A built-in low-leakage permanent magnet motor rotor

Abstract

The present invention discloses a built-in low-leakage permanent magnet motor rotor, comprising an iron core and a plurality of magnetic steels, wherein the iron core has a central axial hole; a plurality of magnetic steel slot groups are arranged around the iron core, each magnetic steel slot group comprises a plurality of magnetic steel slots distributed along the radial direction of the iron core; each group of magnetic steel slots distributed in an "eight" shape comprises two magnetic steel slots symmetrically distributed along the radial direction of the iron core; a matching magnetic steel is embedded in each magnetic steel slot; and a limiting structure is provided at the outer end of the magnetic steel slot. The present invention can solve the problem of deformation or damage of the rotor iron core due to excessive centrifugal force when the built-in motor rotor is running at high speed, and improve the stability of the motor.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a built-in low-leakage magnetic permanent magnet motor rotor. Background Art

[0002] Built-in permanent magnet motors are characterized by small size, high power density and high efficiency, and are widely used in new energy vehicles. In order to reduce magnetic leakage and improve motor performance, as well as reduce the amount of magnetic steel used to save costs, the magnetic isolation bridge on the outer edge of the rotor will be made very narrow or the rotor core will be divided into inner and outer cores and the magnetic isolation bridge will be completely disconnected to meet performance requirements. The disconnection of the outer edge magnetic isolation bridge will increase motor losses (oil throwing and wind friction), which will have a great impact on the efficiency when the motor is running. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a built-in low-leakage permanent magnet motor rotor, which can solve the problem of reduced efficiency due to excessive loss during operation of the built-in motor rotor and improve the performance and stability of the motor.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: a built-in low-leakage permanent magnet motor rotor, including an iron core and a plurality of magnetic steels, wherein the iron core has a central axial hole; characterized in that: a plurality of groups of magnetic steel slot groups are arranged around the iron core, and the plurality of groups of magnetic steel slot groups are centrally symmetrically distributed around the axis of the iron core; each group of magnetic steel slot groups includes a plurality of groups of magnetic steel slots distributed in an "eight" shape along the radial direction of the iron core; each group of magnetic steel slots distributed in an "eight" shape includes two magnetic steel slots distributed symmetrically along the radial direction of the iron core, and there is a spacing between the ends of the two magnetic steel slots close to the axial hole to form a magnetic isolation bridge; wherein the outer ends of the magnetic steel slots penetrate the side wall of the iron core, and the spacing between the outer ends of the two magnetic steel slots is greater than the spacing between the inner ends of the two magnetic steel slots; a matching magnetic steel is embedded in each magnetic steel slot; and a limiting structure is also provided at the outer end of the magnetic steel slot.

[0005] Furthermore, the limiting structure is formed by filling with injection molding material.

[0006] Furthermore, each group of magnetic steel slots includes two groups of magnetic steel slots distributed in an "eight" shape along the radial direction of the iron core.

[0007] Furthermore, the inner end of the magnetic steel slot is a contraction structure, so that there is a distance between the inner end of the magnetic steel and the inner end of the magnetic steel slot.

[0008] Furthermore, an injection molding material is filled between the inner end of the magnetic steel and the inner end of the magnetic steel slot.

[0009] Compared with the prior art, the present invention has the following advantages: simple structure. By adopting this solution, under the condition of the same output torque, the amount of magnetic steel used can be reduced, thereby improving the weight reduction ratio and power density of the motor and optimizing the motor performance. Moreover, it has a wide range of applications and can be used for partial magnetic isolation bridge structures. It can reduce leakage magnetic flux, thereby ensuring the performance of the motor and improving the stability and service life of the motor rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural schematic diagram of the present invention.

[0011] Figure 2 for Figure 1 Top view of the .

[0012] Figure 3 It is a top view of the iron core in the present invention.

[0013] In the figure: 1—iron core, 2—magnetic steel, 3—axial hole, 4—magnetic steel slot, 5—limiting structure, 6—first magnetic isolation bridge, 7—second magnetic isolation bridge. DETAILED DESCRIPTION

[0014] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0015] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0017] Example: See Figure 1 , Figure 2 as well as Figure 3 A built-in low-leakage permanent magnet motor rotor includes an iron core 1 and a plurality of magnetic steels 2, wherein the iron core 1 has a central axial hole 3. A plurality of magnetic steel slot groups are arranged around the iron core 1, and the plurality of magnetic steel slot groups are centrally symmetrically distributed around the axis of the iron core 1. Each magnetic steel slot group includes a plurality of magnetic steel slots 4 distributed in an "eight" shape along the radial direction of the iron core 1.

[0018] Each group of magnetic steel slots 4 distributed in an "eight" shape includes two magnetic steel slots 4 distributed symmetrically along the radial direction of the iron core 1, and there is a distance between the ends of the two magnetic steel slots 4 close to the shaft hole 3 to form a magnetic isolation bridge. Among them, the outer ends of the magnetic steel slots 4 (the ends away from the shaft hole 3) all penetrate the side wall of the iron core 1, and the distance between the outer ends of the two magnetic steel slots 4 is greater than the distance between the inner ends of the two magnetic steel slots 4 (the ends close to the shaft hole 3). The inner end of the magnetic steel slot 4 is a contraction structure, so that there is a distance between the inner end of the magnetic steel 2 and the inner end of the magnetic steel slot 4; injection molding material is filled between the inner end of the magnetic steel 2 and the inner end of the magnetic steel slot 4. A matching magnetic steel 2 is embedded in each magnetic steel slot 4; and a limiting structure 5 is also provided at the outer end of the magnetic steel slot 4. During implementation, the limiting structure 5 is formed by filling with injection molding material. By filling the injection molding material at the inner and outer ends of the magnetic steel slot 4, the position of the magnetic steel 2 is fixed, which can reduce mechanical loss and make the motor run smoothly.

[0019] As an implementation method, each group of magnetic steel slots includes two groups of magnetic steel slots 4 distributed in an "eight" shape along the radial direction of the iron core 1. Among them, a first magnetic isolation bridge 6 is formed between the inner ends of the two magnetic steel slots 4 close to the outer side of the iron core 1, and a second magnetic isolation bridge 7 is formed between the inner ends of the two magnetic steel slots 4 close to the inner side of the iron core 1.

[0020] This solution can be used for permanent magnet motor rotor structures without an outer edge magnetic isolation bridge structure to effectively protect the motor rotor. By setting a first magnetic isolation bridge 6 and a second magnetic isolation bridge 7 on the rotor core 1 and adding a magnetic steel slot 4 limiting structure 5, mechanical losses are reduced. At the same time, after disconnecting the outer edge magnetic isolation bridge, the effective magnetic flux of the permanent magnet is increased, thereby reducing leakage flux and improving motor performance and stability.

[0021] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the technical solution. Those skilled in the art should understand that those modifications or equivalent substitutions of the technical solution of the present invention that do not depart from the purpose and scope of the technical solution should be included in the scope of the claims of the present invention.

Claims

1. A built-in low-leakage permanent magnet motor rotor, comprising an iron core and a plurality of magnetic steels, wherein the iron core has a central axial hole; characterized in that: A plurality of magnetic steel slot groups are arranged around the iron core, and the plurality of magnetic steel slot groups are centrally symmetrically distributed around the axis of the iron core; each group of magnetic steel slot groups includes a plurality of magnetic steel slots distributed in an "eight" shape along the radial direction of the iron core; each group of magnetic steel slots distributed in an "eight" shape includes two magnetic steel slots distributed symmetrically along the radial direction of the iron core, and a spacing is provided between the ends of the two magnetic steel slots close to the shaft hole to form a magnetic isolation bridge; wherein the outer ends of the magnetic steel slots penetrate the side wall of the iron core, and the spacing between the outer ends of the two magnetic steel slots is greater than the spacing between the inner ends of the two magnetic steel slots; a matching magnetic steel is embedded in each magnetic steel slot; and a limiting structure is also provided at the outer end of the magnetic steel slot.

2. The internal low-leakage permanent magnet motor rotor according to claim 1, characterized in that: The limiting structure is formed by filling with injection molding material.

3. The internal low-leakage permanent magnet motor rotor according to claim 1, characterized in that: Each group of magnetic steel slots includes two groups of magnetic steel slots distributed in an "eight" shape along the radial direction of the iron core.

4. The internal low-leakage permanent magnet motor rotor according to claim 1, characterized in that: The inner end of the magnetic steel slot is a contraction structure, so that there is a distance between the inner end of the magnetic steel and the inner end of the magnetic steel slot.

5. The internal low-leakage permanent magnet motor rotor according to claim 4, characterized in that: The space between the inner end of the magnetic steel and the inner end of the magnetic steel slot is filled with injection molding material.

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