CN108254148A - Low-frequency electromagnetic vibration table system based on induction coil feedback control - Google Patents

Low-frequency electromagnetic vibration table system based on induction coil feedback control Download PDF

Info

Publication number
CN108254148A
CN108254148A CN201810060799.1A CN201810060799A CN108254148A CN 108254148 A CN108254148 A CN 108254148A CN 201810060799 A CN201810060799 A CN 201810060799A CN 108254148 A CN108254148 A CN 108254148A
Authority
CN
China
Prior art keywords
signal
feedback
frequency
induction coil
low
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201810060799.1A
Other languages
Chinese (zh)
Inventor
何闻
高宇
张旭飞
贾叔仕
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University ZJU
Original Assignee
Zhejiang University ZJU
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhejiang University ZJU filed Critical Zhejiang University ZJU
Priority to CN201810060799.1A priority Critical patent/CN108254148A/en
Publication of CN108254148A publication Critical patent/CN108254148A/en
Pending legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00Vibration-testing of structures; Shock-testing of structures
    • G01M7/02Vibration-testing by means of a shake table
    • G01M7/022Vibration control arrangements, e.g. for generating random vibrations

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Particle Accelerators (AREA)

Abstract

The invention discloses the low-frequency electromagnetic vibration table system based on induction coil feedback control, low-frequency electromagnetic vibration table system includes signal generator, speed feedback control device, power amplifier and low frequency electromagnetic shake table;There is driving coil and induction coil on the moving-coil of low-frequency vibration table, speed feedback control device includes feedback section and control unit, the induced voltage input feedback portion of induction coil, the reference signal of signal generator output and the feedback signal difference input control portion of feedback section output, control unit reference signal and feedback signal form control signal input driving coil.The present invention adds induction coil on jigging platform moving coil, shake table VELOCITY EXTRACTION is realized by the induced voltage for detecting induction coil, without directly detecting the equivalent resistance of driving coil, and the velocity measuring network of this method structure without the series resistance in driving coil and builds corresponding analog circuit, simplifies the structure of velocity extraction device.

Description

Low-frequency electromagnetic vibration table system based on induction coil feedback control
Technical field
The present invention relates to a kind of low-frequency electromagnetic vibration table systems.
Background technology
Electromagnetic vibration generator system has many advantages, such as that wide frequency range, controllability are good, output waveform precision is high, is widely used in product Analog vibration environmental test, vibration-measuring sensor calibration etc. fields.In order to further improve shake table in low-frequency range output wave The precision (reducing the distortion factor) of shape, need to usually build negative feed back control system.Negative feedback control is firstly the need of passing through vibrating sensing Device (acceleration, speed or displacement sensor) or other movement amount detecting devices detect to obtain the output vibration of electromagnetic vibration generator system Signal then using this signal as feedback signal, asks poor, deviation signal is after controller and power amplifier with input signal Excited vibration platform vibrates, and is finally completed the structure of closed-loop control system, realizes the negative-feedback to the shake table output waveform distortion factor Control.
Chinese patent 201210544489.X proposes a kind of low-frequency electrical based on autonomous relative velocity feed back control system Magnetic vibration platform system, the system construct negative feed back control system based on a kind of relative velocity extraction element.Relative velocity extracts The signal that device extracts asks poor after low-pass filter and the first proportional amplifier with signal generator output signal, partially Difference signal input power amplifier after PID controller adjusts, the output of power amplifier is as low frequency electromagnetic shake table Drive signal driving shake table output vibration.
The shortcomings that patent, is:
1st, since the equivalent d.c. resistance R of shake table driving coil can not be measured accurately, relative velocity extraction element In parameter K1Acquisition need to pass through more complicated adjustment process, increase the use difficulty of system;2nd, the device passes through structure Modeling intend circuit network extraction shake table amount of exercise, due to will in driving circuit series resistance, thermal losses is larger, no It is suitable for the shake table of high acceleration output.In addition, system is more complicated, the low-frequency noise of analog circuit can move shake table When generate low frequency wonder, reduce kinematic accuracy.3rd, the output signal size of relative velocity extraction element depends on driving coil Parameter, since the number of turn of driving coil is limited, thus output reflection relative velocity voltage swing it is relatively low, especially compared with low frequency Section, so as to affect control effect.
Invention content
The purpose of the present invention is to provide a kind of high low-frequency electromagnetic vibration table systems of motion control accuracy.
Low-frequency electromagnetic vibration table system based on induction coil feedback control, it is characterised in that:Low frequency electromagnetic shake table system System includes signal generator, speed feedback control device, power amplifier and low frequency electromagnetic shake table;The moving-coil of low-frequency vibration table Upper to have driving coil and induction coil, speed feedback control device includes feedback section and control unit, the induced electricity of induction coil Press input feedback portion, the reference signal of signal generator output and the feedback signal difference input control portion of feedback section output, control Portion's reference signal and feedback signal processed form control signal input driving coil.
Further, the diameter of the induction coil is far smaller than the diameter of driving coil.So as to increase induction coil The number of turn and total length improve the signal-to-noise ratio of the induced voltage of induction coil generation.
Further, induction coil is in parallel with partial pressure unit, the branch pressure voltage input feedback portion of partial pressure unit, partial pressure unit Input impedance tends to be infinitely great, meanwhile, divider resistance is also very big, avoids occurring parasite current in induction coil, makes driving line Parasite current is not coupled in circle, 0 is may be close to so as to flow to end the induced electricity for flowing through induction coil, avoids drawing for induction coil Enter the interference to electric current in driving coil.
Further, the feedback section of speed feedback control device includes signal correction module, feedback signal adjustment module and filter Wave device;Control unit includes subtracter and proportional controller, the induced voltage of induction coil after partial pressure input signal correcting module, Revise signal, revise signal input feedback signal adjustment module are obtained, feedback signal adjustment module carries out revise signal successively The phase compensation of frequency-division section and range-adjusting form system feedback signal, and the filtered device of system feedback signal is inputted as subtrahend Subtracter, the signal of signal generator output input subtracter as minuend, and the output signal of subtracter enters proportion adjustment Device, the control signal of the output signal of proportional controller as low frequency platform.
Further, feedback signal adjustment module includes frequency detecting unit, adjustable phase shifter and adjustable amplifier;Frequency is examined Unit is surveyed by sequentially connected comparator, counter and frequency controller composition, revise signal and reference signal input ratio jointly Compared with device, comparator exports the square-wave signal formed by system input signal and reference signal, square-wave signal and digital dock pulse Signal inputs counter, counter output system input signal cycle number N jointlyfWith the periodicity N of digital dock pulse signals, Frequency controller calculates the frequency values f for obtaining square-wave signalf,Wherein fsRepresent digital dock pulse signal Frequency values, frequency controller output phase shifting control pulse and amplitude adjustment control pulse;Phase shifting control pulse input adjustable phase shifter;It adjusts Width controls pulse input adjustable amplifier.
Further, adjustable phase shifter is in series by two-stage all-pass filter, and frequency detecting unit is inputted according to system to be believed Number frequency values ffPhase shifting control pulse is exported, phase shifting control Pulse Width Control adjustable phase shifter carries out phase benefit to feedback signal It repays, reduces the phase difference between input signal and feedback signal, improve feedback control effect.Adjustable phase shifter is in different frequency sections Phase shift value determine that step is as follows:
S1:In operating frequency range, to the pumping signal of shake table input different frequency, and negative feedback control system is built System.At different frequencies, out of phase adjustment is carried out to feedback signal, and detects respective frequencies, corresponding feedback signal phase item The precision characteristic of shake table output signal under part can be fed back according to the feedback signal phase for meeting shake table required precision Signal required phase shift value at different frequencies.The operating frequency range of shake table is divided into k-1 sections, is expressed as fn≤ f < fn+1, n=1,2,3 ... k-1, the standard of segmentation are identical for the phase shift value of the revise signal in this segmentation;Phase shift value herein The identical difference referred in the frequency segmentation, between the phase shift value of each frequency is in the deviation range of permission;
S2:Successively to each frequency segmentation, take in the frequency segmentation, the average value of the phase shift value of each frequency is as the frequency The phase shift value of rate segmentationWithAs fnThe phase shift value of the adjustable phase shifter of frequency segmentation;
S3:To fnThe phase shift value of frequency segmentation is expressed as:
;Wherein:R2For the resistance value of the digital potentiometer in first order all-pass filter, R3For second level all-pass filter In digital potentiometer resistance value;
S4:Enable R2=R3And step S2 and S3 are combined, acquire the R corresponding to each frequency segmentation2、R3Value, to each frequency It is segmented, with R2、R3Value is calculated as reference to be needed to input the digital potentiometer in first order all-pass filter and the second level The phase shifting control pulse number of digital potentiometer in all-pass filter, phase shifting control pulse number control adjustable phase shifter generate Respective frequencies segmentation phase shift value.
Further, revise signal input adjustable phase shifter, the output terminal of adjustable phase shifter and the input terminal of adjustable amplifier It is connected.
Alternatively, revise signal inputs adjustable amplifier, the output terminal of adjustable amplifier and the input terminal phase of adjustable phase shifter Even.
Further, adjustable amplifier is in series by in-phase proportion amplifying circuit and partial pressure potential meter, is used to implement feedback The amplification or attenuation of signal, obtain suitable depth of feedback.Adjustable amplifier determines step such as in the gain of different frequency sections Under:
1), in operating frequency range, to the pumping signal of shake table input different frequency, and negative feedback control system is built System.At different frequencies, apply different gains to feedback signal amplitude, and detect respective frequencies, corresponding feedback signal gain Under the conditions of shake table output signal precision characteristic, can be obtained instead according to the feedback signal gain for meeting shake table required precision Feedback signal required gain at different frequencies.The operating frequency range of shake table is divided into (k ' -1) section, is expressed as:
fm≤ f < fm+1, m=1,2,3 ... k ' -1;
2), each frequency segmentation is taken in current frequency segmentation, the average value of the gain of each frequency is as current successively The yield value p of frequency segmentationm
3), the yield value of each frequency range is expressed as:
Wherein, R6It is the resistance value of the feedback resistance in scaling circuit in the same direction, R7It is the all-in resistance of partial pressure potential meter Value, R7wIt is the partial pressure resistance value of partial pressure potential meter;
4) the resistance value R of the fixed resistance of in-phase proportion amplifying circuit, is determined5, it is to need to believe to judge current frequency segmentation Number amplification or signal attenuation, take R when needing signal being amplified7w=R7, acquire R6;With R6Value and R7wAs reference, Being calculated needs the tune of the amplitude adjustment control pulse number for inputting feedback resistance in scaling circuit in the same direction and partial pressure potential meter Width controls pulse number, so as to control the adjustment of the feedback signal amplitude of adjustable amplifier realization corresponding frequency band;
R is taken when needing to decay signal6=0, acquire required R7w;With R6Value and R7wNeeds are calculated as reference Input the amplitude adjustment control pulse of the amplitude adjustment control pulse number and partial pressure potential meter of feedback resistance in scaling circuit in the same direction Number, so as to control the adjustment of the feedback signal amplitude of adjustable amplifier realization corresponding frequency band.
Further, the speed feedback control device further includes proportional controller, and the proportional controller is arranged on subtraction Between device and power amplifier.
The present invention operation principle be:Induction coil inspection is wound by being on the part in uniform magnetic field in moving component Output vibration velocity of the shake table in low-frequency range is surveyed, and speed feedback control device is constructed based on this, which can divide The amplitude and phase for the shake table motor message that section obtains detection are adjusted, after the signal adjusted seeks difference with input signal Obtain deviation signal, the deviation signal only need to pass through ratio enlargement link can input power amplifier, driving shake table output By the vibration signal of accurate negative feedback control.Therefore, low frequency electromagnetic vibration bench control system proposed by the present invention, which has, simplifies Speed detector, further improve the negative feedback control effect to low frequency electromagnetic shake table output waveform precision, and drop Low feedback controller is built and the difficulty of parameter adjustment.
The advantage of the invention is that:
1st, induction coil is added on jigging platform moving coil, shake table speed is realized by the induced voltage for detecting induction coil Extraction, without directly detecting the equivalent resistance of driving coil, and the velocity measuring network of this method structure is without in driving line Series resistance and corresponding analog circuit is built on circle, simplify the structure of velocity extraction device, it is often more important that will not drive Moving winding circuit introduces low-frequency noise, reduces the low frequency wonder of shake table during exercise.
2nd, the number of inductive coil turns added on jigging platform moving coil is more, and the velocity voltage signal amplitude of output is larger, have compared with High signal-to-noise ratio, is conducive to feedback control.
3rd, feedback signal is formed after revise signal being carried out phase shift and amplitude modulation compensation, feedback signal has a degree of phase Position compensation, and there is appropriate depth of feedback at different frequencies, improve the precision of the output waveform of shake table.
4th, the working frequency of shake table is segmented, phase shift and amplitude modulation is carried out respectively to each frequency segmentation, without to each Frequency independently carries out phase shift and amplitude modulation, reduce feedback controller build and the difficulty of parameter adjustment.
Description of the drawings
Fig. 1 is the structural diagram of the present invention.
Fig. 2 is the principle of the present invention figure.
Fig. 3 is feedback signal adjustment module structure diagram of the present invention.
Fig. 4 is the structure chart of adjustable phase shifter of the present invention and adjustable amplifier.
Specific embodiment
The present invention is further described with reference to specific embodiment, but does not limit the invention to these tools Body embodiment.One skilled in the art would recognize that present invention encompasses may include in Claims scope All alternatives, improvement project and equivalent scheme.
Referring to Fig. 1, Fig. 2, in embodiment 1, based on the low-frequency electromagnetic vibration table system of induction coil feedback control, low frequency Electromagnetic vibration generator system system includes signal generator, speed feedback control device, power amplifier and low frequency electromagnetic shake table;Low frequency There is driving coil and induction coil on the moving-coil of shake table.
The driving coil is wound in induction coil in the same winding slot of shake table moving component 1 jointly, can also Be induction coil from driving coil wound side by side in the different winding slots of shake table moving component, and ensure induction coil with drive Moving winding is coaxial, and among even air gap magnetic field.Speed feedback control device includes feedback section and control unit, induction coil Induced voltage input feedback portion, signal generator output reference signal and feedback section output system feedback signal ufbRespectively Input control portion, control unit reference signal and system feedback signal ufbForm control signal input driving coil.The sensing The diameter of coil is far smaller than the diameter of driving coil, so as to increase the number of turn of induction coil and total length, improves sensing The signal-to-noise ratio for the induced voltage that coil generates.Induction coil is in parallel with partial pressure unit, the branch pressure voltage input feedback of partial pressure unit Portion, the input impedance of partial pressure unit tend to be infinitely great.Partial pressure unit is used to extract the induced voltage of induction coil both ends generation, and It is handled by signal correction module, obtains the speed signal u of shake tableo.Divider resistance tends to be infinitely great, avoids feeling It answers and occurs parasite current in coil, make not couple parasite current in driving coil, so as to make to flow through the sensing electric current of induction coil As close possible to 0, the interference being introduced into electric current in driving coil of induction coil is avoided.
Principle based on induction coil detection low frequency electromagnetic shake table output vibration velocity is:
For conventional low frequency electromagnetic shake table, driving coil (loop length ld) resistance R can be reduced todWith inductance Ld Cascaded structure.Apply voltage u when applying sine to driving coil both endsi, sinusoidal current i can be generated in driving coild, vibrating Under the action of the even air gap magnetic field (magnetic induction intensity B) that platform magnetic structure generates, driving coil is by sinusoidal Ampere force It acts on and generates sinusoidal vibration.Since driving coil and shake table moving component are fixedly mounted, so shake table moving component is defeated Go out vibration signal.It is typical Mechanical & Electrical Combination System in view of electromagnetic vibration generator system, when shake table moving component, which exports, to be vibrated, drives Moving winding generates and vibration velocityFor the displacement of shake table moving component,First derivative for x) directly proportional induced electricity Kinetic potential
Similarly, induction coil (length ls) resistance R can also be reduced tosWith inductance LsCascaded structure.In view of the line of induction Circle is co-axially mounted with driving coil, when shake table moving component, which exports, to be vibrated, induction coilAlso generation and vibration velocityInto The induced electromotive force of direct ratio
According to stable state flux coupled principle, it can be assumed that induction coil 12 is intercoupled with driving coil 11 by mutual inductance M. Further, the vibration processes of shake table moving component 1 can be reduced to mass-spring-damper system single-degree of freedom vibration, m, k, C is respectively equivalent mass, equivalent stiffness and equivalent damping, as shown in figure 3, obtaining whole mechanical-electric coupling relationship and being
In formula, usFor the induced voltage that 12 both ends of induction coil generate, isTo flow through the sensing electric current of induction coil 12, t is It is sometime instantaneous,WithThe respectively first derivative of x and second dervative.The partial pressure unit has great impedance, from And make to flow through the sensing electric current i of induction coil 12sAmplitude as close possible to 0, it is believed that is≈ 0, further, when vibration frequency When rate f is relatively low, there is dis/ dt=2 π fis≈ 0 avoids the introducing of induction coil 12 to the output vibration of shake table moving component 1 Interference.Therefore, formula (1) can be further simplified as
Shake table input voltage u can be calculated based on the 1st formula in (2) and the 3rd formulaiWith exporting vibration velocityIt Between transmission function GviFor
In formula, X (s), Ui(s) it is respectively x, uiLaplace transform.In addition input electricity can also be acquired based on formula (2) Press uiWith induced voltage usBetween transmission function be
In formula, Us(s) it is usLaplace transform.Comparison expression (3) can be obtained with formula (4)
It enables
For the transmission function of signal correction unit, then it is defeated shake table can be obtained by induction coil output voltage according to formula (5) Go out speed signal.And analog circuit or number are easily passed through as it can be seen that the signal correction unit is a second-order system by formula (6) Word signal processing unit is realized.Induced voltage through with after the signal correction resume module of transmission function shown in formula (6) with vibration Platform speed is directly proportional, realizes shake table speed signal uoExtraction.In the present invention, low frequency electromagnetic shake table vibration velocity is examined It surveys device not having to concatenate pure resistance and structure complicated circuit system with shake table driving coil, avoids the complexity to systematic parameter Adjustment process further simplifies system structure and reduces the detection difficulty of vibration velocity.
As shown in Figure 1, the feedback section of speed feedback control device include signal correction module, feedback signal adjustment module, And wave filter;Control unit includes subtracter J1 and proportional controller, and the induced voltage of the induction coil input signal after partial pressure is repaiied Positive module obtains revise signal, revise signal input feedback signal adjustment module, feedback signal adjustment module by revise signal according to The secondary phase compensation for carrying out frequency-division section and range-adjusting form system feedback signal ufb, system feedback signal ufbFiltered device is made Subtracter J1 is inputted for subtrahend, the signal of signal generator output inputs subtracter J1, the output of subtracter J1 as minuend Signal enters proportional controller, the control signal of the output signal of proportional controller as low frequency platform.When low frequency electromagnetic shake table When moving component exports vibration signal, induction coil both ends generate induced voltage, and the induced voltage is through signal correction resume module It is directly proportional to the vibration velocity of low frequency electromagnetic shake table moving component afterwards, it is real by the extraction to signal correction module output voltage Now to the detection of moving component output vibration velocity.
As shown in figure 3, feedback signal adjustment module includes frequency detecting unit and adjustable phase shifter;Frequency detecting unit by Its composition of sequentially connected comparator, counter and FREQUENCY CONTROL, revise signal and the common input comparator of reference signal, compare The system input signal that device output is formed by revise signal and reference signal, square-wave signal and digital dock pulse signal are jointly defeated Enter counter, counter output system input signal cycle number NfWith the periodicity N of digital dock pulse signals, frequency controller Calculate the frequency values f for obtaining system input signalf,Wherein fsRepresent the frequency values of digital dock pulse signal; Phase shifting control pulse input adjustable phase shifter.Counter passes through the digital signal based on FPGA or DSP structures with frequency controller Processing unit is realized.
System input signal and given reference-input signal to comparator inputted vibration platform, when system input signal Comparator output high level when amplitude is higher than the amplitude of reference-input signal, comparator on the contrary export low level, as a result, comparator Square-wave signal is exported, and the frequency of the square-wave signal is identical with system input signal.The frequency of square-wave signal is unknown at this time, because This, in square-wave signal and digital dock pulse signal colleague's input counter, counter counts the periodicity of square-wave signal, and counts The frequency of word clock, just can be according to the periodicity of square-wave signal and the periodicity of dagital clock signal it is known that in same time Ratio calculate the frequency of square wave, the frequency of system input signal is learnt from the frequency of square wave, so as to correspond to corresponding frequency Segmentation.
Referring to Fig. 4, adjustable phase shifter is in series by two-stage all-pass filter, filtered electrical in first order all-pass wave filtering circuit It is the first digital potentiometer to hinder (filter resistance refers to the resistance in the RC circuits played a filtering role), and resistance value is expressed as R2, second Filter resistance is the second digital potentiometer in grade all-pass wave filtering circuit, and resistance value is expressed as R3, the first digital potentiometer and Two digital potentiometers are adjustable digital potentiometer, and frequency detecting unit is according to the frequency values f of system input signalfExport phase shift Pulse is controlled, exports the first digital potentiometer of phase shifting control Pulse Width Control of corresponding number and the output pair of the second digital potentiometer The resistance value answered can realize 0~360 ° of phase shift to the signal for inputting adjustable phase shifter.Adjustable phase shifter is in different frequency sections Phase shift value determines that step is as follows:
S1:In operating frequency range, to the pumping signal of shake table input different frequency, and negative feedback control system is built System.At different frequencies, out of phase adjustment is carried out to feedback signal, and detects respective frequencies, corresponding feedback signal phase item The precision characteristic of shake table output signal under part can be fed back according to the feedback signal phase for meeting shake table required precision Signal required phase shift value at different frequencies.The operating frequency range of shake table is divided into k-1 sections, is expressed as fn≤ f < fn+1, n=1,2,3 ... k-1, the standard of segmentation are identical for the phase shift value of the revise signal in this segmentation;Phase shift value herein The identical difference referred in the frequency segmentation, between the phase shift value of each frequency is in the deviation range of permission;
S2:Successively to each frequency segmentation, take in the frequency segmentation, the average value of the phase shift value of each frequency is as the frequency The phase shift value of rate segmentationWithAs fnThe phase shift value of the adjustable phase shifter of frequency segmentation;
S3:To fnThe phase shift value of frequency segmentation is expressed as:
;Wherein:R2For the resistance value of the digital potentiometer in first order all-pass filter, R3For second level all-pass filter In digital potentiometer resistance value;
S4:Enable R2=R3And step S2 and S3 are combined, acquire the R corresponding to each frequency segmentation2、R3Value, to each frequency It is segmented, with R2、R3Value is calculated as reference to be needed to input the digital potentiometer in first order all-pass filter and the second level The phase shifting control pulse number of digital potentiometer in all-pass filter, the respective frequencies segmentation that control adjustable phase shifter generates Phase shift value.
The amplitude adjustment control arteries and veins of the corresponding number of system input signal frequency values output that frequency detecting unit is obtained according to detection Punching control third digital potentiometer and the corresponding resistance value of the 4th digital potentiometer output, are realized to inputting adjustable amplifier signal width The adjustment of value.Counter output system input signal cycle number NfWith the periodicity N of digital dock pulse signals, frequency controller Calculate the frequency values f for obtaining system input signalf,Wherein fsRepresent the frequency values of digital dock pulse signal, Frequency controller exports amplitude adjustment control pulse;Amplitude adjustment control pulse input adjustable amplifier.Adjustable amplifier is put by in-phase proportion Big circuit and partial pressure potential meter connect to be formed, and the gain of the different frequency sections of adjustable amplifier determines that step is as follows:
1), in operating frequency range, to the pumping signal of shake table input different frequency, and negative feedback control system is built System.At different frequencies, apply different gains to feedback signal amplitude, and detect respective frequencies, corresponding feedback signal gain Under the conditions of shake table output signal precision characteristic, can be obtained instead according to the feedback signal gain for meeting shake table required precision Feedback signal required gain at different frequencies.The operating frequency range of shake table is divided into (k ' -1) section, is expressed as:
fm≤ f < fm+1, m=1,2,3 ... k ' -1;
2), each frequency segmentation is taken in current frequency segmentation, the gain average value of each frequency is as current frequency successively The gain p of rate segmentationm
3), the gain of each frequency range is expressed as:
Wherein, R6It is the resistance value of the feedback resistance in scaling circuit in the same direction, R7It is the all-in resistance of partial pressure potential meter Value, R7wIt is the partial pressure resistance value of partial pressure potential meter;
4) the resistance value R of the fixed resistance of in-phase proportion amplifying circuit, is determined5, it is to need to believe to judge current frequency segmentation Number amplification or signal attenuation, take R when needing signal being amplified7w=R7, acquire R6;With R6Value and R7wAs reference, Being calculated needs the tune of the amplitude adjustment control pulse number for inputting feedback resistance in scaling circuit in the same direction and partial pressure potential meter Width controls pulse number, so as to control the adjustment of the feedback signal amplitude of adjustable amplifier realization corresponding frequency band;
R is taken when needing to decay signal6=0, acquire required R7w;With R6Value and R7wNeeds are calculated as reference Input the amplitude adjustment control pulse of the amplitude adjustment control pulse number and partial pressure potential meter of feedback resistance in scaling circuit in the same direction Number, so as to control the adjustment of the feedback signal amplitude of adjustable amplifier realization corresponding frequency band.
In one embodiment, revise signal input adjustable phase shifter, the output terminal and adjustable amplifier of adjustable phase shifter Input terminal be connected.
In another embodiment, revise signal input adjustable amplifier, the output terminal and Adjustable Phase Shift of adjustable amplifier The input terminal of device is connected.
Feedback signal adjustment module proposed by the present invention can carry out certainly vibration bench control system feedback signal with frequency-division section Adjustment is adapted to, makes feedback signal that there is the amplitude and phase for meeting negative feed back control system needs.It was adjusted based on this device Signal is as feedback signal and carrys out the input signal of automatic signal generator difference is asked to obtain deviation signal, the deviation signal only need by Ratio enlargement link can input power amplifier, driving shake table output by accurate negative feedback control vibration signal.Base The negative feedback control effect to shake table output waveform precision can be further improved in the control system of this structure, is reduced anti- Feedback controller is built and parameter regulation difficulty.
The speed feedback control device further includes proportional controller, and the proportional controller is arranged on subtracter and power Between amplifier.
The present invention operation principle be:Induction coil inspection is wound by being on the part in uniform magnetic field in moving component Output vibration velocity of the shake table in low-frequency range is surveyed, and speed feedback control device is constructed based on this, which can divide The amplitude and phase for the shake table motor message that section obtains detection are adjusted, after the signal adjusted seeks difference with input signal Obtain deviation signal, the deviation signal only need to pass through ratio enlargement link can input power amplifier, driving shake table output By the vibration signal of accurate negative feedback control.Therefore, low frequency electromagnetic vibration bench control system proposed by the present invention, which has, simplifies Speed detector, further improve the negative feedback control effect to low frequency electromagnetic shake table output waveform precision, and drop Low feedback controller is built and the difficulty of parameter adjustment.

Claims (9)

1. the low-frequency electromagnetic vibration table system based on induction coil feedback control, which is characterized in that fed back and controlled based on induction coil The low-frequency electromagnetic vibration table system of system, it is characterised in that:Low-frequency electromagnetic vibration table system includes signal generator, velocity feedback control Device processed, power amplifier and low frequency electromagnetic shake table;There is driving coil and induction coil, speed on the moving-coil of low-frequency vibration table It spends feed back control system and includes feedback section and control unit, the induced voltage input feedback portion of induction coil, signal generator output Reference signal and feedback section output feedback signal difference input control portion, control unit formed with reference signal and feedback signal Control signal input driving coil.
2. the low-frequency electromagnetic vibration table system based on induction coil feedback control according to claims 1, feature exist In the diameter of the induction coil is far smaller than the diameter of driving coil.
3. the low-frequency electromagnetic vibration table system based on induction coil feedback control according to claims 2, feature exist In induction coil is in parallel with partial pressure unit, and the branch pressure voltage input feedback portion of partial pressure unit, the input impedance of partial pressure unit tends to It is infinitely great.
4. the low-frequency electromagnetic vibration table system based on induction coil feedback control according to claims 3, feature exist In the feedback section of speed feedback control device includes signal correction module, feedback signal adjustment module and wave filter;Control unit Comprising subtracter and proportional controller, the induced voltage of induction coil after partial pressure input signal correcting module, obtain and correct letter Number, revise signal is carried out the phase of frequency-division section by revise signal input feedback signal adjustment module, feedback signal adjustment module successively Position compensation and range-adjusting form system feedback signal, and the filtered device of system feedback signal inputs subtracter, signal as subtrahend The signal of generator output inputs subtracter as minuend, and the output signal of subtracter enters proportional controller, proportion adjustment Control signal of the output signal of device as low frequency platform.
5. the low-frequency electromagnetic vibration table system based on induction coil feedback control according to claims 4, feature exist In feedback signal adjustment module includes frequency detecting unit, adjustable phase shifter and adjustable amplifier;Frequency detecting unit is by successively The comparator of connection, counter and frequency controller composition, revise signal and the common input comparator of reference signal, comparator are defeated Go out the square-wave signal formed by system input signal and reference signal, square-wave signal inputs meter jointly with digital dock pulse signal Number device, counter output system input signal cycle number NfWith the periodicity N of digital dock pulse signals, frequency controller calculating Obtain the frequency values f of square-wave signalf,Wherein fsRepresent the frequency values of digital dock pulse signal, FREQUENCY CONTROL Device exports phase shifting control pulse and amplitude adjustment control pulse;Phase shifting control pulse input adjustable phase shifter;Amplitude adjustment control pulse input Adjustable amplifier.
6. the low-frequency electromagnetic vibration table system based on induction coil feedback control according to claims 5, feature exist In adjustable phase shifter is in series by two-stage all-pass filter.
7. the low-frequency electromagnetic vibration table system based on induction coil feedback control according to claims 6, feature exist In revise signal input adjustable phase shifter, the output terminal of adjustable phase shifter is connected with the input terminal of adjustable amplifier, alternatively, repairing Positive signal inputs adjustable amplifier, and the output terminal of adjustable amplifier is connected with the input terminal of adjustable phase shifter.
8. the low-frequency electromagnetic vibration table system based on induction coil feedback control according to claims 7, feature exist In adjustable amplifier is in series by in-phase proportion amplifying circuit and partial pressure potential meter.
9. the low-frequency electromagnetic vibration table system based on induction coil feedback control according to claims 8, feature exist In the speed feedback control device further includes proportional controller, and the proportional controller is arranged on subtracter and power amplification Between device.
CN201810060799.1A 2018-01-22 2018-01-22 Low-frequency electromagnetic vibration table system based on induction coil feedback control Pending CN108254148A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810060799.1A CN108254148A (en) 2018-01-22 2018-01-22 Low-frequency electromagnetic vibration table system based on induction coil feedback control

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810060799.1A CN108254148A (en) 2018-01-22 2018-01-22 Low-frequency electromagnetic vibration table system based on induction coil feedback control

Publications (1)

Publication Number Publication Date
CN108254148A true CN108254148A (en) 2018-07-06

Family

ID=62742082

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810060799.1A Pending CN108254148A (en) 2018-01-22 2018-01-22 Low-frequency electromagnetic vibration table system based on induction coil feedback control

Country Status (1)

Country Link
CN (1) CN108254148A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112098026A (en) * 2020-09-08 2020-12-18 杭州亿恒科技有限公司 Noise and loop detection accelerating method and system
CN112946730A (en) * 2021-01-26 2021-06-11 哈尔滨工程大学 Low-frequency large dynamic double closed-loop feedback method for optical fiber seismometer

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4297888A (en) * 1979-02-28 1981-11-03 Hitachi, Ltd. Stability control system for vibration test device
JP2003285008A (en) * 2002-01-23 2003-10-07 Inr Kenkyusho:Kk Ultrasonic wave generation method and apparatus therefor
CN1812246A (en) * 2006-01-04 2006-08-02 天津大学 Non-contact liquid medium ultrasound wave electric machine frequency tracking speed control system
CN102980653A (en) * 2012-12-13 2013-03-20 浙江大学 Low-frequency electromagnetic vibration table system based on autonomous relative speed feedback control device
CN103645384A (en) * 2013-11-18 2014-03-19 国家电网公司 Grounding resistor test power frequency interference inhibition apparatus
CN203874979U (en) * 2014-05-29 2014-10-15 中国地震局工程力学研究所 Double-moving-coil servo ultra-low frequency rotary vibrating table
CN208109369U (en) * 2018-01-22 2018-11-16 浙江大学 Low-frequency electromagnetic vibration table system based on induction coil feedback control

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4297888A (en) * 1979-02-28 1981-11-03 Hitachi, Ltd. Stability control system for vibration test device
JP2003285008A (en) * 2002-01-23 2003-10-07 Inr Kenkyusho:Kk Ultrasonic wave generation method and apparatus therefor
CN1812246A (en) * 2006-01-04 2006-08-02 天津大学 Non-contact liquid medium ultrasound wave electric machine frequency tracking speed control system
CN102980653A (en) * 2012-12-13 2013-03-20 浙江大学 Low-frequency electromagnetic vibration table system based on autonomous relative speed feedback control device
CN103645384A (en) * 2013-11-18 2014-03-19 国家电网公司 Grounding resistor test power frequency interference inhibition apparatus
CN203874979U (en) * 2014-05-29 2014-10-15 中国地震局工程力学研究所 Double-moving-coil servo ultra-low frequency rotary vibrating table
CN208109369U (en) * 2018-01-22 2018-11-16 浙江大学 Low-frequency electromagnetic vibration table system based on induction coil feedback control

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112098026A (en) * 2020-09-08 2020-12-18 杭州亿恒科技有限公司 Noise and loop detection accelerating method and system
CN112098026B (en) * 2020-09-08 2022-08-09 杭州亿恒科技有限公司 Noise and loop detection accelerating method and system
CN112946730A (en) * 2021-01-26 2021-06-11 哈尔滨工程大学 Low-frequency large dynamic double closed-loop feedback method for optical fiber seismometer
CN112946730B (en) * 2021-01-26 2023-07-21 哈尔滨工程大学 Low-frequency large-dynamic double-closed-loop feedback method for fiber seismometer

Similar Documents

Publication Publication Date Title
US10623865B2 (en) System and method for applying a sound signal to a multi coil electrodynamic acoustic transducer
JP4700699B2 (en) Method for detecting an object enclosed in a medium, and measuring apparatus for carrying out the detection method
CN108333917A (en) Frequency dividing detector for low-frequency electromagnetic vibration table system feedback control
JPH0919191A (en) Positioning method for rotor in rotational motor or linear motor
US10397706B2 (en) Method for avoiding an offset of a membrane of a electrodynamic acoustic transducer
CN104035329A (en) Automatic vibration calibration system and calibration method
CN108254148A (en) Low-frequency electromagnetic vibration table system based on induction coil feedback control
US11374522B2 (en) Adaptive model feedback for haptic controllers
CN110221101B (en) Low-frequency standard vibration table based on full-state feedback
CN111929492A (en) Full-digital fluxgate type closed-loop current sensor and current signal acquisition method thereof
CN104237818A (en) Gradient system and gradient magnetic field control method and MRI (magnetic resonance imaging) system
CN208109369U (en) Low-frequency electromagnetic vibration table system based on induction coil feedback control
CN111541442A (en) Method for resolving inductance value of proximity sensor
CN208334934U (en) Frequency dividing detector for low-frequency electromagnetic vibration table system feedback control
US20020050898A1 (en) Method and arrangement for determining the position of an electromagnetic actuator
CN108344494A (en) Low frequency electromagnetic shake table movement velocity detection device based on induction coil
CN208109253U (en) Low frequency electromagnetic shake table movement velocity detection device based on induction coil
CN103033255B (en) Extraction device for relative motion capacity of low-frequency electromagnetic vibration generator system
CN102980653B (en) Low-frequency electromagnetic vibration table system based on autonomous relative speed feedback control device
CN105765337B (en) Inductive measuring probe and the method for operating induction type measuring probe
CN108254147B (en) Frequency-division amplitude modulation system for feedback signal of vibrating table
CN109723719B (en) Differential detection type self-sensing electromagnetic bearing and implementation method thereof
EP2980429A1 (en) Improved position detection device of amb
CN203100890U (en) Low frequency electromagnetic vibrating table system based on autonomous relative speed feedback control device
CN108233922A (en) Shake table feedback signal frequency-division section phase-shift system

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination