CN116771795B - Magnetic-air hybrid bearing with interconversion of rigid support and elastic support - Google Patents
Magnetic-air hybrid bearing with interconversion of rigid support and elastic support Download PDFInfo
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- CN116771795B CN116771795B CN202310741942.4A CN202310741942A CN116771795B CN 116771795 B CN116771795 B CN 116771795B CN 202310741942 A CN202310741942 A CN 202310741942A CN 116771795 B CN116771795 B CN 116771795B
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- 238000006073 displacement reaction Methods 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims description 29
- 238000006243 chemical reaction Methods 0.000 claims description 25
- 230000008569 process Effects 0.000 claims description 16
- 230000000694 effects Effects 0.000 claims description 6
- 230000003139 buffering effect Effects 0.000 claims description 3
- 230000006835 compression Effects 0.000 claims description 3
- 238000007906 compression Methods 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 3
- 230000001050 lubricating effect Effects 0.000 claims description 3
- 230000001681 protective effect Effects 0.000 claims description 3
- 230000008878 coupling Effects 0.000 claims description 2
- 238000010168 coupling process Methods 0.000 claims description 2
- 238000005859 coupling reaction Methods 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 abstract description 4
- 239000011888 foil Substances 0.000 description 7
- 238000005299 abrasion Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000009826 distribution Methods 0.000 description 4
- 230000000295 complement effect Effects 0.000 description 2
- 230000005489 elastic deformation Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 230000004323 axial length Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C32/00—Bearings not otherwise provided for
- F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
- F16C32/0406—Magnetic bearings
- F16C32/044—Active magnetic bearings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C32/00—Bearings not otherwise provided for
- F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
- F16C32/0402—Bearings not otherwise provided for using magnetic or electric supporting means combined with other supporting means, e.g. hybrid bearings with both magnetic and fluid supporting means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C32/00—Bearings not otherwise provided for
- F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
- F16C32/0406—Magnetic bearings
- F16C32/044—Active magnetic bearings
- F16C32/0444—Details of devices to control the actuation of the electromagnets
- F16C32/0446—Determination of the actual position of the moving member, e.g. details of sensors
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C32/00—Bearings not otherwise provided for
- F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
- F16C32/0406—Magnetic bearings
- F16C32/044—Active magnetic bearings
- F16C32/0444—Details of devices to control the actuation of the electromagnets
- F16C32/0451—Details of controllers, i.e. the units determining the power to be supplied, e.g. comparing elements, feedback arrangements with P.I.D. control
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Magnetic Bearings And Hydrostatic Bearings (AREA)
Abstract
The invention provides a magnetic-air hybrid bearing with a mutually-converted rigid support and an elastic support, and belongs to the technical field of bearings. The hybrid bearing is provided with a protection bearing, a magnetic bearing and a gas bearing along the axial direction of a rotor, wherein the magnetic bearing axially comprises magnetic poles, magnetic pole coils and a displacement sensor, the magnetic poles are wound by the magnetic pole coils, the axial front side of the magnetic pole coils of the magnetic bearing is provided with the protection bearing, the axial rear side of the magnetic pole coils of the magnetic bearing is provided with the displacement sensor, and the axial rear side of the displacement sensor is provided with the gas bearing. A magnetic bearing radius gap is formed between the magnetic bearing magnetic pole and the rotor, a magnetic pole coil is connected with a power amplifier, and a magnetic-air hybrid bearing controller is connected between the power amplifier and the displacement sensor; the outer ring of the air bearing fixing frame is a fixing frame ring, a fixing frame wedge groove is formed in the outer ring of the air bearing fixing frame, a rotor is arranged in the center of the ring where the fixing frame wedge groove is located, and an air bearing bush and elastic rubber are arranged between the rotor and the fixing frame wedge groove. The invention can reduce the heating and power consumption of the magnetic bearing, prolong the service life of the bearing and has excellent comprehensive performance.
Description
Technical Field
The invention relates to the technical field of bearings, in particular to a magnetic-air hybrid bearing with mutually converted rigid support and elastic support.
Background
The magnetic bearing is a high-performance bearing which realizes suspension by utilizing electromagnetic force, and compared with the traditional ball bearing, sliding bearing and oil film bearing, the magnetic bearing has no mechanical contact, the rotor can reach higher running speed, and the magnetic bearing has the advantages of no friction and abrasion, no need of lubrication, long service life and the like, and is particularly suitable for special environments such as high speed, vacuum, ultra-clean and the like. However, the magnetic bearing has the disadvantage that the bearing needs to be protected, and the protection bearing can play a role in protection when the magnetic bearing fails. Because the magnetic bearing consumes electric energy, the power consumption and the heat generation are large, and the adverse effect on the system is generated particularly in a low-temperature environment.
The air bearing has the advantages of no mechanical friction, no loss, no pollution, high rotation precision and the like, and can work in high-temperature and low-temperature environments. But the air bearing has poor stability, strong friction and wear at the start-stop and low-speed stages and smaller bearing capacity.
The magnetic-air hybrid bearing combines a magnetic bearing and an air bearing, uses the air bearing to bear main load, and uses the controllability of the magnetic bearing to control a shafting through feedback and compensation, thereby achieving the purposes of high bearing and high precision. The magnetic and air hybrid bearing combines the advantages of the magnetic and air bearings, and has more excellent comprehensive performance. The magnetic bearing works at the starting and low-speed stage, so that the starting and stopping friction and abrasion problems of the air bearing are solved, and the bearing capacity of the bearing system is improved; after the rotor reaches the working rotation speed and stably runs, the air bearing plays a main bearing role, and the power consumption and the heating of the magnetic bearing are reduced.
Magnetic bearings and gas bearings have their own advantages and disadvantages as two typical high speed support means. The two types of the bearing are combined to form complementary advantages, so that the bearing capacity of the bearing can be improved, the dynamic performance of the system can be improved, and the load distribution between the two types of the bearing can be realized. When the magnetic bearing suddenly fails, the air bearing can also serve as a protection bearing, and is an ideal supporting mode of the high-speed rotating machine.
For the magnetic-air hybrid bearing, because the working principles of the magnetic and air bearings are different, the air gap required by the work of the air bearing is small, and the air gap required by the work of the magnetic bearing is large. Thus, in some cases, there may be a case where rubbing of the rotor with the gas bearing occurs. For example, when the magnetic bearing works, the amplitude of the motion track of the rotor controlled by the magnetic bearing is larger than the radius clearance of the air bearing, and particularly for the occasion needing frequent start and stop, the dynamic pressure effect of the air bearing is not formed at the start stage, and the rotor has larger amplitude when passing through the critical rotating speed, so that the air bearing bush needs to be replaced frequently due to the collision between the rotor and the air bearing under the conditions.
At present, the magnetic-air hybrid bearing is mainly divided into two main types of parallel structures and nested structures in structure. The US 6,353,273B1 patent adopts a nested structure to embed the foil gas bearing into the inner surface of the magnetic pole of the magnetic bearing, and proposes a load distribution method for adjusting the magnetic bearing and the foil gas bearing according to the change of the rotation speed. CN200510041540.5 patent invents an electromagnetic-cantilever type foil hybrid bearing, embedding a cantilever type foil gas bearing into the inner surface of the electromagnetic bearing. The CN202010400181.2 patent discloses an electromagnetic-herringbone groove dynamic pressure hybrid bearing, and a wedge-shaped herringbone groove is formed in the inner wall of a radial electromagnetic bearing, so that a dynamic pressure air film is formed in the running process of a rotor, and the dynamic characteristic of a system is improved.
The parallel structure is to place the magnetic bearing and the air bearing along the axial direction of the rotating shaft. The CN202011404910.8 patent discloses an electromagnetic-foil hybrid bearing, wherein an electromagnetic bearing and a foil gas bearing are independently and parallelly arranged in the axial direction of a rotating shaft. Under the condition of ensuring that the axial length and the nominal air gap of the electromagnetic bearing are unchanged, the CN201010120072.1 integrates two foil bearings on two sides of the magnetic pole of the electromagnetic bearing, thereby shortening the rotor span.
The nested structure can shorten the size of the rotating shaft, but the structure is complex. The parallel structure is simple, but the length of the rotor is increased, and the dynamic performance of the system is reduced. The above patent does not solve the problem of high control accuracy requirement for the electromagnetic bearing caused by different working gap dimensions of the electromagnetic bearing and the gas bearing.
Therefore, the mutual conversion between the elastic support and the rigid support of the air bearing is effectively realized, the serious friction and abrasion of the air bearing caused by insufficient control precision of the magnetic bearing is avoided, and the method is particularly important for the application of the magnetic and air hybrid support.
Disclosure of Invention
In order to solve the problems, the invention provides a magnetic-air hybrid bearing with a mutually-converted rigid support and elastic support, which adopts a special mechanical structure, is mainly carried by the magnetic bearing in the starting and stopping stage, the low-speed stage or the overload stage of a rotating shaft, and has the elastic support, so that the friction and abrasion of a rotor and a bearing bush can be reduced; after the rotating shaft runs stably, the bearing is mainly carried by the air bearing, and the air bearing has rigid support, so that the carrying capacity of the air bearing can be improved. The invention can improve the friction and abrasion problems of the dynamic pressure gas bearing caused by frequent start and stop of the rotor system, prolong the service life of the bearing, reduce the heating and power consumption of the magnetic bearing and obtain excellent comprehensive performance of the bearing.
In order to solve the above-mentioned purpose, the technical scheme provided by the invention is as follows:
A magnetic-air hybrid bearing with interconversion of rigid support and elastic support comprises a fixed frame, an air inlet channel, a wedge-shaped gasket, a spring, elastic rubber, a bearing bush, a rotor, a magnetic-air hybrid bearing controller, a power amplifier and a displacement sensor,
The magnetic bearing comprises magnetic bearing poles, magnetic pole coils and a displacement sensor in the axial direction, wherein the magnetic bearing poles are wound by the magnetic pole coils, the displacement sensor is arranged between the magnetic pole coils and the magnetic bearing, a nominal air gap of the magnetic bearing is reserved between the magnetic bearing poles and the rotor, the magnetic pole coils are connected with a power amplifier, and the power amplifier and the displacement sensor are both connected with a magnetic-air hybrid bearing controller;
The radial outside of air bearing is supported by the mount, the mount contains outer lane and inner circle, and the mount outer lane is the mount ring, and the mount inner circle is mount wedge slot, and mount wedge slot contains bottom wedge slot and top rectangular channel, and the rotor is installed at the ring center that mount wedge slot is located, sets up air bearing bush and elastic rubber between mount wedge slot and the rotor, and air bearing bush comprises bearing bush ring and the horizontal handle of bearing bush, the horizontal handle of bearing bush ring rigid coupling bearing bush, and the horizontal handle of bearing bush is arranged in the top rectangular channel of mount wedge slot in, sets up the inlet channel between the horizontal handle top surface of bearing bush and the top rectangular channel, sets up wedge gasket between the horizontal handle side of bearing bush and the top rectangular channel, sets up the spring between the horizontal handle bottom surface of bearing bush and the top rectangular channel.
And a radial clearance of the air bearing is reserved between the rotor and the bearing bush ring.
The elastic rubber wraps the bearing bush circular ring on the radial outer ring.
The rotor is axially provided with a protection bearing, the protection bearing and the air bearing are respectively positioned at two sides of the magnetic bearing, and a radius clearance of the protection bearing is reserved between the protection bearing and the rotor.
The groove opening of the wedge-shaped groove of the fixing frame is opposite to the bearing bush transverse handle, and the protruding blocks arranged at the bottom of the bearing bush circular ring and opposite to the bearing bush transverse handle can enter the groove.
The magnetic hybrid bearing works in a magnetic bearing mode in the starting stage, the low-speed stage or overload stage of the rotating shaft, and the air bearing has elastic support at the moment;
after the rotor runs stably, the rotor works in an air bearing mode, and the air bearing has a rigid support;
When an air inlet channel at the top of the transverse handle of the rigid bearing bush is opened, pressure air is introduced to push the rigid bearing bush to move downwards until a lug at the bottom of the bearing bush enters a wedge-shaped groove at the bottom of the fixing frame, and at the moment, the freedom degrees of the rigid bearing bush in all directions are limited, so that a rigid support is formed, and the conversion from an elastic support to the rigid support of the magnetic-air hybrid bearing is realized;
When the air inlet channel stops feeding pressure air, the pressurized air fed before is discharged, the compressed spring below the bearing bush transverse handle gradually returns to the original state, and the rigid bearing bush transverse handle is pushed to move upwards, so that the whole bearing bush moves upwards and is separated from a bottom groove area, and the conversion from rigid support to elastic support of the magnetic-air hybrid bearing is realized.
The working process of the hybrid bearing is as follows:
s1, starting and low-speed stages:
The magnetic bearing bears load, the air bearing bush transverse handle is supported by the compression spring, and the bush freely moves in the cavity along with the movement of the rotor, and the elastic rubber plays a role in buffering and protecting;
S2, a stable working stage:
when the rotor reaches the rated working rotation speed and stably runs, the conversion from the magnetic bearing to the air bearing is realized;
S3, stopping:
The conversion from the air bearing to the magnetic bearing is realized.
The conversion process from the magnetic bearing to the air bearing in the step S2 is as follows:
Firstly, reducing the current of a magnetic pole coil, reducing the electromagnetic force, reducing the gravity center of a rotor, forming a certain eccentricity, and driving an air lubricating film to generate dynamic pressure effect by a rotor rotating at a high speed;
Then, with the increase of the eccentricity of the rotor, the bearing capacity of the air bearing is larger and larger, the air bearing is used as a main support gradually, and at the moment, the air inlet channel at the top of the air bearing bush transverse handle is opened to input pressurized air, and the pressure of the pressurized air is more than or equal to the pressure required by pushing the bush to enter the wedge-shaped groove of the fixing frame and fixing and locking, so that the rigid air bearing is formed, the conversion from the magnetic bearing to the air bearing is realized, and the conversion from the elastic support to the rigid support is also realized.
The method for reducing the magnetic pole coil current in the step S2 is one or a combination of the following two methods:
The pole coil current is reduced by reducing the magnetic bearing control parameters,
Reducing the magnetic pole coil current by reducing the magnetic bearing bias current;
Wherein the minimum current allowed by the pole coils creates electromagnetic forces that levitate the rotor and do not contact the protective bearing.
The moment of inputting pressurized gas into the air inlet channel at the top of the air bearing bush transverse handle is determined by the following method:
The load ratio of the magnetic bearing and the air bearing is preset according to the actual working condition, and the preset eccentricity e is calculated according to the preset load of the air bearing. In the process of reducing the current of the magnetic pole coil, the eccentricity of the rotor is continuously increased, and when the preset eccentricity e is reached, an air inlet channel at the top of a transverse handle of the air bearing bush is opened at the moment to input pressurized air, so that the conversion from the magnetic bearing to the air bearing is realized.
The conversion process from the air bearing to the magnetic bearing in the step S3 is as follows:
the air inlet channel stops to be filled with pressurized gas, the pressurized gas filled before is discharged, the compressed spring is restored to deform, the air bearing bush transverse handle is pushed to move upwards in the original length restoring process, the bush transverse handle drives the bush circular ring to move upwards, the eccentric distance of the rotor is reduced, the bearing capacity of the air bearing is smaller and smaller, the protruding block at the bottom of the bush circular ring leaves the wedge-shaped groove of the fixing frame, so that an elastic air bearing is formed, and the air bearing is converted from rigid support to elastic support while the air bearing is converted to magnetic bearing.
In the turbine expander system, the magnetic bearing and the cylindrical surface rigid gas bearing are adopted to cooperatively use, so that a certain necessity is provided, and a novel structure with the switchable elastic gas bearing and the rigid gas bearing is adopted, so that the cooperative use of the magnetic and gas hybrid bearing is realized, the problem of frequent replacement of the gas bearing is improved, and meanwhile, the performance index requirement on a magnetic bearing hardware system is reduced, so that the manufacturing cost of the magnetic and gas hybrid bearing is reduced.
Compared with the prior art, the technical scheme has at least the following beneficial effects:
Magnetic bearings and gas bearings have their own advantages and disadvantages as two typical high speed support means. The two types of the bearing are combined to form complementary advantages, so that the bearing capacity of the bearing can be improved, the dynamic performance of the system can be improved, and the load distribution between the two types of the bearing can be realized. The air bearing can also act as a protective bearing when the magnetic bearing suddenly fails, and is an ideal support. The scheme can realize that the air bearing has elastic supporting rigidity when the magnetic bearing bears in the starting and low-speed stages, and becomes a rigid surface air bearing and bears main load after the air dynamic pressure effect is formed when the rotor reaches the stable rotating speed. According to the scheme, the friction and abrasion problem caused by frequent start and stop of the dynamic pressure gas bearing can be solved, the service life of the bearing is prolonged, the heating and power consumption of the magnetic bearing are reduced, the excellent comprehensive performance of the bearing is obtained, the performance index requirement on a hardware system of the magnetic bearing is reduced, and therefore the manufacturing cost of the magnetic gas hybrid bearing is reduced.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a magnetic hybrid bearing system with a rigid support and a flexible support that are switched between each other in accordance with the present invention;
FIG. 2 is a partial schematic view of an air bearing wedge gasket and air inlet passage of the present invention;
FIG. 3 is a partial schematic view of a wedge groove of an air bearing of the present invention;
FIG. 4 is a schematic diagram of an air bearing-rotor system for a start-up procedure in an embodiment of the invention;
FIG. 5 is a schematic diagram of a steady operation gas bearing-rotor system and gas pressure requirements in an embodiment of the present invention;
FIG. 6 is a schematic diagram of an air bearing-rotor system for a shutdown process in accordance with an embodiment of the present invention;
fig. 7 is an axial distribution diagram of a magnetic hybrid bearing according to the present invention.
Wherein: 1 a-a circular ring of a fixing frame; 1 b-a wedge-shaped groove of a fixing frame; 2-an intake passage; 3-wedge-shaped gaskets; 4-a spring; 5-elastic rubber; 6-radial clearance of the air bearing; 7 a-a bearing bush transverse handle; 7 b-a bearing bush ring; 8-a rotor; 9-a magnetic hybrid bearing controller; a 10-power amplifier; 11-magnetic bearing poles; 12-pole coils; 13-nominal air gap of magnetic bearing; 14-gas bearings; 15-a displacement sensor; 16-protecting the bearing; 17-protecting bearing radius gap.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. It will be apparent that the described embodiments are some, but not all, embodiments of the invention. All other embodiments, which can be made by a person skilled in the art without creative efforts, based on the described embodiments of the present invention fall within the protection scope of the present invention.
Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. It should be noted that "upper", "lower", "left", "right", "front", "rear", and the like are used in the present invention only to indicate a relative positional relationship, and when the absolute position of the object to be described is changed, the relative positional relationship may be changed accordingly.
The invention provides a magnetic-air hybrid bearing with a mutually-converted rigid support and an elastic support.
As shown in fig. 1 and 7, the magnetic hybrid bearing comprises a fixed frame, an air inlet channel 2, a wedge-shaped gasket 3, a spring 4, elastic rubber 5, a bearing bush, a rotor 8, a magnetic hybrid bearing controller 9, a power amplifier 10 and a displacement sensor 15,
The magnetic bearing is characterized in that a protection bearing 16, a magnetic bearing and a gas bearing 14 are sequentially arranged along the axial direction of the rotor 8 from left to right, a magnetic bearing magnetic pole 11, a magnetic bearing coil 12 and a displacement sensor 15 are axially arranged on the rotor 8, the magnetic bearing magnetic pole 11 is wound by the magnetic bearing coil 12, a displacement sensor 15 is arranged between the magnetic pole coil 12 and the gas bearing 14, the protection bearing 16 is arranged on the other side of the magnetic pole coil 12, a magnetic bearing nominal air gap 13 is arranged between the magnetic bearing magnetic pole 11 and the rotor 8, a protection bearing radius gap 17 is reserved between the protection bearing 16 and the rotor 8, a gas bearing radius gap 6 is reserved between the gas bearing 14 (a gas bearing bush circular ring 7 b) and the rotor 8, the magnetic pole coil 12 is connected with a power amplifier 10, and the power amplifier 15 is connected with a magnetic gas hybrid bearing controller 9; the protection bearing is used for protecting the magnetic bearing when the power is off or the magnetic bearing fails, and because the air bearing can also be used as the protection bearing of the magnetic bearing, the protection bearing can be installed or not according to actual conditions, and the protection bearing is designed and installed in the embodiment;
The radial outside of the air bearing 14 is supported by a fixing frame, the fixing frame comprises a fixing frame outer ring and a fixing frame inner ring, the fixing frame outer ring is a fixing frame circular ring 1a, the fixing frame inner ring is a fixing frame wedge groove 1b, the fixing frame wedge groove comprises a bottom wedge groove and a top rectangular groove, a rotor 8 is arranged in the center of the circular ring where the fixing frame wedge groove 1b is located, an air bearing bush bearing ring 7b and elastic rubber 5 are arranged between the rotor 8 and the fixing frame wedge groove 1b, the air bearing bush comprises an air bearing bush ring 7b and an air bearing bush transverse handle 7a, the air bearing bush ring 7b is fixedly connected with the air bearing bush transverse handle 7a, the air bearing bush transverse handle 7a is arranged in the top rectangular groove of the fixing frame wedge groove 1b, an air inlet channel 2 is arranged between the top surface of the air bearing bush transverse handle 7a and the top rectangular groove, a wedge gasket 3 is arranged between the side surface of the air bearing bush transverse handle 7a and the top rectangular groove (as shown in figure 2), and a spring 4 is arranged between the bottom surface of the air bearing bush transverse handle 7a and the top rectangular groove.
As shown in fig. 1, an air bearing radius gap 6 is left between the rotor 8 and the bushing ring 7 b.
The elastic rubber 5 wraps the bush ring 7b radially on the outer ring.
As shown in fig. 3, the fixing frame is provided with a groove with a wedge-shaped opening, the groove is opposite to the bottom lug of the circular ring of the bearing bush, and the bottom lug of the circular ring of the bearing bush can enter the groove.
The hybrid bearing works in a magnetic bearing mode in a rotating shaft starting stage, a low-speed stage or overload state, and the air bearing has elastic support at the moment;
after the rotor runs stably, the rotor works in an air bearing mode, and the air bearing has a rigid support;
When an air inlet channel at the top of the transverse handle of the rigid bearing bush is opened, pressure air is introduced to push the rigid bearing bush to move downwards until a lug at the bottom of the circular ring of the bearing bush enters a wedge-shaped groove at the bottom of the fixing frame, and at the moment, the freedom degrees of the rigid bearing bush in all directions are limited, so that a rigid support is formed, and the conversion from an elastic support to a rigid support of the magnetic-air hybrid bearing is realized;
When the pressure gas is not fed into the air inlet channel, the pressurized gas fed in before is discharged, the compressed spring below the bearing bush transverse handle gradually returns to the original state, and the rigid bearing bush transverse handle is pushed to move upwards, so that the whole bearing bush moves upwards and is separated from the bottom groove area, and the conversion from rigid support to elastic support of the magnetic-air hybrid bearing is realized.
Specifically, the working process of the hybrid bearing is as follows:
s1, starting and low-speed stages:
the magnetic bearing is used for bearing load, the air bearing bush transverse handle is supported by the compression spring, and the bearing bush moves freely in the cavity along with the movement of the rotor, and the elastic rubber plays a role in buffering and protecting, as shown in fig. 4;
S2, a stable working stage:
when the rotor reaches the rated working rotation speed and stably runs, the conversion from the magnetic bearing to the air bearing is realized; as shown in fig. 5, the air inlet channel inputs pressurized air to push the bearing bush to enter the wedge-shaped groove at the bottom of the fixing frame and to be fixedly locked, so that a rigid air bearing is formed;
At this time, the minimum pressure of the introduced gas is as follows
Wherein P is the minimum pressure of the gas introduced,
F is spring pressure, the size of the F is just capable of pushing the bearing bush to enter the wedge-shaped groove at the bottom of the fixing frame and is fixedly locked,
K is the stiffness coefficient of the spring,
H is the elastic deformation of the spring, the size of the elastic deformation is equal to the descending height of the lug at the bottom of the circular ring of the bearing bush in the groove,
S is the area of the upper surface of the bearing bush transverse handle acted by the pressure gas.
S3, stopping:
The transition from the gas bearing to the magnetic bearing is achieved, as in fig. 6, the gas supply is stopped, the spring resumes its deformation, and the bearing shell leaves the bottom wedge-shaped region, thus forming an elastic gas bearing.
The conversion process from the magnetic bearing to the air bearing in the step S2 is as follows:
Firstly, reducing the current of a magnetic pole coil, reducing the electromagnetic force, reducing the gravity center of a rotor, forming a certain eccentricity, and driving an air lubricating film to generate dynamic pressure effect by a rotor rotating at a high speed;
with the increase of the eccentricity of the rotor, the bearing capacity of the air bearing is larger and larger, the air bearing is used as a main support gradually, the air inlet channel at the top of the transverse handle of the air bearing bush is opened at the moment to input pressurized air, and the pressure of the pressurized air is more than or equal to the pressure required by pushing the bush to enter the wedge-shaped groove of the fixing frame and fixing and locking, so that the rigid air bearing is formed, the conversion from the magnetic bearing to the air bearing is realized, and the conversion from the elastic support to the rigid support of the air bearing is also realized.
Wherein, the method for reducing the current of the magnetic pole coil selects one or the combination of the two of the following two methods:
reducing magnetic pole coil current by reducing magnetic bearing control parameters;
reducing the magnetic pole coil current by reducing the magnetic bearing bias current;
The method for reducing the magnetic pole coil current can be any one or the combination of the two, and the maximum amplitude of the rotor is less than or equal to A in the process of adjusting the magnetic bearing coil current, wherein A is a set amplitude, and the value of the A is determined according to the actual working condition. The electromagnetic force generated by the minimum current allowed by the magnetic pole coil is ensured to suspend the rotor and not contact with the protection bearing.
The moment of inputting pressurized gas into the air inlet channel at the top of the air bearing bush transverse handle is determined by the following method:
The load ratio of the magnetic bearing and the air bearing is preset according to the actual working condition, and the preset eccentricity e is calculated according to the preset load of the air bearing. In the process of reducing the current of the magnetic pole coil, the eccentricity of the rotor is continuously increased, and when the preset eccentricity e is reached, an air inlet channel at the top of a transverse handle of the air bearing bush is opened to input pressurized air, so that the conversion from the magnetic bearing to the air bearing is realized.
The conversion process from the air bearing to the magnetic bearing in the step S3 is as follows:
the air inlet channel stops to be filled with pressurized gas, the pressurized gas filled before is discharged, the compressed spring is restored to deform, the air bearing bush transverse handle is pushed to move upwards in the original length restoring process, the bush transverse handle drives the bush circular ring to move upwards, the eccentric distance of the rotor is reduced, the bearing capacity of the air bearing is smaller and smaller, the protruding block at the bottom of the bush circular ring leaves the wedge-shaped groove of the fixing frame, so that an elastic air bearing is formed, and the air bearing is converted from rigid support to elastic support while the air bearing is converted to magnetic bearing.
The following points need to be described:
(1) The drawings of the embodiments of the present invention relate only to the structures related to the embodiments of the present invention, and other structures may refer to the general designs.
(2) The embodiments of the invention and the features of the embodiments can be combined with each other to give new embodiments without conflict.
The present invention is not limited to the above embodiments, but the scope of the invention is defined by the claims.
Claims (10)
1. A magnetic-air hybrid bearing with interconversion of a rigid support and an elastic support is characterized by comprising a fixed frame, an air inlet channel, a wedge-shaped gasket, a spring, elastic rubber, a bearing bush, a rotor, a magnetic-air hybrid bearing controller, a power amplifier and a displacement sensor,
The magnetic bearing comprises magnetic bearing poles, magnetic pole coils and a displacement sensor in the axial direction, wherein the magnetic bearing poles are wound by the magnetic pole coils, the displacement sensor is arranged between the magnetic pole coils and the magnetic bearing, a magnetic bearing nominal air gap is arranged between the magnetic bearing poles and the rotor, the magnetic pole coils are connected with a power amplifier, and the power amplifier and the displacement sensor are both connected with a magnetic-air hybrid bearing controller;
The radial outside of air bearing is supported by the mount, the mount contains outer lane and inner circle, and the mount outer lane is the mount ring, and the mount inner circle is mount wedge slot, and mount wedge slot contains bottom wedge slot and top rectangular channel, and the rotor is installed at the ring center that mount wedge slot is located, sets up elastic rubber and air bearing axle bush between mount wedge slot and the rotor, the air bearing axle bush comprises axle bush ring and the horizontal handle of axle bush, the horizontal handle of axle bush rigid coupling axle bush, and in the top rectangular channel of mount wedge slot was arranged in to the horizontal handle of axle bush, set up the inlet channel between the horizontal handle top surface of axle bush and the top rectangular channel, set up wedge gasket between the horizontal handle side of axle bush and the top rectangular channel, set up the spring between the horizontal handle bottom surface of axle bush and the top rectangular channel.
2. The magnetic and air hybrid bearing with interconversion of rigid support and elastic support according to claim 1, characterized in that an air bearing radius gap is left between the rotor and the bushing ring;
The elastic rubber wraps the bearing bush circular ring on the radial outer ring.
3. The magnetic and air hybrid bearing with interconversion of rigid support and elastic support according to claim 1, wherein the rotor shaft is provided with a protection bearing, and the protection bearing and the air bearing are respectively positioned at two sides of the magnetic bearing; a radial clearance of the protection bearing is reserved between the protection bearing and the rotor.
4. The magnetic-air hybrid bearing with the interconversion of the rigid support and the elastic support according to claim 1, wherein the groove opening of the wedge-shaped groove of the fixing frame is opposite to the bearing bush transverse handle, and the protruding block arranged at the bottom of the bearing bush circular ring opposite to the bearing bush transverse handle can enter the groove.
5. The magnetic hybrid bearing with interconversion of rigid support and elastic support according to claim 1, wherein the air bearing is operated in a magnetic bearing mode during a start-up phase, a low-speed phase or an overload of the rotating shaft, in which case the air bearing has an elastic support;
after the rotor runs stably, the rotor works in an air bearing mode, and the air bearing has a rigid support;
When an air inlet channel at the top of the transverse handle of the rigid bearing bush is opened, pressure air is introduced to push the rigid bearing bush to move downwards until a lug at the bottom of the bearing bush enters a wedge-shaped groove at the bottom of the fixing frame, and at the moment, the freedom degrees of the rigid bearing bush in all directions are limited, so that a rigid support is formed, and the conversion from an elastic support to the rigid support of the magnetic-air hybrid bearing is realized;
When the air inlet channel stops feeding pressure air, the pressurized air fed before is discharged, the compressed spring below the bearing bush transverse handle gradually returns to the original state, and the rigid bearing bush transverse handle is pushed to move upwards, so that the whole bearing bush moves upwards and is separated from a bottom groove area, and the conversion from rigid support to elastic support of the magnetic-air hybrid bearing is realized.
6. The magnetically levitated hybrid bearing of claim 1, wherein the hybrid bearing operates as follows:
s1, starting and low-speed stages:
The magnetic bearing bears load, the air bearing bush transverse handle is supported by the compression spring, and the bush freely moves in the cavity along with the movement of the rotor, and the elastic rubber plays a role in buffering and protecting;
S2, a stable working stage:
when the rotor reaches the rated working rotation speed and stably runs, the conversion from the magnetic bearing to the air bearing is realized;
S3, stopping:
The conversion from the air bearing to the magnetic bearing is realized.
7. The magnetic hybrid bearing with interconversion of rigid support and elastic support according to claim 6, wherein the process of converting the magnetic bearing into the air bearing in step S2 is as follows:
Firstly, reducing the current of a magnetic pole coil, reducing the electromagnetic force, reducing the gravity center of a rotor, forming eccentricity, and driving an air lubricating film to generate dynamic pressure effect by a rotor rotating at a high speed;
Then, with the increase of the eccentricity of the rotor, the bearing capacity of the air bearing is larger and larger, the air bearing is gradually taken as a main support, and at the moment, the air inlet channel at the top of the air bearing bush transverse handle is opened to input pressurized air, and the pressure of the pressurized air is more than or equal to the pressure required by pushing the bush to enter the wedge-shaped groove of the fixing frame and fixing and locking, so that the rigid air bearing is formed, the conversion from the magnetic bearing to the air bearing is realized, and the conversion from the elastic support to the rigid support is also realized.
8. The magnetically levitated and elastically supported interconverted magnetic hybrid bearing of claim 7, wherein the method of reducing the pole coil current is one or a combination of two of:
The pole coil current is reduced by reducing the magnetic bearing control parameters,
Reducing the magnetic pole coil current by reducing the magnetic bearing bias current;
The minimum current allowed by the pole coils creates electromagnetic forces that levitate the rotor and do not contact the protective bearing.
9. The magnetic and air hybrid bearing with interconversion of rigid support and elastic support according to claim 7, wherein the moment of opening the air inlet channel at the top of the air bearing shell cross-shank to let in the pressurized air is determined by the following method:
The load ratio of the magnetic bearing and the air bearing is preset according to the actual working condition, the preset eccentricity e is calculated according to the preset load of the air bearing, the eccentricity of the rotor is continuously increased in the process of reducing the current of the magnetic pole coil, and when the preset eccentricity e is reached, an air inlet channel at the top of a transverse handle of the air bearing bush is opened to input pressurized air, so that the magnetic bearing is converted into the air bearing.
10. The magnetic hybrid bearing with interconversion of rigid support and elastic support according to claim 6, wherein the process of converting the air bearing into the magnetic bearing in step S3 is as follows:
The air inlet channel stops to let in pressurized gas, simultaneously unloads the pressurized gas that lets in before, and compressed spring resumes deformation, promotes the upward movement of gas bearing axle bush horizontal handle at the long in-process of recovering, and axle bush horizontal handle drives the axle bush ring and reciprocates, and the eccentric distance of rotor reduces, and the bearing capacity of gas bearing is less and less, and axle bush ring bottom lug leaves the mount wedge slot to form elasticity gas bearing, when realizing that gas bearing changes to the magnetic bearing, gas bearing also realizes by rigid support to elastic support's conversion.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101326378A (en) * | 2005-12-09 | 2008-12-17 | Ntn株式会社 | Motor integrated magnetic bearing device |
| CN112564380A (en) * | 2020-11-27 | 2021-03-26 | 珠海格力电器股份有限公司 | Bearing protection device, magnetic suspension bearing and system thereof |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6965181B1 (en) * | 1997-09-15 | 2005-11-15 | Mohawk Innovative Technology, Inc. | Hybrid foil-magnetic bearing with improved load sharing |
| US6608418B2 (en) * | 2001-08-24 | 2003-08-19 | Smiths Aerospace, Inc. | Permanent magnet turbo-generator having magnetic bearings |
| CN1730959A (en) * | 2005-08-19 | 2006-02-08 | 南京航空航天大学 | Magnetic-gas bearing and method for making compliant foil |
| CN108868892B (en) * | 2018-01-12 | 2024-04-02 | 刘慕华 | Rotor system and control method thereof, gas turbine generator set and control method thereof |
| CN113864337A (en) * | 2021-10-22 | 2021-12-31 | 山西特博优新能源科技有限公司 | Homopolar gas-magnetic double-field dynamic pressure radial hybrid bearing |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101326378A (en) * | 2005-12-09 | 2008-12-17 | Ntn株式会社 | Motor integrated magnetic bearing device |
| CN112564380A (en) * | 2020-11-27 | 2021-03-26 | 珠海格力电器股份有限公司 | Bearing protection device, magnetic suspension bearing and system thereof |
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