Earthquake simulation vibration test method and device for transformer equipment

Abstract

The present invention provides a method and apparatus for earthquake simulation vibration testing of transformer equipment. The method comprises: placing a test piece on an earthquake simulation vibration table; arranging measuring instruments on the test piece, and obtaining test measurement values ​​based on the measuring instruments during the test; performing calculations based on the test measurement values ​​to obtain a transformer seismic performance evaluation result corresponding to the test piece; wherein the test piece comprises: a transformer model prefabricated based on the transformer prototype to be tested, or a bushing from the transformer prototype to be tested. The present invention provides a testing method for large transformers that lack earthquake simulation vibration table testing capabilities, providing technical support for seismic performance optimization, seismic design, and seismic evaluation of large transformer equipment.

Description

Technical Field

[0001] The present invention relates to the field of transformer testing, and in particular to an earthquake simulation vibration test method and device for transformer equipment. Background Art

[0002] Earthquake damage surveys show that electrical equipment, especially those made of ceramic materials, is highly vulnerable to damage during earthquakes. Transformers are large and heavy, and their bushings are often made of ceramic. These components are subject to significant seismic forces, which can easily damage the transformer bushings or cause significant displacement of the equipment, leading to loss of electrical function.

[0003] Transformers are core equipment within converter stations, representing large electrical components with a low center of gravity. Under earthquakes, damage to transformers primarily manifests as damage to the bushings attached to the transformer itself, often at the base of the bushings. Bushing-type electrical equipment is inherently vulnerable to seismic damage, and installing them on transformers, where the transformer itself amplifies the bushing's seismic response, further threatens bushing safety. Furthermore, large transformers weigh hundreds of tons, far exceeding the testing capacity of existing earthquake simulation shaker tables. Existing standards lack systematic testing methods for vibration table testing of only the bushings, a vulnerable component in earthquakes. For example, for UHV equipment, there are no technical requirements for bushing installation during testing, resulting in unclear understanding of the transformer's seismic dynamic amplification effect on the bushings. This, in turn, affects the accuracy of transformer seismic performance assessments. Therefore, conducting earthquake simulation shaker tests on large transformers can assess their seismic capacity and level of resistance, providing technical guidance for optimizing and strengthening seismic measures. This has significant practical significance for ensuring the safe and stable operation of substations during earthquakes. Summary of the Invention

[0004] To address the aforementioned deficiencies in the prior art, the present invention provides a method for earthquake simulation vibration testing of transformer equipment. Through dimensional derivation, the present invention proposes design principles for large-scale transformer scale models during earthquake simulation vibration table testing, as well as technical requirements for transformer bushing vibration table testing. This method provides a testing method for large transformers that lack earthquake simulation vibration table testing capabilities, providing technical support for seismic performance optimization, seismic design, and seismic assessment of large transformer equipment.

[0005] The present invention provides a method for earthquake simulation vibration testing of transformer equipment, comprising:

[0006] Place the test piece on an earthquake simulation vibration table;

[0007] Arranging a measuring instrument on the test piece, and obtaining test measurement values ​​based on the measuring instrument during the test process;

[0008] Calculating based on the test measurement value to obtain the transformer seismic performance evaluation result corresponding to the tested piece;

[0009] The tested component includes: a transformer model prefabricated based on the transformer prototype to be tested or a bushing in the transformer prototype to be tested.

[0010] Preferably, the production of the transformer model includes:

[0011] The oil tank shape shall be designed according to the geometric similarity ratio of the transformer prototype, and the thickness of the oil tank bottom plate shall not be less than 20mm. The thickness of the oil tank side wall and top steel plate shall be designed according to the geometric similarity ratio while meeting the strength requirements;

[0012] Use iron blocks or cast iron to simulate the core and windings according to the mass similarity relationship, mass distribution, and center of gravity of the core and windings;

[0013] Each casing model is made according to the geometric similarity ratio with the real casing, and the material and mass similarity ratio of the casing model are the same as those of the actual casing;

[0014] According to the actual transformer oil pillow size and structure, make the transformer model oil pillow according to the geometric similarity ratio;

[0015] Water is used to simulate the transformer oil in the transformer tank.

[0016] Preferably, the production of the transformer model further includes:

[0017] The stress ratio between the fabricated transformer model and the transformer prototype is 1:1.

[0018] Preferably, the transformer model prefabricated based on the transformer prototype to be tested includes:

[0019] When the weight of the transformer prototype to be tested is above 500 tons, the geometric scale ratio of the transformer model to the transformer prototype is 1:3 or 1:4.

[0020] Preferably, placing the tested piece on an earthquake simulation vibration table comprises:

[0021] When the test piece is a bushing in a prototype transformer to be tested:

[0022] installing the casing on an earthquake simulation shaking table; and

[0023] The installation angle of the bushing on the earthquake simulation shaking table is consistent with that of the transformer prototype;

[0024] The natural frequency of the component connecting the bushing and the vibration table test should be greater than 33Hz;

[0025] When the tested component is a transformer model: the transformer model is directly placed on an earthquake simulation vibration table.

[0026] Preferably, placing the casing on an earthquake simulation vibration table further comprises:

[0027] The earthquake input acceleration is multiplied by a factor of 2.0.

[0028] Preferably, the arrangement of a measuring instrument on the tested object includes:

[0029] When the test piece is a bushing in a prototype transformer to be tested:

[0030] Acceleration sensors and displacement sensors are placed on the top of the casing, the connection between the casing and the bracket, and the surface of the earthquake simulation vibration table, and strain gauges are attached to the base of the casing.

[0031] When the tested device is a transformer model:

[0032] Acceleration sensors are placed on the top of each bushing in the transformer model, the connection between the riser and the box, the connection between the bushing and the riser, the four corners of the box, the center of each box side panel, the center of the box cover, and the surface of the earthquake simulation vibration table.

[0033] Strain gauges are evenly distributed along the circumferential direction at the root of each casing;

[0034] Displacement sensors are arranged on the top of each casing, the connection between the casing and the riser, the box cover, and the surface of the earthquake simulation vibration table;

[0035] Wherein, the measuring instrument includes: an acceleration sensor, a displacement sensor and a strain gauge.

[0036] Preferably, when the tested component is a transformer model, the method further includes:

[0037] In the transformer model, acceleration sensors are arranged at the midpoints of each side of the box.

[0038] Preferably, the calculation based on the test measurement value to obtain the transformer seismic performance evaluation result corresponding to the tested component includes:

[0039] Calculate the test response spectrum value at the fundamental frequency point of the test piece during the test based on the acceleration and displacement response of the test piece;

[0040] Calculating the maximum equivalent stress of the test piece under earthquake action based on the maximum equivalent strain at the dangerous section of the test piece measured during the test and the test response spectrum value at the fundamental frequency point of the test piece during the test;

[0041] Calculate the standard value of seismic effect based on the maximum equivalent stress of the tested piece under seismic action;

[0042] Calculate the load effect of the tested component under earthquake conditions based on the standard value of the earthquake effect, the standard value of the wind load effect, the standard value of the deadweight effect of the tested component, the standard value of the internal pressure of the tested component, the actual tension of the conductor and the operating load;

[0043] Calculating the total stress and total bending moment generated by the tested component under the load based on the load effect of the tested component under earthquake conditions;

[0044] The transformer seismic performance evaluation results are obtained based on the relationship between the total stress and total bending moment generated by the test piece under load and the threshold value;

[0045] The test values ​​include: the maximum equivalent strain at the dangerous section of the tested piece, the acceleration and displacement response of the tested piece.

[0046] Preferably, the maximum equivalent stress is calculated as follows:

[0047]

[0048] Where: σ max is the maximum equivalent stress of the tested piece under earthquake action; ε max is the maximum equivalent strain at the dangerous section of the test piece measured during the test; E is the elastic modulus of the test piece; a E is the demand response spectrum value at the fundamental frequency point of the tested piece during the earthquake simulation shaking table test; a EH It is the test response spectrum value at the fundamental frequency point of the test piece during the earthquake simulation shaking table test.

[0049] Preferably, the load effect of the measured component under earthquake conditions is calculated according to the following formula:

[0050] Z E =Z Ge +Z Eh +0.25Z Wk +Z Pk

[0051] Where: Z E is the load effect of the tested component under earthquake conditions; Z Ge is the standard value of the deadweight effect of the tested piece; Z Eh is the standard value of earthquake effect; Z Wk is the standard value of wind load effect; Z Pk It is the standard value of the internal pressure of the tested piece, the actual tension of the wire and the operating load.

[0052] Based on the same inventive concept, the present invention also provides an earthquake simulation vibration test device for transformer equipment, comprising:

[0053] An earthquake simulation vibration table, a test piece placed on the earthquake simulation vibration table, and a measuring instrument arranged on the test piece, wherein the measuring instrument is used to obtain test measurement values ​​during the test;

[0054] The computer externally connected to the earthquake simulation vibration table is used to calculate the seismic performance evaluation result of the transformer corresponding to the tested component based on the test measurement value;

[0055] The tested component includes: a transformer model prefabricated based on the transformer prototype to be tested or a bushing in the transformer prototype to be tested.

[0056] Preferably, the test piece placed on the earthquake simulation vibration table includes:

[0057] When the test piece is a bushing in a prototype transformer to be tested:

[0058] The casing is installed on an earthquake simulation vibration table; and

[0059] The installation angle of the bushing on the earthquake simulation shaking table is consistent with that of the transformer prototype;

[0060] The natural frequency of the component connecting the bushing and the vibration table test should be greater than 33Hz;

[0061] When the tested component is a transformer model: the transformer model is directly placed on an earthquake simulation vibration table.

[0062] Preferably, the casing is placed on an earthquake simulation vibration table, further comprising:

[0063] The earthquake input acceleration is multiplied by a factor of 2.0.

[0064] Compared with the closest existing technology, the technical solution provided by the present invention has the following beneficial effects:

[0065] The technical solution provided by the present invention places a test piece on a seismic simulation vibration table; arranges measuring instruments on the test piece, and obtains test measurement values ​​based on the measuring instruments during the test; performs calculations based on the test measurement values ​​to obtain a transformer seismic performance evaluation result corresponding to the test piece; wherein the test piece includes: a transformer model prefabricated based on the transformer prototype to be tested, or a bushing in the transformer prototype to be tested. The present invention proposes a seismic simulation vibration table test method for transformer models and bushings in transformer prototypes, providing a testing method for large transformers that do not have seismic simulation vibration table testing capabilities, and providing technical support for seismic performance optimization, seismic design, and seismic evaluation of large transformer equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 A flow chart of an earthquake simulation vibration test method for transformer equipment provided by the present invention;

[0067] Figure 2 This is a statistical diagram of the seismic dynamic amplification factor of the ultra-high voltage transformer obtained based on the bushing strain calculation of the present invention. DETAILED DESCRIPTION

[0068] In order to better understand the present invention, the present invention is further described below with reference to the accompanying drawings and examples.

[0069] like Figure 1 As shown, the present invention provides a method for earthquake simulation vibration testing of transformer equipment, comprising:

[0070] S1 places the test piece on an earthquake simulation vibration table;

[0071] S2: arranging a measuring instrument on the test piece, and obtaining a test measurement value based on the measuring instrument during the test;

[0072] S3 performs calculation based on the test measurement value to obtain the transformer seismic performance evaluation result corresponding to the test piece;

[0073] The tested component includes: a transformer model prefabricated based on the transformer prototype to be tested or a bushing in the transformer prototype to be tested.

[0074] The earthquake simulation vibration table test for large transformer equipment provided by the present invention is divided into two parts, one part is the earthquake simulation vibration table test for a large transformer scaled model, and the other part is the earthquake simulation vibration table test for a transformer prototype bushing. The earthquake simulation vibration table test for a large transformer scaled model is a proportional model test for the entire transformer. By testing the equipment model and utilizing the principle of dimensional derivation, the test results can be converted to the prototype structure, thereby evaluating the seismic performance of the prototype structure. Considering that the bushing is the weak part of the transformer structure under earthquake action, for transformer structures with unclear transformer body parameters, the seismic performance of the transformer can be evaluated through the test of the prototype bushing. The earthquake simulation vibration table test for the transformer prototype bushing is a vibration table test solely for the transformer prototype bushing. During the test, the seismic dynamic amplification effect of the transformer box on the bushing is taken into account. The seismic performance of the transformer is directly evaluated through the vibration table test of the prototype bushing.

[0075] (1) Large transformer scale model earthquake simulation vibration table test

[0076] According to Buckingham π theorem, the seismic response of a structure can be expressed as the following functional relationship within the linear elastic range:

[0077] σ=f(l,E,ρ,t,r,v,a,g,ω)

[0078] Where σ is the structural reaction stress, l is the component size, E is the component elastic modulus, ρ is the component density, t is time, r is displacement, v is velocity, a is acceleration, g is the acceleration of gravity, and ω is frequency. Taking l, E, and ρ as the basic quantities, the remaining quantities can be expressed as power monomials of l, E, and ρ, and the dimensionless product π can be obtained:

[0079] Π0=σ / E

[0080] Π1=l / l

[0081] Π2=E / E

[0082] Π3=ρ / ρ

[0083] Π4=t / (lE -0.5 ρ 0.5 )

[0084] Π5=r / l

[0085] Π6=v / (E 0.5 ρ -0.5 )

[0086] Π7=a / (l -1 Eρ -1 )

[0087] Π8=g / (l-1 Eρ -1 )

[0088] Π9=ω / (l -1 E 0.5 ρ -0.5 )

[0089] Define S n is the similarity ratio of the physical quantity (n) between the model and the prototype. In order for the model test to simulate the seismic response of the prototype structure, the similarity ratio of each quantity needs to meet the following requirements:

[0090] S σ =S E , S r =S l ,

[0091] in The subscript m represents a model, and p represents a prototype.

[0092] Since the gravitational acceleration in the experiment cannot be changed, we have Right now Lead to S E 、S l 、S ρ It cannot be chosen arbitrarily and independently. To solve this problem, there are currently three main similarity models:

[0093] 1) Ignore the gravity model: Ignore the simulation of gravity acceleration, that is, ignore S g =1 similarity requirement, then S E 、S l 、S ρ Still able to make independent arbitrarily choices.

[0094] 2) Artificial quality model: Based on S E =S l S ρ , we can get Among them S m is the ratio of the model mass to the prototype mass.

[0095] 3) Under-artificial mass model: sacrifices part of the simulation of gravity acceleration, that is, only ensures The specific value depends on the application of counterweight.

[0096] For large transformer structures, using artificial mass models and under-artificial mass models requires adding counterweights to the transformer model structure. However, since the cross-sectional dimensions of the load-bearing components decrease after the model is scaled down, the bearing capacity is reduced, which increases the difficulty of conducting tests on the scaled model. Considering the performance of the shaking table, the difficulty of test implementation, and model fabrication, it is recommended to use a gravity-neglecting model for earthquake simulation shaking table tests on large transformer structures. The materials of the model components are the same as those of the prototype, only the dimensions are reduced. For transformers with a prototype weight of 500 tons or more, a geometric scale ratio of 1:3 or 1:4 is recommended for the model. The similarity relationships between the physical quantities in the model are shown in Table 1.

[0097] Table 1 Similarity relations of various physical quantities

[0098]

[0099] The design principles and related requirements for each component of the transformer model in the earthquake simulation shaking table test of the large transformer scale model are as follows:

[0100] Fuel tank design: The fuel tank shape is designed according to the geometric similarity ratio of the prototype. Considering that the bottom of the fuel tank is connected to the table top of the earthquake simulation vibration table, the fuel tank bottom plate is appropriately thickened and the thickness can be designed to be no less than 20mm. The thickness of the fuel tank side wall and top steel plate is designed according to the geometric similarity ratio while meeting the strength requirements.

[0101] Core and Winding Design: The core is a closed magnetic circuit composed of stacked silicon steel sheets with excellent magnetic conductivity, serving as the magnetic path for electromagnetic induction in the transformer. In addition to the core itself (the magnetic conductor), the core also includes fastening, insulation, grounding, heat dissipation, and other core accessories. Windings are the circuit components of the transformer and are generally divided into high- and low-voltage windings, or primary and secondary windings. They consist of multi-layer coils of insulated copper or aluminum wire wrapped around the core. Because the core and windings are located inside the oil tank and immersed in transformer oil, they are less susceptible to structural damage from external forces when mounted in good conditions. Therefore, during model design, the core and windings were simulated using iron blocks or cast iron, based solely on mass similarity, mass distribution, and center of gravity of the core and windings.

[0102] Casing design: Each casing model is made according to the geometric similarity ratio with the real casing. It should be ensured that the material of the casing model is the same as that of the actual casing, and the mass similarity ratio remains unchanged.

[0103] Oil pillow design: Made according to the actual transformer oil pillow size and structural form and in accordance with the geometric similarity ratio.

[0104] Transformer Oil Simulation: Water was chosen to simulate the transformer oil in the tank because its density is similar to that of transformer oil and it is readily available. Although the viscosity of the two differs significantly, in actual operation, the transformer oil typically fills the entire transformer tank, minimizing sloshing effects. Therefore, differences in liquid viscosity have little impact on the test results.

[0105] (2) Earthquake simulation vibration table test of transformer prototype bushing

[0106] 1) Value of the earthquake dynamic amplification factor of the transformer body

[0107] For large transformers that do not use scaled models in vibration table tests, vibration table tests on prototype bushings can be used to directly evaluate the transformer's seismic performance. During the test, the transformer's main body's seismic dynamic amplification effect on the bushing is considered. The China Electric Power Research Institute Co., Ltd., through research on the seismic response of transformer equipment, found that since seismic waves change their spectral characteristics after being transmitted from the transformer body to the bushing, using the bushing's acceleration response as the basis for calculating the transformer's dynamic amplification factor is inappropriate. However, the peak stress response is often an important indicator for evaluating the intensity of the bushing's seismic response and is also an important basis for determining whether the transformer structure has been damaged or destroyed. Therefore, it is more reasonable to use the stress response as the basis for evaluating the seismic dynamic amplification factor.

[0108] Figure 2 This is a statistical chart of the seismic dynamic amplification factor of a UHV transformer, calculated based on bushing strain. The calculation method is: the ratio of the peak strain response of each strain gauge on the transformer bushing to the peak strain response of a single bushing under the same earthquake conditions. The statistical data in the figure shows that the maximum seismic dynamic amplification factor of the transformer body on the bushing is 1.87. When the stiffness of the UHV transformer body, the dynamic characteristics of the bushing, and the connection method between the body and the bushing vary, the seismic dynamic amplification factor is always less than 2.0. Therefore, a seismic dynamic amplification factor of 2.0 generally encompasses the effects of changes in the stiffness of the UHV transformer body, the dynamic characteristics of the bushing, and the connection method between the body and the bushing on the seismic dynamic amplification of the bushing.

[0109] In summary, the seismic dynamic amplification effect of the transformer body should be calculated based on the stress response. The seismic dynamic amplification factor for the UHV transformer body is defined as the ratio of the peak stress response when the transformer bushing is installed in the body to the peak stress response when the bushing is installed on a rigid support, under the same earthquake action. Based on simulation and test results, a seismic dynamic amplification factor of 2.0 is recommended for the UHV transformer body.

[0110] 2) Requirements for transformer prototype bushing seismic simulation vibration table test:

[0111] a) During the test, the installation angle of the transformer bushing is consistent with the installation angle of the bushing on the transformer box.

[0112] b) The component connecting the casing and the vibration table test should have sufficient rigidity. When the bottom end is fixed, its natural frequency should be greater than 33 Hz to ensure that the seismic waves transmitted to the casing have consistent spectral characteristics with the seismic waves on the vibration table surface.

[0113] c) Considering the earthquake dynamic amplification effect of the transformer body 2.0, multiply the earthquake input acceleration by a coefficient of 2.0.

[0114] (3) Principles of measuring point arrangement during earthquake simulation shaking table test

[0115] The measuring instruments used in the test are accelerometers, displacement sensors and strain gauges. The layout principles and instructions for each type of measuring point are as follows:

[0116] 1) The number and location of acceleration measurement points should be sufficient to reflect the dynamic performance of the transformer and the test bushing. To measure the acceleration response of each bushing, an acceleration sensor is placed at the top of each bushing of the transformer. To obtain the seismic dynamic amplification effect of the transformer body, acceleration sensors are placed at the connection between the riser and the box, and at the connection between the riser and the bushing. To obtain the dynamic response of the oil tank, acceleration sensors are placed at the four top corners of the transformer box, the center of each box side panel, the center of the box cover, and the vibration table surface. In addition, if the number of channels is sufficient, acceleration sensors are also placed at the midpoint of each side of the box to obtain a more detailed and comprehensive dynamic response of the transformer box.

[0117] 2) According to calculations and previous engineering experience, the maximum stress of the casing occurs at the root of the casing. Therefore, strain gauges are evenly distributed along the circumference of the root of the casing. The maximum stress at the root of the casing is calculated by measuring the maximum strain at the root of the casing.

[0118] 3) To measure the displacement response at the top of each bushing, a displacement meter was placed on top of each bushing. To measure the relative displacement response of the bushings, a displacement meter was placed at the connection between the bushing and the riser. A displacement meter was placed at a suitable location on the cover to measure the displacement response at the top of the transformer case. A displacement meter was placed on the vibration table to measure the displacement response of the table.

[0119] 4) For the earthquake simulation shaking table test of the casing prototype, accelerometers and displacement meters were placed at the top of the casing, at the connection between the casing and the bracket, and on the shaking table surface to measure the acceleration and displacement response of the casing and bracket, as well as the acceleration and displacement time history output from the shaking table surface. Strain gauges were attached to the base of the casing to measure the strain response of the casing.

[0120] The test values ​​measured by arranging measuring instruments include: strain response at the bushing root, acceleration and displacement response at the bushing top, acceleration and displacement response at the top of the transformer body and the top of the riser.

[0121] (4) Seismic performance assessment

[0122] Maximum equivalent stress σ of equipment under earthquake max According to the maximum equivalent strain ε at the dangerous section of the equipment measured during the test max The elastic modulus of the equipment is calculated as follows:

[0123]

[0124] Where: a E is the demand response spectrum (RRS) value at the fundamental frequency point of the equipment during the earthquake simulation shaking table test; a EH It is the test response spectrum (TRS) value at the fundamental frequency point of the equipment during the earthquake simulation shaking table test.

[0125] When evaluating the mechanical properties of electrical equipment, the combination of different loads should be considered. The combination of seismic effects and other load effects of electrical equipment should be calculated according to the following formula:

[0126] Z E =Z Ge +Z Eh +0.25Z Wk +Z Pk

[0127] Where: Z E is the standard value combination of load effects under earthquake conditions; Z Ge is the standard value of the equipment’s deadweight effect; Z Eh is the standard value of earthquake effect; Z Wk The standard value of wind load effect is: UHV equipment is based on the design wind speed of 100 years at the location where the equipment is used; other voltage level electrical equipment is based on the design wind speed of 50 years at the location where the equipment is used; Z Pk The standard value of the internal pressure of the equipment, the actual tension of the wire and the operating load, etc.

[0128] The mechanical performance evaluation and verification of electrical equipment should ensure that the stress value generated at the root of the equipment or other dangerous sections is less than the allowable stress value of the equipment or material. When using the failure stress or failure bending moment for verification, the casing stress and bending moment should meet the requirements of the following formulas respectively:

[0129] The total stress of the bushing and insulator caused by the load should be calculated according to the following formula:

[0130]

[0131] Where: σ tot is the total stress generated by the load combination (Pa); σ v is the destructive stress value of the equipment or material (Pa); k is the safety factor of the equipment under load, which is 2.5 under long-term loads such as strong winds; under short-term loads such as earthquakes, it is 1.67 for porcelain electrical equipment.

[0132] The total bending moment of the porcelain bushing and porcelain insulator caused by the load should be calculated according to the following formula:

[0133]

[0134] Where: M tot is the total bending moment generated by the load combination (N·m); M v is the breaking bending moment of the equipment or material (N·m).

[0135] This invention provides two parallel seismic tests for transformer prototype bushings and transformer models, allowing for flexible selection based on practical circumstances and the advantages and disadvantages of each test method. Because bushings are a vulnerable part of the transformer structure under earthquakes, the seismic performance of transformers with unclear transformer parameters can be assessed through prototype bushing testing, taking into account the transformer's seismic dynamic amplification factor.

[0136] The present invention has made the following contributions relative to the prior art:

[0137] 1. Design principles of oil tank, core winding, bushing and oil pillow in earthquake simulation shaking table test of large transformer scale model, and simulation method of transformer oil.

[0138] 2. The component connecting the casing and the vibration table test should have sufficient rigidity. When the bottom end is fixed, its natural frequency should be greater than 33Hz to ensure that the seismic waves transmitted to the casing and the seismic waves on the vibration table surface have consistent spectral characteristics.

[0139] 3. The earthquake dynamic amplification effect of the transformer body is calculated based on the stress response. When the seismic performance of the transformer bushing is evaluated through the earthquake simulation shaking table test of the transformer prototype bushing, the earthquake dynamic amplification coefficient of the transformer body is taken as 2.0.

[0140] Example 2

[0141] Based on the same inventive concept, the present invention also provides an earthquake simulation vibration test device for transformer equipment, comprising:

[0142] An earthquake simulation vibration table, a test piece placed on the earthquake simulation vibration table, and a measuring instrument arranged on the test piece, wherein the measuring instrument is used to obtain test measurement values ​​during the test;

[0143] The computer externally connected to the earthquake simulation vibration table is used to calculate the seismic performance evaluation result of the transformer corresponding to the tested component based on the test measurement value;

[0144] The tested component includes: a transformer model prefabricated based on the transformer prototype to be tested or a bushing in the transformer prototype to be tested.

[0145] In an embodiment, the test piece placed on the earthquake simulation vibration table includes:

[0146] When the test piece is a bushing in a prototype transformer to be tested:

[0147] The casing is installed on an earthquake simulation vibration table; and

[0148] The installation angle of the bushing on the earthquake simulation shaking table is consistent with that of the transformer prototype;

[0149] The natural frequency of the component connecting the bushing and the vibration table test should be greater than 33Hz;

[0150] When the tested component is a transformer model: the transformer model is directly placed on an earthquake simulation vibration table.

[0151] Furthermore, the casing is placed on an earthquake simulation vibration table, and further comprises:

[0152] The earthquake input acceleration is multiplied by a factor of 2.0.

[0153] In an embodiment, the computing device is specifically configured to:

[0154] Calculate the test response spectrum value at the fundamental frequency point of the test piece during the test based on the acceleration and displacement response of the test piece;

[0155] Calculating the maximum equivalent stress of the test piece under earthquake action based on the maximum equivalent strain at the dangerous section of the test piece measured during the test and the test response spectrum value at the fundamental frequency point of the test piece during the test;

[0156] Calculate the standard value of seismic effect based on the maximum equivalent stress of the tested piece under seismic action;

[0157] Calculate the load effect of the tested component under earthquake conditions based on the standard value of the earthquake effect, the standard value of the wind load effect, the standard value of the deadweight effect of the tested component, the standard value of the internal pressure of the tested component, the actual tension of the conductor and the operating load;

[0158] Calculating the total stress and total bending moment generated by the tested component under the load based on the load effect of the tested component under earthquake conditions;

[0159] The transformer seismic performance evaluation results are obtained based on the relationship between the total stress and total bending moment generated by the test piece under load and the threshold value;

[0160] The test values ​​include: the maximum equivalent strain at the dangerous section of the tested piece, the acceleration and displacement response of the tested piece.

[0161] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0162] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0163] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0164] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0165] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A method for earthquake simulation vibration testing of transformer equipment, characterized in that: include: Place the test piece on an earthquake simulation vibration table; Arranging a measuring instrument on the test piece, and obtaining test measurement values ​​based on the measuring instrument during the test process; Calculating based on the test measurement value to obtain the transformer seismic performance evaluation result corresponding to the tested piece; The tested piece includes: a transformer model prefabricated based on the transformer prototype to be tested or a bushing in the transformer prototype to be tested; The production of the transformer model includes: The oil tank shape shall be designed according to the geometric similarity ratio of the transformer prototype, and the thickness of the oil tank bottom plate shall not be less than 20mm. The thickness of the oil tank side wall and top steel plate shall be designed according to the geometric similarity ratio while meeting the strength requirements; Use iron blocks or cast iron to simulate the core and windings according to the mass similarity relationship, mass distribution, and center of gravity of the core and windings; Each casing model is made according to the geometric similarity ratio with the real casing, and the material and mass similarity ratio of the casing model are the same as those of the actual casing; According to the actual transformer oil pillow size and structure, make the transformer model oil pillow according to the geometric similarity ratio; Water is used to simulate the transformer oil in the transformer tank; The production of the transformer model also includes: The stress ratio between the fabricated transformer model and the transformer prototype is 1:1; The calculation based on the test measurement value to obtain the transformer seismic performance evaluation result corresponding to the tested component includes: Calculate the test response spectrum value at the fundamental frequency point of the test piece during the test based on the acceleration and displacement response of the test piece; Calculating the maximum equivalent stress of the test piece under earthquake action based on the maximum equivalent strain at the dangerous section of the test piece measured during the test and the test response spectrum value at the fundamental frequency point of the test piece during the test; Calculate the standard value of seismic effect based on the maximum equivalent stress of the tested piece under seismic action; Calculate the load effect of the tested component under earthquake conditions based on the standard value of the earthquake effect, the standard value of the wind load effect, the standard value of the deadweight effect of the tested component, the standard value of the internal pressure of the tested component, the actual tension of the conductor and the operating load; Calculating the total stress and total bending moment generated by the tested component under the load based on the load effect of the tested component under earthquake conditions; The transformer seismic performance evaluation results are obtained based on the relationship between the total stress and total bending moment generated by the test piece under load and the threshold value; The test values ​​include: the maximum equivalent strain at the dangerous section of the tested piece, the acceleration and displacement response of the tested piece; At present, the following three similarity models are mainly used to calculate the similarity ratio of component elastic modulus S E , component size similarity ratio S l , component density similarity ratio S ρ Choices: 1) Ignore the gravity model: Ignore the simulation of gravity acceleration, that is, ignore the gravity acceleration similarity ratio S g =1 similarity requirement, then S E 、S l 、S ρ Still able to make arbitrary choices independently; 2) Artificial quality model: Based on S E =S l S ρ , we can get Among them S m is the ratio of the model mass to the prototype mass; 3) Under-artificial mass model: sacrifices part of the simulation of gravity acceleration, that is, only ensures The specific value depends on the application of counterweight.

2. The method according to claim 1, wherein The transformer model prefabricated based on the transformer prototype to be tested includes: When the weight of the transformer prototype to be tested is above 500 tons, the geometric scale ratio of the transformer model to the transformer prototype is 1:3 or 1:

4.

3. The method according to claim 1, wherein Placing the test piece on the earthquake simulation vibration table includes: When the test piece is a bushing in a prototype transformer to be tested: installing the casing on an earthquake simulation shaking table; and The installation angle of the bushing on the earthquake simulation shaking table is consistent with that of the transformer prototype; The natural frequency of the component connecting the bushing and the vibration table test should be greater than 33Hz; When the tested component is a transformer model: the transformer model is directly placed on an earthquake simulation vibration table.

4. The method according to claim 3, wherein Placing the casing on an earthquake simulation vibration table further comprises: The earthquake input acceleration is multiplied by a factor of 2.

0.

5. The method according to claim 1, wherein The step of arranging a measuring instrument on the tested object includes: When the test piece is a bushing in a prototype transformer to be tested: Acceleration sensors and displacement sensors are placed on the top of the casing, the connection between the casing and the bracket, and the surface of the earthquake simulation vibration table, and strain gauges are attached to the base of the casing. When the tested device is a transformer model: Acceleration sensors are placed on the top of each bushing in the transformer model, the connection between the riser and the box, the connection between the bushing and the riser, the four corners of the box, the center of each box side panel, the center of the box cover, and the surface of the earthquake simulation vibration table. Strain gauges are evenly distributed along the circumferential direction at the root of each casing; Displacement sensors are arranged on the top of each casing, the connection between the casing and the riser, the box cover, and the surface of the earthquake simulation vibration table; Wherein, the measuring instrument includes: an acceleration sensor, a displacement sensor and a strain gauge.

6. The method according to claim 5, wherein When the tested device is a transformer model, the method further includes: In the transformer model, acceleration sensors are arranged at the midpoints of each side of the box.

7. The method according to claim 1, wherein The maximum equivalent stress is calculated according to the following formula: Where: σ max is the maximum equivalent stress of the tested piece under earthquake action; ε max is the maximum equivalent strain at the dangerous section of the test piece measured during the test; E is the elastic modulus of the test piece; a E is the demand response spectrum value at the fundamental frequency point of the tested piece during the earthquake simulation shaking table test; a EH It is the test response spectrum value at the fundamental frequency point of the test piece during the earthquake simulation shaking table test.

8. The method according to claim 1, wherein The load effect of the tested component under earthquake conditions is calculated as follows: WITH E =Z Ge +Z Eh +0.25Z Wk +Z Pk Where: Z E is the load effect of the tested component under earthquake conditions; Z Ge is the standard value of the deadweight effect of the tested piece; Z Eh is the standard value of earthquake effect; Z Wk is the standard value of wind load effect; Z Pk It is the standard value of the internal pressure of the tested piece, the actual tension of the wire and the operating load.

Images