Abstract: The present invention relates to control of a wind turbine to reduce structural loading due to vibrations of the blades along the edgewise direction. A rotor control system for actuating pitch of pitch-adjustable rotor blades of a wind turbine is disclosed. Pitch modification signals are determined based on edgewise load signals for each of the rotor blades. The edgewise load signal are coordinated transformed and input into a primary whirling controller unit to provide whirling signal components which can be used for determining the pitch modification signals.

Abstract: The invention relates to a method for controlling a power generating unit. The method includes determining a virtual impedance value, determining a virtual grid power based on the virtual resistance value and the grid current, determining a virtual synchronous machine rotational speed and/or a synchronous machine angle of a virtual synchronous generator, and determining a voltage reference for controlling a line side converter to generate the desired reactive power based on the virtual synchronous machine rotational speed or angle, a virtual voltage and the voltage magnitude reference.

Abstract: A pitch system for rotating a blade of a wind turbine relative to a hub. The pitch system comprises a blade bearing including an inner bearing ring and an outer bearing ring, wherein the outer bearing ring is rotatable relative to the inner bearing ring, and an actuator system configured to control relative rotational movement between the inner bearing ring and outer bearing ring, comprising. The actuator system comprises a first load transfer beam arrangement spanning at least first and second fixing positions associated with the inner bearing ring, a second load transfer beam arrangement spanning at least first and second fixing positions associated with the outer bearing ring, and a first linear actuator coupled between the first load transfer beam arrangement and the second load transfer beam arrangement. A benefit of the pitch system of the invention is that it achieves a reduction in mass yet retains a stiff connection between the hub and an associated blade.

Abstract: According to the present invention there is provided a wind turbine blade extending in a spanwise direction between a root and a tip, and in a chordwise direction between a leading edge and a trailing edge. The wind turbine blade has a spar cap comprising a plurality of strips of fibrous composite material. Each strip extends in the spanwise direction between a first end and a second end to define a length of the strip, and each strip has a width and a thickness, the width being less than the length, and the thickness being less than the width. Each strip has upper and lower major surfaces defined by the length and width dimensions. Each strip has side surfaces defined by the length and thickness dimensions. The plurality of strips includes a first strip and a second strip. The first strip has a tapered end portion in which the thickness of the first strip decreases towards the first end of the first strip.

Abstract: A wind turbine blade having a blade shell with a lightning protection system. The lightning protection system has a first metal layer at an outer surface of the blade shell and a second metal layer at the outer surface of the blade shell and stacked on the first metal layer to form intimate electrical contact with the first metal layer at a multiple-thickness region.

Abstract: Techniques for authenticating and authorizing user access to a component of a power plant within a private network of a renewable power plant having wind turbine generators. One technique includes providing at a local computer system in the private network a list of credentials and authorizations representing a plurality of identifiers and authenticators of users and corresponding access authorizations. The local computer is in direct communication with components of the power plant and is configured to receive a request for access from a user via a computer interface in the component in the private network. If the requested access can be granted by consulting the list of credentials and authorizations, the grant is communicated from the local computer to the computer interface in the component, and in case access cannot be granted, a request for update of the list of credentials and authorizations is communicated from the local computer system to a central computer system outside the private network.

Abstract: The invention relates to a method for controlling a power plant during an event which requires a change of the power produced by the power plant, wherein the power plant comprises a plurality of power generating units including at least one wind turbine generator, the method comprises determining the power reference dependent on an available power, changing the power reference to a modified power reference by a power variation in response to detecting a first event, memorizing a power level relating to the actual power production at a time occurrence of the first event, setting a maximum power limit to the memorized power level, limiting the modified power reference to the maximum power limit, and controlling the power produced by the wind turbines in accordance with the limited modified power reference.

Abstract: The invention relates to a method for providing power ramp rate control of a hybrid power plant with a plurality of energy assets including wind turbine generators and possibly solar power units, and an energy storage unit. Each energy asset has a ramp rate capability defined as the highest possible ramp rate at a given time, and the method includes receiving from each energy asset the corresponding ramp rate capability, and taking into account the ramp rate capabilities from the energy assets when calculating the power setpoint to each energy asset, so as to improve the power ramp rate control of the hybrid power plant.

Abstract: Embodiments herein describe optimizations for hybrid power plants that include wind turbine generators and photovoltaic generators by determining solar tracking setpoints for a field of photovoltaic generators co-located with a wind turbine generator, wherein the solar tracking setpoints orient a collector face for each photovoltaic generator sunward; in response to determining based on data received from the wind turbine generator that an airborne impactor event is occurring, adjusting the solar tracking setpoints to reposition the collector face out of a trajectory for airborne impactors; and transmitting the setpoints to tracking motors for the photovoltaic generators of the field.

Abstract: A method of charging an energy storage system, such as a battery, a capacitor, or a super capacitor, using a wind turbine is described. The method comprises establishing if turbine power production can be increased and establishing if the energy storage system is capable of taking a charge. If both conditions are met, the power generated by the wind turbine is increased above a rated power of the wind turbine and the additional power is used to charge the energy storage systems. A method of control is also disclosed.

Abstract: The invention provides a method of controlling operation of a wind turbine having a tower. The method includes determining an overall control output including lateral oscillation control for dampening lateral oscillation of the tower, and using the overall control output to control wind turbine operation. The method further includes receiving lateral oscillation sensor data indicative of a level of lateral oscillation of the tower, determining a rated lateral oscillation control output in dependence on the received lateral oscillation data, and receiving an indication of yaw error of the wind turbine. A lateral oscillation control output included in the overall control output is determined to be de-rated from the rated lateral oscillation control output when the indicated yaw error is above a predetermined lower threshold level.

Abstract: The present invention relates to a rotor control system for actuating pitch of pitch adjustable rotor blades of a wind turbine in order to reduce edgewise blade vibrations. The system comprises a pitch actuation unit being arranged to receive an edgewise load signal and apply m-blade coordinate transformations, such as the Coleman transformations, to the edgewise load signal. Based on a selected signal component at either a backward whirling frequency or a forward whirling frequency, a modified modification signal is obtained.

Abstract: A method of providing safety configuration parameters for a wind turbine is provided. The method comprises receiving a safety configuration file at a location of the wind turbine, and comparing a turbine ID associated with the safety configuration file to a turbine ID of the wind turbine stored at the location of the wind turbine. A tamper check is performed on the safety configuration file to determine if data in the safety configuration file has been modified. If the turbine ID associated with the safety configuration file matches the turbine ID of the wind turbine, and if the tamper check determines that the data has not been modified, a safety configuration parameter associated with a safety system of the wind turbine is extracted from the file and stored.

Abstract: In a first aspect of the invention there is provided a method of manufacturing a wind turbine blade. The method comprises providing a mould for a shell of the wind turbine blade, the mould extending in a longitudinal direction from a root end to a tip end; providing a plurality of elongated root inserts; providing a root plate with a plurality of arcuately arranged connection points; at the connection points, connecting the root inserts to the root plate, such that the connected root inserts jointly form a contour of a portion of a root section of the wind turbine blade; and positioning the root plate relative to the mould in order to place the contour formed by the root inserts at least partially into the mould. The method further comprises providing a spacer having a decreasing thickness, and the connecting of the root inserts to the root plate comprises providing the spacer between the root inserts and the root plate.

Abstract: A wind turbine blade comprising a lightning protection system, which is at least partly disposed in an inboard portion of the blade. The lightning protection system comprises a plurality of inboard down conductor cables and a diverging electrical junction. The lightning protection system may comprise a down conductor cable having root and tip portions having insulation with different electrical breakdown voltages and/or a down conductor cable portion and a supporting component to hold the cable portion in free space in a position near or on a camber line of the blade aerofoil section, so that the cable portion is spaced apart from at least one electrically conductive structural component.

Abstract: Aspects of the present invention relate to a method for controlling a renewable power plant connected to a power network to reduce deviation of a measured frequency of the power network from a target frequency. The method comprises determining a forecasted power gradient over a forecast interval defined between a first time point and a second time point, and, at a third time point during the forecast interval, controlling the power plant to output active power according to a minimum active power level if the measured frequency at the third time point is below the target frequency, controlling the power plant to output active power according to a maximum active power level if the measured frequency at the third time point is above the target frequency. The maximum and minimum active power levels are based on the forecasted power gradient.

Abstract: The invention provides a method for handling a blade (11) for a horizontal axis wind turbine (1), the blade extending longitudinally between a blade root (111) and a blade tip (112), the method comprising—supporting the blade (11) with one or more cranes (3), moving, by means of the one or more cranes (3), the supported blade (11) so as to be placed on one or more first support elements (4111) of a first support device (411) and on one or more second support elements (4121) of a second support device (412), removing the support of the one or more cranes (3), so as for the blade (11) to be supported by the one or more first support elements (4111) and the one or more second support elements (4121) on which the blade is placed, the second support device (412) being located between the blade root (111) and the blade tip (112), and the first support device (411) being, compared to the second support device, located closer to the blade root, moving the first and second support devices (411, 412) so as to move the

Abstract: Aspects of the present invention relate to a method for controlling one or more wind turbine generators. The method comprises: receiving a trigger signal, and implementing an active power boost mode during a predetermined time period in response to receiving the trigger signal. The active power boost mode comprises: disregarding further trigger signals; and generating one or more upper active power limits for each of the one or more wind turbine generators, wherein, during at least a first portion of the predetermined time period, the one or more upper active power limits are fixed at an active power boost level that is greater than a nominal active power level of the one or more wind turbine generators.

Abstract: A method of preparing a wind turbine blade, comprising: removing at least a portion of a layer of material covering a region of a metallic part of the wind turbine blade from the wind turbine blade, applying a metal salt to the metallic part, the metal salt being arranged to oxidise a metal of the metallic part, such that the metal salt and the metal of the metallic part react and a new compound is formed on the metallic part.

Abstract: Operating a renewable energy generator forming part of a renewable energy power plant. During a fault experienced by a power network: determining an active current set point to enable a reactive current supply boost at the point of connection between the plant and the network, the active current set point being based on a voltage level associated with the generator and on operational characteristics of the generator, plant, power network and/or connecting network; calculating a time period for the reactive current boost, the time period being the maximum time that the active current set point can be maintained for; and controlling the generator during the calculated time period to alter active current output to the determined active current set point, thereby providing the reactive current supply boost at the point of connection.