The invention concerns a method of operating a wind power installation in which the rotor is brought to a halt and fixed, comprising the steps: braking the rotor, positioning the rotor at a stopped position, and fixing the rotor in the stopped position. According to the invention it is provided that an end position is predetermined, the rotor is braked in regulated fashion to a stopped position associated with the end position, and for positioning for the predetermined end position the rotor is braked in an automated procedure until stopped at the stopped position, and for fixing in the stopped position a mechanical fixing device is applied, in particular automatically.

A multi-stage compression system in which gases compressed by a pair of first-stage compressors are compressed by subsequent compressors connected to the first-stage compressors in series includes a valve control unit configured to output open/close signals for opening/closing valves for adjusting flow rates of gases flowing into the first-stage compressors provided at inlet sides of the first-stage compressors. The valve control unit outputs an open/close signal having a difference less than or equal to a predetermined value with respect to a degree of opening of the valve before malfunction determination as the open/close signal until a malfunction is eliminated after the determination of the malfunction in which one of the valves does not have a degree of opening according to the open/close signal.

A method of controlling a wind turbine having a generator system coupled to an electrolyzer for producing H2 from water is provided, the method including: identifying a characteristic of a load situation; operating the electrolyzer at a load and/or H2-output above a respective nominal rated value depending on the characteristic of a load situation; monitoring the state of the electrolyzer; and operating the electrolyzer at a load and/or H2-output not above the nominal value, if at least one state parameter is above a threshold.

Techniques for controlling the yaw of a wind turbine system by controlling a plurality of yaw drive actuators. When the yaw drive actuators are applying the same torque to all the motors, this can lead to some motors overspeeding, if the motor is not engaged when the yaw system is activated. Therefore, if the actual motor speed reference of a yaw drive actuator is higher than a specific motor speed reference, then an output signal to reduce the actual motor speed reference is applied to the yaw drive actuators with an actual motor speed reference higher than the specific motor speed reference.

A wind turbine system comprising: a wind turbine; and a monitoring system, wherein the wind turbine comprises: a tower; an arm extending from the tower, a rotor-nacelle assembly (RNA) carried by the arm; and a Global Navigation Satellite System (GNSS) sensor carried by the arm or the RNA. The monitoring system is configured to receive position data from the GNSS sensor and obtain a moment or force measurement on the basis of the position data.

The present invention relates to a control system for thrust-limiting of wind turbines, which wind turbine comprises at least one tower, which tower carries at least one nacelle which nacelle comprises a rotating shaft, which shaft is rotated by one or more blades, which blades at pitch regulated by a pitch control system. It is the object of the present invention to reduce mechanical load and stress of a wind turbine. A further object is to reduce the maximal load on tower of a wind turbine. The thrust-limiting control system performs control of the pitch angle, which thrust-limiting control system performs regulation of the pitch angle based on at least a first input from a wind estimator and a second input from a turbulence estimator. By thrust-limiting control, reduction in the maximum mechanical load on a tower, or maybe also a nacelle, can be achieved by a relatively high percentage of the load in a way where it has only very limited influence on the power production of the wind turbine.

The invention relates to a device for measuring moments of a wind turbine, comprising a carrier pin that can be fixedly connected to a bedplate of a nacelle of the wind turbine, which is arranged on a tower and can be adjusted with respect to yaw, a torque support of a gearbox of the wind turbine being mountable on the carrier pin via an elastomer body, and to a method for operating a wind turbine and the corresponding wind turbine. The carrier pin is provided with one or more sensors that are designed and arranged to detect strains and/or shears of the carrier pin, a signal processing and/or evaluation unit being provided, which is connected to the sensor(s) and which can determine, during operation of the wind turbine, from measurement signals of the sensors, pitch moments and/or yaw moments that act upon the torque support.

A method for operating a wind turbine for generating a settable turbine power, where the wind turbine includes a rotor having rotor blades adjustable in their blade angle, is operable at a settable rotor speed, and is installed at an installation site at a distance to an obstacle, comprises the obstacle causing a wind disturbance, which, in dependence on current wind direction and wind velocity, can reach the wind turbine as a wind wake, and the wind turbine reducing its turbine operation by throttling down for protection against loads due to the wind wake, wherein the throttling down is controlled in dependence on the current wind direction and the current wind velocity, wherein a weather prediction is used in order to take into consideration at least one further weather property in addition to the wind direction and wind velocity, and wherein the throttling down is additionally controlled in dependence on the weather prediction, in particular on the further weather property.

The present disclosure relates to methods for protecting one or more components of a wind turbine during yawing of the wind turbine. The present disclosure further relates to wind turbines. A method for protecting one or more components of a wind turbine during yawing of the wind turbine comprises monitoring one or more parameters indicative of a yaw torque required to position a wind turbine rotor with respect to a prevailing wind direction, detecting that one or more of the parameters indicative of yaw torque reach or exceed a predetermined threshold, and in response to the detection, reducing load imbalance in the wind turbine rotor.

There is presented a wind turbine system, wherein the wind turbine system is comprising a support structure, a plurality of wind turbine modules mounted to the support structure wherein each of the plurality of wind turbine modules comprises a rotor, and wherein the wind turbine system further comprises a control system, wherein the control is arranged to execute a wind turbine system transition from a first system operational state of the wind turbine system to a second system operational state of the wind turbine system, and wherein the wind turbine system transition is performed by executing a plurality of wind turbine module transitions from a first module operational state of a wind turbine module to a second module operational state of the wind turbine module wherein the plurality of wind turbine module transitions are distributed in time with respect to each other.