Abstract: A wind turbine and a method for locating an event corresponding to a failure of a heating element at a wind turbine blade, the heating element comprising an electric resistive material configured to generate heat using electrical power, the method comprising: —providing a location of an event corresponding to a failure of a heating element, wherein the heating element is in an Ohmic contact with a reference potential; —applying a voltage impulse to the heating element relative to the reference potential at a first point in time; —measuring a voltage at the reference potential at a second point in time; —determine the location based at least on the first point in time and the second point in time.

Abstract: The present disclosure relates to methods (100, 200) for controlling and operating wind turbines (10). More particularly, the present disclosure relates to methods and systems for determining a surface condition of one or more wind turbine blades (22) of a wind turbine (10). a method comprises rotating the wind turbine rotor (18) under the influence of a wind in predetermined rotation conditions, wherein the predetermined rotation conditions include at least a predetermined pitch angle (252) of the additional wind turbine blades (222, 223). The method further comprises determining a current value of one or more parameters of the wind turbine (10) when rotating in the predetermined rotation conditions and comparing the current value of the one or more parameters of the wind turbine with one or more reference values (37) to determine the surface condition of the wind turbine blades (22).

Abstract: A method for controlling wind farm operation during a weak grid condition includes determining when a threshold number of the plurality of wind turbines have tripped based on the received one or more inputs. Furthermore, the method includes determining a sampled power output of the wind farm based on received sensor data after it is determined that the threshold number of the plurality of wind turbines have tripped. Additionally, the method includes controlling the operation of the one or more wind turbines of the plurality of wind turbines that have not tripped after it is determined that the threshold number of the plurality of wind turbines have tripped such that the power output of the one or more wind turbines of the plurality of wind turbines that have not tripped is less than or equal to the sampled power output.

Abstract: The present invention discloses a helicopter hoisting platform for a wind turbine nacelle cover, the helicopter hoisting platform comprising a composite layer and a plurality of metal plates arranged on the outer surface of the composite layer, wherein the plurality of metal plates forms a conductive network electrically connected to a ground connection.

Abstract: The present disclosure relates to wind turbine nacelles (16), comprising a housing including a front side (270), and a rear side (250) separated from the front side along an axial direction (x), first and second sidewalls (260) extending from the front side to the rear side and a roof. The roof comprises one or more roof panels (210, 220, 230, 240), and at least one of the roof panels is a displaceable roof panel configured to be displaced relative along the axial direction (x) to another part of the roof to provide access to the nacelle (16) from above. The present disclosure further relates to methods for providing access to an inside of the nacelle.

Abstract: The present disclosure relates to electrical machines, cooling systems and methods for cooling active elements of electrical machines. More in particular, the present disclosure relates to cooling systems and methods for cooling active rotor and/or stator elements of a generator of a wind turbine, e.g. of a direct drive wind turbine. A cooling method comprises supplying a cooling fluid to an air gap through one or more primary inlets of an electrical machine for cooling a plurality of active elements of a rotor of the electrical machine and/or a plurality of active elements of a stator of the electrical machine separated by the air gap. The method further comprises reversing a direction of flow of the cooling fluid such that the cooling fluid is extracted from the electrical machine through one or more primary inlets.

Abstract: The present disclosure is related to a device 100 configured for aligning a first hole 131 of a first flange 130 with a second hole 141 of a second flange 140. The device 100 comprises a base 101, a shaft 110 extending from the base 101 and a first and a second pusher 115, 116. The shaft 110 is configured to move between a retracted position and an extended position. The shaft 110 in the extended position extends from the first hole 131 into the second hole 141. The first and second pushers 115, 116 are also configured to be moved radially outwardly from the shaft 110 to exert pressure against an inner wall of the first and second holes 131, 141. Methods for aligning a first and a second hole 130, 140 are also provided.

Abstract: A proactive method and related wind turbine system are provided for reducing vibrations in the rotor blades when the rotor hub is locked against rotation. The method includes determining an initial blade orientation to wind direction and wind parameters for wind impacting the rotor blades. Based on the wind parameters and blade orientation, an angle of attack is determined for the rotor blades that will at least reduce vibrations expected to be induced in the blades from the current wind conditions. With a controller, the rotor blades are pitched to achieve the angle of attack using a pitch control system. The angle of attack is determined and the rotor blades are pitched from the initial blade orientation to the new angle of attack prior to vibrations being induced in the rotor blades.

Abstract: A method for detecting a failure condition in one or more components of a wind turbine is provided. The method includes actuating, via a controller, an impact device to generate a vibration having a vibration frequency and a vibration magnitude in the one or more components. The method further includes receiving data indicative of the vibration frequency and the vibration magnitude from a sensor communicatively coupled to the controller. The method further includes determining, via the controller, whether the data indicative of the vibration frequency and/or the vibration magnitude is outside of a predetermined vibration range for the one or more components.

Abstract: The present disclosure relates to an assembly comprising a rotor hub, a generator rotor, and a shaft for supporting the generator rotor on a stationary frame, wherein the rotor hub is configured to be removable from the generator rotor and the shaft without disassembling the generator rotor from the shaft. The present disclosure further relates to methods for assembly.

Abstract: A method for controlling a wind turbine, and an associated wind turbine, includes receiving a wind direction signal indicative of an instantaneous wind direction at the wind turbine and receiving a signal indicative of an instantaneous wind speed at the wind turbine. A rate of change of the wind direction at the wind turbine and a rate of change of wind speed at the wind turbine are determined. A control signal for a pitch system for blades of the wind turbine is determined based on the rate of change of the wind direction and the rate of change of wind speed. The pitch of the blades is then changed with the pitch system based on the control signal to reduce loads on the wind turbine from changes in the wind direction simultaneous with changes in the wind speed.

Abstract: An electrical generator and method for operating the same are provided. Accordingly, the generator includes a non-rotatable component supporting a field winding assembly and a rotatable component oriented to rotate relative thereto. The generator also includes an armature winding assembly fixedly coupled to the rotatable component so as to rotate therewith during operation of the generator. The generator also includes a resistive assembly fixedly coupled to the rotatable component so as to rotate therewith during the operation of the generator. The resistive assembly electrically couples at least two separate phase windings of the armature winding assembly. The resistive assembly is also configured to introduce a resistance into the armature winding assembly in response to an electrical fault.

Abstract: A method for controlling an inverter-based resource having a power converter connected to an electrical grid includes receiving, via a regulator of a controller of the inverter-based resource, a plurality of power signals. The method also includes determining, via the regulator, a power error signal as a function of the plurality of power signals. Further, the method includes receiving, via the regulator, a dynamic multiplier factor from a supervisory controller. Moreover, the method includes applying, via the regulator, the dynamic multiplier factor to one or more gains of the regulator to determine one or more modified gains. In addition, the method includes applying the one or more modified gains to the power error signal to obtain an intermediate power signal. Thus, the method includes generating, via the regulator, one or more control commands for the power converter as a function of the intermediate power signal.

Abstract: A vibration mitigating device for engagement with a wind turbine blade includes an air flow modifying element that is configurable between a retracted configuration and an extended configuration. A frame is attachable to and has a fixed length in a span-wise direction of the wind turbine blade. The air flow modifying element is movable along the frame between the retracted configuration and the extended configuration. In the retracted configuration, the modifying element extends between the blade tip and the blade root with a first spanwise length, and in the extended configuration the modifying element extends between the blade tip and the blade root with a second, greater spanwise length.

Abstract: A method for rotating a hub of a wind turbine in an inching operation to rotate the hub includes reconfiguring the generator from normal operation by coupling a first string of a first electrical phase of the stator in series with a second string of a second electrical phase of the stator, the first and second strings comprising one or more coils coupled in series. Current is provided from a power converter to the first and second strings o rotate the hub. The generator includes a first and a second winding system, each including a plurality of electrical phases in the normal operation. The first string of the first electrical phase is part of the first winding system in normal operation, and the second string of the second electrical phase is part of the second winding system in the normal operation.

Abstract: The present disclosure relates to wind turbine blades (22) configured to receive a peripheral device (250a, 250b, 250c) at a portion of the outer surface (211) of the blade (22), and wherein the wind turbine blade (22) is configured to magnetically couple to the peripheral device (250a, 250b, 250c). The present disclosure also relates to wind turbine blade assemblies (200) and methods (700) to provide the same.

Abstract: The present disclosure relates to methods and tools for mounting and/or removing active parts of a stator of an electrical machine, e.g. a generator. The present disclosure also relates to rotors, stators and generators. A method comprises removing one or more active rotor parts of a rotor of an electrical machine when the rotor is in a removal starting position, arranging a replacement tool in a gap left by the removed active rotor parts, rotating the rotor to an alignment position such that the replacement tool is radially aligned with an active stator part to be removed, picking the active stator part to be removed with the replacement tool, rotating the rotor to an extraction position, and removing the active stator part from the rotor.

Abstract: The present disclosure relates to pitch assemblies and methods for determining one or more pitch references for a pitch control system of a wind turbine. The assembly comprises a wind turbine hub; a pitch bearing including a hub bearing ring configured to be attached to a hub flange and a blade bearing ring configured to be attached to a wind turbine blade; a target configured to be attached to one of the blade bearing ring and the hub; and a sensor configured to be connected to the other of the wind turbine hub and the blade bearing ring, and configured to sense the target such that a position of the target with respect to the sensor can be determined.

Abstract: The present disclosure relates to methods for determining a maximum power setpoint for a wind turbine comprising determining a temperature of one or more wind turbine components, and determining one or more component temperature errors by determining a difference between the temperatures of the wind turbine components and a corresponding threshold temperature for the components. The methods further comprise determining a present power output of the wind turbine and determining the maximum power setpoint at least partially based at least on the component temperature errors, and on a present power output of the wind turbine. The present disclosure further relates to methods for determining a setpoint reduction and to wind turbine control systems and wind turbines configured for such methods.

Abstract: A method for magnetizing a section of one or more permanent magnets arranged substantially in a V-shape, comprising: applying a first magnetic field such that magnetic flux lines are substantially perpendicular to a first leg of the V-shape, and removing the first magnetic field. Then the method comprises applying a second magnetic field such that magnetic flux lines are substantially perpendicular to a second leg of the V-shape, and removing the second magnetic field. Systems and methods for magnetizing sections of permanent magnet modules are also provided.