Abstract: Techniques for controlling the yaw of a wind turbine system by controlling a plurality of yaw drive actuators. Based on a requested motor speed reference as an input signal, and a mean motor speed reference as a feedback signal, the method determines a required motor torque reference as an output signal for the plurality of yaw drive actuators. The plurality of yaw drive actuators rotates a nacelle or a structure comprising a plurality of nacelles such that an even load distribution is provided for the plurality of yaw drive actuators.

Abstract: The invention relates to a method for controlling a wind turbine system, more particular for a controlled sliding strategy to lower loads on the yaw system by controlling mechanical brakes and motor brakes in the yaw drive actuators. When the yaw system being in the non-yawing operational state, and the mechanical brake(s) being in an engaged state, and the yaw controller determines or receives a signal indicative of a yaw moment, and if the signal indicative of a yaw moment is above a signal threshold, then the yaw controller sends a braking signal to the yaw drive actuators to enter the motors into the brake state to apply a braking torque.

Abstract: A method of yawing a nacelle in a wind turbine having a yawing assembly comprising a drive-ring and a plurality of drives configured to exert a torque during movement along the drive-ring and thereby move the nacelle relative to the tower. The drive-ring is made of drive-ring segments joined in intersections. The method comprises defining a location for each intersection, defining a reference torque exerted by the drives when moving along the drive-ring, defining a reduced torque being lower than the reference torque, determining when a crossing drive moves across the location of an intersection, and to increase the lifetime, exerting the reduced torque by the crossing drive.

Abstract: 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.

Abstract: A method of yawing a nacelle in a wind turbine having a yawing assembly comprising a drive-ring and a plurality of drives configured to exert a torque during movement along the drive-ring and thereby move the nacelle relative to the tower. The drive-ring is made of drive-ring segments joined in intersections. The method comprises defining a location for each intersection, defining a reference torque exerted by the drives when moving along the drive-ring, defining a reduced torque being lower than the reference torque, determining when a crossing drive moves across the location of an intersection, and to increase the lifetime, exerting the reduced torque by the crossing drive.

Abstract: The invention relates to a method for controlling a wind turbine system, more particular for a controlled sliding strategy to lower loads on the yaw system by controlling mechanical brakes and motor brakes in the yaw drive actuators. When the yaw system being in the non-yawing operational state, and the mechanical brake(s) being in an engaged state, and the yaw controller determines or receives a signal indicative of a yaw moment, and if the signal indicative of a yaw moment is above a signal threshold, then the yaw controller sends a braking signal to the yaw drive actuators to enter the motors into the brake state to apply a braking torque.

Abstract: 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.

Abstract: Techniques for controlling the yaw of a wind turbine system by controlling a plurality of yaw drive actuators. Based on a requested motor speed reference as an input signal, and a mean motor speed reference as a feedback signal, the method determines a required motor torque reference as an output signal for the plurality of yaw drive actuators. The plurality of yaw drive actuators rotates a nacelle or a structure comprising a plurality of nacelles such that an even load distribution is provided for the plurality of yaw drive actuators.

Abstract: Method of lifting a wind turbine part (58) at a wind turbine site (1, 2), the method includes: providing a lifting apparatus (60) and a wind turbine part (58) to be lifted; providing a shield (40); providing manipulation equipment (45) associated with said shield (40); and suspending said part (58) from said lifting apparatus (60); moving said part (58) by means of said lifting apparatus (68); the method further including holding said shield (40) proximate and upwind of said part (58) being lifted by means of said manipulation equipment (45). The shield (40) may be held proximate the part (58) being lifted such that it acts to reduce the ambient wind force incident on the part (58). Preferably the method may be implemented such that wind speed conditions (w) at the part (58) being lifted are lower than ambient wind conditions (W) at said site (1, 2).

Abstract: Method of lifting a wind turbine part (58) at a wind turbine site (1, 2), the method includes: providing a lifting apparatus (60) and a wind turbine part (58) to be lifted; providing a shield (40); providing manipulation equipment (45) associated with said shield (40); and suspending said part (58) from said lifting apparatus (60); moving said part (58) by means of said lifting apparatus (68); the method further including holding said shield (40) proximate and upwind of said part (58) being lifted by means of said manipulation equipment (45). The shield (40) may be held proximate the part (58) being lifted such that it acts to reduce the ambient wind force incident on the part (58). Preferably the method may be implemented such that wind speed conditions (w) at the part (58) being lifted are lower than ambient wind conditions (W) at said site (1, 2).