CN104515809B - Device and method for identifying identities of power cables based on ultrasonic wave - Google Patents

Abstract

The invention discloses a device for identifying the identities of power cables based on an ultrasonic wave. The device comprises a signal transmission module, a signal receiving module and an information processing and decoding module, wherein the signal transmission module is coupled with one end of one of the power cables to be identified, and transmits a linear frequency modulation vibration signal with specific frequency in a timing mode at equal intervals; the signal receiving module is coupled with the other ends of the power cables to be identified, and is used for receiving the signals of the power cables to be identified; the information processing and decoding module is connected with the signal receiving module, and is used for carrying out related processing such as matched filtering on the received signals to complete the identification of the power cables. The device is used for identifying the complicated power cables without damaging the cables, and is suitable for the identification of the power cables with different thickness; the device is simple in structure, low in cost, convenient to use and higher in safety and reliability.

Description

A kind of power cable identity recognition device based on ultrasonic wave and method

Technical field

The present invention relates to ultrasound detection and analysis technical field are and in particular to arrive a kind of power cable based on ultrasonic wave Personal identification method and device.

Background technology

Underground power cable refers to the electrical lead of below ground that is laid in, because underground pipe network is complicated, and have Direct-buried cable under frozen soil layer, when underground power cable is damaged due to various extraneous or immanent cause, due at it In below ground, human eye is difficult to, and adds that power cable also can occur to be wound around so that underground electric is electric due to due to construction Cable identification increases with changing work difficulty.There is presently no one conveniently identification underground power cable method and Device.

Content of the invention

In consideration of it, it is an object of the invention to provide a kind of power cable identity recognition device based on ultrasonic wave and method, This device passes through the linear frequency modulation vibration signal that transmitting has CF, and matching wave filter combines, and accurately knows Not every different cable, reliability is high, meanwhile, provides a kind of power cable personal identification method.

An object of the present invention is achieved through the following technical solutions, and the purpose of the present invention is by following technical side Case realize, a kind of power cable identity recognition device based on ultrasonic wave, including signal emission module, signal receiving module, Information processing and decoder module data analysis module；

Described signal emission module, is coupled with one end of wherein power cable to be identified, sends out for timing at equal intervals Penetrate a linear frequency modulation vibration signal with CF；

Described signal receiving module, this signal receiving module other end coupling with each power cable to be identified respectively Close, for receiving the signal of power cable to be identified；

Described information is processed and decoder module, is connected with signal receiving module, for the signal receiving is carried out with coupling filter Ripple, completes power cable identification.

Further, described signal emission module includes linear frequency modulation vibration signal generation module, transmitting ultrasonic transducer With a gps clock module, described linear frequency modulation vibration signal generation module is in the effect of a gps clock module pulse per second (PPS) Under, at equal intervals timing transmitting linear frequency modulation vibration signal act on transmitting ultrasonic transducer, this transmitting ultrasonic transducer respectively with One end coupling of each power cable to be identified.

Further, described signal receiving module includes the reception ultrasonic transducer that several are mated with transmitting ultrasonic transducer With to the programmable amplifier that is amplified of output signal receiving ultrasonic transducer, described several receive ultrasonic transducers and treat The other end coupling of identification power cable, each receives ultrasonic transducer and corresponds to a power cable to be identified.

Further, described process and decoder module includes being sequentially connected filtration module, a/d converter, second programmable patrols Collect device fpga and the second microprocessor；Described filtration module is connected with control journey amplifier, for carrying out to the signal after amplifying Filtering；Described a/d converter is used for for filtered signal being converted into data signal；Described second PLD fpga For data signal is carried out with matched filtering, described second microprocessor is connected with the second PLD fpga, according to Root is tied in matched filtering, completes power cable identification.

Further, described information processes and also includes the 2nd gps clock module, described 2nd gps clock mould with decoder module Block is connected with the second microprocessor, the second PLD fpga respectively.

Further, this power cable identity recognition device and method also include display module, described display module and second Microprocessor connects, for showing positioning result.

The second object of the present invention is to provide a kind of power cable personal identification method based on ultrasonic wave, walks including following Rapid:

Signal emission module is coupled by step 1. with one end of wherein power cable to be identified, and is launched with this signal Module produces a linear frequency modulation vibration signal with CF；

Signal receiving module is coupled by step 2. respectively with the other end of each power cable to be identified, and receives electric power The linear frequency modulation vibration signal with CF of cable transmission；

Step 3. information processing and decoder module carry out matched filtering to the echo-signal receiving, and are tied according to matched filtering Fruit is analyzed to signal, and the power cable corresponding to signal amplitude maximum is identified power cable.

Further, also include step 4, after identifying power cable, determine the length of power cable, method particularly includes:

L=(δ t-t_s) v, wherein: l is the length identifying cable；V is ultrasonic signal spread speed in the cable；t_s For the intrinsic system delay of signal emission module and signal receiving module；δ t shakes for the linear frequency modulation that signal emission module sends Dynamic signal and the time difference of receipt signal, wherein

l₁、l₂Represent power cable known to length, δ t₁Represent cable l₁ Middle pumping signal and the time difference of receipt signal, δ t₂Represent cable l₂Middle pumping signal and the time difference of receipt signal.

Due to employing technique scheme, the present invention has the advantage that:

A kind of power cable identity recognition device based on ultrasonic wave proposed by the present invention and method, for complicated electricity Power cable is differentiated, without destroy cable it is adaptable to any thickness power cable identification.Structure is simple, with low cost, Safe and efficient, danger will not be brought to cable itself and testing staff in detection process.Reliability is high, in one section of cable plus ultrasonic Signal, the signal energy of the relatively other cable of the cable corresponding in other end reception ultrasonic vibration signal is the strongest, by coupling After wave filter, add the energy of the energy of ultrasonic signal cable apparently higher than other cable signals.The present invention can be quickly effective Ground differentiates the cable that need to change, and has a good application prospect.

Brief description

In order that the object, technical solutions and advantages of the present invention are clearer, below in conjunction with accompanying drawing the present invention is made into The detailed description of one step, wherein:

Fig. 1 is a kind of structural representation of the power cable identity recognition device based on ultrasonic wave of the present invention；

Fig. 2 is the system block diagram that linear frequency modulation vibration signal of the present invention produces and launches；

Fig. 3 is the coupled modes schematic diagram of transducer of the present invention and cable to be detected；

Fig. 4 is information processing of the present invention and decoder module.

Specific embodiment

Below with reference to accompanying drawing, the preferred embodiments of the present invention are described in detail；It should be appreciated that preferred embodiment Only for the present invention is described, rather than in order to limit the scope of the invention.

As shown in figure 1, a kind of power cable identity recognition device based on ultrasonic wave, including signal emission module, signal Receiver module, information processing and decoder module and display module；

Described signal emission module, is coupled with one end of wherein power cable to be identified, at equal intervals timing transmitting one The individual linear frequency modulation vibration signal with CF；

Described signal receiving module, this signal receiving module other end coupling with each power cable to be identified respectively Close, for receiving the signal of power cable to be identified；

Described information is processed and decoder module, is connected with signal receiving module, for the signal receiving is carried out with coupling filter Ripple, completes power cable identification；

Described display module is connected to information processing and decoder module, for showing positioning result.

As shown in Figure 2,3, 4, described signal emission module includes linear frequency modulation vibration signal generation module, transmitting ultrasonic wave Transducer and gps clock module, specifically, linear frequency modulation vibration signal generation module include first microprocessor (mcu) and First PLD (fpga), first microprocessor is connected with the first PLD, and gps clock module passes through Serial ports is connected with microprocessor, and the pulse per second (PPS) that gps clock module sends acts on the first PLD, at equal intervals timing Transmitting linear frequency modulation vibration signal, after analog-to-digital conversion and high drive, acts on transmitting ultrasonic transducer, launches preset frequency And the linear frequency modulation vibration signal of feature.

Described signal receiving module includes the reception ultrasonic transducer that several are mated with transmitting ultrasonic transducer, and right Receive the programmable amplifier that is amplified of output signal of ultrasonic transducer, described several receive ultrasonic transducers with to be identified The other end coupling of power cable, each receives ultrasonic transducer and corresponds to a power cable to be identified.

In the present embodiment, the section close-coupled of the plane of transmitting ultrasonic transducer and power cable to be identified, from Ultrasonic wave is launched in this direction, and this coupled modes can make the ultrasonic signal energy more preferable receiving end ultrasonic transducer of transmitting Received；Receive ultrasonic transducer also to couple in the other end of power cable in the same way, receive ultrasonic echo.

Described process includes being sequentially connected filtration module, a/d converter, the second PLD with decoder module Fpga, the second microprocessor and the 2nd gps clock module；Described 2nd gps clock module respectively with the second microprocessor, second PLD fpga connects, and the 2nd gps clock module sends pulse per second (PPS) and acts on the second PLD fpga. Described filtration module is connected with control journey amplifier, for being filtered to the signal after amplifying；Described a/d converter is used for filtering Signal after ripple is converted into data signal；Described second PLD fpga is used for data signal is carried out with coupling filter Ripple, described second microprocessor is connected with the second PLD fpga, according to matched filtering result, completes power cable Identification.Second microprocessor calculates according to the output result of matched filter and receives ultrasonic transducer receipt signal The size of amplitude, the power cable corresponding to amplitude maximum is identified power cable.

Based on the design philosophy of said apparatus, the present invention provides a kind of power cable identification side based on ultrasonic wave Method, specifically includes following steps:

Signal emission module is coupled by step 1. with one end of wherein power cable to be identified, and is launched with this signal Module produces a linear frequency modulation vibration signal with CF.

In this step, the expression formula of linear frequency modulation vibration signal is:

$p\left(t\right)=a\left(t\right)\·\exp \left[j2\mathrm{\π}(f_{0}t+\frac{b}{2t}{t}^2)\right]-\frac{t}{2}\≤t\≤\frac{t}{2},$ Wherein, a (t) adjusts for amplitude Function processed, the system adopts rectangular window functionf₀For signal center frequency, t is signal duration, and b is bandwidth. Instantaneous frequency is:It can be seen that linear frequency modulation vibration signal has this linear Instantaneous frequency, inswept scope is [f₀-b/2,f₀+ b/2], this scope is designated as δ f, can get the pulse of linear frequency modulation system Compression ratio is: cr=t × δ f, and therefore, we can increase continuing of signal in the case that inswept frequency range δ f is constant Time, improve the compression ratio of pulse signal, thus improving the signal to noise ratio of system, the reliability of lifting detection.

In the present embodiment, f₀=50khz, t=1ms, b=30khz.

Signal receiving module is coupled by step 2. respectively with the other end of each power cable to be identified, and receives electric power The linear frequency modulation vibration signal of cable transmission, in the present embodiment, calculates for convenience, takes two-way power cable to illustrate.

Step 3. information processing and decoder module carry out matched filtering to the linear frequency modulation vibration signal receiving, according to Join filter result signal is analyzed, the power cable corresponding to signal amplitude maximum is identified power cable.

Two-way receives signal input after programmable amplifier amplification, LPF, a/d conversion that ultrasonic transducer receives To fpga, to two-way transducer received linear frequency modulation vibration signal r in fpga₁(x, t), r₂(x, t) does Fourier transformation, Obtain its frequency spectrum r₁(x, ω), r₂(x, ω) delivers to follow-up matched filter and carries out matched filtering, and matched filter is in fpga Portion realizes.

In the present embodiment, the implementation method of matched filtering is:

1) signal to noise ratio snr is defined as:Wherein r_mT () is the output signal of wave filter, p_n It is average noise power.If the transmission function of passive filter is h (f), signal amplitude after this wave filter is:R herein_iF () is the frequency spectrum of input signal.After this wave filter, noise Power spectrum is:P herein₀For noise power spectrum.

2) by Shi Waxin, then inequality can obtain $\mathrm{snr}\≤\frac{{\&integral;}_{-\∞}^{\∞}{\left|r_i\left(f\right)\right|}^2\mathrm{df}}{p_0},$ When $h\left(f\right)=g_a{r}_i^{*}\left(f\right)e^{-2\mathrm{j\π}{\mathrm{ft}}_1}$ When, obtain equal sign, now corresponding wave filter is matched filter, g_aTake 1, its impulse response is the mirror image of input signal, But it is shifted t on a timeline₁, as: h (t)=g_ar_i(t₁- t), thus know that matched filter can obtain the signal to noise ratio of maximum.

3) spectrum signal being obtained by fpga process is input to again and in matched filter, carries out matched filtering process: coupling Filtered signal is r (x, ω)=r_i(x, ω) h (ω) i=1,2, r_i(x, ω) is input signal, and h (ω) is Fu of h (t) In leaf transformation, filtered output signals r (x, ω) is inputted to microprocessor, and result is shown in lcd.

Due in the present embodiment, wherein two power cables have only been taken to illustrate, then for many electric power electricity For cable, power cable and another Unidentified power cable that will identify that are compared, and compare both amplitudes, until Find the power cable corresponding to signal amplitude maximum, as known power cable.

Further, also include step 5, after identifying power cable, determine the length of power cable, method particularly includes:

L=(δ t-t_s) v, wherein: l is the length identifying cable；V is ultrasonic signal spread speed in the cable；t_s For the intrinsic system delay of signal emission module and signal receiving module；δ t shakes for the linear frequency modulation that signal emission module sends Dynamic signal and the time difference of receipt signal, wherein

l₁、l₂Represent power cable known to length, δ t₁Represent cable l₁ Middle pumping signal and the time difference of receipt signal, δ t₂Represent cable l₂Middle pumping signal and the time difference of receipt signal.

Two known length are taken to be respectively l₁And l₂Cable, tested using this device, linear frequency modulation vibration signal exists First gps clock module pulse per second (PPS) rising edge output, information processing and decoder module end are in the 2nd gps clock module pulse per second (PPS) Rise along starting a/d switching controller, clock control signal clk is sent by a/d switching controller, control the work of a/d converter, and Transformation result is carried out matched filtering, filter result is sequentially stored in twoport ram.Microprocessor search matched filtering result is maximum It is worth corresponding sequence number n₁、n₂, the time difference recording two cables respectively is δ t₁=n₁·t_sWith δ t₂=n₂·t_s, t_sAdopt for ad The sample cycle, thus following equations group can be obtained:

$\left\{\begin{array}{c}{l}_1=({\mathrm{\δt}}_1-t_d)v\\ l_2=({\mathrm{\δt}}_2-t_d)v\end{array}\right.$

Solve: $t_d=\frac{{\mathrm{\δt}}_1{l}_2-{\mathrm{\δt}}_2{l}_1}{l_2-l_1},v=\frac{l_2-l_1}{{\mathrm{\δt}}_2-{\mathrm{\δt}}_1},$ The length of cable can be obtained accordingly；

A kind of power cable personal identification method based on ultrasonic wave proposed by the present invention and device, for complicated electricity Power cable is differentiated, by processing to echo-signal, thus identifying the cable and its length that need to change.

In the present embodiment, the length of cable is obtained using time difference method,

1) l=(δ t-t_s) v, wherein: l is the length of detection cable；V is ultrasonic signal spread speed in the cable；t_s The inherent delay time for signal emission module and signal receiving module；δ t is to send pumping signal, and that is, signal emission module is sent out The linear frequency modulation vibration signal going out and the time difference of receipt signal, the time difference that is, gps clock records.

2) system delay t_sWith asking for of speed v:

Two known length are taken to be respectively l₁And l₂Cable, tested using this device, linear frequency modulation vibration signal exists Gps clock pulse per second (PPS) rising edge exports, and information processing starts second with decoder module end in gps clock pulse per second (PPS) rising edge and can compile A/d switching controller in journey logical device fpga, sends clock control signal clk by a/d switching controller, controls a/d to turn Parallel operation works, and transformation result is carried out matched filtering, and filter result is sequentially stored in twoport ram.Microprocessor search coupling Corresponding sequence number n of filter result maximum₁、n₂, recording the time difference that signal propagates in two cables respectively is δ t₁=n₁· t_sWith δ t₂=n₂·t_s, t_sFor the ad sampling period, thus following equations group can be obtained:

$\left\{\begin{array}{c}{l}_1=({\mathrm{\δt}}_1-t_d)v\\ l_2=({\mathrm{\δt}}_2-t_d)v\end{array}\right.$

Solve: $t_d=\frac{{\mathrm{\δt}}_1{l}_2-{\mathrm{\δt}}_2{l}_1}{l_2-l_1},v=\frac{l_2-l_1}{{\mathrm{\δt}}_2-{\mathrm{\δt}}_1},$ The length of cable can be obtained accordingly.

And the present invention without destroy cable it is adaptable to any thickness power cable identification.

Simple, with low cost, easy to use, the easy realization of structure.

Safe, danger will not be brought to cable itself and testing staff in detection process.

Reliability is high, in one section of cable plus ultrasonic signal, has added the relatively other electricity of cable corresponding to signal in the other end The signal energy of cable is the strongest, and after matched filter, the energy having added ultrasonic signal cable is apparently higher than other cable signals Energy.

The present invention can effectively differentiate the cable that need to change, and has a good application prospect.

The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention it is clear that those skilled in the art Member the present invention can be carried out various change and modification without departing from the spirit and scope of the present invention.So, if the present invention These modifications and modification belong within the scope of the claims in the present invention and its equivalent technologies, then the present invention is also intended to comprise these Including change and modification.

Claims (8)

1. a kind of power cable identity recognition device based on ultrasonic wave it is characterised in that: include signal emission module, signal and connect Receive module and information processing and decoder module；

Described signal emission module, is coupled with one end of wherein power cable to be identified, at equal intervals one tool of timing transmitting There is the linear frequency modulation vibration signal of CF；

Described signal receiving module, this signal receiving module is coupled with the other end of each power cable to be identified respectively, uses There is the linear frequency modulation vibration signal of CF in reception；

Described information is processed and decoder module, is connected with signal receiving module, for having the linear of CF to receive Frequency modulation vibration signal carries out matched filtering, completes power cable identification.

2. a kind of power cable identity recognition device based on ultrasonic wave according to claim 1 it is characterised in that: described Signal emission module includes linear frequency modulation vibration signal generation module, transmitting ultrasonic transducer and a gps clock module, institute State linear frequency modulation vibration signal generation module in the presence of a gps clock module pulse per second (PPS), timing at equal intervals is launched linearly Frequency modulation vibration signal acts on transmitting ultrasonic transducer, this transmitting ultrasonic transducer power cable to be identified with each respectively One end coupling.

3. a kind of power cable identity recognition device based on ultrasonic wave according to claim 2 it is characterised in that: described Signal receiving module includes several with the transmitting reception ultrasonic transducer that mate of ultrasonic transducer with to reception ultrasonic transducer The programmable amplifier that is amplified of output signal, described several receive the another of ultrasonic transducers and power cable to be identified End coupling, each receives ultrasonic transducer and corresponds to a power cable to be identified.

4. a kind of power cable identity recognition device based on ultrasonic wave according to claim 3 it is characterised in that: described Filtration module that information processing and decoder module include being sequentially connected, a/d converter, the second PLD fpga and the Two microprocessors；Described filtration module is connected with programmable amplifier, for being filtered to the signal after amplifying；Described a/d turns Parallel operation is used for for filtered signal being converted into data signal；Described second PLD fpga is used for data signal Carry out matched filtering, described second microprocessor is connected with the second PLD fpga, according to matched filtering result, complete Become power cable identification.

5. a kind of power cable identity recognition device based on ultrasonic wave according to claim 4 it is characterised in that: described Information processing and decoder module also include the 2nd gps clock module, described 2nd gps clock module respectively with the second microprocessor Device, the second PLD fpga connect.

6. a kind of power cable identity recognition device based on ultrasonic wave according to claim 5 it is characterised in that: this electricity Power cable identity identifying device also includes display module, and described display module is connected with the second microprocessor, for display positioning Result.

7. a kind of power cable personal identification method based on ultrasonic wave it is characterised in that: comprise the following steps:

Signal emission module is coupled by step 1. with one end of wherein power cable to be identified, and uses this signal emission module Produce a linear frequency modulation vibration signal with CF；

Signal receiving module is coupled by step 2. respectively with the other end of each power cable to be identified, and receives power cable Echo-signal；

Step 3. information processing and decoder module carry out matched filtering to the echo-signal receiving, according to matched filtering result pair Signal is analyzed, and the power cable corresponding to signal amplitude maximum is identified power cable.

8. a kind of power cable personal identification method based on ultrasonic wave according to claim 7 it is characterised in that: also wrap Include step 4, after identifying power cable, determine the length of power cable, method particularly includes:

L=(δ t-t_s) v, wherein: l is the length identifying cable；V is ultrasonic signal spread speed in the cable；t_sFor letter Number transmitter module system delay intrinsic with signal receiving module；The linear frequency modulation vibration letter that δ t sends for signal emission module Time difference number with receipt signal, wherein

l₁、l₂Represent power cable known to 2 length, δ t₁Represent cable l₁In Pumping signal and the time difference of receipt signal, δ t₂Represent cable l₂Middle pumping signal and the time difference of receipt signal.