JPH04103883A - Wind mill - Google Patents

Abstract

PURPOSE:To carry out the load control by changing the cone angle of blades corresponding to the change of the wind energy, by connecting the extending end of a rotary shaft and the intermediate parts of the blades with elastic supporters furnishing a spring and a dash pot. CONSTITUTION:The first locking members 7 provided on the intermediate part of blades 6 and the second locking members 9 provided to a link receiver 8 are connected by elastic supporters 10 each of which furnishes a spring 11 and a dash pot 12. As a result, when the wind energy is increased, the elastic supporters 10 are contracted to function to increase the cone angle, and the blades 6 are rotated in a balanced position. Consequently, the wind receiving area can be changed according to the change of the wind energy, and a load control can be carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a wind turbine, and more particularly to a wind turbine that performs load control by changing the cone angle of its blades in accordance with wind speed.

Conventional technology Traditionally, the load control methods for wind turbines are: - Stall control method, which controls the load by releasing wind energy by stalling at high wind speeds; - Making the blade pitch angle variable, allowing wind energy to be released. There is a method using variable pitch control.

Problems to be Solved by the Invention However, the method of controlling the load on wind energy conversion equipment lies primarily in how to release the wind energy that enters the wind turbine, especially when gusts of wind are added at high wind speeds. Wind energy needs to escape.

However, in the conventional method described above, the response speed to changes in wind energy is slow, so there is a problem in that the blade is overloaded.

The present invention was made in order to solve the problems of the prior art, and an object of the present invention is to provide a wind turbine capable of load control by changing the cone angle of the blades according to changes in wind energy. .

Means for Solving the Problems In order to solve the above problems, the present invention includes a rotor head supported at the end of a nacelle via a rotating shaft, and a rotor head fixed to the rotor head extending in the axial direction of the rotor head. a link receiver; a plurality of support members fixed to the outer periphery of the rotor head;
a wing whose one end is engaged with each of these support members and whose other end is rotatably attached in the axial direction of the rotor head; a first locking member formed in the middle of the wing; and the link receiver. The wind turbine is equipped with an elastic support body having a spring and a dashpot, which connects the second locking member formed in the wind turbine.

Effect According to the above means, when the wind energy is small, the cone angle of the blade is small, but when the wind energy increases, the elastic support that connects the middle of the blade and the link receiver is compressed, and the cone angle is increased. and rotates in a balanced position.

EXAMPLE Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

A single figure shows a side view of a wind turbine according to this embodiment, and 1 is a tower having a predetermined height with its lower end fixed to the ground surface, etc., and a nacelle 2 is fixed to the upper end of this tower 1. . 3 is a generator placed inside this nacelle 2 (not shown)
It is the axis of rotation. A rotor head 4 is fixed to the end of the rotary shaft 3, and a plurality of support members 5 are fixed at equal intervals around the outer circumference of the rotor head.

Further, 6 is a blade having a predetermined pitch angle, and this blade 6
A first locking member 7 is formed in the middle of the blade 6, and the blade 6 is attached to the support member 5 by pin connection so as to be rotatable in the axial direction of the rotating shaft 3. Reference numeral 8 denotes a link receiver, one end of which is fixed to the rotor head 4, and a second lock support member 9 formed at the other end.

Furthermore, 10 is an elastic support body having a spring 11 and a dashpot 12 and supported at both ends by two link rods 13, one of which is connected to the first support member 7 and the other. are respectively engaged with the second support member 8, thereby connecting both support members 7 and 8.

In addition, the dashpot 12 means a mechanical speed governor,
It has an elastic restoring effect such as a suppressor.

In the above configuration, when the wind turbine rotates due to the wind from the direction of arrow H, the wind turbine rotates at the cone of the wind turbine blade 6 at a point where the centrifugal force acting on the blade 6 and the reaction force of the force exerted by the spring 11 + the dart pot 12 are balanced. The angle (θ) is maintained. The role of the elastic support body 10, which is a combination of the spring 11 and the dashpot 12, is to support the blade 6 when the rotor is stopped and to prevent hunting of the blade cone angle when the rotor is rotating.

Here, the number of wind turbine blades 6 is n, the mass of one blade is m1, the center of gravity position of the blade (position from the rotor center) is r1, and the rotational speed at the center of gravity position is V (V = (2πN/60) ・r).

However, N (rpm) is the rated rotation speed of the rotor), A1 is the swept area of one blade, A1 is the wind speed, v1 is the air density, and ρ is the air density.
If the cone angle at that time is θ, then the centrifugal force (F c) is F
c=mv”/r.

Since the wind force (Fw) is Fw=1/2 (pv'-A), the cone angle θ is determined by θ=Tan (Fw/Fc).

When the rotation reaches the rated rotation, the centrifugal force Fc becomes a constant value, and the cone angle θ is uniquely determined by the wind speed. In other words, when the wind speed is high, the cone angle increases and the blade 6
Load control can be performed to automatically reduce the wind blowing area and the load.

Effects of the Invention As described above, according to the present invention, a link receiver fixed to a rotor head, a wing rotatably attached to the outer periphery of the rotor head in the axial direction of the rotating shaft, and a link receiver fixed to the rotor head; An elastic support with a spring and a dashpot is provided that connects and engages the middle part of the wing with the link receiver, so when the wind energy is small, the cone angle of the wing is small, but when the wind energy is large, the link between the middle part of the wing and the link holder is provided. The elastic support that connects the receiver is compressed and acts to increase the cone angle.

As a result, the area of the wind receiving area can be changed according to changes in wind energy, and a wind turbine capable of load control can be realized.

[Brief explanation of the drawing]

The single figure is a side view of an example of a wind turbine according to the invention. 1... Tower, 2... Nacelle, 3... Rotating shaft, 4... Rotor head, 5... Support member, 6... Wing, 7... First locking member, 8... Link receiver, 9 ...Second locking member,
10...Elastic support body, 11...Spring, 12...Dashpot, 13...Link rod.

Claims (1)

[Claims] A rotor head supported at the end of the nacelle via a rotating shaft, a link receiver fixed to extend in the axial direction of the rotor head, and a plurality of support members fixed to the outer periphery of the rotor head; one end is engaged with each support member of the
a blade whose other end is rotatably attached in the axial direction of the rotor head; a first locking member formed in the middle of the blade; and a second locking member formed in the link receiver. A windmill characterized in that it comprises an elastic support having a spring and a dashpot that are connected to each other.