Transformer winding axial displacement fault diagnosis method and related equipment

Abstract

The embodiment of the invention discloses a transformer winding axial displacement fault diagnosis method and related equipment, and the method comprises the steps: carrying out the feature extraction of a first amplitude-frequency characteristic curve of a transformer without winding fault, and obtaining a first waveform feature reference value; the method for diagnosing the winding fault by comparing the first waveform characteristic reference value with the second waveform characteristic reference value does not need manual judgment, and has the advantages of being fast, efficient and accurate in diagnosis of the winding fault and the like, and the method for diagnosing the winding fault by comparing the first waveform characteristic reference value with the second waveform characteristic reference value is provided. Therefore, the fault diagnosis accuracy of the transformer winding is improved, and the safe and stable operation of the transformer can be ensured to a greater extent.

Description

[Technical field]

[0001] The present invention relates to the technical field of winding fault diagnosis, and in particular to a transformer winding axial displacement fault diagnosis method and related equipment. [Background technology]

[0002] As one of the most important components in the structure of power transformers, transformer windings are not only the path for current flow, but also the main carrier of magnetic energy coupling. By adjusting the number of turns of the primary and secondary windings, the transformation of different voltage levels can be achieved, and they carry the important task of power conversion. On the other hand, the windings are not only complex in structure, but also located inside the transformer and cannot be directly observed and tested. In addition, they are faced with problems such as long-term operation, overload, and material aging, and their faults are often difficult to detect. Once a winding fails, it may cause a short circuit or partial discharge inside the transformer, resulting in damage to the transformer, and even fire or explosion, threatening personal and property safety. At the same time, power outages will affect users' normal production and living electricity consumption, causing serious economic losses and social impacts. It can be seen that the fault diagnosis of transformer windings is of vital importance to ensure the safe operation of the power system.

[0003] The electrical parameters of transformer windings in the equivalent network are closely related to the geometric structure, relative position, and insulating medium of the windings. When the windings fail in different situations, the electrical parameters in the equivalent network will change accordingly. Since the frequency response characteristic curves of the windings under different fault conditions overlap and change in a complex and diverse manner, experienced personnel are often required in current practical applications to judge the fault conditions of the windings based on the degree of deviation of the characteristic curves and the law of change of the resonance point. This manual judgment method is inefficient and inaccurate, and cannot guarantee the safe and stable operation of the transformer. [Summary of the invention]

[0004] In view of this, the present invention provides a transformer winding axial displacement fault diagnosis method and related equipment.

[0005] The specific technical scheme of the first embodiment of the present invention is: a transformer winding axial displacement fault diagnosis method, the method comprising: injecting a first excitation signal of different frequencies into a first transformer and a second transformer, obtaining a first response signal output by the first transformer and a second response signal output by the second transformer; the first transformer is a transformer without a winding fault, and the second transformer is a transformer with a winding fault; obtaining a first amplitude-frequency characteristic curve of the first transformer according to the first excitation signal and the first response signal; obtaining a second amplitude-frequency characteristic curve of the second transformer according to the first excitation signal and the second response signal; obtaining a first sampling frequency point total number and a first amplitude-frequency characteristic curve of the first amplitude-frequency characteristic curve according to the total number of sampling frequency points and the first amplitude-frequency characteristic curve of the first amplitude-frequency characteristic curve The first waveform characteristic reference value of the first transformer is obtained by the first amplitude of the frequency point in the curve; the first waveform characteristic reference value includes the first amplitude root mean square, the first amplitude absolute average, the first amplitude kurtosis, the first amplitude peak factor and the first amplitude margin factor; the second waveform characteristic reference value of the second transformer is obtained according to the total number of the second sampling frequency points of the second amplitude-frequency characteristic curve and the second amplitude of the frequency point in the second amplitude-frequency characteristic curve; the second waveform characteristic reference value includes the second amplitude root mean square, the second amplitude absolute average, the second amplitude kurtosis, the second amplitude peak factor and the second amplitude margin factor; the axial displacement fault diagnosis result of the winding of the second transformer is obtained according to the first waveform characteristic reference value and the second waveform characteristic reference value.

[0006] Preferably, the axial displacement fault diagnosis result of the second transformer is obtained according to the first waveform characteristic reference value and the second waveform characteristic reference value, including: if the second amplitude root mean square is greater than the first amplitude root mean square, the second amplitude absolute average value is greater than the first amplitude absolute average value, the second amplitude peak factor is less than the first amplitude peak factor and the second amplitude margin factor is less than the first amplitude margin factor, then an axial displacement fault occurs in the winding of the second transformer.

[0007] Preferably, the method further includes: the larger the value of the second amplitude root mean square or the second amplitude absolute average value is, the more serious the degree of the axial displacement fault of the second transformer winding is.

[0008] Preferably, the method further includes: the smaller the value of the second amplitude peak factor or the second amplitude margin factor is, the more serious the axial displacement fault of the second transformer winding is.

[0009] Preferably, the method also includes: when an axial displacement fault occurs in the second transformer winding, if the second amplitude kurtosis is smaller than the first amplitude kurtosis, an axial displacement fault occurs in a preset upper area of ​​the winding; if the second amplitude kurtosis is larger than the first amplitude kurtosis, an axial displacement fault occurs in a preset middle area and a preset lower area of ​​the winding.

[0010] Preferably, the first amplitude root mean square, the first amplitude absolute average and the first amplitude peak factor are obtained using the following formula:

[0011]

[0012] Wherein, RMS is the first amplitude root mean square, AM is the first amplitude absolute average, CF is the first amplitude peak factor, N is the total number of sampling frequency points, Y(i) is the amplitude corresponding to the frequency point of the first amplitude-frequency characteristic curve when the frequency is i, and Y max (i) is the maximum amplitude value in the first amplitude-frequency characteristic curve.

[0013] Preferably, the first amplitude kurtosis and the second amplitude margin factor are obtained using the following formula:

[0014]

[0015] Wherein, Ku is the first amplitude kurtosis, MF is the second amplitude margin factor, N is the total number of sampling frequency points, Y(i) is the amplitude corresponding to the frequency point of the first amplitude-frequency characteristic curve when the frequency is i, and Y max (i) is the maximum amplitude value in the first amplitude-frequency characteristic curve, is the average amplitude value of the first amplitude-frequency characteristic curve.

[0016] The specific technical scheme of the second embodiment of the present invention is: a transformer winding axial displacement fault diagnosis system, the system comprising: a response signal acquisition module, a first amplitude-frequency characteristic curve acquisition module, a second amplitude-frequency characteristic curve acquisition module, a first characteristic reference value acquisition module, a second characteristic reference value acquisition module and a diagnosis module; the response signal acquisition module is used to inject a first excitation signal of different frequencies into a first transformer and a second transformer, and obtain a first response signal output by the first transformer and a second response signal output by the second transformer; the first transformer is a transformer without a winding fault, and the second transformer is a transformer with a winding fault; the first amplitude-frequency characteristic curve acquisition module is used to obtain a first amplitude-frequency characteristic curve of the first transformer according to the first excitation signal and the first response signal; the second amplitude-frequency characteristic curve acquisition module is used to obtain a second amplitude-frequency characteristic curve of the second transformer according to the first excitation signal and the second response signal frequency characteristic curve; the first characteristic reference value acquisition module is used to obtain the first waveform characteristic reference value of the first transformer according to the total number of first sampling frequency points of the first amplitude-frequency characteristic curve and the first amplitude of the frequency point in the first amplitude-frequency characteristic curve; the first waveform characteristic reference value includes a first amplitude root mean square, a first amplitude absolute average value, a first amplitude kurtosis, a first amplitude peak factor and a first amplitude margin factor; the second characteristic reference value acquisition module is used to obtain the second waveform characteristic reference value of the second transformer according to the total number of second sampling frequency points of the second amplitude-frequency characteristic curve and the second amplitude of the frequency point in the second amplitude-frequency characteristic curve; the second waveform characteristic reference value includes a second amplitude root mean square, a second amplitude absolute average value, a second amplitude kurtosis, a second amplitude peak factor and a second amplitude margin factor; the diagnosis module is used to obtain the axial displacement fault diagnosis result of the second transformer winding according to the first waveform characteristic reference value and the second waveform characteristic reference value.

[0017] The specific technical solution of the third embodiment of the present invention is: a transformer winding axial displacement fault diagnosis device, including a memory and a processor, the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method described in any one of the first embodiments of the present application.

[0018] The specific technical solution of the fourth embodiment of the present invention is: a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to perform the steps of the method described in any one of the first embodiments of the present application.

[0019] Implementing the embodiments of the present invention will have the following beneficial effects:

[0020] The present invention obtains a first waveform characteristic reference value by performing feature extraction on the first amplitude-frequency characteristic curve of the transformer without winding fault, and obtains a second waveform characteristic reference value by performing feature extraction on the second amplitude-frequency characteristic curve of the transformer with winding fault. The method for diagnosing winding fault by comparing the first waveform characteristic reference value with the second waveform characteristic reference value does not require human judgment and has the advantages of fast, efficient and accurate diagnosis of winding faults, thereby improving the accuracy of transformer winding fault diagnosis and can ensure the safe and stable operation of the transformer to a greater extent.

Brief Description of the Drawings

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A flowchart of the steps of a transformer winding axial displacement fault diagnosis method;

[0023] Figure 2 It is the structural diagram of the winding fault test platform;

[0024] Figure 3 It is a structural schematic diagram of a transformer winding axial displacement fault diagnosis system;

[0025] Figure 4 It is a diagram of the internal structure of a computer device;

[0026] Among them, 201, computer; 202, signal generator; 203, first circuit breaker; 204, second circuit breaker; 205, third circuit breaker; 206, capacitance sensor; 207, voltage transformer; 208, station transformer; 209, protection resistor; 210, low voltage bushing; 211, high voltage bushing; 212, test transformer; 213, iron core; 214, low voltage winding; 215, high voltage winding; 301, response signal acquisition module; 302, first amplitude-frequency characteristic curve acquisition module; 303, second amplitude-frequency characteristic curve acquisition module; 304, first characteristic reference value acquisition module; 305, second characteristic reference value acquisition module; 306, diagnosis module. [Specific implementation method]

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0028] The terms "first", "second", etc. in the specification, claims and drawings of this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or modules is not limited to the listed steps or modules, but optionally includes steps or modules that are not listed, or optionally includes other steps or modules that are inherent to these processes, methods, products or devices.

[0029] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0030] See also Figure 1 , is a flowchart of a method for diagnosing transformer winding axial displacement faults in the first embodiment of the present application, so as to ensure the safe and stable operation of the transformer, the method comprising:

[0031] Step 101: injecting first excitation signals of different frequencies into a first transformer and a second transformer, and obtaining a first response signal output by the first transformer and a second response signal output by the second transformer; the first transformer is a transformer without winding fault, and the second transformer is a transformer with winding fault;

[0032] Step 102: obtaining a first amplitude-frequency characteristic curve of the first transformer according to the first excitation signal and the first response signal;

[0033] Step 103: obtaining a second amplitude-frequency characteristic curve of the second transformer according to the first excitation signal and the second response signal;

[0034] Step 104: obtaining a first waveform characteristic reference value of the first transformer according to the total number of first sampling frequency points of the first amplitude-frequency characteristic curve and the first amplitude of the frequency point in the first amplitude-frequency characteristic curve; the first waveform characteristic reference value includes a first amplitude root mean square value, a first amplitude absolute average value, a first amplitude kurtosis, a first amplitude peak factor and a first amplitude margin factor;

[0035] Step 105: obtaining a second waveform characteristic reference value of the second transformer according to the total number of second sampling frequency points of the second amplitude-frequency characteristic curve and the second amplitude of the frequency point in the second amplitude-frequency characteristic curve; the second waveform characteristic reference value includes a second amplitude root mean square, a second amplitude absolute average, a second amplitude kurtosis, a second amplitude peak factor, and a second amplitude margin factor;

[0036] Step 106: Obtain an axial displacement fault diagnosis result of the second transformer winding according to the first waveform characteristic reference value and the second waveform characteristic reference value.

[0037] Specifically, the response signal is obtained in the winding fault test platform. The structural diagram of the winding fault test platform can be found in Figure 2 The winding fault test platform mainly includes: a computer 201, a signal generator 202, a first circuit breaker 203 connected to a capacitor sensor 206, a second circuit breaker 204 connected to a voltage transformer 207, a third circuit breaker 205 connected to a station transformer 208, a protective resistor 209, a low-voltage bushing 210, a high-voltage bushing 211, a test transformer 212, an iron core 213, a low-voltage winding 214 and a high-voltage winding 215; the computer 201 cooperates with the signal generator 202 to generate an excitation signal, and the signal is transmitted through the first circuit breaker 20 3. The second circuit breaker 204 and the third circuit breaker 205 pass through the capacitor sensor 206, the voltage transformer 207 and the station transformer 208 in turn to reach the low-voltage bushing 210, and then flow into the low-voltage winding 214 and the high-voltage winding 215 of the test transformer 212. Finally, the response signal received at the high-voltage bushing 211 is transmitted back to the computer 201. After technical processing, the amplitude-frequency characteristic curve of the normal transformer winding under the condition that the non-excitation signal is input from the capacitor sensor 206, the voltage transformer 207 and the station transformer 208 side can be obtained in turn. After setting corresponding axial displacement faults on the low-voltage winding 214 and the high-voltage winding 215, the test steps are repeated to obtain the amplitude-frequency characteristic curve of the second transformer under a fault condition, and at the same time, obtain the amplitude-frequency characteristic curve of the first transformer without a winding fault. The first waveform characteristic reference value is obtained by extracting features from the first amplitude-frequency characteristic curve of the transformer without a winding fault, and the second waveform characteristic reference value is obtained by extracting features from the second amplitude-frequency characteristic curve of the transformer with a winding fault. The winding fault is diagnosed by comparing the first waveform characteristic reference value with the second waveform characteristic reference value.

[0038] The method in this embodiment obtains a first waveform characteristic reference value by performing feature extraction on the first amplitude-frequency characteristic curve of the transformer without winding fault, and obtains a second waveform characteristic reference value by performing feature extraction on the second amplitude-frequency characteristic curve of the transformer with winding fault. The method of diagnosing winding fault by comparing the first waveform characteristic reference value with the second waveform characteristic reference value does not require human judgment and has the advantages of fast, efficient and accurate diagnosis of winding faults, thereby improving the accuracy of transformer winding fault diagnosis and can ensure the safe and stable operation of the transformer to a greater extent.

[0039] In a specific embodiment, for each frequency of the input excitation signal, the ratio of the steady-state amplitude of the output response signal to the amplitude of the input excitation signal is calculated, and this ratio is the amplitude-frequency characteristic value at this frequency. All input frequencies and their corresponding amplitude-frequency characteristic values ​​are plotted on a coordinate system. The horizontal axis represents the frequency of the input signal, and the vertical axis represents the amplitude-frequency characteristic value (i.e., the ratio of the output amplitude to the input amplitude). Connect these points to form a smooth curve, which is the amplitude-frequency characteristic curve.

[0040] In a specific embodiment, the first amplitude root mean square, the first amplitude absolute average value and the first amplitude peak factor are obtained using the following formula:

[0041]

[0042] Wherein, RMS is the first amplitude root mean square, AM is the first amplitude absolute average, CF is the first amplitude peak factor, N is the total number of sampling frequency points, Y(i) is the amplitude corresponding to the frequency point of the first amplitude-frequency characteristic curve when the frequency is i, and Y max (i) is the maximum amplitude value in the first amplitude-frequency characteristic curve.

[0043] In a specific embodiment, the first amplitude kurtosis and the second amplitude margin factor are obtained using the following formula:

[0044]

[0045] Wherein, Ku is the first amplitude kurtosis, MF is the second amplitude margin factor, N is the total number of sampling frequency points, Y(i) is the amplitude corresponding to the frequency point of the first amplitude-frequency characteristic curve when the frequency is i, and Y max (i) is the maximum amplitude value in the first amplitude-frequency characteristic curve, is the average amplitude value of the first amplitude-frequency characteristic curve.

[0046] In a specific embodiment, the axial displacement fault diagnosis result of the second transformer is obtained based on the first waveform characteristic reference value and the second waveform characteristic reference value, including: if the second amplitude root mean square is greater than the first amplitude root mean square, the second amplitude absolute average value is greater than the first amplitude absolute average value, the second amplitude peak factor is less than the first amplitude peak factor and the second amplitude margin factor is less than the first amplitude margin factor, then an axial displacement fault occurs in the winding of the second transformer.

[0047] Specifically, the axial displacement fault is judged by comparing the waveform characteristics of the first transformer with the waveform characteristic values ​​of the second transformer:

[0048] If the RMS of the second transformer is greater than the RMS of the first transformer, the AM of the second transformer is greater than the AM of the first transformer, and the CF of the second transformer is less than the CF of the first transformer, and the MF of the second transformer is less than the MF of the first transformer, it can be determined that an axial displacement fault has occurred in the transformer winding.

[0049] In a specific embodiment, the method further includes: the larger the value of the second amplitude root mean square or the second amplitude absolute average value is, the more serious the degree of the axial displacement fault of the second transformer winding is.

[0050] In a specific embodiment, the method further includes: the smaller the value of the second amplitude peak factor or the second amplitude margin factor is, the more serious the degree of the axial displacement fault of the second transformer winding is.

[0051] Specifically, as the degree of axial displacement fault increases, the RMS and AM feature values ​​show an increasing trend, while the CF and MF feature values ​​gradually decrease.

[0052] In a specific embodiment, the method further includes: when the second transformer winding has an axial displacement fault, if the second amplitude kurtosis is less than the first amplitude kurtosis, an axial displacement fault occurs in a preset upper region of the winding; if the second amplitude kurtosis is greater than the first amplitude kurtosis, an axial displacement fault occurs in a preset middle region and a preset lower region of the winding. Specifically, when the winding fails, if the Ku of the second transformer is less than the Ku of the first transformer, it can be determined that an axial displacement fault occurs in the upper region of the winding, and conversely, if the Ku of the second transformer is greater than the Ku of the first transformer, it can be determined that an axial displacement fault occurs in the middle and lower regions of the winding.

[0053] In the specific embodiments, see Figure 3, is a structural schematic diagram of a transformer winding axial displacement fault diagnosis system in the second embodiment of the present application, the system comprising: a response signal acquisition module 301, a first amplitude-frequency characteristic curve acquisition module 302, a second amplitude-frequency characteristic curve acquisition module 303, a first characteristic reference value acquisition module 304, a second characteristic reference value acquisition module 305 and a diagnosis module 306; the response signal acquisition module 301 is used to inject a first excitation signal of different frequencies into the first transformer and the second transformer, and obtain a first response signal output by the first transformer and a second response signal output by the second transformer; the first transformer is a transformer without a winding fault, and the second transformer is a transformer with a winding fault; the first amplitude-frequency characteristic curve acquisition module 302 is used to obtain a first amplitude-frequency characteristic curve of the first transformer according to the first excitation signal and the first response signal; the second amplitude-frequency characteristic curve acquisition module 303 is used to obtain the first amplitude-frequency characteristic curve of the first transformer according to the first excitation signal and the first response signal a second amplitude-frequency characteristic curve of the second transformer; the first characteristic reference value acquisition module 304 is used to obtain the first waveform characteristic reference value of the first transformer according to the total number of first sampling frequency points of the first amplitude-frequency characteristic curve and the first amplitude of the frequency points in the first amplitude-frequency characteristic curve; the first waveform characteristic reference value includes a first amplitude root mean square, a first amplitude absolute average value, a first amplitude kurtosis, a first amplitude peak factor and a first amplitude margin factor; the second characteristic reference value acquisition module 305 is used to obtain the second waveform characteristic reference value of the second transformer according to the total number of second sampling frequency points of the second amplitude-frequency characteristic curve and the second amplitude of the frequency points in the second amplitude-frequency characteristic curve; the second waveform characteristic reference value includes a second amplitude root mean square, a second amplitude absolute average value, a second amplitude kurtosis, a second amplitude peak factor and a second amplitude margin factor; the diagnosis module 306 is used to obtain the axial displacement fault diagnosis result of the winding of the second transformer according to the first waveform characteristic reference value and the second waveform characteristic reference value.

[0054] The system in this embodiment obtains a first waveform characteristic reference value by performing feature extraction on the first amplitude-frequency characteristic curve of the transformer without winding fault, and obtains a second waveform characteristic reference value by performing feature extraction on the second amplitude-frequency characteristic curve of the transformer with winding fault. The method of diagnosing winding fault by comparing the first waveform characteristic reference value with the second waveform characteristic reference value does not require human judgment and has the advantages of fast, efficient and accurate diagnosis of winding faults, thereby improving the accuracy of transformer winding fault diagnosis and can ensure the safe and stable operation of the transformer to a greater extent.

[0055] In a specific embodiment, the third embodiment of the present application provides a transformer winding axial displacement fault diagnosis device, including a memory and a processor, the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method described in any one of the first embodiments of the present application.

[0056] In a specific embodiment, the fourth embodiment of the present application provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the processor executes the steps of the method as described in any one of the first embodiments of the present application.

[0057] Figure 4 The internal structure of a computer device in one embodiment is shown. The computer device can be a terminal or a server. Figure 4 The computer device includes a processor, a memory, etc. connected via a system bus. The memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the computer device stores an operating system and may also store a computer program. When the computer program is executed by the processor, the processor can implement the method in this embodiment. The internal memory may also store a computer program. When the computer program is executed by the processor, the processor can implement the method in this embodiment. Those skilled in the art can understand that Figure 4 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0058] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

[0059] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A transformer winding axial displacement fault diagnosis method, characterized in that: The method comprises: Injecting first excitation signals of different frequencies into a first transformer and a second transformer, and obtaining a first response signal output by the first transformer and a second response signal output by the second transformer; the first transformer is a transformer without winding fault, and the second transformer is a transformer with winding fault; Obtaining a first amplitude-frequency characteristic curve of the first transformer according to the first excitation signal and the first response signal; Obtaining a second amplitude-frequency characteristic curve of the second transformer according to the first excitation signal and the second response signal; Obtaining a first waveform characteristic reference value of the first transformer according to the total number of first sampling frequency points of the first amplitude-frequency characteristic curve and the first amplitude of the frequency point in the first amplitude-frequency characteristic curve; the first waveform characteristic reference value includes a first amplitude root mean square value, a first amplitude absolute average value, a first amplitude kurtosis, a first amplitude peak factor and a first amplitude margin factor; Obtaining a second waveform characteristic reference value of the second transformer according to the total number of second sampling frequency points of the second amplitude-frequency characteristic curve and the second amplitude of the frequency point in the second amplitude-frequency characteristic curve; the second waveform characteristic reference value includes a second amplitude root mean square, a second amplitude absolute average, a second amplitude kurtosis, a second amplitude peak factor, and a second amplitude margin factor; An axial displacement fault diagnosis result of the second transformer winding is obtained according to the first waveform characteristic reference value and the second waveform characteristic reference value.

2. The transformer winding axial displacement fault diagnosis method according to claim 1, characterized in that: The obtaining of the axial displacement fault diagnosis result of the second transformer according to the first waveform characteristic reference value and the second waveform characteristic reference value includes: If the second amplitude root mean square is greater than the first amplitude root mean square, the second amplitude absolute average is greater than the first amplitude absolute average, the second amplitude peak factor is less than the first amplitude peak factor, and the second amplitude margin factor is less than the first amplitude margin factor, then an axial displacement fault occurs in the second transformer winding.

3. The transformer winding axial displacement fault diagnosis method according to claim 2, characterized in that: The method further comprises: The greater the value of the second amplitude root mean square or the second amplitude absolute average value is, the more serious the axial displacement fault of the second transformer winding is.

4. The transformer winding axial displacement fault diagnosis method according to claim 2, characterized in that: The method further comprises: The smaller the value of the second amplitude peak factor or the second amplitude margin factor is, the more serious the axial displacement fault of the second transformer winding is.

5. The transformer winding axial displacement fault diagnosis method according to claim 2, characterized in that: The method further comprises: When an axial displacement fault occurs in the second transformer winding, if the second amplitude kurtosis is less than the first amplitude kurtosis, an axial displacement fault occurs in a preset upper region of the winding; If the second amplitude kurtosis is greater than the first amplitude kurtosis, an axial displacement fault occurs in a preset middle region and a preset lower region of the winding.

6. The transformer winding axial displacement fault diagnosis method according to claim 1, characterized in that: The first amplitude root mean square, the first amplitude absolute average value and the first amplitude peak factor are obtained by using the following formula: Wherein, RMS is the first amplitude root mean square, AM is the first amplitude absolute average, CF is the first amplitude peak factor, N is the total number of sampling frequency points, Y(i) is the amplitude corresponding to the frequency point of the first amplitude-frequency characteristic curve when the frequency is i, and Y max (i) is the maximum amplitude value in the first amplitude-frequency characteristic curve.

7. The transformer winding axial displacement fault diagnosis method according to claim 1, characterized in that: The first amplitude kurtosis and the second amplitude margin factor are obtained by using the following formula: Wherein, Ku is the first amplitude kurtosis, MF is the second amplitude margin factor, N is the total number of sampling frequency points, Y(i) is the amplitude corresponding to the frequency point of the first amplitude-frequency characteristic curve when the frequency is i, and Y max (i) is the maximum amplitude value in the first amplitude-frequency characteristic curve, is the average amplitude value of the first amplitude-frequency characteristic curve.

8. A transformer winding axial displacement fault diagnosis system, characterized in that: The system comprises: a response signal acquisition module, a first amplitude-frequency characteristic curve acquisition module, a second amplitude-frequency characteristic curve acquisition module, a first characteristic reference value acquisition module, a second characteristic reference value acquisition module and a diagnosis module; The response signal acquisition module is used to inject first excitation signals of different frequencies into the first transformer and the second transformer, and acquire a first response signal output by the first transformer and a second response signal output by the second transformer; the first transformer is a transformer without winding fault, and the second transformer is a transformer with winding fault; The first amplitude-frequency characteristic curve acquisition module is used to obtain a first amplitude-frequency characteristic curve of the first transformer according to the first excitation signal and the first response signal; The second amplitude-frequency characteristic curve acquisition module is used to obtain a second amplitude-frequency characteristic curve of the second transformer according to the first excitation signal and the second response signal; The first characteristic reference value acquisition module is used to obtain a first waveform characteristic reference value of the first transformer according to the total number of first sampling frequency points of the first amplitude-frequency characteristic curve and the first amplitude of the frequency point in the first amplitude-frequency characteristic curve; the first waveform characteristic reference value includes a first amplitude root mean square value, a first amplitude absolute average value, a first amplitude kurtosis, a first amplitude peak factor and a first amplitude margin factor; The second characteristic reference value acquisition module is used to obtain a second waveform characteristic reference value of the second transformer according to the total number of second sampling frequency points of the second amplitude-frequency characteristic curve and the second amplitude of the frequency point in the second amplitude-frequency characteristic curve; the second waveform characteristic reference value includes a second amplitude root mean square, a second amplitude absolute average, a second amplitude kurtosis, a second amplitude peak factor and a second amplitude margin factor; The diagnosis module is used to obtain an axial displacement fault diagnosis result of the second transformer winding according to the first waveform characteristic reference value and the second waveform characteristic reference value.

9. A transformer winding axial displacement fault diagnosis device, comprising a memory and a processor, characterized in that: The memory stores a computer program, and when the computer program is executed by the processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 7.

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