Ultrasonic sensor degradation simulation and in-situ correction method, device and apparatus
By acquiring the acoustic impedance parameters of power equipment and sensors, calculating the contact stiffness, and constructing the frequency domain acoustic pressure transmission coefficient equation, the signal dispersion problem caused by sensor coupling agent deterioration was solved, achieving high-precision signal reconstruction and improved monitoring reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA UNIV OF MINING & TECH
- Filing Date
- 2026-04-20
- Publication Date
- 2026-07-14
Smart Images
Figure CN122386221A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power equipment condition monitoring and non-destructive testing technology, and in particular to a method, apparatus and equipment for ultrasonic sensor degradation simulation and in-situ correction. Background Technology
[0002] With the development of smart grids, the number of substations is constantly increasing, as are high-voltage power equipment such as GIS, transformers, and switchgear. High-voltage power equipment is highly susceptible to failure when internal insulation defects occur. Related technologies often employ a combination of ultrasonic (AE) and ultra-high frequency (UHF) detection techniques to monitor partial discharges within high-voltage power equipment. To ensure effective transmission of high-frequency ultrasonic signals, ultrasonic sensors must be tightly attached to the metal casing of the equipment using a coupling agent.
[0003] However, in long-term, complex field operating environments, the coupling agent is highly susceptible to degradation due to temperature fluctuations or aging, such as drying out and detachment, leading to severe attenuation or even distortion of the received partial discharge signal. Current technologies, when assessing sensor coupling degradation, often qualitatively assume that coupling agent degradation causes signal attenuation at a fixed ratio. In laboratory simulations or field verification, degradation is typically simply equated to multiplying by a fixed amplitude attenuation coefficient.
[0004] In reality, the drying of the coupling layer fundamentally alters the micromechanical boundary conditions of the contact surface, resulting in significant differences in the obstruction experienced by sound waves of different frequencies, leading to dispersion and high-frequency filtering effects. Traditional fixed attenuation coefficient models cannot quantitatively characterize the degree of physical degradation of the interface, nor can they scientifically adaptively compensate for distorted signals in the frequency domain based on the actual degradation state on site. This results in serious deviations in the feature extraction of partial discharge signals on site, reducing the diagnostic reliability of the joint monitoring system. Summary of the Invention
[0006] Therefore, it is necessary to provide a method, apparatus, and equipment for simulating and correcting the degradation of ultrasonic sensors in situ, in order to address the aforementioned technical problems.
[0007] Firstly, this application provides a method for simulating and in-situ correcting the degradation of ultrasonic sensors, including:
[0008] S100, obtain the measured acoustic impedance of the casing of the on-site power equipment, and the measured acoustic impedance of the matching layer of the ultrasonic sensor;
[0009] S200: Extract the partial discharge ultrasonic degradation signal collected by the ultrasonic sensor under the energized operation state of the power equipment, and obtain the characteristic cutoff frequency of the partial discharge ultrasonic degradation signal.
[0010] S300: Based on the measured acoustic impedance, the measured acoustic impedance of the ultrasonic sensor, and the characteristic cutoff frequency, calculate the actual microscopic contact stiffness of the contact surface between the ultrasonic sensor and the housing of the power equipment.
[0011] S400 constructs a frequency domain acoustic pressure transmission coefficient equation based on the actual microscopic contact stiffness, and performs frequency domain compensation on the partial discharge ultrasonic degradation signal based on the frequency domain acoustic pressure transmission coefficient equation to generate a reconstructed real partial discharge waveform.
[0012] Optionally, obtaining the measured acoustic impedance of the casing of the on-site power equipment and the measured acoustic impedance of the matching layer of the ultrasonic sensor includes:
[0013] The material density and ultrasonic longitudinal wave velocity of the power equipment casing are obtained by in-situ detection, and the product of the material density and the ultrasonic longitudinal wave velocity is determined as the measured acoustic impedance of the power equipment casing at the site.
[0014] The measured acoustic impedance of the matching layer of the ultrasonic sensor is obtained by measuring the contact surface of the matching layer using a high-frequency acoustic impedance probe.
[0015] Optionally, the step of extracting the partial discharge ultrasonic degradation signal collected by the ultrasonic sensor under the energized operating state of the power equipment, and obtaining the characteristic cutoff frequency of the partial discharge ultrasonic degradation signal, includes:
[0016] Using the partial discharge pulse captured by the ultra-high frequency sensor as the phase reference, the corresponding partial discharge ultrasonic degradation signal is synchronously extracted;
[0017] The partial discharge ultrasonic degradation signal is subjected to a fast Fourier transform to obtain the spectral energy distribution; the high-frequency abruptly decaying centroid of the spectral energy distribution is extracted, and the frequency corresponding to the centroid is converted into an angular frequency and determined as the characteristic cutoff frequency.
[0018] Optionally, the actual microscopic contact stiffness of the contact surface between the ultrasonic sensor and the housing of the power equipment is calculated based on the measured acoustic impedance, the measured acoustic impedance of the ultrasonic sensor, and the characteristic cutoff frequency. The calculation formula is as follows:
[0019] ;
[0020] in, For actual microscopic contact stiffness, The angular frequency corresponding to the characteristic cutoff frequency. The acoustic impedance of the casing of the on-site electrical equipment. Acoustic impedance matching layer for ultrasonic sensors.
[0021] Optionally, the equation for the frequency domain sound pressure transmission coefficient is:
[0022] ;
[0023] in, The frequency domain sound pressure transmission coefficient. Angular frequency, It is the imaginary unit.
[0024] Optionally, the step of performing frequency domain compensation on the partial discharge ultrasonic degradation signal based on the frequency domain acoustic pressure transmission coefficient equation to generate a reconstructed real partial discharge waveform includes:
[0025] Substitute the actual microscopic contact stiffness into the frequency domain acoustic pressure transmission coefficient equation to obtain the transfer function of the current interface degradation.
[0026] The frequency domain sequence of the partial discharge ultrasonic degradation signal is obtained, and the frequency domain sequence is divided by the amplitude-frequency characteristic of the transfer function to obtain the true ultrasonic spectrum.
[0027] Perform an inverse Fourier transform on the actual ultrasonic spectrum to generate a reconstructed actual partial discharge waveform.
[0028] Secondly, this application also provides an ultrasonic sensor degradation simulation and in-situ correction device, comprising:
[0029] The parameter acquisition module is used to acquire the measured acoustic impedance of the casing of the on-site power equipment and the measured acoustic impedance of the matching layer of the ultrasonic sensor.
[0030] The feature extraction module is used to extract the partial discharge ultrasonic degradation signal collected by the ultrasonic sensor under the energized operation state of the power equipment, and to obtain the characteristic cutoff frequency of the partial discharge ultrasonic degradation signal.
[0031] The stiffness calculation module is used to calculate the actual microscopic contact stiffness of the contact surface between the ultrasonic sensor and the housing of the power equipment based on the measured acoustic impedance, the measured acoustic impedance of the ultrasonic sensor, and the characteristic cutoff frequency.
[0032] The in-situ correction module is used to construct a frequency domain acoustic pressure transmission coefficient equation based on the actual micro-contact stiffness, and to perform frequency domain compensation on the partial discharge ultrasonic degradation signal based on the frequency domain acoustic pressure transmission coefficient equation to generate a reconstructed real partial discharge waveform.
[0033] Thirdly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in any of the method embodiments of the first aspect described above.
[0034] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in any of the method embodiments of the first aspect described above.
[0035] The aforementioned method, apparatus, computer equipment, and computer-readable storage medium differ from related technologies that rely on fixed empirical attenuation ratios for verification. First, by acquiring the actual acoustic impedance parameters at the equipment site, a physical model of the non-perfect interface acoustic spring-damped contact is established. Second, by solving the complex transmission equation, the interface degradation characteristics are transformed into a defined high-frequency filtering physical boundary. Third, the unknown microscopic contact stiffness is directly inverted using the centroid characteristic cutoff frequency of the received signal. Finally, the inverted contact stiffness is used to construct a transfer function and perform frequency domain inverse compensation. This method can quantitatively assess the true mechanical degradation indicators of the interface without disassembling the sensor and automatically reconstructs a high-fidelity ultrasonic waveform in the digital monitoring backend, greatly improving the accuracy and reliability of on-site monitoring and sensor verification. Attached Figure Description
[0036] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0037] Figure 1 This is a diagram illustrating the application environment of an ultrasonic sensor degradation simulation and in-situ correction method in one embodiment.
[0038] Figure 2 This is a flowchart illustrating a method for simulating and correcting the degradation of an ultrasonic sensor in an embodiment of this application.
[0039] Figure 3 This is a schematic diagram of the equivalent model of the non-perfect interface acoustic spring damping contact in the embodiments of this application;
[0040] Figure 4 This is a structural block diagram of the in-situ correction device in the embodiments of this application;
[0041] Figure 5 This is a diagram showing the internal structure of a computer device in an embodiment of this application. Detailed Implementation
[0042] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0043] The ultrasonic sensor degradation simulation and in-situ correction method provided in this application can be applied to interactive environments where data acquisition terminals and processing servers communicate. In actual field monitoring, the coupling agent of ultrasonic sensors in high-voltage power equipment (such as GIS, transformers, etc.) is prone to drying out due to aging. This application uses a mechanical boundary model to quantitatively evaluate and correct this phenomenon in situ.
[0044] The ultrasonic sensor degradation simulation and in-situ correction method provided in this application embodiment can be applied to an interactive environment where a data acquisition terminal and a processing server communicate. For example, it can be applied to... Figure 1 In the application environment shown, terminal 102 communicates with server 104 via a network. Specifically, the operator uploads the measured acoustic impedance data of the power equipment casing and the ultrasonic sensor matching layer obtained from on-site detection, as well as the partial discharge ultrasonic degradation signal synchronously acquired by the ultrasonic sensor, to server 104 via terminal 102. Server 104 extracts the characteristic cutoff frequency of the signal and calculates the actual microscopic contact stiffness based on the measured acoustic impedance. Finally, server 104 constructs a frequency domain acoustic pressure transmission coefficient equation based on this contact stiffness and performs frequency domain compensation, outputting the reconstructed real partial discharge waveform result.
[0045] In one exemplary embodiment, such as Figure 2 As shown, a method for simulating and in-situ correcting the degradation of an ultrasonic sensor is provided, including the following steps:
[0046] S100 acquires the acoustic impedance of the enclosure of the field power equipment and the acoustic impedance of the matching layer of the ultrasonic sensor.
[0047] In practice, it is necessary to obtain the acoustic medium properties on both sides of the contact interface. A portable ultrasonic thickness gauge and surface density meter are used for in-situ detection near the mounting point of the equipment casing. For example, to obtain the density of the aluminum alloy casing material. kg / m³, longitudinal wave velocity of ultrasound m / s, multiply the two to calculate the on-site acoustic impedance kg / (m²·s). Simultaneously, the acoustic impedance of the epoxy resin matching layer contact surface of the ultrasonic sensor was directly measured using a piezoelectric high-frequency acoustic impedance probe to obtain its acoustic impedance. kg / (m²·s).
[0048] S200: Extract the partial discharge ultrasonic degradation signal collected by the ultrasonic sensor under the energized operation state of the power equipment, and obtain the characteristic cutoff frequency of the partial discharge ultrasonic degradation signal. During energized operation, the partial discharge pulse captured by the UHF sensor with strong anti-interference capability is used as the phase reference, and the external ultrasonic degradation signal under the same discharge source is simultaneously intercepted. A Fast Fourier Transform (FFT) is performed on this time-domain waveform to extract the centroid point with sharp high-frequency attenuation, which is equivalent to the cutoff frequency of the interface acoustic low-pass filter. Assume the measured extracted characteristic cutoff frequency is... kHz, convert it to angular frequency rad / s.
[0049] S300, calculate the actual microscopic contact stiffness of the contact surface between the ultrasonic sensor and the housing of the power equipment based on the acoustic impedance and the characteristic cutoff frequency.
[0050] like Figure 3 As shown, considering the microscopic degradation characteristics, this embodiment equates the transmission cross section to a non-perfect interface acoustic spring-damped contact model. Characteristic cutoff angular frequency. There is a clear physical relationship between the contact stiffness and the interface. The system performs an inverse transformation to achieve a closed-loop inversion of the microscopic contact stiffness at this point. The calculation formula is as follows:
[0051] ;
[0052] Substituting the aforementioned measured data into the calculation, we can obtain... N / m³. Using this quantification parameter, the system can directly output the current health index of the coupling interface, objectively assessing the degree of dryness.
[0053] S400, construct a frequency domain acoustic pressure transmission coefficient equation based on the actual microscopic contact stiffness, and perform frequency domain compensation on the partial discharge ultrasonic degradation signal based on the frequency domain acoustic pressure transmission coefficient equation to generate a reconstructed real partial discharge waveform.
[0054] Based on the boundary conditions of sound pressure continuity and abrupt change in vibration velocity, a complex frequency domain sound pressure transmission coefficient equation for compensation is constructed:
[0055] ;
[0056] in, The frequency domain sound pressure transmission coefficient. Angular frequency, The unit is the imaginary unit. The true microscopic contact stiffness obtained through inversion... Substituting into the above formula, we establish the exact attenuation transfer function for the current interface coupling degradation of the device. Dividing the frequency domain sequence of the degradation signal actually received by the sensor by this transfer function, we can inversely solve for the true unattenuated ultrasonic spectrum. Finally, by performing an inverse Fourier transform (IFFT) on it, we can reconstruct the broadband internal true ultrasonic partial discharge time domain waveform on the monitoring terminal.
[0057] In one exemplary embodiment, such as Figure 4 As shown, an ultrasonic sensor degradation simulation and in-situ correction device 400 based on a non-perfect contact surface acoustic stiffness model is provided. The device includes: a parameter acquisition module 410, a feature extraction module 420, a stiffness calculation module 430, and an in-situ correction module 440.
[0058] The parameter acquisition module 410 is used to acquire the measured acoustic impedance of the casing of the on-site power equipment and the measured acoustic impedance of the matching layer of the ultrasonic sensor.
[0059] The feature extraction module 420 is used to extract the partial discharge ultrasonic degradation signal collected by the ultrasonic sensor under the energized operation state of the power equipment, and to obtain the characteristic cutoff frequency of the partial discharge ultrasonic degradation signal.
[0060] The stiffness calculation module 430 is used to calculate the actual microscopic contact stiffness of the contact surface between the ultrasonic sensor and the housing of the power equipment based on the measured acoustic impedance, the measured acoustic impedance of the ultrasonic sensor, and the characteristic cutoff frequency.
[0061] The in-situ correction module 440 is used to construct a frequency domain acoustic pressure transmission coefficient equation based on the actual microscopic contact stiffness, and to perform frequency domain compensation on the partial discharge ultrasonic degradation signal based on the frequency domain acoustic pressure transmission coefficient equation to generate a reconstructed real partial discharge waveform.
[0062] Each module in the aforementioned device can be implemented entirely or partially through software, hardware, or a combination thereof. Each module can be embedded in the processor of the computer device in hardware form or independent of it, or it can be stored in the memory of the computer device in software form.
[0063] In one exemplary embodiment, a computer device is provided, the internal structure of which can be as shown in the figure. Figure 5 As shown, the computer device includes a processor, memory, input / output interface, and communication interface connected via a system bus. The processor provides computing and control capabilities; the memory includes non-volatile storage media and internal memory for storing the operating system and computer programs; and the communication interface is used for communication with external devices via a network. When the computer program is executed by the processor, it implements the specific steps in the above-described embodiment of the ultrasonic sensor degradation simulation and in-situ correction method.
[0064] In one embodiment, a computer-readable storage medium is also provided, on which a computer program is stored, which, when executed by a processor, implements the steps in any of the above embodiments of the ultrasonic sensor degradation simulation and in-situ correction method.
[0065] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this application. The above embodiments only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application.
Claims
1. A method for simulating and in-situ correcting the degradation of an ultrasonic sensor, characterized in that, The method includes: S100, to obtain the measured acoustic impedance of the casing of the on-site power equipment, and the measured acoustic impedance of the matching layer of the ultrasonic sensor; S200, extract the partial discharge ultrasonic degradation signal collected by the ultrasonic sensor under the energized operation state of the power equipment, and obtain the characteristic cutoff frequency of the partial discharge ultrasonic degradation signal. S300, calculate the actual microscopic contact stiffness of the contact surface between the ultrasonic sensor and the housing of the power equipment based on the measured acoustic impedance, the measured acoustic impedance of the ultrasonic sensor, and the characteristic cutoff frequency. S400, construct a frequency domain acoustic pressure transmission coefficient equation based on the actual microscopic contact stiffness, and perform frequency domain compensation on the partial discharge ultrasonic degradation signal based on the frequency domain acoustic pressure transmission coefficient equation to generate a reconstructed real partial discharge waveform.
2. The method according to claim 1, characterized in that, The acquisition of the measured acoustic impedance of the casing of the on-site power equipment and the measured acoustic impedance of the ultrasonic sensor matching layer includes: The material density and ultrasonic longitudinal wave velocity of the power equipment casing are obtained by in-situ detection, and the product of the material density and the ultrasonic longitudinal wave velocity is determined as the measured acoustic impedance of the power equipment casing at the site. The measured acoustic impedance of the matching layer of the ultrasonic sensor is obtained by measuring the contact surface of the matching layer using a high-frequency acoustic impedance probe.
3. The method according to claim 1, characterized in that, The step of extracting the partial discharge ultrasonic degradation signal collected by the ultrasonic sensor under the energized operating state of the power equipment, and obtaining the characteristic cutoff frequency of the partial discharge ultrasonic degradation signal, includes: Using the partial discharge pulse captured by the ultra-high frequency sensor as the phase reference, the corresponding partial discharge ultrasonic degradation signal is synchronously extracted; The spectral energy distribution is obtained by performing a fast Fourier transform on the partial discharge ultrasonic degradation signal. Extract the high-frequency centroid of the spectrum energy distribution that decays sharply, convert the frequency corresponding to the centroid into an angular frequency, and determine it as the characteristic cutoff frequency.
4. The method according to claim 1, characterized in that, The actual microscopic contact stiffness of the contact surface between the ultrasonic sensor and the housing of the power equipment is calculated based on the measured acoustic impedance, the measured acoustic impedance of the ultrasonic sensor, and the characteristic cutoff frequency. The calculation formula is as follows: ； in, For actual microscopic contact stiffness, The angular frequency corresponding to the characteristic cutoff frequency. The acoustic impedance of the casing of the on-site electrical equipment. Acoustic impedance matching layer for ultrasonic sensors.
5. The method according to claim 1, characterized in that, The equation for the frequency domain sound pressure transmission coefficient is: ； in, The frequency domain sound pressure transmission coefficient. Angular frequency, It is the imaginary unit.
6. The method according to claim 1, characterized in that, The step of performing frequency domain compensation on the degraded ultrasonic signal of partial discharge based on the frequency domain acoustic pressure transmission coefficient equation to generate a reconstructed real partial discharge waveform includes: Substitute the actual microscopic contact stiffness into the frequency domain acoustic pressure transmission coefficient equation to obtain the transfer function of the current interface degradation. The frequency domain sequence of the partial discharge ultrasonic degradation signal is obtained, and the frequency domain sequence is divided by the amplitude-frequency characteristic of the transfer function to obtain the true ultrasonic spectrum. Perform an inverse Fourier transform on the actual ultrasonic spectrum to generate a reconstructed actual partial discharge waveform.
7. A device for simulating and in-situ correcting the degradation of an ultrasonic sensor, characterized in that, The device includes: The parameter acquisition module is used to acquire the measured acoustic impedance of the casing of the on-site power equipment and the measured acoustic impedance of the matching layer of the ultrasonic sensor. The feature extraction module is used to extract the partial discharge ultrasonic degradation signal collected by the ultrasonic sensor under the energized operation state of the power equipment, and to obtain the characteristic cutoff frequency of the partial discharge ultrasonic degradation signal. The stiffness calculation module is used to calculate the actual microscopic contact stiffness of the contact surface between the ultrasonic sensor and the outer shell of the power equipment based on the measured acoustic impedance, the measured acoustic impedance of the ultrasonic sensor, and the characteristic cutoff frequency. The in-situ correction module is used to construct a frequency domain acoustic pressure transmission coefficient equation based on the actual microscopic contact stiffness, and to perform frequency domain compensation on the partial discharge ultrasonic degradation signal based on the frequency domain acoustic pressure transmission coefficient equation to generate a reconstructed real partial discharge waveform.
8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.
9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.