In a first aspect, a system for rotating an unbalanced direct drive wind turbine is provided. The system includes an auxiliary converter and a power source coupled to the auxiliary converter, wherein the auxiliary converter is configured to supply a current to the wind turbine generator for generating a torque to rotate the hub. In a further aspect, a method of rotating an unbalanced hub of a direct drive wind turbine is provided. In a yet further aspect, a method of installing a blade in a hub of a direct drive wind turbine is provided.

An impeller locking device for a wind generator is provided. The impeller locking device includes a locking hole formed on an impeller connecting disc, and a locking pin configured to fit into the locking hole. The locking pin is connected with a base of the wind generator; and when the locking pin is locked in the locking hole, a radial clearance is provided between the locking pin and the locking hole. When the axes of the locking pins and the locking holes are deviated radially, the locking pins can also be inserted into the locking holes, so that radial constraints of the locking pins and the locking holes are eliminated. A wind generator adopting the impeller locking device is further provided.

A rotor lock system (20) for securing a main shaft assembly of a wind turbine (2) in a substantially stationary position, the main shaft assembly comprising a main rotor shaft (16) supported by a base frame (14), and the rotor lock system comprising: a locking disk (22), associated with the main rotor shaft (16), and provided with a plurality of locking apertures (26); and a locking unit (24) comprising a first end (28) arranged to engage with the locking disk (22), and a second end supported by a mounting feature (38) associated with the base frame (14), wherein the locking unit (24) is configured to be adjustable relative to the mounting feature (38) so that the first end (28) moves linearly with respect to the mounting feature.

A rotor rotating device includes at least two rotating units; a movable end of a telescoping cylinder in each rotating unit is provided with a pin; the pin is releasably secured on a rotor. A control method for the rotor rotating device includes: dividing the at least two rotating units into two groups; first removing pins of a first group of rotating units from the rotor, and then re-securing the pins at another positions on the rotor; and after the pins of all the rotating units are re-secured, changing the state of the telescoping cylinders of all the rotating units, and driving the rotor to turn relative to a machine base. In this way, all the rotating units are sequentially unlocked, moved to a next working station, and re-locked on the rotor. A control device, and a rotor rotating system are further provided.

A rotor lock assembly for locking a rotor of a wind turbine includes at least one removable rotor lock. The removable rotor lock has a housing comprising an opening and a mounting portion, a pin shaft positioned within the opening, and a locking mechanism. The opening extends from a first end to a second end thereof. The mounting portion is adapted for mounting to a bearing housing adjacent to a rotor lock plate of the rotor.

A rotor turning device for balancing a rotor secured atop a tower of a wind turbine during installation and/or repair of one or more rotor blades of the wind turbine includes a hydraulic drive mechanism for operably engaging with a brake disc of the wind turbine. The brake disc is positioned adjacent to a gearbox of the wind turbine. The rotor turning device also includes a mounting device for securing the rotor turning device adjacent to the brake disc of the wind turbine. Thus, when the hydraulic drive mechanism engages the brake disc, the rotor is rotated to a desired position so as to position one or more rotor blades of the wind turbine in a balanced configuration.

A method for performing uptower maintenance of a wind turbine in order to replace the main bearing on the turbine shaft is disclosed. Embodiments of this method to perform maintenance may include installing a rotor lock to resist rotation of the main shaft during maintenance, providing a lifting device in order to elevate the main shaft, removing the main bearing from its main bearing housing, and installing a replacement split main bearing. A crane may also be installed uptower to assist in the maintenance.

A generator, in particular a generator of a wind turbine, comprising a rotatably mounted generator rotor, a generator stator which corresponds to the generator rotor and which has a support structure for fixing in the wind turbine, and at least one arresting device which is configured to be coupled in between the generator rotor and the generator stator in such a way that there is a force flow between the generator rotor and the generator stator and which is adapted in the coupled state to arrest the generator rotor in a predetermined position relative to the generator stator. The arresting device has a damping element which is variable in shape such as to deform as a result of the force flow between the generator rotor and the generator stator.

A rotor rotation control system for a wind turbine and a control method thereof are provided. The control system includes a rotation unit configured to drive a rotor of the wind turbine to rotate relative to an engine base of the wind turbine, a driving unit configured to drive the rotation unit, and a processor configured to determine a bending moment load switching position on a rotating shaft of the rotor, and output an adjustment instruction to the driving unit based on the bending moment load switching position.

A control method for a hydraulic control turning system of a generator rotor includes: establishing a length relationship table between multiple hydraulic cylinders of the hydraulic control turning system; selecting a reference hydraulic cylinder; acquiring current lengths of the multiple hydraulic cylinders when the multiple hydraulic cylinders are located at error correction positions; and adjusting lengths of the other hydraulic cylinders corresponding to a next driving stroke to conform with the length relationship table. With such an arrangement, the accumulated dimension error between the hydraulic cylinders may be dynamically corrected during the turning operation, thereby ensuring that the turning pins are accurately aligned with the pin holes in the generator, and the corresponding turning operation is performed after the generator set is locked. Based on this, a control device for a hydraulic control turning system of a generator rotor is further provided.