Permanent magnet motor

Abstract

The present application discloses a permanent magnet motor, which includes a housing, a stator and a rotor; the stator includes a stator tooth portion, a winding coil and a stator yoke portion; the stator tooth portion is annular and made of amorphous alloy, and a plurality of winding slots and a plurality of first clamping slots are formed in the stator tooth portion, and the winding coil is installed in the winding slots; the stator yoke portion is annular and made of amorphous alloy, and the stator yoke portion is sleeved on the stator tooth portion so that the inner diameter surface of the stator yoke portion covers and closes the opening of the winding slot; a plurality of second clamping slots are formed in the stator yoke portion, and each second clamping slot and the corresponding first clamping slot cooperate to form a fixing slot. A fixing member is located in the fixing slot, and the outer contour of the fixing member is consistent with the inner contour of the fixing slot, so that the fixing member can fix the stator yoke portion and the stator tooth portion and make the stator yoke portion and the stator tooth portion relatively fixed. Through the above arrangement, the vibration noise of the permanent magnet motor can be reduced and the material utilization rate can be improved.

Description

Technical Field

[0001] This application relates to the technical field of motors, and in particular, to a permanent magnet motor. Background Art

[0002] Permanent magnet motors generally include a stator, a rotor, and winding coils. In the prior art, a stator made of amorphous alloy materials such as iron-based amorphous alloys has higher magnetic permeability, lower coercivity, higher resistivity, and lower energy loss compared to a stator made of traditional silicon steel materials. Therefore, a stator made of amorphous alloy materials can reduce the stator loss of the motor, improve the energy utilization rate of the motor, and reduce the heat generation of the motor, so that the motor can output higher power.

[0003] Iron core teeth for winding the winding coils are usually provided on the stator. However, in the prior art, the iron core teeth are usually of an open slot structure, and the open slot structure will cause uneven distribution of the air gap in the motor, resulting in uneven distribution of the magnetic field in the air gap, further leading to increased electromagnetic force pulsation, increased torque pulsation of the rotor, and then causing the rotor vibration to collide with the motor housing, resulting in noise generated by the motor.

[0004] Secondly, the iron core teeth of the open slot structure will cause the winding coils to fall off. Therefore, structures such as tooth tips are usually provided on the iron core teeth to prevent the winding coils from falling off the iron core teeth. However, the shapes of tooth tips and the like in the prior art are complex, and the properties of amorphous alloy materials are brittle. Therefore, when processing complex shapes such as tooth tips with amorphous alloy materials, the amorphous alloy materials will break, resulting in a reduction in the utilization rate of the amorphous alloy materials.

[0005] Therefore, on the premise of using amorphous alloy materials to make permanent magnet motors to improve the output power of permanent magnet motors, how to reduce the vibration noise of the motor and improve the material utilization rate of the motor is a technical problem that those skilled in the art urgently need to solve. Summary of the Invention

[0006] To solve the deficiencies of the prior art, the purpose of this application is to provide a permanent magnet motor, which can reduce the vibration noise of the permanent magnet motor and improve the material utilization rate of the permanent magnet motor.

[0007] To achieve the above purpose, the following technical solutions are adopted in this application:

[0008] A permanent magnet motor, which includes a housing, a stator, and a rotor. The stator is fixed within the housing, the rotor is surrounded by the stator teeth, and the rotor is rotatably connected to the housing so that the rotor can rotate relative to the stator. The stator includes stator teeth, winding coils, and a stator yoke. The stator teeth are annular and made of amorphous alloy. The stator teeth are provided with a plurality of winding slots and a plurality of first clamping slots. The openings of the winding slots and the openings of the first clamping slots are both located on the outer diameter surface of the stator teeth. One first clamping slot is provided between adjacent two winding slots, and one winding slot is provided between adjacent two first clamping slots. The winding coils are installed in the winding slots. The stator yoke is annular and made of amorphous alloy. The stator yoke is sleeved on the stator teeth so that the inner diameter surface of the stator yoke covers and closes the openings of the winding slots. The stator yoke is provided with a plurality of second clamping slots. The openings of the second clamping slots are located on the inner diameter surface of the stator yoke. The opening of each second clamping slot corresponds to one first clamping slot, and each second clamping slot and the corresponding first clamping slot cooperate to form a fixing slot. A fixing member is located in the fixing slot, and the outer contour of the fixing member is consistent with the inner contour of the fixing slot so that the fixing member can fix the stator yoke and the stator teeth and make the stator yoke and the stator teeth relatively fixed. The rotor is surrounded by the stator and is rotatably connected to the housing so that the rotor can rotate relative to the stator.

[0009] Further, define a cross-sectional plane perpendicular to the axial direction of the stator teeth. The cross-section of the fixing slot intercepted by the cross-sectional plane is a fixing cross-section. The fixing cross-section is one of a triangle, a quadrilateral, a pentagon... an n-sided polygon, where n is an integer greater than 3; or the fixing cross-section is a shape formed by surrounding at least one curve and at least one straight line; or the fixing cross-section is a shape formed by surrounding at least one curve.

[0010] Further, the bottom of the winding slot extends along a preset plane perpendicular to the radial direction of the stator teeth. The minimum distance between the preset plane and the axis of the stator teeth is the slot pitch. The ratio range of the inner circle radius of the stator teeth to the slot pitch is from 0.78 to 0.99.

[0011] Further, a plurality of winding slots and a plurality of first clamping slots penetrate the stator teeth along the axial direction of the stator teeth, and a plurality of second clamping slots penetrate the stator yoke along the axial direction of the stator yoke.

[0012] Further, the stator further includes a stator outer shell and two end covers. The stator outer shell is annular. The stator outer shell is sleeved on the stator yoke and is in interference fit with the stator yoke. The two end covers are respectively located at both ends of the stator outer shell along the axial direction of the stator outer shell, and the end covers are fixedly connected to the stator outer shell.

[0013] Further, a plurality of first mounting holes are provided in the stator housing along its circumferential direction. The plurality of first mounting holes penetrate through the stator housing along the axial direction of the stator housing. A plurality of second mounting holes are provided in each end cover and are in cooperation with the first mounting holes. The plurality of second mounting holes penetrate through the end cover along the axial direction of the stator housing. The stator further includes a plurality of fasteners. Each fastener passes through a second mounting hole in one of the end covers, a corresponding first mounting hole in the stator housing, and a corresponding second mounting hole in the other end cover, so that the two end covers and the stator housing are fixedly connected. The stator housing is made of aluminum alloy, and the fasteners are bolts made of steel material.

[0014] Further, the outer diameter of the stator tooth portion is substantially the same as the inner diameter of the stator yoke portion.

[0015] Further, the rotor includes a first rotating shaft, a second rotating shaft, a permanent magnet, a first sheath, and a second sheath. An installation groove is provided in the first rotating shaft, and an annular groove is provided in the first rotating shaft. The opening of the annular groove is located on the outer surface of the first rotating shaft. The second rotating shaft is at least partially located in the installation groove and is fixed to the installation groove; a plurality of permanent magnets are provided. The plurality of permanent magnets are in a fan-shaped ring shape, and the plurality of permanent magnets are distributed in the annular groove along the circumferential direction of the first rotating shaft. The first sheath is wound around the plurality of permanent magnets. The second sheath is sleeved on the first sheath and is in interference fit with the first sheath. The first sheath is made of amorphous alloy; the second sheath is made of carbon fiber material.

[0016] Further, the length of the annular groove along the axial direction of the first rotating shaft is the same as that of the permanent magnet. The lengths of the first sheath and the second sheath along the axial direction of the first rotating shaft are greater than the length of the annular groove along the axial direction of the first rotating shaft.

[0017] Further, a plurality of weight reduction grooves are provided in the second rotating shaft. The plurality of weight reduction grooves are evenly distributed on the outer diameter surface of the second rotating shaft along the circumferential direction of the second rotating shaft, and the openings of the plurality of weight reduction grooves face the first rotating shaft.

[0018] Further, the two ends of the first rotating shaft along its axial direction are defined as a first section and a second section respectively. The length of the first section along the axial direction of the first rotating shaft is the same as that of the second section along the axial direction of the first rotating shaft; the volume of the first section is greater than the volume of the second section, or an extension member for increasing the volume of the first section is provided on the first section. The extension member is fixed to the first section or is integrally formed with the first section.

[0019] The winding slots of the permanent magnet motor described above can cooperate with the stator yoke portion to form a closed slot structure, which is beneficial to make the magnetic field distribution in the air gap more uniform, so as to reduce the electromagnetic force pulsation, and further reduce the torque pulsation of the rotor, and then reduce the vibration and noise generated during the operation of the permanent magnet motor. Moreover, there is no need to machine complex shapes such as tooth tips for avoiding the winding coil from falling off, so as to avoid damaging the amorphous alloy material due to machining complex shapes such as tooth tips, which is beneficial to improving the material utilization rate of the permanent magnet motor. Description of the Drawings

[0020] Figure 1 Explosion schematic diagram of the overall structure of the permanent magnet motor provided by the embodiment of the present application;

[0021] Figure 2 Structural schematic diagram of the stator of the permanent magnet motor provided by the embodiment of the present application;

[0022] Figure 3 Schematic diagram of the change in electromagnetic force density of the stator structure of the permanent magnet motor provided by the embodiment of the present application and the traditional stator structure;

[0023] Figure 4 Schematic diagram of the change in torque of the rotor of the permanent magnet motor provided by the embodiment of the present application and the rotor of the traditional stator structure;

[0024] Figure 5 ERP level waterfall diagram of the permanent magnet motor provided by the embodiment of the present application;

[0025] Figure 6 ERP level waterfall diagram of the motor with the traditional stator structure;

[0026] Figure 7 Schematic diagram of the change in A-weighted noise of the permanent magnet motor provided by the embodiment of the present application;

[0027] Figure 8 Schematic diagram of the change in A-weighted noise of the motor with the traditional stator structure;

[0028] Figure 9 Structural schematic diagram of the rotor of the permanent magnet motor provided by the embodiment of the present application;

[0029] Figure 10 Force analysis diagram of the second sheath of the permanent magnet motor provided by the embodiment of the present application;

[0030] Figure 11 Force analysis diagram of the carbon fiber sheath in the motor without adding the amorphous alloy sheath;

[0031] Figure 12 Structural schematic diagram of another perspective of the rotor of the permanent magnet motor provided by the embodiment of the present application. Detailed implementation manners

[0032] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the specific embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application.

[0033] It should be noted that the terms "first", "second" and similar terms used in the description and claims of this application do not denote any order, quantity or importance, but are only used to distinguish different components. Similarly, terms such as "a" or "an" do not denote a quantity limitation, but mean that there is at least one. "Plurality" or "several" means at least two. Unless otherwise indicated, terms such as "front", "rear", "left", "right", "lower" and / or "upper" are only for convenience of description and are not limited to a position or a spatial orientation. Terms such as "comprising" or "including" mean that the elements or items appearing before "comprising" or "including" cover the elements or items listed after "comprising" or "including" and their equivalents, and do not exclude other elements or items. Terms such as "connected" or "coupled" are not limited to physical or mechanical connections, and may include electrical connections, whether direct or indirect.

[0034] As used in the description and appended claims of this application, the singular forms "a", "the" and "said" are also intended to include the plural forms, unless the context clearly dictates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0035] As Figure 1 and Figure 2 As shown, this application provides a permanent magnet motor 100, which includes a housing 11, a stator 12 and a rotor 13. The housing 11 serves as the basic framework of the permanent magnet motor 100 and is used to support the stator 12 and the rotor 13. The stator 12 is fixed within the housing 11 and is used to generate a rotating magnetic field. The rotor 13 is surrounded by the stator 12, and the rotor 13 is rotatably connected to the housing 11 so that the rotor 13 can rotate relative to the stator 12, and the rotor 13 can cooperate with the rotating magnetic field to generate an electromagnetic torque.

[0036] Specifically, the stator 12 includes stator teeth 121, winding coils 122, a stator yoke 123 and a fixing member 124. Among them, both the stator teeth 121 and the stator yoke 123 are annular in shape and made of amorphous alloy, and the stator yoke 123 is sleeved on the stator teeth 121. Exemplarily, the rotor 13 is surrounded by the stator teeth 121. The fixing member 124 is used to fix the relative positions of the stator teeth 121 and the stator yoke 123 so that the stator teeth 121 and the stator yoke 123 can form a stator core. The winding coils 122 are used to cooperate with the stator core to generate a rotating magnetic field.

[0037] Through the above settings, the stator core can be divided into two independent components, namely the stator tooth part 121 and the stator yoke part 123. Therefore, the stator tooth part 121 and the stator yoke part 123 can be processed separately on two independent amorphous alloy materials, so as to avoid the stress of the amorphous alloy material being too concentrated when processing the entire stator core structure on one amorphous alloy material, and further avoid the amorphous alloy material being damaged due to excessive stress concentration, which is beneficial to improving the material utilization rate of the permanent magnet motor 100 and then reducing the production cost of the stator 12.

[0038] Moreover, by separately and independently arranging the stator core, that is, by forming the stator core with the stator tooth part 121 and the stator yoke part 123, the structural complexity of the stator tooth part 121 and the stator yoke part 123 can be simplified, and further the processing difficulty of the stator tooth part 121 and the stator yoke part 123 can be reduced. Secondly, it can also avoid the structure of the stator tooth part 121 and the stator yoke part 123 being too complex, resulting in excessive mechanical stress being applied during the processing of the amorphous alloy material, thereby avoiding the stress on the amorphous alloy being excessive and reducing the magnetic permeability of the amorphous alloy, and further being beneficial to improving the magnetic permeability of the stator tooth part 121 and the stator yoke part 123, so as to improve the power of the permanent magnet motor 100.

[0039] In addition, since both the stator tooth part 121 and the stator yoke part 123 are annular in shape, and multiple annular structures with different sizes can be processed from the inside to the outside on one amorphous alloy material, so that multiple annular structures with different sizes can be processed into stator tooth parts 121 or stator yoke parts 123 with different sizes, which is beneficial to improving the material utilization rate of the amorphous alloy and further beneficial to reducing the production cost of the permanent magnet motor 100.

[0040] Exemplarily, both the stator tooth part 121 and the stator yoke part 123 are made of iron-based amorphous alloy. With such a setting, the iron-based amorphous alloy has a high magnetic permeability and resistivity, as well as a low coercive force and energy loss, which is beneficial to reducing the heat generation of the stator 12 and further beneficial to improving the output power of the permanent magnet motor 100. It should be noted that the amorphous alloy is not limited to the iron-based amorphous alloy, as long as the amorphous alloy can meet the working requirements of the stator 12.

[0041] In this embodiment, the stator tooth part 121 is provided with a plurality of winding slots 1211. The plurality of winding slots 1211 are uniformly arranged along the circumferential direction of the stator tooth part 121. The openings of the winding slots 1211 are located on the outer diameter surface of the stator tooth part 121, and the winding coils 122 are installed in the winding slots 1211. Among them, the outer diameter surface refers to the surface formed by the outer wall of the stator tooth part 121 surrounding along the circumferential direction of the stator tooth part 121.

[0042] Specifically, the stator yoke 123 is sleeved on the stator tooth part 121, and the inner diameter surface of the stator yoke 123 covers and closes the opening of the winding slot 1211. Herein, the inner diameter surface refers to the surface formed by the inner wall of the stator yoke 123 surrounding along the circumferential direction of the stator yoke 123. With such a setting, the winding slot 1211 can cooperate with the inner diameter surface of the stator yoke 123 to form a closed slot structure. Through the structure of the closed slot, the winding coil 122 can be prevented from falling off from the winding slot 1211. Therefore, there is no need to process complex structures such as tooth tips on the winding slot 1211 for preventing the winding coil 122 from falling off, which is beneficial to reducing the structural complexity of the stator 12, avoiding local stress concentration and embrittlement of the machining edge of the stator tooth part 121 due to processing complex structures such as tooth tips on the stator tooth part 121, and further avoiding the fracture of the stator tooth part 121, thereby increasing the cost of the amorphous alloy material, being beneficial to improving the material utilization rate, and then reducing the production cost of the permanent magnet motor 100. Moreover, the need to process complex structures such as tooth tips is also beneficial to reducing the machining difficulty of the stator tooth part 121, simplifying the machining process of the stator 12, being beneficial to improving the machining efficiency of the stator 12, and being beneficial to realizing the large-scale automated production of the stator 12, and further being beneficial to improving the overall production efficiency of the permanent magnet motor 100.

[0043] Secondly, the setting of the closed slot can avoid the distortion of the air gap structure caused by setting an open slot structure, so that the overall structure of the air gap in the permanent magnet motor 100 is smoother, and the magnetic field distribution in the air gap is more uniform. Therefore, the distortion of the magnetic field distribution in the air gap caused by the distortion of the air gap structure to generate air gap harmonics can be avoided, and further the aggravation of the electromagnetic force pulsation caused by the generation of air gap harmonics can be avoided, being beneficial to reducing the torque pulsation of the rotor 13 caused by the electromagnetic force pulsation, and then being beneficial to reducing the motor vibration caused by the torque pulsation, and being beneficial to reducing the noise generated during the operation of the permanent magnet motor 100. Moreover, by reducing the torque pulsation of the rotor 13, it is also beneficial to avoid excessive collision between the rotor 13 and the housing 11, being beneficial to improving the operation stability of the rotor 13, being beneficial to improving the service life of the rotor 13, and further being beneficial to improving the service life of the permanent magnet motor 100.

[0044] In addition, the setting of the closed slot can improve the supporting force between the stator yoke 123 and the winding slot 1211, being beneficial to improving the overall strength of the stator 12, and further being able to improve the structural strength of the stator tooth part 121. With such a setting, the deformation of the stator tooth part 121 caused by the insufficient strength of the stator tooth part 121 under the action of external force and electromagnetic force can be avoided, so as to avoid the deformation of the air gap and the distortion of the magnetic field in the air gap, and further being beneficial to reducing the electromagnetic force pulsation, reducing the torque pulsation of the rotor 13, and then being beneficial to reducing the vibration noise of the permanent magnet motor 100.

[0045] It should be noted that the air gap refers to the space between the stator 12 and the rotor 13, and the air gap harmonic refers to the spatial harmonic caused by the magnetic field distortion in the air gap.

[0046] In this embodiment, the stator tooth portion 121 is provided with a first clamping groove 1212, and the stator yoke portion 123 is provided with a second clamping groove 1231. Both the first clamping groove 1212 and the second clamping groove 1231 are provided with a plurality of them, and the first clamping groove 1212 is uniformly arranged along the circumferential direction of the stator tooth portion 121, and the second clamping groove 1231 is uniformly arranged along the circumferential direction of the stator yoke portion 123. Specifically, the openings of the first clamping groove 1212 are all located on the outer diameter surface of the stator tooth portion 121, and the openings of the second clamping groove 1231 are located on the inner diameter surface of the stator yoke portion 123. And when the stator yoke portion 123 is sleeved on the stator tooth portion 121, the opening of each second clamping groove 1231 corresponds to a first clamping groove 1212, so that each second clamping groove 1231 and the corresponding first clamping groove 1212 cooperate to form a fixing groove 125.

[0047] More specifically, the fixing member 124 is located in the fixing groove 125, and the outer contour of the fixing member 124 is consistent with the inner contour of the fixing groove 125, so that the fixing member 124 can fix the stator yoke portion 123 and the stator tooth portion 121, and make the stator yoke portion 123 and the stator tooth portion 121 relatively fixed. With such a setting, through the cooperation of the fixing member 124 and the fixing groove 125, the relative fixing of the stator tooth portion 121 and the stator yoke portion 123 can be realized, so as to limit the stator tooth portion 121 and the stator yoke portion 123 in the circumferential direction, so that the two independent stator tooth portions 121 and stator yoke portions 123 form a stator core, and thus the assembly process of the stator 12 can be simplified.

[0048] In some embodiments, the fixing member 124 is a carbon fiber rod. The carbon fiber rod has high structural strength, which is beneficial to improving the connection stability between the stator tooth portion 121 and the stator yoke portion 123. And the carbon fiber rod is basically non-conductive and non-magnetic, so that eddy current loss can be avoided on the fixing member 124, which is beneficial to improving the service life of the stator 12 and the operating efficiency of the permanent magnet motor 100.

[0049] In this embodiment, there is a first clamping groove 1212 between two adjacent winding grooves 1211, and there is a winding groove 1211 between two adjacent first clamping grooves 1212. With such a setting, the first clamping groove 1212 and the winding groove 1211 can be arranged at intervals on the stator tooth portion 121, and the fixing member 124 is assembled through the cooperation of the first clamping groove 1212 and the second clamping groove 1231, which is beneficial to improving the connection stability between the stator tooth portion 121 and the stator yoke portion 123, and thus beneficial to improving the structural stability of the stator 12.

[0050] It should be noted that in the present application, the outer diameter surface of the stator tooth portion 121 and the inner diameter surface of the stator yoke portion 123 are in clearance fit, which is beneficial to improving the disassembly and assembly convenience of the stator tooth portion 121 and the stator yoke portion 123.

[0051] As Figure 3 shown, as an implementation manner, the change in the electromagnetic force density in the air gap is calculated within the range of the air gap outer diameter circumference of 0 - 500 mm. Among them, the abscissa is the distance of the air gap outer diameter circumference, and the ordinate is the electromagnetic force density in the air gap. It can be seen that within the range of the air gap outer diameter circumference of 0 - 500 mm, the waveform change degree of the electromagnetic force density of the stator 12 of the present application is less than that of the traditional stator structure, that is, the electromagnetic force pulsation of the stator 12 of the present application is less than that of the traditional stator structure. Among them, the stator 12 of the present application is the stator 12 with a closed slot structure of the present application, and the traditional stator structure is the stator structure with an open slot structure. It can be understood that the electromagnetic force pulsation can be effectively reduced by the stator 12 with a closed slot structure of the present application.

[0052] It should be noted that Figure 3 the red waveform line in

[0053] As Figure 4 shown, as an implementation manner, the torque of the motor rotor is calculated during the operation of the motor. Among them, the abscissa is the motor operation time, and the ordinate is the torque of the motor rotor. It can be seen that within 0 - 4 ms of the motor operation, the waveform change degree of the torque of the rotor 13 of the permanent magnet motor 100 of the present application is less than that of the rotor of the traditional motor, that is, the torque pulsation of the rotor 13 of the permanent magnet motor 100 of the present application is less than that of the rotor of the traditional motor. It can be understood that the torque pulsation of the rotor 13 can be effectively reduced by the stator 12 with a closed slot structure of the present application.

[0054] It should be noted that Figure 4 the red waveform line is the waveform line of the torque of the rotor 13 of the permanent magnet motor 100 of the present application, and the black waveform line is the waveform line of the torque of the rotor of the traditional motor.

[0055] As Figure 5 and Figure 6 shown, as an implementation manner, Figure 5The permanent magnet motor 100 of the present application uses simulation software to calculate the waterfall diagram of the ERP (Equivalent Radiated Power) level of the motor. Among them, the abscissa frequency (Hz) is the sound frequency generated during the operation of the permanent magnet motor 100, the ordinate speed (r / min) is the speed of the permanent magnet motor 100, and different color areas represent the far-field sound power level [dB]. The larger the far-field sound power level, the greater the noise decibel generated by the permanent magnet motor 100; Figure 6 It is a waterfall diagram of the ERP (Equivalent Radiated Power) level of a motor with a traditional stator structure calculated by simulation software. Among them, the abscissa frequency (Hz) is the sound frequency generated during the operation of the motor with a traditional stator structure, the ordinate speed (r / min) is the speed of the motor with a traditional stator structure, and different color areas represent the equivalent radiated power level [dB]. The larger the equivalent radiated power level, the greater the noise decibel generated by the motor with a traditional stator structure. In the range where the motor speed is 1000 - 8000 r / min and the sound frequency generated during the operation of the motor is the same, the noise generated by the permanent magnet motor 100 of the present application is less than that generated by the motor with a traditional stator structure. It can be understood that the stator 12 with a closed slot structure in the present application can effectively reduce the noise generated by the motor.

[0056] As Figure 7 and Figure 8 shown, as an implementation manner, a measurement point is set at a distance of 30 cm from the center of the motor, and the A-weighted noise level at a motor speed of 5000 r / min is calculated. Among them, Figure 7 is a schematic diagram of the change in the A-weighted noise of the permanent magnet motor 100 of the present application, Figure 8 is a schematic diagram of the change in the A-weighted noise of a motor with a traditional stator structure. The abscissa frequency (Hz) is the sound frequency generated during the operation of the motor, and the ordinate actual (dBA) is the A-weighted actual sound pressure level value. It can be seen that in the range of 416.67 Hz - 6250 Hz, the noise generated by the permanent magnet motor 100 of the present application at a speed of 5000 r / min is less than that generated by the motor with a stator structure having an open slot. It should be noted that the A-weighted noise level is the A sound level measured by a sound level meter or an equivalent measuring instrument through the A-weighted network.

[0057] As Figure 2As shown, as an implementation, a cross-sectional plane 101 perpendicular to the axial direction of the stator tooth portion 121 is defined, and the cross-section of the fixing groove 125 intercepted by the cross-sectional plane 101 is a fixing cross-section. Specifically, the fixing cross-section is one of a triangle, a quadrilateral, a pentagon... an n-sided polygon, where n is an integer greater than 3. By setting it in this way, the fixing cross-section can be polygonal. Exemplarily, the fixing cross-section can be in polygonal shapes such as a triangle or a rectangle. The polygonal shape can restrict the movement of the fixing member 124 in the fixing groove 125, so that the fixing member 124 can fix the relative positions of the stator tooth portion 121 and the stator yoke portion 123.

[0058] Alternatively, the fixing cross-section is a shape formed by surrounding at least one curve and at least one straight line. Exemplarily, the fixing cross-section is semi-circular. By setting it in this way, the fixing member 124 can fix the relative positions of the stator tooth portion 121 and the stator yoke portion 123 through the semi-circular fixing cross-section.

[0059] Alternatively, the fixing cross-section is a shape formed by surrounding at least one curve. Exemplarily, the fixing cross-section is circular. By setting it in this way, the fixing member 124 can fix the relative positions of the stator tooth portion 121 and the stator yoke portion 123 through the circular fixing cross-section.

[0060] It should be noted that the fixing cross-section of the present application is circular. It can be understood that the circular shape is simple, which is beneficial to simplifying the processing techniques of the first clamping groove 1212, the second clamping groove 1231, and the fixing member 124, and thus is beneficial to improving the processing efficiency of the stator 12.

[0061] As an implementation manner, the bottom of the winding slot 1211 extends along a preset plane 102 perpendicular to the radial direction of the stator tooth portion 121. The minimum distance between the preset plane 102 and the axis of the stator tooth portion 121 is defined as the slot pitch D. Wherein, the ratio range of the inner circle radius R of the stator tooth portion 121 to the slot pitch D is 0.78 to 0.99. Specifically, the ratio of the inner circle radius R of the stator tooth portion 121 to the slot pitch D is 0.986. With such a setting, it can be avoided that the ratio of the inner circle radius R of the stator tooth portion 121 to the slot pitch D is too large, resulting in too thin a thickness of the bottom of the winding slot 1211 along the radial direction of the stator tooth portion 121, so as to avoid too thin a thickness of the stator tooth portion 121 and reduce the structural strength of the stator tooth portion 121. Thus, the volume of the winding slot 1211 can be increased on the premise of meeting the structural strength requirements of the stator tooth portion 121, which is beneficial to arranging more winding coils 122 in the winding slot 1211. In addition, it can also be avoided that the ratio of the inner circle radius R of the stator tooth portion 121 to the slot pitch D is too small, resulting in too thick a thickness of the bottom of the winding slot 1211 along the radial direction of the stator tooth portion 121, thereby avoiding that some magnetic induction lines generated by the winding coil 122 cannot pass through the too thick bottom of the slot, resulting in the magnetic induction lines not being able to be closed, and further avoiding the generation of magnetic leakage due to the non-closure of the magnetic induction lines, which is beneficial to reducing the energy loss of the permanent magnet motor 100, and then beneficial to improving the operating power of the permanent magnet motor 100.

[0062] As an implementation manner, a plurality of winding slots 1211 are arranged axially through the stator tooth portion 121 along the stator tooth portion 121. With such a setting, the winding coil 122 can penetrate through the stator 12, thus avoiding the existence of a dead angle of the rotating magnetic field inside the stator 12 caused by the winding coil 122 not penetrating through the stator 12. Furthermore, it is beneficial to improve the filling degree of the rotating magnetic field in the stator 12, which is beneficial to improving the operating power of the permanent magnet motor 100.

[0063] In this implementation manner, a plurality of first clamping slots 1212 are arranged axially through the stator tooth portion 121 along the stator tooth portion 121. And, a plurality of second clamping slots 1231 are arranged axially through the stator yoke portion 123 along the stator yoke portion 123. With such a setting, along the axial direction of the stator tooth portion 121, the fixing member 124 can penetrate through the stator tooth portion 121 and the stator yoke portion 123, thus avoiding the existence of a supporting dead angle of the fixing member 124 inside the stator 12 caused by the fixing member 124 not completely penetrating through the stator tooth portion 121 and the stator yoke portion 123, and avoiding the relative deflection of the stator tooth portion 121 and the stator yoke portion 123 caused by the existence of a supporting dead angle between the stator tooth portion 121 and the stator yoke portion 123. Furthermore, it is beneficial to improve the connection stability between the stator tooth portion 121 and the stator yoke portion 123.

[0064] As an implementation manner, the stator 12 further includes a stator housing 126 and two end covers 127. Specifically, the stator housing 126 is in a ring shape, and the stator housing 126 is sleeved on the stator yoke portion 123 and is in interference fit with the stator yoke portion 123. More specifically, the two end covers 127 are respectively located at two axial ends of the stator housing 126 along the axis of the stator housing 126, and the end covers 127 are fixedly connected to the stator housing 126. With such a setting, the stator housing 126 and the end covers 127 can protect the internal stator tooth portion 121, stator yoke portion 123 and winding coils 122, thereby being beneficial to improving the use safety of the permanent magnet motor 100.

[0065] As an alternative implementation manner, a plurality of first mounting holes 1261 are formed in the stator housing 126 along its circumferential direction, and the plurality of first mounting holes 1261 penetrate through the stator housing 126 along the axis of the stator housing 126. Moreover, a plurality of second mounting holes 1271 that cooperate with the first mounting holes 1261 are formed in each end cover 127, and the plurality of second mounting holes 1271 penetrate through the end cover 127 along the axis of the stator housing 126.

[0066] Specifically, the stator 12 further includes fasteners (not shown in the figure), and there are a plurality of fasteners. Each fastener passes through a second mounting hole 1271 on one of the end covers 127, a corresponding first mounting hole 1261 on the stator housing 126, and a corresponding second mounting hole 1271 on the other end cover 127, so that the two end covers 127 and the stator housing 126 are fixedly connected. With such a setting, the stator housing 126 and the two end covers 127 can be fixed by the fasteners cooperating with the first mounting holes 1261 and the second mounting holes 1271, thereby being able to support the stator tooth portion 121, stator yoke portion 123 and winding coils 122. There is no need to use other fasteners to fix the above components, which is beneficial to reducing the number of fasteners used and further reducing the production cost of the permanent magnet motor 100. Moreover, it is also beneficial to improving the assembly efficiency of the permanent magnet motor 100.

[0067] In this implementation manner, the stator housing 126 is made of aluminum alloy. With such a setting, the aluminum alloy material has a relatively light weight. Therefore, on the premise of meeting the structural strength of the stator housing 126, the weight of the stator housing 126 can be reduced to make the stator 12 more lightweight. In addition, the fasteners are bolts made of steel material. With such a setting, by passing the bolts through the first mounting holes 1261 and the second mounting holes 1271 and tightening the bolts, the stator housing 126 and the two end covers 127 can be fixedly connected, which is beneficial to improving the assembly convenience of the stator housing 126 and the end covers 127. Moreover, the bolts made of steel material are industrial standard parts, so there is no need to customize the fasteners separately, which is beneficial to simplifying the processing technology of the permanent magnet motor 100.

[0068] It should be noted that the stator housing 126 can also be made of materials such as ductile iron and gray iron, and the application does not limit the material of the stator housing 126.

[0069] It should be noted that the fastener can also be a structure such as a screw or a rivet. The application does not limit the structural form of the fastener, and only needs to satisfy that it can fix the stator housing 126 and the two end covers 127.

[0070] As an implementation manner, the outer diameter of the stator tooth portion 121 is substantially the same as the inner diameter of the stator yoke portion 123. With such a setting, the stator tooth portion 121 and the stator yoke portion 123 can be in clearance fit, which is beneficial to improving the assembly convenience of the stator tooth portion 121 and the stator yoke portion 123. Moreover, through the above setting, after the stator tooth portion 121 and the stator yoke portion 123 are assembled, the winding slot 1211 can cooperate with the inner diameter surface of the stator yoke portion 123 to form a closed slot structure, which is beneficial to reducing the vibration and noise of the permanent magnet motor 100 and improving the material utilization rate. In addition, through the above setting, the connection tightness between the stator tooth portion 121 and the stator yoke portion 123 can also be improved, which is beneficial to improving the support stability between the stator tooth portion 121 and the stator yoke portion 123, and further beneficial to improving the overall structural strength of the stator 12.

[0071] As Figure 9 shown, as an implementation manner, the rotor 13 includes a first rotating shaft 131, a second rotating shaft 132, a permanent magnet 133, a first sheath 134, and a second sheath 135. Among them, the first rotating shaft 131 and the second rotating shaft 132 are fixedly connected, and the first rotating shaft 131 and the second rotating shaft 132 are used to output torque. A plurality of permanent magnets 133 are provided. The plurality of permanent magnets 133 are in a fan-shaped ring shape, and the plurality of permanent magnets 133 are fixedly connected to the first rotating shaft 131. The permanent magnets 133 are used to generate a magnetic field so that the magnetic field can cooperate with the rotating magnetic field generated by the stator 12 to drive the first rotating shaft 131 and the second rotating shaft 132 to rotate. The first sheath 134 is wound around the plurality of permanent magnets 133, and the second sheath 135 is sleeved on the first sheath 134 and is in interference fit with the first sheath 134. With such a setting, the first sheath 134 and the second sheath 135 can provide a pre-tightening force towards the first rotating shaft 131 for the permanent magnets 133, so as to prevent the permanent magnets 133 from detaching from the first rotating shaft 131 due to the action of centrifugal force during the rotation of the first rotating shaft 131, which is beneficial to improving the connection stability between the permanent magnets 133 and the first rotating shaft 131.

[0072] Specifically, the first sheath 134 is made of amorphous alloy. With such a setting, the amorphous alloy has a relatively high magnetic permeability, so that the first sheath 134 surrounding the permanent magnet 133 can form a pole shoe layer, and further makes the magnetic field distribution generated by the permanent magnet 133 more uniform, which is beneficial to improving the operating power of the permanent magnet motor 100. Secondly, the amorphous alloy material has the characteristics of high saturation magnetic induction intensity and low energy loss, so that the first sheath 134 can centrally bear the induced eddy current caused by the armature reaction in the permanent magnet motor 100, so as to prevent the permanent magnet 133 from bearing the induced eddy current and causing the temperature of the permanent magnet 133 to be too high. Furthermore, it can prevent the permanent magnet 133 from losing magnetism due to excessive temperature, which is beneficial to improving the service life of the permanent magnet 133.

[0073] It should be noted that during the energized operation of the motor, armature reaction will occur, resulting in magnetic field distortion in the motor, and further causing induced eddy current to be formed in the components in the motor, so that the components generate energy loss and heat. In this application, since the amorphous alloy has a higher saturation magnetic induction intensity than the permanent magnet 133, the induced eddy current formed by the armature reaction in the permanent magnet motor 100 can be concentrated on the first sheath 134. Moreover, the amorphous alloy has lower energy loss than the permanent magnet 133, so it can avoid excessive energy loss and heat generation of the induced eddy current on the first sheath 134, which is beneficial to reducing the heat generated during the operation of the permanent magnet motor 100, and further reducing the heat dissipation pressure of the permanent magnet motor 100, so as to improve the operating power of the permanent magnet motor 100.

[0074] More specifically, the second sheath 135 is made of carbon fiber material. With such a setting, the carbon fiber material has relatively high structural strength, which is beneficial to improving the overall structural strength of the rotor 13. Secondly, the carbon fiber material has the characteristics of basically non-magnetic and non-conductive, so it can avoid eddy current loss generated on the second sheath 135 due to conduction and magnetism, which is beneficial to improving the operating performance of the permanent magnet motor 100.

[0075] In this application, by arranging the first sheath 134 between the second sheath 135 and the permanent magnet 133, the shear force generated by the rotation of the first rotating shaft 131 borne by the second sheath 135 can be reduced, so as to prevent the second sheath 135 from falling off or breaking due to excessive shear force, which is beneficial to improving the installation stability of the second sheath 135 on the rotor 13.

[0076] As Figure 10 and Figure 11 shown, the force analysis diagram of the carbon fiber sheath is calculated at the same motor speed. Among them, Figure 10 This is the force analysis diagram of the second sheath 135 of the permanent magnet motor 100 of this application, Figure 11It is a stress analysis diagram of the carbon fiber sheath in the motor without the amorphous alloy sheath. It can be seen that the shear stress borne by the second sheath 135 of the permanent magnet motor 100 in this application (the maximum value is 101.27 MPa) is less than the shear stress borne by the carbon fiber sheath in the motor without the amorphous alloy sheath (the maximum value is 106.82 MPa). Moreover, the range where the shear stress borne by the second sheath 135 of the permanent magnet motor 100 in this application is greater than 100 MPa is smaller than the range where the shear stress borne by the carbon fiber sheath in the motor without the amorphous alloy sheath is greater than 100 MPa. It can be understood that the shear stress borne by the second sheath 135 of the permanent magnet motor 100 in this application is less than the shear stress borne by the carbon fiber sheath in the motor without the amorphous alloy sheath, so that the second sheath 135 in the permanent magnet motor 100 of this application can withstand a higher motor speed, which is conducive to increasing the critical speed of the permanent magnet motor 100.

[0077] In addition, by providing the first sheath 134 and the second sheath 135, the air gap thickness in the permanent magnet motor 100 can be reduced, so as to weaken the air gap magnetic field in the permanent magnet motor 100, and then reduce the air gap harmonics generated by the air gap magnetic field, which is beneficial to reducing the energy loss caused by the air gap harmonics, and then beneficial to improving the operating performance of the permanent magnet motor 100.

[0078] In this embodiment, an installation groove 1311 is provided in the first rotating shaft 131, and at least a part of the second rotating shaft 132 is located in the installation groove 1311 and fixed to the installation groove 1311. With such a setting, by providing the installation groove 1311, the mass of the first rotating shaft 131 can be reduced, which is beneficial to reducing the overall moment of inertia of the rotor 13, and then beneficial to increasing the critical speed of the permanent magnet motor 100. Secondly, by fixing the second rotating shaft 132 in the installation groove 1311, the structural strength of the first rotating shaft 131 can be improved, which is beneficial to improving the overall structural strength of the rotor 13. Moreover, in this application, the second rotating shaft 132 is a hollow shaft, so that the weight of the second rotating shaft 132 can be reduced, so that under the premise of meeting the strength requirements, the overall weight of the rotor 13 can be reduced, which is beneficial to reducing the overall moment of inertia of the rotor 13 to further increase the critical speed of the permanent magnet motor 100.

[0079] In this embodiment, an annular groove 1312 is provided on the first rotating shaft 131, and the opening of the annular groove 1312 is located on the outer surface of the first rotating shaft 131. Further, a plurality of permanent magnets 133 are distributed in the annular groove 1312 along the circumferential direction of the first rotating shaft 131. With such a setting, the permanent magnets 133 can be limited by the annular groove 1312, which is beneficial to improving the installation stability of the permanent magnets 133 on the first rotating shaft 131.

[0080] As an alternative embodiment, the length of the annular groove 1312 along the axial direction of the first rotating shaft 131 is the same as that of the permanent magnet 133. With such a setting, the tightness of the installation of the permanent magnet 133 in the annular groove 1312 can be improved, so as to prevent the permanent magnet 133 from deflecting left and right in the annular groove 1312, thereby further improving the installation stability of the permanent magnet 133 on the first rotating shaft 131.

[0081] In this embodiment, the lengths of the first sheath 134 and the second sheath 135 along the axial direction of the first rotating shaft 131 are greater than the length of the annular groove 1312 along the axial direction of the first rotating shaft 131. With such a setting, the first sheath 134 and the second sheath 135 can completely cover the permanent magnet 133, so as to prevent the permanent magnet 133 from being exposed in the air gap, which may cause the permanent magnet 133 to demagnetize due to the magnetic field distortion in the air gap, thus being beneficial to improving the service life of the permanent magnet 133.

[0082] As Figure 12 shown, as an embodiment, the second rotating shaft 132 is provided with a plurality of weight-reducing grooves 1321. The plurality of weight-reducing grooves 1321 are evenly distributed on the outer diameter surface of the second rotating shaft 132 along the circumferential direction of the second rotating shaft 132, and the openings of the plurality of weight-reducing grooves 1321 face the first rotating shaft 131. With such a setting, the weight-reducing grooves 1321 can further reduce the weight of the second rotating shaft 132, thereby further reducing the moment of inertia of the entire rotor 13. Moreover, the setting of the weight-reducing grooves 1321 can reduce the weight of the second rotating shaft 132 on the premise of meeting the strength requirements of the second rotating shaft 132, so that the entire rotor 13 can reduce the moment of inertia of the entire rotor 13 on the premise of meeting the strength requirements, which is beneficial to improving the power density of the permanent magnet motor 100.

[0083] As Figure 9 shown, as an embodiment, the two ends of the first rotating shaft 131 along its axial direction are defined as a first section 1313 and a second section 1314 respectively. The length of the first section 1313 along the axial direction of the first rotating shaft 131 is the same as that of the second section 1314 along the axial direction of the first rotating shaft 131; the volume of the first section 1313 is greater than the volume of the second section 1314;

[0084] Alternatively, an extension piece for increasing the volume of the first section 1313 is provided on the first section 1313, and the extension piece is fixed to the first section 1313 or integrally formed with the first section 1313.

[0085] Through the above settings, the volume on the first rotating shaft 131 can be increased. Taking the two ends of the first rotating shaft 131 along its axial direction as the first section 1313 and the second section 1314 respectively as an example for illustration. Due to the volume difference between the first section 1313 and the second section 1314, the air gap thickness at the first section 1313 and the second section 1314 in the permanent magnet motor 100 can be changed, and further the flow diameter of the air in the air gap is changed. Therefore, when the rotor 13 rotates to drive the air flow in the air gap, the air flow rate in the air gap will be reduced due to the limitation of the change in the air gap flow diameter, resulting in a low vacuum state in the air gap. Furthermore, the contact amount between the rotor 13 and the air in the air gap can be reduced, which is beneficial to reducing the wear caused by the contact between the rotor 13 and the air during rotation, and reducing the noise caused by the contact between the rotor 13 and the air during rotation. Subsequently, it is beneficial to improve the service life of the rotor 13 and reduce the operating noise of the permanent magnet motor 100.

[0086] It should be understood that for those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of this application.

Claims

1. A permanent magnet motor, characterized in that: The permanent magnet motor comprises: case; A stator, the stator being fixed in the housing and comprising: A stator tooth portion, the stator tooth portion is in a ring shape and is made of an amorphous alloy, the stator tooth portion is provided with a plurality of winding slots and a plurality of first clamping slots, the openings of the winding slots and the openings of the first clamping slots are both located on the outer diameter surface of the stator tooth portion, one first clamping slot is provided between two adjacent winding slots, and one winding slot is provided between two adjacent first clamping slots; A winding coil, wherein the winding coil is installed in the winding slot; A stator yoke, which is in a ring shape and made of an amorphous alloy, is sleeved on the stator teeth so that the inner diameter surface of the stator yoke covers and closes the opening of the winding slot, and the stator yoke is provided with a plurality of second clamping grooves, the openings of the second clamping grooves are located on the inner diameter surface of the stator yoke, each opening of the second clamping groove corresponds to one of the first clamping grooves, and each of the second clamping grooves cooperates with the corresponding first clamping groove to form a fixing groove; A fixing member, the fixing member is located in the fixing groove, and the outer contour of the fixing member is consistent with the inner contour of the fixing groove, so that the fixing member can fix the stator yoke and the stator tooth portion, and make the stator yoke and the stator tooth portion relatively fixed; The rotor is surrounded by the stator and is rotatably connected to the housing so that the rotor can rotate relative to the stator.

2. The permanent magnet motor according to claim 1, characterized in that: A section plane perpendicular to the axial direction of the stator tooth portion is defined, and the section of the fixed slot cut by the section plane is the fixed section; The fixed cross section is one of a triangle, a quadrilateral, a pentagon, ... an n-gon, wherein n is an integer greater than 3; Or the fixed cross section is a shape formed by at least one curve and at least one straight line; Or the fixed cross section is a shape formed by at least one curve.

3. The permanent magnet motor according to claim 1, characterized in that: The bottom of the winding slot extends along a preset plane perpendicular to the radial direction of the stator tooth, the minimum distance between the preset plane and the axis of the stator tooth is the slot pitch, and the ratio of the inner circle radius of the stator tooth to the slot pitch ranges from 0.78 to 0.

99.

4. The permanent magnet motor according to claim 1, characterized in that: The plurality of winding slots and the plurality of first clamping slots are arranged along the axial direction of the stator tooth portion and penetrate the stator tooth portion; and the plurality of second clamping slots are arranged along the axial direction of the stator yoke portion and penetrate the stator yoke portion.

5. The permanent magnet motor according to claim 1, characterized in that: The stator also includes a stator housing and two end covers. The stator housing is in a ring shape. The stator housing is sleeved on the stator yoke and has an interference fit with the stator yoke. The two end covers are respectively located at two ends of the stator housing along the axial direction of the stator housing, and the end covers are fixedly connected to the stator housing.

6. The permanent magnet motor according to claim 5, characterized in that: The stator housing is provided with a plurality of first mounting holes along its circumference, and the plurality of first mounting holes penetrate the stator housing axially along the stator housing, and each end cover is provided with a plurality of second mounting holes matching with the first mounting holes, and the plurality of second mounting holes penetrate the end cover axially along the stator housing, and the stator further comprises a plurality of fasteners, each of the fasteners is passed through a second mounting hole on one of the end covers, a corresponding first mounting hole on the stator housing, and a corresponding second mounting hole on the other end cover, so that the two end covers are fixedly connected to the stator housing; The stator shell is made of aluminum alloy, and the fasteners are bolts made of steel.

7. The permanent magnet motor according to claim 1, characterized in that: The outer diameter of the stator teeth portion is substantially consistent with the inner diameter of the stator yoke portion.

8. The permanent magnet motor according to claim 1, characterized in that: The rotor comprises: A first rotating shaft, wherein a mounting groove is formed in the first rotating shaft, and an annular groove is formed on the first rotating shaft, wherein an opening of the annular groove is located on an outer surface of the first rotating shaft; a second rotating shaft, the second rotating shaft being at least partially located in the mounting groove and fixed to the mounting groove; A plurality of permanent magnets, wherein the plurality of permanent magnets are in a fan-shaped ring shape and are distributed in the annular groove along the circumference of the first rotating shaft; A first sheath, wherein the first sheath is wound around the plurality of permanent magnets; a second sheath, the second sheath being sleeved on the first sheath and having an interference fit with the first sheath; The first sheath is made of amorphous alloy; the second sheath is made of carbon fiber material.

9. The permanent magnet motor according to claim 8, characterized in that: The annular groove is consistent with the length of the permanent magnet along the axial direction of the first rotating shaft; The lengths of the first sleeve and the second sleeve along the axial direction of the first rotating shaft are greater than the length of the annular groove along the axial direction of the first rotating shaft.

10. The permanent magnet motor according to claim 8, characterized in that: The second rotating shaft is provided with a plurality of weight-reducing grooves, which are evenly distributed on the outer diameter surface of the second rotating shaft along the circumference of the second rotating shaft, and the openings of the plurality of weight-reducing grooves face the first rotating shaft.

11. The permanent magnet motor according to claim 8, characterized in that: The first rotating shaft is defined as having two ends along its axial direction as a first section and a second section respectively, the length of the first section along the axial direction of the first rotating shaft is consistent with the length of the second section along the axial direction of the first rotating shaft; the volume of the first section is greater than the volume of the second section; Or the first section is provided with an extension piece for increasing the volume of the first section, and the extension piece is fixed on the first section or is integrally formed with the first section.

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