CN111520444A - Compact semi-direct-drive wind generating set gear box multi-branch power split transmission structure - Google Patents

Abstract

The invention discloses a multi-branch power split transmission structure of a gearbox for a compact semi-direct drive wind turbine generator set, comprising a three-stage planetary gear transmission system, the first-stage planetary gear transmission system is a fixed-shaft internal meshing transmission, and the power is transmitted by the third-stage planetary gear transmission system. The first-stage ring gear is input, and then multiple first-stage external gears form multiple branch outputs; the second-stage planetary gear transmission system is a fixed-shaft external meshing transmission, and the power is input by its multiple second-stage large gears. Then it is output through its multiple second-stage pinions; the third-stage planetary gear transmission system is a fixed-shaft external meshing transmission, and the power is input by its multiple third-stage large gears and collected to the third-stage central pinion for output. The invention can make full use of the radial space of the original second-stage planetary transmission, compared with the traditional compact semi-direct drive structure, under the premise of keeping the space unchanged, the bearing capacity of the gearbox transmission is comprehensively enhanced, and the transmission power is improved.

Description

Multi-branch power split transmission structure of compact semi-direct drive wind turbine gearbox

technical field

The invention relates to the technical field of gearbox transmission of wind turbines, in particular to a multi-branch power split transmission structure of a gearbox of a compact semi-direct drive wind turbine.

Background technique

Figure 1 is a schematic structural diagram of a traditional compact semi-direct drive wind turbine gearbox, which consists of a two-stage NGW type planetary gear transmission system with a total speed ratio between 22-25. The first-stage planetary gear transmission system 03 has a transmission ratio of about 4.5, the second-stage gear planetary transmission system 09 has a transmission ratio of about 5.5; the hub 04 is connected with the planet carrier 05 of the first-stage planetary gear transmission system and the inner ring of the main shaft bearing 06 together; the outer ring of the main shaft bearing 06 is connected with the box 07 and the generator casing 08 to form the outermost structure of the wind turbine, replacing the nacelle of the traditional structure; the planet carrier 010 of the second stage planetary gear transmission system and the first stage The sun gear 01 of the planetary gear transmission system is connected by the spline 02, the power from the blades is transmitted to the inside of the gearbox through the hub 04, and finally the sun gear 011 of the second-stage planetary gear transmission system is output to the generator;

On the existing platform, on the premise that the radial and axial dimensions of the transmission device are not changed, the model of the main bearing is unchanged and the power can be increased, the power of the wind turbine should be increased without changing the current status of the gearbox. For some structures, it is necessary to increase the radial size of each stage of the planetary transmission. Although the two-stage planetary transmission has sufficient room for development in the radial space, the first-stage planetary transmission is limited by the inner diameter of the main bearing. Therefore, the carrying capacity of the one-stage planetary transmission becomes a shortcoming for increasing power.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies and shortcomings of the prior art. In view of the problem that the increase of generator power is limited in the traditional NGW planetary transmission gearbox, a compact semi-direct drive wind turbine gearbox multi-branch power split transmission structure is proposed. , Under a certain space size of the gearbox, the power of the transmission can be increased, and the power generation can be increased, so that the power of the wind turbine can be applied between 2.5MW and 15MW.

In order to achieve the above purpose, the technical solution provided by the present invention is: a compact semi-direct drive wind turbine gearbox multi-branch power split transmission structure, including a first-stage planetary gear transmission system, a second-stage planetary gear transmission system and a third-stage planetary gear transmission system. First-stage planetary gear transmission system; the first-stage planetary gear transmission system is a fixed-shaft internal meshing transmission system, and the power is input from its first-stage inner gear ring, and then forms multiple branch outputs through its multiple first-stage external gears , the plurality of first-stage external gears are evenly distributed in the first-stage internal gear, and mesh with the first-stage internal gear respectively to distribute power evenly. The first-stage internal gear is connected to the hub of the wind turbine. Fixed connection, in which a first-stage external gear is installed on the cantilever end of a transmission shaft, which is the first transmission shaft and is supported on the gear box body and the bearing seat plate through the first bearing and the second bearing respectively. , the bearing seat plate and the gear box are fixed as a whole; the second-stage planetary gear transmission system is a fixed-shaft external meshing transmission system, and the output power of the first-stage planetary gear transmission system is generated by the second-stage planetary gear transmission system. The multiple second-stage large gears are input, and then output through its multiple second-stage pinions. The second-stage large gears are respectively meshed with their adjacent second-stage pinions to form a shunt. The multiple second-stage pinions The large gear and a plurality of second-stage pinions are evenly distributed around the center of the gearbox, and one of the second-stage large gears is mounted on the first transmission shaft and located between the first and second bearings, and one of the second-stage large gears The pinion is mounted on the cantilever end of another transmission shaft, the transmission shaft is the second transmission shaft, and is supported on the bearing seat plate through the third bearing, and both ends of the second transmission shaft are cantilever ends; the The third-stage planetary gear transmission system is a fixed-shaft external meshing transmission system. The power output by the second-stage planetary gear transmission system is input by a plurality of third-stage large gears of the third-stage planetary gear transmission system, and then passes through its third-stage center. The pinion is output to the generator of the wind turbine, the plurality of third-stage large gears are evenly meshed around the third-stage central pinion, and one of the third-stage large gears is mounted on the other cantilever end of the second transmission shaft, The third-stage central pinion is located in the center of the gearbox and is connected to the generator.

Further, the cantilevered end of the second transmission shaft on which the third-stage bull gear is mounted extends into the casing of the generator, so that the third-grade bull gear and the third-stage central pinion are located in the casing of the generator.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The original first-stage NGW planetary transmission of the traditional compact semi-direct drive wind turbine gearbox: the planetary transmission is divided into the internal meshing of the planetary gear and the ring gear and the external meshing of the planetary gear and the sun gear. In the principle of NGW transmission , the load-carrying capacity of the internal meshing is about 2.3 times that of the external meshing (based on the commonly used speed ratio and considering the different influences of the commonly used internal and external meshing gear materials), and the external meshing sun gear and/or externally meshing The carrying capacity of the planetary gear is The weak link of the planetary transmission (especially the external meshing sun gear), at the same time, due to the bidirectional meshing of the planetary gear teeth, the bending bearing capacity of the planetary gear is reduced by 30%.

Based on this, the present invention removes the sun gear from the first-stage transmission system, and fixes the planetary carrier at the same time. At this time, the planetary transmission is changed to the internal meshing of the fixed-axis transmission, and the planetary gear (ie, the first-stage external gear of the transmission structure) is the It becomes a one-way meshing, and then the inner gear and the hub are connected to become the input part, and the planetary gear becomes the output part. In this way, the carrying capacity of the transmission is comprehensively enhanced, and it is possible to increase the power. Under the condition of satisfying the strength, the width and number of teeth of the planetary gear can be reduced, and the first-stage transmission ratio can be increased.

2. Since the first stage of the transmission structure is a fixed shaft internal meshing transmission, the speed increase ratio is smaller than the original NGW planetary transmission under the condition of satisfying the gear strength. If the gear box is made into 2 stages of transmission, the total transmission speed of the gears It is relatively small, so one more gear transmission is made, so that the gearbox has a total of 3 gear transmissions to achieve the required total transmission ratio. The latter two stages are fixed-shaft external meshing transmission, and the power is finally collected on the third-stage central pinion, which is directly connected to the generator, so that the power of the transmission is improved on the premise of keeping the space unchanged. , so that the power of the wind turbine can be applied between 2.5MW and 15MW.

3. The design of the present invention makes full use of the radial space of the original second-stage planetary transmission of the traditional compact semi-direct drive wind turbine gearbox, and designs a 3-stage parallel shaft transmission structure (including 1-stage internal meshing and 2-stage external meshing). ), each stage contains multiplexing. Selecting the appropriate speed ratio matching and structural type from the gear strength and space achieves the purpose of increasing the power and keeping the total transmission ratio unchanged in the original space, providing a new transmission type for the design of the transmission gearbox for wind power generation. The above transmission route forms a multi-branch power split transmission structure.

Description of drawings

Figure 1 is a schematic structural diagram of a traditional compact semi-direct drive wind turbine gearbox.

FIG. 2 is a schematic diagram of the multi-branch power split transmission structure of the gearbox of the compact semi-direct drive wind turbine according to the present invention.

FIG. 3 is a schematic diagram of the spatial arrangement structure of the first-stage gear transmission system.

Figure 4 is a schematic diagram of the spatial arrangement of the second-stage gear transmission system.

Figure 5 is a schematic diagram of the spatial arrangement of the third stage gear transmission system.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments.

Referring to FIG. 2 , the multi-branch power split transmission structure of the compact semi-direct drive wind turbine gearbox provided in this embodiment includes a first-stage planetary gear transmission system, a second-stage planetary gear transmission system and a third-stage planetary gear transmission system. gear transmission system.

The first-stage planetary gear transmission system is a fixed-shaft internal meshing transmission system. The power is input by its first-stage inner gear 1, and then a first-stage external gear 2 forms a branch output, a=3 ,4,5..., the a first-stage external gears 2 are evenly distributed in the first-stage ring gear 1, and mesh with the first-stage ring gear 1 respectively to distribute power evenly. The stage ring gear 1 is connected with the hub 11 of the wind turbine by bolts, and a first stage external gear 2 is mounted on the cantilever end of a drive shaft 10, which is the first drive shaft and passes through the first drive shaft 10. The bearing 9 and the second bearing 13 are respectively supported on the gear box body 12 and the bearing seat plate 14 , and the bearing seat plate 14 and the gear box body 12 are fixed as a whole.

The spatial arrangement structure of the first-stage planetary gear transmission system is shown in Figure 3 (taking a=3 as an example), the serial number 1 is the ring gear; the serial numbers 2-1, 2-2, 2-3 are the three first stages The external gear, which is evenly distributed in the first-stage ring gear 1, meshes with the first-stage ring gear 1 respectively, and the power is evenly distributed in these three paths. The serial numbers 3-1, 3-2, and 3-3 indicated by dotted lines are three second-stage large gears, which are located on the same transmission shaft 10 as the first-stage external gear 2 .

The second-stage planetary gear transmission system is a fixed-shaft external meshing transmission system, and the output power of the first-stage planetary gear transmission system is input by b second-stage large gears 3 of the second-stage planetary gear transmission system, and then passes through the second-stage large gears 3 of the second-stage planetary gear transmission system. The c second-stage pinions 4 are output, and the second-stage large gears 3 are respectively meshed with their adjacent second-stage pinions 4 to form a split flow. The b second-stage large gears 3 and c second-stage small gears The gears 4 are evenly distributed around the center of the gearbox, and one of the second-stage large gears 3 is mounted on the first transmission shaft, and is located between the first bearing 9 and the second bearing 13, and one of the second-stage pinions 4 is mounted on. On the cantilever end of the other transmission shaft 8, the transmission shaft 8 is the second transmission shaft, and is supported on the bearing seat plate 14 through the third bearing 7, and both ends of the second transmission shaft are cantilever ends.

The spatial arrangement of the second-stage planetary gear transmission system is shown in Figure 4 (taking b=3 and c=3 as an example), and the serial numbers 3-1, 3-2, and 3-3 are three second-stage large gears. The serial numbers 4-1, 4-2, and 4-3 are three second-stage pinions, which are evenly distributed around the center of the gearbox. The second-stage large gears 3 mesh with two adjacent second-stage pinions 4 respectively. A split is formed, and each transmits half of the power; while the second-stage pinion 4 bears the power and speed transmitted by the two connected second-stage large gears, and the power is transmitted to the third-stage large gear after confluence, so the second-stage transmission forms 3 inputs Branch and 3 output branches; the serial numbers 5-1, 5-2 and 5-3 indicated by the dotted line are three third-stage large gears, which are respectively located on the same transmission shaft 8 as the second-stage pinion. The arrangement above the transmission line makes full use of the space.

The third-stage planetary gear transmission system is a fixed-shaft external meshing transmission system, and the output power of the second-stage planetary gear transmission system is input by d third-stage large gears 5 of the third-stage planetary gear transmission system, and then passes through the third-stage large gears 5 of the third-stage planetary gear transmission system. The third-stage central pinion 6 is output to the generator of the wind turbine. The d third-stage large gears 5 are evenly meshed around the third-stage central pinion 6, and one of the third-stage large gears 5 is installed on the second transmission shaft. On the other cantilever end of the third stage, the third-stage central pinion 6 is located in the center of the gearbox and is connected to the generator.

The spatial arrangement structure of the third-stage planetary gear transmission system is shown in Figure 5 (with d=3 as an example), the serial numbers 5-1, 5-2, and 5-3 are three third-stage large gears, and the serial number 6 is the first The third-stage central pinion, the serial number 15 is the outer casing of the generator, and the cantilever end of the second transmission shaft where the third-stage large gear is installed extends into the outer casing 15 of the generator, so that the three third-stage large gears and the third-stage central small gear The gear 6 is located within the housing 15 of the generator. The three third-stage transmission large gears 5-1, 5-2, and 5-3 mesh with the third-stage central pinion 6 at the same time, a total of 3 branches input power, and the third-stage central pinion 6 outputs the power confluence .

In addition, the gear box adopts a multi-branch power split transmission structure. Due to manufacturing and assembly errors, there must be uneven power distribution in each branch. Therefore, in this embodiment, one gear in each meshing pair is used to reduce stiffness and increase flexibility. The way to solve this problem is to adopt a flexible pin structure, specifically in the form of a cantilever beam in the gear assembly, as shown in Figure 2, the first-stage external gear 2 is installed at the cantilever end of the first drive shaft, and the second-stage external gear 2 The pinion gear 4 is mounted on the cantilever end of the second transmission shaft, and the third-stage large gear 5 is mounted on the other cantilever end of the second transmission shaft.

Due to the large deformation of the cantilever beam structure after being stressed, it is easy to cause uneven force on the width of the gears on it. Therefore, the above gears are designed as special structures. After assembly, the cantilever beam ends are formed in the opposite direction of the cantilever beam, forming a total of 2 cantilever structure, the so-called flexible pin structure. Referring to FIG. 2 , the first-stage external gear 2 forms a flexible pin structure with the first transmission shaft, the second-stage pinion 4 forms a flexible pin structure with the cantilever end of the second transmission shaft, and the third-stage large gear 5 and the second transmission shaft form a flexible pin structure. The other end of the transmission shaft forms a flexible pin structure. When a tangential force is applied to the gear, the angular deflection caused by the bending of the drive shaft can be offset by the angular deflection caused by the bending of the gear from the other end in the opposite direction. The normal force causes the flex pin to tilt downward, while the The reaction moment causes the flexible pin to tilt upward, and the two opposite inclination amounts will cancel out, so that the overall performance of the planetary gear is not tilted, and the force is not biased, and each gear moves in parallel, so that the load is evenly distributed among each tooth width. .

To sum up, compared with the original compact semi-direct drive structure, the compact semi-direct drive wind turbine gearbox multi-branch power split transmission structure provided by the present invention can improve the transmission power under the premise of keeping the space unchanged. , which provides a solution for the limited transmission power of the gearbox structure of the traditional compact semi-direct drive wind turbine, which is worthy of promotion.

The above-mentioned embodiments are only preferred embodiments of the present invention, and are not intended to limit the scope of implementation of the present invention. Therefore, any changes made according to the shape and principle of the present invention should be included within the protection scope of the present invention.

Claims (2)

1. The multi-branch power split transmission structure of the gear box of the compact semi-direct drive wind turbine, including the first-stage planetary gear transmission system and the second-stage planetary gear transmission system, is characterized in that: also includes the third-stage planetary gear transmission system; The first-stage planetary gear transmission system is a fixed-shaft internal meshing transmission system, and the power is input by its first-stage inner gear (1), and then forms a plurality of branch outputs through its first-stage external gears (2). , the plurality of first-stage external gears (2) are evenly distributed in the first-stage inner gear (1), and mesh with the first-stage inner gear (1) respectively to distribute power evenly. The inner gear (1) is fixedly connected with the hub (11) of the wind turbine, wherein a first-stage outer gear (2) is mounted on the cantilever end of a transmission shaft (10), and the transmission shaft (10) is the first-stage outer gear (2). a transmission shaft, which is respectively supported on the gear case body (12) and the bearing seat plate (14) through the first bearing (9) and the second bearing (13), the bearing seat plate (14) and the gear case body (14). 12) Fixed as a whole; the second-stage planetary gear transmission system is a fixed-shaft external meshing transmission system, and the output power of the first-stage planetary gear transmission system is generated by a plurality of second-stage large gears of the second-stage planetary gear transmission system. (3) Input, and then output through its plurality of second-stage pinions (4), the second-stage large gears (3) are respectively meshed with their adjacent second-stage pinions (4) to form a split flow. Two second-stage large gears (3) and a plurality of second-stage pinions (4) are evenly distributed around the center of the gearbox, and one of the second-stage large gears (3) is mounted on the first transmission shaft and is located in the first Between the bearing (9) and the second bearing (13), one of the second-stage pinions (4) is mounted on the cantilever end of the other transmission shaft (8), which is the second transmission shaft , and is supported on the bearing seat plate (14) through the third bearing (7), both ends of the second transmission shaft are cantilever ends; the third-stage planetary gear transmission system is a fixed-shaft external meshing transmission system, the first The power output by the two-stage planetary gear transmission system is input by a plurality of third-stage large gears (5) of the third-stage planetary gear transmission system, and then output to the generator of the wind turbine through its third-stage central pinion (6). , the plurality of third-stage large gears (5) evenly mesh around the third-stage central pinion (6), and one of the third-stage large gears (5) is installed on the other cantilever end of the second transmission shaft, so The third-stage central pinion (6) is located in the center of the gearbox and is connected to the generator. 2. The compact semi-direct drive wind turbine gearbox multi-branch power split transmission structure according to claim 1, characterized in that: the cantilever end of the second transmission shaft where the third-stage large gear (5) is installed extends to In the casing (15) of the generator, the third stage bull gear (5) and the third stage sun pinion (6) are located in the casing (15) of the generator.

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