CN-122017876-A - Power transmission line detection imaging method and system

CN122017876ACN 122017876 ACN122017876 ACN 122017876ACN-122017876-A

Abstract

The invention relates to a power transmission line detection imaging method and system, wherein the method comprises the steps of shooting a power transmission line through a single photon laser radar in a non-interference environment to obtain a first photon distribution histogram, calculating the peak time of each pixel point in the first photon distribution histogram, shooting the power transmission line through the single photon laser radar in the interference environment to obtain a second photon distribution histogram, calibrating the expected time position of a target reflection peak in the second photon distribution histogram according to the peak time of each pixel point in the first photon distribution histogram, calculating the depth distance of each pixel point in the calibrated second photon distribution histogram, and synthesizing the depth distances of the second photon distribution histograms of all pixels in the interference state to obtain a depth distance map of the power transmission line. The invention can synthesize high-precision power transmission line imaging.

Inventors

CHEN JUN
ZHENG LEI
TAO LIBING
Huang Luheng
WU GUANGQI
HUANG YANJIE
YE ZIHAO
YE ZHUORU
CHEN JIANAN
GUO YUANCHAO

Assignees

国网浙江省电力有限公司衢州供电公司

Dates

Publication Date: 20260512
Application Date: 20260126

Claims (10)

1. A power line detection imaging method, comprising: step S1, shooting a power transmission line through a single photon laser radar in an interference-free environment to obtain a first photon distribution histogram of 256 x 256 pixels; step S2, counting the peak time of each pixel point in the first photon distribution histogram; s3, shooting a power transmission line through a single-photon laser radar in an interference environment to obtain a second photon distribution histogram of 256 x 256 pixels; S4, calibrating the expected time position of the target reflection peak in the second photon distribution histogram according to the peak time of each pixel point in the first photon distribution histogram; S5, calculating the depth distance of each pixel point in the calibrated second photon distribution histogram; and S6, synthesizing the depth distances of the second photon distribution histograms of 256 x 256 pixels in the interference state, and obtaining a depth distance map of the power transmission line.
2. The method for power line detection imaging of claim 1, wherein said step S1 of obtaining a 256 x 256 pixel first photon distribution histogram and step S3 of obtaining a 256 x 256 pixel second photon distribution histogram comprises: and performing time-dependent single photon counting on the power transmission line in a non-interference state or an interference state by using a single photon laser radar to obtain photon distribution conditions of 256-256 pixels in 1 frame time, taking total 100 frame data to sum, and obtaining a first photon distribution histogram or a second photon distribution histogram under each pixel.
3. The method for power line detection imaging according to claim 1, wherein the step S4 is characterized in that the method for calibrating the expected time position of the target reflection peak in the second photon distribution histogram according to the peak time of each pixel in the first photon distribution histogram comprises the following steps: modeling scattered echo photons in the second photon distribution histogram using maximum likelihood estimation; Modeling reflected echo photons in the second photon distribution histogram using maximum likelihood estimation in combination with the peak time of each pixel point in the first photon distribution histogram; Superposing and modeling the total echo photons in the second photon distribution histogram according to the scattered echo photons modeled by the maximum likelihood estimation and the reflected echo photons modeled by the maximum likelihood estimation; And carrying out superposition modeling on total echo photons to obtain total distribution, solving the total distribution to obtain the expected time position of the target reflection peak in the second photon distribution histogram, and calibrating the expected time position.
4. A power line detection imaging method according to claim 3, characterized in that: modeling scattered echo photons in the second photon distribution histogram by using maximum likelihood estimation, specifically, enabling the scattered echo photons to be subjected to Gamma distribution in time distribution, wherein a probability density function is as follows: , wherein, Is the attenuation coefficient of the Gamma distribution, The Gamma function is used for representing the normalization factor of Gamma distribution; scattering times for Gamma distribution; Is a time variable representing the time that a photon has elapsed from emission to reflection; Modeling the reflected echo photons in the second photon distribution histogram by combining the peak time of each pixel point in the first photon distribution histogram, specifically, the time distribution of the reflected photons of the target obeys Gaussian distribution, and the probability density function is as follows: the peak time is the true propagation time of the target: , , For the peak time of the first photon distribution histogram for each pixel, Is the first photon distribution histogram Peak time of first photon distribution histogram corresponding to each pixel Wherein, in the collection of the (C), Is the overall standard deviation of the Guass distribution, The average value of the Guass distribution is used for representing the peak time of the target reflected echo; Modeling total echo photons in the second photon distribution histogram by overlapping Gamma distribution And Gaussian distribution And (3) superposing to obtain total echo distribution: , wherein, And Respectively the weight coefficients of the scattered noise and the target signal; Solving the total echo distribution to obtain the expected time of the target reflection peak in the second photon distribution histogram, and calibrating the expected time, specifically, deriving the total echo distribution And solving the equation by =0 to obtain the expected peak time of the scattered echo and the expected peak time of the target reflected echo under the corresponding total echo distribution, and selecting the expected peak time of the target reflected echo close to the interference-free state As expected time of target reflection peak in interference state Expected time of target reflection peak in the second photon distribution histogram Calibrating the second photon distribution histogram by using the time threshold in the second photon distribution histogram as a reference, wherein the time threshold is expressed as follows: ; Wherein, the The expected time of the target reflection peak in the interference state; is a dynamically adjusted time offset.
5. The method for power line detection imaging of claim 4, wherein said dynamically adjusted time offset The method meets the following conditions: When the detected transmission line signal is greater than the preset intensity, namely the attenuation coefficient of Gamma distribution Larger, gamma distributed scattering times Smaller, then decrease When the detected power transmission line is smaller than the preset intensity, namely the attenuation coefficient of Gamma distribution Smaller, gamma distributed scattering times When larger, then increase 。
6. The method for power line detection imaging according to claim 1, wherein the step S2 of calculating the depth distance of each pixel point in the calibrated second photon distribution histogram comprises: The peak time of the second photon distribution histogram of each pixel is identified, the peak time is taken as the real time of the photons emitted by the radar and irradiated to the surface of the power transmission line and reflected back, and the depth distance information of the power transmission line under the pixel is calculated according to the light speed and the peak time: ; Wherein, the Is the first The depth distance corresponding to the individual pixels, In order to achieve the light velocity, the light beam is, Is the first Peak time of the second photon distribution histogram corresponding to the individual pixels.
7. The method for power line detection imaging of claim 1, further comprising filtering the calibrated second photon distribution histogram between step S4 and step S5 to reduce noise, the method comprising: Filtering the scaled second photon distribution histogram using a Savitzky-Golay filter by first selecting a window of data about the filter that slides along the second photon distribution histogram and processes point-by-point for each time variable within the window of data And the photon counting value of the corresponding second photon distribution histogram Y axis is fitted with a low-order polynomial by using a least square method, and the value of each point in the data window is replaced by the fitting value of the point on the low-order polynomial, so that the smoothing effect is achieved.
8. A power line detection imaging system, comprising: the first acquisition module is used for shooting a power transmission line through a single photon laser radar in an interference-free environment to obtain a first photon distribution histogram of 256 x 256 pixels; the first calculation module is used for calculating the peak time of each pixel point in the first photon distribution histogram; The second acquisition module is used for shooting the power transmission line through the single-photon laser radar in an interference environment to obtain a second photon distribution histogram of 256 x 256 pixels; The calibration module is used for calibrating the expected time position of the target reflection peak in the second photon distribution histogram according to the peak time of each pixel point in the first photon distribution histogram; the second calculation module is used for calculating the depth distance of each pixel point in the calibrated second photon distribution histogram; And the synthesis module is used for synthesizing the depth distance of the second photon distribution histogram of 256 x 256 pixels in the interference state to obtain a depth distance map of the power transmission line.
9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor, when executing the computer program, implements the steps of the power line detection imaging method as claimed in any one of claims 1 to 7.
10. A computer-readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the power line detection imaging method as claimed in any one of claims 1 to 7.

Description

Power transmission line detection imaging method and system Technical Field The invention relates to the technical field of power transmission line detection, in particular to a power transmission line detection imaging method and system. Background The detection and inspection of the transmission line are key tasks in the operation and maintenance of the power system. The traditional manual inspection method has the problems of low efficiency, high cost, high risk and the like, so that an automatic transmission line detection algorithm becomes a research hot spot in recent years. Lidar technology, particularly single photon lidar based on single photon avalanche diodes, has become an effective long range target detection technology by virtue of its high sensitivity and high time resolution. However, existing single photon lidars face some challenges in practical applications, especially in complex environments. In conventional single photon lidar imaging, the system determines the distance and morphology of the target by lasing and receiving the echo signal. The single-photon laser radar can work in low illumination and severe environments, so that the single-photon laser radar has natural advantages in the detection of the transmission line. However, the difficulty of power line detection is in the attenuation of the target signal and the interference of noise. Especially in complex environments, the laser signal may be affected by the background noise of multiple scattering, resulting in weakening or complete submersion of the target signal in noise. Conventional target detection methods, such as peak detection and dual parameter estimation, typically employ fixed gating distances or static parametric models for imaging, but these methods often do not effectively address noise interference problems under varying environmental conditions. Peak detection is a classical image imaging method that determines the distance information of a target by extracting peaks in a histogram. However, in a dense fog or an atmosphere unstable environment, the scattering noise can cause the peak value of the target signal to be close to the noise peak value, so that the imaging result is seriously distorted, and the target cannot be clearly distinguished. The dual parameter estimation algorithm models noise by estimating attenuation coefficients and scattering times, thereby achieving separation of the target signals. Although this approach can deal with noise problems to some extent, the accuracy of target detection is still low due to the complexity of the model and uncertainty in parameter estimation, especially in noisy environments. In addition, the dual-parameter estimation method generally depends on a static fog model or fixed parameter configuration, and lacks of adaptability to dynamic environment changes, so that the imaging effect is poor under the interference of factors such as haze, wind speed change and the like. Therefore, how to improve the accuracy of power line detection through a more flexible and intelligent algorithm in a dynamic and complex environment becomes a key problem to be solved in the current laser radar imaging technology. Disclosure of Invention Therefore, the invention aims to solve the technical problem that the detection accuracy is low because the detection imaging of the transmission line is easy to be interfered by noise in the prior art. In order to solve the technical problems, the invention provides a transmission line detection imaging method, which comprises the following steps: step S1, shooting a power transmission line through a single photon laser radar in an interference-free environment to obtain a first photon distribution histogram of 256 x 256 pixels; step S2, counting the peak time of each pixel point in the first photon distribution histogram; s3, shooting a power transmission line through a single-photon laser radar in an interference environment to obtain a second photon distribution histogram of 256 x 256 pixels; S4, calibrating the expected time position of the target reflection peak in the second photon distribution histogram according to the peak time of each pixel point in the first photon distribution histogram; S5, calculating the depth distance of each pixel point in the calibrated second photon distribution histogram; and S6, synthesizing the depth distances of the second photon distribution histograms of 256 x 256 pixels in the interference state, and obtaining a depth distance map of the power transmission line. In one embodiment of the present invention, the method for obtaining a first photon distribution histogram of 256×256 pixels in step S1 and obtaining a second photon distribution histogram of 256×256 pixels in step S3 includes: and performing time-dependent single photon counting on the power transmission line in a non-interference state or an interference state by using a single photon laser radar to obtain photon distribution conditions of 256-2