Provided is a method for controlling an electric generator of a wind turbine. The method includes varying an amplitude and/or phase angle of an harmonic current of said electric generator, while said electric generator is rotating, in particular at a known condition, measuring a signal indicative of generator vibration after and/or during varying said amplitude and/or phase angle, repeating said varying and said measuring until a predetermined requirement is met, evaluating an operating point for said electric generator by using said measured signals indicative of generator vibration in order to reduce a ripple torque of said generator, and controlling a current, in particular said harmonic current, of said electric generator in order to meet said operating point.

A method for operating a generator of a wind turbine includes generating, via a controller, a time series of a plurality of operating signals of the generator. The method also includes applying at least one algorithm to the time series of the plurality of operating signals of the generator to generate a processed time series of the of the plurality of operating signals of the generator. Moreover, the method includes identifying, via the controller, patterns in the processed time series of the plurality of operating signals of the generator to identify one or more of at least one slip event occurring in the slip coupling or a surface health of the slip coupling. Further, the method includes implementing, via the controller, a control action when the at least one slip event occurring in the slip coupling is identified or the surface health of the slip coupling is indicative of degradation in the slip coupling.

The invention relates to a method for operating a wind turbine which comprises a power generator, a generator side converter, a grid side converter, a DC link electrically connected to an output of the generator side converter and an input of the grid side converter. The method comprises monitoring a wind turbine signal for detection of an operational condition which requires an increase of an output voltage of the grid side converter, upon detection of the operational condition, initiate an over-modulation mode wherein the grid side converter is operated with a modulation index in an over-modulation range, and upon the detection of the operational condition, initiate a DC-voltage adjustment mode wherein the a DC-voltage of the DC link is increased from a first voltage level towards a second voltage level.

A system and method are provided for controlling a wind turbine to protect the wind turbine from anomalous operations. Accordingly, in response to receiving data indicative of an anomalous operational event of the wind turbine, the controller initiates an enhanced braking mode for the wind turbine. The enhanced braking mode is characterized by operating the generator at a torque setpoint that generates maximum available torque for a given set of operating conditions. Additionally, the torque setpoint is in excess of a nominal torque limit for the generator.

The present disclosure relates to methods (300) to determine a duration of a period for warming up of a power converter (20) of a wind turbine (1). The method (300) comprises determining (301) a first indicator that is indicative of a time that the power converter (20) has been inactive. Further, the method (300) comprises determining (302) the period for warming up at least partially based on the first indicator. A power converter assembly is also disclosed.

A flywheel is attached to a shaft of a turbine. As the shaft rotates, the flywheel swings outwards away from the shaft and regulates the angular velocity of the rotating shaft. In an embodiment, there are multiple flywheels attached to the shaft. In another embodiment there is a first flywheel that controls a second flywheel. In another embodiment, the flywheel has adjustable or centrifugal displacement of counterbalanced masses for effective rotational diameter with effective rotational balance. In another embodiment, a small pilot centrifugal displacement flywheel may control a clutch by rotational velocity and may include a hysteresis control. An example of a clutch may limit that degree to which the arms of the flywheel may be extended and/or retracted. In another embodiment, a small pilot centrifugal displacement flywheel controls the hysteresis of a centrifugal flywheel displacement.

A method for providing grid-forming control of an inverter-based resource includes monitoring the electrical grid for one or more grid events. The method also includes controlling, via a power regulator of a controller, an active power of the inverter-based resource based on whether the one or more grid events is indicative of a severe grid event. In particular, when the one or more grid events are below a severe grid event threshold, thereby indicating the one or more grid events is not a severe grid event, the method includes controlling, via the power regulator, the active power according to a normal operating mode. Further, when the one or more grid events exceed the severe grid event threshold, thereby indicating the one or more grid events is a severe grid event, the method includes controlling, via the power regulator, the active power according to a modified operating mode. Moreover, the modified operating mode includes temporarily re-configuring the power regulator to reduce or eliminate power overloads induced by the severe grid event for as long as the one or more grid events exceed the severe grid event threshold.

Provided is a method of controlling a wind turbine during damping a mechanical oscillation of the wind turbine having a generator system coupled to a rotor at which plural rotor blades are mounted, the method including: generating a damping control signal in dependence of an indication of the oscillation; performing damping control of the generator system based on the damping control signal causing damping related power output variation at an output terminal of the generator system; and controlling an energy storage device connected to the output terminal of the generator system and connected to an output terminal of the wind turbine based on the damping control signal.

The present disclosure relates to a wind turbine comprising a wind turbine rotor with a plurality of blades supported on a support structure, a generator operatively coupled to the wind turbine rotor for generating electrical power, a power electronic converter for converting electrical power generated by the generator to a converted AC power of predetermined frequency and voltage, and a main wind turbine transformer having a low voltage side and a high voltage side for transforming the converted AC power to a higher voltage. One or more electric filters are connected to the high voltage side of the main transformer, wherein the electric filters are arranged in the support structure. The present disclosure also relates to wind farms, and particularly offshore wind farms, and to methods for operating wind farms.

A method of operating a wind turbine wherein the wind turbine includes a doubly-fed induction generator that converts rotational mechanical power to electrical power. The method includes operating the wind turbine in a first operational mode in which a speed of a rotor of the wind turbine is controlled to maximize the power generation by the wind turbine. Upon a monitored parameter reaching or dropping below a respective threshold, the wind turbine is operated in a second operational mode. The monitored parameter may include at least one of the rotational speed of the rotor, the rotational speed of the doubly-fed induction generator, a wind speed, an active electrical power, or generator torque. Operating the wind turbine in the second operational mode may include increasing the rotational speed of the doubly-fed induction generator at the expense of the generation of active electrical power by the power generating system.