Resistance-inductance change-based main transformer winding fault diagnosis method

Abstract

The embodiment of the invention discloses a main transformer winding fault diagnosis method based on resistance-inductance change, and the method comprises the steps: measuring transformer winding injection signals and output signals under different injection resistance inductances, obtaining resistance-inductance distinguishing amplitudes, obtaining different frequency response curve weights, and obtaining different frequency response curve weights; comprise the weight when only resistance is considered, the weight when only inductance is considered, and the weight when the resistance and the inductance are comprehensively considered; according to the resistance-inductance distinguishing amplitude and the different frequency response curve weights, further calculating a response signal linear correlation strength index of the frequency response curve when only resistance, only inductance and comprehensive resistance and inductance are considered; transformer winding fault judgment factors are calculated according to the transformer winding diagnosis characteristic indexes, and transformer winding fault judgment is carried out according to the transformer winding fault judgment factors; according to the method, the transformer winding fault can be accurately and effectively judged, the judgment process is simplified, and non-professionals can easily master the method.

Description

Technical Field

[0001] The present invention relates to the technical field of transformer winding fault diagnosis, and in particular to a main transformer winding fault diagnosis method based on resistance and inductance changes. Background Art

[0002] Transformer winding fault diagnosis is extremely valuable in power systems and is a key component in ensuring the safety and stability of system operations. As a key node in the power grid, the health of the transformer directly determines the quality and stability of power transmission. However, due to long-term exposure to complex operating environments, transformer windings are susceptible to multiple stresses, including electromagnetic forces, mechanical vibration, short-circuit shocks, and environmental factors. These stresses can lead to insulation degradation, mechanical deformation, displacement, and loosening. As the fault progresses, the transformer's electrical performance is severely affected. In severe cases, this can even cause grid failures or power outages, leading to user-side outages, economic losses, and significantly increased equipment repair costs. Therefore, timely and accurate diagnosis of transformer winding faults and the implementation of preventive measures are crucial tasks in power system maintenance.

[0003] Frequency Response Analysis (FRA), as an advanced non-invasive detection method, has been widely used in the field of winding fault diagnosis. The basic principle of FRA is to inject low-voltage signals of different frequencies at both ends of the transformer winding and then measure the winding's response characteristics to these signals. The electrical and mechanical structure of the winding determines its specific frequency response curve. When a winding fault occurs, such as winding displacement, looseness, or insulation degradation, the winding's electrical parameters such as resistance, inductance, and capacitance will undergo subtle changes, resulting in offset, distortion, or peak changes in the frequency response curve. Therefore, by analyzing the frequency response curve, it is possible to identify whether a winding fault exists, the type of fault, and the fault location.

[0004] However, existing frequency response analysis usually requires users to have professional electrical knowledge, which makes it difficult for non-professionals to understand and apply it. Summary of the Invention

[0005] The main purpose of the present invention is to provide a main transformer winding fault diagnosis method based on resistance-inductance change, which can accurately and effectively judge transformer winding faults, simplify the judgment process, and make it easy for non-professionals to master it.

[0006] To achieve the above objectives, the present application provides, in a first aspect, a method for diagnosing a main transformer winding fault based on resistance-inductance changes, the method comprising:

[0007] Measure the transformer winding injection signal and output signal under different injection resistance and inductance conditions to obtain resistance-inductance distinction amplitudes, wherein the resistance-inductance distinction amplitudes include the amplitude of the mth data point of the lth group of frequency response curves when only resistance is considered, the amplitude of the mth data point of the kth group of frequency response curves when only inductance is considered, and the amplitude of the mth data point of the pqth group of frequency response curves when both resistance and inductance are comprehensively considered, where l, k, p, and q are positive integers;

[0008] Obtain weights for different frequency response curves, including the weight when only resistance is considered, the weight when only inductance is considered, and the weight when both resistance and inductance are considered;

[0009] Obtaining a transformer winding diagnostic characteristic index according to the resistance-inductance distinction amplitude and the weights of the different frequency response curves;

[0010] A transformer winding fault judgment factor is calculated according to the transformer winding diagnosis characteristic index, and a transformer winding fault judgment is performed according to the transformer winding fault judgment factor.

[0011] Optionally, measuring the transformer winding injection signal and output signal under different injection resistance and inductance to obtain the resistance-inductance distinction amplitude includes:

[0012] The variable inductor and variable resistor are controlled to be in a short-circuit state. Then, a computer is used to generate excitation signals of different frequencies through a signal generator. The excitation signals are injected into the transformer windings, flow through the low-voltage winding, the medium-voltage winding, and the high-voltage winding, and then flow out of the transformer. The output response is measured, and the input and output measurements are stopped. The change value of the variable inductor is controlled to be L va =[L1 L2…L n ], the change value of the variable resistor is R va =[R1 R2…R n ], L n and R n Respectively represent the inductance and resistance values ​​injected into the nth measurement, where L n >L n-1 …>L1, R n >R n-1 …>R1;

[0013] Repeat the above measurement steps to obtain n×n groups of frequency response curves, including the frequency response curves considering only resistance, only inductance, and comprehensive consideration of resistance and inductance, respectively. l =[x Rl1 x Rl2 … x Rlm ]、F k =[x=y Lk1 y Lk2 …y Lkm ]、F pq=[z pq1 z pq2 … z pqm ], where x Rlm represents the amplitude of the mth data point of the frequency response curve of the first group when only the resistance is considered, y Lkm represents the amplitude of the mth data point of the kth group of frequency response curves when only the inductance is considered, z pqm It represents the amplitude of the mth data point of the frequency response curve of the pqth group when the resistance and inductance are comprehensively considered.

[0014] Optionally, obtaining weights of different frequency response curves includes:

[0015] The resistance-inductance distinction weight is calculated according to the following formula:

[0016]

[0017] Among them, w Rl 、w Lk 、w pq They represent the weight when only the resistance is considered, the weight when only the inductance is considered, and the weight when the resistance and inductance are considered comprehensively, α and β represent adjustment parameters, ε and The default positive number.

[0018] Optionally, obtaining a transformer winding diagnostic characteristic index according to the resistance-inductance distinction amplitude and the weights of the different frequency response curves includes:

[0019] The composite resistance-inductance frequency characteristic curve is calculated according to the following formula:

[0020]

[0021] Among them, Q Rm 、W Lm 、E RLm They represent the amplitude of the mth data point of the frequency response curve when only resistance, only inductance, and resistance and inductance are considered respectively;

[0022] The linear correlation strength index of the response signal is calculated according to the composite resistance-inductance frequency characteristic curve.

[0023] Optionally, calculating the response signal linear correlation strength index according to the composite resistance-inductance frequency characteristic curve includes:

[0024] The linear correlation strength index of the response signal is calculated using the following formula:

[0025]

[0026] Optionally, calculating the transformer winding fault judgment factor based on the transformer winding diagnosis characteristic index includes:

[0027] Calculating the transformer winding fault judgment factor according to the following formula:

[0028] ν = 0.8XR 2 + 1.2XC·XZ + 0.5e 0.05XR+0.03XC+0.07XZ + 1.5log(1 + |XR - XC|).

[0029] Optionally, judging the transformer winding fault according to the transformer winding fault judgment factor includes:

[0030] If ν ≥ T, it is judged that there is a fault in the transformer winding;

[0031] If ν < T, it is judged that there is no fault in the transformer winding, where T is a constant related to the transformer model, winding signal injection method, and external equipment.

[0032] The second aspect of the present application provides a main transformer winding fault diagnosis device based on the change of resistance and inductance, including:

[0033] A measurement module for measuring the injected signal and output signal of the transformer winding under different injected resistances and inductances to obtain the resistance and inductance discrimination amplitude, where the resistance and inductance discrimination amplitude includes the amplitude of the mth data point of the lth group of frequency response curves when only considering the resistance, the amplitude of the mth data point of the kth group of frequency response curves when only considering the inductance, and the amplitude of the mth data point of the pqth group of frequency response curves when comprehensively considering the resistance and inductance. Here, l, k, p, and q are positive integers;

[0034] A weight calculation module for obtaining the weights of different frequency response curves, including the weight when only considering the resistance, the weight when only considering the inductance, and the weight when comprehensively considering the resistance and inductance;

[0035] An index calculation module for obtaining the transformer winding diagnosis characteristic index according to the resistance and inductance discrimination amplitude and the weights of different frequency response curves;

[0036] A judgment module for calculating the transformer winding fault judgment factor according to the transformer winding diagnosis characteristic index and judging the transformer winding fault according to the transformer winding fault judgment factor.

[0037] The third aspect of the present application provides an electronic device, including a memory and a processor. When the computer program stored in the memory is executed by the processor, the processor executes the steps of the first aspect and any possible implementation manner thereof.

[0038] A fourth aspect 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 described in the first aspect.

[0039] The present application provides a main transformer winding fault diagnosis method based on resistance-inductance changes. By measuring the transformer winding injection signal and output signal under different injection resistance and inductance, the resistance-inductance distinction amplitude is obtained, and the weights of different frequency response curves are obtained, including the weight when only resistance is considered, the weight when only inductance is considered, and the weight when resistance and inductance are comprehensively considered; based on the resistance-inductance distinction amplitude and the weights of the different frequency response curves, the transformer winding diagnostic characteristic index is obtained; based on the transformer winding diagnostic characteristic index, the transformer winding fault judgment factor is calculated, and the transformer winding fault judgment is performed based on the transformer winding fault judgment factor; this method considers the main transformer winding fault diagnosis based on resistance-inductance changes, while improving the fault diagnosis sensitivity, simplifying the judgment process, making it easy for non-professionals to master. In addition, it can accurately identify the state of the winding and determine whether there is a fault, thereby providing effective support for the safe and stable operation of the transformer and power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any creative work.

[0041] in:

[0042] Figure 1 A flow chart of a method for diagnosing a main transformer winding fault based on resistance-inductance changes provided by an embodiment of the present application;

[0043] Figure 2 A flow chart of another method for diagnosing a main transformer winding fault based on resistance-inductance changes provided by an embodiment of the present application;

[0044] Figure 3 A schematic structural diagram of a main transformer winding fault diagnosis device based on resistance and inductance changes provided by an embodiment of the present application;

[0045] Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0047] The terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish between different objects, not to describe a particular order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0048] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0049] The resistance and inductance changes involved in the embodiments of the present application mainly refer to changes in the resistance and inductance of the transformer, and in experiments, control can be achieved based on variable resistance and variable inductance.

[0050] The method in the embodiment of the present application mainly involves obtaining a frequency response curve of a transformer winding connected to different resistance-inductance loads on the outside of the transformer, then calculating a composite resistance-inductance frequency response curve by assigning response weights to the frequency response curves when only resistance, only inductance, and resistance and inductance are considered comprehensively, further calculating a response signal linear correlation strength index of the frequency response curves when only resistance, only inductance, and resistance and inductance are considered comprehensively, and finally determining whether a transformer winding fault occurs by calculating a transformer winding fault judgment factor.

[0051] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0052] See also Figure 1 , is a flow chart of a main transformer winding fault diagnosis method based on resistance-inductance change provided by an embodiment of the present application, such as Figure 1 As shown, the method includes:

[0053] 101. Measure the transformer winding injection signal and output signal under different injection resistance and inductance conditions to obtain resistance-inductance distinction amplitudes, where the resistance-inductance distinction amplitudes include the amplitude of the mth data point of the lth group of frequency response curves when only resistance is considered, the amplitude of the mth data point of the kth group of frequency response curves when only inductance is considered, and the amplitude of the mth data point of the pqth group of frequency response curves when both resistance and inductance are considered, where l, k, p, and q are positive integers.

[0054] The executor of the method in the embodiment of the present application can be a main transformer winding fault diagnosis device based on resistance-inductance changes. In practical applications, it can be implemented using terminal equipment, such as a computer, and mainly involves signal control and data analysis and calculation processes.

[0055] Specifically, different injection resistance and inductance values ​​can be set by adjusting the transformer windings or using external resistors. A signal generator generates a signal of a specific frequency and amplitude and injects it into the transformer windings. During measurement, an oscilloscope or spectrum analyzer can be used at the transformer output to measure parameters such as the amplitude, frequency, and phase of the output signal. For each injection resistance and inductance value, the corresponding injection and output signal characteristics can be recorded.

[0056] In an optional implementation, the above step 101 includes:

[0057] The variable inductor and variable resistor are controlled to be in a short-circuit state. Then, a computer is used to generate excitation signals of different frequencies through a signal generator. The excitation signals are injected into the transformer windings, flow through the low-voltage winding, the medium-voltage winding, and the high-voltage winding, and then flow out of the transformer. The output response is measured, and the input and output measurements are stopped. The change value of the variable inductor is controlled to be L va =[L1 L2…L n ], the change value of the variable resistor is R va =[R1 R2…R n ], L n and R n Respectively represent the inductance and resistance values ​​injected into the nth measurement, where L n >L n-1 …>L1, R n >R n-1 …>R1;

[0058] Repeat the above measurement steps to obtain n×n The frequency response curves of the group include the frequency response curves of considering only resistance, considering only inductance, and considering resistance and inductance comprehensively, respectively. l =[x Rl1 x Rl2 …x Rlm ]、F k =[x=y Lk1 yLk2 …y Lkm ]、F pq =[z pq1 z pq2 …z pqm ], where x Rlm It represents the amplitude of the mth data point of the frequency response curve of the first group when only the resistance is considered. Lkm It represents the amplitude of the mth data point of the kth group frequency response curve when only the inductance is considered. pqm represents the amplitude of the mth data point of the pqth group of frequency response curves when considering the resistance and inductance, where l, k, p, and q range from [1, 2, 3, …, n].

[0059] 102. Obtain weights for different frequency response curves, including the weight when only resistance is considered, the weight when only inductance is considered, and the weight when both resistance and inductance are considered.

[0060] Specifically, the embodiments of the present application are mainly divided into three situations: considering only resistance, considering only inductance, and considering both resistance and inductance. Three types of weights are calculated here accordingly.

[0061] In an optional implementation, the obtaining of weights of different frequency response curves includes:

[0062] The resistance-inductance distinction weight is calculated according to the following formula:

[0063]

[0064] Among them, w Rl 、w Lk 、w pq They represent the weight when only resistance is considered, the weight when only inductance is considered, and the weight when resistance and inductance are considered comprehensively, α and β represent adjustment parameters, ε and The default positive number.

[0065] ε、 It can be a small positive number to avoid the denominator being zero. That is, these decimals are added when calculating the reciprocal of the absolute value to ensure numerical stability.

[0066] w Rl This formula calculates the l (resistance) related weight. The whole fraction represents R l The relative importance of R j The sum of the relative importance of l The normalized weight of .

[0067] w Lk This formula is consistent with w RlSimilar, but it is for L k (Inductance) Calculation weight.

[0068] w pq This formula calculates the weight of the resistance and inductance combination. α and β are the weight adjustment parameters used to adjust R l and L k The relative importance of the combination. The numerator is R l and L k The logarithm of the combination, the denominator is all R j and L i The sum of the logarithmic values ​​of the combination. This weight can be used to measure the importance of the resistance and inductance combination in the entire data set.

[0069] 103. Obtain a transformer winding diagnostic characteristic index based on the resistance-inductance distinction amplitude and the weights of the different frequency response curves.

[0070] Specifically, based on the data obtained in the above steps, the transformer winding diagnostic characteristic index can be calculated. Accordingly, the calculated index is divided into three cases: considering only resistance, considering only inductance, and considering both resistance and inductance. It mainly includes two steps:

[0071] (1) Calculate the composite resistance-inductance frequency characteristic curve;

[0072] (2) Calculate the linear correlation strength index of the response signal.

[0073] In an optional embodiment, obtaining the transformer winding diagnostic characteristic index according to the resistance-inductance distinction amplitude and the weights of the different frequency response curves includes:

[0074] The above composite resistance-inductance frequency characteristic curve is calculated according to the following formula:

[0075]

[0076] Among them, Q Rm 、W Lm 、E RLm They represent the amplitude of the mth data point of the frequency response curve when only resistance, only inductance, and resistance and inductance are considered respectively;

[0077] The linear correlation strength index of the response signal is calculated based on the composite resistance-inductance frequency characteristic curve.

[0078] Further optionally, the calculation of the linear correlation strength index of the response signal according to the composite resistance-inductance frequency characteristic curve includes:

[0079] The linear correlation strength index of the above response signal is calculated using the following formula:

[0080]

[0081] The linear correlation strength index of the response signal can be used to analyze the linear relationship between two signals. Specifically, the variables and operations involved in the formula are as follows:

[0082] Q Ri , Q i 、W Li , WO i 、E RLi EO i : These are the values ​​of the different signals at the i-th data point.

[0083] The constants can be set or characterized as needed, such as 1.414, 2.75, 1.1, etc. These constants can be used to adjust the weights in the formula.

[0084] The specific meaning of the formula is as follows:

[0085] XR: Calculating Q Ri and Q i The linear correlation strength between them is used to obtain the linear correlation strength index of the response signal when only the resistance is considered.

[0086] XL: Calculate W Li and WO i The linear correlation strength between them is calculated to obtain the linear correlation strength index of the response signal when only the inductance is considered.

[0087] XZ: Calculate E RLi and EO i The linear correlation strength between them is calculated to obtain the linear correlation strength index of the response signal when the resistance and inductance are comprehensively considered.

[0088] 104. Calculate a transformer winding fault judgment factor based on the transformer winding diagnostic characteristic index, and perform transformer winding fault judgment based on the transformer winding fault judgment factor.

[0089] After obtaining the linear correlation strength indicators of the response signals in the above three aspects, the transformer winding fault judgment factor can be further calculated for transformer winding fault judgment. The transformer winding fault judgment factor calculation formula can be set as needed.

[0090] In an optional embodiment, the calculation of the transformer winding fault judgment factor based on the transformer winding diagnostic characteristic index includes:

[0091] The above transformer winding fault judgment factor is calculated according to the following formula:

[0092] ν=0.8XR 2 +1.2XC·XZ+0.5e0.05XR+0.03XC+0.07XZ +1.5 log(1 + |XR - XC|).

[0093] Further optionally, the above-mentioned determination of transformer winding faults based on the above-mentioned transformer winding fault determination factor includes:

[0094] If ν ≥ T, it is determined that there is a fault in the transformer winding;

[0095] If ν < T, it is determined that there is no fault in the transformer winding, where T is a constant related to the transformer model, winding signal injection method, and external equipment, and can be set as needed.

[0096] To more clearly show the method in the embodiments of the present application, reference can be made to Figure 2 , Figure 2 which is a schematic flow diagram of another main transformer winding fault diagnosis method based on the change of resistance and inductance provided by the embodiments of the present application. As Figure 2 shown, the method mainly includes:

[0097] Obtain the frequency response curves of the transformer winding under different externally connected resistance-inductance loads of the transformer;

[0098] Calculate the response weights of the frequency response curves when only considering the resistance, the response weights of the frequency response curves when only considering the inductance, and the response weights of the frequency response curves when comprehensively considering the resistance and inductance;

[0099] Calculate the optimized frequency response curves when only considering the resistance, the optimized frequency response curves when only considering the inductance, and the optimized frequency response curves when comprehensively considering the resistance and inductance;

[0100] Calculate the linear correlation strength indexes of the response signals when only considering the resistance, the linear correlation strength indexes of the response signals when only considering the inductance, and the linear correlation strength indexes of the response signals when comprehensively considering the resistance and inductance;

[0101] Calculate the transformer winding fault determination factor based on the above indexes;

[0102] Judge whether the transformer winding has a fault according to the transformer winding fault determination factor.

[0103] It can be seen that in the embodiments of the present application, first, the frequency response curves of the transformer winding under different externally connected resistance-inductance loads of the transformer can be obtained through computer control; then, by assigning response weights to the frequency response curves when only considering the resistance, only considering the inductance, and comprehensively considering the resistance and inductance, the composite resistance-inductance frequency response curve is calculated; further, the linear correlation strength indexes of the response signals of the frequency response curves when only considering the resistance, only considering the inductance, and comprehensively considering the resistance and inductance are calculated; finally, it is judged whether the winding has a fault by calculating the transformer winding fault determination factor.

[0104] The method in this application's embodiments specifically addresses main transformer winding fault diagnosis based on resistance-inductance changes. This method improves fault diagnosis sensitivity while simplifying the diagnostic process, making it easily accessible to non-professionals. Furthermore, it accurately identifies the winding status and determines whether a fault exists, effectively supporting the safe and stable operation of transformers and power systems.

[0105] Based on the description of the aforementioned method embodiment, an embodiment of the present application further provides a main transformer winding fault diagnosis device based on resistance-inductance changes.

[0106] Figure 3 This is a schematic diagram of the structure of a main transformer winding fault diagnosis device based on resistance and inductance changes provided by an embodiment of the present application. Figure 3 As shown, the main transformer winding fault diagnosis device 300 based on resistance and inductance change includes:

[0107] The measurement module 310 is configured to measure the transformer winding injection signal and output signal under different injection resistance and inductance conditions to obtain resistance-inductance distinction amplitudes, where the resistance-inductance distinction amplitudes include the amplitude of the mth data point of the lth group of frequency response curves when only resistance is considered, the amplitude of the mth data point of the kth group of frequency response curves when only inductance is considered, and the amplitude of the mth data point of the pqth group of frequency response curves when both resistance and inductance are considered, where l, k, p, and q are positive integers.

[0108] The weight calculation module 320 is used to obtain weights of different frequency response curves, including the weight when only resistance is considered, the weight when only inductance is considered, and the weight when both resistance and inductance are considered;

[0109] An index calculation module 330 is configured to obtain a transformer winding diagnostic characteristic index based on the resistance-inductance distinction amplitude and the weights of the different frequency response curves;

[0110] The judgment module 340 is configured to calculate a transformer winding fault judgment factor based on the transformer winding diagnosis characteristic index, and perform transformer winding fault judgment based on the transformer winding fault judgment factor.

[0111] Understandably, Figure 3 The relevant contents of each module in the above method embodiment have been described in detail, and the details can be referred to the contents of the method embodiment; Figure 3 The main transformer winding fault diagnosis device 300 based on resistance-inductance change can be performed as follows: Figure 1 or Figure 2 Any steps in the illustrated embodiment will not be described in detail here.

[0112] In one embodiment of the present application, an electronic device is also provided. Figure 4, Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 4 As shown, the electronic device 400 includes a processor 401 and a memory 402. The memory 402 stores a computer program. When the computer program is executed by the processor 401, the following operations are performed: Figure 1 or Figure 2 The electronic device 400 may further include an input / output device, etc. In a specific embodiment, the electronic device may be a terminal device, etc.

[0113] In one embodiment, a computer-readable storage medium is further provided. The computer-readable storage medium stores a computer program. When the computer program is executed by the processor 401, the processor 401 executes any step in the above method embodiment.

[0114] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0115] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0116] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A main transformer winding fault diagnosis method based on resistance and inductance changes, characterized in that: The method includes: Measuring the injection signal and output signal of the transformer winding under different injection resistances and inductances to obtain the resistance and inductance discrimination amplitude values. The resistance and inductance discrimination amplitude values include the amplitude value of the m-th data point of the l-th group of frequency response curves when only considering resistance, the amplitude value of the m-th data point of the k-th group of frequency response curves when only considering inductance, and the amplitude value of the m-th data point of the pq-th group of frequency response curves when comprehensively considering resistance and inductance, where l, k, p, and q are positive integers; Obtaining different frequency response curve weights, including the weight when only considering resistance, the weight when only considering inductance, and the weight when comprehensively considering resistance and inductance; Obtaining the transformer winding diagnosis characteristic index according to the resistance and inductance discrimination amplitude values and the different frequency response curve weights; Calculating the transformer winding fault judgment factor according to the transformer winding diagnosis characteristic index, and performing transformer winding fault judgment according to the transformer winding fault judgment factor.

2. The main transformer winding fault diagnosis method based on resistance-inductance change according to claim 1 is characterized in that: The measuring the injection signal and output signal of the transformer winding under different injection resistances and inductances to obtain the resistance and inductance discrimination amplitude values includes: The variable inductor and the variable resistor are controlled to be in a short-circuit state, and then a computer is used to pass through a signal generator to generate excitation signals of different frequencies. The excitation signal is injected into the transformer winding, flows through the low-voltage winding, the medium-voltage winding, and the high-voltage winding, and then flows out of the transformer. The output response is measured, and the input and output measurements are stopped. The change value of the variable inductor is controlled to be L va =[L1 L2 … L n ], the change value of the variable resistor is R va =[R1 R2 … R n ], L n and R n Respectively represent the inductance and resistance values ​​injected into the nth measurement, where L n >L n-1 …>L1, R n >R n-1 …>R1; Repeat the above measurement steps to obtain n×n groups of frequency response curves, including the frequency response curves considering only resistance, only inductance, and comprehensive consideration of resistance and inductance, respectively. l =[x Rl1 x Rl2 … x Rlm ]、F k =[x=y Lk1 y Lk2 … y Lkm ]、F pq =[z pq1 z pq2 … z pqm ], where x Rlm represents the amplitude of the mth data point of the frequency response curve of the lth group when only the resistance is considered, y Lkm represents the amplitude of the mth data point of the kth group of frequency response curves when only the inductance is considered, z pqm It represents the amplitude of the mth data point of the frequency response curve of the pqth group when the resistance and inductance are comprehensively considered.

3. The main transformer winding fault diagnosis method based on resistance-inductance change according to claim 2 is characterized in that: The obtaining different frequency response curve weights includes: Calculating the resistance and inductance discrimination weights according to the following formula: Among them, w Rl 、w Lk 、w pq They respectively represent the weight when only the resistance is considered, the weight when only the inductance is considered, and the weight when the resistance and inductance are considered comprehensively, α and β represent adjustment parameters, ε, The default value is a positive number.

4. The main transformer winding fault diagnosis method based on resistance-inductance change according to claim 3 is characterized in that: The obtaining the transformer winding diagnosis characteristic index according to the resistance and inductance discrimination amplitude values and the different frequency response curve weights includes: Calculating the composite resistance and inductance frequency characteristic curve according to the following formula: Among them, Q Rm , W Lm 、E RLm They represent the amplitude of the mth data point of the frequency response curve when only resistance, only inductance, and resistance and inductance are considered respectively; Calculating the linear correlation strength index of the response signal according to the composite resistance and inductance frequency characteristic curve.

5. The main transformer winding fault diagnosis method based on resistance-inductance change according to claim 4 is characterized in that: The calculating the linear correlation strength index of the response signal according to the composite resistance and inductance frequency characteristic curve includes: Calculating the linear correlation strength index of the response signal by using the following formula:

6. The main transformer winding fault diagnosis method based on resistance-inductance change according to claim 5 is characterized in that: The calculating the transformer winding fault judgment factor according to the transformer winding diagnosis characteristic index includes: Calculating the transformer winding fault judgment factor according to the following formula: ν=0.8XR 2 +1.2XC·XZ+0.5e 0.05XR+0.03XC+0.07XZ +1.5log(1+|XR-XC|)。 7. The main transformer winding fault diagnosis method based on resistance-inductance change according to claim 6 is characterized in that: The performing transformer winding fault judgment according to the transformer winding fault judgment factor includes: If ν≥T, it is determined that there is a fault in the transformer winding; If ν<T, it is determined that there is no fault in the transformer winding, where T is a constant related to the transformer model, winding signal injection method, and external equipment.

8. A main transformer winding fault diagnosis device based on resistance and inductance changes, characterized in that: Includes: A measuring module for measuring the injection signal and output signal of the transformer winding under different injection resistances and inductances to obtain the resistance and inductance discrimination amplitude values. The resistance and inductance discrimination amplitude values include the amplitude value of the m-th data point of the l-th group of frequency response curves when only considering resistance, the amplitude value of the m-th data point of the k-th group of frequency response curves when only considering inductance, and the amplitude value of the m-th data point of the pq-th group of frequency response curves when comprehensively considering resistance and inductance, where l, k, p, and q are positive integers; A weight calculation module for obtaining different frequency response curve weights, including the weight when only considering resistance, the weight when only considering inductance, and the weight when comprehensively considering resistance and inductance; An index calculation module for obtaining the transformer winding diagnosis characteristic index according to the resistance and inductance discrimination amplitude values and the different frequency response curve weights; A judgment module for calculating the transformer winding fault judgment factor according to the transformer winding diagnosis characteristic index and performing transformer winding fault judgment according to the transformer winding fault judgment factor.

9. An electronic device, characterized in that: The method comprises 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 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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