A rotor hub of a wind turbine comprising a hub housing, which has a plurality of connecting flanges, which are each adapted for connection of a rotor blade, wherein each of the rotor blades is coupled to a pitch drive for rotating the rotor blade, wherein the pitch drive is connected to an arrangement of electrical control devices, which are adapted to control the pitch drive. The arrangement of the control devices is provided in a module as a structural unit, the module being connected as a whole to the hub housing.

A fail-safe actuation system comprising an actuator having first and second chambers, a working circuit with a motor/pump device configured to actuate the actuator in an operative state, and a safety circuit configured to move the actuator into the safety position in a failure state, the safety circuit having a tank that holds pressurized fluid and that, in the failure state, is automatically connected to the first chamber via a switching valve, and having a drain valve that, in the failure state, is moved into a through-flow position in order to drain fluid out of the second chamber, the safety circuit configured such that, in the operative state, an inflow into the actuator—in a manner that is decoupled from the tank—is established by the working circuit, and, in the failure state, an inflow from the tank into the first chamber—in a manner that is completely decoupled from the working circuit—is created by the safety circuit, whereby a short-circuit fluid connection is provided between the first and second chambers that, in the failure state, is through-connected in order to generate a short-circuit flow between the first and second chambers.

A fluidic rotor rotary machine has a rotor comprising at least one blade (4) mounted on an arm (2) rotating about a main axis (1) of the rotor, the rotor being held by a support structure (5) in an orientation such that said axis (1) is essentially perpendicular to the fluid flow direction, the blade (4) being pivotally mounted about a rotational axis (3) parallel to the main axis (1), the machine being characterized in that it comprises means for generating a relative rotational movement of the blade (4) relative to the arm (2) at the rotational axis (3), thereby varying the blade angle, said means comprising an eccentric mechanism rotating on said blade rotational axis. Application in particular to propellers and generators operating according to Lipp-type or Voith-Schneider-type kinematics, with possible mode switching.

In one aspect, a dual pitch bearing configuration for coupling a rotor blade to a hub of a wind turbine. The dual pitch bearing configuration including a first pitch bearing and at least one additional pitch bearing. The first pitch bearing and the and at least one additional pitch bearing are coupled to opposed surfaces of a static shaft. The at least one additional pitch bearing is disposed radially a distance L.sub.R and axially a distance L.sub.A from the first pitch bearing along the static shaft. The dual pitch bearing is disposed radially within a blade root of the rotor blade. The dual pitch bearing configuration minimizing moment loading on the first pitch bearing and the at least one additional pitch bearing. A wind turbine including the dual pitch bearing configuration is further disclosed.

An axial impeller has a tubular housing mounted on bearings for rotation. The housing is capable of engaging a motor or generator directly or through a drive belt. Interior turbine blades are mounted on the housing wall. The blades may be hinged so they can rotate between a retracted position adjacent to the wall and an extended radial position. Rods penetrate the wall to position the blades between retracted and extended positions. When extended, the blades may be rotated to propel a fluid through the housing; and when retracted natural fluid flow is less restricted.

The present disclosure is directed to a method for responding to a friction coefficient signal of a pitch bearing of a pitch drive mechanism of a wind turbine and/or for controlling the pitch drive mechanism(s) and/or a bank of ultracapacitors. The method and system include: accessing high-frequency measurement data of the at least one pitch bearing; estimating, via a torque balance model implemented by a controller, a frictional torque of the at least one pitch bearing based, at least in part, on the high-frequency measurement data; estimating, via the controller, a friction coefficient signal of the at least one pitch bearing based, at least in part, on the frictional torque; comparing the friction coefficient signal with a friction threshold; determining whether the friction coefficient signal deviates from the friction threshold based, at least in part, on the comparison; and, if so, acting.

A floating electrical power generator having a three-dimensional (3D) flow passageway configured for increasing the water flow on the paddle wheel to increase the power output.

A wind turbine comprises a hub, a blade rotatably mounted to the hub, and a pitch system. The pitch system includes a support, a first drive configured to rotate the blade relative to the support, a second drive configured to rotate the support relative to the hub. The support is configured to be selectively fixed relative to the blade and the hub such that the first or second drive may be used to pitch the blade. A method of pitch corresponding to this operation is provided.

A novel approach to optimizing control accuracy of pitch angle of the blades of an airplane propeller or wind turbine rotor by using laminated rubber (elastomeric) bearings in place of rolling element bearings so that the former's smooth torque vs. deflection characteristics minimally influence the balance of passive control torques upon the pitch axis due to calibrated springs and forces resulting from rotation speed and/or aerodynamic drag.

There is provided a turbine including a hub body including a shaft for transmitting the torque generated by the turbine to a driven machine, a plurality of turbine blades carried by the hub body and rotatable about their longitudinal axes, an adjusting body in an interior of the hub body, arranged as a spherical link chain extending coaxially to the shaft and rotatable about a shaft axis of the shaft, and a guide rod chain for each of the plurality of turbine blades, including a smooth spherical shell having a uniform surface and two guide rods, including a first guide rod having a first end linked to the adjusting body via a swivel joint and a second guide rod having a first end linked to a second end of the first guide rod via the swivel joint.