P.sub.c-P.sub.o.

Method of operating a wind turbine in response to a wind speed, the wind turbine having at least a rotor with a plurality of blades and a generator comprising a generator rotor and a generator stator, the method comprising, at wind speeds above a first wind speed, increasing the pitch angle of the blades and reducing the rotor speed with increasing wind speed, said first wind speed being superior to the nominal wind speed; wherein at a second wind speed, the speed of the generator rotor is equal to the synchronous generator rotor speed, said second wind speed being superior to said first wind speed; and wherein at wind speeds superior to said second wind speed, the speed of the generator rotor is lower than the synchronous generator rotor speed.

Generating a control schedule for a wind turbine, the control schedule indicating how the turbine maximum power level varies over time. Generating the control schedule includes determining a value indicative of the current remaining fatigue lifetime of the turbine, or one or more turbine components, based on measured wind turbine site and/or operating data; applying an optimisation function that varies an initial control schedule to determine an optimised control schedule by varying the trade off between energy capture and fatigue life consumed by the turbine or the one or more turbine components until an optimised control schedule is determined.