Abstract: Apparatus, systems, and methods for a propeller blade retention system. The retention system may include a hub including a socket formed by an inner surface of the hub, a blade extending into the socket and a retention sleeve having a first portion and a second portion. The retention system may include a filler sleeve disposed between the blade and the second portion of the retention sleeve, a first bearing disposed between the second portion of the retention sleeve and the inner surface of the hub, the first bearing having a first race, and a second bearing disposed between the first portion of the retention sleeve and the inner surface of the hub, the second bearing having a second race. The retention system may include a cap comprising a body portion and a flange portion. The retention system may include a shim carrier.

Abstract: The present invention relates to a free propeller assembly structure and an aircraft structure has the free propeller assembly. The free propeller assembly structure has at least one free propeller assembly. Each of the at least one free propeller assembly has a circular shaft, a main rotor, a signal transmitting device, and a rotor blade assembly. The main rotor has a shaft hole and multiple blade mounting structures radially disposed. Each blade mounting structure is provided with a positioning recess for mounting a driving motor in each positioning recess. The signal transmitting device includes multiple signal transmitters that are able to transmit interpretable electronic signals or photonic signals. The rotor blade assembly includes at least two rotor blades. One end of each rotor blade is connected with an open end of the positioning recesses of a corresponding one of the blade mounting structures.

Abstract: A controller for controlling the operation of a power plant, the power plant comprising a wind turbine and a solar power generator, the controller comprising: an input arranged to receive an input signal indicative of an operating parameter of the solar power generator; a shadow detection module arranged to monitor the operating parameter and to detect a shadow at least partially shading the solar power generator, the detected shadow being caused by a blade of the wind turbine; a shadow prediction module arranged to predict at least one subsequent blade shadow in dependence on the detected blade shadow; a command module arranged to determine a command signal for controlling the solar power generator based on the blade shadow prediction; and an output arranged to output the command signal to the solar power generator.

Abstract: A system for controlling the pitch of a propeller blade for an aircraft turbine engine, including a cup having an annular wall extending about an axis intended to be a pitch setting axis of the blade, and a bottom wall configured so as to cooperate in a form-fitting manner with a free end of the root so that the cup is prevented from rotating relative to the root about the axis, and a locking ring that is configured so as to be mounted within the cup and to cooperate respectively with the root and the annular wall of the cup in order to ensure axial retention of the root in the cup.

Abstract: A turbomachine includes a rotor and a stator, the stator having a plurality of profiled structures, each profiled structure being elongated in a direction of elongation in which the profiled structure has a length exposed to an airflow, and having a leading edge and/or a trailing edge, at least one of which is profiled and has, in said direction of elongation, serrations defined by a succession of peaks and troughs and having a geometric pattern transformed, over at least a part of said length exposed to the airflow, by successive scaling, via multiplicative factors, in the direction of elongation and/or transverse to the direction of elongation. The geometric pattern, as defined with reference to a radial distribution of the integral scale of the turbulence, evolves in a non-periodic manner.

Abstract: The invention relates to a profiled structure elongated in a direction in which the structure has a length exposed to an airflow and transversely to which the structure has a leading edge and/or a trailing edge, at least one of which is profiled and has, along said direction of elongation, geometric serration patterns defined by a succession of peaks and troughs. Along the profiled leading edge and/or trailing edge, the serration patterns have a geometric pattern that is repeated in the direction of elongation, the shape of which is stretched and/or contracted transversely to the direction of elongation and/or in the direction of elongation.

Abstract: A turbomachine comprising a ducted fan, a low-pressure turbine shaft and a reduction gearbox housed in a casing between the fan and the low-pressure turbine shaft, the fan rotor supplying airflow to a primary stream and a secondary stream and comprising a hub of diameter D1, wherein—the diameter D3 of the fan rotor is greater than 82 inches (2.08 metres), —the pressure ratio of the fan is between 1.10 and 1.35, the turbomachine comprises a low-pressure compressor separate from the fan, the reduction gearbox being interposed between the fan rotor and a turbine shaft of the low-pressure compressor, and wherein the reduction gearbox casing has an outside diameter D2 greater than the diameter D1 of the hub, the pitch diameter D4 of the reduction gearbox ring being between 0.15 and 0.35 times the fan rotor diameter.

Abstract: A vortex generator defines a longitudinal direction and has two fins, which are each arranged at an angle in relation to the longitudinal direction and extend over a first length in the longitudinal direction, and a base, which connects the two fins to each other, the base having a width and extending over a second length in the longitudinal direction, wherein the second length is less than the first length over the entire width of the base.

Abstract: A system for feathering a propeller assembly disposed within a housing of the propeller assembly has a sleeve defining an outer wall and one or more sleeve tabs extended outward in a radial direction along at least a circumferential portion of the sleeve, wherein the one or more sleeve tabs is separated from the outer wall in an axial direction, a retainer defining one or more retainer tabs extended inward in the radial direction, wherein the one or more retainer tabs is disposed between the outer wall and the one or more sleeve tabs of the sleeve along the axial direction, and a beta tube assembly extended through the sleeve along the axial direction. The beta tube assembly defines one or more internal walls. The one or more internal walls defines a hydraulic fluid transfer cavity in fluid communication with one or more hydraulic fluid transfer orifices.

Abstract: A wind turbine blade has a vortex generator including a plurality of fins, and a height H(m) of each of the fins and a maximum chord length C (m) of the wind turbine blade satisfies 0.3×10?2?H/C?0.9×10?2. The height H of the fins may satisfy H?0.1?1, provided that ?1 is a boundary layer thickness at a rated tip speed ratio in a blade degradation state. A method for determining arrangement of a vortex generator on the wind turbine blade includes a pair of the fins arranged line-symmetrically with respect to a segment along a chordwise direction of the wind turbine blade.

Abstract: A wind turbine includes a hub rotatable about an axis and a blade coupled to the hub. The blade includes an inner blade portion having a first end and a second end. The inner blade portion is coupled to the hub at the first end and extends radially outward from the hub to the second end. The blade further includes an outer blade portion having a first end and a second end. The first end of the outer blade portion is pivotably coupled to the second end of the inner blade portion.

Abstract: Systems and methods relate to a vertical takeoff and landing (VTOL) platform that can include a stator and a rotor magnetically levitated by the stator. The rotor and stator can be annular, such that the rotor rotates about a rotational axis. The stator can include magnets that provide guidance, levitation, and drive forces to drive the rotor, as well as to control operation of rotor blades of the rotor that can be independently rotated to specific pitch angles to control at least one of lift, pitch, roll, or yaw of the VTOL platform. Various controllers can be used to enable independent and redundant control of components of the VTOL platform.

Abstract: Systems, apparatuses, and methods for overcoming the disadvantages of current air transportation systems that might be used for regional travel by providing a more cost effective and convenient regional air transport system. In some embodiments, the inventive air transport system, operational methods, and associated aircraft include a highly efficient plug-in series hybrid-electric powertrain (specifically optimized for aircraft operating in regional ranges), a forward compatible, range-optimized aircraft design, enabling an earlier impact of electric-based air travel services as the overall transportation system and associated technologies are developed, and platforms for the semi-automated optimization and control of the powertrain, and for the semi-automated optimization of determining the flight path for a regional distance hybrid-electric aircraft flight.

Abstract: This invention employs a generic axial modulating mechanism to manipulate the pitch of the blades of a fan or propeller; conceptually, this is a threaded bolt and nut where the threaded bolt would be analogous to a rotating shaft, with an acme thread (i.e. the “rotor thread”) on its exterior, and the nut would be analogous to the axial modulator of this teaching. The “nut,” or axial modulator, is further spun above and beyond the rotation in the rotating bolt or rotating shaft. The axial motion of the axial modulator is then deployed to do useful work i.e. manipulate the pitch of the blades of a fan or propeller. This invention is a continuation in part of a previous variant disclosed where the means of modulating the axial modulator was magnetic. The variation introduced in this teaching instead achieves the modulation using a gear-driven arrangement.

Abstract: A bladed disc comprising a disc hub; a set of blades angularly distributed around the disc hub; wherein there is variation in a geometric parameter between the blades. The blades are positioned around the disc hub such that for a majority of pairs of neighbouring blades in the set, an interval between values of the geometric parameter between the blades of the pair is less than 0.5 standard deviations of the geometric parameter for the set of blades.

Abstract: A bearing assembly and method of installation. A ball bearing includes an outer race, an inner race, and a separate L-shaped sleeve. In one embodiment, the sleeve is comprised of an axially extending body and a radially extending flange. The axially extending body is configured to be located between an inner diameter of the inner race and a transmission shaft, and the radially extending flange is configured to be located between an inner side surface of the inner race and the transmission shaft. The L-shaped sleeve with splines makes it feasible to sequentially press fit both the inner race and the outer race of the ball bearing. The spline in the axially extending body of the sleeve can slip-fit with the transmission shaft, allowing for ease of assembly, and enabling a press-fit connection between the ball bearing outer race and housing.

Abstract: An elastic flapping hinge for connecting a rotor blade to a rotor hub of a rotary wing aircraft, comprising an elastic flapping hinge member arrangement that includes a hub attachment area for attachment to the rotor hub, a connection area for attachment to the rotor blade, and an elastic flapping hinge area that is arranged between the hub attachment area and the connection area and adapted to allow flapping movements, the elastic flapping hinge member arrangement comprising at least two elastic flapping hinge members having a first bending stiffness for flapping movements and a second bending stiffness for lead-lag movements, the first bending stiffness being smaller than the second bending stiffness, wherein the at least two elastic flapping hinge members diverge from each other in the elastic flapping hinge area by a predetermined divergence angle.

Abstract: A grounding circuit for a backup power source used to power a pitch motor of a pitch system in a wind turbine is provided. The grounding circuit includes one or more switching elements configured to selectively couple the backup power source to a charging circuit based on a state of a first interface element. The grounding circuit further includes one or more switching elements configured to selectively couple the backup power source to ground based on a state of a second interface element. The grounding circuit includes at least one circuit protection device coupled between the backup power source and the charging circuit. When the backup power source is coupled to the charging circuit and subsequently coupled to ground, the at least one circuit protection device is configured to decouple the backup power source from the charging circuit.

Abstract: A system for changing the pitch of blades of at least one turbomachine rotor is provided. The system generally includes a control means acting on a connecting mechanism connected to the blades of the rotor and having a body mobile in translation along a longitudinal axis with respect to a fixed body, load-transfer bearing mounted on the mobile body cooperating with the connecting mechanism, and means for lubricating the bearing having a lubricant duct and extending radially above the fixed and mobile bodies. The duct generally includes first and second telescopic tubular parts that slide coaxially with respect to one another, the first part connected to the fixed body and the second part connected to the mobile body, and means for spraying lubricant into the bearing mounted on the mobile body and lubricant supply conduit mounted on the mobile body to connect the duct to the spraying means.

Abstract: A propeller blade retention element comprises a body portion formed of a corrosion resistant metal, and at least one bearing race portion attached to the body portion, the race portion being formed of an induction hardenable, corrosion resistant metal.

Abstract: A pivot for an adjustable-pitch blade for a turbine engine fan hub, the pivot including a stud having coupling device for transmitting a twisting torque and an outside thread, a force-decoupling part positioned around the stud, provided with an outside thread, pressing transversely against the stud at its radially outer end, an outer rolling bearing having an inside ring mounted to press transversely against the force-decoupling part, an inner rolling bearing assembled around the force-decoupling part and held thereby, a pitch transmission ring provided with a coupling device co-operating, with the coupling device of the stud, a first clamping nut screwed onto the outside thread of the force-decoupling part in order to clamp the outer and inner rolling bearings around the fan hub, and a second clamping nut screwed onto the outside thread of the stud in order to provide clamping between the stud, the force-decoupling part, and the pitch transmission ring.

Abstract: A turbine engine is provided with a longitudinal rotation axis having at least one shaft with a radial axis, in particular a pitch change system for the blades of a propeller, said shaft traversing a radial passage of a substantially cylindrical case around the longitudinal axis. The turbine engine includes an annular oil guiding device around the radial shaft. The device has first and second annular parts nested in one another and secured to one another by hooping. The first part is secured by hooping to the radial shaft, and the second part is configured so as to be separated from the first part under the action of a force oriented along the radial axis and exerted on the second part by a member of the turbine engine forming a stop during a radial movement of the radial shaft.

Abstract: A flight control device of an aircraft including a support, an action member attached to the support rotating freely around a primary axis, a rotary device including a stator, rotatably connected to the support around a secondary axis, and a rotor rotating freely relative to the stator around the secondary axis, the rotary device applying a force sensing torque on the rotor relative to the stator around the secondary axis, and a mechanical reducing gear, which connects, with a reduction ratio, rotation of the action member with rotation of the rotor, the mechanical reducing gear including a screw-nut system with rolling elements, including a screw, attached to the rotor, connected in rotation to the rotor around the secondary axis, and a nut fixed in rotation around the secondary axis relative to the stator and helically connected with the screw around and along the secondary axis via the rolling elements.

Abstract: A yaw system for a wind turbine can have a yaw bearing with an outer bearing ring, an inner bearing ring, and a plurality of yaw rollers rotationally disposed between the outer and inner bearing rings so as to allow relative motion between the outer and inner bearing rings. A bi-directional braking assembly having an outer clutch ring attached to the outer bearing ring, an inner clutch ring attached to the inner bearing ring, and a plurality of brake rollers rotationally and slidably disposed between the inner clutch ring and at least one locking ramp adjacent the outer clutch ring. A plurality of spring members can extend from either ring projections or activation projections to each brake roller. An activation ring can slidably position the plurality of brake rollers into one of a locked position or unlocked position to prevent yaw rotation in an undesired direction.

Abstract: A propeller assembly with at least two propeller blades that are interconnected by associated connection means, the associated connection means defining a common pitch axis for the at least two propeller blades in operation, each one of the at least two propeller blades comprising associated leading and trailing edges that define a respective chord and quarter chord line thereof, wherein the common pitch axis is arranged with a predetermined offset relative to the quarter chord line of each one of the at least two propeller blades, and wherein the associated connection means is adapted to enable, at least in operation in a non-axial inflow field, a passive pitch adjustment of the at least two propeller blades around the common pitch axis.

Abstract: Control methods and systems of a wind turbine belonging to an off-shore wind park that use, in case of malfunction of the load measuring system, one of the following pitch vectors for the calculation of the individual pitch command of each blade: the pitch vector being applied at the same time in one wind turbine of the wind park where the load measuring system works properly a mean value of the pitch vectors being applied at the same time in a group of wind turbines of the wind park where the load measuring system works properly; the pitch vector resulting from a control law, obtained from historic records of the wind turbine when the load measuring system worked properly, defining the pitch vector as a function of at least the wind speed V, if the former pitch vectors are not available.

Abstract: The invention describes a mechanism to cause an actuator born on a rotating shaft to modulate backwards and forwards independently of the motion of the rotating shaft. This mechanism is then used to realize a controllable-pitch blade fan. The axial modulating mechanism is achieved by mounting a thread on the rotating shaft onto which an axial modulator, with a cylindrical cavity having a mating thread, is mounted; magnets induce the axial modulator to rotate independently of the shaft's rotation in turn causing the axial modulator to move linearly along the shaft. This mechanism's linear motion is then used to force blades rotatably mounted on the shaft to rotate and consequently vary their pitch.

Abstract: A feedback sensor system is provided. The feedback sensor system includes a first ring rotatable about an axial direction and a second ring also rotatable about the axial direction. The first ring includes one or more first ring features and the second ring includes one or more second ring features. The feedback sensor system also includes a sensor directed at the surface of the first ring for sensing a parameter influenced by the one or more first ring features and the one or more second ring features. The sensor may determine a position of the first ring relative to the second ring by sensing the parameter.

Abstract: Improvements Relating to Wind Turbines A wind turbine apparatus and a method of operating said wind turbine to maintain the load on the rotor blade below a predetermined threshold level is provided. The method comprises: measuring load at a root end of the rotor blade; measuring an acceleration at a location on the rotor blade outboard from the root end, the acceleration being caused by transient loads acting on the rotor blade; and controlling the wind turbine based upon the measured load and the measured acceleration to maintain the load on the rotor blade below a predetermined threshold level.

Abstract: The present invention generally relates to a runner unit of a tidal power plant, and more particular to a device for reversing a blade of the runner unit. The device according to the invention is lighter and more efficient with respect to known solutions which involve articulated mechanisms as it is based on an auxiliary servomotor including a reciprocating linear rack which acts on the blade to be reversed.

Abstract: The invention relates to a rotor-blade extension body for use with a rotor blade of a rotor of a wind turbine. The rotor-blade extension body is elongate and is realized, for example, as a steel tube segment. There is a lift-generating element mounted on the circumference of the rotor-blade extension body.

Abstract: A pivot for an air propeller blade, the pivot including a rotary support for mounting radially on a propeller hub while being suitable for pivoting about a pivot axis; and a blade support including a housing for receiving a blade root and at least one arm extending laterally relative to the pivot axis and carrying a flyweight forming a counterweight; the arm and its flyweight presenting the general geometrical shape of a spherical cap.

Abstract: A propeller blade assembly includes a spar extending along a propeller blade axis and an outer sleeve surrounding the spar portion at a root end of the rotor blade assembly. The spar is adhesively bonded to the outer sleeve at an interface portion. A spar maximum diameter along the interface portion is larger than an outer sleeve minimum diameter along the interface portion. A method of assembling a propeller blade includes installing an outer sleeve over a spar at a root end of the spar, the spar a not fully cured composite component, and urging the spar into compressive conformance with the outer sleeve at an interface portion of the propeller blade assembly. A spar maximum diameter along the interface portion is larger than an outer sleeve minimum diameter along the interface portion. The spar is cured thereby adhesively bonding the spar to the outer sleeve at the interface portion.

Abstract: A control device of the pitch of blades of a rotor of a propeller is provided. The control device includes: a radial shaft; a pivot connected to the blade, the rotation of the radial shaft driving the rotation of the pivot for the modification of the pitch of the blade; an insert fixed rigidly to the pivot so as to block their relative displacement, the radial shaft being configured to drive in rotation the insert; at least one peg passing through the insert and the pivot for transmission of the rotation of the insert to the pivot; and a heat insulation element arranged between the insert and the pivot, whereof the thermal conductivity is less than the thermal conductivity of the pivot and of the radial shaft.

Abstract: A method of controlling a wind turbine comprising blades attached to a rotor hub for rotation in a rotor plane and a control system for individually pitching the blades relative to the hub. The method comprises dividing the rotor plane into a number of sectors, determining the individual sectors for each blade during the rotation by means of an azimuth angle sensor, and obtaining blade sensor data from a blade sensor on an individual blade relating to a sector, and comparing the obtained data with data relating to the same sector and representing blade sensor data on other blades. When an event is detected in a given sector, an individual pitch contribution is determined in the sector, and the blades are then pitched according to this individual pitch contribution for that given sector at least partly during passage of the sector.

Abstract: A pitch system for a wind turbine rotor, comprising a first bearing and a second bearing, each provided with an outer race, an inner race, and at least one row of rolling elements, the first and second bearings being adapted to be arranged between a hub and a blade root portion or extender, to allow rotation of the blade with respect to the hub, wherein the first bearing is adapted to be arranged nearer to the hub than the second bearing in the axial direction, the pitch system further comprising an intermediate body arranged between the first bearing and the second bearing in the axial direction, said intermediate body comprising at least a blade-side part extending between the race of the first bearing that is associated with the blade and the race of the second bearing that is associated with the blade.

Abstract: A device for feeding fluid to a hydraulic actuator for controlling a pitch of fan blades of a two-propeller turboprop, the device including: a fluid manifold secured to a rotor of the turboprop and including a cylindrical portion including at least two fluid-circulation grooves, each presenting an outlet orifice; a fluid-admission support secured to a stationary portion of the turboprop and including a cylindrical portion including at least two distinct fluid passages opening to fluid-admission tubes and each leading radially into one of the fluid-circulation grooves of the manifold; and a tub constrained to rotate with the fluid manifold and including a cylindrical portion including at least two fluid-flow channels, each fed with fluid by a respective one of the outlet orifices of the fluid dispenser, each fluid-flow channel leading to a respective chamber of a control actuator.

Abstract: A method for alleviating rotor asymmetric loads in a variable-speed wind turbine having pitch and torque control means comprising the following steps: providing a control law that determines the pitch to be applied individually to each wind turbine blade for counteracting rotor asymmetric loads (such as wind shear, upflow, yaw misalignment) using wind speed and wind direction measurements at the wind turbine, values of the wind features that cause rotor asymmetric loads and configuration parameters of the wind turbine (whether real-time values or statistical values at the wind turbine site), said pitch to be added to the collective pitch ?0; implementing said control law in the wind turbine control means. The invention also refers to a wind turbine control system arranged for implementing said method.

Abstract: A method and apparatus for moving a blade of a rotorcraft. The method comprises operating the rotorcraft and applying a torque to an elongate member connected to a tip portion of the blade during operation of the rotorcraft using a tip actuation mechanism that is external to the blade and associated with the elongate member such that the tip portion of the blade rotates about an axis through the blade.

Abstract: A rotor for coupling to a shaft is provided. The rotor includes a space frame hub having a central portion coupled to the shaft and a first structural member coupled to said central portion, wherein the first structural member has a first length. The rotor further includes a first blade coupled to the first structural member and having a tip end spaced from the shaft at a second length that is longer than the first length.

Abstract: A rotor for use in an aircraft includes an inner hub; and a plurality of blades arranged around the inner hub, each of the plurality of blades comprising an inner structural member; an outer blade shell surrounding the inner structural member; and a centering block located at a base of the inner structural member proximal to the inner hub, wherein the centering block is located between a first lateral portion of the inner structural member and a second lateral portion of the inner structural member, wherein the centering block is further connected to the outer blade shell, and wherein the centering block allows the outer blade shell to rotate about an axis approximately corresponding to the inner structural member.

Abstract: A system and method for preventing a rotor blade from striking a tower of the wind turbine is disclosed. The system includes a pitch adjustment mechanism, at least one electrical switch, and a mechanically-actuated positional switch. The pitch adjustment mechanism is configured to rotate the rotor blade about a pitch axis. Further, the pitch adjustment mechanism includes a motor and a brake. The electrical switch is configured with the motor, the brake, or both. The mechanically-actuated positional switch is fixed within a hub of the wind turbine. Further, the positional switch is configured with the electrical switch such that if the rotor blade rotates to an unsafe region, the positional switch is configured to trigger the electrical switch to implement one of tripping power to the motor of the pitch adjustment mechanism or actuating the brake of the pitch adjustment mechanism.

Abstract: Device for supplying oil under pressure to a linear actuator of a turbine engine, this actuator comprising an internal fixed portion and an external movable portion and means for regulating and supplying oil to chambers of the actuator, these regulating means being mounted radially outside the movable portion of the actuator, and the fixed portion of the actuator comprising on its upstream end portion oil passage channels of which the outlets open radially outwards, the device further comprising an oil distribution ring which is mounted on the upstream end portion of the fixed portion and which comprises internal conduits of which the inlets communicate with the outlets of the channels of the fixed portion and the outlets open axially downstream and are connected to the regulating means.

Abstract: A propeller assembly is provided including a plurality of blades arranged in diametrically opposed pairs. Each of the plurality of blades has an electrical deicer located thereon. The propeller assembly also includes a slip ring, and a stationary brush arranged in contact with the slip ring. The brush is configured to transfer electrical power from a power source to the slip ring. A movable portion of an actuator is configured to sequentially couple the electrical deicers of each pair of blades to the rotating slip ring.

Abstract: Disclosed is a blade pitch controller for a small-scale wind power generation system. Movable segments are integrally formed on an outer circumferential surface of the movable block, have moving grooves, and move backward and forward along with the movable block. Pitch adjustment pieces have adjustment pins formed at one end of each thereof, key grooves into which blade shafts are fixedly inserted are formed in the middles thereof, and pitch angles of blades are changed by angles changed when the movable block moves backward and forward. Pitch adjustment cylinders are coupled to fixing pieces formed at one end of each of the pitch adjustment pieces by hinges so as to be able to be located near the adjustment pins, are compressed when the movable block moves backward, and cause the pitch adjustment pieces to return to an original state after being compressed.

Abstract: A method of adjusting a pitch angle of a rotor blade of a rotor of a wind turbine is provided. The method comprises varying the pitch angle of the rotor blade during wind operation of the wind turbine from a starting angle to reach a limit angle (?1, ?2) at which the rotor blade and/or an operational value (P) of the wind turbine reaches a predefined threshold limit (P1/2; ?1, ?2), deriving a safe angle (?3, ?4) dependent on the limit angle (?1, ?2), operating the rotor blade at the safe angle (?3, ?4) or an angle from the safe angle (?3, ?4) away from the limit angle (?1, ?2). A pitch angle adjustment system is also provided for the same purpose.

Abstract: A wind turbine rotor is provided which comprises a hub (2) and at least one blade (20) supported by said hub (2). The blade (20) comprises a first blade section (3) and a second blade section (4), wherein said first blade section (3) is mounted to said hub (2) stationary with respect to said hub (2) and said second blade section (4) is supported by said first blade section (3) rotatably adjustable about a longitudinal axis of said blade (20) wherein said second blade section (4) is supported by said first blade section (3) by at least two bearings (7a, 7b) which are spaced with respect to said longitudinal axis of said blade (20).

Abstract: A wind turbine includes a rotor comprising multiple blades mounted on a hub, MIMUs mounted on each blade for sensing parameter signals thereof, and a control system. The control system includes a wind speed calculation unit, a wind shear calculation unit, a pitch angle compensation command calculation unit, and a pitch control unit. The wind speed calculation unit is used for calculating wind speeds at the blades based at least on the sensed parameter signals. The wind shear calculation unit is used for calculating a characteristic shear exponent based at least on the calculated wind speeds. The pitch angle compensation command calculation unit is used for calculating pitch angle compensation commands of the blades based at least on the calculated characteristic shear exponent. The pitch control unit is used for adjusting the pitch angles of the blades based on the calculated pitch angle compensation commands.

Abstract: A method for controlling an individually pitched wind turbine during shutdown is disclosed, the wind turbine comprising at least three wind turbine blades (1a, 1b, 1c). In response to a shutdown command for stopping operation of the wind turbine, a blade parameter of each of the wind turbine blades (1a, 1b, 1c), e.g. pitch angle, bending moment or blade acceleration, is determined. The blade parameters of the wind turbine blades (1a, 1b, 1c) are compared, and a shutdown strategy for the wind turbine is selected from a group of two or more predefined shutdown strategies, based on the comparing step. Finally, the wind turbine blades (1a, 1b, 1c) are moved towards a feathered position in accordance with the selected shutdown strategy.

Abstract: A mounting system for mounting a blade to a rotor body includes a pitch control mechanism including an anchor and a pitch change rod extending radially outwardly from the anchor to join to a base of the blade. The anchor and the rod are rotatable about the longitudinal axis of the rod to vary the blade pitch. The pitch control mechanism further includes a torque-transmitting formation between the blade and the anchor such that pitch-varying torque can be transmitted to the blade through the torque-transmitting formation while allowing relative radial movement between the blade and the anchor. The system includes a primary bearing formation, which transmits blade centrifugal loads to the rotor body while accommodating variation of the blade pitch, and secondary bearing formation, which transmits pitch change mechanism centrifugal loads to the rotor body while accommodating rotation of the anchor and the rod during variation of the blade pitch.