A blower based on magnetic combined axial force balance and control method thereof

Abstract

The present invention relates to a blower based on magnetic combined axial force balance and a control method thereof, and belongs to the technical field of blower axial force regulation. An axial air suspension bearing and an axial magnetic bearing are arranged in the main engine of the blower, and the axial magnetic bearing is connected to a magnetic bearing controller, and the magnetic bearing controller controls the axial position of the rotor by controlling the current of the axial magnetic bearing; and an axial displacement sensor and a radial displacement sensor are arranged to detect the displacement of the rotor; the main controller is used to control the axial magnetic bearing, the start and stop of the main engine, and issue an early warning based on the axial displacement and radial displacement of the rotor. The magnetic combined axial force balance provided by the present invention utilizes the axial magnetic bearing to provide active control force, and the air bearing to provide passive support, thereby providing stability and reliability of the system, and playing an important protective role for the core components of the blower.

Description

Technical Field

[0001] The invention relates to a blower based on magnetic combined axial force balance and a control method thereof, belonging to the technical field of blower axial force regulation. Background Art

[0002] The core components of the air-suspended high-speed fan include impeller, volute, high-speed motor stator, rotor, radial air suspension bearing, axial air suspension bearing, etc.; the motor stator housing has radial air suspension bearings at both ends to provide radial support for the motor rotor; the axial air suspension bearing generates axial force on the rotor to provide axial positioning and prevent axial movement.

[0003] During the operation of the air suspension high-speed fan, the high-speed rotation of the three-dimensional flow impeller will generate a large axial force on the rotor, resulting in the air suspension bearing, especially the axial air suspension bearing, still being a link with a relatively high failure rate in the entire air suspension system.

[0004] At present, different manufacturers have improved the problem of rotor axial force imbalance by optimizing the impeller design, setting up double thrust plates or optimizing the design of the air suspension system. However, the ability to adjust the rotor axial force is still insufficient, and the expected effect cannot be achieved, which affects the service life of the air suspension blower.

[0005] Currently, there is an urgent need for an air suspension blower that can effectively adjust the axial force of the rotor. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention provides a blower based on magnetic combined axial force balance and a control method thereof. When the axial displacement of the rotor exceeds a set value, the axial magnetic bearing and the axial air suspension bearing work together to change the axial displacement of the rotor, thereby effectively regulating the axial force of the rotor and ensuring the stable operation of the blower.

[0007] At the same time, the present invention also provides a control method for the above-mentioned blower.

[0008] The technical solution of the present invention is:

[0009] In one aspect, the present invention provides a blower based on magnetic combined axial force balance, comprising a host, a magnetic bearing controller and a main controller;

[0010] The main engine includes a housing, a rotor, a stator, a radial air suspension bearing, an axial air suspension bearing and an axial magnetic bearing. The radial air suspension bearing includes a front radial air suspension bearing and a rear radial air suspension bearing. The stator is sleeved on the outside of the rotor.

[0011] The left end of the rotor passes through the front radial air suspension bearing, axial air suspension bearing and main impeller from inside to outside.

[0012] The right end of the rotor is sequentially mounted from inside to outside through the rear radial air suspension bearing, the axial magnetic bearing and the heat dissipation impeller; and the maximum movable displacement of the axial magnetic bearing in the negative / positive direction of the Z axis is greater than the maximum movable displacement of the axial air suspension bearing in the negative / positive direction of the Z axis;

[0013] The axial magnetic bearing is connected to a magnetic bearing controller, and the magnetic bearing controller controls the axial position of the rotor by controlling the current of the axial magnetic bearing;

[0014] An axial displacement sensor is arranged on the right side of the rotor along the Z-axis direction to detect the axial displacement of the rotor, and radial displacement sensors are arranged on the inner side of the axial magnetic bearing along the X-axis and Y-axis directions to detect the radial displacement of the rotor;

[0015] The main controller is used to control the axial magnetic bearing, the start and stop of the main engine, and issue an early warning based on the axial displacement and radial displacement of the rotor.

[0016] Preferably, according to the present invention, a front radial air suspension bearing seat is provided at the front end of the casing, and a front radial air suspension bearing is provided between the front radial air suspension bearing seat and the rotor; a rear radial air suspension bearing seat is provided at the rear end of the casing, and a rear radial air suspension bearing is provided between the rear radial air suspension bearing seat and the rotor.

[0017] Preferably, according to the present invention, a front cover plate is arranged on the outer side of the front radial air suspension bearing seat, an axial air suspension bearing is arranged between the front radial air suspension bearing seat and the front cover plate, the axial air suspension bearing comprises a first thrust plate, an axial bearing seat, a corrugated foil and a top foil, and a top foil, a corrugated foil and an axial bearing seat are arranged in sequence from the inside to the outside on the front and rear sides of the first thrust plate.

[0018] Preferably, according to the present invention, an axial magnetic bearing seat is arranged on the outer side of the rear radial air suspension bearing seat, and the axial magnetic bearing is sleeved inside the axial magnetic bearing seat; the axial magnetic bearing includes a front axial magnetic bearing, a second thrust plate and a rear axial magnetic bearing, the second thrust plate is sleeved on the rotor, and the front axial magnetic bearing and the rear axial magnetic bearing are respectively arranged in front and behind the second thrust plate.

[0019] Preferably according to the present invention, a rear cover plate is provided between the axial magnetic bearing and the heat dissipation impeller, an end cover is provided on the outer side of the rear cover plate, an axial displacement sensor is provided on the end cover, and a temperature sensor is provided on one side of the axial displacement sensor.

[0020] Preferably, according to the present invention, the rotor comprises a permanent magnetic core, a shaft head and a pull rod, and shaft heads are arranged at both ends of the permanent magnetic core;

[0021] One end of the left tie rod passes through the shaft head and is threadedly connected to the permanent magnetic core, and the other end of the left tie rod passes through the main impeller, and the outer side of the main impeller is fixed to the left tie rod through a nut; and an axial adjustment impeller is arranged between the left shaft head and the permanent magnetic core, which is used to drain the air between the front radial control bearing and the rotor and balance the axial force on the rotor;

[0022] One end of the right pull rod passes through the shaft head and is threadedly connected to the permanent magnet core body, the other end of the right pull rod passes through the heat dissipation impeller, and the outer side of the heat dissipation impeller is fixed to the right pull rod through a nut.

[0023] On the other hand, the present invention also provides a control method for the above-mentioned blower based on magnetic combined axial force balance, comprising:

[0024] Calibrate the radial displacement sensor and the axial displacement sensor respectively;

[0025] Collect the displacement X of the rotor in the X-axis direction, the displacement Y in the Y-axis direction, and the displacement Z in the Z-axis direction to obtain the displacement offset △X of the rotor in the X-axis direction, the displacement offset △Y of the rotor in the Y-axis direction, and the displacement offset △Z of the rotor in the Z-axis direction;

[0026] When the displacement of the rotor in the X-axis direction △X exceeds the set value, the main controller will issue an early warning and shut down the machine;

[0027] And / or, when the displacement offset △Y of the rotor in the Y-axis direction exceeds the set value, the main controller issues an early warning and shuts down;

[0028] When the displacement offset △Z of the rotor in the Z-axis direction exceeds the set value, the main controller starts the axial magnetic bearing to adjust the displacement offset of the rotor in the Z-axis direction.

[0029] Preferably, according to the present invention, the calibration process of the radial displacement sensor and the axial displacement sensor is:

[0030] When the rotor in the host is not floating, only the force is applied to the negative / positive direction of the rotor on the X-axis, so that the radial air suspension bearing reaches the maximum movable displacement X1 / X2 in the negative / positive direction of the X-axis, and the output value of the corresponding displacement sensor module is calibrated to be A1 / A2, then the radial displacement output range in the X-axis direction is [A1, A2]; when the rotor is in the middle of the maximum movable displacement in the X-axis direction, the output value of the radial displacement sensor in the X-axis direction is calibrated to be (A1+A2) / 2;

[0031] In the case where the rotor in the main machine is not levitated, a force is applied only in the negative / positive Y-axis direction of the rotor, so that the radial air suspension bearing reaches the maximum movable displacement Y1 / Y2 in the negative / positive Y-axis direction, and the output values of the corresponding displacement sensor module are calibrated as B1 / B2. Then, the radial displacement output range in the Y-axis direction is [B1, B2]; when the rotor is at the middle of the maximum movable displacement in the Y-axis direction, the output value of the radial displacement sensor in the Y-axis direction is calibrated as (B1 + B2) / 2;

[0032] In the case where the rotor in the main machine is not levitated, a force is applied only in the negative / positive Z-axis direction of the rotor, so that the axial air suspension bearing reaches the maximum movable displacement Z1 / Z2 in the negative / positive Z-axis direction, and the output values of the corresponding displacement sensor module are calibrated as C1 / C2. Then, the displacement signal output range in the Z-axis direction is [C1, C2]; when the rotor is at the middle of the maximum movable displacement in the Z-axis direction, the output value of the axial displacement sensor in the Z-axis direction is calibrated as (C1 + C2) / 2.

[0033] According to a preferred embodiment of the present invention, the displacement offset amount △X of the rotor in the X-axis direction = 丨X - (X1 + X2) / 2丨;

[0034] The displacement offset amount △Y of the rotor in the Y-axis direction = 丨Y - (Y1 + Y2) / 2丨;

[0035] The displacement offset amount △Z of the rotor in the Z-axis direction = 丨Z - (Z1 + Z2) / 2丨;

[0036] The set value A of the displacement offset amount △X of the rotor in the X-axis direction is (X2 - X1 + 2aM) / 2; M is the maximum recoverable deformation amount of the radial air suspension bearing in the x-axis direction; a is the safety factor of the radial air suspension bearing in the X-axis direction;

[0037] The set value B of the displacement offset amount △Y of the rotor in the Y-axis direction is (Y2 - Y1 + 2bN) / 2; N is the maximum recoverable deformation amount of the radial air suspension bearing in the y-axis direction; b is the safety factor of the radial air suspension bearing in the Y-axis direction;

[0038] The set value C of the displacement offset amount △Z of the rotor in the Z-axis direction is (Z2 - Z1 + 2cQ) / 2; Q is the maximum recoverable deformation amount of the axial air suspension bearing in the z-axis direction, and c is the safety factor of the axial air suspension bearing in the Z-axis direction. a and b are determined according to the deformable limit of the foil in the radial air suspension bearing, and c is determined according to the deformable limit of the wave foil in the axial air suspension bearing.

[0039] According to a preferred embodiment of the present invention, when the displacement offset amount △Z of the rotor in the Z-axis direction exceeds the set value, the main controller activates the axial magnetic bearing to regulate the displacement offset of the rotor in the Z-axis direction; specifically:

[0040] (1) When △Z exceeds the set value C, the magnetic bearing controller activates the power supply of the axial magnetic bearing;

[0041] (2) The magnetic bearing controller calculates the required electromagnetic force to pull the rotor back to the middle of the maximum movable displacement in the Z-axis direction;

[0042] (3) Adjust the current of the axial magnetic bearing according to the calculated required electromagnetic force so that △Z < C;

[0043] (4) When △Z < C, start timing the stabilization time t;

[0044] If the stabilization time t ≥ the set time T, reduce the electromagnetic force of the axial magnetic bearing or directly turn off the axial magnetic bearing, and the rotor is supported by the axial air suspension bearing and the radial air suspension bearing, and the adjustment ends;

[0045] If the stabilization time t < the set time T, continue to use the axial magnetic bearing for adjustment, repeat the above steps (1)-(3), and record the number of times of repeating steps (1)-(3) within the specified time;

[0046] (5) If the number of times of repeating steps (1)-(3) within the specified time is greater than the set value N, the main controller shuts down the host and issues a warning signal, then gradually reduces the electromagnetic force of the axial magnetic bearing, and finally turns off the axial magnetic bearing. By using the method of multiple axial magnetic bearing adjustments to reasonably judge the problems of the current working conditions, when it is difficult to control the axial displacement through the axial magnetic bearing for sudden situations, the equipment damage is reduced by shutting down, which greatly delays the operation life of the equipment.

[0047] The beneficial effects of the present invention are as follows:

[0048] 1. The present invention provides a blower based on magnetic-gas combined axial force balance, installs a displacement sensor in the host, can monitor the position of the rotor in real time, and at the same time sets an axial magnetic bearing and axial air suspension. The axial magnetic bearing can quickly respond and adjust the electromagnetic force to ensure the stable suspension of the rotor.

[0049] 2. The magnetic-gas combined axial force balance provided by the present invention uses the axial magnetic bearing to provide active control force, and the radial air bearing and axial air suspension bearing provide passive support, providing the stability and reliability of the system. By setting the threshold of the displacement offset, the warning and automatic shutdown functions are realized, effectively preventing the rotor from contacting the bearing and protecting the equipment from damage.

[0050] 3. When the axial displacement of the rotor exceeds the set value, the system automatically switches to the magnetic bearing control mode to provide additional axial control force; when the rotor stabilizes, the system can gradually reduce the electromagnetic force of the magnetic bearing and switch back to the air bearing support mode to achieve energy saving and reduce magnetic loss.

[0051] 4. The axial magnetic bearing control method designed by the present invention is designed to reasonably judge the current working condition problems through multiple axial magnetic bearing adjustment methods. When it is difficult to control the axial displacement through the axial magnetic bearing in case of emergencies, the damage to the equipment is reduced by shutting down, which greatly delays the operating life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 A schematic structural diagram of a main engine in a blower based on magnetic combined axial force balance provided by the present invention.

[0053] Figure 2 for Figure 1 A magnified schematic diagram of area A in the middle.

[0054] Figure 3 A schematic diagram of the partial structure of a main engine in a blower based on magnetic combined axial force balance provided by the present invention.

[0055] 1. stator, 2. rotor, 3. casing, 4. front radial air suspension bearing, 5. rear radial air suspension bearing, 6. front radial air suspension bearing seat, 7. rear radial air suspension bearing seat, 8. top foil, 9. axial magnetic bearing seat, 10. front axial magnetic bearing, 11. rear axial magnetic bearing, 12. temperature sensor, 13. end cover, 14. axial displacement sensor, 15. air cylinder, 16. cooling impeller, 17. radial displacement sensor, 18. rear cover, 19. front cover, 20. first thrust plate, 21. wave foil, 22. axial bearing seat, 23. second thrust plate, 24. drainage wind cover, 25. axial adjustment impeller, 26. main impeller, 27. permanent magnetic core, 28. shaft head, 29. pull rod. DETAILED DESCRIPTION

[0056] Several embodiments of the present application will be disclosed below with diagrams to clearly and completely describe the technical solution of the present invention. The drawings in the specification are used to provide a further understanding of the present invention. The schematic embodiments and descriptions of the present invention are used to explain the present invention and do not constitute improper limitations on the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0057] It should be noted that unless a direction is defined separately, the directions such as up, down, left, and right mentioned in this document are based on the embodiments of this application. Figure 1The directions of up, down, left, right, etc. shown in the figure shall prevail. If the specific posture changes, the directional indication will also change accordingly. The words "first", "second" and similar words used in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. In addition, in various embodiments of the present disclosure, the same or similar reference numerals represent the same or similar components.

[0058] In the present invention, unless otherwise clearly defined and specified, the terms "connection", "fixation" and the like should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral body, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0060] Example 1

[0061] This embodiment provides a blower based on magnetic combined axial force balance, such as Figure 1 , Figure 2 and Figure 3 As shown, it includes a host, a magnetic bearing controller and a main controller;

[0062] The main machine includes a housing 3, a rotor 2, a stator 1, a radial air suspension bearing, an axial air suspension bearing and an axial magnetic bearing. The radial air suspension bearing includes a front radial air suspension bearing 4 and a rear radial air suspension bearing 5. The stator 1 is sleeved on the outside of the rotor 2.

[0063] The left end of the rotor 2 is sequentially inserted through the front radial air suspension bearing 4, the axial air suspension bearing and the main impeller 26 from the inside to the outside.

[0064] The right end of the rotor 2 is sequentially fitted through the rear radial air suspension bearing 5, the axial magnetic bearing and the heat dissipation impeller 16 from the inside to the outside; and the maximum movable displacement of the axial magnetic bearing in the negative / positive direction of the Z axis is greater than the maximum movable displacement of the axial air suspension bearing in the negative / positive direction of the Z axis; the radial direction of the rotor 2 is set to the X-axis direction and the Y-axis direction, and the axial direction of the rotor 2 is set to the Z-axis direction. The maximum movable displacement is the maximum displacement that the rotor 2 can move in the negative / positive direction of the X-axis, Y-axis or Z-axis.

[0065] The axial magnetic bearing is connected to a magnetic bearing controller, and the magnetic bearing controller controls the axial position of the rotor 2 by controlling the current of the axial magnetic bearing;

[0066] An axial displacement sensor 14 is arranged on the right side of the rotor 2 along the Z-axis direction, which is used to detect the axial displacement of the rotor 2. Radial displacement sensors 17 are respectively arranged on the inner side of the axial magnetic bearing along the X-axis and Y-axis directions, which are used to detect the radial displacement of the rotor 2; specifically, a radial displacement sensor 17 is respectively arranged in the positive and negative directions of the X-axis of the rotor 2, and a radial displacement sensor 17 is respectively arranged in the positive and negative directions of the Y-axis of the rotor 2.

[0067] The main controller is used to control the axial magnetic bearing, the start and stop of the main engine, and issue an early warning based on the axial displacement and radial displacement of the rotor 2. The magnetic bearing controller and the main controller are not shown in the drawings.

[0068] Example 2

[0069] This embodiment provides a blower based on magnetic combined axial force balance, which is different from Embodiment 1 in that:

[0070] A front radial air suspension bearing seat 6 is arranged at the front end of the casing 3, and a front radial air suspension bearing 4 is arranged between the front radial air suspension bearing seat 6 and the rotor 2; a rear radial air suspension bearing seat 7 is arranged at the rear end of the casing 3, and a rear radial air suspension bearing 5 is arranged between the rear radial air suspension bearing seat 7 and the rotor 2.

[0071] Example 3

[0072] This embodiment provides a blower based on magnetic combined axial force balance, which is different from Embodiment 2 in that:

[0073] A front cover plate 19 is arranged on the outer side of the front radial air suspension bearing seat 6, and an axial air suspension bearing is arranged between the front radial air suspension bearing seat 6 and the front cover plate 19. The axial air suspension bearing includes a first thrust plate 20, an axial bearing seat 22, a bump foil 21 and a top foil 8. The top foil 8, the bump foil 21 and the axial bearing seat 22 are arranged in sequence from the inside to the outside on the front and rear sides of the first thrust plate 20.

[0074] Example 4

[0075] This embodiment provides a blower based on magnetic combined axial force balance, which is different from Embodiment 2 in that:

[0076] An axial magnetic bearing seat 9 is arranged on the outer side of the rear radial air suspension bearing seat 7, and the axial magnetic bearing is mounted inside the axial magnetic bearing seat 9; the axial magnetic bearing includes a front axial magnetic bearing 10, a second thrust plate 23 and a rear axial magnetic bearing 11, the second thrust plate 23 is mounted on the rotor 2, and the front axial magnetic bearing 10 and the rear axial magnetic bearing 11 are respectively arranged in front and behind the second thrust plate 23.

[0077] Example 5

[0078] This embodiment provides a blower based on magnetic combined axial force balance, which is different from Embodiment 4 in that:

[0079] A rear cover plate 18 is also provided between the axial magnetic bearing and the heat dissipation impeller 16, and a ventilation hole is provided on the rear cover plate 18; the air in the housing 3 can flow through the ventilation hole to the air duct 15, then pass through the heat dissipation impeller 16, and finally be discharged to the outside. An end cover 13 is also provided on the outside of the rear cover plate 18. Specifically, a drainage hood 24 is provided on the outside of the heat dissipation impeller 16, and a wind duct 15 is provided on the outside of the drainage hood 24, and an end cover 13 is provided on the outside of the wind duct 15; an axial displacement sensor 14 is provided on the end cover 13, and a temperature sensor 12 is provided on one side of the axial displacement sensor 14.

[0080] Example 6

[0081] This embodiment provides a blower based on magnetic combined axial force balance, which is different from Embodiment 1 in that:

[0082] The rotor 2 includes a permanent magnetic core 27, a shaft head 28 and a pull rod 29. The shaft heads 28 are provided at both ends of the permanent magnetic core 27.

[0083] One end of the left tie rod 29 passes through the shaft head 28 and is threadedly connected to the permanent magnetic core 27, and the other end of the left tie rod 29 passes through the main impeller 26, and the outer side of the main impeller 26 is fixed to the left tie rod 29 through a nut; and an axial adjustment impeller 25 is arranged between the left shaft head 28 and the permanent magnetic core 27, which is used to drain the air between the front radial control bearing and the rotor 2 and balance the axial force on the rotor 2;

[0084] One end of the right tie rod 29 passes through the shaft head 28 and is threadedly connected to the permanent magnet core 27 , and the other end of the right tie rod 29 passes through the heat dissipation impeller 16 , and the outer side of the heat dissipation impeller 16 is fixed to the right tie rod 29 by a nut.

[0085] The axial adjustment impeller 25 is installed in the same direction as the main impeller 26, and the heat dissipation impeller 16 is installed in the opposite direction to the axial adjustment impeller 25. The installation direction refers to the positional relationship and direction between the large end and the small end of the impeller.

[0086] Example 7

[0087] This embodiment provides a control method for a blower based on magnetic combined axial force balance provided in any one of Embodiments 1 to 6, including:

[0088] Collect the displacement X in the X-axis direction, the displacement Y in the Y-axis direction, and the displacement Z in the Z-axis direction of the rotor 2 to obtain the displacement offset △X of the rotor 2 in the X-axis direction, the displacement offset △Y of the rotor 2 in the Y-axis direction, and the displacement offset △Z of the rotor 2 in the Z-axis direction;

[0089] When the displacement offset △X of rotor 2 in the X-axis direction exceeds the set value, the main controller issues an early warning and shuts down the machine;

[0090] And / or, when the displacement offset △Y of the rotor 2 in the Y-axis direction exceeds the set value, the main controller issues an early warning and shuts down;

[0091] When the displacement offset △Z of the rotor 2 in the Z-axis direction exceeds the set value, the main controller starts the axial magnetic bearing to adjust the displacement offset of the rotor 2 in the Z-axis direction.

[0092] Example 8

[0093] This embodiment provides a control method for a blower based on magnetic combined axial force balance, which is different from Embodiment 7 in that:

[0094] The calibration process of the radial displacement sensor 17 and the axial displacement sensor 14 is as follows:

[0095] When the rotor 2 in the host is not floating, only the force is applied to the rotor 2 in the negative / positive direction of the X-axis, so that the radial air suspension bearing reaches the maximum movable displacement X1 / X2 in the negative / positive direction of the X-axis, and the output value of the corresponding displacement sensor module is calibrated to be A1 / A2, then the radial displacement output interval in the X-axis direction is [A1, A2]; when the rotor 2 is in the middle of the maximum movable displacement in the X-axis direction, the output value of the radial displacement sensor 17 in the X-axis direction is calibrated to be (A1+A2) / 2;

[0096] It should be noted that in order to make the radial air suspension bearing or the axial air suspension bearing have a greater bearing capacity, the design of the bump foil 21 can withstand a certain deformation, and the deformation can be restored within a certain range. When the maximum recoverable deformation is exceeded, the deformation of the bump foil 21 cannot be completely restored. The maximum recoverable deformation on the X-axis, Y-axis or Z-axis will vary with the design parameters of the radial air suspension bearing or the axial air suspension bearing.

[0097] In the case where the rotor 2 in the main machine has not been levitated, a force is applied only in the negative / positive Y-axis direction of the rotor 2, so that the radial air suspension bearing reaches the maximum movable displacement Y1 / Y2 in the negative / positive Y-axis direction, and the output values of the corresponding displacement sensor module are calibrated as B1 / B2. Then, the radial displacement output range in the Y-axis direction is [B1, B2]; when the rotor 2 is at the middle of the maximum movable displacement in the Y-axis direction, the output value of the radial displacement sensor 17 in the Y-axis direction is calibrated as (B1 + B2) / 2.

[0098] In the case where the rotor 2 in the main machine has not been levitated, a force is applied only in the negative / positive Z-axis direction of the rotor 2, so that the axial air suspension bearing reaches the maximum movable displacement Z1 / Z2 in the negative / positive Z-axis direction, and the output values of the corresponding displacement sensor module are calibrated as C1 / C2. Then, the displacement signal output range in the Z-axis direction is [C1, C2]; when the rotor 2 is at the middle of the maximum movable displacement in the Z-axis direction, the output value of the axial displacement sensor 14 in the Z-axis direction is calibrated as (C1 + C2) / 2.

[0099] Embodiment 9

[0100] This embodiment provides a control method for a blower based on magnetic-gas combined axial force balance. The difference from Embodiment 8 is as follows:

[0101] The displacement offset △X of the rotor 2 in the X-axis direction = 丨X - (X1 + X2) / 2丨;

[0102] The displacement offset △Y of the rotor 2 in the Y-axis direction = 丨Y - (Y1 + Y2) / 2丨;

[0103] The displacement offset △Z of the rotor 2 in the Z-axis direction = 丨Z - (Z1 + Z2) / 2丨;

[0104] The set value A of the displacement offset △X of the rotor 2 in the X-axis direction is (X2 - X1 + 2aM) / 2; M is the maximum recoverable deformation amount of the radial air suspension bearing in the x-axis direction; a is the safety factor of the radial air suspension bearing in the X-axis direction;

[0105] The set value B of the displacement offset △Y of the rotor 2 in the Y-axis direction is (Y2 - Y1 + 2bN) / 2; N is the maximum recoverable deformation amount of the radial air suspension bearing in the y-axis direction; b is the safety factor of the radial air suspension bearing in the Y-axis direction;

[0106] The set value C of the displacement offset △Z of the rotor 2 in the Z-axis direction is (Z2 - Z1 + 2cQ) / 2; Q is the maximum recoverable deformation amount of the axial air suspension bearing in the z-axis direction, and c is the safety factor of the axial air suspension bearing in the Z-axis direction.

[0107] The design parameters of different axial air suspension bearings, the front radial air suspension bearing 4, and the rear radial air suspension bearing 5 are different, and the set values will also be different. a and b are determined according to the deformable limit of the foil in the radial air suspension bearing, and c is determined according to the deformable limit of the wave foil 21 in the axial air suspension bearing.

[0108] Example 10

[0109] This embodiment provides a control method for a blower based on the magnetic gas combined axial force balance. The difference from Example 9 is as follows:

[0110] When the displacement offset △Z of the rotor 2 in the Z-axis direction exceeds the set value, the main controller activates the axial magnetic bearing to regulate the displacement offset of the rotor 2 in the Z-axis direction. Specifically:

[0111] (1) When △Z exceeds the set value C, the magnetic bearing controller activates the power supply of the axial magnetic bearing;

[0112] (2) The magnetic bearing controller calculates the required electromagnetic force to pull the rotor 2 back to the middle of the maximum movable displacement in the Z-axis direction;

[0113] (3) Adjust the current of the axial magnetic bearing according to the calculated required electromagnetic force so that △Z < C;

[0114] (4) When △Z < C, start timing the stabilization time t;

[0115] If the stabilization time t ≥ the set time T, reduce the electromagnetic force of the axial magnetic bearing or directly turn off the axial magnetic bearing. The rotor 2 is supported by the axial air suspension bearing and the radial air suspension bearing, and the adjustment ends;

[0116] If the stabilization time t < the set time T, continue to use the axial magnetic bearing for adjustment, repeat the above steps (1)-(3), and record the number of times of repeating steps (1)-(3) within the specified time;

[0117] If the number of times of repeating steps (1)-(3) within the specified time is greater than the set value N, the main controller shuts down the host and issues a warning signal, then gradually reduces the electromagnetic force of the axial magnetic bearing, and finally turns off the axial magnetic bearing.

[0118] The axial magnetic bearing control method designed by the present invention designs a method of adjusting the axial magnetic bearing multiple times to reasonably judge the problems of the current working conditions. When it is difficult to control the axial displacement through the axial magnetic bearing for sudden situations, the equipment damage is reduced by shutting down, which greatly delays the operation life of the equipment.

[0119] The above description shows and describes the preferred implementation of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other implementations, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the object concept of this article through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the present application, and should be within the scope of protection of the claims attached to the present application.

Claims

1. A control method for a blower based on magnetic combined axial force balance, characterized in that: The blower includes a host, a magnetic bearing controller and a main controller; the host includes a casing, a rotor, a stator, a radial air suspension bearing, an axial air suspension bearing and an axial magnetic bearing, the radial air suspension bearing includes a front radial air suspension bearing and a rear radial air suspension bearing, and the stator is sleeved on the outside of the rotor; the left end of the rotor is sleeved through the front radial air suspension bearing, the axial air suspension bearing and the main impeller from the inside to the outside, and the right end of the rotor is sleeved through the rear radial air suspension bearing, the axial magnetic bearing and the heat dissipation impeller from the inside to the outside; and the maximum movable displacement of the axial magnetic bearing in the negative / positive direction of the Z axis is greater than the maximum movable displacement of the axial air suspension bearing in the negative / positive direction of the Z axis; the axial magnetic bearing is connected to the magnetic bearing controller, and the magnetic bearing controller controls the axial position of the rotor by controlling the current of the axial magnetic bearing; an axial displacement sensor is arranged on the right side of the rotor along the Z axis direction for detecting the axial displacement of the rotor, and radial displacement sensors are arranged on the inner side of the axial magnetic bearing along the X axis and Y axis directions for detecting the radial displacement of the rotor; The main controller is used to control the axial magnetic bearing, the start and stop of the main engine, and issue an early warning based on the axial displacement and radial displacement of the rotor; Blower control methods include: Calibrate the radial displacement sensor and the axial displacement sensor respectively, including: when the rotor in the main engine is not floating, only apply force in the negative / positive direction of the X-axis of the rotor, so that the radial air suspension bearing reaches the maximum movable displacement X1 / X2 in the negative / positive direction of the X-axis, calibrate the output value of the corresponding displacement sensor module to A1 / A2, and then the radial displacement output range in the X-axis direction is [A1, A2]; when the rotor is in the middle of the maximum movable displacement in the X-axis direction, calibrate the output value of the radial displacement sensor in the X-axis direction to (A1+A2) / 2; When the rotor in the host is not floating, only the force is applied to the negative / positive direction of the Y-axis of the rotor, so that the radial air suspension bearing reaches the maximum movable displacement Y1 / Y2 in the negative / positive direction of the Y-axis, and the output value of the corresponding displacement sensor module is calibrated to B1 / B2, then the radial displacement output range in the Y-axis direction is [B1, B2]; when the rotor is in the middle of the maximum movable displacement in the Y-axis direction, the output value of the radial displacement sensor in the Y-axis direction is calibrated to (B1+B2) / 2; When the rotor in the host is not floating, only the force is applied to the negative / positive direction of the Z-axis of the rotor, so that the axial air suspension bearing reaches the maximum movable displacement Z1 / Z2 in the negative / positive direction of the Z-axis, and the output value of the corresponding displacement sensor module is calibrated to C1 / C2, then the displacement signal output interval in the Z-axis direction is [C1, C2]; when the rotor is in the middle of the maximum movable displacement in the Z-axis direction, the output value of the axial displacement sensor in the Z-axis direction is calibrated to (C1+C2) / 2; Collect the displacement X in the X-axis direction, displacement Y in the Y-axis direction, and displacement Z in the Z-axis direction of the rotor to obtain the displacement offset ΔX of the rotor in the X-axis direction, the displacement offset ΔY of the rotor in the Y-axis direction, and the displacement offset ΔZ of the rotor in the Z-axis direction; the displacement offset ΔX of the rotor in the X-axis direction = |X - (X1 + X2) / 2|; the displacement offset ΔY of the rotor in the Y-axis direction = |Y - (Y1 + Y2) / 2|; the displacement offset ΔZ of the rotor in the Z-axis direction = |Z - (Z1 + Z2) / 2|; When the displacement offset ΔX of the rotor in the X-axis direction exceeds the set value, the main controller issues a warning and shuts down; the set value A of the displacement offset ΔX of the rotor in the X-axis direction is (X2 - X1 + 2aM) / 2; M is the maximum recoverable deformation of the radial air suspension bearing in the x-axis direction; a is the safety factor of the radial air suspension bearing in the X-axis direction; And / or, when the displacement offset ΔY of the rotor in the Y-axis direction exceeds the set value, the main controller issues a warning and shuts down; the set value B of the displacement offset ΔY of the rotor in the Y-axis direction is (Y2 - Y1 + 2bN) / 2; N is the maximum recoverable deformation of the radial air suspension bearing in the y-axis direction; b is the safety factor of the radial air suspension bearing in the Y-axis direction; When the displacement offset ΔZ of the rotor in the Z-axis direction exceeds the set value, the main controller activates the axial magnetic bearing to regulate the displacement of the rotor in the Z-axis direction; specifically: (1) When ΔZ exceeds the set value C, the magnetic bearing controller activates the power supply of the axial magnetic bearing; the set value C of the displacement offset ΔZ of the rotor in the Z-axis direction is (Z2 - Z1 + 2cQ) / 2; Q is the maximum recoverable deformation of the axial air suspension bearing in the z-axis direction, and c is the safety factor of the axial air suspension bearing in the Z-axis direction; (2) The magnetic bearing controller calculates the required electromagnetic force to pull the rotor back to the middle of the maximum movable displacement in the Z-axis direction; (3) Adjust the current of the axial magnetic bearing according to the calculated required electromagnetic force so that ΔZ < C; (4) When ΔZ < C, start timing the stabilization time t; If the stabilization time t ≥ the set time T, reduce the electromagnetic force of the axial magnetic bearing or directly turn off the axial magnetic bearing, and the rotor is supported by the axial air suspension bearing and the radial air suspension bearing, and the adjustment ends; If the stabilization time t < the set time T, continue to use the axial magnetic bearing for adjustment, repeat the above steps (1)-(3), and record the number of times of repeating steps (1)-(3) within the specified time; (5) If the number of times of repeating steps (1)-(3) within the specified time is greater than the set value N, the main controller shuts down the host and issues a warning signal, then gradually reduces the electromagnetic force of the axial magnetic bearing, and finally turns off the axial magnetic bearing.

2. The control method according to claim 1, characterized in that: A front radial air suspension bearing seat is provided at the front end of the housing, and a front radial air suspension bearing is provided between the front radial air suspension bearing seat and the rotor; a rear radial air suspension bearing seat is provided at the rear end of the housing, and a rear radial air suspension bearing is provided between the rear radial air suspension bearing seat and the rotor.

3. The control method according to claim 2, characterized in that: A front cover plate is arranged on the outer side of the front radial air suspension bearing seat, an axial air suspension bearing is arranged between the front radial air suspension bearing seat and the front cover plate, the axial air suspension bearing comprises a first thrust plate, an axial bearing seat, a corrugated foil and a top foil, and a top foil, a corrugated foil and an axial bearing seat are arranged in sequence from the inside to the outside on the front and rear sides of the first thrust plate.

4. The control method according to claim 2, characterized in that: An axial magnetic bearing seat is arranged on the outer side of the rear radial air suspension bearing seat, and the axial magnetic bearing is sleeved inside the axial magnetic bearing seat; the axial magnetic bearing comprises a front axial magnetic bearing, a second thrust plate and a rear axial magnetic bearing, the second thrust plate is sleeved on the rotor, and the front axial magnetic bearing and the rear axial magnetic bearing are respectively arranged in front and behind the second thrust plate.

5. The control method according to claim 4, characterized in that: A rear cover plate is also arranged between the axial magnetic bearing and the heat dissipation impeller, an end cover is also arranged on the outer side of the rear cover plate, an axial displacement sensor is arranged on the end cover, and a temperature sensor is arranged on one side of the axial displacement sensor.

6. The control method according to claim 1, characterized in that: The rotor comprises a permanent magnetic core, a shaft head and a pull rod, and shaft heads are arranged at both ends of the permanent magnetic core; One end of the left tie rod passes through the shaft head and is threadedly connected to the permanent magnetic core, and the other end of the left tie rod passes through the main impeller, and the outer side of the main impeller is fixed to the left tie rod through a nut; and an axial adjustment impeller is arranged between the left shaft head and the permanent magnetic core, which is used to drain the air between the front radial control bearing and the rotor and balance the axial force on the rotor; One end of the right pull rod passes through the shaft head and is threadedly connected to the permanent magnet core body, the other end of the right pull rod passes through the heat dissipation impeller, and the outer side of the heat dissipation impeller is fixed to the right pull rod through a nut.

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