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.

The system and method of the present disclosure is configured to monitor changes associated with an air gap by: (1) receiving one or more sensor signals from one or more sensors that are indicative of changes associated with the air gap; and (2) comparing the changes associated with the air gap to certain thresholds to determine if the air gap is in need of attention. The system includes at least one proximity sensor arranged adjacent to the air gap, to monitor the air gap, and a controller. The controller is configured to receive the sensor signal(s) indicative of the changes associated with the air gap. The controller also is configured to compare the changes associated with the air gap to one or more air gap thresholds, and to implement a control action based on this comparison.

The invention relates to a method for identifying an asymmetrical extreme load which is caused by a gust of wind and acts on a wind power installation, wherein the wind power installation has a rotor having at least three rotor blades; the rotor blades are adjustable in terms of the blade angle thereof; and the rotor by way of the rotor blades thereof sweeps a rotor field; and the method comprises continuous detecting of a blade load for each rotor blade; ascertaining for at least one sector of the rotor field at least one temporal sector load profile from blade loads detected of different rotor blades with the same azimuth position, said sector load profile describing a temporal profile of a load on the rotor blades in the sector and containing a profile extrapolated for a future temporal period, wherein the blade loads are detected or taken into account at successive detection time points which are spaced apart by a partial period in which the rotor rotates further by one rotor blade, so that successive blade loads are detected or taken into account for the respective sector; and checking in terms of expecting an extreme load as a function of the at least one sector load profile.

The disclosure relates to a method for operating a wind turbine wherein the method includes: operating the wind turbine over an operating period in accordance with a control strategy, providing one or more input values representing a load acting on at least one component of the wind turbine and providing uncertainties of the input values, determining, based on the input values, an aggregated load value representing an aggregated load acting on the at least one component of the wind turbine over an aggregation period, determining, based on the uncertainties of the input values, an uncertainty of the aggregated load value, determining a statistical load aggregate from the aggregated load value and the uncertainty of the aggregated load value, adjusting the control strategy based on the statistical load aggregate. The disclosure further relates to a wind turbine and a wind farm configured to perform the above method.

An acoustic damper includes a low porosity layer section and a housing. The low porosity layer section is formed in a liner of a gas turbine combustor and has an arrangement of elongated generally S-shaped slots formed therein. The housing has a plurality of feed apertures. The housing is coupled to the low porosity layer section thereby defining a cavity such that air outside the housing is configured to flow through the apertures and through the elongated generally S-shaped slots in the low porosity layer section, thereby transforming acoustic energy into thermal energy and aiding in providing an acoustic dampening effect for the gas turbine combustor during operation thereof.

A method for reducing extreme loads acting on a component of a wind turbine includes measuring, via one or more sensors, a plurality of operating parameters of the wind turbine. Further, the method includes predicting at least one blade moment of at least one rotor blade of the wind turbine based on the plurality of operating parameters. The method also includes predicting a load and an associated load angle of the at least one rotor blade as a function of the at least one blade moment. Moreover, the method includes predicting a pitch angle of the at least one rotor blade of the wind turbine. In addition, the method includes generating a load envelope for the component that comprises at least one load value for the pitch angle and the load angle. Thus, the method includes implementing a control action when the load is outside of the load envelope.

A method for operating a wind turbine for generating electrical power from wind, wherein the wind turbine has an aerodynamic rotor with a rotor hub and rotor blades of which the blade angle is adjustable, and the aerodynamic rotor can be operated with a variable rotation speed, and the wind turbine has a generator, which is coupled to the aerodynamic rotor, for the purpose of generating a generator power, wherein the generator can be operated with a variable generator torque, comprising the steps of: determining a loading variable which indicates a loading on the wind turbine by the wind, and reducing the rotation speed and/or the generator power in a loading mode depending on the loading variable, wherein at least one force variable that acts on the wind turbine is used for determining the loading variable or as the loading variable.

The present disclosure relates to a method for operating a wind power installation, in particular for identifying unusual oscillation events, and an associated wind power installation and a wind farm. The method comprises the steps of: providing a parametrized limit for a value of an observed oscillation of a component of the wind power installation; determining a current limit from the parametrized limit taking account of at least one current ambient parameter, in particular an ambient parameter that is indicative for the current incident flow; determining a current value of the observed oscillation of the component; comparing the current value of the observed oscillation of the component with the current limit; and operating the wind power installation on the basis of the result of the comparison.

A method for mitigating loads acting on a rotor blade of a wind turbine includes receiving a plurality of loading signals and determining at least one load acting on the rotor blade based on the loading signals. Further, the method includes determining a type of the load(s) acting on the rotor blade. Moreover, the method includes comparing the load(s) to a loading threshold, such as an extreme loading threshold. In addition, the method includes implementing a control scheme when the load(s) exceeds the loading threshold. More specifically, the control scheme includes providing a first pitching mode for reducing a first type of load, providing a different, second pitching mode for reducing a different, second type of load, and coordinating the first and second pitching modes based on the type of the at least one load to mitigate the loads acting on the rotor blade.

A method is provided for controlling the operation of a wind turbine, the wind turbine including a generator, a converter, a converter control unit, a wind turbine controller and a connection device to an external electrical power grid, wherein electrical power generated by the generator is input into the power grid via the converter, wherein the wind turbine controller is configured to determine a fault condition according to a fault condition signal and to active a safe operating mode in response to the fault condition signal indicating a fault condition, wherein the fault condition signal is determined by evaluating changes in an available output power signal generated by the converter control unit, the available output power signal describing the active output power available from the converter.