The invention relates to a device (100), a system (10) and a method for modifying the cross section of a tower section (1) of a wind turbine, wherein the tower section comprises a flange (4) located at an end (3) of the tower section having a plurality of through holes (5) spaced around its circumference for securing said tower section to another wind turbine section. The method comprises securing tensioning mechanism (14) to each of a pair of said plurality of through holes in the flange of the tower section, said pair of holes being generally opposed; and applying a tensile force between said pair of holes in the flange of the tower section.

A method for mounting rotor blades of a wind turbine is provided. The wind turbine has a rotor hub with three rotor blade ports. A rotor blade is to be mounted to each of the three rotor blade ports. A mounting arm is fastened to a first rotor blade port. The mounting arm has a first section and a second section, which are coupled with each other via a hinge, so that the angle between the first and second sections can be varied. The hub is turned until the first rotor blade port is in a 90° position. A first end of the first section of the mounting arm is fastened to the first rotor blade port of the rotor hub. The rotor hub is turned with the help of the mounting arm, until the second rotor blade port is in a 270° position. The angle between the first and second sections of the mounting arm is varied while turning the rotor hub. A first rotor blade is lifted, so that the first rotor blade is horizontally mounted to the second rotor blade port of the rotor hub.

A method for mounting rotor blades of a wind turbine is provided. The wind turbine has a rotor hub with three rotor blade ports. A rotor blade is to be mounted to each of the three rotor blade ports. A mounting arm is fastened to a first rotor blade port. The mounting arm has a first section and a second section, which are coupled with each other via a hinge, so that the angle between the first and second sections can be varied. The hub is turned until the first rotor blade port is in a 90° position. A first end of the first section of the mounting arm is fastened to the first rotor blade port of the rotor hub. The rotor hub is turned with the help of the mounting arm, until the second rotor blade port is in a 270° position. The angle between the first and second sections of the mounting arm is varied while turning the rotor hub. A first rotor blade is lifted, so that the first rotor blade is horizontally mounted to the second rotor blade port of the rotor hub.

A method (100) of mounting a blade (22) to or unmounting a blade (22) from a rotor hub (20) of a wind turbine (10), the wind turbine (10) comprising a tower (12) and a nacelle (16) mounted on the tower (12), the rotor hub (20) being coupled to the nacelle (16), the method (100) comprising gripping the blade (22) using a gripper (50), the gripper (50) comprising gripping members (58) configured for gripping the blade (22) and teeth (60) protruding from the gripping members (58), wherein gripping comprises inserting the teeth (60) of the gripper (50) into receptacles (78) of the blade (22); and rotating the blade (22) about a rotation axis (54) perpendicular to a longitudinal blade axis (53) using a blade rotation device (52) of the gripper (50), wherein the teeth (60) are configured for transmitting an axial load (57) of the blade (22) between the blade (22) and the gripping members (58).

A method (100) of mounting a blade (22) to or unmounting a blade (22) from a rotor hub (20) of a wind turbine (10), the wind turbine (10) comprising a tower (12) and a nacelle (16) mounted on the tower (12), the rotor hub (20) being coupled to the nacelle (16), the method (100) comprising gripping the blade (22) using a gripper (50), the gripper (50) comprising gripping members (58) configured for gripping the blade (22) and teeth (60) protruding from the gripping members (58), wherein gripping comprises inserting the teeth (60) of the gripper (50) into receptacles (78) of the blade (22); and rotating the blade (22) about a rotation axis (54) perpendicular to a longitudinal blade axis (53) using a blade rotation device (52) of the gripper (50), wherein the teeth (60) are configured for transmitting an axial load (57) of the blade (22) between the blade (22) and the gripping members (58).

Power generation systems comprising modular blades and a secondary power source, and methods of manufacturing the same employing additive manufacturing. Various features of the system are described, including a rotor, spoke and support base. A slip gear assembly is described to coordinate the wiring of the secondary power sources.

Power generation systems comprising modular blades and a secondary power source, and methods of manufacturing the same employing additive manufacturing. Various features of the system are described, including a rotor, spoke and support base. A slip gear assembly is described to coordinate the wiring of the secondary power sources.

Protection for a cable, piping or tubing comprises a bend stiffener. This includes at least one element comprising a tubular wall having a substantially smooth inner surface, which defines circumferential recesses along at least part of its length. Each recess has an open end at the circumference of the wall, a base, and sloping sides that are closer to each other at the base than at the open end. Each recess has a depth of no more than 50% of the thickness of the tubular wall. The bend stiffener may include a number of such elements connected together. The cable protection may also include a clamp attached to the bend stiffener.

Protection for a cable, piping or tubing comprises a bend stiffener. This includes at least one element comprising a tubular wall having a substantially smooth inner surface, which defines circumferential recesses along at least part of its length. Each recess has an open end at the circumference of the wall, a base, and sloping sides that are closer to each other at the base than at the open end. Each recess has a depth of no more than 50% of the thickness of the tubular wall. The bend stiffener may include a number of such elements connected together. The cable protection may also include a clamp attached to the bend stiffener.

A set of units for assembly to form a wind turbine nacelle. The nacelle comprises a rotor-supporting assembly and generator, and a power conversion assembly and the set of units comprises a main unit arranged to be connected to a wind turbine tower and housing the rotor-supporting assembly and the generator, and at least two different auxiliary units each housing an operative component forming part of the power conversion assembly. To allow different wind turbine configurations, one of the auxiliary units can be selected from the at least two auxiliary units and assembled with the main unit to form the nacelle.