Transformer winding state on-line diagnosis method and related equipment

Abstract

The embodiment of the invention discloses a transformer winding state on-line diagnosis method and related equipment, and the method comprises the steps: injecting high-frequency voltage signals of different frequencies into a transformer, and obtaining a response voltage signal outputted by the transformer, thereby obtaining a relation curve of response voltage and frequency; obtaining a resonant frequency point in the relation curve; obtaining a resonance voltage value according to the resonance frequency point and a preset linear error factor; obtaining a winding state evaluation factor according to the resonance voltage value and the equivalent inductance value of the transformer; and obtaining a winding state diagnosis result of the transformer according to the winding state evaluation factor and a preset threshold value. According to the obtained resonance voltage value, the winding state evaluation factor is obtained to realize on-line detection of the winding state, and the transformer does not need to be shut down, so that normal operation and power supply reliability of the transformer are ensured, and the maintenance cost and the operation risk are reduced.

Description

[Technical field]

[0001] The present invention relates to the technical field of transformer winding fault analysis, and in particular to an online transformer winding state diagnosis method and related equipment. [Background technology]

[0002] As the core equipment in the power system, the stable operation of the transformer is crucial to ensuring the safety of the power grid and the reliability of power supply. Failure of the transformer winding may cause local discharge, local overheating and other problems. If not handled in time, it may cause more serious accidents, such as through-breakdown and insulation damage. Transformer winding deformation is one of the main causes of internal transformer failures. The current existing winding fault detection method is offline detection, which requires the transformer to be shut down for maintenance, which is not only time-consuming and labor-intensive, but also seriously affects the normal operation of the transformer and the reliability of power supply, and increases maintenance costs and operation risks. [Summary of the invention]

[0003] In view of this, the present invention provides a transformer winding status online diagnosis method and related equipment.

[0004] The specific technical scheme of the first embodiment of the present invention is: a method for online diagnosis of transformer winding status, the method comprising: injecting high-frequency voltage signals of different frequencies into the transformer, and obtaining a response voltage signal output by the transformer; drawing a relationship curve between the response voltage and frequency of the transformer according to the frequency and the response voltage signal; obtaining the resonant frequency point of the transformer in the relationship curve; obtaining the resonant voltage value of the transformer according to the resonant frequency point and a preset linear error factor; obtaining a winding status evaluation factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer; the winding status evaluation factor is used to characterize the winding status of the transformer; obtaining the winding status diagnosis result of the transformer according to the winding status evaluation factor and a preset threshold; the winding status diagnosis result includes winding faults and winding non-faults.

[0005] Preferably, the resonant voltage value is obtained using the following formula:

[0006]

[0007] Among them, U xz is the resonant voltage value, f i is the i-th resonant frequency point, f j is the jth resonant frequency point, y is the preset linear error factor, η is the integral variable, k1, k2, k3, k4, k5, k6, k7, k8, k9 and k 10 is a constant.

[0008] Preferably, the method also includes: taking minimizing the preset linear error factor as the goal, optimizing the preset linear error factor using the resonant voltage value and the actual resonant voltage value of the transformer to obtain an optimized linear error factor; then obtaining the resonant voltage value of the transformer according to the resonant frequency point and the preset linear error factor, including: obtaining the optimized resonant voltage value of the transformer according to the resonant frequency point and the optimized linear error factor; then obtaining the winding state evaluation factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer, including: obtaining the winding state evaluation factor of the transformer according to the optimized resonant voltage value and the equivalent inductance value of the transformer.

[0009] Preferably, the preset linear error factor is optimized by using the resonant voltage value and the actual resonant voltage value of the transformer with the goal of minimizing the preset linear error factor to obtain the optimized linear error factor, including: constructing an objective function of the preset linear error factor according to the resonant voltage value and the actual resonant voltage value of the transformer; with the goal of minimizing the preset linear error factor, iteratively optimizing the preset linear error factor by using the objective function to obtain the optimized linear error factor.

[0010] Preferably, the objective function is obtained using the following formula:

[0011]

[0012] Where, f(y) is the objective function, U xz_j is the resonant voltage value corresponding to the jth resonant frequency point, U s_j is the actual resonant voltage value corresponding to the jth resonant frequency point, and N is the number of resonant frequency points.

[0013] Preferably, the winding state evaluation factor is obtained using the following formula:

[0014]

[0015] Wherein, μ is the winding condition assessment factor, U' xz is the optimized resonant voltage value, c HG is the equivalent capacitance value of the capacitive voltage transformer connected to the transformer, l YQ is the equivalent inductance of the transformer, k 11 , k 12 , k 13 , k 14 , k 15 , k 16 , k 17 , k 18 , k19 and k 20 is a constant.

[0016] Preferably, the winding state diagnosis result of the transformer is obtained according to the winding state evaluation factor and the preset threshold, including: when the winding state evaluation factor is less than or equal to the preset threshold, the winding state diagnosis result is that the winding is not faulty; when the winding state evaluation factor is greater than the preset threshold, the winding state diagnosis result is that the winding is faulty.

[0017] The specific technical scheme of the second embodiment of the present invention is: a transformer winding state online diagnosis system, the system includes: a response voltage acquisition module, a relationship curve acquisition module, a resonant frequency point acquisition module, a resonant voltage value acquisition module, a state evaluation factor acquisition module and a diagnosis result acquisition module; the response voltage acquisition module is used to inject high-frequency voltage signals of different frequencies into the transformer and acquire the response voltage signal output by the transformer; the relationship curve acquisition module is used to draw a relationship curve between the response voltage and the frequency of the transformer according to the frequency and the response voltage signal; the resonant frequency point acquisition module is used to acquire the resonant frequency point of the transformer in the relationship curve; the resonant voltage value acquisition module is used to acquire the resonant voltage value of the transformer according to the resonant frequency point and a preset linear error factor; the state evaluation factor acquisition module is used to obtain the winding state evaluation factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer; the winding state evaluation factor is used to characterize the winding state of the transformer; the diagnosis result acquisition module is used to obtain the winding state diagnosis result of the transformer according to the winding state evaluation factor and a preset threshold; the winding state diagnosis result includes winding fault and winding no fault.

[0018] The specific technical solution of the third embodiment of the present invention is: a transformer winding status online diagnostic 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.

[0019] 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.

[0020] Implementing the embodiments of the present invention will have the following beneficial effects:

[0021] The present invention injects high-frequency voltage signals of different frequencies into the transformer, and obtains the response voltage signal output by the transformer to obtain the relationship curve between the response voltage and the frequency; obtains the resonant frequency point in the relationship curve; obtains the resonant voltage value according to the resonant frequency point and the preset linear error factor; obtains the winding state evaluation factor according to the resonant voltage value and the equivalent inductance value of the transformer; obtains the winding state diagnosis result of the transformer according to the winding state evaluation factor and the preset threshold value. The winding state evaluation factor is obtained according to the obtained resonant voltage value to realize the online detection of the winding state, without shutting down the transformer, thereby ensuring the normal operation and power supply reliability of the transformer, and reducing the maintenance cost and operation risk.

Brief Description of the Drawings

[0022] 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.

[0023] Figure 1 A flowchart of the steps of an online diagnosis method for transformer winding status;

[0024] Figure 2 It is a structural diagram of the online diagnostic test platform;

[0025] Figure 3 It is a structural schematic diagram of an online diagnosis system for transformer winding status;

[0026] Figure 4 It is a diagram of the internal structure of a computer device;

[0027] Among them, 201, host computer; 202, digital signal generator; 203, capacitive voltage transformer; 204, high-voltage bushing; 205, output bushing; 206, data acquisition device; 207, transformer box; 208, iron core; 209, low-voltage winding; 210, high-voltage winding; 211, AC power supply; 212, first grounding device; 213, second grounding device; 214, third grounding device; 215, first resistor; 216, second resistor; 217, first inductor; 218, second inductor; 301, response voltage acquisition module; 302, relationship curve acquisition module; 303, resonant frequency point acquisition module; 304, resonant voltage value acquisition module; 305, state evaluation factor acquisition module; 306, diagnosis result acquisition module. [Specific implementation method]

[0028] 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.

[0029] 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.

[0030] 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.

[0031] See also Figure 1 , is a flowchart of a method for online diagnosis of transformer winding status in the first embodiment of the present application, so as to ensure the normal operation and power supply reliability of the transformer, the method comprising:

[0032] Step 101, injecting high-frequency voltage signals of different frequencies into a transformer, and obtaining a response voltage signal output by the transformer;

[0033] Step 102: Draw a curve of the relationship between the response voltage and the frequency of the transformer according to the frequency and the response voltage signal;

[0034] Step 103, obtaining the resonant frequency point of the transformer in the relationship curve;

[0035] Step 104: obtaining a resonant voltage value of the transformer according to the resonant frequency point and a preset linear error factor;

[0036] Step 105: obtaining a winding state evaluation factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer; the winding state evaluation factor is used to characterize the winding state of the transformer;

[0037] Step 106: Obtain a winding state diagnosis result of the transformer according to the winding state evaluation factor and a preset threshold; the winding state diagnosis result includes a winding fault and a winding no fault.

[0038] For details, please refer to Figure 2 The online diagnostic test platform uses the response voltage signal of the transformer output. The online diagnostic test platform includes: a host computer 201, a digital signal generator 202, a capacitive voltage transformer 203, a high-voltage bushing 204, an output bushing 205, a data acquisition device 206, a transformer box 207, an iron core 208, a low-voltage winding 209, a high-voltage winding 210, an AC power supply 211, a first grounding device 212, a second grounding device 213, a third grounding device 214, a first resistor 215, a second resistor 216, a first inductor 217 and a second inductor 218; the host computer is connected to the digital signal generator, and the digital signal generator is connected to the digital signal generator. The signal generator is connected to the capacitive voltage transformer, the capacitive voltage transformer is connected to the high-voltage bushing, the high-voltage bushing is connected to the first resistor, the first inductor, the AC power supply and the first grounding device; the output bushing is connected to the data acquisition device, the data acquisition device is connected to the host computer, the output bushing is connected to the second resistor, the second inductor and the second grounding device; the iron core, the low-voltage winding and the high-voltage winding are all placed in the transformer box, and the transformer box is connected to the third grounding device; the first resistor, the first inductor, the AC power supply, the second resistor and the second inductor are used to simulate the online operation of the transformer.

[0039] The host computer sends a test high-frequency voltage setting signal to the digital signal generator. The digital signal generator injects the test high-frequency voltage signal into the high-voltage bushing through a capacitive voltage transformer, collects the response voltage signal of the output bushing through a data acquisition device, and transmits the data to the host computer. The host computer adjusts the frequency of the digital signal generator, takes frequency f1 as the starting value, and increases the frequency uniformly at a rate of ΔfHz / s. Every time it increases to a frequency point f i , the data acquisition device records the output voltage U i , and upload it to the host computer for storage; the host computer draws and analyzes the relationship curve between the output voltage and frequency. The relationship curve between voltage and frequency shows a "peak" shape near the resonant frequency, indicating that the circuit has the strongest response at this frequency, thereby obtaining all the resonant frequency points F xz =(f1 f2…f n ), and obtain the resonant voltage value U corresponding to the resonant frequency point xz =(u1 u2…u n ). A winding state evaluation factor of the transformer is obtained according to the resonant voltage value and the equivalent inductance value of the transformer; and a winding state diagnosis result of the transformer is obtained according to the winding state evaluation factor and a preset threshold value.

[0040] The method in this embodiment injects high-frequency voltage signals of different frequencies into the transformer, and obtains the response voltage signal output by the transformer to obtain the relationship curve between the response voltage and the frequency; obtains the resonant frequency point in the relationship curve; obtains the resonant voltage value according to the resonant frequency point and the preset linear error factor; obtains the winding state evaluation factor according to the resonant voltage value and the equivalent inductance value of the transformer; obtains the winding state diagnosis result of the transformer according to the winding state evaluation factor and the preset threshold value. Obtaining the winding state evaluation factor according to the obtained resonant voltage value realizes online detection of the winding state without shutting down the transformer, thereby ensuring the normal operation and power supply reliability of the transformer and reducing maintenance costs and operation risks.

[0041] In a specific embodiment, the resonant voltage value is obtained using the following formula:

[0042]

[0043] Among them, U xz is the resonant voltage value, f i is the i-th resonant frequency point, f j is the jth resonant frequency point, y is the preset linear error factor, η is the integral variable, k1, k2, k3, k4, k5, k6, k7, k8, k9 and k 10 is a constant.

[0044] Specifically, k1, k2, k3, k4, k5, k6, k7, k8, k9 and k 10 After setting to a specific constant, the resonant voltage value is obtained using the following formula:

[0045]

[0046] Among them, k1, k2, k3, k4, k5, k6, k7, k8, k9 and k 10 The specific value of can be set according to actual conditions, and this application does not further limit the value of the above constant.

[0047] In a specific embodiment, the method further includes: taking the minimization of the preset linear error factor as the goal, optimizing the preset linear error factor using the resonant voltage value and the actual resonant voltage value of the transformer to obtain an optimized linear error factor; then obtaining the resonant voltage value of the transformer according to the resonant frequency point and the preset linear error factor, including: obtaining the optimized resonant voltage value of the transformer according to the resonant frequency point and the optimized linear error factor; then obtaining the winding state evaluation factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer, including: obtaining the winding state evaluation factor of the transformer according to the optimized resonant voltage value and the equivalent inductance value of the transformer. Specifically, the linear error factor is optimized and modeled using an optimization algorithm to obtain a linear error factor that minimizes the error between the calculated value and the measured value of the resonant voltage, thereby obtaining the optimized resonant voltage value.

[0048] In a specific embodiment, the preset linear error factor is optimized by using the resonant voltage value and the actual resonant voltage value of the transformer with the goal of minimizing the preset linear error factor to obtain the optimized linear error factor, including: constructing an objective function of the preset linear error factor according to the resonant voltage value and the actual resonant voltage value of the transformer; with the goal of minimizing the preset linear error factor, iteratively optimizing the preset linear error factor by using the objective function to obtain the optimized linear error factor.

[0049] In a specific embodiment, the objective function is obtained using the following formula:

[0050]

[0051] Where, f(y) is the objective function, U xz_j is the resonant voltage value corresponding to the jth resonant frequency point, U s_j is the actual resonant voltage value corresponding to the jth resonant frequency point, and N is the number of resonant frequency points.

[0052] Specifically, the specific steps for optimizing the preset linear error factor are:

[0053] 1. Randomly generate the initial solution y and calculate the objective function f(y):

[0054]

[0055] Among them, f(y) is the objective function, U xz_j is the calculated value of the jth transformer winding resonant voltage, U s_j is the measured value of the jth transformer winding resonant voltage, and N is the number of resonant frequency points;

[0056] 2. Generate a new perturbed solution y' and calculate the objective function Δf = f(y) - f(y'); if Δf ≥ 0, accept the new solution; otherwise, obtain the new solution according to the probability acceptance criterion;

[0057] 3. Determine whether the number of iterations has been reached. If so, go to step 4; otherwise, go to step 2.

[0058] 4. Determine whether the termination condition is met. If so, the operation ends and the optimal solution is output. Otherwise, reset the number of iterations and go to step 2.

[0059] In a specific embodiment, the winding state evaluation factor is obtained using the following formula:

[0060]

[0061] Wherein, μ is the winding condition assessment factor, U' xz is the optimized resonant voltage value, c HG is the equivalent capacitance value of the capacitive voltage transformer connected to the transformer, l YQ is the equivalent inductance of the transformer, k 11 , k 12 , k 13 , k 14 , k 15 , k 16 , k 17 , k 18 , k 19 and k 20 is a constant.

[0062] In a specific embodiment, the calculation formula of the winding state evaluation factor is:

[0063]

[0064] Among them, k 11 , k 12 , k 13 , k 14 , k 15 , k 16 , k 17 , k 18 , k 19 and k 20 The specific value of can be set according to actual conditions, and this application does not further limit the value of the above constant.

[0065] In a specific embodiment, the winding state diagnosis result of the transformer is obtained according to the winding state evaluation factor and the preset threshold, including: when the winding state evaluation factor is less than or equal to the preset threshold, the winding state diagnosis result is that the winding is not faulty; when the winding state evaluation factor is greater than the preset threshold, the winding state diagnosis result is that the winding is faulty.

[0066] Specifically, when μ∈(0,K gz ], it indicates that the transformer winding has no fault; when μ∈(K gz ,∞), indicating that the transformer winding is faulty, where K gz It is a constant related to the transformer and capacitor voltage transformer model.

[0067] The method in this embodiment can determine whether a fault occurs in the winding of an online transformer. The method has a strong anti-interference ability and can promptly detect potential problems in the transformer winding, thereby taking preventive measures to avoid further development of the fault. This is of great significance for promoting the development and application of transformer status diagnosis technology in smart grids.

[0068] In the specific embodiments, see Figure 3 , is a structural schematic diagram of a transformer winding status online diagnosis system in the second embodiment of the present application, the system comprising: a response voltage acquisition module 301, a relationship curve acquisition module 302, a resonant frequency point acquisition module 303, a resonant voltage value acquisition module 304, a status evaluation factor acquisition module 305 and a diagnosis result acquisition module 306; the response voltage acquisition module 301 is used to inject high-frequency voltage signals of different frequencies into the transformer and obtain the response voltage signal output by the transformer; the relationship curve acquisition module 302 is used to draw a relationship curve between the response voltage and the frequency of the transformer according to the frequency and the response voltage signal; the resonant frequency point acquisition module 303 03 is used to obtain the resonant frequency point of the transformer in the relationship curve; the resonant voltage value acquisition module 304 is used to obtain the resonant voltage value of the transformer according to the resonant frequency point and the preset linear error factor; the state evaluation factor acquisition module 305 is used to obtain the winding state evaluation factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer; the winding state evaluation factor is used to characterize the winding state of the transformer; the diagnosis result acquisition module 306 is used to obtain the winding state diagnosis result of the transformer according to the winding state evaluation factor and the preset threshold value; the winding state diagnosis result includes winding fault and winding no fault.

[0069] The system in this embodiment injects high-frequency voltage signals of different frequencies into the transformer, and obtains the response voltage signal output by the transformer to obtain the relationship curve between the response voltage and the frequency; obtains the resonant frequency point in the relationship curve; obtains the resonant voltage value according to the resonant frequency point and the preset linear error factor; obtains the winding state evaluation factor according to the resonant voltage value and the equivalent inductance value of the transformer; obtains the winding state diagnosis result of the transformer according to the winding state evaluation factor and the preset threshold value. The winding state evaluation factor is obtained according to the obtained resonant voltage value to realize the online detection of the winding state, without shutting down the transformer, thereby ensuring the normal operation and power supply reliability of the transformer, and reducing the maintenance cost and operation risk.

[0070] In a specific embodiment, the third embodiment of the present application provides an online diagnosis device for transformer winding status, including a memory and a processor, wherein 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 injects high-frequency voltage signals of different frequencies into the transformer, and obtains the response voltage signal output by the transformer to obtain a relationship curve between the response voltage and the frequency; obtains the resonant frequency point in the relationship curve; obtains the resonant voltage value according to the resonant frequency point and the preset linear error factor; obtains the winding status evaluation factor according to the resonant voltage value and the equivalent inductance value of the transformer; obtains the winding status diagnosis result of the transformer according to the winding status evaluation factor and the preset threshold. The winding status evaluation factor is obtained according to the obtained resonant voltage value to realize the online detection of the winding status, without shutting down the transformer, thereby ensuring the normal operation and power supply reliability of the transformer, and reducing the maintenance cost and operation risk.

[0071] In a specific embodiment, the fourth embodiment of the present application provides a computer-readable storage medium storing a computer program, and 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 injects high-frequency voltage signals of different frequencies into the transformer, and obtains the response voltage signal output by the transformer to obtain a response voltage and frequency relationship curve; obtains the resonant frequency point in the relationship curve; obtains the resonant voltage value according to the resonant frequency point and the preset linear error factor; obtains the winding state evaluation factor according to the resonant voltage value and the equivalent inductance value of the transformer; obtains the winding state diagnosis result of the transformer according to the winding state evaluation factor and the preset threshold. Obtaining the winding state evaluation factor according to the obtained resonant voltage value realizes online detection of the winding state without shutting down the transformer, thereby ensuring the normal operation and power supply reliability of the transformer, and reducing maintenance costs and operation risks.

[0072] Figure 4The 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.

[0073] 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.

[0074] 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 status online diagnosis method, characterized in that: The method comprises: Injecting high-frequency voltage signals of different frequencies into the transformer, and obtaining a response voltage signal output by the transformer; Draw a curve of the relationship between the response voltage and the frequency of the transformer according to the frequency and the response voltage signal; Obtaining a resonant frequency point of the transformer in the relationship curve; Acquiring a resonant voltage value of the transformer according to the resonant frequency point and a preset linear error factor; Obtaining a winding state evaluation factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer; the winding state evaluation factor is used to characterize the winding state of the transformer; A winding state diagnosis result of the transformer is obtained according to the winding state evaluation factor and a preset threshold value; the winding state diagnosis result includes a winding fault and a winding no fault.

2. The transformer winding status online diagnosis method according to claim 1, characterized in that: The resonant voltage value is obtained using the following formula: Among them, U xz is the resonant voltage value, f i is the i-th resonant frequency point, f j is the jth resonant frequency point, y is the preset linear error factor, η is the integral variable, k1, k2, k3, k4, k5, k6, k7, k8, k9 and k 10 is a constant.

3. The transformer winding status online diagnosis method according to claim 1, characterized in that: The method further comprises: Taking minimization of the preset linear error factor as a goal, optimizing the preset linear error factor using the resonant voltage value and the actual resonant voltage value of the transformer to obtain an optimized linear error factor; The resonant voltage value of the transformer is obtained according to the resonant frequency point and the preset linear error factor, including: Obtaining an optimized resonant voltage value of the transformer according to the resonant frequency point and the optimized linear error factor; Then, obtaining the winding state evaluation factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer includes: A winding state evaluation factor of the transformer is obtained according to the optimized resonant voltage value and the equivalent inductance value of the transformer.

4. The transformer winding status online diagnosis method according to claim 3, characterized in that: The method of optimizing the preset linear error factor by minimizing the preset linear error factor and using the resonant voltage value and the actual resonant voltage value of the transformer to obtain the optimized linear error factor includes: Constructing an objective function of the preset linear error factor according to the resonant voltage value and the actual resonant voltage value of the transformer; Taking minimization of a preset linear error factor as a goal, the preset linear error factor is iteratively optimized using the objective function to obtain the optimized linear error factor.

5. The transformer winding status online diagnosis method according to claim 4, characterized in that: The objective function is obtained using the following formula: Where, f(y) is the objective function, U xz_j is the resonant voltage value corresponding to the jth resonant frequency point, U s_j is the actual resonant voltage value corresponding to the jth resonant frequency point, and N is the number of resonant frequency points.

6. The transformer winding status online diagnosis method according to claim 3, characterized in that: The winding state evaluation factor is obtained by the following formula: Wherein, μ is the winding condition assessment factor, U' xz is the optimized resonant voltage value, c HG is the equivalent capacitance value of the capacitive voltage transformer connected to the transformer, l YQ is the equivalent inductance of the transformer, k 11 , k 12 , k 13 , k 14 , k 15 , k 16 , k 17 , k 18 , k 19 and k 20 is a constant.

7. The transformer winding status online diagnosis method according to claim 1, characterized in that: The step of obtaining a winding state diagnosis result of the transformer according to the winding state evaluation factor and a preset threshold value includes: When the winding state evaluation factor is less than or equal to the preset threshold, the winding state diagnosis result is that the winding has no fault; When the winding state evaluation factor is greater than the preset threshold, the winding state diagnosis result is that the winding fails.

8. A transformer winding status online diagnosis system, characterized in that: The system comprises: a response voltage acquisition module, a relationship curve acquisition module, a resonance frequency point acquisition module, a resonance voltage value acquisition module, a state evaluation factor acquisition module and a diagnosis result acquisition module; The response voltage acquisition module is used to inject high-frequency voltage signals of different frequencies into the transformer and acquire the response voltage signal output by the transformer; The relationship curve acquisition module is used to draw a relationship curve between the response voltage and frequency of the transformer according to the frequency and the response voltage signal; The resonant frequency point acquisition module is used to obtain the resonant frequency point of the transformer in the relationship curve; The resonant voltage value acquisition module is used to acquire the resonant voltage value of the transformer according to the resonant frequency point and a preset linear error factor; The state assessment factor acquisition module is used to obtain the winding state assessment factor of the transformer according to the resonant voltage value and the equivalent inductance value of the transformer; the winding state assessment factor is used to characterize the winding state of the transformer; The diagnosis result acquisition module is used to obtain the winding state diagnosis result of the transformer according to the winding state evaluation factor and the preset threshold; the winding state diagnosis result includes the winding fault and the winding no fault.

9. A transformer winding status online 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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