A tangential rotor lamination and rotor structure

Abstract

The application discloses a tangential rotor lamination and a rotor structure, and relates to the technical field of permanent magnet motors. The rotor lamination comprises a magnetic isolation hole, which is arranged on a lamination body and has an opening at the bottom; a stainless steel key is arranged in the magnetic isolation hole and above the opening; a first magnetic isolation bridge is arranged on both sides of the magnetic isolation hole and has a structure of being wide at the top and narrow at the bottom; a second magnetic isolation bridge is arranged on both sides of the magnetic isolation hole and connected with the bottom of the corresponding first magnetic isolation bridge, and the cross section of the second magnetic isolation bridge is in a strip shape; a third magnetic isolation bridge is arranged on both sides of the magnetic isolation hole and connected with the bottom of the corresponding second magnetic isolation bridge, and the cross section of the third magnetic isolation bridge is in a strip shape; and a bearing table extending outward is formed between the second magnetic isolation bridge and the third magnetic isolation bridge. In combination with reasonable size design of the magnetic isolation hole and the surrounding structure, the magnetic resistance of the key region is increased and the magnetic circuit distribution is optimized according to the magnetic resistance regulation principle, the magnetic flux passing through the air closed is significantly reduced, and the inter-pole leakage magnetic is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet motor technology, specifically to a tangential rotor lamination and rotor structure. Background Technology

[0002] As a highly efficient and energy-saving power device, the performance of a permanent magnet motor is directly affected by the rationality of its rotor structure. According to rotor structure, permanent magnet motors mainly include straight-line, V-shaped, and tangential types. Among them, tangential permanent magnet motors, because the magnetic flux per pole is provided by two adjacent magnets, have a significant magnetic focusing effect. They not only have high magnet utilization but also a simple overall structure, thus finding wide application in many industrial fields such as wind power generation, new energy vehicle drives, coal mining machinery, and metallurgical equipment.

[0003] In tangential rotor design, reducing magnet leakage and improving magnet utilization are among the core technical objectives. Existing technologies typically achieve this by using magnetic shielding bridges or magnetic shielding aluminum rings. While magnetic shielding aluminum rings can achieve some magnetic shielding, this structure has significant drawbacks: firstly, the addition of the magnetic shielding aluminum ring complicates the overall rotor structure; secondly, the magnetic shielding aluminum ring requires extremely high machining precision, significantly increasing the difficulty of assembling and fitting the magnets, magnetic shielding aluminum ring, and rotor support, which is detrimental to industrial production, installation, and maintenance.

[0004] Another mainstream approach is to reduce magnetic leakage by using a magnetic isolation bridge. However, the existing magnetic isolation bridge design for tangential rotor laminations has a key technical shortcoming. Although the magnetic isolation bridge can reduce some inter-pole magnetic leakage, its structural design fails to effectively block the closed path of the magnetic lines of force in the lower half of the magnet. A large number of magnetic lines of force can still form a closed loop through the magnetic isolation bridge, resulting in an unsatisfactory magnetic isolation effect. This magnetic leakage phenomenon means that the magnetic lines of force generated by the magnet cannot fully participate in the electromagnetic energy conversion of the motor, resulting in low magnet utilization and severely restricting further improvement of the performance of tangential permanent magnet motors. Summary of the Invention

[0005] This invention proposes a tangential rotor lamination and rotor structure to reduce inter-pole leakage magnetic flux. Its purpose is to solve the problems of difficult installation, complex structure, poor magnetic isolation effect of magnetic bridge, and low utilization rate of magnets in existing tangential rotor laminations and rotor structures.

[0006] To achieve the above objectives, the technical solution of this application is: a tangential rotor lamination, which has a modular single-pole structure, specifically comprising:

[0007] A magnetic shielding hole is provided on the lamination body and has an opening at the bottom;

[0008] The stainless steel key is located inside the magnetic shielding hole, above the opening.

[0009] The first magnetic isolation bridge is located on both sides of the magnetic isolation hole and has a structure that is wider at the top and narrower at the bottom.

[0010] The second magnetic isolation bridge is set on both sides of the magnetic isolation hole and connected to the bottom of the corresponding first magnetic isolation bridge. Its cross-section is a long strip structure.

[0011] The third magnetic isolation bridge is located on both sides of the magnetic isolation hole and is connected to the bottom of the corresponding second magnetic isolation bridge. Its cross-section is a long strip structure, and an outwardly extending support platform is formed between the second and third magnetic isolation bridges.

[0012] In a preferred embodiment of the present invention, the length of the second magnetic isolation bridge is a, and the vertical distance between the top edge of the magnetic isolation hole and the extension line of the bottom edge of the second magnetic isolation bridge is b, wherein the dimension of a is 1 / 3 to 3 / 4 of the dimension of b.

[0013] As a preferred embodiment of the present invention, the angle between the inclined side of the first magnetic bridge and the outer edge of the adjacent lamination body is β°, and the value is 45°≤β°<70°.

[0014] As a preferred embodiment of the present invention, the width of the outwardly extending support platform is 2-3 mm.

[0015] As a preferred embodiment of the present invention, the stainless steel key is provided with a plurality of bolt holes, the size of which is 2mm to 4mm larger than the bolt holes.

[0016] The present invention also provides a rotor structure, including a rotor support, 2p tangential rotor laminations evenly distributed in the circumferential direction, where p is the number of pole pairs; magnetic slots are provided between adjacent tangential rotor laminations, and permanent magnets are located in the magnetic slots; the rotor support is provided with grooves for fixing the tangential rotor laminations, and the number of grooves is 2p.

[0017] As a preferred embodiment of the present invention, the angle between the outer inclined side of the third magnetic bridge and the center line of the magnetic steel groove is α°, where 10°≤α°<20°.

[0018] As a preferred embodiment of the present invention, a disconnected magnetic bridge is formed between the tops of adjacent tangential rotor laminations, and the width of the disconnected magnetic bridge is 4 to 8 mm smaller than the width of the permanent magnet.

[0019] As a preferred embodiment of the present invention, the dimension of b is 18% to 22% of the width of the permanent magnet.

[0020] In a preferred embodiment of the present invention, the permanent magnet is placed on a support platform.

[0021] By adopting the above technical solution, the present invention can achieve the following technical effects:

[0022] 1. By optimizing the magnetic isolation bridge structure of existing tangential rotors through targeted design of magnetic isolation holes, the closed path of leakage flux through the magnetic isolation bridge can be effectively blocked. Combined with the rational dimensional design of the magnetic isolation holes and surrounding structures, and based on the principle of reluctance control, the magnetic reluctance in key areas is increased and the magnetic circuit distribution is optimized, significantly reducing the magnetic flux leakage through the closed air path, thereby greatly reducing inter-pole leakage flux. Compared with existing magnetic isolation bridge technology, this invention can reduce inter-pole leakage flux by up to 37.5%, and increase the back EMF by 27V in a 380V motor, an improvement of 7.91%, effectively solving the core problems of poor magnetic isolation effect and low magnet utilization in existing technologies.

[0023] 2. This invention eliminates the magnetic shielding aluminum ring in the traditional structure. By optimizing the rotor lamination structure and the cooperation of stainless steel keys, reliable magnetic shielding and fixation are achieved. This avoids the problems caused by the magnetic shielding aluminum ring, such as the complex rotor structure, high processing precision requirements, and difficulty in assembling the magnets, magnetic shielding aluminum ring and rotor support. It significantly simplifies the overall structure and reduces the difficulty of installation and production complexity.

[0024] 3. The rotor laminations adopt a modular single-pole structure, with 2p (p being the number of pole pairs) single-pole laminations spliced ​​together to form a complete circle in the circumferential direction. This design can be matched with single-slot stamping die processing, reducing die development costs and complexity. Moreover, the single-pole structure has a simple manufacturing process and a short production cycle, which can effectively improve production efficiency and meet the needs of mass production. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the rotor structure of the present invention;

[0027] Figure 2 This is a partially enlarged schematic diagram of the rotor structure of the present invention;

[0028] Figure 3 This is a schematic diagram of two adjacent rotor laminations of the present invention;

[0029] Figure 4 This is a schematic diagram of two adjacent rotor laminations of the present invention;

[0030] Figure 5 This is a schematic diagram of the rotor sector lamination principle in the prior art.

[0031] Figure 6 This is a simulation cloud diagram of the unloaded magnetic field lines of the present invention;

[0032] Figure 7 Simulation cloud diagram of unloaded magnetic field lines for existing technologies;

[0033] Figure 8 This is a comparison curve of the back EMF of the unloaded line in the present invention and the prior art;

[0034] The numbers in the diagram are explained as follows: 1. Tangential rotor lamination, 2. Permanent magnet, 3. Rotor support, 4. Stainless steel key, 5. Disconnectable magnetic isolation bridge, 6. Magnet slot, 7. Bolt hole, 8. Magnetic isolation hole, 9. Opening, 10. First magnetic isolation bridge, 11. Second magnetic isolation bridge, 12. Third magnetic isolation bridge, 13. Existing magnetic slot, 14. Lower magnetic isolation bridge, 15. Existing magnetic isolation hole, 16. Upper magnetic isolation bridge. Detailed Implementation

[0035] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0038] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0039] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0040] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0041] It should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0042] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0043] Example 1:

[0044] This embodiment provides a tangential rotor lamination, which has a modular single-pole structure, as follows:

[0045] The lamination body has magnetic isolation holes and bolt holes. The bottom of the magnetic isolation holes has an opening, and a hexagonal hole is formed by the first, second, and third magnetic isolation bridges. The air gap blocks the closed path of leakage magnetic flux. The lamination body can be made of several 0.5mm or 0.35mm thick silicon steel sheets stacked together. Bolts are used to axially fix the silicon steel sheets into a whole through the bolt holes, preventing the iron core from loosening or shifting due to vibration, centrifugal force, or electromagnetic force during motor operation, thus ensuring the stability of the iron core structure.

[0046] The stainless steel key is set inside the magnetic isolation hole and above the opening, and has several bolt holes arranged along the axial direction. The opening size of the magnetic isolation hole is 2mm to 4mm larger than the bolt holes on the stainless steel key to ensure that the bolts can be smoothly inserted and to achieve a fixed connection between the lamination body and the rotor support.

[0047] The first magnetic isolation bridge is symmetrically arranged on both sides of the magnetic isolation hole, with a structure that is wider at the top and narrower at the bottom. The angle between its hypotenuse and the outer edge of the adjacent lamination body is β°, and the value satisfies 45°≤β°<70°. This structure makes the magnetic reluctance of the lower part of the magnetic isolation bridge large and the magnetic reluctance of the upper part small, effectively reducing the leakage flux in the lower region of the magnet.

[0048] The second magnetic isolation bridge is symmetrically arranged on both sides of the magnetic isolation hole and connected to the bottom of the corresponding first magnetic isolation bridge. It has a long strip-shaped cross-section. The length of the second magnetic isolation bridge is 'a', and the vertical distance between the top edge of the magnetic isolation hole and the extended line of the bottom edge of the second magnetic isolation bridge is 'b'. The dimension of 'a' is 1 / 3 to 3 / 4 of the dimension of 'b', which ensures structural strength while optimizing magnetic reluctance distribution.

[0049] The third magnetic isolation bridge is symmetrically arranged on both sides of the magnetic isolation hole and connected to the bottom of the corresponding second magnetic isolation bridge. It has a long strip structure in cross section. An outwardly extending support platform is formed between the second and third magnetic isolation bridges. The width of the support platform is 2-3 mm, which is used to support the permanent magnet.

[0050] In this embodiment, the thickness of the second magnetic isolation bridge, the third magnetic isolation bridge, and the support platform is all c. The dimension of c should be as small as possible while meeting the strength requirements.

[0051] Example 2:

[0052] like Figure 1-4 As shown, this embodiment discloses a rotor structure based on the above-mentioned tangential rotor laminations. The specific structure is as follows: The rotor structure includes a rotor support, 2p tangential rotor laminations (p is the number of pole pairs) evenly distributed in the circumferential direction as described in Embodiment 1, permanent magnets, and stainless steel keys.

[0053] The rotor support is provided with grooves for fixing tangential rotor laminations. The grooves are trapezoidal or dovetail grooves, and there are 2p grooves in total. They are assembled one-to-one with the rotor laminations to ensure reliable circumferential positioning of the laminations.

[0054] A magnetic slot is provided between adjacent tangential rotor laminations. The permanent magnet is located in the magnetic slot and sits on the support platform between the second and third magnetic isolation bridges to ensure that the permanent magnet is installed stably.

[0055] In this preferred embodiment, the angle between the outer inclined side of the third magnetic bridge and the center line of the magnet slot is α°, with a value satisfying 10°≤α°<20°. By increasing the magnetic resistance of the closed air flux path between adjacent laminations, leakage magnetic flux in the magnetic bridge area is reduced. By limiting the angles α° and β°, it is ensured that the magnetic isolation hole has sufficient size to accommodate the stainless steel key, and by increasing the distance between the magnetic bridges on adjacent rotor laminations, the path of leakage magnetic flux through the closed air is lengthened, thereby increasing the magnetic resistance in this area and effectively reducing leakage magnetic flux on the third magnetic bridge.

[0056] As a preferred embodiment provided in this example, a disconnected magnetic bridge is formed between the tops of adjacent tangential rotor laminations. Its width is 4-8 mm smaller than the width of the permanent magnet, balancing magnetic shielding effect and structural strength. The disconnected magnetic bridge, with its disconnected design, combined with the unipolar modular structure of the rotor laminations, allows for processing using single-slot stamping dies. This design not only simplifies the structure but also shortens the production cycle, facilitating mass production.

[0057] As a preferred embodiment provided in this example, the relevant dimension b of the magnetic isolation hole (the vertical distance between the top edge of the magnetic isolation hole and the extension line of the bottom edge of the second magnetic isolation bridge) is taken as 18% to 22% of the width of the permanent magnet, which further optimizes the magnetic circuit distribution and reduces inter-pole magnetic leakage.

[0058] like Figure 5 As shown, the rotor sector lamination of the prior art has a partially closed magnetic isolation hole and lower magnetic isolation bridges on both sides of the magnetic isolation hole; the top of the magnetic steel slot of the prior art has an upper magnetic isolation bridge.

[0059] like Figure 6-7 As shown, under the same simulation conditions, when the total number of magnetic field lines is 50, the number of leakage magnetic field lines in the lower half of the magnet closed through the magnetic isolation hole is 5; while the number of leakage magnetic field lines in the lower half of the magnet closed through the lower magnetic isolation bridge 14 is 8. Therefore, the inter-pole leakage magnetic field of this invention is reduced by 37.5%, significantly improving the utilization rate of the magnet.

[0060] like Figure 8 As shown, the upper magnetic bridge 16 can be designed to be closed or open. With the amount of magnets and the electromagnetic scheme remaining unchanged, taking a 380V motor as the research object, the influence of the rotor lamination structure of this invention on the no-load back EMF is compared only with that of the prior art: compared with the existing technology where the upper magnetic bridge is closed, the no-load back EMF of this invention is increased by 27V, an increase of 7.91%; compared with the existing technology where the upper magnetic bridge is open, the no-load back EMF of this invention is increased by 16V, an increase of 4.54%.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A tangential rotor lamination, having a modular single-pole structure, characterized in that, include: A magnetic shielding hole is provided on the lamination body and has an opening at the bottom; The stainless steel key is located inside the magnetic shielding hole, above the opening. The first magnetic isolation bridge is located on both sides of the magnetic isolation hole and has a structure that is wider at the top and narrower at the bottom. The second magnetic isolation bridge is set on both sides of the magnetic isolation hole and connected to the bottom of the corresponding first magnetic isolation bridge. Its cross-section is a long strip structure. The third magnetic isolation bridge is set on both sides of the magnetic isolation hole and connected to the bottom of the corresponding second magnetic isolation bridge. Its cross-section is a long strip structure, and an outwardly extending support platform is formed between the second and third magnetic isolation bridges. The length of the second magnetic isolation bridge is a, and the vertical distance between the top edge of the magnetic isolation hole and the extension line of the bottom edge of the second magnetic isolation bridge is b, where the dimension of a is 1 / 3 to 3 / 4 of the dimension of b; The angle between the hypotenuse of the first magnetic bridge and the outer edge of the adjacent lamination body is β°, with a value of 45°≤β°<70°; The width of the outward-extending support platform is 2~3mm.

2. The tangential rotor lamination according to claim 1, characterized in that, The stainless steel key is provided with several bolt holes, and the opening size is 2mm~4mm larger than the bolt hole.

3. A rotor structure, characterized in that, The rotor includes a rotor support and 2p tangential rotor laminations as described in any one of claims 1-2, evenly distributed in the circumferential direction, where p is the number of pole pairs; magnetic slots are provided between adjacent tangential rotor laminations, and permanent magnets are located in the magnetic slots; the rotor support is provided with grooves for fixing the tangential rotor laminations, and the number of grooves is 2p.

4. The rotor structure according to claim 3, characterized in that, The angle between the outer inclined side of the third magnetic bridge and the center line of the magnetic steel groove is α°, where 10°≤α°<20°.

5. The rotor structure according to claim 3, characterized in that, The top of adjacent tangential rotor laminations is a disconnected magnetic bridge, the width of which is 4-8 mm smaller than the width of the permanent magnet.

6. The rotor structure according to claim 3, characterized in that, The value of b is 18% to 22% of the width of the permanent magnet.

7. The rotor structure according to claim 3, characterized in that, The permanent magnet sits on the support platform.

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