CN-121978631-A - Method and system for positioning blocking of detector in pipeline by array acoustic wave layered inversion

CN121978631ACN 121978631 ACN121978631 ACN 121978631ACN-121978631-A

Abstract

The application discloses a method and a system for positioning blocking of a detector in a pipeline by array acoustic wave layered inversion, and belongs to the technical field of buried pipeline detection. The method comprises the steps of performing high-precision global synchronization on clocks of the inner detectors, intelligently judging blocking states and triggering sound wave emission, inverting comprehensive sound velocity of an axial pipe soil medium by using a ground axial double-point receiving signal to realize coarse positioning of blocking axial intervals, determining a ground projection center by means of energy peak searching of a mobile probe, arranging a linear receiving array perpendicular to a pipeline to collect sound wave travel time data of radial propagation, and finally obtaining accurate three-dimensional space coordinates by means of combining a linear hyperbolic travel time equation and utilizing least square parameter estimation to jointly reverse local soil sound velocity above blocking points and the buried depth of the inner detectors. According to the application, through physical layering and parameter joint inversion, the influence of non-uniform soil sound velocity uncertainty is eliminated, and the blocking and positioning of the detector in the pipeline with sub-meter precision is realized under a complex geological environment.

Inventors

GU TAO
ZHAO SHUANGQING
GUO XIANGJI
GONG SIFAN
LU HUI
YUAN YE
LIU YANG
LIU WENJIE
ZHU BO
WANG QIANG
ZHOU HAITING
LI YIDE

Assignees

山东省特种设备检验研究院集团有限公司

Dates

Publication Date: 20260505
Application Date: 20260212

Claims (10)

1. The method for positioning the blocking of the detector in the pipeline by using the array acoustic wave layered inversion is characterized by comprising the following steps of: S1, before an inner detector operates, synchronous calibration is carried out on a local clock of an acoustic emission control unit carried by the inner detector by using an external standard time service source, and a global absolute time coordinate system is established; S2, the inner detector monitors the motion state in real time, and when the inner detector judges that the inner detector enters the blocking state, a subsequent acoustic signal transmitting process is triggered; S3, when the internal detector is judged to be in a blocking state, transmitting an acoustic wave signal to a pipeline medium at a preset absolute moment based on the calibrated local clock; S4, arranging at least two receiving points in the estimated axial direction of the ground pipeline, collecting sound wave signals, estimating the comprehensive sound velocity of a pipe soil medium in which sound waves axially propagate through signal processing, and solving the approximate axial distance interval of the blocking point by combining the absolute flight time of the signals; s5, moving a ground receiving probe along the axial direction and the vertical direction of the pipeline in the determined axial distance range, and determining the vertical projection center position of the blocking point on the ground according to the maximum point of the amplitude of the received signal; s6, arranging a linear receiving array perpendicular to the direction of the pipeline by taking the projection center position as a reference, collecting acoustic signals, and obtaining absolute travel time vectors of signals received by array elements; s7, constructing a radial propagation model of sound waves from the inner detector to the ground array element, linearizing a nonlinear travel time equation, simultaneously inverting the local soil sound velocity above the blocking point and the buried depth of the inner detector through a parameter estimation algorithm by utilizing the absolute travel time vector and the array element space coordinate, and combining the determined plane coordinate to realize the accurate determination of the three-dimensional space position of the inner detector.
2. The method for locating a blocking of an in-pipeline detector in array acoustic wave layer inversion according to claim 1, wherein the step of synchronously calibrating a local clock of an acoustic emission control unit carried by the in-pipeline detector by using an external standard time service source comprises the following steps: S11, obtaining a PPS second pulse signal through a GPS receiving module; S12, triggering reset and reset of a counter in the acoustic emission control unit by using the rising edge of the PPS second pulse signal to realize and coordinate the phase synchronization of UTC (universal time code); S13, a high-stability clock source is adopted as an oscillation source of a local clock, wherein the high-stability clock source comprises a constant temperature crystal oscillator OCXO or a temperature compensation crystal oscillator TCXO; S14, recording a time span from the synchronization completion time to the blocking occurrence time, and performing linear compensation correction on the absolute time T0 of sound wave emission according to the nominal drift rate of the crystal oscillator.
3. The method for locating a blocking of an in-pipeline detector for array acoustic wave layer inversion according to claim 1, wherein the in-pipeline detector monitors the motion state in real time, and comprises the following steps: S21, fusing mileage wheel data and inertial measurement unit IMU data by using a Kalman filtering algorithm, and estimating the motion state of the inner detector in real time; S22, if and only if the mileage wheel stop counting time exceeds a preset threshold value and the axial acceleration is continuously lower than a static threshold value, judging that the inner detector enters a blocking state.
4. The method for locating a stuck detector in a pipeline for array acoustic wave layer inversion according to claim 1, wherein the internal detector transmits an acoustic wave signal to a pipeline medium at a preset absolute time based on a calibrated local clock, comprising the following steps: s31, taking a preset timing moment as a transmitting starting point T0; s32, transmitting an acoustic wave signal with high autocorrelation characteristic, wherein the signal is a single-frequency signal or a Linear Frequency Modulation (LFM) signal or a Barker Code modulation pulse signal; s33, selecting a frequency range of the sound wave signal as a preset frequency band; and S34, transmitting periodic signals with the duration of Tdur and the pause interval of TER each time until the blockage is relieved or the inner detector is taken out.
5. The method for locating the blocking of the detector in the pipeline of the array acoustic wave layering inversion according to claim 1, wherein at least two receiving points are arranged in the estimated axial direction of the ground pipeline, acoustic wave signals are collected, and the comprehensive sound velocity of a pipe soil medium in which acoustic waves propagate along the axial direction is estimated through signal processing, comprising the following steps: s41, arranging two known intervals on the ground along the axial direction of the pipeline Each probe is provided with an independent GPS time service module as a first receiving point and a second receiving point and is used for stamping accurate UTC time stamps on received signals; s42, estimating the time delay between two paths of received signals based on the time delay estimation algorithm ; S43, calculating an estimated value of comprehensive sound velocity of the axial pipe soil medium: ; S44, calculating the axial distance from the blocking point to the proximal probe: wherein For the absolute moment of arrival of the acoustic wave at the proximal probe, For the drift-compensated transmit time instant, Is a system hardware response delay.
6. The method for locating a stuck detector in a pipeline for acoustic wave layer inversion according to claim 1, wherein said step S5 comprises the steps of: S51, moving a ground receiving probe along the axial direction of the pipeline in a first preset step length in an axial distance range, recording the amplitude of sound wave signals received by each point, and marking the maximum amplitude point as an axial center position; S52, moving the ground receiving probe at the axial center position in a second preset step length perpendicular to the axial direction of the pipeline, recording the amplitude of the sound wave signal received by each point, and determining the maximum amplitude point as the vertical projection center position of the blocking point on the ground.
7. The method for locating a blocking detector in a pipeline by using array acoustic wave layer inversion according to claim 1, wherein a linear receiving array perpendicular to the direction of the pipeline is arranged based on the projection center position, and the method comprises the following steps: s61, taking the vertical projection center position of the blocking point on the ground as a datum point, and arranging a linear receiving array along the direction vertical to the trend of the pipeline; S62, the linear receiving array consists of at least 3 vertical component detectors, and the detectors are arranged in a straight line at preset intervals; S63, synchronously acquiring the sound wave signals of each array element through the multichannel data acquisition unit.
8. The method for locating a stuck detector in a pipeline for acoustic wave layer inversion according to claim 1, wherein said step S7 comprises the steps of: s71, constructing a radial propagation forward model based on a ray theory, wherein the travel time of the ith array element meets a hyperbolic equation: wherein For the absolute observation time of the ith array element, For the horizontal distance of the ith array element relative to the axial center, H is the inner detector burial depth, Is the local soil sound velocity; S72, squaring and rearranging two sides of the hyperbolic equation to obtain a linearization observation equation: wherein As a gradient parameter related to the square of the medium slowness, Is an intercept parameter related to the square of the equivalent depth; S73, constructing a design matrix H and an observation vector Y, wherein H is formed by Values constitute, Y is composed of Value constitution; S74, solving the parameter vector by least square estimation And : , Wherein, the Is a special case of a vandermonde matrix; s75, based on the parameters alpha and beta obtained by inversion, a physical model is calculated: Estimating local soil sound velocity: ; inner detector burial depth estimation: 。
9. the method for locating a stuck detector in a pipeline for acoustic wave layer inversion according to any one of claims 1 to 8, further comprising step S8: And outputting the inversion result in real time through a portable edge computing terminal, wherein a floating point computing unit FPU is arranged in the portable edge computing terminal and is configured to execute fast Fourier transform FFT, generalized cross-correlation operation and nonlinear least square regression algorithm.
10. An in-pipeline detector blocking and positioning system for array acoustic wave layered inversion, which is characterized by comprising: The system comprises an inner detector cabin body, an inner detector acoustic emission subsystem, a main control unit, a high-precision clock module, a motion state monitoring module, a power amplification module and an acoustic transducer, wherein the main control unit is used for judging a blocking state and controlling the acoustic transducer to emit acoustic signals at a specific moment after blocking; The ground receiving and processing subsystem comprises a GPS time service module, a multichannel data acquisition unit, a linear sensor array and a portable computing terminal, wherein the GPS time service module provides a time reference synchronous with a transmitting end, the linear sensor array is used for acquiring surface acoustic wave signals, the portable computing terminal is used for receiving data and executing comprehensive sound velocity estimation of an axial pipe soil medium, ground center point calibration and radial layering parameter joint inversion algorithm, and three-dimensional coordinates and local soil sound velocity of an inner detector are output.

Description

Method and system for positioning blocking of detector in pipeline by array acoustic wave layered inversion Technical Field The application relates to the technical field of buried pipeline detection, in particular to a method and a system for realizing high-precision three-dimensional space positioning of an inner detector blocked in a pipeline by utilizing an active sound source and a ground linear sensor array to perform signal acquisition and data processing. Background In the process of implementing the present application, the inventor finds that at least the following problems exist in the prior art: In the operation process of the pressure pipeline such as the long oil and gas pipeline, an internal detector (commonly called a pipe cleaner or a Pig) is usually adopted to enter the interior of the pipeline, so that defects such as pipe wall corrosion, cracks and the like are detected on line. However, the inner detector is at risk of jamming due to pipe deformation, deposit accumulation or mechanical failure. Once blocking occurs, the detection task is not only interrupted, but also pipeline transportation stoppage or even safety accidents are more likely to occur, so that the position of the pipeline is required to be quickly and accurately determined for excavation rescue. Conventional methods of internal detector positioning rely primarily on the electromagnetic transmitter and ground marker boxes (Above Ground Marker, AGM) they carry. The method is a 'pass-through' positioning method, and can only confirm that an inner detector passes a certain mark point, and if blocking occurs between two mark points (usually at an interval of 1-3 km), a specific position cannot be determined. The other is based on ultra-low frequency electromagnetic wave portable tracking and positioning, even if the inner detector card ball can realize tracking, the electromagnetic signal strength can be attenuated sharply along with the increase of the distance under the shielding of pipeline signals and the external electromagnetic interference, and the effective detection distance is very short, usually a few meters. The acoustic positioning method provides a new idea for blocking positioning. However, existing acoustic positioning methods generally assume that sound waves propagate in the soil medium at a fixed speed of sound (e.g., 340m/s or 1500 m/s) and calculate the distance therefrom. In practice, the path of sound waves propagating from the blocked inner detector to the ground surface relates to multi-layer heterogeneous media such as 'in-pipe media-pipe wall-anti-corrosion layer-soil', wherein the sound velocity of the soil is obviously influenced by factors such as water content, compactness, soil texture type and the like, and the variation range can reach 300m/s to 2000m/s. If a fixed empirical sound velocity value is adopted, positioning errors of tens of meters or even hundreds of meters are caused, so that the excavation operation fails. Therefore, in a non-uniform soil medium, how to eliminate the systematic error caused by the uncertainty of the sound velocity and realize the three-dimensional positioning of sub-meter precision is a technical problem to be solved in the field of blocking and rescuing of the detector in the pipeline at present. Disclosure of Invention The application provides a method and a system for positioning blocking of a detector in a pipeline by array acoustic wave layered inversion, which are used for solving the technical problem of low positioning precision of blocking of the detector in the pipeline caused by uncertain sound velocity of soil in the background art. The technical scheme adopted by the application for solving the technical problems is as follows: on the one hand, the method for positioning the blocking of the detector in the pipeline by array acoustic wave layering inversion is provided, and comprises the following steps: S1, before an inner detector operates, synchronous calibration is carried out on a local clock of an acoustic emission control unit carried by the inner detector by using an external standard time service source, and a global absolute time coordinate system is established; S2, the inner detector monitors the motion state in real time, and when the inner detector judges that the inner detector enters the blocking state, a subsequent acoustic signal transmitting process is triggered; S3, when the internal detector is judged to be in a blocking state, transmitting an acoustic wave signal to a pipeline medium at a preset absolute moment based on the calibrated local clock; S4, arranging at least two receiving points in the estimated axial direction of the ground pipeline, collecting sound wave signals, estimating the comprehensive sound velocity of a pipe soil medium in which sound waves axially propagate through signal processing, and solving the approximate axial distance interval of the blocking point by combining the absolute flight time of the signa