Abstract: A method for operating a wind farm having a first wind power installation and a second wind power installation, to an associated wind power installation and to an associated wind farm. The second wind power installation is located in the wake of the first wind power installation in at least one wake wind direction. A tip-speed coefficient is determined from the ratio of a second tip-speed ratio of the second wind power installation and a first tip-speed ratio of the first wind power installation and a pitch-angle coefficient is determined from the ratio of a second pitch angle of the second wind power installation and a first pitch angle of the first wind power installation.

Abstract: A method for providing a requested real power including receiving the requested real power at a transmission feed-in point; using a real power band with an upper band limit and a lower band limit, each of which is disposed with an offset from the requested real power. The real power band furthermore comprises at least one control threshold value between the upper band limit and the lower band limit. The method includes controlling at least one regenerative energy generator depending on the at least one control threshold value, in particular in order to provide the requested real power as transmission power at the transmission feed-in point.

Abstract: A method for controlling a wind power installation having a rotor operated with variable speed and having rotor blades that are adjustable in their blade angle. The installation is controlled in a partial-load range by an open-loop operating-characteristic control, which uses an operating characteristic. The operating characteristic presets a relationship between the rotational speed and a generator state variable to be set that is a generator power or torque. A value of the generator state variable preset by the operating characteristic is set in dependence on a detected speed. The installation is controlled in a full-load range by a closed-loop pitch control, in which the rotational speed is controlled to a speed setpoint value by adjusting the blade angles. In a presettable range of the partial-load range and/or in a transitional range from the partial-load range to the full-load range, the installation is controlled by a speed-power control.

Abstract: Provided is a method for controlling a wind power installation, the wind power installation having a generator for the generation of electric current, the generator having an air gap with a variable air gap thickness, the wind power installation being controlled in a part load range by means of a control regulation, the wind power installation being controlled in a manner which is dependent on the air gap thickness, the control regulation being selected or set in a manner which is dependent on the air gap width.

Abstract: Provided is a method for controlling at least two frequency-converter-based infeeders. The method includes specifying a first droop for a first frequency-converter-based infeeder and specifying a second droop for a second frequency-converter-based infeeder, where the second droop is different from the first droop. The method includes, controlling the first frequency-converter-based infeeder in dependence on the first droop, and controlling the second frequency-converter-based infeeder in dependence on the second droop.

Abstract: Provided is a method for controlling, by means of field-oriented closed-loop control, an active rectifier which is electrically connected to a stator of a generator of a wind turbine. The generator has a rotor which is mounted so as to be rotatable about the stator and comprises the steps of determining a mechanical position of the rotor with respect to the stator, predefining DC components of rotor-fixed d and q coordinates for at least one 3-phase stator current, determining an AC component for the q coordinate at least as a function of the mechanical position of the rotor, modulating the determined AC component of the q coordinate onto the predefined DC component of the q coordinate, so that a modulated q coordinate is produced which has a DC component and an AC component, and controlling the active rectifier at least as a function of the modulated q coordinate and preferably as a function of the d coordinate.

Abstract: A method for operating a wind power installation for the purpose of generating electrical power from wind, wherein the wind power installation has an aerodynamic rotor having rotor blades that can be adjusted in their blade angle, and the rotor is operated at a settable rated rotor speed, wherein a turbulence class at a site of the wind power installation is determined, and the rated rotor speed is defined in dependence on the determined turbulence class.

Abstract: Thus there is provided a method of installing rotor blades of a wind turbine to a rotor hub of the wind turbine. The wind turbine has a tower having a tower longitudinal axis. The rotor hub has a first, a second and a third rotor blade connection. The rotor hub is rotated until the first rotor blade connection is at an angle of 90° or 270° with respect to the tower longitudinal axis. The first rotor blade is lifted substantially horizontally and fixed to the rotor blade connection. The rotor hub is rotated so that the second rotor blade connection is at an angle of 90° or 270° with respect to the tower longitudinal axis. The second rotor blade is lifted substantially horizontally and fixed to the second rotor blade connection. The rotor hub is further rotated until the third rotor blade connection is at an angle of 60° or 300° with respect to the tower longitudinal axis. The third rotor blade is lifted at an angle of ?=30° with respect to a horizontal and fixed to the third rotor blade connection.

Abstract: A method for pretensioning a tower of a wind power installation, comprising the steps: providing a tensioning device having an adapter element and/or a foundation arrangement and a tensioning element, and/or an adapter element and/or a foundation arrangement, fastening a lower end of a tensioning element a fastening means of the adapter element, fastening an upper end of a tensioning element to an upper end of the tower, tensioning the tensioning element at the lower end of the tensioning element and/or at the upper end of the tensioning element, wherein the tensioning of the tensioning element is effected by reduction of a clearance between the foundation and the adapter element.

Abstract: A method of repairing a wind turbine rotor blade, in particular an existing wind turbine rotor blade, that has erosion damage or transport damage. A first region is ablated into a surface or a surface coating of the rotor blade. An adhesive is applied to the ablated region, an erosion protection film is placed on the adhesive and the adhesive is cured.

Abstract: Rotor blade for a wind power installation, rotor for a wind power installation, and wind power installation. The disclosure relates in particular to a rotor blade for a wind power installation, having a rotor blade length, having a profile depth established between a leading edge and a trailing edge, and having a profile thickness established between a suction side and a pressure side, wherein the rotor blade has a trailing edge region, which adjoins the trailing edge and extends with a region extent of less than 20%, in particular less than 10%, of the profile depth in the direction of the leading edge, wherein the trailing edge region has at least one acoustic opening.

Abstract: Provided is a method for controlling a wind power installation and/or a wind farm having at least one wind power installation, particularly in the case of asymmetrical network voltages, comprising: measuring a first voltage of a first phase, a second voltage of a second phase and a third voltage of a third phase of a three-phase electrical system, calculating a symmetrical negative-sequence voltage system from the measured voltages including a first negative-sequence voltage, a second negative-sequence voltage and a third negative-sequence voltage, predefining setpoints for a negative-sequence current system depending on the calculated, symmetrical negative-sequence voltage system including a first negative-sequence current component, a second negative-sequence current component and a third negative-sequence current component, wherein the setpoints are defined such that a balancing of the measured voltages is achieved, feeding an asymmetrical three-phase AC current into a wind farm network or an electrical su

Abstract: A wind-power-installation tower segment, a wind-power-installation tower, a wind power installation, a use of a holding arrangement, a use of a first transport device and of a second transport device, and to methods for assembling a wind-power-installation tower segment and for assembling a wind-power-installation tower section.

Abstract: A method for detecting low-frequency oscillations, in particular subsynchronous resonances, in a grid is provided. The method includes recording a series of measurements, having measurement points, of a grid variable over a measurement time period, for performing a frequency analysis and multiplying the series a time-dependent sinusoidal test function for the same measurement time period. The test function is characterized by a test frequency and a test angle as phase angle. The series for each measurement point is multiplied by the test function in order to obtain a test product for each measurement point. The method includes adding the test products taking into consideration the mathematical sign thereof to give a product sum, and evaluating, depending on the product sum, whether the series of measurements has a low-frequency oscillation having a frequency in the region of the test frequency and a phase angle in the region of the test angle.

Abstract: Provided is a method for controlling a wind power system, that is to say a wind power installation or a wind farm comprising a plurality of installations, for feeding electrical power from wind into an electrical supply grid, and for damping low-frequency oscillations, in particular subsynchronous resonances, in the grid, wherein the grid has a line voltage with a nominal line frequency, wherein a damping control with a closed control circuit is used for damping the low-frequency oscillations, and the damping control for damping the low-frequency oscillations controls a feed-in of electrical power into the grid using a wind system control, the damping control is designed for a controlled system comprising the grid, the wind power system, and the wind system control, or parts thereof, wherein the damping control is designed such that it prevents and/or damps weakly damped modes in the closed control circuit.

Abstract: Provided is a method for damping low frequency oscillations, in particular subsynchronous resonances, in an electrical supply grid by way of at least one decentralized production unit connected to the electrical supply grid, in particular a wind turbine or a wind farm, comprising the steps: feeding electrical power by way of the at least one production unit and supplementing the feeding by way of a supplementary component for damping the low frequency oscillations, wherein the supplementary component is determined depending on a simplified model of a synchronous machine.

Abstract: Provided is a method for feeding electrical power into an electrical supply network using a converter-controlled infeed apparatus. The apparatus feeds into a local network section of the electrical supply network at a network connection point. The network has further infeed apparatuses and consumers for consuming electrical power. The local section has a ratio of power able to be fed in using converters to a total power able to be fed in by all infeed apparatuses of at least 50%. A controller controls the infeed of the electrical power depending on a network state of the network. The controller has control behavior that depends on a network characteristic of the local section. The network characteristic is dependent on at least one property of the local section and at least one property of a further network section of the network or a determination that no further network section is present.

Abstract: There is provided a method of controlling a wind turbine on starting or running up the wind turbine before the wind turbine is connected to an electrical supply grid or before the wind turbine is connected to the electrical energy supply grid again. The wind turbine has a rotor having a rotor arresting means, at least one rotor blade and at least one blade angle detection sensor for each rotor blade for detecting the blade angle of the rotor blade. The blade angle of the at least one rotor blade is detected by means of the blade angle detection sensor. Unlocking of the rotor arresting means is blocked until the detected at least one blade angle is within a predetermined angle range. In that way it is possible to ensure that the rotor arresting means is released only when the blades are for example in the feathered position.

Abstract: The disclosure concerns a wind turbine, comprising: a hub with a hollow cylindrical region with a mean circumference UN; at least one rotor blade mounted rotatably on the hub, with a blade laminate which extends in the longitudinal direction of the rotor blade and at least in portions forms a hollow cylinder with a mean circumference UR; and at least one blade bearing for mounting the rotor blade on the hub, with a first bearing ring which is arranged on the hub side and connected by means of a first flange connection to a rotor hub flange formed on a rotor-blade side end portion of the hub, wherein the first flange connection has at least one hub longitudinal bolt which is arranged on a circumference UNB coaxially to the blade bearing; and a second bearing ring which is arranged on the rotor blade side and connected by means of a second flange connection to a rotor blade flange formed on a hub-side end portion of the rotor blade, wherein the second flange connection has at least one rotor blade longitudinal

Abstract: The present disclosure relates to a method for operating a converter on a three-phase electrical power supply grid, comprising the following steps: operating the converter in a first operating mode by means of a control unit for generating an output current, wherein the converter in the first operating mode operates in such a way as to apply a voltage to the electrical power supply grid; detecting a grid fault on the electrical power supply grid by means of a detection means during the first operating mode; limiting the output current of the converter by means of current limitation when a grid fault on the electrical power supply grid has been detected during the first operating mode, in particular in such a way that the output current of the converter falls below a predetermined maximum current or substantially corresponds thereto.