A system may include a massive flywheel including a rotatable mass component and one or more axles coupled with the rotatable mass component. A system may include a magnetic lift component having one or more magnets positioned around a center perforation, the one or more axles passing through the center perforation in the magnetic lift component, the one or more magnets pulling the massive flywheel toward the magnetic lift component. A system may include a support structure coupled with the magnetic lift component, the support structure holding the magnetic lift component at a stationary location relative to the support structure. A system may include one or more bearings coupled with the support structure and the one or more axles to maintain the one or more axles at an axis of rotation.

Counterweight system for a wind turbine comprising a hub mounted to a nacelle such that the hub is rotatable around a rotation axis with respect to the nacelle. The counterweight system comprises: a mechanical unit comprising a fixed part and a rotatable part, the fixed part being mountable to the hub in such a way that the rotatable part is rotatable with respect to the hub substantially around the rotation axis of the hub; a drive unit for causing rotation of the rotatable part; a beam coupled to the rotatable part at a first point of the beam in such a way that the beam is arranged substantially perpendicular to the rotation axis of the hub; and a counterweight mass coupled to the beam at a second point of the beam. A method of mounting a blade to a hub by using said counterweight system is also provided.

Disclosed is a method for lifting and lowering blades without using a crane, which uses an aligning and inserting device to solve the problem caused by the tilt and coning of the first/last 200-400 mm of the blade. The device comprises at least one hoist (4) and a pair of cables (5) coordinated by a pulley (10) and screwed to a bearing (12) by means of connecting elements at the ends thereof. The cables (5) are screwed diametrically opposite and as close as possible to the centre of gravity (CG) of the blade. After the initial descent, the blade is secured and a stiffening plate (20) is added to the blade root (13), and the lowering device, formed by a drumless hoist (18) and a set of pulleys (19), is used to lower the blade by means of a passing cable (22) joined to the plate (20). A crane disposed on the ground moves an auxiliary sling placed on the tip (23) of the blade and helps to navigate the transition piece (24) and bottom part (25) of a tower.

A method for installation of a transition piece on a monopile foundation of an offshore wind turbine along a common axis extending in a longitudinal direction is performed from a floating installation vessel. Buffer elements are arranged around an inner circumference of the transition piece and/or the monopile structure. The transition piece is lifted and lowered onto the monopile structure by use of a crane, and landed onto the monopile structure through the use of the buffer elements. A number of hydraulic cylinder jacks for circumferential alignment of bolt holes are provided in the transition piece and monopile, and alignment tools are used for alignment of the flanges provided on each of the transition piece and the monopile. The transition piece is lifted and the buffer elements are removed after which the transition piece is lowered onto the monopile, and bolts are tensioned fix the transition piece to the monopile.

The application describes an apparatus for and a method of mounting wind turbine blades on a wind turbine tower. A number of guide rods are provided in the vicinity of the blade root and hub for connection to corresponding socket sections. The guide rods and socket sections are provided on respective ones of a wind turbine blade and a wind turbine hub to facilitate connection of one to the other. The guide rods and the sockets may be provided on the same or on different ones of the blade or hub. The guide rods and sockets allow the blade to be positioned at the hub in the correct rotational orientation to facilitate connection of the necessary fasteners.

A method for assembling a rotor bearing of a wind turbine, includes the method steps: providing a rotor shaft; providing an outer ring element; providing individual sliding bearing pads; positioning the rotor shaft and the outer ring element relative to one another, such that the rotor shaft is arranged in its desired axial position within the outer ring element; subsequent individual insertion of the sliding bearing pads in an intermediate space between the rotor shaft and the outer ring element.

A flywheel system may include one or more massive plates. A system may include two or more clamping plates including a bottom clamping plate and a top clamping plate, the one or more massive plates being located between the two or more clamping plates. A system may include two or more axles including a top axle and a bottom axle, the bottom axle being physically disconnected from the top axle. A system may include a plurality of fasteners coupling the top clamping plate with the bottom clamping plate, the plurality of fasteners applying a clamping force on the one or more massive plates using at least one of the two or more clamping plates and the two or more axles.

A system may include a stacking device having a base portion and one or more walls, the base portion having a first axle receiver that holds a first axle at a first defined position, the one or more walls extending from the base portion, the stacking device receiving one or more flywheel plates onto the first axle. A system may include a clamping device adapted to couple with the stacking device using one or more alignment mechanisms, the clamping device including a second axle receiver that holds a second axle at a second defined position, the first defined position and the second defined position being in line when the clamping device is coupled with the stacking device.

The present disclosure relates to methods for rotating a locked rotor of a wind turbine in case of an imbalance in a rotor plane of the rotor, comprising: rotating the rotor using an inching tool to apply torque on a drive train of the wind turbine to reduce the imbalance in the rotor plane; and removing a locking pin from a locking disc operatively connected to the rotor after reducing the imbalance in the rotor plane. The methods further comprise estimating a direction of a torque load due to the imbalance in the rotor plane using one or more sensors, and impeding the inching tool to apply torque on the drive train of the wind turbine in the estimated direction of the torque load due to the imbalance. The present disclosure further relates to inching tools and to methods for installing rotor blades on a hub of a wind turbine.

A flywheel system may include one or more massive plates. A system may include two or more clamping plates including a bottom clamping plate and a top clamping plate, the one or more massive plates being located between the two or more clamping plates. A system may include two or more axles including a top axle and a bottom axle, the bottom axle being physically disconnected from the top axle. A system may include a plurality of fasteners coupling the top clamping plate with the bottom clamping plate, the plurality of fasteners applying a clamping force on the one or more massive plates using at least one of the two or more clamping plates and the two or more axles.