Provided is a wind park, a wind park controller, and a method for controlling a first wind turbine of a plurality of wind turbines of a wind park, wherein a second wind turbine of the plurality of wind turbines can be affected by a wake region caused by the first wind turbine which is positioned upstream of the second wind turbine. A current yaw state is determined and is selected from at least one of: a) an actual rotor yaw misalignment angle of the first wind turbine, wherein the actual rotor yaw misalignment angle is an angle between a rotating axis of a rotor of the first wind turbine and a current wind direction at the rotating axis upstream of the first wind turbine, b) an identifier representing whether the actual rotor yaw misalignment angle is either in a range of positive yaw misalignment angles or of negative yaw misalignment angles.

A method for operating a plurality of wind turbines, in which a first current estimated wind value is derived from operating parameters of a first wind turbine, and in which a second current estimated wind value is derived from operating parameters of a second wind turbine. A prediction model is applied to derive, from the first current estimated wind value and the second current estimated wind value, a wind prediction, applicable to a future time point, for a third wind turbine. The wind prediction is processed in a controller, in order to generate a control signal for the third wind turbine that is effective before the future time point. The invention additionally relates to an associated control system. The loading for particular wind turbines can be reduced in that the wind conditions are predicted for a future time point.

A method for operating a first wind turbine and a second wind turbine, the second wind turbine being located in the wake of the first wind turbine. A prediction model is fed with a current wind value of the first wind turbine, in order to predict a future time point at which the area swept by the rotor of the second wind turbine becomes partially overlapped by the wake of the first wind turbine. The second wind turbine reacts to the prediction in that a control signal is generated in order to alter the pitch angle of a rotor blade of the second wind turbine relative to the pitch angle of another rotor blade of the second wind turbine. The invention additionally relates to a control system suitable for executing the method. Implementation of the disclosed method by a control system can reduce the loading of the second wind turbine.

A wind turbine group power generation amount evaluation device includes a criterial correlation acquisition unit which acquires a criterial correlation between a target power generation amount by a target wind turbine group and a reference power generation amount by a reference wind turbine group, a set value changing unit configured to change a set value of an output control parameter of at least one of the wind turbines in the target wind turbine group, a power generation amount acquisition unit configured to acquire the target power generation amount and the reference power generation amount measured after a change in the set value, a target power generation amount estimation unit configured to calculate, an estimated value before the change of the target power generation amount, and an evaluation unit configured to evaluate a target power generation amount based on a comparison between the target power generation amount and the estimated value.

Embodiments of the present invention provide methods and apparatus for increasing turbulent mixing in the wake of at least one wind turbine. Doing so, increases efficiency of a wind turbine located in the wake by transferring energy to the wake that was lost when the wind passed through the upwind turbine. Turbulent mixing may be increased by changing the induction factor for a rotor by, for example, altering the pitch of the blades, the RPMs of the rotor, or the yaw of the nacelle. These techniques may be static or dynamically changing. Further, the different induction factors for a plurality of wind turbines may be synchronized according to a predetermined pattern to further increase turbulent mixing.

To solve the problem of a mis-calibration of a wind turbine a computer-implemented method for re-calibrating at least one yaw-angle of a wind turbine starting from an initial yaw-angle calibration of said wind turbine, based on determining a turbulence intensity estimation value (20) related to said appropriate yaw-angle (10), wherein the turbulence intensity (TI) being a ratio of wind speed deviation to average wind speed over a pre-determined period of time. Further, to solve the problem of a mis-calibration of a wind turbine a system for re-calibrating at least one yaw-angle of a wind turbine based on above re-calibration method. Further, to solve the problem of a management of a wind park below optimum a computer-implemented method for wind park optimization based on simulation calculation including turbulence intensity estimation values (20) estimating said at least one effecting wind turbine (101,102,103) to suffer from wake from said at least one effected wind turbine (100,101,102). Further, to solve the problem of a management of a wind park below optimum a wind park, including a management system for optimizing that wind park based on above optimization method. Moreover, present invention relates to a computer-readable medium comprising such methods.

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.0 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.0.

The present invention is concerned with an operation of a wind farm with a plurality of wind turbines in view of a dynamic frequency response. According to the invention, dynamic frequency support and power production for all wind turbines in a wind farm are handled concurrently in a single optimization step and taking into account wake effects within the wind farm as well as optional wind forecast information. The dynamic frequency support capability of the entire wind farm is planned in advance according to grid requirements and power system condition changes. While existing methods de-load wind turbines with a static percentage in order to supply additional power when needed, the proposed method incorporates the dynamic frequency support into the optimal operation system of wind farm.

A wind turbine comprises a nacelle, a drive shaft extending from the nacelle along a shaft axis, a plurality of turbine blades coupled to the drive shaft and extending radially relative to the shaft axis, and a first static airfoil structure coupled to the wind turbine to influence airflow exiting the plurality of turbine blades. A method of increasing wind turbine efficiency in a wind farm comprises positioning a first wind turbine having a first plurality of turbine blades at least partially upstream of a second wind turbine having a second plurality of turbine blades, producing a wake field of exit air behind the first plurality of turbine blades, directing air outside of the wake field into the wake field to increase speed of airflow in the wake field, and directing the airflow into the second plurality of turbine blades of the second wind turbine.

Systems, methods, and non-transitory computer readable media including instructions for coordinating MPPT operations for a cluster of geographically-associated fluid turbines are disclosed. Coordinating MPPT operations for a cluster of geographically-associated fluid turbines includes receiving data from the cluster of geographically-associated fluid turbines; determining changes to total power output of the cluster based on changes in loading states of individual fluid turbines in the cluster; selecting a combination of loading states for the individual fluid turbines in the cluster to coordinate total power output for the cluster; and transmitting the selected combination of loading states to at least some of the individual fluid turbines in the cluster in order to vary rotational speeds of the at least some of the individual fluid turbines in the cluster.