JPS5920871B2 - windmill - Google Patents

Description

[Detailed description of the invention] This invention relates to a windmill.

The practical application of wind turbines for extracting wind energy from natural wind is being promoted due to the need to develop alternative energy to oil.

One of the problems in putting wind turbines into practical use is widening the range of rated output operation and avoiding damage to the wind turbine during gusts.

The power P of the windmill is ρ: air density, U, x: wind speed,
If η: efficiency and A: swept area, then it is given by:

When generating electricity using a power generation device using a wind turbine and feeding the generated power to a power grid, the wind turbine is often required to operate at its rated output in order to maintain the quality of the grid power.

As shown in Fig. 1, an example of such an operation mode is that the starting rotation is performed at a wind speed of U1 or more, but the output is not connected to the grid power grid until the rated wind speed UR is reached to obtain the rated output pR.
A constant output is supplied only between wind speeds UR and U2.

However, in Japan, the average wind speed is relatively low, and the range of wind speeds necessary for rated output operation is narrow. However, as is clear from equation (1), if the wind turbine's receiving area is increased, the rated output can be increased. This means that the wind speed required to obtain the wind speed does not need to be small, and even low-density wind power can be used effectively, which is extremely advantageous for the use of wind energy in regions with climates where the average wind speed is low. .

For this reason, a wind turbine that can increase the area of the wind turbine that receives wind is desired.

On the other hand, when gusts of wind blow, such as during a typhoon, the gusts can hit windmills and cause accidents that damage them.
Countermeasures are necessary.

One of the effective countermeasures is to reduce the wind turbine area only during typhoons.

Thus, there is a desire for a wind turbine that can adjust the size of the wind blowing area as necessary, but to date, no wind turbine has been found that easily and reliably satisfies this requirement.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wind turbine whose wind receiving area can be easily and reliably adjusted as required.

In response to this purpose, the windmill of the present invention is a windmill equipped with one or more blades, and the windmill area of the entire windmill is made variable by making the windmill area of the blades variable. It is characterized by

The details of this invention will be explained below with reference to the drawings showing one embodiment.

In FIGS. 2, 3, and 4, reference numeral 1 denotes a wind turbine device, and the wind turbine device 1 includes a wind turbine 3 having a horizontal rotation axis on the top of a tower 2.

The windmill 3 has two blades 4a and 4b.

The blades 4a and 4b each include a first blade member 5 and a second blade member 6 located in the direction of the radius vector R, and the second plate member 6 is movable with respect to the first blade member 5. Relative displacement is possible in the radial direction.

The first blade member 5FL is a sheath-like hollow body, the base end 7 of which is closed, and the distal end 8 of which is open.

The outer peripheral shape of the cross section of the first blade member 5 is similar to that of a normal blade.

A base end portion 1 of the first blade member 5 is fixed to a rotating shaft via a mounting rod 9.

The outer circumferential shape of the cross section of the second blade member 6 is the same as that of a normal blade, and it is housed within the first blade member 5 and can move forward and backward from the first blade member 5 in the radial direction. be.

A plurality of rollers 10 are arranged between the first blade member 5 and the second blade member 6 to smooth relative displacement between the two.

In order to relatively displace the first blade member 5 and the second blade member 6, a drive device 11 is provided between them.

That is, the drive device 11 includes a motor 12, a screw shaft 13, and a nut 14.

The motor 12 is fixed inside near the base end 7 of the first blade member 5, and this screw shaft 13 is connected to the output shaft of the motor 12, and the screw shaft 13 is connected to the output shaft of the motor 12, and
and located inside the second blade member 6.

A nut 14 is attached to the inside of the second blade member 6, and the screw shaft 13 is fitted into this nut 14.

Therefore, by rotating the motor 12 in the forward or reverse direction, the screw shaft 1 that is fitted with the nut 14 is rotated.
3 rotates forward or reverse, the second blade member moves in and out of the first blade member 5, and eventually the blade 4 a
, 4 b changes the affected area.

The wind turbine configured in this manner has blades 4a and 4b of &ζ variable length, and by moving the second blade member 6 forward and backward with respect to the first blade member 5, the diameter of the wind turbine and, therefore, the wind The area can be adjusted and the wind turbine output can be controlled as required. For example, during typhoons and strong winds, the diameter of the wind turbine can be minimized to reduce the wind pressure on the blades and prevent damage to the wind turbine. can do.

Furthermore, when the wind speed is low, the diameter of the wind turbine is set to be the longest, so that wind energy can be effectively extracted.

Furthermore, the length of the blades can be adjusted according to the state of the load system, and power can be sent as needed, increasing the degree of freedom in control.

By the way, the installation angle of the ψ blade, the circumferential speed of the α blade,
If r is the radius vector of two blades, and the angular velocity of two blades is expressed by Regarding advancing and retreating the blade member 6,
It is desirable not only to simply provide linear displacement in the radial direction, but also to provide rotational displacement (twisting) around the radius vector.

In this case, the first blade member 5 and the second blade member 6 are formed as follows.

As shown in FIG. 5, where R1 is the outer diameter of the first blade member 5, and X is the protrusion amount of the second blade member, r-R1+x, in the range of r>R1, V>U. , jan (ψ
+α)2ψ+α, so if r=R1 and ψ=91, then if r=R1+x, it can be approximated by in the range of X < Rt.

From this, when r>R1, it may be assumed that the rate of change in the angle of blade attachment is constant in the radial direction.

Therefore, the following transformation holds.

In other words, in the range r>R1, if the torsion of the groove in the guide surface of the first plate attachment 3 material 5 and the torsion in the external shape of the second blade member 6 are given so as to satisfy equation (2'), the blade By attaching the blade in the length direction (radial direction), it is possible to precisely control the radius vector and the swept area, taking into consideration the change in the angle Q.

Although the above description has been made regarding an embodiment in which the present invention is applied to a propeller type wind turbine, the present invention can be applied as is to other types of wind turbines.

FIG. 6 shows an embodiment in which the present invention is applied to a gyro mill type wind turbine device.

The gyro mill type wind turbine device 21 has blades 24a, 2 through a stem 27 around a vertically located wind turbine rotating shaft 22.
4b is obsessed.

Blade 24a in this case. 24b also includes a hollow first blade member 25 and a second blade member 26 disposed within the hollow first blade member 25 so as to be relatively displaceable.

As a drive device for driving the second blade member 26, the same drive device as the drive device 11 described above can be used.

As is clear from the above explanation, according to the present invention, the area of the wind receiving area can be easily and reliably adjusted as necessary, and therefore, it is possible to effectively utilize wind energy when the wind speed is low. Furthermore, it is possible to obtain a wind turbine with safety measures taken during typhoons and strong winds.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the operation mode of the wind turbine for power generation, Fig. 2 is a front view of the wind turbine device, Fig. 3 is a perspective view of the blades, and Fig. 4 is a partial sectional view of the IV-IV section in Fig. 3. FIG. 5 is a front explanatory view of the blades, and FIG. 6 is a perspective view of another wind turbine device. 1... Propeller type windmill device, 3... Windmill, 4a. 4b...Blade, 5...First blade member, 6...Second blade member material, 11
... Drive device, 13 ... Screw shaft, 21 ... Gyro mill type wind turbine device, 2
4 a, 24 b...Blade, 25...
...First blade member material, 26...Second blade member.

Claims (1)

[Scope of Claims] 1. A windmill comprising one or more blades, characterized in that the area of the wind turbine as a whole is made variable by making the area of the blades variable. 2. The plate 1 is characterized in that it includes at least a first blade member and a second blade member that can be stored in the first blade member and can move in and out of the first blade member. A wind turbine according to claim 1. 3. The windmill according to claim 1 or 2, wherein the windmill is a propeller type windmill. 4. The wind turbine according to claim 1, 2 or 3, wherein the second blade member is moved back and forth along a twist angle of the blade. 5. The windmill according to claim 1 or 2, wherein the windmill is a gyro mill type windmill.