Transformer used in seismic zone tunnel and anti-seismic simulation method thereof

Abstract

The invention discloses a transformer used in a seismic zone tunnel and an anti-seismic simulation method thereof, and belongs to the technical field of transformer simulation detection, and the method comprises the following steps: building a transformer structure simulation model; performing static analysis to obtain the maximum stress of the transformer; the first-order vibration frequency of the transformer is obtained through modal analysis, and the first-order vibration frequency of the transformer is used for representing the lowest frequency vibration characteristic generated by the structure of the transformer due to the material attribute when the transformer has no external excitation; performing response spectrum analysis to obtain equivalent stress distribution and an equivalent stress value of the transformer under the simulated seismic load; performing fatigue analysis based on the equivalent stress value of the transformer, and estimating the fatigue strength of the transformer structure; according to the scheme, the transformer can be arranged in a split mode in a seismic zone tunnel, the anti-seismic performance of the transformer in an earthquake can be evaluated, and the structural safety of the transformer is verified by simulating the seismic load waveform and the vibration response.

Description

Technical Field

[0001] This invention relates to the field of transformer simulation and testing technology, and more specifically, to a transformer used in tunnels in earthquake zones and its seismic simulation method. Background Technology

[0002] With the continuous advancement of national infrastructure construction, tunnel projects in earthquake zones are increasing, which places higher demands on the safety and stability of the power system. As the core equipment for power transmission and distribution, the rational design of transformers in tunnels is directly related to the safe operation of tunnel projects and the power supply capability in emergency situations.

[0003] Inside tunnels, especially in seismic zones, the height of rectifier transformers is subject to strict requirements. Transformers in such compact spaces often employ split-type technology, using two or more transformers of the same capacity and group in parallel to meet the stringent size requirements. However, seismic zones also place extremely stringent requirements on the seismic resistance of transformers. The limited space and complex electromagnetic environment of tunnels pose significant challenges to the electromagnetic and structural design of rectifier transformers.

[0004] Statistics from major earthquakes both domestically and internationally show that transformers suffer severe damage in high-intensity earthquake zones because their natural frequency is close to that of seismic waves. This damage not only causes direct economic losses but also leads to serious secondary disasters. Due to the large size of rectifier transformers and the fact that existing numerical models have simplified the original structure considerably, it is difficult to conduct shaking table tests on the prototype transformer structure under current conditions. Summary of the Invention

[0005] The purpose of this invention is to solve the technical problem that existing technologies have difficulty in identifying and locating stress concentration areas in transformer structures, and to propose a transformer and its seismic simulation method for use in tunnels in earthquake zones.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of this application provides a transformer seismic simulation method, including the following steps: Establish a transformer structure simulation model; Static analysis is used to determine the maximum stress in a transformer. Modal analysis is used to obtain the first-order vibration frequency of the transformer. The first-order vibration frequency of the transformer is used to characterize the lowest frequency vibration characteristics of the transformer structure due to material properties when there is no external excitation. Response spectrum analysis is used to obtain the equivalent stress distribution of the transformer under simulated seismic load and the maximum stress obtained from the response spectrum analysis. Fatigue analysis is performed based on the maximum stress of the transformer response spectrum to predict the fatigue strength of the transformer structure.

[0007] Furthermore, the static analysis is performed by assessing the strength using the inertial forces corresponding to the accelerations on the X, Y, and Z axes respectively; the acceleration on the X-axis is taken as 1g, the acceleration on the Y-axis is taken as 3g, and the acceleration on the Z-axis is taken as 1g, where g is the acceleration due to gravity.

[0008] Furthermore, during the response spectrum analysis, loads are applied to the X, Y, and Z axes respectively, with a single-condition loading time of 30 minutes and a loading time of 12 hours per axis; the acceleration proportionality coefficients of the X, Y, and Z axes are calculated and obtained respectively; based on the acceleration proportionality coefficients of the X, Y, and Z axes, the maximum stress of the response spectrum analysis of the X, Y, and Z axes is calculated and obtained respectively.

[0009] Furthermore, the fatigue analysis based on the maximum stress of the transformer response spectrum includes the following steps: Based on the maximum stress analyzed by response spectrum, and according to Miner's linear fatigue cumulative damage calculation formula, the damage of the transformer in the X, Y, and Z axis directions is calculated respectively.

[0010] Furthermore, the Miner linear fatigue cumulative damage calculation formula is as follows: , In the formula: D is the damage value; N f ∆ is the number of load cycles; The stress range is given; the typical value of the exponent m is 3 to 9; α is a constant.

[0011] Furthermore, in the step of calculating the acceleration proportionality coefficients for the X, Y, and Z axes respectively, the formula for calculating the acceleration proportionality coefficient is: , In the formula: ∆ is the acceleration proportionality coefficient; t Minimum stress range; ∆ s The maximum stress range; α1 and α2 are both constants; N t N is the minimum load cycle number; s The maximum load cycle number; typical values ​​for the exponents m1 and m2 are 3 to 9.

[0012] Another aspect of this application provides a transformer for use in earthquake zone tunnels, the transformer for use in earthquake zone tunnels comprising: Base; An iron core is located above the base; the iron core includes: a plurality of iron core columns and an upper iron yoke and a lower iron yoke located at both ends of the iron core columns respectively; A core clamping component, comprising an upper clamping component and a lower clamping component, wherein the upper clamping component clamps the upper yoke, and the lower clamping component is connected to the base and clamps the lower yoke, thereby fixing the core to the base; A winding, disposed between the upper clamp and the lower clamp, comprising: A plurality of low-voltage coils, wherein the low-voltage coils are epoxy resin foil windings, and the plurality of the low-voltage coils are respectively sleeved on the outside of the iron core column; A plurality of high-voltage coils, wherein the high-voltage coils are epoxy resin wire-wound coils, and the plurality of high-voltage coils are respectively sleeved on the outside of the low-voltage coil; An insulating cylinder is disposed between the low-voltage coil and the high-voltage coil; Insulating pads, a plurality of the insulating pads are respectively disposed between the winding and the iron core clamp, for pressing and fixing the winding.

[0013] Furthermore, the lower clamp includes: A first clamping plate is fixed to the base. The second clamping plate is fixed to the base and is parallel to the first clamping plate; A tensioning screw passes through the first clamping plate and the second clamping plate, and bolts are respectively provided at both ends of the tensioning screw; A clamping insulating plate is disposed on the inner side of the first clamping plate, the inner side of the second clamping plate, and the surface of the base; A core pad is disposed inside the insulating plate of the clamp, and the core pad is adapted to the shape of the lower yoke surface.

[0014] Furthermore, a double-layer insulating cylinder is provided between the low-voltage coil and the high-voltage coil, and gaps for insulation and heat dissipation are left between the insulating cylinder and the low-voltage coil, between the insulating cylinders themselves, and between the insulating cylinder and the high-voltage coil.

[0015] Furthermore, a phase spacer is provided between the high-voltage coils, and the two ends of the phase spacer are respectively fixed to the upper clamp and the lower clamp.

[0016] The beneficial effects of this invention are as follows: The transformer provided in this application for use in tunnels in earthquake zones uses epoxy resin casting to form low-voltage and high-voltage coils, which can withstand the electrodynamic forces generated during short circuits, ensuring safe and reliable operation in earthquake zones without causing environmental pollution; the use of phase spacers and insulating cylinders reduces the space occupied by the transformer while ensuring the insulation performance of the windings; and the use of automatically controlled cooling fans optimizes the air intake angle of the transformer, improving the heat dissipation effect and reliability of the transformer.

[0017] The technical solution adopted in this application is conducive to the separate installation of transformers in tunnels in earthquake zones. By making reasonable use of space and flexibly arranging the layout, it can reduce voltage fluctuations, improve voltage stability, and improve power quality. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of a transformer used in a tunnel in an earthquake zone, provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of the core structure in an embodiment of the present invention; Figure 3 This is a schematic diagram of the lower clamping component structure in an embodiment of the present invention; Figure 4 This is a schematic diagram of the winding structure in an embodiment of the present invention; Figure 5 This is a schematic diagram of the finite element mechanical model for transformer structure simulation in an embodiment of the present invention.

[0019] The markings in the diagram are as follows: 1. Base; 11. Frame channel steel; 12. Side length channel steel; 13. Reinforcing rib plate; 2. Iron core; 21. Iron core post; 22. Upper yoke; 23. Lower yoke; 3. Iron core clamp; 31. Upper clamp; 32. Lower clamp; 321. First clamping plate; 322. Second clamping plate; 323. Tensioning screw; 324. Clamping insulation plate; 325. Iron core pad; 4. Winding; 41. Low-voltage coil; 411. Silicone round bar; 412. Zero-point copper busbar; 413. Low-voltage copper busbar; 42. High-voltage coil; 421. Phase spacer; 43. Insulating cylinder; 5. Insulating pads; 6. Cooling fan. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0024] Please see Figures 1 to 4 The illustrated embodiment of this application provides a transformer for use in tunnels in earthquake zones. In practical applications, the transformer used in tunnels in earthquake zones performs voltage conversion in the traction power supply and auxiliary power supply links, providing stable and efficient power support for the traction power supply and station equipment of rail transit systems such as subways and high-speed railways. The transformer used in tunnels in earthquake zones includes: a base 1, an iron core 2, an iron core clamp 3, a winding 4, and an insulating pad 5.

[0025] In this embodiment, the base 1 supports the upper structure and includes four skeleton channel steels 11 and several side-length channel steels 12. The skeleton channel steels 11 are arranged in pairs in parallel, and the two skeleton channel steels 11 in the same group are connected by reinforcing ribs 13. The side-length channel steels 12 are connected between the two groups of skeleton channel steels 11. The side-length channel steels 12 increase the contact area between the base 1 and the ground, thereby distributing the load and improving the load-bearing capacity and seismic performance of the base 1.

[0026] Iron core 2, as the core magnetic circuit component of the transformer, functions to conduct magnetism, form a closed magnetic circuit, and reduce magnetic reluctance; please refer to [link / reference needed]. Figure 2In this embodiment, the core 2 is composed of several cold-rolled silicon steel sheets with oblique joints stacked together. The core 2 is located above the base 1 and includes three core columns 21, an upper yoke 22, and a lower yoke 23. The upper yoke 22 and the lower yoke 23 are both D-shaped yokes and are located at the upper and lower ends of the core columns 21, respectively. With the above technical solution, the core columns 21 are tied with cable ties, and the cold-rolled silicon steel sheets with oblique joints can effectively reduce the no-load loss during transformer operation.

[0027] The core clamp 3 includes an upper clamp 31 and a lower clamp 32; the upper clamp 31 clamps the upper yoke 22, and the lower clamp 32 is connected to the frame channel steel 11 and clamps the lower yoke 23, thus fixing the core 2 to the base 1; for details, please refer to [link to details]. Figure 3 The lower clamp 32 includes: a first clamping plate 321, a second clamping plate 322, a tensioning screw 323, a clamping insulating plate 324, and a core pad 325; the first clamping plate 321 and the second clamping plate 322 are both fixed to the frame channel steel 11 and are parallel to each other; the tensioning screw 323 passes through the first clamping plate 321 and the second clamping plate 322, and bolts are respectively provided at both ends of the tensioning screw 323, and the first clamping plate 321 and the second clamping plate 322 are brought closer to the core 2 by tightening the bolts; the clamping insulating plate 324 is provided on the inner side of the first clamping plate 321, the inner side of the second clamping plate 322, and the frame. On the upper surface of the channel steel 11, the clamping insulation plate 324 serves two purposes: firstly, it supports and fixes the iron core 2; secondly, it isolates the iron core 2 from the first clamping plate 321 and the second clamping plate 322, preventing short circuits or leakage and improving transformer safety. The iron core pad 325 is disposed inside the clamping insulation plate 324. As a component in direct contact with the iron core 2, in this embodiment, the iron core pad 325 is shaped to match the surface of the lower yoke 23, ensuring a tight fit and stable clamping of the iron core 2 when they come into contact. It is understood that the upper clamping member 31 clamps the upper yoke 22 in the same manner as the lower clamping member 32.

[0028] Please see Figure 4The winding 4 plays a core role in the transformer in transmitting current, transforming voltage, and transferring electrical energy. It is located between the upper clamp 31 and the lower clamp 32 and includes a low-voltage coil 41, a high-voltage coil 42, and an insulating cylinder 43. The low-voltage coil 41 is an epoxy resin foil winding, and three sets of low-voltage coils 41 are respectively sleeved on the outside of three iron core columns 21. Multiple silicone round rods 411 are arranged in the gap between the low-voltage coil 41 and the iron core column 21. The silicone round rods 411 release elastic force to press the low-voltage coil 41 and the iron core column 21 together, so that the relative positions between any two are fixed. A zero-point copper busbar 412 is installed above the low-voltage coil 41. The end of the zero-point copper busbar 412 away from the low-voltage coil 41 is connected to power distribution equipment such as a power receiving cabinet or power distribution cabinet. The zero-point copper busbar 412 is used to ensure the stability of high current transmission and avoid local overheating or insulation breakdown of the transformer. A low-voltage copper busbar 413 is installed below the low-voltage coil 41. The end of the low-voltage copper busbar 413 away from the low-voltage coil 41 is connected to the power distribution equipment. The low-voltage copper busbar 413 is used to efficiently transmit the high current on the low-voltage side of the transformer and reduce power loss. The zero-point copper busbar 412 and the low-voltage copper busbar 413 are connected by a tail copper busbar. The tail copper busbar is close to the inside of the low-voltage coil 41. An insulating pull plate is installed between the tail copper busbar and the iron core column 21. The insulating pull plate maintains a sufficient insulation distance between the tail copper busbar and the iron core column 21 to avoid the risk of short circuit or discharge caused by electromagnetic induction or electrostatic induction. The high-voltage coil 42 is an epoxy resin wire-wound winding, and the three sets of high-voltage coils 42 are respectively wound around the outside of the three sets of low-voltage coils 41. This low-voltage foil-type and high-voltage wire-wound winding configuration effectively reduces electrical density, thereby reducing resistance loss and minimizing transformer size. Both the low-voltage coils 41 and the high-voltage coils 42 are cast with epoxy resin, ensuring the overall structural strength of the coils. Furthermore, epoxy resin does not contain harmful substances and will not endanger human health.

[0029] An insulating cylinder 43 is disposed in the gap between the low-voltage coil 41 and the high-voltage coil 42. The insulating cylinder 43 is used to improve the electric field distribution, which reduces the air insulation distance between the high-voltage and low-voltage coils of the transformer and ensures the insulation reliability of the transformer. As a preferred embodiment of this application, a double-layer insulating cylinder 43 is disposed between the low-voltage coil 41 and the high-voltage coil 42. Gaps are left between the insulating cylinder 43 and the low-voltage coil 41, between the insulating cylinders 43, and between the insulating cylinder 43 and the high-voltage coil 42 as insulation and heat dissipation channels.

[0030] Several insulating pads 5 are respectively disposed between the winding 4 and the iron core clamp 3; specifically, the upper clamp 31 and the lower clamp 32 are provided with pad brackets, and the insulating pads 5 are provided with slots that are adapted to the shape of the edge of the low voltage coil 41, the edge of the high voltage coil 42 and the edge of the insulating cylinder 43. One end of the insulating pad 5 abuts against the pad bracket, and the other end is clamped to the winding 4 through the slot. By using the insulating pads 5 at both ends of the winding 4, the winding 4 is pressed and fixed between the upper clamp 31 and the lower clamp 32.

[0031] In a preferred embodiment of this application, a plurality of cooling fans 6 are installed on the base 1; the transformer provided by this application for use in tunnels in earthquake zones can also be connected to an external temperature controller. The external temperature controller uses sensors to inspect the hot spots of the transformer and controls the start and stop of the cooling fans 6 under certain temperature conditions, or adjusts the air inlet angle of the cooling fans 6 to achieve the technical effect of efficient heat dissipation.

[0032] In the above technical solution, a phase spacer 421 is provided between the high-voltage coils 42, and the two ends of the phase spacer 421 are fixed on the upper clamp 31 and the lower clamp 32 respectively. The phase spacer 421, as the main insulation component, prevents phase-to-phase short circuits by physically separating the windings 4 of different phases. It can reduce the transverse length of the transformer while ensuring the insulation performance of the transformer.

[0033] This application provides a transformer for use in earthquake-prone tunnels. The low-voltage coil 41 and high-voltage coil 42 are cast with epoxy resin, which can withstand the electrodynamic forces generated during short circuits, ensuring safe and reliable operation in earthquake zones without causing environmental pollution. The use of phase spacers 421 and insulating cylinders 43 reduces the space occupied by the transformer while ensuring the insulation performance of the windings 4. The use of an automatically controlled cooling fan 6 optimizes the air intake angle of the transformer, improving the heat dissipation effect and reliability.

[0034] The technical solution adopted in this application is conducive to the separate installation of transformers in tunnels in earthquake zones. By making reasonable use of space and flexibly arranging the layout, it can reduce voltage fluctuations, improve voltage stability, and improve power quality.

[0035] This invention also provides a transformer seismic simulation method in this embodiment, which specifically includes the following steps: Establish a transformer structure simulation model; In this step, a finite element mechanical model is established for the overall structure of the transformer. During discretization, hexahedral elements are predominantly used, with a very small number of prismatic elements. The finite element mechanical model for transformer structural simulation is as follows: Figure 5 As shown, the Y direction is the vertical direction.

[0036] Static analysis is used to determine the maximum stress in a transformer. In this step, static analysis is used to evaluate the structural performance of the transformer under static load. During the analysis, the strength is assessed by the inertial force corresponding to the acceleration on the X, Y, and Z axes respectively. The acceleration on the X-axis is taken as 1g, the acceleration on the Y-axis is taken as 3g, and the acceleration on the Z-axis is taken as 1g, where g is the acceleration due to gravity. In this embodiment, the static analysis obtained that the maximum stress of the transformer is 271.72MPa, which is located on the skeleton channel steel 11 of the base 1 and does not exceed the yield strength of Q355NE material of 355MPa.

[0037] Modal analysis is used to obtain the first-order vibration frequency of the transformer; In this step, the purpose of modal analysis is to calculate the natural frequencies of the transformer structure and determine the vibration mode of the structure, thereby determining the overall or local stiffness of the transformer structure. The first-order vibration frequency of the transformer is used to characterize the lowest frequency vibration characteristics of the transformer structure due to material properties when there is no external excitation. In this embodiment, the first-order vibration frequency of the transformer is 29.98Hz. The first-order vibration frequency combined with the mode shape diagram can identify the weak stiffness areas of the transformer structure.

[0038] Response spectrum analysis is used to obtain the equivalent stress distribution of the transformer under simulated seismic load and the maximum stress obtained from the response spectrum analysis. In this step, response spectrum analysis is used to evaluate the peak response of the transformer structure at different frequencies; during the analysis, loads are applied to the transformer structure in the X, Y, and Z axes according to Table 1 (Response Spectrum Analysis Loading Data Table); , Specifically, the single-condition loading time is 30 minutes, the loading time per axis is 12 hours, and the total loading time is 36 hours. The acceleration scaling factors for the X, Y, and Z axes are calculated and obtained separately. Based on the acceleration scaling factors for the X, Y, and Z axes, the maximum stress for response spectrum analysis is calculated and obtained for each axis. The maximum stress of the response spectrum is also known as the Von Mises maximum stress. The maximum stress of the response spectrum simplifies the three-dimensional stress state into a single equivalent value, quantifying whether the material is close to its yield limit. In this embodiment, it is used to quantify the risk of yielding or failure of transformer materials under dynamic load conditions, identify stress concentration areas in the model, and help determine the most dangerous parts.

[0039] Based on the formula for calculating the acceleration proportionality coefficient, the acceleration proportionality coefficients for the X, Y, and Z axes are calculated respectively. The formula for calculating the acceleration proportionality coefficient is as follows: , In the formula: ∆ is the acceleration proportionality coefficient; t Minimum stress range; ∆ s The maximum stress range; α1 and α2 are both constants; N t N is the minimum load cycle number; s The maximum load cycle number; typical values ​​for the exponents m1 and m2 are 3 to 9.

[0040] Fatigue analysis is performed based on the maximum stress of the transformer response spectrum to predict the fatigue strength of the transformer structure. In this step, based on the maximum stress analyzed by the response spectrum, and according to the Miner linear fatigue cumulative damage calculation formula and the SN curve of the transformer material, the damage of the transformer in the X, Y, and Z axis directions is calculated respectively; specifically, the Miner linear fatigue cumulative damage calculation formula is: , In the formula: D is the damage value; N f ∆ is the number of load cycles; The stress range is given; the typical value of the exponent m is 3 to 9; α is a constant.

[0041] In this embodiment, the maximum stress in the X-axis response spectrum analysis of the transformer structure is 10.42 MPa, located at the upper clamp; the maximum stress in the Y-axis response spectrum analysis is 6.93 MPa, located at the base; and the maximum stress in the Z-axis response spectrum analysis is 33.86 MPa, located at the base. The sum of the overall damage of the transformer structure in the X, Y, and Z axes is less than 1, which meets the fatigue strength requirements.

[0042] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A transformer seismic simulation method, characterized in that, Includes the following steps: Establish a transformer structure simulation model; Static analysis is used to determine the maximum stress in a transformer. Modal analysis is used to obtain the first-order vibration frequency of the transformer. The first-order vibration frequency of the transformer is used to characterize the lowest frequency vibration characteristics of the transformer structure due to material properties when there is no external excitation. Response spectrum analysis is used to obtain the equivalent stress distribution of the transformer under simulated seismic load and the maximum stress obtained from the response spectrum analysis. Fatigue analysis is performed based on the maximum stress of the transformer response spectrum to predict the fatigue strength of the transformer structure.

2. The transformer seismic simulation method according to claim 1, characterized in that, The static analysis was performed using the inertial forces corresponding to the accelerations on the X, Y, and Z axes, respectively. The acceleration on the X axis was taken as 1g, the acceleration on the Y axis as 3g, and the acceleration on the Z axis as 1g, where g is the acceleration due to gravity.

3. The transformer seismic simulation method according to claim 1, characterized in that, During the response spectrum analysis, loads were applied to the X, Y, and Z axes respectively, with a single-condition loading time of 30 minutes and a loading time of 12 hours per axis. The acceleration proportionality coefficients of the X, Y, and Z axes were calculated and obtained respectively. Based on the acceleration proportionality coefficients of the X, Y, and Z axes, the maximum stress of the response spectrum analysis of the X, Y, and Z axes was calculated and obtained respectively.

4. The transformer seismic simulation method according to claim 1, characterized in that, The fatigue analysis based on the maximum stress using the transformer response spectrum analysis includes the following steps: Based on the maximum stress analyzed by response spectrum, and according to Miner's linear fatigue cumulative damage calculation formula, the damage of the transformer in the X, Y, and Z axis directions is calculated respectively.

5. The transformer seismic simulation method according to claim 4, characterized in that, The Miner linear fatigue cumulative damage calculation formula is as follows: ， In the formula: D is the damage value; N f ∆ is the number of load cycles; The stress range is given; the typical value of the exponent m is 3 to 9; α is a constant.

6. The transformer seismic simulation method according to claim 3, characterized in that, In the step of calculating the acceleration proportionality coefficients for the X, Y, and Z axes respectively, the formula for calculating the acceleration proportionality coefficient is: ， In the formula: ∆ is the acceleration proportionality coefficient; t Minimum stress range; ∆ s The maximum stress range; α1 and α2 are both constants; N t N is the minimum load cycle number; s The maximum load cycle number; typical values ​​for the exponents m1 and m2 are 3 to 9.

7. A transformer for use in tunnels within earthquake zones, used to implement the transformer seismic simulation method as described in any one of claims 1 to 6, characterized in that, The transformer used in the earthquake zone tunnel includes: Base; An iron core is located above the base; the iron core includes: a plurality of iron core columns and an upper iron yoke and a lower iron yoke located at both ends of the iron core columns respectively; A core clamping component, comprising an upper clamping component and a lower clamping component, wherein the upper clamping component clamps the upper yoke, and the lower clamping component is connected to the base and clamps the lower yoke, thereby fixing the core to the base; A winding, disposed between the upper clamp and the lower clamp, comprising: A plurality of low-voltage coils, wherein the low-voltage coils are epoxy resin foil windings, and the plurality of the low-voltage coils are respectively sleeved on the outside of the iron core column; A plurality of high-voltage coils, wherein the high-voltage coils are epoxy resin wire-wound coils, and the plurality of high-voltage coils are respectively sleeved on the outside of the low-voltage coil; An insulating cylinder is disposed between the low-voltage coil and the high-voltage coil; Insulating pads, a plurality of the insulating pads are respectively disposed between the winding and the iron core clamp, for pressing and fixing the winding.

8. A transformer for use in tunnels in earthquake zones according to claim 7, characterized in that, The lower clamping member includes: A first clamping plate is fixed to the base. The second clamping plate is fixed to the base and is parallel to the first clamping plate; A tensioning screw passes through the first clamping plate and the second clamping plate, and bolts are respectively provided at both ends of the tensioning screw; A clamping insulating plate is disposed on the inner side of the first clamping plate, the inner side of the second clamping plate, and the surface of the base; A core pad is disposed inside the insulating plate of the clamp, and the core pad is adapted to the shape of the lower yoke surface.

9. A transformer for use in tunnels within earthquake zones according to claim 7, characterized in that, A double-layer insulating cylinder is provided between the low-voltage coil and the high-voltage coil. Gaps for insulation and heat dissipation are provided between the insulating cylinder and the low-voltage coil, between the insulating cylinders themselves, and between the insulating cylinder and the high-voltage coil.

10. A transformer for use in a tunnel in an earthquake zone according to claim 7, characterized in that, A phase spacer is provided between the high-voltage coils, and the two ends of the phase spacer are respectively fixed to the upper clamp and the lower clamp.

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