CN102632256A - Gas magnetic bearing electric spindle and control system thereof - Google Patents
Gas magnetic bearing electric spindle and control system thereof Download PDFInfo
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- CN102632256A CN102632256A CN2012101217524A CN201210121752A CN102632256A CN 102632256 A CN102632256 A CN 102632256A CN 2012101217524 A CN2012101217524 A CN 2012101217524A CN 201210121752 A CN201210121752 A CN 201210121752A CN 102632256 A CN102632256 A CN 102632256A
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
Abstract
The invention discloses a gas magnetic bearing electric spindle and a control system thereof. The gas magnetic bearing electric spindle structurally comprises a radial-axial auxiliary bearing, a radial displacement sensor, a radial displacement sensor bracket, a radial hybrid magnetic bearing, a limiting sleeve, a high-speed motor, a steel cylinder, an axial thrust gas bearing, a radial auxiliary bearing, a rotating shaft, a front end cover and a rear end cover. For the spindle with the novel structure, the invention provides a fuzzy control system of the gas magnetic bearing electric spindle based on a rough set theory method. The fuzzy control system comprises a controller, a power amplification module, a prototype body and a displacement detection module. Compared with a conventional fuzzy control system, the control system introduces a fuzzy control method of a rough set theory, simplifies original fuzzy control rules, and can effectively remove redundant information knowledge, so that the control system is more simple and easier to control, the dynamic performance of a spindle system is improved, and the performance of the control system can be effectively enhanced.
Description
Technical field
The invention belongs to mechanical manufacturing field and control technology field, be specifically related to a kind of gas magnetic bearing electricity main shaft and reach design of Fuzzy Control based on the Rough Set method to this main shaft.
Background technology
Along with science and technology development, ultraprecise processing has become one of key technology of in international competition, achieving success, and realizes that the most important condition of ultraprecise processing is the ultraprecise Digit Control Machine Tool.The central factor that influences the ultra-precision machine tool precision is the rotating accuracy of main shaft, and main shaft will reach high rotating accuracy, and stability of rotation, friction, key are the structure of used accurate main shaft and the Control System Design of main shaft.
The magnetic bearing of existing gas magnetic bearing main shaft all adopts active magnetic bearings, and (for example publication number CN 101217243; The Chinese patent of publication number CN 10127240); Than active magnetic bearings, the magnetic field that hybrid magnetic suspension bearing utilizes permanent magnet to produce has replaced the quiescent biasing magnetic field that electromagnet produced in the Active Magnetic Suspending Bearing; Power attenuation is reduced greatly; Reduce the number of ampere turns of electromagnet, dwindled the magnetic bearing volume, and improved the usefulness of magnetic bearing.
Controller design aspect in the control system, the PID controllers that adopt are controlled main shaft more on the engineering.But this method too relies on the model parameter of control object, and robustness is relatively poor, for gas magnetic bearing electricity main shaft this type complicacy and extremely accurate control, adopts the PID controller merely, is difficult to satisfy the requirement of the accurate control of system.And fuzzy control utilizes human expert's experience, has shown the advantage that robustness is good, control performance is high for control non-linear, complex object.But fuzzy control rule is the summary of experience according to the people to be obtained; Usually be not sufficiently complete and subjectivity strong; And when input, output number and linguistic variable divided rank increase; The fuzzy control rule number increases sharply, and brings difficulty to The Design of Fuzzy Logic Controller, also can influence the performance of fuzzy control.A large amount of empirical datas can effectively analyzed and handle to Rough Set, and therefrom find implicit knowledge, discloses potential rule, is specially adapted to Based Intelligent Control.
Summary of the invention
The objective of the invention is the deficiency that exists to prior art, provide a kind of reasonable in design, low in energy consumption, volume is little, in light weight, convenient processing and manufacture and can improve the ultraprecise spindle rotation accuracy, guarantee a kind of new gas magnetic bearing electricity main shaft of rigidity.And to the main shaft of this new structure; Design a kind of control system that has based on the gas magnetic bearing electricity main shaft fuzzy controller of Rough Set method, make the control system simpler, be easier to control; The dynamic property of axis system improves, and can effectively improve the performance of control system.
The technical scheme that realizes the object of the invention is:
A kind of gas magnetic bearing electricity main shaft; Comprise radial-axial auxiliary bearing, radial displacement transducer, radial displacement transducer support, radial hybrid magnetic bearing, spacing collar, high-speed electric expreess locomotive, steel cylinder, radial gas bearing provided, axial thrust gas bearing, radially auxiliary bearing, rotating shaft, drive end bearing bracket and rear end cap; Wherein, the radial-axial auxiliary bearing adopts angular contact ball bearing; Radially auxiliary bearing adopts cylinder roller bearing; Radial displacement transducer adopts current vortex sensor, is installed on the radial displacement transducer support; Radial hybrid magnetic bearing is four field structure magnetic bearings, and its biasing magnetic flux is produced by the permanent magnet of axial charging, and the control magnetic flux is produced by the control coil that is connected with DC current; High-speed electric expreess locomotive is built-in variable-frequency motor; Spacing collar is used for fixing in the main shaft each part in axial installation site.
To above-mentioned gas magnetic bearing electricity main shaft, the technical scheme that control of the present invention system adopts is:
A kind of control system of gas magnetic bearing electricity main shaft; Form by controller, power amplifier module, model machine body and displacement detecting module; Wherein, said controller comprises based on the PID controller under the fuzzy regular online adjustment of adjusting of Rough Set method, based on the 2nd PID controller and power and current transformation under the fuzzy regular online adjustment of adjusting of Rough Set method; Said power amplifier module comprises current track inverter; Said model machine body comprises radial hybrid magnetic bearing and rotating shaft front end; Said displacement detecting module comprises first displacement transducer, second displacement transducer and displacement interface circuit; The radial position of said rotating shaft front end is carried out differential detection through current vortex first displacement transducer, second displacement transducer, and detected displacement signal is handled through said displacement interface circuit, the output signal of displacement after the output modulation
x,
y, and with given reference position signal
x *,
y *Compare the deviation that obtains
e x ,
e y And rate of change
De x ,
De y Through handling, adjust parameter in real time based on PID controller under the fuzzy regular online adjustment of adjusting of Rough Set method and the 2nd PID controller under the fuzzy regular online adjustment of adjusting
K p,
K i,
K dSize, thereby obtain PID controller power output signal
F Xx With
F Yy , again through exertin and current transformation output three-phase current reference signal
i A *,
i B *,
i C *, handle than link through the chain rate that stagnates at last, by current track inverter output three-phase current
i A,
i B, i
CDrive the coil of said radial hybrid magnetic bearing.
In the present invention, described control system based on fuzzy control adopts the Fuzzy PID based on the Rough Set method.The method for simplifying of knowledge-representation system decision rule is simplified original fuzzy control rule in the applying rough set theory, obtains the rough set fuzzy control rule.In the fuzzy control, through the displacement of displacement interface circuit modulation output
x,
yWith reference position signal
x *,
y *Deviation
e x ,
e y And deviation
e x ,
e y Rate of change
De x ,
De y As the conditional attribute in the decision table, decision controller power output signal
F Xx ,
F Yy Size
K p,
K i,
K d(PID controller major parameter) is as decision attribute.Through the yojan decision table, obtain a plurality of different yojan, and all corresponding decision rule of each yojan obtains thus a series of
e x ,
e y ,
De x ,
De y With
K p,
K i,
K dCorresponding control law.Through every control law is set confidence level and threshold values, reject underproof rule and be provided with, thereby use minimum essential condition attribute just can obtain and the identical result of prime information table, remove redundancy knowledge effectively.If further improve the accuracy and the rapidity of control, can be according to calculating
e x ,
e y ,
De x ,
De y With the fuzzy nearness of different control laws, control thereby extract a certain rule, perhaps merge the control corresponding rule with corresponding method.
The present invention's advantage compared with prior art is:
1, traditional ultraprecise main shaft is supported separately by hydrostatic gas-lubricated bearing supporting or magnetic bearing, better effect when the present invention adopts hydrostatic gas-lubricated bearing and magnetic bearing combining form to reach to use separately than both.Hydrostatic gas-lubricated bearing can remedy the little deficiency of magnetic bearing bearing capacity, and magnetic bearing can remedy the uppity shortcoming of hydrostatic gas-lubricated bearing, and can realize higher rotating accuracy.
2, the magnetic bearing of traditional Ultraprecise electric spindle adopts the active magnetic bearings structure, and the present invention adopts the hybrid magnetic bearing structure, owing to cancelled bias current, has reduced the number of ampere turns of electromagnet, has reduced the power consumption of power amplifier, has reduced the cost of axis system.
3, be directed against definite problem of " the bottleneck "-fuzzy control rule of fuzzy theory, introduced Rough Set, propose the two is combined the design that is applied to gas magnetic bearing electricity spindle control system; Compare with the traditional fuzzy control method, the inventive method is on original fuzzy control rule basis, to carry out yojan, can remove redundancy knowledge effectively; Make the control system simpler; Be easier to control, the dynamic property of axis system improves, and can effectively improve the performance of control system.
Description of drawings
Fig. 1 is the structural representation of a kind of gas magnetic bearing electricity of the present invention main shaft.
Fig. 2 is the control system block diagram of the present invention's electricity main shaft.
The specific embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is further specified.
As shown in Figure 1; For main shaft of the present invention comprises radial-axial auxiliary bearing 1, radial displacement transducer 2, radial displacement transducer support 3, radial hybrid magnetic bearing 4, spacing collar 5, high-speed electric expreess locomotive 6, steel cylinder 7, radial gas bearing provided 8, axial thrust gas bearing 9, radially auxiliary bearing 10, rotating shaft 11, drive end bearing bracket 12 and rear end cap 13; Wherein, radial-axial auxiliary bearing 1 adopts angular contact ball bearing; Radially auxiliary bearing 10 adopts cylinder roller bearing; Radial displacement transducer 2 adopts current vortex sensor, is installed on the radial displacement transducer support 3; Radial hybrid magnetic bearing 4 is four field structure magnetic bearings, and its biasing magnetic flux is produced by the permanent magnet of axial charging, and the control magnetic flux is produced by the control coil that is connected with DC current; High-speed electric expreess locomotive 6 is built-in variable-frequency motor; Spacing collar 5 is used for fixing in the main shaft each part in axial installation site.
As shown in Figure 2; For the radially two degrees of freedom of rotating shaft 11 front ends that supported by radial hybrid magnetic bearing 4 to the present invention is carried out control system designed; By controller (comprising) based on the PID controller 14 under the fuzzy rule 16 online adjustment of adjusting of Rough Set method, based on PID controller 15, power/current transformation 18 under the fuzzy rule 17 online adjustment of adjusting of Rough Set method; Power amplifier module (current track inverter 19); Model machine body (comprising radial hybrid magnetic bearing 4, rotating shaft 11 front ends), displacement detecting module (comprising displacement transducer 20, displacement transducer 21, displacement interface circuit 22) is formed.Shown in the radial position of rotating shaft 11 front ends carry out differential detection through eddy current displacement sensor 20, displacement transducer 21, the output signal of displacement of detected displacement signal after through the 22 output modulation of displacement interface circuit
x,
y, with given reference position signal
x *,
y *Compare the deviation that obtains
e x ,
e y And rate of change
De x ,
De y The fuzzy rule 16 of adjusting through based on the Rough Set method is handled the adjustment parameter with the PID controller 14 under the fuzzy rule 17 online adjustment of adjusting with PID controller 15
K p,
K i,
K dThereby, obtain PID controller power output signal
F Xx With
F Yy , again through exertin and current transformation 18 output three-phase current reference signals
i A *,
i B *,
i C *, handle than link through the chain rate that stagnates at last, by current track inverter 19 output three-phase currents
i A,
i B, i
CDrive the coil of radial hybrid magnetic bearing 4.
Claims (2)
1. gas magnetic bearing electricity main shaft; Comprise radial-axial auxiliary bearing (1), radial displacement transducer (2), radial displacement transducer support (3), radial hybrid magnetic bearing (4), spacing collar (5), high-speed electric expreess locomotive (6), steel cylinder (7), radial gas bearing provided (8), axial thrust gas bearing (9), radially auxiliary bearing (10), rotating shaft (11), drive end bearing bracket (12) and rear end cap (13), it is characterized in that: radial-axial auxiliary bearing (1) adopts angular contact ball bearing; Radially auxiliary bearing (10) adopts cylinder roller bearing; Radial displacement transducer (2) adopts current vortex sensor, is installed on the radial displacement transducer support (3); Radial hybrid magnetic bearing (4) is four field structure magnetic bearings, and its biasing magnetic flux is produced by the permanent magnet of axial charging, and the control magnetic flux is produced by the control coil that is connected with DC current; High-speed electric expreess locomotive (6) is built-in variable-frequency motor; Spacing collar (5) is used for fixing in the main shaft each part in axial installation site.
2. control system of gas magnetic bearing electricity main shaft according to claim 1; Form by controller, power amplifier module, model machine body and displacement detecting module; It is characterized in that said controller comprises based on the PID controller (14) under the online adjustment of the fuzzy rule of adjusting (16) of Rough Set method, based on the 2nd PID controller (15) under the online adjustment of the fuzzy rule of adjusting (17) of Rough Set method and power and current transformation (18); Said power amplifier module comprises current track inverter (19); Said model machine body comprises radial hybrid magnetic bearing (4) and rotating shaft (11) front end; Said displacement detecting module comprises first displacement transducer (20), second displacement transducer (21) and displacement interface circuit (22); The radial position of said rotating shaft (11) front end is carried out differential detection through current vortex first displacement transducer (20), second displacement transducer (21); Detected displacement signal is handled through said displacement interface circuit (22), the output signal of displacement after the output modulation
x,
y, and with given reference position signal
x *,
y *Compare the deviation that obtains
e x ,
e y And rate of change
De x ,
De y Through handling, adjust parameter in real time based on the 2nd PID controller (15) under PID controller (14) under the online adjustment of the fuzzy rule of adjusting (16) of Rough Set method and the fuzzy online adjustment of rule (17) of adjusting
K p,
K i,
K dSize, thereby obtain PID controller power output signal
F Xx With
F Yy , again through exertin and current transformation (18) output three-phase current reference signal
i A *,
i B *,
i C *, handle than link through the chain rate that stagnates at last, by current track inverter (19) output three-phase current
i A,
i B, i
CDrive the coil of said radial hybrid magnetic bearing (4).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210121752.4A CN102632256B (en) | 2012-04-24 | 2012-04-24 | Gas magnetic bearing electric spindle and control system thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210121752.4A CN102632256B (en) | 2012-04-24 | 2012-04-24 | Gas magnetic bearing electric spindle and control system thereof |
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| Publication Number | Publication Date |
|---|---|
| CN102632256A true CN102632256A (en) | 2012-08-15 |
| CN102632256B CN102632256B (en) | 2014-05-14 |
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| CN201210121752.4A Expired - Fee Related CN102632256B (en) | 2012-04-24 | 2012-04-24 | Gas magnetic bearing electric spindle and control system thereof |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103034126A (en) * | 2012-12-24 | 2013-04-10 | 江苏大学 | Controlling system and controlling method of axial off-center magnetic bearing of outer rotor of constant current source |
| CN104439301A (en) * | 2014-12-02 | 2015-03-25 | 华侨大学 | Rotary ultrasonic spindle supported by magnetic-suspension bearing |
| CN105259785A (en) * | 2015-10-28 | 2016-01-20 | 江苏大学 | Three-degree-of-freedom hybrid magnetic bearing variable saturation flexible variable structure control method |
| CN106825627A (en) * | 2017-02-15 | 2017-06-13 | 江苏大学 | A kind of inverter driving ejector half five degree of freedom hybrid magnetic bearing supports electro spindle |
| CN109236860A (en) * | 2018-11-30 | 2019-01-18 | 广西恒达电机科技有限公司 | A kind of combination bearing for rotary machine rotor |
| CN109723719A (en) * | 2019-03-04 | 2019-05-07 | 青岛大学 | A kind of differential detection formula Self-sensing Electromagnetic bearing and its implementation |
| CN110756830A (en) * | 2019-11-15 | 2020-02-07 | 重庆工商大学 | Intelligent high-speed motorized spindle integrating multi-parameter detection |
| CN113369507A (en) * | 2021-06-28 | 2021-09-10 | 重庆工商大学 | High-speed high-precision electric spindle integrating three-dimensional vibration active control function |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106019945B (en) * | 2016-07-14 | 2019-03-05 | 江苏大学 | A kind of building method of flying wheel battery axial magnetic bearing anti-interference controller |
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2012
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Patent Citations (5)
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|---|---|---|---|---|
| JPH1113760A (en) * | 1997-04-28 | 1999-01-22 | Ntn Corp | Hydrostatic magnetic composite bearing |
| CN101229590A (en) * | 2008-02-25 | 2008-07-30 | 哈尔滨工业大学 | Ultra-sophisticated aerostatic motorized spindle system |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103034126A (en) * | 2012-12-24 | 2013-04-10 | 江苏大学 | Controlling system and controlling method of axial off-center magnetic bearing of outer rotor of constant current source |
| CN104439301A (en) * | 2014-12-02 | 2015-03-25 | 华侨大学 | Rotary ultrasonic spindle supported by magnetic-suspension bearing |
| CN105259785A (en) * | 2015-10-28 | 2016-01-20 | 江苏大学 | Three-degree-of-freedom hybrid magnetic bearing variable saturation flexible variable structure control method |
| CN106825627A (en) * | 2017-02-15 | 2017-06-13 | 江苏大学 | A kind of inverter driving ejector half five degree of freedom hybrid magnetic bearing supports electro spindle |
| CN109236860A (en) * | 2018-11-30 | 2019-01-18 | 广西恒达电机科技有限公司 | A kind of combination bearing for rotary machine rotor |
| CN109236860B (en) * | 2018-11-30 | 2024-04-16 | 广西恒达电机科技有限公司 | Combined bearing for rotary machinery rotor |
| CN109723719A (en) * | 2019-03-04 | 2019-05-07 | 青岛大学 | A kind of differential detection formula Self-sensing Electromagnetic bearing and its implementation |
| CN110756830A (en) * | 2019-11-15 | 2020-02-07 | 重庆工商大学 | Intelligent high-speed motorized spindle integrating multi-parameter detection |
| CN113369507A (en) * | 2021-06-28 | 2021-09-10 | 重庆工商大学 | High-speed high-precision electric spindle integrating three-dimensional vibration active control function |
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| CN102632256B (en) | 2014-05-14 |
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Granted publication date: 20140514 Termination date: 20200424 |