Magnetic suspension compressor assembly and control method thereof

Abstract

The invention provides a magnetic suspension compressor assembly and a control method thereof.The magnetic suspension compressor assembly comprises a magnetic suspension compressor and a bypass flow path, and the magnetic suspension compressor is provided with an air suction port and an exhaust port; a to-be-compressed refrigerant is introduced into the magnetic suspension compressor through an air suction port, the compressed refrigerant is discharged through an exhaust port, and the air suction port can be opened or closed; the bypass flow path is communicated between the upstream side of the air suction port and the exhaust port, so that when the air suction port is closed, the magnetic suspension compressor assembly can guide a refrigerant flowing to the air suction port to the exhaust port through the bypass flow path; the bypass flow path can be opened or closed. According to the technical scheme, the rotor of the magnetic suspension compressor can be prevented from being impacted by airflow external force in the starting or shutdown stage, so that the magnetic suspension compressor can be normally started, and the rotor can safely descend at zero rotating speed when the magnetic suspension compressor is shut down.

Description

Technical Field

[0001] The invention belongs to the technical field of magnetic suspension compressors, and in particular relates to a magnetic suspension compressor component and a control method thereof. Background Art

[0002] The magnetic levitation compressor uses magnetic levitation bearings to allow the rotor to suspend frictionlessly in a given space for rotation. The steps for starting a magnetic levitation compressor are generally to control the rotor suspension first. After the rotor is suspended, the inverter controls the rotor to rotate, and the magnetic levitation compressor starts working. However, in actual applications, due to the oil-free, contact-free and friction-free characteristics of the magnetic levitation compressor system, after the rotor is suspended, the impeller at the front end of the rotor is easily driven to rotate by the external force of the airflow. For example, in a system equipped with a fluorine pump, the fluorine pump will be turned on when the system is turned on to allow the refrigerant to flow and circulate in the system. At this time, the rotor is suspended. If the circulating refrigerant impacts the impeller, the impeller will drive the rotor to rotate. This state is very unfavorable for the inverter to control the suspension and rotation of the rotor. First, because the inverter controls the rotation of the rotor and requires starting from 0 speed, if there is an uncertain initial speed, it will cause control disorder, motor winding overcurrent, startup failure and other faults, and in severe cases, the winding coil and components will be damaged; second, the rotor is impacted by the external force of the airflow at the beginning of the suspension stage, which is easy to cause suspension instability, resulting in suspension failure and failure to start normally. In addition, during the shutdown process, the rotor needs to be controlled to stop floating. During this process, if there is air flow impact that causes the rotor to rotate, it is easy to cause the rotor to become unstable or the rotor to rub against the protective bearing, resulting in a shortened life of the protective bearing. Summary of the invention

[0003] Therefore, the present invention provides a magnetic levitation compressor assembly and a control method thereof, the main technical problem to be solved is: how to reduce the impact of airflow external force on the rotor of the magnetic levitation compressor during startup or shutdown.

[0004] In order to solve the above problems, the present invention provides a magnetic levitation compressor assembly, which includes a magnetic levitation compressor and a bypass flow path, wherein the magnetic levitation compressor has an air intake port and an air discharge port, and the magnetic levitation compressor introduces a refrigerant to be compressed through the air intake port, and discharges the compressed refrigerant through the air discharge port;

[0005] Among them, the air intake port can be opened or closed; the bypass flow path is connected between the upstream side of the air intake port and the exhaust port, so that when the air intake port is closed, the magnetic levitation compressor assembly can guide the refrigerant flowing to the air intake port to the exhaust port through the bypass flow path; the bypass flow path can be opened or closed.

[0006] In some embodiments, the magnetic levitation compressor assembly further includes a first switch valve, which is disposed on a pipeline between an air inlet of the bypass flow path and the air intake port to control the opening or closing of the air intake port.

[0007] In some embodiments, a guide vane mechanism with controllable opening is provided at the air intake port, and the guide vane mechanism is used to control the opening or closing of the air intake port.

[0008] In some embodiments, the magnetic levitation compressor assembly further includes a second switch valve, which is disposed on the bypass flow path to control the opening or closing of the bypass flow path.

[0009] The present invention also provides a control method for the magnetic levitation compressor assembly described in any one of the above items:

[0010] When the magnetic levitation compressor is turned on, step S11 and step S12 are executed in sequence. Step S11 is: controlling the air intake port to be closed and the bypass flow path to be opened; step S12 is: controlling the rotor of the magnetic levitation compressor to be suspended;

[0011] And / or, when the magnetic levitation compressor is shut down, step S21 and step S22 are executed in sequence, step S21 is: controlling the air intake port to close and the bypass flow path to open; step S22 is: controlling the rotor of the magnetic levitation compressor to stop levitation.

[0012] In some embodiments, when the magnetic levitation compressor is turned on, step S13 and step S14 are executed in sequence after step S12, step S13 is: controlling the rotor of the magnetic levitation compressor to rotate to a target speed; step S14 is: controlling the air intake port to open and the bypass flow path to close.

[0013] In some embodiments, in step S13, a rotation instruction is sent to the frequency converter through the unit controller, so that the frequency converter controls the rotor of the magnetic levitation compressor to rotate to a target speed; wherein,

[0014] In step S12, the unit controller sends a suspension instruction to the bearing controller, so that the bearing controller controls the rotor of the magnetic levitation compressor to suspend; wherein, after the unit controller sends the suspension instruction to the bearing controller in step S12, the unit controller sends a rotation instruction to the frequency converter after a delay time a in step S13;

[0015] And / or, in step S14, the unit controller controls the air intake port to open and the bypass flow path to close; wherein, after the unit controller sends a rotation command to the inverter in step S13, the air intake port is controlled to open and the bypass flow path is controlled to close in step S14 after a delay time b.

[0016] In some embodiments, when the magnetic levitation compressor is shut down, step S20 is further executed before step S21, and step S20 is: controlling the rotor of the magnetic levitation compressor to stop rotating.

[0017] In some embodiments, in step S21, the air intake port is controlled to be closed and the bypass flow path is opened by the unit controller; in step S22, a suspension stop instruction is sent to the bearing controller by the unit controller, so that the bearing controller controls the rotor of the magnetic levitation compressor to stop suspension; wherein, after the unit controller controls the air intake port to be closed and the bypass flow path to be opened in step S21, the suspension stop instruction is sent to the bearing controller again in step S22 after a delay time c.

[0018] The magnetic suspension compressor assembly and control method thereof provided by the present invention have the following beneficial effects:

[0019] When the magnetic levitation compressor of the present invention is turned on, the air intake port can be closed first to prevent the airflow from entering the magnetic levitation compressor from the air intake port and impacting the rotor to cause the rotor to rotate, thereby preventing the rotor from being impacted by the external force of the airflow when the machine is turned on, ensuring that the rotor can be suspended and rotated from zero speed when the machine is turned on, so as to ensure that the magnetic levitation compressor can be started normally. When the magnetic levitation compressor is turned off, the air intake port can also be closed to ensure that the rotor is not affected by the impact of the airflow before it stops suspending, so as to achieve a safe landing of the rotor at zero speed. In addition, when the magnetic levitation compressor is turned on or off, the bypass flow path can be opened to ensure that the airflow of the unit system can circulate without blockage before starting and after shutting down while the rotor is suspended, rotated and stopped from zero speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. The drawings described below are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0021] Figure 1 It is a structural schematic diagram of the magnetic suspension compressor assembly of the present invention;

[0022] Figure 2 It is a hardware circuit diagram of the magnetic suspension compressor assembly of the present invention;

[0023] Figure 3 It is a control flow chart of the magnetic suspension compressor of the magnetic suspension compressor assembly of the present invention when it is turned on;

[0024] Figure 4It is a control flow chart of the magnetic suspension compressor of the magnetic suspension compressor assembly of the present invention when the magnetic suspension compressor is shut down;

[0025] Figure 5 It is the startup control flow chart of the unit controller;

[0026] Figure 6 It is the shutdown control flow chart of the unit controller.

[0027] The accompanying drawings are marked as follows:

[0028] 1. Magnetic levitation compressor; 2. Bypass flow path; 3. First switch valve; 4. Second switch valve; 5. Unit controller; 6. Bearing controller; 7. Frequency converter; 21. Air inlet of bypass flow path; 101. Air intake port; 102. Exhaust port. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0031] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0032] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0033] See also Figure 1 As shown, according to an embodiment of the present invention, a magnetic levitation compressor assembly is provided, which includes a magnetic levitation compressor 1 and a bypass flow path 2, wherein the magnetic levitation compressor 1 has an air intake port 101 and an air discharge port 102. The magnetic levitation compressor 1 introduces a refrigerant to be compressed through the air intake port 101, and discharges the compressed refrigerant through the air discharge port 102.

[0034] The air intake port 101 can be opened or closed. The bypass flow path 2 is connected between the upstream side of the air intake port 101 and the exhaust port 102, so that when the air intake port 101 is closed, the magnetic levitation compressor assembly can guide the refrigerant flowing to the air intake port 101 to the exhaust port 102 through the bypass flow path 2. The bypass flow path 2 can be opened or closed.

[0035] In the above example, when the magnetic levitation compressor 1 is turned on, the air intake port 101 can be closed first to prevent the airflow from entering the magnetic levitation compressor 1 from the air intake port 101 and impacting the rotor to cause the rotor to rotate, thereby preventing the rotor from being impacted by the external force of the airflow when it is turned on, ensuring that the rotor can be suspended and rotated from a speed of 0 rpm when it is turned on, so that the magnetic levitation compressor 1 can be started normally. When the magnetic levitation compressor 1 is turned off, the air intake port 101 can also be closed to ensure that the rotor is not affected by the impact of the airflow before it stops suspending, so as to achieve a safe landing of the rotor at 0 rpm. In addition, when the magnetic levitation compressor 1 is turned on or off, the bypass flow path 2 can be opened to ensure that the airflow of the unit system can circulate without blockage before and after startup while achieving the suspension, rotation and suspension of the rotor from a speed of 0 rpm.

[0036] It should be noted that the magnetic levitation compressor 1 of the present invention also has a compression part, the air intake port 101 is used to introduce the refrigerant to be compressed into the compression part, the compression part is used to compress the refrigerant introduced by the air intake port 101, and the exhaust port 102 is used to discharge the refrigerant compressed by the compression part. The air intake port 101, the compression part and the exhaust port 102 form a compression flow path. The bypass flow path 2 and the compression flow path are parallel flow paths.

[0037] In order to realize the function that the air inlet 101 can be opened or closed, in the first example, Figure 1 As shown, the aforementioned magnetic levitation compressor assembly may further include a first switch valve 3. The first switch valve 3 may be disposed on a pipeline between the air inlet 21 of the bypass flow path and the air intake port 101 to control the opening or closing of the air intake port 101, and when the air intake port 101 is closed, the magnetic levitation compressor assembly may guide the refrigerant flowing to the air intake port 101 to the exhaust port 102 through the bypass flow path 2. The first switch valve 3 may be a solenoid valve or an electric valve such as an electric butterfly valve.

[0038] In the second example, the aforementioned air intake port 101 may be provided with a guide vane mechanism with a controllable opening, and the guide vane mechanism is used to control the opening or closing of the air intake port 101, and when the air intake port 101 is closed, the magnetic levitation compressor assembly can guide the refrigerant flowing to the air intake port 101 to the exhaust port 102 through the bypass flow path 2. The specific structure of the guide vane mechanism is prior art and will not be described in detail here.

[0039] It should be noted here that: if the air intake port 101 of the magnetic levitation compressor 1 is equipped with a guide vane mechanism with controllable opening, there is no need to install the aforementioned first switch valve 3. The guide vane mechanism can replace the aforementioned first switch valve 3 and play the same control role, and can both open or close the air intake port 101.

[0040] In some embodiments, Figure 1 As shown, the aforementioned magnetic levitation compressor assembly may further include a second switch valve 4, which is arranged on the bypass flow path 2 to control the opening or closing of the bypass flow path 2. The second switch valve 4 may be a solenoid valve or an electric valve such as an electric butterfly valve.

[0041] The present invention also provides a control method for the above-mentioned magnetic suspension compressor assembly. In some embodiments, Figure 3 As shown, when the magnetic levitation compressor 1 is turned on, step S11 and step S12 can be executed in sequence. Step S11 is: controlling the air intake port 101 to be closed and the bypass flow path 2 to be opened. Step S12 is: controlling the rotor of the magnetic levitation compressor 1 to be suspended.

[0042] In the above control method, when the magnetic levitation compressor 1 is started, before the rotor levitates, the suction port 101 is controlled to close and the bypass flow path 2 is opened first. This can prevent the air flow from entering the magnetic levitation compressor 1 through the suction port 101 and impacting the rotor before the rotor levitates, causing the rotor to rotate. At the same time, it ensures that the air flow can flow through the bypass flow path 2 without affecting the normal operation of the unit's fluorine pump system, enabling the refrigerant to flow and circulate normally in the system.

[0043] In some embodiments, as Figure 3 shown, when the magnetic levitation compressor 1 is started, after step S12, steps S13 and S14 are sequentially executed. Among them, step S13 is: controlling the rotor of the magnetic levitation compressor 1 to rotate to the target speed. After step S13, at this time, the rotor has a certain speed and is not easily affected by the air flow impact before startup. Among them, step S14 is: controlling the suction port 101 to open and the bypass flow path 2 to close. After step S14, it can be ensured that the refrigerant air flow enters from the suction port 101 and is discharged from the exhaust port 102, and the magnetic levitation compressor 1 of the present invention completes startup and can operate normally under load.

[0044] In some embodiments, as Figure 2 shown, in the foregoing step S12, a levitation instruction can be sent from the unit controller 5 to the bearing controller 6 to enable the bearing controller 6 to control the rotor of the magnetic levitation compressor 1 to levitate. In the foregoing step S13, a rotation instruction can be sent from the unit controller 5 to the frequency converter 7 to enable the frequency converter 7 to control the rotor of the magnetic levitation compressor 1 to rotate to the target speed.

[0045] Among them, after the unit controller 5 sends a levitation instruction to the bearing controller 6 in step S12, after a delay time a, a rotation instruction is sent to the frequency converter 7 in step S13. Such a design is mainly to ensure that the rotor can complete levitation within the time a before the frequency converter 7 controls the rotor to rotate, avoiding the rotor being driven to rotate by the frequency converter 7 before it has completed levitation.

[0046] In some embodiments, the target speed can be n satisfying: 50 rpm < n < 500 rpm. The above time a satisfies: 0 < a < 30 seconds.

[0047] In some embodiments, as Figure 2 shown, in the foregoing step S14, the unit controller 5 can be used to control the suction port 101 to open and the bypass flow path 2 to close. Among them, after the unit controller 5 sends a rotation instruction to the frequency converter 7 in step S13, after a delay time b, in step S14, the suction port 101 is controlled to open and the bypass flow path 2 is closed. Such a design is mainly to enable the rotor to reach the target speed within the time b before the suction port 101 opens. At this time, the rotor has a certain speed and is not easily affected by the air flow impact before startup.

[0048] In some embodiments, the above-mentioned time b satisfies: 5 seconds < b < 30 seconds.

[0049] In some embodiments, as Figure 4 shown, when the magnetic levitation compressor 1 shuts down, steps S21 and S22 can be sequentially executed. Step S21 is: controlling the suction port 101 to close and the bypass flow path 2 to open. Step S22 is: controlling the rotor of the magnetic levitation compressor 1 to stop levitating.

[0050] In the above control method, when the magnetic levitation compressor 1 shuts down, before the rotor stops levitating, first control the suction port 101 to close and the bypass flow path 2 to open, so as to ensure that the rotor is not affected by the airflow impact and does not rotate before stopping levitating; at the same time, ensure that the airflow can flow through the bypass flow path 2, so that the airflow in the unit system can circulate without blockage after shutdown.

[0051] In some embodiments, as Figure 4 shown, when the magnetic levitation compressor 1 shuts down, step S20 is also executed before step S21. Step S20 is: controlling the rotor of the magnetic levitation compressor 1 to stop rotating. Among them, the rotor stops rotating before stopping levitating, avoiding the rotor rotating and rubbing against the protective bearing when stopping levitating, which affects the service life.

[0052] In some embodiments, as Figure 2 shown, in step S21, the unit controller 5 can control the suction port 101 to close and the bypass flow path 2 to open. In step S22, the unit controller 5 can send a stop levitation instruction to the bearing controller 6, so that the bearing controller 6 controls the rotor of the magnetic levitation compressor 1 to stop levitating. Among them, after the unit controller 5 controls the suction port 101 to close and the bypass flow path 2 to open in step S21, the unit controller 5 delays for a time c and then sends a stop levitation instruction to the bearing controller 6 in step S22. Such a design is mainly to enable the rotor to stop rotating within the time c (i.e., the rotational speed is 0 rpm) before the suction port 101 opens, avoiding the rotor rotating and rubbing against the protective bearing when stopping levitating, which affects the service life.

[0053] In some embodiments, the above-mentioned time c satisfies: 10 seconds < c < 60 seconds. In addition, after receiving the stop levitation instruction, the bearing controller 6 controls the rotor to stop levitating, and delays for a time d to wait for the rotor to stop levitating. The rotor safely lands on the protective bearing, and the shutdown is completed. Among them, the above-mentioned time d satisfies: 0 < d < 30 seconds.

[0054] It should be noted here that in some embodiments, the aforementioned suction port 101 is opened or closed by the first switching valve 3, and the aforementioned bypass flow path 2 is opened or closed by the second switching valve 4. Among them, when both the first switching valve 3 and the second switching valve 4 are solenoid valves, the unit controller 5 controls the opening or closing of the suction port 101 by controlling the first switching valve 3, and the unit controller 5 controls the opening or closing of the bypass flow path 2 by controlling the second switching valve 4.

[0055] The aforementioned bearing controller 6 can be the bearing controller自带的 of the magnetic levitation compressor 1. Similarly, the aforementioned frequency converter 7 can be the frequency converter自带的 of the magnetic levitation compressor 1.

[0056] For ease of understanding, the present invention provides a specific control method for a magnetic levitation compressor assembly. Combining Figure 5 with the start-up control flow chart of the unit controller 5 in, when the unit controller 5 receives the compressor start-up instruction from the user, the next step is to control the second switching valve 4 on the bypass flow path 2 to open, and control the first switching valve 3 at the suction port 101 to close, preventing the air flow from entering the magnetic levitation compressor 1 from the suction port 101 and causing an impact on the rotor and rotation. At the same time, ensure that the air flow can flow through the bypass flow path 2 without affecting the normal operation of the unit's fluorine pump system. Among them, the function of the fluorine pump system is to circulate the refrigerant in the unit. For example, in a system equipped with a fluorine pump, the fluorine pump will be started first before the compressor is started to make the refrigerant flow and circulate in the system. The fluorine pump is widely used in central air conditioners. The next step is for the unit controller 5 to send a suspension instruction to the bearing controller 6 of the magnetic levitation compressor 1. After receiving the instruction, the bearing controller 6 controls the rotor to levitate and delays for a (0 < a < 30) seconds to wait for the rotor to complete levitation; the next step is for the unit controller 5 to send a rotation instruction to the frequency converter 7. After receiving the instruction, the frequency converter 7 controls the compressor rotor to rotate from 0 rpm to the target speed. The target speed is n, 50 rpm < n < 500 rpm, and delays for b (5 < b < 30) seconds to wait for the compressor rotor to reach the target speed. At this time, the compressor rotor has a certain speed and is not easily affected by the air flow impact before starting; the next step is for the unit controller 5 to control the first switching valve 3 at the suction port 101 to open, and control the second switching valve 4 on the bypass flow path 2 to close, ensuring that the refrigerant air flow enters from the suction port 101 and is discharged from the exhaust port 102, and the compressor completes the start-up and can operate normally under load.

[0057] Combining Figure 6Shutdown control flowchart of the middle unit controller 5. When the unit controller 5 receives the user's compressor shutdown instruction, in the next step, the unit controller 5 sends a stop rotation instruction to the frequency converter 7. After receiving the instruction, the frequency converter 7 controls the rotor to stop rotating. In the next step, the unit controller 5 controls the second switching valve 4 on the bypass flow path 2 to open and controls the first switching valve 3 at the suction port 101 to close, ensuring that the rotor is not affected by the airflow impact and does not rotate before it stops levitating. In the next step, it delays for c (10 < c < 60) seconds to wait for the rotor coasting to end, that is, the rotational speed of the rotor drops to 0 rpm. The unit controller 5 sends a stop levitation instruction to the bearing controller 6. After receiving the instruction, the bearing controller 6 controls the rotor to stop levitating. It delays for d (0 < d < 30) seconds to wait for the rotor to stop levitating, and the rotor safely lands on the protection bearing, and the shutdown is completed.

[0058] Among them, the present invention can solve the problem that the magnetic levitation compressor 1 cannot be started normally because the rotor rotates under external force and the rotor cannot levitate and rotate normally. And it can also solve the problem that there is an airflow impact during the process of the rotor stopping levitation, causing rotation, which is likely to cause rotor instability or friction between the rotor and the protection bearing, affecting the service life of the protection bearing and shortening it.

[0059] The technical solution of the present invention can control the rotor to maintain a rotational speed of 0 rpm during the levitation process, control the rotor to levitate normally. And it can also control the rotor to maintain a rotational speed of 0 rpm after levitation and start rotating from 0 rpm, improving the reliability of the magnetic levitation compressor 1. And it can also control the rotor to ensure that the rotational speed of the rotor is 0 rpm when stopping levitating, ensuring that the rotor lands safely without friction and extending the service life of the protection bearing.

[0060] Among them, the aforementioned first switching valve 3 (or guide vane mechanism), second switching valve 4, bearing controller 6 of the magnetic levitation compressor 1, frequency converter 7 of the magnetic levitation compressor 1 and unit controller 5 constitute the unit control device of the magnetic levitation compressor 1. When both the first switching valve 3 and the second switching valve 4 are solenoid valves, the unit controller 5 can control the opening or closing of the first switching valve 3 and the second switching valve 4, and can send a levitation instruction or a stop levitation instruction to the bearing controller 6 of the magnetic levitation compressor 1, and can send a rotation instruction, a rotational speed instruction or a stop rotation instruction to the frequency converter 7 of the compressor.

[0061] It is easy for those skilled in the art to understand that, on the premise of no conflict, the advantageous technical features of the above various methods can be freely combined and superimposed.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention. These improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A magnetic levitation compressor assembly, characterized in that: The invention comprises a magnetic suspension compressor (1) and a bypass flow path (2), wherein the magnetic suspension compressor (1) has an air intake port (101) and an air discharge port (102), wherein the magnetic suspension compressor (1) introduces a refrigerant to be compressed through the air intake port (101) and discharges the compressed refrigerant through the air discharge port (102); The air intake port (101) can be opened or closed; the bypass flow path (2) is connected between the upstream side of the air intake port (101) and the air exhaust port (102), so that when the air intake port (101) is closed, the magnetic levitation compressor assembly can guide the refrigerant flowing to the air intake port (101) to the air exhaust port (102) through the bypass flow path (2); the bypass flow path (2) can be opened or closed.

2. The magnetic suspension compressor assembly according to claim 1, characterized in that: The magnetic levitation compressor assembly further comprises a first switch valve (3), wherein the first switch valve (3) is arranged on a pipeline between an air inlet (21) of the bypass flow path and the air intake port (101) to control the opening or closing of the air intake port (101).

3. The magnetic levitation compressor assembly according to claim 1, characterized in that: A guide vane mechanism with a controllable opening is provided at the air intake port (101), and the guide vane mechanism is used to control the opening or closing of the air intake port (101).

4. The magnetic suspension compressor assembly according to any one of claims 1 to 3, characterized in that: The magnetic levitation compressor assembly further comprises a second switch valve (4), wherein the second switch valve (4) is arranged on the bypass flow path (2) to control the opening or closing of the bypass flow path (2).

5. A control method for a magnetically suspended compressor assembly according to any one of claims 1 to 4, characterized in that: When the magnetic levitation compressor (1) is turned on, steps S11 and S12 are executed in sequence, wherein step S11 is to control the air intake port (101) to be closed and the bypass flow path (2) to be opened; and step S12 is to control the rotor of the magnetic levitation compressor (1) to be suspended. And / or, when the magnetic levitation compressor (1) is shut down, step S21 and step S22 are executed in sequence, step S21 is: controlling the air intake port (101) to be closed and the bypass flow path (2) to be opened; step S22 is: controlling the rotor of the magnetic levitation compressor (1) to stop levitation.

6. The control method according to claim 5, characterized in that: When the magnetic levitation compressor (1) is turned on, steps S13 and S14 are sequentially executed after step S12. Step S13 is to control the rotor of the magnetic levitation compressor (1) to rotate to a target speed. Step S14 is to control the air intake port (101) to open and the bypass flow path (2) to close.

7. The control method according to claim 6, characterized in that: In step S13, a rotation instruction is sent to the frequency converter (7) through the unit controller (5), so that the frequency converter (7) controls the rotor of the magnetic suspension compressor (1) to rotate to a target speed; wherein: In step S12, a suspension instruction is sent to a bearing controller (6) via a unit controller (5), so that the bearing controller (6) controls the rotor of the magnetic suspension compressor (1) to suspend; wherein, after the unit controller (5) sends the suspension instruction to the bearing controller (6) in step S12, it delays for a time a and then sends a rotation instruction to the frequency converter (7) in step S13; And / or, in step S14, the air intake port (101) is controlled to be opened and the bypass flow path (2) is controlled to be closed through the unit controller (5); wherein, after the unit controller (5) sends a rotation instruction to the frequency converter (7) in step S13, the air intake port (101) is controlled to be opened and the bypass flow path (2) is controlled to be closed again in step S14 after a delay time b.

8. The control method according to claim 5, characterized in that: When the magnetic levitation compressor (1) is shut down, step S20 is also executed before step S21. Step S20 is: controlling the rotor of the magnetic levitation compressor (1) to stop rotating.

9. The control method according to claim 8, characterized in that: In step S21, the unit controller (5) controls the air intake port (101) to be closed and the bypass flow path (2) to be opened; in step S22, the unit controller (5) sends a suspension stop instruction to the bearing controller (6), so that the bearing controller (6) controls the rotor of the magnetic suspension compressor (1) to stop suspension; wherein, after the unit controller (5) controls the air intake port (101) to be closed and the bypass flow path (2) to be opened in step S21, a delay time c is applied before sending a suspension stop instruction to the bearing controller (6) in step S22.

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