Abstract: The present invention relates to methods, controllers and computer program products for determining an optimal tilt angle for a wind turbine. One or more signals indicating site conditions at and/or near a wind turbine are received 402 and an optimal tilt angle for said wind turbine based on said received one or more signals indicating site conditions is determined 403. The optimal tilt angle is then transmitted 404 to a platform controller such that said wind turbine can be inclined said optimal tilt angle.

Abstract: The invention relates to a method for wind turbine generators for reducing electrical disturbances in the form of power variations which are caused by damping controllers arranged the compensate structural oscillations by inducing shaft torque variations. The shaft torque variations are generated by imposing corresponding variations in a generator set-point, e.g. a power or torque set-point. Variations in the generator set-point cause undesired variations in the power injected to the grid by one or more wind turbine generators. According to an embodiment of the invention the electrical disturbances may be reduced by limiting a damping controller's control action. The amount of limitation or restriction of the damping controller may be determined on basis on electrical disturbance information determined from power measured e.g. at a location on the grid.

Abstract: The invention relates to a method for determining dynamic parameters associated with damping properties of a wind turbine. The method involves active excitation of tower oscillations by adjusting the pitch or rotor torque. After the active excitation, the parameters can be determined from the passive decay of the excited oscillations. Alternatively, the oscillations can be actively damped, so that the parameters can be determined from the active decay of the excited oscillations. The method for promoting oscillations may be triggered in response to different events or in response to predetermined times for determining the actual dynamic parameters.

Abstract: The present invention refers to a method for operating a wind turbine, the wind turbine particularly comprising a tower and a rotor with rotor blades. The pitch angles of the rotor blades are adjusted to generate a force on the rotor and the tower. The force is adjusted to counteract and damp an oscillation. The adjustment is enabled by an activation decision unit, if the activation decision unit decides that certain parameters characterising the oscillation or loads of the tower indicate a requirement and/or if the activation decision unit determines that the generated force is sufficient to counteract an oscillation of the tower.

Abstract: The invention relates to a control apparatus and method for controlling the rotor blades of a wind turbine, and in particular to controlling the rotor blades during an extreme wind event. An extended mode of operation of the wind turbine rotor beyond the cut-out wind speed is provided. In the extended mode of operation, the pitch of the wind turbine blades is actively controlled so that the rotor and the generator idle at a designated rotational speed. The rotational speed may be relatively high, say 15 to 20% of the nominal speed, compared with minimal speeds experienced by purely feathered wind turbine blades, and may be further controlled as a function of the incident wind speed. Output power control in the extended mode may be zero but is preferably a low, but non-zero value. The output power so produced may then be used as an auxiliary power source for controlling the wind turbine in situations where the utility grid fails.

Abstract: The present invention relates to methods and apparatus for removing or substantially reducing negative damping effects on a floating wind turbine. An operating point signal is received and a gain scheduling parameter is determined based on the received operating point signal. An input signal is then gain scheduled by the gain scheduling parameter and based on at least the gain scheduled input signal the negative damping effects on a floating wind turbine can be removed or substantially reduced.

Abstract: Embodiments of the invention provide methods, systems, and apparatus for determining a property of wind approaching a wind turbine. A light detection and ranging equipment may be used to determine a property of the wind at a plurality of locations ahead of a turbine. A wind flow model may be used to determine the property of wind expected at the rotor of the wind turbine based on the readings of the light detection and ranging device.

Abstract: The invention relates to a controller configured to determine one or more future values of blade control references and/or a generator control references for a wind turbine generator. The first of the future values of the control references are used for control purposes. The future control references are determined from a physical model of a system of the wind turbine generator by solving an optimization problem which includes at least one cost function and at least one constraint.

Abstract: Embodiments of the invention provide methods, systems, and apparatus for determining a property of wind approaching a wind turbine. A light detection and ranging equipment may be used to determine a property of the wind at a plurality of locations ahead of a turbine. A wind flow model may be used to determine the property of wind expected at the rotor of the wind turbine based on the readings of the light detection and ranging device.

Abstract: The present invention relates to methods and apparatus for operating a safety system in a floating wind turbine. The floating wind turbine comprises one or more sensors 202, 203, and receives a fore-aft inclination signal from the sensor 202, wherein the fore-aft inclination signal indicates an inclination of said floating wind turbine in a fore-aft direction. A side-to-side inclination signal is also received from the sensor 203, wherein the side-to-side inclination signal indicates an inclination of said floating wind turbine in a side-to-side direction. An operational parameter of the floating wind turbine is altered based on either or both of said fore-aft inclination signal and said side-to-side inclination signal.

Abstract: The present invention relates to methods, controllers and computer program products for determining an optimal tilt angle for a wind turbine. One or more signals indicating site conditions at and/or near a wind turbine are received 402 and an optimal tilt angle for said wind turbine based on said received one or more signals indicating site conditions is determined 403. The optimal tilt angle is then transmitted 404 to a platform controller such that said wind turbine can be inclined said optimal tilt angle.

Abstract: The present invention relates to methods, apparatus and computer program products for coordinating the control of a floating wind turbine (101) between a wind turbine controller (111) and a platform controller (110). One or more wind turbine control systems and/or one or more platform control systems may be altered based on 102 said coordinated control of said floating wind turbine (101).

Abstract: Wind turbines of a wind power plant may be selectively over-rated by measuring the difference between the nominal and actual power plant outputs and deriving an over-rating request signal based on that difference which is sent to each turbine. The same value may be sent to each turbine. Alternatively, each turbine may be given its own over-rating amount based on an optimization of the turbine. Over-rating may also be used when external economic factors such as energy costs are sufficiently high to out-weigh any potential harmful effect of over-rating. The fatigue lifetime of turbines and their critical components may also be taken into account when deciding whether and to what extent to implement an over-rating command.

Abstract: Wind turbines of a wind power plant may be selectively over-rated by measuring the difference between the nominal and actual power plant outputs and deriving an over-rating request signal based on that difference which is sent to each turbine. The same value may be sent to each turbine. Alternatively, each turbine may be given its own over-rating amount based on an optimisation of the turbine. Over-rating may also be used when external economic factors such as energy costs are sufficiently high to out-weigh any potential harmful effect of over-rating. The fatigue lifetime of turbines and their critical components may also be taken into account when deciding whether and to what extent to implement an over-rating command.

Abstract: Embodiments of the invention provide methods, systems, and apparatus for determining a property of wind approaching a wind turbine. A light detection and ranging equipment may be used to determine a property of the wind at a plurality of locations ahead of a turbine. A wind flow model may be used to determine the property of wind expected at the rotor of the wind turbine based on the readings of the light detection and ranging device.