A WIND TURBINE

Abstract

A wind turbine (1) comprising a turbine rotor (3) with one or more blades, a generator (4) and a drive train (5) interconnecting the turbine rotor (3) and the generator (4). The drive train (5) is provided with a main gear (6) directly driven by the turbine rotor (3). A plurality of pinions engages the main gear (6). Each of the pinions drives a hydraulic pump (7). A hydro motor (8) is connected to the respective pumps (7) via respective high pressure (9) and low pressure lines. The hydro motor (8) engages an input shaft of the generator (4). A planetary gear transmission (10) is arranged between each pinion and the respective hydraulic pump (7).

Claims

1. A wind turbine comprising a turbine rotor with one or more blades, a generator, a drive train interconnecting the turbine rotor and the generator, wherein the drive train is provided with a main gear directly driven by the turbine rotor, a plurality of pinions engaging the main gear, a plurality of hydraulic pumps, each pump being driven by one of said pinions, at least one hydro motor connected to the respective pumps via respective high pressure and low pressure lines, the at least one hydro motor engaging an input shaft of the generator, characterized in that a planetary gear transmission is arranged between each pinion and the respective hydraulic pump.

2. A wind turbine according to claim 1, wherein the hydro motor has substantially the same capacity as each of the pumps.

3. A wind turbine, according to claim 1, wherein the pumps are located at opposite sides of the main gear.

4. A wind turbine according to claim 1, wherein the main gear is an external gear.

5. A wind turbine according to claim 1, wherein the pumps have substantially the same capacity.

6. A wind turbine according to claim 1, wherein the drive train has at least two hydro motors, which have substantially the same capacity.

7. A wind turbine according to claim 1 comprising an annular gear box encasing the main gear and supporting the planetary gear transmissions and the hydraulic pumps.

8. A wind turbine, according to claim 2, wherein the pumps are located at opposite sides of the main gear.

9. A wind turbine according to claim 2, wherein the main gear is an external gear.

10. A wind turbine according to claim 3, wherein the main gear is an external gear.

11. A wind turbine according to claim 2, wherein the pumps have substantially the same capacity.

12. A wind turbine according to claim 3, wherein the pumps have substantially the same capacity.

13. A wind turbine according to claim 4, wherein the pumps have substantially the same capacity.

14. A wind turbine according to claim 2, wherein the drive train has at least two hydro motors, which have substantially the same capacity.

15. A wind turbine according to claim 3, wherein the drive train has at least two hydro motors, which have substantially the same capacity.

16. A wind turbine according to claim 4, wherein the drive train has at least two hydro motors, which have substantially the same capacity.

17. A wind turbine according to claim 5, wherein the drive train has at least two hydro motors, which have substantially the same capacity.

18. A wind turbine according to claim 2 comprising an annular gear box encasing the main gear and supporting the planetary gear transmissions and the hydraulic pumps.

19. A wind turbine according to claim 3 comprising an annular gear box encasing the main gear and supporting the planetary gear transmissions and the hydraulic pumps.

20. A wind turbine according to claim 4 comprising an annular gear box encasing the main gear and supporting the planetary gear transmissions and the hydraulic pumps.

Description

[0014] The invention will hereafter be elucidated with reference to very schematic drawings showing embodiments of the invention by way of example.

[0015] FIG. 1 is a perspective view of a part of an embodiment of the wind turbine according to the invention.

[0016] FIG. 2 is a similar view as FIG. 1 of a part of the embodiment of FIG. 1 on a larger scale.

[0017] FIG. 3 is a similar view as FIG. 2, but showing an alternative embodiment.

[0018] FIG. 4 shows a cross section of the main gear with pumps.

[0019] FIG. 1 shows a part of an embodiment of a wind turbine 1 according to the invention. The wind turbine 1 has a nacelle 2 mounted on a tower (not shown). The wind turbine 1 comprises a turbine rotor 3 with three blades (not shown) and two generators 4 which are mounted inside the nacelle 2. The generators 4 are suitable for transferring power generated by the blades 3 into electricity and rotate with a maximum rotation speed of 1500 revolutions per minute, for example, so that the dimensions of the generators 4 are limited. The turbine rotor 3 rotates at a much lower speed, for example 10 revolutions per minute.

[0020] A drive train 5 interconnects the turbine rotor 3 and the generators 4. The drive train 5 is provided with an annular gear box 6 which encases an external gear 6A (see FIG. 4). The main gear is directly driven by the turbine rotor 3. Six pinions 7A (FIG. 4) engage the main gear 6A.

[0021] FIG. 2 shows the drive train 5 at a larger scale. The drive train 5 comprises six hydraulic pumps 7 and two hydro motors 8. Each pump 7 is driven by one of the pinions and each hydro motor 8 is connected to three pumps 7 via respective high pressure lines 9 and low pressure lines (not shown). Each of the hydro motors 8 engage an input shaft of the respective generators 4 for driving the respective generators 4.

[0022] Between each pinion and the cooperating hydraulic pump 7 a planetary gear transmission 10 is arranged. This means that a mechanical transmission through two gear transmission stages is applied.

[0023] FIG. 3 shows a part of an alternative embodiment of the wind turbine 1. In this case the drive train 5 comprises 16 pumps 7, of which eight pumps 7 are located at a front side of the main gear 6 and eight pumps 7 are located at a rear side of the main gear 6. Furthermore, the drive train 5 of this embodiment comprises two double hydro motors 8, in which the shafts of two similar hydro motors are coupled to each other. The pumps 7 at the front side are connected to one of the double hydro motors 8, whereas the pumps 7 at the rear side are connected to the other double hydro motors 8.

[0024] In the embodiments as shown the respective pumps 7 and the respective motors 8 are similar, such that wind turbines with varying power capacities can be built in a modular way by varying the number of pumps 7, motors 8 and generators 4 without changing the dimensions of the turbine rotor 3 and main gear 6.