A method for operating a wind turbine is described. The wind turbine includes a tower having a tower axis, and a nacelle being rotatable about the tower axis. The method includes providing a data set of one or more operational parameters of the wind turbine. The one or more operational parameters depend on the angular position of the nacelle with respect to the tower axis. The method further includes determining an angular position of the nacelle with respect to the tower axis; selecting one or more operational parameters from the data set of one or more operational parameters of the wind turbine depending on the determined angular position of the nacelle; and applying the one or more selected operational parameters to the wind turbine. Further, another method of operating a wind turbine and a wind turbine are described.

A method for determining control parameters of a turbine by consideration of component-relevant temperature limits is provided. The method considers the impact of individual turbine manufacturing tolerances on the turbine performance in a turbine model to determine control parameters for the turbine without damaging it. The method includes the steps of: receiving, by an interface, one or more measurement values of turbine sensors; determining, by a processing unit, at components or turbine places being equipped or not with turbine sensors, one or more virtual parameters and/or temperatures by a simulation of the operation of the turbine, the simulation being made with a given turbine model in which the one or more measurement values and one or more characteristic values of the wind turbine are used as input parameters; and deriving, by the processing unit, the control parameters for the wind turbine from the one or more virtual parameters and/or temperatures.

A method for controlling a wind turbine to decrease blade deflection during tower passage is disclosed. A blade flap moment of the wind turbine blades is measured. A blade flap moment of the wind turbine blades and a rotor tilt moment in a situation where the pitch offset has not been added are estimated, based on the measured blade flap moment. In the case that the estimated blade flap moment exceeds a first activation threshold value and the estimated rotor tilt moment exceeds a second activation threshold value, individual pitch angle adjustment of the wind turbine blades is initiated by adding a pitch offset, at azimuth angles within an azimuth adjustment region corresponding to tower passage of the wind turbine blades.

A method of determining a distance between a rotor blade tip and a tower of a wind turbine includes: estimating the distance based on a strain measurement; measuring the distance; correcting an estimation procedure based on the estimated distance and the measured distance; and deriving a corrected distance based on the corrected estimation procedure.

In a first aspect of the present invention there is provided a wind turbine comprising a tower, a nacelle mounted on the tower, and a rotor mounted to the nacelle. The rotor comprises a hub and at least three wind turbine blades. Each blade extends between a root and a tip. Each blade further comprises a connection point located between the root and the tip. The wind turbine further comprises a plurality of blade connecting members, each blade connecting member being connected between corresponding connection points of a pair of wind turbine blades. The wind turbine further comprises a tensioning system for adjusting the tension in each blade connecting member. The tensioning system comprises a plurality of linear actuators, each linear actuator being coupled between the hub and a respective blade connecting member. Each linear actuator is configured to adjust the tension in the blade connecting member.