A wind turbine generator fault detection method is described. The method includes obtaining a first signal from a generator of a wind turbine and a second signal from a vibration sensor coupled to the wind turbine, the first signal representing an output current of the generator, and the second signal being a time-sampled signal representing vibrations of a bearing in the wind turbine. Determining a shaft rotation frequency signal from the first signal, the shaft rotation frequency signal representing a time-varying rotational speed of a shaft of the wind turbine. Resampling an envelope of the second signal based on the shaft rotation frequency signal to provide a third signal, the third signal being an angular sampled signal. Detecting, by the at least one processor, a fault in the bearing of the wind turbine by identifying a characteristic signature of a bearing fault in the third signal.

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.

A method (2000) for operating a wind turbine (100) including a rotor (106) having rotor blades (108) and a power conversion system (118, 210, 234) mechanically connected with the rotor (106), configured to convert input motive power into electrical output power, and electrically connected to a network (242) for feeding the electrical output power (P) to the network is provided. The method includes initializing (2000), at a first time (t.sub.0), the wind turbine to operate in an overproduction operating mode in which the electrical output power (P(t)) of the power conversion system is increased from an initial electrical output power of the power conversion system by providing kinetic energy stored in the rotor. At a second time (t.sub.2), decreasing (2200) the electrical output power, and integrating a reference power (P.sub.ref, P.sub.0) to determine an energy recovery value (E.sub.rec) are started. An energy response value (E.sub.resp) corresponding to a product of the reference power (P.sub.ref) with a time difference (T.sub.resp) between the second time and the first time is determined (2300). The wind turbine is operated (2400) in a recovery operating mode from a third time (t.sub.3) at which the electrical output power (P) reaches or crosses the reference power (P.sub.ref, P.sub.0) until the energy recovery value becomes at least equal to the energy response value or until the electrical output power reaches or crosses the reference power again from below. In the recovery operating mode, the electrical output power is, limited upwards depending on the reference power and a currently available maximum electrical power output without reducing a speed of the rotor.

A method for controlling a multiphase separately excited synchronous generator in a wind turbine is provided. The generator has a stator and an armature having an excitation input, connected to an excitation controller, for inputting an excitation current or an excitation voltage. The stator has a stator output, connected to a rectifier, for delivering stator currents. The rectifier is controllable to control the stator currents by detecting a speed of the armature or rotor, determining a setpoint power to be delivered by the generator or the turbine based on the speed, determining an excitation current or voltage based on the detected speed and determined setpoint power, inputting the excitation current or voltage by excitation controller at the excitation input, determining the stator currents as setpoint stator currents based on the speed and the setpoint power, and controlling the rectifier to set the stator currents to the setpoint stator currents.

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 system and method for measuring a speed of an engine are provided. The engine has a positive displacement pump drivingly connected to a rotor shaft thereof, the pump having an inlet for receiving a fluid supply and an outlet for outputting pressurized fluid. A sensor signal is received from a pressure sensing device provided at an inlet of the pump, the sensor signal comprising a series of periodic oscillations. A frequency of the oscillations is determined, the frequency proportional to a rotational speed of the rotor shaft. The speed of the engine is then determined from the frequency of the oscillations and the speed of the engine as determined is output for controlling operation of the engine.

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.

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.

Provided is a method for adapting an operating characteristic of a wind power installation. The installation has a rotor with rotor blades having adjustable blade angles and operable with a variable rotor rotational speed. To control the installation, use is made of an operating characteristic which describes a relationship between the rotor rotational speed and an operating variable. The operating characteristic has a first portion with a first rotational speed range and a second portion with a second rotational speed range. The first rotational speed range has lower rotational speeds than the second rotational speed range, and the operating characteristic is adapted such that values of the operating variable of the first portion are increased values of the variable of the second portion are changed toward higher rotational speeds, and an expected total number of revolutions of the rotor over a predetermined lifetime of the installation remains approximately the same.

A method for operating a wind turbine, an associated wind turbine, and an associated wind park are provided. The wind turbine has a tower with tower loads acting thereon and an aerodynamic rotor which generates a rotor thrust. The method has a step of reducing the rotor thrust. The reduction of the rotor thrust is performed while considering the effect of the reduction of the rotor thrust on the tower loads. Thus, the reduction of the rotor thrust is avoided in cases which result in undesirable or even counter-productive effects on the tower loads.