DRIVE SYSTEM FOR INTERIOR WIND TURBINES OF GREAT HEIGHTS AND PERFORMANCE

Abstract

The invention relates to a drive system for interior wind turbines, consisting of a rotatable tower (5) with a rotor mounted at hub height, the generator (16) being located at the foot of the tower (5) on a drive/generator platform (13) and the rotor torque being transferred from above downwards to the generator (16). Particular requirements are placed on such a drive system as the height of the interior wind turbine increases. A steel-wire-cable-reinforced flat belt (18) is used as a transfer element, the ends of which are joined in a particular way to form an endless belt the pretensioning of which is regulated dependent on the properties of the wind, and automatic monitoring is provided which executes an immediate controlled shut-down of the drive system if damage occurs.

Claims

1. A drive system for an onshore wind power installation of great heights and outputs, composed of a rotatable tower (5) having a rotor (3) mounted at a hub height (NH) and a drive and generator platform (13) disposed at the foot of the tower (5), characterized in that a flat belt (18) is provided for transmitting the rotor torque, said flat belt (18) enabling a reliable operation with good efficiency and a long service life, wherein as a transmission element in one or multiple parts, a flat belt (18) which is connected by loops, and by way of a large belt pulley (2) at the hub height (NH), and by way of guide rollers on the path to the small belt pulley (17) on the drive/generator platform (13), transmits and feeds the rotor torque singularly or while bifurcating through the drivetrain; the flat belt (18), by way of incorporated steel wire ropes of great strength, thickness and number, is available as a high-tensile flat belt (18) also in double the length of the spacing of the upper belt pulley (2) from the lower belt pulley (17); the high-tensile flat belt (18) by way of wire rope combinations and connections, while interacting with the material of the vulcanization, is suitable for forming a loop at any arbitrary location in the flat belt (18) as well as at every location in the belt arrangement in the rotatable tower (5); in addition to the permanent pre-tensioning of the flat belt (18) from the floating dead weight of the drive/generator platform (13), an optimal position of the pre-tensioning weights (20) by means of CMS is provided for the fine adjustment to the currently prevailing wind conditions; proven method procedures with a long-term effect on the coefficient of friction p are used for guaranteeing the reliable transmission of torque between the belt pulleys (2) and (17) and the flat belt (18); and automatic monitoring for permanently checking the integrity of the flat belts (18) is provided, said automatic monitoring performing the immediate controlled shut-down of the drive system in the event of damage.

Description

[0012] In the drawings:

[0013] FIG. 1 shows an onshore wind power installation which is suitable for utilizing the wind in tropospheric layers, in the embodiment having a rotatable tower and an expanded tower cross section;

[0014] FIG. 2 shows an onshore wind power installation which is suitable for utilizing the wind in tropospheric layers, in the embodiment having a rotatable tower as the vertical column, and at least two counter-bearing pressure columns;

[0015] FIG. 3 shows the upper region of the drive system for an onshore wind power installation as per FIG. 1 or 2; and

[0016] FIG. 4 shows the lower region of the drive system for an onshore wind power installation as per FIG. 1 or 2.

[0017] The onshore wind power installation as per FIG. 1 is conceived for utilizing high altitude wind. Said onshore wind power installation in principle is composed of a rotatable tower 5 having an expanded tower cross section 4, the rotor 3 with the rotor hub and the rotor shaft 1, as well as the drive and generator platform 13. A wind power installation of this configuration is known from publication DE 20 2017 003 631 U1. The use of large tubes finally rolled (to up to 3 m in diameter) for the tower 5 in a dual or multiple arrangement in the direction of the primary axis of the tower, and having a downward increase in terms of expansion in the direction of higher load, installed on a rotary connection 6 known and proven in the sector of large excavators, in association with a furthermore increased hub height (NH) in the range from 160 m (lower dashed line) to 200 m (upper dashed line), overall permits a more favorable dead weight and lower costs, despite a higher input of energy in comparison to the conventional construction of the tower 5 having a flexurally stressed cross section.

[0018] The onshore wind power installation having the rotatable tower 5 and the expanded tower cross section 4, by way of the primary axis of the tower enables the use of the new drive system for transmitting the rotor torque to the drive/generator platform 13 in the rotatable tower foot. The upper limit of the Prandtl layer is plotted in the drawing, denoted by the reference sign 15. An onboard hoist 14 as an auxiliary means for carrying out the vertical rotor blade assembly, service work and repair work is disposed on the tower 5.

[0019] An onshore wind power installation illustrated as per FIG. 2 is known as a “Turning Tower” from publication DE 10 2016 014 799 B4. The upper image shows the installation in a lateral view; the plan view is reproduced in the lower image. The onshore wind power installation is composed of a rotatable tower 5 having a vertical column 7, and having at least two counter-bearing, horizontally and vertically expanded pressure columns 8. The finally rolled large tubes in the manufactured length for the columns 7, 8, and finally rolled or edge-bent profiles are joined to form tower sections. These profiles are erected and joined vertically, section-on-section according to new technological methods, without the use of large lifting gear, or erected as a completely equipped tower 5 assembled horizontally on the ground.

[0020] The horizontal expansion angle 9 and the vertical expansion angle 10 are illustrated in the drawing. The machine room 12 as well as the drive/generator platform 13 are situated on a support structure at the foot of the wind power installation. In the case of the smaller embodiment of the tower construction, the hub height (NH) is 200 m (lower chain-dotted line), whereas the hub height (NH) of the larger embodiment of the tower construction is 300 m (upper chain-dotted line). In this way, the higher wind speeds arising in this region are utilized.

[0021] The turning circle 11 for the structural stability of the onshore wind power installation is shown in the plan view as per FIG. 2.

[0022] The drive system for transmitting the rotor torque from the height of the rotor hub 1, including the gearing and/or drivetrain bifurcation for converting the torque so as to be adapted to the rotating speed of the generator 16 in the rotatable towers 5 of the two onshore wind power installations is illustrated in the drawings as per FIG. 3 (upper region) and FIG. 4 (lower region). The force transmission element between the two belt pulleys 2 and 17 is a flat belt 18. The latter is internally reinforced by a plurality of high-tensile steel wire ropes that are disposed so as to be mutually parallel and are disposed in the traction layer between the running layer and the cover layer. Using this steel-wire-rope-reinforced, loop-forming flat belt 18, an intentional gearing ratio is integrated as a result of the dissimilar diameters of the upper and the lower belt pulley 2 and 17, respectively.

[0023] The drawings as per FIG. 3 and FIG. 4 show the fundamental construction of a drive with a bifurcated drivetrain in the rotatable tower 5, having a bifurcation to two generators 16. Two flat belts 18 from the upper large belt pulley 2, by way of guide rollers that are assembled in parallel at all times, are guided downward through the tower 5 to two belt pulleys 17. Each of the two associated generators 16 is on the drive/generator platform 13 and, as a result of the dead mass thereof, generates the majority of the belt pre-tensioning.

[0024] In addition, the linkage 21 having the pre-tensioning weight 20 has the possibility of closed-loop controlling the pre-tensioning as a function of the wind speed. A drivetrain bifurcation having two generators 16 is illustrated in FIG. 4. Such an embodiment is not mandatory, however. The transmission of force from the top to the bottom can also take place by one flat belt 18 to one generator 16. As a result of the primary axis of the rotatable tower—proceeding from the rotatability on the ground by way of the drive in the rotatable tower foot and the steel-wire-rope-supported, loop-forming flat belt drive with the bifurcated drivetrain, including the gearing ratio between the rotor shaft 1 and the shaft of the generator 16—a reliable permanent operation is guaranteed at any arbitrary hub height.

[0025] The flat belt 18 is routed downward in the interior of the vertical column and in this way is protected in relation to external influences (influences of rain or dust, etc.) and in relation to damage to the drive system.

LIST OF REFERENCE SIGNS

[0026] 1 Rotor hub with rotor shaft

[0027] 2 Belt pulley

[0028] 3 Rotor

[0029] 4 Expanded tower cross section

[0030] 5 Rotatable tower

[0031] 6 Rotary connection

[0032] 7 Vertical column

[0033] 8 Pressure column

[0034] 9 Horizontal expansion angle

[0035] 10 Vertical expansion angle

[0036] 11 Turning circle

[0037] 12 Machine room/operations

[0038] 13 Drive/generator platform

[0039] 14 Onboard hoist

[0040] 15 Upper limit of the Prandtl layer

[0041] 16 Generator

[0042] 17 Belt pulley

[0043] 18 Flat belt

[0044] 20 Pre-tensioning weight

[0045] 21 Linkage

[0046] NH Hub height