Blade pitch-angle control apparatus and wind turbine generator

Abstract

A blade pitch-angle control apparatus is provided which can reduce the number of machining processes required for manufacturing a hub and which improves the maintainability due to a reduction in weight of each of hydraulic cylinders. The blade pitch-angle control apparatus, which is used in a wind turbine generator having a plurality of blades and which individually operates the pitch angle of each of the blades, uses the two hydraulic cylinders to operate each of the blades.

Description

RELATED APPLICATIONS[0001]The present application is based on, and claims priority from, International Application Number PCT / JP2008 / 060585, filed Jun. 10, 2008, the disclosure of which is hereby incorporated by reference herein in its entirety.TECHNICAL FIELD[0002]The present invention relates to wind turbine generators, and more particularly, to a blade pitch-angle control apparatus that controls a blade pitch angle in a wind turbine.BACKGROUND ART[0003]In conventional techniques, propeller-type wind turbines used in wind turbine generators rotate when a plurality of blades (wind-turbine blades) attached to a rotor head receive wind. The rotation of the rotor head is increased in speed by a speed-increasing gearbox connected to the rotary shaft and then drives a generator to generate electricity.[0004]In those wind turbine generators, the blade pitch angle of each blade is individually adjusted so as to obtain a predetermined rotating speed and output power depending on the wind c...

AI Technical Summary

Benefits of technology

[0010]On the other hand, for example, a spindle is attached at an arbitrary point P located at a predetermined position on a blade-side end face 5a which is supported so as to be pivotable relative to the hub 06. The tip of a piston rod 42 that is extended and contracted by hydraulic pressure is connected to the spindle at the point P, so that the point P pivots within a range of about 90 degrees (between PA and PB) with the center point “o” of the blade-side end face 5a serving as the center, in response to the extension and contraction of the piston rod 42. Therefore, the blade pivoting together with the blade-side end face 5a revolves in a desired direction to change the pitch angle, thereby allowing the pitch angle to be controlled.

[0012]Accordingly, the entire length of the hydraulic cylinder 41 is increased, and the hydraulic cylinder 41 is attached to the hub 06, to which the blade and the pitch-angle control apparatus are attached, as if the hydraulic cylinder 41 penetrated through the hub 06. Not only does the shape of the hub 06 become complicated, but also a trunnion bracket for attaching the hydraulic cylinder 41 needs to have a complicated structure.

[0014]The present invention has been made in view of those circumstances, and an object of the present invention is to provide a blade pitch-angle control apparatus and a wind turbine generator capable of reducing the number of machining processes required to manufacture a hub and of improving the maintainability by reducing the weight of a hydraulic cylinder itself.

[0017]According to this blade pitch-angle control apparatus, two cylinders are used to operate each of the blades, so that a desired pitch-angle control range can be ensured by using the cylinders, which have short strokes and are lightweight.

[0021]According to this wind turbine generator, the blade pitch-angle control apparatus, which individually operates a pitch angle of each of the blades, is included. Therefore, it is possible to use two cylinders which have short strokes and are lightweight to operate each of the blades and to ensure a desired pitch-angle control range for the blade.

[0022]According to the present invention, it is possible to provide a blade pitch-angle control apparatus and a wind turbine generator capable of reducing the number of machining processes required to manufacture a hub constituting a rotor head and of improving the maintainability by reducing the weight of a cylinder itself.

Problems solved by technology

Not only does the shape of the hub 06 become complicated, but also a trunnion bracket for attaching the hydraulic cylinder 41 needs to have a complicated structure.

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