CN101696889B - Method of noise removement from flowmeter signal - Google Patents
Method of noise removement from flowmeter signal Download PDFInfo
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- CN101696889B CN101696889B CN2008100993521A CN200810099352A CN101696889B CN 101696889 B CN101696889 B CN 101696889B CN 2008100993521 A CN2008100993521 A CN 2008100993521A CN 200810099352 A CN200810099352 A CN 200810099352A CN 101696889 B CN101696889 B CN 101696889B
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Abstract
The embodiment of the invention discloses a flowmeter filtering system (200) which comprises a noise pass filter (203), a noise counter (204), a damp adjuster (205) and a filter component (206), wherein the noise pass filter (203) is configured to receive a first edition of a flowmeter signal and filter the data of the flowmeter from the flowmeter signal to retain a noise signal; the noise counter (204) is configured to receive the noise signal from the noise pass filter (203) and measure the noise characteristics of the noise signal; the damp adjuster (205) is configured to receive the noise characteristics from the noise counter (204) and generate a damp value based on the noise characteristics; the filter component (206) is configured to receive a second edition of the flowmeter signal and receive the damp value from the damp adjuster (205); and the filter component (206) is further configured to damp the second edition of the flowmeter signal based on the damp value so as to generate a filtering flowmeter signal.
Description
The application's denomination of invention that to be applicant Micro Motion, Inc submit on September 5th, 2003 is divided an application for the Chinese patent application NO.03827035.8's of " flowmeter filtering system and method ".
Technical field
The present invention relates to from flow meter signal, remove the field of denoising, and be particularly related to the periodic noise of from flow meter signal, removing such as crosstalk noise.
Background technology
Flowmeter is used to measure mass velocity, density and the out of Memory of stream material.Described stream material can comprise the solid that suspends in the liquids and gases, liquid of liquid, gas, combination and the liquid of air inclusion and suspended solid.For example, flowmeter is widely used in the well production and the processing of oil and petroleum products.Flowmeter can be used to determine well production by measurement flow rate (promptly by measuring the mass rate through described flowmeter), and even can be used to the gas of definite stream and the relative scale of liquid component.
Produce or processing environment in, make a plurality of flowmeters be connected to identical production line usually and/or a plurality of flowmeters be installed in the mode that the vibration from a flowmeter can arrive another flowmeter.Although this causes measuring effectively flow, described a plurality of flowmeters can interfere with each other with the form of crosstalk noise.Crosstalk is from the influence of the flow meter signal of first flow meter and the phenomenon (vice versa) when destroying flow meter signal from second flowmeter.Crosstalk noise in flowmeter environment normally relatively large, typically be no faster than the slow motion signal of 1 hertz (Hz).Described noise can reduce the degree of accuracy of described flow meter signal, and can cause extremely big indication flow error.In addition, noise can take place because of other factors and other source.
Fig. 1 is the curve map along with the flowmeter output signal that past measured of time.This illustrates the influence how flow meter signal is subjected to other flowmeter.Period 101 and 103 among the figure is illustrated in the flow meter signal that three flowmeters are producing when output, and therefore two flowmeters produce crosstalk noise in the output of present flow rate meter in addition.Period 102 is to have only one else to disturb the flow meter signal of flowmeter when moving.Notice that the noise that is produced all changes on amplitude and frequency in entire curve figure.
Prior art has been attempted by using the traditional filtering technique such as high-pass filtering to handle noise and crosstalk noise.Yet, owing to count less relatively difference on the frequency between the certificate at crosstalk noise and actual flow, and because the low-frequency data signal that flowmeter is exported, so under the situation that does not make the flow meter data variation, be difficult to remove denoising.
Summary of the invention
The present invention helps to solve the problems referred to above of removing denoising from flow meter signal.
A kind of flowmeter filtering system according to embodiments of the invention (200) is provided.Described flowmeter filtering system (200) comprises that noise passes through (pass) wave filter (203), and it is configured to the first version (version) that receives flow meter signal, and leaches described flow meter data with remaining noise signal from described flow meter signal.Described flowmeter filtering system (200) further comprises noise meter measuring device (quantifier) (204), and it is configured to reception from the noise signal of described noise by wave filter (203), and measures the noise characteristic of described noise signal.Described flowmeter filtering system (200) comprises that further damping puts in order device (205), and it is configured to the noise characteristic of reception from described noise meter measuring device (204), and produces damping value based on described noise characteristic.Described flowmeter filtering system (200) further comprises filter element (206), it is configured to second version that receives described flow meter signal and receives damping value from described damping adjuster (205), described filter element (206) is further configured to come second version of the described flow meter signal of damping based on described damping value, so that produce the flow meter signal of filtering.
A kind of method of removing denoising from flow meter signal according to embodiments of the invention is provided.Described method comprises the following steps: to receive described flow meter signal, if described flow meter signal is static basically, then big damping value is applied to described flow meter signal so that produce the flow meter signal of filtering, if and described flow meter signal experiencing a transformation, then little damping value is applied to described flow meter signal so that produce the flow meter signal of filtering.
A kind of method of removing denoising from flow meter signal according to embodiments of the invention is provided.Described method comprises the following steps: to receive described flow meter signal, from the first version of described flow meter signal, leach noise signal basically, measure described noise signal to obtain noise characteristic, determine damping value according to described noise characteristic, described damping value is selected to remove described noise signal basically from described flow meter signal, and use described damping value from second version of described flow meter signal basically damping fall (dampout) described noise so that produce the flow meter signal of filtering.
One aspect of the present invention comprises: before described damping described flow meter signal is normalized to normalized value from original value, and the flow meter signal of the filtering of described damping step is calibrated (scale) basically get back to original flowmeter signal amplitude.
In another aspect of the present invention, described method is determined the error amount between the flow meter signal of second version of described flow meter signal and filtering, and described error amount fed back in the determining of described damping value, wherein said error amount is comprised in the determining of described damping value.
In another aspect of the present invention, described noise comprises digital filter by wave filter and described filter element.
In another aspect of the present invention, described noise comprises infinite-duration impulse response (IIR) digital filter by wave filter and described filter element.
In another aspect of the present invention, described noise comprises the second order iir digital filter by wave filter and described filter element.
In another aspect of the present invention, described damping adjuster is further configured to produce described damping value based on described noise characteristic with based on the damping retardation coefficient.
In another aspect of the present invention, described flow meter signal comprises coriolis flow meter signal.
Description of drawings
Same reference numbers on all figure is represented components identical.
Fig. 1 is the curve map along with the flowmeter output signal that past measured of time;
Fig. 2 is a kind of flowmeter filtering system according to embodiments of the invention;
Fig. 3 illustrates amplitude and the phase response of passing through wave filter according to the noise of one embodiment of the present of invention;
Fig. 4 is the process flow diagram according to the method for denoising of removing from flow meter signal of an alternative embodiment of the invention;
Fig. 5 is the process flow diagram according to the method for denoising of removing from flow meter signal of embodiments of the invention;
Fig. 6 is the curve map that explanation damping from flow meter signal removes denoising;
Fig. 7 is the figure according to the damping adjuster of example of the present invention;
Fig. 8 be can effective various damping values in the flowmeter filtering system of foundation embodiments of the invention curve map; And
Fig. 9 is the curve map that illustrates according to the oblique ascension (ramping) of the described damping value of embodiments of the invention.
Embodiment
How Fig. 2-9 and following declarative description specific examples of the present invention realize and use best mode of the present invention with instruction those skilled in the art.In order to instruct the purpose of principle of the present invention, conventional aspects more of the present invention are simplified or omit.Those skilled in the art will recognize that the variation in the scope of the invention of falling into according to these examples.Those skilled in the art will recognize that following characteristics can be combined in every way to form multiple variation of the present invention.Therefore, the invention is not restricted to following specific examples, but only limit by claims and equivalent thereof.
Flowmeter filtering system-Fig. 2
Fig. 2 is a kind of flowmeter filtering system 200 according to embodiments of the invention.Described flowmeter filtering system 200 receives flow meter signal and leaches noise in described flow meter signal basically from one or more flowmeters.Described flowmeter can comprise the flowmeter of any kind, comprises coriolis flowmeter, turbo flow meter, magnetic flowmeter etc.The described flowmeter filtering system 200 that illustrates in the present embodiment comprises normalization device (normalizer) 201, scaler (scaler) 202, noise by wave filter 203, noise meter measuring device 204, damping adjuster 205 and filter element 206.Should be appreciated that and to expect other flowmeter filtering configuration, and provide shown embodiment in order to illustrate.
Normalization device 201 receives flow meter signal and peak flow values, and has the output that is connected to described filter element 206.Noise also receives flow meter signal (being the first version of described flow meter signal) by wave filter 203, and has the output that is connected to described noise meter measuring device 204.Described noise meter measuring device 204 receives the output of noise by wave filter 203, and has maximum noise output and the zero offset output that is connected to damping adjuster 205.Damping adjuster 205 also receives peak flow values, receives the maximum noise output and the zero offset of output from noise meter measuring device 204, and the error amount that receives output from filter element 206.Damping adjuster 205 has damping value output.Filter element 206 receptions are from the normalization flow meter signal (being second version of described flow meter signal) of normalization device 201 outputs and the damping value of exporting from damping adjuster 205, and the flow meter signal with filtering of falling noise as the error amount and the damping of output.Scaler 202 receives from the flow meter signal of the filtering of filter element 206 outputs, and receives the version of peak flow values, and version calibration, filtering of delivery rate meter signal.
In operation, flow meter signal is imported in the described flowmeter filtering system 200.Described flowmeter filtering system 200 is measured the noise characteristic of described noise, and determines that according to described noise characteristic damping value, described damping value are transfused in the described filter element 206.Described filter element 206 comes the described flow meter signal of damping according to described damping value.Noise such as crosstalk noise has unit rate of flow counting usually according to exporting frequency/response time faster, and therefore dampedly by filter element 206 falls.Therefore, flowmeter filtering system 200 removes denoising not influencing basically or make under the situation of flow meter data variation.
Except the filtering crosstalk noise, flowmeter filtering system 200 can also minimize the external noise from other source, such as the noise that moves or vibrate from physics.For example, positive displacement pump enters in measured the flowing cyclical variation.Sometimes, eliminate this periodic noise so that measure and only report that the average discharge signal is favourable.
Damping is meant the variation that stops signal swing based on frequency.When noise signal when changing than basic flow meter signal faster rate, can use damping to remove de-noised signal.Therefore, damping can be removed the noise signal that is superimposed upon on the flow meter data signal.For example, can from table, select damping value.Described selection can be based on one or more inputs, such as noise amplitude scope (referring to table 1 and following appended argumentation).In the embodiment of digital filter, damping value can be represented filter coefficient.
Yet,, between the tour of flow meter signal, can select less damping value in the adverse effect that takes place to stop when flow velocity changes damping to flow meter signal/make its variation.Transformation is the relatively large of described flow meter data or changes faster.For example, transformation can be adopted flowmeter, the amount of stream material by flowmeter to change at online or off-line to take place when tangible quantity, foam or a pore are present in the liquid flow material or the like.In one embodiment, the response time of flowmeter filtering system 200 was reduced between tour.Therefore, fall described noise with less level damping, until changing process, and flow meter signal becomes static basically (promptly stable) once more.At this moment, damping value can be increased.Therefore, can dynamically control described damping, so that major part or whole noise signals are fallen in damping best according to the present invention.
Based on the peak flow values of input, normalization device 201 changes flow meter signal into normalized flow meter signal.Peak flow values is the upper limit of flow meter signal, and the value that can be determined by calibration process, set according to the type of instrument or the type of stream material etc.Described peak flow values can be a constant, become in the time of perhaps can being with changeable.Use described peak flow values, normalization device 201 is normalized to described flow meter signal input and is not more than described peak flow values.This can be done, so that flowmeter filtering system 200 can be used with flowmeter and any flow signal level of any kind, promptly flowmeter filtering system 200 is irrelevant with the type and the flow condition of flowmeter.In one embodiment, carry out normalization according to following formula:
Scaler 202 is replenishing of normalization device 201.Scaler 202 is from filter element 206 flow meter signals that accept filter, normalized, and the amplitude substantially the same with the flow meter signal of importing got back in its calibration.This finishes by peak flow values is multiply by in the output of filtering.Multiply by peak flow values and be in normalization device 201 to flow meter signal replenishing divided by peak flow values.
Noise receives non-normalized flow meter signal (second version) by wave filter 203, and only makes noise signal pass through (promptly blocking flow meter data).Noise is to determine to be present in the amplitude of any crosstalk noise in the flow meter signal by the purpose of wave filter 203.Described noise can be any wave filter that passes through to the frequency in the scope of about 1Hz at about 0.025 hertz (Hz) that makes basically by wave filter 203, for instance, and such as the device of high pass or bandpass filter.In one embodiment, described noise comprises interchange (AC) coupling filter (being analog filter) by wave filter 203.In another embodiment, described noise comprises infinite-duration impulse response (IIR) digital filter by wave filter 203, comprises the second order iir digital filter.
Described noise preferably has selected the frequency that is higher than 0.025Hz is provided the filter coefficient of unity gain and zero phase by wave filter 203.In one embodiment, described noise has transport function by following expression by wave filter 203:
Transform variable Z wherein
-1Be the output of the front located in the time (t-1), transform variable Z
-2Be the output of the front located in the time (t-2), and numerical value 0.9993,1.9986 etc. is filter coefficient.The transform variable is normally used for expression:
Z＝e
-jω (3)
Should be appreciated that the digital filter coefficient that provides above only is to be provided to the example that is used to illustrate, and the invention is not restricted to given value.Described filter coefficient can change according to the type of wave filter, the quantity that produces the wave filter of noise, flow condition, environmental aspect etc.
Noise is by amplitude and phase curve figure-Fig. 3 of wave filter
Fig. 3 illustrates amplitude and the phase response of passing through wave filter 203 according to the noise of an example of the present invention.In an example shown, frequency value of being normalized to.Because main concern is that noise passes through the response of wave filter 203 at the low side of frequency range, so in the embodiment of digital filter, might improve the performance of noise by the sampling rate of adjusting input signal by wave filter 203.Ideally, noise should not weaken the noise signal component by wave filter 203, and will export the noise component that has amplitude and the zero degrees phase offset of 0dB at the frequency place that is higher than 0.025Hz.For the sampling rate of 20Hz, the output amplitude that records the 0.20Hz noise signal in the real figure filter apparatus is at pact-0.22dB place.For the sampling rate of 5Hz, record described amplitude at pact-0.0141dB place, this is one and significantly improves.Yet the downside of slower sampling rate is the delay of bigger response time.Therefore, described sampling rate be one can be between alignment epoch or the adjustable parameters that is configured during operation.
Refer again to Fig. 2, noise meter measuring device 204 is measured by the noise signal of noise by wave filter 203 outputs, and produces the noise characteristic of described noise signal.In one embodiment, noise meter measuring device 204 is measured the zero offset level (being the skew at the zero point of the equal noise capacity of anomaly (content)) of maximum noise level and described noise signal.Described zero offset/average noise capacity is as the indicator (referring to Fig. 8 and appended argumentation) that whether is stabilized to (being static) state of substantial constant about noise by wave filter 203.
In one embodiment, noise meter measuring device 204 is accumulated in the noise data on the sampling period, and measures the noise characteristic in described sampling period.This can be done, so that characterize noise exactly and prevent that noise from unusually exceedingly influencing described sign.Because the slowest noise signal of expectation is defined as 0.025Hz (it provides 40 seconds wave period) at least, therefore, importantly for the sampling calculating average noise capability value that comprises at least 40 seconds data.
Damping adjuster 205 produces damping values, and described damping value is used to from flow meter signal damping and falls noise.The purpose of described damping adjuster 205 is based on current noise level and present flow rate changes the damping value that comes the described filter element 206 of adaptively modifying.Damping adjuster 205 receive as input from the noise characteristic of noise meter measuring device 204 and peak flow values, together with the error amount that produces by filter element 206.Described error amount comprises about noise how by feedback that fully damping is fallen from the normalization flow meter signal.Whether the damping adjuster divided by peak flow values, basically with zero is center (be damping adjuster 205 determine average noise capacity whether predetermined static threshold value under) so that determine noise signal with zero offset.An embodiment of described damping adjuster 205 at length is discussed below in conjunction with Fig. 7.
In one embodiment, damping adjuster 205 uses the noise signal of input and error amount as the input in the damping value table, and searches suitable damping value.Following table 1 is the example of an embodiment of damping value table.
Table 1
Wherein NC is normalized noise data constant, and it is noise floor (noise floor), and RC is the predetermined ratio constant.Predetermined ratio constant RC is an optional feature, and can involvedly change so that described table is carried out whole ratio.Normalization error amount and look-up table are compared to determine damping value.
In one embodiment, damping adjuster 205 can make damping value ramp to new damping value from current damping value, and not directly carries out the change fully of damping value.Although importantly allow from slowly, it is also important that how fast moving is got back to slow damping value to restriction damping adjuster 205 to the fast transition of fast damping value.If new damping value is than the damping value fast (being that it is less damping value) of front, then new damping value is directly delivered to filter element 206.Yet if new damping value is than the damping value of front slow (being that it is bigger damping value), the damping value of output is ramped up to new damping value (referring to Fig. 7 and appended argumentation) at leisure.
Filter element 206 is configured to the reception damping value, and the normalized flow meter signal of damping.In one embodiment, filter element 206 comprises second order filter.In another embodiment, filter element 206 comprises iir digital filter, comprises the second order iir digital filter.Relative with analog filter, use the advantage of digital filter to be during operation dynamically control figure wave filter.Therefore, can change the quantity of damping so that do not influence the flow meter data signal except that denoising best.In one embodiment, filter element 206 comprises the second order iir digital filter, and it has following transport function:
With
Wherein t is the time-sampling value, U
tBe current input sample, X
tBe according to current input sample U
tValue x with front X
T-1Determine, and Y
tBe defined as according to current input sample U
t, the value X that calculates
tAnd front output valve Y
T-1The output of determining.Digital filter such as above-mentioned digital filter can be implemented in disposal system, for instance, and such as digital signal processor (DSP) equipment.
Flowmeter filtering method-Fig. 4
Fig. 4 is the process flow diagram 400 according to the method for denoising of removing from flow meter signal of embodiments of the invention.In step 401, receive flow meter signal.Described flow meter signal can be comprised the normalization of described flow meter signal by pre-service by any way.
In step 402, if described flow meter signal is static basically, then described method is transferred to step 403; Otherwise described method is transferred to step 404.
In step 403,, big damping value is applied to described flow meter signal because described flow meter signal is static basically.Because described flow meter signal is just changing relatively slowly, do not influence the flow meter data in the described flow meter signal so can use the damping of big quantity, and have only the noise component of described flow meter signal to be weakened by heavy damping.
In step 404, because the value of described flow meter signal is experiencing big or changing fast, so little damping value is applied to described flow meter signal.By this way, the noise component of described flow meter signal is removed basically and does not influence flow meter data.
Flowmeter filtering method-Fig. 5
Fig. 5 is the process flow diagram 500 according to the method for denoising of removing from flow meter signal of an alternative embodiment of the invention.In step 501, receive flow meter signal as previously described.
In step 502, described flow meter data is filtered off from the first version of described flow meter signal basically, so that obtain pure basically noise signal.Can carry out measure in case characterize described noise and from described flow meter signal dynamically damping fall described noise.For example, as previously mentioned, can remove described data by high pass or bandpass filter.
In step 503, measure described noise, thereby and obtain noise characteristic.As previously mentioned, described noise characteristic can comprise maximum noise amplitude and zero offset.Should be appreciated that described noise characteristic is dynamic, and can change in time.For example, when other flowmeter was connected in the production line and therefore produce crosstalk noise, described noise characteristic changed usually.Yet, also can expect other noise source, for instance, such as the neighbourhood noise of coming the self-pumping equipment.
In step 504, determine damping value according to current noise characteristic.Described damping value is represented the quantity of damping, and it will remove described noise basically from described flow meter signal, and will not influence described flow meter signal basically.
In step 505, with described damping value and described flow meter signal input filter element 206, and described filter element 206 uses damping value to come damping to fall described noise.In addition, described damping can ramp to new damping value from current damping value.
Curve map-Fig. 6 of damping
Fig. 6 is the curve map that explanation damping from flow meter signal removes denoising.This curve map comprises flow meter signal 601 and noise signal 602.As can be seen from the figure, when noise signal 602 is damped when falling, described flow meter signal 601 can be approximately square wave.When the step variation appearred in the place in the times 605, the response time of described filtering system changed to response time wave filter very fast.At this time durations, the signal of filtering will be closer similar in appearance to original flow meter signal, is returned to the heavy damping signal until last described filtering system 200.
Damping adjuster-Fig. 7
Fig. 7 is the figure according to the damping adjuster 205 of embodiments of the invention.In this embodiment, damping adjuster 205 comprises absolute value block 701 and 703, product piece 702 and 706, switch block 704 and 710, unit delay piece 705 and 712 (for instance, such as 1/Z unit delay piece), interface 707, damping value piece 708, relational operator piece 709 and damping retardation coefficient piece 711.Described damping adjuster 205 comprises error, maximum noise, peak flow values and zero offset input as previously described, and exports described damping value.
The unit delay that switch block 704 receives maximum noise value, noise figure and produced by unit delay piece 705.If described noise figure is less than the maximum noise value, then switch block 704 is configured to the described noise figure of output, otherwise output maximum noise value.In addition, when not having output noise value or maximum noise value, the switch of switch block 704 exportable fronts output (from unit delay piece 705).The output of switch block 704 is connected to the input of unit delay piece 705, and is connected to product piece 706.
Product piece 706 also receives noise figure and peak flow values.Product piece 70 with peak flow values divided by described noise figure, so that produce the normalized noise figure export interface 707 to.
Interface 707 passes to damping value with normalized error signal and normalized noise signal and searches piece 708.In one embodiment, interface 707 is multiplexed into vector format with normalized noise signal and normalized error signal, and wherein damping value is searched piece 708 and received single input.
Damping value is searched piece 708 and is produced damping value according to the normalized noise input of normalized sum of errors.In one embodiment, in conjunction with the discussion of top Fig. 2, damping value is searched piece 708 execution and is searched to obtain described damping value such as the table of table 1.Damping value is searched piece 708 damping value is exported to relational operator piece 709.
The final stage of damping adjuster 205 (being element 709-712) control damping value can reformed speed.In output place of damping adjuster 205, relational operator piece 709 compares new damping value (searching piece 708 output by damping value) and available current damping value.Relational operator piece 709 produces relation output, and whether described relation output indicates new damping value less than current damping value.
Damping retardation coefficient 711 definition ratio of dampings, and how control damping adjuster 205 can ramp to new damping value fast.In one embodiment, damping retardation coefficient 711 is slightly than a big number.The output of damping retardation coefficient 711 is transfused in the unit delay 712.
Unit delay 712 postpones predetermined delay period of described length of delay.Described predetermined delay period for example can be a constant value, perhaps can obtain from table.The output of unit delay 712 is the damping value output of damping adjuster 205.Therefore, damping adjuster 205 produces damping value based on noise characteristic with based on damping retardation coefficient 711.
Curve map-Fig. 8 of damping value
Fig. 8 be can effective various damping values in the flowmeter filtering system 200 of the foundation embodiment of the invention curve map.This illustrate be used for the different damping value at whole temporal normalized flow velocity.As can be seen, can be not only select damping value so that realize the noise damping of expectation based on the quantity of the damping of expectation but also based on the required period.For example, damping value 1 has faster response than damping value 256.
Curve map-Fig. 9 of damping value oblique ascension
Fig. 9 is the curve that illustrates according to the oblique ascension of the described damping value of example of the present invention.Straight line 900 is damping values of expectation, and curve 901 is damping values of oblique ascension upwards in time.Ramp-up rate can be selected so that on predetermined periods, ramp to the target damping value from starting point.
Advantageously, can from flow meter signal, leach noise, comprise crosstalk noise according to flowmeter filtering of the present invention.Described filtering is to realize under the situation that does not make the flow meter data variation in the flow meter signal.In addition, described filtering adapts to the transformation of data in the flow meter data.
By another advantage provided by the invention is size.Be configured to be used for the common physically big element of needs of analog filter of low frequency.Digital filter apparatus according to some described embodiment is realized better filtering, but utilizes physically less element.In certain embodiments, for example flowmeter filtering system 200 can be implemented in special IC (ASIC).
Relative with analog filter, use another advantage of digital filter to be that digital filter can be controlled dynamically during operation.Can dynamically control described filtering according to noise condition with according to flow condition/level.Therefore, can change the quantity of damping so that do not influence the flow meter data signal except that denoising best.This analog filtering scheme with the filtering of wherein carrying out fixed qty forms contrast.This fixing filters solutions only data-signal and noise signal when being predictable and well-behaved work good.
Claims (9)
1. a method of removing denoising from flow meter signal comprises the following steps:
Receive described flow meter signal;
If described flow meter signal is static basically, then big damping value is applied to described flow meter signal so that produce the flow meter signal of filtering; And
If described flow meter signal is experiencing a transformation, then little damping value is applied to described flow meter signal so that produce the flow meter signal of filtering.
2. the described method of claim 1 further comprises the following steps:
Before described damping step, described flow meter signal is normalized to normalized value from original value; And
The flow meter signal of the filtering of described damping step calibrated basically get back to original flowmeter signal amplitude.
3. the described method of claim 1 further comprises the following steps:
From the first version of described flow meter signal, leach noise signal basically;
Measure described noise signal to obtain noise characteristic; And
Determine damping value according to described noise characteristic, described damping value is selected to remove described noise signal basically and produce the flow meter signal of filtering from described flow meter signal.
4. the described method of claim 1 further comprises the following steps:
From the first version of described flow meter signal, leach noise signal basically;
Measure described noise signal to obtain noise characteristic;
Determine damping value according to described noise characteristic, described damping value is selected to remove described noise signal basically from described flow meter signal;
Determine the error amount between the flow meter signal of second version of described flow meter signal and filtering; And
Described error amount is fed back in the step of determining described damping value, and wherein said error amount is comprised in the determining of described damping value.
5. the described method of claim 1, wherein said noise signal has the frequency in 0.025Hz to 1.0Hz scope.
6. the described method of claim 1, wherein said noise signal comprises periodic noise.
7. the described method of claim 1, wherein said noise signal comprises crosstalk noise.
8. the described method of claim 1, wherein said flow meter signal comprises coriolis flow meter signal.
9. the described method of claim 1 further comprises the following steps:
With the zero offset of described noise characteristic divided by peak flow values to obtain noise figure;
Described noise figure and predetermined static threshold value are compared;
If described noise figure less than described predetermined static threshold value, then uses described noise figure to determine new damping value; And
If described noise figure is not less than described predetermined static threshold value, then use current damping value.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100993521A CN101696889B (en) | 2003-09-05 | 2003-09-05 | Method of noise removement from flowmeter signal |
| HK10106342.0A HK1140255B (en) | 2010-06-29 | Method of removing noise from a flow meter signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100993521A CN101696889B (en) | 2003-09-05 | 2003-09-05 | Method of noise removement from flowmeter signal |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB038270358A Division CN100434869C (en) | 2003-09-05 | 2003-09-05 | Flow meter filtering system and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101696889A CN101696889A (en) | 2010-04-21 |
| CN101696889B true CN101696889B (en) | 2011-08-03 |
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| CN2008100993521A Expired - Lifetime CN101696889B (en) | 2003-09-05 | 2003-09-05 | Method of noise removement from flowmeter signal |
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| CN113959536B (en) * | 2021-10-21 | 2023-11-21 | 宁波水表(集团)股份有限公司 | Denoising method, equipment, medium and product of jet water meter |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5555190A (en) * | 1995-07-12 | 1996-09-10 | Micro Motion, Inc. | Method and apparatus for adaptive line enhancement in Coriolis mass flow meter measurement |
| CN1054199C (en) * | 1992-09-30 | 2000-07-05 | 罗斯蒙德公司 | Vortex flowmeter electronics |
| US6594613B1 (en) * | 1998-12-10 | 2003-07-15 | Rosemount Inc. | Adjustable bandwidth filter for process variable transmitter |
-
2003
- 2003-09-05 CN CN2008100993521A patent/CN101696889B/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1054199C (en) * | 1992-09-30 | 2000-07-05 | 罗斯蒙德公司 | Vortex flowmeter electronics |
| US5555190A (en) * | 1995-07-12 | 1996-09-10 | Micro Motion, Inc. | Method and apparatus for adaptive line enhancement in Coriolis mass flow meter measurement |
| US6594613B1 (en) * | 1998-12-10 | 2003-07-15 | Rosemount Inc. | Adjustable bandwidth filter for process variable transmitter |
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| Publication number | Publication date |
|---|---|
| HK1140255A1 (en) | 2010-10-08 |
| CN101696889A (en) | 2010-04-21 |
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