An underwater structure including a power generation apparatus including a main body; a mounting portion connected to the main body defining a mounting axis; a connection carrier, a connector mounted on the connection carrier; and an actuation mechanism in communication with the connection carrier. The structure further includes a support structure adapted for engagement with a bed of a body of water; a support housing; a support connection carrier attached to the support housing; and a support connector mounted on the support connection carrier. The mounting portion and the support housing are adapted to cooperate with one another for mounting of the power generation apparatus on the support structure. The connection carrier is releasably engageable with the support connection carrier, such that the connection carrier is moveable between an engaged position and a disengaged position.

The present invention describes a floating yawing spar buoy current/tidal turbine. The spar includes a spreader above the rotor(s) with the spreader tips connected to fore and aft cable yokes that transition to opposing mooring lines connected to anchors on the seabed. The spreader comprises a yaw motor, which drives gears that engage with a ring gear fixed to the outer perimeter of the spar.

The new wing or blade design for wingtip device, rotor, propeller, turbine, and compressor blades with energy regeneration can be used to generate lift, propel vehicles more efficiently, compress fluids more efficiently, harness energy more efficiently. This system can be used as a wing, as a wingtip device, as a propeller for aircraft or boats or any vehicle moving through a fluid, in a compressor, as a rotor for wind turbine or helicopter, in a gas turbine. The new wing or blade design for wingtip device, rotor, propeller, turbine, and compressor blades with energy regeneration is a series of low aspect ratio wings placed in parallel with gaps between them connected by smaller wings that are placed in the gaps to harness the energy and produce forces; the gaps are shaped to decelerate the fluid and/or accelerate the fluid by varying the cross-sectional area of the gaps. Even if the small aspect ratio makes those wings inefficient, the strength of the vortices is smaller in the gaps.

A method of operating a hydraulic system of a plant to resume operation from a minimum operating temperature of the plant, the hydraulic system includes a plurality of electronically operated valves, the method including a first stage in which the valves are controlled to cycle fluid from a tank through a bypass valve and directly back to the tank until the temperature of the fluid in the tank has reached a first interim level; and a second stage in which the valves are controlled to cycle fluid from the tank through the pressure lines of the hydraulic system and back to the tank until the temperature of the fluid has reached a desired operating level. Further, a hydraulic system and a wind turbine include a rotor blade pitching arrangement with such a hydraulic system.

A device and method for rotating a rotor of a wind power generator and a wind power generator are provided. The device includes at least two rotating units, and each of the rotating units includes a telescopic cylinder, a mounting base configured to connect a fixed end of the telescopic cylinder to a stand of the wind power generator, and detachably connected to the stand; and a pin arranged at a movable end of the telescopic cylinder, configured to be releasably fixed to the rotor, and configured to drive the rotor to rotate relative to the stand by a stroke movement of the telescopic cylinder.

A method for detaching or installing a rotor blade from or to a hub of a wind turbine includes positioning the rotor blade toward a ground location between a three o'clock position and a nine o'clock position. The method also includes mounting a mechanical arm to an uptower location of the wind turbine. Further, the mechanical arm includes a torqueing tool at a distal end thereof. Thus, the method also includes removing or installing, via the torqueing tool, each of the plurality of hub fasteners so as to detach or attach the rotor blade from or to the hub.

A clamping apparatus for positioning a main bearing of a wind turbine includes a push component arranged between a main flange of a main shaft of the wind turbine and a cover of the main bearing. Further, the clamping apparatus includes a spacer plate located within a gap between the cover and the main bearing. As such, the push component is configured to apply a force to the cover so as to push the spacer plate against the main bearing such that the main bearing is pushed into and secured in place.

A servo actuator is provided which may comprise a controller configured to control a plurality of solenoid valves based upon an output signal. The plurality of solenoid valves may be used to control the position of the object. For example, a set of solenoid valves, of the plurality of solenoid valves, may be configured to conduct fluid from a tank into a first chamber of the cylinder, conduct fluid from the tank into a second chamber of the cylinder, conduct fluid from the second chamber of the cylinder into a first solenoid valve and/or conduct fluid from the first chamber of the cylinder into the first solenoid valve. The first solenoid valve, of the plurality of solenoid valves, may be configured to conduct fluid from the set of solenoid valves into a vent valve based upon a pulse width modulation (PWM) signal received from the controller.

A pitch actuator for a wind turbine pitch system, the pitch actuator having an actuator rod, a drive end of which is defined by a clevis fork arrangement having first fork member and a second fork member that extend in a direction along a rod axis and terminate at a tip end. The first and second fork members define respective clevis openings for receiving a clevis pin therethrough, said clevis openings each having an opening perimeter profile comprising: a first perimeter section defined by a leading circular arc that is centred on the rod axis and oriented in the direction of the tip end of the fork members, the circular arc defining a nominal radius and a central angle of less than 120 degrees, and second and third flared perimeter sections that flank respective sides of the first perimeter section, each of which define an enlarged clearance zone with respect to at least part of an imaginary circle defined by the nominal radius of the first perimeter section. A benefit of the invention is that the enlarged clearance zones defined by the flared perimeter sections create an area where there is no contact between the perimeter of the openings and the outer surface of the clevis pin. This provides a stress relieving function since deformation of the openings in use, due to force applied along the axis of the actuator rod, does not create a point of stress combined with sliding or rubbing movement with the sides of the clevis pin, thereby reducing wear and fatigue. The invention extends to a pitch system including such a pitch actuator and a wind turbine incorporating such a pitch system.

A vertical axis wind turbine includes two or more cells arranged one above the other along a vertical machine axis, in which each of the cells includes a plurality of vertical blades which are arranged within the cell distributed on a concentric circle about the machine axis and which are connected so as to be able to move together on this circle and which are rotationally fixed with a main shaft, and in which the blades in the cell are each individually mounted so as to be able to rotate about a vertical axis of rotation which in particular runs internally through them. Assigned to each of the blades are means by which the blade is made to adopt, a rotational position, about its axis of rotation, which is predetermined and can be changed at any time.