CN104376881B - Based on Hilbert transform and the positioning method for loosening member of nuclear power station of data screening - Google Patents

Abstract

Based on Hilbert transform and the positioning method for loosening member of nuclear power station of data screening, it is being knocked grid division on thing；Acceleration transducer is installed；Calculate each grid element center point range difference to acceleration transducer two-by-two；Gather the shock signal that each acceleration transducer receives；Use moving average method to eliminate the low-frequency noise of signal, use Butterworth wave filter to be filtered by environmental background noise；Impact signal after de-noising is carried out Hilbert transform, obtains the oscillation starting points moment of impact signal；The difference time of advent between the poor and each passage of propagation distance according to grid element center point to each sensor calculates the nominal spread speed of each grid element center point；The nominal spread speed of all grid element center points is carried out data screening, calculates its variance；Look for minima in all variances, and record the coordinate of its central point, positioning result is shown.It is high that the present invention has positioning precision, the advantage that search speed is fast.

Description

Based on Hilbert transform and the positioning method for loosening member of nuclear power station of data screening

Technical field

The present invention relates to nuclear power station technical field, be specifically related to nuclear power station based on Hilbert transform and data screening pine Moving part localization method.

Technical background

Nuclear power station exists the connectors such as substantial amounts of screw, nut, due to the continuous impact of high-velocity flow, burn into occurs Depreciation and loosen even fall, also have system test, refuel, the overhaul stage from the external world enter system metal fragment, This all can make stability that system runs and reliability reduce, and even has influence on the safety of whole nuclear power station.Loosening element positions As the important component part of loose parts monitoring system, location loosening element is conducive to being quickly found out pine when Shutdown exactly Moving part, and repair accordingly, reduce maintainer as far as possible and be exposed to the time under radioprotective, it is ensured that the peace of maintainer Entirely, stability and safety for nuclear power station are very helpful.

Existing loosening element location pertinent literature has:

G..Por, J.Kiss, I.Sorosanszky, G..Szappanos, Development of a false alarm Free advanced loose parts monitoring system (ALPS) [J], Progress in Nuclear Energy, 2003,43 (1-4): 243-251. mono-kind based on signal SPRT (Sequence Probability Ratio Test, SPR sequential probability ratio is tested) time difference estimation method, first signal carried out albefaction, then by calculating albefaction with the AR model of noise The SPRT of signal carrys out estimating signal step-out time.

Yong Beum Kim,Seon Jae Kim,Hae Dong Chung,Yong Won Park,Jin Ho Park,A Study on Technique to Estimate Impact Location of Loose Part Using Wigner- Ville Distribution [J], Progress in Nuclear Energy, 2003,43 (1-4): 261-266. mono-kind bases Study on estimation method in the loosening element impact position of Wigner-Willie distribution, it is proposed that signal is carried out Wigner-Willie and becomes Change, obtain time-frequency figure, and then obtain loosening element falls position.The method accuracy is high, but amount of calculation is the biggest.Each signal time Frequency domain line is all different, and needs manual drafting, is unfavorable for realizing automatization.

S.Figedy,G..Oksa,Modern methods of signal processing in the loose Part monitoring system [J], Progress in Nuclear Energy, 2005,46 (3-4): 253-267. mono- Plant time difference estimation method based on Wavelet Denoising Method, by Wavelet Denoising Method, i.e. remove effect of noise, estimate the time difference the most again.Should Method, owing to eliminating effect of noise, preferably estimates effect so still having in the case of low signal-to-noise ratio, but due to The method still using the zero crossing of signal as time of arrival (toa), does not accounts for the complicated communication mode of bending wave, so During actual location when propagation distance farther out time yet suffer from bigger error.

Seong-Nam Jeong,Kyoung-Hang Woo,Eoun-Taeg Hwang,Won-HoChoi,A Study on the Estimation Method of Impact Position Using the Frequency Analysis[J], Strategic Technology.The 1st International Forum on, 2006:392-395. mono-kind is based on frequency The impact position Study on estimation method analyzed, it is proposed that a kind of method for positioning loosening element based on frequency dispersion.The method accuracy is high, Stability is the highest, but early stage needs to set up fairly perfect data base, and workload is big.

Summary of the invention

In order to achieve the above object, the technical scheme that the present invention takes is:

Based on Hilbert transform and the positioning method for loosening member of nuclear power station of data screening, comprise the following steps:

1) according to positioning accuracy request, it is being knocked grid division on thing, then to ready-portioned grid numbering 1～N；

2) it is being knocked on thing by equilateral triangle layout 3 acceleration transducers of installation, during to obtain loosening element falls Shock signal f (t) produced；

3) according to the distance of the geometry computations each grid element center point to each acceleration transducer two-by-two being knocked thing Difference d_i,j；

4) shock signal f (t) received by each acceleration transducer of data collecting card synchronous acquisition, clashes into signal Impact signal s (t) when f (t) includes loosening element falls and environmental background noise n (t)；

5) use moving average method to eliminate the low-frequency noise clashing into signal f (t), then use 8 rank Butterworth wave filter Environmental background noise n (t) is filtered, impact signal s (t) of the noise jamming that has been eliminated；

6) to step 5) in process impact signal s (t) that obtains and be analyzed with Hilbert transform, obtain impact signal The oscillation starting points moment of s (t)；Owing to the moment that impact signal s (t) falls cannot be known, can only rushing from 3 acceleration transducers Hitting and obtain the time difference that ripple is propagated in signal s (t), the difference time of advent between each two passage is t_i,j；

7) according to propagation distance difference d of grid element center point to each acceleration transducer_i,jAnd the time of advent between each passage Difference t_i,jCalculate nominal spread speed v of each grid element center point_i,j；

8) speed bound v that bending wave is propagated in the structure is calculated_maxAnd v_min；

9) nominal spread speed v to all grid element center points_i,jCarry out data screening: judge name spread speed v_i,jIt is No speed interval [the v propagated at bending wave_max,v_minIn], if nominal spread speed v of grid element center point_i,jAll at speed interval [v_max,v_minIn], then calculate variance D (v) of the speed of this grid element center point, be assigned to a big value otherwise to variance D (v)；

10) search for minima in variance D (v) of all grid element center point, record the coordinate of its central point；

11) positioning result shows.

Described step 3) in, for plane, according to formula (1) calculate grid element center to each acceleration transducer away from Deviation:

$d_{i,j}=\sqrt{{(x-x_i)}^2+{(y-y_i)}^2}-\sqrt{{(x-x_j)}^2+{(y-y_i)}^2}---\left(1\right)$

Wherein (x y) is the coordinate of grid element center point, (x_i,y_i) it is the coordinate of acceleration transducer i, (x_j,y_j) for accelerating The coordinate of degree sensor j, i=1,2,3；J=1,2,3；i≠j；

For hemisphere face, according to the range difference of formula (2) calculating grid element center to each acceleration transducer:

Wherein r is the radius of ball,For the spherical coordinates of grid element center point,Ball for acceleration transducer i is sat Mark,For the spherical coordinates of acceleration transducer j, i=1,2,3；J=1,2,3；i≠j.

Described step 5) in, eliminate according to formula (3) and clash into signal f (t) low-frequency noise:

$f^{\′}\left(t\right)=\frac{(f\left(t\right)+f(t-1)+...f(t-n+1))}{n}---\left(3\right)$

Wherein f'(t) it is the shock signal after rolling average, n is the number in period of rolling average, and n is set to 7.

Described step 6) in, determine impact signal s (t) the oscillation starting points moment according to the peak value of envelope, specifically include Following steps:

6.1) Hilbert transform of impact signal s (t) is askedAccording to definition:

$\hat{s}\left(t\right)={\∫}_{-\∞}^{\∞}s\left(t\right)\frac{1}{\mathrm{\π}(t-\mathrm{\τ})}\mathrm{d\τ}---\left(4\right)$

Wherein,Hubert transformed signal for impact signal s (t)；

6.2) with impact signal s (t) as real part, its hubert transformed signalFor imaginary part, constitute a new function Such as formula (5):

$z\left(t\right)=s\left(t\right)+j\hat{s}\left(t\right)=\left|z\left(t\right)\right|\exp \left(\mathrm{j\θ}\left(t\right)\right)---\left(5\right)$

Wherein,Being the magnitude function of new function, θ (t) is phase function, and | z (t) | is then The envelope function of impact signal s (t)；

6.3) | z (t) | the peaking to magnitude function: the relatively amplitude of 6 points that each point is adjacent, if this point is for amplitude Big value, then the peak value that the amplitude of this point is, taking the time point t corresponding to first peak value tried to achieve is impact signal s (t) The starting of oscillation moment, calculate the time difference between each acceleration transducer according to formula (6):

t_i,j=t_i-t_j (6)

Wherein, t_iFor the starting of oscillation moment of acceleration transducer i, t_jFor the starting of oscillation moment of acceleration transducer j, i=1,2,3； J=1,2,3；i≠j.

Described step 7) in, calculate name spread speed v according to formula (7)_i,j:

$v_{i,j}=\frac{d_{i,j}}{t_{i,j}}---\left(7\right)$

Wherein, d_i,jFor the range difference of grid element center point to each acceleration transducer two-by-two, t_i,jIt is between two passages The time of advent is poor, i=1,2,3；J=1,2,3；i≠j.

Described step 8) in, calculate bending wave speed bound v according to (8) formula_maxAnd v_min:

$\begin{array}{c}{v}_{\max }=2{{\mathrm{\ω}}_{\max }}^{\frac{1}{2}}{\left(\frac{{\mathrm{Eh}}^3}{12\mathrm{\ρ}(1-{\mathrm{\υ}}^2)}\right)}^{\frac{1}{4}}\\ v_{\min }=2{{\mathrm{\ω}}_{\min }}^{\frac{1}{2}}{\left(\frac{{\mathrm{Eh}}^3}{12\mathrm{\ρ}(1-{\mathrm{\υ}}^2)}\right)}^{\frac{1}{4}}\end{array}---\left(8\right)$

Wherein ω_max, ω_minBeing respectively the highest angular frequency of bending wave and minimum angular frequency, E is the Young's modulus of material, h For being knocked the thickness of object, ρ is the density of material, and υ is the Poisson's ratio of material.

The present invention need not demarcate the spread speed of bending wave in advance, it is to avoid the error that rate calibration introduces.Velocity interval can Calculate with the material parameter and structural parameters by being knocked thing, it is also possible to be adjusted determining by experiment.The present invention By limiting velocity interval, only retain the valid data of rum point near zone, reduce hunting zone, considerably reduce meter Calculation amount, reduces the estimation precision impact on result of time difference and range difference simultaneously.It is high that the present invention has positioning precision, searches Fireballing advantage.

Accompanying drawing explanation

Fig. 1 is the method flow block diagram of the present invention.

Fig. 2 is embodiment impact signal Hilbert envelope figure.

Fig. 3 is embodiment positioning result display figure.

Fig. 4 is embodiment loosening element alignment system overall framework figure.

Fig. 5 is embodiment acceleration transducer layout.

Detailed description of the invention

Below in conjunction with the accompanying drawings the present invention is described in detail.

As it is shown in figure 1, nuclear power station loose positioning parts method based on Hilbert transform and data screening, including following Step:

1) according to positioning accuracy request, it is being knocked grid division on thing, then to ready-portioned grid numbering 1～N；

2) it is being knocked on thing by equilateral triangle layout 3 acceleration transducers of installation, during to obtain loosening element falls Shock signal f (t) produced；

3) according to the distance of the geometry computations each grid element center point to each acceleration transducer two-by-two being knocked thing Difference d_i,j；

4) shock signal f (t) received by each acceleration transducer of data collecting card synchronous acquisition, clashes into signal Impact signal s (t) when f (t) includes loosening element falls and environmental background noise n (t)；

5) use moving average method to eliminate the low-frequency noise clashing into signal f (t), then use 8 rank Butterworth wave filter Environmental background noise n (t) is filtered, impact signal s (t) of the noise jamming that has been eliminated；

6) to step 5) in process impact signal s (t) that obtains and be analyzed with Hilbert transform, obtain impact signal The oscillation starting points moment of s (t)；Owing to the moment that impact signal s (t) falls cannot be known, can only rushing from 3 acceleration transducers Hitting and obtain the time difference that ripple is propagated in signal s (t), the difference time of advent between each two passage is t_i,j；

7) according to propagation distance difference d of grid element center point to each acceleration transducer_i,jAnd the time of advent between each passage Difference t_i,jCalculate nominal spread speed v of each grid element center point_i,j；

8) speed bound v that bending wave is propagated in the structure is calculated_maxAnd v_min；

9) nominal spread speed v to all grid element center points_i,jCarry out data screening: judge name spread speed v_i,jIt is No speed interval [the v propagated at bending wave_max,v_minIn], if nominal spread speed v of grid element center point_i,jAll at speed interval [v_max,v_minIn], then calculate variance D (v) of the speed of this grid element center point, be assigned to a big value otherwise to variance D (v)；

10) search for minima in variance D (v) of all grid element center point, record the coordinate of its central point；

11) positioning result shows.

Described step 3) in, for plane, according to formula (1) calculate grid element center to each acceleration transducer away from Deviation:

$d_{i,j}=\sqrt{{(x-x_i)}^2+{(y-y_i)}^2}-\sqrt{{(x-x_j)}^2+{(y-y_i)}^2}---\left(1\right)$

Wherein (x y) is the coordinate of grid element center point, (x_i,y_i) it is the coordinate of acceleration transducer i, (x_j,y_j) for accelerating The coordinate of degree sensor j, i=1,2,3；J=1,2,3；i≠j；

For hemisphere face, according to the range difference of formula (2) calculating grid element center to each acceleration transducer:

Wherein r is the radius of ball,For the spherical coordinates of grid element center point,Ball for acceleration transducer i is sat Mark,For the spherical coordinates of acceleration transducer j, i=1,2,3；J=1,2,3；i≠j.

Described step 5) in, eliminate according to formula (3) and clash into signal f (t) low-frequency noise:

$f^{\′}\left(t\right)=\frac{(f\left(t\right)+f(t-1)+...f(t-n+1))}{n}---\left(3\right)$

Wherein f'(t) it is the shock signal after rolling average, n is the number in period of rolling average, and n is set to 7.

Described step 6) in, determine impact signal s (t) the oscillation starting points moment according to the peak value of envelope, specifically include Following steps:

6.1) Hilbert transform of impact signal s (t) is askedAccording to definition:

$\hat{s}\left(t\right)={\∫}_{-\∞}^{\∞}s\left(t\right)\frac{1}{\mathrm{\π}(t-\mathrm{\τ})}\mathrm{d\τ}---\left(4\right)$

Wherein,Hubert transformed signal for impact signal s (t)；

6.2) with impact signal s (t) as real part, its hubert transformed signalFor imaginary part, constitute a new function Such as formula (5):

$z\left(t\right)=s\left(t\right)+j\hat{s}\left(t\right)=\left|z\left(t\right)\right|\exp \left(\mathrm{j\θ}\left(t\right)\right)---\left(5\right)$

Wherein,Being the magnitude function of new function, θ (t) is phase function, and | z (t) | is then The envelope function of impact signal s (t)；

6.3) | z (t) | the peaking to magnitude function: the relatively amplitude of 6 points that each point is adjacent, if this point is for amplitude Big value, then the peak value that the amplitude of this point is, taking the time point t corresponding to first peak value tried to achieve is impact signal s (t) The starting of oscillation moment, calculate the time difference between each acceleration transducer according to formula (6):

t_i,j=t_i-t_j (6)

Wherein, t_iFor the starting of oscillation moment of acceleration transducer i, t_jFor the starting of oscillation moment of acceleration transducer j, i=1,2,3； J=1,2,3；i≠j.

Described step 7) in, calculate name spread speed v according to formula (7)_i,j:

$v_{i,j}=\frac{d_{i,j}}{t_{i,j}}---\left(7\right)$

Wherein, d_i,jFor the range difference of grid element center point to each acceleration transducer two-by-two, t_i,jIt is between two passages The time of advent is poor, i=1,2,3；J=1,2,3；i≠j.

Described step 8) in, calculate bending wave speed bound v according to (8) formula_maxAnd v_min:

$\begin{array}{c}{v}_{\max }=2{{\mathrm{\ω}}_{\max }}^{\frac{1}{2}}{\left(\frac{{\mathrm{Eh}}^3}{12\mathrm{\ρ}(1-{\mathrm{\υ}}^2)}\right)}^{\frac{1}{4}}\\ v_{\min }=2{{\mathrm{\ω}}_{\min }}^{\frac{1}{2}}{\left(\frac{{\mathrm{Eh}}^3}{12\mathrm{\ρ}(1-{\mathrm{\υ}}^2)}\right)}^{\frac{1}{4}}\end{array}---\left(8\right)$

Wherein ω_max, ω_minBeing respectively the highest angular frequency of bending wave and minimum angular frequency, E is the Young's modulus of material, h For being knocked the thickness of object, ρ is the density of material, and υ is the Poisson's ratio of material.

Below in conjunction with embodiment, the present invention is described in detail.

As a example by the flat board installing three acceleration transducers by equilateral triangle, illustrate to use Scan orientation method energy accurately Estimate the falling position of loosening element.If the coordinate of certain arbitrfary point Q is that (x, y), acceleration transducer i coordinate is (x to Q on steel plate_i, y_i), acceleration transducer j coordinate is (x_j,y_j), then arbitrfary point Q between acceleration transducer i and acceleration transducer j away from Deviation is $d_{i,j}=\sqrt{{(x-x_i)}^2+{(y-y_i)}^2}-\sqrt{{(x-x_j)}^2+{(y-y_i)}^2}$ (i=1,2,3；J=1,2,3；i≠j).

Gather and clash into signal f (t), obtain impact signal s (t) after de-noising, and impact signal s (t) is carried out Hilbert Conversion, each passage is asked for as shown in Figure 2 the time of advent.

Assume that impact signal s (t) produced travels to the time difference of 3 acceleration transducers and is respectively t_1,2、t_1,3、t_2,3, So name spread speed

Data screening first pass through hit the highest low-limit frequency of the structural parameters of thing, material parameter and impact signal can Calculate bending wave speed bound v_maxAnd v_min, then judge v_1,2,v_1,3,v_2,3Whether at speed interval [v_min,v_max] In.If v_1,2,v_1,3,v_2,3All in speed interval, then calculate name spread speed [v_1,2,v_1,3,v_2,3] variance $D\left(v\right)=\frac{1}{3}[{(v_{\mathrm{1,2}}-\stackrel{\‾}{v})}^2+{(v_{\mathrm{1,3}}-\stackrel{\‾}{v})}^2+{(v_{\mathrm{2,3}}-\stackrel{\‾}{v})}^2],$ WhereinIf [v_1,2,v_1,3,v_2,3] do not exist In speed interval, then make variance D (v)=10000.

Find minima in variance D (v) of all grid element center point, and record the coordinate of its central point, and show such as figure 3。

Test below in conjunction with test panel, further illustrate the present invention:

1 experimental condition

Loose-parts monitoring system experiment porch is mainly adjusted by steel plate, industrial computer, acceleration transducer, sound prison device and signal The compositions such as reason device.Experimental system overall framework is as shown in Figure 4.

The test object of experimental system includes steel plate, steel ball and support thereof.Wherein, the size of steel plate be 200 × 200 × 2cm.In order to reduce the impact of environment noise as far as possible, under four edges of steel plate, all add buffering isolation.Each buffering isolation Be made up of 3 pieces of supporting steel plates and 3 blocks of rubber slabs, by bottom respectively supporting steel plate, rubber slab, supporting steel plate, rubber slab, Supporting steel plate, rubber slab, gross thickness about 9.6cm.Wherein, supporting steel plate a size of 20 × 20 × 1.2cm, rubber slab a size of 20 ×20×2cm.Experiment steel ball weight used is respectively 176g, 1400g and 10000g.3 sensors are arranged, such as Fig. 5 on flat board Shown in, to arrange by equilateral triangle, the sample frequency of each sensor is 100kHz.

2 result of the tests and analysis

Positioning result shows as it is shown on figure 3, position of collision is label 1 in Fig. 3, and the vector error of positioning result is (6.667cm,-6.667cm)。

The present invention uses following methods to calculate absolute error and relative error:

Absolute error: E=Δ d, wherein Δ d is the distance between loosening element falls position and positioning result of the present invention.

Relative error:Wherein S is the area that 3 sensors constitute equilateral triangle.

Table 1 176g steel ball impact experiment result log

Table 2 1400g steel ball impact experiment result log

Table 3 10000g steel ball impact experiment result log

By table 1～3 it may be seen that 3 kinds of quality steel balls fall the location average relative error in all positions and are respectively 6.64%, 5.93% and 8.34%, the mass range span of experiment is big, representative, illustrates that the method is to different quality pine Moving part has preferable locating effect.

Content described in the present embodiment is only enumerating of the way of realization to inventive concept, and protection scope of the present invention is not Should be seen as limited by the concrete form that embodiment is stated, protection scope of the present invention is also and in those skilled in the art's root According to present inventive concept it is conceivable that equivalent technologies means.

Claims (6)

1. based on Hilbert transform and the positioning method for loosening member of nuclear power station of data screening, it is characterised in that include following step Rapid:

1) according to positioning accuracy request, it is being knocked grid division on thing, then to ready-portioned grid numbering 1～N；

2) it is being knocked on thing by equilateral triangle layout 3 acceleration transducers of installation, is producing during to obtain loosening element falls Shock signal f (t)；

3) according to the range difference of the geometry computations each grid element center point to each acceleration transducer two-by-two being knocked thing d_i,j；

4) shock signal f (t) received by each acceleration transducer of data collecting card synchronous acquisition, clashes into signal f (t) Including impact signal s (t) during loosening element falls and environmental background noise n (t)；

5) use moving average method to eliminate the low-frequency noise clashing into signal f (t), then use 8 rank Butterworth wave filter by ring Border background noise n (t) filters, and obtains impact signal s (t)；

6) to step 5) in process impact signal s (t) that obtains and be analyzed with Hilbert transform, obtain impact signal s (t) The oscillation starting points moment；Owing to the moment that impact signal s (t) falls cannot be known, can only believe from the impact of 3 acceleration transducers Obtaining the time difference that ripple is propagated in number s (t), the difference time of advent between each two passage is t_i,j；

7) according to propagation distance difference d of grid element center point to each acceleration transducer_i,jWith time of advent between each passage is poor t_i,jCalculate nominal spread speed v of each grid element center point_i,j；

8) speed bound v that bending wave is propagated in the structure is calculated_maxAnd v_min；

9) nominal spread speed v to all grid element center points_i,jCarry out data screening: judge name spread speed v_i,jWhether exist Speed interval [the v that bending wave is propagated_max,v_minIn], if nominal spread speed v of grid element center point_i,jAll at speed interval [v_max,v_minIn], then calculate variance D (v) of the speed of this grid element center point, be assigned to a big value, then otherwise to variance D (v) Make variance D (v)=10000；

10) search for minima in variance D (v) of all grid element center point, record the coordinate of its central point；

11) positioning result shows.

Localization method the most according to claim 1, it is characterised in that: described step 3) in, for plane, according to formula (1) calculating grid element center is to the range difference of each acceleration transducer:

$d_{i,j}=\sqrt{{(x-x_i)}^2+{(y-y_i)}^2}-\sqrt{{(x-x_j)}^2+{(y-y_j)}^2}---\left(1\right)$

Wherein (x y) is the coordinate of grid element center point, (x_i,y_i) it is the coordinate of acceleration transducer i, (x_j,y_j) it is that acceleration passes The coordinate of sensor j, i=1,2,3；J=1,2,3；i≠j；

For hemisphere face, according to the range difference of formula (2) calculating grid element center to each acceleration transducer:

Wherein r is the radius of ball,For the spherical coordinates of grid element center point,For the spherical coordinates of acceleration transducer i,For the spherical coordinates of acceleration transducer j, i=1,2,3；J=1,2,3；i≠j.

Localization method the most according to claim 1, it is characterised in that: described step 5) in, eliminate according to formula (3) and hit Hit signal f (t) low-frequency noise:

$f^{\′}\left(t\right)=\frac{\left(f\right(t)+f(t-1)+...f(t-n+1\left)\right)}{n}---\left(3\right)$

Wherein f'(t) it is the shock signal after rolling average, n is the number in period of rolling average, and n is set to 7.

Localization method the most according to claim 1, it is characterised in that: described step 6) in, according to the peak value of envelope Determine impact signal s (t) the oscillation starting points moment, specifically include following steps:

6.1) Hilbert transform of impact signal s (t) is askedAccording to definition:

$\hat{s}\left(t\right)={\∫}_{-\mathrm{\∞}}^{\mathrm{\∞}}s\left(t\right)\frac{1}{\mathrm{\π}(t-\mathrm{\τ})}d\mathrm{\τ}---\left(4\right)$

Wherein,Hubert transformed signal for impact signal s (t)；

6.2) with impact signal s (t) as real part, its hubert transformed signalFor imaginary part, constitute a new function as public Formula (5):

$z\left(t\right)=s\left(t\right)+j\hat{s}\left(t\right)=\left|z\left(t\right)\right|\exp \left(j\mathrm{\θ}\right(t\left)\right)---\left(5\right)$

Wherein,Being the magnitude function of new function, θ (t) is phase function, and | z (t) | is then impact letter The envelope function of number s (t)；

6.3) | z (t) | the peaking to magnitude function: the relatively amplitude of 6 points that each point is adjacent, if this point is amplitude maximum Value, then the peak value that the amplitude of this point is, taking the time point t corresponding to first peak value tried to achieve is impact signal s (t) In the starting of oscillation moment, calculate the time difference between each acceleration transducer according to formula (6):

t_i,j=t_i-t_j (6)

Wherein, t_iFor the starting of oscillation moment of acceleration transducer i, t_jFor the starting of oscillation moment of acceleration transducer j, i=1,2,3；J= 1,2,3；i≠j.

Localization method the most according to claim 1, it is characterised in that: described step 7) in, calculate name according to formula (7) Justice spread speed v_i,j:

$v_{i,j}=\frac{d_{i,j}}{t_{i,j}}---\left(7\right)$

Wherein, d_i,jFor the range difference of grid element center point to each acceleration transducer two-by-two, t_i,jIt is the arrival between two passages Time difference, i=1,2,3；J=1,2,3；i≠j.

Localization method the most according to claim 1, it is characterised in that: described step 8) in, calculate curved according to (8) formula Bent wave velocity bound v_maxAnd v_min:

$\begin{array}{c}{v}_{\max }=2{{\mathrm{\ω}}_{\max }}^{\frac{1}{2}}{\left(\frac{{\mathrm{Eh}}^3}{12\mathrm{\ρ}\left(1-{\mathrm{\υ}}^2\right)}\right)}^{\frac{1}{4}}\\ v_{\min }=2{{\mathrm{\ω}}_{\min }}^{\frac{1}{2}}{\left(\frac{{\mathrm{Eh}}^3}{12\mathrm{\ρ}\left(1-{\mathrm{\υ}}^2\right)}\right)}^{\frac{1}{4}}\end{array}---\left(8\right)$

Wherein ω_max, ω_minBeing respectively the highest angular frequency of bending wave and minimum angular frequency, E is the Young's modulus of material, and h is quilt The thickness of impacting object, ρ is the density of material, and υ is the Poisson's ratio of material.