CN108051165A - The electromagnetic vibration generator system of actively positive rigidity resilient support is realized based on absolute position feedback - Google Patents
The electromagnetic vibration generator system of actively positive rigidity resilient support is realized based on absolute position feedback Download PDFInfo
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- CN108051165A CN108051165A CN201711020274.7A CN201711020274A CN108051165A CN 108051165 A CN108051165 A CN 108051165A CN 201711020274 A CN201711020274 A CN 201711020274A CN 108051165 A CN108051165 A CN 108051165A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M7/00—Vibration-testing of structures; Shock-testing of structures
- G01M7/02—Vibration-testing by means of a shake table
- G01M7/022—Vibration control arrangements, e.g. for generating random vibrations
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H9/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M7/00—Vibration-testing of structures; Shock-testing of structures
- G01M7/02—Vibration-testing by means of a shake table
- G01M7/025—Measuring arrangements
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Abstract
The electromagnetic vibration generator system for realizing actively positive rigidity resilient support based on absolute position feedback belongs to vibration measurement technical field；It is proposed a kind of positive rigidity resilient support method of active, using absolute type linear grating ruler as feedback displacement sensor, the relative displacement with actual zero point position is exported into the Lorentz force of constant ratio, so that electromagnetic vibration generator system moving-coil resilient support with linear rigidity in big stroke motion；Electromagnetic vibration generator system moving-coil series multistage power resistor increases load impedance, makes power amplifier when exporting milliampere grade ultralow frequency electric current with higher signal-to-noise ratio；The present invention can take into account big stroke, linear elasticity support, high s/n ratio, and a kind of big stroke high-performance electromagnetic vibration generator system control technology scheme is provided for superlow frequency vibrating calibration.
Description
Technical field
The invention belongs to vibration measurement technical fields, relate generally to a kind of based on the positive rigidity of absolute position feedback realization active
The electromagnetic vibration generator system of resilient support.
Background technology
The electromagnetic vibration generator system for generating standard vibration signal is that the key equipment of progress high-precision vibration calibration and country shake
The important component of dynamic measurement technology system.In recent years, aerospace, build a bridge, the fields such as protection against and mitigation of earthquake disasters propose
The demand of low frequency/superlow frequency vibrating calibration.To improve the signal-to-noise ratio of standard vibration signal, ensure the school of low frequency/superlow frequency vibrating
Quasi- precision, it is desirable that electromagnetic vibration generator system has stroke as big as possible, such as electromagnetic vibration generator system on the premise of thrust and precision is ensured
Output displacement peak-to-peak value is up to 1 meter or more, but will certainly increase non-linear factor (such as resilient support linear Stiffness, electromagnetism resistance
Air gap is uneven etc. when the non-linear of Buddhist nun's power, moving-coil move in magnetic field), so as to increase the total harmonic distortion of excitation waveform,
Calibration uncertainty is made to become larger.In addition, ultralow frequency large-stroke electromagnetic vibration moving-coil resistance value is in 1 ohms, when it is operated in
During ultralow frequency range, moving-coil input current peak value only has several to tens milliamperes, and power amplifier input voltage is in millivolt magnitude, power
Amplifier current output (signal-to-noise ratio, bias current etc.) influences the total harmonic distortion of waveform.
Tradition machinery resilient supporting unit (such as leaf spring, emulsion tube) provides reciprocating force and damping for the movement of electromagnetic vibration generator system
Power, there are serious nonlinear characteristic under the conditions of large deformation, the Acceleration pulse serious distortion that electromagnetic vibration generator system is caused to export.When
When electromagnetic vibration generator system is without mechanical elasticity support device, system is unstable, vibration signal equilbrium position, that is, dead-center position
It is variation, can not ensures the accuracy of dead-center position.Therefore, ultralow frequency large-stroke electromagnetic vibration must be by suitable anti-
Feedback control technology stablizes system.
What news of Zhejiang University etc. proposes a kind of electromagnetic vibration generator system control technology scheme, and (1. Zhejiang University " have based on straight
The shaking table system of line grating ruler feed back control system ", China Patent No.：ZL201110115702.7；2. Zhejiang University, " tool
Have the electromagnetic vibration platform system of adjustable electric Viscoelastic brace device ", China Patent No.：ZL201110113959.2；).The skill
In art scheme, using linear grating ruler as position sensor, adjustable amplifier, differentiator, adder, Adjustable Phase Shift are introduced
Device, subtracter, proportional controller form position feedback and velocity feedback, directly adjust support stiffness and the damping of moving component
Parameter realizes the support of big displacement linear elasticity, has many advantages, such as Parameter adjustable.Following problem makes existing for the technical solution
System adjustment is complicated：1) position sensor be incremental linear encoder, it is necessary to install null pick-up, and can not be true after powering off
Current location is recognized, it is necessary to which back to zero position remeasures after resetting；With accumulated error, when long distance measuring need it is accurate correct it is each
The error of pitch is to reduce accumulated error；2) there are differentiator, adjustable phase shifter, multiple adjustable amplifiers for feedback control system
Deng adjusting complexity；3) electromagnetic vibration generator system moving-coil resistance value is typically small, in 1 ohms, when shake table is operated in ultralow frequency range
When, the current peak loaded on moving-coil only has several mA, and corresponding signal generator input signal is very small, driving moving-coil electric current letter
It makes an uproar poor.
To sum up, due to factors such as resilient support linear Stiffness, power amplifier output current poor signal to noise, big row is caused
Waveform distortion is larger when journey electromagnetic vibration generator system is operated in ultralow frequency range, it is difficult to meet superlow frequency vibrating high-precision calibration.Therefore,
It proposes with linear elasticity support, high s/n ratio, the electromagnetic vibration generator system control technology scheme of extremely low waveform distortion, for vibration
The development of measurement technology is of great significance.
The content of the invention
The purpose of the present invention is be directed to existing large-stroke electromagnetic vibration control program there are the problem of, one kind is provided and is based on
Absolute position feedback realizes the electromagnetic vibration generator system of actively positive rigidity resilient support, and absolute position is realized using absolute linear grating ruler
Feedback generates with displacement into the reciprocal Lorentz force of constant ratio, actively realizes positive stiffness characteristics；Moving-coil Series power resistance,
Increase load impedance, power amplifier is made, with higher signal-to-noise ratio, can effectively to be solved when exporting milliampere grade ultralow frequency electric current
Problems and shortcomings existing for prior art provide a kind of high-precision, the ultralow frequency of big stroke electricity for superlow frequency vibrating calibration
Magnetic vibration platform control program.
The present invention technical solution be：
A kind of electromagnetic vibration generator system that actively positive rigidity resilient support is realized based on absolute position feedback, by signal generator,
Power amplifier, actively electromagnetic vibration generator system, positive rigidity resilient supporting unit and multiple power levels resistance composition, the positive rigidity of active
Resilient supporting unit includes absolute type linear grating ruler, serial encoder, controller, digital analog converter and subtracter；It is described
Absolute type linear grating ruler monitors electromagnetic vibration generator system moving-coil displacement, and output signal is converted to digital letter after serial encoder decodes
Number, it is then connected with controller, controller reads the reading of current absolute type linear grating ruler and electromagnetic vibration generator system dead-center position
It is poor that number is made, and exports the digital signal directly proportional to difference, and analog signal is converted into through digital analog converter, analog signal output and
Vibration displacement is directly proportional；The analog signal that the standard sine signal of the signal generator output is exported with digital analog converter is through subtracting
After musical instruments used in a Buddhist or Taoist mass, it is connected with the input terminal of the power amplifier；After the output terminal series multistage power resistor of the power amplifier,
It is connected with electromagnetic vibration generator system moving-coil.
PC machine is equipped between the digital analog converter and the controller, dual-port is equipped between PC machine and controller
RAM is written and read data.
The positive rigidity resilient supporting unit feedback control servo frequency of active is 1kHz~20kHz.
The multiple power levels resistance provides the power of 20 ohm, 50 ohm, 100 ohm, 200 ohm, 500 ohm different values
Resistance.
The technological innovation of the present invention and the good result of generation are：
(1) present invention builds Displacement Feedback using absolute type linear grating ruler.Absolute type linear grating ruler has non-contact
Measurement, high certainty of measurement, measurable shift value is big, performance is stable, without accumulated error the features such as, additionally with antijamming capability
By force, absolute position is immediately obtained after being powered can establish electromagnetic vibration generator system actual zero point again to the particular advantages such as zero, so as to
Solve the problems, such as that zero point is uncertain.
(2) thought that absolute displacement is fed back is introduced into calibration electromagnetic vibration generator system field by the present invention for the first time, proposes one
Kind realizes the electromagnetic vibration generator system control program of actively positive rigidity resilient support based on absolute position.With electromagnetic vibration generator system magnetic structure
Air gap centre position corresponding to absolute type linear grating ruler reading as zero point, absolute type linear grating ruler detection electromagnetic vibration
The displacement of dynamic platform moving component relative zero, the displacement signal is after scale operation, the standard sine with signal generator output
Signal carries out seeking difference operation, and deviation signal drives electromagnetic vibration generator system through power amplifier.This method can be generated from principle and position
The reciprocal Lorentz force of constant ratio is moved into, positive stiffness characteristics are realized using active method.This method can solve big displacement item
Rigidity is flexibly supported under part and there are problems that serious nonlinear characteristic.
(3) present invention proposes a kind of electromagnetic vibration generator system moving-coil series multistage power resistor technical solution, increases load impedance,
Make power amplifier be operated in voltage mode, output milliampere grade ultralow frequency electric current when with higher signal-to-noise ratio.
Description of the drawings
Fig. 1 is the electromagnetic vibration generator system schematic diagram that actively positive rigidity resilient support is realized based on absolute position feedback of the present invention
One embodiment；
Fig. 2 is the electromagnetic vibration generator system schematic diagram that actively positive rigidity resilient support is realized based on absolute position feedback of the present invention
Another one embodiment；
Fig. 3 is one embodiment of multiple power levels resistance of the present invention.
Piece number explanation in figure：Actively positive rigidity flexibly supports for 1 signal generator, 2 power amplifiers, 3 electromagnetic vibration generator systems, 4
Device, 5 multiple power levels resistance, 6 absolute type linear grating rulers, 7 serial encoders, 8 controllers, 9 digital analog converters, 10 subtractions
Device, 11PC machines, 12 two-port RAMs.
Specific embodiment
The specific embodiment of the present invention is described in detail below in conjunction with the accompanying drawings, and provides embodiment.
A kind of electromagnetic vibration generator system that actively positive rigidity resilient support is realized based on absolute position feedback, by signal generator 1,
Power amplifier 2, electromagnetic vibration generator system 3, actively positive rigidity resilient supporting unit 4 and multiple power levels resistance 5 form, and the active is just
Rigidity resilient supporting unit 4 includes absolute type linear grating ruler 6, serial encoder 7, controller 8, digital analog converter 9 and subtracts
Musical instruments used in a Buddhist or Taoist mass 10；The absolute type linear grating ruler 6 monitors 3 moving-coil displacement of electromagnetic vibration generator system, and output signal is decoded through serial encoder 7
After be converted to digital signal, be then connected with controller 8, controller 8 is by the reading and electromagnetism of current absolute type linear grating ruler 6
It is poor that 3 dead-center position reading of shake table is made, and exports the digital signal directly proportional to difference, is converted into simulating through digital analog converter 9
Signal, analog signal output are directly proportional to vibration displacement；The standard sine signal and digital-to-analogue conversion that the signal generator 1 exports
The analog signal that device 9 exports is connected after subtracter 10 with the input terminal of the power amplifier 2；The power amplifier 2
After output terminal series multistage power resistor 5, it is connected with 3 moving-coil of electromagnetic vibration generator system.
PC machine 11 is equipped between the digital analog converter 9 and the controller 8, is set between PC machine 11 and controller 8
There is two-port RAM 12 to be written and read data.
The positive 4 feedback control servo frequency of rigidity resilient supporting unit of active is 1kHz~20kHz.
The multiple power levels resistance 5 provides the work(of 20 ohm, 50 ohm, 100 ohm, 200 ohm, 500 ohm different values
Rate resistance.
One embodiment of the present of invention is provided with reference to Fig. 1.In the present embodiment, the reading of absolute type linear grating ruler 6
Head is mounted on 3 moving-coil of electromagnetic vibration generator system, and scale is fixed in the fixed component of electromagnetic vibration generator system 3.Absolute type linear grating
The reading head data of ruler 6 press BiSS agreement serial transmissions.Controller 8 is motion control card, and control serial encoder assists BiSS
View data are decoded into absolute position values.When 3 moving-coil of electromagnetic vibration generator system is located at stroke centre position, absolute type linear grating ruler 6 is read
Number is dead-center position.It is poor that controller 8 makees current 6 reading of absolute type linear grating ruler and dead-center position, and is multiplied by coefficient, makes number
Word magnitude is between -32767~32767.Digital analog converter 9 is 16 DAC output boards, and digital quantity is at -32767~32767 pairs
Answer -10~10V analog outputs.Controller 8 completes actively positive 4 feedback control of rigidity resilient supporting unit, and servo frequency can
Up to 20kHz.Signal generator 1 exports the standard sine signal of 0.1Hz, 5V amplitude, and the fortune that subtracts is exported with digital analog converter 9
It calculates, then the input terminal with power amplifier 2 is connected.Power amplifier 3 is operated in voltage mode, gain 10V/V.It is multistage
5 resistance value of power resistor selects 200 ohm, will load the power current that peak value is 0.25A on 3 moving-coil of electromagnetic vibration generator system, drives dynamic
Circle generates standard vibration.
Fig. 2 gives an alternative embodiment of the invention.In the present embodiment, it is equipped between digital analog converter 9 and controller 8
PC machine 11 is written and read data between PC machine 11 and controller 8 equipped with two-port RAM 12.PC machine 11 is quickly accessed with question and answer mode
The position data of absolute type linear grating ruler 6 in controller 8.PC machine 11 is by current 6 reading of absolute type linear grating ruler and zero point
It is poor that position is made, and is multiplied by coefficient, make digital quantity value -32767~32767 it, coefficient can at any time be changed in PC machine 11, from
And actively positive 4 stiffness coefficient of rigidity resilient supporting unit is adjusted, servo frequency may be up to 10kHz.
Fig. 3 is one embodiment of multiple power levels resistance 5.In the present embodiment, multiple power levels resistance 5 can provide 20 Europe
The power resistor of nurse, 50 ohm, 100 ohm, 200 ohm, 500 ohm different values can select above-mentioned resistance according to physical condition
One of value.
Claims (4)
1. a kind of electromagnetic vibration generator system that actively positive rigidity resilient support is realized based on absolute position feedback, by signal generator (1),
Power amplifier (2), actively electromagnetic vibration generator system (3), positive rigidity resilient supporting unit (4) and multiple power levels resistance (5) composition,
It is characterized in that：The positive rigidity resilient supporting unit (4) of active include absolute type linear grating ruler (6), serial encoder (7),
Controller (8), digital analog converter (9) and subtracter (10)；The absolute type linear grating ruler (6) monitors electromagnetic vibration generator system
(3) moving-coil displacement, output signal are converted to digital signal after serial encoder (7) decoding, are then connected with controller (8),
It is poor and defeated that controller (8) makees the reading of current absolute type linear grating ruler (6) and electromagnetic vibration generator system (3) dead-center position reading
Go out the digital signal directly proportional to difference, analog signal, analog signal output and vibration displacement are converted into through digital analog converter (9)
It is directly proportional；The standard sine signal of signal generator (1) output is with the analog signal of digital analog converter (9) output through subtraction
After device (10), it is connected with the input terminal of the power amplifier (2)；The output terminal series multistage work(of the power amplifier (2)
After rate resistance (5), it is connected with electromagnetic vibration generator system (3) moving-coil.
2. the electromagnetic vibration generator system according to claim 1 that actively positive rigidity resilient support is realized based on absolute position feedback,
It is characterized in that：PC machine (11), PC machine (11) and control are equipped between the digital analog converter (9) and the controller (8)
Between device (8) processed data are written and read equipped with two-port RAM (12).
3. the electric and magnetic oscillation that actively positive rigidity resilient support is realized based on absolute position feedback according to claim 1 and 2
Platform, it is characterised in that：Positive rigidity resilient supporting unit (4) the feedback control servo frequency of active is 1kHz~20kHz.
4. the electromagnetic vibration generator system according to claim 1 that actively positive rigidity resilient support is realized based on absolute position feedback,
It is characterized in that：The multiple power levels resistance (5) provides 20 ohm, 50 ohm, 100 ohm, 200 ohm, 500 ohm of different values
Power resistor.
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| CN201711020274.7A CN108051165A (en) | 2017-10-27 | 2017-10-27 | The electromagnetic vibration generator system of actively positive rigidity resilient support is realized based on absolute position feedback |
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| CN201711020274.7A CN108051165A (en) | 2017-10-27 | 2017-10-27 | The electromagnetic vibration generator system of actively positive rigidity resilient support is realized based on absolute position feedback |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109211507A (en) * | 2018-10-30 | 2019-01-15 | 脉创测控装备科技（苏州）有限公司 | Environmental test system, shake table position control and control method |
| CN110221101A (en) * | 2019-05-30 | 2019-09-10 | 浙江埃特斯力试验设备有限公司 | Low-frequency standard vibration platform based on overall-finished housing |
| CN111693235A (en) * | 2019-03-11 | 2020-09-22 | 中国水利水电科学研究院 | Low-frequency amplifying device of electromagnetic vibration table |
| CN112629564A (en) * | 2021-01-06 | 2021-04-09 | 哈尔滨工业大学 | High-acceleration high-precision linear vibration table |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109211507A (en) * | 2018-10-30 | 2019-01-15 | 脉创测控装备科技（苏州）有限公司 | Environmental test system, shake table position control and control method |
| CN111693235A (en) * | 2019-03-11 | 2020-09-22 | 中国水利水电科学研究院 | Low-frequency amplifying device of electromagnetic vibration table |
| CN110221101A (en) * | 2019-05-30 | 2019-09-10 | 浙江埃特斯力试验设备有限公司 | Low-frequency standard vibration platform based on overall-finished housing |
| CN110221101B (en) * | 2019-05-30 | 2021-08-06 | 浙江埃特斯力试验设备有限公司 | Low-frequency standard vibration table based on full-state feedback |
| CN112629564A (en) * | 2021-01-06 | 2021-04-09 | 哈尔滨工业大学 | High-acceleration high-precision linear vibration table |
| CN112629564B (en) * | 2021-01-06 | 2023-02-28 | 哈尔滨工业大学 | High-acceleration high-precision linear vibration table |
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