CN-224218167-U - Motor rotor and permanent magnet synchronous motor

Abstract

A motor rotor and a permanent magnet synchronous motor comprise a rotor core, at least two stages of permanent magnet assemblies, wherein each permanent magnet assembly comprises a plurality of radial magnetizing permanent magnets arranged on the outer side of the circumference of the rotor core, a plurality of circumferential magnetizing permanent magnets arranged on the outer side of the circumference of the rotor core, and the circumferential magnetizing permanent magnets and the radial magnetizing permanent magnets are alternately arranged in the circumferential direction, a first groove is formed in the axial end face of each radial magnetizing permanent magnet, a second groove is formed in the axial end face of each circumferential magnetizing permanent magnet, and injection molding bodies are filled in the first groove and the second groove to fix the rotor core and the permanent magnet assemblies together, and the first groove and the second groove are at least partially staggered in the circumferential direction.

Inventors

• LI SHIWEI
• SUN XIANNIAN
• Ben Zhihua

Assignees

• 浙江智源智控科技股份有限公司

Dates

Publication Date

20260508

Application Date

20250527

Claims (10)

1. 1. An electric motor rotor, comprising: a rotor core; at least two-stage permanent magnet assembly arranged in an axial direction, the permanent magnet assembly comprising: -a plurality of radially magnetizing permanent magnets arranged circumferentially outside the rotor core, the radially magnetizing permanent magnets generating a magnetic field in a substantially radial direction; -a plurality of circumferentially-magnetized permanent magnets arranged circumferentially outward of the rotor core, the circumferentially-magnetized permanent magnets generating a magnetic field in a substantially circumferential direction, the circumferentially-magnetized permanent magnets being alternately arranged with the radially-magnetized permanent magnets in the circumferential direction; The rotor core is provided with a first permanent magnet assembly, a second permanent magnet assembly and a first permanent magnet assembly, wherein a first groove extending along the circumferential direction is formed in the axial end face of the radial magnetizing permanent magnet, a second groove extending along the circumferential direction is formed in the axial end face of the circumferential magnetizing permanent magnet, and an injection molding body is filled in the rotor core and extends into the first groove and the second groove so as to fix the rotor core and the permanent magnet assembly together; And wherein the first groove is at least partially offset from the second groove in the circumferential direction.
2. 2. The motor rotor of claim 1, wherein the first groove is located outside the second groove in a radial direction.
3. 3. The electric machine rotor of claim 2, wherein the first groove communicates with the second groove in a circumferential direction.
4. 4. A motor rotor as claimed in claim 3, wherein the radial-magnetization permanent magnet has, in order from a radial inner side to a radial outer side, a first flat surface, a first concave portion recessed toward an axial inner side of the radial-magnetization permanent magnet with respect to the first flat surface, and a first protruding portion protruding toward an axial outer side of the radial-magnetization permanent magnet with respect to the first flat surface, the first concave portion forming the first groove.
5. 5. A motor rotor as claimed in claim 3, wherein the circumferential magnetization permanent magnet has a second flat surface, a second concave portion and a second protruding portion in this order from a radially inner side to a radially outer side, the second concave portion being recessed toward an axially inner side of the circumferential magnetization permanent magnet with respect to the second flat surface, the second protruding portion protruding toward an axially outer side of the circumferential magnetization permanent magnet with respect to the second flat surface, the second concave portion forming the second groove.
6. 6. The electric machine rotor of claim 1, wherein a ratio of a width of the first groove to a width of the radially magnetized permanent magnet is between 0.15 and 0.18.
7. 7. The electric machine rotor of claim 1, wherein a ratio of a distance between a radially outer side of the first groove and a radially outer side of the radially magnetized permanent magnet to a width of the radially magnetized permanent magnet is between 0.20 and 0.26.
8. 8. The electric machine rotor of claim 1, wherein a ratio of a width of the second groove to a width of the circumferentially-charged permanent magnet is between 0.16 and 0.19.
9. 9. The electric machine rotor of claim 1, wherein a ratio of a distance between a radially outer side of the second groove and a radially outer side of the circumferentially-charged permanent magnet to a width of the circumferentially-charged permanent magnet is between 0.25 and 0.31.
10. 10. A permanent magnet synchronous motor comprising a motor rotor according to any one of claims 1 to 9.

Description

Motor rotor and permanent magnet synchronous motor Technical Field The present utility model relates to a motor rotor and a permanent magnet synchronous motor, and more particularly, to a motor rotor having higher strength and a permanent magnet synchronous motor including the motor rotor. Background The permanent magnets of the motor rotor are fixed to the iron core so as to rotate under the action of the magnetic field to output torque and rotation speed outwards. However, for high-power permanent magnet synchronous motors, the fixation between the permanent magnet and the iron core may be unreliable, which easily causes the permanent magnet to crack or break away during operation of the motor, resulting in a safety hazard. For this reason, it is desirable to propose a motor rotor that ameliorates the above-described deficiencies in the prior art. Disclosure of utility model According to a first aspect of the utility model, a motor rotor is provided, which comprises a rotor core, at least two stages of permanent magnet assemblies arranged along the axial direction, wherein each permanent magnet assembly comprises a plurality of radial magnetizing permanent magnets which are arranged on the outer side of the circumference of the rotor core and generate a magnetic field in the approximately radial direction, a plurality of circumferential magnetizing permanent magnets which are arranged on the outer side of the circumference of the rotor core and generate a magnetic field in the approximately circumferential direction, the circumferential magnetizing permanent magnets and the radial magnetizing permanent magnets are alternately arranged in the circumferential direction, a first groove extending along the circumferential direction is formed in the axial end face of each radial magnetizing permanent magnet, a second groove extending along the circumferential direction is formed in the axial end face of each circumferential magnetizing permanent magnet, an injection molding body is filled in the rotor core and extends into the first groove and the second groove to fix the rotor core and the permanent magnet assemblies together, and the first groove and the second groove are at least partially staggered along the circumferential direction. According to this aspect, the injection molding filled in the first groove and the second groove can strengthen the fixing strength between the permanent magnet assembly and the rotor core. In addition, because the first groove and the second groove are at least partially staggered along the circumferential direction, the injection molding body forms a staggered gear-like structure at the adjacent position of the radial magnetizing permanent magnet and the circumferential magnetizing permanent magnet after the injection molding process is completed, and the gear-like structure can provide circumferential support for the permanent magnet assembly, so that the strength of the motor rotor is further improved. In some aspects, the first groove may be located outside the second groove in a radial direction. In some aspects, the first groove and the second groove may communicate in a circumferential direction. According to this scheme, because first recess and second recess are along circumference direction intercommunication, first recess and second recess can form the holding tank jointly, and the injection molding body is filled in the holding tank in order to fix rotor core and permanent magnet subassembly together, has further improved motor rotor's intensity. In some aspects, the radial-magnetization permanent magnet may have, in order from a radial inner side to a radial outer side, a first flat surface, a first concave portion recessed toward an axial inner side of the radial-magnetization permanent magnet with respect to the first flat surface, and a first protruding portion protruding toward an axial outer side of the radial-magnetization permanent magnet with respect to the first flat surface, the first concave portion forming a first groove. In some aspects, the circumferential magnetized permanent magnet may have a second flat surface, a second concave portion, and a second protruding portion in order from a radially inner side to a radially outer side, the second concave portion being recessed toward an axially inner side of the radial magnetized permanent magnet with respect to the second flat surface, the second protruding portion protruding toward an axially outer side of the radial magnetized permanent magnet with respect to the second flat surface, the second concave portion forming a second groove. In some aspects, the ratio of the width of the first groove to the width of the radially charged permanent magnet may be between 0.15 and 0.18. In some aspects, a ratio of a distance between a radially outer side of the first groove and a radially outer side of the radially magnetized permanent magnet to a width of the radially magnetized permanent magnet may be betwe