Rotor punching sheet and permanent magnet synchronous driving motor formed by same

Abstract

The utility model provides a rotor punching sheet and a permanent magnet synchronous driving motor formed by the same. A central shaft hole is arranged at the center of the rotor punching sheet. The rotor punching sheet comprises M punching sheet units, and the M punching sheet units are symmetrically arranged relative to a central shaft hole of the rotor punching sheet; m is an even number greater than 0; a through hole is formed in the punching sheet unit, and the through hole is located in a high flux density area of the punching sheet unit; and the high flux density area is located at one side, far away from the central shaft hole, of the punching sheet unit. The through holes are formed in the high flux density area, the area of the flux density saturation area is reduced, meanwhile, the harmonic content is reduced, and then iron loss is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of rotor punching structure design, in particular to a rotor punching and a permanent magnet synchronous drive motor formed thereof. Background Art

[0002] In the structural design of high-speed permanent magnet motors, in order to improve the power density of the entire machine, it is usually necessary to design a higher electromagnetic load, which leads to greater losses per unit volume. The losses determine the overall efficiency of the motor. Most of the losses must be converted into heat energy. Given the limited size of the high-speed motor rotor and the usually fully enclosed structure, especially in an environment with difficult heat dissipation, it is easy to cause stator and rotor overheating, which in turn threatens the safe and stable operation of the motor.

[0003] In existing technology, an increasing number of motors are powered by inverters to achieve various complex motor control functions. When powered by an inverter, the output voltage contains not only the fundamental voltage component required for motor drive but also a large number of harmonics, which severely distorts the magnetic field waveform within the motor core. During motor development, it is necessary to pre-calculate iron loss and its specific distribution to identify areas with the greatest energy-saving potential. Further improvements to the motor core structure can reduce iron loss, thereby improving motor efficiency and reducing temperature rise.

[0004] The existing technologies all reduce iron loss by designing the structure and position of the inner and outer magnetic steel slots. However, due to the limitations of the shape and structural design of the inner and outer magnetic steel slots, the iron loss can only be reduced within a certain range and cannot meet the further optimization needs of high-speed permanent magnet synchronous drive motors. Utility Model Content

[0005] In order to overcome the problems existing in the related art, one of the purposes of the present invention is to provide a rotor punching, which sets through holes in the high magnetic density area to reduce the area of ​​the magnetic density saturation area, while reducing the harmonic content and thereby reducing iron loss.

[0006] A rotor punching, wherein a central axis hole is provided at the center of the rotor punching; the rotor punching comprises M punching units, and the M punching units are symmetrically arranged relative to the central axis hole of the rotor punching; M is an even number greater than 0;

[0007] A through hole is provided in the punching unit, and the through hole is located in a high magnetic density area of ​​the punching unit; the high magnetic density area is located on a side of the punching unit away from the central axis hole.

[0008] This application reduces the area of ​​the magnetic density saturation region by setting through holes in the high magnetic density region, while reducing the harmonic content, thereby reducing iron loss and improving motor efficiency.

[0009] In a preferred technical solution of the present invention, the distance between the side of the high magnetic density area away from the central axis hole and the central axis hole is R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole is R2, R2 = (R0-7.2mm) ~ (R0-3mm); R1 = (R2+2.5mm) ~ R, R0 is the radius of the rotor punching.

[0010] This application further accurately defines the range of the high magnetic density area based on the radius size of the rotor punching, ensuring the accurate position of the through hole setting, so as to reduce the area of ​​the magnetic density saturation region, while reducing the harmonic content, thereby reducing iron loss and improving motor efficiency.

[0011] In a preferred technical solution of the present invention, the punching unit is provided with an inner magnetic steel slot, and the inner magnetic steel is inserted into the inner magnetic steel slot; the distance between the side of the inner magnetic steel slot away from the central axis hole and the central axis hole is R, R = (R0-1.2mm) ~ (R0-0.5mm);

[0012] The distance between the side of the high magnetic density area away from the central axis hole and the central axis hole is R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole is R2, R2 = (R-6mm) ~ (R-2.5mm); R1 = (R2+2.5mm) ~ R.

[0013] Since the inner magnetic steel in the inner magnetic steel slot plays the role of generating magnetic field and current, further determining the scope of the high magnetic density area based on the position of the inner magnetic steel will improve the definition accuracy of the high magnetic density area, thereby ensuring the accurate position of the through-hole setting, so as to reduce the area of ​​the magnetic density saturation region, while reducing the harmonic content, thereby reducing iron loss and improving motor efficiency.

[0014] In a preferred technical solution of the present invention, an outer magnetic steel slot is provided on the side of the inner magnetic steel slot close to the central unit axis, and the central unit axis is located at the center of the punching unit and in the same direction as the radius of the punching unit;

[0015] The through hole is located between the inner magnetic steel slot and the outer magnetic steel slot.

[0016] The outer magnetic steel slots are used to plug in the outer magnetic steel. The outer magnetic steel and the inner magnetic steel work together to generate a magnetic field that can interact with the wires in the stator, thereby forming an induced electromotive force and generating current. The position design of the outer magnetic steel slots and the inner magnetic steel slots in this application ensures that the structural design of the punching unit is reasonable and maximizes its effectiveness. In the punching unit, the outer magnetic steel slots and the outer magnetic steel slots are used to plug in the inner magnetic steel and the outer magnetic steel, and the high magnetic density area between the two is the largest magnetic density area; providing a through hole in the high magnetic density area between the two can effectively reduce the area of ​​the high magnetic density area, thereby reducing the rotor iron loss and improving the efficiency of the motor.

[0017] In a preferred technical solution of the present invention, the cross-section of the through hole is triangular; the side of the through hole close to the inner magnetic steel slot is the first side D1 of the through hole, the side of the through hole close to the outer magnetic steel slot is the second side D2 of the through hole, and the area between the first side and the second side of the through hole is the third side D3 of the through hole; the side of the inner magnetic steel slot close to the through hole is the first side B1 of the inner magnetic steel slot;

[0018] The angle between the first side D1 of the through hole and the first side B1 of the inner magnetic steel slot is β, β = 21° to 23°;

[0019] The minimum distance between the first side D1 of the through hole and the first side B1 of the inner magnetic steel slot is d, where d=0.7-1.2 mm.

[0020] The above-mentioned limitations on the angle and the minimum distance d can ensure that the through hole is close to the inner magnetic steel slot, without affecting the fundamental wave, that is, without affecting the output torque, while reducing the harmonic content, thereby reducing the rotor iron loss and improving the motor efficiency.

[0021] In a preferred technical solution of the present invention, the cross-section of the through hole is triangular; the side of the through hole close to the inner magnetic steel slot is the first side D1 of the through hole, the side of the through hole close to the outer magnetic steel slot is the second side D2 of the through hole, and the area between the first side and the second side of the through hole is the third side D3 of the through hole; the side of the inner magnetic steel slot close to the through hole is the first side B1 of the inner magnetic steel slot;

[0022] The included angle between the second side D2 of the through hole and the axis of the central unit is γ, γ = 65° to 70°;

[0023] The minimum distance between the second side D2 of the through hole and the first side B1 of the inner magnetic steel slot is c, where c=1.5-3.5 mm.

[0024] The above-mentioned constraint relationship between proportions and dimensions enables the through hole to reduce torque pulsation without affecting the output torque, thereby reducing motor noise and vibration.

[0025] In a preferred technical solution of the present invention, the corner connection of the through hole is chamfered, and the radius of the chamfered corner is RD, RD = 0.2 ~ 0.5 mm.

[0026] The rounded corner design facilitates the processing and forming of through holes, improving the preparation efficiency of rotor punchings.

[0027] In a preferred technical solution of the present invention, there are two inner magnetic steel slots, which are symmetrically distributed relative to the central unit axis, and are V-shaped with their openings facing the outside of the punching unit.

[0028] There are two outer magnetic steel slots, which are symmetrically distributed relative to the central unit axis, and are V-shaped with their openings facing the outside of the punching unit;

[0029] There are two through holes, and the two through holes are symmetrically distributed relative to the central unit axis.

[0030] In the present application, there are two inner magnetic steel slots, which are symmetrically distributed relative to the axis of the central unit, and the two inner magnetic steel slots are V-shaped, and the two inner magnetic steel slots with V-shaped distribution have openings facing away from the central axis hole. The structural design of the inner magnetic steel slots in the present application can ensure that the inner magnetic steel can fully play its role, thereby improving the space utilization rate of the rotor punching. In the present application, there are two outer magnetic steel slots, which are symmetrically distributed relative to the axis of the central unit, and the two outer magnetic steel slots are V-shaped, and the two outer magnetic steel slots with V-shaped distribution have openings facing away from the central axis hole. The structural design of the inner and outer magnetic steel slots in the present application can ensure that the inner magnetic steel can fully play its role, thereby improving the space utilization rate of the rotor punching. In the punching unit, the outer magnetic steel slots and the outer magnetic steel slots are used to plug in the inner magnetic steel and the outer magnetic steel, and the high magnetic density area between the two is the largest magnetic density area; setting a through hole in the high magnetic density area between the two can effectively reduce the area of ​​the high magnetic density area, thereby reducing the rotor iron loss and improving the motor efficiency.

[0031] In a preferred technical solution of the present invention, the radius of the rotor punching is 240-260 mm.

[0032] A permanent magnet synchronous drive motor comprises the rotor punching sheet described above.

[0033] The present application provides a permanent magnet synchronous drive motor, comprising a rotor punching as described above.

[0034] The permanent magnet synchronous drive motor formed in this application reduces the harmonic content by 50%, the torque pulsation by 27%, the iron loss in the full speed range by 10%, and the maximum efficiency of the motor by 0.4% while ensuring that the output torque remains basically unchanged.

[0035] The beneficial effects of the utility model are:

[0036] The utility model provides a rotor lamination, wherein a central axis hole is provided at the center of the rotor lamination; the rotor lamination includes M lamination units, which are symmetrically arranged relative to the central axis hole of the rotor lamination; M is an even number greater than 0; the lamination units are provided with through holes, and the through holes are located in a high magnetic flux density region of the lamination units; the high magnetic flux density region is located on a side of the lamination unit away from the central axis hole. By providing through holes in the high magnetic flux density region, the present application reduces the area of ​​the magnetic flux density saturation region and simultaneously reduces the harmonic content, thereby reducing iron loss and improving motor efficiency.

[0037] The utility model also provides a permanent magnet synchronous drive motor including the above-mentioned rotor punchings, which reduces the area of ​​the magnetic density saturation region by arranging through holes in the high magnetic density region, reduces the harmonic content, and thus reduces iron loss and improves the motor efficiency. The final permanent magnet synchronous drive motor reduces the harmonic content by 50%, the torque pulsation by 27%, the iron loss by 10% in the full speed range, and the maximum efficiency of the motor is improved by 0.4% while ensuring that the output torque remains basically unchanged. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the structure of the rotor punching of this application;

[0039] Figure 2 Schematic diagram of the positions of the inner magnetic steel slots, outer magnetic steel slots and through holes in the punching unit of this application;

[0040] Figure 3 Schematic diagram of the distance between the inner magnetic steel slot, outer magnetic steel slot, through hole and central axis hole in the punching unit of this application;

[0041] Figure 4 Schematic diagram of the angle between the inner magnetic steel slot and the through hole;

[0042] Figure 5 Schematic diagram of the distance between the inner magnetic steel slot and the outer magnetic steel slot;

[0043] Figure 6 Schematic diagram of the dimensions of the inner and outer magnetic steel layers;

[0044] Figure 7 Schematic diagram of the rotor lamination iron loss optimization results in the comparative example and the experimental example;

[0045] Figure 8 Optimization results of rotor punching torque ripple in comparative example and experimental example;

[0046] Figure 9 These are the optimization results of the harmonic content of the rotor laminations in the comparative example and the experimental example.

[0047] Reference numerals:

[0048] 11. Punching unit; 12. Inner magnetic steel slot; 13. Outer magnetic steel slot; 14. Through hole; 15. Center axis hole; 16. Center unit axis. DETAILED DESCRIPTION

[0049] The following describes preferred embodiments of the present invention in more detail with reference to the accompanying drawings. Although preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0050] The terms used in this utility model are for the purpose of describing specific embodiments only and are not intended to limit the utility model. As used in this utility model and the appended claims, the singular forms "a," "the," and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0051] It should be understood that although the terms "first", "second", "third", etc. may be used in the present invention to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of the present invention, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0052] Example 1

[0053] like Figures 1-6 As shown, a rotor punching sheet is provided with a central axis hole 15 at the center of the rotor punching sheet; the rotor punching sheet comprises M punching sheet units 11, and the M punching sheet units 11 are symmetrically arranged relative to the central axis hole 15 of the rotor punching sheet; M is an even number greater than 0. Figure 1 As shown, M=8, that is, eight punching units 11 are symmetrically arranged along the central axis hole 15 and spliced ​​into a rotor punching. The structure of each punching unit 11 in this application is the same, so the structure of one punching unit 11 is used as an example for detailed description below.

[0054] The high magnetic density area is located on the side of the punching unit 11 away from the central axis hole, that is, away from the central axis hole 15. The central axis hole 15 refers to the center position of the cylindrical rotor punching. In actual operation, a gap is set at the center of the circle, that is, a fan-shaped gap is set at the position of each punching unit 11 close to the central axis hole 15, and a circular gap is formed at the center position of the finally formed rotor punching, such as Figure 1As shown, a circular notch is formed in the center of the rotor punching, and the central shaft hole 15 refers to the center position of the circular notch.

[0055] In the present application, each punching unit 11 is provided with a through hole 14, which is located in a high magnetic flux density region of the punching unit 11; the high magnetic flux density region is located on the side of the punching unit 11 away from the central axis hole 15. By providing the through hole 14 in the high magnetic flux density region, the area of ​​the magnetic flux density saturation region is reduced, and the harmonic content is reduced, thereby reducing iron loss and improving motor efficiency.

[0056] In the present application, the number of through holes 14 can be one or more, the purpose of which is to reduce the area of ​​the magnetic density saturation region, while reducing the harmonic content, thereby reducing iron loss.

[0057] In the present application, the punching unit 11 may further include a magnetic steel slot, in which a magnetic steel is inserted. The magnetic field of the magnetic steel may interact with the conducting wire in the stator, thereby forming an induced electromotive force and generating current.

[0058] Example 2

[0059] like Figures 1-6 As shown, this embodiment provides a rotor punching, wherein a central axis hole 15 is provided at the center of the rotor punching; the rotor punching includes M punching units 11, and the M punching units 11 are symmetrically arranged relative to the central axis hole 15 of the rotor punching; M is an even number greater than 0; a through hole 14 is provided in the punching unit 11, and the through hole 14 is located in a high magnetic flux density region of the punching unit 11; the high magnetic flux density region is located on the side of the punching unit 11 away from the central axis hole 15. By providing the through hole 14 in the high magnetic flux density region, the present application reduces the area of ​​the magnetic flux saturation region and reduces the harmonic content, thereby reducing iron loss and improving motor efficiency.

[0060] Attachment Figure 2-Figure 4 The position of O in the middle is the position of the central axis hole 15.

[0061] This embodiment defines the distance between the side of the high magnetic density area away from the central axis hole and the central axis hole 15 as R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole 15 as R2, R2 = (R0-7.2mm) ~ (R0-3mm); R1 = (R2+2.5mm) ~ R, R0 is the radius of the rotor punching.

[0062] like Figure 2 and Figure 3As shown, the high magnetic flux density region is an annular area located outside the rotor lamination. The distance between the side of the annular region away from the central axis hole, that is, the side away from the central axis hole 15, and the central axis hole 15 is R1. The distance between the side of the high magnetic flux density region close to the central axis hole, that is, the side close to the central axis hole 15, and the central axis hole 15 is R2. R2 = (R0 - 7.2mm) to (R0 - 3mm); R1 = (R2 + 2.5mm) to R, where R0 is the radius of the rotor lamination. The value of R0 can range from 240 to 260mm.

[0063] This application further accurately defines the range of the high magnetic density area based on the radius size of the rotor punching, ensuring the accurate position of the through hole 14 to reduce the area of ​​the magnetic density saturation area, while reducing the harmonic content, thereby reducing iron loss and improving motor efficiency.

[0064] Furthermore, in the present application, the punching unit 11 is provided with an inner magnetic steel slot 12, and the inner magnetic steel slot 12 is inserted into the inner magnetic steel; the distance from the side of the inner magnetic steel slot 12 away from the central axis hole to the central axis hole 15 is R, R = (R0-1.2mm) ~ (R0-0.5mm). Figure 3 As shown, the middle position of the inner magnetic steel slot 12 is a rectangular structure, and the two ends are arc-shaped structures, where the two ends refer to the two sides close to the central axis hole 15 or away from the central axis hole 15.

[0065] This application defines the dimensional relationship between the side of the inner magnetic steel slot 12 away from the central axis hole and the punching unit 11. That is, the side of the inner magnetic steel slot 12 away from the central axis hole is located inside the rotor punching and maintains a distance of 0.5-1.2 mm from the side of the rotor punching away from the central axis hole. This distance ensures that the inner magnetic steel in the inner magnetic steel slot 12 can fully function.

[0066] When the position of the inner magnetic steel slot 12 is determined, the distance between the side of the high magnetic density area away from the central axis hole and the central axis hole 15 in this application is R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole 15 is R2, R2 = (R-6mm) ~ (R-2.5mm); R1 = (R2+2.5mm) ~ R.

[0067] That is to say, on the basis of defining the position of the inner magnetic steel slot 12, the present application further defines the position of the high magnetic density area according to the position of the inner magnetic steel slot 12, ensuring that the side of the high magnetic density area close to the central axis hole is kept at a distance of 2.5-6 mm from the side of the inner magnetic steel slot 12 away from the central axis hole, thereby defining a more precise range and position of the high magnetic density area.

[0068] Since the inner magnetic steel in the inner magnetic steel slot 12 plays the role of generating magnetic field and current, further determining the range of the high magnetic density area according to the position of the inner magnetic steel will improve the definition accuracy of the high magnetic density area, thereby ensuring the accurate position of the through hole 14, so as to reduce the area of ​​the magnetic density saturation area, and at the same time reduce the harmonic content, thereby reducing iron loss and improving motor efficiency.

[0069] In this embodiment, the shape of the through hole 14 can be any shape, as long as the through hole 14 is located within the high magnetic field density area. Specifically, the cross-section of the through hole 14 can be triangular, circular, rectangular, diamond-shaped, etc., and it is necessary to ensure that the through hole 14 is completely located within the high magnetic field density area.

[0070] In the present application, an outer magnetic steel slot 13 is provided on the side of the inner magnetic steel slot 12 close to the central unit axis 16, and the central unit axis 16 is located at the center position of the punching unit 11 and in the same direction as the radius of the punching unit 11; the through hole 14 is located between the inner magnetic steel slot 12 and the outer magnetic steel slot 13.

[0071] The outer magnetic steel slot 13 is used to plug in the outer magnetic steel. The outer magnetic steel and the inner magnetic steel work together, and the magnetic field generated by them can interact with the wires in the stator, thereby forming an induced electromotive force and generating current. The position design of the outer magnetic steel slot 13 and the inner magnetic steel slot 12 in this application ensures that the structural design of the punching unit 11 is reasonable and maximizes its effectiveness. In the punching unit 11, the outer magnetic steel slot 13 and the outer magnetic steel slot 13 are used to plug in the inner magnetic steel and the outer magnetic steel, and the high magnetic density area between the two is the largest magnetic density area; a through hole 14 is provided in the high magnetic density area between the two, which can effectively reduce the area of ​​the high magnetic density area, thereby reducing the rotor iron loss and improving the efficiency of the motor.

[0072] In the present application, there are two inner magnetic steel slots 12 , which are symmetrically distributed relative to the central unit axis 16 , and are V-shaped with their openings facing the outside of the punching unit 11 .

[0073] In the present application, there are two inner magnetic steel slots 12, which are symmetrically distributed relative to the central unit axis 16. The two inner magnetic steel slots 12 are arranged in a V-shape, and the two inner magnetic steel slots 12 arranged in the V-shape have openings facing away from the central axis hole 15. The structural design of the inner magnetic steel slots 12 in the present application ensures that the inner magnetic steel can fully function, thereby improving the space utilization of the rotor punchings.

[0074] There are two outer magnetic steel slots 13 in the present application. The two outer magnetic steel slots 13 are symmetrically distributed relative to the central unit axis 16 , and the two outer magnetic steel slots 13 are V-shaped with their openings facing the outside of the punching unit 11 .

[0075] In the present application, there are two outer magnetic steel slots 13, which are symmetrically distributed relative to the central unit axis 16. The two outer magnetic steel slots 13 are arranged in a V-shape, and the two outer magnetic steel slots 13 arranged in the V-shape have openings facing away from the central axis hole 15. The structural design of the inner and outer magnetic steel slots 13 in the present application ensures that the inner magnetic steel can fully function, thereby improving the space utilization of the rotor punching.

[0076] In the present application, there are two through holes 14 , and the two through holes 14 are symmetrically distributed relative to the central unit axis 16 .

[0077] In the punching unit 11, the outer magnetic steel slot 13 and the outer magnetic steel slot 13 are used to plug the inner magnetic steel and the outer magnetic steel, and the high magnetic density area between the two is the largest magnetic density area; a through hole 14 is set in the high magnetic density area between the two, which can effectively reduce the area of ​​the high magnetic density area, thereby reducing the rotor iron loss and improving the motor efficiency.

[0078] Example 3

[0079] like Figures 1-6 As shown, this embodiment provides a rotor punching, wherein a central axis hole 15 is provided at the center of the rotor punching; the rotor punching includes M punching units 11, and the M punching units 11 are symmetrically arranged relative to the central axis hole 15 of the rotor punching; M is an even number greater than 0; a through hole 14 is provided in the punching unit 11, and the through hole 14 is located in a high magnetic flux density region of the punching unit 11; the high magnetic flux density region is located on the side of the punching unit 11 away from the central axis hole 15. By providing the through hole 14 in the high magnetic flux density region, the present application reduces the area of ​​the magnetic flux saturation region and reduces the harmonic content, thereby reducing iron loss and improving motor efficiency.

[0080] like Figures 1-6 As shown, this embodiment provides a rotor punching, wherein a central axis hole 15 is provided at the center of the rotor punching; the rotor punching includes M punching units 11, and the M punching units 11 are symmetrically arranged relative to the central axis hole 15 of the rotor punching; M is an even number greater than 0; a through hole 14 is provided in the punching unit 11, and the through hole 14 is located in a high magnetic density area of ​​the punching unit 11; the high magnetic density area is located on the side of the punching unit 11 away from the central axis hole 15.

[0081] like Figure 2 As shown, in the present application, the punching unit 11 is provided with an inner magnetic steel slot 12, and the inner magnetic steel slot 12 is inserted into the inner magnetic steel; the distance from the side of the inner magnetic steel slot 12 away from the central axis hole to the central axis hole 15 is R, R = (R0-1.2mm) ~ (R0-0.5mm). Figure 3As shown, the middle position of the inner magnetic steel slot 12 is a rectangular structure, and the two ends are arc-shaped structures, where the two ends refer to the two sides close to the central axis hole 15 or away from the central axis hole 15. The distance between the side of the high magnetic density area away from the central axis hole and the central axis hole 15 is R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole 15 is R2, R2 = (R-6mm) ~ (R-2.5mm); R1 = (R2+2.5mm) ~ R.

[0082] The above-mentioned size ratio relationship of the present application enables the through hole 14D to be located in the high magnetic density area at the outer end of the rotor. The existence of the through hole 14 reduces the area of ​​the high magnetic density area, thereby reducing the rotor iron loss and improving the motor efficiency.

[0083] In the present application, an outer magnetic steel slot 13 is provided on the side of the inner magnetic steel slot 12 close to the central unit axis 16, and the central unit axis 16 is located at the center position of the punching unit 11 and in the same direction as the radius of the punching unit 11; the through hole 14 is located between the inner magnetic steel slot 12 and the outer magnetic steel slot 13.

[0084] The central unit axis 16 is defined to be located at the center of the punching unit 11 and is in the same direction as the radius of the punching unit 11 .

[0085] In the present application, there are two inner magnetic steel slots 12 , which are symmetrically distributed relative to the central unit axis 16 , and are V-shaped with their openings facing the outside of the punching unit 11 .

[0086] There are two outer magnetic steel slots 13 in the present application. The two outer magnetic steel slots 13 are symmetrically distributed relative to the central unit axis 16 , and the two outer magnetic steel slots 13 are V-shaped with their openings facing the outside of the punching unit 11 .

[0087] In the present application, there are two through holes 14 , and the two through holes 14 are symmetrically distributed relative to the central unit axis 16 .

[0088] Furthermore, in the present application, the cross section of the through hole 14 is triangular; the side of the through hole 14 close to the inner magnetic steel slot 12 is defined as the first side D1 of the through hole 14, the side of the through hole 14 close to the outer magnetic steel slot 13 is defined as the second side D2 of the through hole 14, and the area between the first side of the through hole 14 and the second side of the through hole 14 is defined as the third side D3 of the through hole 14; the side of the inner magnetic steel slot 12 close to the through hole 14 is defined as the first side B1 of the inner magnetic steel slot 12. Figure 3 and Figure 4 As shown, the present application defines the angle between the first side D1 of the through hole 14 and the first side B1 of the inner magnetic steel slot 12 as β, β = 21°~23°; the present application defines the minimum distance between the first side D1 of the through hole 14 and the first side B1 of the inner magnetic steel slot 12 as d, d = 0.7~1.2mm.

[0089] The above-mentioned limitations on the angle and the minimum distance d can ensure that the through hole 14 is close to the inner magnetic steel slot 12 without affecting the fundamental wave, that is, without affecting the output torque, while reducing the harmonic content, thereby reducing the rotor iron loss and improving the motor efficiency.

[0090] Example 4

[0091] like Figures 1-6 As shown, this embodiment provides a rotor punching, wherein a central axis hole 15 is provided at the center of the rotor punching; the rotor punching includes M punching units 11, and the M punching units 11 are symmetrically arranged relative to the central axis hole 15 of the rotor punching; M is an even number greater than 0; a through hole 14 is provided in the punching unit 11, and the through hole 14 is located in a high magnetic density area of ​​the punching unit 11; the high magnetic density area is located on the side of the punching unit 11 away from the central axis hole 15.

[0092] like Figure 2 As shown, in the present application, the punching unit 11 is provided with an inner magnetic steel slot 12, and the inner magnetic steel slot 12 is inserted into the inner magnetic steel; the distance from the side of the inner magnetic steel slot 12 away from the central axis hole to the central axis hole 15 is R, R = (R0-1.2mm) ~ (R0-0.5mm). Figure 3 As shown, the middle position of the inner magnetic steel slot 12 is a rectangular structure, and the two ends are arc-shaped structures, where the two ends refer to the two sides close to the central axis hole 15 or away from the central axis hole 15. The distance between the side of the high magnetic density area away from the central axis hole and the central axis hole 15 is R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole 15 is R2, R2 = (R-6mm) ~ (R-2.5mm); R1 = (R2+2.5mm) ~ R.

[0093] The above-mentioned size ratio relationship of the present application enables the through hole 14D to be located in the high magnetic density area at the outer end of the rotor. The existence of the through hole 14 reduces the area of ​​the high magnetic density area, thereby reducing the rotor iron loss and improving the motor efficiency.

[0094] In the present application, an outer magnetic steel slot 13 is provided on the side of the inner magnetic steel slot 12 close to the central unit axis 16, and the central unit axis 16 is located at the center position of the punching unit 11 and in the same direction as the radius of the punching unit 11; the through hole 14 is located between the inner magnetic steel slot 12 and the outer magnetic steel slot 13.

[0095] The central unit axis 16 is defined to be located at the center of the punching unit 11 and is in the same direction as the radius of the punching unit 11 .

[0096] In the present application, there are two inner magnetic steel slots 12 , which are symmetrically distributed relative to the central unit axis 16 , and are V-shaped with their openings facing the outside of the punching unit 11 .

[0097] There are two outer magnetic steel slots 13 in the present application. The two outer magnetic steel slots 13 are symmetrically distributed relative to the central unit axis 16 , and the two outer magnetic steel slots 13 are V-shaped with their openings facing the outside of the punching unit 11 .

[0098] In the present application, there are two through holes 14 , and the two through holes 14 are symmetrically distributed relative to the central unit axis 16 .

[0099] Furthermore, the cross section of the through hole 14 of the present application is triangular; Figure 3 and Figure 4 As shown, the side of the through hole 14 close to the inner magnetic steel slot 12 is defined as the first side D1 of the through hole 14, the side of the through hole 14 close to the outer magnetic steel slot 13 is defined as the second side D2 of the through hole 14, and the area between the first side of the through hole 14 and the second side of the through hole 14 is defined as the third side D3 of the through hole 14; the side of the inner magnetic steel slot 12 close to the through hole 14 is defined as the first side B1 of the inner magnetic steel slot 12; the present application defines the angle between the second side D2 of the through hole 14 and the central unit axis 16 as γ, γ = 65° ~ 70°; the minimum distance between the second side D2 of the through hole 14 and the first side B1 of the inner magnetic steel slot 12 is c, c = 1.5 ~ 3.5 mm.

[0100] The above-mentioned constraint relationship between proportions and dimensions enables the through hole 14 to reduce torque pulsation without affecting the output torque, thereby reducing motor noise and vibration.

[0101] Example 5

[0102] like Figures 1-6 As shown, this embodiment provides a rotor punching, wherein a central axis hole 15 is provided at the center of the rotor punching; the rotor punching includes M punching units 11, and the M punching units 11 are symmetrically arranged relative to the central axis hole 15 of the rotor punching; M is an even number greater than 0; a through hole 14 is provided in the punching unit 11, and the through hole 14 is located in a high magnetic density area of ​​the punching unit 11; the high magnetic density area is located on the side of the punching unit 11 away from the central axis hole 15.

[0103] This embodiment is designed for a new energy permanent magnet synchronous drive motor with a power of 100Kw-180Kw and a stator outer diameter of 240-260mm.

[0104] like Figure 2 As shown, in the present application, the punching unit 11 is provided with an inner magnetic steel slot 12, and the inner magnetic steel slot 12 is inserted into the inner magnetic steel; the distance from the side of the inner magnetic steel slot 12 away from the central axis hole to the central axis hole 15 is R, R = (R0-1.2mm) ~ (R0-0.5mm). Figure 3As shown, the middle position of the inner magnetic steel slot 12 is a rectangular structure, and the two ends are arc-shaped structures, where the two ends refer to the two sides close to the central axis hole 15 or away from the central axis hole 15. The distance between the side of the high magnetic density area away from the central axis hole and the central axis hole 15 is R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole 15 is R2, R2 = (R-6mm) ~ (R-2.5mm); R1 = (R2+2.5mm) ~ R.

[0105] The above-mentioned size ratio relationship of the present application enables the through hole 14D to be located in the high magnetic density area at the outer end of the rotor. The existence of the through hole 14 reduces the area of ​​the high magnetic density area, thereby reducing the rotor iron loss and improving the motor efficiency.

[0106] In the present application, an outer magnetic steel slot 13 is provided on one side of the inner magnetic steel slot 12 close to the central unit axis 16. The central unit axis 16 is located at the center of the punching unit 11 and in the same direction as the radius of the punching unit 11. The through hole 14 is located between the inner magnetic steel slot 12 and the outer magnetic steel slot 13. The central unit axis 16 is defined as being located at the center of the punching unit 11 and in the same direction as the radius of the punching unit 11.

[0107] like Figure 5 and Figure 6 As shown, the length and width of the outer magnetic steel inserted into the outer magnetic steel slot 13 are 13.2 mm and 2.6 mm respectively. The width of the magnetic bridge between the two outer magnetic steel slots 13 is 1.6 mm, and the angle between the two outer magnetic steel slots 13 is 101°.

[0108] The length and width of the inner magnetic steel inserted into the inner magnetic steel slot 12 are 24.5 mm and 5.4 mm respectively. The width of the magnetic bridge between the two inner magnetic steel slots 12 is 3.5 mm, and the angle between the two inner magnetic steel slots 12 is 92°.

[0109] It should be noted that: Figure 6 As shown, in the present application, the middle position of the inner magnetic steel slot 12 is a rectangular structure, and the two ends are arc-shaped structures, wherein the two ends refer to the two sides close to the central axis hole 15 or away from the central axis hole 15. The inner magnetic steel is a rectangular structure and is inserted into the rectangular notch of the inner magnetic steel slot 12. Similarly, the middle position of the outer magnetic steel slot 13 is a rectangular structure, and the two ends are arc-shaped structures, wherein the two ends refer to the two sides close to the central axis hole 15 or away from the central axis hole 15. The outer magnetic steel is a rectangular structure and is inserted into the rectangular notch of the outer magnetic steel slot 13.

[0110] In the present application, there are two inner magnetic steel slots 12, and the two inner magnetic steel slots 12 are symmetrically distributed relative to the central unit axis 16, and the two inner magnetic steel slots 12 are V-shaped with the opening facing the outside of the punching unit 11; there are two outer magnetic steel slots 13, and the two outer magnetic steel slots 13 are symmetrically distributed relative to the central unit axis 16, and the two outer magnetic steel slots 13 are V-shaped with the opening facing the outside of the punching unit 11; there are two through holes 14, and the two through holes 14 are symmetrically distributed relative to the central unit axis 16.

[0111] In this application, the cross section of the through hole 14 is a triangle; the side of the through hole 14 close to the inner magnetic steel slot 12 is defined as the first side D1 of the through hole 14, the side of the through hole 14 close to the outer magnetic steel slot 13 is defined as the second side D2 of the through hole 14, and the area between the first side of the through hole 14 and the second side of the through hole 14 is defined as the third side D3 of the through hole 14; the side of the inner magnetic steel slot 12 close to the through hole 14 is defined as the first side B1 of the inner magnetic steel slot 12. Figure 3 and Figure 4 As shown, the present application defines the angle between the first side D1 of the through hole 14 and the first side B1 of the inner magnetic steel slot 12 as β, β = 21°~23°; the present application defines the minimum distance between the first side D1 of the through hole 14 and the first side B1 of the inner magnetic steel slot 12 as d, d = 0.7~1.2mm.

[0112] The above-mentioned limitations on the angle β and the minimum distance d can ensure that the through hole 14 is close to the inner magnetic steel slot 12 without affecting the fundamental wave, that is, without affecting the output torque, while reducing the harmonic content, thereby reducing the rotor iron loss and improving the motor efficiency.

[0113] This application specifies that the angle between the second side D2 of the through hole 14 and the central unit axis 16 is γ, where γ = 65° to 70°. The minimum distance between the second side D2 of the through hole 14 and the first side B1 of the inner magnetic steel slot 12 is c, where c = 1.5 to 3.5 mm. This ratio and size constraint allows the through hole 14 to reduce torque ripple without affecting output torque, thereby reducing motor noise and vibration.

[0114] The present application defines that the corner connection of the through hole 14 is rounded, and the radius of the rounded corner is RD, RD = 0.2-0.5 mm. The rounded corner design facilitates the processing and forming of the through hole 14 and improves the production efficiency of the rotor punching.

[0115] The motors formed by the rotor punchings without the through holes 14 and the rotor punchings with the through holes 14 in this embodiment are compared as a comparative example and an experimental example. Figure 7-Figure 9 As shown, Figure 7 Schematic diagram of the rotor lamination iron loss optimization results in the comparative example and the experimental example; Figure 8 Optimization results of rotor punching torque ripple in comparative example and experimental example; Figure 9Figure 1 shows the results of optimizing the harmonic content of the rotor laminations for the comparative example and experimental example. It can be seen that by adding through-holes 14 to the outer ends of the rotor laminations, while maintaining essentially unchanged output torque, the harmonic content is reduced by 50%, torque ripple is reduced by 27%, iron loss is reduced by 10% at full speed, and the motor's maximum efficiency is increased by 0.4%.

[0116] The present application also provides a permanent magnet synchronous drive motor, including the rotor laminations of the above-described embodiment. By providing through holes 14 in the high-magnetic-density region, the area of ​​the magnetic-density saturation region is reduced, while simultaneously reducing harmonic content, thereby reducing iron loss and improving motor efficiency. The resulting permanent magnet synchronous drive motor, while maintaining substantially unchanged output torque, reduces harmonic content by 50%, torque ripple by 27%, iron loss by 10% at full speed, and the motor's maximum efficiency by 0.4%.

[0117] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to actual proportional relationships. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as being merely exemplary and not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures. In the description of this application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of this application; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0118] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0119] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0120] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A rotor punching sheet, wherein a central axis hole (15) is provided at the center of the rotor punching sheet; the rotor punching sheet comprises M punching sheet units (11), and the M punching sheet units (11) are symmetrically arranged relative to the central axis hole (15) of the rotor punching sheet; M is an even number greater than 0; It is characterized by: A through hole (14) is provided in the punching unit (11), and the through hole (14) is located in a high magnetic density area of ​​the punching unit (11); the high magnetic density area is located on a side of the punching unit (11) away from the central axis hole (15).

2. A rotor punching according to claim 1, characterized in that: The distance between the side of the high magnetic density area away from the central axis hole and the central axis hole (15) is R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole (15) is R2, R2 = (R0-7.2mm) ~ (R0-3mm); R1 = (R2+2.5mm) ~ R, R0 is the radius of the rotor punching.

3. A rotor punching according to claim 1, characterized in that: The punching unit (11) is provided with an inner magnetic steel slot (12), and the inner magnetic steel is inserted into the inner magnetic steel slot (12); the distance from the side of the inner magnetic steel slot (12) away from the central axis hole to the central axis hole (15) is R, R = (R0-1.2mm) ~ (R0-0.5mm); The distance between the side of the high magnetic density area away from the central axis hole and the central axis hole (15) is R1, and the distance between the side of the high magnetic density area close to the central axis hole and the central axis hole (15) is R2, R2 = (R-6mm) ~ (R-2.5mm); R1 = (R2+2.5mm) ~ R.

4. A rotor punching according to claim 3, characterized in that: An outer magnetic steel slot (13) is provided on one side of the inner magnetic steel slot (12) close to the central unit axis (16), and the central unit axis (16) is located at the center of the punching unit (11) and is in the same direction as the radius of the punching unit (11); The through hole (14) is located between the inner magnetic steel slot (12) and the outer magnetic steel slot (13).

5. A rotor punching according to claim 4, characterized in that: The cross section of the through hole (14) is triangular; the side of the through hole (14) close to the inner magnetic steel slot (12) is the first side D1 of the through hole (14); the side of the through hole (14) close to the outer magnetic steel slot (13) is the second side D2 of the through hole (14); the area between the first side of the through hole (14) and the second side of the through hole (14) is the third side D3 of the through hole (14); the side of the inner magnetic steel slot (12) close to the through hole (14) is the first side B1 of the inner magnetic steel slot (12); The angle between the first side D1 of the through hole (14) and the first side B1 of the inner magnetic steel slot (12) is β. β＝21°～23°； The minimum distance between the first side D1 of the through hole (14) and the first side B1 of the inner magnetic steel slot (12) is d, d=0.7~1.2mm.

6. A rotor punching according to claim 4, characterized in that: The cross section of the through hole (14) is triangular; the side of the through hole (14) close to the inner magnetic steel slot (12) is the first side D1 of the through hole (14); the side of the through hole (14) close to the outer magnetic steel slot (13) is the second side D2 of the through hole (14); the area between the first side of the through hole (14) and the second side of the through hole (14) is the third side D3 of the through hole (14); the side of the inner magnetic steel slot (12) close to the through hole (14) is the first side B1 of the inner magnetic steel slot (12); The included angle between the second side D2 of the through hole (14) and the central unit axis (16) is γ, γ = 65° to 70°; The minimum distance between the second side D2 of the through hole (14) and the first side B1 of the inner magnetic steel slot (12) is c, where c=1.5-3.5 mm.

7. A rotor punching according to claim 5, characterized in that: The corner connection of the through hole (14) is a chamfered corner, and the radius of the chamfered corner is RD, RD=0.2-0.5mm.

8. A rotor punching according to claim 4, characterized in that: There are two inner magnetic steel slots (12), the two inner magnetic steel slots (12) are symmetrically distributed relative to the central unit axis (16), and the two inner magnetic steel slots (12) are distributed in a V-shape with their openings facing the outside of the punching unit (11); There are two outer magnetic steel slots (13), the two outer magnetic steel slots (13) are symmetrically distributed relative to the central unit axis (16), and the two outer magnetic steel slots (13) are distributed in a V-shape with their openings facing the outside of the punching unit (11); There are two through holes (14), and the two through holes (14) are symmetrically distributed relative to the central unit axis (16).

9. A rotor punching according to claim 1, characterized in that: The radius of the rotor punching is 240-260 mm.

10. A permanent magnet synchronous drive motor, characterized in that: A rotor punching comprising the rotor punching according to any one of claims 1 to 9.

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