Anti-explosion calculation method for plugging of converter transformer valve side sleeve hole

Abstract

The invention relates to the technical field of extra-high voltage direct current transmission, and discloses an anti-explosion calculation method for converter transformer valve side sleeve hole plugging, which comprises the following steps: arranging an anti-explosion and fireproof integrated plug with an anti-explosion framework at a hole, and providing anti-explosion bearing capacity by the anti-explosion framework; explosive shock wave overpressure borne by the plugging surface is simplified into equivalent evenly-distributed overpressure according to the midspan bending moment equal principle, and then the equivalent evenly-distributed overpressure is further simplified into equivalent static pressure based on the dynamics principle. An anti-knock framework is simplified into a simply-supported member with two hinged ends, and anti-knock performance evaluation is realized by verifying that the bending resistance of the simply-supported member is not less than a midspan equivalent static bending moment and the equivalent corner of a support of a node connected with a firewall does not exceed an allowable corner. By means of the method, the integrally-plugged anti-explosion framework meets the anti-explosion bearing capacity and deformation requirements and can be applied to actual engineering, the method does not need to depend on a full-scale explosion test, the method is suitable for hole plugging scenes of different sizes and different structures, the engineering applicability is improved, and the technical application cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of extra-high voltage direct current transmission, in particular to an anti-explosion calculation method for valve-side bushing hole plugging of a converter transformer. BACKGROUND

[0002] The converter transformer is the core equipment of the extra-high voltage direct current transmission system. The valve-side bushing needs to pass through the firewall of the valve hall to connect with the converter valve, and the bushing hole formed thereby is a weak part of the valve hall structure. Since the converter transformer stores a large amount of insulating oil inside during operation, there is a risk of explosion caused by the combustion or vaporization of insulating oil when a fault (such as short circuit, overheating, etc.) occurs in the equipment. The shock wave generated by such an explosion will directly impact the hole plugging structure. If the plugging fails, not only will it damage other equipment in the valve hall, but it may also cause the power grid to be interrupted, seriously threatening the safety of the power system.

[0003] In order to improve the anti-explosion performance of the valve-side bushing hole plugging of the transformer, in recent years, the valve-side bushing hole of the valve hall firewall of the converter station of the extra-high voltage direct current transmission project generally adopts an integrated plugging scheme with anti-explosion and fireproof functions. The integrated plugging usually adopts an anti-explosion and fireproof plate with a stainless steel perforated plate, an intermediate bearing frame, and a symmetric mirror image configuration of the anti-explosion and fireproof plate, wherein the intermediate bearing frame is usually made of stainless steel or other high-performance materials to enhance the anti-explosion capability of the structure.

[0004] Related prior art, such as Chinese invention patent with publication number CN113158489A, provides a calculation method for the wall thickness of an anti-explosion pipeline based on equivalent load. This method is applicable to scenarios where the explosion medium is flammable gas and the anti-explosion structure is tubular. It is mainly used to calculate the wall thickness of the pipeline under the action of equivalent load. However, there are significant differences between its application scenarios and the plate-shaped plugging structure of the valve-side bushing hole of the converter transformer, and it cannot be directly applied. In addition, Chinese utility model patent with publication number CN218714299U provides a valve hall converter transformer valve-side bushing hole fireproof and anti-explosion plugging structure. This scheme proposes a plugging plate structure that combines anti-explosion and fireproof functions. It uses UHPC as the anti-explosion framework and stainless steel perforated plates and cement fiber plates as the fireproof layer to achieve functional integration. However, this scheme only provides the structural design of the plugging structure and does not involve the calculation method of the anti-explosion bearing capacity. In practice, its anti-explosion performance is mainly verified through full-scale model explosion impact tests. For projects with inconsistent hole span, structure, and test conditions (especially for hole modification projects in operating and converter stations), the applicability is poor, and it is difficult to apply.

[0005] Therefore, for the anti-explosion and fireproof integrated plugging of the valve-side bushing hole of the converter transformer, there is an urgent need for an anti-explosion bearing capacity calculation method that can adapt to different sizes and structures to replace the traditional method that relies on test verification, reduce technical application costs, and improve engineering applicability. SUMMARY

[0006] The application aims to provide a blast-resistant calculation method for valve-side bushing hole plugging of a converter transformer, so as to solve the technical problems in the background art.

[0007] To achieve the above-mentioned purpose, the application discloses the following technical scheme: a blast-resistant calculation method for valve-side bushing hole plugging of a converter transformer, the method comprising the following steps:

[0008] An integrated plugging for blast-resistant fire prevention is arranged at the hole of the valve-side bushing of the converter transformer, and an anti-blast framework is arranged in the integrated plugging, which provides blast-resistant bearing capacity for the integrated plugging;

[0009] The blast shock wave overpressure borne by the surface of the integrated plugging is simplified into equivalent uniform shock wave overpressure according to the principle of equal cross-mid-span bending moment ;

[0010] The integrated plugging is split into a plurality of modules along the vertical direction, wherein the two ends of each module are fixedly connected with the firewalls to form connection nodes, and the adjacent modules are connected through a tongue-and-groove joint; and the anti-blast framework is simplified into a simply supported member with the two ends hinged as fulcrums of the connection nodes, wherein the span of the anti-blast framework is the distance between the two connection nodes;

[0011] The equivalent uniform shock wave overpressure borne by the surface of the integrated plugging is converted into equivalent static pressure through dynamic pressure ;

[0012] The bending resistance of the anti-blast framework is verified, and when the bending resistance of the anti-blast framework is greater than or equal to the cross-mid-span equivalent static bending moment calculated from the equivalent static pressure ; the bending resistance requirement is met;

[0013] The support equivalent rotation angle of the anti-blast framework is verified, wherein when the anti-blast framework is subjected to the equivalent static pressure, the support equivalent rotation angle generated at the connection node of the anti-blast framework and the firewall is less than or equal to the allowable rotation angle of the connection node ; the deformation requirement is met.

[0014] As a preferred embodiment, the equivalent uniform shock wave overpressure is calculated by the following formula: ;

[0015] ​​​​​

[0016] in, The peak reflected overpressure of the explosion shock wave borne by the integrated sealing surface is used as the target value for the explosion-proof performance of the valve side bushing opening of the converter transformer. It is obtained by actual measurement using a pressure sensor placed on the integrated sealing surface closest to the explosive. The equivalent mean value coefficient of shock wave overpressure.

[0017] Preferably, the equivalent mean value coefficient of the shock wave overpressure is calculated using the following formula:

[0018]

[0019] in, The distance between the location of the casing explosion and the sealing point; Width of a single module; The span of the blast-resistant frame; The explosion shock wave overpressure at any point on the integrated sealing surface is obtained through actual measurement or numerical calculation of the explosion of a spherical TNT charge in a uniform free field.

[0020] Preferably, the uniformly distributed equivalent static pressure It is calculated using the following formula:

[0021]

[0022] in, This is the equivalent static pressure coefficient.

[0023] Preferably, based on the principles of structural dynamics, the equivalent static pressure coefficient is simplified to:

[0024]

[0025] in, To simplify the blast-resistant frame into a single-degree-of-freedom system, the corresponding natural vibration period is... ; The subordinate mass of the blast-resistant frame is determined through structural calculations of the integrated sealing structure; For the structural rigidity of the blast-resistant frame, ,in The elastic modulus of the blast-resistant skeleton material. The moment of inertia of the cross section of the blast-resistant frame; The effective duration of the explosive impact load is measured by a pressure sensor located on the integrated sealing surface closest to the explosive. The span of the blast-resistant frame.

[0026] Preferably, the flexural resistance of the blast-resistant frame is... It is calculated using the following formula:

[0027]

[0028] in, The flexural modulus of a single module of the explosion-proof frame; This represents the bending design value of the explosion-proof skeleton material.

[0029] Preferably, the bending design value of the explosion-proof skeleton material is calculated using the following formula:

[0030]

[0031] in, This refers to the standard value of the material strength of the explosion-proof frame.

[0032] Preferably, the equivalent static bending moment across the span It is calculated using the following formula:

[0033]

[0034] in, Width of a single module; The span of the blast-resistant frame.

[0035] Preferably, the equivalent rotation angle of the support It is calculated using the following formula:

[0036]

[0037] in, For the elastoplastic deformation of the blast-resistant frame, The span of the blast-resistant frame.

[0038] Preferably, the elastic-plastic deformation of the blast-resistant frame is calculated using the following formula:

[0039]

[0040] in, For the structural rigidity of the blast-resistant frame, , The elastic modulus of the blast-resistant skeleton material. The moment of inertia of the cross section of the blast-resistant frame.

[0041] Compared with the prior art, the explosion-proof calculation method for sealing the valve-side bushing opening of the converter transformer of the present invention has the following advantages:

[0042] 1. This invention provides a quantitative method for calculating blast resistance capacity, solving the problem that existing technologies rely on full-scale model explosion impact tests to verify the blast resistance performance of integrated blast-resistant and fireproof sealing systems. In existing technologies, sealing structures with different opening spans and constructions require experimental verification. However, this invention, based on explosion engineering, structural mechanics, and accumulated experimental data, establishes a systematic calculation method that can evaluate blast resistance performance without relying on experiments, thus improving the versatility of the technology.

[0043] 2. It has strong applicability and can be widely applied to sealing scenarios of valve-side bushing openings of converter transformers of different sizes and structures. Whether it is an opening of different spans and module widths in a newly built project, or an opening renovation project in an operating converter station, the explosion-proof performance can be evaluated by the calculation method of this invention, overcoming the shortcomings of existing technologies that are highly dependent on test conditions and have limited applicability.

[0044] 3. The mechanical concepts are clear, the calculation process is simple, and it is easy to apply in engineering practice. This invention simplifies the overpressure of the explosion shock wave to an equivalent uniformly distributed overpressure, and further simplifies it to an equivalent static pressure. It also simplifies the blast-resistant frame to a simply supported component and a single-degree-of-freedom system. Combined with clear calculation formulas, this allows engineering technicians to directly apply it to actual design and evaluation, thus lowering the technical application threshold.

[0045] 4. Compared with the traditional verification method that relies on full-scale explosion tests, the present invention can complete the explosion resistance performance evaluation through theoretical calculations, avoiding the large amount of manpower and material resources required for testing, shortening the technical verification cycle, and is especially suitable for the modification of in-operation projects that are sensitive to cost and construction period.

[0046] 5. By calculating the equivalent mid-span bending moment and support rotation angle of the blast-resistant frame and comparing them with the bending resistance and allowable rotation angle, the load-bearing capacity and deformation performance of the frame can be quantitatively verified, providing a clear basis for the design of the blast-resistant frame, ensuring the safety of the sealing structure under the impact of an explosion, ensuring the blast-resistant reliability of the sealing structure, and further improving the disaster prevention and mitigation capabilities of the converter station valve hall. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 A flowchart illustrating the explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer, provided for an embodiment of the present invention.

[0049] Figure 2A schematic diagram of an explosion test provided for an embodiment of the present invention;

[0050] Figure 3 A schematic diagram of the integrated sealing device provided for an embodiment of the present invention;

[0051] Figure 4 This is a simplified schematic diagram illustrating the calculation principle of the equivalent mean coefficient of shock wave overpressure provided in an embodiment of the present invention;

[0052] Figure 5 A schematic diagram showing the equivalent mean coefficient of shock wave overpressure and the numerical calculation results provided for embodiments of the present invention. Detailed Implementation

[0053] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] In this document, the term "comprising" is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0055] This embodiment provides a method such as Figure 1 The explosion-proof calculation method for sealing the bushing opening on the valve side of the converter transformer, as shown, aims to meet the technical requirements for disaster prevention, mitigation, and fire protection upgrades in ultra-high voltage converter stations. Specifically, the method includes the following steps:

[0056] S1 - Determine the blast-resistant load-bearing structure of the integrated sealing system.

[0057] An integrated seal for explosion-proof and fire-resistant purposes is installed at the opening of the converter transformer valve-side bushing. The integrated seal contains an explosion-proof frame, which provides explosion-proof load-bearing capacity. It should be noted that the valve-side bushing refers to the bushing used on the valve side of the converter transformer, passing through the valve hall firewall and connecting to the converter valve; the integrated seal refers to a composite structure with built-in steel or inorganic high-performance composite material as the frame, supplemented by fire-resistant materials, providing both explosion-proof and fire-resistant functions for sealing the converter transformer valve-side bushing opening in the valve hall firewall. Feasibly, referring to engineering practice, in this embodiment, the explosion-proof frame of the integrated seal uses two 150×80×8mm stainless steel pipes (material S30408), with a cross-sectional bending modulus of... Standard value of material strength elastic modulus Moment of inertia of cross section .

[0058] S2 - Calculate the equivalent uniformly distributed shock wave overpressure

[0059] According to such Figure 2 An explosion test was conducted on the layout shown. The overpressure of the explosion shock wave borne by the integrated sealing surface was simplified to an equivalent uniformly distributed shock wave overpressure based on the principle of equal mid-span bending moment. It should be noted that shock wave reflection overpressure refers to the pressure value exceeding the surrounding atmospheric pressure within the compression zone of the explosion shock wave, which acts normally on the integrated sealing surface.

[0060] In this embodiment, the equivalent uniformly distributed shock wave overpressure It is calculated using the following formula:

[0061]

[0062] in, The peak reflected overpressure of the explosive shock wave borne by the integrated sealing surface is used as the target value for the explosion-proof performance of the converter transformer valve-side bushing opening seal. This value is obtained through actual measurement using a pressure sensor positioned on the integrated sealing surface closest to the explosive. In this embodiment, the explosion-proof target value is set as follows: .

[0063] The equivalent mean value coefficient for shock wave overpressure is calculated using the following formula:

[0064]

[0065] in, The distance between the location of the casing explosion and the sealing point; Width of a single module (i.e., the integrated sealing unit is vertically divided into multiple modules); The span of the blast-resistant frame; The overpressure of the explosion shock wave at any point on the integrated sealing surface is obtained through actual measurement or numerical calculation of the explosion of a spherical TNT charge in a uniform free field. In this embodiment, the distance between the casing explosion point and the sealing is... (Refer to explosion-proof test setup) The width L of the bushing opening on the valve side of the converter transformer is generally 2.0~5.0m, and the width of the integrated sealing module is split vertically. (Select the intermediate module that is closest to the casing and experiences the most unfavorable stress). Based on engineering practice, The following fitting formula can be used for approximate calculation:

[0066]

[0067] in, The module width correction factor can be obtained from Table 1 below. Secondly, the calculation principle is as follows: Figure 4 As shown, the relationship between the equivalent mean value coefficient α of the shock wave overpressure calculated by the above formula and the numerical calculation result is as follows: Figure 5 As shown.

[0068] Table 1

[0069] Module width B(m) 0.5 1 1.5 2.0 2.5 3.0 3.5 4.0 φ 1.000 0.989 0.972 0.950 0.921 0.893 0.859 0.828

[0070] Specifically, referring to engineering practice, the width of the bushing opening on the valve side of the converter transformer in this embodiment is... The value is 5.0m, module width. Taking the intermediate module, which is closest to the casing and experiences the most unfavorable stress, as the target, a depth of 0.7m is used. Based on this, the calculations for this embodiment are performed. , .

[0071] S3 - Simplified Mechanical Model of Blast-Resistant Frame

[0072] Considering the large size of the bushing opening on the valve side of the converter transformer, for ease of installation, such as Figure 2 As shown, the integrated sealing device is vertically divided into multiple relatively uniform modules, including module 1, module 2, module 3, module 4, and module 5, where module 3 is the middle module. The widths of each module are B1, B2, B3, B4, and B5, respectively. The two ends of each module are fixedly connected to the firewall to form connection nodes, and adjacent modules are connected by tongue and groove joints. The blast-resistant frame is simplified as a simply supported member with both ends hinged around the connection nodes as fulcrums, where the span of the blast-resistant frame is the distance between the two connection nodes.

[0073] S4 - Calculate equivalent static pressure

[0074] The equivalent uniformly distributed shock wave overpressure borne by the integrated sealing surface The dynamic pressure is simplified to a uniformly distributed equivalent static pressure. Specifically, the uniformly distributed equivalent static pressure It is calculated using the following formula:

[0075]

[0076] in, This is the equivalent static pressure coefficient.

[0077] Furthermore, based on the principles of structural dynamics, the equivalent static pressure coefficient is simplified to:

[0078]

[0079] in, To simplify the blast-resistant frame into a single-degree-of-freedom system, the corresponding natural vibration period is... .

[0080] The mass of the blast-resistant frame is determined through structural calculations of the integrated seal. Based on engineering practice, the total thickness of the integrated seal is approximately 150mm, corresponding to a weight per unit area of ​​approximately... This embodiment is based on Considering, then .

[0081] For the structural rigidity of the blast-resistant frame, ,in The elastic modulus of the blast-resistant skeleton material. The moment of inertia of the cross section of the blast-resistant frame, Let S be the span of the blast-resistant frame. Substituting the corresponding parameters, we get:

[0082] but .

[0083] The effective duration of the explosive impact load is measured by a pressure sensor positioned closest to the explosive on the integrated sealing surface. Specifically, this embodiment references the results of multiple actual blast resistance performance tests on opening sealing. Substitute and calculate :

[0084] Therefore .

[0085] Furthermore, calculations yielded... .

[0086] S5 - Verify the bending resistance of the blast-resistant frame

[0087] The following needs to be met: the bending resistance of the blast-resistant frame. Greater than or equal to the equivalent static pressure distributed uniformly Calculated equivalent static bending moment across span The bending resistance of the blast-resistant frame It is calculated using the following formula:

[0088]

[0089] in, The flexural modulus of the section of the blast-resistant frame; This refers to the flexural design value of the blast-resistant frame material. The flexural design value of the blast-resistant frame material is calculated using the following formula:

[0090]

[0091] in, This refers to the standard value of the material strength of the explosion-proof frame. Specifically, the standard value of the material strength of the S30408 ​​stainless steel explosion-proof frame is taken as... ,but Substituting the parameters, the bending resistance of the blast-resistant frame is calculated. .

[0092] Furthermore, the equivalent static bending moment across the span It is calculated using the following formula:

[0093]

[0094] in, Width of a single module; The span of the blast-resistant frame is taken as the width of the opening.

[0095] Substituting the parameters, we get: .

[0096] Based on the bending resistance of the blast-resistant frame obtained above, It meets the requirements for bending resistance.

[0097] S6 - Verify the equivalent rotation angle of the support

[0098] The following conditions must be met: the explosion-proof frame must withstand a uniformly distributed equivalent static pressure. Under its influence, the equivalent turning angle of the support generated at the connection node with the firewall. Less than or equal to the allowable rotation angle of the connection node In this embodiment, the built-in stainless steel explosion-proof frame support is designed to allow deformation. The equivalent rotation angle of the support. It is calculated using the following formula:

[0099]

[0100] in, For the elastoplastic deformation of the blast-resistant frame, The span of the blast-resistant frame is given. The elastic-plastic deformation of the blast-resistant frame is calculated using the following formula:

[0101]

[0102] in, For the structural rigidity of the blast-resistant frame, , The elastic modulus of the blast-resistant skeleton material. The moment of inertia of the cross section of the blast-resistant frame.

[0103] Substituting the parameters, we get: .

[0104] but .

[0105] Based on the above-obtained equivalent rotation angle of the support It meets the deformation requirements.

[0106] In summary, the explosion-proof calculation method for sealing the valve-side bushing opening of the converter transformer, as described in this embodiment, demonstrates that the integrated sealing explosion-proof frame meets the requirements for explosion-proof bearing capacity and deformation, and can be applied to practical engineering projects. Furthermore, this method does not rely on full-scale explosion tests and is applicable to sealing openings of different sizes and structures, improving engineering applicability and reducing technical application costs. Referring to this embodiment, the 5000×5000×150mm composite fireproof and explosion-proof integrated sealing structure, after being subjected to a shock wave with a peak pressure of 550kPa, showed cracking of the fireproof board on the explosion-facing side and no significant change on the explosion-proof back side, further demonstrating the applicability of this invention.

[0107] In the embodiments provided by this invention, it should be understood that the embodiments described herein can be implemented in hardware, software, firmware, middleware, code, or any suitable combination thereof. For hardware implementation, the processor can be implemented in one or more of the following: application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, other electronic units designed to implement the functions described herein, or combinations thereof. For software implementation, some or all of the processes of the embodiments can be performed by a computer program instructing the associated hardware. During implementation, the program can be stored in a computer-readable storage medium or transmitted as one or more instructions or code on a computer-readable storage medium. Computer-readable storage media include computer storage media and communication media, wherein communication media include any medium that facilitates the transmission of a computer program from one place to another. Storage media can be any available medium accessible to a computer. Computer-readable storage media can include, but are not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code having the form of instructions or data structures and accessible to a computer.

[0108] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for explosion-proof calculation of sealing the valve-side bushing opening of a converter transformer, characterized in that, The method includes the following steps: An integrated seal for explosion-proof and fire-proofing is installed at the opening of the bushing on the valve side of the converter transformer. The integrated seal is equipped with an explosion-proof skeleton, which provides explosion-proof bearing capacity for the integrated seal. The overpressure of the explosion shock wave borne by the integrated sealing surface is simplified to an equivalent uniformly distributed shock wave overpressure based on the principle of equal mid-span bending moment. ; The integrated blockade is vertically divided into multiple modules, wherein the two ends of each module are fixedly connected to the firewall to form connection nodes, and adjacent modules are connected by tongue and groove joints; and the blast-resistant frame is simplified into a simply supported member with the two ends hinged together with the connection nodes as fulcrums, wherein the span of the blast-resistant frame is the distance between the two connection nodes. The equivalent uniformly distributed shock wave overpressure borne by the integrated sealing surface The dynamic pressure is simplified to a uniformly distributed equivalent static pressure. ; Bending resistance against burst skeleton The bending resistance of the blast-resistant frame was verified. Greater than or equal to the equivalent static pressure distributed uniformly Calculated equivalent static bending moment across span At that time, the bending resistance requirement is met; Equivalent rotation angle of the support against the burst skeleton The verification was conducted, wherein the explosion-proof frame was subjected to a uniformly distributed equivalent static pressure. Under its influence, when the support equivalent turning angle generated at the connection node with the firewall... Less than or equal to the allowable rotation angle of the connection node At that time, the deformation requirements are met.

2. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 1, characterized in that, The equivalent uniformly distributed shock wave overpressure It is calculated using the following formula: in, The peak reflected overpressure of the explosion shock wave borne by the integrated sealing surface is used as the target value for the explosion-proof performance of the valve side bushing opening of the converter transformer. It is obtained by actual measurement using a pressure sensor placed on the integrated sealing surface closest to the explosive. The equivalent mean value coefficient of shock wave overpressure.

3. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 2, characterized in that, The equivalent mean value coefficient of the shock wave overpressure is calculated using the following formula: in, The distance between the location of the casing explosion and the sealing point; Width of a single module; The span of the blast-resistant frame; The explosion shock wave overpressure at any point on the integrated sealing surface is obtained through actual measurement or numerical calculation of the explosion of a spherical TNT charge in a uniform free field.

4. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 1, characterized in that, The uniformly distributed equivalent static pressure It is calculated using the following formula: in, This is the equivalent static pressure coefficient.

5. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 4, characterized in that, Based on the principles of structural dynamics, the equivalent static pressure coefficient is simplified to: in, To simplify the blast-resistant frame into a single-degree-of-freedom system, the corresponding natural vibration period is... ; The subordinate mass of the blast-resistant frame is determined through structural calculations of the integrated sealing structure; For the component stiffness of the blast-resistant frame, ,in The elastic modulus of the blast-resistant skeleton material. The moment of inertia of the cross section of the blast-resistant frame; The effective duration of the explosive impact load is measured by a pressure sensor located on the integrated sealing surface closest to the explosive. The span of the blast-resistant frame.

6. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 1, characterized in that, Bending resistance of the blast-resistant frame It is calculated using the following formula: in, The flexural modulus of a single module of the explosion-proof frame; This represents the bending design value of the explosion-proof skeleton material.

7. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 6, characterized in that, The flexural design value of the blast-resistant skeleton material is calculated using the following formula: in, This refers to the standard value of the material strength of the explosion-proof frame.

8. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 1, characterized in that, The equivalent static bending moment across the span It is calculated using the following formula: in, Width of a single module; The span of the blast-resistant frame.

9. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 1, characterized in that, The equivalent rotation angle of the support It is calculated using the following formula: in, For the elastoplastic deformation of the blast-resistant frame, The span of the blast-resistant frame.

10. The explosion-proof calculation method for sealing the valve-side bushing opening of a converter transformer according to claim 9, characterized in that, The elastic-plastic deformation of the blast-resistant frame is calculated using the following formula: in, For the component stiffness of the blast-resistant frame, , The elastic modulus of the blast-resistant skeleton material. The moment of inertia of the cross section of the blast-resistant frame.

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