Rotor and permanent magnet synchronous motor

Abstract

The present invention relates to a rotor and a permanent magnet synchronous motor, comprising a rotor core, wherein an even number of magnetic steel slots for installing main permanent magnets are provided on the end surface of the rotor core in the axial direction, and the even number of magnetic steel slots are arranged at intervals along the circumferential direction of the rotor core; the end surface of the rotor core in the axial direction is also provided with a magnetizing slot for installing a guide permanent magnet; wherein a magnetizing slot is arranged at intervals between each two adjacent magnetic steel slots, and the guide permanent magnet installed in the magnetizing slot guides the magnetic force line of one of the main permanent magnets installed in each two adjacent main magnetic steel slots to the other, and the closed magnetic force line formed between each two adjacent main permanent magnets passes through the stator. The guide permanent magnet located between each two adjacent main permanent magnets guides the direction of the main magnetic flux, so that the original leakage magnetic flux is added to the main magnetic flux to form an effective main magnetic field, so that the electromagnetic torque of the permanent magnet synchronous motor is increased due to the enhancement of the main magnetic field, thereby greatly improving the working efficiency of the permanent magnet synchronous motor.

Description

Technical Field

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

[0002] The permanent magnet synchronous motor mainly includes a stator and a rotor. The rotor includes a rotor core and a permanent magnet. The permanent magnet is installed in the magnetic steel slot of the rotor core. When a three-phase symmetrical current is passed through the stator side, since the three-phase stator is 120° apart in spatial position, the three-phase stator current generates a rotating magnetic field in space. The rotor moves under the action of electromagnetic force in the rotating magnetic field, and the electrical energy is converted into kinetic energy. When the permanent magnet generates a rotating magnetic field, the three-phase stator winding induces a three-phase symmetrical current through armature reaction under the action of the rotating magnetic field, and the rotor kinetic energy is converted into electrical energy.

[0003] Currently, the industry requires permanent magnet synchronous motors to have higher working efficiency. In order to improve the working efficiency of permanent magnet synchronous motors, various manufacturers have adopted top-notch materials. This has greatly increased the manufacturing cost of the motor while improving the efficiency. Summary of the invention

[0004] Based on this, it is necessary to provide a rotor and a permanent magnet synchronous motor that can improve the working efficiency of the permanent magnet synchronous motor and reduce the cost in order to solve the problem that the cost increases significantly due to improving the working efficiency of the permanent magnet synchronous motor.

[0005] A rotor comprises a rotor core, wherein an axial end surface of the rotor core is provided with an even number of magnetic steel slots for mounting main permanent magnets, and the even number of magnetic steel slots are arranged at intervals along the circumferential direction of the rotor core;

[0006] The axial end surface of the rotor core is also provided with a magnetic guide groove for installing a guide permanent magnet;

[0007] Among them, the magnetic attraction groove is arranged between each two adjacent magnetic steel grooves, and the guide permanent magnet installed in the magnetic attraction groove guides the magnetic lines of force of one of the main permanent magnets installed in each two adjacent magnetic steel grooves to the other, and the closed magnetic lines of force formed between each two adjacent main permanent magnets pass through the stator.

[0008] In one embodiment, the inner end points of each two adjacent magnetic steel grooves that are close to each other are connected to form a first connecting straight line, and the outer end points of each two adjacent magnetic steel grooves that are close to each other are connected to form a second connecting straight line, and the area of ​​the magnetic induction groove located within the first connecting straight line is greater than the area of ​​the part located outside the second connecting straight line.

[0009] In one embodiment, all of the magnetic induction grooves are located on a side of the first connecting straight line close to the central axis of the rotor core.

[0010] In one of the embodiments, the shapes of the two ends of each magnetic induction groove respectively match the inner contour shapes of the two adjacent magnetic steel grooves.

[0011] In one embodiment, the perpendicular bisector of the first connecting straight line passes through the center of the magnetic induction groove.

[0012] In one of the embodiments, the magnetic induction slot is in the shape of an arc that is bent away from the central axis of the rotor core.

[0013] In one of the embodiments, at least two magnetic induction grooves are spaced apart on one side of the central axis of the rotor core between each two adjacent magnetic steel grooves.

[0014] In one of the embodiments, the at least two magnetic induction grooves are arranged in parallel.

[0015] In one of the embodiments, the rotor further includes a main permanent magnet and a guide permanent magnet, the main permanent magnet is installed in the magnetic steel slot, and the guide permanent magnet is installed in the magnetic guide slot.

[0016] A permanent magnet synchronous motor comprises a stator and a rotor as described in any one of the above items, wherein the rotor is rotatably sleeved in the stator.

[0017] In the rotor and permanent magnet synchronous motor provided by the present invention, the guide permanent magnet located between each two adjacent main permanent magnets guides the direction of the main magnetic flux, so that the original leakage magnetic flux (when the guide permanent magnet is not provided, there will be leakage magnetic flux at the end of the single-piece main permanent magnet) is added to the main magnetic flux to form an effective main magnetic field. In this way, due to the enhancement of the main magnetic field, the electromagnetic torque of the permanent magnet synchronous motor is increased, thereby greatly improving the working efficiency of the permanent magnet synchronous motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 An axonometric diagram of a permanent magnet synchronous motor provided in one embodiment of the present invention;

[0019] Figure 2 for Figure 1 A front view of a permanent magnet synchronous motor provided in;

[0020] Figure 3 for Figure 2 The enlarged view of point A of the permanent magnet synchronous motor provided in;

[0021] Figure 4 for Figure 2 The magnetic field line trend diagram of the permanent magnet synchronous motor provided in;

[0022] Figure 5 for Figure 4The enlarged view of point B of the permanent magnet synchronous motor provided in;

[0023] Figure 6 A front view of a permanent magnet synchronous motor provided according to another embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0025] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0027] See also Figure 1-Figure 3 An embodiment of the present invention provides a permanent magnet synchronous motor 100, including a stator 10 and a rotor, wherein the rotor is coaxially sleeved in the stator 10, and an air gap is provided between the rotor and the stator 10 to facilitate the rotor to rotate relative to the stator 10.

[0028] A plurality of teeth 11 are arranged at intervals along the circumferential direction in the stator 10 . A stator coil is wound around each tooth 11 . When the stator coil is energized, a rotating magnetic field is generated, which acts on the rotor to cause the rotor to rotate.

[0029] The rotor includes a rotor core 21 and a permanent magnet, and the permanent magnet is axially installed in the rotor core 21. Specifically, an even number of magnetic steel slots 211 are provided on the axial end surface of the rotor core 21, and the even number of magnetic steel slots 211 are arranged at intervals along the circumferential direction of the rotor core 21. Specifically, the even number of magnetic steel slots 211 are evenly spaced along the circumferential direction of the rotor core 21, and the magnetic steel slots 211 are through slots opened along the axial direction of the rotor core 21.

[0030] The axial end surface of the rotor core 21 is also provided with a magnetizing groove 212, which is disposed between every two adjacent magnetic steel grooves 211. In this specific embodiment, the magnetizing groove 212 is a through groove provided along the axial direction of the rotor core 21.

[0031] The permanent magnets include main permanent magnets 221 and guide permanent magnets 222. Each main permanent magnet 221 is installed in each magnetic steel slot 211 (the shape of the main permanent magnet 221 matches the shape of the magnetic steel slot 211), and each guide permanent magnet 222 is installed in each magnetizing slot 212 (the shape of the guide permanent magnet 222 matches the shape of the magnetizing slot 212). The interaction between each two adjacent main permanent magnets 221 generates closed magnetic lines of force, and the closed magnetic lines of force pass through the stator coil so that the magnetic field formed by the main permanent magnets 221 acts on the stator coil. At this time, the magnetic flux formed by the magnetic flux between each two adjacent main permanent magnets 221 is defined as the main magnetic flux. The guide permanent magnet 222 is installed in the magnetizing slot 212 to guide the direction of the magnetic field between each two adjacent main permanent magnets 221.

[0032] See also Figure 4 and Figure 5 Since a magnetic induction groove 212 is provided between every two adjacent magnetic steel grooves 211, the guide permanent magnet 222 installed in the magnetic induction groove 212 will guide the magnetic lines of force of one of the main permanent magnets 221 installed in every two adjacent main magnetic steel grooves 211 to the other, that is, the guide permanent magnet 222 located between every two adjacent main permanent magnets 221 guides the direction of the main magnetic flux, so that the original leakage magnetic flux (when the guide permanent magnet 222 is not provided, there will be leakage magnetic flux at the end of the single-piece main permanent magnet 221) is added to the main magnetic flux to form an effective main magnetic field. In this way, due to the enhancement of the main magnetic field, the electromagnetic torque of the permanent magnet synchronous motor 100 is increased, thereby greatly improving the working efficiency of the permanent magnet synchronous motor 100.

[0033] Specifically, the direction of the magnetic field lines of the guide permanent magnet 222 is related to the direction of the main magnetic flux formed by the two adjacent main permanent magnets 221. Figure 5 As shown in the middle direction, the right end of the main permanent magnet 221 arranged in the up-down direction is an N pole, and the left end is an S pole, and the upper end of the main permanent magnet 221 arranged in the left-right direction is an N pole, and the lower end is an S pole. At this time, the direction of the main magnetic flux flows from the N pole of the main permanent magnet 221 arranged in the up-down direction to the S pole of the main permanent magnet 221 arranged in the left-right direction, and flows from the N pole of the main permanent magnet 221 arranged in the left-right direction to the S pole of the main permanent magnet 221 arranged in the up-down direction. At this time, the end of the guide permanent magnet 222 close to the main permanent magnet 221 arranged in the up-down direction is an S pole, and correspondingly, the end of the main permanent magnet 221 close to the left-right direction is an N pole.

[0034] In another embodiment, when the right end of the main permanent magnet 221 set in the up-down direction is an S pole and the left end is an N pole, and the upper end of the main permanent magnet 221 set in the left-right direction is an S pole and the lower end is an N pole, at this time, the direction of the main magnetic flux flows from the N pole of the main permanent magnet 221 set in the left-right direction to the S pole of the main permanent magnet 221 set in the up-down direction, and from the N pole of the main permanent magnet 221 set in the up-down direction to the S pole of the main permanent magnet 221 set in the left-right direction, then at this time, the end of the guide permanent magnet 222 close to the main permanent magnet 221 set in the up-down direction is set as the N pole, and correspondingly, the end of the main permanent magnet 221 close to the left-right direction is the S pole.

[0035] In one embodiment, the cross-sectional shape of the magnetic steel slot 211 is a rectangle. It is understandable that in other embodiments, the cross-sectional shape of the magnetic steel slot 211 can also be set to be an arc shape. The setting of the cross-sectional shape of the magnetic steel slot 211 is related to the specific structure of the rotor and is not limited here.

[0036] In one embodiment, the inner end points of each two adjacent magnetic steel grooves 211 that are close to each other are connected to each other to form a first connecting straight line a, and the outer end points of each two adjacent magnetic steel grooves 211 that are close to each other are connected to each other to form a second connecting straight line b, and the area of ​​the portion of the magnetic induction groove 212 located within the first connecting straight line a is greater than the area located outside the second connecting straight line b. When the guiding permanent magnet 222 is located outside the second connecting straight line b, a closed magnetic field is formed between the guiding permanent magnet 222 and the two adjacent main permanent magnets 221, and the magnetic lines of force of the magnetic field will not be able to pass through the stator coil. At this time, the guiding permanent magnet 222 will increase the leakage magnetic field of the main permanent magnet 221. When the guiding permanent magnet 222 is located within the first connecting straight line a, the guiding permanent magnet 222 can guide the direction of the main magnetic flux of the two adjacent main permanent magnets 221. At this time, the guiding permanent magnet 222 will reduce the leakage magnetic field of the main permanent magnet 221. When the area of ​​the part of the guiding permanent magnet 222 located within the first connecting straight line a is larger than the area located outside the second connecting straight line b, the leakage magnetic field of the main permanent magnet 221 can be reduced.

[0037] Specifically, the inner end points of the mutually adjacent ends of each two adjacent magnetic steel slots 211 are connected to form a connecting straight line a, and the magnetic guide slot 212 is located on the side of the connecting straight line a close to the central axis of the rotor core 21. In this way, it is ensured that each part of the guide permanent magnet 222 can reduce the leakage magnetic flux of the main permanent magnet 221, and the number of leakage magnetic flux added to the main magnetic flux is increased to form a more effective main magnetic field.

[0038] It can be understood that in other embodiments, part of the magnetic steel slots 211 can be arranged on the side of the connecting straight line a away from the central axis of the rotor core 21, as long as the area of ​​the magnetic induction slots 212 located within the first connecting straight line a is larger than the area outside the second connecting straight line b, and no limitation is made here.

[0039] In one embodiment, at least two magnetic induction slots 212 are spaced apart on one side close to the central axis of the rotor core 21 between each two adjacent magnetic field slots, and the guide permanent magnets 222 in the two magnetic induction slots 212 jointly add the leakage magnetic flux of the original single-piece main permanent magnet 221 to the main magnetic flux to form an effective main magnetic field, thereby further increasing the number of leakage magnetic flux added to the main magnetic flux.

[0040] In one embodiment, the shapes of the two ends of each magnetic guide slot 212 are respectively matched with the inner contour shapes of the two adjacent magnetic steel slots 211. This ensures that the direction of the magnetic force lines of the guide permanent magnet 222 is highly consistent with the direction of the main magnetic flux, further increasing the amount of leakage flux added to the main magnetic flux.

[0041] Specifically, the perpendicular midline c connecting the straight lines a passes through the center of the magnetic induction groove 212, so that the cross-sectional areas of the magnetic induction grooves 212 on both sides of the perpendicular midline c are equal.

[0042] Specifically, the magnetic induction groove 212 is an arc-shaped shape bent away from the central axis of the rotor core 21, ensuring that the direction of the magnetic field inside the guide permanent magnet 222 installed in the magnetic induction groove 212 is along the circumferential direction of the guide permanent magnet 222, ensuring that the direction of the magnetic field in the guide permanent magnet 222 is consistent with the direction of the magnetic field of each adjacent two main permanent magnets 221, thereby further reducing the leakage magnetic phenomenon at the end of the single-piece main permanent magnet 221.

[0043] In another embodiment, the magnetizing groove 212 may be arranged not to be an arc shape bent away from the central axis of the rotor core 21, for example, the magnetizing groove 212 may be in a rectangular shape, and the shapes of the two ends of the rectangle respectively match the inner contour shapes of the two adjacent magnetic steel grooves 211. However, at this time, it can still be ensured that the guide permanent magnet 222 installed in the magnetizing groove 212 can guide the direction of the main magnetic flux, so as to reduce the magnetic leakage phenomenon at the end of the single-piece main permanent magnet 221.

[0044] See also Figure 6 In one embodiment, two magnetizing slots 212 are arranged between each two adjacent magnetic field slots on one side close to the central axis of the rotor core 21, and the two magnetizing slots 212 are arranged in parallel. Specifically, the area of ​​a magnetizing slot 212 close to the central axis of the rotor core 21 is larger than the area of ​​a magnetizing slot 212 far from the central axis of the rotor core.

[0045] It can be understood that in another embodiment, three magnetizing slots 212, four magnetizing slots 212 or more than four magnetizing slots 212 may be provided on one side of the central axis of the rotor core 21 between each two adjacent magnetic field slots, which is not limited here. And when at least two magnetizing slots 212 are provided at intervals on one side of the central axis of the rotor core 21 between each two adjacent magnetic field slots, at least two magnetizing slots 212 may also have a certain angle between them, that is, at least two magnetizing slots 212 are non-parallel, which is not limited here either.

[0046] In one embodiment, the rotor core 21 is further provided with a plurality of through holes 213 along the axial direction, and the plurality of through holes 213 are spaced apart and located on one side of the magnetic steel slot 211 close to the central axis of the rotor core 21. The provision of the through holes 213 facilitates gas circulation and can promote heat dissipation of the rotor core 21.

[0047] In another embodiment, the rotor core 21 is further provided with a magnetic flux sorting groove 214 along the axial direction, and each magnetic steel slot 211 is provided with a magnetic flux sorting groove 214 on one side away from the central axis of the rotor core 21 to effectively guide the direction of the main magnetic flux.

[0048] In one embodiment, the rotor core 21 is further provided with a magnetic isolation bridge 214 along the axial direction, and each magnetic steel slot 211 is provided with a magnetic isolation bridge 215 at both ends along the circumferential direction.

[0049] An embodiment of the present invention further provides a rotor included in the permanent magnet synchronous motor 100 .

[0050] In the rotor and permanent magnet synchronous motor 100 provided by the embodiment of the present invention, the guide permanent magnet 222 located between each two adjacent main permanent magnets 221 guides the direction of the main magnetic flux, so that the original leakage magnetic flux is added to the main magnetic flux to form an effective main magnetic field. In this way, due to the enhancement of the main magnetic field, the electromagnetic torque of the permanent magnet synchronous motor 100 is increased, thereby greatly improving the working efficiency of the permanent magnet synchronous motor 100; at the same time, since the magnetic flux guiding groove 212 is an arc shape bent away from the central axis of the rotor core 21, it is ensured that the magnetic field direction inside the guide permanent magnet 222 installed in the magnetic flux guiding groove 212 is along the circumferential direction of the guide permanent magnet 222, and it is ensured that the magnetic field direction in the guide permanent magnet 222 is the same as the magnetic field direction of each two adjacent main permanent magnets 221, thereby further reducing the leakage magnetic phenomenon at the end of the single-piece main permanent magnet 221.

[0051] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0052] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A rotor (20), characterized in that: It comprises a rotor core (21), wherein an axial end surface of the rotor core (21) is provided with an even number of magnetic steel slots (211) for installing main permanent magnets (221), and the even number of magnetic steel slots (211) are arranged at intervals along the circumferential direction of the rotor core (21); The axial end surface of the rotor core (21) is also provided with a magnetic guide groove (212) for installing a guide permanent magnet (222); The magnetic attraction groove (212) is arranged between each two adjacent magnetic steel grooves (211), and the guide permanent magnet (222) installed in the magnetic attraction groove (212) guides the magnetic force line of one of the main permanent magnets (221) installed in each two adjacent magnetic steel grooves (211) to the other, and the closed magnetic force line formed between each two adjacent main permanent magnets (221) passes through the stator; The inner end points of the mutually adjacent ends of each two adjacent magnetic steel slots (211) are connected to each other to form a first connecting straight line (a); the magnetic induction slots (212) are all located on one side of the first connecting straight line (a) close to the central axis of the rotor core (21).

2. The rotor (20) according to claim 1, characterized in that The shapes of the two ends of each magnetic attraction groove (212) respectively match the inner contour shapes of the two adjacent magnetic steel grooves (211).

3. The rotor (20) according to claim 1, characterized in that The perpendicular bisector (c) of the first connecting straight line (a) passes through the center of the magnetic induction groove (212).

4. The rotor (20) according to any one of claims 1 to 3, characterized in that: The magnetic induction groove (212) is in the shape of an arc that is bent away from the central axis of the rotor core (21).

5. The rotor (20) according to claim 1, characterized in that At least two magnetic induction grooves (212) are arranged at intervals on one side close to the central axis of the rotor core (21) between each two adjacent magnetic steel grooves (211).

6. The rotor (20) according to claim 5, characterized in that The at least two magnetic induction grooves (212) are arranged in parallel.

7. The rotor (20) according to claim 1, characterized in that The rotor (20) further comprises a main permanent magnet (221) and a guide permanent magnet (222); the main permanent magnet (221) is installed in the magnetic steel slot (211), and the guide permanent magnet (222) is installed in the magnetic induction slot (212).

8. The rotor (20) according to claim 1, characterized in that The rotor core (21) is also provided with a plurality of flow holes (213) along the axial direction, and the plurality of flow holes (213) are spaced apart and located on one side of the magnetic steel slot (211) close to the central axis of the rotor core (21).

9. The rotor (20) according to claim 1, characterized in that The rotor core (21) is also provided with a magnetic flux sorting groove (214) along the axial direction, and each magnetic steel slot (211) is provided with the magnetic flux sorting groove (214) on a side away from the central axis of the rotor core (21).

10. A permanent magnet synchronous motor (100), characterized in that: It comprises a stator and a rotor (20) as claimed in any one of claims 1 to 9, wherein the rotor (20) is rotatably sleeved in the stator.

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