A method for monitoring of a wind turbine including: a) acquiring respective values of one or more operation variables of the wind turbine at the corresponding operation time point; b) determining the value of a tower clearance resulting from the acquired values of the operation variables with the aid of a trained data driven model, where the value of an output variable which is the tower clearance or a variable correlated with the tower clearance is predicted by feeding the acquired value of each operation variable as a digital input to the trained data driven model which outputs the predicted value of the output variable as a digital output, the tower clearance being shortest the distance between the tower and the tip of a specific rotor blade from the rotor blades when the specific rotor blade is in its lowermost position in which it points downward in the vertical direction.

The invention relates to a method of determining a tip-to-tower clearance of a wind turbine, the wind turbine comprising a wind turbine tower, where a distance sensor unit is arranged on at least one wind turbine blade of the wind turbine and comprises at least a transmitter and a receiver, wherein the method comprises the steps of: transmitting a signal from the distance sensor unit toward the wind turbine tower, measuring a signal reflected from the wind turbine tower, determining a distance between the wind turbine tower and the at least one wind turbine blade based on the transmitted signal and the reflected signal, wherein the method further comprises the step of correcting the measured distance based on at least one of an actual pitch angle and a deflection angle of the at least one wind turbine blade at the location of the distance sensor unit.

A method for controlling pitching of at least one rotor blade of a wind turbine includes receiving, via one or more position localization sensors, position data relating to the at least one rotor blade of the wind turbine. Further, the method includes determining, via a controller, a blade deflection signal of the at least one rotor blade based on the position data. Moreover, the method includes determining, via a computer-implemented model stored in the controller, a pitch command for the at least one rotor blade as a function of the blade deflection signal and an azimuth angle of the at least one rotor blade.

In a wind turbine comprising a tower supporting a nacelle, at least one blade rotationally attached to the nacelle and having a blade-tip section, a system for measuring the separation distance between the tower and the blade-tip-section of the wind turbine, comprising an indicator stripe on the surface of the blade-tip section, an indicator ring encircling the tower, a camera in the nacelle and positioned such that the blade-tip section and the indicator ring are within the camera's field of view when the blade-tip is at its closest approach position to the tower, the camera digitally recording an image of its field of view at this closest approach position, the distance between indicator ring and camera being essentially equal to the distance between the indicator stripe and the camera at this closest approach position, and an image processor and tip-tower clearance calculator unit receiving the digitally recorded image and calculating a physical separation distance between the indicator stripe and the indicator ring using the digitally recorded image information, the physical separation distance being indicative of the blade tip-tower clearance.

The present disclosure relates to methods and systems for measuring deflection of blades of a wind turbine. Examples include a light emitting and collection device mounted to the nacelle and configured to emit light in a direction within a substantially vertical plane. Examples include a method for operating a wind turbine including emitting light above a hub, receiving the light when reflected by a blade of the wind turbine, and, if the level of blade deflection is above a threshold, reducing blade loading of the blade before the blade reaches a vertically downward position. Examples include a method for monitoring deflection of a rotor blade of a wind turbine comprising emitting a light sheet, collecting reflections of the emitted light, and determining deflection of the rotor blade by determining a time during which the blade reflects the emitted light sheet.

An acoustic monitoring system and method for the health status of an offshore wind turbine and an ocean wave are provided. The acoustic monitoring system includes a first laser transmitter, a second laser transmitter, a telephoto camera provided at a hub, a vibration detection sensor provided on a tower of a wind turbine, and four acoustic detection sensors arranged at an interval of 90° along the circumference of the tower. The first and second laser transmitters are arranged at the bottom of a nacelle of the wind turbine and emit laser lights vertically downward. The first laser transmitter, the second laser transmitter, the telephoto camera, the vibration detection sensor, and the acoustic detection sensors are connected to a data acquisition and conversion module through a transmission module. The acoustic monitoring system combines laser light detection with acoustic signal feature detection to improve stability and safety of the offshore wind turbine.

A clearance monitoring system of a wind turbine, and a monitoring method and device are provided. The clearance monitoring system includes a processor and a millimeter wave radar in communication connection to the processor. The millimeter wave radar is installed on a left side portion of a nacelle of the wind turbine. The millimeter wave radar points to a movement area of the impeller and is used for monitoring movement data of each blade on the impeller in the movement area. The processor is used to receive the movement data. According to the movement data, blade clearance between each blade and a tower of the wind turbine is determined.

A rotor blade for addressing the deflection of rotor blades of a wind turbine. The rotor blade includes a plurality of exterior surfaces defining a blade body having a pressure side, a suction side, a leading edge and a trailing edge. The blade body extending between a blade tip and a blade root. The blade body including a breakaway tip portion defined by a predetermined breaking point. The breakaway tip portion is configured to break away from the remaining portion of the blade body when subject to a predetermined tower strike load. A wind turbine including the rotor blade configuration is further disclosed.

An upwind wind turbine comprising a tower and a rotor is described. The wind turbine additionally includes a pressure-sensing device supported by the tower at a location within the wake of the rotor. The pressure-sensing device is configured to sense air pressure and provide a signal indicative of the sensed air pressure to a wind turbine controller for use in controlling the rotor of the wind turbine.

A method for the calculation of a wind turbine blade deflection is described. The method utilises a known blade modal profile in the calculation of the blade deflection, such that the a priori knowledge of the blade excitation modes can be used with a simple distance measurement to determine the blade deflection shape. The calculated blade deflection can then be used as an input to control wind turbine operation, e.g. where it is likely that the deflected blade might result in a tower strike.