CN204371940U - A kind of annular poles structure and there is the axial magnetic bearing of annular poles structure - Google Patents
A kind of annular poles structure and there is the axial magnetic bearing of annular poles structure Download PDFInfo
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- CN204371940U CN204371940U CN201520004699.9U CN201520004699U CN204371940U CN 204371940 U CN204371940 U CN 204371940U CN 201520004699 U CN201520004699 U CN 201520004699U CN 204371940 U CN204371940 U CN 204371940U
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Abstract
The utility model discloses a kind of annular poles structure and there is the axial magnetic bearing of annular poles structure, comprising: inner side magnetic pole unshakable in one's determination and outside magnetic pole; Described inner side magnetic pole is cylindric, and outside magnetic pole is cylindric, and inner side magnetic pole is arranged on the inside of outside magnetic pole; The end face of described inner side magnetic pole and outside magnetic pole has at least an end face to have at least one circle groove, and described groove forms donut structure on magnetic pole face, interior outside.The utility model beneficial effect: after adopting annular poles, radial force and the radial rigidity of axial magnetic bearing are obviously strengthened; Inner side magnetic pole can be selected to adopt ring structure, outside magnetic pole to adopt ring structure or interior outside magnetic pole to adopt the different structures such as ring structure, the radial force of regulation and control axial magnetic bearing and radial rigidity simultaneously.
Description
Technical field
The utility model relates to a kind of magnetic bearing structure, particularly a kind of annular poles structure and have the axial magnetic bearing of annular poles structure.
Background technique
Magnetic suspension bearing be by rotor between magnetic force, supporting rotor is suspended in the Novel electromechanical integration bearing of space desired location.Due between its rotor and stator without any Mechanical Contact, therefore without wearing and tearing, greatly reduce mechanical energy consumption and noise, and without the need to lubrication, without oil pollution, long service life, be applicable to the particular surroundingss such as high speed, vacuum.In recent years, magnetic suspension bearing is successfully applied to the equipment such as lathe, centrifugal compressor, vacuum molecular pump, artificial heart in the world.
Tradition suspension of five-freedom degree magnetic bearing arrangement is made up of two groups of radial direction magnetic bearings and one group of axial magnetic bearing, control radial four translational degree of freedom and an axial translational degree of freedom respectively, often organize magnetic bearing and all pass through the devices such as displacement transducer, controller and power amplifier in each degrees of freedom, realize closed loop control, magnetic force needed for the suspension of respective degrees of freedom is provided, realizes rotor five-degree magnetic suspension in space.Tradition suspension of five-freedom degree magnetic system shortcoming is that volume is comparatively large, and power consumption is high.Certain single-degree-of-freedom magnetic bearing provides the magnetic suspension system of multi-freedom degree bearing capacity, can reduce the degrees of freedom of ACTIVE CONTROL, reduces system power dissipation and volume.
The radial bearing capacity of conventional axial magnetic bearing is less, provides in the system of radial suspension force at axial magnetic bearing, and radial direction is difficult to bear large perturbed force; Radial rigidity is low, is difficult to get back to equilibrium position rapidly after radial direction is subjected to displacement.Its physical cause is field structure, and inner side is circular flat, and outside magnetic pole is single ring plain, when occur radial displacement time, in air-gap flux, axial magnetic flux ratio is higher, and radial flux component is less, therefore cause radial force and radial rigidity less.Radial bearing capacity directly determines the radial suspension performance of magnetic bearing system, and improving the radial bearing capacity and stiffness of axial magnetic bearing, is the key that axial magnetic bearing realizes single-degree-of-freedom ACTIVE CONTROL magnetic suspension system.
Model utility content
The purpose of this utility model is exactly to solve the problems of the technologies described above, provide a kind of annular poles structure and there is the axial magnetic bearing of annular poles structure, adopt annular poles structure, make in the air-gap field between axial magnetic bearing magnetic pole, magnetic flux axial component ratio reduces, magnetic flux radial component ratio increases, thus reaches the object improving axial magnetic bearing radial force and radial rigidity.
To achieve these goals, the utility model adopts following technological scheme:
A kind of annular poles structure, comprising: inner side magnetic pole unshakable in one's determination and outside magnetic pole; Described inner side magnetic pole is cylindric, and outside magnetic pole is cylindric, and inner side magnetic pole is arranged on the inside of outside magnetic pole; The same side end face of described inner side magnetic pole and outside magnetic pole has at least an end face to have at least one circle groove, and described groove forms donut structure on magnetic pole face, interior outside.
Described iron core is stator core, and the field structure of the rotor core relative with described stator core magnetic pole is identical with described stator core field structure, and inner side magnetic pole is identical with the donut physical dimension of outside magnetic pole end face;
By magnetic induction intensity and the Magnetic field distribution of annular poles structural change stator and rotor cores air-gap field, thus strengthen the radial forces between stator core and rotor core.
A kind of axial magnetic bearing with annular poles structure, it is characterized in that, comprise magnetic suspension rotor, the axial two ends along described magnetic suspension rotor arrange the axial magnetic bearing for providing rotor axial suspending power and radial suspension force respectively, and the axial magnetic bearing at described rotor axial two ends is symmetrically distributed;
Described magnetic suspension rotor magnetic pole unshakable in one's determination and stator core is annular poles structure, and the magnetic pole of rotor core and stator core is positioned opposite, field structure and inner side magnetic pole all identical with the donut physical dimension of outside magnetic pole end face.
By controlling the magnetic flux at air gap place between both sides axial magnetic bearing and rotor, producing axial restoring force, making rotor axially keep stable suspersion initiatively;
When there is a certain radial displacement in rotor, electromagnetic force between axial magnetic bearing and rotor will produce radial component, and described radial component direction is contrary with rotor radial direction of displacement, point to axle center, described radial component makes rotor get back to radial equilibrium position, thus keeps the radial suspension of rotor;
When radially small angular variation occurs axle rotor, the radial component of described both sides axial magnetic bearing produces a restoring moment, makes rotor get back to equilibrium position.
Arrange shaft position sensor respectively at described rotor axial or radial direction, described shaft position sensor is connected with controller, and described controller is connected respectively by the coil of power amplifier with magnetic suspension rotor axial two ends axial magnetic bearing.
When described shaft position sensor is arranged on rotor radial, rotor is arranged the permanent-magnetic clamp for providing sensor signal source, permanent-magnetic clamp adopts axial charging, and permanent-magnetic clamp position and sensor are in same axial position.
If rotor radial selects driven suspension, then do not need radial displacement transducer is installed;
If rotor radial needs ACTIVE CONTROL, then need at the radial displacement transducer of rotor radial installation for measuring rotor radial displacement, radial displacement transducer has four, be arranged in outside rotor, be divided into two groups, often organize two sensors and become 90 degree of at right angle settings, radial displacement is detected.
Described axial magnetic bearing is electromagnetic bearing or electromagnet and permanent magnet hybrid magnetic bearing.
The utility model beneficial effect:
(1), after adopting annular poles, radial force and the radial rigidity of axial magnetic bearing are obviously strengthened; Inner side magnetic pole can be selected to adopt ring structure, outside magnetic pole to adopt ring structure or interior outside magnetic pole to adopt the different structures such as ring structure, the radial force of regulation and control axial magnetic bearing and radial rigidity simultaneously.
(2) the utility model structure is simple, only need utilize mechanical processing technique at magnetic pole place, magnetic pole strength is processed into polycyclic structures, all the other structures and traditional magnetic bearing structure basically identical, or multi-annular field structure is applied in axial magnetic bearing structure of the present utility model, utilize the radial force of axial magnetic bearing, as rotor radial suspending power, thus eliminate radial direction magnetic bearing.
(3) when there is radial displacement, this arrangement reduces the ratio of axial magnetic flux between magnetic pole, adding the ratio of radial flux between magnetic pole, thus the radial force between stator and rotor is increased.
(4) research shows, can be changed axial force and the radial force of axial magnetic bearing by the radial thickness changing annular poles.For axially different and radial load, only can change annular poles parameter, change axial magnetic bearing axially with radial suspension characteristic.
(5) magnetic suspension system ACTIVE CONTROL degrees of freedom is reduced to minimum by axial magnetic bearing structure of the present utility model, eliminate the parts such as controller, power amplifier, electromagnetic coil needed for the control of unnecessary active degrees of freedom, simplify suspension of five-freedom degree magnetic bearing support structure.
Accompanying drawing explanation
Fig. 1 is that the utility model annular poles is for axial magnetic bearing system architecture schematic diagram;
Fig. 2 is the utility model annular poles axial magnetic bearing stator faces figure;
Fig. 3 is the utility model annular poles axial magnetic bearing rotor end view drawing;
Fig. 4 is the utility model shaft position sensor radially layout schematic diagram;
Fig. 5 is the utility model radial displacement transducer layout radial section schematic diagram;
Fig. 6 (a) is without tradition magnetic bearing air-gap field distribution map during radial displacement;
Fig. 6 (b) is without annular poles magnetic bearing air-gap field distribution map during radial displacement;
Fig. 7 (a) is tradition magnetic bearing air-gap field distribution map during generation radial displacement;
Fig. 7 (b) is annular poles magnetic bearing air-gap field comparison diagram during generation radial displacement;
Wherein, 1. stator core, 2. coil, 3. rotor core, 4. magnetic circuit magnetic flux, 5. rotor, magnetic pole 6., magnetic pole 7., 8. radial displacement transducer, 9. controller, 10. shaft position sensor, 11. power amplifiers, 12. grooves, 13. permanent-magnetic clamps.
Embodiment
Below in conjunction with drawings and Examples, embodiment of the present utility model is described in further detail.
A kind of annular poles structure, comprising: inner side magnetic pole 7 unshakable in one's determination and outside magnetic pole 6; Described inner side magnetic pole 7 is cylindric, and outside magnetic pole 6 is cylindric, and inner side magnetic pole 6 is arranged on the inside of outside magnetic pole 7; The end face of described inner side magnetic pole 6 and outside magnetic pole 7 has at least an end face to have at least one circle groove 12, and described groove 12 forms donut structure on magnetic pole face, interior outside.
This annular poles structure can be applied in traditional magnetic bearing structure, only need utilize mechanical processing technique at magnetic pole place, magnetic pole strength is processed into polycyclic structures, all the other structures and traditional magnetic bearing structure basically identical.The inner side magnetic pole 7 of stator core 1 is cylindric, and outside magnetic pole 6 is cylindric, and in interior outside, there is groove 12 structure at magnetic pole face place, makes magnetic pole strength form multiple donut shape; Rotor core 3 magnetic pole is relative with stator core 1, and surface groove structures is identical, be also multiple donut shapes, and the annular poles size of rotor core is identical with stator core.
By magnetic induction intensity and the Magnetic field distribution of annular poles structural change stator and rotor cores air-gap field, thus strengthen the radial forces between stator core 1 and rotor core 3.
This annular poles structure also can be applied to and of the present utility modelly realize in the axial magnetic bearing structure of rotor five-degree magnetic suspension by axial magnetic bearing, as Figure 1-3, a kind of axial magnetic bearing structure with annular poles, comprise magnetic suspension rotor 5 and arrange axial magnetic bearing for providing rotor axial suspending power and radial suspension force along the axial two ends of magnetic suspension rotor 5 respectively, the axial magnetic bearing at rotor axial two ends is symmetrically distributed; Stator core 1 is identical with rotor core 3 magnetic pole place structure, magnetic pole is divided into inner side magnetic pole 7 and outside magnetic pole 6, interior outside magnetic pole 7 forms polycyclic structures by machining, rotor core 3 is positioned opposite with the magnetic pole of stator core 1, field structure and inner side magnetic pole 7 all identical with the donut physical dimension of outside magnetic pole 6 end face, annular poles axial magnetic bearing stators and rotators end view drawing is respectively as shown in Figures 2 and 3.
Axis or radial direction arrange shaft position sensor 10 respectively, and shaft position sensor 10 is connected with controller 9, and controller 9 is connected respectively by the coil 2 of power amplifier 11 with magnetic suspension rotor axial two ends axial magnetic bearing.
Axial displacement signal for measuring the axial displacement of rotor in real time, and is input in controller by shaft position sensor 10.Shaft position sensor 10 can be positioned over rotor 5 axially, and two shaft position sensors 10 are placed in the axial two ends of rotor 5, measures rotor 5 axial displacement and after carrying out difference, input control device 9.Sensor can be eddy current displacement sensor, inductance displacement sensor, hall displacement transducer etc., but be not limited to above these.
It is radial that shaft position sensor 10 also can be positioned over rotor 5, as shown in Figure 4, rotor 5 to be arranged a permanent-magnetic clamp 13, permanent-magnetic clamp 13 adopts axial charging, permanent-magnetic clamp 13 position and sensor are in same axial position, and for the signal source of sensor, sensor is hall displacement transducer, rotor axial displacement signal is obtained, input control device 9 by detecting changes of magnetic field.
Radial displacement transducer 8 can be installed as required, selects driven suspension, then do not need installation position displacement sensor if radial; If radial direction needs ACTIVE CONTROL, then need, in radial direction, radial displacement transducer 8 is installed, as shown in Figure 5, radial displacement transducer 8 has four, is arranged in outside rotor, be divided into two groups, often organize two sensors and become 90 degree of at right angle settings, detect radial displacement, radial displacement transducer is connected with controller respectively, can be eddy current displacement sensor, inductance displacement sensor, hall displacement transducer etc., but be not limited to above these.
Controller 9 effect is the displacement signal according to input, by the control strategy preset, carries out computing, exports control signal.
Power amplifier 11 effect is that control signal is converted into electric current, is input in magnetic bearing, thus controls the suspension characteristic such as bearing capacity, rigidity, damping of magnetic bearing.
Coil 2 passes into electric current and produces magnetomotive force, in magnetic circuit, produce magnetic flux, and successively by stator core 1, inner side air gap, rotor core 3, outside air gap forms flux circuit, as indicated by the dashed arrow in fig. 1.Magnetic flux is by air gap between rotor, and set up air-gap field, at the magnetic force that rotor and air gap interface produce, magnetic force can be decomposed into axial force F z and radial force Fr.Changed magnetic induction intensity and the Magnetic field distribution of rotor air-gap field by the magnetic pole of ring structure, thus change axial force and the radial force of axial magnetic bearing.
When without radial displacement, the outside magnetic pole strength of magnetic bearing stator and rotor is just right, and between magnetic pole, magnetic axis is symmetrical, and radial force is zero.There is radial displacement between stator and rotor after, magnetic flux no longer axisymmetric distribution between magnetic pole, along with radial displacement increases, between magnetic pole, radial flux ratio increases, thus produces radial force.The direction of radial force is contrary with radial displacement direction.
Magnetic pole end face in the utility model between rotor is made up of multiple donut shape, when there is radial displacement, this arrangement reduces the ratio of axial magnetic flux between magnetic pole, add the ratio of radial flux between magnetic pole, thus the radial force between stator and rotor is increased, reduce because magnetic pole right opposite is long-pending simultaneously, axial force can be made to reduce.
In Fig. 1, outside magnetic pole 7 is 2 rings, and inner side magnetic pole 6 is 2 rings, but is not limited to 2, can be multiple ring.
For outside double-ring magnetic pole, the impact of annular poles on air-gap field and bearing capacity is described, interior outer ring, and multi-annular magnetic pole situation is similar.Fig. 6 (a) and Fig. 6 (b) is without tradition magnetic bearing and annular poles magnetic bearing air-gap field comparison diagram during radial displacement, outside magnetic pole 7 is made up of 2 annular poles, visible annular poles makes edge flux ratio increase in total magnetic flux in air-gap field between rotor, Fig. 7 (a) and Fig. 7 (b) is the air-gap field comparison diagram when there is radial displacement, tradition magnetic bearing due to magnetic pole right opposite long-pending larger, magnetic pole just to magnetic flux in region based on axial magnetic flux, axial magnetic flux ratio is high; And annular poles makes the long-pending reduction of magnetic pole right opposite, in air-gap flux, radial component increases, and magnetic flux radial component will make the radial force of axial magnetic bearing and radial rigidity strengthen.
By reference to the accompanying drawings embodiment of the present utility model is described although above-mentioned; but the restriction not to the utility model protection domain; one of ordinary skill in the art should be understood that; on the basis of the technical solution of the utility model, those skilled in the art do not need to pay various amendment or distortion that creative work can make still within protection domain of the present utility model.
Claims (8)
1. an annular poles structure, is characterized in that, comprising: inner side magnetic pole unshakable in one's determination and outside magnetic pole; Described inner side magnetic pole is cylindric, and outside magnetic pole is cylindric, and inner side magnetic pole is arranged on the inside of outside magnetic pole; The end face of described inner side magnetic pole and outside magnetic pole has at least an end face to have at least one circle groove, and described groove forms donut structure on magnetic pole face, interior outside.
2. a kind of annular poles structure as claimed in claim 1, it is characterized in that, described iron core is stator core, the field structure of the rotor core relative with described stator core magnetic pole is identical with described stator core field structure, and inner side magnetic pole is identical with the donut physical dimension of outside magnetic pole end face;
By magnetic induction intensity and the Magnetic field distribution of annular poles structural change stator and rotor cores air-gap field, thus strengthen the radial forces between stator core and rotor core.
3. one kind has the axial magnetic bearing of annular poles structure according to claim 1, it is characterized in that, comprise magnetic suspension rotor, axial two ends along described magnetic suspension rotor arrange the axial magnetic bearing for providing rotor axial suspending power and radial suspension force respectively, and the axial magnetic bearing at described rotor axial two ends is symmetrically distributed;
Described magnetic suspension rotor magnetic pole unshakable in one's determination and stator core is annular poles structure, and the magnetic pole of rotor core and stator core is positioned opposite, field structure and inner side magnetic pole all identical with the donut physical dimension of outside magnetic pole end face.
4. a kind of axial magnetic bearing with annular poles structure as claimed in claim 3, is characterized in that, by controlling the magnetic flux at air gap place between both sides axial magnetic bearing and rotor, produces axial restoring force, makes rotor axially keep stable suspersion initiatively;
When there is a certain radial displacement in rotor, electromagnetic force between axial magnetic bearing and rotor will produce radial component, and described radial component direction is contrary with rotor radial direction of displacement, point to axle center, described radial component makes rotor get back to radial equilibrium position, thus keeps the radial suspension of rotor;
When radially small angular variation occurs axle rotor, the radial component of described both sides axial magnetic bearing produces a restoring moment, makes rotor get back to equilibrium position.
5. a kind of axial magnetic bearing with annular poles structure as claimed in claim 3, it is characterized in that, at described rotor axial or radial direction, shaft position sensor is set respectively, described shaft position sensor is connected with controller, and described controller is connected respectively by the coil of power amplifier with magnetic suspension rotor axial two ends axial magnetic bearing.
6. a kind of axial magnetic bearing with annular poles structure as claimed in claim 5, it is characterized in that, when described shaft position sensor is arranged on rotor radial, rotor is arranged the permanent-magnetic clamp for providing sensor signal source, permanent-magnetic clamp adopts axial charging, and permanent-magnetic clamp position and sensor are in same axial position.
7. a kind of axial magnetic bearing with annular poles structure as claimed in claim 3, is characterized in that, if rotor radial selects driven suspension, then does not need to install radial displacement transducer;
If rotor radial needs ACTIVE CONTROL, then need at the radial displacement transducer of rotor radial installation for measuring rotor radial displacement, radial displacement transducer has four, be arranged in outside rotor, be divided into two groups, often organize two sensors and become 90 degree of at right angle settings, radial displacement is detected.
8. a kind of axial magnetic bearing with annular poles structure as claimed in claim 3, it is characterized in that, described axial magnetic bearing is electromagnetic bearing or electromagnet and permanent magnet hybrid magnetic bearing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520004699.9U CN204371940U (en) | 2015-01-05 | 2015-01-05 | A kind of annular poles structure and there is the axial magnetic bearing of annular poles structure |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520004699.9U CN204371940U (en) | 2015-01-05 | 2015-01-05 | A kind of annular poles structure and there is the axial magnetic bearing of annular poles structure |
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| CN204371940U true CN204371940U (en) | 2015-06-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201520004699.9U Expired - Fee Related CN204371940U (en) | 2015-01-05 | 2015-01-05 | A kind of annular poles structure and there is the axial magnetic bearing of annular poles structure |
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| CN (1) | CN204371940U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105281490A (en) * | 2015-11-30 | 2016-01-27 | 北京机械设备研究所 | Non-contact type active/passive hybrid control horizontal axial positioning device |
| CN104533947B (en) * | 2015-01-05 | 2017-08-18 | 山东大学 | A kind of annular poles structure and the axial magnetic bearing with annular poles structure |
| CN112968559A (en) * | 2021-02-20 | 2021-06-15 | 上海隐冠半导体技术有限公司 | Magnetic suspension rotating device |
-
2015
- 2015-01-05 CN CN201520004699.9U patent/CN204371940U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104533947B (en) * | 2015-01-05 | 2017-08-18 | 山东大学 | A kind of annular poles structure and the axial magnetic bearing with annular poles structure |
| CN105281490A (en) * | 2015-11-30 | 2016-01-27 | 北京机械设备研究所 | Non-contact type active/passive hybrid control horizontal axial positioning device |
| CN112968559A (en) * | 2021-02-20 | 2021-06-15 | 上海隐冠半导体技术有限公司 | Magnetic suspension rotating device |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150603 Termination date: 20160105 |