A method and system for evaluating the short-circuit electromagnetic force impact resistance of a transformer insulating pad

Abstract

The application discloses a kind of transformer insulating pad anti-short-circuit electromagnetic force impact evaluation method and system, method includes: obtaining the transformer insulating pad to be measured, and test the first performance parameter of transformer insulating pad to be measured;The short-circuit electromagnetic force impact test condition of configuration transformer insulating pad to be measured;Wherein, transformer insulating pad to be measured corresponds to several short-circuit electromagnetic force impact test conditions;Each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval and an electromagnetic impact force number;According to short-circuit electromagnetic force impact test condition, simulate short-circuit electromagnetic force impact test to transformer insulating pad to be measured, test second performance parameter, and compare second performance parameter with first performance parameter, obtain total comparison result;According to total comparison result, determine the anti-short-circuit electromagnetic force capacity of transformer insulating pad to be measured, by implementing the application, reduce transformer insulating pad anti-short-circuit electromagnetic force impact evaluation cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of transformer short-circuit resistance, and in particular to a transformer insulation pad short-circuit electromagnetic force impact evaluation method and system. BACKGROUND

[0002] In a power system, a transformer is one of the key electrical equipment, and its reliability is directly related to the safe operation of the entire system. When the transformer winding is subjected to dynamic short-circuit electromagnetic force impact, axial and auxiliary instability and tangential torsion may occur, causing insulation pad misplacement, shedding and support bar collapse, and in severe cases, insulation layer damage. The result of dynamic short-circuit electromagnetic force impact will change the insulation distance between conductors of different potentials, and voltage breakdown may occur, causing electrical short circuit between turns, layers or windings.

[0003] Currently, the evaluation of the short-circuit resistance of transformer insulation pads is mainly through short-circuit current impact test on the transformer body to test the short-circuit resistance of transformer insulation pads, but the short-circuit current impact test has very high requirements for test conditions and test costs, and cannot be widely applied. SUMMARY

[0004] The embodiment of the present application provides a transformer insulation pad short-circuit electromagnetic force impact evaluation method, which can effectively solve the problem of high requirements for test conditions and test costs in the short-circuit current impact test of the prior art.

[0005] An embodiment of the present application provides a transformer insulation pad short-circuit electromagnetic force impact evaluation method, comprising:

[0006] Obtaining a transformer insulation pad to be tested, and testing a first performance parameter of the transformer insulation pad to be tested for representing initial performance;

[0007] Configuring short-circuit electromagnetic force impact test conditions of the transformer insulation pad to be tested; wherein the transformer insulation pad to be tested corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval and an electromagnetic impact force number;

[0008] According to the short-circuit electromagnetic force impact test conditions corresponding to the transformer insulation pad to be tested, the transformer insulation pad to be tested is subjected to simulated short-circuit electromagnetic force impact test;

[0009] Testing a second performance parameter of the transformer insulation pad to be tested subjected to the simulated short-circuit electromagnetic force impact test, and comparing the second performance parameter of the transformer insulation pad to be tested with the first performance parameter to obtain a total comparison result for representing performance change; and determining the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested according to the total comparison result.

[0010] Further, in the case that the first performance parameter is a mechanical performance parameter, the determination of the anti-short-circuit electromagnetic force capability of the transformer insulating pad to be tested comprises:

[0011] comparing the first mechanical performance parameter used to represent the transformer insulating pad to be tested before the simulated short-circuit electromagnetic force impact test with the second mechanical performance parameter used to represent the transformer insulating pad after the simulated short-circuit electromagnetic force impact test, to obtain a first comparison result in the total comparison result used to represent the change in the mechanical performance of the transformer insulating pad to be tested;

[0012] determining the anti-short-circuit capability of the transformer insulating pad to be tested according to the first comparison result.

[0013] Further, in the case that the first performance parameter is an appearance structure parameter, the determination of the anti-short-circuit electromagnetic force capability of the transformer insulating pad to be tested comprises:

[0014] comparing the first appearance structure parameter used to represent the transformer insulating pad to be tested before the simulated short-circuit electromagnetic force impact test with the second appearance structure parameter used to represent the transformer insulating pad after the simulated short-circuit electromagnetic force impact test, to obtain a second comparison result in the total comparison result used to represent the change in the appearance structure of the transformer insulating pad to be tested;

[0015] determining the anti-short-circuit electromagnetic force capability of the transformer insulating pad to be tested according to the second comparison result.

[0016] Further, the first mechanical performance parameter comprises a first pressure waveform and a first pressure value, and the second mechanical performance parameter comprises a second pressure waveform and a second pressure value.

[0017] comparing the first mechanical performance parameter used to represent the transformer insulating pad to be tested before the simulated short-circuit electromagnetic force impact test with the second mechanical performance parameter used to represent the transformer insulating pad after the simulated short-circuit electromagnetic force impact test comprises:

[0018] comparing the second pressure waveform and the second pressure value of the transformer insulating pad to be tested after the simulated short-circuit electromagnetic force impact test with the initial first pressure waveform and the initial first pressure value of the transformer insulating pad to be tested, respectively.

[0019] Further, the first appearance structure parameter comprises a first deformation amount, a first thickness and a first area, and the second appearance structure parameter comprises a second deformation amount, a second thickness and a second area.

[0020] comparing the first appearance structure parameter used to represent the transformer insulating pad to be tested before the simulated short-circuit electromagnetic force impact test with the second appearance structure parameter used to represent the transformer insulating pad after the simulated short-circuit electromagnetic force impact test comprises:

[0021] The first deformation variable, the first thickness and the first area of the transformer insulation pad to be tested before the simulated short-circuit electromagnetic force impact test are compared with the second deformation variable, the second thickness and the second area after the simulated short-circuit electromagnetic force impact test.

[0022] Further, the short-circuit electromagnetic force impact test condition includes: a first test condition for representing a static electromagnetic impact force test, a second test condition for representing a dynamic electromagnetic impact force test, and a third test condition for representing a static electromagnetic impact force test after the dynamic electromagnetic impact force test;

[0023] The electromagnetic impact force amplitude corresponding to the first test condition is consistent with the electromagnetic impact force amplitude corresponding to the third test condition;

[0024] The electromagnetic impact force frequency corresponding to the first test condition is consistent with the electromagnetic impact force frequency corresponding to the third test condition.

[0025] Further, the electromagnetic impact force corresponding to the second test condition presents a periodic change;

[0026] The calculation of the electromagnetic impact force corresponding to the second test condition includes:

[0027] The electromagnetic impact force corresponding to the second test condition is calculated according to the electromagnetic impact force amplitude corresponding to the second test condition, a preset electromagnetic impact force frequency and a preset periodic interval.

[0028] Further, it further includes: before the simulated short-circuit electromagnetic force impact test on the transformer insulation pad to be tested, oil immersion treatment is performed.

[0029] Further, the transformer insulation pad to be tested is composed of a plurality of insulation paper boards with consistent thickness.

[0030] As an improvement of the above-mentioned scheme, another embodiment of the present application correspondingly provides a transformer insulation pad short-circuit electromagnetic force impact resistance evaluation system, which comprises:

[0031] The pad parameter acquisition module is configured to acquire the transformer insulation pad to be tested and test the first performance parameter of the transformer insulation pad to be tested for representing the initial performance.

[0032] The condition configuration module is configured to configure the short-circuit electromagnetic force impact test condition of the transformer insulation pad to be tested; wherein the transformer insulation pad to be tested corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval and an electromagnetic impact force frequency.

[0033] The simulation test module is configured to simulate short-circuit electromagnetic force impact test on the transformer insulation pad to be tested according to the short-circuit electromagnetic force impact test condition corresponding to the transformer insulation pad to be tested.

[0034] The insulation pad evaluation module is configured to test the second performance parameter of the transformer insulation pad to be tested after the simulation short-circuit electromagnetic force impact test, compare the second performance parameter of the transformer insulation pad to be tested with the first performance parameter, and obtain a total comparison result for indicating performance change; and determine the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested according to the total comparison result.

[0035] By implementing the present application, at least the following beneficial effects are achieved:

[0036] The present application provides a transformer insulation pad short-circuit electromagnetic force impact evaluation method, which can obtain a transformer insulation pad to be tested, test a first performance parameter of the transformer insulation pad to be tested for indicating initial performance, configure a short-circuit electromagnetic force impact test condition of the transformer insulation pad to be tested, wherein the transformer insulation pad to be tested corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval, and an electromagnetic impact force number; simulate short-circuit electromagnetic force impact test on the transformer insulation pad to be tested according to the short-circuit electromagnetic force impact test condition corresponding to the transformer insulation pad to be tested; test a second performance parameter of the transformer insulation pad to be tested after the simulation short-circuit electromagnetic force impact test, compare the second performance parameter of the transformer insulation pad to be tested with the first performance parameter, and obtain a total comparison result for indicating performance change; and determine the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested according to the total comparison result. By simulating short-circuit electromagnetic force impact test on the transformer insulation pad, the transformer body is not directly impacted for test, the configured short-circuit electromagnetic force impact test condition can simulate the working environment of the transformer insulation pad under normal operation, the transformer insulation pad to be tested is simulated for short-circuit electromagnetic force impact test through the short-circuit electromagnetic force impact test condition, the specific performance change of the insulation pad after being subjected to short-circuit electromagnetic force impact can be obtained by comparing the first performance parameter and the second performance parameter, so as to determine the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested according to the first comparison result. The test condition requirement is not high, the test cost is low, and large-scale popularization and application can be carried out. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is a flowchart of a transformer insulation pad short-circuit electromagnetic force impact evaluation method provided by an embodiment of the present application;

[0038] Figure 2A schematic diagram of a transformer insulation pad to be tested in a method for evaluating the anti-short-circuit electromagnetic force impact of a transformer insulation pad according to an embodiment of the present application;

[0039] Figure 3 A pressure waveform diagram in a method for evaluating the anti-short-circuit electromagnetic force impact of a transformer insulation pad according to an embodiment of the present application;

[0040] Figure 4 A short-circuit current waveform diagram in a method for evaluating the anti-short-circuit electromagnetic force impact of a transformer insulation pad according to an embodiment of the present application;

[0041] Figure 5 A structural schematic diagram of a system for evaluating the anti-short-circuit electromagnetic force impact of a transformer insulation pad according to an embodiment of the present application. DETAILED DESCRIPTION

[0042] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application; the description and the claims of the present application and the above description of the drawings, the terms "comprising" and "having" and any variations thereof are intended to cover not exclusively inclusive.

[0044] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0045] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, or necessarily alternatives to other embodiments. It will be explicitly and implicitly appreciated by those of ordinary skill in the art that embodiments described herein can be combined with other embodiments.

[0046] In the description of the embodiments of the present application, the term "and / or" is only to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are in an "or" relationship.

[0047] In the description of the embodiments of the present application, the term "a plurality of" refers to two or more (including two), and similarly, "a plurality of groups" refers to two or more groups (including two groups), and "a plurality of pieces" refers to two or more pieces (including two pieces).

[0048] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanical connection, or it can be electrical connection; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0049] Reference Figure 1 is a flowchart of a transformer insulation pad short-circuit electromagnetic force impact evaluation method provided by an embodiment of the present application, which comprises:

[0050] S1, obtaining a transformer insulation pad to be tested, and testing a first performance parameter of the transformer insulation pad to be tested for indicating initial performance;

[0051] S2, configuring short-circuit electromagnetic force impact test conditions of the transformer insulation pad to be tested; wherein the transformer insulation pad to be tested corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval and an electromagnetic impact force number;

[0052] S3, performing simulated short-circuit electromagnetic force impact test on the transformer insulation pad to be tested according to the short-circuit electromagnetic force impact test conditions corresponding to the transformer insulation pad to be tested;

[0053] S4, testing a second performance parameter of the transformer insulation pad to be tested after the simulated short-circuit electromagnetic force impact test, and comparing the second performance parameter of the transformer insulation pad to be tested with the first performance parameter to obtain a total comparison result for indicating performance change; determining the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested according to the total comparison result.

[0054] Specifically, the initial performance of the transformer insulation pad to be tested is tested before the test to obtain the first performance parameter, which is convenient for comparison with the test results afterwards. The short-circuit electromagnetic force impact test conditions are configured by configuring different electromagnetic impact force amplitudes, electromagnetic impact force time intervals and electromagnetic impact force times to simulate the environmental conditions in which the transformer insulation pad is in working state.

[0055] In a preferred embodiment of the present application, the transformer insulation pad to be tested is obtained, and the first performance parameter representing the initial performance of the transformer insulation pad to be tested is tested, and then the short-circuit electromagnetic force impact test conditions of the transformer insulation pad to be tested are configured; wherein the transformer insulation pad to be tested corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval and an electromagnetic impact force time; then the transformer insulation pad to be tested is subjected to a simulated short-circuit electromagnetic force impact test according to the short-circuit electromagnetic force impact test conditions corresponding to the transformer insulation pad to be tested; then the second performance parameter of the transformer insulation pad to be tested after the simulated short-circuit electromagnetic force impact test is tested, and the second performance parameter of the transformer insulation pad to be tested is compared with the first performance parameter to obtain a total comparison result representing the performance change, and finally the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested is determined according to the total comparison result. By comparing the first performance parameter and the second performance parameter, the performance change of the transformer insulation pad to be tested after the simulated short-circuit electromagnetic force impact test can be understood, which helps to evaluate its short-circuit electromagnetic force resistance. If the performance is found to decrease significantly, the design of the insulation pad can be optimized to improve its short-circuit electromagnetic force resistance, to ensure that the transformer insulation pad has good short-circuit electromagnetic force resistance, to reduce the risk of accidents caused by short-circuit, and to improve the reliability and stability of the entire transformer system.

[0056] Preferably, in the case where the first performance parameter is a mechanical performance parameter, the determination of the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested comprises:

[0057] comparing the first mechanical performance parameter representing the transformer insulation pad to be tested before the simulated short-circuit electromagnetic force impact test with the second mechanical performance parameter representing the transformer insulation pad to be tested after the simulated short-circuit electromagnetic force impact test to obtain a first comparison result in the total comparison result representing the mechanical performance change of the transformer insulation pad to be tested;

[0058] determining the short-circuit resistance of the transformer insulation pad to be tested according to the first comparison result.

[0059] Preferably, in the case where the first performance parameter is an appearance structure parameter, the determination of the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested comprises:

[0060] The first appearance structure parameter used for representing the first appearance structure of the transformer insulation pad before the simulated short-circuit electromagnetic force impact test is compared with the second appearance structure parameter used for representing the second appearance structure after the simulated short-circuit electromagnetic force impact test, and a second comparison result used for representing the appearance structure change of the transformer insulation pad is obtained from a total comparison result.

[0061] The short-circuit electromagnetic force resistance of the transformer insulation pad is determined according to the second comparison result.

[0062] In a preferred embodiment of the present application, the mechanical property of the transformer insulation pad may change after the simulated short-circuit electromagnetic force impact test, so in order to evaluate the accuracy of the short-circuit electromagnetic force resistance of the transformer insulation pad, the first mechanical property parameter used for representing the first mechanical property of the transformer insulation pad before the simulated short-circuit electromagnetic force impact test is recorded, and the second mechanical property parameter used for representing the second mechanical property after the simulated short-circuit electromagnetic force impact test is recorded, then the first mechanical property parameter and the second mechanical property parameter are compared, a first comparison result used for representing the mechanical property change of the transformer insulation pad is obtained from a total comparison result, and finally the short-circuit electromagnetic force resistance of the transformer insulation pad is determined according to the first comparison result. By comparing the change of the mechanical property parameter, the mechanical property change of the insulation pad under the short-circuit electromagnetic force impact can be quickly identified, so as to improve the test efficiency and the evaluation efficiency of the short-circuit electromagnetic force resistance of the transformer insulation pad.

[0063] In a preferred embodiment of the present application, the transformer insulation pad may be deformed after the simulated short-circuit electromagnetic force impact test, so in order to evaluate the accuracy of the short-circuit electromagnetic force resistance of the transformer insulation pad, the first appearance structure parameter used for representing the first appearance structure of the transformer insulation pad before the simulated short-circuit electromagnetic force impact test is recorded, and the second appearance structure parameter used for representing the second appearance structure after the simulated short-circuit electromagnetic force impact test is recorded, then the first appearance structure parameter and the second appearance structure parameter are compared, a second comparison result used for representing the appearance structure change of the transformer insulation pad is obtained from a total comparison result, and finally the short-circuit electromagnetic force resistance of the transformer insulation pad is determined according to the second comparison result. By comparing the change of the appearance structure parameter, the structure change of the insulation pad under the short-circuit electromagnetic force impact can be quickly identified, so as to improve the test efficiency and the evaluation efficiency of the short-circuit electromagnetic force resistance of the transformer insulation pad.

[0064] Specifically, the first mechanical property parameter includes a first pressure waveform and a first pressure value, and the second mechanical property parameter includes a second pressure waveform and a second pressure value.

[0065] comparing the first mechanical performance parameter used to represent the first mechanical performance of the transformer insulation pad to be tested before the simulated short-circuit electromagnetic force impact test with the second mechanical performance parameter used to represent the second mechanical performance after the simulated short-circuit electromagnetic force impact test, comprising:

[0066] comparing the second pressure waveform and the second pressure value of the transformer insulation pad to be tested after the simulated short-circuit electromagnetic force impact test with the initial first pressure waveform and the first pressure value of the transformer insulation pad to be tested.

[0067] In a preferred embodiment of the present application, the first pressure value represents the pressure value of the insulation pad during the force process when a small pressure is applied to the transformer insulation pad to be tested before the simulated test; and the first pressure waveform represents the whole process of the pressure applied to the insulation pad from the beginning to the final stable or peak value before the simulated test. The first performance parameter can ensure that the insulation pad is in a normal state before the simulated test, and that the evaluation result is not inaccurate due to external factors such as material defects or material unqualification. The second pressure value represents the pressure value during the simulated test; and the second pressure waveform represents the whole process of the large electromagnetic impact force applied to the insulation pad from the beginning to the final stable or peak value during the simulated test, which can reveal the response characteristics of the insulation pad when it is impacted. Comparing the first pressure value with the second pressure value can intuitively understand the change of the maximum pressure that the insulation pad can withstand before and after the short-circuit electromagnetic force impact. This helps to determine whether the insulation pad has performance degradation during the test or whether it can maintain its original pressure-bearing capacity. Comparing the first pressure waveform with the second pressure waveform can more detailedly analyze the dynamic response of the insulation pad during the impact process, including the deformation rate and recovery of the insulation pad when it is under stress. These information is crucial for predicting the performance of the insulation pad in actual operation.

[0068] Preferably, the first appearance structure parameter comprises a first deformation amount, a first thickness and a first area; and the second appearance structure parameter comprises a second deformation amount, a second thickness and a second area.

[0069] comparing the first appearance structure parameter used to represent the first appearance structure of the transformer insulation pad to be tested before the simulated short-circuit electromagnetic force impact test with the second appearance structure parameter used to represent the second appearance structure after the simulated short-circuit electromagnetic force impact test, comprising:

[0070] comparing the first deformation amount, the first thickness and the first area of the transformer insulation pad to be tested before the simulated short-circuit electromagnetic force impact test with the second deformation amount, the second thickness and the second area after the simulated short-circuit electromagnetic force impact test, respectively.

[0071] In a preferred embodiment of the present application, the first deformation refers to the deformation of the insulating pad before the simulation test; the first thickness refers to the thickness of the insulating pad before the simulation test; and the first area refers to the area of the insulating pad before the simulation test. The second deformation refers to the deformation of the insulating pad after the simulation test; the second thickness refers to the thickness of the insulating pad after the simulation test; and the second area refers to the area of the insulating pad after the simulation test. The first deformation, the first thickness and the first area of the insulating pad of the transformer to be tested before the simulation short-circuit electromagnetic force impact test are compared with the second deformation, the second thickness and the second area after the simulation short-circuit electromagnetic force impact test, respectively, to obtain a second comparison result for indicating the change in appearance structure. By comparing the changes in deformation, thickness and area, the structural change of the insulating pad under the short-circuit electromagnetic force impact can be more accurately evaluated.

[0072] Illustratively, the short-circuit electromagnetic force impact test conditions include: a first test condition for indicating a static electromagnetic impact force test, a second test condition for indicating a dynamic electromagnetic impact force test, and a third test condition for indicating a static electromagnetic impact force test after the dynamic electromagnetic impact force test.

[0073] Specifically, the electromagnetic impact force amplitude corresponding to the first test condition is consistent with the electromagnetic impact force amplitude corresponding to the third test condition.

[0074] Specifically, the number of electromagnetic impact forces corresponding to the first test condition is consistent with the number of electromagnetic impact forces corresponding to the third test condition.

[0075] Specifically, the electromagnetic impact force corresponding to the second test condition presents a periodic change.

[0076] The calculation of the electromagnetic impact force corresponding to the second test condition includes:

[0077] The electromagnetic impact force corresponding to the second test condition is calculated according to the electromagnetic impact force amplitude corresponding to the second test condition, a preset electromagnetic impact force frequency and a preset periodic interval.

[0078] In a preferred embodiment of the present invention, configuring the short-circuit electromagnetic force impact test conditions includes three stages: first, configuring a first test condition representing a static electromagnetic force impact test; second, configuring a second test condition representing a dynamic electromagnetic force impact test; and third, configuring a third test condition representing a static electromagnetic force impact test after the dynamic electromagnetic force impact test. The electromagnetic force impact amplitude corresponding to the first test condition is consistent with the electromagnetic force impact amplitude corresponding to the third test condition, and the number of electromagnetic force impacts corresponding to the first test condition is consistent with the number of electromagnetic force impacts corresponding to the third test condition. That is, the electromagnetic force magnitude and impact times corresponding to the first and third test conditions are consistent. Under the first test condition, the insulating spacer is initially subjected to the applied electromagnetic force. After testing under the second test condition, under the third test condition, to eliminate the cumulative effect of the applied force, the electromagnetic force amplitude and impact times corresponding to the third test condition are consistent, thereby obtaining more accurate insulating spacer comparison results. The electromagnetic force impact corresponding to the second test condition exhibits periodic variations, simulating the electromotive force generated by an equivalent short-circuit current. This is applied to the insulating spacer, achieving the effect of a dynamic force impact on the transformer insulating spacer.

[0079] Preferably, the insulating spacer of the transformer to be tested is subjected to oil immersion treatment before the simulated short-circuit electromagnetic force impact test is performed.

[0080] Preferably, the insulating spacer of the transformer to be tested is composed of a plurality of insulating cardboards of uniform thickness stacked together.

[0081] In a preferred embodiment of the present invention, an insulating paperboard with a thickness of 1.5 mm or 2 mm is selected. Figure 2 As shown, the test blocks are cut into several sizes, such as 30×30 mm. The test blocks are then stacked in multiple layers (10-15 mm thick) and dried under pressure for 5 minutes. The blocks are then dried in kerosene vapor phase under pressure at 110°C for 36 hours at a vacuum of 30 Pa. After drying, the insulating blocks are again pressurized at 35 kg / cm². The test blocks are then immersed in transformer oil in a container and left to stand for 24 hours to obtain the transformer insulating blocks to be tested. The transformer insulating blocks to be tested are then placed in a fatigue testing machine capable of loading an adjustable pressure waveform.

[0082] In a preferred embodiment of the present application, a steady-state force of 2 MPa, i.e. Fs=1.8 kN, is applied to the transformer insulation pad to be tested according to the first test condition (electromagnetic impact force amplitude 2 MPa, electromagnetic impact force time interval 1 minute, electromagnetic impact force number 1), and the deformation, thickness, area, pressure value and pressure waveform of the insulation pad after the first test condition test are recorded. Then a dynamic force of Fm / 2+Fm / 2*sin(2*pi*f*t) is applied to the transformer insulation pad to be tested according to the second test condition (electromagnetic impact force amplitude Fm, electromagnetic impact force time interval 20 ms, electromagnetic impact force number 9), where Fm is the peak value of the dynamic force, f is the frequency of the dynamic force waveform, and t is the time. The dynamic electromagnetic impact force parameters applied to the transformer insulation pad to be tested are shown in Table 1. The test lasts for 9 cycles, and the deformation, thickness, area, pressure value and pressure waveform of the transformer insulation pad to be tested under the second test condition are recorded.

[0083] Table 1

[0084]

[0085]

[0086] Then a steady-state force of 2 MPa, i.e. Fs=1.8 kN, is applied to the transformer insulation pad to be tested according to the third test condition (electromagnetic impact force amplitude 2 MPa, electromagnetic impact force time interval 2 minutes, electromagnetic impact force number 1), and the deformation, thickness, area, pressure value and pressure waveform of the insulation pad under the third test condition are recorded, i.e. the final second deformation, second thickness, second area, second pressure value and second pressure waveform are obtained. The first test condition is the first time that the force is applied to the transformer insulation pad to be tested, and the third test condition is the force applied to the transformer insulation pad to be tested under 9 cycles, so as to eliminate the influence of the cumulative effect of the force, and the electromagnetic impact force time interval of the third test condition is longer, so as to obtain the final stable data. Figure 3 It can be seen that except for the first cycle and the set value, the other cycle dynamic pressure waveform is consistent with the set parameter value, verifying the effectiveness and practicability of the simulation of the dynamic short-circuit electromagnetic force impact test of the transformer insulation pad. At the same time, the amplitude of the dynamic short-circuit force that the pad can withstand can be determined by adjusting the size of Fm.

[0087] Specifically, in the prior art, the anti-short-circuit capability of the transformer insulation pad is theoretically checked. Since the existing checking method lacks dynamic short-circuit electromagnetic force test data support, it is difficult to accurately reflect the dynamic characteristics of the insulation pad during the short-circuit process, and the effectiveness of the theoretical checking of the anti-short-circuit capability of the transformer insulation pad cannot be guaranteed. Under the short-circuit working condition of the transformer, a larger short-circuit current will flow in the winding, and the short-circuit current waveform is as followsFigure 4 It is a periodic and decaying waveform (tends to be stable after several cycles). Short-circuit current in the winding will produce a huge electromagnetic force, the electromagnetic force of transformer winding can be decomposed into radial short-circuit force and axial short-circuit force, usually the transformer short-circuit dynamic characteristic refers to the change process caused by axial force. The calculation expression of electromagnetic force is F=BI d L, wherein B is the leakage magnetic of winding, which depends on short-circuit current I d Size and spatial position of winding, L is the length of winding. The structure of transformer winding and insulating pad can be equivalent to "mass-spring" model, the axial force on the transformer winding is transmitted to the insulating pad, the dynamic change of axial force causes the dynamic change of insulating pad, and it is possible to cause mechanical damage of insulating pad, thereby causing the performance of short-circuit resistance of pad to decline, resulting in internal fault. The embodiment sets a dynamic force changing with time, simulates the electromagnetic force generated by equivalent short-circuit current, and applies to the insulating pad, so as to achieve the effect of the insulating pad of the transformer being impacted by the dynamic force.

[0088] By implementing the embodiment, the transformer insulating pad to be tested is obtained, and a first performance parameter for indicating initial performance of the transformer insulating pad to be tested is tested; a short-circuit electromagnetic force impact test condition of the transformer insulating pad to be tested is configured; wherein the transformer insulating pad to be tested corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval, and an electromagnetic impact force number; the transformer insulating pad to be tested is subjected to a simulated short-circuit electromagnetic force impact test according to the short-circuit electromagnetic force impact test condition corresponding to the transformer insulating pad to be tested; a second performance parameter of the transformer insulating pad to be tested subjected to the simulated short-circuit electromagnetic force impact test is tested, and the second performance parameter of the transformer insulating pad to be tested is compared with the first performance parameter to obtain a first comparison result for indicating performance change; and the short-circuit electromagnetic force resistance of the transformer insulating pad to be tested is determined according to the first comparison result. By subjecting the transformer insulating pad to the simulated short-circuit electromagnetic force impact test, the transformer body is not directly subjected to impact test, the configured short-circuit electromagnetic force impact test condition can simulate the working environment of the transformer insulating pad under normal operation, the transformer insulating pad to be tested is subjected to the simulated short-circuit electromagnetic force impact test through the short-circuit electromagnetic force impact test condition, the specific change of performance of the insulating pad after being subjected to the short-circuit electromagnetic force impact can be obtained by comparing the first performance parameter and the second performance parameter, and the short-circuit electromagnetic force resistance of the transformer insulating pad to be tested is determined according to the first comparison result. The requirement of test condition is not high, the cost of test is low, and large-scale popularization and application can be carried out.

[0089] Referring to Figure 5 It is a structure schematic diagram of a transformer insulating pad short-circuit electromagnetic force impact evaluation system provided by an embodiment of the present application, comprising:

[0090] a cushion parameter acquisition module, configured to acquire a to-be-tested transformer insulation cushion and test a first performance parameter of the to-be-tested transformer insulation cushion, the first performance parameter being used to represent an initial performance;

[0091] a condition configuration module, configured to configure a short-circuit electromagnetic force impact test condition of the to-be-tested transformer insulation cushion; wherein the to-be-tested transformer insulation cushion corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval, and an electromagnetic impact force number;

[0092] a simulation test module, configured to perform a simulation short-circuit electromagnetic force impact test on the to-be-tested transformer insulation cushion according to the short-circuit electromagnetic force impact test condition corresponding to the to-be-tested transformer insulation cushion;

[0093] an insulation cushion evaluation module, configured to test a second performance parameter of the to-be-tested transformer insulation cushion after the simulation short-circuit electromagnetic force impact test, compare the second performance parameter of the to-be-tested transformer insulation cushion with the first performance parameter, and obtain a total comparison result used to represent a performance change; and determine an anti-short-circuit electromagnetic force capability of the to-be-tested transformer insulation cushion according to the total comparison result.

[0094] The application provides a transformer insulation pad short-circuit electromagnetic force impact resistance evaluation system, a transformer insulation pad to be measured is acquired by a pad parameter acquisition module, and a first performance parameter for representing initial performance of the transformer insulation pad to be measured is tested; a short-circuit electromagnetic force impact test condition of the transformer insulation pad to be measured is configured by a condition configuration module; wherein the transformer insulation pad to be measured corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval and an electromagnetic impact force number; in a simulation test module, the transformer insulation pad to be measured is subjected to a simulated short-circuit electromagnetic force impact test according to the short-circuit electromagnetic force impact test condition corresponding to the transformer insulation pad to be measured; a second performance parameter of the transformer insulation pad to be measured subjected to the simulated short-circuit electromagnetic force impact test is tested by an insulation pad evaluation module, and the second performance parameter of the transformer insulation pad to be measured is compared with the first performance parameter to obtain a total comparison result for representing performance change; and the short-circuit electromagnetic force resistance of the transformer insulation pad to be measured is determined according to the total comparison result. The transformer insulation pad is subjected to the simulated short-circuit electromagnetic force impact test, the transformer body is not directly subjected to impact test, the configured short-circuit electromagnetic force impact test condition can simulate the working environment of the transformer insulation pad under normal operation, the transformer insulation pad to be measured is subjected to the simulated short-circuit electromagnetic force impact test through the short-circuit electromagnetic force impact test condition, the first performance parameter and the second performance parameter are compared, the specific change of the performance of the insulation pad after subjected to the short-circuit electromagnetic force impact can be obtained, and thus the short-circuit electromagnetic force resistance of the transformer insulation pad to be measured is determined according to the first comparison result, the requirement on the test condition is not high, the cost of the test is low, and large-scale popularization and application can be carried out.

[0095] It should be noted that the system embodiments described above are only schematic, wherein the units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, that is, they can be located in one place or distributed on a plurality of network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the embodiment. In addition, the connection relationship between the modules in the system embodiment provided by the application indicates that there is a communication connection between them, which can be realized as one or more communication buses or signal lines. Those skilled in the art can understand and implement it without creative labor.

[0096] Those skilled in the art can clearly understand that, for the convenience and brevity, the specific working process of the above-described system can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0097] The above is the preferred embodiment of the present application, it should be pointed out that, for those skilled in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, these improvements and refinements are also considered to be within the scope of the present application.

Claims

1. A method for evaluating the short circuit electromagnetic force impact resistance of a transformer insulation pad, characterized in that, The method comprises the following steps: acquiring a to-be-tested transformer insulating pad and testing a first performance parameter of the to-be-tested transformer insulating pad for representing an initial performance; configuring a short-circuit electromagnetic force impact test condition of the to-be-tested transformer insulating pad; wherein the to-be-tested transformer insulating pad corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval and an electromagnetic impact force number; performing a simulated short-circuit electromagnetic force impact test on the to-be-tested transformer insulating pad according to the short-circuit electromagnetic force impact test condition corresponding to the to-be-tested transformer insulating pad; testing a second performance parameter of the to-be-tested transformer insulating pad after the simulated short-circuit electromagnetic force impact test, and comparing the second performance parameter of the to-be-tested transformer insulating pad with the first performance parameter to obtain a total comparison result for representing a performance change; and determining an anti-short-circuit electromagnetic force capability of the to-be-tested transformer insulating pad according to the total comparison result.

2. The method for evaluating the anti-short circuit electromagnetic force impact of the transformer insulation spacer of claim 1, wherein, In the case that the first performance parameter is a mechanical performance parameter, the determination of the anti-short-circuit electromagnetic force capability of the to-be-tested transformer insulating pad comprises: comparing the first mechanical performance parameter representing the to-be-tested transformer insulating pad before the simulated short-circuit electromagnetic force impact test with the second mechanical performance parameter representing the to-be-tested transformer insulating pad after the simulated short-circuit electromagnetic force impact test to obtain a first comparison result in the total comparison result for representing a mechanical performance change of the to-be-tested transformer insulating pad; and determining the anti-short-circuit capability of the to-be-tested transformer insulating pad according to the first comparison result.

3. The method of claim 1, wherein the transformer insulation spacer is subjected to a short circuit electromagnetic force impact evaluation. In the case that the first performance parameter is an appearance structure parameter, the determination of the anti-short-circuit electromagnetic force capability of the to-be-tested transformer insulating pad comprises: comparing the first appearance structure parameter representing the to-be-tested transformer insulating pad before the simulated short-circuit electromagnetic force impact test with the second appearance structure parameter representing the to-be-tested transformer insulating pad after the simulated short-circuit electromagnetic force impact test to obtain a second comparison result in the total comparison result for representing an appearance structure change of the to-be-tested transformer insulating pad; and determining the anti-short-circuit electromagnetic force capability of the to-be-tested transformer insulating pad according to the second comparison result.

4. The method of claim 2, wherein the transformer insulation spacer is subjected to the short circuit electromagnetic force impact evaluation. The first mechanical performance parameter comprises a first pressure waveform and a first pressure value; and the second mechanical performance parameter comprises a second pressure waveform and a second pressure value. The comparison of the first mechanical performance parameter representing the to-be-tested transformer insulating pad before the simulated short-circuit electromagnetic force impact test with the second mechanical performance parameter representing the to-be-tested transformer insulating pad after the simulated short-circuit electromagnetic force impact test comprises: comparing the second pressure waveform and the second pressure value of the to-be-tested transformer insulating pad after the simulated short-circuit electromagnetic force impact test with the initial first pressure waveform and the first pressure value of the to-be-tested transformer insulating pad, respectively.

5. The method of claim 3, wherein the transformer insulation spacer is subjected to the short circuit electromagnetic force impact evaluation. The first appearance structure parameter comprises a first deformation amount, a first thickness and a first area; and the second appearance structure parameter comprises a second deformation amount, a second thickness and a second area. The comparison of the first appearance structure parameter representing the to-be-tested transformer insulating pad before the simulated short-circuit electromagnetic force impact test with the second appearance structure parameter representing the to-be-tested transformer insulating pad after the simulated short-circuit electromagnetic force impact test comprises: The first deformation variable, the first thickness and the first area of the transformer insulation pad to be tested before the simulated short-circuit electromagnetic force impact test are compared with the second deformation variable, the second thickness and the second area after the simulated short-circuit electromagnetic force impact test.

6. The method of claim 1, wherein the transformer insulation spacer is subjected to the short circuit electromagnetic force impact evaluation. The short-circuit electromagnetic force impact test conditions include: a first test condition for representing a static electromagnetic impact force test, a second test condition for representing a dynamic electromagnetic impact force test, and a third test condition for representing a static electromagnetic impact force test after the dynamic electromagnetic impact force test; The electromagnetic impact force amplitude corresponding to the first test condition is consistent with the electromagnetic impact force amplitude corresponding to the third test condition; The electromagnetic impact force frequency corresponding to the first test condition is consistent with the electromagnetic impact force frequency corresponding to the third test condition.

7. The method of claim 6, wherein the transformer insulation spacer is subjected to a short circuit electromagnetic force impact evaluation. The electromagnetic impact force corresponding to the second test condition presents a periodic change; The calculation of the electromagnetic impact force corresponding to the second test condition includes: The electromagnetic impact force corresponding to the second test condition is calculated according to the electromagnetic impact force amplitude corresponding to the second test condition, a preset electromagnetic impact force frequency and a preset periodic interval.

8. The method of claim 1, wherein, Further comprising: Before the simulated short-circuit electromagnetic force impact test on the transformer insulation pad to be tested, oil immersion treatment is performed.

9. The method of claim 1, wherein the transformer insulation spacer is subjected to a short circuit electromagnetic force impact evaluation. The transformer insulation pad to be tested is composed of a plurality of insulation paper boards with consistent thickness.

10. A transformer insulation pad resistance short-circuit electromagnetic force impact assessment system, characterized in that: Comprising: The pad parameter acquisition module is configured to acquire the transformer insulation pad to be tested and test the first performance parameter of the transformer insulation pad to be tested for representing the initial performance; The condition configuration module is configured to configure the short-circuit electromagnetic force impact test conditions of the transformer insulation pad to be tested; wherein the transformer insulation pad to be tested corresponds to a plurality of short-circuit electromagnetic force impact test conditions; each short-circuit electromagnetic force impact test condition corresponds to an electromagnetic impact force amplitude, an electromagnetic impact force time interval and an electromagnetic impact force frequency; The simulation test module is configured to perform the simulated short-circuit electromagnetic force impact test on the transformer insulation pad to be tested according to the short-circuit electromagnetic force impact test conditions corresponding to the transformer insulation pad to be tested; The insulation pad evaluation module is configured to test the second performance parameter of the transformer insulation pad to be tested after the simulated short-circuit electromagnetic force impact test, compare the second performance parameter of the transformer insulation pad to be tested with the first performance parameter, and obtain the total comparison result for representing the performance change; and determine the short-circuit electromagnetic force resistance of the transformer insulation pad to be tested according to the total comparison result.

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