The disclosure relates to a main shaft of a wind turbine with mounting segments. The main shaft includes a shaft portion and a disc portion. The disc portion includes a coupling surface, a hollow portion, and an alignment portion. The alignment portion is characterized by one or more mounting segments coupled with the alignment portion. The mounting segments are configured to align a component of the wind turbine with the central axis of the main shaft. Further, the one or more mounting segments are coupled to the alignment portion using at least one fastening device. The mounting segments have a thickness t that may be constant or varied based on the component 32 of the wind turbine coupled to the main shaft.

A damping system for a heave compensator for an off-shore oil rig includes a hydraulic cylinder having a piston and a housing. The hydraulic cylinder is configured for accepting a hydraulic fluid. There is a flow passage for restricting the flow of the hydraulic fluid during movement of the piston in the housing. The hydraulic fluid is a magnetic fluid and the damping system includes a magnetic fluid management system for controlling a magnetic field at the flow passage. A heave compensator including such a damping system, and a method for controlling the damping of a heave compensator are also disclosed, the method including subjecting a magnetic fluid to a magnetic field at a flow passage for restricting the flow of the magnetic fluid.

A Special Personal Cooling device that acts as an air distribution system for use by an individual to prevent heat stress and fatigue. It is a lightweight plenum manifold which spreads, throws, and distributes a flow of pressurized air about the upper or lower body of an individual, the flow of air itself capable of cooling the skin directly or cooling the clothing worn by the individual by providing a pressurized air stream that evaporates moisture and perspiration. The device is made of a resilient and durable materials configured as a belt system; a power system; a fan system; a means to mechanically and integrally secure the fan system, power system and belt system together; and an electrical control system for controlling the power from the battery to the motor and fan.

Provided is a direct drive wind turbine that includes: a hub, at least one blade fixed to the hub, a nacelle on which the hub is rotatably mounted for rotating about a rotational axis, the nacelle including an electrical generator connected to the hub in order to receive rotational energy from the hub, a tower on which the nacelle is mounted, and a lightning protection arrangement including a plurality of protection conductors extending between the at least one blade and the tower, the plurality of protection conductors including at least a first protection conductor mounted on an external surface of the electrical generator.

A yaw assembly for a wind turbine may include a bushing configured for securement within a yaw cylinder containing a yaw piston and a yaw pad having a first side configured for engagement with a slew ring of the wind turbine and a second side configured for engagement with the yaw piston, a thrust stem engaged with the bushing and configured to apply force to the yaw pad against the slew ring, the thrust stem biased away from the yaw pad by one or more springs residing within the yaw piston, and an anti-rotation collar disposed at an interface between the thrust stem and the yaw piston, the anti-rotation collar including a flange extending from a bottom-center portion thereof, the flange disposed between the one or more springs and a bottom end of the yaw piston.

A hydroelectric power generation apparatus includes a hydroelectric power generation module, a beam as a supporting part, and a fixing part. The hydroelectric power generation module includes a rotary blade and a power generator that generates power by rotation of the rotary blade. The supporting part supports the hydroelectric power generation module. The fixing part fixes the supporting part to a water channel. The fixing part includes a bolt to press a surface of a wall portion of the water channel to fix the supporting part to the water channel. The hydroelectric power generation apparatus can dispense with a work performed around the water channel to install the apparatus and also be relocated easily and inexpensively.

A hydroelectric power generation apparatus includes a hydroelectric power generation module, a supporting part, and a bar. The hydroelectric power generation module includes a rotary blade and a power generator that generates power by rotation of the rotary blade. The supporting part supports the hydroelectric power generation module. The supporting part can be installed at a water channel. The bar is connected to the supporting part to protrude from the supporting part. With one end of the bar closer to the supporting part or a portion of the supporting part serving as a center, the other end of the bar opposite to one end of the bar can be pivoted to switch a first state to a second state and vice versa.

A water turbine device is provided which can move a water turbine from a use position to a nonuse position with a light force, and which has a simplified structure. An intermediate portion of a suspension support rod for suspending a water turbine immersed in a flowing water in a waterway is pivotally attached to a platform provided on the waterway with a horizontal shaft, and a power generation device as a balance weight is provided at the free end of the suspension support rod, and the water turbine is rotatable around the horizontal shaft between the use position where the water turbine is immersed in a flowing water and the nonuse position above the flowing water.

A wind turbine (1) comprising a tower structure comprising a main tower part (2) extending along a substantially vertical direction and at least two arms(3) is disclosed. Each arm (3) extends away from the main tower part (2) along a direction having a horizontal component, and the arms (3) are arranged to perform yawing movements. Two or more energy generating units (4) are mounted on the tower structure in such a manner that each arm (3) of the tower structure carries at least one energy generating unit(4), each energy generating unit (4) comprising a rotor (5) with a hub carrying a set of wind turbine blades(6). The main tower part (2) is provided with a cable supporting structure (7) allowing power cables (8) of a power grid to be mounted on the main tower part (2).

A method for installing a plurality of rotor blades to a rotatable hub secured atop a tower of a wind turbine includes providing a counterweight assembly having, at least, a mounting assembly and a counterweight mass secured at a distal end of the mounting assembly. The method also includes securing the mounting assembly at a first position on the hub of the wind turbine such that the counterweight mass biases the hub to rotate about its rotation axis in a first direction. Further, the method includes consecutively installing the plurality of rotor blades onto the hub of the wind turbine. Moreover, the method includes adjusting a position of the counterweight mass between each consecutive installation of the plurality of rotor blades to continuously change a center of gravity of the hub and maintain a balanced rotor of the wind turbine during installation of the plurality of rotor blades.