A yaw control device for a wind turbine, including: a vertical shaft; and, a vertical wing having a leading edge, a trailing edge, a first wing surface and a second wing surface, wherein the first wing surface extends between a first edge of the leading edge to a first edge of the trailing edge and wherein the second wing surface extends between a second edge of the leading edge to a second edge of the trailing edge; wherein the vertical wing is configured to receive the vertical shaft, and wherein the vertical shaft is biased toward the leading edge of the vertical wing; and wherein the vertical wing rotates about a longitudinal axis of vertical shaft and is configured such that the leading edge faces in the direction of an approaching wing.

Even when a low stiffness blade is adopted, collision between the blade and a tower is avoided when a wind power generation apparatus is to be stopped, while an increase in the time required for the stop is suppressed. A rotor including a blade, a nacelle that supports the rotor, a tower that supports the nacelle, a pitch angle control mechanism that controls a pitch angle of the blade, and a controller that outputs a target value of the pitch angle to the pitch angle control mechanism are included. When the wind power generation apparatus is to be stopped, the controller determines the target value of the pitch angle in a feather operation of the blade such that the blade does not greatly bend toward the tower in an azimuth angle range in which the blade passes through the tower.

A yaw control device for a wind turbine. The yaw control device includes a vertical wing having a leading edge and a trailing edge. The vertical wing is configured to receive a vertical shaft. The vertical shaft is biased toward the leading edge of the vertical wing. The vertical wing rotates about a longitudinal axis of the vertical shaft.

A method for controlling a wind turbine (1) is disclosed. The wind turbine (1) comprises one or more wind turbine blades (5), each wind turbine blade (5) being connected to a blade carrying structure (4) mounted on a hub (3), via a hinge (6) at a hinge position of the wind turbine blade (5), each wind turbine blade (5) thereby being arranged to perform pivot movements relative to the blade carrying structure (4) between a minimum pivot angle and a maximum pivot angle. A maximum noise level value representing a maximum allowable noise to be generated by the wind turbine (1) is received. An optimal pair of tip speed for the wind turbine (1) and rotational speed of the wind turbine (1) is derived, based on the received maximum noise level value. The pivot angle of the wind turbine blades (5) is then adjusted to a pivot angle which results in the derived optimal pair of tip speed and rotational speed.

The present invention relates to a method for operating a wind turbine (1). The wind turbine (1) comprises one or more wind turbine blades (5), each wind turbine blade (5) being connected to a blade carrying structure (4) mounted on a hub (3), via a hinge (6) at a hinge position of the wind turbine blade (5), each wind turbine blade (5) thereby being arranged to perform pivot movements relative to the blade carrying structure (4) between a minimum pivot angle and a maximum pivot angle. The method comprises the steps of detecting an airborne object entering a predefined zone around the wind turbine (1), comparing a current tip height (H) of the wind turbine (1) to a maximum tip height value, the maximum tip height value representing a maximum allowable tip height under currently prevailing conditions. In the case that the current tip height (H) exceeds the maximum tip height value, a pivot angle (P) of wind turbine blades (5) is adjusted in order to decrease the tip height (H) of the wind turbine (1) to a value below the maximum tip height value.

The invention relates to a wind turbine comprising a floating base designed as a semi-submersible, a tower arranged on the floating base, at least two arms extending from the tower, a respective energy conversion unit arranged at the free end of each arm, and a cable system connecting the base to the energy conversion units and connecting the energy conversion units to one another in order to introduce the thrust forces acting on the tower, the arms and the energy conversion units into the base, wherein the cable system has a pre-tensioning, the value of which is greater than the loads to be expected during the operation of the wind turbine and acting against the pre-tensioning.

A wind turbine including a plurality of foldable rotor blades coupled to a rotatable hub. A mechanical actuation structure is coupled to the plurality of foldable rotor blades to move the plurality of foldable rotor blades to a deployed state, substantially perpendicular to the horizontal rotor axis, to capture kinetic energy from an incoming fluid flow and move the plurality of foldable rotor blades to a non-deployed state, substantially parallel to the horizontal rotor axis. The mechanical actuation structure including a plurality of toothed wheels, each coupled to one of the plurality of foldable rotor blades at a single fixed rotation point, a threaded rod disposed in cooperative engagement with each of the plurality of toothed wheels and a spring disposed proximate the threaded rod and configured to compensate for the static wind load on each of the plurality of foldable rotor blades. A method is also disclosed.

A fluid machine including a rotating shaft that extends parallel to a power generation shaft of a power generation unit, and that has an end coupled to the power generation shaft; a multiple rotors that are provided on the rotating shaft so as to be able to rotate in a circumferential direction of the rotating shaft, and that are arranged so as to be spaced in a rotational axis direction parallel to the axis of the rotating shaft; and a differential mechanism that is provided between a pair of rotors lying adjacent to each other in the rotational axis direction, and that combines the rotational force from each of the pair of rotors and transmits the rotational force to the rotating shaft.

A multirotor wind turbine (1) comprising a tower structure (2) and at least one load carrying structure (3, 4), each load carrying structure (3, 4) being arranged for carrying two or more energy generating units (5, 7) comprising a rotor (6, 8). At least two of the rotors are upwind or downwind rotors (6), the energy generating units (5) comprising upwind or downwind rotors (6) being arranged with their centres of gravity at a first distance behind the tower structure (2) along a direction of the incoming wind, substantially at the same vertical level, and at opposite sides of the tower structure (2) at substantially the same second distance to the tower structure (2) along a direction substantially perpendicular to the direction of the incoming wind. The multirotor wind turbine (1) is self-yawing, even under turbulent wind conditions.

The invention relates to an improved, in particular simpler, lighter, mechanically more stable and operationally more reliable offshore wind power plant (100) that can float. By means of a cable (110) constructed as a combination of a power line that is held at least virtually without loading and a holding cable that absorbs all the mechanical forces that occur for holding the wind power plant on a single fixed-location anchoring point (111), said power plant can be connected to the anchoring point such that the power plant can move with six degrees of freedom. A coupling (112) is arranged at a single connecting point (118) between the cable and the wind power plant and, to make an electrical connection, is constructed with a sliding coupling and, for mechanical transmission of force, is constructed with a swivel coupling. The wind power plant has a supporting unit (101) constructed as a semi-submersible having ballast units (102) and buoyancy units (103), in particular a floating unit, and a supporting mast (104) which is firmly connected to the supporting unit and has a machine gondola (105) fixedly arranged on the latter and having at least one rotor (106) and at least one electric generator. The highest possible horizontal distance is formed between the connecting point and a substantially vertical plane of rotation of the rotor.