CN206311148U - A kind of vortex signal detection means of the accidental resonance with feedforward controller - Google Patents
A kind of vortex signal detection means of the accidental resonance with feedforward controller Download PDFInfo
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- CN206311148U CN206311148U CN201621449641.6U CN201621449641U CN206311148U CN 206311148 U CN206311148 U CN 206311148U CN 201621449641 U CN201621449641 U CN 201621449641U CN 206311148 U CN206311148 U CN 206311148U
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Abstract
The utility model discloses a kind of vortex signal detection means of the accidental resonance with feedforward controller, including vortex flow sensors, change of scale module, feedforward control module, microcontroller, output display module and power module；The power module is respectively change of scale module, feedforward control module and microcontroller and provides operating voltage；The vortex flow sensors are connected with change of scale module, and the change of scale module is connected with feedforward control module, and the change of scale module, feedforward control module and output display module are connected with microcontroller.The utility model can effectively improve Signal-to-Noise by feedforward control module, in the treatment of follow-up accidental resonance, can be more beneficial for detecting flux of vortex street characteristic frequency, make detection vortex signal more efficient.
Description
Technical field
The utility model is related to a kind of vortex signal detecting system, more particularly to a kind of accidental resonance with feedforward controller
Vortex signal detection means.
Background technology
Accidental resonance is the cooperative phenomenon in the presence of nonlinear system, noise, small-signal three.Generally all think noise
It is a kind of harmful interference, really, when useful signal is detected, noise can be impacted to many detecting systems, be led to not just
Often detection.But in stochastic resonance system, when noise, signal and nonlinear system are reached under certain collaboration situation, with noise
Intensity gradually increases from small, and the signal to noise ratio of output significantly strengthens.This phenomenon provides ten for accidental resonance detection small-signal
Divide useful means.Accidental resonance is to utilize for the portion of energy of noise to be converted to signal energy so as to detect the side of small-signal
Method.
Actual Detection of Weak Signals has two big difficult points.First, small-signal is detected under conditions of low signal-to-noise ratio.Due to spy
Reference number itself it is very faint and meanwhile external noise intensity again than larger, signal will certainly be caused to be buried in noise, cause difficulty
To examine and determine；Second, the real-time and rapidity of signal detection.In Practical Project utilization, the duration of signal acquisition, signal
Data length be often restricted.Therefore, the improvement of stochastic resonance system is extremely urgent.
Utility model content
The purpose of this utility model is directed to the deficiency of existing vortex signal detection technique, there is provided a kind of band feedforward control
The vortex signal detection means of the accidental resonance of device.
The purpose of this utility model is achieved through the following technical solutions：A kind of accidental resonance with feedforward controller
Vortex signal detection means, including vortex flow sensors, change of scale module, feedforward control module, microcontroller, output are aobvious
Show module and power module；The power module is respectively change of scale module, feedforward control module and microcontroller and carries
For operating voltage；The vortex flow sensors are connected with change of scale module, the change of scale module and feedforward control mould
Block is connected, and the change of scale module, feedforward control module and output display module are connected with microcontroller.
Further, the power module provides+12V voltage-stabilized power supplies, -12V voltage-stabilized power supplies, 5V voltage-stabilized power supplies and 3.3V
Voltage-stabilized power supply.
Further, the output display module selects TFTLCD liquid crystal displays.
Further, the change of scale module include resistance R1, slide rheostat R2, slide rheostat R3, resistance R4,
Resistance R5, voltage-regulator diode D1, voltage-regulator diode D2, amplifier U1 and amplifier U2；
Wherein ,+12V source of stable pressure respectively with the positive supply input and the positive supply input phase of amplifier U2 of amplifier U1
Even；The negative power end of -12V source of stable pressure one end, the negative power end of amplifier U1 and amplifier U2 respectively with resistance R1 is connected；Electricity
The other end for hindering R1 is connected with coil one end of slide rheostat R2, the coil other end ground connection of slide rheostat R2, slides and becomes
The sliding end of resistance device R2 is connected with the normal phase input end of amplifier U1；The inverting input of amplifier U1 is connected with output end；Resistance R4
One end be connected with coil one end of slide rheostat R3 and the output end of amplifier U1 respectively, the sliding end of slide rheostat R3 and
The output end of amplifier U2 is connected；The other end of resistance R4 is connected with the inverting input of amplifier U2；The other end of resistance R5 and whirlpool
The output signal VIN ends of street flow sensor are connected, and the other end is connected with the normal phase input end of amplifier U2；Voltage-regulator diode D1 with
Voltage-regulator diode D2 Opposite direction connections, one of voltage-regulator diode D2 inputs are connected with 2 output ends of amplifier U, the pole of voltage stabilizing two
Pipe D1 inputs end is grounded；The output end of amplifier U2 as yardstick control module output end, the output end of yardstick control module
It is connected with the I/O ports of microcontroller.
Further, the feedforward control module include resistance R6, slide rheostat R7, resistance R8, slide rheostat R9,
Resistance R10, resistance R11, voltage-regulator diode D3, voltage-regulator diode D4, amplifier U3, amplifier U4 and amplifier U5；
Wherein ,+12V source of stable pressure respectively with resistance R6, the positive supply input of amplifier U3, amplifier U4 positive supply input
And the positive supply input of amplifier U5 is connected；- 12V source of stable pressure coil one end respectively with slide rheostat R7, amplifier U3
The negative power end of negative power end, the negative power end of amplifier U4 and amplifier U5 is connected；The other end and slide rheostat of resistance R6
The coil other end of R7 is connected, and the sliding end of slide rheostat R7 is connected with the normal phase input end of amplifier U3；Amplifier U3's is anti-phase
Input is connected with output end；One end of resistance R8 is connected with the output end of amplifier U3, the anti-phase input of the other end and amplifier U4
End is connected；The inverting input of amplifier U5 is connected with output end；Coil one end of slide rheostat R9 is anti-phase defeated with amplifier U5
Enter end to be connected, sliding end is connected with one end of resistance R10 and the normal phase input end of amplifier U4 respectively；The other end of resistance R10 point
It is not connected with one end of resistance R11 and voltage-regulator diode D3 inputs；Voltage-regulator diode D3 and voltage-regulator diode D4 Opposite direction connections,
Voltage-regulator diode D4 input end groundings；The other end of resistance R11 is connected with the output end of amplifier U4, used as feedforward control module
Output end；The output end of feedforward control module is connected with the I/O ports of microcontroller；The output end and amplifier of yardstick control module
The normal phase input end of U5 is connected.
The beneficial effects of the utility model are：Signal to noise ratio is effectively improved with feedforward controller, device is improved to weak vortex street
The detectability of signal, produces and strengthens accidental resonance effect.The utility model can make the accidental resonance effect of signal stronger
It is strong, make it possible the weak vortex signal of detection more low discharge.This puts down for research accidental resonance provides an excellent experiment
Platform, and for vortex signal detection provides more effective detection method.
Brief description of the drawings
Fig. 1 is the structural representation of vortex signal detection means of the present utility model；
Fig. 2 is the change of scale module circuit diagram of the utility model embodiment；
Fig. 3 is the feedforward control module circuit diagram of the utility model embodiment；
Fig. 4 be the utility model embodiment in flow be 15.85m3/ h (big flow) vortex signal time-domain diagram；
Fig. 5 be the utility model embodiment in flow be 15.85m3/ h (big flow) vortex signal frequency domain figure；
Fig. 6 is not add the classical bistable system power output spectrogram of feed-forward control signals in the utility model embodiment；
Fig. 7 is the classical bistable system power output spectrogram after addition feed-forward control signals in the utility model embodiment.
Specific embodiment
The utility model is described further with reference to the accompanying drawings and examples.
As shown in figure 1, the utility model provides a kind of vortex signal detection means of the accidental resonance with feedforward controller,
Including vortex flow sensors, change of scale module, feedforward control module, microcontroller, output display module and power supply mould
Block；The power module is respectively change of scale module, feedforward control module and microcontroller and provides operating voltage；The whirlpool
Street flow sensor is connected with change of scale module, and the change of scale module is connected with feedforward control module, and the yardstick becomes
Mold changing block, feedforward control module and output display module are connected with microcontroller；The output display module selects TFTLCD
Liquid crystal display.
The microcontroller can be ARM, FPGA and DSP etc., wherein being required to meet, the demand speed of service higher is removed
Carry outside the FLASH of degree of precision ADC and larger capacity individually, be both needed to the additional corresponding module of peripheral hardware；Microcontroller in the present embodiment
Device uses ARMCortex-M4 chips, and it possesses 12 ADC for reaching as high as 2.4M, and is equipped with 168M system clocks and more than 1M
The configuration such as FLASH, implementation of the present utility model can be met.
The power module provides+12V voltage-stabilized power supplies, -12V voltage-stabilized power supplies, 5V voltage-stabilized power supplies and 3.3V voltage-stabilized power supplies,
+ 12V is obtained by 12V power supply adaptors, and -12V power conversion chip LMC7660 with 12V power supply adaptors are obtained, and 5V is by electricity
Source adapter coordinates DC decompression converter MP2359 to obtain, and 3.3V voltage stabilizing chip AMS1117-3.3 with 5V source of stable pressure are obtained
, all it is technological means commonly used in the art wherein realizing the conversion of voltage by each chip, repeat no more here.
As shown in Fig. 2 the change of scale module includes resistance R1, slide rheostat R2, slide rheostat R3, resistance
R4, resistance R5, voltage-regulator diode D1, voltage-regulator diode D2, amplifier U1 and amplifier U2；Wherein ,+12V source of stable pressure respectively with amplifier
The positive supply input of U1 and the positive supply input of amplifier U2 are connected；- 12V source of stable pressure one end, fortune respectively with resistance R1
The negative power end of the negative power end and amplifier U2 of putting U1 is connected；The other end of resistance R1 and coil one end of slide rheostat R2
It is connected, the coil other end of slide rheostat R2 ground connection, the sliding end of slide rheostat R2 and the normal phase input end phase of amplifier U1
Even；The inverting input of amplifier U1 is connected with output end；One end of resistance R4 respectively with coil one end of slide rheostat R3 and
The output end of amplifier U1 is connected, and the sliding end of slide rheostat R3 is connected with the output end of amplifier U2；The other end of resistance R4 and
The inverting input of amplifier U2 is connected；The other end of resistance R5 is connected with the output signal VIN ends of vortex flow sensors, another
End is connected with the normal phase input end of amplifier U2；Voltage-regulator diode D1 and voltage-regulator diode D2 Opposite direction connections, the pole of one voltage stabilizing two
Pipe D2 inputs are connected with 2 output ends of amplifier U, voltage-regulator diode D1 inputs end ground connection；The output end of amplifier U2 is used as chi
The output end of control module is spent, the output end of yardstick control module is connected with an I/O port of microcontroller A/D passages.On
State circuit connection operation principle be：Partial pressure is realized in the series connection of resistance R1 and slide rheostat R2, and sliding slide rheostat R2 can
Change divider resistance value, positive input and the output end of amplifier U1 connect and compose voltage follower, passed through by amplifier U1 after partial pressure
Voltage follower be connected with resistance R4 one end, the resistance R4 other ends connection amplifier U2 reverse input ends, as the reference voltage, electricity
Resistance R5 is balance resistance, improves positive scaling common mode inhibition, and slide rheostat R3 can adjust the gain of amplifying circuit, most
Change of scale is realized eventually, and voltage-regulator diode makes output voltage that the protection to microprocessor is realized no more than 3.3V.
As shown in figure 3, the feedforward control module includes resistance R6, slide rheostat R7, resistance R8, slide rheostat
R9, resistance R10, resistance R11, voltage-regulator diode D3, voltage-regulator diode D4, amplifier U3, amplifier U4 and amplifier U5；Wherein ,+12V
Source of stable pressure respectively with the positive electricity of resistance R6, the positive supply input of amplifier U3, the positive supply input of amplifier U4 and amplifier U5
Source input is connected；- 12V source of stable pressure coil one end respectively with slide rheostat R7, the negative power end of amplifier U3, amplifier U4
The negative power end of negative power end and amplifier U5 is connected；The other end of resistance R6 and the coil other end phase of slide rheostat R7
Even, the sliding end of slide rheostat R7 is connected with the normal phase input end of amplifier U3；The inverting input and output end phase of amplifier U3
Even；One end of resistance R8 is connected with the output end of amplifier U3, and the other end is connected with the inverting input of amplifier U4；Amplifier U5's is anti-
Phase input is connected with output end；One end of resistance R9 is connected with the inverting input of amplifier U5, the other end respectively with resistance R10
One end be connected with the normal phase input end of amplifier U4；The other end of resistance R10 one end respectively with resistance R11 and voltage-regulator diode
D3 inputs are connected；Voltage-regulator diode D3 and voltage-regulator diode D4 Opposite direction connections, voltage-regulator diode D4 input end groundings；Resistance
The other end of R11 is connected with the output end of amplifier U4, used as the output end of feedforward control module；The output end of feedforward control module
It is connected with another I/O port of microcontroller A/D passages；The output end of yardstick control module and the normal phase input end of amplifier U5
It is connected；Foregoing circuit connection operation principle be：The positive input of amplifier U5 connects and composes voltage follower with output end, transports
While putting the voltage follower transmission signal of U5 compositions, suppress influence of the subsequent treatment to preceding circuit, resistance R6 and slip become
Partial pressure is realized in the series connection of resistance device R7, and sliding slide rheostat R7 can change divider resistance value, through the voltage by amplifier U3 after partial pressure
Follower is connected with resistance R8 one end, resistance R8 other ends connection amplifier U4 reverse input ends, influences follow-up hysteresis loop comparator
The connected mode of threshold voltage, slide rheostat R9, resistance R10 and resistance R11 connections constitutes hysteresis loop comparator, by signal two-value
Change is processed, so as to complete feedforward control, obtains class square wave feed-forward signal, and voltage-regulator diode makes output voltage be realized no more than 3.3V
Protection to microprocessor.
Operation principle of the present utility model is as follows：Vortex flow sensors start to gather vortex signal, vortex-street flow sensing
Device is received after signal, is input into change of scale module, and change of scale module is put by voltage follower (amplifier U1), in-phase proportion
Big circuit (amplifier U2) and protection circuit (voltage-regulator diode D1, D2) composition, two slip variable resistances of regulation resistance R2 and resistance R3
Device can make signal concentrate on 0~3.3V, and be read by a passage (PA0) of ARMCortex-M4 chips A/D；Continuation believes this
Number input feedforward control module, feedforward control module is by voltage follower (amplifier U5), with phase hysteresis loop comparator circuit (amplifier
U4), hysteresis loop comparator threshold value return difference control circuit (amplifier U3) and protection circuit (voltage-regulator diode D3, D4) are constituted, and make yardstick
Signal binaryzation after change, obtains class square wave feed-forward signal, and by another passage of ARMCortex-M4 chips A/D
(PA1) read.
After reading signal, yardstick conversion module is calculated using existing noise intensity detection formula by microcontroller and is obtained
Signal, the intensity of signal that feedforward control module is obtained is set by result of calculation, then microcontroller is by before after treatment
The signal that the Signal averaging that feedback control module is obtained is obtained to change of scale module, using showing for being loaded on microcontroller after superposition
The classical bistable system having, finally by display module display output signal frequency domain figure and output signal power spectrogram.According to display
The display result of module adjusts the parameter of feedforward control module, until obtaining that real power spectrum chart can be reflected and right from its
Vortex signal is detected in the power spectrum chart answered.
Embodiment：
It is 15.85m to use new detection flow velocity using this3The flux of vortex street of/h, sets the A/D samplings of ARMCortex-M4
Frequency is fs=5000Hz, the theory characteristic frequency of detection signal is f0 is theoretical=40.40Hz, Fig. 4 and Fig. 5 are respectively and become through yardstick
The time-domain diagram and frequency domain figure of the original vortex signal after mold changing block, have returned the benchmark electricity added in change of scale module herein
Pressure, it can be found that signal is submerged among noise, it is impossible to effectively identification.Existing classical bistable system is loaded on a microcontroller
System, sets the parameter a=1, b=2 of classical bistable system here.This original signal is input into the result obtained after classical bistable system
As shown in Figure 6.Afterwards, the signal that feedforward control module is obtained is acted upon, first returns the benchmark that feedforward control module is added
Voltage, then microcontroller intensity detection is carried out according to original signal, obtain class square-wave signal amplitude C=0.67.Afterwards by class side
Signal after ripple signal compresses as feed-forward control signals and yardstick is together input into classical bistable system, the result for obtaining such as Fig. 7
It is shown.Comparison diagram 6 and Fig. 7 are it can be found that vortex signal frequency f0=40.68Hz (substantially conforms to theoretical value), and accidental resonance
Effect is high to be connect by about one time.It can be seen that, class square-wave signal as feed-forward control signals and classical bistable system combination so that it is random
The detection of resonant weak signal is more accurate.
Claims (5)
1. a kind of vortex signal detection means of the accidental resonance with feedforward controller, it is characterised in that：Passed including flux of vortex street
Sensor, change of scale module, feedforward control module, microcontroller, output display module and power module；The power module
Respectively change of scale module, feedforward control module and microcontroller provide operating voltage；The vortex flow sensors with
Change of scale module is connected, and the change of scale module is connected with feedforward control module, the change of scale module, feedforward control
Module and output display module are connected with microcontroller.
2. the vortex signal detection means of the accidental resonance with feedforward controller according to claim 1, it is characterised in that
The power module provides+12V voltage-stabilized power supplies, -12V voltage-stabilized power supplies, 5V voltage-stabilized power supplies and 3.3V voltage-stabilized power supplies.
3. the vortex signal detection means of the accidental resonance with feedforward controller according to claim 1, it is characterised in that
The output display module selects TFTLCD liquid crystal displays.
4. the vortex signal detection means of the accidental resonance with feedforward controller according to claim 2, it is characterised in that
The change of scale module includes resistance R1, slide rheostat R2, slide rheostat R3, resistance R4, resistance R5, voltage-regulator diode
D1, voltage-regulator diode D2, amplifier U1 and amplifier U2；
Wherein ,+12V source of stable pressure is connected with the positive supply input of amplifier U1 and the positive supply input of amplifier U2 respectively；‐
The negative power end of 12V source of stable pressure one end, the negative power end of amplifier U1 and amplifier U2 respectively with resistance R1 is connected；Resistance R1's
The other end is connected with coil one end of slide rheostat R2, the coil other end ground connection of slide rheostat R2, slide rheostat R2
Sliding end be connected with the normal phase input end of amplifier U1；The inverting input of amplifier U1 is connected with output end；One end of resistance R4
It is connected with coil one end of slide rheostat R3 and the output end of amplifier U1 respectively, the sliding end and amplifier U2 of slide rheostat R3
Output end be connected；The other end of resistance R4 is connected with the inverting input of amplifier U2；The other end and flux of vortex street of resistance R5
The output signal VIN ends of sensor are connected, and the other end is connected with the normal phase input end of amplifier U2；Voltage-regulator diode D1 and voltage stabilizing two
Pole pipe D2 Opposite direction connections, one of voltage-regulator diode D2 inputs are connected with 2 output ends of amplifier U, and voltage-regulator diode D1 is defeated
Enter end to be grounded；The output end of amplifier U2 as yardstick control module output end, the output end and micro-control of yardstick control module
The I/O ports of device processed are connected.
5. the vortex signal detection means of the accidental resonance with feedforward controller according to claim 4, it is characterised in that
The feedforward control module include resistance R6, slide rheostat R7, resistance R8, slide rheostat R9, resistance R10, resistance R11,
Voltage-regulator diode D3, voltage-regulator diode D4, amplifier U3, amplifier U4 and amplifier U5；
Wherein ,+12V source of stable pressure respectively with resistance R6, the positive supply input of amplifier U3, the positive supply input of amplifier U4 and
The positive supply input of amplifier U5 is connected；- 12V source of stable pressure coil one end, the negative electricity of amplifier U3 respectively with slide rheostat R7
The negative power end of source, the negative power end of amplifier U4 and amplifier U5 is connected；The other end of resistance R6 and slide rheostat R7's
The coil other end is connected, and the sliding end of slide rheostat R7 is connected with the normal phase input end of amplifier U3；The anti-phase input of amplifier U3
End is connected with output end；One end of resistance R8 is connected with the output end of amplifier U3, the inverting input phase of the other end and amplifier U4
Even；The inverting input of amplifier U5 is connected with output end；Coil one end of slide rheostat R9 and the inverting input of amplifier U5
It is connected, sliding end is connected with one end of resistance R10 and the normal phase input end of amplifier U4 respectively；The other end of resistance R10 respectively with
One end of resistance R11 is connected with voltage-regulator diode D3 inputs；Voltage-regulator diode D3 and voltage-regulator diode D4 Opposite direction connections, voltage stabilizing
Diode D4 input end groundings；The other end of resistance R11 is connected with the output end of amplifier U4, used as the output of feedforward control module
End；The output end of feedforward control module is connected with the I/O ports of microcontroller；The output end of yardstick control module is with amplifier U5's
Normal phase input end is connected.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106500779A (en) * | 2016-12-27 | 2017-03-15 | 中国计量大学 | The vortex signal detection means of the accidental resonance with feedforward controller |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106500779A (en) * | 2016-12-27 | 2017-03-15 | 中国计量大学 | The vortex signal detection means of the accidental resonance with feedforward controller |
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