Abstract: The rotor blades of a wind turbine each have a plurality of fiber-optic pressure variation sensors which can detect the onset of a stall condition. The output of the stall condition sensors is input to a stall count circuit which increases a stall count signal each time a stall indication is received. The stall count signal is decayed exponentially over time and the current signal is summed with the decayed signal from a previous sampling period to form a value from which a stall margin is determined. An ?:? curve of tip speed to wind speed ratio ? against pitch angle reference ? is then determined from the stall margin.

Abstract: The present invention relates to control of the power output of wind turbine generator that operates in derated mode to generate a produced power output level lower than an available power level. A pitch system 48 sets the blade pitch of a rotor to a pitch value based on the received power reference signal 40. A power system 43 controls the produced power output power level of the wind turbine to the requested power output level. Moreover, the blade pitch of the rotor is further controlled by a pitch feedback control loop 47 that modifies the pitch value based on a difference between the produced power output level 46 and the requested power output level 40.

Abstract: The disclosure is provides for warning a wind turbine generator (WTG) in a wind park of an extreme wind event. According to one embodiment, one or more front line WTGs of the wind park that detect extreme wind events and provide the warning are adaptively selected based on a measured wind direction. Thus, the selection of front line WTGs is adaptive to changing wind conditions. In another embodiment, a wind park includes a group of one or more WTGs of a first type located in an inner region of the wind park and a plurality of WTGs of a second type located in an outer region of the wind park that at least partially surrounds the inner region. The first type of WTG is structurally weaker and/or rated for higher performance than the second type of WTG.

Abstract: Embodiments of the present disclosure generally relate to apparatus and methods for preventing power dips associated with power ramping in wind turbines. One embodiment of the present disclosure provides a method for stabilizing power output in a wind turbine, which includes tracking a rate of change in an external reference, such as an external power reference or external torque reference, computing a feed-forward pitch angle adjustment according to the rate of change in the external power reference, and sending the feed-forward pitch angle adjustment to the wind turbine to adjust a pitch angle of rotor blades simultaneously with adjusting power output according to the external reference.

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 method of controlling a wind turbine, the wind turbine comprising wind turbine blades attached to a rotor hub and a control system for pitching the blades relative to the hub. The method comprises providing wake sectors assigned to different wind directions and providing a normal pitch schedule to control an output parameter of the wind turbine (e.g. power, rotational speed), comprising pitch reference values as a function of the wind speed and at least one of the parameters of thrust coefficient C, and axial induction factor a. Further, is provided a modified pitch schedule to control a modified output parameter of the wind turbine, comprising pitch reference values in dependence of the wind speed and at least one modified parameter of the thrust coefficient and/or the axial induction factor.

Abstract: The rotor blades of a wind turbine each have a plurality of fibre-optic pressure variation sensors which can detect the onset of a stall condition. The output of the stall condition sensors is input to a stall count circuit which increases a stall count signal each time a stall indication is received. The stall count signal is decayed exponentially over time and the current signal is summed with the decayed signal from a previous sampling period to form a value from which a stall margin is determined. An ?:? curve of tip speed to wind speed ratio ? against pitch angle reference ? is then determined from the stall margin.

Abstract: A method of estimating an amount of undesired loading experienced by at least a portion of a structure (100) is provided. The structure (100) may be, for example, a wind turbine generator (WTG) and the portion for which undesired loading is estimated may be, for example, a rotor (130) of the WTG. The method includes receiving a first signal characterizing instantaneous stress experienced by a component (140) of the structure (100) and filtering out at least a portion of the received first signal that corresponds to the desired loading experienced by the component to produce a first filtered signal. The amount of undesired loading experienced by the at least a portion of the structure (100) is estimated based at least partially on the first filtered signal.

Abstract: Embodiments of the invention generally relate to wind turbine generators, and more specifically to the deactivation of wind turbines in a wind turbine park. A wind park controller may be configured to retrieve data indicating fatigue experienced by each wind turbine of the wind turbine park, and deactivate those turbines determined to be the most fatigued, thereby increasing the lifetime of turbines in the wind turbine park.

Abstract: A method of controlling a wind turbine comprising blades attached to a rotor hub for rotation in a rotor plane and a control system for individually pitching the blades relative to the hub. The method comprises dividing the rotor plane into a number of sectors, determining the individual sectors for each blade during the rotation by means of an azimuth angle sensor, and obtaining blade sensor data from a blade sensor on an individual blade relating to a sector, and comparing the obtained data with data relating to the same sector and representing blade sensor data on other blades. When an event is detected in a given sector, an individual pitch contribution is determined in the sector, and the blades are then pitched according to this individual pitch contribution for that given sector at least partly during passage of the sector.

Abstract: Embodiments of the invention generally relate to wind turbine generators, and more specifically to improving power production in wind turbine generators. A rotor plane of the wind turbine may be divided into a plurality of sections. A characteristic of wind associated with each section may be determined. An optimal pitch angle may be determined for each section based on the associated wind characteristic. A pitch controller may adjust the pitch angle of a blade to the optimal pitch angle as the blade sweeps through the section.

Abstract: The disclosure is provides for warning a wind turbine generator (WTG) in a wind park of an extreme wind event. According to one embodiment, one or more front line WTGs of the wind park that detect extreme wind events and provide the warning are adaptively selected based on a measured wind direction. Thus, the selection of front line WTGs is adaptive to changing wind conditions. In another embodiment, a wind park includes a group of one or more WTGs of a first type located in an inner region of the wind park and a plurality of WTGs of a second type located in an outer region of the wind park that at least partially surrounds the inner region. The first type of WTG is structurally weaker and/or rated for higher performance than the second type of WTG.

Abstract: An electrical steering system for a vehicle includes an electrically supplied steering motor arrangement which is connected with an inverter arrangement, whose output voltage is influenced by a computer arrangement, and a sensor arrangement. To reduce the cost of the steering system while also allowing the steering system to be steerable during braking in the case of a fault, the steering motor arrangement has a redundant steering motor which is connected with the computer arrangement via two separately run control circuits. The control circuits have separate electric supplies and the computer arrangement is redundant.

Abstract: An electrical steering system for a vehicle includes an electrically supplied steering motor arrangement which is connected with an inverter arrangement, whose output voltage is influenced by a computer arrangement, and a sensor arrangement. To reduce the cost of the steering system while also allowing the steering system to be steerable during braking in the case of a fault, the steering motor arrangement has a redundant steering motor which is connected with the computer arrangement via two separately run control circuits. The control circuits have separate electric supplies and the computer arrangement is redundant.