A vertical axis outer rotor magnetic levitation wind turbine

Abstract

The present invention provides a vertical-axis outer rotor magnetic levitation wind turbine generator, comprising: a blade unit (rotating component) for collecting wind energy and converting it into rotational mechanical energy; a casing (rotating component) (a hollow cylinder with a top fixed to the bottom of the blade unit and capable of rotating synchronously with the blade unit); a main shaft (stationary component) (a vertically arranged cylinder with a top inserted into the interior of the casing); a support unit (encircling the main shaft and disposed between the casing and the main shaft, connecting the casing and the main shaft and providing support for the rotating component based on the main shaft); and a generator body (an outer rotor permanent magnet synchronous generator) comprising a generator stator sleeved and fixed on the main shaft and a generator rotor fixed within the casing, for converting the mechanical energy of the rotating component into electrical energy. The present invention has the advantages of a simple structure, a reasonable layout, low friction resistance, and a low starting wind speed, making it suitable for the field of breeze power generation.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a micro-wind magnetic suspension wind generator with low starting wind speed. Background Art

[0002] As traditional conventional energy sources, the excessive development and use of coal and oil have brought about environmental pollution and energy shortage problems. Under the influence of the dual crises of energy crisis and environmental pollution, countries around the world are researching, developing and utilizing clean energy and renewable energy.

[0003] Wind resources in my country are unevenly distributed. Areas rich in wind resources are mainly distributed in the northwest, southwest and north China, and large-scale wind power generation is mainly carried out through large wind turbines. The electricity load centers are mainly distributed in the eastern coastal areas and southern China. Most of them are low wind speed areas and cover a large area. However, due to the limitations of low wind speed power generation technology, low wind speed wind energy has not been fully developed and utilized, resulting in serious waste of resources.

[0004] Small wind turbines have emerged to meet the power generation needs of low-wind-speed wind farms, while also addressing the unsuitability of large wind turbines in urban and remote rural areas. Currently, most traditional small wind turbines use mechanical bearings, which have high friction resistance. Starting wind speeds must exceed 3.5 m / s, and generating wind speeds must exceed 4.2 m / s, resulting in generally low wind energy efficiency.

[0005] To address the high friction resistance of traditional wind turbines, some researchers have applied magnetic levitation support technology to small wind turbines, replacing traditional mechanical bearings with magnetic bearings to reduce friction and improve wind energy utilization. Currently, magnetic levitation wind turbines fall into two main categories: one that combines permanent magnetic bearings with mechanical bearings, leveraging the repulsive force of the permanent magnetic bearings to reduce the load on the mechanical bearings, thereby reducing friction resistance; the other that uses only electromagnetic bearings to achieve five-degree-of-freedom rotor suspension, achieving contactless support and completely eliminating mechanical friction.

[0006] While all of the above approaches can improve wind energy utilization, they all have drawbacks. Currently, permanent magnetic bearings combined with mechanical bearings have complex magnetic circuit structures, making assembly difficult, and they use a large amount of permanent magnet material, resulting in high costs and a disadvantageous environment for large-scale application. Full electromagnetic bearings have complex systems and require position sensors to provide position information, making control difficult and unreliable. Furthermore, electromagnetic bearings consume electricity, resulting in a limited overall energy efficiency advantage, which also restricts their widespread application. Therefore, simplifying the permanent magnetic bearing structure, reducing system complexity, and minimizing the amount of permanent magnets are urgent issues for the large-scale application of magnetically levitated wind turbines. Summary of the Invention

[0007] The purpose of the present invention is to provide a vertical axis outer rotor magnetic levitation wind turbine. In view of the defects of the existing technology, a vertical axis magnetic levitation wind turbine with a simple structure is provided to reduce friction resistance, lower the starting wind speed, and improve the utilization efficiency of breeze resources.

[0008] To achieve the above object, the present invention is implemented through the following technical solutions:

[0009] A vertical-axis outer rotor magnetic levitation wind turbine generator, comprising:

[0010] The wind blade unit is a rotating component used to collect wind energy and convert it into rotational mechanical energy;

[0011] The housing, the rotating part, is a hollow cylinder with its top fixed to the bottom of the fan unit and capable of rotating synchronously with the fan unit;

[0012] The main shaft, the stationary part, is a vertically arranged cylinder, the top end of which is inserted into the interior of the housing;

[0013] a supporting unit, surrounding the main shaft and disposed between the housing and the main shaft, for connecting the housing and the main shaft and providing support for the rotating component based on the main shaft;

[0014] The generator body is an outer rotor permanent magnet synchronous generator, comprising a generator stator fixed on the main shaft and a generator rotor fixed inside the casing, and is used to convert the mechanical energy of the rotating parts into electrical energy.

[0015] Preferably, the supporting unit comprises:

[0016] a first mechanical bearing, surrounding the main shaft and disposed between the main shaft and the lower end of the housing, wherein the inner ring and the outer ring of the first mechanical bearing are fixed to the main shaft and the housing respectively, and are used to radially and axially constrain the lower end of the housing;

[0017] A permanent magnetic bearing surrounds the main shaft and is arranged between the main shaft and the upper end of the casing. It includes an inner magnetic ring component and an outer magnetic ring component with radial magnetic field repulsion distributed along the radial direction of the main shaft. The inner magnetic ring component is sleeved on the outside of the main shaft, and the outer magnetic ring component is inserted into the interior of the casing. The radial repulsion between the inner magnetic ring component and the outer magnetic ring component provides radial support for the upper end of the casing.

[0018] Preferably, the supporting unit further comprises:

[0019] A second mechanical bearing for protecting the permanent magnetic bearing is arranged around the main shaft between the casing and the main shaft and is located above the permanent magnetic bearing. Its outer ring is fixed to the casing, and a radial protective gap is provided between the inner ring and the outer wall of the main shaft. The protective gap is smaller than the gap between the inner magnetic ring assembly and the outer magnetic ring assembly of the permanent magnetic bearing.

[0020] Preferably, the vertical axis outer rotor magnetic levitation wind turbine further comprises:

[0021] A brake protection unit comprises an electromagnet, a brake disc and a friction plate; wherein the electromagnet is sleeved and fixed on the main shaft; the brake disc and the friction plate are fixed on the casing and arranged opposite to the electromagnet; when the rotation speed of the wind turbine exceeds a threshold value, the electromagnet is supplied with current to generate electromagnetic force and adsorbs the friction plate to reduce the speed; when the rotation speed of the wind turbine is lower than the threshold value, the current supplied to the electromagnet is cut off, and the electromagnet is separated from the friction plate.

[0022] Preferably, the supporting unit further comprises:

[0023] An axial distance adjustment mechanism is used to adjust the axial relative position between the outer magnetic ring assembly and the inner magnetic ring assembly to generate an axial electromagnetic force to offset the gravity load of the rotating part, and includes a distance adjusting member and a corrugated washer; wherein, the distance adjusting member is respectively connected to the casing and the first end of the outer magnetic ring assembly, and is used to adjust and position the axial position of the first end of the outer magnetic ring assembly relative to the casing; the corrugated washer has axial elasticity, its axial first end abuts the second end of the outer magnetic ring assembly, and its axial second end is fixed to the casing, and is used to elastically support the outer magnetic ring assembly and position the axial position of its second end.

[0024] Preferably, the housing is provided with a housing lip protruding radially inward and a housing wall positioning groove recessed radially outward, and the housing lip is provided with a distance adjustment through hole;

[0025] The axial distance adjustment mechanism further includes a hole retaining ring provided inside the casing along the circumference of the casing, the outer edge of which is inserted into the casing wall positioning groove for positioning, and one axial end of which abuts against the second end of the wave washer for axial positioning of the second end of the wave washer;

[0026] The distance adjusting member is an adjusting bolt matched with the distance adjusting through hole. The adjusting bolt is inserted into each distance adjusting through hole in a threaded manner, and the bottom end thereof abuts against the first end of the outer magnetic ring assembly.

[0027] Preferably, the inner magnetic ring assembly comprises:

[0028] An axially magnetized inner magnetic ring, and an inner magnetic ring frame and an inner magnetic ring pressure ring made of non-magnetic material for fixing the inner magnetic ring; wherein, the inner magnetic ring frame is sleeved and fixed on the main shaft, and one axial end thereof is provided with an inner magnetic ring positioning portion protruding radially outward, and the inner magnetic ring is sleeved on the inner magnetic ring frame, and one axial end of the inner magnetic ring is positioned by the inner magnetic ring positioning portion, and the other end is positioned by the inner magnetic ring pressure ring sleeved on the inner magnetic ring frame.

[0029] Preferably, the outer magnetic ring assembly comprises:

[0030] An axially magnetized outer magnetic ring, and an outer magnetic ring frame and an outer magnetic ring pressure ring made of non-magnetic material for fixing the outer magnetic ring; wherein, one axial end of the outer magnetic ring frame is provided with an outer magnetic ring positioning portion protruding radially inward, and the outer magnetic ring is inserted and arranged inside the outer magnetic ring frame, one axial end of the outer magnetic ring is positioned by the outer magnetic ring positioning portion, and the other end is positioned by the outer magnetic ring pressure ring inserted into the outer magnetic ring frame.

[0031] Preferably, the fan blade unit includes:

[0032] A fan blade assembly and a vertically arranged fan blade shaft, wherein the fan blade assembly is rigidly connected to the fan blade shaft, and the fan blade assembly can drive the fan blade shaft to rotate under the action of wind; wherein, the fan blade assembly includes two identical resistance-type blades, which are installed relative to each other and horizontally staggered.

[0033] Preferably, the generator rotor is a Halbach type (a type of magnet structure) rotor.

[0034] In summary, compared with the prior art, the vertical-axis outer rotor magnetic levitation wind turbine provided by the present invention has the following beneficial effects:

[0035] 1. By adopting a hybrid support method of permanent magnetic bearings and the first mechanical bearing, and using the second mechanical bearing for auxiliary protection, the friction torque is greatly reduced while ensuring safety, and the starting wind speed is reduced to as low as 2m / s. This solves the problem of large-scale application of magnetic levitation wind turbines and is very suitable for breeze power generation applications in areas with scarce wind energy resources;

[0036] 2. The overall structure is simple. The outer and inner magnetic rings of the permanent magnetic bearing are designed with a supporting frame and are installed in the form of components, avoiding the difficulty of installing magnetic components;

[0037] 3. By installing two resistance-type blades with the same curvature relative to each other and adjusting the overlapping distance between the two blades, a higher wind energy utilization rate can be achieved;

[0038] 4. Through the design of the brake protection unit, the friction plate electromagnetic brake is energized to achieve speed-limited operation of the generator rotor, releasing the excess wind energy in windy weather through friction, thereby ensuring that the generator rotor operates within a safe range;

[0039] 5. A higher generator power density is achieved by adopting Halbach type outer rotor motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic structural diagram of a vertical-axis outer rotor magnetic levitation wind turbine according to the present invention;

[0041] Figure 2a is a schematic top view of a resistance-type blade of the present invention;

[0042] Figure 2b for Figure 2a Schematic diagram of the downward oblique view;

[0043] Figure 3a It is a structural schematic diagram of the inner magnetic ring assembly of the permanent magnetic bearing of the present invention;

[0044] Figure 3b A schematic structural diagram of the outer magnetic ring assembly of the permanent magnetic bearing of the present invention;

[0045] Figure 4 It is a structural schematic diagram of the outer magnetic ring assembly and the axial distance adjustment mechanism of the present invention;

[0046] Figure 5 This is a schematic structural diagram of the Halbach type outer rotor of the permanent magnet synchronous generator of the present invention;

[0047] Figure 6 This is a schematic structural diagram of the brake protection unit of the present invention. DETAILED DESCRIPTION

[0048] The following is a further detailed description of a vertical axis outer rotor magnetic levitation wind turbine proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will become clearer. It should be noted that the drawings are in a very simplified form and use non-precise proportions. They are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention, and are not used to limit the limiting conditions for the implementation of the present invention. Therefore, they have no technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed by the present invention without affecting the efficacy and purpose that can be achieved by the present invention.

[0049] It should be noted that, in the present invention, relational terms such as and are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include," "comprise," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or apparatus comprising a series of elements includes not only the elements explicitly listed, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0050] Combined with attachment Figures 1 to 6 The present invention provides a vertical axis outer rotor magnetic suspension wind turbine generator, as shown in the attached Figure 1 As shown, it includes: a fan blade unit, a casing 15, a main shaft 3, a support unit, a generator body and a brake protection unit; wherein,

[0051] The fan unit is a rotating component used to collect wind energy and convert it into rotational mechanical energy. It includes a fan assembly and a vertically arranged fan shaft 2. The fan assembly is rigidly connected to the fan shaft 2. The fan assembly can drive the fan shaft 2 to rotate under the action of wind. In this embodiment, as shown in the attached Figure 2a 、 2b As shown, the blade assembly includes two identical resistance blades 1, mounted opposite each other and horizontally offset. Furthermore, preferably, after installation, the horizontal overlap distance L between the two resistance blades 1 accounts for 1 / 4 of the wind turbine's rotation diameter D (the widest horizontal distance of the blade assembly). Aerodynamic analysis indicates that this design maximizes wind energy utilization. Furthermore, in this embodiment, each resistance blade 1 is secured to the blade shaft 2 via multiple horizontally arranged metal brackets 26.

[0052] The casing 15 is a rotating component, which is a hollow cylinder. The top of the casing 15 is coaxially fixed to the bottom end of the fan shaft 2 of the fan unit, and can rotate synchronously with the fan shaft 2. In some embodiments, it is assembled from an annular side wall and an upper end cover 15a and a lower end cover 15b located at both ends of the annular side wall, which is convenient for installation and maintenance. In some embodiments, the upper end cover 15a is integrally formed with the fan shaft 2, which can simplify the installation structure and increase the connection strength.

[0053] The main shaft 3 is a stationary component, which is a vertically arranged column. Its bottom end is fixed to the wind turbine mounting base (not shown) via a flange 18, and its top end is coaxially inserted into the interior of the casing 15 from the bottom of the casing 15; in the embodiment provided with a lower end cover 15b, a vertical through hole is coaxially provided on the lower end cover 15b, and the top end of the main shaft 3 is inserted into the interior of the casing 15 from the vertical through hole.

[0054] The support unit surrounds the main shaft 3 and is disposed between the housing 15 and the main shaft 3, and is used to connect the housing 15 and the main shaft 3, and to provide support for the rotating parts based on the main shaft 3; it includes:

[0055] The first mechanical bearing 8 surrounds the main shaft 3 and is arranged between the main shaft 3 and the lower end of the housing 15. Its inner and outer rings are respectively fixed to the main shaft 3 and the housing 15, and are used to radially and axially constrain the lower end of the housing 15. In the embodiment provided with a lower end cover 15b and a vertical through hole, the inner and outer rings of the first mechanical bearing 8 are respectively fixed to the outer wall of the main shaft 3 and the inner wall of the vertical through hole of the lower end cover 15b.

[0056] The permanent magnetic bearing surrounds the main shaft 3 and is arranged between the main shaft 3 and the upper end of the casing 15. It includes an inner magnetic ring component 4 and an outer magnetic ring component 5 with radial magnetic field repulsion distributed along the radial direction of the main shaft 3. The inner magnetic ring component 4 is sleeved on the outside of the main shaft 3, and the outer magnetic ring component 5 is inserted into the inside of the casing 15. The radial repulsion between the inner magnetic ring component 4 and the outer magnetic ring component 5 provides radial support for the upper end of the casing 15, thereby realizing frictionless radial suspension relative to the main shaft 3 and bearing most of the radial dynamic load when the wind turbine is working.

[0057] In some embodiments, as shown in the attached Figure 3a As shown, the inner magnetic ring assembly 4 includes: an inner magnetic ring 21 made of high-performance permanent magnet material of neodymium iron boron and axially magnetized, and an inner magnetic ring skeleton 22 and an inner magnetic ring pressure ring 20 made of non-magnetic material for fixing the inner magnetic ring 21. The inner magnetic ring 21, the inner magnetic ring skeleton 22 and the inner magnetic ring pressure ring 20 are all ring bodies; wherein, the inner magnetic ring skeleton 22 is sleeved and fixed on the main shaft 3, and one axial end thereof is provided with an inner magnetic ring positioning portion 22a protruding radially outward, and the other end is provided with an external thread 22b; the inner magnetic ring 21 is sleeved on the inner magnetic ring skeleton 22, and one axial end of the inner magnetic ring 21 is positioned by the inner magnetic ring positioning portion 22a of the inner magnetic ring skeleton 22, and the other end is positioned by the inner magnetic ring pressure ring 20 threadedly sleeved on the inner magnetic ring skeleton 22 in cooperation with the external thread 22b, thereby achieving the fixation of the inner magnetic ring 21.

[0058] As attached Figure 3bAs shown, the outer magnetic ring assembly 5 includes: an outer magnetic ring 24 made of high-performance permanent magnet material of neodymium iron boron and axially magnetized, and an outer magnetic ring skeleton 25 and an outer magnetic ring pressure ring 23 made of non-magnetic material for fixing the outer magnetic ring 24. The outer magnetic ring 24, the outer magnetic ring skeleton 25 and the outer magnetic ring pressure ring 23 are all ring bodies; wherein, one axial end of the outer magnetic ring skeleton 25 is provided with an outer magnetic ring positioning portion 25a protruding radially inward, and the other end is provided with an internal thread 25b; the outer magnetic ring 24 is inserted and arranged inside the outer magnetic ring skeleton 25, and one axial end of the outer magnetic ring 24 is positioned by the outer magnetic ring positioning portion 25a of the outer magnetic ring skeleton 25, and the other end is positioned by the outer magnetic ring pressure ring 23 inserted into the outer magnetic ring skeleton 25 by threading with the internal thread 25b, thereby achieving the fixation of the outer magnetic ring 24.

[0059] A radial permanent magnetic bearing gap is defined between the inner magnetic ring assembly 4 and the outer magnetic ring assembly 5. In this embodiment, the permanent magnetic bearing gap is approximately 1 mm. Furthermore, in some embodiments, the inner magnetic ring 21 may be constructed by axially stacking multiple individual inner magnetic rings, and the outer magnetic ring 24 may be constructed by axially stacking multiple individual outer magnetic rings that mate with each individual inner magnetic ring.

[0060] Furthermore, the present invention does not limit the specific manner in which the inner magnetic ring assembly 4 is fixed to the main shaft 3. As an example, in this embodiment, as shown in the attached Figure 3a As shown, the main shaft 3 is provided with a shaft shoulder 3a protruding radially outward and a shaft wall positioning groove 3b recessed radially inward, and the shaft shoulder 3a and the shaft wall positioning groove 3b are respectively located at the axial ends of the installation position of the inner magnetic ring assembly 4. After installation, one axial end of the inner magnetic ring assembly 4 is positioned by the shaft shoulder 3a, and the other end is positioned by the first shaft retaining ring 33 which is sleeved on the outside of the main shaft 3 and inserted into the shaft wall positioning groove 3b, thereby realizing the fixation of the inner magnetic ring assembly 4 relative to the main shaft 3.

[0061] Further, as attached Figure 4As shown, the outer magnetic ring assembly 5 is inserted into the interior of the housing 15. Preferably, in some embodiments, the permanent magnetic bearing further comprises an axial distance adjustment mechanism connected to the housing 15 and the outer magnetic ring assembly 5, for adjusting and positioning the axial position of the outer magnetic ring assembly 5. The housing 15 is provided with a shell lip 15c protruding radially inward and a shell wall positioning groove 15d recessed radially outward, and the shell lip 15c and the shell wall positioning groove 15d are respectively located at the upper and lower ends of the installation position of the outer magnetic ring assembly 5. The shell lip 15c is provided with a plurality of distance adjustment holes evenly distributed along the circumference, for example, 4 distance adjustment holes distributed at intervals of 90°; the axial distance adjustment mechanism comprises an adjustment bolt 12, a wave washer 13 and a hole retaining ring 14 arranged in sequence from top to bottom; wherein, the number and specifications of the adjustment bolt 12 are related to the adjustment The outer magnetic ring assembly 5 is adapted to the distance through-holes, and each adjusting bolt 12 is threadedly inserted into each distance adjustment through-hole, and its bottom end abuts the top of the outer magnetic ring assembly 5; the wave washer 13 is elastic, and its top abuts the bottom of the outer magnetic ring assembly 5, used to support the outer magnetic ring assembly 5, and can be compressed and restored in the axial direction under the action of external force; the hole retaining ring 14 is arranged inside the housing 15 along the circumference of the housing 15, and its outer edge is inserted into the housing wall positioning groove 15d for positioning, and its top abuts the bottom of the wave washer 13, used to position the bottom of the wave washer 13. The axial distance adjustment mechanism can also take other forms, such as being arranged in reverse up and down, for example, adopting other distance adjustment methods in the existing technology, etc. Its working principle is to push the outer magnetic ring assembly 5 to axially compress or release the wave washer 13 by screwing in or out each adjusting bolt 12 with the same amplitude, thereby adjusting the axial relative position between the outer magnetic ring assembly 5 and the inner magnetic ring assembly 4, and then generating an axial electromagnetic force between the outer magnetic ring assembly 5 and the inner magnetic ring assembly 4 to offset the gravity load of the rotating part of the wind turbine and reduce the gravity load of the first mechanical bearing 8 thereunder.

[0062] Furthermore, in order to protect the permanent magnetic bearing and avoid the outer magnetic ring assembly 5 and the inner magnetic ring assembly 4 from colliding and being damaged, the support unit further includes a second mechanical bearing 11. Figure 1 As shown, the second mechanical bearing 11 surrounds the main shaft 3 and is disposed between the housing 15 and the main shaft 3, above the permanent magnetic bearing. Its outer ring is fixed to the inner edge of the housing lip 15c of the housing 15, and a radial protective gap is defined between its inner ring and the outer wall of the main shaft 3. This protective gap is smaller than the permanent magnetic bearing gap. In this embodiment, the protective gap is half the permanent magnetic bearing gap, approximately 0.5 mm. When the outer magnetic ring assembly 5 and the inner magnetic ring assembly 4 of the permanent magnetic bearing come into radial proximity, the inner ring of the second mechanical bearing 11 first contacts the outer wall of the main shaft 3, preventing the outer magnetic ring assembly 5 and the inner magnetic ring assembly 4 from colliding and being damaged. After contact, the housing 15 can drive the outer ring of the second mechanical bearing 11 to rotate relative to its inner ring and the main shaft 3, without affecting the normal operation of the wind turbine or damaging any components.

[0063] The generator body is an outer rotor permanent magnet synchronous generator, which is used to convert the mechanical energy of the rotating parts into electrical energy; its axial position is located between the permanent magnet bearing and the first mechanical bearing 8, so that the center of gravity of the wind turbine is low and has good stability; it includes a generator stator 6 located on the inner ring and a generator rotor 7 located on the outer ring, wherein the generator stator 6 is sleeved and fixed on the main shaft 3, and a center hole is provided inside the main shaft 3. The lead wire 17 of the generator stator 6 is led out through the center hole of the main shaft 3 and connected to the load (not shown); the generator rotor 7 is fixed inside the casing 15 and adopts a Halbach type (Halbach, a magnetic structure) rotor, as shown in the attached figure. Figure 5 As shown, the structural feature of this type of rotor is that it does not require a magnetizer. It is composed of 60 magnetic steels 19 to form a ring, with each 5 magnetic steels 19 forming a group. The magnetization direction of each group in the clockwise direction circulates in the order of radially outward → circumferentially clockwise → radially inward → circumferentially counterclockwise → radially outward, so that a complete closed magnetic circuit can be formed through each magnetic steel 19. Since the magnetizer is omitted, the mass of the generator body is greatly reduced, and the number of parts of the generator body is reduced, and the structure is simplified.

[0064] Brake protection unit is an electromagnetic brake, as shown in the attached Figure 6As shown, it includes an electromagnet 10 connected to the stationary component, and a brake disc 9 and friction plate 29 connected to the rotating component. Specifically, the electromagnet 10 is an axially mounted ring that is sleeved on the main shaft 3. The inner hole of the electromagnet 10 and the outer wall of the main shaft 3 are respectively provided with keyways (not shown). The electromagnet 10 is fixed by the engagement of a key 31 with the keyway. At the same time, the electromagnet 10 is axially positioned at the bottom by a second shaft retaining ring 32 located below it and sleeved on the outside of the main shaft 3. The electromagnet 10 includes an internal conductive coil 30, the wire of which is led through the center hole of the main shaft 3 to the control circuit (not shown). The brake disc 9 and friction plate 29 are also rings. The brake disc 9 is fixed to the lower end cover 15b by screws 28, and the friction plate 29 is installed at the bottom of the brake disc 9. The working principle of the brake protection unit is as follows: when the rotation speed of the wind turbine exceeds a preset threshold, the control circuit supplies current to the conductive coil 30 of the electromagnet 10, causing the electromagnet 10 to generate electromagnetic force and move upward to contact the friction plate 29. As the friction plate 29 rotates with the rotating part of the wind turbine, the friction resistance between it and the electromagnet 10 increases, thereby reducing the rotation speed of the rotating part. When the rotation speed of the wind turbine falls below the threshold, the current in the conductive coil 30 of the electromagnet 10 is cut off, the electromagnetic force disappears, and the electromagnet 10 separates from the friction plate 29 due to gravity, and the speed of the wind turbine gradually increases. The brake protection unit can adjust the power supply state of the conductive coil 30 of the electromagnet 10 in real time according to the change in the rotation speed of the wind turbine, thereby controlling the separation and contact between the electromagnet 10 and the friction plate 29, thereby achieving speed-limiting brake protection for the wind turbine. Since it only limits the speed but does not stop the wind turbine, light wind power generation can still be carried out when the brake protection unit is working, adapting to harsh working conditions.

[0065] The operating principle of the present invention is as follows: the main shaft 3 of the wind turbine is the stationary component, while the blade unit and housing 15, which serve as the rotating components, are mounted on the exterior of the main shaft 3. Natural wind flow generates different thrusts on the two sides of the blade unit, generating a rotational torque on the rotating component relative to the stationary component. When the rotational torque exceeds the resistance torque, the rotating component drives the generator rotor 7 to begin rotating, thereby converting wind energy into rotational mechanical energy. As wind speed increases, the rotation speed of the generator rotor 7 accelerates. Through electromagnetic induction between the generator stator 6 and the generator rotor 7, the rotational mechanical energy is converted into electrical energy in the coils of the generator stator 6 and ultimately output to the load via the lead wire 17. If the rotation speed of the generator rotor 7 continues to increase beyond the set safe speed, the brake protection unit activates, increasing the resistance torque by increasing the braking torque of the electromagnetic brake, thereby decelerating the generator rotor 7, maintaining the rotation speed of the generator rotor 7 within the safe speed range and enabling dynamic adjustment.

[0066] In summary, the present invention provides a vertical axis outer rotor magnetic levitation wind turbine, which adopts a hybrid support method of permanent magnetic bearings and first mechanical bearings, and assists with the protection of the second mechanical bearing. Under the premise of ensuring safety, the friction torque is greatly reduced and the starting wind speed is reduced. The starting wind speed can be as low as 2m / s, which solves the problem of large-scale application of magnetic levitation wind turbines and is very suitable for breeze power generation applications in areas with scarce wind energy resources; the overall structure is simple, and the outer magnetic ring and inner magnetic ring of the permanent magnetic bearing are designed with a support skeleton and installed in the form of components to avoid the difficulty of installing magnetic components; by relatively installing two resistance-type blades with the same curvature and adjusting the overlapping distance between the two blades, it is ensured that a high wind energy utilization rate can be achieved; through the design of the brake protection unit, the speed limit operation of the generator rotor is achieved by energizing the friction plate electromagnetic brake, and the excess wind energy in windy weather is released through friction, thereby ensuring that the generator rotor operates within a safe range; by adopting the Halbach type outer rotor motor, the power density of the generator is relatively high.

[0067] The contents not described in detail in the present invention belong to the prior art known to professionals in this field. The present invention is widely used in cities, remote rural areas, islands and other areas with scarce wind resources to generate electricity using breeze.

[0068] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description is not intended to limit the present invention. After reading the above description, various modifications and substitutions of the present invention will become apparent to those skilled in the art. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A vertical axis outer rotor magnetic levitation wind turbine, characterized in that: include: The wind blade unit is a rotating component used to collect wind energy and convert it into rotational mechanical energy; The housing, the rotating part, is a hollow cylinder with its top fixed to the bottom of the fan unit and capable of rotating synchronously with the fan unit; The main shaft, the stationary part, is a vertically arranged cylinder, the top end of which is inserted into the interior of the housing; a supporting unit, surrounding the main shaft and disposed between the housing and the main shaft, for connecting the housing and the main shaft and providing support for the rotating component based on the main shaft; The generator body is an outer rotor permanent magnet synchronous generator, comprising a generator stator fixed on the main shaft and a generator rotor fixed inside the casing, and is used to convert the mechanical energy of the rotating parts into electrical energy; Wherein, the supporting unit comprises: a first mechanical bearing, surrounding the main shaft and disposed between the main shaft and the lower end of the housing, wherein the inner ring and the outer ring of the first mechanical bearing are fixed to the main shaft and the housing respectively, and are used to radially and axially constrain the lower end of the housing; a permanent magnetic bearing, surrounding the main shaft and disposed between the main shaft and the upper end of the housing, comprising an inner magnetic ring assembly and an outer magnetic ring assembly distributed radially along the main shaft and having a radial magnetic field repulsion force, the inner magnetic ring assembly being sleeved on the outside of the main shaft, and the outer magnetic ring assembly being inserted into the interior of the housing, and providing radial support for the upper end of the housing through the radial repulsion between the inner and outer magnetic ring assemblies; a second mechanical bearing for protecting the permanent magnetic bearing, surrounding the main shaft and disposed between the housing and the main shaft, and located above the permanent magnetic bearing, with its outer ring fixed to the housing and a radial protective gap between its inner ring and the outer wall of the main shaft, wherein the protective gap is smaller than the gap between the inner magnetic ring assembly and the outer magnetic ring assembly of the permanent magnetic bearing; An axial distance adjustment mechanism is used to adjust the axial relative position between the outer magnetic ring assembly and the inner magnetic ring assembly to generate an axial electromagnetic force to offset the gravity load of the rotating part, and includes a distance adjusting member and a corrugated washer; wherein, the distance adjusting member is respectively connected to the casing and the first end of the outer magnetic ring assembly, and is used to adjust and position the axial position of the first end of the outer magnetic ring assembly relative to the casing; the corrugated washer has axial elasticity, its axial first end abuts the second end of the outer magnetic ring assembly, and its axial second end is fixed to the casing, and is used to elastically support the outer magnetic ring assembly and position the axial position of its second end.

2. The vertical axis outer rotor magnetic levitation wind turbine according to claim 1, characterized in that: Also includes: A brake protection unit comprises an electromagnet, a brake disc and a friction plate; wherein the electromagnet is sleeved and fixed on the main shaft; the brake disc and the friction plate are fixed on the casing and arranged opposite to the electromagnet; when the rotation speed of the wind turbine exceeds a threshold value, the electromagnet is supplied with current to generate electromagnetic force and adsorbs the friction plate to reduce the speed; when the rotation speed of the wind turbine is lower than the threshold value, the current supplied to the electromagnet is cut off, and the electromagnet is separated from the friction plate.

3. The vertical axis outer rotor magnetic levitation wind turbine according to claim 1, characterized in that: The housing is provided with a housing lip protruding radially inward and a housing wall positioning groove recessed radially outward, and the housing lip is provided with a distance adjustment through hole; The axial distance adjustment mechanism further includes a hole retaining ring provided inside the casing along the circumference of the casing, the outer edge of which is inserted into the casing wall positioning groove for positioning, and one axial end of which abuts against the second end of the wave washer for axial positioning of the second end of the wave washer; The distance adjusting member is an adjusting bolt matched with the distance adjusting through hole. The adjusting bolt is inserted into each distance adjusting through hole in a threaded manner, and the bottom end thereof abuts against the first end of the outer magnetic ring assembly.

4. The vertical axis outer rotor magnetic levitation wind turbine according to claim 1, characterized in that: The inner magnetic ring assembly comprises: An axially magnetized inner magnetic ring, and an inner magnetic ring frame and an inner magnetic ring pressure ring made of non-magnetic material for fixing the inner magnetic ring; wherein, the inner magnetic ring frame is sleeved and fixed on the main shaft, and one axial end thereof is provided with an inner magnetic ring positioning portion protruding radially outward, and the inner magnetic ring is sleeved on the inner magnetic ring frame, and one axial end of the inner magnetic ring is positioned by the inner magnetic ring positioning portion, and the other end is positioned by the inner magnetic ring pressure ring sleeved on the inner magnetic ring frame.

5. The vertical axis outer rotor magnetic levitation wind turbine according to claim 4, characterized in that: The outer magnetic ring assembly comprises: An axially magnetized outer magnetic ring, and an outer magnetic ring frame and an outer magnetic ring pressure ring made of non-magnetic material for fixing the outer magnetic ring; wherein, one axial end of the outer magnetic ring frame is provided with an outer magnetic ring positioning portion protruding radially inward, and the outer magnetic ring is inserted and arranged inside the outer magnetic ring frame, one axial end of the outer magnetic ring is positioned by the outer magnetic ring positioning portion, and the other end is positioned by the outer magnetic ring pressure ring inserted into the outer magnetic ring frame.

6. The vertical axis outer rotor magnetic levitation wind turbine according to claim 1, characterized in that: The fan blade unit includes: A fan blade assembly and a vertically arranged fan blade shaft, wherein the fan blade assembly is rigidly connected to the fan blade shaft, and the fan blade assembly can drive the fan blade shaft to rotate under the action of wind; wherein, the fan blade assembly includes two identical resistance-type blades, which are installed relative to each other and horizontally staggered.

7. The vertical axis outer rotor magnetic levitation wind turbine according to claim 1, characterized in that: The generator rotor is a Halbach type rotor.

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