High-efficiency low-noise permanent magnet synchronous motor

Abstract

The utility model relates to the field of motors, in particular to a high-efficiency low-noise permanent magnet synchronous motor, which comprises a motor stator and a motor rotor. The motor rotor comprises a rotor iron core ring and a plurality of magnetic shoes which are attached and fixed on the inner side wall of the rotor iron core ring; the motor stator is fixedly arranged in the rotor core ring, a stator core of the motor stator is provided with a plurality of winding frameworks along the circumferential direction of the stator core, and winding grooves are formed between the adjacent winding frameworks; the inner side wall surface of the magnetic tile is constructed to be a first curved surface with an arched middle part, and the outer side wall surface of the winding framework is constructed to be a second curved surface with an arched middle part; therefore, a gradually-changed air gap is formed between the magnetic shoe and the outer side wall surface of the winding framework. The synchronous motor is low in harmonic content of an air-gap magnetic field, excellent in noise, low in torque pulsation and high in demagnetization resistance, so that the problems of energy conservation, low noise, high working condition environment temperature and the like in the background technology are solved.

Description

Technical Field

[0001] The utility model relates to the field of motors, in particular to a high-efficiency and low-noise permanent magnet synchronous motor. Background Art

[0002] In recent years, the commercial fan field has been demanding energy-saving, low noise, and high ambient temperature fans. The existing AC asynchronous motors are inefficient and cannot adjust the speed. Ferrite permanent magnet synchronous motors have low noise and can adapt to high temperature environments, but they are inefficient. Figure 1 As shown, the air gap between the rotor and stator of the existing motor is usually designed to be a uniform air gap, the air gap magnetic flux waveform is basically close to a square, and the back electromotive force harmonic content is high (see attached Figure 4 The cogging torque is large (see the simulation results in the Appendix Figure 6 The simulation results shown in the figure show that there are problems such as large noise, large torque pulsation, and weak anti-demagnetization ability. Summary of the invention

[0003] In order to solve the above problems, the purpose of the utility model is to provide a high-efficiency and low-noise permanent magnet synchronous motor, which has low air gap magnetic field harmonic content, excellent noise, low torque pulsation, and strong anti-demagnetization ability, so as to solve the problems of energy saving, low noise, high working environment temperature, etc. mentioned in the above background technology.

[0004] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0005] A high-efficiency, low-noise permanent magnet synchronous motor comprises a motor stator and a motor rotor; the motor rotor comprises a rotor core ring, and a plurality of magnetic tiles fixedly attached to the inner wall of the rotor core ring; the motor stator is fixedly arranged in the rotor core ring, and the stator core of the motor stator has a plurality of winding skeletons arranged along its circumference, and winding grooves are formed between adjacent winding skeletons; it is characterized in that: the inner wall surface of the magnetic tile is constructed as a first curved surface with a raised middle portion, and the outer wall surface of the winding skeleton is constructed as a second curved surface with a raised middle portion; so that a gradual air gap is formed between the magnetic tile and the outer wall surface of the winding skeleton.

[0006] The utility model adopts the above technical solution, which relates to a high-efficiency, low-noise permanent magnet synchronous motor. The high-efficiency, low-noise permanent magnet synchronous motor is an outer rotor motor. The motor rotor includes a rotor core ring and a plurality of magnetic tiles fixed on the inner wall of the rotor core ring; the motor stator is fixed in the rotor core ring. When the motor is running, the plurality of magnetic tiles in the outer rotor core ring machine rotate at high speed.

[0007] On this basis, this solution constructs the inner wall of the magnetic tile and the outer wall of the winding frame as the first curved surface and the second curved surface respectively, and forms a gradual air gap between the magnetic tile and the outer wall of the winding frame. The motor rotor with the above-mentioned setting can make the motor air gap magnetic density waveform more sinusoidal, and the total harmonic content of the air gap magnetic density can be minimized, especially the low-order harmonics that affect the torque pulsation are significantly weakened, and the motor vibration noise is significantly improved.

[0008] Preferably, the first curved surface of the magnetic tile is eccentrically processed so that the center of the middle arc of the first curved surface is not concentric with the center of the arcs at both ends of the first curved surface, and the two ends of the first curved surface are within the radius of the middle arc. The second curved surface of the winding skeleton is eccentrically processed so that the center of the middle arc of the second curved surface is not concentric with the center of the arcs at both ends of the second curved surface, and the two ends of the second curved surface are within the radius of the middle arc. In the scheme here, both the first curved surface and the second curved surface are eccentrically processed, so that the gradual air gap has a larger gradual range of air gap length. In a specific implementation scheme, the gradual range of air gap length of the gradual air gap is 0.7mm~3.5mm.

[0009] Preferably, a mounting groove is constructed on the inner side wall of the rotor core ring, and the magnetic tile is embedded in the mounting groove. In a specific embodiment, the bottom surface of the mounting groove is constructed as a plane, and the outer end surface of the magnetic tile that is attached to the rotor core ring is also constructed as a plane.

[0010] Preferably, the thickness d1 of the two ends of the magnetic tile is ≥2.5 mm, and the thickness d2 of the middle of the magnetic tile is ≥3.5 mm.

[0011] Preferably, the pole arc coefficient of the magnetic tile is 0.69-0.72.

[0012] Preferably, the number of magnetic tiles on the inner side of the rotor core ring is 10, and the arc range L of the two ends of the magnetic tiles relative to the center of the motor stator is 24.7° to 25.7°.

[0013] Preferably, the stator core is formed by laminating a plurality of stator punching sheets, which may be formed by bonding, self-fastening, riveting and other processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The figure is a schematic diagram of the stator and rotor structure of an existing permanent magnet synchronous motor.

[0015] Figure 2 The present invention is a schematic diagram of the stator and rotor parameters of the permanent magnet synchronous motor.

[0016] Figure 3 The present invention is a schematic diagram of the stator and rotor structure of the permanent magnet synchronous motor.

[0017] Figure 4 Shown is a comparison of back EMF waveforms.

[0018] Figure 5 The output torque comparison diagram is shown.

[0019] Figure 6 Shown is a cogging torque comparison diagram. DETAILED DESCRIPTION

[0020] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0021] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "plurality" means two or more, unless otherwise clearly defined.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like 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 an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0025] like Figure 2 and 3 As shown, this embodiment relates to a high-efficiency, low-noise permanent magnet synchronous motor, including a motor stator 1 and a motor rotor 2. The motor rotor 2 includes a rotor core ring 21, and a plurality of magnetic tiles 22 fixed on the inner wall of the rotor core ring 21. The motor stator 1 is fixed in the rotor core ring 21, and the stator core of the motor stator 1 is provided with a plurality of winding skeletons 11 arranged along its circumference, and winding grooves 12 are formed between adjacent winding skeletons 11. The stator core is formed by stacking a plurality of stator punching sheets, and specifically, bonding, self-fastening, riveting and other processes can be used. The inner wall surface of the magnetic tile 22 is constructed as a first curved surface 221 with a raised middle portion, and the outer wall surface of the winding skeleton 11 is constructed as a second curved surface 111 with a raised middle portion, so that a gradual air gap 3 is formed between the magnetic tile 22 and the outer wall surface of the winding skeleton 11.

[0026] The high-efficiency, low-noise permanent magnet synchronous motor is an outer rotor motor, and the motor rotor 2 includes a rotor core ring 21, and a plurality of magnetic tiles 22 fixed on the inner wall of the rotor core ring 21. The motor stator 1 is fixed in the rotor core ring 21. When the motor is running, the plurality of magnetic tiles 22 in the rotor core ring 21 on the outside rotate at high speed. On this basis, the inner wall surface of the magnetic tile 22 and the outer wall surface of the winding skeleton 11 are respectively constructed as a first curved surface 221 and a second curved surface 111 in this scheme, and a gradual air gap 3 is formed between the magnetic tile 22 and the outer wall surface of the winding skeleton 11. The motor rotor 2 with the above-mentioned setting can make the motor air gap magnetic density waveform more sinusoidal, and the total harmonic content of the air gap magnetic density can be minimized, especially the low-order harmonics that affect the torque pulsation are significantly weakened, and the vibration noise of the motor is significantly improved.

[0027] like Figure 2As shown, the first curved surface 221 of the magnetic tile 22 is processed eccentrically: the center of the middle arc of the first curved surface 221 is not concentric with the center of the arcs at both ends of the first curved surface 221, and the two ends of the first curved surface 221 are within the radius of the middle arc. The second curved surface 111 of the winding skeleton 11 is processed eccentrically: the center of the middle arc of the second curved surface 111 is not concentric with the center of the arcs at both ends of the second curved surface 111, and the two ends of the second curved surface 111 are within the radius of the middle arc. Figure 2 For example, the radius of the middle curvature of the second curved surface 111 is R3, and the radius of the curvature of the curvature at both ends of the second curved surface 111 is R4. The two are not concentric, and the eccentricity is R0. As can be seen from the figure, the two ends of the second curved surface 111 are located within the range of radius R3. In the scheme here, both the first curved surface 221 and the second curved surface 111 are eccentrically processed, so that the gradual range of the air gap length of the gradual air gap 3 is larger. In a specific implementation scheme, the gradual range of the air gap length of the gradual air gap 3 is 0.7mm to 3.5mm.

[0028] like Figure 2 As shown, a mounting groove 23 is constructed on the inner wall of the rotor core ring 21, and the magnetic tile 22 is embedded in the mounting groove 23. In a specific implementation scheme, the bottom surface of the mounting groove 23 is constructed as a plane, and the outer end surface of the magnetic tile 22 that is in contact with the rotor core ring 21 is also constructed as a plane 222. The thickness d1 at both ends of the magnetic tile 22 is ≥2.5mm, and the thickness d2 in the middle of the magnetic tile 22 is ≥3.5mm. The pole arc coefficient of the magnetic tile 22 is 0.69~0.72. Specifically, the number of magnetic tiles 22 on the inner side of the rotor core ring 21 is 10, and the arc range L of the two ends of the magnetic tile 22 relative to the center of the motor stator 1 is 24.7°~25.7°.

[0029] Adopt the above scheme recorded in this embodiment and Figure 1 The prior art solution shown in the figure is simulated and tested. Figure 4-6 As shown, the following conclusions are drawn:

[0030] See attached Figure 4 The back EMF waveform comparison diagram shown shows that the original solution has high harmonic content, and the back EMF waveform after optimization is closer to a sine wave;

[0031] See attached Figure 5 The output torque comparison diagram shown shows that the torque output fluctuation is 24% before the scheme optimization, and 2.76% after the optimization;

[0032] like Figure 6 As shown in the cogging torque comparison diagram, the cogging torque was 1316 mN.m before the optimization and 31.72 mN.m after the optimization, which is a reduction of 97.5% after the optimization.

[0033] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0034] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention.

Claims

1. A high-efficiency, low-noise permanent magnet synchronous motor, comprising a motor stator (1) and a motor rotor (2); the motor rotor (2) comprises a rotor core ring (21), and a plurality of magnetic tiles (22) fixedly attached to the inner side wall of the rotor core ring (21); the motor stator (1) is fixedly arranged in the rotor core ring (21), and the stator core of the motor stator (1) is provided with a plurality of winding skeletons (11) arranged along its circumference, and winding grooves (12) are formed between adjacent winding skeletons (11); the characteristics are: The inner wall surface of the magnetic tile (22) is constructed as a first curved surface (221) with a raised middle portion, and the outer wall surface of the winding frame (11) is constructed as a second curved surface (111) with a raised middle portion, so that a gradual air gap (3) is formed between the magnetic tile (22) and the outer wall surface of the winding frame (11).

2. A high-efficiency, low-noise permanent magnet synchronous motor according to claim 1, characterized in that: The first curved surface (221) of the magnetic tile (22) is processed eccentrically so that the center of the middle arc of the first curved surface (221) is not concentric with the center of the arcs at both ends of the first curved surface (221), and the two ends of the first curved surface (221) are within the radius of the middle arc; the second curved surface (111) of the winding skeleton (11) is processed eccentrically so that the center of the middle arc of the second curved surface (111) is not concentric with the center of the arcs at both ends of the second curved surface (111), and the two ends of the second curved surface (111) are within the radius of the middle arc.

3. A high-efficiency, low-noise permanent magnet synchronous motor according to claim 2, characterized in that: The gradual change range of the air gap length of the gradual change type air gap (3) is 0.7 mm to 3.5 mm.

4. The high-efficiency and low-noise permanent magnet synchronous motor according to claim 1, characterized in that: An installation groove (23) is constructed on the inner side wall of the rotor core ring (21), and the magnetic tile (22) is embedded in the installation groove (23).

5. A high-efficiency, low-noise permanent magnet synchronous motor according to claim 4, characterized in that: The bottom surface of the installation groove (23) is constructed as a plane (222), and the outer end surface of the magnetic tile (22) that is in contact with the rotor core ring (21) is also constructed as a plane (222).

6. A high-efficiency, low-noise permanent magnet synchronous motor according to claim 4, characterized in that: The thickness d1 of the two ends of the magnetic tile (22) is ≥2.5 mm, and the thickness d2 of the middle of the magnetic tile (22) is ≥3.5 mm.

7. The high-efficiency and low-noise permanent magnet synchronous motor according to claim 1, characterized in that: The pole arc coefficient of the magnetic tile (22) is 0.69-0.

72.

8. The high-efficiency, low-noise permanent magnet synchronous motor according to claim 7, characterized in that: The number of magnetic tiles (22) inside the rotor core ring (21) is 10, and the arc range L of the two ends of the magnetic tiles (22) relative to the center of the motor stator (1) is 24.7° to 25.7°.

9. The high-efficiency, low-noise permanent magnet synchronous motor according to claim 1, characterized in that: The stator core is formed by laminating a plurality of stator punching sheets.

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