Transformer winding fault area positioning method and related equipment

Abstract

The embodiment of the invention discloses a transformer winding fault area positioning method and related equipment, and the method comprises the steps: obtaining a current signal and a voltage signal of a low-voltage side and a current signal and a voltage signal of a middle-high-voltage side, obtaining a winding fault direction coefficient based on the current signals and the voltage signals, and positioning a winding fault area. Off-line detection and judgment on the transformer are not needed, normal production and operation of a power grid are not affected, the fault positioning method is simple and accurate, operators do not need to have high professional skills, and the labor cost is reduced.

Description

[Technical field]

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

[0002] As a key equipment in the power system, the safe and stable operation of the transformer is crucial to the normal operation of the entire power grid. Among the many faults of the transformer, winding faults are particularly common and are often difficult to detect and locate in time. Winding faults may not only cause damage to power equipment, but also affect the normal operation of the power grid, causing huge economic losses and social impacts.

[0003] Transformer winding faults often occur internally, and traditional detection methods are difficult to directly observe and diagnose, especially when the transformer is in operation. In addition, there are various types of transformer winding faults, including winding deformation, turn-to-turn short circuit, etc. Early diagnosis of these faults is crucial to prevent the expansion of faults. However, most existing diagnostic methods are offline and require power outages, which not only affects the normal operation of the power grid, but also requires high professional skills of operators, increasing labor costs. [Summary of the invention]

[0004] In view of this, the present invention provides a method for locating a transformer winding fault area and related equipment.

[0005] The specific technical scheme of the first embodiment of the present invention is: a method for locating a transformer winding fault area, the method comprising: injecting a high-frequency square wave periodic signal into the low-voltage side of the transformer, obtaining a first current signal and a first voltage signal of the low-voltage side response of the transformer, and obtaining a second current signal and a second voltage signal of the medium and high voltage measurement response of the transformer; obtaining a winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal and the second voltage signal; the winding fault direction coefficient is used to characterize the direction in which the transformer winding fails; obtaining a fault area locating result of the transformer winding according to the winding fault direction coefficient and a preset threshold; the fault area locating result includes an upper winding fault, a middle winding fault and a lower winding fault.

[0006] Preferably, obtaining the winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal and the second voltage signal includes: decomposing the first current signal to obtain the first phase and the first amplitude of the multiple harmonics corresponding to the first current signal; decomposing the first voltage signal to obtain the second phase and the second amplitude of the multiple harmonics corresponding to the first voltage signal; decomposing the second current signal to obtain the third phase and the third amplitude of the multiple harmonics corresponding to the second current signal; decomposing the second voltage signal to obtain the fourth phase and the fourth amplitude of the multiple harmonics corresponding to the second voltage signal; obtaining the winding fault direction coefficient of the transformer according to the first phase, the first amplitude, the second phase, the second amplitude, the third phase, the third amplitude, the fourth phase and the fourth amplitude.

[0007] Preferably, the method of obtaining the winding fault direction coefficient of the transformer according to the first phase, the first amplitude, the second phase, the second amplitude, the third phase, the third amplitude, the fourth phase and the fourth amplitude includes: obtaining a first phase difference weight between the first phase and the third phase; obtaining a second phase difference weight between the second phase and the fourth phase; obtaining a first amplitude weight between the first amplitude and the third amplitude; obtaining a second amplitude weight between the third amplitude and the fourth amplitude; obtaining a first winding fault direction factor according to the first phase difference weight and the second phase difference weight; obtaining a second winding fault direction factor according to the first amplitude weight and the second amplitude weight; obtaining the winding fault direction coefficient according to the first winding fault direction factor and the second winding fault direction factor.

[0008] Preferably, the first phase difference weight is obtained using the following formula:

[0009]

[0010] Among them, Ω x is the first phase difference weight, is the first phase of the nth harmonic corresponding to the first current signal, is the third phase of the nth harmonic corresponding to the second current signal.

[0011] Preferably, the first amplitude weight is obtained using the following formula:

[0012]

[0013] Among them, x is the first amplitude weight, A nis the first amplitude of the nth harmonic corresponding to the first current signal, C n is the third amplitude of the nth harmonic corresponding to the second current signal.

[0014] Preferably, the first winding fault direction factor is obtained using the following formula:

[0015]

[0016] Where λ1 is the fault direction factor of the first winding, Ω x is the first phase difference weight, Ω y is the second phase difference weight.

[0017] Preferably, the winding fault direction coefficient is obtained using the following formula:

[0018]

[0019] Wherein, η is the winding fault direction coefficient, λ1 is the first winding fault direction factor, and λ2 is the second winding fault direction factor.

[0020] The specific technical scheme of the second embodiment of the present invention is: a transformer winding fault area positioning system, the system comprising: a signal acquisition module, a fault direction coefficient acquisition module and a fault area positioning acquisition module; the signal acquisition module is used to inject a high-frequency square wave periodic signal into the low-voltage side of the transformer, obtain the first current signal and the first voltage signal of the low-voltage side response of the transformer, and obtain the second current signal and the second voltage signal of the medium and high voltage measurement response of the transformer; the fault direction coefficient acquisition module is used to obtain the winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal and the second voltage signal; the winding fault direction coefficient is used to characterize the direction in which the transformer winding fails; the fault area positioning acquisition module is used to obtain the fault area positioning result of the transformer winding according to the winding fault direction coefficient and a preset threshold; the fault area positioning result includes an upper winding fault, a middle winding fault and a lower winding fault.

[0021] The specific technical solution of the third embodiment of the present invention is: a transformer winding fault area locating 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.

[0022] 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.

[0023] Implementing the embodiments of the present invention will have the following beneficial effects:

[0024] The present invention injects a high-frequency square wave periodic signal into the low-voltage side of the transformer to obtain a first current signal and a first voltage signal of the transformer's low-voltage side response, and obtains a second current signal and a second voltage signal of the transformer's medium- and high-voltage measurement response; obtains the transformer's winding fault direction coefficient according to the first current signal, the first voltage signal, the second current signal, and the second voltage signal; obtains the transformer's winding fault area positioning result according to the winding fault direction coefficient and a preset threshold. By obtaining the current signal and voltage signal of the low-voltage side and the current signal and voltage signal of the medium- and high-voltage side, and obtaining the winding fault direction coefficient based on the above-mentioned current signal and voltage signal, the winding fault area is located, without the need to perform offline detection and judgment on the transformer, without affecting the normal production and operation of the power grid, and the fault location method is simple and accurate, without requiring the operator to have high professional skills, reducing labor costs.

Brief Description of the Drawings

[0025] 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.

[0026] Figure 1 A flowchart of a method for locating a transformer winding fault area;

[0027] Figure 2 It is a structural diagram of the online positioning experimental platform;

[0028] Figure 3 It is a structural schematic diagram of a transformer winding fault area positioning system;

[0029] Figure 4 It is a diagram of the internal structure of a computer device;

[0030] Among them, 201, AC source; 202, rectifier module; 203, filter module; 204, inverter module; 205, power protection resistor; 206, coupling transformer; 207, station transformer; 208, low-voltage side current signal meter; 209, low-voltage side voltage signal meter; 210, main transformer experimental object; 211, medium and high voltage side current signal meter; 212, capacitive voltage transformer; 213, medium and high voltage side voltage signal meter; 214, transformer peripheral equivalent circuit; 215, simulation online operation module; 216, PWM drive module; 217, lower computer FPGA; 218, upper computer; 219, experimental platform; 301, signal acquisition module; 302, fault direction coefficient acquisition module; 303, fault area positioning acquisition module. [Specific implementation method]

[0031] 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.

[0032] 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.

[0033] 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.

[0034] See also Figure 1 , is a flowchart of a method for locating a transformer winding fault area in the first embodiment of the present application, thereby locating the area of ​​the winding fault, the method comprising:

[0035] Step 101, injecting a high-frequency square wave periodic signal into the low-voltage side of the transformer, obtaining a first current signal and a first voltage signal of the low-voltage side response of the transformer, and obtaining a second current signal and a second voltage signal of the medium- and high-voltage side response of the transformer;

[0036] Step 102: obtaining a winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal, and the second voltage signal; the winding fault direction coefficient is used to characterize the direction in which the winding fault of the transformer occurs;

[0037] Step 103, obtaining a fault area positioning result of the transformer winding according to the winding fault direction coefficient and a preset threshold; the fault area positioning result includes an upper winding fault, a middle winding fault and a lower winding fault.

[0038] For details, please refer to Figure 2, use the online positioning experimental platform to obtain the fault area positioning result of the transformer winding. The online positioning experimental platform includes: AC source 201, rectifier module 202, filter module 203, inverter module 204, power protection resistor 205, coupling transformer 206, station transformer 207, low voltage side current signal meter 208, low voltage side voltage signal meter 209, main transformer experimental object 210, medium and high voltage side current signal meter 211, capacitive voltage transformer 212, medium and high voltage side voltage signal meter 213, transformer peripheral equivalent circuit 214, simulation online operation module 215, PWM drive module 216, lower computer FPGA 217, host computer 218 and experimental platform 219, wherein the host computer 218 is responsible for the online positioning and evaluation process of the entire transformer winding fault area. First, the AC source 201 obtains a DC voltage signal through the rectifier module 202 and the filter module 203, and the DC voltage signal is converted into a square wave periodic signal through the inverter module 204. The drive signals of the four switch tubes on the inverter bridge are controlled by the host computer 218 to control the PWM drive module 216 and the lower computer FPGA 217 is generated; the power protection resistor 205 is used to protect the power supply device, and the coupling transformer 206 is used to couple the high-frequency square wave signal to the low-voltage side of the transformer. The high-frequency square wave signal is coupled by the coupling transformer 206 and then injected into the low-voltage side of the transformer by means of the station transformer 207. The main transformer experimental object 210 is the experimental object of the online positioning experimental platform of the entire transformer winding fault area; the low-voltage side current signal meter 208 and the low-voltage side voltage signal meter 209 can detect the voltage and current signals at the injection point of the low-voltage side, and the capacitive voltage transformer 212 is a device that is convenient for the medium-voltage side and the high-voltage side to detect the output signal. The medium and high-voltage side current signal The instrument 211 and the medium and high voltage side voltage signal instrument 213 can detect the voltage and current signals at the medium and high voltage side response points; the transformer peripheral equivalent circuit 214 simulates the equivalent circuit parameters of the transformer under normal power frequency operation, and the simulated online operation module 215 is a power frequency operation power supply device corresponding to the transformer grade and model; first, the electrical signal data of each position is obtained according to the electrical signal detector of the online positioning experimental platform of the transformer winding fault area, and then the obtained data is analyzed and processed to obtain the winding fault direction factor of the transformer online operation, and finally the winding fault direction coefficient of the transformer online operation is obtained to determine the winding fault area of ​​the transformer online operation.

[0039] The method in this embodiment obtains the current signal and voltage signal on the low voltage side and the current signal and voltage signal on the medium and high voltage side, and obtains the winding fault direction coefficient based on the above current signal and voltage signal, thereby locating the area of ​​the winding fault. There is no need to perform offline detection and judgment on the transformer, and the normal production and operation of the power grid is not affected. The fault locating method is simple and accurate, and does not require the operator to have high professional skills, thereby reducing labor costs.

[0040] In a specific embodiment, obtaining the winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal and the second voltage signal includes: decomposing the first current signal to obtain the first phase and the first amplitude of the multiple harmonics corresponding to the first current signal; decomposing the first voltage signal to obtain the second phase and the second amplitude of the multiple harmonics corresponding to the first voltage signal; decomposing the second current signal to obtain the third phase and the third amplitude of the multiple harmonics corresponding to the second current signal; decomposing the second voltage signal to obtain the fourth phase and the fourth amplitude of the multiple harmonics corresponding to the second voltage signal; obtaining the winding fault direction coefficient of the transformer according to the first phase, the first amplitude, the second phase, the second amplitude, the third phase, the third amplitude, the fourth phase and the fourth amplitude.

[0041] Specifically, the upper computer 218 controls the PWM drive module 216 and the lower computer FPGA 217 to generate a drive signal. The AC source 201 obtains a DC voltage signal through the rectifier module 202 and the filter module 203. The DC voltage signal is fully inverted by the inverter module 204 to obtain a high-frequency square wave periodic signal. The high-frequency square wave signal is coupled by the coupling transformer 206 and then injected into the low-voltage side of the transformer by means of the station transformer 207. The low-voltage side current signal meter 208 and the low-voltage side voltage signal meter 209 detect the first voltage signal U at the injection point on the low-voltage side. L , current signal I L , the specific formula is:

[0042]

[0043] Among them, A0 is U L After decomposition, it corresponds to the amplitude of the 0th harmonic, A1 is U L The amplitude of the first harmonic after decomposition, ω A1 For U L The angular frequency corresponding to the first harmonic after decomposition is, For U L The phase of the first harmonic after decomposition, A n For U L After decomposition, it corresponds to the amplitude of the nth harmonic. Similarly, B n For I L The decomposed value, t represents time;

[0044] The medium and high voltage side current signal instrument 211 and the medium and high voltage side voltage signal instrument 213 detect the second voltage signal U at the medium and high voltage side response. H , the second current signal I H , the specific formula is:

[0045]

[0046] Where C0 is U H After decomposition, it corresponds to the amplitude of the 0th harmonic, and C1 is U H The amplitude of the first harmonic after decomposition, ω C1 For U H The angular frequency corresponding to the first harmonic after decomposition is, For U H The phase of the first harmonic after decomposition, C n For U H After decomposition, it corresponds to the amplitude of the nth harmonic. Similarly, D n For I H The decomposed value, t represents time.

[0047] In a specific embodiment, the method of obtaining the winding fault direction coefficient of the transformer according to the first phase, the first amplitude, the second phase, the second amplitude, the third phase, the third amplitude, the fourth phase and the fourth amplitude includes: obtaining the first phase difference weight between the first phase and the third phase; obtaining the second phase difference weight between the second phase and the fourth phase; obtaining the first amplitude weight between the first amplitude and the third amplitude; obtaining the second amplitude weight between the third amplitude and the fourth amplitude; obtaining the first winding fault direction factor according to the first phase difference weight and the second phase difference weight; obtaining the second winding fault direction factor according to the first amplitude weight and the second amplitude weight; obtaining the winding fault direction coefficient according to the first winding fault direction factor and the second winding fault direction factor. By measuring the voltage and current signals output by the winding, including the amplitude and phase, key information of the winding operation status can be obtained. After processing, the information can generate a fault direction factor to help quickly locate the fault area. This method is more accurate than the traditional method based on fault phenomenon or empirical judgment because it is directly analyzed based on the physical state inside the winding.

[0048] In a specific embodiment, the first phase difference weight is obtained by using the following formula:

[0049]

[0050] Among them, Ω x is the first phase difference weight, is the first phase of the nth harmonic corresponding to the first current signal, is the third phase of the nth harmonic corresponding to the second current signal.

[0051] In a specific embodiment, the second phase difference weight is obtained by using the following formula:

[0052]

[0053] Among them, Ω y is the second phase difference weight, is the second phase of the nth harmonic corresponding to the second current signal, is the fourth phase of the nth harmonic corresponding to the fourth current signal.

[0054] In a specific embodiment, the first amplitude weight is obtained by using the following formula:

[0055]

[0056] Among them, x is the first amplitude weight, A n is the first amplitude of the nth harmonic corresponding to the first current signal, C n is the third amplitude of the nth harmonic corresponding to the second current signal.

[0057] In a specific embodiment, the second amplitude weight is obtained by using the following formula:

[0058]

[0059] Among them, y is the second amplitude weight, B n is the second amplitude of the nth harmonic corresponding to the second current signal, D n is the fourth amplitude of the nth harmonic corresponding to the fourth current signal.

[0060] In a specific embodiment, the first winding fault direction factor is obtained by using the following formula:

[0061]

[0062] Where λ1 is the fault direction factor of the first winding, Ω x is the first phase difference weight, Ω y is the second phase difference weight.

[0063] In a specific embodiment, the first winding fault direction factor is obtained by using the following formula:

[0064]

[0065] Wherein, λ2 is the fault direction factor of the second winding, T x is the first amplitude weight, T y is the second amplitude weight.

[0066] In a specific embodiment, the winding fault direction coefficient is obtained using the following formula:

[0067]

[0068] Wherein, η is the winding fault direction coefficient, λ1 is the first winding fault direction factor, and λ2 is the second winding fault direction factor.

[0069] In a specific embodiment, the winding fault direction coefficient η of the transformer in online operation can determine the winding fault area of ​​the transformer in online operation. If η>0.85, it indicates that the upper winding of the transformer is faulty; if 0.56≤η≤0.85, it indicates that the middle winding of the transformer is faulty; if η<0.56, it indicates that the lower winding of the transformer is faulty.

[0070] This method injects a high-frequency square wave signal at the low-voltage side winding of the transformer and obtains a high-frequency electrical signal on the response side; analyzes and processes the electrical signal data detected on the low-voltage side and the induction side to obtain some parameters, then fits and calculates the processed parameters to obtain the winding fault direction factor of the transformer in online operation, and finally fits the winding fault direction factor to obtain the winding fault direction coefficient to determine the winding fault area of ​​the transformer in online operation. This method does not require offline detection and judgment, does not affect the normal production and operation of the power grid, and therefore provides an accurate judgment method for online positioning of the fault area of ​​the transformer winding.

[0071] In the specific embodiments, see Figure 3 , is a structural schematic diagram of a transformer winding fault area positioning system in the third embodiment of the present application, the system comprising: a signal acquisition module 301, a fault direction coefficient acquisition module 302 and a fault area positioning acquisition module 303; the signal acquisition module 301 is used to inject a high-frequency square wave periodic signal into the low-voltage side of the transformer, obtain a first current signal and a first voltage signal of the low-voltage side response of the transformer, and obtain a second current signal and a second voltage signal of the medium and high voltage measurement response of the transformer; the fault direction coefficient acquisition module 302 is used to obtain the winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal and the second voltage signal; the winding fault direction coefficient is used to characterize the direction in which the transformer winding fails; the fault area positioning acquisition module 303 is used to obtain the fault area positioning result of the transformer winding according to the winding fault direction coefficient and a preset threshold; the fault area positioning result includes an upper winding fault, a middle winding fault and a lower winding fault.

[0072] The system in this embodiment obtains the current signal and voltage signal on the low voltage side and the current signal and voltage signal on the medium and high voltage sides, and obtains the winding fault direction coefficient based on the above current signal and voltage signal, thereby locating the area of ​​the winding fault. There is no need to perform offline detection and judgment on the transformer, and the normal production and operation of the power grid is not affected. The fault locating method is simple and accurate, and there is no need to require the operator to have high professional skills, thereby reducing labor costs.

[0073] In a specific embodiment, the third embodiment of the present application is a transformer winding fault area positioning 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. The device in this embodiment obtains the current signal and voltage signal on the low voltage side and the current signal and voltage signal on the medium and high voltage side, and obtains the winding fault direction coefficient based on the above current signal and voltage signal, thereby locating the area of ​​the winding fault, without the need to perform offline detection and judgment on the transformer, and does not affect the normal production and operation of the power grid, and the fault location method is simple and accurate, does not require the operator to have high professional skills, and reduces labor costs.

[0074] In a specific embodiment, the fourth embodiment of the present application is a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the processor executes the steps of the method described in any one of the first embodiments of the present application. The storage medium in this embodiment obtains the current signal and voltage signal on the low voltage side and the current signal and voltage signal on the medium and high voltage side, and obtains the winding fault direction coefficient based on the above current signal and voltage signal, thereby locating the area of ​​the winding fault, without the need to perform offline detection and judgment on the transformer, and does not affect the normal production and operation of the power grid. The fault location method is simple and accurate, and does not require the operator to have high professional skills, thereby reducing labor costs. 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 4The 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.

[0075] 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.

[0076] 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 method for locating a transformer winding fault area, characterized in that: The method comprises: Injecting a high-frequency square wave periodic signal into the low-voltage side of the transformer, obtaining a first current signal and a first voltage signal of the low-voltage side response of the transformer, and obtaining a second current signal and a second voltage signal of the medium- and high-voltage side response of the transformer; Obtaining a winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal and the second voltage signal; the winding fault direction coefficient is used to characterize the direction in which the winding of the transformer fails; The fault area positioning result of the transformer winding is obtained according to the winding fault direction coefficient and the preset threshold; the fault area positioning result includes the fault of the upper winding, the fault of the middle winding and the fault of the lower winding.

2. The method for locating a transformer winding fault area according to claim 1, characterized in that: The obtaining of the winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal and the second voltage signal comprises: Decomposing the first current signal to obtain a first phase and a first amplitude of multiple harmonics corresponding to the first current signal; Decomposing the first voltage signal to obtain a second phase and a second amplitude of multiple harmonics corresponding to the first voltage signal; Decomposing the second current signal to obtain a third phase and a third amplitude of multiple harmonics corresponding to the second current signal; Decomposing the second voltage signal to obtain a fourth phase and a fourth amplitude of multiple harmonics corresponding to the second voltage signal; A winding fault direction coefficient of the transformer is obtained according to the first phase, the first amplitude, the second phase, the second amplitude, the third phase, the third amplitude, the fourth phase and the fourth amplitude.

3. The method for locating a transformer winding fault area according to claim 2, characterized in that: The obtaining of the winding fault direction coefficient of the transformer according to the first phase, the first amplitude, the second phase, the second amplitude, the third phase, the third amplitude, the fourth phase and the fourth amplitude comprises: Acquire a first phase difference weight between the first phase and the third phase; Acquire a second phase difference weight between the second phase and the fourth phase; Obtaining a first amplitude weight between the first amplitude and the third amplitude; Obtaining a second amplitude weight between the third amplitude and the fourth amplitude; Obtaining a first winding fault direction factor according to the first phase difference weight and the second phase difference weight; Obtaining a second winding fault direction factor according to the first amplitude weight and the second amplitude weight; The winding fault direction coefficient is obtained according to the first winding fault direction factor and the second winding fault direction factor.

4. The method for locating a transformer winding fault area according to claim 3, characterized in that: The first phase difference weight is obtained by using the following formula: Among them, Ω x is the first phase difference weight, is the first phase of the nth harmonic corresponding to the first current signal, is the third phase of the nth harmonic corresponding to the second current signal.

5. The method for locating a transformer winding fault area according to claim 3, characterized in that: The first amplitude weight is obtained by using the following formula: Among them, x is the first amplitude weight, A n is the first amplitude of the nth harmonic corresponding to the first current signal, C n is the third amplitude of the nth harmonic corresponding to the second current signal.

6. The method for locating a transformer winding fault area according to claim 3, characterized in that: The first winding fault direction factor is obtained by the following formula: Where λ1 is the fault direction factor of the first winding, Ω x is the first phase difference weight, Ω y is the second phase difference weight.

7. The method for locating a transformer winding fault area according to claim 3, characterized in that: The winding fault direction coefficient is obtained by the following formula: Wherein, η is the winding fault direction coefficient, λ1 is the first winding fault direction factor, and λ2 is the second winding fault direction factor.

8. A transformer winding fault area positioning system, characterized in that: The system comprises: a signal acquisition module, a fault direction coefficient acquisition module and a fault area location acquisition module; The signal acquisition module is used to inject a high-frequency square wave periodic signal into the low-voltage side of the transformer, obtain a first current signal and a first voltage signal of the low-voltage side response of the transformer, and obtain a second current signal and a second voltage signal of the medium- and high-voltage side response of the transformer; The fault direction coefficient acquisition module is used to obtain the winding fault direction coefficient of the transformer according to the first current signal, the first voltage signal, the second current signal and the second voltage signal; the winding fault direction coefficient is used to characterize the direction in which the winding of the transformer fails; The fault area positioning acquisition module is used to obtain the fault area positioning result of the transformer winding according to the winding fault direction coefficient and a preset threshold; the fault area positioning result includes a fault in the upper winding, a fault in the middle winding and a fault in the lower winding.

9. A transformer winding fault area positioning 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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