Special-shaped magnetic barrier punching sheet segmented symmetrical laminated rotor, preparation method and motor

Abstract

The invention discloses a special-shaped magnetic barrier punching sheet segmented symmetrical laminated rotor, a preparation method and a motor, the rotor comprises a plurality of rotor bodies, one rotor body comprises a plurality of layers of rotor iron cores, the rotor iron cores are assembled by splicing a plurality of iron core punching sheets, N groups of through grooves with the same shape and size are uniformly arranged on the iron core punching sheets, and permanent magnets are arranged in the through grooves; and the plurality of anisotropic magnetic barrier groups are arranged on one side, far away from the circle center of the iron core punching sheet, of the plurality of through grooves. According to the invention, magnetic field distribution in the motor is optimized by using the anisotropic magnetic barrier holes with special shapes, so that energy loss can be reduced while the efficiency and the performance of the motor are improved; the rotor iron cores or the anisotropic magnetic barrier holes are divided into a plurality of parts to adapt to different magnetic field requirements and mechanical design requirements, the overall performance and reliability of the motor can be improved, and meanwhile, the symmetrical arrangement of the rotor iron cores can ensure that the motor is kept balanced in the operation process, vibration and noise are reduced, and the operation stability is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of permanent magnet motors, and in particular relates to a segmented symmetrical stacked rotor with special-shaped magnetic barrier punching sheets, a preparation method and a motor. Background Art

[0002] A permanent magnet synchronous motor (IPM) is a motor that places a layer of permanent magnets on the inside of the rotor and mainly uses permanent magnet torque and reluctance torque as an auxiliary.

[0003] Shaped magnetic barrier sheet: refers to magnetic materials with specific shapes used in motors or generators. The electromagnetic performance of the equipment is improved by optimizing its shape and arrangement. This material can control the current by changing the magnetic field, achieving more efficient energy conversion.

[0004] Segmented symmetrical stacked rotor: The rotor is an important part of the motor, and its design directly affects the performance of the motor. Segmented symmetrical stacked rotor means that the rotor is divided into multiple segments, each with the same design, but the combination and superposition of the segments can effectively improve the magnetic flux density and rotation stability of the rotor.

[0005] In traditional motor design, the rotor structure is often uniform, which can easily lead to uneven magnetic field distribution and affect the motor's operating efficiency and output power. Summary of the invention

[0006] The present invention aims at solving the problems in the prior art and proposes the following technical solutions:

[0007] The rotor with special-shaped magnetic barrier punching is segmented and symmetrically stacked, including:

[0008] A plurality of rotor bodies, one of the rotor bodies comprising a multi-layer rotor core, the rotor core being assembled by splicing a plurality of core punching sheets, the core punching sheets being evenly provided with N groups of through slots of the same shape and size, the through slots being provided with permanent magnets;

[0009] A plurality of anisotropic magnetic barrier groups are provided on one side of a plurality of through slots away from the center of a core punching sheet, the anisotropic magnetic barrier groups include a group of anisotropic magnetic barrier holes spaced apart along the d-axis direction of the core punching sheet, the number of the anisotropic magnetic barrier holes in a group is set to M, the M anisotropic magnetic barrier holes are spaced apart along the extension direction of the slot wall of the through slot, and a magnetic conductive channel 1 is formed between any two adjacent anisotropic magnetic barrier holes in a group.

[0010] As a preferred embodiment of the above technical solution, the width of the magnetic conductive channel 1 is a1, and the distance between the two ends of a group of the anisotropic magnetic barrier holes is A, satisfying 1 / 6≦a1 / A≦4 / 3.

[0011] As a preferred embodiment of the above technical solution, the shortest distances between one through slot and two adjacent through slots are C1 and C2 respectively, the height of the permanent magnet is B1, and the shortest distance between two adjacent through slots is C2=kB1BrC1 / Bs, wherein k is an empirical coefficient, k≦0.5, Br is the remanent magnetism of the permanent magnet, and Bs is the saturation magnetic flux density of the silicon steel sheet.

[0012] As a preferred embodiment of the above technical solution, a magnetic bridge is provided between the end of the through slot and the edge of the core punching sheet, and the distance Brib between the end of the through slot and the edge of the core punching sheet satisfies 0.5≦Brib.

[0013] As a preferred embodiment of the above technical solution, the thickness of the permanent magnet in the d-axis direction of the core punching sheet is B2, the anisotropic magnetic barrier hole has a magnetic barrier hole side wall one and a magnetic barrier hole side wall two that are relatively arranged, and the distance from the magnetic barrier hole side wall one to the magnetic barrier hole side wall two is the thickness a2 of the anisotropic magnetic barrier hole, B2>a2.

[0014] As a preferred embodiment of the above technical solution, the thickness of the middle portion of the permanent magnet is greater than the thickness at both ends.

[0015] As a preferred embodiment of the above technical solution, gaps are provided at both ends of the permanent magnet and both ends of the through slot, and the gaps are used to be filled with non-magnetic conductive media.

[0016] The present invention also includes a method for preparing a rotor with segmented symmetrical stacking of special-shaped magnetic barrier punching sheets, the method comprising the following steps:

[0017] S1. Punching sheet segmentation: Use cold-rolled silicon steel to process into a predetermined shape of core punching sheet through a stamping die, and then segment it, and apply a layer of insulating paint on the surface;

[0018] S2. Magnetic barrier design: through slots and anisotropic magnetic barrier groups are set on the stamped core sheets, and permanent magnets are embedded in the through slots;

[0019] S3, punching sheet assembly: assemble multiple iron core punching sheets into a complete rotor iron core, then stack and sleeve the multiple complete rotor iron cores on the rotating shaft, and finally fix the multiple complete punching sheets on the rotating shaft by two rotor fans.

[0020] According to one aspect of the present invention, the present invention also includes a motor, comprising:

[0021] The above-mentioned rotor is symmetrically stacked in sections with special-shaped magnetic barrier punchings; and

[0022] The motor stator is sleeved on the circumference of the rotor.

[0023] The beneficial effects of the present invention are:

[0024] 1. The present invention optimizes the magnetic field distribution inside the motor by utilizing anisotropic magnetic barriers of special shapes, thereby improving the efficiency and performance of the motor and reducing energy loss;

[0025] 2. The present invention can help improve the overall performance and reliability of the motor by dividing the rotor core or the anisotropic magnetic barrier hole into multiple parts to adapt to different magnetic field requirements and mechanical design requirements. At the same time, the symmetrical arrangement of the rotor core can ensure that the motor remains balanced during operation, reduce vibration and noise, and improve operational stability;

[0026] 3. The rotor body of the present invention is composed of a structure of multiple layers of rotor cores stacked together, which can not only optimize the magnetic properties of the rotor, but also provide better power output and higher efficiency;

[0027] 4. The present invention improves the q-axis inductance of the motor rotor by adjusting the ratio range between the sum of the widths of multiple magnetic conductive channels and the distance between the two ends of a group of anisotropic magnetic barrier holes, which can increase the inductance difference between the d-axis and q-axis of the motor, and is more conducive to improving the reluctance torque of the motor, so that the unit current generates a larger electromagnetic torque, thereby improving the efficiency of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The structure diagram of the rotor with segmented symmetrical stacking of special-shaped magnetic barrier punching sheets in the embodiment is shown;

[0029] Figure 2 What is shown is a schematic diagram of the structure of the rotor core in the embodiment;

[0030] Figure 3 What is shown is a schematic diagram of the structure of the core punching sheet in the embodiment;

[0031] Figure 4 Shown is a schematic structural diagram of a slot and an elastic plug-in block in an embodiment.

[0032] Description of reference numerals:

[0033] 10. Rotor body; 11. Rotating shaft; 12. Rotor fan; 13. Rotor core; 131. Core punching sheet; 132. Slot; 133. Elastic insert; 21. Through slot; 22. Through slot side wall one; 23. Through slot side wall two; 30. Permanent magnet; 40. Anisotropic magnetic barrier group; 41. Anisotropic magnetic barrier hole; 42. Magnetic barrier hole side wall one; 43. Magnetic barrier hole side wall two; 50. Magnetic channel one; 60. Magnetic channel two. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0035] When designing permanent magnets in magnetic barriers, it is necessary to consider the effect of permanent magnet flux on the degree of magnetic circuit saturation. A large permanent magnet flux is likely to cause magnetic circuit saturation and reduce the rotor salient pole ratio; while a small permanent magnet flux has little effect on the improvement of torque and power factor. Although low-performance permanent magnets have low coercive force, their demagnetization curve has good linearity.

[0036] The synthesis formula of reluctance torque and permanent magnet torque is as follows:

[0037] T=mp*(Lq-Ld)*id*iq+mp*ψPM*iq. in,

[0038] T is the output torque of the motor. Increasing the value of T can improve the performance of the motor. The first term in the equation after T is the reluctance torque, and the second term is the permanent magnet torque. ΨPM is the maximum value of the stator-rotor coupling flux generated by the permanent magnet of the motor, m is the number of phases of the stator conductor, Ld and Lq are the d-axis and q-axis inductances, respectively, where the d-axis refers to the axis coinciding with the main magnetic pole axis, and the q-axis refers to the axis perpendicular to the main magnetic pole axis, where perpendicular refers to the electrical angle; id and iq are the components of the armature current in the d-axis and q-axis directions, respectively. According to the formula, increasing the difference between the inductances of Ld and Lq and ψpm can increase the output torque, that is, while ensuring that one of the reluctance torque and the permanent magnet torque remains unchanged, increasing the other of the two can increase the total output torque of the motor, thereby improving the efficiency of the motor.

[0039] Example

[0040] like Figure 1 , Figure 2 and Figure 3 As shown, the rotor is symmetrically stacked in sections with heterogeneous magnetic barrier punchings, including multiple rotor bodies 10 and multiple heterogeneous magnetic barrier groups 40. One rotor body 10 includes a multi-layer rotor core 13. The rotor core 13 is assembled by splicing multiple core punchings 131. N groups of through slots 21 of the same shape and size are evenly arranged on the core punchings 131. The through slots 21 are provided with permanent magnets 30. The multiple heterogeneous magnetic barrier groups 40 are arranged on the side of the multiple through slots 21 away from the center of the core punchings 131. The heterogeneous magnetic barrier groups 40 include a group of heterogeneous magnetic barrier holes 41 arranged at intervals along the axial direction of the core punchings 131d. The number of a group of heterogeneous magnetic barrier holes 41 is set to M, and M is M. The anisotropic magnetic barrier holes 41 are arranged at intervals along the extension direction of the slot wall of the through slot 21. A magnetic conductive channel 50 is formed between any two adjacent anisotropic magnetic barrier holes 41 in a group of anisotropic magnetic barrier holes 41. The width of the magnetic conductive channel 50 is a1. The magnetic conductive channel 50 has a small magnetic resistance in the d-axis direction, a high magnetic flux, and a large inductance Ld. The magnetic conductive channel 50 has a very high magnetic resistance in the q-axis direction at the center line of the anisotropic magnetic barrier holes 41, and a small inductance Lq. The inductance difference between the d-axis and q-axis directions can be increased, thereby improving the torque output capacity of the motor. The distance between the two ends of a group of anisotropic magnetic barrier holes 41 is A, which satisfies 1 / 6≦M-1a1 / A≦4 / 3.

[0041] A plurality of through slots 21 are provided on the rotor core 13. The through slots 21 are arranged in a "U" shape. The through slots 21 may have one curved portion or may have multiple curved portions, and there is no specific limitation on this. When the through slots 21 have multiple curved portions, their shape is arranged in a wave shape. The through slots 21 are arranged at intervals along the circumference of the rotor core 13, and are specifically evenly distributed in the circumferential direction with the center of the rotor core 13 as the center of the circle. The two ends of the through slots 21 extend toward the edge of the core punching sheet 131. An area for setting a plurality of opposite magnetic barrier groups 40 is formed between the edges of the core punching sheet 131. The plurality of opposite magnetic barrier groups 40 are arranged on one side of the plurality of through slots 21 away from the center of the core punching sheet 131.

[0042] It should be noted that the through slots 21 are mainly used to install the permanent magnets 30, and the permanent magnets 30 have magnetic poles, so the number of the through slots 21 is set to an even number, such as Figure 2 As shown, eight through slots 21 are arranged at intervals along the circumferential direction of the rotor core 13, at least one permanent magnet 30 is placed in each through slot 21, the polarities of the permanent magnets 30 in any two adjacent through slots 21 are opposite, and the multiple permanent magnets 30 are alternately distributed along the circumferential direction of the rotor core 13 according to N poles and S poles.

[0043] Specifically, the rotor core 13 is driven by the magnetic effect of the permanent magnet 30, and the motor rotor can rotate relative to the motor stator to achieve normal operation of the motor. The rotor core 13 is made of stacked silicon steel punchings, has high magnetic flux rate, high structural strength, and is easy to process.

[0044] like Figure 2 and Figure 3 As shown, N groups of through slots 21 of the same shape and size are evenly arranged on the core punching sheet 131, and permanent magnets 30 are arranged in the through slots 21. The shortest distances between one through slot 21 and two adjacent through slots 21 are C1 and C2 respectively. The height of the permanent magnet 30 is B1, and the shortest distance between two adjacent through slots 21 is C2=kB1BrC1 / Bs, wherein k is an empirical coefficient, k≦0.5, Br is the remanence of the permanent magnet, Bs is the saturation magnetic flux density of the silicon steel sheet, a magnetic bridge is arranged between the end of the through slot 21 and the edge of the core punching sheet 131, and the distance Brib between the end of the through slot 21 and the edge of the core punching sheet 131 satisfies 0.5≦Brib.

[0045] Specifically, when N is 4, C1=5.3mm, B1=20.5mm, C2=kB1BrC1 / Bs=0.29×20.5×0.42×5.3÷2.2=6.015mm, where k is an empirical coefficient of 0.29, satisfying k≦0.5.

[0046] like Figure 2 and Figure 3 As shown, the through slot 21 has a through slot side wall 1 22 and a through slot side wall 23 that are relatively arranged, and the through slot side wall 1 22 and the through slot side wall 23 are both convexly arranged toward the center of the rotor core 13, and the thickness of the permanent magnet 30 in the axial direction of the core punching sheet 131d is B2, and the anisotropic magnetic barrier hole 41 has a magnetic barrier hole side wall 1 42 and a magnetic barrier hole side wall 2 43 that are relatively arranged, and the distance from the magnetic barrier hole side wall 1 42 to the magnetic barrier hole side wall 2 43 is the thickness a2 of the anisotropic magnetic barrier hole 41, and B2>a2.

[0047] It should be noted that the anisotropic magnetic barrier hole 41 is arranged between the side wall 22 of the through slot 21 and the edge of the rotor core 13. It can reduce the impact on the permanent magnetic force while regulating the path of the magnetic lines of force, weaken the magnetic field harmonics in the air gap, and alleviate the degree of magnetic saturation. A magnetic barrier is formed during the rotation of the motor rotor to increase the power density and torque density of the motor, enhance the overload capacity of the motor, and effectively improve the torque pulsation of the motor. On the basis of reducing the amount of permanent magnets 30 used in the motor, that is, reducing production costs, the motor performance is greatly improved and the product competitiveness is improved.

[0048] Specifically, by adjusting the ratio range between the sum of the widths of the plurality of magnetic conductive channels 50 and the distance between the two ends of a group of anisotropic magnetic barrier holes 41, the q-axis inductance of the motor rotor is increased, and the inductance difference between the d-axis and q-axis of the motor can be increased, which is more conducive to improving the magnetic resistance torque of the motor, so that a larger electromagnetic torque is generated per unit current, thereby improving the efficiency of the motor. The amount of permanent magnets 30 placed in the through slots 21 of the single-layer structure is reduced compared to the amount of permanent magnets 30 placed in the double-layer structure, thereby reducing the production cost of the symmetrical stacked rotor.

[0049] like Figure 2 and Figure 3 As shown, the thickness of the middle part of the permanent magnet 30 is greater than the thickness at both ends. The permanent magnet 30 adopts a structure that is thick in the middle and thin at both ends, which will increase the width of the magnetic channel 2 60, thereby increasing the q-axis inductance, that is, increasing the value of Lq, so that the inductance difference between Ld and Lq increases, increasing the magnetic resistance torque, and thus improving the torque output capacity of the motor.

[0050] It should be noted that the greater the thickness of the permanent magnet 30 in the d-axis direction of the motor rotor with the magnetic barrier, the higher the permanent magnet torque of the motor, thereby increasing the output torque of the motor and improving the efficiency of the motor. In order to ensure that the magnetic path in the magnetic conductive channel 2 60 is not blocked, the thickness of the anisotropic magnetic barrier hole 41 should not be too large. Therefore, the thickness of the permanent magnet 30 is set to be greater than the thickness of a layer of anisotropic magnetic barrier hole 41. The thickness of the anisotropic magnetic barrier hole 41 refers to the distance from the magnetic barrier hole side wall 1 42 to the magnetic barrier hole side wall 2 43 of the anisotropic magnetic barrier hole 41. If the magnetic barrier hole side wall 1 42 and the magnetic barrier are If the hole side walls 43 are arranged in parallel, the thickness of the anisotropic magnetic barrier hole 41 refers to the shortest distance from the magnetic barrier hole side walls 42 to the magnetic barrier hole side walls 43. If the magnetic barrier hole side walls 42 and the magnetic barrier hole side walls 43 are not arranged in parallel, the thickness of the anisotropic magnetic barrier hole 41 refers to the distance from the magnetic barrier hole side walls 42 near the middle part of the anisotropic magnetic barrier hole 41 to the magnetic barrier hole side walls 43. If the anisotropic magnetic barrier hole 41 is designed in an irregular shape, the thickness of the anisotropic magnetic barrier hole 41 can be the average value between the maximum distance and the minimum distance from the magnetic barrier hole side walls 42 to the magnetic barrier hole side walls 43.

[0051] like Figure 3 As shown, gaps are provided at both ends of the permanent magnet 30 and the through slot 21, which effectively avoids the situation where the d-axis armature magnetic potential is concentrated on the ends of the permanent magnet 30, and can greatly improve the demagnetization current of the motor. The gaps are used to fill non-magnetic conductive media. By filling the non-magnetic conductive media, the ends of the permanent magnet 30 are prevented from being easily demagnetized and magnetized unsaturated, and the anti-demagnetization ability of the motor is also improved.

[0052] like Figure 1 and Figure 4 As shown, the core punching sheets 131 are assembled by a splicing mechanism, which includes an elastic plug 133 fixed on the side wall of the core punching sheet 131, and a slot 132 adapted to the core punching sheet 131 is provided on the side away from the elastic plug 133. A core punching sheet 131 inserts its elastic plug 133 into the slot 132 of the adjacent core punching sheet 131 to eventually obtain a circular rotor core 13, which is then stacked and sleeved on the rotating shaft 11, and finally fixed to the rotating shaft 11 through two rotor fans 12.

[0053] The present invention also includes a method for preparing a rotor with a segmented symmetrical stack of special-shaped magnetic barrier punching sheets, the method comprising the following steps:

[0054] S1, punching segmentation: cold-rolled silicon steel is processed into a core punching 131 of a predetermined shape by a stamping die, and the punching is segmented, and a layer of insulating paint is applied on the surface;

[0055] S2, magnetic barrier design: a through slot 21 and an anisotropic magnetic barrier group 40 are provided on the stamped core punching sheet 131, and a permanent magnet 30 is embedded in the through slot 21;

[0056] S3, punching sheet assembly: assemble multiple iron core punching sheets 131 into a complete rotor iron core 13, then stack and sleeve the multiple complete rotor iron cores 13 on the rotating shaft 11, and finally fix the multiple complete punching sheets on the rotating shaft 11 by two rotor fans 12.

[0057] The present invention also includes a motor, including a rotor and a motor stator, which are symmetrically stacked in sections with the above-mentioned special-shaped magnetic barrier punching sheets, and the motor stator is sleeved on the circumference of the rotor.

[0058] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them.

Claims

1. The rotor is made of symmetrically stacked sections with special-shaped magnetic barrier punchings, characterized in that: include: A plurality of rotor bodies (10), one of the rotor bodies (10) comprising a multi-layer rotor core (13), the rotor core (13) being assembled by splicing a plurality of core punching sheets (131), the core punching sheets (131) being evenly provided with N groups of through slots (21) of the same shape and size, and the through slots (21) being provided with permanent magnets (30); A plurality of heterogeneous magnetic barrier groups (40) are provided, wherein the plurality of heterogeneous magnetic barrier groups (40) are arranged on one side of the plurality of through slots (21) away from the center of the iron core punching sheet (131), wherein the heterogeneous magnetic barrier group (40) comprises a group of heterogeneous magnetic barrier holes (41) arranged at intervals along the d-axis direction of the iron core punching sheet (131), wherein the number of the heterogeneous magnetic barrier holes (41) in a group is set to M, wherein the M heterogeneous magnetic barrier holes (41) are arranged at intervals along the extension direction of the slot wall of the through slot (21), and a magnetic conductive channel (50) is formed between any two adjacent heterogeneous magnetic barrier holes (41) in a group of the heterogeneous magnetic barrier holes (41).

2. The segmented symmetrical stacked rotor with special-shaped magnetic barrier punchings according to claim 1 is characterized in that: The width of the magnetic conductive channel 1 (50) is a1, and the distance between the two ends of a group of the heterogeneous magnetic barrier holes (41) is A, which satisfies 1 / 6≦(M-1)a1 / A≦4 / 3.

3. The segmented symmetrical stacked rotor with special-shaped magnetic barrier punchings according to claim 1 is characterized in that: The shortest distances between one through slot (21) and two adjacent through slots (21) are C1 and C2 respectively, the height of the permanent magnet (30) is B1, and the shortest distance between two adjacent through slots (21) is C2=kB1BrC1 / Bs, wherein k is an empirical coefficient, k≦0.5, Br is the remanence of the permanent magnet, and Bs is the saturation magnetic flux density of the silicon steel sheet.

4. The segmented symmetrical stacked rotor with special-shaped magnetic barrier punchings according to claim 3 is characterized in that: A magnetic bridge is provided between the end of the through slot (21) and the edge of the iron core punching sheet (131), and the distance Brib between the end of the through slot (21) and the edge of the iron core punching sheet (131) satisfies 0.5≦Brib.

5. The segmented symmetrical stacked rotor with special-shaped magnetic barrier punchings according to claim 2 is characterized in that: The thickness of the permanent magnet (30) in the d-axis direction of the core punching sheet (131) is B2, the anisotropic magnetic barrier hole (41) has a magnetic barrier hole side wall 1 (42) and a magnetic barrier hole side wall 2 (43) arranged opposite to each other, the distance from the magnetic barrier hole side wall 1 (42) to the magnetic barrier hole side wall 2 (43) is the thickness a2 of the anisotropic magnetic barrier hole (41), and B2>a2.

6. The segmented symmetrical stacked rotor with special-shaped magnetic barrier punchings according to claim 5 is characterized in that: The thickness of the middle portion of the permanent magnet (30) is greater than the thickness of the two ends.

7. The segmented symmetrical stacked rotor with special-shaped magnetic barrier punchings according to claim 2 is characterized in that: Gaps are provided at both ends of the permanent magnet (30) and at both ends of the through slot (21), and the gaps are used to be filled with non-magnetic conductive media.

8. A method for preparing a rotor with segmented symmetrical stacking of special-shaped magnetic barrier punching sheets, the method comprising the following steps: S1, punching sheet segmentation: cold-rolled silicon steel is processed into a core punching sheet (131) of a predetermined shape by a stamping die, and the punching sheet is segmented, and a layer of insulating paint is applied on the surface; S2, magnetic barrier design: a through slot (21) and an anisotropic magnetic barrier group (40) are provided on the stamped iron core punching sheet (131), and a permanent magnet (30) is embedded in the through slot (21); S3, punching sheet assembly: assembling a plurality of iron core punching sheets (131) into a complete rotor iron core (13), then stacking and sleeve-mounting the plurality of complete rotor iron cores (13) on the rotating shaft (11), and finally fixing the plurality of complete punching sheets on the rotating shaft (11) by two rotor fans (12).

9. Motor, including: The segmented symmetrical stacked rotor with special-shaped magnetic barrier punchings as described in any one of claims 1 to 7; and The motor stator is sleeved on the circumference of the rotor.

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