Stacked rotor structure of permanent magnet synchronous motor and permanent magnet synchronous motor

Abstract

The permanent magnet synchronous motor stacked rotor structure provided by the utility model comprises the main rotor assembly and the auxiliary rotor assembly, the main rotor assembly comprises the main rotor body and the main rotor permanent magnets, the main rotor permanent magnets are embedded in the main rotor body to form a built-in permanent magnet synchronous motor rotor structure, and reluctance torque is caused through a motor salient pole effect, so that the permanent magnet synchronous motor is formed. The auxiliary rotor assembly is arranged on the two sides of the main rotor body and comprises an auxiliary rotor body and an auxiliary rotor permanent magnet, the auxiliary rotor permanent magnet is arranged on the auxiliary rotor body, and the auxiliary rotor assembly forms a surface-mounted permanent magnet synchronous motor rotor structure, so that magnetic leakage of the permanent magnet can be effectively reduced, and harmonic torque with the average torque being zero is generated; the main rotor assembly is used for offsetting the torque ripple generated by the main rotor assembly, and can reduce the torque ripple of the output torque, improve the quality of the output torque of the motor and prolong the service life of the motor on the premise that the output torque is not reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of motors, and specifically relates to a permanent magnet synchronous motor stacked rotor structure and a permanent magnet synchronous motor. Background Art

[0002] With the continuous improvement of motor design and manufacturing capabilities and people's continuous demand for high-quality motors, it has the advantages of simple structure, high power density, high efficiency and energy saving, and easy control. However, due to the use of permanent magnet excitation in permanent magnet motors, there is cogging torque when it is unloaded; when loaded, the magnetic field generated by the permanent magnet magnetic field and the stator current interact with each other, and when generating effective average torque, additional harmonic torque will be generated. Cogging torque and harmonic torque together constitute the pulsating part of the output torque, which is generally called torque pulsation. The torque pulsation of permanent magnet synchronous motors is closely related to the vibration noise of the motor. Large torque pulsation will significantly increase the vibration noise level of the motor. Long-term operation of the motor under severe vibration conditions will further accelerate the aging of the motor and reduce the service life of the motor.

[0003] To solve the above problems, patent document CN112688511A proposes an asymmetric integrated rotor permanent magnet synchronous reluctance motor, method and application, including: a rotor and a stator, wherein the rotor is integrated by a surface-mounted permanent magnet synchronous motor rotor and two synchronous reluctance motor rotors, and the surface-mounted permanent magnet synchronous motor rotor is sandwiched between the two synchronous reluctance motor rotors; the surface-mounted permanent magnet synchronous motor rotor and the synchronous reluctance motor rotor are configured with an installation angle so that the maximum values ​​of the permanent magnet torque and the reluctance torque of the motor can be superimposed at the same current phase angle, but the above problems cannot be solved. Utility Model Content

[0004] The utility model is designed to solve the above problems, and aims to provide a permanent magnet synchronous motor stacked rotor structure and a permanent magnet synchronous motor which can reduce the torque pulsation of the output torque without reducing the output torque, have high motor output torque quality, and have a long motor service life. In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] The utility model provides a permanent magnet synchronous motor stacked rotor structure, which has the following characteristics: a main rotor assembly, comprising a main rotor body and a main rotor permanent magnet, wherein the main rotor permanent magnet is embedded in the main rotor body; and a sub-rotor assembly, which is arranged on both sides of the main rotor body and comprises a sub-rotor body and a sub-rotor permanent magnet, wherein the sub-rotor permanent magnet is arranged on the sub-rotor body.

[0006] The stacked rotor structure of the permanent magnet synchronous motor provided by the present invention may also have the following features: the main rotor body is cylindrical, and a main rotor shaft hole is provided on the main rotor body.

[0007] The stacked rotor structure of the permanent magnet synchronous motor provided by the present invention may also have the following features: the auxiliary rotor body is in a disc shape, and an auxiliary rotor shaft hole is provided on the auxiliary rotor body.

[0008] The stacked rotor structure of the permanent magnet synchronous motor provided by the present invention may also have the following features: the diameters of the main rotor body and the auxiliary rotor body are the same, and the apertures of the main rotor shaft hole and the auxiliary rotor shaft hole are the same.

[0009] In the permanent magnet synchronous motor stacked rotor structure provided by the utility model, it can also have the following characteristics: the auxiliary rotor permanent magnets are evenly distributed on the auxiliary rotor body, and the number and polarity of the auxiliary rotor permanent magnets match the amplitude and order of the torque pulsation generated by the main rotor assembly.

[0010] The stacked rotor structure of the permanent magnet synchronous motor provided by the present invention may also have the following feature: the ratio of the core length of the auxiliary rotor assembly to the core length of the main rotor assembly is in the range of 5% to 10%.

[0011] The stacked rotor structure of the permanent magnet synchronous motor provided by the present invention may also have the following feature: the installation angle between the main rotor body and the auxiliary rotor body matches the phase of the torque pulsation generated by the main rotor assembly.

[0012] The stacked rotor structure of the permanent magnet synchronous motor provided by the present invention may also have the following feature: the main rotor body and the auxiliary rotor body are both formed by stacking silicon steel sheets.

[0013] The stacked rotor structure of the permanent magnet synchronous motor provided by the present invention may also have the following feature: the auxiliary rotor permanent magnet is a neodymium iron boron permanent magnet.

[0014] The utility model also provides a generator having the following characteristics, comprising the above-mentioned permanent magnet synchronous motor stacked rotor structure.

[0015] The technical effect of the utility model is as follows: the permanent magnet synchronous motor stacked rotor structure provided by the utility model includes a main rotor assembly and a sub-rotor assembly, the main rotor assembly includes a main rotor body and a main rotor permanent magnet, the main rotor permanent magnet is embedded in the main rotor body to form a built-in permanent magnet synchronous motor rotor structure, and the magnetic resistance torque is caused by the motor salient pole effect to improve the motor torque density, the sub-rotor assembly is arranged on both sides of the main rotor body, including a sub-rotor body and a sub-rotor permanent magnet, the sub-rotor permanent magnet is arranged on the sub-rotor body, and the sub-rotor assembly forms a surface-mounted permanent magnet synchronous motor rotor structure, which can effectively reduce permanent magnet leakage and generate harmonic torque with an average torque of zero, which is used to offset the torque pulsation generated by the main rotor assembly.

[0016] Therefore, the stacked rotor structure of the permanent magnet synchronous motor provided by the utility model can reduce the torque pulsation of the output torque, improve the output torque quality of the motor, and extend the service life of the motor without reducing the output torque. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] This specification includes the following drawings, which show the following contents:

[0018] Figure 1 is an exploded view of a stacked rotor structure of a permanent magnet synchronous motor in an embodiment of the utility model;

[0019] Figure 2 is a torque waveform diagram of a finite element simulation of a main rotor assembly in an embodiment of the utility model;

[0020] Figure 3 is a torque waveform diagram of a finite element simulation of a secondary rotor assembly in an embodiment of the utility model;

[0021] Figure 4 It is a torque waveform diagram of the finite element simulation of the stacked rotor structure of the permanent magnet synchronous motor in the embodiment of the utility model.

[0022] Markings in the figure are: 10-main rotor assembly, 11-main rotor body, 12-main rotor permanent magnet, 13-main rotor shaft hole, 20-auxiliary rotor assembly, 21-auxiliary rotor body, 22-auxiliary rotor permanent magnet, 23-auxiliary rotor shaft hole. DETAILED DESCRIPTION

[0023] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention and facilitating their implementation.

[0024] Figure 1 It is an exploded view of the stacked rotor structure of the permanent magnet synchronous motor in the embodiment of the utility model.

[0025] like Figure 1 As shown, the permanent magnet synchronous motor stacked rotor structure provided by the present invention includes a main rotor assembly 10 and a sub-rotor assembly 20 .

[0026] The main rotor assembly 10 includes a main rotor body 11 and a main rotor permanent magnet 12. The main rotor permanent magnet 12 is embedded in the main rotor body 11 to form a built-in permanent magnet synchronous motor rotor structure. The motor salient pole effect causes magnetic resistance torque, thereby increasing the motor torque density and thus increasing the output torque.

[0027] Two auxiliary rotor assemblies 20 are arranged on both sides of the main rotor body 11, and a three-layer stacking structure of auxiliary rotor-main rotor-auxiliary rotor is formed between the two auxiliary rotor assemblies 20 and the main rotor assembly 10. The auxiliary rotor assembly 20 includes an auxiliary rotor body 21 and an auxiliary rotor permanent magnet 22. The auxiliary rotor permanent magnet 22 is arranged on the auxiliary rotor body 21, and the auxiliary rotor permanent magnet 22 is evenly distributed around the peripheral edge of the auxiliary rotor body 21. The auxiliary rotor assembly 20 forms a surface-mounted permanent magnet synchronous motor rotor structure, which can effectively reduce permanent magnet leakage and generate harmonic torque with an average torque of zero, which is used to offset the torque pulsation generated by the main rotor assembly 10.

[0028] like Figure 1 As shown, the main rotor assembly 10 has a 48-slot structure and the number of poles of the main rotor assembly 10 is 8.

[0029] The main rotor body 11 is cylindrical, and a main rotor shaft hole 13 is provided on the main rotor body 11. The auxiliary rotor body 21 is disc-shaped, and an auxiliary rotor shaft hole 23 is provided on the auxiliary rotor body 21. The main rotor body 11 and the auxiliary rotor body 21 have the same diameter, and the main rotor shaft hole 13 and the auxiliary rotor shaft hole 23 have the same aperture. The main rotor body and the auxiliary rotor body are both laminated silicon steel sheets, and the diameters of the main rotor body 11 and the auxiliary rotor body 21 are 162.25 mm, and the apertures of the main rotor shaft hole 13 and the auxiliary rotor shaft hole 23 are 111.5 mm, which is convenient for installing the stacked rotor structure of the permanent magnet synchronous motor.

[0030] The auxiliary rotor permanent magnet 22 is a neodymium iron boron permanent magnet, and the main rotor permanent magnet 12 can adopt various permanent magnets to conveniently provide the required torque. The neodymium iron boron permanent magnet can effectively reduce the core length of the auxiliary rotor permanent magnet 22, thereby reducing the overall axial length of the rotor.

[0031] The auxiliary rotor permanent magnets 22 are evenly distributed on the auxiliary rotor body 21. The number and polarity of the auxiliary rotor permanent magnets 22 match the amplitude and order of the torque pulsation generated by the main rotor assembly 10, that is, the amplitude and order of the torque pulsation to be suppressed. In this embodiment, the polarity under a pair of poles of the main rotor assembly 10 is "NSNSNSNSNSNSSNSNSNSNSNSNSN". In order to suppress the 96th torque pulsation harmonic of the 12th order generated by the main rotor assembly 10, the number of the auxiliary rotor permanent magnets 22 is 96, and the 96 auxiliary rotor permanent magnets 22 are evenly distributed on the auxiliary rotor body 21. The length of the long side of the auxiliary rotor permanent magnet 22 is 5.15 mm, and the length of the short side is 2 mm.

[0032] The ratio of the core length of the auxiliary rotor assembly 20 to the core length of the main rotor assembly 10 is in the range of 5% to 10%. In the present embodiment, the core length of the auxiliary rotor assembly 20 is 3.10 mm, the core length of the main rotor assembly 10 is 50.8 mm, and the ratio of the core length of the auxiliary rotor assembly 20 to the core length of the main rotor assembly 10 is 6.10%.

[0033] The installation angle between the main rotor body 11 and the auxiliary rotor body 21 in the circumferential direction matches the phase of the torque pulsation generated by the main rotor assembly 10, that is, the phase of the torque pulsation to be suppressed. In this embodiment, the installation angle between the main rotor body 11 and the auxiliary rotor body 21 in the circumferential direction is 0°.

[0034] Figure 2 It is a torque waveform diagram of the finite element simulation of the main rotor assembly in the embodiment of the utility model.

[0035] like Figure 2 As shown in the torque waveform diagram of the finite element simulation of the main rotor assembly 10, the simulation time is one electrical cycle, that is, the main rotor assembly 10 rotates through a 90° mechanical angle. In the torque waveform diagram, the average torque is 178.83 Nm, the maximum torque is 193.66 Nm, the minimum torque is 165.73 Nm, and the torque ripple is 15.62%. In addition, Figure 2 It can be found that the order of torque ripple is 12th.

[0036] Figure 3 is a torque waveform diagram of a finite element simulation of a secondary rotor assembly in an embodiment of the utility model;

[0037] like Figure 3 As shown in the torque waveform diagram of the finite element simulation of the auxiliary rotor assembly 20, the total torque generated by the two auxiliary rotor assemblies 20 has a torque order of 12, a maximum torque of 12.04 Nm, and a minimum torque of -11.38 Nm.

[0038] Figure 4 It is a torque waveform diagram of the finite element simulation of the stacked rotor structure of the permanent magnet synchronous motor in the embodiment of the utility model.

[0039] like Figure 4 As shown in the torque waveform diagram of the finite element simulation of the stacked rotor structure of the permanent magnet synchronous motor provided by the utility model, the average torque is 179.95Nm, the maximum torque is 184.41Nm, the minimum torque is 174.06Nm, and the torque ripple is 5.75%; Figure 2Compared with the torque waveform diagram simulated by the main rotor, the average torque remains basically unchanged, but the torque pulsation decreases significantly, and the torque output stability is significantly improved. Therefore, the generator provided by the utility model can reduce the torque pulsation of the output torque without reducing the output torque through the permanent magnet synchronous motor stacked rotor structure provided by the utility model, improve the output torque quality of the motor, and prolong the service life of the motor.

[0040] Functions and Effects of the Embodiments

[0041] The permanent magnet synchronous motor stacked rotor structure provided by the utility model comprises a main rotor assembly and a sub-rotor assembly, the main rotor assembly comprises a main rotor body and a main rotor permanent magnet, the main rotor permanent magnet is embedded in the main rotor body to form a built-in permanent magnet synchronous motor rotor structure, the magnetic resistance torque is caused by the motor salient pole effect, and the motor torque density is improved, the sub-rotor assembly is arranged on both sides of the main rotor body, comprises a sub-rotor body and a sub-rotor permanent magnet, the sub-rotor permanent magnet is arranged on the sub-rotor body, the sub-rotor assembly forms a surface-mounted permanent magnet synchronous motor rotor structure, can effectively reduce permanent magnet leakage, generate harmonic torque with an average torque of zero, and is used to offset the torque pulsation generated by the main rotor assembly, the permanent magnet synchronous motor stacked rotor structure provided by the utility model can reduce the torque pulsation of the output torque without reducing the output torque, improve the output torque quality of the motor, and extend the service life of the motor.

[0042] The above is an exemplary description of the utility model in conjunction with the accompanying drawings. Obviously, the specific implementation of the utility model is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the method concept and technical solution of the utility model; or the above concept and technical solution of the utility model are directly applied to other occasions without improvement, they are all within the protection scope of the utility model.

Claims

1. A permanent magnet synchronous motor stacked rotor structure, characterized in that: include: A main rotor assembly (10) comprises a main rotor body (11) and a main rotor permanent magnet (12), wherein the main rotor permanent magnet (12) is embedded in the main rotor body (11); The auxiliary rotor assembly (20) is arranged on both sides of the main rotor body (11), and comprises an auxiliary rotor body (21) and an auxiliary rotor permanent magnet (22), wherein the auxiliary rotor permanent magnet (22) is arranged on the auxiliary rotor body (21).

2. The permanent magnet synchronous motor stacked rotor structure according to claim 1, characterized in that: The main rotor body (11) is cylindrical and is provided with a main rotor shaft hole (13).

3. The permanent magnet synchronous motor stacked rotor structure according to claim 2, characterized in that: The auxiliary rotor body (21) is in the shape of a disk and is provided with an auxiliary rotor shaft hole (23).

4. The permanent magnet synchronous motor stacked rotor structure according to claim 3, characterized in that: The main rotor body (11) and the auxiliary rotor body (21) have the same diameter, and the main rotor shaft hole (13) and the auxiliary rotor shaft hole (23) have the same aperture.

5. The permanent magnet synchronous motor stacked rotor structure according to claim 4, characterized in that: The auxiliary rotor permanent magnets (22) are evenly distributed on the auxiliary rotor body (21), and the number and polarity of the auxiliary rotor permanent magnets (22) match the amplitude and order of the torque pulsation generated by the main rotor assembly (10).

6. The permanent magnet synchronous motor stacked rotor structure according to claim 5, characterized in that: The ratio of the length of the core of the auxiliary rotor assembly (20) to the length of the core of the main rotor assembly (10) is in the range of 5% to 10%.

7. The permanent magnet synchronous motor stacked rotor structure according to claim 5, characterized in that: The installation angle between the main rotor body (11) and the auxiliary rotor body (21) matches the phase of the torque pulsation generated by the main rotor assembly (10).

8. The permanent magnet synchronous motor stacked rotor structure according to claim 1, characterized in that: The main rotor body (11) and the auxiliary rotor body (21) are both formed by laminating silicon steel sheets.

9. The permanent magnet synchronous motor stacked rotor structure according to claim 1, characterized in that: The auxiliary rotor permanent magnet (22) is a neodymium iron boron permanent magnet.

10. A permanent magnet synchronous motor, characterized in that: A permanent magnet synchronous motor stacked rotor structure comprising any one of claims 1 to 9.

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