A magnetic suspension motor structure for refrigeration

Abstract

The utility model relates to a kind of magnetic suspension motor structure for refrigeration, including motor shell, the motor stator and motor rotor being set in the inside of motor shell and being compatible, the left and right ends of motor rotor are respectively provided with magnetic suspension bearing module, motor shell is provided with the cooling circuit for being connected with refrigeration system;Magnetic suspension bearing module includes bearing mounting seat fixed in the inside of motor shell, position sensor is arranged in bearing mounting seat, radial magnetic suspension coil is arranged on the side of position sensor facing the side where motor stator is located, axial magnetic suspension coil is arranged on the side of position sensor facing away from the side where motor stator is located.The utility model combines magnetic suspension bearing module in smaller shell space, left and right sides magnetic suspension bearing achieve universality and interchangeability, further enhance assembly efficiency and reliability, reduce subsequent maintenance replacement cost;And improve the anti-interference ability of electrical system, to ensure that equipment long-term stable and reliable operation.

Description

Technical Field

[0001] This utility model relates to a magnetic levitation motor structure for refrigeration. Background Technology

[0002] In the field of refrigeration equipment (such as central air conditioning, industrial chillers, heat pump units, etc.), the motor, as the core power component driving the compressor's rotation, directly determines the overall performance of the refrigeration system through its operating efficiency, stability, and energy consumption. Traditional refrigeration motors mostly employ rolling bearings or sliding bearings for support. However, with the continuous increase in rotational speeds in current refrigeration applications, the traditional motor structure exhibits the following significant problems during operation: 1. High mechanical losses and energy consumption: Traditional motors have low efficiency; 2. Limited reliability and lifespan: Mechanical bearings require lubrication, and stable operation cannot be guaranteed with long-term use; 3. Vibration and noise issues are prominent: Mechanical friction and bearing clearance inevitably aggravate motor vibration during operation, making it difficult to meet the requirements of low noise and comfort in modern scenarios; 4. Poor high-speed adaptability. As refrigeration systems become smaller and have higher power density, the required motor speeds are gradually increasing, and traditional mechanical bearings are unable to withstand the demands of high-speed operation.

[0003] To address the aforementioned issues, magnetic levitation bearing technology has been introduced into the field of refrigeration motors. Due to the absence of bearing friction loss and the need for lubrication, magnetic levitation bearing technology can easily meet the demands of high-speed applications at tens of thousands of revolutions per minute. However, existing magnetic levitation motors for refrigeration still have room for improvement: on the one hand, the heat loss of some magnetic levitation motors is not well-suited to the heat dissipation requirements of the refrigeration system, leading to excessively high operating temperatures and affecting levitation stability; on the other hand, the levitation force adjustment precision of some structures is low, making them prone to shaft displacement fluctuations under fluctuating refrigeration conditions, increasing control complexity. Utility Model Content

[0004] This utility model addresses the problems existing in the prior art by providing a magnetic levitation motor structure for refrigeration that is reasonably designed, adaptable to refrigeration scenarios, and balances efficient heat dissipation and high stability.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a magnetic levitation motor structure for refrigeration, comprising a motor housing, a motor stator and a motor rotor disposed inside the motor housing and adapted to each other, wherein magnetic levitation bearing modules are respectively disposed at the left and right ends of the motor rotor, and the motor housing is provided with a cooling circuit for connection to a refrigeration system; the magnetic levitation bearing module includes a bearing mounting seat fixed inside the motor housing, wherein a position sensor is disposed in the bearing mounting seat, a radial magnetic levitation coil is disposed on the side of the position sensor facing the motor stator, and an axial magnetic levitation coil is disposed on the side of the position sensor facing away from the motor stator.

[0006] Furthermore, the cooling circuit includes a cooling channel disposed on the inner wall of the motor housing, the cooling channel corresponding to the position of the motor stator and facilitating the flow of liquid refrigerant, the right end of the cooling channel being connected to a connecting channel facilitating the flow of gaseous refrigerant formed after the liquid refrigerant vaporizes to the right end of the motor housing; the left end of the motor housing is provided with an output channel facilitating the output of gaseous refrigerant flowing from right to left inside the motor housing.

[0007] Furthermore, the cooling channel is spiral-shaped along the axial direction of the motor housing.

[0008] Furthermore, the lower part of the motor housing is provided with an input channel for connecting to the refrigeration system. The input channel is connected to the left end of the cooling channel, and the refrigeration system introduces external liquid refrigerant into the cooling channel through the input channel.

[0009] Furthermore, a pneumatic housing is provided at the left end of the motor housing, a volute is provided inside the pneumatic housing, and an impeller connected to the left end of the motor rotor is provided inside the volute; the output channel is provided at the upper end of the pneumatic housing, and the gaseous refrigerant output from the output channel is drawn into the impeller's intake port.

[0010] Furthermore, there is a left flow space between the volute and the magnetic levitation bearing module located on the left side to facilitate the flow of gaseous refrigerant. The left flow space is connected to the output channel, and the gaseous refrigerant passing through the magnetic levitation bearing module located on the left side enters the output channel through the left flow space.

[0011] Furthermore, the impeller is a closed impeller, and the middle part of the impeller is locked to the left end of the motor rotor by a locking screw and a locking nut.

[0012] Furthermore, a tail end cover is provided at the right end of the motor housing, and there is a right flow space between the tail end cover and the magnetic levitation bearing module located on the right side to facilitate the flow of gaseous refrigerant. The gaseous refrigerant output from the connecting channel enters the right flow space and passes through the magnetic levitation bearing module located on the right side.

[0013] Furthermore, auxiliary bearings are connected to the left and right ends of the motor rotor, and the auxiliary bearings are mounted on the magnetic levitation bearing module via bearing pressure plates.

[0014] Furthermore, the motor rotor is a surface-mounted permanent magnet motor rotor; the motor housing is made of aluminum-magnesium alloy casting; the motor housing and the motor stator are installed with an interference fit through heating.

[0015] Compared with the prior art, this utility model has the following advantages: The utility model has a reasonable design, combining a magnetic levitation bearing module in a small housing space. The magnetic levitation bearing module adopts a modular assembly design, assembling the coil and position sensor sequentially in the bearing mounting seat, making the left and right magnetic levitation bearings universal and interchangeable, further enhancing assembly efficiency and reliability, and reducing subsequent maintenance and replacement costs. The reasonable spatial structure and wiring harness layout further improve the anti-interference capability of the electrical system while reducing the size of the equipment, thereby ensuring the long-term stable and reliable operation of the equipment. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the front cross-sectional structure of an embodiment of the present invention; Figure 2 This is a schematic diagram of the cooling circuit according to an embodiment of the present invention; Figure 3 yes Figure 1 Enlarged diagram of point A in the diagram.

[0017] In the picture: 1-Motor housing; 2-Motor stator; 3-Motor rotor; 4-Magnetic levitation bearing module; 41-Bearing mounting base; 42-Axial magnetic levitation coil; 43-Position sensor; 44-Radial magnetic levitation coil; 5-Tail end cover; 6-Auxiliary bearing; 7-Bearing pressure plate; 8-Pneumatic housing; 9-Impeller; 10-Locking screw; 11-Locking nut; 12-Cooling channel; 13-Connecting channel; 14-Output channel; 15-Input channel; 16-Left side flow space; 17-Right side flow space; 18-Impeller intake port; 19-Volume. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0019] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0020] like Figures 1-3 As shown, this utility model discloses a magnetic levitation motor structure for refrigeration, designed to adapt to refrigeration scenarios while balancing efficient heat dissipation and high stability. It includes a motor housing 1, a motor stator 2 and a motor rotor 3 housed and fitted inside the motor housing 1. The motor stator 2 is installed inside the motor housing 1, and the motor rotor 3 penetrates the motor stator 2 in a left-right direction. Magnetic levitation bearing modules 4 are respectively provided at the left and right ends of the motor rotor 3. The magnetic levitation bearing modules 4 at both ends generate magnetic force, keeping the motor rotor 3 in a levitation state at all times. More specifically, the motor housing 1 is provided with a cooling circuit for connection to a refrigeration system. The magnetic levitation bearing module 4 includes a bearing mounting base 41 fixed inside the motor housing 1 by bolts. A position sensor 43 is provided inside the bearing mounting base 41. A radial magnetic levitation coil 44 is provided on the side of the position sensor 43 facing the motor stator 2, and an axial magnetic levitation coil 42 is provided on the side of the position sensor 43 facing away from the motor stator 2.

[0021] In this embodiment, the axial magnetic levitation coil 42, position sensor 43, and radial magnetic levitation coil 44 are fixed to the bearing mounting base 41 by thermal assembly, and are fitted onto the outside of the motor rotor. The magnetic levitation bearing module consists of a bearing mounting base, axial magnetic levitation coil, position sensor, and radial magnetic levitation coil; the identical magnetic levitation bearing modules on the left and right sides achieve universality and interchangeability, enhancing assembly efficiency and reliability, and reducing subsequent maintenance and replacement costs.

[0022] The working principle of this magnetic levitation motor is as follows: Magnetic force is generated by magnetic levitation bearing modules 4 installed at both ends, keeping the motor rotor 3 in a suspended state at all times. During motor operation, position sensors 43 on the magnetic levitation bearing modules 4 can detect changes in the rotor shaft position in real time and transmit the position signal to the bearing controller. The bearing controller converts the collected position signal into a control signal, controlling the current in the magnetic levitation coil, thereby driving the motor rotor 3 shaft back to its center position. During motor operation, regardless of whether the motor rotor is subjected to radial or axial loads, the rotor always remains in a stable equilibrium state, ensuring smooth motor operation.

[0023] In this embodiment, the cooling circuit includes a cooling channel 12 disposed on the inner wall of the motor housing 1. The cooling channel 12 corresponds to the position of the motor stator 2 and is a cooling channel 12 that facilitates the flow of liquid refrigerant. The liquid refrigerant flowing in the cooling channel 12 dissipates heat from the motor stator 2. After absorbing heat, the liquid refrigerant vaporizes. The right end of the cooling channel 12 is connected to a connecting channel 13, which facilitates the flow of gaseous refrigerant formed after the liquid refrigerant vaporizes from left to right to the right end of the motor housing 1. The left end of the motor housing 1 is provided with an output channel 14, which facilitates the output of gaseous refrigerant flowing from right to left inside the motor housing 1. During operation, the liquid refrigerant flowing in the cooling channel 12 dissipates heat from the motor stator 2. After absorbing heat, the liquid refrigerant vaporizes, and the vaporized refrigerant flows through the connecting channel 13 to the right end of the motor housing 1. Then, the gaseous refrigerant flows from right to left inside the motor housing 1, first passing through the magnetic levitation bearing module 4 located on the right, then through the motor stator 2 and the motor rotor 3, and finally through the magnetic levitation bearing module 4 located on the left, completing the cooling of the above components, and then being output from the output channel 14.

[0024] In this embodiment, the cooling channel 12 is spiral-shaped along the axial direction of the motor housing. By designing a spiral cooling channel, the flow path of the liquid refrigerant can be extended, facilitating sufficient heat absorption and vaporization, and improving the heat dissipation effect on the motor stator.

[0025] In this embodiment, the lower part of the motor housing 1 is provided with an input channel 15 for connecting to the refrigeration system. The input channel 15 is connected to the left end of the cooling channel 12. Utilizing the characteristics of the refrigeration cycle system, the refrigeration system introduces external liquid refrigerant into the cooling channel 12 through the input channel 15. The connecting channel is located at the lower part of the motor housing and extends along the axial direction of the motor housing.

[0026] In this embodiment, a pneumatic housing 8, integrally cast and machined, is provided at the left end of the motor housing 1. The pneumatic housing 8 is fixed to the motor housing 1 by bolts. The pneumatic housing 8 is provided with a volute 19, a diffuser channel, and other compression and refrigeration structures. An impeller 9 connected to the left end of the motor rotor 3 is provided inside the volute 19. The output channel 14 is provided at the upper end of the pneumatic housing 8 and extends along the axial direction of the pneumatic housing 8. The output port of the output channel 14 is located on the same side as the intake port 18 of the impeller. The gaseous refrigerant output by the output channel 14 is drawn into the intake port 18 of the impeller, so that the gaseous refrigerant re-enters the refrigeration system for circulation.

[0027] In this embodiment, the impeller 9 is a precision-cast closed impeller, which can achieve high-efficiency and high-performance airflow transmission. Furthermore, the middle part of the impeller 9 is locked to the left end of the motor rotor 3 via a locking screw 10 and a locking nut 11.

[0028] In this embodiment, there is a left flow space 16 between the volute 19 and the magnetic levitation bearing module 4 located on the left side to facilitate the flow of gaseous refrigerant. The left flow space 16 is connected to the output channel 14. The gaseous refrigerant passing through the magnetic levitation bearing module 4 located on the left side enters the output channel 14 through the left flow space 16.

[0029] In this embodiment, a tail end cover 5 is provided at the right end of the motor housing 1. The tail end cover 5 is fixed to the motor housing 1 by bolts to form a closed motor structure.

[0030] In this embodiment, there is a right flow space 17 between the tail cap 5 and the magnetic levitation bearing module 4 located on the right side to facilitate the flow of gaseous refrigerant. The gaseous refrigerant output from the connecting channel 13 enters the right flow space 17 and passes through the magnetic levitation bearing module 4 located on the right side.

[0031] In this embodiment, auxiliary bearings 6 are connected to the left and right ends of the motor rotor 3, allowing the motor rotor 3 to rotate smoothly on the auxiliary bearings 6. The auxiliary bearings 6 are mounted on the magnetic levitation bearing module 4 via bearing pressure plates 7. Specifically, the auxiliary bearings 6 are located inside the axial magnetic levitation coil 42, and the bearing pressure plates 7 are mounted on the top of the auxiliary bearings 6. The bearing pressure plates 7 are bolted to the axial magnetic levitation coil 42, thus enabling the auxiliary bearings to be mounted on the magnetic levitation bearing module 4. The bearing pressure plates 7 keep the auxiliary bearings 6 stable during motor rotor operation, preventing positional changes due to vibration. Preferably, the auxiliary bearings 6 are high-speed ceramic ball bearings. The auxiliary bearings 6 are mounted on the magnetic levitation bearing modules 4 on both sides, serving to support the motor rotor when the motor is not running and can withstand certain axial impact loads. Furthermore, if the magnetic levitation bearings fail during high-speed rotation, the auxiliary bearings 6 can withstand at least 20 high-speed drop conditions.

[0032] In this embodiment, the motor rotor 3 is a surface-mounted permanent magnet motor rotor, and the surface roughness requirement is 0.8μm to ensure high-speed friction performance.

[0033] In this embodiment, the motor housing 1 is made of aluminum-magnesium alloy casting, with internal machined surfaces and threaded holes for mounting the motor stator, magnetic levitation bearing module, etc. The cooling channels and connecting channels inside the motor housing are cast together with the motor housing.

[0034] In this embodiment, the motor housing 1 and the motor stator 2 are installed with an interference fit through heating. Specifically, during installation, the magnetic levitation bearing module 4 on the right side is bolted into the motor housing 1, and then the right end of the motor rotor 3 passes through the motor stator 2 and is fixed to the magnetic levitation bearing module 4 on the right side. The magnetic levitation bearing module 4 on the left side passes through the left end of the motor rotor 3 and is bolted to the motor housing 1.

[0035] like Figure 2 As shown, the cooling circuit is illustrated as follows: A spiral cooling channel 12 is provided on the motor housing 1. Liquid refrigerant circulating in the refrigeration system enters the spiral cooling channel 12 from the lower part of the motor housing 1 (i.e., the input channel 13) and cools the motor stator 2 through the spiral cooling channel 12. The liquid refrigerant absorbs heat and vaporizes within the spiral cooling channel 12, entering the interior of the right side of the motor housing 1. The gaseous refrigerant passes sequentially from inside the motor housing 1 through the magnetic levitation bearing module 4 on the right side, the motor stator 2, the motor rotor 3, and the magnetic levitation bearing module 4 on the left side, completing the cooling of these components. Finally, the gaseous refrigerant returns to the impeller 9 side through the output channel 14 within the pneumatic housing 8 and re-enters the refrigeration system through the impeller's intake port 18. The cooling channel, connecting channel, output channel, and the space inside the motor housing form a cooling flow space, achieving a specialized refrigerant compatibility design. This allows refrigerant to be introduced into the motor for cooling, fully utilizing the refrigeration system circulation system, effectively ensuring the motor's heat dissipation requirements while increasing overall efficiency.

[0036] The advantages of this utility model are: (1) The motor operates reliably and with high stability. The magnetic levitation bearing module is combined with the high-speed motor structure in a relatively small housing space. The magnetic levitation bearing adopts a modular assembly design, with the coil and position sensor assembled sequentially in a dedicated bearing mounting base. This makes the left and right magnetic levitation bearings universal and interchangeable, further enhancing assembly efficiency and reliability, and reducing subsequent maintenance and replacement costs. The reasonable spatial structure and wiring harness layout further improve the anti-interference capability of the electrical system while reducing the size of the equipment, thereby ensuring the long-term stable and reliable operation of the equipment.

[0037] (2) The motor uses a special refrigerant compatibility design, which allows the refrigerant to be introduced into the motor for cooling, making full use of the refrigeration system circulation system, effectively ensuring the motor's heat dissipation requirements while increasing overall efficiency.

[0038] If this utility model discloses or relates to mutually fixedly connected parts or structural components, then, unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured using a casting process) (except where it is obviously impossible to use an integral forming process).

[0039] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in this utility model above include states or shapes that are similar to, close to, or approximate with them.

[0040] Any component provided by this utility model can be assembled from multiple individual components, or it can be a single component manufactured by a one-piece molding process.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A magnetic levitation motor structure for refrigeration, comprising a motor housing (1), a motor stator (2) and a motor rotor (3) disposed inside the motor housing (1) and adapted thereto, wherein magnetic levitation bearing modules (4) are respectively disposed at the left and right ends of the motor rotor (3), characterized in that: The motor housing (1) is provided with a cooling circuit for connection to the refrigeration system; the magnetic levitation bearing module (4) includes a bearing mounting seat (41) fixed inside the motor housing (1), a position sensor (43) is provided inside the bearing mounting seat (41), a radial magnetic levitation coil (44) is provided on the side of the position sensor (43) facing the motor stator (2), and an axial magnetic levitation coil (42) is provided on the side of the position sensor (43) facing away from the motor stator (2).

2. The magnetic levitation motor structure for refrigeration according to claim 1, characterized in that: The cooling circuit includes a cooling channel (12) disposed on the inner wall of the motor housing (1), the cooling channel (12) being positioned corresponding to the motor stator (2) and facilitating the flow of liquid refrigerant, the right end of the cooling channel (12) being connected to a connecting channel (13) facilitating the flow of gaseous refrigerant formed after the liquid refrigerant vaporizes to the right end of the motor housing (1); the left end of the motor housing (1) is provided with an output channel (14), the output channel (14) facilitating the output of gaseous refrigerant flowing from right to left inside the motor housing (1).

3. The magnetic levitation motor structure for refrigeration according to claim 2, characterized in that: The cooling channel (12) is spiral-shaped along the axial direction of the motor housing (1).

4. A magnetic levitation motor structure for refrigeration according to claim 2 or 3, characterized in that: The lower part of the motor housing (1) is provided with an input channel (15) for connecting to the refrigeration system. The input channel (15) is connected to the left end of the cooling channel (12). The refrigeration system introduces external liquid refrigerant into the cooling channel (12) through the input channel (15).

5. The magnetic levitation motor structure for refrigeration according to claim 2, characterized in that: A pneumatic housing (8) is provided at the left end of the motor housing (1), and a volute (19) is provided inside the pneumatic housing (8). An impeller (9) connected to the left end of the motor rotor (3) is provided inside the volute (19). The output channel (14) is provided at the upper end of the pneumatic housing (8), and the gaseous refrigerant output from the output channel (14) is drawn in by the air intake (18) of the impeller.

6. The magnetic levitation motor structure for refrigeration according to claim 5, characterized in that: The volute (19) and the magnetic levitation bearing module (4) located on the left side have a left flow space (16) to facilitate the flow of gaseous refrigerant. The left flow space (16) is connected to the output channel (14). The gaseous refrigerant passing through the magnetic levitation bearing module (4) located on the left side enters the output channel (14) through the left flow space.

7. The magnetic levitation motor structure for refrigeration according to claim 5, characterized in that: The impeller (9) is a closed impeller, and the middle part of the impeller (9) is locked to the left end of the motor rotor (3) by the locking screw (10) and the locking nut (11).

8. The magnetic levitation motor structure for refrigeration according to claim 2, characterized in that: The motor housing (1) is provided with a tail end cover (5) at the right end. There is a right flow space (17) between the tail end cover (5) and the magnetic levitation bearing module (4) located on the right side to facilitate the flow of gaseous refrigerant. The gaseous refrigerant output from the connecting channel (13) enters the right flow space (17) and passes through the magnetic levitation bearing module (4) located on the right side.

9. The magnetic levitation motor structure for refrigeration according to claim 1, characterized in that: The left and right ends of the motor rotor (3) are respectively connected to auxiliary bearings (6), and the auxiliary bearings (6) are installed on the magnetic levitation bearing module (4) through bearing pressure plate (7).

10. The magnetic levitation motor structure for refrigeration according to claim 1, characterized in that: The motor rotor (3) is a surface-mounted permanent magnet motor rotor; the motor housing (1) is made of aluminum-magnesium alloy casting; the motor housing (1) and the motor stator (2) are installed by interference fit through heating.

Images