A method for joining rotor blade segments of a rotor blade includes providing a first blade segment defining a concave cross-sectional shape having at least one internal flange. The method also includes providing a second blade segment having at least one external flange. Further, the method includes positioning the internal flange(s) of the blade segment internal of the external flange(s) of the second blade segment at a joint. Moreover, the method includes placing at least one inflatable internal bladder within an inner cavity of the rotor blade at the joint. In addition, the method includes inflating the internal bladder(s) so as to provide internal pressure thereto so as to align the internal flange(s) with the external flange(s) and to maintain contact between the internal flange(s) and the external flange(s). Thus, the method also includes securing the first and second blade segments together while maintaining the internal pressure via the internal bladder(s).

A wind turbine powertrain assembly including a gearbox coupled to an electrical power generator for a wind turbine. The power generator comprises a stator at a radially outward position and a rotor in a radially inward position, wherein the rotor comprises a cylindrical field structure that is configured to rotate about a generator rotor axis, and wherein the rotor is configured to define a central hollow portion. The rotor further comprises a rotor support frame connected to and structurally supporting the cylindrical field structure, wherein the rotor support frame comprises: a rotor connection flange attaching the rotor support frame to the cylindrical field structure, a gearbox connecting flange connecting the rotor support frame to an output drive shaft of the gearbox, and a transition section extending between the rotor connection flange and the gearbox connection flange, the transition section defined at least in part by one or more stepping regions, the or each stepping region shaped to define a surface that is inclined at an angle of less than 30 degrees to the rotor axis. Advantageously, the stepping regions provide an integrated platform inside the hollow portion on which service personnel can stand to work inside the generator.

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 and related system for installing a wind turbine blade to a rotor head of a nacelle located on top of a tower of a wind power generator, the method comprising hoisting the blade up the tower to a substantially vertical orientation, where movement thereof up the tower is guided by at least one carriage intermediate the blade and the tower and removably secured to the blade, the at least one carriage contacting with an outer surface or surfaces of the tower as the blade is being hoisted.

An assembly for determining the electrical angle of a rotor in an electrical machine is provided, such as a wind turbine generator. The assembly includes: (a) an encoder having an encoder wheel configured to contact a surface of the rotor to obtain relative rotor rotation information based on rotation of the encoder wheel, (b) an electrical angle observer configured to provide an absolute electrical angle, and (c) a processing device coupled to communicate with the encoder and the electrical angle observer and configured to determine the electrical angle of the rotor based on the relative rotor rotation information and the absolute electrical angle. Furthermore, a wind turbine generator including such an assembly, and a method of determining the electrical angle of a rotor in an electrical machine, such as a wind turbine generator, are provided.

A load mitigation arrangement of a non-mounted rotor blade, includes at least one actuatable lift-modification device arranged on a surface of the rotor blade; a monitor configured to estimate the magnitudes of loads acting on the non-mounted rotor blade; a controller configured to actuate the lift-modification device on the basis of the estimated magnitudes to mitigate the loads acting on the non-mounted rotor blade. Further provided is a rotor blade assembly, and a method of performing load mitigation on a non-mounted rotor blade.

A system for lowering blades without using a crane, which solves a de alignment and insertion problem resulting from the tilt and coning of the blade along the first/last 200-400 mm and the problem of space inside the hub. The system is characterized in that it moves the vertical load of the blade by 90, converting it into a horizontal load actuated by at least two hydraulic elements and by aligning the center of gravity (CoG) of the blade vertically with the center of a bearing by using cables and pulleys. Each of the systems is disposed inside the hub, in the bottom part thereof and secured to the fixed part. The system comprises three main parts: the pulley, the hydraulic element and an axis-shift element secured with pins, one of the pins being fixed and the other adjustable. The cable bordering the end pulley comprises connectors before the point at which same passes through interior pulleys, which distribute the load evenly between the two cables.

A wind turbine powertrain assembly including a gearbox coupled to an electrical power generator for a wind turbine. The power generator comprises a stator at a radially outward position and a rotor in a radially inward position, wherein the rotor comprises a cylindrical field structure that is configured to rotate about a generator rotor axis, and wherein the rotor is configured to define a central hollow portion. The rotor further comprises a rotor support frame connected to and structurally supporting the cylindrical field structure, wherein the rotor support frame comprises: a rotor connection flange attaching the rotor support frame to the cylindrical field structure, a gearbox connecting flange connecting the rotor support frame to an output drive shaft of the gearbox, and a transition section extending between the rotor connection flange and the gearbox connection flange, the transition section defined at least in part by one or more stepping regions, the or each stepping region shaped to define a surface that is inclined at an angle of less than 30 degrees to the rotor axis. Advantageously, the stepping regions provide an integrated platform inside the hollow portion on which service personnel can stand to work inside the generator.