Rotor punching sheet, rotor magnetic circuit structure and driving motor
By designing a rotor punching piece with abolished magnetic bridge structure and installing surface-mounted and embedded permanent magnets in the permanent magnet motor, the problems of magnetic leakage and low material utilization in the development of high-speed and high power density are solved, and more efficient motor performance is achieved.
Patent Information
- Application Number
- CN202421616544.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-09
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-07-09
AI Technical Summary
In the process of high-speed and high power density, permanent magnet motors have low magnetic resistance torque utilization and low power density, and the embedded rotor magnetic circuit structure has a large magnetic leakage and low material utilization.
A rotor punching piece is designed, including a punching piece body and a punching piece combination portion distributed around the punching piece body, cancel the magnetic isolation bridge structure, connect the intermediate punching piece and the punching piece body through the connecting rib, and insert surface-mounted and embedded permanent magnets in the magnetic steel trough to form a hybrid magnetic circuit structure.
Effectively reduce magnetic leakage, improve material utilization and motor efficiency, and achieve higher speed and higher power density motor performance.
Smart Images
Figure CN222953785U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of motors, and in particular to a rotor punching sheet, a rotor magnetic circuit structure and a driving motor. Background Art
[0002] As one of the core components of the automotive electrification system, permanent magnet motors have been widely used due to their high power density, high efficiency and low noise. The rotor magnetic circuit structure design of permanent magnet motors is strongly correlated with the performance of the entire machine.
[0003] Permanent magnet motors are developing towards high power density and high speed. Although permanent magnet motors use a surface-mounted rotor magnetic circuit structure to achieve high speed, the utilization rate of the reluctance torque is low and the power density is low.
[0004] The permanent magnet motor uses an embedded rotor magnetic circuit structure to improve the power density to a certain extent. However, due to the existence of the magnetic bridge in the rotor punching, and the fact that the magnetic bridge is usually made thicker to resist rotor deformation at high speed, this increases the leakage magnetic path of the permanent magnet itself, resulting in larger leakage magnetic field and low material utilization, which limits the ability to achieve high speed and high power density. Utility Model Content
[0005] The purpose of the utility model is to provide a rotor punching, rotor magnetic circuit structure and drive motor that can effectively improve the leakage magnetic field problem and improve the rotor excitation magnetic field energy and the stability of the motor rotor structure, so as to facilitate the development needs of higher speed and higher power density of the motor.
[0006] The technical solution of the utility model is:
[0007] A rotor punching sheet includes a punching sheet body and a plurality of punching sheet assembly parts distributed circumferentially around the punching sheet body, the punching sheet assembly part includes an edge punching sheet and an intermediate punching sheet located between the edge punching sheet and the punching sheet body, the edge punching sheet and the intermediate punching sheet are disconnected, the intermediate punching sheet and the punching sheet body are connected by connecting ribs, a first magnetic steel slot is provided on the outer edge of the edge punching sheet, a second magnetic steel slot is provided between the edge punching sheet and the intermediate punching sheet, and a third magnetic steel slot is provided between the punching sheet body and the intermediate punching sheet. In the punching sheet assembly part of the rotor punching sheet of this scheme, the edge punching sheet and the intermediate punching sheet are disconnected, and the intermediate punching sheet and the punching sheet body are connected by connecting ribs, thereby eliminating the magnetic isolation bridge structure, reducing magnetic leakage, effectively improving the magnetic leakage problem, thereby improving material utilization, and improving its motor efficiency and output torque capacity. On the other hand, the first magnetic steel slot, the second magnetic steel slot and the third magnetic steel slot can all be embedded with permanent magnets. The permanent magnets in the first magnetic steel slot are surface-mounted permanent magnets, and the permanent magnets in the second magnetic steel slot and the third magnetic steel slot are embedded permanent magnets. Therefore, a mixed magnetic circuit structure of surface-mounted and embedded types can be formed, thereby increasing the rotor excitation magnetic field energy within a limited space, achieving high speed while greatly improving the power density of the motor.
[0008] Preferably, there are one or more intermediate punching sheets;
[0009] When there are multiple intermediate punching sheets, the multiple intermediate punching sheets are sequentially distributed along the radial direction of the rotor punching sheets, and an intermediate magnetic steel slot is formed between any two adjacent intermediate punching sheets, and any two adjacent intermediate punching sheets are connected by connecting ribs, the first magnetic steel slot is located between the edge punching sheet and the adjacent intermediate punching sheet, and the third magnetic steel slot is located between the punching sheet body and the adjacent intermediate punching sheet. In this way, when there are multiple intermediate punching sheets, permanent magnets can be embedded in the intermediate magnetic steel slots, thereby further improving the rotor excitation magnetic field energy within a limited space range and improving the power density of the motor.
[0010] Preferably, the middle magnetic steel slot passes through the edge of the rotor punching sheet. In this way, the middle magnetic steel slot has no magnetic isolation bridge structure, which can reduce magnetic leakage and effectively improve the magnetic leakage problem.
[0011] Preferably, the second magnetic steel slot and the third magnetic steel slot both pass through the edge of the rotor punching.
[0012] Preferably, the second magnetic steel slot includes at least two embedding slots in which magnetic steel can be embedded, and any two adjacent embedding slots in the second magnetic steel slot are connected through a connecting slot. A permanent magnet can be embedded in each embedding slot, so that the rotor excitation magnetic field energy within a limited space can be further increased, thereby improving the power density of the motor.
[0013] Preferably, the third magnetic steel slot includes at least two embedding slots in which magnetic steel can be embedded, and any two adjacent embedding slots in the third magnetic steel slot are separated by connecting ribs. A permanent magnet can be embedded in each embedding slot, so that the rotor excitation magnetic field energy within a limited space can be further increased, thereby improving the power density of the motor.
[0014] Preferably, a weight-reducing hole is provided on the punching sheet body, so that the weight of the punching sheet body can be reduced, so that the rotor core can achieve a lightweight effect.
[0015] A rotor magnetic circuit structure includes rotor punchings, a plurality of the rotor punchings are stacked to form a rotor core, at least one permanent magnet is embedded in each of the first magnetic steel slot, the second magnetic steel slot and the third magnetic steel slot, the outer periphery of the rotor core is coated with a limiting element, and the edge punchings and the permanent magnets in the first magnetic steel slot are tightly fitted with the limiting element. The rotor magnetic circuit structure of this scheme uses limiting elements to coat the outer periphery of the rotor core, which can effectively improve the strength and stability of the motor rotor structure, so as to facilitate the development needs of higher speed and higher power density of the motor. At the same time, the permanent magnets in the first magnetic steel slot are surface-mounted permanent magnets, and the permanent magnets in the second magnetic steel slot and the third magnetic steel slot are embedded permanent magnets, so that a surface-mounted and embedded mixed magnetic circuit structure can be formed, thereby improving the rotor excitation magnetic field energy within a limited space, achieving high speed while greatly improving the power density of the motor.
[0016] Preferably, one permanent magnet is embedded in the first magnetic steel slot, two permanent magnets are embedded in the second magnetic steel slot, and three permanent magnets are embedded in the third magnetic steel slot. In this way, the energy of the rotor excitation magnetic field within a limited space can be further increased, thereby improving the power density of the motor.
[0017] A driving motor comprises a rotor magnetic circuit structure.
[0018] The beneficial effects of the utility model are: it can effectively improve the leakage magnetic field problem, and can improve the rotor excitation magnetic field energy and the stability of the motor rotor structure, so as to facilitate the development needs of higher speed and higher power density of the motor. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a top view of the rotor punching sheet of the specific embodiment 1 of the utility model.
[0020] Figure 2 It is a top view of the rotor punching sheet of the specific embodiment 2 of the utility model.
[0021] Figure 3 It is a top view of the rotor magnetic circuit structure of the specific embodiment 3 of the present utility model.
[0022] In the figure:
[0023] Punch body 1, weight-reducing hole 1.1;
[0024] Punching sheet assembly part 2, edge punching sheet 2.1, middle punching sheet 2.2, connecting rib 2.3;
[0025] First magnetic steel slot 3;
[0026] Second magnetic steel slot 4;
[0027] The third magnetic steel slot 5;
[0028] Middle magnetic steel slot 6;
[0029] permanent magnet 7;
[0030] Limiting element 8. DETAILED DESCRIPTION
[0031] Specific embodiment 1, as Figure 1 As shown, a rotor punching sheet comprises a punching sheet body 1 and a plurality of punching sheet assembly parts 2 uniformly distributed around the punching sheet body 1 in the circumferential direction.
[0032] The punch assembly 2 includes an edge punch 2.1 and an intermediate punch 2.2 located between the edge punch 2.1 and the punch body 1. In this embodiment, there is one intermediate punch 2.2. The edge punch 2.1 and the intermediate punch 2.2 are disconnected, and the intermediate punch 2.2 and the punch body 1 are connected by a connecting rib 2.3.
[0033] A first magnetic steel slot 3 is provided on the outer edge of the edge punching sheet 2.1. The outer edge of the edge punching sheet 2.1 refers to the edge of the edge punching sheet 2.1 on one side facing away from the middle punching sheet 2.2. A second magnetic steel slot 4 is provided between the edge punching sheet 2.1 and the middle punching sheet 2.2. A third magnetic steel slot 5 is provided between the punching sheet body 1 and the middle punching sheet 2.2. Both the second magnetic steel slot 4 and the third magnetic steel slot 5 penetrate the edge of the rotor punching sheet so that the rotor punching sheet has no magnetic bridge structure.
[0034] In the rotor punching of the present embodiment, the edge punching 2.1 and the middle punching 2.2 are disconnected, the middle punching 2.2 and the punching body 1 are connected by the connecting rib 2.3, and the second magnetic steel slot 4 and the third magnetic steel slot 5 both pass through the edge of the rotor punching, thereby eliminating the magnetic isolation bridge structure, reducing magnetic leakage, and effectively improving the magnetic leakage problem, thereby improving material utilization, and improving its motor efficiency and output torque capacity.
[0035] On the other hand, the first magnetic steel slot 3, the second magnetic steel slot 4 and the third magnetic steel slot 5 can all be embedded with permanent magnets 7, wherein the permanent magnet 7 in the first magnetic steel slot 3 is a surface-mounted permanent magnet 7, and the permanent magnets 7 in the second magnetic steel slot 4 and the third magnetic steel slot 5 are embedded permanent magnets 7, thereby forming a magnetic circuit structure that is a mixture of surface-mounted and embedded types, thereby increasing the rotor excitation magnetic field energy within a limited space, achieving high speed while greatly improving the power density of the motor.
[0036] Further, the second magnetic steel slot 4 includes at least two embedding slots in which magnetic steel can be embedded, and any two adjacent embedding slots in the second magnetic steel slot 4 are connected by a connecting slot. In this embodiment, the second magnetic steel slot 4 includes two embedding slots in which magnetic steel can be embedded. A permanent magnet 7 can be embedded in each embedding slot, so that the rotor excitation magnetic field energy within a limited space can be further improved, thereby improving the power density of the motor.
[0037] The third magnetic steel slot 5 includes at least two embedding slots in which magnetic steel can be embedded, and any two adjacent embedding slots in the third magnetic steel slot 5 are separated by a connecting rib 2.3. In this embodiment, the third magnetic steel slot 5 includes three embedding slots in which magnetic steel can be embedded. A permanent magnet 7 can be embedded in each embedding slot, so that the rotor excitation magnetic field energy within a limited space can be further improved, thereby improving the power density of the motor.
[0038] Furthermore, a weight-reducing hole 1.1 is provided on the punching sheet body 1. There are one or more weight-reducing holes 1.1. In this embodiment, there are multiple weight-reducing holes 1.1, and each weight-reducing hole 1.1 is evenly distributed around the center of the punching sheet body 1. In this way, the weight of the punching sheet body 1 can be reduced, so that the rotor core can achieve a lightweight effect.
[0039] Specific embodiment 2, as Figure 2 As shown, a rotor punching sheet comprises a punching sheet body 1 and a plurality of punching sheet assembly parts 2 uniformly distributed around the punching sheet body 1 in the circumferential direction.
[0040] The punching sheet assembly 2 includes an edge punching sheet 2.1 and an intermediate punching sheet 2.2 located between the edge punching sheet 2.1 and the punching sheet body 1. There are multiple intermediate punching sheets 2.2 (for example, there are 2-5 intermediate punching sheets 2.2), and the multiple intermediate punching sheets 2.2 are sequentially distributed along the radial direction of the rotor punching sheet, and an intermediate magnetic steel groove 6 is formed between any two adjacent intermediate punching sheets 2.2, and any two adjacent intermediate punching sheets 2.2 are connected by a connecting rib 2.3. In this embodiment, there are two intermediate punching sheets 2.2.
[0041] The edge punching sheet 2.1 is disconnected from an adjacent middle punching sheet 2.2, and the punching sheet body 1 is connected to an adjacent middle punching sheet 2.2 via a connecting rib 2.3.
[0042] A first magnetic steel slot 3 is provided on the outer edge of the edge punching sheet 2.1. The outer edge of the edge punching sheet 2.1 refers to the edge of the edge punching sheet 2.1 facing away from the middle punching sheet 2.2. A second magnetic steel slot 4 is provided between the edge punching sheet 2.1 and an adjacent middle punching sheet 2.2. A third magnetic steel slot 5 is provided between the punching sheet body 1 and an adjacent middle punching sheet 2.2. The second magnetic steel slot 4 and the third magnetic steel slot 5 both penetrate the edge of the rotor punching sheet, and the middle magnetic steel slot 6 penetrates the edge of the rotor punching sheet, so that the rotor punching sheet has no magnetic bridge structure.
[0043] In the rotor punching of the present embodiment, the edge punching 2.1 and the middle punching 2.2 are disconnected, the middle punching 2.2 is connected to the punching body 1 by the connecting rib 2.3, the middle punchings 2.2 are connected by the connecting rib 2.3, the second magnetic steel slot 4 and the third magnetic steel slot 5 both pass through the edge of the rotor punching, and the middle magnetic steel slot 6 passes through the edge of the rotor punching, thereby eliminating the magnetic isolation bridge structure, reducing magnetic leakage, and effectively improving the magnetic leakage problem, thereby improving material utilization, and improving its motor efficiency and output torque capacity.
[0044] On the other hand, the first magnetic steel slot 3, the second magnetic steel slot 4, the third magnetic steel slot 5 and the middle magnetic steel slot can all be embedded with permanent magnets 7, among which the permanent magnet 7 of the first magnetic steel slot 3 is a surface-mounted permanent magnet 7, and the permanent magnets 7 in the middle magnetic steel slot 6, the second magnetic steel slot 4 and the third magnetic steel slot 5 are embedded permanent magnets 7, thereby forming a magnetic circuit structure that is a mixture of surface-mounted and embedded types, thereby increasing the rotor excitation magnetic field energy within a limited space, achieving high speed while greatly improving the power density of the motor.
[0045] Further, the second magnetic steel slot 4 includes at least two embedding slots in which magnetic steel can be embedded, and any two adjacent embedding slots in the second magnetic steel slot 4 are connected by a connecting slot. In this embodiment, the second magnetic steel slot 4 includes two embedding slots in which magnetic steel can be embedded. A permanent magnet 7 can be embedded in each embedding slot, so that the rotor excitation magnetic field energy within a limited space can be further improved, thereby improving the power density of the motor.
[0046] The third magnetic steel slot 5 includes at least two embedding slots in which magnetic steel can be embedded, and any two adjacent embedding slots in the third magnetic steel slot 5 are separated by a connecting rib 2.3. In this embodiment, the third magnetic steel slot 5 includes three embedding slots in which magnetic steel can be embedded. A permanent magnet 7 can be embedded in each embedding slot, so that the rotor excitation magnetic field energy within a limited space can be further improved, thereby improving the power density of the motor.
[0047] The middle magnetic steel slot 6 includes at least two embedding slots in which magnetic steel can be embedded, and any two adjacent embedding slots in the middle magnetic steel slot are separated by a connecting rib 2.3. In this embodiment, the middle magnetic steel slot includes three embedding slots in which magnetic steel can be embedded. A permanent magnet 7 can be embedded in each embedding slot, so that the rotor excitation magnetic field energy within a limited space can be further increased, thereby improving the power density of the motor.
[0048] Furthermore, a weight-reducing hole 1.1 is provided on the punching sheet body 1. There are one or more weight-reducing holes 1.1. In this embodiment, there are multiple weight-reducing holes 1.1, and each weight-reducing hole 1.1 is evenly distributed around the center of the punching sheet body 1. In this way, the weight of the punching sheet body 1 can be reduced, so that the rotor core can achieve a lightweight effect.
[0049] Specific embodiment 3, a rotor magnetic circuit structure, including a rotor punching. The specific structure of the rotor punching of this embodiment refers to specific embodiment 1.
[0050] like Figure 3 As shown, a plurality of the rotor punching sheets are stacked to form a rotor core. At least one permanent magnet 7 is embedded in each of the first magnetic steel slot 3, the second magnetic steel slot 4 and the third magnetic steel slot 5. The outer periphery of the rotor core is coated with a limiting element 8. The edge punching sheet 2.1 and the permanent magnet 7 in the first magnetic steel slot 3 fit closely with the limiting element 8. The rotor magnetic circuit structure of this embodiment uses a limiting element 8 to coat the outer periphery of the rotor core, which can effectively improve the strength and stability of the motor rotor structure, so as to facilitate the development needs of higher speed and higher power density of the motor. At the same time, the permanent magnet 7 in the first magnetic steel slot 3 is a surface-mounted permanent magnet 7, and the permanent magnet 7 in the second magnetic steel slot 4 and the third magnetic steel slot 5 is an embedded permanent magnet 7, so that a surface-mounted and embedded mixed magnetic circuit structure can be formed, thereby increasing the rotor excitation magnetic field energy within a limited space range, achieving high speed while greatly improving the power density of the motor.
[0051] In one implementation of this embodiment, the limiting element 8 is a band-shaped limiting element 8 that surrounds the periphery of the rotor core, thereby covering the periphery of the rotor core and improving the structural strength and stability of the motor rotor.
[0052] In another implementation manner of this embodiment, the limiting element 8 is in the shape of a sleeve, and the limiting element 8 is sleeved on the periphery of the rotor core, thereby covering the periphery of the rotor core and improving the structural strength and stability of the motor rotor.
[0053] In this embodiment, the material of the limiting element 8 includes but is not limited to carbon fiber materials.
[0054] In this embodiment, a permanent magnet 7 is embedded in the first magnetic steel slot 3. Two permanent magnets 7 are embedded in the second magnetic steel slot 4, and the two permanent magnets 7 embedded in the second magnetic steel slot 4 have the same shape and size. Three permanent magnets 7 are embedded in the third magnetic steel slot 5, and the three permanent magnets 7 embedded in the third magnetic steel slot 5 have the same shape and size. In this way, the rotor excitation magnetic field energy within a limited space can be further improved, and the power density of the motor can be improved. In this embodiment, the shapes and sizes of the permanent magnets 7 embedded in the second magnetic steel slot 4 and the third magnetic steel slot 5 are the same. Of course, it should be noted that the permanent magnets 7 embedded in the first magnetic steel slot 3, the second magnetic steel slot 4 and the third magnetic steel slot 5 can also be set to different shapes and sizes according to specific needs; the number of permanent magnets 7 embedded in the first magnetic steel slot 3, the second magnetic steel slot 4 and the third magnetic steel slot 5 is also set according to specific needs.
[0055] Specific embodiment 4, a rotor magnetic circuit structure, including a rotor punching. The specific structure of the rotor punching of this embodiment refers to specific embodiment 2.
[0056] A plurality of the rotor punching sheets are stacked to form a rotor core. At least one permanent magnet 7 is embedded in each of the first magnetic steel slot 3, the second magnetic steel slot 4, the third magnetic steel slot 5 and the middle magnetic steel slot 6. The outer periphery of the rotor core is covered with a limiting element 8. The edge punching sheet 2.1 and the permanent magnet 7 in the first magnetic steel slot 3 are tightly fitted with the limiting element 8 (see Figure 3 ). The rotor magnetic circuit structure of this embodiment adopts a limiting element 8 to cover the periphery of the rotor core, which can effectively improve the strength and stability of the motor rotor structure, so as to facilitate the development needs of higher speed and higher power density of the motor. At the same time, the permanent magnet 7 of the first magnetic steel slot 3 is a surface-mounted permanent magnet 7, and the permanent magnet 7 in the second magnetic steel slot 4 and the third magnetic steel slot 5 is an embedded permanent magnet 7, so that a surface-mounted and embedded mixed magnetic circuit structure can be formed, thereby improving the rotor excitation magnetic field energy within a limited space, achieving high speed while greatly improving the power density of the motor.
[0057] In one implementation of this embodiment, the limiting element is a belt-shaped limiting element that surrounds the periphery of the rotor core, thereby covering the periphery of the rotor core and improving the structural strength and stability of the motor rotor.
[0058] In another implementation manner of this embodiment, the limiting element is in the shape of a sleeve, and the limiting element is sleeved on the periphery of the rotor core, thereby covering the periphery of the rotor core and improving the structural strength and stability of the motor rotor.
[0059] The material of the limiting element in this embodiment includes but is not limited to carbon fiber materials.
[0060] In this embodiment, a permanent magnet is embedded in the first magnetic steel slot. Two permanent magnets are embedded in the second magnetic steel slot, and the two permanent magnets embedded in the second magnetic steel slot have the same shape and size. Three permanent magnets are embedded in the third magnetic steel slot, and the three permanent magnets embedded in the third magnetic steel slot have the same shape and size. Three permanent magnets are embedded in the middle magnetic steel slot, and the three permanent magnets embedded in the middle magnetic steel slot have the same shape and size. In this way, the rotor excitation magnetic field energy within a limited space can be further improved, and the power density of the motor can be improved. In this embodiment, the shapes and sizes of the permanent magnets embedded in the second magnetic steel slot and the third magnetic steel slot are the same. Of course, it should be noted that the permanent magnets embedded in the first magnetic steel slot, the second magnetic steel slot, the third magnetic steel slot and the middle magnetic steel slot can also be set to different shapes and sizes according to specific needs; the number of permanent magnets embedded in the first magnetic steel slot, the second magnetic steel slot, the third magnetic steel slot and the middle magnetic steel slot is also set according to specific needs.
[0061] Specific embodiment 5, a driving motor includes a rotor magnetic circuit structure. The specific structure of the rotor magnetic circuit structure of this embodiment refers to specific embodiment 3 or specific embodiment 4.
[0062] The above description is only a preferred embodiment of the present invention and does not constitute any limitation to the present invention. Any simple modification, change and equivalent transformation made to the above embodiments according to the technical essence of the present invention shall still fall within the protection scope of the technical solution of the present invention.
Claims
1. A rotor punching, characterized in that: It includes a punching sheet body and a plurality of punching sheet assembly parts distributed circumferentially around the punching sheet body, the punching sheet assembly part includes an edge punching sheet and an intermediate punching sheet located between the edge punching sheet and the punching sheet body, the edge punching sheet and the intermediate punching sheet are disconnected, the intermediate punching sheet and the punching sheet body are connected by connecting ribs, a first magnetic steel groove is provided on the outer edge of the edge punching sheet, a second magnetic steel groove is provided between the edge punching sheet and the intermediate punching sheet, and a third magnetic steel groove is provided between the punching sheet body and the intermediate punching sheet.
2. A rotor punching according to claim 1, characterized in that: The number of the intermediate punching sheets is one or more; When there are multiple intermediate punching sheets, the multiple intermediate punching sheets are distributed in sequence along the radial direction of the rotor punching sheets, and an intermediate magnetic steel groove is formed between any two adjacent intermediate punching sheets. Any two adjacent intermediate punching sheets are connected by connecting ribs. The first magnetic steel groove is located between the edge punching sheet and the adjacent intermediate punching sheet, and the third magnetic steel groove is located between the punching sheet body and the adjacent intermediate punching sheet.
3. A rotor punching according to claim 2, characterized in that: The middle magnetic steel slot passes through the edge of the rotor punching sheet.
4. A rotor punching according to claim 1, 2 or 3, characterized in that: The second magnetic steel slot and the third magnetic steel slot both penetrate the edge of the rotor punching sheet.
5. A rotor punching according to claim 1, 2 or 3, characterized in that: The second magnetic steel slot includes at least two embedding slots into which the magnetic steel can be embedded, and any two adjacent embedding slots in the second magnetic steel slot are connected via a connecting slot.
6. A rotor punching according to claim 1, 2 or 3, characterized in that: The third magnetic steel slot includes at least two embedding slots in which magnetic steel can be embedded, and any two adjacent embedding slots in the third magnetic steel slot are separated by connecting ribs.
7. A rotor punching according to claim 1, 2 or 3, characterized in that: The punch body is provided with a weight-reducing hole.
8. A rotor magnetic circuit structure, characterized in that: The rotor punching comprises the rotor punching described in any one of claims 1 to 7, wherein a plurality of the rotor punchings are stacked to form a rotor core, wherein at least one permanent magnet is respectively embedded in the first magnetic steel slot, the second magnetic steel slot and the third magnetic steel slot, and the periphery of the rotor core is wrapped with a limiting element, and the edge punching and the permanent magnet in the first magnetic steel slot are tightly fitted with the limiting element.
9. The rotor magnetic circuit structure according to claim 8, characterized in that: One permanent magnet is embedded in the first magnetic steel slot, two permanent magnets are embedded in the second magnetic steel slot, and three permanent magnets are embedded in the third magnetic steel slot.
10. A driving motor, characterized in that: It includes the rotor magnetic circuit structure as described in claim 8 or 9.