Abstract: A method for operating a wind turbine is provided, wherein the wind turbine includes a rotor and plurality of blades configured for rotating about a rotor axis such that a rotor disk is defined by a circular area swept by the blades. The wind turbine includes a nacelle, a tower, and a yaw system configured to yaw the nacelle and the rotor about a longitudinal axis of the tower. The method detects or predicts a fire in a first one of the blades and adjusts an azimuth angle of the rotor about the rotor axis such that the first blade is positioned in an upper half of the rotor disk. The nacelle and rotor are yawed away from an incoming wind direction to a yaw angle of more than 90 degrees and less than 270 degrees.

Abstract: A method for controlling a wind turbine includes receiving, via a control system, at least one speed condition of a drivetrain of the wind turbine from a first sensor. The method also includes receiving, via the control system, a pulse from a second sensor mounted within a nacelle of the wind turbine, the pulse being generated when the drivetrain shifts to a known angle. The method also includes estimating, via the control system, an azimuth of a designated rotor blade based on a combination of the at least one speed condition of the drivetrain and the pulse. The method also includes implementing, via the control system, a control action for the wind turbine based on the estimated azimuth.

Abstract: The present disclosure relates to a method (100) of controlling operation of a wind turbine (10). The method (100) comprises receiving operational (215) data indicative of oscillations in a wind turbine rotor (18). The method (100) comprises deriving a first signal (224) representative of loads in a first direction in a reference plane and a second signal (226) representative of loads in a second direction in the reference plane. The second direction is different from the first direction. The method (100) further comprises determining an amplitude (A1, A2) of the first (224) and second (226) signals, as well as a phase offset (?1-?2) between the first (224) and second (226) signals. Finally, the method (100) comprises controlling the wind turbine (10) based on the amplitudes (A1, A2) and the phase offset (?1-?2). The disclosure also relates to a control unit (36) for controlling operation of a wind turbine (10) and to a wind turbine (10).

Abstract: A method for damping drivetrain vibrations of a wind turbine. The drivetrain has, at least, a rotor and a generator. The method includes receiving a first rotational speed signal at a first location along the drivetrain, the first rotational speed signal being a proxy for rotor speed of the rotor. The method also includes receiving a second rotational speed signal at a second location along the drivetrain, the second location being downwind from the first location, the second rotational speed signal being a proxy for generator speed of the generator. Further, the method includes determining a speed error based on a comparison of the first and second rotational speed signals. Moreover, the method includes determining a torque deviation signal for the wind turbine configured to dampen the drivetrain vibrations when the speed error exceeds a first speed threshold. In addition, the method includes applying the torque deviation signal to the generator to dampen the drivetrain vibrations.

Abstract: A method for controlling a wind turbine includes receiving, via a control system, at least one speed measurement from at least one sensor on a drivetrain of the wind turbine. The method also includes receiving, via the control system, at least one rate gyroscope speed measurement from at least one rate gyroscope on the drivetrain of the wind turbine. The method also includes calculating, via the control system, an offset for the at least one rate gyroscope speed measurement as a function of the at least one speed measurement. The method also includes adjusting, via the control system, the at least one rate gyroscope speed measurement by the offset. The method also includes implementing, via the control system, a control action for the wind turbine based on the adjusted at least one rate gyroscope speed measurement.

Abstract: The present disclosure relates to methods (100, 200, 300) for controlling a wind turbine (10) during a yaw operation. The present disclosure further relates to control systems (92) for wind turbines and to wind turbines (10). A method for operating a wind turbine (10) during yaw operation comprises operating one or more yaw drives (35) to rotate the nacelle (16) with respect to the tower (15). In addition, the method comprises predicting an end of the yaw operation and, in response to predicting an end of the yaw operation, actuating a hydraulic brake (94) before the predicted end.

Abstract: A method for controlling a wind farm having a plurality of wind turbines electrically connected to an electrical grid through a point of interconnection includes (a) determining, via a controller of the wind farm, a phase and an amplitude of individual power oscillations from each of the plurality of wind turbine power systems. The method also includes (b) determining, via the controller, a farm-level power oscillation for the wind farm based on the individual power oscillations from each of the plurality of wind turbine power systems. Further, the method includes (c) implementing, via the controller, a phase-shifting control scheme using the phases and the amplitudes of the individual power oscillations from each of the plurality of wind turbine power systems so as to maintain the farm-level power oscillation below a predetermined oscillation threshold.

Abstract: A method for detecting and responding to a failure in a drivetrain of a wind turbine includes estimating a first rotational speed signal at a first location along the drivetrain via one or more rate gyroscopes mounted in a hub, the first rotational speed signal being a proxy for rotor speed of a rotor. The method also includes processing the first rotational speed signal to account for a bias in the first rotational speed signal due to use of the rate gyroscope(s). Further, the method includes receiving a second rotational speed signal at a second location along the drivetrain, the second location being downwind from the first location, the first and second locations being on opposing sides of a potential slip location of the drivetrain. Moreover, the method includes determining a speed error based on a comparison of the first and second rotational speed signals.

Abstract: The present disclosure relates to methods (100, 200, 300) for controlling a wind turbine (10) during a yaw operation. The present disclosure further relates to control systems (92) for wind turbines and to wind turbines (10). A method for operating a wind turbine (10) during yaw operation comprises operating one or more yaw drives (35) to rotate the nacelle (16) with respect to the tower (15). In addition, the method comprises predicting an end of the yaw operation and, in response to predicting an end of the yaw operation, actuating a hydraulic brake (94) before the predicted end.

Abstract: A method for reducing loads acting on a wind turbine includes determining, via a processor, at least one loading condition of the wind turbine resulting from a wind shear condition below a design threshold, determining, via the processor, a rotor speed setpoint of the wind turbine to cause an increase in thrust when the at least one loading condition exceeds a loading threshold; operating the wind turbine based on the rotor speed, and operating a rotor imbalance control module of the wind turbine to at least partially compensate for the at least one loading condition of the wind turbine resulting from the wind shear condition below the design threshold.

Abstract: A method for reducing loads acting on a wind turbine includes determining, via a processor, at least one loading condition of the wind turbine resulting from a wind shear condition below a design threshold, determining, via the processor, a rotor speed setpoint of the wind turbine to cause an increase in thrust when the at least one loading condition exceeds a loading threshold; operating the wind turbine based on the rotor speed, and operating a rotor imbalance control module of the wind turbine to at least partially compensate for the at least one loading condition of the wind turbine resulting from the wind shear condition below the design threshold.

Abstract: A method for controlling a wind farm having a plurality of wind turbines electrically connected to an electrical grid through a point of interconnection includes (a) determining, via a controller of the wind farm, a phase and an amplitude of individual power oscillations from each of the plurality of wind turbine power systems. The method also includes (b) determining, via the controller, a farm-level power oscillation for the wind farm based on the individual power oscillations from each of the plurality of wind turbine power systems. Further, the method includes (c) implementing, via the controller, a phase-shifting control scheme using the phases and the amplitudes of the individual power oscillations from each of the plurality of wind turbine power systems so as to maintain the farm-level power oscillation below a predetermined oscillation threshold.

Abstract: A system for measuring displacements of a blade root of a rotor blade of a wind turbine includes a hub, and a rotor blade coupled to the hub by a pitch bearing. The system further comprises a reference plane and at least one displacement sensor. The reference plane is configured to move with the rotor blade as the rotor blade moves relative to the hub while the displacement sensor is fixed to the hub and the displacement sensor is configured to detect a displacement of the reference plane relative to the hub without physical contact. Alternatively, the reference plane has a fixed position with respect to the hub while the displacement sensor is fixed to the rotor blade and the displacement sensor is configured to detect a displacement of the reference plane relative to the rotor blade without physical contact.

Abstract: A method (100) of mounting blades (22) to a rotor hub (20) of a wind turbine (10), the wind turbine (10) comprising a tower (12), a nacelle (16) mounted on the tower (12), the rotor hub (20) being coupled to the nacelle (16), and blades (22), each blade (22) comprising a blade root segment (56) and a blade extension segment (66), the method (100) comprising mounting a first blade root segment (50) to the rotor hub (20), mounting a second blade (72) to the rotor hub (20) after mounting the first blade root segment (50), the second blade (72) comprising a second blade root segment (52) and a second blade extension segment (62), and connecting a first blade extension segment (60) to the first blade root segment (50) after mounting the second blade (72).

Abstract: A method (100) of mounting blades (22) to a rotor hub (20) of a wind turbine (10), the wind turbine (10) comprising a tower (12), a nacelle (16) mounted on the tower (12), the rotor hub (20) being coupled to the nacelle (16), and blades (22), each blade (22) comprising a blade root segment (56) and a blade extension segment (66), the method (100) comprising mounting a first blade root segment (50) to the rotor hub (20), mounting a second blade (72) to the rotor hub (20) after mounting the first blade root segment (50), the second blade (72) comprising a second blade root segment (52) and a second blade extension segment (62), and connecting a first blade extension segment (60) to the first blade root segment (50) after mounting the second blade (72).

Abstract: A wind turbine and associated control method includes a controller configured with a high speed shaft brake in the generator gear train. The controller receives an input signal corresponding to rotational speed of the high speed shaft, wherein upon the high speed shaft reaching a predefined rotational speed and under a braking condition that calls for the rotor to come to a complete standstill, the controller generates an activate signal to activate the brake. An interlock system is in communication with the low speed shaft sensor and the controller and is configured to override the activate signal when the rotational speed of the low speed shaft is above a threshold value.

Abstract: A system for measuring displacements of a blade root of a rotor blade of a wind turbine is disclosed. The system comprises a hub, a rotor blade coupled to the hub by a pitch bearing. The system further comprises a reference plane and at least one displacement sensor. The reference plane is configured to move with the rotor blade as the rotor blade moves relative to the hub while the displacement sensor is fixed to the hub and the displacement sensor is configured to detect a displacement of the reference plane relative to the hub without physical contact. Alternatively, the reference plane has a fixed position with respect to the hub while the displacement sensor is fixed to the rotor blade and the displacement sensor is configured to detect a displacement of the reference plane relative to the rotor blade without physical contact.

Abstract: A method for testing capacity of at least one energy storage device of a pitch drive mechanism to drive a first rotor blade of a wind turbine connected to a power grid includes defining a rotor position range for implementing a first test procedure for the energy storage device(s). Further, the method includes monitoring a rotor position of the first rotor blade. When the rotor position of the first rotor blade enters the rotor position range, the method includes initiating the first test procedure. The first test procedure includes pitching the first rotor blade via the energy storage device(s), measuring at least one operating condition of the energy storage device(s) during pitching, and determining a capacity of the energy storage device(s) to drive the first rotor blade based on the operating condition(s) thereof.

Abstract: Methods and a computer-readable storage device for detecting shared audio content between first audio content information and second audio content information is provided. The methods cluster similar fingerprints to lessen the impact that similar or repetitive sounds have on the final decision, thereby producing a more accurate final decision about whether the first audio content information shares audio content with the second audio content information.

Abstract: Methods and a computer-readable storage device are disclosed for generating a frequency representation of a query audio file. The frequency representation represents information about at least a number of frequencies within a time range containing a number of time frames of the audio content information and a level associated with each of said frequencies. At least one of area of data points in the frequency representation is selected. A fingerprint for each selected area of data points is generated by applying a trained neural network onto said selected area of data points thereby generating a vector in a metric space. A distance between at least one of the generated query fingerprints and at least one reference fingerprint is calculated using a specified distance metric. A reference audio file having associated reference fingerprints which have produced at least one associated distance satisfying a predetermined threshold is identified.