A pitch controlled wind turbine comprising a tower, a nacelle mounted on the tower, a hub mounted rotatably on the nacelle, and at least three wind turbine blades is disclosed. Each wind turbine blade extends between a root end connected to the hub via a pitch mechanism, and a tip end. The wind turbine further comprises at least three blade connecting members, each blade connecting member extending between a connection point on one wind turbine blade and a connection point on a neighboring wind turbine blade, the connection points being arranged at a distance from the root end and at a distance from the tip end of the wind turbine blade. The wind turbine further comprises at least three pre-tension members, each pre-tension member being connected to one of the blade connecting members and to a hub part, the pre-tension members thereby providing pre-tension in the blade connecting members.

A pitch controlled wind turbine (1) comprising a tower (2), a nacelle (3) mounted on the tower (2), a hub (4) mounted rotatably on the nacelle (3), and at least three wind turbine blades (5) is disclosed. Each wind turbine blade (5) extends between a root end (6) connected to the hub (4), and a tip end (7). The wind turbine (1) further comprises at least three blade connecting members (8), each blade connecting member (8) extending between a connection point (9) on one wind turbine blade (5) and a connection point (9) on a neighbouring wind turbine blade (5). The wind turbine blades (5) each comprises an inboard blade part (5a) comprising the root end (6) and an outboard blade part (5b) comprising the tip end (7), the inboard blade part (5a) and the outboard blade part (5b) being connected to each other at a split position (10). The split position (10) is arranged between the root end (6) and the connection point (9).

A pitch controlled wind turbine comprising a tower, a nacelle mounted on the tower, a hub mounted rotatably on the nacelle, and at least three wind turbine blades is disclosed. Each wind turbine blade extends between a root end connected to the hub via a pitch mechanism, and a tip end. The wind turbine further comprises at least three blade connecting members, each blade connecting member extending between a connection point on one wind turbine blade and a connection point on a neighboring wind turbine blade, the connection points being arranged at a distance from the root end and at a distance from the tip end of the wind turbine blade. The wind turbine further comprises at least three pre-tension members, each pre-tension member being connected to one of the blade connecting members and to a hub part, the pre-tension members thereby providing pre-tension in the blade connecting members.

A pitch actuator for a wind turbine pitch system, the pitch actuator having an actuator rod, a drive end of which is defined by a clevis fork arrangement having first fork member and a second fork member that extend in a direction along a rod axis and terminate at a tip end. The first and second fork members define respective clevis openings for receiving a clevis pin therethrough, said clevis openings each having an opening perimeter profile comprising: a first perimeter section defined by a leading circular arc that is centred on the rod axis and oriented in the direction of the tip end of the fork members, the circular arc defining a nominal radius and a central angle of less than 120 degrees, and second and third flared perimeter sections that flank respective sides of the first perimeter section, each of which define an enlarged clearance zone with respect to at least part of an imaginary circle defined by the nominal radius of the first perimeter section. A benefit of the invention is that the enlarged clearance zones defined by the flared perimeter sections create an area where there is no contact between the perimeter of the openings and the outer surface of the clevis pin. This provides a stress relieving function since deformation of the openings in use, due to force applied along the axis of the actuator rod, does not create a point of stress combined with sliding or rubbing movement with the sides of the clevis pin, thereby reducing wear and fatigue. The invention extends to a pitch system including such a pitch actuator and a wind turbine incorporating such a pitch system.

A pitch controlled wind turbine (1) comprising a tower (2), a nacelle (3) mounted on the tower (2), a hub (4) mounted rotatably on the nacelle (3), and at least three wind turbine blades (5) is disclosed. Each wind turbine blade (5) extends between a root end (6) connected to the hub (4), and a tip end (7). The wind turbine (1) further comprises at least three blade connecting members (8), each blade connecting member (8) extending between a connection point (9) on one wind turbine blade (5) and a connection point (9) on a neighbouring wind turbine blade (5). The wind turbine blades (5) each comprises an inboard blade part (5a) comprising the root end (6) and an outboard blade part (5b) comprising the tip end (7), the inboard blade part (5a) and the outboard blade part (5b) being connected to each other at a split position (10). The split position (10) is arranged between the root end (6) and the connection point (9).

A pitch actuator for a wind turbine pitch system, the pitch actuator having an actuator rod, a drive end of which is defined by a clevis fork arrangement having first fork member and a second fork member that extend in a direction along a rod axis and terminate at a tip end. The first and second fork members define respective clevis openings for receiving a clevis pin therethrough, said clevis openings each having an opening perimeter profile comprising: a first perimeter section defined by a leading circular arc that is centred on the rod axis and oriented in the direction of the tip end of the fork members, the circular arc defining a nominal radius and a central angle of less than 120 degrees, and second and third flared perimeter sections that flank respective sides of the first perimeter section, each of which define an enlarged clearance zone with respect to at least part of an imaginary circle defined by the nominal radius of the first perimeter section. A benefit of the invention is that the enlarged clearance zones defined by the flared perimeter sections create an area where there is no contact between the perimeter of the openings and the outer surface of the clevis pin. This provides a stress relieving function since deformation of the openings in use, due to force applied along the axis of the actuator rod, does not create a point of stress combined with sliding or rubbing movement with the sides of the clevis pin, thereby reducing wear and fatigue. The invention extends to a pitch system including such a pitch actuator and a wind turbine incorporating such a pitch system.

An impeller for wind turbines comprises a rear ring having a central axis. The impeller comprises a front ring having an inner peripheral surface. The front ring is arranged coaxially and is slidably associated with the rear ring. The front ring is movable along the central axis and switches between a close configuration and a spaced apart configuration, with respect to the rear ring. The impeller comprises a plurality of blades connected to the front ring and defining a variable-pitch propeller. The blades being adjustable between a minimum pitch when the front ring is in the close configuration and a maximum pitch when the front ring is in the spaced apart configuration.

A system for a wind turbine nacelle having a shaft housing, a blade shaft that extends through the shaft housing and is rotatable relative to the shaft housing, a blade holder connected to the blade shaft, and an outer bearing between the blade shaft and the shaft housing includes a conical spring. The conical spring engages a portion of the outer bearing to exert a preload force on the outer bearing. The system further includes a backstop surrounding the blade shaft and having an interference fit with the blade shaft and a pin extending through the blade shaft and the blade holder. The pin is positioned to prevent the blade shaft from moving relative to the backstop.

An impeller for wind turbines comprises a rear ring having a central axis. The impeller comprises a front ring having an inner peripheral surface. The front ring is arranged coaxially and is slidably associated with the rear ring. The front ring is movable along the central axis and switches between a close configuration and a spaced apart configuration, with respect to the rear ring. The impeller comprises a plurality of blades connected to the front ring and defining a variable-pitch propeller. The blades being adjustable between a minimum pitch when the front ring is in the close configuration and a maximum pitch when the front ring is in the spaced apart configuration.

Disclosed is a method and a device for independently pitching of a wind turbine. The method includes: driving a first gear using a pitch motor, such that a second gear meshed with the first gear drives a bearing inner ring to rotate to drive a paddle of a wind turbine connected to an outer side of the bearing inner ring, the bearing inner ring being connected to a root of the paddle of the wind turbine; inflating and pressurizing, using an air pump, an airbag to discharge a lubricating fluid from an interior of the airbag through discharge holes and connecting tubes; and the lubricating fluid flowing into an annular flow chamber through connecting holes, and flowing, through seepage holes, into a rotational gap between a bearing outer ring and the bearing inner ring.