Abstract: Provided is a method for controlling an electric generator of a wind turbine. The method includes varying an amplitude and/or phase angle of an harmonic current of said electric generator, while said electric generator is rotating, in particular at a known condition, measuring a signal indicative of generator vibration after and/or during varying said amplitude and/or phase angle, repeating said varying and said measuring until a predetermined requirement is met, evaluating an operating point for said electric generator by using said measured signals indicative of generator vibration in order to reduce a ripple torque of said generator, and controlling a current, in particular said harmonic current, of said electric generator in order to meet said operating point.

Abstract: A tower segment, in particular for a tower of a wind turbine, a wind turbine, and a method for manufacturing a tower segment is provided. A tower segment, in particular for a tower of a wind turbine, comprising a casing segment with an inner casing surface, an outer casing surface and a cutout for a door, wherein the inner casing surface has a first inner reinforcing portion and/or the outer casing surface has an outer reinforcing portion, wherein the inner reinforcing portion and/or the outer reinforcing portion adjoin the cutout, and the inner reinforcing portion has an inner reinforcing plate and/or the outer reinforcing portion has an outer reinforcing plate.

Abstract: A tower segment, in particular for a tower of a wind turbine, a wind turbine, and a method for manufacturing a tower segment is provided. A tower segment, in particular for a tower of a wind turbine, comprising a casing segment with an inner casing surface, an outer casing surface and a cutout for a door, wherein the inner casing surface has a first inner reinforcing portion and/or the outer casing surface has an outer reinforcing portion, wherein the inner reinforcing portion and/or the outer reinforcing portion adjoin the cutout, and the inner reinforcing portion has an inner reinforcing plate and/or the outer reinforcing portion has an outer reinforcing plate.

Abstract: A wind turbine includes a tower (8), a nacelle (3) being connected to the tower (8), and a rotor (2) having a rotor hub (6) and a number of rotor blades (7) extending radially outwards from the rotor hub (6). The nacelle (3) includes a hollow shaft (10) and the rotor hub (6) includes a support member (11) which is connected to the hollow shaft (10) by two tapered roller bearings (14, 15) so as to be rotatable about an axis of rotation (5). The tapered roller bearings (14, 15) each have a bearing width (w) which is defined in a direction parallel to the axis of rotation (5). The tapered roller bearings (14, 15) are arranged at a distance (d) from one another which is not greater than the bearing width (w) of the tapered roller bearings (14, 15).

Abstract: A wind turbine includes a tower (8), a nacelle (3) being connected to the tower (8), and a rotor (2) having a rotor hub (6) and a number of rotor blades (7) extending radially outwards from the rotor hub (6). The nacelle (3) includes a hollow shaft (10) and the rotor hub (6) includes a support member (11) which is connected to the hollow shaft (10) by two tapered roller bearings (14, 15) so as to be rotatable about an axis of rotation (5). The tapered roller bearings (14, 15) each have a bearing width (w) which is defined in a direction parallel to the axis of rotation (5). The tapered roller bearings (14, 15) are arranged at a distance (d) from one another which is not greater than the bearing width (w) of the tapered roller bearings (14, 15).