Permanent magnet motor rotor and permanent magnet motor

Abstract

The present invention discloses a permanent magnet motor rotor and a permanent magnet motor. The permanent magnet motor rotor comprises: a rotor core, V-shaped magnetic steel slots uniformly arranged on the rotor core, and magnetic steels assembled on the V-shaped magnetic steel slots; a magnetic bridge protrusion is provided on the rotor core, and the magnetic bridge protrusion is arranged at a position close to the rotor q axis outside the V-shaped magnetic steel slots. The permanent magnet motor rotor optimizes the shape of the magnetic bridge, thereby optimizing the motor magnetic circuit, reducing the iron loss under various working conditions, thereby greatly improving the motor driving efficiency and motor speed, and meeting the driving requirements of new energy vehicles.

Description

Technical Field

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

[0002] With the development of new energy vehicles, new energy vehicles have put forward increasingly higher requirements on various aspects of the performance of the drive motor (such as the efficiency, speed and NVH performance of the drive motor).

[0003] At present, the rotor structure of the drive motor generally adopts a rotor structure with a single "V"-shaped magnetic steel arrangement. Among them, each magnetic pole in the rotor structure with a single "V"-shaped magnetic steel arrangement includes two magnetic steels arranged in a "V" shape. However, the rotor structure with a single "V"-shaped magnetic steel arrangement currently has the following problems:

[0004] 1) The weight of a single magnetic steel is relatively high, making it difficult to solve the rotor strength problem at high speeds;

[0005] 2) The ability to resist armature reaction is weak. Under deep weak magnetic conditions, the magnetic field distortion is large and the harmonic content increases, resulting in increased motor iron loss and reduced efficiency of the drive motor. Summary of the invention

[0006] In order to solve the above technical problems, the current rotor structure with a single "V"-shaped magnetic steel arrangement has a large motor iron loss and low efficiency in driving the motor.

[0007] An embodiment of the present invention provides a permanent magnet motor rotor, comprising: a rotor core, V-shaped magnetic steel slots evenly arranged on the rotor core, and magnetic steels assembled on the V-shaped magnetic steel slots; a magnetic bridge protrusion is provided on the rotor core, and the magnetic bridge protrusion is arranged on the outer side of the V-shaped magnetic steel slots close to the rotor q axis.

[0008] Preferably, the V-shaped magnetic steel groove includes a first V-shaped magnetic steel groove and a second V-shaped magnetic steel groove; a first distance from the first V-shaped magnetic steel groove to the edge of the rotor core is greater than a second distance from the second V-shaped magnetic steel groove to the edge of the rotor core.

[0009] Preferably, the included angle range of the first V-shaped magnetic steel groove is 82°-125°.

[0010] Preferably, the included angle range of the second V-shaped magnetic steel groove is 140°-160°.

[0011] Preferably, the magnetic bridge protrusion is an arc-shaped protrusion.

[0012] Preferably, the rotor core is provided with a first circular arc recess extending from one end of the magnetic bridge protrusion and a second circular arc recess extending from the other end of the magnetic bridge protrusion.

[0013] Preferably, the angle between the line connecting the center of the arc-shaped protrusion and the center of the rotor core and the rotor d-axis is in the range of 15°-17°.

[0014] Preferably, the diameter range of the arc-shaped protrusion is 1 / 3-4 / 5 of the length of the air gap contour line of the V-shaped magnetic steel groove facing the air gap side.

[0015] Preferably, the area of ​​the arc-shaped protrusion accounts for 2 / 3-1 / 5 of the area of ​​the circle.

[0016] The permanent magnet motor rotor disclosed in the present invention comprises a rotor core, V-shaped magnetic steel slots uniformly arranged on the rotor core, and magnetic steels assembled on the V-shaped magnetic steel slots. A magnetic bridge protrusion is provided on the rotor core, and the magnetic bridge protrusion is arranged at a position close to the rotor q axis outside the V-shaped magnetic steel slot to optimize the shape of the magnetic bridge, thereby optimizing the motor magnetic circuit, reducing the iron loss under various working conditions, thereby greatly improving the motor driving efficiency and motor speed, and meeting the driving requirements of new energy vehicles.

[0017] An embodiment of the present invention provides a permanent magnet motor, comprising a permanent magnet motor stator and the permanent magnet motor rotor as described above.

[0018] The permanent magnet motor disclosed in the present invention comprises a permanent magnet motor stator and the above-mentioned permanent magnet motor rotor. The iron loss, torque fluctuation and motor noise of the permanent magnet motor under various working conditions can be effectively reduced, and the motor performance is improved, thereby meeting the trend of high-speed drive motors for new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0020] Figure 1 is a schematic diagram of a permanent magnet motor rotor in one embodiment of the present invention;

[0021] Figure 2 is another schematic diagram of a permanent magnet motor rotor according to an embodiment of the present invention;

[0022] 1. Rotor core; 11. Rotor q axis; 12. Rotor d axis; 2. Magnetic bridge protrusion; 21. First arc recess; 22. Second arc recess; 23. Vertical short side line; 31. First V-shaped magnetic steel groove; 32. Second V-shaped magnetic steel groove; A. Rotor core center; a. Center standard line; 41. First magnetic steel; 42. Second magnetic steel; 5. Air gap contour line. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] In the description of the present invention, it should be understood that the terms "longitudinal", "radial", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 indirectly connected 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.

[0026] The present invention provides a permanent magnet motor rotor, such as Figure 1 As shown, the permanent magnet motor rotor includes a rotor core 1, V-shaped magnetic steel slots evenly arranged on the rotor core 1, and magnetic steels assembled on the V-shaped magnetic steel slots; a magnetic bridge protrusion 2 is provided on the rotor core 1, and the magnetic bridge protrusion 2 is arranged on the outer side of the V-shaped magnetic steel slot close to the rotor q axis 11.

[0027] Specifically, the figure shows a specific schematic diagram of a magnetic pole in the permanent magnet motor rotor in this embodiment. The permanent magnet motor rotor includes at least one magnetic pole, which is evenly distributed on the rotor core 1 along the circumferential direction of the rotor. Each magnetic pole includes a V-shaped magnetic steel slot and a magnetic steel assembled on the V-shaped magnetic steel slot. A magnetic bridge protrusion 2 is provided on the rotor core 1 near the rotor q axis 11 to optimize the shape of the magnetic bridge, thereby optimizing the motor magnetic circuit and reducing the iron loss under various working conditions.

[0028] Among them, the magnetic steel is a rectangular parallelepiped with rounded edges. At the same time, the area where the magnetic steel is assembled in the V-shaped magnetic steel groove matches the shape of the magnetic steel, so that the magnetic steel can be assembled on the V-shaped magnetic steel groove, thereby dispersing stress and ensuring the stamping life of the mold.

[0029] Understandably, under high-speed weak magnetic conditions or no-load conditions, the magnetic field inside the motor is relatively weak, and the magnetic bridge protrusion 2 widens the magnetic bridge, weakening the main magnetic field at this time, thereby reducing the iron loss caused by the main magnetic field. Under high-torque conditions, the magnetic field inside the motor is relatively strong, and the magnetic flux of the magnetic bridge part after optimizing the shape of the magnetic bridge is saturated, limiting the leakage magnetic flux, and the main magnetic field and the stator magnetic field can be fully linked, so the motor torque can be fully exerted and is less affected by the magnetic bridge protrusion 2. Among them, the magnetic field inside the motor includes the main magnetic field and the stator magnetic field; the main magnetic field is the magnetic field generated by the rotor; the stator magnetic field is the magnetic field generated by the stator.

[0030] In this embodiment, the permanent magnet motor rotor includes a rotor core 1, V-shaped magnetic steel slots uniformly arranged on the rotor core 1, and magnetic steels assembled on the V-shaped magnetic steel slots. By providing a magnetic bridge protrusion 2 on the rotor core 1, the magnetic bridge protrusion 2 is arranged at a position close to the rotor q axis 11 outside the V-shaped magnetic steel slot to optimize the shape of the magnetic bridge, thereby optimizing the motor magnetic circuit, reducing the iron loss under various working conditions, thereby greatly improving the motor driving efficiency and motor speed, and meeting the driving requirements of new energy vehicles.

[0031] In one embodiment, if Figure 1 As shown, the V-shaped magnetic steel slot includes a first V-shaped magnetic steel slot 31 and a second V-shaped magnetic steel slot 32; a first distance from the first V-shaped magnetic steel slot 31 to the edge of the rotor core 1 is greater than a second distance from the second V-shaped magnetic steel slot 32 to the edge of the rotor core 1.

[0032] Specifically, the V-shaped magnetic steel slot includes a first V-shaped magnetic steel slot 31 and a second V-shaped magnetic steel slot 32. The first distance from the first V-shaped magnetic steel slot 31 to the edge of the rotor core 1 is greater than the second distance from the second V-shaped magnetic steel slot 32 to the edge of the rotor core 1. The first V-shaped magnetic steel slot 31 is equipped with a first magnetic steel 41, and the second V-shaped magnetic steel slot 32 is equipped with a second magnetic steel 42 to form a double-layer V-shaped rotor structure. The double-layer V-shaped rotor structure can effectively reduce the weight of a single magnetic steel, and the multiple layers of magnetic steel can stabilize the magnetic field distribution under load, and at the same time can effectively enhance the ability to resist armature reaction and anti-demagnetization.

[0033] It should be noted that, since the installation space of the second V-shaped magnetic steel slot 32 is limited, the magnetic bridge protrusion 2 can be arranged at a position outside the first V-shaped magnetic steel slot 31 close to the rotor q-axis 11 .

[0034] In this embodiment, a double-layer V-shaped rotor structure is combined with a magnetic bridge with an optimized shape to effectively reduce the sinusoidal distortion rate of the magnetic field waveform and the harmonic component of the magnetic field, thereby reducing iron losses. At the same time, since the sinusoidal distortion rate of the magnetic field waveform is reduced, the amplitude of the rotor harmonic magnetic field is reduced, thereby reducing the radial electromagnetic force of the motor, thereby greatly weakening the noise of the motor.

[0035] In one embodiment, if Figure 1 and Figure 2 As shown, the included angle range of the first V-shaped magnetic steel groove 31 is 82°-125°.

[0036] Specifically, the angle range of the first V-shaped magnetic steel groove 31 is as follows: Figure 2 The angle α shown in the figure ranges from 82° to 125°, so as to effectively reduce the sinusoidal distortion rate of the magnetic field waveform, that is, reduce the amplitude of the rotor harmonic magnetic field, thereby reducing the radial electromagnetic force of the motor, and thus greatly reducing the noise of the motor.

[0037] In this embodiment, in order to further reduce the motor noise, the angle range of the first V-shaped magnetic steel slot 31 is preferably 90°~118° to enhance the motor noise reduction effect.

[0038] In one embodiment, if Figure 1 and Figure 2 As shown, the included angle range of the second V-shaped magnetic steel groove 32 is 140°-160°.

[0039] Specifically, the angle range of the second V-shaped magnetic steel slot 32, as shown in the figure, is 82°-125°, so as to effectively reduce the sinusoidal distortion rate of the magnetic field waveform, that is, reduce the amplitude of the rotor harmonic magnetic field, thereby reducing the radial electromagnetic force of the motor, and thus greatly weakening the noise of the motor.

[0040] In this embodiment, in order to further reduce the motor noise, the angle range of the second V-shaped magnetic steel groove 32 is preferably 90°~118° to enhance the motor noise reduction effect.

[0041] In one embodiment, if Figure 1 and Figure 2 As shown, the magnetic bridge protrusion 2 is an arc-shaped protrusion.

[0042] In this embodiment, the magnetic bridge protrusion 2 is designed as an arc-shaped protrusion to optimize the shape of the magnetic bridge, reduce the torque fluctuation of the motor, increase the motor's ability to resist armature reaction, reduce the iron loss of the motor under high-speed conditions, and greatly improve the motor efficiency.

[0043] In addition, by designing the magnetic bridge protrusion 2 as an arc-shaped protrusion, the transition step stress can be effectively reduced while ensuring the stamping life of the mold.

[0044] In one embodiment, if Figure 1 and Figure 2 As shown, the rotor core 1 is provided with a first arc recessed position 21 extending from one end of the magnetic bridge protrusion 2 and a second arc recessed position 22 extending from the other end of the magnetic bridge protrusion 2 .

[0045] In this embodiment, the optimized magnetic bridge shape also includes a first arc recessed position 21 extending from one end of the arc-shaped protrusion and a second arc recessed position 22 extending from the other end of the magnetic bridge protrusion 2, so as to form a magnetic bridge with an optimized shape by combining the magnetic bridge protrusion 2, the first arc recessed position 21, the second arc recessed position 22 and a vertical short side line 23 tangent to the second arc recessed position 22, so as to constrain the direction of the magnetic lines of force of part of the magnetic bridge, thereby optimizing the motor magnetic circuit, reducing the motor torque fluctuation, and at the same time reducing the radial electromagnetic force, thereby greatly weakening the noise of the motor.

[0046] Furthermore, the first arc recessed position 21 is connected to the chamfered corner of the V-shaped magnetic steel groove, and the magnetic bridge protrusion 2 is respectively connected to the first arc recessed position 21 and the second arc recessed position 22 through arc transition, which can effectively disperse the stress and ensure the stamping life of the mold.

[0047] In one embodiment, if Figure 1 and Figure 2 As shown, the angle between the line connecting the center of the arc-shaped protrusion and the center A of the rotor core and the rotor d axis 12 is in the range of 15°-17°.

[0048] In this embodiment, the line connecting the center of the arc-shaped protrusion and the center A of the rotor core (assuming it is point A in the figure) is used as the center standard line a (that is, as shown by the dotted line a in the figure) and the angle range θ with the rotor d axis 12 is between 15° and 17°, so as to optimize the motor magnetic circuit, effectively improve the motor torque, reduce torque fluctuation, reduce radial electromagnetic force, weaken the noise of the motor, and optimize the motor performance.

[0049] Furthermore, the angle between the line connecting the center of the arc-shaped protrusion and the center A of the rotor core and the rotor d axis 12 is preferably 16°, so as to better achieve the technical effects of increasing the motor torque, reducing torque fluctuations, reducing radial electromagnetic force, and weakening the noise of the motor.

[0050] In one embodiment, if Figure 1 and Figure 2 As shown, the diameter range of the arc-shaped protrusion is 1 / 3-4 / 5 of the length of the air gap contour line 5 of the V-shaped magnetic steel groove facing the air gap side.

[0051] The air gap contour line 5 specifically refers to a side contour line of the V-shaped magnetic steel groove facing the air gap side. For example, Figure 2 The straight length of one side of the first V-shaped magnetic steel slot 31 facing the air gap side shown. The air gap side specifically refers to the part of the rotor core 1 outside the figure, where the opening of the V-shaped magnetic steel slot faces. In this embodiment, the diameter range of the circle corresponding to the arc-shaped protrusion is 1 / 3-4 / 5 of the length of the air gap contour line 5 of the V-shaped magnetic steel slot facing the air gap side, so as to optimize the motor magnetic circuit, effectively increase the motor torque, reduce the motor torque fluctuation, and reduce the radial electromagnetic force, thereby reducing the noise of the motor.

[0052] Furthermore, the diameter range of the arc-shaped protrusion is preferably 2 / 5-4 / 5 of the length of the V-shaped magnetic steel groove toward the air gap contour line 5, so as to better achieve the technical effects of increasing the motor torque, reducing torque fluctuations, reducing radial electromagnetic force, and weakening the noise of the motor.

[0053] In one embodiment, if Figure 1 and Figure 2 As shown, the area of ​​the arc-shaped protrusion occupies 2 / 3-1 / 5 of the area of ​​the corresponding circle.

[0054] In this embodiment, the area of ​​the arc-shaped protrusion accounts for 2 / 3-1 / 5 of the area of ​​the corresponding circle, so as to optimize the motor magnetic circuit, effectively increase the motor torque, reduce the motor torque fluctuation, and reduce the radial electromagnetic force, thereby reducing the noise of the motor. , r is the radius of the circle corresponding to the arc-shaped protrusion, that is, 1 / 2 of the diameter of the circle corresponding to the arc-shaped protrusion.

[0055] Furthermore, the area of ​​the arc-shaped protrusion is preferably 1 / 2-1 / 5 of the area of ​​its corresponding circle, so as to better achieve the technical effects of increasing the motor torque, reducing the motor torque fluctuation, reducing the radial electromagnetic force, and weakening the noise of the motor.

[0056] In this embodiment, by optimizing the shape of the magnetic bridge and the V-shaped magnetic steel groove, and optimizing multiple parameter factors of the magnetic bridge protrusion 2 and the V-shaped magnetic steel groove, namely the area of ​​the magnetic bridge protrusion 2, the diameter of its corresponding circle, the center of the circle and the angle of the V-shaped magnetic steel groove, the NVH performance, motor power and motor speed of the motor are greatly improved, and the problem that the optimization parameters in the existing rotor topology structure are relatively single and it is difficult to finely optimize the magnetic circuit design according to design requirements can be effectively solved.

[0057] The present invention provides a permanent magnet motor, comprising a permanent magnet motor stator and the permanent magnet motor rotor as described above.

[0058] In this embodiment, the permanent magnet motor includes a permanent magnet motor stator and a permanent magnet motor rotor as described above, which is mounted on the permanent magnet motor stator. The iron loss, torque fluctuation and motor noise of the permanent magnet motor under various working conditions can be effectively reduced, and the motor performance is improved, thereby meeting the trend of high-speed drive motors for new energy vehicles.

[0059] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A permanent magnet motor rotor, characterized in that: include: A rotor core, V-shaped magnetic steel grooves uniformly arranged on the rotor core, and magnetic steels mounted on the V-shaped magnetic steel grooves; a magnetic bridge protrusion is provided on the rotor core, and the magnetic bridge protrusion is arranged in the V-shaped magnetic steel groove and close to the rotor q axis; The magnetic bridge protrusion is an arc-shaped protrusion, and the rotor core is provided with a first arc-shaped recessed position extending from one end of the magnetic bridge protrusion and a second arc-shaped recessed position extending from the other end of the magnetic bridge protrusion, and the other end of the second arc-shaped recessed position is connected with a vertical short side line to form a right-angle transition; The angle between the line connecting the center of the arc-shaped protrusion and the center of the rotor core and the rotor d axis is in the range of 15°-17°; the diameter range of the arc-shaped protrusion is 1 / 3-4 / 5 of the length of the air gap contour line of the V-shaped magnetic steel groove toward the air gap side; the area of ​​the arc-shaped protrusion accounts for 2 / 3-1 / 5 of the area of ​​the corresponding circle.

2. The permanent magnet motor rotor according to claim 1, characterized in that: The V-shaped magnetic steel slot includes a first V-shaped magnetic steel slot and a second V-shaped magnetic steel slot; a first distance from the first V-shaped magnetic steel slot to the edge of the rotor core is greater than a second distance from the second V-shaped magnetic steel slot to the edge of the rotor core.

3. The permanent magnet motor rotor according to claim 2, characterized in that: The included angle range of the first V-shaped magnetic steel groove is 82°-125°.

4. The permanent magnet motor rotor according to claim 2, characterized in that: The included angle range of the second V-shaped magnetic steel groove is 140°-160°.

5. A permanent magnet motor, characterized in that: It comprises a permanent magnet motor stator and a permanent magnet motor rotor as claimed in any one of claims 1 to 4.

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