A segmented embedded motor rotor structure

Abstract

The utility model discloses a kind of segmented embedded motor rotor structure, belong to permanent magnet synchronous motor field, including several segments along axial sequentially arranged rotor core, at least two mounting slots that are evenly provided with on the outer wall of rotor core around axis and penetrate the both ends of rotor core;Iron core inlay is equipped in mounting slot, iron core inlay is detachably connected with rotor core by connecting piece, and there is gap between iron core inlay and mounting slot side wall;Wherein, first magnetic steel groove is formed between iron core inlay and the side wall of mounting slot, and first permanent magnet is equipped in first magnetic steel groove.The beneficial effects of the present application are as follows: the rotor core and the iron core inlay are connected by the connecting piece, the structure is simple, and the assembly is convenient;The original magnetic bridge is cancelled, which can ensure the strength of the rotor, reduce the magnetic flux leakage, increase the utilization rate of permanent magnet and reduce the cost.

Description

Technical Field

[0001] This utility model relates to the field of permanent magnet synchronous motors, specifically to a segmented embedded motor rotor structure. Background Technology

[0002] A permanent magnet synchronous motor consists of components such as a stator, a rotor, and end caps. The rotor is one of the core components of a permanent magnet synchronous motor, and its design and performance directly affect the efficiency of the motor. The rotor can be made in a solid form or it can be made by laminating and pressing laminations, and it is fitted with permanent magnet material.

[0003] In existing technologies, the design contradiction between rotor strength and magnetic bridge makes it impossible to significantly improve performance while reducing material usage: Since the magnetic bridge needs to balance mechanical strength and magnetic resistance performance, if it is too thin, it is prone to breakage, and the rotor structure will be damaged by centrifugal force, resulting in harmful deformation and even motor damage; if it is too thick, it will increase magnetic leakage and reduce the utilization rate of magnets, requiring more magnets to meet performance requirements, which will significantly increase material costs. Utility Model Content

[0004] In view of the above-mentioned shortcomings of the existing technology, the technical problem to be solved by this utility model is to provide a motor rotor structure that can eliminate the magnetic isolation bridge, ensure structural strength, and reduce magnetic leakage.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a segmented embedded motor rotor structure, comprising several rotor cores arranged sequentially along the axial direction, and at least two mounting slots penetrating both ends of the rotor core are evenly arranged on the outer wall of the rotor core around the axis; a core insert is provided in the mounting slot, the core insert is detachably connected to the rotor core through a connector, and there is a gap between the core insert and the side wall of the mounting slot; wherein, a first magnetic steel groove is formed between the core insert and the two side walls of the mounting slot, and a first permanent magnet is provided in each of the first magnetic steel grooves.

[0006] The beneficial effects of this solution are as follows: the rotor core and core inserts are connected by connectors, which makes the structure simple and easy to assemble; the original magnetic isolation bridge is eliminated, which can not only ensure the strength of the rotor and reduce magnetic leakage, but also increase the utilization rate of permanent magnets and reduce costs.

[0007] Preferably, the number of rotor cores is three to six, and the mounting slots on adjacent rotor cores are staggered in the circumferential direction.

[0008] The beneficial effects of adopting the above-mentioned preferred scheme are: by segmenting the skewed poles of the rotor core, the magnetic field distribution is changed to weaken spatial harmonics, which can significantly improve the overall performance of the motor, reduce noise, and improve NVH performance.

[0009] Preferably, the connector includes multiple rows of inserts and two single rows of inserts. At the bottom of the mounting groove and at the corresponding position of the core insert, there are slots corresponding to the multiple rows of inserts and the two single rows of inserts. The two ends of the single rows of inserts and the multiple rows of inserts are respectively inserted into the corresponding slots to realize the fitting connection between the rotor core and the core insert.

[0010] The advantages of adopting the above preferred scheme are: the interlocking connection is convenient to assemble; the multi-row inserts and single-row inserts are set separately to form a spatial frame structure, which improves the connection strength; and the connection space is reserved for the connecting magnetic bridge of the transition piece.

[0011] Preferably, both ends of the rotor core are provided with transition plates for connecting the rotor core and the core insert; the transition plates are provided with clearance grooves to avoid single-row inserts and multi-row inserts.

[0012] The advantages of adopting the above preferred solution are: the transition plate also serves to connect the rotor core and the core insert, improves the connection strength, and surrounds the multi-row inserts and the single-row inserts.

[0013] Preferably, the rotor core is provided with a plurality of first fastening points, the core insert is provided with a plurality of second fastening points, and the transition plate is provided with third fastening points that respectively cooperate with the first fastening points and the second fastening points.

[0014] The advantages of adopting the above preferred scheme are: the use of snap-fit ​​connection simplifies assembly and achieves a stable connection between the rotor core and the core insert.

[0015] Preferably, the ends of the single-row insert and the multi-row insert are lower than the end faces of the transition plates at both ends of the rotor core.

[0016] The advantages of adopting the above preferred scheme are: the ends of the single-row insert and the multi-row insert are lower than the end faces of the transition plates on both sides in the length direction, which reduces the assembly accuracy and processing difficulty of the ends of the single-row insert and the multi-row insert, and facilitates the splicing of multiple rotor core segments and the segmented skew poles.

[0017] Preferably, the outer side of the iron core insert is provided with two second magnet slots, the two ends of the two second magnet slots penetrate the iron core insert and the inner sides are close to each other, and a second permanent magnet is provided in each of the two second magnet slots.

[0018] The advantages of adopting the above-mentioned preferred scheme are: it increases the number of permanent magnets, eliminates the original magnetic isolation bridge, and has a stronger permanent magnet utilization rate and magnetic field strength. Attached Figure Description

[0019] Appendix Figure 1 This is a schematic diagram of the overall design of this utility model; Appendix Figure 2This is a three-dimensional schematic diagram of the rotor core and core insert of this utility model; Appendix Figure 3 This is a planar schematic diagram of the rotor core and core insert of this utility model; Appendix Figure 4 This is a schematic diagram of the transition piece of this utility model.

[0020] Explanation of reference numerals in the attached drawings: 1. Rotor core; 2. Core insert; 3. Connector; 4. First magnet slot; 5. First permanent magnet; 6. Transition plate; 7. Clearance slot; 8. First fastening point; 9. Second fastening point; 10. Third fastening point; 11. Second magnet slot; 12. Second permanent magnet; 13. Connecting magnetic bridge; 301. Multi-row insert; 302. Single-row insert. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely represents selected embodiments of the utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0022] Example 1 like Figures 1 to 3 As shown, a segmented embedded motor rotor structure includes several rotor cores 1 arranged sequentially along the axial direction. At least two mounting slots penetrating both ends of the rotor core 1 are evenly arranged on the outer wall of the rotor core 1 around the axis. Core inserts 2 are provided in the mounting slots. The core inserts 2 are detachably connected to the rotor core 1 through connectors 3, and there is a gap between the core inserts 2 and the side walls of the mounting slots. A first magnetic groove 4 is formed between the core inserts 2 and the side walls of the mounting slots. A first permanent magnet 5 is provided in each of the first magnetic grooves 4.

[0023] like Figures 1 to 3 As shown, two second magnet slots 11 are provided on the outer side of the iron core insert 2. The two ends of the two second magnet slots 11 penetrate the iron core insert 2 and their inner sides are close to each other. A second permanent magnet 12 is provided in each of the two second magnet slots 11.

[0024] A conventional permanent magnet synchronous motor includes a stator and a rotor. The stator is cylindrical, and several coil windings are evenly arranged inside the stator. The rotor is located inside the stator and is made of stacked silicon steel sheets. Multiple permanent magnets are evenly embedded on the rotor. By energizing the coil windings of the stator, a magnetic field is generated, thereby driving the rotor to rotate.

[0025] The structure inside the rotor used to isolate two adjacent permanent magnets is called a magnetic isolation bridge. The cross-sectional area of ​​the magnetic isolation bridge determines the magnitude of the magnetic reluctance. The narrower the magnetic isolation bridge, the greater the magnetic reluctance, but the lower the mechanical strength, and the more easily it is damaged during high-speed rotation. The thicker the magnetic isolation bridge, the higher the mechanical strength, but the lower the magnetic reluctance, and the more prone it is to magnetic leakage. Since the characteristics of magnetic flux are similar to those of electric current, it will preferentially choose the path with the least magnetic reluctance to flow. After the magnetic reluctance of the magnetic isolation bridge is reduced, more of the main magnetic flux that should have entered the stator through the air gap will pass through the magnetic isolation bridge, causing magnetic leakage. The more magnetic leakage, the more the magnetic flux is not participating in the energy conversion of the motor, and the lower the motor efficiency.

[0026] In this embodiment, the mounting slot of the rotor core 1 is a wedge-shaped structure that is narrow inside and wide outside. The number of mounting slots is generally six to eight, with a minimum of two. Each mounting slot has a core insert 2 installed in it. The outer wall of the core insert 2 and the wall of the mounting slot are joined together to form the first magnet slot 4. Several protrusions are also provided on the inner wall of one side of the mounting slot to hold the first permanent magnet 5 in place and prevent it from swaying left and right.

[0027] This solution eliminates the magnetic isolation bridge, completely separates the rotor core 1 and the core insert 2, and then reconnects them through the connector 3. This not only ensures rotor strength and reduces magnetic leakage, but also increases the utilization rate of permanent magnets and reduces costs.

[0028] In addition, two second magnet slots 11 are provided on the outer side of the iron core insert 2, and a second permanent magnet 12 is provided in each of the two second magnet slots 11. This increases the number of permanent magnets and eliminates the original magnetic isolation bridge, resulting in a higher utilization rate of permanent magnets and a stronger magnetic field.

[0029] Example 2 like Figure 1 As shown, based on Embodiment 1, the number of rotor cores 1 is three to six, and the mounting slots on two adjacent rotor cores 1 are staggered in the circumferential direction.

[0030] In this embodiment, multiple rotor core segments 1 are sequentially staggered, and the first permanent magnet 5 on each rotor core segment 1 rotates axially at a certain angle, causing a change in the interaction between the rotor magnetic field and the stator magnetic field. This tilt can be continuous, such as a spiral-shaped skewed pole, or segmented, such as segmented staggered pole.

[0031] Each rotor core segment 1 is not connected to the others; they are all sleeved on the motor shaft and fixed by the motor shaft. Each rotor core segment 1 is staggered.

[0032] Example 3 like Figures 1 to 2 As shown, based on embodiments 1 and 2, the connector 3 includes multiple rows of inserts 301 and two single rows of inserts 302. At the bottom of the mounting groove and at the corresponding position of the core insert 2, there are slots corresponding to the multiple rows of inserts 301 and the two single rows of inserts 302. The two ends of the single row of inserts 302 and the multiple rows of inserts 301 are respectively inserted into the corresponding slots to realize the fitting connection between the rotor core 1 and the core insert 2.

[0033] In this embodiment, both the single-row insert 302 and the multi-row insert 301 are made of materials with high strength but low magnetic permeability, such as 7-series aluminum alloys, austenitic stainless steel, etc.

[0034] The single-row insert 302 and the multi-row insert 301 are used to connect the rotor core 1 and the core insert 2. The reason for the separate design is to reserve connection space for the connecting magnetic bridge 13 of the transition plate 6, and to avoid the transition plate 6 from splitting into several pieces.

[0035] like Figure 1 , Figure 2 and Figure 4 As shown, both ends of the rotor core 1 are provided with transition plates 6 for connecting the rotor core 1 and the core insert 2; the transition plates 6 are provided with clearance grooves 7 for avoiding single-row inserts 302 and multi-row inserts 301.

[0036] like Figures 1 to 4 As shown, the rotor core 1 is provided with a plurality of first fastening points 8, the core insert 2 is provided with a plurality of second fastening points 9, and the transition plate 6 is provided with third fastening points 10 that respectively cooperate with the first fastening points 8 and the second fastening points 9.

[0037] like Figure 1 As shown, the ends of the single-row insert 302 and the multi-row insert 301 are lower than the end faces of the transition plates 6 at both ends of the rotor core 1.

[0038] In this embodiment, each rotor core 1 is made of multiple stacked silicon steel sheets, both ends of which are covered with insulating material, and the sheets are mechanically connected to each other via snap-fit ​​points. The transition sheet 6 is made of the same material as the rotor core 1, which is also a silicon steel sheet covered with insulating material. The transition sheets 6 at both ends are mechanically connected to the end faces of the rotor core 1 via the first snap-fit ​​point 8, the second snap-fit ​​point 9, and the third snap-fit ​​point 10, which strengthens the connection between the rotor core 1 and the core insert 2, forming a complete rotor core 1, which can achieve higher integrity and adapt to speeds above 20,000 rpm.

[0039] (In the prior art, snap-fit ​​connection involves punching out protruding snap-fit ​​points on silicon steel sheets. The friction between these snap-fit ​​points and the next layer of silicon steel sheets allows multiple layers of silicon steel sheets to be tightly bonded together. Other connection methods alongside snap-fit ​​connection include adhesive bonding and fusion welding.) The transition plate 6 has a clearance groove 7 to avoid the single-row insert 302 and the multi-row insert 301. Therefore, the single-row insert 302 and the multi-row insert 301 need to be designed separately, leaving two connecting magnetic bridges 13 to prevent the transition plate 6 part located on the rotor core 1 and the transition plate 6 part located on the core insert 2 from breaking.

[0040] In addition, when multiple rotor core segments 1 are assembled sequentially along the axial direction, the single-row insert 302, the multi-row insert 301 and the rotor core 1 all have tolerances, making it difficult to ensure that the single-row insert 302 and the multi-row insert 301 can hold the rotor core 1 and the core insert 2 while not protruding from the two end faces of the rotor core 1. If they protrude, the multiple rotor core segments 1 cannot be properly assembled and tilted.

[0041] In this design, the transition plates 6 cover both ends of the rotor core 1 and provide clearance grooves 7, enclosing the multi-row inserts 301 and the single-row inserts 302. Even if the ends of the single-row inserts 302 and the multi-row inserts 301 protrude from the end face of the rotor core 1 due to errors, they will still be lower than the end faces of the transition plates 6 on both sides. When the multiple rotor core segments 1 are assembled together, they are abutted against each other by the transition plates 6, thereby reducing the assembly accuracy and processing difficulty at both ends of the single-row inserts 302 and the multi-row inserts 301, facilitating the assembly of the multiple rotor core segments 1 and the segmented skew poles.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and not to limit the technical solutions. Those skilled in the art should understand that any modifications or equivalent substitutions to the technical solutions of this utility model that do not depart from the spirit and scope of this technical solution should be covered within the scope of the claims of this utility model.

Claims

1. A segmented embedded motor rotor structure, characterized in that, The rotor core (1) consists of several sections arranged sequentially along the axial direction. At least two mounting slots are uniformly arranged around the axis on the outer wall of the rotor core (1) and pass through both ends of the rotor core (1). A core insert (2) is provided in the mounting slot. The core insert (2) is detachably connected to the rotor core (1) through a connector (3). There is a gap between the core insert (2) and the side wall of the mounting slot. A first magnetic steel groove (4) is formed between the core insert (2) and the two side walls of the mounting slot. A first permanent magnet (5) is provided in the first magnetic steel groove (4).

2. The segmented embedded motor rotor structure according to claim 1, characterized in that, The number of rotor cores (1) is three to six, and the mounting slots on two adjacent rotor cores (1) are staggered in the circumferential direction.

3. The segmented embedded motor rotor structure according to claim 1, characterized in that, The connector (3) includes multiple rows of inserts (301) and two single rows of inserts (302). At the bottom of the mounting groove and at the corresponding position of the core insert (2), there are slots corresponding to the multiple rows of inserts (301) and the two single rows of inserts (302). The two ends of the single rows of inserts (302) and the multiple rows of inserts (301) are respectively inserted into the corresponding slots to realize the fitting connection between the rotor core (1) and the core insert (2).

4. The segmented embedded motor rotor structure according to claim 3, characterized in that, Both ends of the rotor core (1) are provided with transition plates (6) for connecting the rotor core (1) and the core insert (2); the transition plates (6) are provided with clearance grooves (7) for avoiding single-row inserts (302) and multi-row inserts (301).

5. A segmented embedded motor rotor structure according to claim 4, characterized in that, The rotor core (1) is provided with a number of first fastening points (8), the core insert (2) is provided with a number of second fastening points (9), and the transition plate (6) is provided with third fastening points (10) that cooperate with the first fastening points (8) and the second fastening points (9) respectively.

6. The segmented embedded motor rotor structure according to claim 4, characterized in that, The ends of the single-row insert (302) and the multi-row insert (301) are lower than the end faces of the transition plates (6) at both ends of the rotor core (1).

7. A segmented embedded motor rotor structure according to any one of claims 1 to 6, characterized in that, The outer side of the iron core insert (2) is provided with two second magnet slots (11), the two ends of the two second magnet slots (11) penetrate the iron core insert (2) and the inner sides are close to each other. A second permanent magnet (12) is provided in each of the two second magnet slots (11).

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