Tangential motor, compressor, air conditioner

Abstract

The application provides a tangential motor, a compressor and an air conditioner, wherein the tangential motor comprises a rotor assembly, the rotor assembly comprises a rotor core, a magnetic steel slot is arranged in each magnetic pole of the rotor core, a rare earth permanent magnet and a ferrite permanent magnet are arranged in the magnetic steel slot, the rare earth permanent magnet is rectangular, the rare earth permanent magnet is quadrilateral, the ferrite permanent magnet has a radial inner side adjacent to an axial hole, the rare earth permanent magnet is located at a radial outer side of the ferrite permanent magnet and is connected with the radial outer side in contact, and the rare earth permanent magnet and the ferrite permanent magnet are both symmetrical about the center line of the corresponding magnetic steel slot. According to the application, the cost caused by the single use of the rare earth permanent magnet is effectively prevented, the insufficient performance of the motor caused by the single use of the ferrite permanent magnet is effectively prevented, and the tangential motor of the application has relatively low manufacturing cost while ensuring relatively high performance of the motor.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of motor manufacturing, and particularly relates to a tangential motor, a compressor and an air conditioner. BACKGROUND

[0002] At present, household air conditioners have become increasingly popular, and are the main contributors to household or building energy consumption. In order to effectively save energy and reduce emissions, China has introduced the new standard "(GB21455-2019) Energy Efficiency Limits and Energy Efficiency Grades for Room Air Conditioners" in a timely manner, with the goal of eliminating 60-70% of products on the market (based on 2019), while further increasing the proportion of variable frequency air conditioners to achieve more than 90%. However, China produces more than 80% of the world's air conditioners, and the Chinese government plans to increase energy-saving targets by more than 30% by 2022. The first energy efficiency value of the new standard will reach an internationally leading level.

[0003] In order to meet such high energy efficiency requirements, the air conditioner compressor industry usually optimizes the design of traditional radial permanent magnet synchronous motors, such as adjusting the ratio of stator and rotor, using high-performance permanent magnets and silicon steel sheets, and optimizing the arrangement of rotor permanent magnets. However, the efficiency of such motors is limited, and the cost is relatively high (for example, using more expensive and better performing rare earth samarium-cobalt permanent magnets), which puts a lot of pressure on business operations. SUMMARY

[0004] Therefore, the technical problem to be solved by the present application is to provide a tangential motor, a compressor and an air conditioner to overcome the low efficiency and high cost of the motor in the prior art.

[0005] In order to solve the above problems, the present application provides a tangential motor, comprising a rotor assembly, the rotor assembly comprising a rotor core, the rotor core having a plurality of magnetic poles, each of the magnetic poles being configured with a magnetic steel slot, the magnetic steel slot being provided with a rare earth permanent magnet and a ferrite permanent magnet, the rare earth permanent magnet being rectangular, the rare earth permanent magnet being quadrilateral, the ferrite permanent magnet having a radial inner side adjacent to a shaft hole, the rare earth permanent magnet being located on a radial outer side of the ferrite permanent magnet and being in contact connection with the radial outer side, the rare earth permanent magnet and the ferrite permanent magnet being symmetrical about the corresponding magnetic steel slot center line.

[0006] Preferably, the circumferential width of the rare earth permanent magnet is La, the circumferential width of the radial inner side of the ferrite permanent magnet is Lbs, and the circumferential width of the radial outer side of the ferrite permanent magnet is Lbl, 0.25≤La / ((Lbs+Lbl) / 2)≤0.55.

[0007] Preferably, the radial thickness of the rare earth permanent magnet is Ka, the radial thickness of the ferrite permanent magnet is Kb, 0.3≤Ka / Kb≤0.7; and / or, the radial thickness of the ferrite permanent magnet is Kb, the radius of the rotor core is R, 0.6≤Kb / R≤0.8.

[0008] Preferably, the tangential motor further comprises a stator assembly, the radial thickness of the rotor-stator air gap formed after the rotor assembly and the stator assembly are assembled is g, the magnetic steel slot is a semi-closed slot, the slot opening width of the magnetic steel slot is Lc, Lc>6g.

[0009] Preferably, the stator core in the stator assembly has a plurality of stator teeth, the circumferential width of the stator teeth is Bt, the opening angle formed between any two adjacent ferrite permanent magnets is θ, 3Kb×π×sinθ=10Bt.

[0010] Preferably, the stator assembly comprises a winding, the winding is an aluminum enameled wire; and / or, the stator core has 12 stator slots, the number of magnetic poles is 10 or 8.

[0011] Preferably, the stator core is one of a split structure, a thin bridge connection structure, and a chain connection structure.

[0012] Preferably, the rotor core comprises a plurality of rotor core sub-bodies.

[0013] Preferably, the plurality of rotor core sub-bodies are formed into an integral body by injection molding, or the plurality of rotor core sub-bodies are formed into an integral body by a connecting end plate at an axial end of the rotor core.

[0014] The application further provides a compressor comprising the tangential motor.

[0015] The application further provides an air conditioner comprising the compressor.

[0016] The tangential motor, the compressor, and the air conditioner provided by the application use the rare earth permanent magnet and the ferrite permanent magnet to jointly form a motor magnetic field, effectively preventing the high cost caused by the use of the rare earth permanent magnet alone and the relatively low performance of the motor caused by the use of the ferrite permanent magnet alone, so that the tangential motor of the application has relatively low manufacturing cost while ensuring relatively high motor performance. On the other hand, the rare earth permanent magnet is arranged outside the ferrite permanent magnet in the application, which can effectively utilize the high coercivity characteristic of the rare earth permanent magnet, guarantee the anti-demagnetization ability of the permanent magnet motor, and use a whole ferrite permanent magnet arranged near the shaft hole side to make the magnetization easy to saturate and reduce the magnetic leakage phenomenon, thereby improving the motor efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 Fig. 1 is a schematic diagram of the internal structure of a tangential motor according to an embodiment of the present application (radial section) ;

[0018] Figure 2 Fig. 2 is a schematic diagram of the partial structure of the tangential motor according to the embodiment of the present application; Figure 1 Fig. 3 is an enlarged schematic diagram of the partial structure of the tangential motor according to the embodiment of the present application;

[0019] Figure 3 Fig. 4 is a schematic diagram of the structure of the tangential motor according to the embodiment of the present application; Figure 1 Fig. 5 is a schematic diagram of the structure of the tangential motor according to the embodiment of the present application;

[0020] Figure 4 Fig. 6 is a comparison of the motor efficiency of the motor according to the technical solution of the present application and the motor in the prior art;

[0021] Figure 5 Fig. 7 is a comparison of the output torque of the motor according to the technical solution of the present application and the motor in the prior art.

[0022] The reference signs are as follows:

[0023] 1, rotor assembly; 11, rotor core; 111, shaft hole; 112, rotor core part; 113, connecting end plate; 121, rare earth permanent magnet; 122, ferrite permanent magnet; 2, stator assembly; 21, stator tooth; 22, winding; 23, stator core part. DETAILED DESCRIPTION

[0024] For reference, Figures 1 to 5As shown, according to the embodiment of the present application, a tangential motor is provided, comprising a rotor assembly 1 and a stator assembly 2, the stator assembly 2 is sleeved on the outer periphery of the rotor assembly 1 and a rotor-stator air gap is formed between the two, the rotor assembly 1 comprises a rotor core 11, the rotor core 11 has a plurality of magnetic poles, each of the magnetic poles is internally configured with a magnetic steel slot, the magnetic steel slot is internally provided with a rare earth permanent magnet 121 (such as a rare earth neodymium-iron-boron permanent magnet), a ferrite permanent magnet 122, in the projection of any radial plane of the rotor core 11, the rare earth permanent magnet 121 is rectangular, the ferrite permanent magnet 122 is quadrilateral, the ferrite permanent magnet 122 has a radial inner side adjacent to the shaft hole 111, the rare earth permanent magnet 121 is on the radial outer side of the ferrite permanent magnet 122 and is in contact connection with the radial outer side, the rare earth permanent magnet 121 and the ferrite permanent magnet 122 are both symmetrical about the corresponding magnetic steel slot center line. In this technical solution, the rare earth permanent magnet 121 and the ferrite permanent magnet 122 are used to jointly form a motor magnetic field, effectively preventing the high cost caused by the use of a rare earth permanent magnet 121 alone and the relatively low motor performance caused by the use of a ferrite permanent magnet 122 alone, so that the tangential motor of the present application has relatively low manufacturing cost while ensuring relatively optimal motor performance. On the other hand, the rare earth permanent magnet 121 is arranged on the outer side of the ferrite permanent magnet 122 in the present application, which can effectively utilize the high coercive force characteristics of the rare earth permanent magnet 121 to ensure the anti-demagnetization ability of the permanent magnet motor, and the use of a whole ferrite permanent magnet 122 close to the shaft hole 111 side makes it easy to saturate and reduce the magnetic leakage phenomenon, thereby improving the motor efficiency.

[0025] In some embodiments, the circumferential width of the rare earth permanent magnet 121 is La, the circumferential width of the radially inner side of the ferrite permanent magnet 122 is Lbs, the circumferential width of the radially outer side of the ferrite permanent magnet 122 is Lbl, and 0.25≤La / ((Lbs+Lbl) / 2)≤0.55. In this technical solution, the circumferential width of the rare earth permanent magnet 121 and the ferrite permanent magnet 122 is limited, which can ensure the performance of the motor and prevent the rare earth permanent magnet 121 from demagnetizing the ferrite permanent magnet 122. Specifically, if the ratio is less than 0.25, the average thickness of the magnetization direction of the ferrite permanent magnet 122 will be larger, the electromagnetic force of the motor will increase under the premise of ensuring the performance, the noise will be poor, and the layout of the ferrite permanent magnet 122 cannot meet the requirement of the preset pole number (for example, 10 poles); if the ratio is greater than 0.55, the thickness of the magnetization direction of the rare earth permanent magnet 121 is too large, which can cause the rare earth permanent magnet 121 to demagnetize the ferrite permanent magnet 122, and the performance of the motor is greatly reduced. For example, in a specific embodiment, the ferrite permanent magnet 122 is isosceles trapezoidal, and the long base of the isosceles trapezoid is the radially outer side of the ferrite permanent magnet 122, and the short base of the isosceles trapezoid is the radially inner side of the ferrite permanent magnet 122. In this way, the ferrite permanent magnet 122 has an outer large and inner small structure, which effectively improves the demagnetization of the rare earth permanent magnet 122 to the ferrite permanent magnet 122.

[0026] Further, the radial thickness of the rare earth permanent magnet 121 is Ka, the radial thickness of the ferrite permanent magnet 122 is Kb, and 0.3≤Ka / Kb≤0.7. If the ratio exceeds 0.7, Ka is too large, the use amount of the rare earth permanent magnet 121 increases under the premise of ensuring the performance and noise, and the cost increases. If the ratio exceeds 0.3, Ka is too small, the magnetic flux of the motor is small, and the performance is reduced. Based on the same reason, preferably, the radius of the rotor core 11 is R, and 0.6≤Kb / R≤0.8. Thus, the use amount of the rare earth permanent magnet 121 and the ferrite permanent magnet 122 is more reasonable, which can ensure the magnetic performance and the lowest cost.

[0027] Preferably, the tangential motor further comprises a stator assembly 2, and the radial thickness of the stator-rotor air gap formed after the rotor assembly 1 and the stator assembly 2 are assembled is g. The magnetic steel slot is a semi-closed slot, and the slot opening width of the magnetic steel slot is Lc, and Lc>6g. This can prevent the motor from having too large a cogging torque and too large a starting current, which affects the starting performance of the motor.

[0028] Preferably, the stator core in the stator assembly 2 has a plurality of stator teeth 21, the circumferential width of the stator teeth 21 is Bt, the opening angle formed between any two adjacent ferrite permanent magnets 122 is θ, and 3Kb x π x sinθ = 10Bt. In this technical solution, the three variables θ, Bt and Kb directly affect the air gap flux of the motor. For example, if θ is large, the air gap flux will be a short and fat sine wave, and if θ is too small, the air gap flux will be a tall and thin sine wave. When the three variables satisfy the relationship in this technical solution, the air gap flux is best and closest to a sine wave.

[0029] In some embodiments, the stator assembly 2 includes windings 22, which are aluminum enameled wires. It has been proven that the use of aluminum enameled wires instead of copper enameled wires in the prior art can save more than 20% of material costs.

[0030] The stator core has 12 stator slots, and the number of magnetic poles is 10 or 8, that is, this technical solution is especially suitable for 12-slot 10-pole or 12-slot 8-pole motors.

[0031] For reference, Figure 4 and Figure 5 As shown, by using the motor of the technical solution of the present application, the magnetic concentration effect of the tangential structure permanent magnet motor can be effectively increased by mixing the permanent magnet ratio and optimizing the design of the permanent magnet aspect ratio, the air gap flux is improved by 30%, and the efficiency of the tangential compressor motor of the present application is improved by more than 1% compared with the traditional radial permanent magnet synchronous motor, and the output torque is improved by more than 4.6%.

[0032] In some embodiments, the stator core is one of a segmented structure, a thin bridge connection structure, and a chain connection structure, for example Figure 1 The stator core is a segmented structure, which includes a plurality of stator core segments 23. This structure facilitates the winding of the windings 22. Further, the rotor core 11 includes a plurality of rotor core segments 112, which are formed integrally by injection molding or through a connection end plate 113 at the axial end of the rotor core 11. Specifically, as shown in Figure 1 As shown, the rotor core segments 112 are 10, each of the rotor core segments 112 is provided with a rivet hole, in assembly, the positions of the 10 rotor core segments 112 are fixed by a positioning clamp, and the rare earth permanent magnets 121 and the ferrite permanent magnets 122 are inserted at the same time, the permanent magnet baffles (i.e. the connection end plate 113) at both ends of the rotor core 11 are installed, and then the two ends are riveted by rivets, and if there are balance blocks and other accessories, they are riveted at the same time, and are assembled together; or an injection molding process is used to pack and form the 10 rotor core segments 112, the rare earth permanent magnets 121 and the ferrite permanent magnets 122, and then the permanent magnet baffles and balance blocks and other accessories are riveted.

[0033] The embodiment of the present application further provides a compressor comprising the above tangential motor.

[0034] The embodiment of the present application further provides an air conditioner comprising the above compressor.

[0035] Those skilled in the art can easily understand that the above advantageous modes can be freely combined and superposed without conflict.

[0036] The above merely describes the preferred embodiments of the present application, but should not be used to limit the present application. Any modification, equivalent replacement and improvement within the spirit and principle of the present application should be included in the protection scope of the present application. The above merely describes the preferred embodiments of the present application, but should not be used to limit the present application. Any modification, equivalent replacement and improvement within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A tangential motor, characterized in that, The rotor assembly (1) includes a rotor core (11) having multiple magnetic poles. Each magnetic pole has a magnetic slot, and rare earth permanent magnets (121) and ferrite permanent magnets (122) are installed in the magnetic slot. Projected onto any radial plane of the rotor core (11), the rare earth permanent magnets (121) are rectangular, and the ferrite permanent magnets (122) are quadrilateral. The ferrite permanent magnets (122) have a radially inner side adjacent to the shaft hole (111), and the rare earth permanent magnets (121) are located on the radially outer side of the ferrite permanent magnets (122) and are in contact with the radially outer side. The magnets (122) are all symmetrical about the center line of the corresponding magnetic steel groove; the circumferential width of the rare earth permanent magnet (121) is La, the circumferential width of the radial inner side of the ferrite permanent magnet (122) is Lbs, the circumferential width of the radial outer side of the ferrite permanent magnet (122) is Lbl, 0.25≤La / ((Lbs+Lbl) / 2)≤0.55; the radial thickness of the ferrite permanent magnet (122) is Kb, the tangential motor also includes a stator assembly (2), the stator core in the stator assembly (2) has multiple stator teeth (21), the circumferential width of the stator teeth (21) is Bt, and the angle formed between any two adjacent ferrite permanent magnets (122) is θ. .

2. The tangential motor according to claim 1, characterized in that, The radial thickness of the rare earth permanent magnet (121) is Ka, 0.3≤Ka / Kb≤0.7; and / or the radius of the rotor core (11) is R, 0.6≤Kb / R≤0.

8.

3. The tangential motor according to claim 2, characterized in that, The radial thickness of the air gap between the rotor assembly (1) and the stator assembly (2) after assembly is g. The magnet slot is a semi-closed slot and the slot opening width of the magnet slot is Lc, where Lc > 6g.

4. The tangential motor according to claim 3, characterized in that, The stator assembly (2) includes a winding (22) made of aluminum enameled wire; and / or, the stator core has 12 stator slots and the number of magnetic poles is 10 or 8.

5. The tangential motor according to claim 3, characterized in that, The stator core is one of the following: a segmented structure, a thin-bridge connection structure, or a chain connection structure.

6. The tangential motor according to claim 1, characterized in that, The rotor core (11) includes multiple rotor core segments (112).

7. The tangential motor according to claim 6, characterized in that, Multiple rotor core components (112) are formed into one piece by injection molding, or multiple rotor core components (112) are formed into one piece by a connecting end plate (113) located at the axial end of the rotor core (11).

8. A compressor, comprising a motor, characterized in that, The motor is a tangential motor as described in any one of claims 1 to 7.

9. An air conditioner, comprising a compressor, characterized in that, The compressor is the compressor described in claim 8.

Images