Impedance characteristic evaluation method, device, apparatus, medium, and program

Abstract

The invention provides an impedance characteristic evaluation method, device, equipment, medium and program. Relates to the technical field of power system management. The method comprises the following steps: injecting a bipolar square wave excitation signal into a grounding grid through a coupling device deployed in the grounding grid; acquiring a high-frequency response signal generated by the grounding grid under the excitation of the bipolar square wave excitation signal through an acquisition device deployed in the grounding grid; decomposing the high-frequency response signal to obtain a resistance spectrum and a reactance spectrum of the grounding grid; by comparing the difference between the total impedance spectrum of the grounding grid and the resistance spectrum and the difference between the total impedance spectrum of the grounding grid and the reactance spectrum, impedance characteristics capable of reflecting the impedance change of the grounding grid along with the frequency are obtained, and the total impedance spectrum of the grounding grid is used for describing the resistance and the impedance at different frequencies when the grounding grid normally works. According to the invention, an accurate and reliable impedance characteristic evaluation effect is achieved.

Description

Technical Field

[0001] This application relates to the field of power system management technology, and in particular to an impedance characteristic evaluation method, apparatus, equipment, medium and procedure. Background Technology

[0002] In power systems, the grounding grid is a critical facility for ensuring the stable operation of electrical equipment and reducing the probability of electric shock. When the grounding grid experiences faults such as conductor corrosion or breakage, it can lead to abnormal operation of electrical equipment and cause serious electrical accidents. Therefore, evaluating the condition of the grounding grid is essential for ensuring the reliable operation of the power system.

[0003] In related technologies, the status of a grounding grid is evaluated by analyzing its high-frequency impedance characteristics. However, it is difficult to capture changes in high-frequency impedance characteristics. When evaluating the status of a grounding grid in complex environments, it is susceptible to interference and has low accuracy.

[0004] Therefore, there is an urgent need for an accurate and reliable impedance characteristic evaluation scheme. Summary of the Invention

[0005] This application provides impedance characteristic evaluation methods, apparatus, equipment, media, and procedures to achieve accurate and reliable impedance characteristic evaluation results.

[0006] Firstly, this application provides a method for evaluating impedance characteristics, including:

[0007] A bipolar square wave excitation signal is injected into the grounding grid through a coupling device deployed in the grounding grid;

[0008] The high-frequency response signal generated by the grounding grid under the excitation of the bipolar square wave excitation signal is acquired by the acquisition device deployed in the grounding grid.

[0009] The high-frequency response signal is decomposed to obtain the resistance spectrum and reactance spectrum of the grounding grid; the resistance spectrum is used to describe the change of the grounding grid's resistance and reactance with frequency; the reactance spectrum is used to describe the change of the grounding grid's resistance with frequency.

[0010] By comparing the differences between the total impedance spectrum and the resistance spectrum of the grounding grid, and the differences between the total impedance spectrum and the reactance spectrum of the grounding grid, the impedance characteristics that reflect the change of grounding grid impedance with frequency are obtained. Among them, the total impedance spectrum of the grounding grid is used to describe the resistance and impedance of the grounding grid at different frequencies when it is working normally.

[0011] In one possible implementation, the high-frequency response signal is decomposed to obtain the resistance spectrum and reactance spectrum of the grounding grid, including:

[0012] The high-frequency response signal is preprocessed to obtain the target high-frequency response signal. The data preprocessing includes noise removal, filtering, and signal calibration.

[0013] The high-frequency response signal of the target is decomposed to obtain the target resistance and target reactance of the grounding grid at different frequencies;

[0014] The resistance spectrum is obtained based on the target resistance of the grounding grid at different frequencies;

[0015] The reactance spectrum is obtained based on the target reactance of the grounding grid at different frequencies.

[0016] In one possible implementation, the target high-frequency response signal is decomposed to obtain the target resistance and target reactance of the grounding grid at different frequencies, including:

[0017] Fourier transform of the target's high-frequency response signal yields the frequency domain response signal and the time domain response signal corresponding to the target's high-frequency response signal;

[0018] Based on the frequency domain response signal and the time domain response signal, the grounding grid impedance is obtained through Ohm's law. The grounding grid impedance includes the impedance of the grounding grid at different frequencies.

[0019] By decomposing the grounding grid impedance, the target resistance and target reactance of the grounding grid at different frequencies can be obtained.

[0020] In one possible implementation, the acquisition device includes a high-frequency voltage sensor and a high-frequency current sensor. The high-frequency response signal includes a high-frequency voltage signal and a high-frequency current signal. The acquisition device, deployed in the grounding grid, acquires the high-frequency response signal of the grounding grid under the excitation of a bipolar square wave excitation signal, including:

[0021] The high-frequency voltage signal of the grounding grid under the excitation of a bipolar square wave excitation signal is collected by a high-frequency voltage sensor deployed in the grounding grid.

[0022] The high-frequency current signal of the grounding grid under the excitation of a bipolar square wave excitation signal is collected by a high-frequency current sensor deployed in the grounding grid.

[0023] In one possible implementation, the total impedance spectrum of the grounding grid is obtained by the following method:

[0024] Based on the load reflection coefficient, wave impedance, and propagation constant of the grounding grid, establish the two-dimensional input impedance relationship of the grounding grid;

[0025] Substituting the excitation function corresponding to the bipolar square wave excitation signal into the two-dimensional input impedance relationship, the grounding grid input impedance corresponding to different frequencies is obtained;

[0026] By summing up the input impedances of the grounding grid at different harmonic frequencies, a total impedance spectrum of the grounding grid that reflects the change of grounding grid impedance with frequency is obtained.

[0027] In one possible implementation, before injecting a bipolar square wave excitation signal into the grounding grid via a coupling device deployed in the grounding grid, the method further includes:

[0028] The bipolar square wave signal is amplified to a preset intensity by a power amplifier to obtain the bipolar square wave excitation signal.

[0029] Secondly, this application provides an impedance characteristic evaluation device, comprising:

[0030] The acquisition module is used to inject a bipolar square wave excitation signal into the grounding grid through a coupling device deployed in the grounding grid; and to acquire the high-frequency response signal generated by the grounding grid under the excitation of the bipolar square wave excitation signal through a data acquisition device deployed in the grounding grid.

[0031] The processing module decomposes the high-frequency response signal to obtain the resistance spectrum and reactance spectrum of the grounding grid. The resistance spectrum describes the change of the grounding grid's resistance and reactance with frequency, while the reactance spectrum describes the change of the grounding grid's resistance with frequency. By comparing the differences between the total impedance spectrum and the resistance spectrum of the grounding grid, and the differences between the total impedance spectrum and the reactance spectrum of the grounding grid, the impedance characteristics that reflect the change of the grounding grid's impedance with frequency are obtained. Among them, the total impedance spectrum of the grounding grid describes the resistance and impedance of the grounding grid at different frequencies when it is working normally.

[0032] In one possible implementation, the processing module is specifically used for:

[0033] The high-frequency response signal is preprocessed to obtain the target high-frequency response signal. The data preprocessing includes noise removal, filtering, and signal calibration.

[0034] The high-frequency response signal of the target is decomposed to obtain the target resistance and target reactance of the grounding grid at different frequencies;

[0035] The resistance spectrum is obtained based on the target resistance of the grounding grid at different frequencies;

[0036] The reactance spectrum is obtained based on the target reactance of the grounding grid at different frequencies.

[0037] In one possible implementation, the processing module is further configured to:

[0038] Fourier transform of the target's high-frequency response signal yields the frequency domain response signal and the time domain response signal corresponding to the target's high-frequency response signal;

[0039] Based on the frequency domain response signal and the time domain response signal, the grounding grid impedance is obtained through Ohm's law. The grounding grid impedance includes the impedance of the grounding grid at different frequencies.

[0040] By decomposing the grounding grid impedance, the target resistance and target reactance of the grounding grid at different frequencies can be obtained.

[0041] In one possible implementation, the acquisition device includes: a high-frequency voltage sensor and a high-frequency current sensor, the high-frequency response signal including a high-frequency voltage signal and a high-frequency current signal, and an acquisition module specifically used for:

[0042] The high-frequency voltage signal of the grounding grid under the excitation of a bipolar square wave excitation signal is collected by a high-frequency voltage sensor deployed in the grounding grid.

[0043] The high-frequency current signal of the grounding grid under the excitation of a bipolar square wave excitation signal is collected by a high-frequency current sensor deployed in the grounding grid.

[0044] In one possible implementation, the processing module is further configured to obtain the total impedance spectrum of the grounding grid by:

[0045] Based on the load reflection coefficient, wave impedance, and propagation constant of the grounding grid, establish the two-dimensional input impedance relationship of the grounding grid;

[0046] Substituting the excitation function corresponding to the bipolar square wave excitation signal into the two-dimensional input impedance relationship, the grounding grid input impedance corresponding to different frequencies is obtained;

[0047] By summing up the input impedances of the grounding grid at different harmonic frequencies, a total impedance spectrum of the grounding grid that reflects the change of grounding grid impedance with frequency is obtained.

[0048] In one possible implementation, before injecting a bipolar square wave excitation signal into the grounding grid via a coupling device deployed in the grounding grid, the processing module is further configured to:

[0049] The bipolar square wave signal is amplified to a preset intensity by a power amplifier to obtain the bipolar square wave excitation signal.

[0050] Thirdly, this application provides an electronic device, including: a memory and a processor;

[0051] The memory stores the instructions that the computer executes;

[0052] The processor executes computer execution instructions stored in memory, causing the processor to perform the first aspect and / or various possible implementations of the first aspect as described above.

[0053] Fourthly, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the first aspect and / or various possible embodiments of the first aspect.

[0054] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the first aspect and / or various possible implementations of the first aspect.

[0055] The impedance characteristic evaluation method, apparatus, equipment, medium, and procedure provided in this application

[0056] By injecting a bipolar square wave excitation signal into the grounding grid through coupling devices deployed within it, a rich frequency response is generated, facilitating accurate acquisition of the grounding grid's impedance at different frequencies. Acquisition devices deployed within the grounding grid collect the high-frequency response signal generated by the grounding grid under the bipolar square wave excitation signal. This captures the high-frequency response signal generated by the grounding grid under the excitation signal and converts it into a processable and analyzable electrical signal form, contributing to a deeper understanding of the grounding grid's electrical performance. Decomposing the high-frequency response signal yields the grounding grid's resistance and reactance spectra; this clearly reveals the characteristics of the grounding grid's resistance and reactance changing with frequency, aiding in the detection of potential faults. By comparing the differences between the total impedance spectrum and the resistance spectrum, and between the total impedance spectrum and the reactance spectrum, accurate and reliable impedance characteristics are obtained. Subsequently, these impedance characteristics provide a more precise understanding of the actual operating conditions of the grounding grid at different frequencies, enabling timely detection of potential local problems or performance changes, and improving the accuracy and reliability of grounding grid fault identification. Attached Figure Description

[0057] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0058] Figure 1 A schematic diagram illustrating a scenario for the impedance characteristic evaluation method provided in an embodiment of this application;

[0059] Figure 2 A flowchart illustrating the impedance characteristic evaluation method provided in the embodiments of this application. Figure 1 ;

[0060] Figure 3 A schematic diagram of a bipolar square wave excitation signal provided in an embodiment of this application;

[0061] Figure 4 A flowchart illustrating the impedance characteristic evaluation method provided in the embodiments of this application. Figure 2 ;

[0062] Figure 5 This is a schematic diagram of a high-frequency response signal provided in an embodiment of this application;

[0063] Figure 6 A schematic diagram of impedance characteristics provided for an embodiment of this application;

[0064] Figure 7 This is a schematic diagram of the impedance characteristic evaluation device provided in the embodiments of this application;

[0065] Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0066] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0067] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0068] In modern power systems, the grounding grid is a crucial facility for ensuring the safe and stable operation of power equipment and protecting personnel from the risk of electric shock. The performance of the grounding grid directly impacts the reliability and safety of the entire power system. For example, the performance of the main grounding grid in a large substation plays a decisive role in ensuring the normal operation of power equipment and protecting personal safety. Because the grounding grid is buried deep underground for extended periods, it is susceptible to natural factors such as soil corrosion, making it prone to conductor corrosion or breakage. This leads to a gradual decline in the grounding performance of the grid, and even its failure. When a grounding grid malfunctions, it can trigger abnormal operation of power equipment, resulting in serious electrical accidents and incalculable losses to power supply and human life. Specifically, power accidents caused by grounding grid failures can not only lead to large-scale power outages, affecting industrial production and residential lives, but also cause permanent damage to power equipment, with high repair costs. Therefore, accurately evaluating the performance status of the grounding grid and promptly identifying potential defects are crucial for ensuring the reliable operation of the power system. In practical operations, grounding grids not only need to withstand power frequency currents, but may also be subjected to high-frequency transient currents such as lightning strikes and switching overvoltages. When the grounding grid is subjected to the impact of high-frequency transient currents, it exhibits complex high-frequency impedance characteristics, and these characteristics play a crucial role in the grounding effect during transient processes.

[0069] In related technologies, the condition of a grounding grid is evaluated by analyzing its high-frequency impedance characteristics. Sine wave excitation is typically used to analyze these characteristics; however, due to the single frequency of the sine wave signal, it is difficult to comprehensively reflect the characteristic changes of the grounding grid over a wide frequency range. Furthermore, sine wave excitation analysis struggles to accurately capture the effects of the skin effect and proximity effect on the effective resistance and inductance of the grounding grid conductors. In addition, the high-frequency interference caused by transient currents in power systems is complex, making the high-frequency impedance characteristic analysis results under sine wave excitation susceptible to high-frequency interference, leading to reduced measurement accuracy and making it impossible to accurately and reliably analyze the grounding grid's impedance characteristics, thus hindering an accurate evaluation of the grounding grid's condition. Therefore, evaluating the condition of a grounding grid in complex environments suffers from susceptibility to interference and low accuracy.

[0070] The impedance characteristic evaluation method provided in this application, through a coupling device deployed in the grounding grid, injects a bipolar square wave excitation signal into the grounding grid, exciting the grounding grid to generate rich frequency responses, which helps to accurately obtain the impedance of the grounding grid at different frequencies. Through a data acquisition device deployed in the grounding grid, the high-frequency response signal generated by the grounding grid under the excitation signal of the bipolar square wave is acquired. This captures the high-frequency response signal generated by the grounding grid under the action of the excitation signal and converts the high-frequency response signal into a processable and analyzable electrical signal form, which helps to gain a deeper understanding of the electrical performance of the grounding grid. Decomposing the high-frequency response signal yields the resistance spectrum and reactance spectrum of the grounding grid; this clearly shows the characteristics of the grounding grid's resistance and reactance changing with frequency, helping to discover potential faults in the grounding grid. By comparing the differences between the total impedance spectrum and the resistance spectrum, and the differences between the total impedance spectrum and the reactance spectrum, accurate and reliable impedance characteristics are obtained. Subsequently, through the impedance characteristics, the actual working condition of the grounding grid at different frequencies can be understood more accurately, and potential local problems or performance changes in the grounding grid can be detected in a timely manner, improving the accuracy and reliability of grounding grid fault identification.

[0071] Figure 1 This is a schematic diagram illustrating a scenario for the impedance characteristic evaluation method provided in an embodiment of this application. Figure 1 As shown, the specific application scenario of this application includes a grounding grid 11, a data acquisition device 12, a coupling device 13, and a control center 14, wherein:

[0072] Several data acquisition devices 12 and several coupling devices 13 are deployed in the grounding grid 11.

[0073] The control center 12 is communicatively connected to the coupling device 13. The control center 12 can control the coupling device 13, so that the coupling device 13 injects a bipolar square wave excitation signal into the grounding grid 11.

[0074] The control center 12 is communicatively connected to the acquisition device 12. The control center 12 can control the acquisition device 12 to acquire the high-frequency response signal generated by the grounding grid 11 under the excitation of the bipolar square wave excitation signal after the grounding grid 11 is injected with a bipolar square wave excitation signal.

[0075] After acquiring the high-frequency response signal, the acquisition device 12 can send the high-frequency response signal to the control center 12 through the communication connection between the acquisition device 12 and the control center 12.

[0076] After receiving the high-frequency response signal, the control center 12 can obtain the impedance characteristics that reflect the change of grounding grid impedance with frequency based on the high-frequency response signal.

[0077] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0078] Figure 2 A flowchart illustrating the impedance characteristic evaluation method provided in the embodiments of this application. Figure 1 .like Figure 2 As shown, the method includes:

[0079] S201. A bipolar square wave excitation signal is injected into the grounding grid through a coupling device deployed in the grounding grid.

[0080] Deploying coupling devices at appropriate locations within the grounding grid allows bipolar square wave excitation signals to be injected into the grounding grid, exciting it to generate rich frequency responses. This helps to accurately obtain the impedance of the grounding grid at different frequencies.

[0081] A grounding grid is a structure that reliably conducts fault current into the earth when a grounding fault occurs in a power system or building, thereby ensuring the safety of people and equipment. Optionally, the grounding grid is a mesh structure made of metal conductors.

[0082] A coupling device is a device used to transmit and couple a bipolar square wave excitation signal between a bipolar square wave excitation signal generator and a grounding grid. By deploying a coupling device in the grounding grid, the bipolar square wave excitation signal is injected into the grounding grid, ensuring that the bipolar square wave excitation signal is effectively and stably transmitted to the grounding grid.

[0083] A bipolar square wave excitation signal is a square wave signal with both positive and negative polarities. It exhibits periodic high and low level changes on the time axis, meaning it is a periodic non-sinusoidal component. The "bipolar" aspect indicates that the level changes within the bipolar square wave excitation signal encompass both positive and negative voltages. The bipolar square wave excitation signal possesses rich frequency components, enabling it to excite grounding grids to generate response signals of various frequencies.

[0084] The bipolar square wave excitation signal can be expanded into a Fourier series, meaning it can be decomposed into a superposition of sinusoidal quantities with different frequencies, where the sinusoidal quantities include the fundamental wave and a series of odd harmonics. Optionally, the odd harmonics include one or more of any odd harmonics such as the 3rd, 5th, and 7th harmonics.

[0085] Bipolar square wave excitation signal It can be represented as:

[0086]

[0087] in, Indicates positive amplitude; The value indicates a negative amplitude; T represents the period of the bipolar square wave excitation signal; t represents time.

[0088] Figure 3 This is a schematic diagram of a bipolar square wave excitation signal provided in an embodiment of this application. Figure 3 As shown, Figure 3 The amplitude of the bipolar square wave excitation signal shown is ,in:

[0089] The horizontal axis represents time, marking key time points -T, 0, and T in the bipolar square wave excitation signal. The vertical axis represents voltage values, indicating the alternating jumps between positive and negative amplitudes in the bipolar square wave excitation signal waveform, where the positive amplitude is... negative amplitude .

[0090] The waveform of the bipolar square wave excitation signal is symmetrical about the origin, and the amplitudes of the positive and negative half-cycles are equal. Furthermore, the time width of the bipolar square wave excitation signal is the same. Each cycle of the bipolar square wave excitation signal contains two rectangular pulse waveforms with opposite phases.

[0091] The wavelengths corresponding to each frequency component of the bipolar square wave excitation signal satisfy the wavelength formula. Specifically, the wavelength formula can be expressed as:

[0092]

[0093] in, Indicates the wavelength corresponding to each frequency component; The propagation speed of the bipolar square wave excitation signal in the grounding grid; The frequency of the bipolar square wave excitation signal is denoted as .

[0094] Then the fundamental frequency Corresponding wavelength It can be represented as:

[0095]

[0096] but Subharmonic frequency (n=1,3,5,...,2n-1) corresponding wavelengths It can be represented as:

[0097]

[0098] S202. The high-frequency response signal generated by the grounding grid under the excitation of the bipolar square wave excitation signal is acquired by the acquisition device deployed in the grounding grid.

[0099] Because the bipolar square wave excitation signal contains multiple frequency components, the grounding grid will respond to these components, resulting in a high-frequency response signal. A data acquisition device is deployed at a suitable location within the grounding grid to collect the high-frequency response signal generated by the grounding grid under the bipolar square wave excitation signal. Optionally, suitable locations include one or more of the following: the edge of the grounding grid, branch nodes, and areas where potential faults may exist.

[0100] A data acquisition device is used to collect high-frequency response signals from a grounding grid. It captures the high-frequency response signals generated by the grounding grid under the action of an excitation signal and converts these signals into a processable and analyzable electrical signal form.

[0101] High-frequency response signals are electrical signals of different frequencies generated by a grounding grid under the excitation of a bipolar square wave excitation signal. These signals contain characteristic information of the grounding grid at different frequencies, which helps to gain a deeper understanding of the grounding grid's electrical performance.

[0102] S203. Decompose the high-frequency response signal to obtain the resistance spectrum and reactance spectrum of the grounding grid; the resistance spectrum is used to describe the change of the grounding grid's resistance and reactance with frequency; the reactance spectrum is used to describe the change of the grounding grid's resistance with frequency.

[0103] The acquired high-frequency response signal is decomposed using a suitable signal decomposition algorithm to obtain the decomposed result. Then, the decomposed result is analyzed to obtain the resistance spectrum and reactance spectrum of the grounding grid. Optionally, the signal decomposition algorithm includes Fourier transform.

[0104] A resistance spectrum describes how the resistive component of a grounding grid's impedance changes with frequency. Resistance is the frequency-independent part of a grounding grid's opposition to current.

[0105] The reactance spectrum reflects the variation of grounding grid reactance with frequency, including changes in inductive and capacitive reactance. Reactance is the frequency-dependent component of the grounding grid's impedance to current.

[0106] By decomposing the high-frequency response signal, the resistance spectrum and reactance spectrum can be obtained, which can clearly understand the characteristics of the grounding grid resistance and reactance as a function of frequency, and help to discover potential faults in the grounding grid.

[0107] S204. By comparing the differences between the total impedance spectrum and the resistance spectrum of the grounding grid, and the differences between the total impedance spectrum and the reactance spectrum of the grounding grid, the impedance characteristics that reflect the change of the grounding grid impedance with frequency are obtained. Among them, the total impedance spectrum of the grounding grid is used to describe the resistance and impedance of the grounding grid at different frequencies when it is working normally.

[0108] The total impedance spectrum of a grounding grid describes the overall resistance and reactance of the grounding grid at different frequencies under normal operating conditions. It reflects the overall impedance characteristics of the grounding grid to currents of different frequencies. Impedance characteristics are the regularity and features of how the impedance of a grounding grid changes with frequency in actual operation.

[0109] By comparing the differences between the total impedance spectrum and resistance spectrum of the grounding grid under normal operating conditions, the resistance difference of the grounding grid is obtained. Similarly, the difference between the total impedance spectrum and reactance spectrum of the grounding grid is obtained, resulting in the reactance difference. Analyzing these resistance and reactance differences leads to the impedance characteristics of the grounding grid. These impedance characteristics provide a more accurate understanding of the actual operating conditions of the grounding grid at different frequencies, enabling timely detection of potential local problems or performance changes, and improving the accuracy and reliability of grounding grid fault identification.

[0110] The impedance characteristic evaluation method provided in this application, through a coupling device deployed in the grounding grid, injects a bipolar square wave excitation signal into the grounding grid, exciting the grounding grid to generate rich frequency responses, which helps to accurately obtain the impedance of the grounding grid at different frequencies. Through a data acquisition device deployed in the grounding grid, the high-frequency response signal generated by the grounding grid under the excitation signal of the bipolar square wave is acquired. This captures the high-frequency response signal generated by the grounding grid under the action of the excitation signal and converts the high-frequency response signal into a processable and analyzable electrical signal form, which helps to gain a deeper understanding of the electrical performance of the grounding grid. Decomposing the high-frequency response signal yields the resistance spectrum and reactance spectrum of the grounding grid; this clearly shows the characteristics of the grounding grid's resistance and reactance changing with frequency, helping to discover potential faults in the grounding grid. By comparing the differences between the total impedance spectrum and the resistance spectrum, and the differences between the total impedance spectrum and the reactance spectrum, accurate and reliable impedance characteristics are obtained. Subsequently, through the impedance characteristics, the actual working condition of the grounding grid at different frequencies can be understood more accurately, and potential local problems or performance changes in the grounding grid can be detected in a timely manner, improving the accuracy and reliability of grounding grid fault identification.

[0111] Figure 4 A flowchart illustrating the impedance characteristic evaluation method provided in the embodiments of this application. Figure 2 .like Figure 4 As shown, in this embodiment... Figure 2 Based on the examples, the impedance characteristic evaluation method is described in detail, which includes:

[0112] In one possible implementation, the acquisition device includes a high-frequency voltage sensor and a high-frequency current sensor, and the high-frequency response signal includes a high-frequency voltage signal and a high-frequency current signal. Step S202 may further include:

[0113] S2021. High-frequency voltage signals generated by the grounding grid under the excitation of bipolar square wave excitation signals are collected by high-frequency voltage sensors deployed in the grounding grid.

[0114] A high-frequency voltage sensor is deployed in the grounding grid according to a specific connection method. When a bipolar square wave excitation signal is injected into the grounding grid, a corresponding voltage change is generated. The high-frequency voltage sensor senses this voltage change in real time and converts it into a measurable electrical signal. The acquired high-frequency voltage signal is then transmitted to subsequent data processing equipment via a data transmission line. A high-frequency voltage sensor is a sensor specifically designed for measuring high-frequency voltage signals. It possesses high frequency response characteristics and can accurately measure the high-frequency voltage signal generated by the grounding grid under bipolar square wave excitation signal excitation over a wide frequency range.

[0115] S2022. High-frequency current signals of the grounding grid under bipolar square wave excitation signals are collected by high-frequency current sensors deployed in the grounding grid.

[0116] Connect the high-frequency current sensor to the grounding grid. When a bipolar square wave excitation signal is injected into the grounding grid, a high-frequency current will flow through the grounding grid. The high-frequency current sensor senses the change in current through the principle of electromagnetic induction and converts the change in current into a voltage signal, thus obtaining a high-frequency current signal.

[0117] Optionally, the high-frequency current sensor can be sleeved on the conductor of the grounding grid, or a through-type high-frequency current sensor can be clamped on the grounding lead wire to achieve electrical connection between the high-frequency current sensor and the grounding grid.

[0118] In one possible implementation, step S203 may further include:

[0119] S2031. Perform data preprocessing on the high-frequency response signal to obtain the target high-frequency response signal. Data preprocessing includes noise removal, filtering, and signal calibration.

[0120] Data preprocessing is a series of processing operations performed on high-frequency response signals. Through data preprocessing, the data quality and usability of high-frequency response signals can be improved. Preprocessing high-frequency response signals can eliminate interference factors, enabling the target high-frequency response signal to more accurately and clearly reflect the characteristics of the grounding grid.

[0121] Noise removal eliminates random or irrelevant fluctuations in the high-frequency response signal, improving its signal-to-noise ratio. Filtering allows signals within specific frequency ranges to pass through while blocking signals from other ranges, removing unwanted frequency components and retaining the target high-frequency response signal relevant to the grounding grid characteristics. Signal calibration corrects and adjusts the high-frequency response signal to eliminate biases introduced during acquisition by equipment errors and environmental factors, ensuring the acquired signal accurately reflects the true state of the grounding grid.

[0122] By selecting multiple appropriate data preprocessing methods and processing the high-frequency response signal sequentially, the target high-frequency response signal is obtained.

[0123] For example, the selected data preprocessing algorithms are wavelet denoising, bandpass filter denoising, and calibration algorithms. Accordingly, the high-frequency response signal is preprocessed to obtain the target high-frequency response signal, including: first, using wavelet denoising and other algorithms to eliminate noise in the high-frequency response signal to obtain a denoised signal; then, using a bandpass filter denoising method to filter the denoised signal to obtain a filtered signal; finally, using a known standard signal or reference data, the filtered signal is processed by a calibration algorithm to obtain the target high-frequency response signal.

[0124] S2032. Decompose the high-frequency response signal of the target to obtain the target resistance and target reactance of the grounding grid at different frequencies.

[0125] The target resistance is the frequency-independent portion of the grounding grid's resistance to current at different frequencies. The target reactance is the frequency-dependent portion of the grounding grid's resistance to current at different frequencies, including inductive reactance and capacitive reactance.

[0126] First, a signal decomposition method is selected to decompose the target high-frequency response signal into signal components of different frequencies. Then, based on the calculation formulas for resistance and reactance, the resistance and reactance of the grounding grid at each frequency are extracted from the signal components of each frequency. Subsequently, based on the resistance and reactance of the grounding grid at each frequency, the target resistance and target reactance of the grounding grid at different frequencies are obtained. By decomposing the target high-frequency response signal to obtain the target resistance and target reactance of the grounding grid at different frequencies, the characteristics of the grounding grid resistance and reactance changing with frequency can be clearly understood.

[0127] S2033. Based on the target resistance of the grounding grid at different frequencies, the resistance spectrum is obtained.

[0128] The target resistances of the grounding grid at different frequencies are organized and arranged in order of frequency magnitude, and a resistance spectrum is established with frequency as the x-axis and target resistance as the y-axis. The resistance spectrum can intuitively display the characteristics of the grounding grid resistance changing with frequency, allowing maintenance personnel to quickly understand the resistance of the grounding grid at different frequencies.

[0129] S2034. Based on the target reactance of the grounding grid at different frequencies, the reactance spectrum is obtained.

[0130] The target reactance of the grounding grid at different frequencies is organized and arranged in frequency order, and a reactance spectrum is established with frequency as the x-axis and target reactance as the y-axis. The reactance spectrum can intuitively show the characteristics of the grounding grid reactance changing with frequency, and can accurately evaluate the grounding grid's ability to impede alternating current, so that operation and maintenance personnel can understand the reactance of the grounding grid at different frequencies.

[0131] In one possible implementation, step S2032 may further include:

[0132] Step A: Perform a Fourier transform on the target high-frequency response signal to obtain the frequency domain response signal and time domain response signal corresponding to the target high-frequency response signal.

[0133] The Fourier transform algorithm is used to process the target's high-frequency response signal. First, the target's high-frequency response signal is input into the calculation module corresponding to the Fourier transform. Then, in the calculation module, according to the mathematical formula of the Fourier transform, the target's high-frequency response signal is transformed from the time domain to the frequency domain, obtaining the frequency domain response signal. The original target high-frequency response signal is then used as the time domain response signal. Obtaining both the frequency domain and time domain response signals through Fourier transform allows for analysis of the target's high-frequency response signal from different perspectives. The frequency domain response signal helps in understanding the frequency components and distribution of the signal; the time domain response signal can be used to observe transient changes and other characteristics of the signal.

[0134] The Fourier transform converts a time-domain signal to a frequency-domain signal. The target's high-frequency response signal describes how the signal changes over time; it is a time-domain signal, and therefore can be directly used as the time-domain response signal for subsequent processing. The frequency-domain signal describes the distribution of the signal across different frequency components. Through the Fourier transform, the complex target high-frequency response signal can be decomposed into a superposition of sine and cosine signals of different frequencies, yielding the frequency-domain response signal. The frequency-domain response signal allows for the analysis of the signal's frequency characteristics.

[0135] Step B: Based on the frequency domain response signal and the time domain response signal, obtain the grounding grid impedance using Ohm's law. The grounding grid impedance includes the impedance of the grounding grid at different frequencies.

[0136] Using Ohm's law, we obtain the equation that the product of the frequency domain response signal and the time domain response signal equals the grounding grid impedance. By substituting the frequency domain response signal and the time domain response signal into this equation and solving for the impedance, we obtain the grounding grid impedance. The grounding grid impedance is the total resistance of the grounding grid to alternating current at different frequencies, comprehensively reflecting the resistance and reactance characteristics of the grounding grid at different frequencies. By determining the impedance of the grounding grid at different frequencies, we can obtain the grounding grid impedance and gain a comprehensive understanding of the grounding grid's resistance characteristics to alternating current.

[0137] Step C: Decompose the grounding grid impedance to obtain the target resistance and target reactance of the grounding grid at different frequencies.

[0138] The grounding grid impedance is a complex number. By decomposing the grounding grid impedance, we can obtain its real and imaginary parts at different frequencies. Then, we take the real part of the grounding grid impedance at different frequencies as the target resistance and the imaginary part as the target reactance. By decomposing the grounding grid impedance into target resistance and target reactance, we can understand the resistive and reactive characteristics of the grounding grid at different frequencies.

[0139] In one possible implementation, the total impedance spectrum of the grounding grid is obtained by the following method:

[0140] Step A: Establish the two-dimensional input impedance relationship of the grounding grid based on the load reflection coefficient, wave impedance, and propagation constant of the grounding grid.

[0141] The load reflection coefficient reflects the amplitude and phase relationship between the incident and reflected waves in a grounding grid. The value of the load reflection coefficient depends on the matching degree between the load impedance and the characteristic impedance of the transmission line. When the load impedance and the characteristic impedance are equal, the reflection coefficient is 0, indicating no reflection; when they are not equal, the reflection coefficient is not 0, and reflected waves will be generated.

[0142] Wave impedance is the ratio of voltage wave to current wave in a grounding grid, reflecting the grounding grid's obstruction of electromagnetic wave propagation. The value of wave impedance is related to factors such as the grid's geometry and dielectric properties.

[0143] The propagation constant describes the amplitude attenuation and phase change of an electromagnetic wave propagating in a transmission line grounding grid. The real part of the propagation constant represents amplitude attenuation, and the imaginary part represents phase change. The propagation constant is related to the parameters of the grounding grid and the frequency of the signal input to the grounding grid.

[0144] Two-dimensional input impedance relationship: Establish a two-dimensional correlation between the grounding grid input impedance and parameters such as load reflection coefficient, wave impedance, and propagation constant.

[0145] First, it is assumed that the grounding grid is horizontal, and vertical grounding electrodes and natural grounding electrodes in the grounding grid are ignored; that is, only the horizontal grounding grid is considered. Simultaneously, it is assumed that the mutual inductance and mutual resistance parameters of each conductor in the grounding grid are the same, where the mutual inductance parameter of each conductor is the average of the total mutual inductance parameters of all conductors in the grounding grid; and the mutual resistance parameter of each conductor is the average of the total mutual resistance parameters of all conductors in the grounding grid. It is also assumed that the lateral and longitudinal distribution parameters of each conductor are the same, and weak coupling between different conductors is ignored. Then, based on the load reflection coefficient, wave impedance, and propagation constant of the grounding grid, a two-dimensional input impedance relationship is established.

[0146] For example, two-dimensional input impedance relationship and It can be represented as:

[0147]

[0148] in, This represents the input impedance relationship on the horizontal axis; This represents the input impedance relationship along the vertical axis; Indicates the load reflection coefficient; Indicates wave impedance; Represents the propagation constant; Point Voltage phasor at the location; Point The current phasor at that location.

[0149] Step B: Substitute the excitation function corresponding to the bipolar square wave excitation signal into the two-dimensional input impedance relationship to obtain the grounding grid input impedance corresponding to different frequencies.

[0150] The excitation function corresponding to a bipolar square wave excitation signal is a mathematical description of the bipolar square wave excitation signal. The excitation function contains information such as the frequency components, amplitude, and phase of the bipolar square wave excitation signal. Through Fourier transform, the time-domain bipolar square wave signal can be converted into a superposition of multiple sinusoidal signals of different frequencies, thus obtaining the excitation function corresponding to the frequency-domain bipolar square wave signal. Since the grounding grid has different response characteristics to signals of different frequencies, the input impedance of the grounding grid changes with the frequency of the input bipolar square wave excitation signal. By substituting the excitation function into a two-dimensional input impedance relationship, the input impedance values ​​of the grounding grid at each frequency component can be calculated, thereby understanding the electromagnetic characteristics of the grounding grid at different frequencies.

[0151] First, a Fourier transform is performed on the bipolar square wave excitation signal, decomposing it into multiple sinusoidal signal components of different frequencies, thus obtaining the excitation function corresponding to the bipolar square wave excitation signal. Then, the excitation function for each frequency is substituted into the two-dimensional input impedance relationship to calculate the input impedance value of the grounding grid at each frequency. This process of substituting the excitation function for different frequencies into the two-dimensional input impedance relationship is repeated to obtain the corresponding grounding grid input impedance at different frequencies.

[0152] Since even-symmetric bipolar square wave excitation signals also lack a constant term, decomposing them yields a superposition of cosine functions. Because the sine and cosine functions differ by a factor of... The bipolar square wave of an even function lags behind the bipolar square wave of an odd function. Therefore, the numerical values ​​of the odd-symmetric bipolar square wave excitation signal and the even-symmetric bipolar square wave excitation signal are the same after decomposition. For ease of calculation, only the odd-symmetric bipolar square wave is considered.

[0153] For example, due to the odd-symmetric bipolar square wave excitation signal There is no constant term; the bipolar square wave excitation signal... After Fourier series decomposition, the excitation function corresponding to the bipolar square wave excitation signal can be obtained. :

[0154]

[0155] The excitation function corresponding to the bipolar square wave excitation signal After sorting, we can obtain:

[0156]

[0157] in, This indicates the amplitude of the bipolar square wave excitation signal; This represents the fundamental frequency of the bipolar square wave excitation signal, and ; This indicates the period of the bipolar square wave excitation signal.

[0158] The excitation function corresponding to the bipolar square wave excitation signal Substituting into the two-dimensional input impedance relationship and The grounding grid input impedance at different frequencies was calculated. for:

[0159]

[0160] in, The load impedance; Let n be the nth frequency component, and ; Indicates wave impedance; Represents the propagation constant; This indicates the equivalent length of the grounding grid.

[0161] Furthermore, characteristic impedance and propagation coefficient It can be represented as:

[0162]

[0163] in, This is the nth frequency component; Represents resistance per unit length; Indicates inductance per unit length; Indicates conductivity per unit length; Indicates capacitance per unit length; It represents the imaginary unit.

[0164] Step C: Accumulate the grounding grid input impedances corresponding to different harmonic frequencies to obtain the total grounding grid impedance spectrum that reflects the change of grounding grid impedance with frequency.

[0165] The total impedance spectrum of a grounding grid can represent how the impedance of the grounding grid changes with frequency.

[0166] By selecting an appropriate accumulation method, the input impedance of the grounding grid at different harmonic frequencies is accumulated. The input impedances of the grounding grid corresponding to all harmonic frequencies are then combined to obtain a total impedance spectrum of the grounding grid that reflects its impedance characteristics across the entire frequency range. Optionally, vector accumulation can be used. The total impedance spectrum of the grounding grid can comprehensively and intuitively display the impedance changes of the grounding grid at different frequencies.

[0167] For example, the reactance spectra at each harmonic frequency are summed to obtain the total impedance spectrum of the grounding grid. for:

[0168]

[0169] in, Indicates frequency at frequency The discrete components at that point. Then, the total impedance spectrum of the grounding grid... After sorting, we can obtain:

[0170]

[0171] in, The load impedance; Let n be the nth frequency component, and ; Indicates wave impedance; Represents the propagation constant; This indicates the equivalent length of the grounding grid.

[0172] Correspondingly, by comparing the differences between the total impedance spectrum and the resistance spectrum of the grounding grid, and the differences between the total impedance spectrum and the reactance spectrum of the grounding grid, impedance characteristics that reflect the change of grounding grid impedance with frequency are obtained, including: by measuring the input impedance of the grounding grid and combining it with the propagation constant. The location dependence allows for the analytical comparison of the exponential decay term in the total impedance spectrum of the grounding grid. , and load reflection coefficient The changes in frequency are used to obtain the differences between the total impedance spectrum and the resistance spectrum of the grounding grid, and the differences between the total impedance spectrum and the reactance spectrum of the grounding grid. Furthermore, based on the differences between the total impedance spectrum and the resistance spectrum, and the differences between the total impedance spectrum and the reactance spectrum of the grounding grid, impedance characteristics reflecting the change of grounding grid impedance with frequency are obtained.

[0173] In one possible implementation, before injecting a bipolar square wave excitation signal into the grounding grid via a coupling device deployed in the grounding grid, the method further includes: amplifying the bipolar square wave signal to a preset intensity using a power amplifier to obtain the bipolar square wave excitation signal.

[0174] A bipolar square wave signal is the raw signal generated by a bipolar square wave signal generator. The power of a bipolar square wave signal is relatively low and cannot effectively excite the grounding grid. A bipolar square wave excitation signal, however, is amplified by a power amplifier, possessing sufficient power to effectively excite the grounding grid when injected into it.

[0175] The power amplifier can increase the intensity of the bipolar square wave signal generated by the bipolar square wave signal generator to a preset intensity, thereby obtaining a bipolar square wave excitation signal. This ensures that the bipolar square wave excitation signal, when injected into the grounding grid, will not be distorted due to insufficient power during transmission and excitation. Optionally, the preset intensity is determined based on the load level of the grounding grid.

[0176] Figure 5 This is a schematic diagram of the high-frequency response signal provided in the embodiments of this application, such as... Figure 5 As shown, the dashed line represents the ideal square wave of the bipolar square wave excitation signal; the thin solid line represents the high-frequency response signal; and the thick solid line represents the target high-frequency response signal, wherein:

[0177] The horizontal axis represents time, in units of... Seconds, with the vertical axis representing amplitude.

[0178] An ideal square wave represents the instantaneous switching of the amplitude of a bipolar square wave excitation signal between +1 and -1, without noise or distortion, representing the ideal state of the bipolar square wave excitation signal.

[0179] The high-frequency response signal represents a bipolar square wave excitation signal superimposed with high-frequency noise in actual measurements. The image of the high-frequency response signal exhibits blurred waveform edges and plateau fluctuations, reflecting the influence of sensor or environmental noise.

[0180] The target high-frequency response signal represents the signal after processing by the filter. Compared to the target high-frequency response signal, noise is suppressed, and the waveform of the target high-frequency response signal is closer to an ideal square wave.

[0181] Figure 6 This is a schematic diagram of impedance characteristics provided for an embodiment of this application. Figure 6 As shown, where;

[0182] Figure 6 A represents the amplitude characteristic diagram of the impedance characteristic provided in the embodiment of this application. The dashed line represents the theoretical amplitude value of the impedance characteristic; the thin solid line represents the measured amplitude value of the impedance characteristic; and the horizontal axis represents the frequency. Hertz; the vertical axis represents the impedance amplitude, in ohms.

[0183] The overall trend of the amplitude characteristic of impedance is that the reactance decreases as the frequency decreases.

[0184] When the frequency is less than At frequencies above 100 Hz, the impedance characteristic amplitude is relatively high, and the amplitude decreases rapidly with increasing frequency. When the frequency is greater than 100 Hz... At Hertz, the skin effect and capacitance effect are enhanced at high frequencies, leading to a decrease in the amplitude of the impedance characteristics.

[0185] The good overlap between the dashed and solid lines indicates that the theoretical value and the measured value of the impedance characteristic amplitude are close, demonstrating that the impedance characteristic evaluation method provided in this application can accurately predict the amplitude of the grounding grid impedance characteristic, thereby achieving an accurate evaluation of the grounding grid status.

[0186] Figure 6 B is the phase characteristic diagram of the impedance characteristic provided in the embodiment of this application. The dashed line represents the theoretical phase value of the impedance characteristic; the thin solid line represents the measured phase value of the impedance characteristic, and the horizontal axis represents the frequency. Hertz; the vertical axis represents the impedance phase, in degrees.

[0187] The overall trend of the amplitude characteristic of impedance is that the reactance increases with increasing frequency.

[0188] When the frequency is less than 3 At frequencies above 100 Hz, the phase angle of the impedance characteristic is negative, and the phase of the impedance characteristic increases slowly with increasing frequency. When the frequency is greater than 100 Hz... At Hertz, the phase angle of the impedance characteristic rises rapidly to near +90°.

[0189] The good overlap between the dashed and solid lines indicates that the theoretical value and the measured value of the impedance characteristic phase are close, demonstrating that the impedance characteristic evaluation method provided in this application can accurately predict the phase of the grounding grid impedance characteristics, thereby achieving an accurate evaluation of the grounding grid status.

[0190] Figure 7 This is a schematic diagram of the impedance characteristic evaluation device provided in an embodiment of this application. Figure 7 As shown, the impedance characteristic evaluation device 70 provided in this embodiment includes:

[0191] The acquisition module 701 is used to inject a bipolar square wave excitation signal into the grounding grid through a coupling device deployed in the grounding grid; and to acquire the high-frequency response signal generated by the grounding grid under the excitation of the bipolar square wave excitation signal through an acquisition device deployed in the grounding grid.

[0192] Processing module 702 is used to decompose the high-frequency response signal to obtain the resistance spectrum and reactance spectrum of the grounding grid. The resistance spectrum describes the change of the grounding grid's resistance and reactance with frequency. The reactance spectrum describes the change of the grounding grid's resistance with frequency. By comparing the differences between the total impedance spectrum and the resistance spectrum of the grounding grid, and the differences between the total impedance spectrum and the reactance spectrum of the grounding grid, the impedance characteristics that reflect the change of the grounding grid's impedance with frequency are obtained. The total impedance spectrum of the grounding grid is used to describe the resistance and impedance of the grounding grid at different frequencies when it is working normally.

[0193] In one possible implementation, the processing module 702 is specifically used for:

[0194] The high-frequency response signal is preprocessed to obtain the target high-frequency response signal. The data preprocessing includes noise removal, filtering, and signal calibration.

[0195] The high-frequency response signal of the target is decomposed to obtain the target resistance and target reactance of the grounding grid at different frequencies;

[0196] The resistance spectrum is obtained based on the target resistance of the grounding grid at different frequencies;

[0197] The reactance spectrum is obtained based on the target reactance of the grounding grid at different frequencies.

[0198] In one possible implementation, the processing module 702 is further configured to:

[0199] Fourier transform of the target's high-frequency response signal yields the frequency domain response signal and the time domain response signal corresponding to the target's high-frequency response signal;

[0200] Based on the frequency domain response signal and the time domain response signal, the grounding grid impedance is obtained through Ohm's law. The grounding grid impedance includes the impedance of the grounding grid at different frequencies.

[0201] By decomposing the grounding grid impedance, the target resistance and target reactance of the grounding grid at different frequencies can be obtained.

[0202] In one possible implementation, the acquisition device includes a high-frequency voltage sensor and a high-frequency current sensor, the high-frequency response signal includes a high-frequency voltage signal and a high-frequency current signal, and the acquisition module 701 is specifically used for:

[0203] The high-frequency voltage signal of the grounding grid under the excitation of a bipolar square wave excitation signal is collected by a high-frequency voltage sensor deployed in the grounding grid.

[0204] The high-frequency current signal of the grounding grid under the excitation of a bipolar square wave excitation signal is collected by a high-frequency current sensor deployed in the grounding grid.

[0205] In one possible implementation, the processing module 702 is further configured to obtain the total impedance spectrum of the grounding grid by:

[0206] Based on the load reflection coefficient, wave impedance, and propagation constant of the grounding grid, establish the two-dimensional input impedance relationship of the grounding grid;

[0207] Substituting the excitation function corresponding to the bipolar square wave excitation signal into the two-dimensional input impedance relationship, the grounding grid input impedance corresponding to different frequencies is obtained;

[0208] By summing up the input impedances of the grounding grid at different harmonic frequencies, a total impedance spectrum of the grounding grid that reflects the change of grounding grid impedance with frequency is obtained.

[0209] In one possible implementation, before injecting a bipolar square wave excitation signal into the grounding grid via a coupling device deployed in the grounding grid, the processing module 702 is further configured to:

[0210] The bipolar square wave signal is amplified to a preset intensity by a power amplifier to obtain the bipolar square wave excitation signal.

[0211] The impedance characteristic evaluation device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0212] Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 8 As shown, the electronic device 80 provided in this embodiment includes at least one processor 801 and a memory 802. Optionally, the device 80 further includes a communication component 803. The processor 801, memory 802, and communication component 803 are connected via a bus 804.

[0213] In a specific implementation, at least one processor 801 executes computer execution instructions stored in memory 802, causing at least one processor 801 to perform the above-described method.

[0214] The specific implementation process of processor 801 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0215] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0216] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0217] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings of this application's embodiments are not limited to only one bus or one type of bus.

[0218] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0219] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed, implement any of the methods described above.

[0220] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random-Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0221] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an application-specific integrated circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0222] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0223] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0224] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0225] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0226] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0227] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A method for evaluating impedance characteristics, characterized in that, include: A bipolar square wave excitation signal is injected into the grounding grid through a coupling device deployed in the grounding grid; The high-frequency response signal generated by the grounding grid under the excitation of the bipolar square wave excitation signal is acquired by the acquisition device deployed in the grounding grid. The high-frequency response signal is decomposed to obtain the resistance spectrum and reactance spectrum of the grounding grid; the resistance spectrum is used to describe the change of the grounding grid's resistance and reactance with frequency; the reactance spectrum is used to describe the change of the grounding grid's resistance with frequency. By comparing the differences between the total impedance spectrum of the grounding grid and the resistance spectrum, and the differences between the total impedance spectrum of the grounding grid and the reactance spectrum, impedance characteristics that reflect the change of grounding grid impedance with frequency are obtained. The total impedance spectrum of the grounding grid is used to describe the resistance and impedance of the grounding grid at different frequencies when it is working normally.

2. The method according to claim 1, characterized in that, The process of decomposing the high-frequency response signal to obtain the resistance spectrum and reactance spectrum of the grounding grid includes: The high-frequency response signal is preprocessed to obtain the target high-frequency response signal. The data preprocessing includes noise removal, filtering, and signal calibration. The high-frequency response signal of the target is decomposed to obtain the target resistance and target reactance of the grounding grid at different frequencies; The resistance spectrum is obtained based on the target resistance of the grounding grid at different frequencies; The reactance spectrum is obtained based on the target reactance of the grounding grid at different frequencies.

3. The method according to claim 2, characterized in that, The step of decomposing the target high-frequency response signal to obtain the target resistance and target reactance of the grounding grid at different frequencies includes: Fourier transform of the target high-frequency response signal yields the frequency domain response signal and time domain response signal corresponding to the target high-frequency response signal; Based on the frequency domain response signal and the time domain response signal, the grounding grid impedance is obtained through Ohm's law. The grounding grid impedance includes the impedance of the grounding grid at different frequencies. The grounding grid impedance is decomposed to obtain the target resistance and target reactance of the grounding grid at different frequencies.

4. The method according to claim 1, characterized in that, The acquisition device includes a high-frequency voltage sensor and a high-frequency current sensor. The high-frequency response signal includes a high-frequency voltage signal and a high-frequency current signal. The acquisition device, deployed in the grounding grid, acquires the high-frequency response signal of the grounding grid under the excitation of the bipolar square wave excitation signal, including: The high-frequency voltage sensor deployed in the grounding grid acquires the high-frequency voltage signal of the grounding grid under the excitation of the bipolar square wave excitation signal; The high-frequency current sensor deployed in the grounding grid collects the high-frequency current signal of the grounding grid under the excitation of the bipolar square wave excitation signal.

5. The method according to any one of claims 1-4, characterized in that, The total impedance spectrum of the grounding grid is obtained through the following methods: Based on the load reflection coefficient, wave impedance, and propagation constant of the grounding grid, establish the two-dimensional input impedance relationship of the grounding grid; Substituting the excitation function corresponding to the bipolar square wave excitation signal into the two-dimensional input impedance relationship, the grounding grid input impedance corresponding to different frequencies is obtained; The grounding grid input impedances corresponding to different harmonic frequencies are summed to obtain the total impedance spectrum of the grounding grid, which reflects the change of grounding grid impedance with frequency.

6. The method according to any one of claims 1-4, characterized in that, Before injecting a bipolar square wave excitation signal into the grounding grid via a coupling device deployed in the grounding grid, the method further includes: The bipolar square wave signal is amplified to a preset intensity by a power amplifier to obtain the bipolar square wave excitation signal.

7. An impedance characteristic evaluation device, characterized in that, include: The acquisition module is used to inject a bipolar square wave excitation signal into the grounding grid through a coupling device deployed in the grounding grid; The high-frequency response signal generated by the grounding grid under the excitation of the bipolar square wave excitation signal is acquired by the acquisition device deployed in the grounding grid. The processing module is used to decompose the high-frequency response signal to obtain the resistance spectrum and reactance spectrum of the grounding grid; the resistance spectrum is used to describe the change of the grounding grid's resistance and reactance with frequency; the reactance spectrum is used to describe the change of the grounding grid's resistance with frequency. By comparing the differences between the total impedance spectrum of the grounding grid and the resistance spectrum, and the differences between the total impedance spectrum of the grounding grid and the reactance spectrum, impedance characteristics that reflect the change of grounding grid impedance with frequency are obtained. The total impedance spectrum of the grounding grid is used to describe the resistance and impedance of the grounding grid at different frequencies when it is working normally.

8. An electronic device, characterized in that, include: Memory, processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory, causing the processor to perform the method as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed, are used to implement the method as described in any one of claims 1-6.

10. A computer program product, characterized in that, Includes a computer program, which, when executed, implements the method according to any one of claims 1-6.

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