The present invention relates to a damper unit for damping oscillations of a tower structure when secured thereto, the damper unit comprising a damper unit structure adapted for attachment to the tower structure, a pendulum structure, a suspension arrangement for suspending the pendulum structure from the damper unit structure such that the pendulum structure is allowed to displace from a neutral position for the pendulum structure, the suspension arrangement comprising one or more wires for suspending the pendulum structure, a sensor adapted for measuring oscillations of the tower structure, and tuning means configured for adjusting the natural frequency of the suspended pendulum structure in response to measured oscillations of the tower structure. The present invention further relates to an associated method.

The present invention relates to a damper unit for damping oscillations of a tower structure when secured thereto, the damper unit comprising a damper unit structure adapted for attachment to the tower structure, a pendulum structure, a suspension arrangement for suspending the pendulum structure from the damper unit structure such that the pendulum structure is allowed to displace from a neutral position for the pendulum structure, the suspension arrangement comprising one or more wires for suspending the pendulum structure, a sensor adapted for measuring oscillations of the tower structure, and tuning means configured for adjusting the natural frequency of the suspended pendulum structure in response to measured oscillations of the tower structure. The present invention further relates to an associated method.

A wind power generation device includes a blade, a main shaft of which one end is connected to the blade, a speed increaser connected to the other end of the main shaft, an output shaft of which one end is connected to the speed increaser, a power generation unit connected to the other end of the output shaft, a vibration sensor, and an abnormality diagnosis unit. The power generation unit is configured to rotate the output shaft and the main shaft by performing powering operation. The abnormality diagnosis unit diagnoses the presence or absence of an abnormality based on data acquired by the vibration sensor during a period in which the power generation unit performs powering operation.

A wind power generation device includes a blade, a main shaft of which one end is connected to the blade, a speed increaser connected to the other end of the main shaft, an output shaft of which one end is connected to the speed increaser, a power generation unit connected to the other end of the output shaft, a vibration sensor, and an abnormality diagnosis unit. The power generation unit is configured to rotate the output shaft and the main shaft by performing powering operation. The abnormality diagnosis unit diagnoses the presence or absence of an abnormality based on data acquired by the vibration sensor during a period in which the power generation unit performs powering operation.

A wind turbine is disclosed which comprises a control system configured to execute at least one ice removal routine which comprises a heating stage of at least one of the blades (3), and a mechanical removal ice stage. A wind turbine removing ice method is also disclosed which comprises a stage wherein the presence of ice is detected on at least one of the blades and, once said presence of ice is detected, comprises a stage wherein at least one ice removal routine is activated which comprises, in turn, a heating stage of at least one of the blades and a mechanical removing ice stage on at least said blade.

A wind turbine is disclosed which comprises a control system configured to execute at least one ice removal routine which comprises a heating stage of at least one of the blades (3), and a mechanical removal ice stage. A wind turbine removing ice method is also disclosed which comprises a stage wherein the presence of ice is detected on at least one of the blades and, once said presence of ice is detected, comprises a stage wherein at least one ice removal routine is activated which comprises, in turn, a heating stage of at least one of the blades and a mechanical removing ice stage on at least said blade.

The invention relates to a method for monitoring yawing fault events of a yaw system of a wind turbine. The yaw system comprises one or more actuators for driving the yaw system and a holding system to resist yaw rotation. The yaw system is arranged to provide yaw rotation in response to a yaw control signal. According to the method, the monitored yaw angle is compared with the yaw control signal, and based on the comparison, a correlation between a monitored change in the yaw angle and the yaw control signal is determined. A yawing fault event is determined dependent on the determined correlation.

The invention relates to a method for monitoring yawing fault events of a yaw system of a wind turbine. The yaw system comprises one or more actuators for driving the yaw system and a holding system to resist yaw rotation. The yaw system is arranged to provide yaw rotation in response to a yaw control signal. According to the method, the monitored yaw angle is compared with the yaw control signal, and based on the comparison, a correlation between a monitored change in the yaw angle and the yaw control signal is determined. A yawing fault event is determined dependent on the determined correlation.

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.

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.