Transmission chain structure of vertical axis wind turbine generator and control method

Abstract

The transmission chain structure comprises an expansion sleeve, one end of the expansion sleeve is connected with a blade shaft of a fan blade, the other end of the expansion sleeve is connected with a main shaft, and the main shaft is connected with the input end of a planetary gear transmission mechanism in a gearbox; the output end of the planetary gear transmission mechanism is connected with the input end of the second-stage parallel transmission mechanism; the output end of the second-stage parallel transmission mechanism is connected with the third-stage parallel gear transmission mechanism, and the output end of the third-stage parallel gear transmission mechanism is connected with the generator. By the adoption of the transmission chain structure, reliable, safe, efficient and stable operation of the transmission chain can be achieved, the transmission distance of the transmission chain of the vertical axis fan is shortened, the wind speed range of effective power generation of the vertical axis fan is expanded, and the wind energy capturing efficiency and the power generation capacity of the vertical axis fan are improved.

Description

Technical Field

[0001] The invention relates to the field of wind turbines, and in particular to a transmission chain structure and a control method of a vertical axis wind turbine set. Background Art

[0002] As a renewable natural resource, wind energy has the characteristics of recycling and continuous supply. It is not only abundant in reserves, but also clean and does not produce pollutants during its use. Another major advantage of wind power generation is its relatively short construction period and high flexibility in installed capacity. It can occupy less land resources while almost avoiding the occupation of arable land. Therefore, wind power generation projects have shown good performance in both economic and social benefits. In recent years, with the continuous progress of wind power generation technology and related theories, governments and all sectors of society around the world have paid close attention to and attached great importance to the development of wind power generation technology.

[0003] Contemporary wind power generation devices are mainly divided into two categories: horizontal axis wind turbines and vertical axis wind turbines. Among them, horizontal axis wind turbines are more traditional types. Due to the existence of wake problems, they need to be separated by a large distance and occupy a large area. Vertical axis wind turbines have almost no wake problems, so they can be arranged more compactly and can even provide power in complex areas such as urban agglomerations. Therefore, it greatly saves land, improves the power generation and power generation efficiency of wind turbines, and has broad development prospects. Summary of the invention

[0004] The present invention provides a novel vertical axis wind turbine transmission chain structure and control method, which can realize reliable, safe, efficient and stable operation of the transmission chain, shorten the transmission distance of the vertical axis wind turbine transmission chain, expand the wind speed range for effective power generation of the vertical axis wind turbine, and improve the wind energy capture efficiency and power generation of the vertical axis wind turbine.

[0005] In order to realize the above-mentioned technical features, the object of the present invention is realized as follows: a vertical axis wind turbine transmission chain structure, comprising a expansion sleeve, one end of which is connected to the blade shaft of the wind turbine blade, and the other end is connected to the main shaft, and the main shaft is connected to the input end of the planetary gear transmission mechanism inside the gear box; the output end of the planetary gear transmission mechanism is connected to the input end of the second-stage parallel transmission mechanism; the output end of the second-stage parallel transmission mechanism is connected to the third-stage parallel gear transmission mechanism, and the output end of the third-stage parallel gear transmission mechanism is connected to the generator.

[0006] The planetary gear transmission mechanism includes a planet carrier, an inner gear ring, a sun gear and planetary wheels. The main shaft is connected to the planet carrier, and the planetary wheels are installed on the planet carrier. The planetary wheels are meshed with the inner gear ring and the sun gear for transmission. The inner gear ring is fixed between the front and rear boxes of the gear box.

[0007] The second stage parallel transmission mechanism comprises a first large gear, a second large gear, a third large gear and a fourth large gear coaxially connected to the main shaft of the sun gear, the first large gear meshes with the first small gear, the second large gear meshes with the second small gear, the third large gear meshes with the third small gear, and the fourth large gear meshes with the fourth small gear; It also includes a first electromagnetic clutch and a second electromagnetic clutch, and the first electromagnetic clutch and the second electromagnetic clutch are used to respectively control the meshing of gears with different transmission ratios to adapt to working conditions under different wind speeds.

[0008] The first electromagnetic clutch controls the meshing of the first pinion gear and the first large gear and the second pinion gear and the second large gear; The second electromagnetic clutch controls the meshing conditions of the third pinion gear and the third large gear and the fourth pinion gear and the fourth large gear.

[0009] The third-stage parallel gear transmission mechanism comprises a fifth pinion gear, which is meshed with a fifth large gear; and the fifth large gear is coaxially connected with the fourth pinion gear.

[0010] The generator comprises a front end cover, a generator bearing, a generator rotor, a generator stator, an output coil and a rear end cover; the generator rotor is connected to the fifth pinion.

[0011] The entire transmission chain structure adopts a semi-direct drive structure. The generator is small in size, which reduces the requirements on the generator performance, and improves the transmission efficiency through a low transmission ratio gear set.

[0012] The angle of the fan blades can be adjusted according to the wind speed. When the wind speed exceeds the cut-out wind speed, the blade angle is adjusted to a feathering position to reduce the force on the blades and avoid overload.

[0013] A control method for a transmission chain structure of a vertical axis wind turbine: The wind drives the blade shaft to rotate, thereby transmitting the power to the main shaft through the expansion sleeve. The main shaft is connected to the planetary frame in the planetary gear rotation mechanism. The power is input by the planetary frame, and is output by the sun gear after the speed is increased by the planetary gear rotation mechanism. In the second-stage parallel transmission of the second-stage parallel transmission mechanism, the first small gear and the first large gear are externally meshed, the second large gear and the second small gear are externally meshed, the third small gear and the third large gear are externally meshed, and the fourth large gear and the fourth small gear are externally meshed. In the second-stage parallel transmission, whether these four pairs of gears are specifically meshed depends on the control of the first electromagnetic clutch and the second electromagnetic clutch; and then the power is transmitted to the generator through the third-stage parallel gear transmission mechanism. In the transmission chain of this vertical axis wind turbine, in order to control the wind speed received by the generator within the optimal power generation range under different wind speeds, the transmission ratio is adjusted by using the second electromagnetic clutch and the first electromagnetic clutch in the planetary gear rotation mechanism to adapt to different wind conditions.

[0014] When the wind speed is higher than the cut-in wind speed but lower than the rated wind speed, the two low-speed gears are adjusted, and according to the specific real-time wind speed, the first electromagnetic clutch is used to control the meshing of the first small gear and the first large gear, and the second large gear and the second small gear; wherein the first small gear and the first large gear are of high transmission ratio, and the second large gear and the second small gear are of low transmission ratio, wherein the high transmission ratio and the low transmission ratio represent the comparison of the two pairs of meshing gears; when the wind speed is within this range but less than a certain value, the clutch controls the meshing of the gear set with a large transmission ratio; when the wind speed is within this range but greater than a certain value, the clutch controls the meshing of the gear set with a small transmission ratio; When the wind speed is higher than the rated wind speed but lower than the cut-out wind speed, the two high-speed gears are adjusted, and according to the specific real-time wind speed, the meshing of the third small gear and the third large gear, and the fourth large gear and the fourth small gear is controlled by the second electromagnetic clutch, wherein the third small gear and the third large gear are of high transmission ratio, and the fourth large gear and the fourth small gear are of low transmission ratio, wherein the high transmission ratio and the low transmission ratio represent the comparison of the two pairs of meshing gears; when the wind speed is within this range but less than a certain value, the clutch controls the meshing of the gear set with a larger transmission ratio; when the wind speed is within this range but greater than a certain value, the clutch controls the meshing of the gear set with a smaller transmission ratio; When the wind speed is higher than the cut-out wind speed, the blade angle of the vertical axis wind turbine is adjusted to the feathering position, the angle between the blade and the wind direction increases, causing the blade to enter the stall zone and reduce the force on the blade. At the same time, based on the comparison between the adjusted wind force and the cut-out wind speed, it is determined whether to cut off the power generation system to prevent the motor from being overloaded or damaged.

[0015] The present invention has the following beneficial effects: 1. The transmission chain structure of the vertical axis wind turbine proposed in the present invention adopts a semi-direct drive structure. Compared with direct drive, it reduces the size of the motor and reduces the high requirements for the motor. Compared with the traditional high-speed type, the transmission chain can adopt a lower transmission ratio. It can realize reliable, safe, efficient and stable operation of the transmission chain, expand the wind speed range of effective power generation of the wind turbine, and improve the wind energy capture efficiency and power generation of the vertical axis wind turbine.

[0016] 2. In the planetary gear transmission mechanism of the present invention, transmission is performed by three shafts with the same parameters and corresponding 3×4 pairs of gears, so the transmission is more stable.

[0017] 3. The present invention adjusts the specific transmission ratio in real time through the first electromagnetic clutch and the second electromagnetic clutch to adapt to different wind conditions, thereby expanding the wind speed range of effective power generation of the wind turbine and improving the wind energy capture efficiency and power generation of the vertical axis wind turbine. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0019] Figure 1 Overall schematic diagram of a vertical axis fan.

[0020] Figure 2 Schematic diagram of the internal structure of the vertical axis fan transmission system.

[0021] In the figure: fan blade 1, expansion sleeve 1a, main shaft 1b, blade shaft 1c; Planetary gear transmission mechanism 2, planet carrier 2a, inner ring gear 2b, sun gear 2c, planet gear 2d; Second-stage parallel transmission mechanism 3, first pinion 3a, first large gear 3b, first electromagnetic clutch 3c, second pinion 3d, second large gear 3e, third large gear 3f, third pinion 3g, second electromagnetic clutch 3h, fourth large gear 3i, fourth pinion 3j; Generator 4, front end cover 4a, generator bearing 4b, generator rotor 4c, generator stator 4d, output coil 4e, rear end cover 4f; Gear box 5, base 6. DETAILED DESCRIPTION

[0022] The embodiments of the present invention are further described below in conjunction with the accompanying drawings.

[0023] Embodiment 1: Reference Figure 1-2A transmission chain structure of a vertical axis wind turbine unit includes a locking sleeve 1a, one end of the locking sleeve 1a is connected to the blade shaft 1c of the wind turbine blade 1, and the other end is connected to the main shaft 1b, the main shaft 1b is connected to the input end of the planetary gear transmission mechanism 2 inside the gear box 5; the output end of the planetary gear transmission mechanism 2 is connected to the input end of the second-stage parallel transmission mechanism 3; the output end of the second-stage parallel transmission mechanism 3 is connected to the third-stage parallel gear transmission mechanism, and the output end of the third-stage parallel gear transmission mechanism is connected to the generator 4. By adopting the above-mentioned transmission chain structure, the transmission chain can be operated reliably, safely, efficiently and stably, the transmission distance of the vertical axis wind turbine transmission chain can be shortened, the wind speed range of the vertical axis wind turbine for effective power generation can be expanded, and the wind energy capture efficiency and power generation of the vertical axis wind turbine can be improved. During operation, the fan blade 1 drives the blade shaft 1c, the blade shaft 1c drives the expansion sleeve 1a, the expansion sleeve 1a drives the main shaft 1b, the main shaft 1b transmits power to the planetary gear transmission mechanism 2, the planetary gear transmission mechanism 2 drives the second-stage parallel transmission mechanism 3, the second-stage parallel transmission mechanism 3 drives the third-stage parallel gear transmission mechanism, the third-stage parallel gear transmission mechanism drives the generator 4, and then the generator 4 generates electricity.

[0024] Furthermore, the planetary gear transmission mechanism 2 includes a planet carrier 2a, an inner gear ring 2b, a sun gear 2c and a planetary gear 2d. The main shaft 1b is connected to the planet carrier 2a. The planetary gear 2d is installed on the planetary carrier 2a. The planetary gear 2d is meshed with the inner gear ring 2b and the sun gear 2c for transmission. The inner gear ring 2b is fixed between the front and rear housings of the gear box 5. The power of the fan blade 1 can be transmitted to the second-stage parallel transmission mechanism 3 through the above-mentioned planetary gear transmission mechanism 2. During the working process, the wind drives the blade shaft to rotate, thereby transmitting the power to the main shaft 1b through the expansion sleeve 1a. The main shaft 1b is connected to the planetary carrier 2a in the planetary gear transmission mechanism 2. The power is input from the planetary gear transmission planetary carrier 2a, and is output from the sun gear 2c after the speed is increased by the planetary gear transmission mechanism 2.

[0025] Furthermore, the second-stage parallel transmission mechanism 3 includes a first large gear 3b, a second large gear 3e, a third large gear 3f and a fourth large gear 3i which are coaxially connected to the main shaft of the sun gear 2c, wherein the first large gear 3b is meshed with the first small gear 3a, the second large gear 3e is meshed with the second small gear 3d, the third large gear 3f is meshed with the third small gear 3g, and the fourth large gear 3i is meshed with the fourth small gear 3j. In the second-stage parallel transmission mechanism 3, whether these four pairs of gears are specifically meshed or not depends on the control of the first electromagnetic clutch 3c and the second electromagnetic clutch 3h. Then, the power is transmitted to the generator 4 through the third-stage parallel gear transmission.

[0026] Furthermore, the first electromagnetic clutch 3c and the second electromagnetic clutch 3h are included, and the meshing of gears with different transmission ratios is controlled by the first electromagnetic clutch 3c and the second electromagnetic clutch 3h respectively to adapt to working conditions under different wind speeds. The first electromagnetic clutch 3c controls the meshing of the first pinion 3a and the first large gear 3b, and the second pinion 3d and the second large gear 3e; the second electromagnetic clutch 3h controls the meshing of the third pinion 3g and the third large gear 3f, and the fourth pinion 3j and the fourth large gear 3i.

[0027] Furthermore, the third-stage parallel gear transmission mechanism includes a fifth pinion 3k, which is meshed with a fifth large gear 3l; the fifth large gear 3l is coaxially connected with the fourth pinion 3j.

[0028] Furthermore, the generator 4 includes a front cover 4a, a generator bearing 4b, a generator rotor 4c, a generator stator 4d, an output coil 4e and a rear cover 4f; the generator rotor 4c is connected to the fifth pinion 3k. The generator bearing 4b and the front cover 4a and the rear cover 4f respectively connect and assemble the generator rotor 4c, so that the generator rotor 4c can rotate in the generator stator 4d and cut the magnetic flux lines, thereby generating an induced potential and converting mechanical energy into electrical energy.

[0029] Furthermore, the entire transmission chain structure adopts a semi-direct drive structure, the size of the generator 4 is small, the requirements for the performance of the generator 4 are reduced, and the transmission efficiency is improved through a low transmission ratio gear set.

[0030] Furthermore, the angle of the wind turbine blade 1 can be adjusted according to the wind speed. When the wind speed exceeds the cut-out wind speed, the blade angle is adjusted to a feathering position to reduce the force on the blade and avoid overload.

[0031] Embodiment 2: A control method for a transmission chain structure of a vertical axis wind turbine: The wind drives the blade shaft 1c to rotate, thereby transmitting the power to the main shaft 1b through the expansion sleeve 1a. The main shaft 1b is connected to the planet carrier 2a in the planetary gear rotating mechanism 2. The power is input by the planet carrier 2a, and is output by the sun gear 2c after the speed is increased by the planetary gear rotating mechanism 2; in the second-stage parallel transmission of the second-stage parallel transmission mechanism 3, the first small gear 3a and the first large gear 3b are externally meshed, the second large gear 3e and the second small gear 3d are externally meshed, the third small gear 3g and the third large gear 3f are externally meshed, and the fourth large gear 3i and the fourth small gear 3j are externally meshed. In the second-stage parallel transmission, whether these four pairs of gears are specifically meshed depends on the control of the first electromagnetic clutch 3c and the second electromagnetic clutch 3h; and then the power is transmitted to the generator 4 through the third-stage parallel gear transmission mechanism; In the transmission chain of this vertical axis wind turbine, in order to control the wind speed received by the generator 4 within the optimal power generation range under different wind speeds, the transmission ratio is adjusted by means of the second electromagnetic clutch 3h and the first electromagnetic clutch 3c in the planetary gear rotation mechanism 2 to adapt to different wind conditions.

[0032] When the wind speed is higher than the cut-in wind speed but lower than the rated wind speed, the two low-speed gears are adjusted, and according to the specific real-time wind speed, the first electromagnetic clutch 3c is used to control the meshing of the first small gear 3a and the first large gear 3b, and the second large gear 3e and the second small gear 3d; wherein the first small gear 3a and the first large gear 3b are of high transmission ratio, and the second large gear 3e and the second small gear 3d are of low transmission ratio, wherein the high transmission ratio and the low transmission ratio represent the comparison of the two pairs of meshing gears; when the wind speed is within this range but less than a certain value, the clutch controls the meshing of the gear set with a large transmission ratio; when the wind speed is within this range but greater than a certain value, the clutch controls the meshing of the gear set with a small transmission ratio; When the wind speed is higher than the rated wind speed but lower than the cut-out wind speed, the two high-speed gears are adjusted. According to the specific real-time wind speed, the meshing of the third small gear 3g and the third large gear 3f, and the fourth large gear 3i and the fourth small gear 3j are controlled by the second electromagnetic clutch 3h, wherein the third small gear 3g and the third large gear 3f are of high transmission ratio, and the fourth large gear 3i and the fourth small gear 3j are of low transmission ratio, wherein the high transmission ratio and the low transmission ratio represent the comparison of the two pairs of meshing gears; when the wind speed is within this range but less than a certain value, the clutch controls the meshing of the gear set with a larger transmission ratio; when the wind speed is within this range but greater than a certain value, the clutch controls the meshing of the gear set with a smaller transmission ratio; When the wind speed is higher than the cut-out wind speed, the blade angle of the vertical axis wind turbine is adjusted to the feathering position, the angle between the blade and the wind direction increases, causing the blade to enter the stall zone and reduce the force on the blade. At the same time, based on the comparison between the adjusted wind force and the cut-out wind speed, it is determined whether to cut off the power generation system to prevent the motor from being overloaded or damaged.

Claims

1. A transmission chain structure of a vertical axis wind turbine, characterized in that: The invention comprises a expansion sleeve (1a), one end of which is connected to a blade shaft (1c) of a fan blade (1), and the other end of which is connected to a main shaft (1b); the main shaft (1b) is connected to the input end of a planetary gear transmission mechanism (2) inside a gear box (5); the output end of the planetary gear transmission mechanism (2) is connected to the input end of a second-stage parallel transmission mechanism (3); the output end of the second-stage parallel transmission mechanism (3) is connected to a third-stage parallel gear transmission mechanism; and the output end of the third-stage parallel gear transmission mechanism is connected to a generator (4).

2. A transmission chain structure of a vertical axis wind turbine according to claim 1, characterized in that: The planetary gear transmission mechanism (2) comprises a planet carrier (2a), an inner gear ring (2b), a sun gear (2c) and a planetary gear (2d); the main shaft (1b) is connected to the planet carrier (2a); the planetary gear (2d) is mounted on the planet carrier (2a); the planetary gear (2d) is meshed with the inner gear ring (2b) and the sun gear (2c) for transmission; the inner gear ring (2b) is fixed between the front and rear housings of the gear box (5).

3. A transmission chain structure of a vertical axis wind turbine according to claim 2, characterized in that: The second-stage parallel transmission mechanism (3) comprises a first large gear (3b), a second large gear (3e), a third large gear (3f) and a fourth large gear (3i) which are coaxially connected to the main shaft of the sun gear (2c), the first large gear (3b) meshing with the first small gear (3a), the second large gear (3e) meshing with the second small gear (3d), the third large gear (3f) meshing with the third small gear (3g), and the fourth large gear (3i) meshing with the fourth small gear (3j); It also comprises a first electromagnetic clutch (3c) and a second electromagnetic clutch (3h), and the meshing of gears with different transmission ratios is controlled respectively by the first electromagnetic clutch (3c) and the second electromagnetic clutch (3h) to adapt to working conditions under different wind speeds.

4. A transmission chain structure of a vertical axis wind turbine according to claim 3, characterized in that: The first electromagnetic clutch (3c) controls the meshing condition between the first pinion gear (3a) and the first large gear (3b) and between the second pinion gear (3d) and the second large gear (3e); The second electromagnetic clutch (3h) controls the meshing condition between the third small gear (3g) and the third large gear (3f) and between the fourth small gear (3j) and the fourth large gear (3i).

5. A transmission chain structure of a vertical axis wind turbine according to claim 4, characterized in that: The third-stage parallel gear transmission mechanism comprises a fifth pinion (3k), the fifth pinion (3k) meshing with a fifth large gear (3l); the fifth large gear (3l) is coaxially connected with a fourth pinion (3j).

6. A transmission chain structure of a vertical axis wind turbine according to claim 5, characterized in that: The generator (4) comprises a front end cover (4a), a generator bearing (4b), a generator rotor (4c), a generator stator (4d), an output coil (4e) and a rear end cover (4f); the generator rotor (4c) is connected to a fifth pinion (3k).

7. A transmission chain structure of a vertical axis wind turbine according to claim 6, characterized in that: The entire transmission chain structure adopts a semi-direct drive structure, the size of the generator (4) is small, the requirements for the performance of the generator (4) are reduced, and the transmission efficiency is improved through a gear set with a low transmission ratio.

8. A transmission chain structure of a vertical axis wind turbine according to claim 6, characterized in that: The angle of the fan blade (1) can be adjusted according to the wind speed; when the wind speed exceeds the cut-out wind speed, the blade angle is adjusted to a feathering position to reduce the force on the blade and avoid overload.

9. A control method for a transmission chain structure of a vertical axis wind turbine set according to any one of claims 7 to 8, characterized in that: The wind drives the blade shaft (1c) to rotate, thereby transmitting power to the main shaft (1b) through the expansion sleeve (1a). The main shaft (1b) is connected to the planetary frame (2a) in the planetary gear rotating mechanism (2). The power is input from the planetary frame (2a), and is output from the sun gear (2c) after the speed is increased by the planetary gear rotating mechanism (2). In the second-stage parallel transmission of the second-stage parallel transmission mechanism (3), the first small gear (3a) and the first large gear (3b) are externally meshed, the second large gear (3e) and the second small gear (3d) are externally meshed, the third small gear (3g) and the third large gear (3f) are externally meshed, and the fourth large gear (3i) and the fourth small gear (3j) are externally meshed. In the second-stage parallel transmission, whether these four pairs of gears are specifically meshed depends on the control of the first electromagnetic clutch (3c) and the second electromagnetic clutch (3h). Then, the power is transmitted to the generator (4) through the third-stage parallel gear transmission mechanism. In the transmission chain of this vertical axis wind turbine, in order to control the wind speed received by the generator (4) within the optimal power generation range under different wind speeds, the transmission ratio is adjusted by using the second electromagnetic clutch (3h) and the first electromagnetic clutch (3c) in the planetary gear rotation mechanism (2) to adapt to different wind conditions.

10. A control method for a transmission chain structure of a vertical axis wind turbine according to claim 9, characterized in that: When the wind speed is higher than the cut-in wind speed but lower than the rated wind speed, the two low-speed gears are adjusted, and according to the specific real-time wind speed, the meshing of the two pairs of gears, namely the first small gear (3a) and the first large gear (3b), and the second large gear (3e) and the second small gear (3d), is controlled by the first electromagnetic clutch (3c); wherein the first small gear (3a) and the first large gear (3b) have a high transmission ratio, and the second large gear (3e) and the second small gear (3d) have a low transmission ratio, wherein the high transmission ratio and the low transmission ratio represent the comparison between the two pairs of meshing gears; when the wind speed is within this range but less than a certain value, the clutch controls the meshing of the gear set with a large transmission ratio; and when the wind speed is within this range but greater than a certain value, the clutch controls the meshing of the gear set with a small transmission ratio; When the wind speed is higher than the rated wind speed but lower than the cut-out wind speed, the two high-speed gears are adjusted. According to the specific real-time wind speed, the meshing of the third small gear (3g) and the third large gear (3f), and the fourth large gear (3i) and the fourth small gear (3j) is controlled by the second electromagnetic clutch (3h), wherein the third small gear (3g) and the third large gear (3f) are of high transmission ratio, and the fourth large gear (3i) and the fourth small gear (3j) are of low transmission ratio, wherein the high transmission ratio and the low transmission ratio represent the comparison of the two pairs of meshing gears; when the wind speed is within this range but less than a certain value, the clutch controls the meshing of the gear set with a larger transmission ratio; when the wind speed is within this range but greater than a certain value, the clutch controls the meshing of the gear set with a smaller transmission ratio; When the wind speed is higher than the cut-out wind speed, the blade angle of the vertical axis wind turbine is adjusted to the feathering position, the angle between the blade and the wind direction increases, causing the blade to enter the stall zone and reduce the force on the blade. At the same time, based on the comparison between the adjusted wind force and the cut-out wind speed, it is determined whether to cut off the power generation system to prevent the motor from being overloaded or damaged.

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