Traveling wave head extraction method, system, electronic device and storage medium

Abstract

The present invention provides a traveling wave head extraction method, system, electronic device and storage medium, the method includes detecting an original traveling wave signal to obtain an original traveling wave signal; calculating the fast Fourier transform of the original traveling wave signal and the fast Fourier transform of the window function with a correction factor introduced to obtain the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency respectively; calculating the product of the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency according to the frequency sampling point, and calculating the discrete S transform; intercepting the traveling wave fault signal with time and amplitude as the x-axis and y-axis of the two-dimensional graph; based on the traveling wave undergoing discrete S transform, the amplitude difference of adjacent time nodes in the two-dimensional graph is used to simultaneously set the threshold to obtain the detection time of the first traveling wave head, so as to determine the mutation point position, and extract the traveling wave head. The present invention can detect various fault transients with very fast detection speed and sufficient sensitivity, and can also effectively reduce the influence of noise.

Description

Technical Field

[0001] The present invention relates to the technical field of high voltage direct current system fault location, and in particular to a traveling wave head extraction method, system, electronic equipment and storage medium. Background Art

[0002] When a power line fails, voltage and current traveling waves will be generated at the fault point and propagate along both ends of the line at a speed close to the speed of light. The traveling waves caused by the fault contain rich fault information. By rationally utilizing the fault information in the traveling wave signal, the fault can be accurately located. The accuracy of traveling wave head extraction directly affects the accuracy of the traveling wave positioning method.

[0003] In the prior art, the traditional traveling wave head detection method generally uses various filtering algorithms to denoise the traveling wave first, and then extracts the head. The classical filtering theory is based on the fact that the useful components and the components to be removed in the input signal each occupy different frequency bands. When the input signal is filtered, the components to be removed can be effectively removed. The traditional noise suppression method generally uses the low-pass filtering method. Although various low-pass filters can filter out white noise to a certain extent, they cannot effectively suppress pulse noise. However, during the propagation of the traveling wave, it may be interfered by various complex noises, especially pulse noise. Since the pulse noise is very similar to the mutation characteristics of the transient traveling wave signal, it must be reliably filtered out, otherwise it is likely to be confused with the mutation point of the traveling wave signal. Therefore, the traditional filtering algorithm often cannot achieve good results. After a high-voltage DC system fails, if the transient traveling wave head after the fault cannot be accurately captured and extracted, it will have a serious impact on the detection and location of the fault and cause more serious faults, causing economic losses and even inducing serious accidents such as electric shock and fire. Summary of the invention

[0004] Based on this, the purpose of the present invention is to provide a traveling wave head extraction method, system, electronic device and storage medium to solve the deficiencies in the above-mentioned prior art.

[0005] In a first aspect, the present invention provides a traveling wave head extraction method, the method comprising:

[0006] Detecting and collecting the original traveling wave signal to obtain the original traveling wave signal;

[0007] Calculating the fast Fourier transform of the original traveling wave signal and the fast Fourier transform of the window function with the correction factor introduced, so as to obtain the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency respectively;

[0008] Calculating the product of the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency according to the frequency sampling points, and calculating the inverse fast Fourier transform of the product to obtain a discrete S transform;

[0009] A two-dimensional graph of a traveling wave fault signal intercepted at a preset interception frequency with time and amplitude as the x-axis and y-axis;

[0010] Based on the traveling wave undergoing the discrete S transform, the amplitude difference between adjacent time nodes in the two-dimensional graph is used and a threshold is set to obtain the detection time of the first traveling wave head, so as to determine the mutation point position, and extract the traveling wave head based on the mutation point position.

[0011] Compared with the prior art, the beneficial effects of the present invention are: by introducing a correction factor in the window function, it is possible to extract the high-frequency spectrum while retaining the low-frequency information, so as to extract a clear and accurate traveling wave head, and by utilizing the amplitude difference of adjacent time nodes and setting a threshold at the same time to obtain the detection time of the first traveling wave head, and then determine the mutation point, so as to extract the traveling wave head, and be able to detect various fault transients with very fast detection speed and sufficient sensitivity. In addition, it can also effectively reduce the influence of noise.

[0012] Furthermore, the steps of calculating the fast Fourier transform of the original traveling wave signal and the fast Fourier transform of the window function with the correction factor introduced to obtain the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency include:

[0013] Calculating a fast Fourier transform of the original traveling wave signal to obtain a discrete form of the original traveling wave signal;

[0014] A correction factor is introduced into the window function, spectral information adjacent to the correction factor is extracted based on the window function, and a fast Fourier transform of the window function with the correction factor introduced is calculated to obtain a Gaussian function at an optimal frequency.

[0015] Furthermore, the calculation expression of the fast Fourier transform of the window function that calculates the correction factor is:

[0016] ;

[0017] represents the Gaussian function at the optimal frequency, represents the optimal recognition frequency of the window function, Indicates frequency, represents the base of the exponential function, represents the correction factor.

[0018] Furthermore, the window function is a Gaussian window, and the expression of the STFT corresponding to the Gaussian window is:

[0019] ;

[0020] In the formula, represents the short-time Fourier transform function, represents the short-time Fourier change corresponding to the Gaussian window, represents the width of the Gaussian window, Represents the position parameter that controls the Gaussian window on the time axis. represents the original traveling wave signal, Indicates time;

[0021] Wherein, the expression of the width of the Gaussian window is:

[0022] ;

[0023] In the formula, Represents the width function of the Gaussian window.

[0024] Furthermore, the step of intercepting the traveling wave fault signal at a preset interception frequency with time and amplitude as the x-axis and y-axis of the two-dimensional graph includes:

[0025] A two-dimensional graph with time and amplitude as x-axis and y-axis is intercepted in the three-dimensional graph representing the traveling wave fault signal with the correction factor as the interception frequency, wherein the x-axis, y-axis and z-axis in the three-dimensional graph represent frequency, time and amplitude respectively.

[0026] Furthermore, the expression for obtaining the detection time of the first row wave head by using the amplitude difference of adjacent time nodes in the two-dimensional graph and setting the threshold at the same time is:

[0027] ;

[0028] In the formula, represents the detection time of the first wave head, Indicates a time node. represents the amplitude, represents the threshold value, Indicated in The amplitude at the time node, Indicated in The amplitude at the time node, Indicates the number of sampling points.

[0029] In a second aspect, the present invention provides a traveling wave head extraction system, the system comprising:

[0030] A detection module, used for detecting and collecting the original traveling wave signal to obtain the original traveling wave signal;

[0031] A first calculation module is used to calculate the fast Fourier transform of the original traveling wave signal and the fast Fourier transform of the window function with the correction factor introduced, so as to obtain the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency respectively;

[0032] A second calculation module is used to calculate the discrete form of the original traveling wave signal and the product of the Gaussian function at the optimal frequency according to the frequency sampling points, and calculate the inverse fast Fourier transform of the product to obtain a discrete S transform;

[0033] An interception module is used to intercept the traveling wave fault signal at a preset interception frequency with time and amplitude as the x-axis and y-axis of the two-dimensional graph;

[0034] A detection module is set to obtain the detection time of the first traveling wave head based on the traveling wave undergoing the discrete S transform and using the amplitude difference of adjacent time nodes in the two-dimensional graph and setting a threshold at the same time, so as to determine the mutation point position, and extract the traveling wave head based on the mutation point position.

[0035] Furthermore, the first calculation module includes:

[0036] A calculation unit, used for calculating the fast Fourier transform of the original traveling wave signal to obtain a discrete form of the original traveling wave signal;

[0037] An introducing unit is used to introduce a correction factor into the window function, extract spectral information adjacent to the correction factor based on the window function, and calculate a fast Fourier transform of the window function with the correction factor introduced to obtain a Gaussian function at an optimal frequency.

[0038] In a third aspect, the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned traveling wave head extraction method when executing the computer program.

[0039] In a fourth aspect, the present invention further provides a storage medium having a computer program stored thereon, which implements the above-mentioned traveling wave head extraction method when executed by a processor. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a flow chart of the traveling wave head extraction method in the first embodiment of the present invention;

[0041] Figure 2 is the traveling wave response diagram during PP fault, Figure 2 (a) is the traveling wave position diagram when the transition resistance is 1Ω. Figure 2 (b) is the traveling wave position diagram when the transition resistance is 100Ω;

[0042] Figure 3 This is the traveling wave response diagram during PG fault. Figure 3 (a) is the traveling wave position diagram when the transition resistance is 1Ω. Figure 3(b) is the traveling wave position diagram when the transition resistance is 100Ω;

[0043] Figure 4 is a structural block diagram of a traveling wave head extraction system in a second embodiment of the present invention;

[0044] Figure 5 FIG. 4 is a schematic diagram of the hardware structure of an electronic device in a third embodiment of the present invention.

[0045] Description of main component symbols:

[0046] 10. Detection module; 20. First calculation module; 30. Second calculation module; 40. Interception module; 50. Setting detection module;

[0047] 60. Bus; 61. Processor; 62. Memory; 63. Communication interface.

[0048] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0049] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0050] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0052] Embodiment 1

[0053] See also Figure 1 , which shows a traveling wave head extraction method in a first embodiment of the present invention, the method comprises steps S1 to S5:

[0054] S1, detecting and collecting the original traveling wave signal to obtain the original traveling wave signal;

[0055] It needs to be explained that the traveling wave generated when the line fault occurs can be decomposed into zero mode and line mode components. When using any of the two mode components or any distance measurement method to perform traveling wave fault distance measurement, the wave conduction velocity must be measured, and the location of the fault point is determined by the relationship between wave velocity and time. The propagation speed of each mode component is not unique on the transmission line. As one of the important factors affecting the line traveling wave fault distance measurement, the wave velocity is determined by the earth resistivity distribution and the structure of the transmission line. In addition, due to the influence of climatic factors, the uneven distribution of line corona affects its distributed capacitance. Changes in distributed inductance and distributed capacitance will affect the propagation of the zero mode component and line mode component of the traveling wave.

[0056] In this embodiment, the voltage traveling wave is used for traveling wave fault location. The calculation expressions of the 0-mode and 1-mode of the voltage are:

[0057] ;

[0058] In the formula, Represents the zero-mode voltage between the DC line and the ground, Indicates the 1-mode voltage between the positive and negative electrodes, , Respectively represent the positive electrode voltage and the negative electrode voltage. In this embodiment, To estimate the fault location.

[0059] As the voltage wave on the transmission line moves forward, the distributed capacitance of the line is continuously charged and generates a current wave that accompanies the forward movement. The relationship between the voltage wave and the current wave can be described by the wave impedance Z (also called characteristic impedance). The expression of the transmission line wave impedance is:

[0060] ;

[0061] In the formula, represents the wave impedance, represents the inductance of the transmission line, Represents the capacitance of the transmission line;

[0062] Forward voltage U + , current wave I + The relationship expression that should be satisfied is:

[0063] ;

[0064] For the reverse voltage wave U — , current waveI — The relationship is:

[0065] ;

[0066] Therefore, it can be known that the forward voltage wave has the same polarity as the current wave, and the reverse voltage wave has the opposite polarity as the current wave.

[0067] S2, calculating the fast Fourier transform of the original traveling wave signal and the fast Fourier transform of the window function with the correction factor introduced, so as to obtain the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency respectively;

[0068] Specifically, the step S2 includes steps S21 to S22:

[0069] S21, calculating the fast Fourier transform of the original traveling wave signal to obtain a discrete form of the original traveling wave signal;

[0070] It can be understood that by calculating the fast Fourier transform of the original signal, the discrete form of the original traveling wave signal can be obtained, and by extension, the discrete form of the original traveling wave signal with the frequency sampling points added can be obtained. ,in, Indicates the number of frequency sampling points;

[0071] S22, introducing a correction factor into the window function, extracting spectral information adjacent to the correction factor based on the window function, and calculating a fast Fourier transform of the window function into which the correction factor is introduced, so as to obtain a Gaussian function at an optimal frequency;

[0072] It is understandable that the fault transient causes obvious spectrum leakage in the low frequency band, and the time resolution of the low frequency band is poor, so it is difficult to detect the accurate fault time from the original ST spectrum. In order to clearly observe the high frequency information with high time resolution, the correction factor ν is introduced into the Gaussian function in the subsequent steps of the ST calculation method. When setting the factor, avoid low frequency band leakage and extract the high frequency spectrum while retaining the low frequency spectrum information. The fast Fourier transform of the window function is calculated, and the expression is:

[0073] ;

[0074] In the formula, Represents the window function, so we can get:

[0075] ;

[0076] In the formula, represents the Gaussian function at the optimal frequency, represents the optimal recognition frequency of the window function, Indicates frequency, represents the base of the exponential function, represents the correction factor.

[0077] It needs to be explained that the weighted effect of the Gaussian function is used to extract Nearby spectral information. The value should not be too low to obtain the required time resolution, nor too high to suppress the low frequency band. Spectrum information.

[0078] Furthermore, in this embodiment, the window function is a Gaussian window, and the expression of the STFT corresponding to the Gaussian window is:

[0079] ;

[0080] In the formula, represents the short-time Fourier transform function, represents the short-time Fourier change corresponding to the Gaussian window, represents the width of the Gaussian window, Represents the position parameter that controls the Gaussian window on the time axis. represents the original traveling wave signal, Indicates time;

[0081] Wherein, the expression of the width of the Gaussian window is:

[0082] ;

[0083] In the formula, Represents the width function of the Gaussian window.

[0084] S3, calculating the product of the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency according to the frequency sampling points, and calculating the inverse fast Fourier transform of the product to obtain a discrete S transform;

[0085] It needs to be explained that the time-frequency resolution of the discrete S transform depends on the change of frequency. It is directly related to the STFT and is expressed as:

[0086] ;

[0087] In the formula, represents the short-time Fourier transform function, Represents the position parameter that controls the Gaussian window on the time axis. represents the window function, since exist Time The weighted effect of Nearby is kept, away is suppressed. Therefore, The frequency distribution of can be expressed as .

[0088] In this embodiment, the window function is a Gaussian window, so in the continuous domain, the expression of ST in which the window width is inversely proportional to the signal frequency is obtained as follows:

[0089] ;

[0090] In the formula, Represents the S-transformation function, ST is also written as Fourier spectrum Operation, we can get:

[0091] ;

[0092] In the formula, Represents the best recognition frequency of the window function, → , → , → , is the sampling period, Represents the position parameter of the Gaussian window on the time axis t and the corresponding parameter of the discretization, represents the parameter corresponding to the frequency discretization, represents the parameter corresponding to the discretization of the optimal recognition frequency, then the discrete ST is obtained as:

[0093]

[0094] In the formula, represents the number of frequency sampling points, Indicates the corresponding frequency point.

[0095] S4, intercepting the traveling wave fault signal at a preset interception frequency to form a two-dimensional graph with time and amplitude as the x-axis and y-axis;

[0096] Specifically, the step S4 includes step S41:

[0097] S41, using the correction factor as the interception frequency to intercept a two-dimensional graph with time and amplitude as the x-axis and y-axis in the three-dimensional graph representing the traveling wave fault signal, wherein the x-axis, y-axis, and z-axis in the three-dimensional graph represent frequency, time, and amplitude, respectively.

[0098] S5, based on the traveling wave undergoing the discrete S transform, the amplitude difference between adjacent time nodes in the two-dimensional graph is used and a threshold is set at the same time to obtain the detection time of the first traveling wave head, so as to determine the mutation point position, and extract the traveling wave head based on the mutation point position;

[0099] It needs to be explained that after the traveling wave undergoes discrete ST, the amplitude difference between adjacent time nodes can be used to set the threshold at the same time to obtain the detection time of the first traveling wave head, and then determine the position of the mutation point. The expression for determining the position of the mutation point is:

[0100] ;

[0101] In the formula, represents the detection time of the first wave head, Indicates a time node. represents the amplitude, represents the threshold value, Indicated in The amplitude at the time node, Indicated in The amplitude at the time node, Indicates the number of sampling points.

[0102] It is worth noting that a PP fault indicates a short circuit fault between the positive and negative poles of a DC line, while a PG fault indicates a short circuit fault between the positive or negative pole and the ground, and the DC fault condition varies with the fault distance and fault resistance. Figure 2 As shown in Figure 2, the traveling wave response diagram during the PP fault period under different conditions before and after the arrival of the traveling wave is compared. The fault location is 10 km away. Figure 2 The transition resistance in (a) is 1Ω, Figure 2 The transition resistance in (b) is 100Ω.

[0103] like Figure 3 As shown in the figure, the traveling wave response diagram during the PG fault period under different conditions before and after the arrival of the traveling wave is compared. The fault location is 10 km away. Figure 3 The transition resistance in (a) is 1Ω, Figure 3 The transition resistance in (b) is 100Ω.

[0104] In summary, the traveling wave head extraction method in the above embodiment of the present invention introduces a correction factor in the window function, thereby extracting the high-frequency spectrum while retaining the low-frequency information, so as to extract a clear and accurate traveling wave head, and obtains the detection time of the first traveling wave head by utilizing the amplitude difference between adjacent time nodes and setting the threshold, and then determines the mutation point, so as to extract the traveling wave head, and can detect various fault transients with very fast detection speed and sufficient sensitivity. In addition, it can also effectively reduce the influence of noise.

[0105] Embodiment 2

[0106] See also Figure 4 , shown is a traveling wave head extraction system in a second embodiment of the present invention, the system comprising:

[0107] The detection module 10 is used to detect and collect the original traveling wave signal to obtain the original traveling wave signal;

[0108] A first calculation module 20 is used to calculate the fast Fourier transform of the original traveling wave signal and the fast Fourier transform of the window function with the correction factor introduced, so as to obtain the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency respectively;

[0109] A second calculation module 30 is used to calculate the product of the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency according to the frequency sampling points, and calculate the inverse fast Fourier transform of the product to obtain a discrete S transform;

[0110] An interception module 40 is used to intercept the traveling wave fault signal at a preset interception frequency with time and amplitude as the x-axis and y-axis of the two-dimensional graph;

[0111] A detection module 50 is set, which is used to obtain the detection time of the first traveling wave head based on the traveling wave undergoing the discrete S transform and using the amplitude difference of adjacent time nodes in the two-dimensional graph and setting a threshold at the same time, so as to determine the mutation point position, and extract the traveling wave head based on the mutation point position;

[0112] The expression for obtaining the detection time of the first row wave head by using the amplitude difference of adjacent time nodes in the two-dimensional graph and setting the threshold at the same time is:

[0113] ;

[0114] In the formula, represents the detection time of the first wave head, Indicates a time node. represents the amplitude, represents the threshold value, Indicated in The amplitude at the time node, Indicated in The amplitude at the time node, Indicates the number of sampling points.

[0115] In some optional embodiments, the first calculation module 20 includes:

[0116] A calculation unit, used for calculating the fast Fourier transform of the original traveling wave signal to obtain a discrete form of the original traveling wave signal;

[0117] An introducing unit, used for introducing a correction factor into the window function, extracting spectral information adjacent to the correction factor based on the window function, and calculating a fast Fourier transform of the window function with the correction factor introduced, so as to obtain a Gaussian function at an optimal frequency;

[0118] The calculation expression of the fast Fourier transform of the window function introducing the correction factor is:

[0119] ;

[0120] In the formula, represents the Gaussian function at the optimal frequency, represents the optimal recognition frequency of the window function, Indicates frequency, represents the base of the exponential function, represents the correction factor;

[0121] The window function is a Gaussian window, and the expression of the STFT corresponding to the Gaussian window is:

[0122] ;

[0123] In the formula, represents the short-time Fourier transform function, represents the short-time Fourier change corresponding to the Gaussian window, represents the width of the Gaussian window, Represents the position parameter that controls the Gaussian window on the time axis. represents the original traveling wave signal, Indicates time;

[0124] Wherein, the expression of the width of the Gaussian window is:

[0125] ;

[0126] In the formula, Represents the width function of the Gaussian window.

[0127] In some optional embodiments, the interception module 40 includes:

[0128] The interception unit is used to intercept a two-dimensional graph with time and amplitude as the x-axis and y-axis in the three-dimensional graph representing the traveling wave fault signal with the correction factor as the interception frequency, wherein the x-axis, y-axis and z-axis in the three-dimensional graph represent frequency, time and amplitude respectively.

[0129] The functions or operation steps implemented when the above modules and units are executed are generally the same as those in the above method embodiments, and will not be repeated here.

[0130] The traveling wave head extraction system provided in the embodiment of the present invention has the same implementation principle and technical effects as those of the aforementioned method embodiment. For the sake of brief description, for matters not mentioned in the system embodiment, reference may be made to the corresponding contents in the aforementioned method embodiment.

[0131] Embodiment 3

[0132] The present invention also provides an electronic device, see Figure 5 , which is a schematic diagram of the hardware structure of the electronic device in the third embodiment of the present invention.

[0133] The electronic device may include a processor 61 and a memory 62 storing computer program instructions.

[0134] Specifically, the processor 61 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the present application.

[0135] Among them, the memory 62 may include a large-capacity memory for data or instructions. For example, but not limitation, the memory 62 may include a hard disk drive (HDD), a floppy disk drive, a solid-state drive (SSD), a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, the memory 62 may include a removable or non-removable (or fixed) medium. In appropriate cases, the memory 62 may be inside or outside the data processing device. In a specific embodiment, the memory 62 is a non-volatile memory. In a specific embodiment, the memory 62 includes a read-only memory (ROM) and a random access memory (RAM). Where appropriate, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically alterable ROM (EAROM) or a flash memory (FLASH), or a combination of two or more of these. Under appropriate circumstances, the RAM can be a static random access memory (SRAM) or a dynamic random access memory (DRAM), wherein the DRAM can be a fast page mode dynamic random access memory (FPMDRAM), an extended data output dynamic random access memory (EDODRAM), a synchronous dynamic random access memory (SDRAM), etc.

[0136] The memory 62 may be used to store or cache various data files required for processing and / or communication, as well as possible computer program instructions executed by the processor 61 .

[0137] The processor 61 implements the traveling wave head extraction method of the first embodiment by reading and executing the computer program instructions stored in the memory 62 .

[0138] In some of the embodiments, the electronic device may further include a communication interface 63 and a bus 60. Figure 5 As shown, the processor 61, the memory 62, and the communication interface 63 are connected via a bus 60 and communicate with each other.

[0139] The communication interface 63 is used to realize the communication between the modules, devices, units and / or equipment in the present application. The communication interface 63 can also realize data communication with other components such as: external devices, image / data acquisition equipment, databases, external storage and image / data processing workstations.

[0140] The bus 60 includes hardware, software or both, and couples the components of the device to each other. The bus 60 includes but is not limited to at least one of the following: a data bus, an address bus, a control bus, an expansion bus, and a local bus. By way of example and not limitation, bus 60 may include an Accelerated Graphics Port (AGP) or other graphics bus, an Extended Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hyper Transport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an InfiniBand interconnect, a Low Pin Count (LPC) bus, a memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local Bus (VLB) bus, or other suitable buses or a combination of two or more of these. Where appropriate, bus 60 may include one or more buses. Although this application describes and illustrates a particular bus, this application contemplates any suitable bus or interconnect.

[0141] The electronic device can acquire the traveling wave head extraction system and execute the traveling wave head extraction method of the first embodiment.

[0142] In addition, in combination with the traveling wave head extraction method in the above embodiment 1, the present application can provide a storage medium for implementation. The storage medium stores computer program instructions; when the computer program instructions are executed by the processor, the traveling wave head extraction method in the above embodiment 1 is implemented.

[0143] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0144] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A traveling wave head extraction method, characterized in that: The method comprises: Detecting and collecting the original traveling wave signal to obtain the original traveling wave signal; Calculating the fast Fourier transform of the original traveling wave signal to obtain a discrete form of the original traveling wave signal; introducing a correction factor into a window function, extracting spectral information adjacent to the correction factor based on the window function, and calculating the fast Fourier transform of the window function with the correction factor introduced to obtain a Gaussian function at an optimal frequency; Calculating the product of the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency according to the frequency sampling points, and calculating the inverse fast Fourier transform of the product to obtain a discrete S transform; A two-dimensional graph of a traveling wave fault signal intercepted at a preset interception frequency with time and amplitude as the x-axis and y-axis; Based on the traveling wave undergoing the discrete S transform, the amplitude difference between adjacent time nodes in the two-dimensional graph is used and a threshold is set to obtain the detection time of the first traveling wave head, so as to determine the mutation point position, and extract the traveling wave head based on the mutation point position.

2. The traveling wave head extraction method according to claim 1, characterized in that: The calculation expression of the fast Fourier transform of the window function introducing the correction factor is: ； In the formula, represents the Gaussian function at the optimal frequency, represents the optimal recognition frequency of the window function, Indicates frequency, represents the base of the exponential function, represents the correction factor.

3. The traveling wave head extraction method according to claim 2, characterized in that: The window function is a Gaussian window, and the expression of the STFT corresponding to the Gaussian window is: ； In the formula, represents the short-time Fourier transform function, represents the short-time Fourier change corresponding to the Gaussian window, represents the width of the Gaussian window, Represents the position parameter that controls the Gaussian window on the time axis. represents the original traveling wave signal, Indicates time; Wherein, the expression of the width of the Gaussian window is: ； In the formula, Represents the width function of the Gaussian window.

4. The traveling wave head extraction method according to claim 1, characterized in that: The step of intercepting the traveling wave fault signal with a preset interception frequency and taking the time and amplitude as the x-axis and the y-axis as the two-dimensional graph comprises: A two-dimensional graph with time and amplitude as x-axis and y-axis is intercepted in the three-dimensional graph representing the traveling wave fault signal with the correction factor as the interception frequency, wherein the x-axis, y-axis and z-axis in the three-dimensional graph represent frequency, time and amplitude respectively.

5. The traveling wave head extraction method according to claim 1, characterized in that: The expression for obtaining the detection time of the first row wave head by using the amplitude difference of adjacent time nodes in the two-dimensional graph and setting the threshold at the same time is: ； In the formula, represents the detection time of the first wave head, Indicates a time node. represents the amplitude, represents the threshold value, Indicated in The amplitude at the time node, Indicated in The amplitude at the time node, Indicates the number of sampling points.

6. A traveling wave head extraction system, characterized in that: The system comprises: A detection module, used for detecting and collecting the original traveling wave signal to obtain the original traveling wave signal; A first calculation module is used to calculate the fast Fourier transform of the original traveling wave signal to obtain a discrete form of the original traveling wave signal, and to introduce a correction factor into a window function, extract spectral information adjacent to the correction factor based on the window function, and calculate the fast Fourier transform of the window function with the correction factor introduced to obtain a Gaussian function at an optimal frequency; A second calculation module is used to calculate the product of the discrete form of the original traveling wave signal and the Gaussian function at the optimal frequency according to the frequency sampling points, and calculate the inverse fast Fourier transform of the product to obtain a discrete S transform; An interception module is used to intercept the traveling wave fault signal at a preset interception frequency with time and amplitude as the x-axis and y-axis of the two-dimensional graph; A detection module is set to obtain the detection time of the first traveling wave head based on the traveling wave undergoing the discrete S transform and using the amplitude difference of adjacent time nodes in the two-dimensional graph and setting a threshold at the same time, so as to determine the mutation point position, and extract the traveling wave head based on the mutation point position.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the traveling wave head extraction method according to any one of claims 1 to 5 is implemented.

8. A storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the traveling wave head extraction method according to any one of claims 1 to 5 is implemented.

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