A rotor yoke separation type axial magnetic field permanent magnet synchronous motor

Abstract

The present invention discloses a rotor yoke separated axial magnetic field permanent magnet synchronous motor, comprising a stator, a rotor and a stationary rotor yoke. The stator and the stationary rotor yoke are wound from silicon steel sheets and are respectively located on both sides of the rotor. The stator comprises a stator core and a plurality of stator windings, and the rotor comprises a rotor core and a plurality of magnetic steels, and is yokeless or has a yoke only on one side close to the stationary rotor yoke. The motor proposed in the present invention only needs to appropriately adjust the thickness of the rotor yoke and the stationary rotor yoke so that the rotor moment of inertia can meet the requirements of different application scenarios, and is particularly suitable for occasions where there are strict requirements on the time constant in servo control, which greatly reduces the difficulty of configuring the moment of inertia. In addition, the present invention has a simple structure and is easy to process and install.

Description

Technical Field

[0001] The invention belongs to the field of magnetic field permanent magnet motors, and in particular relates to a rotor yoke separated axial magnetic field permanent magnet synchronous motor. Background Art

[0002] Axial magnetic field permanent magnet motors are widely used in electric vehicles, industrial production, aerospace and other fields due to their high torque density and compact space. There are three types of axial magnetic field permanent magnet motors: dual stator single rotor, dual rotor single stator and single stator single rotor. Among them, the conventional dual stator single rotor axial magnetic field motor has a smaller moment of inertia because its rotor has no yoke, so the dynamic performance is better. However, for some applications, too small moment of inertia will cause speed fluctuations, and if dual stator single rotor and single stator single rotor axial magnetic field motors are used, their rotor moment of inertia is too large and cannot meet the dynamic performance requirements. Therefore, it is necessary to configure the rotor moment of inertia of the dual stator single rotor axial magnetic field motor. On the other hand, due to the structural characteristics of the rotor of the conventional dual stator single rotor axial magnetic field motor, its rotor moment of inertia configuration is relatively complicated. Summary of the invention

[0003] The purpose of the present invention is to propose a rotor yoke separated axial magnetic field permanent magnet synchronous motor, which makes it easier to configure the rotor rotational inertia in the motor design and reduces the design difficulty.

[0004] The technical solution to achieve the purpose of the present invention is: a rotor yoke separation type axial magnetic field permanent magnet synchronous motor, including a stationary rotor yoke, a stator and a rotor, the rotor is arranged on the motor shaft, the rotor is located between the stationary rotor yoke and the stator, and an air gap is provided between the stationary rotor yoke and the stator, the rotor includes a plurality of magnetic steels and a rotor core, the magnetic steels are attached to the surface of the rotor core at equal intervals or embedded in the rotor core. Preferably, the magnetization direction of the magnetic steel is axially alternating positive and negative.

[0005] Preferably, the cross section of the magnetic steel is fan-shaped.

[0006] Preferably, the stationary rotor yoke is a disc structure formed by winding silicon steel sheets.

[0007] Preferably, the stator comprises a stator core and a plurality of stator windings, and the plurality of stator windings are embedded in stator slots of the stator core.

[0008] Preferably, the rotor core comprises two circular rings, which are connected by rotor spokes.

[0009] Preferably, the rotor has no yoke, and a plurality of magnets are embedded in the spokes of the rotor core, and the thickness of the magnets is equal to the thickness of the spokes.

[0010] Preferably, the rotor has a yoke, which is arranged between two circular rings, and the magnet is embedded between the spokes of the rotor core, with the bottom surface of the magnet fitting against the rotor yoke and the other surface flush with the end surface of the rotor core.

[0011] Preferably, when the thickness of the rotor yoke is greater than a set threshold, no spokes are required, and the magnetic steel is attached to the yoke of the rotor core.

[0012] Preferably, different rotor moment of inertia requirements are met by adjusting the thickness of the stationary rotor yoke or the thickness of the rotor yoke portion or the thickness of the stationary rotor yoke and the rotor yoke portion.

[0013] Compared with the prior art, the present invention has the following significant advantages: the present invention can meet the requirements of rotor rotational inertia in different application scenarios by flexibly adjusting the thickness of the stationary rotor yoke and the rotor yoke part, especially in servo control scenarios with requirements on time constants. This structure significantly simplifies the design process and reduces the design difficulty. In addition, the stationary rotor yoke has a simple structure and is easy to process and install. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural diagram of the rotor yoke separation type axial magnetic field permanent magnet synchronous motor of the present invention.

[0015] Figure 2 It is a schematic diagram of the rotor yoke-free form of the yoke-separated axial magnetic field motor of the present invention.

[0016] Figure 3 It is a schematic diagram of the rotor yoke form of the yoke separation type axial magnetic field motor of the present invention. Implementation

[0017] The present invention will be further described below in conjunction with the accompanying drawings.

[0018] like Figure 1The structure schematic diagram of the rotor yoke separation type axial magnetic field permanent magnet synchronous motor of the present invention is shown, comprising a stationary rotor yoke (1), a stator (2) and a rotor (3), wherein the rotor (3) is arranged on the motor shaft, and the rotor (3) is located between the stationary rotor yoke (1) and the stator (2), and an air gap (4) is arranged between the rotor (3) and the stationary rotor yoke (1) and the stator (2), and the rotor (3) comprises a plurality of magnetic steels (31) and a rotor core (32), and the magnetic steels (31) are attached to the surface of the rotor core at equal intervals or embedded in the rotor core. By adjusting the thickness of the stationary rotor yoke (1), the moment of inertia of the rotor meets the design requirements of different application scenarios, and the configuration difficulty of the moment of inertia is reduced. It can be seen that the function of the stationary rotor yoke is to provide a closed magnetic circuit for the rotor, that is, to replace the function of the rotor yoke in the form of a stationary element. The degree of replacement can be complete replacement or partial replacement. When the rotor has no rotor yoke at all, it is complete replacement; when the rotor retains part of the rotor yoke, it is partial replacement.

[0019] In a further embodiment, the magnetization direction of the magnetic steel (31) is axially alternating in positive and negative directions.

[0020] In a further embodiment, the cross-section of the magnetic steel (31) is fan-shaped.

[0021] In a further embodiment, the stationary rotor yoke (1) is a disc structure formed by winding silicon steel sheets to reduce losses.

[0022] In a further embodiment, the stator (2) comprises a stator core (21) and a plurality of stator windings (22), and the plurality of stator windings (22) are embedded in stator slots of the stator core (21).

[0023] In a further embodiment, the rotor core (32) comprises two circular rings, and the two circular rings are connected via rotor spokes.

[0024] In a further embodiment, Figure 2 As shown, the rotor (3) of the yoke-separated axial magnetic field motor of the present invention is of yoke-free type. A plurality of magnetic steels (31) are embedded in the spokes of the rotor core (32), and the thickness of the magnetic steels (31) is equal to the thickness of the spokes. The magnetic steels (31) are supported by the spokes, so the spokes occupy a part of the pole arc space, limiting the pole arc coefficient of the magnetic steels (31).

[0025] In a specific embodiment, the thickness of the stationary rotor yoke (1) is 11 mm, the thickness of the rotor (3) is 5.5 mm, wherein the thickness of the rotor yoke is 0 mm, and the pole arc coefficient is 0.85.

[0026] In a further embodiment, Figure 3The rotor (3) of the yoke-separated axial magnetic field motor of the present invention is in the form of a yoke. The rotor (3) comprises a plurality of magnetic steels (31) and a rotor core (32). In this case, a portion of the rotor yoke of the rotor (3) itself is arranged between two circular rings, the magnetic steel (31) is embedded between the spokes of the rotor core (32), and the bottom surface of the magnetic steel (31) is in contact with the rotor yoke, and the other surface is flush with the end surface of the rotor core (32).

[0027] Furthermore, when the thickness of the yoke of the rotor (3) is greater than a set threshold, spoke support is no longer required, and the pole arc coefficient of the magnetic steel (31) can be larger.

[0028] In a specific embodiment, the thickness of the stationary rotor yoke (1) is 9 mm, and the thickness of the rotor (3) is 7.5 mm, wherein the thickness of the rotor yoke is 2 mm, and the pole arc coefficient is 0.95. Compared with the previous embodiment, the total length of the motor remains unchanged, but the rotational inertia of the motor rotor (3) has been changed by adjusting the thickness, and the pole arc coefficient has been increased. By adjusting the thickness of the stationary rotor yoke (1) and the rotor yoke according to the requirements of different application scenarios, the rotational inertia of the rotor can be quickly and flexibly configured.

[0029] Furthermore, when the rotor has a yoke, it is made of a magnetic metal material, such as No. 10 steel; when it has no yoke, it is made of a non-magnetic metal material, such as stainless steel.

[0030] The present invention designs different stationary rotor yokes (1) and rotor yoke thicknesses according to the required rotor rotational inertia, and such changes are within the technical concept scope of the present invention.

[0031] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention.

Claims

1. A rotor yoke separation type axial magnetic field permanent magnet synchronous motor, characterized in that: The invention comprises a stationary rotor yoke (1), a stator (2) and a rotor (3), wherein the rotor (3) is arranged on a motor shaft, the rotor (3) is located between the stationary rotor yoke (1) and the stator (2), and an air gap (4) is arranged between the rotor (3) and the stationary rotor yoke (1), and between the rotor (3) and the stator (2); the stationary rotor yoke (1) is a stationary element, and the air gap between the rotor (3) and the stationary rotor yoke (1) enables the stationary rotor yoke (1) to provide a closed magnetic circuit for the rotor (3) and not to rotate with the rotor (3); the rotor (3) comprises a plurality of magnetic steels (31) and a rotor core (32), wherein the magnetic steels (31) are attached to the surface of the rotor core at equal intervals or embedded in the rotor core, and the stationary rotor yoke (1) is a disc structure formed by winding silicon steel sheets.

2. The rotor yoke separation type axial magnetic field permanent magnet synchronous motor according to claim 1, characterized in that: The magnetization direction of the magnetic steel (31) is axially alternating in positive and negative directions.

3. The rotor yoke separation type axial magnetic field permanent magnet synchronous motor according to claim 1, characterized in that: The cross section of the magnetic steel (31) is fan-shaped.

4. The rotor yoke separation type axial magnetic field permanent magnet synchronous motor according to claim 1, characterized in that: The stator (2) comprises a stator core (21) and a plurality of stator windings (22), wherein the plurality of stator windings (22) are embedded in stator slots of the stator core (21).

5. The rotor yoke separation type axial magnetic field permanent magnet synchronous motor according to claim 1, characterized in that: The rotor core (32) comprises two circular rings, and the two circular rings are connected via rotor spokes.

6. The rotor yoke separation type axial magnetic field permanent magnet synchronous motor according to claim 5, characterized in that: The rotor (3) has no yoke, and a plurality of magnetic steels (31) are embedded in the spokes of the rotor core (32), and the thickness of the magnetic steels (31) is equal to the thickness of the spokes.

7. The rotor yoke separation type axial magnetic field permanent magnet synchronous motor according to claim 5, characterized in that: The rotor (3) has a yoke, which is arranged between two circular rings. The magnetic steel (31) is embedded between the spokes of the rotor core (32), and the bottom surface of the magnetic steel (31) is in contact with the rotor yoke, while the other surface is flush with the end surface of the rotor core (32).

8. The rotor yoke separation type axial magnetic field permanent magnet synchronous motor according to claim 7, characterized in that: When the thickness of the yoke of the rotor (3) is greater than a set threshold, no spokes are required, and the magnetic steel (31) is attached to the yoke of the rotor core (32).

9. The rotor yoke separation type axial magnetic field permanent magnet synchronous motor according to claim 7, characterized in that: Different rotor rotational inertia requirements are met by adjusting the thickness of the stationary rotor yoke (1) or the thickness of the rotor (3) yoke or the thickness of the stationary rotor yoke (1) and the rotor (3) yoke.

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