A method, device and system for detecting winding deformation faults in a three-phase transformer.

Abstract

This invention discloses a method, device, and system for detecting deformation faults in three-phase transformer windings, belonging to the field of transformer fault detection. Since the parameters used are capacitance, oscillation frequency, and oscillation amplitude, their changes in ratio can reflect whether the distance or the area directly opposite has changed. Therefore, by using two sets of capacitances to ground and between phases, respectively, the transformer can be judged whether it has experienced deformation faults to ground and between phases. Furthermore, the parameters to ground are for each phase, while those between phases are for two phases, allowing for accurate identification of which phase of the transformer is experiencing the fault. This application's solution compares the current parameters at the current time with preset standard parameters, enabling rapid determination of whether a transformer has experienced a deformation fault, and accurately identifying which phase is faulty when a fault occurs. It has the advantages of high sensitivity, good accuracy, and accurate location.

Description

Technical Field

[0001] This invention relates to the field of transformer fault detection, and in particular, to a method, apparatus, and system for detecting winding deformation faults in a three-phase transformer. Background Technology

[0002] When a transformer is subjected to a sudden short-circuit impact during operation, the windings may loosen. This mechanical failure can further reduce the transformer's short-circuit withstand capability, leading to a more serious accident. Therefore, determining whether the windings have deformed and locating the fault is an important method for preventing serious accidents involving large transformers.

[0003] Existing methods for judging loose windings include short-circuit impedance method and frequency response method, but they all have problems such as low sensitivity, difficulty in detecting small deformations of the winding, and inability to accurately locate faults. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention provides a method, device and system for detecting three-phase transformer winding deformation faults, so as to solve the problem that the existing winding loosening judgment method has low sensitivity, is difficult to detect small deformations of the winding, and cannot accurately locate the fault.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] Firstly, a method for detecting winding deformation faults in a three-phase transformer is provided, comprising the following steps:

[0007] The current parameters of each phase of the transformer at the current moment are obtained. These current parameters include the current capacitance to ground, the current phase-to-phase capacitance, the current frequency of the ground oscillation wave, the current frequency of the phase-to-phase oscillation wave, the current amplitude of the ground oscillation wave, and the current amplitude of the phase-to-phase oscillation wave. The current capacitance to ground is the capacitance to ground of each phase winding of the transformer; the current phase-to-phase capacitance is the phase-to-phase capacitance between each phase winding of the transformer; the current frequency of the ground oscillation wave is the oscillation frequency of the resonant circuit of each phase winding of the transformer to ground; the current frequency of the phase-to-phase oscillation wave is the oscillation frequency of the resonant circuit between each phase winding of the transformer; the current amplitude of the ground oscillation wave is the amplitude of the resonant circuit of each phase winding of the transformer to ground; and the current amplitude of the phase-to-phase oscillation wave is the amplitude of the resonant circuit between each phase winding of the transformer.

[0008] The difference between any current parameter and the corresponding preset standard parameter is then compared with the standard parameter to obtain a ratio. The ratio includes the ratio of the change in capacitance to ground, the ratio of the change in capacitance between phases, the ratio of the change in the frequency of the ground oscillation wave, the change in the frequency of the phase oscillation wave, the ratio of the change in the amplitude of the ground oscillation wave, and the ratio of the change in the amplitude of the phase oscillation wave.

[0009] If the absolute values ​​of the ground capacitance change ratio, ground oscillation wave frequency change ratio, and ground oscillation wave amplitude change ratio of any phase are all greater than a first preset value, then the winding of that phase is determined to have a ground deformation fault; if the absolute values ​​of the ground capacitance change ratio, ground oscillation wave frequency change ratio, and ground oscillation wave amplitude change ratio of any phase are all less than the first preset value, then the winding of the transformer is determined not to have a ground deformation fault; and / or, if the absolute values ​​of the phase-to-phase capacitance change ratio, phase-to-phase oscillation wave frequency change ratio, and phase-to-phase oscillation wave amplitude change ratio between any phase and at least one of the other two phases are all greater than a second preset value, then the winding of that phase is determined to have a phase-to-phase deformation fault; if the absolute values ​​of the phase-to-phase capacitance change ratio, phase-to-phase oscillation wave frequency change ratio, and phase-to-phase oscillation wave amplitude change ratio between any phase and the other two phases are all less than the second preset value, then the winding of that phase is determined not to have a phase-to-phase deformation fault.

[0010] Furthermore, it also includes: when it is determined that the winding of the phase has a deformation fault to ground, if the ratio of the change in capacitance to ground of the faulty phase is greater than 0, the ratio of the change in frequency of the ground oscillation wave is less than 0, and the ratio of the change in amplitude of the ground oscillation wave is less than 0, then it is determined that the winding of the faulty phase has undergone radial extension or tilting.

[0011] Furthermore, it also includes: when it is determined that the winding of the phase has a deformation fault to ground, if the ratio of the change in capacitance to ground of the faulty phase is less than 0, the ratio of the change in frequency of the ground oscillation wave is greater than 0, and the ratio of the change in amplitude of the ground oscillation wave is greater than 0, then it is determined that the winding of the faulty phase has undergone radial compression.

[0012] Furthermore, it also includes: the three phases of the three-phase transformer are phase A, phase B and phase C, wherein the core of phase B is located between the core of phase A and the core of phase C;

[0013] When it is determined that a phase-to-phase deformation fault has occurred in the winding of phase A or phase C, if the ratio of the phase-to-phase capacitance change of the faulty phase to the other two phases is greater than 0, and the ratio of the phase-to-phase oscillation wave frequency change and the phase-to-phase oscillation wave amplitude change of the faulty phase to the other two phases is less than 0, then it is determined that the faulty phase has undergone axial compression or outward tilting.

[0014] Furthermore, it also includes: the three phases of the three-phase transformer are phase A, phase B and phase C, wherein the core of phase B is located between the core of phase A and the core of phase C;

[0015] When it is determined that a phase-to-phase deformation fault has occurred in the winding of phase A or phase C, if the ratio of the phase-to-phase capacitance change of the faulty phase to the other two phases is less than 0, and the ratio of the phase-to-phase oscillation wave frequency change and the phase-to-phase oscillation wave amplitude change of the faulty phase to the other two phases is greater than 0, then it is determined that the faulty phase has undergone axial extension or inward tilting.

[0016] Furthermore, it also includes: the three phases of the three-phase transformer are phase A, phase B, and phase C, wherein the core of phase B is located between the cores of phase A and phase C; when it is determined that an interphase deformation fault has occurred in the winding of phase B,

[0017] If the ratio of the phase-to-phase capacitance change between phase B and phase A is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all less than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase C, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial extension on the phase A side.

[0018] If the ratio of the phase-to-phase capacitance change between phase B and phase A is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all greater than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase C, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial compression on the phase A side.

[0019] If the ratio of the phase-to-phase capacitance change between phase B and phase C is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all less than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase A, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial extension on the phase C side.

[0020] If the ratio of the phase-to-phase capacitance change between phase B and phase C is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all greater than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase A, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial compression on the phase C side.

[0021] Furthermore, it also includes: the three phases of the three-phase transformer are phase A, phase B, and phase C, wherein the core of phase B is located between the cores of phase A and phase C; when it is determined that an interphase deformation fault has occurred in the winding of phase B,

[0022] If the ratio of the phase-to-phase capacitance change between phase B and phase A is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are both less than 0, and the ratio of the phase-to-phase capacitance change between phase B and phase C is less than 0, and the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are both greater than 0, then it is determined that the phase B winding has tilted towards the phase A side.

[0023] If the ratio of the phase-to-phase capacitance change between phase B and phase A is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are both greater than 0, and the ratio of the phase-to-phase capacitance change between phase B and phase C is greater than 0, and the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are both less than 0, then it is determined that the phase B winding has tilted towards the phase A side.

[0024] Furthermore, it also includes:

[0025] When the product of the ratio of the change in capacitance to ground of any phase with the ratio of the change in frequency of its ground oscillation wave or the ratio of the change in amplitude of its ground oscillation wave is greater than 0, the data of that phase is judged to be abnormal.

[0026] When the product of the ratio of the frequency change of the ground oscillation wave of any phase to the ratio of the amplitude change of the ground oscillation wave is less than 0, the data of that phase is judged to be abnormal.

[0027] When the product of the ratio of the phase capacitance change between any two phases and the ratio of the phase oscillation frequency change or the ratio of the phase oscillation amplitude change between the two phases is greater than 0, the data between the two phases is judged to be abnormal.

[0028] When the product of the ratio of the frequency change of the interphase oscillation wave between any two phases and the ratio of the amplitude change of the interphase oscillation wave between the two phases is less than 0, the data between the two phases is judged to be abnormal.

[0029] Secondly, a three-phase transformer winding deformation fault detection device is provided, comprising:

[0030] The parameter acquisition module is used to acquire the current parameters of each phase of the transformer at the current moment. The current parameters include the current ground capacitance, current phase-to-phase capacitance, current ground oscillation frequency, current phase-to-phase oscillation frequency, current ground oscillation amplitude, and current phase-to-phase oscillation amplitude. The current ground capacitance is the ground capacitance of each phase winding of the transformer; the current phase-to-phase capacitance is the phase-to-phase capacitance between each phase winding of the transformer; the current ground oscillation frequency is the oscillation frequency of the resonant circuit of each phase winding of the transformer to ground; the current phase-to-phase oscillation frequency is the oscillation frequency of the resonant circuit between each phase winding of the transformer; the current ground oscillation amplitude is the oscillation amplitude of the resonant circuit of each phase winding of the transformer to ground; and the current phase-to-phase oscillation amplitude is the oscillation amplitude of the resonant circuit between each phase winding of the transformer.

[0031] The ratio acquisition module is used to calculate the difference between any current parameter and the corresponding preset standard parameter, and then compare the difference with the standard parameter to obtain a ratio. The ratio includes the ground capacitance change ratio, the phase-to-phase capacitance change ratio, the ground oscillation wave frequency change ratio, the phase-to-phase oscillation wave frequency change value, the ground oscillation wave amplitude change ratio, and the phase-to-phase oscillation wave amplitude change ratio.

[0032] The fault judgment module is configured to determine that the winding of any phase has a ground deformation fault if the absolute values ​​of the ground capacitance change ratio, the ground oscillation wave frequency change ratio, and the ground oscillation wave amplitude change ratio of any phase are all greater than a first preset value; and to determine that the winding of the transformer has not experienced a ground deformation fault if the absolute values ​​of the ground capacitance change ratio, the ground oscillation wave frequency change ratio, and the ground oscillation wave amplitude change ratio of any phase are all less than the first preset value; and / or, to determine that the winding of any phase has an interphase deformation fault if the absolute values ​​of the interphase capacitance change ratio, the interphase oscillation wave frequency change ratio, and the interphase oscillation wave amplitude change ratio of any phase and at least one of the other two phases are all greater than a second preset value; and to determine that the winding of any phase has not experienced an interphase deformation fault if the absolute values ​​of the interphase capacitance change ratio, the interphase oscillation wave frequency change ratio, and the interphase oscillation wave amplitude change ratio of any phase and the other two phases are all less than the second preset value.

[0033] Thirdly, a three-phase transformer winding deformation fault detection system is provided, including:

[0034] processor;

[0035] Memory used to store the processor's executable instructions;

[0036] The processor is configured to perform the method described in any one of the technical solutions provided in the first aspect.

[0037] Beneficial effects:

[0038] This application discloses a method, device, and system for detecting deformation faults in three-phase transformer windings. First, the current parameters of each phase of the transformer are acquired. Then, the current parameters are compared with preset standard parameters to obtain the ratio of changes. Finally, the transformer winding deformation fault is determined based on the ratio of changes. Since the parameters used are capacitance, oscillation frequency, and oscillation amplitude, their ratios reflect changes in distance or opposing area. Therefore, by using two sets of capacitances (to ground and between phases), oscillation frequency, and oscillation amplitude, it is possible to determine whether the transformer has experienced deformation faults to ground and between phases. Furthermore, the parameters to ground are for each phase, while those between phases are for two phases, allowing for accurate identification of which phase of the transformer is experiencing the fault. This application's solution, by comparing the current parameters with preset standard parameters, can quickly determine whether a transformer has experienced a deformation fault, and accurately identify which phase is faulty when a fault occurs. It has the advantages of high sensitivity, good accuracy, and accurate location. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a flowchart of a method for detecting deformation faults in three-phase transformer windings provided by an embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram of a three-phase transformer winding deformation fault detection device provided in an embodiment of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of the present invention will be described in detail below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0043] The first embodiment, referred to Figure 1 This invention provides a method for detecting deformation faults in three-phase transformer windings, comprising the following steps:

[0044] S11: Obtain the current parameters of each phase of the transformer at the current moment. The current parameters include the current capacitance to ground, the current phase-to-phase capacitance, the current frequency of the ground oscillation wave, the current frequency of the phase-to-phase oscillation wave, the current amplitude of the ground oscillation wave, and the current amplitude of the phase-to-phase oscillation wave. The current capacitance to ground is the capacitance to ground of each phase winding of the transformer; the current phase-to-phase capacitance is the phase-to-phase capacitance between each phase winding of the transformer; the current frequency of the ground oscillation wave is the oscillation wave frequency of the resonant circuit of each phase winding of the transformer to ground; the current frequency of the phase-to-phase oscillation wave is the oscillation wave frequency of the resonant circuit between each phase winding of the transformer; the current amplitude of the ground oscillation wave is the amplitude of the resonant circuit of each phase winding of the transformer to ground; the current amplitude of the phase-to-phase oscillation wave is the amplitude of the resonant circuit between each phase winding of the transformer.

[0045] S12: Subtract any current parameter from the corresponding preset standard parameter, and then compare the difference with the standard parameter to obtain a ratio. The ratio includes the ratio of the change in capacitance to ground, the ratio of the change in capacitance between phases, the ratio of the change in the frequency of the ground oscillation wave, the change in the frequency of the phase oscillation wave, the ratio of the change in the amplitude of the ground oscillation wave, and the ratio of the change in the amplitude of the phase oscillation wave.

[0046] S13: If the absolute values ​​of the ratio of the change in capacitance to ground, the ratio of the change in frequency of the ground oscillation wave, and the ratio of the change in amplitude of the ground oscillation wave of any phase are all greater than the first preset value, then it is determined that the winding of the phase has a deformation fault to ground.

[0047] S14: If the absolute values ​​of the ratio of the change in capacitance to ground, the ratio of the change in frequency of the ground oscillation wave, and the ratio of the change in amplitude of the ground oscillation wave of any phase are all less than the first preset value, then it is determined that the transformer winding has not experienced a ground deformation fault; and / or,

[0048] S15: If the absolute values ​​of the ratio of the phase-to-phase capacitance change, the ratio of the phase-to-phase oscillation frequency change, and the ratio of the phase-to-phase oscillation amplitude change between any phase and at least one of the other two phases are all greater than the second preset value, then it is determined that the winding of the phase has a phase-to-phase deformation fault.

[0049] S16: If the absolute values ​​of the ratio of phase-to-phase capacitance change, the ratio of phase-to-phase oscillation frequency change, and the ratio of phase-to-phase oscillation amplitude change between any phase and the other two phases are all less than the second preset value, then it is determined that the phase winding has not experienced a phase-to-phase deformation fault.

[0050] The three-phase transformer winding deformation fault detection method provided in this invention first obtains the current parameters of each phase of the transformer at the current moment, then compares the current parameters with preset standard parameters to obtain the change ratio; finally, it determines whether the transformer winding has experienced a deformation fault based on the change ratio. Since the parameters used are capacitance, oscillation frequency, and oscillation amplitude, their change ratios can reflect whether the distance or the area directly opposite has changed; therefore, by using two sets of capacitances to ground and between phases, respectively, it is possible to determine whether the transformer has experienced deformation faults to ground and between phases. Furthermore, the parameters to ground are for each phase, while the parameters between phases are for two phases, allowing for accurate identification of which phase of the transformer is experiencing the fault. This application's solution, by comparing the current parameters at the current time with preset standard parameters, can quickly determine whether the transformer has experienced a deformation fault, and accurately identify which phase has the fault when it occurs, exhibiting advantages such as high sensitivity, good accuracy, and accurate positioning.

[0051] In a second embodiment, as a supplementary explanation to the first embodiment, the present invention provides a specific method for detecting deformation faults in three-phase transformer windings, comprising the following steps:

[0052] Obtain the current parameters of each phase of the transformer at the current moment. The current parameters include the current capacitance to ground, the current phase-to-phase capacitance, the current frequency of the ground oscillation wave, the current frequency of the phase-to-phase oscillation wave, the current amplitude of the ground oscillation wave, and the current amplitude of the phase-to-phase oscillation wave. The current capacitance to ground is the capacitance to ground of each phase winding of the transformer; the current phase-to-phase capacitance is the phase-to-phase capacitance between each phase winding of the transformer; the current frequency of the ground oscillation wave is the oscillation wave frequency of the resonant circuit of each phase winding of the transformer to ground; the current frequency of the phase-to-phase oscillation wave is the oscillation wave frequency of the resonant circuit between each phase winding of the transformer; the current amplitude of the ground oscillation wave is the amplitude of the resonant circuit of each phase winding of the transformer to ground; the current amplitude of the phase-to-phase oscillation wave is the amplitude of the resonant circuit between each phase winding of the transformer.

[0053] The ratio is obtained by subtracting any current parameter from its corresponding preset standard parameter and then comparing the difference with the standard parameter. The ratios include the ground capacitance change ratio, the phase-to-phase capacitance change ratio, the ground oscillation frequency change ratio, the phase-to-phase oscillation frequency change value, the ground oscillation amplitude change ratio, and the phase-to-phase oscillation amplitude change ratio. It should be noted that the preset standard parameters are the standard ground capacitance, standard phase-to-phase capacitance, standard ground oscillation frequency, standard phase-to-phase oscillation frequency, standard ground oscillation amplitude, and standard phase-to-phase oscillation amplitude measured when the transformer leaves the factory or is used for the first time. Taking the ground capacitance change ratio as an example, the calculation process for each ratio is explained as follows: Ground capacitance change ratio = (current ground capacitance - standard ground capacitance) / standard ground capacitance. The ratios for other parameters are similar and will not be explained in detail here.

[0054] If the absolute values ​​of the ratios of the capacitance to ground, the frequency of the ground oscillation wave, and the amplitude of the ground oscillation wave in any phase are all greater than a first preset value, then the winding of that phase is judged to have a ground deformation fault. It should be noted that the first preset value ranges from 10% to 20%, and in practical applications, a value within this range should be determined as the first preset value based on actual needs. The principle of judging ground deformation faults is as follows: First, the capacitance to ground refers to the capacitance between the winding of that phase of the transformer and the ground. Second, the capacitance determination formula is C = εs / 4πkd, where the letters represent the following: ε represents the dielectric between the two plates, such as air; the dielectric constant of metal plates is different. s represents the area of ​​the two plates facing each other; misalignment of the plates will reduce the area of ​​the plates facing each other, thus reducing the capacitance. d represents the distance between the two plates, and C represents the capacitance. If the capacitance to ground changes while other parameters remain constant, it can be judged that the distance or the area of ​​the plates facing each other has changed, i.e., the transformer winding has deformed. Therefore, when the ratio of the capacitance change to ground exceeds a first preset value, it can be determined that the winding has deformed. Furthermore, when other conditions of the winding relative to ground remain unchanged, the oscillation wave frequency and amplitude are inversely proportional to the capacitance; thus, the accuracy of the capacitance change can be further determined by the oscillation wave frequency and amplitude, and this dual determination makes the result more accurate. Moreover, based on the above principles, it can be determined that the ratio of the capacitance change to ground should be opposite in sign to the ratio of the oscillation wave frequency change to ground or the ratio of the oscillation wave amplitude change, while the ratio of the oscillation wave frequency change to ground and the ratio of the oscillation wave amplitude change should be the same in sign. These two conditions can also be used to determine whether the acquired ground data is correct.

[0055] If it is determined that a deformation fault to ground has occurred in a certain phase winding, the specific type of fault can be determined based on the magnitude of its ground capacitance change ratio, ground oscillation wave frequency change ratio, and ground oscillation wave amplitude change ratio.

[0056] Specifically, if the ratio of the change in capacitance to ground of the faulty phase is greater than 0, the ratio of the change in frequency of the ground oscillation wave is less than 0, and the ratio of the change in amplitude of the ground oscillation wave is less than 0, then it is determined that the winding of the faulty phase has experienced radial extension or tilting. A ratio of the change in capacitance to ground greater than 0 indicates that the current capacitance has increased, which means the distance between the windings has decreased or the area directly opposite the ground has increased. That is, radial extension or tilting has occurred. In a transformer, each phase winding is wound on an iron core, which is vertically elongated and, in practice, its long side is perpendicular to the ground. Therefore, a decrease in distance indicates radial extension, and an increase in the area directly opposite the ground indicates tilting.

[0057] If the ratio of the change in capacitance to ground of the faulty phase is less than 0, the ratio of the change in frequency of the ground oscillation wave is greater than 0, and the ratio of the change in amplitude of the ground oscillation wave is greater than 0, then it is determined that the winding of the faulty phase has undergone radial compression. A ratio of the change in capacitance to ground less than 0 indicates that the current capacitance has decreased, which means the distance has increased, i.e., radial compression has occurred.

[0058] If the absolute values ​​of the ratio of capacitance change to ground, the ratio of frequency change to ground oscillation wave, and the ratio of amplitude change to ground oscillation wave of any phase are all less than the first preset value, then it is determined that the transformer winding has not experienced a ground deformation fault.

[0059] If the absolute values ​​of the ratio of the phase-to-phase capacitance change, the ratio of the phase-to-phase oscillation frequency change, and the ratio of the phase-to-phase oscillation amplitude change between any phase and at least one of the other two phases are all greater than the second preset value, then it is determined that the phase winding has a phase-to-phase deformation fault. The first preset value is in the range of 10%-20%. In actual application, a value within this range is determined as the first preset value according to actual needs.

[0060] The principle for judging phase-to-phase deformation faults is the same as that for ground-to-phase deformation faults, except that the deformation between each phase winding and ground is replaced by the capacitance between each phase winding, as well as the amplitude and frequency of the oscillation wave. Further explanation is omitted here. Based on the judgment principle, it can be determined that the signs of the ratio of phase-to-phase capacitance changes should be opposite to those of the ratio of phase-to-phase oscillation wave frequency changes or the ratio of phase-to-phase oscillation wave amplitude changes, while the signs of the ratio of phase-to-phase oscillation wave frequency changes and the ratio of phase-to-phase oscillation wave amplitude changes should be the same. These two conditions can also be used to determine whether the acquired phase-to-phase data is correct.

[0061] When it is determined that a phase has an interphase fault, the specific type of fault in that phase is determined by the ratio of the interphase capacitance change to the other two phases, the ratio of the interphase oscillation frequency change, and the ratio of the interphase oscillation amplitude change.

[0062] A three-phase transformer has three phases: A, B, and C. The core of phase B is located between the cores of phases A and C. Because phase B is positioned differently from phases A and C, the types of faults that can be identified also differ. Taking phase A as an example, since phases B and C are both on the same side as phase A, the interphase capacitance changes of phases A and B should follow the same trend as those of phases A and C. Therefore, it is only necessary to determine whether the capacitance is axially compressed (outwardly tilted) or axially extended (inwardly tilted). The specifics are as follows:

[0063] When it is determined that a phase-to-phase deformation fault has occurred in the winding of phase A or phase C, if the ratio of the phase-to-phase capacitance change of the faulty phase to the other two phases is greater than 0, and the ratio of the phase-to-phase oscillation wave frequency change and the phase-to-phase oscillation wave amplitude change of the faulty phase to the other two phases is less than 0, then it is determined that the faulty phase has undergone axial compression or outward tilting.

[0064] When it is determined that a phase-to-phase deformation fault has occurred in the winding of phase A or phase C, if the ratio of the phase-to-phase capacitance change of the faulty phase to the other two phases is less than 0, and the ratio of the phase-to-phase oscillation wave frequency change and the phase-to-phase oscillation wave amplitude change of the faulty phase to the other two phases is greater than 0, then it is determined that the faulty phase has undergone axial extension or inward tilting.

[0065] When a phase-to-phase deformation fault is detected in the B-phase winding: Because the winding is wound on the iron core, if only one side of the B-phase winding (the side closest to phase A and the side closest to phase C) deforms, it will not affect the interphase capacitance, interphase oscillation frequency, or interphase oscillation amplitude on the other side. Therefore, a specific judgment needs to be made based on the parameters of both sides, as follows:

[0066] If the ratio of the phase-to-phase capacitance change between phase B and phase A is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all less than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase C, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial extension on the phase A side.

[0067] If the ratio of the phase-to-phase capacitance change between phase B and phase A is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all greater than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase C, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial compression on the side near phase A.

[0068] If the ratio of the phase-to-phase capacitance change between phase B and phase C is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all less than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase A, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial extension on the phase C side.

[0069] If the ratio of the phase-to-phase capacitance change between phase B and phase C is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all greater than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase A, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that axial compression has occurred on the phase C side of the phase B winding.

[0070] If the ratio of the phase-to-phase capacitance change between phase B and phase A is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A, and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all less than 0, and the ratio of the phase-to-phase capacitance change between phase B and phase C is less than 0, and the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C, and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all greater than 0, then it is determined that the phase B winding has tilted towards the phase A side. It should be noted that tilting is generally the tilting of the iron core, so its parameters with respect to phase A and phase C will change. Of course, this situation may also be that the phase B winding has axially extended on the phase A side and axially compressed on the phase C side, but this situation is less likely to occur in practice because the windings on the phase A side and the phase C side are the same winding. Therefore, in this application, it is only judged as tilting.

[0071] If the ratio of the phase-to-phase capacitance change between phase B and phase A is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are both greater than 0, and the ratio of the phase-to-phase capacitance change between phase B and phase C is greater than 0, and the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are both less than 0, then it is determined that the phase B winding has tilted towards the phase A side.

[0072] Understandably, based on the same principle, the ratio of the phase capacitance changes between phases AB and BC, the ratio of the phase oscillation frequency changes, and the ratio of the phase oscillation amplitude changes can also be used to determine whether the windings on both sides of phase B are simultaneously axially compressed or axially extended.

[0073] If the absolute values ​​of the ratio of the phase-to-phase capacitance change, the ratio of the phase-to-phase oscillation frequency change, and the ratio of the phase-to-phase oscillation amplitude change between any phase and the other two phases are all less than the second preset value, then it is determined that the phase winding has not experienced a phase-to-phase deformation fault.

[0074] The specific three-phase transformer winding deformation fault detection method provided in this invention first obtains the current parameters of each phase of the transformer at the current moment, then compares the current parameters with preset standard parameters to obtain the change ratio; finally, it determines whether the transformer winding has experienced a deformation fault based on the change ratio. Since the parameters used are capacitance, oscillation frequency, and oscillation amplitude, their change ratios can reflect whether the distance or the area directly opposite has changed; therefore, by using two sets of capacitances to ground and between phases, respectively, it is possible to determine whether the transformer has experienced deformation faults to ground and between phases. Furthermore, the parameters to ground are for each phase, while the parameters between phases are for two phases, allowing for accurate identification of which phase of the transformer is experiencing the fault. This application's solution, by comparing the current parameters at the current time with preset standard parameters, can quickly determine whether the transformer has experienced a deformation fault, and accurately identify which phase has experienced the fault when one occurs, exhibiting advantages such as high sensitivity, good accuracy, and accurate positioning.

[0075] In a third embodiment, the present invention provides a three-phase transformer winding deformation fault detection device, such as... Figure 2 As shown, it includes:

[0076] The parameter acquisition module 21 is used to acquire the current parameters of each phase of the transformer at the current moment. The current parameters include the current ground capacitance, the current phase-to-phase capacitance, the current ground oscillation frequency, the current phase-to-phase oscillation frequency, the current ground oscillation amplitude, and the current phase-to-phase oscillation amplitude. The current ground capacitance is the ground capacitance of each phase winding of the transformer; the current phase-to-phase capacitance is the phase-to-phase capacitance between each phase winding of the transformer; the current ground oscillation frequency is the oscillation frequency of the resonant circuit of each phase winding of the transformer to ground; the current phase-to-phase oscillation frequency is the oscillation frequency of the resonant circuit between each phase winding of the transformer; the current ground oscillation amplitude is the oscillation amplitude of the resonant circuit of each phase winding of the transformer to ground; and the current phase-to-phase oscillation amplitude is the oscillation amplitude of the resonant circuit between each phase winding of the transformer.

[0077] The ratio acquisition module 22 is used to obtain a ratio by subtracting any current parameter from the corresponding preset standard parameter and then comparing the difference with the standard parameter. The ratio includes the ratio of the change in capacitance to ground, the ratio of the change in capacitance between phases, the ratio of the change in frequency of the ground oscillation wave, the change in frequency of the phase oscillation wave, the ratio of the change in amplitude of the ground oscillation wave, and the ratio of the change in amplitude of the phase oscillation wave.

[0078] In addition, the ratio acquisition module 22 is also used to determine that the phase data is abnormal when the product of the ratio of the change in the capacitance to ground of any phase with the ratio of the change in the frequency of the ground oscillation wave or the ratio of the change in the amplitude of the ground oscillation wave is greater than 0; when the product of the ratio of the change in the frequency of the ground oscillation wave of any phase with the ratio of the change in the amplitude of the ground oscillation wave is less than 0; when the product of the ratio of the change in the interphase capacitance between any two phases with the ratio of the change in the frequency of the interphase oscillation wave between the two phases or the ratio of the change in the amplitude of the interphase oscillation wave between the two phases is greater than 0; and when the product of the ratio of the change in the frequency of the interphase oscillation wave between any two phases with the ratio of the change in the amplitude of the interphase oscillation wave between the two phases is less than 0.

[0079] The fault judgment module 23 is used to determine that the winding of any phase has a ground deformation fault if the absolute values ​​of the ground capacitance change ratio, the ground oscillation wave frequency change ratio, and the ground oscillation wave amplitude change ratio of any phase are all greater than a first preset value; and to determine that the winding of the transformer has not experienced a ground deformation fault if the absolute values ​​of the ground capacitance change ratio, the ground oscillation wave frequency change ratio, and the ground oscillation wave amplitude change ratio of any phase are all less than the first preset value; and / or, to determine that the winding of any phase has an interphase deformation fault if the absolute values ​​of the interphase capacitance change ratio, the interphase oscillation wave frequency change ratio, and the interphase oscillation wave amplitude change ratio of any phase and at least one of the other two phases are all greater than a second preset value; and to determine that the winding of any phase has not experienced an interphase deformation fault if the absolute values ​​of the interphase capacitance change ratio, the interphase oscillation wave frequency change ratio, and the interphase oscillation wave amplitude change ratio of any phase and the other two phases are all less than the second preset value.

[0080] The fault judgment module 23 is also used to determine that the winding of the faulty phase has undergone radial extension or tilting when the phase winding is judged to have a ground deformation fault. If the ratio of the change in capacitance to ground of the faulty phase is greater than 0, the ratio of the change in frequency of the ground oscillation wave is less than 0, and the ratio of the change in amplitude of the ground oscillation wave is less than 0.

[0081] The fault judgment module 23 is also used to determine that the winding of the faulty phase has undergone radial compression when the phase winding is judged to have a deformation fault to ground. If the ratio of the change in capacitance to ground of the faulty phase is less than 0, the ratio of the change in frequency of the ground oscillation wave is greater than 0, and the ratio of the change in amplitude of the ground oscillation wave is greater than 0.

[0082] The three phases of a three-phase transformer are phase A, phase B, and phase C, with the core of phase B located between the cores of phase A and phase C.

[0083] The fault judgment module 23 is also used to determine that the phase that has experienced axial compression or outward tilting is axially compressed when the winding of phase A or phase C is judged to have an interphase deformation fault. If the ratio of the interphase capacitance change of the faulty phase to the other two phases is greater than 0, and the ratio of the interphase oscillation wave frequency change and the interphase oscillation wave amplitude change of the faulty phase to the other two phases is less than 0.

[0084] The fault judgment module 23 is also used to determine that the phase that has experienced axial extension or inward tilting has occurred when the winding of phase A or phase C is judged to have an interphase deformation fault. If the ratio of the interphase capacitance change of the phase that has experienced the fault to the other two phases is less than 0, and the ratio of the interphase oscillation wave frequency change and the interphase oscillation wave amplitude change of the phase that has experienced the fault to the other two phases is greater than 0.

[0085] The fault diagnosis module 23 is also used when it is determined that an interphase deformation fault has occurred in the winding of phase B.

[0086] If the ratio of the phase-to-phase capacitance change between phase B and phase A is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all less than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase C, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial extension on the phase A side.

[0087] If the ratio of the phase-to-phase capacitance change between phase B and phase A is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all greater than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase C, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial compression on the side near phase A.

[0088] If the ratio of the phase-to-phase capacitance change between phase B and phase C is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all less than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase A, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial extension on the phase C side.

[0089] If the ratio of the phase-to-phase capacitance change between phase B and phase C is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all greater than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase A, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that axial compression has occurred on the phase C side of the phase B winding.

[0090] If the ratio of the phase-to-phase capacitance change between phase B and phase A is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are both less than 0, and the ratio of the phase-to-phase capacitance change between phase B and phase C is less than 0, and the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are both greater than 0, then it is determined that the phase B winding has tilted towards the phase A side.

[0091] If the ratio of the phase-to-phase capacitance change between phase B and phase A is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are both greater than 0, and the ratio of the phase-to-phase capacitance change between phase B and phase C is greater than 0, and the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are both less than 0, then it is determined that the phase B winding has tilted towards the phase A side.

[0092] The three-phase transformer winding deformation fault detection device provided in this embodiment of the invention includes a parameter acquisition module that acquires the current parameters of each phase of the transformer at the current moment; a ratio acquisition module that subtracts any current parameter from the corresponding preset standard parameter and then compares the difference with the standard parameter to obtain a ratio; and a fault judgment module that determines whether each phase winding of the transformer has experienced a ground-to-ground deformation fault or a phase-to-phase deformation fault based on this ratio. The detection device provided in this embodiment of the invention uses capacitance, oscillation wave frequency, and oscillation wave amplitude as parameters. The ratio of these parameters reflects whether the distance or the area directly opposite has changed. Therefore, by using two sets of capacitance, oscillation wave frequency, and oscillation wave amplitude for both ground-to-ground and phase-to-phase measurements, it is possible to determine whether the transformer has experienced ground-to-ground and phase-to-phase deformation faults respectively. Furthermore, the ground-to-ground parameter is for each phase, while the phase-to-phase parameter is for two phases, allowing for accurate identification of which phase of the transformer is experiencing the fault. This application's solution, by comparing the current parameters at the current time with preset standard parameters, can quickly determine whether the transformer has experienced a deformation fault, and accurately identify which phase is faulty when a fault occurs. It has the advantages of high sensitivity, good accuracy, and accurate positioning.

[0093] Fourth embodiment: The present invention provides a three-phase transformer winding deformation fault detection system, comprising:

[0094] processor;

[0095] Memory used to store processor-executable instructions;

[0096] The processor is configured to execute the three-phase transformer winding deformation fault detection method provided in the first or second embodiment.

[0097] The three-phase transformer winding deformation fault detection system provided in this invention stores executable instructions for a processor in a memory. When the processor executes these instructions, it first obtains the current parameters of each phase of the transformer at the current moment, then compares these current parameters with preset standard parameters to obtain the ratio of changes. Finally, it determines whether a deformation fault has occurred in the transformer winding based on the ratio of changes. Since the parameters used are capacitance, oscillation frequency, and oscillation amplitude, their ratios can reflect whether the distance or the area directly opposite has changed. Therefore, by using two sets of capacitances to ground and between phases, respectively, it is possible to determine whether the transformer has experienced deformation faults to ground and between phases. Furthermore, the parameters to ground are for each phase, while the parameters between phases are for two phases, allowing for accurate identification of which phase of the transformer is experiencing the fault. This application's solution, by comparing the current parameters at the current time with preset standard parameters, can quickly determine whether a transformer has experienced a deformation fault, and accurately identify which phase is faulty when a fault occurs. It has the advantages of high sensitivity, good accuracy, and accurate positioning.

[0098] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.

[0099] It should be noted that in the description of this application, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this application, unless otherwise stated, "a plurality of" means at least two.

[0100] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the function involved, as will be understood by those skilled in the art to which embodiments of this application pertain.

[0101] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0102] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0103] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0104] The storage media mentioned above can be read-only memory, disk, or optical disk, etc.

[0105] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0106] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A method for detecting winding deformation faults in a three-phase transformer, characterized in that, Includes the following steps: The current parameters of each phase of the transformer at the current moment are obtained. These current parameters include the current capacitance to ground, the current phase-to-phase capacitance, the current frequency of the ground oscillation wave, the current frequency of the phase-to-phase oscillation wave, the current amplitude of the ground oscillation wave, and the current amplitude of the phase-to-phase oscillation wave. The current capacitance to ground is the capacitance to ground of each phase winding of the transformer; the current phase-to-phase capacitance is the phase-to-phase capacitance between each phase winding of the transformer; the current frequency of the ground oscillation wave is the oscillation frequency of the resonant circuit of each phase winding of the transformer to ground; the current frequency of the phase-to-phase oscillation wave is the oscillation frequency of the resonant circuit between each phase winding of the transformer; the current amplitude of the ground oscillation wave is the amplitude of the resonant circuit of each phase winding of the transformer to ground; and the current amplitude of the phase-to-phase oscillation wave is the amplitude of the resonant circuit between each phase winding of the transformer. The difference between any current parameter and the corresponding preset standard parameter is then compared with the standard parameter to obtain a ratio. The ratio includes the ratio of the change in capacitance to ground, the ratio of the change in capacitance between phases, the ratio of the change in the frequency of the ground oscillation wave, the change in the frequency of the phase oscillation wave, the ratio of the change in the amplitude of the ground oscillation wave, and the ratio of the change in the amplitude of the phase oscillation wave. If the absolute values ​​of the ground capacitance change ratio, ground oscillation wave frequency change ratio, and ground oscillation wave amplitude change ratio of any phase are all greater than a first preset value, then the winding of that phase is determined to have a ground deformation fault; if the absolute values ​​of the ground capacitance change ratio, ground oscillation wave frequency change ratio, and ground oscillation wave amplitude change ratio of any phase are all less than the first preset value, then the winding of the transformer is determined not to have a ground deformation fault; and / or, if the absolute values ​​of the phase-to-phase capacitance change ratio, phase-to-phase oscillation wave frequency change ratio, and phase-to-phase oscillation wave amplitude change ratio between any phase and at least one of the other two phases are all greater than a second preset value, then the winding of that phase is determined to have a phase-to-phase deformation fault; if the absolute values ​​of the phase-to-phase capacitance change ratio, phase-to-phase oscillation wave frequency change ratio, and phase-to-phase oscillation wave amplitude change ratio between any phase and the other two phases are all less than the second preset value, then the winding of that phase is determined not to have a phase-to-phase deformation fault.

2. The method according to claim 1, characterized in that, Also includes: When it is determined that the winding of the phase has a deformation fault to ground, if the ratio of the change in capacitance to ground of the faulty phase is greater than 0, the ratio of the change in frequency of the ground oscillation wave is less than 0, and the ratio of the change in amplitude of the ground oscillation wave is less than 0, then it is determined that the winding of the faulty phase has undergone radial extension or tilting.

3. The method according to claim 1, characterized in that, Also includes: When it is determined that the winding of the phase has a deformation fault to ground, if the ratio of the change in capacitance to ground of the faulty phase is less than 0, the ratio of the change in frequency of the ground oscillation wave is greater than 0, and the ratio of the change in amplitude of the ground oscillation wave is greater than 0, then it is determined that the winding of the faulty phase has undergone radial compression.

4. The method according to claim 1, characterized in that, Also includes: The three phases of the three-phase transformer are phase A, phase B and phase C, wherein the core of phase B is located between the core of phase A and the core of phase C; When it is determined that a phase-to-phase deformation fault has occurred in the winding of phase A or phase C, if the ratio of the phase-to-phase capacitance change of the faulty phase to the other two phases is greater than 0, and the ratio of the phase-to-phase oscillation wave frequency change and the phase-to-phase oscillation wave amplitude change of the faulty phase to the other two phases is less than 0, then it is determined that the faulty phase has undergone axial compression or outward tilting.

5. The method according to claim 1, characterized in that, Also includes: The three phases of the three-phase transformer are phase A, phase B and phase C, wherein the core of phase B is located between the core of phase A and the core of phase C; When it is determined that a phase-to-phase deformation fault has occurred in the winding of phase A or phase C, if the ratio of the phase-to-phase capacitance change of the faulty phase to the other two phases is less than 0, and the ratio of the phase-to-phase oscillation wave frequency change and the phase-to-phase oscillation wave amplitude change of the faulty phase to the other two phases is greater than 0, then it is determined that the faulty phase has undergone axial extension or inward tilting.

6. The method according to claim 1, characterized in that, Also includes: The three-phase transformer has three phases: phase A, phase B, and phase C. The core of phase B is located between the cores of phase A and phase C. When it is determined that an interphase deformation fault has occurred in the winding of phase B, If the ratio of the phase-to-phase capacitance change between phase B and phase A is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all less than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase C, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial extension on the phase A side. If the ratio of the phase-to-phase capacitance change between phase B and phase A is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are all greater than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase C, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial compression on the phase A side. If the ratio of the phase-to-phase capacitance change between phase B and phase C is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all less than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase A, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial extension on the phase C side. If the ratio of the phase-to-phase capacitance change between phase B and phase C is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are all greater than 0, and the absolute values ​​of the ratio of the phase-to-phase capacitance change between phase B and phase A, the ratio of the phase-to-phase oscillation wave frequency change, and the ratio of the phase-to-phase oscillation wave amplitude change are all less than the second preset value, then it is determined that the phase B winding has undergone axial compression on the phase C side.

7. The method according to claim 1, characterized in that, Also includes: The three-phase transformer has three phases: phase A, phase B, and phase C. The core of phase B is located between the cores of phase A and phase C. When it is determined that an interphase deformation fault has occurred in the winding of phase B, If the ratio of the phase-to-phase capacitance change between phase B and phase A is greater than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are both less than 0, and the ratio of the phase-to-phase capacitance change between phase B and phase C is less than 0, and the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are both greater than 0, then it is determined that the phase B winding has tilted towards the phase A side. If the ratio of the phase-to-phase capacitance change between phase B and phase A is less than 0, the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase A and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase A are both greater than 0, and the ratio of the phase-to-phase capacitance change between phase B and phase C is greater than 0, and the ratio of the phase-to-phase oscillation wave frequency change between phase B and phase C and the ratio of the phase-to-phase oscillation wave amplitude change between phase B and phase C are both less than 0, then it is determined that the phase B winding has tilted towards the phase C side.

8. The method according to claim 1, characterized in that, Also includes: When the product of the ratio of the change in capacitance to ground of any phase with the ratio of the change in frequency of its ground oscillation wave or the ratio of the change in amplitude of its ground oscillation wave is greater than 0, the data of that phase is judged to be abnormal. When the product of the ratio of the frequency change of the ground oscillation wave of any phase to the ratio of the amplitude change of the ground oscillation wave is less than 0, the data of that phase is judged to be abnormal. When the product of the ratio of the phase capacitance change between any two phases and the ratio of the phase oscillation frequency change or the ratio of the phase oscillation amplitude change between the two phases is greater than 0, the data between the two phases is judged to be abnormal. When the product of the ratio of the frequency change of the interphase oscillation wave between any two phases and the ratio of the amplitude change of the interphase oscillation wave between the two phases is less than 0, the data between the two phases is judged to be abnormal.

9. A three-phase transformer winding deformation fault detection device, characterized in that, include: The parameter acquisition module is used to acquire the current parameters of each phase of the transformer at the current moment. The current parameters include the current ground capacitance, current phase-to-phase capacitance, current ground oscillation frequency, current phase-to-phase oscillation frequency, current ground oscillation amplitude, and current phase-to-phase oscillation amplitude. The current ground capacitance is the ground capacitance of each phase winding of the transformer; the current phase-to-phase capacitance is the phase-to-phase capacitance between each phase winding of the transformer; the current ground oscillation frequency is the oscillation frequency of the resonant circuit of each phase winding of the transformer to ground; the current phase-to-phase oscillation frequency is the oscillation frequency of the resonant circuit between each phase winding of the transformer; the current ground oscillation amplitude is the oscillation amplitude of the resonant circuit of each phase winding of the transformer to ground; and the current phase-to-phase oscillation amplitude is the oscillation amplitude of the resonant circuit between each phase winding of the transformer. The ratio acquisition module is used to calculate the difference between any current parameter and the corresponding preset standard parameter, and then compare the difference with the standard parameter to obtain a ratio. The ratio includes the ground capacitance change ratio, the phase-to-phase capacitance change ratio, the ground oscillation wave frequency change ratio, the phase-to-phase oscillation wave frequency change value, the ground oscillation wave amplitude change ratio, and the phase-to-phase oscillation wave amplitude change ratio. The fault judgment module is configured to determine that the winding of any phase has a ground deformation fault if the absolute values ​​of the ground capacitance change ratio, the ground oscillation wave frequency change ratio, and the ground oscillation wave amplitude change ratio of any phase are all greater than a first preset value; and to determine that the winding of the transformer has not experienced a ground deformation fault if the absolute values ​​of the ground capacitance change ratio, the ground oscillation wave frequency change ratio, and the ground oscillation wave amplitude change ratio of any phase are all less than the first preset value; and / or, to determine that the winding of any phase has an interphase deformation fault if the absolute values ​​of the interphase capacitance change ratio, the interphase oscillation wave frequency change ratio, and the interphase oscillation wave amplitude change ratio of any phase and at least one of the other two phases are all greater than a second preset value; and to determine that the winding of any phase has not experienced an interphase deformation fault if the absolute values ​​of the interphase capacitance change ratio, the interphase oscillation wave frequency change ratio, and the interphase oscillation wave amplitude change ratio of any phase and the other two phases are all less than the second preset value.

10. A three-phase transformer winding deformation fault detection system, characterized in that, include: processor; Memory used to store the processor's executable instructions; The processor is configured to perform the method according to any one of claims 1-8.

Images