A modular wind turbine blade is described. The modular wind turbine blade comprises first and second blade modules having spar caps embedded within their outer shells. The spar caps taper in thickness resulting in tapered recesses being defined in the outer shells. The tapered recesses in the first and second blade modules are aligned when the modules are placed end-to-end to form a continuous double-tapered channel. A connecting member having a double-tapered structure is bonded in the channel to connect the modules together. The invention also provides a mould for making the blade modules in which the mould surface includes a protruding elongate feature having a tapered portion configured to form the recesses in the outer shells. During layup and moulding of the outer shells, spar caps are supported on top of the tapered portion of the elongate feature.

A marine turbine and tower combination in which the turbine is mountable on the tower, The turbine has a co-operating member to interact with the tower to enable the turbine to be mounted on the tower in a pre-determined alignment. In one arrangement, the support tower comprises a substantially horizontal thruster plate mounted on top of the tower. The thruster has a central aperture to receive a downwardly directed stud on the turbine the thruster plate providing lateral support for the turbine. The stud has a vertical reaction interface around a lower part of the stud which is supported vertically by a reaction ring mounted on the tower.

Provided is a wind turbine including a rotor with a hub and several rotor blades arranged at the hub with the rotor blades being rotatable around an axis relative to the hub by a pitch bearing arrangement, whereby each rotor blade extends into the hub with a blade section, with the pitch bearing arrangement including a first and a second rolling bearing being spaced apart from each other in the direction of the axis and arranged between the blade sections and the hub.

A rotor blade for a wind turbine is provided, wherein the rotor blade includes serrations along at least a portion of the trailing edge section of the rotor blade. The serrations include a first tooth and at least a second tooth, and the first tooth is spaced apart from the second tooth. The area between the first tooth and the second tooth is at least partially filled with porous material such that generation of noise in the trailing edge section of the rotor blade is reduced. Furthermore, the embodiments relate to a wind turbine including at least one such a rotor blade.

A wind turbine blade for a wind turbine is a shell structure of a fiber-reinforced composite and comprises a root region and an airfoil region. The root region has a ring-shaped cross section and comprises a cylindrical insert 7 embedded in the fiber-reinforced polymer so as to substantially follow the circumference of the root region. The cylindrical insert is provided with a number of mutually spaced threaded bores 12, 15 in a first end 9 thereof being accessible from the outside.

A root bushing for a blade root of a wind turbine rotor blade, including a cylindrical bushing body and a flat contact body is provided. The contact body is provided on a face of the bushing body. This has the advantage that due to the provision of the contact body, the contact area between the root bushing and the pitch bearing is increased. In another embodiment, the root bushing includes a central bore which protrudes through the bushing body and the contact body. In another embodiment, an outer wall of the bushing body is provided with a connection structure for connecting the root bushing to a composite material of the wind turbine rotor blade.

A wind turbine blade is provided, including two planks joined with each other in a longitudinal direction of the planks at joining surfaces by a butt joint, wherein each plank includes a main portion with a wedge-shaped recess and a wedge-shaped portion filling the recess, each wedge-shaped portion has a respective one of the joining surfaces and is tapered from its joining surface in a direction away from its joining surface, and a stiffness of a material of the wedge-shaped portions is smaller than a stiffness of a material of the main portions. By having the wedge-shaped portions, the load is transferred to the surrounding material over a larger area which reduces the stress concentration.

A bushing (42, 92) for connecting a wind turbine blade (20) to a rotor hub (18) of a wind turbine (10) including a main body (44, 94) defining a connecting end of the bushing (42, 92) for receiving a fastener (130) for securing the blade (20) to the rotor hub (18), a tubular extension (46, 96) extending distally from the main body (44, 94) and defining a tip end of the bushing (42, 92) and a central bore (52, 102) extending from the connecting end to the tip end of the bushing (42, 92) and defining a central axis (94, 104) of the bushing (42, 92). The tubular extension (46, 96) includes one or more tapered or cylindrical sections (74,124) and a tip section (76, 126) distal of the one or more tapered or cylindrical sections (74, 124) and adjacent the tip end. The tip section (76, 126) includes an outer surface and an inner surface that are substantially parallel to each other and substantially parallel to the central axis (94, 104) of the bushing (42, 92).

A wind turbine blade bushing system for arrangement in a root end of a wind turbine blade is described. The wind turbine blade bushing system comprises a threaded element for retaining a mounting bolt for a wind turbine blade, the threaded element being formed from a first material; and an anchor element for arrangement at the root end of the wind turbine, wherein the anchor element acts to at least partly retain the threaded element in the wind turbine blade, the anchor element being formed from a second material. The first material has a higher strength and higher fracture toughness than the second material.

According to the present invention there is provided a method of assembling a modular wind turbine blade comprising first and second blade modules connectable together at an interface to form at least part of the modular wind turbine blade. The method comprises providing a first blade module and a second blade module. Each blade module comprises an outer shell defining an outer surface of the blade module, a connecting region of the outer shell defining an interface end of the blade module, and a longitudinally-extending spar cap embedded in the outer shell. The spar cap has a tapered end portion in the connecting region in which the thickness of the spar cap decreases towards the interface end of the blade module such that a tapered recess is defined in the outer surface of the blade module. The method further comprises arranging the first and second blade modules end-to-end with the tapered recesses aligned to define a bridge recess. The tapered recess of the first blade module defines a first end of the bridge recess, and the tapered recess of the second blade module defines a second end of the bridge recess. The method further comprises arranging a stack of layers in the bridge recess and spanning the interface between the first and second blade modules. The stack of layers comprises a plurality of pre-cured layers interleaved with pre-preg interlayers. The pre-preg interlayers comprise fibrous material that is pre-impregnated with uncured resin. The method further comprises applying heat to the stack of layers in the bridge recess such that the resin in the pre-preg interlayers mobilises in the bridge recess. The method further comprises curing the resin to integrate the pre-cured layers with each other to form a spar bridge spanning the interface, the spar bridge serving to connect the spar caps of the first and second blade modules.