A double magnetic field modulation axial flux supercharging type magnetic gear wind driven generator
By employing an axial flux structure and an inner rotor three-layer stacked permanent magnet array topology in the wind turbine, combined with a stator core and a magnetic adjustment ring, the problems of large mechanical gearbox size and complex radial magnetic gear processing are solved, achieving efficient and low-cost wind energy conversion and low-wind-speed power generation, and improving the stability and efficiency of the motor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- QUFU NORMAL UNIV
- Filing Date
- 2026-04-14
- Publication Date
- 2026-07-21
AI Technical Summary
Existing semi-direct drive wind turbines have problems with large mechanical gearboxes, high mechanical wear, and high failure rate. In addition, radial coaxial magnetic gears are complex to manufacture and difficult to assemble, which affects the stability and efficiency of the motor.
The wind turbine adopts a dual magnetic field modulation magnetic gear structure with axial magnetic flux structure. It combines a novel permanent magnet array topology with a three-layer stacked structure of the inner rotor, integrates a speed-increasing magnetic gearbox and a generator, and achieves dual magnetic field modulation through the adjusting magnetic ring and stator core. The inner rotor adopts a spoke structure and a three-layer stacked permanent magnet array, while the outer rotor is fixed to the adjusting magnetic ring, and the adjusting magnetic ring rotates.
It achieves high-efficiency, low-cost, and low-loss wind energy conversion, reduces torque pulsation and mechanical vibration, has low-wind-speed power generation capability, reduces maintenance costs and mechanical failures, and improves the stability and efficiency of the motor.
Smart Images
Figure CN122437292A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a wind turbine generator, and more particularly to a dual-magnetic-field modulated axial flux speed-increasing magnetic gear wind turbine generator, belonging to the field of wind power generation. Background Technology
[0002] In the field of wind turbines, semi-direct-drive wind turbines, with speeds between permanent magnet direct-drive and doubly-fed induction generators (DFIGs), combine the advantages of both types and have become one of the mainstream models. Currently, semi-direct-drive wind turbines all use mechanical gearboxes for speed increase, i.e., a generator + mechanical gearbox structure. However, mechanical gearboxes rely on mechanical gear meshing, requiring a complex lubrication system. This results in problems such as large size, high mechanical wear, and high failure rate in existing structures. Once a failure occurs, maintenance costs are high, downtime is long, and significant economic losses result. Therefore, there is an urgent need to develop a speed-increasing wind turbine that is small in size, highly efficient, and low in cost, integrating the speed-increasing gearbox and generator into one unit. Clearly, mechanical gearboxes cannot meet this requirement.
[0003] Magnetic gears, as a novel transmission method, utilize the magnetic field modulation effect of a magnetic ring to achieve magnetic field coupling between the inner and outer rotors. Because there is no mechanical contact, they offer advantages such as no wear, no maintenance, no noise, no lubrication required, and overload protection, and have gained increasing attention and application in recent years. Magnetic gears possess physical isolation characteristics, require no lubrication, are small in size, lightweight, have low energy consumption, and transmit high torque. They can be integrated with generators to form speed-increasing magnetic gear composite generators, effectively eliminating mechanical losses generated in intermediate transmission links.
[0004] However, most traditional magnetic gear composite motors currently have a radial structure, using radial coaxial magnetic gears. But radial coaxial magnetic gears require two rotating parts, which leads to complex manufacturing and assembly difficulties, severely limiting their widespread application.
[0005] In contrast, axial flux geared hybrid motors have inherent advantages in magnetic circuit structure and force rectangular generation mechanism. Their disc-shaped structure endows the magnetic flux with the characteristic of being closed along the axis, and the rotor has a larger effective radius of action, giving the system inherent attributes such as short magnetic circuit, compact structure, and high torque density. With its significant advantages in extremely low-speed matching, high-density generation, and low-loss operation, it has become a research hotspot in the field of motors in recent years.
[0006] However, in existing axial flux gear composite motors, the permanent magnets of the inner and outer rotors are usually magnetized axially or tangentially. Although the structure is simple and easy to implement, it has limitations in torque density and torque ripple, which affect the smoothness and efficiency of the motor. Halbach permanent magnet arrays, through a unique magnetic field distribution design, can improve the magnetic field strength and reduce torque ripple, thereby optimizing motor performance. However, due to the single arrangement of traditional Halbach permanent magnet arrays, the magnetic field modulation efficiency is limited, resulting in problems such as low magnetic field utilization, large local magnetic leakage, insufficient output torque, or large torque ripple.
[0007] To address this, this invention proposes a novel three-layer stacked permanent magnet array topology for the inner rotor. Based on this array, a dual-magnetic-field modulated axial flux-increasing magnetic gear wind turbine integrating a speed-increasing magnetic gearbox and a generator is constructed. The proposed three-layer stacked permanent magnet array topology effectively suppresses bypass leakage and local saturation at the magnetic bridge by introducing tangential magnetization auxiliary magnetomotive force layers on both sides of the axially magnetized main magnetic circuit and reconstructing the magnetic flux path with the intermediate magnetic guiding layer. This significantly enhances magnetization and magnetic modulation performance, achieving goals such as low energy consumption, high efficiency, low torque pulsation, and high torque density. Summary of the Invention
[0008] The main objective of this invention is to address the shortcomings and gaps in existing technologies by providing a dual-magnetic-field-modulated axial flux-increasing magnetic gear wind turbine. It employs an axial flux structure, achieving dual magnetic field modulation through a magnetic ring and stator core. Combined with a novel permanent magnet array topology featuring a three-layer stacked internal rotor structure, it integrates the functions of a magnetic gearbox, generator, and motor into one unit. This design offers advantages such as ease of manufacturing and assembly, small size, high efficiency, and low cost. It can not only efficiently convert wind energy into electrical energy under normal wind speed conditions but also function as a motor below the cut-in wind speed, assisting in starting the wind turbine and reducing starting resistance torque, thus achieving low-wind-speed power generation.
[0009] To achieve the above objectives, this invention provides a dual-magnetic-field modulated axial flux-increasing magnetic gear wind turbine, comprising: an outer rotor, a magnetic adjustment ring, an inner rotor, a stator, and a main shaft, a high-speed shaft, bearings, and a base, all arranged axially. The outer rotor is fixed to the main shaft, which is fixed to the wind turbine's rotor; the inner rotor is fixed to the high-speed shaft; the high-speed shaft is fixed to the base via bearings; the magnetic adjustment ring is fixed to the base; the outer rotor includes an outer rotor core and an outer rotor permanent magnet; the magnetic adjustment ring includes magnetic adjustment teeth and a support block; the stator includes a stator core and stator windings, with the stator core also serving as an auxiliary magnetic adjustment mechanism; the inner rotor adopts a spoke structure; and the outer rotor, magnetic adjustment ring, inner rotor, and stator are all disc structures; the outer rotor, magnetic adjustment ring, inner rotor, and stator core form a three-layer air-gap axial structure.
[0010] Each magnetic pole of the inner rotor includes a main permanent magnet segment and a lateral permanent magnet segment located on one side of the main permanent magnet segment, forming a three-layer stacked permanent magnet array. The topology of the three-layer stacked permanent magnet array is as follows: the main permanent magnet segment is an axially magnetized permanent magnet; the lateral permanent magnet segment has an upper, middle, and lower three-layer structure, with the upper and lower layers being tangentially magnetized permanent magnet layers with identical structures, and the middle layer being an iron core. The tangentially magnetized permanent magnet layer includes two tangentially magnetized permanent magnet units, and the magnetization direction of each tangentially magnetized permanent magnet unit is towards its adjacent main permanent magnet segment. A pair of poles of the inner rotor includes two magnetic poles, with the magnetization directions of their main permanent magnet segments opposite, and their lateral permanent magnet segments being identical.
[0011] The outer rotor, adjusting magnetic ring, and inner rotor constitute a magnetic gear. The number of pole pairs of the stator is the same as the number of pole pairs of the inner rotor, and the stator and inner rotor constitute a permanent magnet synchronous generator.
[0012] Furthermore, in the above scheme, in order to improve the speed ratio, the outer rotor is fixed to the machine base, while the adjusting magnetic ring is fixed to the main shaft. That is, the adjusting magnetic ring is a rotating component, while the outer rotor is fixed; the rest are the same.
[0013] The beneficial effects of this invention are:
[0014] 1) The novel three-layer stacked permanent magnet array topology proposed in this invention, as well as the auxiliary magnetic adjustment function of the stator core, greatly enhances the magnetic focusing and magnetic adjustment performance, which can significantly improve the electromagnetic performance of the generator, improve the sinusoidal nature of the air gap magnetic flux, thereby improving the generator efficiency and reducing torque pulsation.
[0015] 2) This invention integrates a speed-increasing magnetic gearbox and a generator into one unit. It adopts a disc structure, which is compact and has the advantages of simple manufacturing and assembly, small size, high efficiency, low cost, light weight, low energy consumption, and high reliability.
[0016] 3) Because the magnetic gearbox has no mechanical meshing and is a non-contact transmission, it achieves mechanical isolation. The mechanical vibration of the wind turbine will not be transmitted to the generator, which can effectively solve the inherent resonance and noise problems of mechanical wind turbine gearboxes. In addition, except for the bearings, there is no need for lubrication, which eliminates the need for a complex and cumbersome oil lubrication and cooling system, and can greatly reduce the operation and maintenance costs of wind turbines.
[0017] 4) This invention can not only efficiently convert wind energy into electrical energy under normal wind speed conditions, but also be used as an electric motor when the wind speed is lower than the cut-in wind speed to assist in starting the wind turbine rotation, reduce the starting resistance torque, and realize low wind speed power generation. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the structure of the axial flux gear wind turbine generator with dual magnetic field modulation according to the present invention.
[0019] Figure 2 This is a schematic diagram of a three-dimensional model of the axial flux gear wind turbine generator with dual magnetic field modulation according to the present invention.
[0020] Figure 3 This is a schematic diagram of the high speed ratio scheme of the axial flux gear wind turbine generator with dual magnetic field modulation of the present invention.
[0021] Figure 4 This is a schematic diagram of a three-dimensional model of the spoke-type internal rotor structure of the present invention.
[0022] Figure 5 This is a schematic diagram of the three-layer stacked permanent magnet array topology of the spoke-type inner rotor of the present invention.
[0023] Figure 6 A schematic diagram of a three-dimensional model of a spoke-type internal rotor structure that is axially magnetized.
[0024] Figure 7 This is a schematic diagram of the magnetic circuit of the axial flux gear wind turbine generator with dual magnetic field modulation according to the present invention.
[0025] Figure 8 This is a schematic diagram of the magnetic circuit of an axial flux gear wind turbine generator that uses an axially magnetized permanent magnet.
[0026] Figure 9 This is a magnetic flux density diagram of the inner rotor of an axial flux gear wind turbine generator that uses axially magnetized permanent magnets.
[0027] Figure 10 This is the magnetic flux density diagram of the inner rotor of the present invention.
[0028] Figure 11 This is a comparison curve of the no-load back electromotive force of the present invention and a generator using an axially magnetized permanent magnet.
[0029] Figure 12 This is a comparison curve of the external rotor torque of the present invention and a generator using axially magnetized permanent magnets.
[0030] Figure 13 This is a comparison curve of the internal rotor torque of the present invention and a generator using axially magnetized permanent magnets.
[0031] Among them, 1-outer rotor; 2-magnetic ring; 3-inner rotor; 4-stator; 5-main shaft; 6-high-speed shaft; 7-bearing; 8-frame; 9-wind wheel; 11-outer rotor core; 12-outer rotor permanent magnet; 21-magnetic block; 31-main permanent magnet segment; 32-lateral permanent magnet segment; 33-core; 34-tangentially magnetized permanent magnet unit; 35-axially magnetized permanent magnet; 36-inner rotor core; 41-stator core; 42-stator winding. Detailed Implementation
[0032] The present invention will now be described in further detail with reference to the accompanying drawings.
[0033] like Figure 1 , Figure 2 , Figure 7 As shown, this invention discloses an axial flux-increasing magnetic gear wind turbine with dual magnetic field modulation, comprising: an outer rotor 1, a magnetic adjustment ring 2, an inner rotor 3, a stator 4 arranged axially, as well as a main shaft 5, a high-speed shaft 6, bearings 7, and a base 8. The outer rotor 1 is fixed to the main shaft 5, and the main shaft 5 is fixed to the wind turbine rotor 9; the inner rotor 3 is fixed to the high-speed shaft 6; the high-speed shaft 6 is fixed to the base 8 via the bearings 7; the magnetic adjustment ring 2 is fixed to the base 8; the outer rotor 1 includes an outer rotor core 11 and an outer rotor permanent magnet 12, adopting a surface-mounted permanent magnet structure, with the outer rotor permanent magnet 12 mounted on the air gap side surface of the outer rotor yoke. The magnetic adjustment ring 2 includes a magnetic adjustment block 21 and a support block, which are arranged at even intervals along the circumference. The support block is used to support and fix the magnetic adjustment block 21. The stator 4 includes a stator core 41 and a stator winding 42. The stator core 41 also has an auxiliary magnetic adjustment function. The inner rotor 3 adopts a spoke structure. The outer rotor 1, magnetic adjustment ring 2, inner rotor 3, and stator 4 are all disc structures. The outer rotor 1, magnetic adjustment ring 2, inner rotor 3, and stator core 41 form a three-layer air gap axial structure.
[0034] The outer rotor 1, the adjusting magnetic ring 2, and the inner rotor 3 constitute a magnetic gear. The number of pole pairs of the outer rotor 1 is p. o The number of pole pairs p of the inner rotor 3 in The sum equals the number N of the adjusting magnetic block 21. s That is, N s =p o +p in .
[0035] In the above scheme, the speed increase ratio of the magnetic gear is G1 = p o / p in To increase the growth rate, such as Figure 3 As shown, the outer rotor 1 can be fixed to the base 8, while the adjusting magnetic ring 2 can be fixed to the main shaft 5. That is, the adjusting magnetic ring 2 rotates while the outer rotor 1 remains fixed; the rest of the parts are the same as the above scheme. In this case, the speed increase ratio of the magnetic gear G2 = N. s / p in =1+ p o / p in =1+ G1.
[0036] The number of pole pairs of stator 4 is the same as the number of pole pairs of inner rotor 3. Inner rotor 3 and stator 4 constitute a permanent magnet synchronous generator.
[0037] like Figure 4As shown, the inner rotor 3 adopts a spoke structure. Each magnetic pole of the inner rotor 3 includes a main permanent magnet segment 31 and a lateral permanent magnet segment 32 located on one side of the main permanent magnet segment 31, so as to form a three-layer stacked permanent magnet array.
[0038] Figure 5 This is a schematic diagram of the topological structure of the three-layer stacked permanent magnet array of the inner rotor 3 of the present invention. The topological structure of the three-layer stacked permanent magnet array is as follows: the main permanent magnet segment 31 is an axially magnetized permanent magnet; the lateral permanent magnet segment 32 has an upper, middle, and lower three-layer structure; the upper and lower layers are tangentially magnetized permanent magnet layers with identical structures; the middle layer is an iron core 33; the tangentially magnetized permanent magnet layer includes two tangentially magnetized permanent magnet units 34, and the magnetization direction of each tangentially magnetized permanent magnet unit is towards its adjacent main permanent magnet segment 31. A pair of poles of the inner rotor 3 includes two magnetic poles; the magnetization directions of their main permanent magnet segments 31 are opposite, while their lateral permanent magnet segments 32 are identical. As an example, from... Figure 4 It can be seen that the magnetization direction of the main permanent magnet segment 31 of the left magnetic pole is downward, while the magnetization direction of the main permanent magnet segment 31 of the right magnetic pole is upward; the lateral permanent magnet segments 32 of the left and right magnetic poles are the same. The upper and lower tangential magnetized permanent magnet layers have the same structure, each including a tangential magnetized permanent magnet unit 34 with the magnetization direction facing left and a tangential magnetized permanent magnet unit 34 with the magnetization direction facing right, while the middle layer is a silicon steel sheet core 33 with the same structure.
[0039] The present invention will be further described below using a preferred embodiment.
[0040] Taking a 5kW axial flux gear wind turbine generator with dual magnetic field modulation of the present invention as an example, its technical parameters are shown in Table 1, and its structural parameters are shown in Table 2. The adjusting ring 2 is fixed to the base 8, the outer rotor 1 is fixed to the main shaft 5, and the permanent magnet 12 of the outer rotor adopts a Halbach 90° permanent magnet array.
[0041] Table 1. Technical parameters of the 5kW dual-magnetic-field modulated axial flux gear wind turbine of this invention.
[0042]
[0043] Table 2 Structural parameters of the 5kW dual-magnetic-field modulated axial flux gear wind turbine of this invention
[0044]
[0045] To illustrate the advantages of the three-layer stacked permanent magnet array structure of the inner rotor of the present invention, an axial flux gear wind turbine with an axially magnetized permanent magnet in the inner rotor is selected as the comparative analysis object. Figure 6A three-dimensional model of an axially magnetized inner rotor structure is shown. The spoke-type inner rotor consists of an axially magnetized permanent magnet 35 and an inner rotor core 36, which are placed at even intervals along the circumferential direction.
[0046] Figure 7 and Figure 8 These are schematic diagrams of the magnetic circuits of the present invention and a generator employing an axially magnetized inner rotor, respectively.
[0047] from Figure 7 As can be seen, this invention retains the axially magnetized permanent magnet as the main magnetic flux source, thus ensuring that the air gap magnetic flux and voltage establishment capability do not decrease significantly due to topological changes, allowing structural improvements to more robustly focus on leakage flux suppression and waveform improvement. Simultaneously, the introduction of tangentially magnetized permanent magnet layers on both axial sides provides a more designable magnetomotive force distribution in the circumferential direction. When superimposed with the axial main magnetic field, this is expected to enhance the magnetic field components more favorable for magnetic field modulation coupling and suppress some ineffective harmonics, providing topological support for reducing back EMF distortion and torque pulsation from a mechanistic perspective. Furthermore, the intermediate silicon steel core 33, as a magnetic conductive layer, guides and reconstructs the magnetic flux path, weakening the tendency for magnetic flux to close nearby within the inner rotor to form a bypass, allowing more magnetic flux to cross the working air gap and participate in coupling, thereby reducing the saturation sensitivity area and improving the uniformity of magnetic flux distribution. Meanwhile, the stator core 41 acts as an auxiliary tuning ring, thus achieving dual magnetic field modulation together with the tuning ring 2, further suppressing leakage flux and enhancing the magnetic field modulation effect.
[0048] from Figure 8 It can be seen that the axial flux gear wind turbine with axially magnetized permanent magnets, whose inner rotor uses axially magnetized permanent magnets 35, produces a certain "magnetic flux convergence" effect, which is beneficial to improving the equivalent air gap flux linkage and the potential build-up capability. However, the magnetic flux generated by the axially magnetized permanent magnets 35 tends to close near the inner rotor core 36 through a low magnetic reluctance path, forming inter-pole bypass flux. This results in a reduction in the proportion of effective magnetic flux participating in the dual air gap coupling and magnetic field modulation, i.e., there is a significant leakage flux (bypass flux) phenomenon.
[0049] Figure 9 , Figure 10 The magnetic flux density diagrams are those of an inner rotor with axial magnetization and the inner rotor of the present invention, respectively.
[0050] from Figure 9It can be seen that the magnetic flux density cloud map of the inner rotor with axial magnetization exhibits a more significant "strong non-uniformity" characteristic: on the one hand, there is a large range of low to medium magnetic flux density regions in the inner rotor core; on the other hand, there is obvious magnetic flux density at the magnetic bridge, magnet edge and local sharp corner of the spoke structure, with the peak magnetic flux density exceeding 2T, and the magnetic flux density contour lines show a local "vortex" distribution pattern, indicating that the inner rotor has both magnetic bridge saturation and inter-pole bypass leakage magnetic flux, which reduces the effective coupling magnetic flux and introduces additional harmonics.
[0051] from Figure 10 It can be seen that, compared to the severe local saturation phenomenon at the magnetic bridge in an inner rotor using axial magnetization, the inner rotor of this invention, through the reconstruction effect of the intermediate magnetic conductive layer, allows the magnetic flux to be guided more evenly to the working air gap side, thus improving the magnetic energy utilization rate of the permanent magnet. Therefore, the three-layer stacked permanent magnet array topology of the inner rotor of this invention can enable wind turbines to have better performance.
[0052] Figure 11 The graph shows a comparison of the no-load back electromotive force (EMF) of the present invention and a generator using axially magnetized permanent magnets. As can be seen from the graph, the no-load back EMF amplitude of the present invention reaches 311V, the total harmonic distortion (THD) of the back EMF is reduced to 2.6%, and the waveform exhibits good sinusoidal characteristics. In contrast, the back EMF THD of the generator using axially magnetized permanent magnets reaches 11.47%, indicating that the three-layer stacked permanent magnet array topology of the inner rotor structure of the present invention can effectively reduce the high-order harmonic components in the air gap magnetic field.
[0053] Figure 12 This is a comparison curve of the external rotor torque of the present invention and a generator using axially magnetized permanent magnets. As can be seen from the figure, compared to the generator using axially magnetized permanent magnets, under rated load, the average output torque of the external rotor of the present invention increases from 507.8 Nm to 665.2 Nm, and the torque ripple decreases from 38% to 4.5%, indicating a significant increase in torque density and a significant reduction in torque ripple of the external rotor.
[0054] Figure 13 This is a comparison curve of the inner rotor torque of the present invention and a generator using axially magnetized permanent magnets. As can be seen from the figure, compared with the generator using axially magnetized permanent magnets, under rated load, the average output torque of the inner rotor of the present invention increases from 121.6 Nm to 161.5 Nm, and the torque ripple decreases from 55% to 4.8%, indicating a significant improvement in torque density and a significant reduction in torque ripple. This verifies the effectiveness of the three-layer stacked permanent magnet array topology of the inner rotor of the present invention in improving the air gap magnetic field distribution, reducing leakage flux, and improving material utilization.
[0055] Table 3 compares the performance indicators of the present invention with those of an axially magnetized axial flux gear wind turbine. As can be seen from Table 3, the performance indicators of the present invention are significantly improved, achieving a comprehensive balance between compactness, low-speed adaptability, and power quality. While maintaining good power quality, it significantly improves the torque capacity per unit volume, better meeting the low-speed, high-torque input characteristics of low-wind-speed wind farms.
[0056] Table 3 Comparison of performance indicators of the present invention and the internal rotor axial magnetizing generator.
[0057]
[0058] This invention discloses an axial flux gear wind turbine with dual magnetic field modulation, the working process of which is as follows:
[0059] When the wind speed is lower than the cut-in wind speed, the wind turbine of this invention operates in motor + deceleration mode: when the stator winding 42 is energized, the stator 4 and the inner rotor 3 form a motor, and the inner rotor 3 rotates; the inner rotor 3 is decelerated by the magnetic gearbox formed by the inner rotor 3, the adjusting magnetic ring 2, and the outer rotor 1, which drives the outer rotor 1 to rotate, thereby rotating the main shaft 5 and driving the wind turbine 9 to rotate; at this time, the magnetic gearbox is a reduction gearbox, and the wind turbine of this invention is equivalent to a permanent magnet synchronous motor with a reducer, which assists in starting the wind turbine to rotate, reduces the starting resistance torque, and thus realizes low wind speed power generation.
[0060] When the wind speed approaches the cut-in wind speed, according to Newton's second law, the rotational speed of the wind turbine 9 can easily reach the grid-connected speed. At this time, the wind turbine of this invention operates in the speed-up + generator mode: the wind turbine 9 rotates, driving the main shaft 5 to rotate, the main shaft 5 drives the outer rotor 1 to rotate, the outer rotor 1 is speed-up through the magnetic gearbox composed of the outer rotor 1, the adjusting magnetic ring 2, and the inner rotor 3, driving the inner rotor 3 to rotate, and the stator 4 and the inner rotor 3 constitute the generator, then the stator winding 42 outputs current, and the generator starts to generate electricity.
[0061] Therefore, the internal rotor of this invention adopts a three-layer stacked permanent magnet array topology, which results in high flux modulation utilization and advantages such as high torque density and low torque ripple. Simultaneously, by integrating the speed increaser and generator into one unit, the overall size and weight can be significantly reduced, achieving the goals of lightweight, miniaturized, low-cost, high-efficiency, and high-power-quality motors. Furthermore, the axial flux gear wind turbine generator with dual magnetic field modulation of this invention can not only efficiently convert wind energy into electrical energy under normal wind speed conditions, but can also be used as a motor at wind speeds below the cut-in wind speed to assist in starting the wind turbine rotation, reduce starting resistance torque, and achieve low-wind-speed power generation.
Claims
1. A dual-magnetic-field modulated axial flux-increasing magnetic gear wind turbine, characterized in that: include: The system comprises an outer rotor, a magnetic adjustment ring, an inner rotor, a stator, a main shaft, a high-speed shaft, bearings, and a base, all arranged axially. The outer rotor is fixed to the main shaft, which is in turn fixed to the wind turbine's rotor. The inner rotor is fixed to the high-speed shaft, which is then fixed to the base via bearings. The magnetic adjustment ring is also fixed to the base. The outer rotor includes an outer rotor core and an outer rotor permanent magnet. The magnetic adjustment ring includes magnetic adjustment teeth and a support block. The stator includes a stator core and stator windings, with the stator core also serving as an auxiliary magnetic adjustment mechanism. The inner rotor has a spoke-type structure. The outer rotor, magnetic adjustment ring, inner rotor, and stator are all disc-type structures.
2. The axial flux-increasing magnetic gear wind turbine generator with dual magnetic field modulation according to claim 1, characterized in that: Each magnetic pole of the inner rotor includes a main permanent magnet segment and a lateral permanent magnet segment located on one side of the main permanent magnet segment, forming a three-layer stacked permanent magnet array. The topology of the three-layer stacked permanent magnet array is as follows: the main permanent magnet segment is an axially magnetized permanent magnet; the lateral permanent magnet segment has an upper, middle, and lower three-layer structure, with the upper and lower layers being tangentially magnetized permanent magnet layers with the same structure, and the middle layer being an iron core; the tangentially magnetized permanent magnet layer includes two tangentially magnetized permanent magnet units, and the magnetization direction of each tangentially magnetized permanent magnet unit is towards its adjacent main permanent magnet segment.
3. The axial flux-increasing magnetic gear wind turbine generator with dual magnetic field modulation according to claim 2, characterized in that: The inner rotor has two poles, with the main permanent magnet segments of the two poles having opposite magnetization directions and the lateral permanent magnet segments of the two poles having the same direction.
4. The axial flux-increasing magnetic gear wind turbine generator with dual magnetic field modulation according to claim 1, characterized in that: The outer rotor, adjusting ring, and inner rotor constitute a magnetic gear.
5. The axial flux-increasing magnetic gear wind turbine generator with dual magnetic field modulation according to claim 1, characterized in that: The number of pole pairs of the stator is equal to the number of pole pairs of the inner rotor, and the stator and the inner rotor constitute a permanent magnet synchronous generator.
6. The axial flux-increasing magnetic gear wind turbine generator with dual magnetic field modulation according to claim 1, characterized in that: To increase the speed ratio, the outer rotor is fixed to the machine base, while the adjusting magnetic ring is fixed to the main shaft. That is, the adjusting magnetic ring is a rotating component, while the outer rotor is fixed; the rest are the same.