CN102193082A - Device for positioning leak source of three-sensor multi-scale constrained pipe network - Google Patents

Abstract

The invention provides a device for positioning a leak source of a three-sensor multi-scale constrained pipe network, relates to a device for positioning a leak source of a pipe network, and solves the problem of inaccurate positioning of the leak source of the pipe network. The device comprises three acceleration sensors, three pre-positive amplifiers, three band-pass filters, three postpositive amplifiers, a high speed data collecting card, a result display device, an information storage device and a signal processing device, wherein the three acceleration sensors are arranged at three different measuring points of the pipe network to be measured; output ends of the three acceleration sensors are respectively connected with input ends of the pre-positive amplifiers; the output ends of the three pre-positive amplifiers are respectively connected with the input ends of the corresponding band-pass filters; the output ends of the three band-pass filters are respectively connected with the input ends of the corresponding postpositive amplifiers; the output ends of the three postpositive amplifiers are respectively connected with an input end of the high speed data collecting card; and the output end of the signal processing device is connected with the other input end of the signal storage device. The device is suitable for positioning the leak source of the pipe network.

Description

The device of the multiple dimensioned constraint pipe network of three sensors leak source location

Technical field

The present invention relates to the device of pipe network leak source location.

Background technology

The standard configuration of correlator is: a main frame, two radio transmitters and two high sensitivity acceleration transducers are placed on two sensors on the exposed point of pipeline, general spacing can be controlled in (spacing and caliber, material is relevant) about 100 meters when test.When pipe leakage, can produce the sound wave that leaks at the leak place, and propagate to a distant place along pipeline, when the sound wave that leaks is passed to different sensors, meeting generation time difference Td, as long as the physical length L of pipeline and sound wave are at the velocity of propagation V of this pipeline between given two sensors, the position Lx of leakage point just can calculate by following computing formula: and Lx=(L-V * Td)/2, though seeming, the appearance of correlator can solve the deficiency of leak test plant in the past, but its correctness usually can not satisfy people's requirement, concrete situation about occurring is: 1, more by the peak value that correlator detects, can't judge which is a leak source; 2, the correctness that detects leak source can't be judged, finding after the excavation does not sometimes have leak source, causes the waste of resource and manpower; 3, sometimes owing to circumstance complication, waveform causes having judged whether leak source in a jumble.Existing pipe network leak source location is inaccurate.

Summary of the invention

The objective of the invention is to locate inaccurate problem, the device of the multiple dimensioned constraint pipe network of a kind of three sensors leak source location is provided in order to solve existing pipe network leak source.

The device of the multiple dimensioned constraint pipe network of three sensors leak source location, it comprises three acceleration transducers 1, three prime amplifiers 2, three bandpass filter 3, three post amplifiers 4, high-speed data acquisition card 5, device displaying result 6, information-storing device 7 and signal processing apparatus 8, three acceleration transducers 1 are positioned on three different measuring points will measuring pipe network, the output terminal of three acceleration transducers 1 is connected to the input end of corresponding prime amplifier 2, the output terminal of three prime amplifiers 2 is connected to the input end of corresponding bandpass filter 3, the output terminal of three bandpass filter 3 is connected to the input end of corresponding post amplifier 4, the output terminal of three post amplifiers 4 is connected to an input end of high-speed data acquisition card 5, the output terminal of high-speed data acquisition card 5 is connected an input end of signal storage device 7, an output terminal of signal storage device 7 is connected the input end of device displaying result 6, another output terminal of signal storage device 7 is connected the input end of signal processing apparatus 8, and the output terminal of signal processing apparatus 8 is connected another input end of signal storage device 7.

Characteristics of the present invention are to introduce the 3rd sensor, guarantee the accuracy of positioning result with multiscale analysis, three sensor vectors coupling, end product Verification Technology, because the signal that three sensors obtain can be judged the position of peak value in twos, avoid interference the error that causes, can realize about 200 meters the one-time positioning apart from leak source in the pipeline, the accuracy of the device of the multiple dimensioned constraint pipe network of three sensors leak source location improves 10% at least than prior art.

Description of drawings

Fig. 1 is a structural representation of the present invention, Fig. 2 is a signal processing apparatus process chart of the present invention, Fig. 3 is three road signals of respectively corresponding 3 sensors and spectrogram separately, Fig. 4 is small echo denoising figure, Fig. 5 is the exploded view of four yardsticks of signal, Fig. 6 is multiple dimensioned correlation and the maximizing time corresponding differential intention asked, Fig. 7 is the mistiming summation and the figure that takes absolute value in the corresponding yardstick, Fig. 8 is a minimum value of asking absolute value, the synoptic diagram of the yardstick of search minimum value correspondence, Fig. 9 is for calculating the leak source positioning result, the synoptic diagram of judged result, Figure 10 is the synoptic diagram of result's output, the transducer arrangements figure when Figure 11 surveys for the leak source location, and Figure 12 is A ₁(k) and D ₁(k) obtain coefficient A by reconstruct ₀(k) synoptic diagram, Figure 13 are the wireless signal acquiring schematic representation of apparatus, and Figure 14 is the synoptic diagram of wire signal harvester, and Figure 15 is the synoptic diagram of off-lined signal harvester.

Embodiment

In conjunction with Fig. 1 present embodiment is described, present embodiment comprises three acceleration transducers 1, three prime amplifiers 2, three bandpass filter 3, three post amplifiers 4, high-speed data acquisition card 5, device displaying result 6, information-storing device 7 and signal processing apparatus 8, three acceleration transducers 1 are positioned on three different measuring points will measuring pipe network, the output terminal of three acceleration transducers 1 is connected to the input end of corresponding prime amplifier 2, the output terminal of three prime amplifiers 2 is connected to the input end of corresponding bandpass filter 3, the output terminal of three bandpass filter 3 is connected to the input end of corresponding post amplifier 4, the output terminal of three post amplifiers 4 is connected to three input ends of high-speed data acquisition card 5, the output terminal of high-speed data acquisition card 5 is connected an input end of signal storage device 7, an output terminal of signal storage device 7 is connected the input end of device displaying result 6, another output terminal of signal storage device 7 is connected the input end of signal processing apparatus 8, and the output terminal of signal processing apparatus 8 is connected another input end of signal storage device 7.

The present invention uses comparatively advanced at present acoustics, electronics, software, communication, signal processing apparatus, complex arts such as digitizing are in one, a kind of multiple dimensioned constraint leak source localization method of creationary proposition based on three sensors, change the deficiency of common correlator, have and be simple and easy to use conveniently advantage, and to have than strong anti-interference ability, what want most is the correctness that can judge testing result immediately, flase drop and omission have been avoided, strengthen the adaptive faculty of leak detection and result's accuracy, all advantages that not only have two sensor Leak Noise Correlator commonly used at present, can also realize about 200 meters one-time positioning apart from leak source in the pipeline, time saving and energy saving, low to environment requirement, no matter still can carry out the characteristics of leak source location by day at night, and adaptability is stronger, and estimated result is more sane, still can calculate the result accurately under the helpless situation of two sensors correlator.The more important thing is the correctness of judged result at once, the unnecessary excavation of having avoided flase drop to cause.

The job step of signal processing apparatus 8 is described in conjunction with Fig. 2:

Step 1: reading of data X _i, X _iBe the data that acceleration transducer i gathers, i=1,2,3;

The course of work of reading of data: describe in conjunction with an example, transducer arrangements is seen Figure 11, wherein: L1=102m, L2=15.6m, the simulation leak source is 47m to the distance of sensor 1, is 55m to the distance of sensor 2; 3 sensor acquisition of Pipeline Leakage Point both sides to three road signals: every road sampling rate is 100ks/s, and data length is 32768.Fig. 3 is 1,2,3 road signals and the spectrogram separately (left side among Fig. 3 is a time-domain signal, and the right side among Fig. 3 is corresponding spectrogram) of respectively corresponding 3 sensors;

Step 2: small echo denoising X _i, i=1,2,3; See Fig. 4 (left side is original signal among Fig. 4, and the right side is the signal after the denoising among Fig. 4).

Wavelet transformation: for function or signal f (x) arbitrarily, its wavelet transformation is defined as

$W_f(a,b)={\∫}_{R}f\left(x\right){\stackrel{\‾}{\mathrm{\ψ}}}_{(a,b)}\left(x\right)\mathrm{dx}=\frac{1}{\sqrt{\left|a\right|}}{\∫}_{R}f\left(x\right)\stackrel{\‾}{\mathrm{\ψ}}\left(\frac{x-b}{a}\right)\mathrm{dx}$

Therefore, to function f (x) arbitrarily, its wavelet transformation is a binary function; Because wavelet mother function ψ (x) only just has the fluctuation that obviously departs from transverse axis near initial point, will decay to zero rapidly at local functional value away from initial point, so, for parameter arbitrarily to (a, b), wavelet function ψ _{(a, b)}(x) existence is significantly fluctuateed near x=b, will promptly decay to 0 away from the place of x=b, thereby, from form as can be seen, the wavelet transformation W of function _f(a, what b) numerical value showed is that original function or signal f (x) presses ψ in essence near the x=b point _{(a, b)}What (x) be weighted is average, embodiment be with ψ _{(a, b)}(x) be the situation of change of the f (x) of standard speed, like this, parameter b is represented time centre or the time point analyzed, and parameter a embodiment is to be the size of the environs at center with x=b, so, claim that generally parameter a is a scale parameter, and parameter b is the time centre parameter.Therefore, when the time, Center Parameter b immobilized, wavelet transformation W _f(a, what b) embody is near the situation of change that original function or signal f (x) show when gradually changing along with the scope of analysis and observation x=b point.

Small echo denoising: usually, useful signal is usually expressed as low frequency signal or some signals more stably, noise signal then is usually expressed as high-frequency signal, so noise reduction process mainly carries out following processing: at first original signal is carried out wavelet decomposition, then noise section is generally comprised within the high frequency coefficient; High frequency coefficient to wavelet decomposition carries out quantification treatment with forms such as threshold values then; The last purpose that can reach noise reduction again to signal reconstruction.If a model that contains the one-dimensional signal of noise can be expressed as following form: s (i)=f (i)+σ e (i), i=0,1 ..., n-1. wherein, f (i) is an actual signal, e (i) is a noise, s (i) is for containing the signal of noise.In general, the noise reduction process of one-dimensional signal can be divided into following three steps:

1) wavelet decomposition of one-dimensional signal selects a small echo also to determine the level N of wavelet decomposition, then signal s (i) is carried out N layer wavelet decomposition;

2) threshold value quantizing of wavelet decomposition high frequency coefficient is handled, and selects suitable threshold that each floor height frequency coefficient from 1 to N is carried out quantification treatment;

3) reconstruct of one dimension small echo according to the low frequency coefficient of the N layer of wavelet decomposition with through the high frequency coefficient from 1 to N layer after the quantification treatment, is carried out the reconstruct of one dimension small echo.

The wavelet decomposition of signal and reconfiguration principle: we represent signal on SPACE V and W, i.e. V _j=V _J-1+ W _J-1, that is to say for each at V _jThe signal x (t) of last expression can be used in two SPACE V above-mentioned _J-1And W _J-1In basis function represent:

$x\left(t\right)=\underset{k}{\mathrm{\Σ}}{\mathrm{cA}}_0\left(k\right){\mathrm{\φ}}_{j,k}\left(t\right)$

$=\underset{k}{\mathrm{\Σ}}{\mathrm{cA}}_1\left(k\right){\mathrm{\φ}}_{j-1,k}\left(t\right)+\underset{k}{\mathrm{\Σ}}{\mathrm{cD}}_1\left(k\right)w_{j-1,k}\left(t\right)$

We on yardstick metric space j to coefficient A ₀(k) decompose two coefficient A that obtain at yardstick metric space j-1 ₁(k) and D ₁(k).Same, we also can be from two coefficient A ₁(k) and D ₁(k) obtain coefficient A by reconstruct ₀(k), as the decomposition and reconstruction among Figure 12, we can realize (Wavelet Transformation Algorithm just) by certain bank of filters.When small echo and yardstick are quadrature in the space, we just can calculate coefficient cA with the inner product formula ₁(k) and cD1 (k):

${\mathrm{cA}}_1\left(k\right)=(x\left(t\right),{\mathrm{\φ}}_{j-1,k}\left(t\right))$

$=<\underset{n}{\mathrm{\&Sigma;}}{\mathrm{cA}}_0\left(n\right){\mathrm{\&phi;}}_{j,n}\left(t\right),{\mathrm{\&phi;}}_{j-1,k}\left(t\right)>$

$=\underset{n}{\mathrm{\&Sigma;}}{\mathrm{cA}}_0\left(n\right)<{\mathrm{\&phi;}}_{j,n}\left(t\right),{\mathrm{\&phi;}}_{j-1,k}\left(t\right)>$

Be the concrete formula of inner product computing method below:

$({\mathrm{\&phi;}}_{j,n}\left(t\right),{\mathrm{\&phi;}}_{j-1,k}\left(t\right))={\&Integral;}_{-\&infin;}^{\&infin;}\sqrt{2^j}\mathrm{\&phi;}(2^j-n)\sqrt{2^{j-1}}\mathrm{\&phi;}(2^{j-1}t-k)\mathrm{dt}$

$={\&Integral;}_{-\&infin;}^{\&infin;}\sqrt{2^{2j-1}}\mathrm{\&phi;}(2^j-n)\mathrm{\&phi;}(2^{j-1}t-k)\mathrm{dt}(\mathrm{substitutes}=2^{j-1}-k)$

$={\&Integral;}_{-\&infin;}^{\&infin;}\sqrt{2}\mathrm{\&phi;}(2s+2k-n)\mathrm{\&phi;}\left(s\right)\mathrm{ds}(\mathrm{Use\; the}2-\mathrm{scale\; equation\; for\&phi;}\left(s\right))$

$={\&Integral;}_{-\&infin;}^{\&infin;}\sqrt{2}\mathrm{\&phi;}(2s+2k-n)\underset{m}{\mathrm{\&Sigma;}}{h}_0\left(m\right)\sqrt{2}\mathrm{\&phi;}(2s-m)\mathrm{ds}$

$=\underset{m}{\mathrm{\&Sigma;}}{h}_0\left(m\right){\&Integral;}_{-\&infin;}^{\&infin;}\mathrm{\&phi;}(2s+2k-n)\mathrm{\&phi;}(2s-m)2\mathrm{ds}(\mathrm{integral\; is}0\mathrm{unless\; m}=n-2k)$

$=h_0(n-2k)$

Concrete coefficient calculations process is as follows:

${\mathrm{cA}}_1\left(k\right)=\underset{n}{\mathrm{\&Sigma;}}{h}_0(n-2k){\mathrm{cA}}_0\left(n\right)$

${\mathrm{cD}}_1\left(k\right)=<x\left(t\right),w_{j-1,k}\left(t\right)>$

$=<\underset{n}{\mathrm{\&Sigma;}}{\mathrm{cA}}_0\left(n\right){\mathrm{\&phi;}}_{j,n}\left(t\right),w_{j-1,k}\left(t\right)>$

$=\underset{n}{\mathrm{\&Sigma;}}{\mathrm{cA}}_0\left(n\right)<{\mathrm{\&phi;}}_{j,n}\left(t\right),w_{j-1,k}\left(t\right)>$

${\mathrm{cD}}_1\left(k\right)=\underset{n}{\mathrm{\&Sigma;}}{h}_1(n-2k)c{A}_0\left(n\right)$

For top wavelet decomposition process, the coefficient by designing Hi-pass filter and two groups of wave filters of low-pass filter respectively (array g[] and h[]) can realize.

Step 3: multiple dimensioned decomposition X _Ij, i=1,2,3, j=1,2 ... n; See Fig. 5 (, only having shown exploded view among Fig. 5) to four yardsticks of signal because map sheet is limited.

The ground floor that can simply be described as the multi-scale wavelet decomposition is that signal x is resolved into low frequency A ₁With high frequency D ₁Two parts, low frequency A ₁In what comprise is the profile information of signal x, high frequency D ₁The detailed information that comprises signal x; In the decomposition of following one deck, again with A ₁Resolve into low frequency A ₂With high frequency D ₂Two parts, low frequency A ₂That comprise is signal A ₁Profile information, high frequency D ₂That comprise is signal A ₁Detailed information; So analogize down, can carry out deeper decomposition.

Step 4: corresponding each yardstick is asked correlation;

Cross correlation function:

x ₁(t), x ₂(t) be two different functions, in information acquisition, just refer to two different signals.Can be with the time history sample x in the sufficiently long timing statistics T for the related function of steady traversal random signal classics ₁(t), x ₂(t) time average of product calculates promptly:

T in the formula is time or displacement.

Step 5: maximizing correlation time corresponding is poor; See Fig. 6 (shown 13 yardsticks among Fig. 6, between the sensor 1,2, between the sensor 2,3, the maximum related value time corresponding between the sensor 3,1 is poor).

Mistiming: the mistiming is by related function

Calculate, the time " τ " of the maximal value corresponding position that calculates is the mistiming.

Step 6: the mistiming sues for peace and takes absolute value in the corresponding yardstick; The mistiming of sensor 1,2: the time that refers to leak source voice signal arrival sensor 1 deducts the time that arrives sensor 2; The mistiming of same sensor 2,3: the time that refers to leak source voice signal arrival sensor 2 deducts the time that arrives sensor 3; The mistiming of sensor 3,1: the time that refers to leak source voice signal arrival sensor 3 deducts the time that arrives sensor 1, and the summation of the mistiming in each yardstick in the step 5 (Fig. 6) is also taken absolute value, and Fig. 7 has provided result calculated.

Step 7: the minimum value of asking absolute value; Find out the minimum value in the step 6 result of calculation (Fig. 7), the result as shown in Figure 8, minimum value is 0 in this example.

Step 8: the yardstick of search minimum value correspondence; Embodied a very important constraint rule at this, i.e. " three sensor vectors coupling rule ".

Three microphone vector matching relations are as follows:

Any two passage i, j (i, j=1,2,3 ...), the time delay of two passages is: τ _Ij=τ _i-τ _j

And have:: τ _Ji=τ _j-τ _i=-τ _Ij

If order has a passage k, then have: τ _Ij=τ _i-τ _j+ τ _k-τ _k=(τ _i-τ _k)-(τ _j-τ _k)=τ _Ik-τ _Jk

τ in sum _Ij+ τ _Jk+ τ _Ki=τ _Ik-τ _Jk+ τ _Jk+ τ _Ki=τ _Ik+ τ _Ki=0

Following formula is three microphone vector matching rules, as the vector triangle summation, is at last " 0 ".It is applicable to the time delay between any three microphones, as seen, for the signal of normal propagation, satisfies this relation beyond doubt, and opposite, the possibility that noise contribution satisfies this relation is then very little.So, for the estimated result that obtains according to each yardstick under low, the high resolving power, can carry out the examination of optimal result according to its matching degree (being matching error), i.e. absolute value and the more little three sensor vector matching relationships that meet more to three microphone vector matching relations.By the index of minimum value correspondence, find corresponding yardstick, this yardstick is the yardstick that calculates as the result.By Fig. 8 result displayed as can be known between the sensor 1,2 mistiming of received signal be-0.005s, the mistiming of received signal is-0.0106s between the sensor 2,3, the mistiming of received signal is 0.0156s between the sensor 3,1.

Step 9: calculate the leak source positioning result; Before calculating, to import the starting condition of location: the distance L 1 between assessment distance and the sensor 1,2.As shown in Figure 9, input " assessment distance " is the actual range L2=15.6m between the sensor 2,3 among Figure 11, is to be used for computing velocity, and is used for the judgement of net result accuracy.Input " distance between the sensor 1,2 " L1 is used for final location.

Known L2=15.6m, i.e. distance between the sensor 2,3; Mistiming between the sensor 2,3 is-0.0106s that promptly voice signal passes to sensor 2, is from leak source: v=15.6/0.0106=1471.7m/s in the velocity of propagation of this pipeline than passing to sensor 3 leading 0.0106s, can calculating sound thus; Mistiming between the sensor 1,2 is-0.005s, and promptly the voice signal of leak source passes to sensor 1 than the time lead 0.005s that passes to sensor 2, and establishing leak source is D1 to the distance of sensor 1, is D2 to the distance of sensor 2;

Then: $\left\{\begin{array}{c}D1+D2=L1\\ D1-D2=\mathrm{V\&tau;}\end{array}\right.$

So, $D1=\frac{L1+\mathrm{V\&tau;}}{2}=\frac{102+1471.7\&times;(-0.005)}{2}=47.32m,$ D2＝L1-D1＝54.68m。

Step 10: judged result; Though because three sensor vector matching relationships have been satisfied in the adding of the 3rd sensor, on algorithm, realized multiple dimensioned optimum delay estimation, but because on-the-spot complicacy, and the random failure of instrument etc. still has the generation of inaccurate phenomenon unavoidably, also just because the adding of the 3rd sensor makes the result who calculates that physical verification arranged, because three any two distances of sensor are known, the time delay that leak source arrives 2 of homonymies is known, and the distribution of three sensors always has two sensors and is distributed in homonymy.So just can be used in the mistiming of two sensors of homonymy checks final system and has calculated result's accuracy.

In step 9, use the assessment distance of input, just can calculate velocity of propagation v=1471.7m/s with the heavy surplus mistiming of two sensors of homonymy, judge this speed according to practical experience in cast-iron pipe acoustic signal propagation velocity range at this, so can determine that the result is credible.The error of calculation is:

Step 11: the result shows, sees the net result of Figure 10.

In sum, the characteristics of this method maximum are exactly the introducing of the 3rd sensor, guarantee three gordian techniquies of accuracy as a result: 1. multiscale analysis; 2. three sensor vectors mate; 3. end product is checked.

Specific embodiment one

In conjunction with Figure 13 present embodiment is described, three acceleration transducers 1 of present embodiment, three prime amplifiers 2, three bandpass filter 3, three post amplifiers 4, signal storage device 7, signal processing apparatus 8 and device displaying results 6 all in the short period of time real-time continuous carry out, owing to increased wireless transmit and receiver module, acceleration transducer 1 is communicated with prime amplifier 2 by wireless telecommunications, has so just significantly reduced longly need draw the inconvenience of establishing very long data line during apart from testing and bother.

Specific embodiment two

In conjunction with Figure 14 present embodiment is described, three acceleration transducers 1 of present embodiment, three prime amplifiers 2, three bandpass filter 3, three post amplifiers 4, signal storage device 7, signal processing apparatus 8 and device displaying results 6 all in the short period of time real-time continuous carry out, though need draw during the present embodiment testing and establish data line, acceleration transducer 1 is communicated with prime amplifier 2 by data line, but investment and the signal of having saved wireless acquisition module are more reliable relatively.

Specific embodiment three

In conjunction with Figure 15 present embodiment is described, present embodiment adopts off-lined signal harvester processing mode, specific implementation method is: at first all acquisition modules all will be set on portable computer, comprise zero-time, sampling length, sample frequency and enlargement factor etc., when promptly all acquisition modules being put into tested point, the same time begins, be stored in each module behind the signal according to same frequency acquisition and the same length of enlargement factor collection, wait completely to download to after collecting all modules together and carry out analyzing and processing on the portable computer and provide the result.Comprise in the off-line acquisition module: acceleration transducer 1, prime amplifier 2, bandpass filter 3, post amplifier 4, signal memory cell, control module and power supply unit etc., portable computer is equipped with the signal processing apparatus program, can carry out data processing to the data that any three acquisition modules get.The collection of this mode signal and final computing are not carried out in real time, can reduce the equipment of on-the-spot testing, can increase acquisition module easily simultaneously yet, can carry out large-area pipe network leak source generaI investigation.

Claims (1)

1. the device of the multiple dimensioned constraint pipe network of three sensors leak source location, it is characterized in that it comprises three acceleration transducers (1), three prime amplifiers (2), three bandpass filter (3), three post amplifiers (4), high-speed data acquisition card (5), device displaying result (6), information-storing device (7) and signal processing apparatus (8), three acceleration transducers (1) are positioned on three different measuring points will measuring pipe network, the output terminal of three acceleration transducers (1) is connected to the input end of corresponding prime amplifier (2), the output terminal of three prime amplifiers (2) is connected to the input end of corresponding bandpass filter (3), the output terminal of three bandpass filter (3) is connected to the input end of corresponding post amplifier (4), the output terminal of three post amplifiers (4) is connected to an input end of high-speed data acquisition card (5), the output terminal of high-speed data acquisition card (5) is connected an input end of signal storage device (7), an output terminal of signal storage device (7) is connected the input end of device displaying result (6), another output terminal of signal storage device (7) is connected the input end of signal processing apparatus (8), and the output terminal of signal processing apparatus (8) is connected another input end of signal storage device (7).

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