Motor, compressor and refrigeration equipment

Abstract

The invention provides a motor, a compressor and refrigeration equipment. The motor comprises a rotor; the mounting groove is formed in the rotor; the permanent magnets are arranged in the mounting grooves and form magnetic poles, the center line of any magnetic pole passing through the axis of the rotor is set as a D axis, the distance between the intersection point of the D axis and the outer edge of the rotor and the intersection point of the D axis and the wall face, close to the outer edge of the rotor, of the mounting groove is L1, the minimum distance between the mounting groove and the outer edge of the rotor is L2, and L1 is a positive integer; according to the invention, the anti-demagnetization capability of the permanent magnet can be effectively improved, the magnet demagnetization risk of the motor in the use process is avoided, and the maintenance times and the maintenance frequency are reduced.

Description

[0001] This application is a divisional application of a Chinese patent application with an application date of September 28, 2020, an application number of "202011039176.X", and an invention title of "Motor, Compressor, and Refrigeration Equipment". Technical Field

[0002] The present invention relates to the technical field of motors, and in particular, to a motor, a compressor, and a refrigeration equipment. Background Art

[0003] For compressors used in refrigeration equipment such as air conditioners, variable-frequency motors have become the mainstream technology, fixed-speed models have gradually withdrawn from the market, and full variable-frequency has arrived. Currently, the motors of variable-frequency compressors are developing towards a design structure with multiple slots and multiple poles. However, during the operation of the motor, the permanent magnet will experience local demagnetization, requiring frequent maintenance, which seriously affects the normal use of the motor. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0005] To this end, in the first aspect of the present invention, a motor is provided.

[0006] In the second aspect of the present invention, a compressor is provided.

[0007] In the third aspect of the present invention, a refrigeration equipment is provided.

[0008] The first aspect of the present invention provides a motor, including: a rotor; a mounting groove provided on the rotor; a permanent magnet provided in the mounting groove and forming magnetic poles, and setting the center line of any magnetic pole passing through the axis of the rotor as the D axis. Among them, the distance between the intersection point of the D axis and the outer edge of the rotor and the intersection point of the D axis and a wall surface of the mounting groove close to the outer edge of the rotor is L1, and the minimum distance between the mounting groove and the outer edge of the rotor is L2, satisfying

[0009] The motor proposed by the present invention includes a rotor, a mounting groove, and a permanent magnet. Among them, the mounting groove is provided on the rotor and can provide a mounting position for the permanent magnet. The permanent magnet is provided in the mounting groove and can form magnetic poles within the rotor. In particular, the center line of any magnetic pole passing through the axis of the rotor is set as the D axis. There is an intersection point between the D axis and the outer edge of the rotor, and there is also an intersection point between the D axis and a wall surface of the mounting groove close to the outer edge of the rotor. The distance between these two intersection points is L1, and the minimum distance between the mounting groove and the outer edge of the rotor is L2, and it satisfies

[0010] Particularly, in the demagnetized state, after the magnetic field lines on the stator side reach the rotor, a small portion of the magnetic field lines directly pass through the mounting grooves and the permanent magnets, which may cause a decrease in the remanence of the permanent magnets or local irreversible demagnetization, while most of the magnetic field lines return to the stator. Moreover, during the operation of the motor, after the magnetic field reaches the rotor, the magnetic field lines will shift. Particularly, since the minimum distance L2 between the mounting groove and the outer edge of the rotor is small, the magnetic flux density gradually increases and saturates. The ratio of dimension L1 to dimension L2 can reflect the change rate of the path-length permeance. It should be noted that the size of L2 is generally constant at about 0.5 mm, and the larger the size of L1, the greater the change rate of the ratio of L1 to dimension L2, which may cause a small portion of the magnetic field lines to pass through the mounting groove. Therefore, in the present invention, the size of L1 is designed to be relatively small, so that L2 / L1 is increased compared with the related art, so that Based on the solution defined in the present invention, the demagnetization resistance of the permanent magnet can be effectively enhanced, the demagnetization risk during the use of the motor can be effectively avoided, the maintenance can be reduced, and the output torque and output capacity of the motor can be guaranteed.

[0011] That is to say, the present invention optimizes the shape and installation position of the mounting groove, effectively improves the demagnetization resistance of the permanent magnet, can effectively avoid the demagnetization risk of the magnet during the use of the motor, and reduces the number and frequency of maintenance.

[0012] According to the motor of the above technical solution of the present invention, the following additional technical features may also be included:

[0013] In the above technical solution, the mounting groove includes: a first groove body; a second groove body, which is connected to the first groove body at the D axis, and the first groove body and the second groove body are distributed in a V shape.

[0014] In this technical solution, the mounting groove includes a first groove body and a second groove body. Among them, the first groove body is connected to the second groove body and is used for installing the permanent magnet. In addition, the first groove body and the second groove body are distributed in a V shape, and the D axis is the axis of symmetry of the first groove body and the second groove body. That is to say, the L1 defined in the present invention is the distance between the axis of symmetry of the first groove body and the second groove body and the two intersection points between the outer edge of the rotor and a wall surface of the mounting groove close to the outer edge of the rotor.

[0015] Particularly, the demagnetized area of the stator includes the position where the first groove body is connected to the second groove body, that is, includes the cusp of the V shape. For this reason, the present invention defines that the D axis is the axis of symmetry of the first groove body and the second groove body, that is, it ensures the dimension of the cusp of the V shape from the outer edge of the rotor.

[0016] In any of the above technical solutions, the number of the mounting grooves is 2P, and the 2P mounting grooves are circumferentially distributed along the rotor; the angular bisector of two adjacent D axes is the Q axis, the first groove body extends from the D axis towards the Q axis, and L2 is the minimum distance between the first groove body and the outer edge of the rotor.

[0017] In this technical solution, the number of mounting grooves is 2P, and the 2P mounting grooves are evenly distributed along the circumferential direction of the rotor to form evenly distributed magnetic poles in the circumferential direction of the rotor, ensuring the stable operation of the motor using this rotor. Specifically, P can be an integer such as 1, 2, 3, 4, 5, etc.

[0018] In addition, the angular bisector of two adjacent D axes is the Q axis along the circumferential direction of the rotor. The first groove extends from the D axis towards the Q axis, and along the radial direction of the rotor, the first groove extends from the axial direction of the rotor towards the outer edge. In addition, L2 is the minimum distance between the first groove and the outer edge of the rotor, that is, L2 is the minimum distance between the first groove and the outer edge of the rotor at the Q axis.

[0019] Specifically, in the demagnetized state, the reverse magnetic field generated at the stator causes the magnetic field lines to pass through the stator teeth and the air gap to reach the rotor, causing demagnetization of the rotor. After the magnetic field lines on the stator side reach the rotor, a small part of the magnetic field lines directly pass through the mounting grooves and the permanent magnets, resulting in a decrease in the remanence of the permanent magnets or local irreversible demagnetization. Most of the magnetic field lines pass through the magnetic isolation bridge at the Q axis, pass through the air gap, and return to the stator. The present invention designs the size of L1 to be relatively small, so that Furthermore, the magnetic field lines passing through the mounting grooves and the permanent magnets are reduced, so that more magnetic field lines return to the stator, enhancing the demagnetization resistance of the stator and avoiding the demagnetization risk during the use of the motor.

[0020] In any of the above technical solutions, the motor further includes: a stator, on which a plurality of stator teeth are provided. The tooth top walls of the plurality of stator teeth are collinear with the same stator inner circle. The diameter of the stator inner circle is Di, and the width of the tooth top wall of the stator teeth is L3, satisfying

[0021] In this technical solution, the motor further includes a stator, which can cooperate with the rotor to output torque. Among them, a plurality of stator teeth are provided on the stator. The plurality of stator teeth extend towards the axis core of the stator, and the tooth top walls of the plurality of stator teeth are collinear with the same stator inner circle inside the stator. In particular, the diameter of this stator inner circle is Di, and the width of the tooth top wall of the stator teeth is L3, satisfying

[0022] In particular, in the demagnetized state, the reverse magnetic field generated at the stator causes the magnetic field lines to pass through the stator teeth and the air gap to reach the rotor, causing demagnetization of the rotor. After the magnetic field on the stator side reaches the rotor, a small part of the magnetic field lines directly pass through the mounting grooves and the permanent magnets, resulting in a decrease in the remanence of the permanent magnets or local irreversible demagnetization. Most of the magnetic field lines pass through the magnetic isolation bridge at the Q axis, pass through the air gap, and return to the stator.

[0023] Due to the existence of the stator slot opening, the span of the top of the stator tooth in the inner diameter of the stator (i.e., dimension L3) determines how many magnetic lines of force pass through the air gap to reach the rotor. According to the simulation calculation, the dimension range is converged. A too small proportion means a large slot opening, which deteriorates the cogging torque and torque ripple, and also deteriorates the demagnetization; a too large proportion means more magnetic fields reach the rotor, and the demagnetization will also deteriorate. Therefore, the present invention limits such that is within a suitable range, ensuring that the risk of demagnetization of the permanent magnet is reduced.

[0024] In any of the above technical solutions, a straight line parallel to the D-axis and at a distance of L3 / 2 from the D-axis is set as the P-axis. The distance between the two intersection points of the P-axis and the outer edge of the rotor and a wall surface of the installation groove close to the outer edge of the rotor is L4, and it satisfies

[0025] In this technical solution, a straight line parallel to the D-axis and at a distance of L3 / 2 from the D-axis is set as the P-axis. Among them, there is an intersection point between the P-axis and the outer edge of the rotor, and there is also an intersection point between the P-axis and a wall surface of the installation groove close to the outer edge of the rotor. The distance between these two intersection points is L4, and it satisfies

[0026] It should be noted that from L1 to L4, it can be considered as a process in which the magnetic lines of force coming from the stator side are gradually accepted and the magnetic conductance gradually decreases. From L4 to L2, it is a process in which all the magnetic lines of force coming from the stator are gradually compressed and saturated (the magnetic conductance gradually decreases), and the change rate of the magnetic conductance behind is less than that in front. Among them, from L1 to L4, the width change of the magnetic circuit is L1→L4, and the length change of the magnetic circuit is L3 / 2; from L4 to L2, the width change of the magnetic circuit is L4→L2, and the length change of the magnetic circuit is τ is the pole pitch, τ = π×Di1 / 2 / P. Therefore, after simplification, it can be obtained that Therefore, the present invention limits which can further enhance the demagnetization resistance ability of the stator and avoid the demagnetization risk during the use of the motor.

[0027] In any of the above technical solutions, the number 2P of the installation grooves is 8 or 10; the number of the stator teeth is 12.

[0028] In this technical solution, the number of the installation grooves can be 8 or 10. Correspondingly, the number of the stator teeth is 12. The motor with the above number of installation grooves and stator teeth has good demagnetization resistance ability and can effectively avoid the demagnetization phenomenon during use.

[0029] In any of the above technical solutions, L2 is greater than or equal to 0.5 mm.

[0030] In this technical solution, L2 is greater than or equal to 0.5 mm. By defining that L2 is greater than or equal to 0.5 mm, that is, defining the installation position of the installation groove on the rotor, based on the above definition, the motor has good anti-demagnetization ability, and the demagnetization phenomenon can be effectively avoided during use.

[0031] In any of the above technical solutions, an included angle is formed between the first groove body and the second groove body, and the value range of the included angle is 100° to 130°.

[0032] In this technical solution, an included angle is formed between the first groove body and the second groove body, and the value range of the included angle is 100° to 130°. That is to say, the included angle formed between the first groove body and the second groove body should be greater than or equal to 100° and less than or equal to 130°. Based on the limitation of the size of the included angle formed between the first groove body and the second groove body, the structure of the installation groove can be ensured to be appropriate, and at the same time, the circumferential distribution of the installation groove and the rotor can be ensured to be appropriate, ensuring that an appropriate number of installation grooves are provided on the rotor. Moreover, the anti-demagnetization ability of the rotor can be further improved, the demagnetization phenomenon can be improved, and the working efficiency and output capacity of the compressor can be ensured.

[0033] Specifically, the included angle formed between the first groove body and the second groove body can be 100°, 105°, 110°, 115°, 120°, 125°, 130°, etc.

[0034] In any of the above technical solutions, a transition fillet is provided at the connection of the first groove body and the second groove body. The transition fillet is located on a wall surface of the installation groove close to the outer edge of the rotor, and the radius is greater than or equal to 0.5 mm.

[0035] In this technical solution, the rotor further includes a transition fillet. Among them, the transition fillet is provided at the position where the first groove body and the second groove body are connected, that is, at the tip of the V shape, and the transition fillet is located on a wall surface of the installation groove close to the outer edge of the rotor. The setting of the transition fillet can avoid the existence of a sharp point at the connection of the first groove body and the second groove body, and can avoid the situation of stress concentration at the connection of the first groove body and the second groove body.

[0036] The second aspect of the present invention provides a compressor, including: a motor as in the first aspect of the present invention.

[0037] The compressor proposed by the present invention includes a motor as in the first aspect of the present invention. Therefore, it has all the beneficial effects of the above-mentioned rotor, which will not be elaborated one by one here.

[0038] The third aspect of the present invention provides a refrigeration device, including: a compressor as in the second aspect of the present invention.

[0039] The refrigeration device proposed by the present invention includes a compressor as described in the second aspect of the present invention. Therefore, it also has all the beneficial effects of the above-mentioned rotor, which will not be elaborated one by one here.

[0040] Specifically, the refrigeration device proposed by the present invention can be an air conditioner, a refrigerator, a freezer, a display cabinet, etc.

[0041] In any of the above technical solutions, the permanent magnet is arranged in the installation groove to form a magnetic pole, and the permanent magnet does not contain the heavy rare earth elements dysprosium and terbium.

[0042] In any of the above technical solutions, the D-axis is also the middle symmetry line of the "V" shape, and the Q-axis is also the symmetry line between two adjacent installation grooves.

[0043] In any of the above technical solutions, L1 is the distance between the intersection of the D-axis and the outer edge of the rotor and the intersection of the installation groove, L2 is the minimum gap between the installation groove near the Q-axis and the outer edge of the rotor, L3 is the distance between the two intersection points of the stator teeth at the inner circle of the stator, and L4 is the distance between the straight line parallel to the D-axis and at a distance of L3 / 2 from the D-axis and the intersection of the outer edge of the rotor and the installation groove.

[0044] In any of the above technical solutions, the installation groove is the permanent magnet groove.

[0045] In any of the above technical solutions, there is no air magnetic isolation gap (slit) on the side of the installation groove close to the outer edge of the rotor.

[0046] The additional aspects and advantages of the present invention will become obvious in the following description section, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, where:

[0048] Figure 1 is a schematic structural diagram of a rotor in a motor according to an embodiment of the present invention;

[0049] Figure 2 is Figure 1 a partial enlarged view of the A position of the rotor of the shown embodiment;

[0050] Figure 3 is a schematic structural diagram of a stator in a motor according to an embodiment of the present invention.

[0051] Among them, Figures 1 to 3 the corresponding relationship between the reference numerals in the drawings and the component names is:

[0052] 102 rotor, 104 installation groove, 1042 first groove body, 1044 second groove body, 106 stator, 108 stator teeth. Detailed implementation manners

[0053] In order to more clearly understand the above objects, features, and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0054] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0055] The following will refer to Figures 1 to 3 to describe a motor, a compressor, and a refrigeration device according to some embodiments of the present invention.

[0056] Embodiment 1:

[0057] As Figure 1 and Figure 2 shown, a first embodiment of the present invention provides a motor, including: a rotor 102, a mounting groove 104, and a permanent magnet. Among them, the mounting groove 104 is provided on the rotor 102 and can provide a mounting position for the permanent magnet. The permanent magnet is arranged in the mounting groove 104 and can form magnetic poles in the rotor 102.

[0058] Among them, as Figure 1 shown, the center line of any magnetic pole passing through the axis of the rotor 102 is set as the D axis. There is an intersection between the D axis and the outer edge of the rotor 102, and there is also an intersection between the D axis and a wall surface of the mounting groove 104 close to the outer edge of the rotor 102; as Figure 2 shown, the distance between these two intersections is L1, and the minimum distance between the mounting groove 104 and the outer edge of the rotor 102 is L2, and it satisfies

[0059] Specifically, in the demagnetized state, after the magnetic lines of force on the stator 106 side reach the rotor 102, a small part of the magnetic lines of force directly pass through the mounting groove 104 and the permanent magnet, which will cause a decrease in the remanence of the permanent magnet or local irreversible demagnetization, while most of the magnetic lines of force return to the stator 106. Moreover, during the operation of the motor, after the magnetic field reaches the rotor 102, the magnetic lines of force shift.

[0060] Specifically, since the minimum distance L2 between the mounting groove 104 and the outer edge of the rotor 102 is small, the magnetic density gradually increases and saturates. The ratio of the size L1 to the size L2 can reflect the change rate of the path-length magnetic conductance. It should be noted that the size of L2 is generally constant at about 0.5 mm, and the larger the size of L1, the greater the change rate of the ratio of L1 to the size L2, which may cause a small part of the magnetic lines of force to pass through the mounting groove 104.

[0061] Therefore, in this embodiment, the size of L1 is designed to be relatively small, so that L2 / L1 is increased compared with the related art, making Based on the solution defined in the present invention, the demagnetization resistance of the permanent magnet can be effectively enhanced, the demagnetization risk during the use of the motor can be effectively avoided, the maintenance can be reduced, and the output torque and output capacity of the motor can be ensured.

[0062] That is to say, in this embodiment, the shape and installation position of the installation groove 104 are optimized, effectively improving the demagnetization resistance of the permanent magnet, effectively avoiding the magnet demagnetization risk during the use of the motor, and reducing the number and frequency of maintenance.

[0063] In this embodiment, further, as Figure 1 and Figure 2 shown, the installation groove 104 includes a first groove body 1042 and a second groove body 1044. Among them, the first groove body 1042 is communicated with the second groove body 1044 and is used for installing the permanent magnet. In addition, the first groove body 1042 and the second groove body 1044 are distributed in a V shape, and the D axis is the axis of symmetry of the first groove body 1042 and the second groove body 1044. That is to say, the L1 defined in this embodiment is the distance between the two intersection points of the axis of symmetry of the first groove body 1042 and the second groove body 1044 and the outer edge of the rotor 102 and a wall surface of the installation groove 104 close to the outer edge of the rotor 102.

[0064] Particularly, the demagnetization region of the stator 106 includes the position where the first groove body 1042 is communicated with the second groove body 1044, that is, includes the cusp of the V shape. For this reason, in this embodiment, the D axis is defined as the axis of symmetry of the first groove body 1042 and the second groove body 1044, that is, ensuring the size of the cusp of the V shape from the outer edge of the rotor 102.

[0065] In this embodiment, further, the number of the installation grooves 104 is 2P, and the 2P installation grooves 104 are evenly distributed along the circumferential direction of the rotor 102 to form evenly distributed magnetic poles in the circumferential direction of the rotor 102, ensuring the stable operation of the motor applying the rotor 102. Specifically, P can be an integer such as 1, 2, 3, 4, etc.

[0066] And, the angular bisector of two adjacent D axes is the Q axis. Along the circumferential direction of the rotor 102, the first groove body 1042 extends from the D axis towards the Q axis. Along the radial direction of the rotor 102, the first groove body 1042 extends from the axial direction of the rotor 102 towards the outer edge. In addition, L2 is the minimum distance between the first groove body 1042 and the outer edge of the rotor 102, that is, L2 is the minimum distance between the first groove body 1042 and the outer edge of the rotor 102 at the Q axis.

[0067] Specifically, in the demagnetized state, a reverse magnetic field is generated at the stator 106. The magnetic field lines pass through the stator teeth 108 and the air gap to reach the rotor 102, causing demagnetization of the rotor 102. After the magnetic field lines reach the rotor 102 on the stator 106 side, a small portion of the magnetic field lines directly pass through the mounting groove 104 and the permanent magnet, resulting in a decrease in the remanence of the permanent magnet or local irreversible demagnetization. Most of the magnetic field lines pass through the magnetic isolation bridge at the Q-axis, pass through the air gap, and return to the stator 106. In the present invention, the size of L1 is designed to be relatively small, so that further reduces the magnetic field lines passing through the mounting groove 104 and the permanent magnet, enabling more magnetic field lines to return to the stator 106, enhancing the demagnetization resistance of the stator 106, and avoiding the demagnetization risk during the use of the motor.

[0068] Embodiment 2:

[0069] As Figure 1 、 Figure 2 and Figure 3 shown, the second embodiment of the present invention proposes a motor, including: a rotor 102, 2P mounting grooves 104, a permanent magnet, and a stator 106. Among them, the mounting grooves 104 are provided on the rotor 102 and can provide a mounting position for the permanent magnet. The permanent magnet is arranged in the mounting groove 104 and can form magnetic poles within the rotor 102.

[0070] Among them, as Figure 1 shown, the center line of any magnetic pole passing through the axis of the rotor 102 is set as the D-axis, and the angular bisector of two adjacent D-axes is the Q-axis. As Figure 2 shown, L1 is the distance between two intersection points of the D-axis and the outer edge of the rotor 102 and a wall surface of the mounting groove 104 close to the outer edge of the rotor 102, and L2 is the minimum distance between the first groove body 1042 and the outer edge of the rotor 102, and it satisfies

[0071] In addition, as Figure 3 shown, the motor further includes a stator 106, and the stator 106 can cooperate with the rotor 102 to output torque. Among them, a plurality of stator teeth 108 are provided on the stator 106, and the plurality of stator teeth 108 extend towards the axis of the stator 106, and the tooth top walls of the plurality of stator teeth 108 are collinear with the same stator inner circle inside the stator 106. Particularly, the diameter of the stator inner circle is Di, and the width of the tooth top wall of the stator tooth 108 is L3, satisfying

[0072] In particular, in the demagnetized state, a reverse magnetic field is generated at the stator 106. The magnetic force lines pass through the stator teeth 108 and the air gap to reach the rotor 102, causing demagnetization of the rotor 102. After the magnetic field on the stator 106 side reaches the rotor 102, a small portion of the magnetic force lines directly pass through the mounting groove 104 and the permanent magnet, resulting in a decrease in the remanence of the permanent magnet or local irreversible demagnetization. Most of the magnetic force lines pass through the magnetic isolation bridge at the Q-axis, pass through the air gap, and return to the stator 106.

[0073] Due to the existence of the stator 106 slot opening, the span (dimension L3) of the top of the stator tooth 108 on the inner diameter of the stator 106 determines how many magnetic force lines pass through the air gap to reach the rotor 102. According to simulation calculations, the dimension range is obtained. An overly small proportion means a large slot opening, deteriorating cogging torque and torque ripple, and deteriorating demagnetization. An overly large proportion means more magnetic fields reach the rotor 102, and demagnetization also deteriorates. Therefore, the present invention defines such that is within a suitable range, ensuring a reduced risk of demagnetization of the permanent magnet.

[0074] In this embodiment, further, as shown in Figure 2 and Figure 3 , a straight line parallel to the D-axis and at a distance of L3 / 2 from the D-axis is defined as the P-axis. Among them, there is an intersection point between the P-axis and the outer edge of the rotor 102, and there is also an intersection point between the P-axis and a wall surface of the mounting groove 104 close to the outer edge of the rotor 102. The distance between these two intersection points is L4, and it satisfies

[0075] It should be noted that from L1 to L4, it can be considered as a process in which the magnetic force lines coming from the stator 106 side gradually accept and the magnetic conductance gradually decreases. From L4 to L2, it is a process in which all the magnetic force lines coming from the stator 106 are gradually compressed and saturated (the magnetic conductance gradually decreases), and the change rate of the magnetic conductance behind is smaller than that in front. Among them, from L1 to L4, the width change of the magnetic circuit is L1→L4, and the length change of the magnetic circuit is L3 / 2; from L4 to L2, the width change of the magnetic circuit is L4→L2, and the length change of the magnetic circuit is τ is the pole pitch, τ = π×Di1 / 2 / P. Therefore, after simplification, it can be obtained that Therefore, the present invention defines which can further enhance the demagnetization resistance ability of the stator 106 and avoid the demagnetization risk during the use of the motor.

[0076] In addition, since the motor proposed in this embodiment also satisfies Therefore, it has all the beneficial effects of the motor proposed in Embodiment 1, and will not be elaborated one by one here.

[0077] On the basis of the first embodiment and the second embodiment, further, the number of the mounting grooves 104 may be 8 or 10. Correspondingly, as Figure 3 shown, the number of the stator teeth 108 is 12. The motor with the above numbers of the mounting grooves 104 and the stator teeth 108 has good demagnetization resistance ability and can effectively avoid the demagnetization phenomenon during use.

[0078] On the basis of the first embodiment and the second embodiment, further, as Figure 2 shown, L2 is greater than or equal to 0.5 mm. By defining that L2 is greater than or equal to 0.5 mm, that is, defining the setting position of the mounting groove 104 on the rotor 102, based on the above definition, the motor has good demagnetization resistance ability and can effectively avoid the demagnetization phenomenon during use.

[0079] On the basis of the first embodiment and the second embodiment, further, as Figure 2 shown, an included angle is formed between the first groove body 1042 and the second groove body 1044, and the value range of the included angle is between 100° and 130°. That is to say, the included angle formed between the first groove body 1042 and the second groove body 1044 should be greater than or equal to 100° and less than or equal to 130°. Based on the limitation of the size of the included angle formed between the first groove body 1042 and the second groove body 1044, the structure of the mounting groove 104 can be ensured to be suitable, and at the same time, the circumferential distribution of the mounting groove 104 on the rotor 102 can be ensured to be suitable, ensuring that an appropriate number of mounting grooves 104 are provided on the rotor 102, and further, the demagnetization resistance ability of the rotor 102 can be improved, the demagnetization phenomenon can be improved, and the working efficiency and output ability of the compressor can be ensured.

[0080] Specifically, the included angle formed between the first groove body and the second groove body may be 100°, 105°, 110°, 115°, 120°, 125°, 130°, etc.

[0081] On the basis of the first embodiment and the second embodiment, further, as Figure 2 shown, the rotor 102 further includes a transition fillet. Among them, the transition fillet is arranged at the position where the first groove body 1042 and the second groove body 1044 are connected, that is, at the cusp of the V shape, and the transition fillet is located on a wall surface of the mounting groove close to the outer edge of the rotor 102. The setting of the transition fillet can avoid the existence of a cusp at the connection of the first groove body 1042 and the second groove body 1044 and can avoid the situation of stress concentration at the connection of the first groove body 1042 and the second groove body 1044.

[0082] On the basis of the first embodiment and the second embodiment, further, the permanent magnet is arranged in the mounting groove 104 to form magnetic poles, and the permanent magnet does not contain the heavy rare earth elements dysprosium and terbium.

[0083] Based on Embodiment 1 and Embodiment 2, as Figure 1 shown, the D axis is also the symmetric line in the middle of the "V" shape, and the Q axis is also the symmetric line between the two mounting grooves 104.

[0084] Based on Embodiment 1 and Embodiment 2, as Figure 2 and Figure 3 shown, L1 is the distance between the intersection point of the D axis and the outer edge of the rotor 102 and the intersection point of the mounting groove 104, L2 is the minimum clearance between the mounting groove 104 near the Q axis and the outer edge of the rotor 102, L3 is the distance between the two intersection points on both sides of the stator tooth 108 at the inner circle of the stator, and L4 is the distance between the straight line parallel to the D axis and at a distance of L3 / 2 from the D axis and the intersection point of the outer edge of the rotor 102 and the mounting groove 104.

[0085] Based on Embodiment 1 and Embodiment 2, the mounting groove 104 is the permanent magnet groove.

[0086] Embodiment 3:

[0087] The third embodiment of the present invention provides a compressor, including: a motor as in Embodiment 1 or Embodiment 2 of the present invention (this embodiment is not shown in the figure).

[0088] The compressor proposed in this embodiment, because it includes a motor as in Embodiment 1 or Embodiment 2 of the present invention. Therefore, it also has all the beneficial effects of the above-mentioned rotor 102, which will not be elaborated one by one here.

[0089] Embodiment 4:

[0090] The fourth embodiment of the present invention provides a refrigeration device, including: a compressor as in Embodiment 3 of the present invention (this embodiment is not shown in the figure).

[0091] The refrigeration device proposed in this embodiment, because it includes a compressor as in Embodiment 3 of the present invention. Therefore, it also has all the beneficial effects of the above-mentioned rotor 102, which will not be elaborated one by one here.

[0092] Specifically, the refrigeration device proposed in this embodiment can be an air conditioner, a refrigerator, a freezer, a display cabinet, etc. Specific Embodiment:

[0094] For compressors of existing household appliances such as household air conditioners, variable-frequency motors have become the mainstream technology. Especially with the new national energy efficiency grade standard for household air conditioners promulgated in 2019, constant-speed models have gradually withdrawn from the market, and full variable-frequency has arrived. To adapt to the application environment of household air conditioners, the permanent magnets of variable-frequency motors are mostly neodymium-iron-boron permanent magnets containing heavy rare-earth elements and having a relatively high coercivity. However, with the increasing total number of variable-frequency models year by year, the consumption of the national strategic resource heavy rare-earth elements (especially dysprosium and terbium) has also increased year by year. In order to reduce the consumption of strategic resources, application research on heavy-rare-earth-free neodymium-iron-boron permanent magnets needs to be carried out.

[0095] The application of heavy-rare-earth-free permanent magnets needs to be combined with the design structure of a multi-slot and multi-pole motor. Since the number of poles increases, the magnetic density of the yoke part of the stator teeth 108 of the motor needs to be correspondingly reduced to avoid excessive iron loss and reduced efficiency of the motor.

[0096] For this reason, as Figure 1 、 Figure 2 and Figure 3 shown, this embodiment provides a motor and a compressor. Among them, the motor includes: a rotor 102, on which there are 2P mounting slots 104 containing neodymium-iron-boron permanent magnets that do not contain the heavy rare-earth elements dysprosium and terbium; the mounting slots 104 are V-shaped. As Figure 2 shown, the middle symmetry line of the V-shape is the D axis, and the symmetry line between the two mounting slots 104 is the Q axis; the distance between the intersection point of the D axis and the outer edge of the rotor 102 and the intersection point of the mounting slot 104 is L1, and the minimum gap between the mounting slot 104 near the Q axis and the outer edge of the rotor 102 is L2. As Figure 3 shown, a stator 106, on which there is a stator inner circle and stator teeth 108. The diameter of the stator inner circle is Di, and the distance between the two intersection points of the stator teeth 108 at the stator inner circle is L3.

[0097] As Figure 2 and Figure 3 shown, the straight line parallel to the D axis and at a distance of L3 / 2, and the distance between the outer edge of the rotor 102 and the intersection point of the rotor 102 slot is L4. For the motor proposed according to this embodiment, its demagnetization resistance is enhanced, which can effectively avoid the risk of magnet demagnetization during the use of the motor and reduce maintenance.

[0098] In addition, as Figure 1 shown, the number of mounting slots 104, 2P = 8 or 10. As Figure 3 shown, the number of stator teeth 108 is 12; on the side of the mounting slot 104 close to the outer edge of the rotor 102, there is no air magnetic isolation gap (slit).

[0099] In a specific embodiment, in the demagnetized state, a reverse magnetic field is generated at the stator 106. The reverse magnetic field passes through the stator teeth 108 and the air gap to reach the rotor 102, causing demagnetization of the rotor 102. After the magnetic field on the stator 106 side reaches the rotor 102, a small part of the reverse magnetic field directly passes through the mounting groove 104 and the magnet, resulting in a decrease in the remanence of the magnet or local irreversible demagnetization. Most of the reverse magnetic field passes through the magnetic isolation bridge on the Q-axis, passes through the air gap, and returns to the stator 106.

[0100] Due to the existence of the stator slot opening of the stator 106, the span (dimension L3) of the top of the stator tooth 108 on the inner diameter of the stator 106 determines how many magnetic lines of force pass through the air gap to reach the rotor 102. According to simulation calculations, the size range is obtained. If the proportion is too small, it means the slot opening is very large, the cogging torque and torque ripple deteriorate, and the demagnetization also deteriorates. If the proportion is too large, it means more magnetic fields reach the rotor 102, and the demagnetization will also deteriorate.

[0101] After the magnetic field reaches the rotor 102, the magnetic lines of force shift towards the Q-axis. Since the width of the magnetic isolation bridge (dimension L2) at the Q-axis is relatively narrow, the magnetic flux density gradually increases and saturates. The ratio of dimension L1 to dimension L2 can reflect the change rate of the path length magnetic conductance. The size of L2 is generally constant at about 0.5 mm. The larger the size of L1, the larger the change rate, which may cause a small part of the magnetic lines of force to pass through the mounting groove 104. Therefore, if the size of L1 is designed to be smaller, then L2 / L1 increases compared to the existing size.

[0102] Extending downward from the top of the stator tooth 108 forms dimension L4. From L1 to L4, it can be considered as a process in which the magnetic lines of force coming from the stator 106 side are gradually accepted and the magnetic conductance gradually decreases. From L4 to L2, it is a process in which all the magnetic lines of force coming from the stator 106 are gradually compressed and saturated (the magnetic conductance gradually decreases), and the change rate of the magnetic conductance behind is smaller than that in front.

[0103] From L1 to L4, the width change of the magnetic circuit is L1→L4, and the length change of the magnetic circuit is L3 / 2; from L4 to L2, the width change of the magnetic circuit is L4→L2, and the length change of the magnetic circuit is (τ - L3) / 2, where τ is the pole pitch, τ = π×Di / 2 / P. Therefore After simplification, it can be obtained that

[0104] Next, referring to Table 1, it can be clearly seen that the values of the motor proposed by the present invention in these four aspects are all significantly different from the related technologies, thereby improving the anti-demagnetization ability of the motor. Among them, the numbers 1 to 4 in Table 1 are the parameters of the related technologies, and the number 5 is the parameter of a specific embodiment of the present invention.

[0105] Table 1

[0106]

[0107] In the description of the present invention, the term "a plurality of" means two or more, unless otherwise clearly defined. The orientation or positional relationship indicated by terms such as "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings, and is 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 should not be construed as a limitation to the present invention; the terms "connection", "installation", "fixation", etc. should all be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0108] In the description of this specification, the descriptions of terms such as "one embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or instance. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0109] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A motor, characterized in that, it comprises: a rotor; a mounting groove provided on the rotor; a permanent magnet provided in the mounting groove and forming magnetic poles, and the center line of any one of the magnetic poles passing through the axis of the rotor is set as the D axis, Among them, the distance between the intersection point of the D axis and the outer edge of the rotor and the intersection point of the D axis and a wall surface of the installation groove close to the outer edge of the rotor is L1, and the minimum distance between the installation groove and the outer edge of the rotor is L2, satisfying 2. The motor according to claim 1, characterized in that, the mounting groove comprises: a first groove body; a second groove body communicating with the first groove body at the D axis, and the first groove body and the second groove body are distributed in a V shape.

3. The motor according to claim 2, characterized in that, the number of the mounting grooves is 2P, and the 2P mounting grooves are circumferentially distributed along the rotor; the angular bisector of two adjacent D axes is the Q axis, the first groove body extends from the D axis towards the Q axis, and L2 is the minimum distance between the first groove body and the outer edge of the rotor.

4. The motor according to claim 3, characterized in that, it further comprises: Stator, on which a plurality of stator teeth are provided, the top walls of the plurality of stator teeth being collinear with the same stator inner circle, the diameter of the stator inner circle being Di, and the width of the top wall of the stator tooth being L3, satisfying 5. The motor according to claim 4, characterized in that, Let the straight line parallel to the D axis and at a distance of L3 / 2 from the D axis be the P axis. The distance between the two intersection points of the P axis and the outer edge of the rotor and a wall surface of the installation groove close to the outer edge of the rotor is L4, satisfying 6. The motor according to claim 4, characterized in that, the number 2P of the mounting grooves is 8 or 10.

7. The motor according to any one of claims 1 to 6, characterized in that, L2 is greater than or equal to 0.5 mm.

8. The motor according to any one of claims 4 to 6, characterized in that, an included angle is formed between the first groove body and the second groove body, and the value range of the included angle is 100° to 130°; and / or a transition fillet is provided at the communication position of the first groove body and the second groove body, the transition fillet is located on a wall surface of the mounting groove close to the outer edge of the rotor, and the radius is greater than or equal to 0.5 mm.

9. A compressor, characterized in that, it comprises: the motor according to any one of claims 1 to 8.

10. A refrigeration device, characterized in that, it comprises: the compressor according to claim 9.

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