Abstract: A generator for a wind turbine is disclosed. The generator comprises a rotor configured to rotate about a rotational axis, and at least one stator arranged next to the rotor. Each stator comprises at least one flux-generating module facing the rotor but spaced therefrom, thereby forming an air gap between the rotor and each flux-generating module. Each stator also comprises at least one bearing unit, each bearing unit comprising a body defining a cavity with an open end facing the rotor. The generator further comprises a source of pressurized fluid communicating with each bearing unit, and the body of each bearing unit directs the fluid towards the rotor to help maintain the air gap between the rotor and each flux-generating module. Thereby the air gap between the rotor and the flux-generating modules is controlled by means of the fluid bearing units. The invention further provides a wind turbine comprising such a generator.

Abstract: A method of operating a wind turbine having a bearing assembly, a shaft received therein, and at least one sub-system capable of altering a dynamic state of the wind turbine includes monitoring at least one parameter indicative of a load on the shaft; comparing the at least one parameter to a threshold criteria; and when the at least one parameter meets the threshold criteria, altering the dynamic state of the wind turbine to reduce the load on the shaft; and/or altering the state of the bearing assembly to better accommodate the load on the shaft. A control system for the wind turbine includes a controller operatively coupled to the bearing assembly and the at least one sub-system, and at least one sensor for monitoring at least one parameter indicative of a load on the shaft. The controller signals the sub-system or the bearing assembly when the threshold criteria is met.

Abstract: A bearing assembly for a wind turbine includes a bearing housing and a bearing surface defining a passageway configured to receive a shaft. The bearing surface includes a stationary portion and a movable portion, the movable portion being defined by a movable member coupled to the bearing housing. The movable member is movable between a first position, wherein the movable portion is flush with the stationary portion such that the bearing surface is smooth, and a second position wherein the movable portion is spaced from the stationary portion to define a fluid cavity in the bearing surface. A method of operating a plain bearing assembly includes operating the plain bearing assembly as a hydrostatic plain bearing during low dynamic conditions and operating the plain bearing assembly as a hydrodynamic plain bearing during high dynamic conditions.

Abstract: A generator (5) for a wind turbine (1) is disclosed. The generator (5) comprises a rotor (3) configured to rotate about a rotational axis, and at least one stator (4) arranged next to the rotor (3). Each stator (4) comprises at least one flux-generating module (9) facing the rotor (3) but spaced therefrom, thereby forming an air gap between the rotor (3) and each flux-generating module (9). Each stator (4) also comprises at least one bearing unit (12), each bearing unit (12) comprising a body (16) defining a cavity (14) with an open end facing the rotor (3). The generator (5) further comprises a source of pressurized fluid communicating with each bearing unit (12), and the body (16) of each bearing unit (12) directs the fluid towards the rotor (3) to help maintain the air gap between the rotor (3) and each flux-generating module (9). Thereby the air gap between the rotor (3) and the flux-generating modules (9) is controlled by means of the fluid bearing units (12).

Abstract: Electrical machines, wind turbines, and methods of operating an electrical machine. The electrical machine includes first and second rotatable members that are configured to convert mechanical energy received from the wind turbine rotor into electrical energy. The first rotatable member is coupled with the wind turbine rotor and the second rotatable member is coupled by a gear train with the wind turbine rotor. The gear train, which is driven by rotation of the wind turbine rotor, rotates the second rotatable member relative to the first rotatable member in a direction counter to a direction of rotation of the first rotatable member. The electrical machine may be a generator of the wind turbine.

Abstract: A plain bearing assembly for mounting a blade to a hub of a wind turbine includes an outer member mountable to one of the blade or hub, and an inner member mountable to the other of the blade or hub and movable relative to the outer member. The plain bearing further includes fluid cavities associated with one of the outer or inner member and arranged to confront the other of the outer or inner member. The fluid cavities are coupled to a pressure source for establishing a pressurized fluid film between the inner and outer members. A method includes monitoring at least one parameter of the fluid film, comparing the at least one parameter to a threshold criteria, and altering a dynamic state of the wind turbine and/or altering the state of the blade bearing assembly if the threshold criteria is exceeded.

Abstract: A method of operating a wind turbine having a bearing assembly, a shaft received therein, and at least one sub-system capable of altering a dynamic state of the wind turbine includes monitoring at least one parameter indicative of a load on the shaft; comparing the at least one parameter to a threshold criteria; and when the at least one parameter meets the threshold criteria, altering the dynamic state of the wind turbine to reduce the load on the shaft; and/or altering the state of the bearing assembly to better accommodate the load on the shaft. A control system for the wind turbine includes a controller operatively coupled to the bearing assembly and the at least one sub-system, and at least one sensor for monitoring at least one parameter indicative of a load on the shaft. The controller signals the sub-system or the bearing assembly when the threshold criteria is met.

Abstract: Electrical machines, wind turbines, and methods of operating an electrical machine. The electrical machine includes first and second rotatable members that are configured to convert mechanical energy received from the wind turbine rotor into electrical energy. The first rotatable member is coupled with the wind turbine rotor and the second rotatable member is coupled by a gear train with the wind turbine rotor. The gear train, which is driven by rotation of the wind turbine rotor, rotates the second rotatable member relative to the first rotatable member in a direction counter to a direction of rotation of the first rotatable member. The electrical machine may be a generator of the wind turbine.

Abstract: A bearing assembly for a wind turbine includes a bearing housing and a bearing surface defining a passageway configured to receive a shaft. The bearing surface includes a stationary portion and a movable portion, the movable portion being defined by a movable member coupled to the bearing housing. The movable member is movable between a first position, wherein the movable portion is flush with the stationary portion such that the bearing surface is smooth, and a second position wherein the movable portion is spaced from the stationary portion to define a fluid cavity in the bearing surface. A method of operating a plain bearing assembly includes operating the plain bearing assembly as a hydrostatic plain bearing during low dynamic conditions and operating the plain bearing assembly as a hydrodynamic plain bearing during high dynamic conditions.

Abstract: A plain bearing assembly for a wind turbine includes a bearing housing having a passageway configured to receive a shaft and a bearing surface defining the passageway and having a cylindrical configuration. The bearing surface includes lower and upper portions defined relative to a first midline plane and first and second sides defined relative to a second midline plane. A plurality of fluid cavities is in the bearing surface, wherein at least one fluid cavity is located in the lower portion and at least one fluid cavity is located in the upper portion. The at least one cavity in the lower portion includes first and second pairs of longitudinally spaced fluid cavities on the first and second sides of the bearing surface respectively. A wind turbine having such a plain bearing assembly is also disclosed.

Abstract: A plain bearing assembly for a wind turbine includes a bearing housing having a passageway configured to receive a shaft and a bearing surface defining the passageway and having a generally spherical configuration. The bearing surface includes lower and upper portions defined relative to a first midline plane and first and second sides defined relative to a second midline plane. A plurality of fluid cavities is in the bearing surface including a first group of fluid cavities located at a first longitudinal position and a second group of fluid cavities located at a second longitudinal position. The first group of fluid cavities defines a cavity pattern that is different than the cavity pattern defined by the second group of fluid cavities. A wind turbine having such a plain bearing assembly is also disclosed.

Abstract: A plain bearing assembly for mounting a blade to a hub of a wind turbine includes an outer member mountable to one of the blade or hub, and an inner member mountable to the other of the blade or hub and movable relative to the outer member. The plain bearing further includes fluid cavities associated with one of the outer or inner member and arranged to confront the other of the outer or inner member. The fluid cavities are coupled to a pressure source for establishing a pressurized fluid film between the inner and outer members. A method includes monitoring at least one parameter of the fluid film, comparing the at least one parameter to a threshold criteria, and altering a dynamic state of the wind turbine and/or altering the state of the blade bearing assembly if the threshold criteria is exceeded.