CN1851389A - Magnetic suspension bearing differential transformer type displacement sensor - Google Patents
Magnetic suspension bearing differential transformer type displacement sensor Download PDFInfo
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- CN1851389A CN1851389A CN 200610038570 CN200610038570A CN1851389A CN 1851389 A CN1851389 A CN 1851389A CN 200610038570 CN200610038570 CN 200610038570 CN 200610038570 A CN200610038570 A CN 200610038570A CN 1851389 A CN1851389 A CN 1851389A
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- 238000006073 displacement reaction Methods 0.000 title claims abstract description 27
- 239000000725 suspension Substances 0.000 title claims abstract description 22
- 230000003321 amplification Effects 0.000 claims abstract description 15
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 15
- 230000004907 flux Effects 0.000 claims abstract description 5
- 238000012360 testing method Methods 0.000 claims description 12
- 230000000295 complement effect Effects 0.000 claims description 6
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 claims description 5
- 238000001914 filtration Methods 0.000 claims description 3
- 238000003475 lamination Methods 0.000 claims description 3
- 238000005086 pumping Methods 0.000 claims description 3
- 229910001369 Brass Inorganic materials 0.000 claims description 2
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 claims description 2
- 239000010951 brass Substances 0.000 claims description 2
- 230000004075 alteration Effects 0.000 abstract 3
- 230000004048 modification Effects 0.000 abstract 1
- 238000012986 modification Methods 0.000 abstract 1
- 239000003990 capacitor Substances 0.000 description 7
- 238000000926 separation method Methods 0.000 description 4
- 238000010276 construction Methods 0.000 description 3
- 238000005339 levitation Methods 0.000 description 3
- 238000003754 machining Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
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- 238000005520 cutting process Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
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- 239000000203 mixture Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
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- 230000011664 signaling Effects 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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Abstract
The invention discloses a magnetic suspension bearing differential transformer displacement sensor that includes differential transformer and detecting circuit. The detecting circuit includes sine wave generating circuit, current amplification circuit, detecting circuit, and low passing filter circuit. The sine wave would be amplified and generate the magnetic flux of the primary coil of the transformer. The alteration of the displacement of the rotator would cause the alteration of mutual inductance between primary coil and secondary primary to generate the corresponding alteration of the secondary coil induced voltage that could form the DC voltage signal of the rotator. The invention has bright application prospect in magnetic suspension bearing. It could also be used to measure other type linear movement or anger movement after taking a little modification.
Description
One, technical field
The invention belongs to a kind of displacement transducer, particularly be applied to magnetic suspension bearing displacement transducer radially.
Two, background technology
Magnetic suspension bearing is to utilize magneticaction that rotor is suspended in the space, makes a kind of novel high-performance bearing of realizing not having machinery friction supporting between rotor and the stator.Compare with sliding bearing with traditional rolling bearing, the tangible characteristics of magnetic suspension bearing are there is not Mechanical Contact, and its supporting power is controlled, do not have mechanical friction and wearing and tearing, thereby reduced work energy consumption and noise, prolonged serviceable life, power waste is little, is fit to be applied in the occasion that runs up; Since saved lubricated and sealing system, therefore pollution-free, can be applicable to particular job environment such as vacuum ultra-clean and extreme temperature and pressure.Displacement transducer is the important component part of magnetic levitation bearing system, and the quality of its performance influences the performance of total system to a great extent.
Magnetic suspension bearing has the requirement of displacement transducer: can realize non-cpntact measurement; The change in displacement that can truly reflect rotor center; Have very high sensitivity, signal to noise ratio (S/N ratio), the linearity, temperature stability, antijamming capability and reach accurate repeatability by force, also require to have certain frequency response range simultaneously.At present, what generally use in magnetic levitation bearing system is current vortex sensor, but find many inconveniences in the process of using current vortex sensor: the magnetic levitation bearing system to a five degree of freedom then needs 10 sensors, number of sensors is many, not only increase the cost of total system, and increased unreliable factor; Electric vortex sensor measuring be the situation that rotor surface moves, can only reflect the position of rotor center indirectly, when rotor rotation, reflection be the situation of rotor eddy; Current vortex sensor is to be fixed on the sensor stand by thread connection, assembly process cumbersome and when shaking in system or other reason can make sensor loosening; For some particular application, as dustproof, isolate etc., in the time of need adding the layer of metal diaphragm between magnetic suspension rotor and magnetic suspension bearing stator, current vortex sensor can't be competent at.
Inductance type transducer is a kind of device that utilizes the variation realization non-electricity measure of self-induction of loop or mutual inductance.The present invention is a kind of of inductance type transducer, be to utilize coil mutual inductance principle to make, it can be the physical quantity of input such as displacement, vibration, pressure and other parameters, be converted to the variation of the coefficient of mutual inductance M of coil, and the variation of M converts the variation of voltage or electric current in circuit, promptly realizes the conversion of non electrical quantity to electric weight.
Three, summary of the invention
1, goal of the invention: the object of the present invention is to provide a kind of simple in structure, cost is low, reliability is high and can satisfy the displacement transducer of magnetic suspension bearing requirement.
2, technical scheme: purpose of the present invention can reach by following scheme:
A kind of magnetic suspension bearing differential transformer type displacement sensor, it is characterized in that: it comprises differential transformer and testing circuit, wherein testing circuit comprises sine wave generating circuit, current amplification circuit, detecting circuit and low-pass filter circuit, the sine wave that sine wave generating circuit produces amplifies the primary coil of exporting to transformer through current amplification circuit and produces exciting flux, the variation of the displacement of magnetic suspension bearing rotor causes the variation of mutual inductance between transformer and the secondary coil, cause the corresponding change of the coil-induced voltage of transformer secondary output, the coil-induced voltage of transformer secondary output draws the d. c. voltage signal that becomes corresponding relation with the rotor displacement size and Orientation behind detecting circuit and low-pass filter circuit.
Differential transformer: convert this non-electric charge quantity signalling of displacement of magnetic suspension bearing rotor to become to determine relation with rotor displacement electric weight.Consider characteristics and magnetic structure on the magnetic bearing structure, the profile of differential transformer is a circular configuration, and the differential transformer iron core adopts ∏ type two toothings.This structure not only is convenient to install, dismounting, also is convenient to machining.
Testing circuit: testing circuit of the present invention is a differential rectification metering circuit that designs voluntarily.This circuit mainly is made up of four parts: sine wave generating circuit, current amplification circuit, detecting circuit and low-pass filter circuit.Sine wave generating circuit and current amplification circuit provide pumping signal for the primary coil of differential transformer, and detecting circuit and the voltage signal that low-pass filter circuit induces the differential transformer secondary coil carry out the d. c. voltage signal that full-wave rectification and filtering obtain becoming with the displacement size and Orientation corresponding relation.
3, beneficial effect: good effect of the present invention is: the present invention is based on transformer principle, when little gap, it is big, highly sensitive that the present invention has an inductance value, and the signal to noise ratio (S/N ratio) height is not subject to the interference of extraneous stray magnetic field.Differential transformer physical construction can whole be processed, by improving machining accuracy and assembly precision, the axis of each magnetic pole that can guarantee differential transformer is concentric with the axis of magnetic suspension bearing, has reduced center sensor and has not overlapped the influence that brings to system's control accuracy with the magnetic suspension bearing center.The magnetic core of the sensor on two degree of freedom of magnetic suspension bearing is made in one on the whole, is convenient to install, also reduced processing cost simultaneously.Dustproof, the isolation aspect, as long as separation layer is non-magnetic metal material, because the exciting flux that transformer produces can be passed through separation layer and the gap arrives rotor, get back to transformer core composition flux circuit through gap and separation layer again, so performance of the present invention can not be subjected to the influence of separation layer.Testing circuit sine wave generating circuit of the present invention adopts special signal generation chip, and circuit is simple, waveform frequency and amplitude stability; Current amplification circuit dependable performance, waveform do not distort with the load change; Detecting circuit is full-wave rectification, has improved the sensitivity of sensor; Low-pass filter circuit is the active low pass Butterworth filter of second order, and its low side amplitude versus frequency characte is very near ideal situation.
Four, description of drawings
Fig. 1 is a mechanical construction drawing of the present invention;
Fig. 2 is coil connecting line figure of the present invention;
Fig. 3 is a testing circuit sine wave signal generation circuit diagram of the present invention;
Fig. 4 is testing circuit current amplification circuit figure of the present invention.
Fig. 5 is testing circuit detecting circuit figure of the present invention;
Fig. 6 is testing circuit low-pass filter circuit figure of the present invention.
Five, embodiment
As shown in Figure 1, the physical construction of differential transformer of the present invention is made up of clamping plate 1 and magnetic core 2.Magnetic core 2 is to be that the iron-nickel alloy 1J79 circular laminations of 0.05mm is formed by stacking by thickness, and the 1J79 lamination stack of some is incorporated into certain thickness, compresses; Clamping plate 1 with brass material are clipped in the magnetic core two ends then, and with rivet two clamping plate and magnetic core are fixed; Carry out the line cutting then, cut out cylindrical and magnetic pole; To sever the shape that becomes magnetic core among Fig. 1 between per two teeth of magnetic core again; Last cylindrical grinding and pole bore.With the coil rack of teflon or plastic processing transformer, and with line directly be 0.23mm QZ type high strength enamelled wire two-wire and around, around 50 circles.After coil winds, before assembling, must guarantee that each coil is available, promptly guarantee to insulate between each coil conducting (disconnecting) and the lead, measure the parameter (resistance value, inductance value) of each coil simultaneously with the RCL instrument, the coil that parameter value is close mates in pairs, will prepare right coil again and be assemblied on each magnetic pole of ready-made transformer.Coil connecting line on each magnetic pole as shown in Figure 2.Fig. 2 has only given the line of coil on the one degree of freedom, and the line on another degree of freedom is identical with it.After each coil connecting line connects, it is drawn, one degree of freedom has 5 joints, two is the driving source input adapter of primary coil, other 3 is the secondary coil out splice going splice of transformer, and one of them is earth connection point, and two other is the Signal connector of last lower core secondary coil.
The sine wave generating circuit of testing circuit of the present invention as shown in Figure 3.The pumping signal of the primary coil of transformer of the present invention is a sinusoidal signal, and it is to be produced by the special signal generation chip MAX038 of Maxim company, and it is the sinusoidal signal of 0.1Hz to 20MHz that MAX038 can produce frequency.Change capacitor C
2Appearance value and resistance R
1Resistance value can be used for setting the different base frequencies of MAX038, regulator potentiometer W
1The output signal frequency that can make MAX038 is in 0.3～1.7 times of adjusting of base frequency, capacitor C
1, capacitor C
3, capacitor C
4And capacitor C
5For filter capacitor is used for high frequency ripple on the filter out power line.The sinusoidal signal amplitude of MAX038 output is fixed on ± 1V.Disturb for the beat of eliminating between the two-freedom of the present invention, the primary coil of transformer is selected same driving source for use on each degree of freedom, for improving the driving force of driving source, must carry out electric current to driving source and amplify.Current amplification circuit as shown in Figure 4, it by a ratio circuit (by resistance R
1, resistance R
2, operational amplifier U
1, potentiometer W
1Form) and complementary symmetry circuit (by resistance R
4, resistance R
5, diode D
1, diode D
2, triode Q
1, triode Q
2Form) form.The sinusoidal signal of MAX038 output is through resistance R
1Arrive operational amplifier U
1, by regulator potentiometer W
1, make the amplitude of signal reach desired scope through the one-level in-phase amplification circuit, the signal after the amplification is through R
3Be sent to complementary symmetry circuit.Triode Q
1And Q
2Be respectively NPN type pipe and positive-negative-positive pipe, form the complementary output level, when static, at diode D
1, D
2The pressure drop of last generation is Q
1, Q
2A suitable bias voltage is provided, has made it to be in the lightly conducting state.Because circuit symmetrical flows through Q when static
1Collector current equal to flow through Q
2Collector current, be zero so flow through the electric current of load, be output as zero.When signal is arranged, because complementary symmetry circuit is operated in class AB, can carry out linear amplification to signal, and the driving force of signal can be provided greatly by this circuit, the primary coil of transformer is directly given in its output, and output signal does not distort with the change of load.Signal behind complementary symmetry circuit is added in load R
LOn, (be that output signal is the U among Fig. 2 for the primary coil of transformer in the present invention
In).Detecting circuit is made up of a multi-channel gating device and a differential circuit as shown in Figure 5.Sinusoidal signal after electric current amplifies is sent to the primary coil of transformer, and the transformer secondary output induction coil is VA, VB, and the line of they and multi-channel gating device is as shown in Figure 5.Among the figure synchronizing signal be one with secondary coil export synchronous square wave, it is provided by signal generation chip MAX038.It or be high level or for low level, the different pin (X of its residing different conditions multi-channel gating device
0, X
1, Y
0, Y
1) conducting and close, output pin X, Y are signal VA, the signal after the VB upper half exchange.Two output signals of multi-channel gating device are given a differential circuit, with behind two signal subtractions amplitude is proportional with rotor displacement, positive and negative and rotor displacement direction has certain relation, frequency is the signal of excitation frequency twice.Realized signal VA through this circuit, the full-wave rectification of the difference of VB.Low-pass filter circuit as shown in Figure 6, this low-pass filter is the unlimited gain multichannel feedback circuit in the Butterworth LPF, the signal behind rectification circuit (is the U among Fig. 6
i) send into filtering circuit, resistance R among the figure
2, R
3, capacitor C
1, C
2Be used for setting wave filter by frequency, resistance R
1Play metering function.Wave filter among the present invention filters out the high-frequency signal more than the 12kHz, the output signal U of wave filter
0Be the direct current signal consistent with the displacement size and Orientation.
Claims (4)
1, a kind of magnetic suspension bearing differential transformer type displacement sensor, it is characterized in that: it comprises differential transformer and testing circuit, wherein testing circuit comprises sine wave generating circuit, current amplification circuit, detecting circuit and low-pass filter circuit, the sine wave that sine wave generating circuit produces amplifies the primary coil of exporting to transformer through current amplification circuit and produces exciting flux, the variation of the displacement of magnetic suspension bearing rotor causes the variation of mutual inductance between transformer and the secondary coil, cause the corresponding change of the coil-induced voltage of transformer secondary output, the coil-induced voltage of transformer secondary output draws the d. c. voltage signal that becomes corresponding relation with the rotor displacement size and Orientation behind detecting circuit and low-pass filter circuit.
2, magnetic suspension bearing differential transformer type displacement sensor according to claim 1 is characterized in that: differential transformer adopts the iron-nickel alloy lamination stack to merge and forms with the brass cramping, and profile is a circular configuration, and magnetic core is ∏ type two toothings.
3, magnetic suspension bearing differential transformer type displacement sensor according to claim 1, it is characterized in that: sine wave generating circuit and current amplification circuit, comprise by special signal generation chip MAX038 output ± 1V sine voltage signal primary coil to transformer behind the current amplification circuit that amplifying circuit and complementary symmetrical expression circuit are formed provides a pumping signal.
4, magnetic suspension bearing differential transformer type displacement sensor according to claim 1, it is characterized in that, detecting circuit and low-pass filter circuit, comprise from the coil-induced voltage signal that comes out of transformer secondary output through an analog switch chip up and down two signals of upper half exchange back output of two signals of secondary coil to difference channel, two signal subtractions make the secondary coil output signal carry out full-wave rectification, and the voltage signal filtering more than the 12KHZ obtains becoming with displacement the d. c. voltage signal of corresponding relation in the signal after low-pass filter circuit is with rectification again.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610038570 CN1851389A (en) | 2006-03-02 | 2006-03-02 | Magnetic suspension bearing differential transformer type displacement sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610038570 CN1851389A (en) | 2006-03-02 | 2006-03-02 | Magnetic suspension bearing differential transformer type displacement sensor |
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| Publication Number | Publication Date |
|---|---|
| CN1851389A true CN1851389A (en) | 2006-10-25 |
Family
ID=37132877
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200610038570 Pending CN1851389A (en) | 2006-03-02 | 2006-03-02 | Magnetic suspension bearing differential transformer type displacement sensor |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100430168C (en) * | 2006-11-24 | 2008-11-05 | 南京航空航天大学 | Process for producing axial magnetic bearing structure |
| CN100451554C (en) * | 2007-01-17 | 2009-01-14 | 北京航空航天大学 | Device for discriminating rotar position of magnet suspension flywheel |
| CN105841598A (en) * | 2016-05-25 | 2016-08-10 | 北京泓慧国际能源技术发展有限公司 | Magnetic bearing displacement measurement method based on integration of actuator and sensor |
| CN107014405A (en) * | 2017-03-08 | 2017-08-04 | 北京航空航天大学 | A kind of self difference inductive displacement transducer for magnetic levitation bearing system |
| CN107014406A (en) * | 2017-03-16 | 2017-08-04 | 北京航空航天大学 | A kind of autodyne fraction eddy current displacement sensor for magnetic levitation bearing system |
| CN109341625A (en) * | 2018-11-23 | 2019-02-15 | 成都云材智慧数据科技有限公司 | A kind of negative electrode material coating thickness detection system |
| CN109489532A (en) * | 2018-10-29 | 2019-03-19 | 安徽理工大学 | A kind of magnetcisuspension ring ruler roadway deformation monitoring warning device |
| CN111623700A (en) * | 2020-07-31 | 2020-09-04 | 山东天瑞重工有限公司 | Magnetic suspension bearing inductance type displacement sensor |
| CN113251910A (en) * | 2021-07-06 | 2021-08-13 | 中国人民解放军海军工程大学 | Displacement detection method for weak coupling of detection coil and magnetic bearing |
| CN113513969A (en) * | 2021-06-04 | 2021-10-19 | 南京航空航天大学 | Self-inductance type inductance displacement sensor excitation circuit |
| CN114046753A (en) * | 2021-11-26 | 2022-02-15 | 广东美的暖通设备有限公司 | Magnetic suspension compressor, detection device for bearing rotor of magnetic suspension compressor and air conditioner |
| CN114216389A (en) * | 2022-02-08 | 2022-03-22 | 北京航空航天大学 | Testing and analyzing device for LVDT displacement sensor |
| CN114427824A (en) * | 2021-12-16 | 2022-05-03 | 洛阳轴承研究所有限公司 | Method for measuring axial displacement of magnetic bearing rotor |
| CN115622335A (en) * | 2022-12-20 | 2023-01-17 | 苏州苏磁智能科技有限公司 | Magnetic suspension motor and position detection sensor, detection circuit and bridge circuit thereof |
-
2006
- 2006-03-02 CN CN 200610038570 patent/CN1851389A/en active Pending
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100430168C (en) * | 2006-11-24 | 2008-11-05 | 南京航空航天大学 | Process for producing axial magnetic bearing structure |
| CN100451554C (en) * | 2007-01-17 | 2009-01-14 | 北京航空航天大学 | Device for discriminating rotar position of magnet suspension flywheel |
| CN105841598A (en) * | 2016-05-25 | 2016-08-10 | 北京泓慧国际能源技术发展有限公司 | Magnetic bearing displacement measurement method based on integration of actuator and sensor |
| CN107014405A (en) * | 2017-03-08 | 2017-08-04 | 北京航空航天大学 | A kind of self difference inductive displacement transducer for magnetic levitation bearing system |
| CN107014406A (en) * | 2017-03-16 | 2017-08-04 | 北京航空航天大学 | A kind of autodyne fraction eddy current displacement sensor for magnetic levitation bearing system |
| CN107014406B (en) * | 2017-03-16 | 2020-06-12 | 北京航空航天大学 | Self-differential eddy current displacement sensor for magnetic suspension bearing system |
| CN109489532A (en) * | 2018-10-29 | 2019-03-19 | 安徽理工大学 | A kind of magnetcisuspension ring ruler roadway deformation monitoring warning device |
| CN109341625A (en) * | 2018-11-23 | 2019-02-15 | 成都云材智慧数据科技有限公司 | A kind of negative electrode material coating thickness detection system |
| CN111623700A (en) * | 2020-07-31 | 2020-09-04 | 山东天瑞重工有限公司 | Magnetic suspension bearing inductance type displacement sensor |
| CN113513969A (en) * | 2021-06-04 | 2021-10-19 | 南京航空航天大学 | Self-inductance type inductance displacement sensor excitation circuit |
| CN113251910A (en) * | 2021-07-06 | 2021-08-13 | 中国人民解放军海军工程大学 | Displacement detection method for weak coupling of detection coil and magnetic bearing |
| CN113251910B (en) * | 2021-07-06 | 2021-11-19 | 中国人民解放军海军工程大学 | Displacement detection method for weak coupling of detection coil and magnetic bearing |
| CN114046753A (en) * | 2021-11-26 | 2022-02-15 | 广东美的暖通设备有限公司 | Magnetic suspension compressor, detection device for bearing rotor of magnetic suspension compressor and air conditioner |
| CN114046753B (en) * | 2021-11-26 | 2024-04-26 | 广东美的暖通设备有限公司 | Magnetic suspension compressor, detection device of bearing rotor of magnetic suspension compressor and air conditioner |
| CN114427824A (en) * | 2021-12-16 | 2022-05-03 | 洛阳轴承研究所有限公司 | Method for measuring axial displacement of magnetic bearing rotor |
| CN114216389A (en) * | 2022-02-08 | 2022-03-22 | 北京航空航天大学 | Testing and analyzing device for LVDT displacement sensor |
| CN115622335A (en) * | 2022-12-20 | 2023-01-17 | 苏州苏磁智能科技有限公司 | Magnetic suspension motor and position detection sensor, detection circuit and bridge circuit thereof |
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