Transformer winding fault diagnosis and relay protection interference evaluation method and device, medium and equipment

Abstract

The invention discloses a transformer winding fault diagnosis and relay protection interference assessment method and device, a medium and equipment, and the method comprises the steps: obtaining an amplitude-frequency response curve and a phase-frequency response curve of a transformer in a preset frequency band, calculating the Euclidean distance in each region frequency band, and obtaining the Euclidean distances of a plurality of amplitude-frequency regions and phase-frequency regions. And according to the Euclidean distance calculation, the Euclidean distance ratio is fused, and whether the transformer winding has a fault is judged. Meanwhile, on the premise that the transformer winding has a fault, an influence evaluation factor of relay protection is calculated in combination with online operation data, and if the factor is smaller than a preset threshold value, it can be confirmed that a fault judgment result is accurate. According to the method, by considering the interference of relay protection on frequency response measurement, the problem that the interference of relay protection on the fault monitoring result of the transformer winding is not fully considered in the prior art is solved, so that the accuracy of fault judgment is ensured, and the monitoring result is prevented from being influenced by misoperation or hysteresis of relay protection.

Description

Technical Field

[0001] The present invention relates to the technical field of power equipment fault diagnosis, and in particular to a transformer winding fault diagnosis and relay protection interference assessment method, device, medium and equipment. Background Art

[0002] Frequency response analysis is widely used in fault diagnosis of transformer windings, cores, and tap changers. The transformer can be regarded as a complex network composed of parameters such as inductance, resistance, capacitance, and conductance. When the state of each component of the transformer changes, its equivalent circuit parameters will also change, which will lead to changes in frequency response. These changes can be used to infer the fault state of the transformer.

[0003] However, relay protection will automatically cut off the transformer circuit when a fault occurs, which may interfere with the measurement of frequency response and thus affect the accuracy of fault diagnosis. However, at present, the relevant frequency response analysis standards do not fully consider the impact of relay protection on transformer winding fault monitoring. Summary of the invention

[0004] Based on this, it is necessary to provide a transformer winding fault diagnosis and relay protection interference assessment method, device, medium and equipment to solve the problem that the existing technology does not fully consider the impact of relay protection on transformer winding fault monitoring.

[0005] A transformer winding fault diagnosis and relay protection interference assessment method is applied to a transformer winding online monitoring system. The transformer winding online monitoring system includes a transformer and relay protection. The method includes:

[0006] Obtaining the amplitude-frequency response curve and phase-frequency response curve of the transformer within a preset frequency band;

[0007] The preset frequency band is evenly divided into a plurality of regional frequency bands, and the Euclidean distance of the amplitude-frequency response curve in each regional frequency band is calculated respectively to obtain a plurality of amplitude-frequency regional Euclidean distances, and the Euclidean distance of the phase-frequency response curve in each regional frequency band is calculated to obtain a plurality of phase-frequency regional Euclidean distances;

[0008] Calculating a ratio of fused Euclidean distances according to the multiple Euclidean distances in amplitude-frequency regions and the multiple Euclidean distances in phase-frequency regions, and determining that a transformer winding is faulty if the ratio of the fused Euclidean distances falls within a preset distance interval;

[0009] Under the premise that there is a fault in the transformer winding, the online operation data of the transformer is obtained, and the impact evaluation factor of the relay protection is calculated based on the online operation data of the transformer. If the impact evaluation factor is less than the preset impact threshold, the judgment result that there is a fault in the transformer winding is accurate.

[0010] In one embodiment, the Euclidean distance of the amplitude-frequency response curve in each regional frequency band is calculated to obtain a plurality of amplitude-frequency regional Euclidean distances, and the Euclidean distance of the phase-frequency response curve in each regional frequency band is calculated to obtain a plurality of phase-frequency regional Euclidean distances, which are expressed as:

[0011]

[0012] In the above formula, X M is the Euclidean distance of the amplitude-frequency region in any regional frequency band; V1 is the amplitude sequence of the fingerprint amplitude-frequency response curve in any regional frequency band; V2 is the amplitude sequence of the amplitude-frequency response curve after the fault in the same regional frequency band of V1; X P is the phase-frequency regional Euclidean distance of any regional frequency band; P1 is the phase sequence of the fingerprint phase-frequency response curve in any regional frequency band; P2 is the phase sequence of the phase-frequency response curve after the fault in the same regional frequency band of P1.

[0013] In one embodiment, the ratio of the fused Euclidean distance calculated based on the Euclidean distances in the multiple amplitude-frequency regions and the Euclidean distances in the multiple phase-frequency regions is expressed as:

[0014]

[0015] In the above formula, X MMRI is the ratio of the fused Euclidean distance; X Mmax is the maximum value of the Euclidean distances of the multiple amplitude-frequency regions; Mmin is the minimum value of the Euclidean distances of the multiple amplitude-frequency regions; Pmax is the maximum value of the Euclidean distances of the multiple phase frequency regions; Pmin is the minimum value of the Euclidean distances of the multiple phase-frequency regions.

[0016] In one embodiment, if the ratio of the fused Euclidean distances falls within a preset distance interval, it is determined that a transformer winding has a fault, including:

[0017] If the ratio of the fused Euclidean distances falls within a preset first distance interval, it is determined that an axial displacement fault exists in the transformer winding;

[0018] If the ratio of the fused Euclidean distances falls within a preset second distance interval, it is determined that a radial deformation fault or a mixed fault exists in the transformer winding.

[0019] In one of the embodiments, on the premise of determining that the transformer winding has a radial deformation fault or a mixed fault, the method further includes:

[0020] Calculate the offset area ratio of the amplitude-frequency response curve, expressed as:

[0021]

[0022] In the above formula, S OA is the proportion of the offset area; V1(i) is the amplitude of the i-th point of the fingerprint amplitude-frequency response curve; V2(i) is the amplitude of the i-th point of the amplitude-frequency response curve after the fault; f(i) is the frequency corresponding to the i-th point;

[0023] If the offset area ratio is less than or equal to the preset ratio threshold, it is determined that the transformer winding has a radial deformation fault; if the offset area ratio is greater than the preset ratio threshold, it is determined that the transformer winding has a mixed fault.

[0024] In one embodiment, the influence evaluation factor of relay protection is calculated based on the online operation data of the transformer, and is expressed as:

[0025]

[0026] In the above formula, I d is the differential current; I dz is the setting value of relay protection current; T e is the ambient temperature; T c is the ambient temperature; is the phase angle difference between voltage and current; θ is the internal angle of the power direction relay.

[0027] A transformer winding fault diagnosis and relay protection interference assessment device is applied to a transformer winding online monitoring system. The transformer winding online monitoring system includes a transformer and relay protection. The transformer winding fault diagnosis and relay protection interference assessment device includes:

[0028] An acquisition module, used to acquire an amplitude-frequency response curve and a phase-frequency response curve of the transformer within a preset frequency band;

[0029] A Euclidean distance calculation module, used for evenly dividing the preset frequency band into a plurality of regional frequency bands, and respectively calculating the Euclidean distance of the amplitude-frequency response curve in each regional frequency band to obtain a plurality of amplitude-frequency regional Euclidean distances, and calculating the Euclidean distance of the phase-frequency response curve in each regional frequency band to obtain a plurality of phase-frequency regional Euclidean distances;

[0030] A fault diagnosis module, used for calculating a ratio of fused Euclidean distances according to the multiple Euclidean distances in amplitude-frequency regions and the multiple Euclidean distances in phase-frequency regions, and determining that a transformer winding has a fault if the ratio of the fused Euclidean distances falls within a preset distance interval;

[0031] The impact assessment module is used to obtain the online operation data of the transformer under the premise that there is a fault in the transformer winding, and calculate the impact assessment factor of the relay protection based on the online operation data of the transformer. If the impact assessment factor is less than a preset impact threshold, the judgment result that there is a fault in the transformer winding is accurate.

[0032] In one embodiment, the Euclidean distance calculation module is specifically used to calculate:

[0033]

[0034] In the above formula, X M is the Euclidean distance of the amplitude-frequency region in any regional frequency band; V1 is the amplitude sequence of the fingerprint amplitude-frequency response curve in any regional frequency band; V2 is the amplitude sequence of the amplitude-frequency response curve after the fault in the same regional frequency band of V1; X P is the phase-frequency regional Euclidean distance of any regional frequency band; P1 is the phase sequence of the fingerprint phase-frequency response curve in any regional frequency band; P2 is the phase sequence of the phase-frequency response curve after the fault in the same regional frequency band of P1.

[0035] A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the processor executes the steps of the above-mentioned transformer winding fault diagnosis and relay protection interference assessment method.

[0036] A terminal device includes 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 above-mentioned transformer winding fault diagnosis and relay protection interference assessment method.

[0037] The present invention provides a method, device, medium and equipment for transformer winding fault diagnosis and relay protection interference assessment. By obtaining the amplitude-frequency response curve and phase-frequency response curve of the transformer in a preset frequency band, and calculating the Euclidean distance in each regional frequency band respectively, the Euclidean distances of multiple amplitude-frequency regions and phase-frequency regions are obtained. Then, based on these Euclidean distance calculations, the ratio of the Euclidean distances is integrated to determine whether the transformer winding is faulty. At the same time, under the premise of a transformer winding fault, the influence evaluation factor of the relay protection is calculated in combination with the online operation data. If the factor is less than the preset threshold, it can be confirmed that the fault judgment result is accurate. This method particularly solves the problem that the prior art does not fully consider the interference that relay protection may cause to the transformer winding fault monitoring results, thereby ensuring the accuracy of fault judgment and avoiding the monitoring results being affected by false operation or hysteresis of relay protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention 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 invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] in:

[0040] Figure 1 It is a flow chart of transformer winding fault diagnosis and relay protection interference assessment method;

[0041] Figure 2 It is a schematic diagram of the transformer winding online monitoring system;

[0042] Figure 3 It is a schematic diagram of the structure of the transformer winding fault diagnosis and relay protection interference assessment device;

[0043] Figure 4 This is a structural block diagram of the terminal equipment. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings 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 units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0046] 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.

[0047] like Figure 1 As shown, Figure 1 The present invention is a flow chart of a transformer winding fault diagnosis and relay protection interference assessment method in an embodiment, which is applied to a transformer winding online monitoring system, wherein the transformer winding online monitoring system includes a transformer and relay protection.

[0048] Optionally, we build Figure 2 The transformer winding online monitoring system shown in the figure is composed of a transformer 1, a signal generator 2, an input high-frequency sensor 3, an output high-frequency sensor 4, an input bushing 5, an output bushing 6, a current sensor 7, a temperature sensor 8, a signal acquisition device 9, a terminal device 10, a relay protection and a noise removal device. When the system is working, the signal generator 2 generates a sinusoidal sweep frequency excitation voltage signal Ui n(f), which is injected into the transformer 1 from the input bushing 5 through the input high-frequency sensor 3 after passing through the relay protection. The noise removal device collects the response end voltage signal Uout(f) at the root of the high-voltage bushing 6 from the output high-frequency sensor 4, and transmits the signal to the signal acquisition device 9 after filtering and noise removal. The current sensor 7 collects the transformer harmonic current I and differential current I d and relay protection current setting value I dz , the temperature sensor 8 collects the coil temperature T c 、Ambient temperature T e The signal is transmitted to the signal acquisition device 9 and processed and analyzed by the terminal device 10.

[0049] The steps provided by the transformer winding fault diagnosis and relay protection interference assessment method in this embodiment include:

[0050] S101, obtaining an amplitude-frequency response curve and a phase-frequency response curve of a transformer within a preset frequency band.

[0051] The preset frequency band can be set to 1kHz-1MHz, and the amplitude-frequency response curve represents the amplitude response of the transformer at different frequencies, which is expressed as:

[0052]

[0053] The phase-frequency response curve represents the phase response of the transformer at different frequencies, which is expressed as:

[0054]

[0055] S102, evenly divide the preset frequency band into multiple regional frequency bands, and respectively calculate the Euclidean distance of the amplitude-frequency response curve in each regional frequency band to obtain multiple amplitude-frequency regional Euclidean distances, and calculate the Euclidean distance of the phase-frequency response curve in each regional frequency band to obtain multiple phase-frequency regional Euclidean distances.

[0056] Here, by subdividing the frequency band into multiple regions, the change of frequency response can be analyzed more finely. For example, 1kHz-1MHz is evenly divided into 10 regional frequency bands.

[0057] In this step, the Euclidean distance is used to calculate the difference between two amplitude-frequency response curves (within a specific frequency band). Optionally, in S102, the Euclidean distance of the amplitude-frequency response curve in each regional frequency band is calculated to obtain multiple amplitude-frequency regional Euclidean distances, and the Euclidean distance of the phase-frequency response curve in each regional frequency band is calculated to obtain multiple phase-frequency regional Euclidean distances, which are expressed as:

[0058]

[0059] In the above formula, X M is the Euclidean distance of the amplitude-frequency region in any regional frequency band; V1 is the amplitude sequence of the fingerprint amplitude-frequency response curve in any regional frequency band, that is, the amplitude sequence in a certain regional frequency band in the amplitude-frequency response curve of the transformer in a healthy state; V2 is the amplitude sequence of the amplitude-frequency response curve after the fault in the same regional frequency band of V1; X P is the phase-frequency regional Euclidean distance of any regional frequency band; P1 is the phase sequence of the fingerprint phase-frequency response curve in any regional frequency band, that is, the phase sequence in a certain regional frequency band in the phase-frequency response curve of the transformer in a healthy state; P2 is the phase sequence of the phase-frequency response curve after fault in the same regional frequency band of P1.

[0060] As a quantitative indicator, Euclidean distance can reduce misjudgments and missed judgments in traditional diagnostic methods through accurate comparison of the above-mentioned health curve and fault curve.

[0061] S103, calculating a ratio of fused Euclidean distances according to a plurality of amplitude-frequency region Euclidean distances and a plurality of phase-frequency region Euclidean distances, and if the ratio of fused Euclidean distances falls within a preset distance interval, determining that a transformer winding is faulty.

[0062] The fused Euclidean distance ratio provides a more comprehensive metric to assess the overall health of the transformer winding by integrating the differences in amplitude and phase frequencies.

[0063] Optionally, in S103, the ratio of the fused Euclidean distance is calculated according to the Euclidean distances in the multiple amplitude-frequency regions and the Euclidean distances in the multiple phase-frequency regions, and is expressed as:

[0064]

[0065] In the above formula, X MMRI is the ratio of the fused Euclidean distance; X Mmax is the maximum value of the Euclidean distance of multiple amplitude-frequency regions; X Mmin is the minimum value of the Euclidean distance of multiple amplitude-frequency regions; XPmax is the maximum value of the Euclidean distance of multiple phase frequency regions; X Pmin It is the minimum value of the Euclidean distance of multiple phase frequency regions.

[0066] Furthermore, if the ratio of the fused Euclidean distance falls within a preset distance interval, it is determined that the transformer winding is faulty. Since the ratio of the fused Euclidean distance can comprehensively reflect the overall state of the transformer winding, it is more accurate than using amplitude frequency or phase frequency alone.

[0067] Optionally, if the ratio of the fused Euclidean distances falls within a preset distance interval in S103, it is determined that the transformer winding has a fault, including:

[0068] A1. If the ratio of the fused Euclidean distance falls within the preset first distance interval, it is determined that the transformer winding has an axial displacement fault; for example, the first distance interval is 200≤X MMRI ≤250.

[0069] The axial displacement fault refers to the displacement of the transformer winding position due to the axial force (along the main axis of the transformer).

[0070] A2. If the ratio of the fused Euclidean distance falls within the preset second distance interval, it is determined that the transformer winding has a radial deformation fault or a mixed fault. For example, the second distance interval is 0≤X MMRI ≤50.

[0071] In this way, by setting different distance intervals, different types of faults (such as axial displacement, radial deformation or mixed faults) can be accurately determined, thereby improving the accuracy of diagnosis.

[0072] Optionally, on the premise of determining that the transformer winding has a radial deformation fault or a mixed fault, the following steps may also be performed:

[0073] B1. Calculate the offset area ratio of the amplitude-frequency response curve, expressed as:

[0074]

[0075] In the above formula, S OA is the proportion of the offset area; V1(i) is the amplitude of the i-th point of the fingerprint amplitude-frequency response curve; V2(i) is the amplitude of the i-th point of the amplitude-frequency response curve after the fault; f(i) is the frequency corresponding to the i-th point;

[0076] The offset area ratio is used to describe the degree of change in the amplitude-frequency response curve before and after the transformer winding fault. This indicator can reflect the significance of the change in the amplitude-frequency response caused by the fault and is suitable for distinguishing radial deformation faults from mixed faults. Under radial deformation faults, the change in amplitude-frequency response is usually small, while in mixed faults, the change in amplitude-frequency response is large.

[0077] B2. If the offset area ratio is less than or equal to a preset ratio threshold, it is determined that the transformer winding has a radial deformation fault.

[0078] Among them, radial deformation fault refers to the change of winding shape due to compression or expansion of transformer winding, which affects its electrical characteristics, which is manifested as a small change in the amplitude-frequency response curve.

[0079] Optionally, the percentage threshold is set to 0.3.

[0080] B3. If the offset area ratio is greater than a preset ratio threshold, it is determined that a mixed fault exists in the transformer winding.

[0081] A mixed fault refers to multiple fault modes occurring simultaneously in the transformer winding, such as axial displacement and radial deformation, etc. Mixed faults will cause more complex frequency response changes, so the offset area accounts for a larger proportion.

[0082] By calculating the offset area ratio in this embodiment, radial deformation faults and mixed faults can be accurately distinguished, avoiding fuzzy judgments on complex fault modes in traditional methods.

[0083] S104, under the premise that there is a fault in the transformer winding, the online operation data of the transformer is obtained, and the impact evaluation factor of the relay protection is calculated based on the online operation data of the transformer. If the impact evaluation factor is less than the preset impact threshold, it is determined that the judgment result of the transformer winding fault is accurate.

[0084] Among them, online operation data refers to various types of electrical data that are monitored and recorded in real time during the normal operation of the transformer. The impact evaluation factor of relay protection is used to measure the degree of influence of the relay protection device on the transformer fault diagnosis results. The relay protection device will automatically cut off the circuit when a fault occurs, which may affect the measurement of the frequency response, so it is necessary to evaluate its impact on the accuracy of fault diagnosis. If the impact evaluation factor is less than the preset impact threshold, it can be considered that the relay protection has no significant interference with the fault diagnosis and the diagnosis result is accurate. Otherwise, the diagnosis result is inaccurate.

[0085] Optionally, in S104, the impact evaluation factor of relay protection is calculated based on the online operation data of the transformer, and is expressed as:

[0086]

[0087] In the above formula, I d is the differential current, which indicates the current difference of the transformer winding or system; I dz is the relay protection current setting value, indicating the current threshold that triggers the relay protection; T e is the ambient temperature; T c is the coil temperature; is the phase angle difference between voltage and current; θ is the internal angle of the power direction relay. (I d -I dz ) 3 This part represents the difference between the differential current and the relay protection current setting value, and its influence is magnified after cubic calculation. This is because the larger the current difference, the more serious the fault may be, which in turn affects the judgment of the relay protection. e -0.8714T c |This section takes into account the difference between the ambient temperature and the coil temperature. The greater the temperature difference, the more likely it is that the transformer is unstable, affecting the judgment of the relay protection. This section shows the impact of voltage, current and their phase difference on power factor. Voltage, current and their phase angle difference will affect the accuracy of fault detection and relay protection action.

[0088] Optionally, the impact threshold is set to 0.1. If the impact evaluation factor is less than the impact threshold 0.1, the judgment result that the transformer winding is faulty is accurate.

[0089] The above transformer winding fault diagnosis and relay protection interference assessment method obtains the amplitude-frequency response curve and phase-frequency response curve of the transformer in a preset frequency band, and calculates the Euclidean distance in each regional frequency band respectively, thereby obtaining the Euclidean distances of multiple amplitude-frequency regions and phase-frequency regions. Then, based on these Euclidean distance calculations, the ratio of the Euclidean distances is integrated to determine whether the transformer winding is faulty. At the same time, under the premise of a transformer winding fault, the influence evaluation factor of the relay protection is calculated in combination with the online operation data. If the factor is less than the preset threshold, it can be confirmed that the fault judgment result is accurate. This method particularly solves the problem that the prior art does not fully consider the interference that relay protection may cause to the transformer winding fault monitoring results, thereby ensuring the accuracy of fault judgment and avoiding the influence of relay protection misoperation or hysteresis on the monitoring results.

[0090] In one embodiment, Figure 3 As shown, a transformer winding fault diagnosis and relay protection interference assessment device is proposed, the device comprising:

[0091] An acquisition module 301 is used to acquire an amplitude-frequency response curve and a phase-frequency response curve of a transformer within a preset frequency band;

[0092] The Euclidean distance calculation module 302 is used to evenly divide the preset frequency band into a plurality of regional frequency bands, and respectively calculate the Euclidean distance of the amplitude-frequency response curve in each regional frequency band to obtain a plurality of amplitude-frequency regional Euclidean distances, and calculate the Euclidean distance of the phase-frequency response curve in each regional frequency band to obtain a plurality of phase-frequency regional Euclidean distances;

[0093] A fault diagnosis module 303 is used to calculate a ratio of fused Euclidean distances according to multiple Euclidean distances in amplitude-frequency regions and multiple Euclidean distances in phase-frequency regions, and if the ratio of fused Euclidean distances falls within a preset distance interval, it is determined that a transformer winding has a fault;

[0094] The impact assessment module 304 is used to obtain the online operation data of the transformer under the premise that there is a fault in the transformer winding, and calculate the impact assessment factor of the relay protection based on the online operation data of the transformer. If the impact assessment factor is less than the preset impact threshold, the judgment result that the transformer winding fault exists is accurate.

[0095] Figure 4 FIG. 2 shows an internal structure diagram of a terminal device in an embodiment. Figure 4 As shown, the terminal device includes a processor, a memory and a network interface connected via a system bus. Among them, the memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the terminal 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 a transformer winding fault diagnosis and relay protection interference assessment method. The internal memory may also store a computer program. When the computer program is executed by the processor, the processor can execute a transformer winding fault diagnosis and relay protection interference assessment method. Those skilled in the art can understand that Figure 4 The structure shown in the figure is only a block diagram of a partial structure related to the scheme of the present application, and does not constitute a limitation on the terminal device to which the scheme of the present application is applied. The specific terminal device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0096] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented: obtaining an amplitude-frequency response curve and a phase-frequency response curve of a transformer within a preset frequency band; evenly dividing the preset frequency band into a plurality of regional frequency bands, and respectively calculating the Euclidean distance of the amplitude-frequency response curve within each regional frequency band to obtain a plurality of amplitude-frequency regional Euclidean distances, and calculating the Euclidean distance of the phase-frequency response curve within each regional frequency band to obtain a plurality of phase-frequency regional Euclidean distances; calculating a ratio of fused Euclidean distances according to a plurality of amplitude-frequency regional Euclidean distances and a plurality of phase-frequency regional Euclidean distances, and if the ratio of the fused Euclidean distances falls within a preset distance interval, it is determined that a transformer winding has a fault; on the premise that a transformer winding has a fault, obtaining online operation data of the transformer, and calculating an impact evaluation factor of relay protection based on the online operation data of the transformer, and if the impact evaluation factor is less than a preset impact threshold, it is determined that the result of determining that a transformer winding has a fault is accurate.

[0097] A terminal device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program: obtaining an amplitude-frequency response curve and a phase-frequency response curve of a transformer within a preset frequency band; evenly dividing the preset frequency band into a plurality of regional frequency bands, and respectively calculating the Euclidean distance of the amplitude-frequency response curve within each regional frequency band to obtain a plurality of amplitude-frequency regional Euclidean distances, and calculating the Euclidean distance of the phase-frequency response curve within each regional frequency band to obtain a plurality of phase-frequency regional Euclidean distances; calculating a ratio of fused Euclidean distances according to a plurality of amplitude-frequency regional Euclidean distances and a plurality of phase-frequency regional Euclidean distances, and if the ratio of the fused Euclidean distances falls within a preset distance interval, it is determined that a transformer winding has a fault; on the premise that a transformer winding has a fault, obtaining online operation data of the transformer, and calculating an impact evaluation factor of relay protection based on the online operation data of the transformer, and if the impact evaluation factor is less than a preset impact threshold, it is determined that the result of determining that a transformer winding has a fault is accurate.

[0098] It should be noted that the above-mentioned transformer winding fault diagnosis and relay protection interference assessment method, device, equipment and computer-readable storage medium belong to a general inventive concept, and the contents in the transformer winding fault diagnosis and relay protection interference assessment method, device, equipment and computer-readable storage medium embodiments are applicable to each other.

[0099] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing related hardware through a computer program, and 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 may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct RAMbus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0100] The technical features of the above embodiments may 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.

[0101] 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.

Claims

1. A method for transformer winding fault diagnosis and relay protection interference assessment, characterized in that: Applied to a transformer winding online monitoring system, the transformer winding online monitoring system includes a transformer and relay protection, and the method includes: Obtaining the amplitude-frequency response curve and phase-frequency response curve of the transformer within a preset frequency band; The preset frequency band is evenly divided into a plurality of regional frequency bands, and the Euclidean distance of the amplitude-frequency response curve in each regional frequency band is calculated respectively to obtain a plurality of amplitude-frequency regional Euclidean distances, and the Euclidean distance of the phase-frequency response curve in each regional frequency band is calculated to obtain a plurality of phase-frequency regional Euclidean distances; Calculating a ratio of fused Euclidean distances according to the multiple Euclidean distances in amplitude-frequency regions and the multiple Euclidean distances in phase-frequency regions, and determining that a transformer winding is faulty if the ratio of the fused Euclidean distances falls within a preset distance interval; Under the premise that there is a fault in the transformer winding, the online operation data of the transformer is obtained, and the impact evaluation factor of the relay protection is calculated based on the online operation data of the transformer. If the impact evaluation factor is less than the preset impact threshold, the judgment result that there is a fault in the transformer winding is accurate.

2. The method according to claim 1, characterized in that The Euclidean distance of the amplitude-frequency response curve in each frequency band is calculated to obtain multiple amplitude-frequency regional Euclidean distances, and the Euclidean distance of the phase-frequency response curve in each frequency band is calculated to obtain multiple phase-frequency regional Euclidean distances, which are expressed as: In the above formula, X M is the Euclidean distance of the amplitude-frequency region in any regional frequency band; V1 is the amplitude sequence of the fingerprint amplitude-frequency response curve in any regional frequency band; V2 is the amplitude sequence of the amplitude-frequency response curve after the fault in the same regional frequency band of V1; X P is the phase-frequency regional Euclidean distance of any regional frequency band; P1 is the phase sequence of the fingerprint phase-frequency response curve in any regional frequency band; P2 is the phase sequence of the phase-frequency response curve after the fault in the same regional frequency band of P1.

3. The method according to claim 1, characterized in that The ratio of the fused Euclidean distance calculated according to the Euclidean distances in the multiple amplitude-frequency regions and the Euclidean distances in the multiple phase-frequency regions is expressed as: In the above formula, X MMRI is the ratio of the fused Euclidean distance; X Mmax is the maximum value of the Euclidean distances of the multiple amplitude-frequency regions; Mmin is the minimum value of the Euclidean distances of the multiple amplitude-frequency regions; Pmax is the maximum value of the Euclidean distances of the multiple phase frequency regions; Pmin is the minimum value of the Euclidean distances of the multiple phase-frequency regions.

4. The method according to claim 1, characterized in that: If the ratio of the fused Euclidean distances falls within a preset distance interval, it is determined that a transformer winding has a fault, including: If the ratio of the fused Euclidean distances falls within a preset first distance interval, it is determined that an axial displacement fault exists in the transformer winding; If the ratio of the fused Euclidean distances falls within a preset second distance interval, it is determined that a radial deformation fault or a mixed fault exists in the transformer winding.

5. The method according to claim 4, characterized in that On the premise of determining that the transformer winding has a radial deformation fault or a mixed fault, the method further includes: Calculate the offset area ratio of the amplitude-frequency response curve, expressed as: In the above formula, S OA is the proportion of the offset area; V1(i) is the amplitude of the i-th point of the fingerprint amplitude-frequency response curve; V2(i) is the amplitude of the i-th point of the amplitude-frequency response curve after the fault; f(i) is the frequency corresponding to the i-th point; If the offset area ratio is less than or equal to the preset ratio threshold, it is determined that the transformer winding has a radial deformation fault; if the offset area ratio is greater than the preset ratio threshold, it is determined that the transformer winding has a mixed fault.

6. The method according to claim 1, characterized in that The influence evaluation factor of relay protection calculated based on the online operation data of the transformer is expressed as: In the above formula, I d is the differential current; I dz is the setting value of relay protection current; T e is the ambient temperature; T c is the ambient temperature; is the phase angle difference between voltage and current; θ is the internal angle of the power directional relay.

7. A transformer winding fault diagnosis and relay protection interference assessment device, characterized in that: Applied to a transformer winding online monitoring system, the transformer winding online monitoring system includes a transformer and relay protection, and the transformer winding fault diagnosis and relay protection interference assessment device includes: An acquisition module, used to acquire an amplitude-frequency response curve and a phase-frequency response curve of the transformer within a preset frequency band; A Euclidean distance calculation module, used for evenly dividing the preset frequency band into a plurality of regional frequency bands, and respectively calculating the Euclidean distance of the amplitude-frequency response curve in each regional frequency band to obtain a plurality of amplitude-frequency regional Euclidean distances, and calculating the Euclidean distance of the phase-frequency response curve in each regional frequency band to obtain a plurality of phase-frequency regional Euclidean distances; A fault diagnosis module, used for calculating a ratio of fused Euclidean distances according to the multiple Euclidean distances in amplitude-frequency regions and the multiple Euclidean distances in phase-frequency regions, and determining that a transformer winding has a fault if the ratio of the fused Euclidean distances falls within a preset distance interval; The impact assessment module is used to obtain the online operation data of the transformer under the premise that there is a fault in the transformer winding, and calculate the impact assessment factor of the relay protection based on the online operation data of the transformer. If the impact assessment factor is less than a preset impact threshold, the judgment result that there is a fault in the transformer winding is accurate.

8. The transformer winding fault diagnosis and relay protection interference assessment device according to claim 7, characterized in that: Euclidean distance calculation module, specifically used to calculate: In the above formula, X M is the Euclidean distance of the amplitude-frequency region in any regional frequency band; V1 is the amplitude sequence of the fingerprint amplitude-frequency response curve in any regional frequency band; V2 is the amplitude sequence of the amplitude-frequency response curve after the fault in the same regional frequency band of V1; X P is the phase-frequency regional Euclidean distance of any regional frequency band; P1 is the phase sequence of the fingerprint phase-frequency response curve in any regional frequency band; P2 is the phase sequence of the phase-frequency response curve after the fault in the same regional frequency band of P1.

9. A computer-readable storage medium, characterized in that: A computer program is stored, and when the computer program is executed by a processor, the processor is caused to execute the steps of the method according to any one of claims 1 to 6.

10. A terminal 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 6.

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