JPH0343469B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to an energy conversion system that converts mechanical rotational energy converted from wind power by a wind turbine into energy such as electricity or heat. This invention relates to a wind turbine power transmission mechanism suitable for use in wind turbines.

[Prior Art] In conventionally known horizontal axis wind power generation systems, the wind turbine rotor, speed increaser, generator, etc. connected to the wind turbine blades are generally mounted horizontally in a nacelle attached to the top of the tower. are arranged and interconnected. However, in such a configuration, since the loaded weight of the upper part of the tower is large, it is necessary to increase the rigidity of the tower itself, and accordingly, the weight of the material forming the tower also increases. Therefore, the manufacturing cost of the system is relatively high.

In order to solve this problem, as shown in FIG. A wind turbine that transmits power to a rotating shaft 6 of
Already known.

However, in such a wind turbine, a yaw moment due to the meshing of the pair of bevel gears acts on the rotating shaft 3 of the wind turbine blade 2, and therefore,
Normally, the above-mentioned additional yaw moment is avoided by offsetting the rotation axis 3 of the wind turbine from the center of the tower, but in this case, there is a problem of instability because it is not mechanically balanced. .

[Problems to be Solved by the Invention] A technical problem to be solved by the present invention is to reduce the required rigidity and weight of the tower by reducing the loading weight of nacelles, etc. in the upper part of the tower, thereby improving the economic efficiency of the system. In the above-mentioned windmill with
Provides a mechanism that uses simple means to suppress the additional yaw moment associated with power transmission while simultaneously transmitting the required accelerating output to the output shaft, thereby maintaining a stable operating state of the system. An object of the present invention is to obtain a power transmission mechanism for a wind turbine.

[Means for Solving the Problems] In order to solve the above problems, the power transmission mechanism for a wind turbine of the present invention includes a housing that is rotatable around a vertical axis at the upper end of a tower, and a rotating shaft of a wind turbine blade is horizontally supported. Then, two bevel gears are meshed with the bevel gear attached to the rotating shaft at opposing positions, and the differential shafts attached to these two bevel gears are made to hang down along the tower, and a bevel gear is attached to their lower end. , is configured by connecting a differential planetary speed increasing mechanism that rotates with each rotational axis directed in the vertical direction and transmits the differential rotational force of the differential shaft to one output shaft that rotates in one direction. Ru.

[Function] In the power transmission mechanism for a wind turbine having the above configuration, rotational forces in different directions are transmitted to the differential shaft in two parts through the bevel gear on the rotating shaft of the wind turbine blade and the two bevel gears meshing with the bevel gear. These rotational forces are collected on one output shaft in the differential planetary speed increasing mechanism, and loads such as generators and heat generating equipment are driven.

In particular, in the differential planetary speed increase mechanism connected to the lower end of the differential shaft, the rotational speed of the differential shaft is increased to an appropriate speed, and at the same time, the torque of the output shaft is reduced due to the speed increase. As a result, the deflection yaw moment acting between the housing and the tower can be suppressed to a sufficiently small level, and due to the mechanism of the differential planetary speed increase mechanism, there is no other effect on the yaw moment, and fluctuations in wind direction can be suppressed. The stable operating state of the system is maintained while arbitrarily tracking the direction of yaw.

[Embodiment] FIG. 1 shows a first embodiment of a wind turbine equipped with a power transmission mechanism according to the present invention. In the wind turbine shown in the figure, a housing 12 is attached to the upper end of a tower 11 so as to be rotatable around a vertical axis by a yaw bearing 13, and a rotating shaft 16 of a wind turbine blade 15 is horizontally supported by the housing 12. Inside the housing 12, a bevel gear 17 is attached to the other end of the rotating shaft 16, and two bevel gears 19 and 20 that mesh with the bevel gear 17 simultaneously at the upper and lower end positions are vertically concentric with each other. It is attached to the upper end of the differential shafts 21 and 22 arranged in a shape. Both differential shafts 21 and 22 are connected to one differential shaft 2.
1 passes through the hollow differential shaft 22 of the other, and are arranged concentrically with each other, and the tower 1
The housing 12 is also arranged concentrically with the axis of rotation of the housing 12, which is rotatably mounted at the upper end of the housing 12 by a yaw bearing 13.

The differential shafts 21 and 22 are suspended along the tower 11, and a differential planetary speed increase mechanism 25 is connected to their lower ends, which rotates within the tower 11 with the rotation axis of each gear facing the vertical direction. are doing. This differential planetary speed increasing mechanism 25 is for transmitting the differential rotational force of the differential shafts 21 and 22 that rotate in different directions to one output shaft 27 that rotates in one direction. The rotational force of this output shaft 27 is connected to drive a load 28 such as a generator or heat generating equipment, and the load 28 has a control panel 29 for controlling it.
is connected.

In the differential planetary speed increasing mechanism 25 illustrated in the embodiment of FIG. 1, an internal gear 31 is fixed to the lower end of the differential shaft 22, and the internal gear a plurality of planetary gears 32 meshing with 31;
A sun gear 35 is connected to the output shaft 27, which supports rotating shafts 33 of .

The second embodiment shown in FIG. 2 shows a different configuration example of the differential planetary speed increasing mechanism 25, in which the differential shaft 2
An internal gear 41 is fixed to the lower end of the differential shaft 2.
1 supports rotating shafts 43 of a plurality of planetary gears 42, . A sun gear 45 is connected to the output shaft 27. Such a configuration is advantageous for adjusting the speed increase rate of the output shaft 27.

In a wind turbine having such a configuration, the bevel gear 17 and the bevel gears 19, 2 are connected from the rotating shaft 16 of the wind turbine blade 15 rotated by wind energy.
0, rotational forces in different directions are transmitted to the differential shafts 21 and 22 in two parts, and these rotational forces are collected in one output shaft 27 in the differential planetary speed increasing mechanism 25, and the generator, A load 28 such as a heat generating device is driven.

In the bevel gear train and the differential planetary speed increasing mechanism 25, the rotational speed can be increased, thereby maintaining high energy conversion efficiency. Further, as the speed increases, the torque of the output shaft 27 becomes smaller in accordance with the rate of speed increase compared to the rotation shaft 16 of the wind turbine blade 15. The torque acts as a deflection yaw moment between the housing 12 and the tower 11, but it can be suppressed to a sufficiently low level as described above. The yaw direction is arbitrarily tracked as the wind direction changes without affecting the moment, thereby simplifying yaw drive control and maintaining a stable operating state of the system.

[Effects of the Invention] According to the wind turbine power transmission mechanism of the present invention detailed above, in the above-mentioned wind turbine in which the load weight at the top of the tower is reduced, the additional yaw moment accompanying power transmission can be suppressed to a small level, A stable operating state of the system can be maintained.

In addition, since the rotation of the wind turbine blades is transmitted from the top of the tower through a pair of differential shafts, it is possible to transmit large torque at low speeds. The shaft allows for easy torque transmission over long distances.
Moreover, it is possible to provide a mechanism that can suppress the additional yaw moment to a small value by simple means and at the same time transmit the required speed-up output to the output shaft.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a first embodiment of a power transmission mechanism for a wind turbine according to the present invention, FIG. 2 is a sectional view of a main part of the second embodiment, and FIG. 3 is a configuration diagram of a conventional example. 11...Tower, 12...Housing, 15...
...Windmill blade, 16...Rotating shaft, 17, 19,
20...Bevel gear, 21, 22...Differential shaft, 25...
...Differential planetary speed increase mechanism, 27...Output shaft.

Claims (1)

[Claims] 1. A housing rotatable around a vertical axis at the upper end of the tower horizontally supports the rotating shaft of the wind turbine blade, and a bevel gear attached to the rotating shaft,
Two bevel gears are meshed at opposite positions, and the differential shafts attached to these two bevel gears are suspended along the tower, and each rotation axis is rotated vertically at the lower end of the differential shaft. A power transmission mechanism for a wind turbine, further comprising a differential planetary speed increasing mechanism that transmits the differential rotational force of the differential shaft to one output shaft rotating in one direction.