Disclosed is a method for dismantling a wind turbine gearbox (15) from a main shaft (7) in the nacelle (3) of a wind turbine (1), wherein a first end (11) of the main shaft (7) is connected to the gearbox (15) in a connection cavity (22) of the gearbox (15) and a second end (12) of the main shaft (7) is connected to a rotor (4) of the wind turbine (1). The method comprises the steps of: arranging a hydraulic connection plug (13) in a centre channel (14) of a second end (37) of a gearbox shaft (21) of the gearbox (15), wherein a first end (20) of the gearbox shaft (21) is arranged at the connection cavity (22) on a first side (23) of the gearbox (15) and wherein the second end (37) of the gearbox shaft (21) is arranged at a second side (24) of the gearbox (15) opposite the first side (23), securing the hydraulic connection plug (13) and the gearbox shaft (21) against axial displacement in a direction towards the second side (24) of the gearbox (15), connecting a hydraulic pump (25) to the hydraulic connection plug (13), and pumping liquid into the connection cavity (22) by means of the hydraulic pump (25) to force the main shaft (7) out of the connection cavity (22). Furthermore, use of the method is disclosed.

Disclosed is a method for dismantling a wind turbine gearbox (15) from a main shaft (7) in the nacelle (3) of a wind turbine (1), wherein a first end (11) of the main shaft (7) is connected to the gearbox (15) in a connection cavity (22) of the gearbox (15) and a second end (12) of the main shaft (7) is connected to a rotor (4) of the wind turbine (1). The method comprises the steps of: arranging a hydraulic connection plug (13) in a centre channel (14) of a second end (37) of a gearbox shaft (21) of the gearbox (15), wherein a first end (20) of the gearbox shaft (21) is arranged at the connection cavity (22) on a first side (23) of the gearbox (15) and wherein the second end (37) of the gearbox shaft (21) is arranged at a second side (24) of the gearbox (15) opposite the first side (23), securing the hydraulic connection plug (13) and the gearbox shaft (21) against axial displacement in a direction towards the second side (24) of the gearbox (15), connecting a hydraulic pump (25) to the hydraulic connection plug (13), andpumping liquid into the connection cavity (22) by means of the hydraulic pump (25) to force the main shaft (7) out of the connection cavity (22). Furthermore, use of the method is disclosed.

An apparatus and method for removing or installing a bearing unit at the downwind end of the bedplate in wind turbine uses a frame erected at the downwind end of the bedplate. The frame has cradle members located such that the bearing unit can be slid out of the bedplate and supported on the cradle members, or supported on the cradle members and pushed into the bedplate.

A generator for a direct driven wind turbine configured to convert kinetic energy of a main shaft of the wind turbine into electrical energy. The generator includes a generator rotor connectable to the main shaft of the wind turbine and a generator stator, the generator includes a generator housing on which the generator stator is arranged. The generator housing includes a front side facing towards a rotor head of the wind turbine in an installed state of the generator and a rear side facing away from the rotor head in the installed state of the generator. The generator includes at least one front generator bearing arranged at the front of the generator housing and a rear generator bearing arranged at the rear of the generator housing.

An apparatus and method for removing or installing a bearing unit at the downwind end of the bedplate in wind turbine uses a frame erected at the downwind end of the bedplate. The frame has cradle members located such that the bearing unit can be slid out of the bedplate and supported on the cradle members, or supported on the cradle members and pushed into the bedplate.

A wind turbine nacelle including an outer cover defining an interior volume within which is housed a powertrain assembly comprising: a gearbox including an input shaft and an output shaft which are aligned on a common rotational axis, an electrical power generator connected to the output shaft of the gearbox. The power generator includes a generator cabinet that encloses, in an internal chamber, a stator at a radially outward position and a rotor in a radially inward position, the rotor being rotatable about the common rotational axis. The rotor comprises: a cylindrical field structure coupled to a rotor support frame; a gearbox connection flange that couples to the gearbox output shaft by a first fixing array; wherein the generator cabinet is provided with an opening that permits maintenance personal to gain access fully inside the internal chamber, and wherein the internal chamber is configured to allow maintenance personnel to access at least the first fixing array that couples the gearbox output shaft to the gearbox connection flange from a position fully inside the internal chamber.

A wind turbine nacelle including an outer cover defining an interior volume within which is housed a powertrain assembly comprising: a gearbox including an input shaft and an output shaft which are aligned on a common rotational axis, an electrical power generator connected to the output shaft of the gearbox. The power generator includes a generator cabinet that encloses, in an internal chamber, a stator at a radially outward position and a rotor in a radially inward position, the rotor being rotatable about the common rotational axis. The rotor comprises: a cylindrical field structure coupled to a rotor support frame; a gearbox connection flange that couples to the gearbox output shaft by a first fixing array; wherein the generator cabinet is provided with an opening that permits maintenance personal to gain access fully inside the internal chamber, and wherein the internal chamber is configured to allow maintenance personnel to access at least the first fixing array that couples the gearbox output shaft to the gearbox connection flange from a position fully inside the internal chamber.

Stators for use in electric machines and methods for refurbishing the same. One method for refurbishing a stator for use in an electric machine includes at least partially disassembling the stator to provide access to a plurality of stator windings connected in a four-circuit star connection having three turns per coil, and reconfiguring the stator such that the plurality of stator windings are connected in a four-circuit delta connection having five turns per coil.

A wind turbine drivetrain is provided, including a low-speed shaft; a high-speed assembly including a planetary gearbox and a generator; a coupling assembly including a first annular part connected to the low-speed shaft, a second annular part connected to a first stage of the planetary gearbox, and a cylindrical intermediate part extending between the annular parts, a drivetrain housing arranged to enclose the low-speed shaft and the coupling assembly; having an outer access opening formed in the drivetrain housing; and an inner access opening formed in the intermediate part of the coupling assembly and arranged to align with the outer access opening to facilitate access to the interior of the coupling assembly. Also, further described is a method of performing a maintenance procedure on such a wind turbine drivetrain.

A repair device is provided for a wind turbine having a bearing with damaged teeth driven by a motor. The repair device includes a carrier for connection to the bearing and radially aligned with the damaged teeth. A gear train is mounted on the carrier for creating a torque transfer path from the motor to non-damaged teeth of the bearing.