Calculation method and system for radial bending safety factor of winding considering spacer width

Abstract

The present invention discloses a method and system for calculating the radial bending safety factor of a winding considering the width of spacers. The influence of the width of transformer spacers is considered in the constructed critical warping stress model of transformer winding conductors, making the calculation of the critical warping stress of transformer winding conductors more accurate, improving the accuracy of the radial bending safety factor of the transformer winding under the action of short-circuit current, and solving the technical problem that the radial bending safety factor of the transformer winding calculated by the existing calculation method of the radial bending safety factor of the transformer winding under the action of short-circuit current is not accurate, does not conform to the actual value, and it is difficult to accurately evaluate the radial short-circuit resistance ability of the transformer winding.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and particularly to a calculation method and system for the radial bending safety factor of windings considering the width of spacers. Background Art

[0002] A transformer is an important component of a power system, and the health level and operating condition thereof are directly related to the safety and stability of the operation of the power system. When a transformer suffers a sudden short-circuit fault, a large short-circuit current flows through the windings, so that a large electromagnetic force acts on the coils, which may cause the performance of the transformer windings to decline. In particular, for the windings located in the inner layer, under the action of the short-circuit current, due to the inward pressure, special attention should be paid to the problem of radial warping of the windings. In the existing methods for calculating the radial bending safety factor of transformer windings under the action of short-circuit current, the influence of the width of the winding spacers on the radial warping stress of the windings is not considered, and the obtained radial bending safety factor of the transformer windings under the action of short-circuit current is not accurate and does not conform to the actual value, making it difficult to accurately evaluate the radial short-circuit resistance ability of the transformer windings. Summary of the Invention

[0003] The present invention provides a calculation method and system for the radial bending safety factor of windings considering the width of spacers, which is used to solve the technical problem that the calculated radial bending safety factor of the transformer windings under the action of short-circuit current by the existing calculation method is not accurate, does not conform to the actual value, and makes it difficult to accurately evaluate the radial short-circuit resistance ability of the transformer windings.

[0004] In view of this, the first aspect of the present invention provides a calculation method for the radial safety factor of a transformer winding considering the width of spacers, including:

[0005] Construct a critical warping stress model for the transformer winding conductors considering the width of spacers. The critical warping stress model for the transformer winding conductors is:

[0006]

[0007] where σ c is the critical warping stress of the transformer winding conductors, E(σ) is the elastic modulus of the transformer winding conductors, k is the equivalent radial width coefficient, t is the radial width of the transformer winding conductors, x is the circumferential angle corresponding to the arc length of half the width of the transformer winding spacers, S is the winding arc length between two adjacent spacers without considering the width of the spacers, N is the number of spacers of a single transformer winding, and R is the circumferential equivalent radius of the transformer winding;

[0008] Calculate the critical warping stress of the transformer winding conductors according to the critical warping stress model of the transformer winding conductors;

[0009] Apply a short - circuit fault to the transformer winding, and calculate the radial bending safety factor of the transformer winding under the action of short - circuit current according to the critical warping stress of the transformer winding conductor.

[0010] Optionally, calculate the critical warping stress of the transformer winding conductor according to the critical warping stress model of the transformer winding conductor, including:

[0011] Use the Newton - Raphson iteration method to solve the critical warping stress model of the transformer winding conductor. When the iteration termination condition is reached, output the critical warping stress of the transformer winding conductor as the critical warping stress of the transformer winding conductor under the action of short - circuit current.

[0012] Optionally, the iteration termination condition is:

[0013]

[0014] Where, is the critical warping stress of the transformer winding conductor at the (n + 1)-th iteration, is the critical warping stress of the transformer winding conductor at the n - th iteration, and ε is the iteration accuracy.

[0015] Optionally, the calculation formula for the elastic modulus E(σ) of the transformer winding conductor is:

[0016]

[0017] Where, E0 is the slope at the origin of the stress - strain curve of the transformer winding material, and γ, σ0, q are fitting coefficients obtained through stress - strain test experiments on the transformer winding conductor.

[0018] Optionally, the calculation formula for the radial bending safety factor of the transformer winding under the action of short - circuit current is:

[0019]

[0020] Where, SF is the radial bending safety factor of the transformer winding under short - circuit current, and σ total is the total stress on the transformer winding conductor under short - circuit current.

[0021] Optionally, apply a short - circuit fault to the transformer winding, and calculate the radial bending safety factor of the transformer winding under the action of short - circuit current according to the critical warping stress of the transformer winding conductor, including:

[0022] Apply a short - circuit fault to the transformer winding, and obtain the circumferential pressure on the transformer winding conductor under the action of short - circuit current;

[0023] According to the circumferential pressure on the transformer winding conductor under the action of short - circuit current, calculate the circumferential stress of the transformer winding under short - circuit current;

[0024] Calculate the strain of the transformer winding wire under short - circuit current according to the circumferential stress of the transformer winding under short - circuit current;

[0025] Calculate the total strain of the transformer winding wire according to the strain of the transformer winding wire under short - circuit current and the initial strain during winding of the transformer winding wire;

[0026] Calculate the total stress on the transformer winding wire according to the total strain of the transformer winding wire;

[0027] Calculate the radial bending safety factor of the transformer winding under short - circuit current according to the critical warping stress of the transformer winding wire and the total stress on the transformer winding wire.

[0028] The second aspect of the present invention provides a system for calculating the radial safety factor of a transformer winding considering the width of spacers, including:

[0029] A model construction module for constructing a critical warping stress model of the transformer winding wire considering the width of spacers. The critical warping stress model of the transformer winding wire is:

[0030]

[0031] where σ c is the critical warping stress of the transformer winding wire, E(σ) is the elastic modulus of the transformer winding wire, k is the equivalent radial width coefficient, t is the radial width of the transformer winding wire, x is the circumferential angle corresponding to the arc length of half the width of the transformer winding spacer, S is the winding arc length between two adjacent spacers without considering the spacer width, N is the number of spacers in a single transformer winding, and R is the circumferential equivalent radius of the transformer winding;

[0032] A critical warping stress calculation module for calculating the critical warping stress of the transformer winding wire according to the critical warping stress model of the transformer winding wire;

[0033] A radial bending safety factor calculation module for applying a short - circuit fault to the transformer winding and calculating the radial bending safety factor of the transformer winding under short - circuit current according to the critical warping stress of the transformer winding wire.

[0034] Optionally, the critical warping stress calculation module is specifically used for:

[0035] Use the Newton - Raphson iteration method to solve the critical warping stress model of the transformer winding wire. When the iteration termination condition is reached, output the critical warping stress of the transformer winding wire as the critical warping stress of the transformer winding wire under short - circuit current.

[0036] Optionally, the iteration termination condition is:

[0037]

[0038] Among them, is the critical warping stress of the transformer winding conductor at the (n + 1)-th iteration, is the critical warping stress of the transformer winding conductor at the n-th iteration, and ε is the iteration accuracy.

[0039] Optionally, the calculation formula for the elastic modulus E(σ) of the transformer winding conductor is:

[0040]

[0041] Among them, E0 is the slope at the origin of the stress-strain curve of the transformer winding material, and γ, σ0, and q are fitting coefficients obtained through stress-strain test experiments on the transformer winding conductor.

[0042] Optionally, the calculation formula for the radial bending safety factor of the transformer winding under the action of short-circuit current is:

[0043]

[0044] Among them, SF is the radial bending safety factor of the transformer winding under short-circuit current, and σ total is the total stress on the transformer winding conductor under short-circuit current.

[0045] It can be seen from the above technical solutions that the method and system for calculating the radial critical warping stress of a transformer winding considering the spacer width provided by the present invention have the following advantages:

[0046] The method and system for calculating the radial critical warping stress of a transformer winding considering the spacer width provided by the present invention consider the influence of the spacer width of the transformer in the constructed critical warping stress model of the transformer winding conductor, making the calculation of the critical warping stress of the transformer winding conductor more accurate, improving the accuracy of the radial bending safety factor of the transformer winding under the action of short-circuit current, and solving the technical problem that the radial bending safety factor of the transformer winding under the action of short-circuit current calculated by the existing calculation method of the radial bending safety factor of the transformer winding under the action of short-circuit current is not accurate, does not fit the actual value, and it is difficult to accurately evaluate the radial short-circuit resistance ability of the transformer winding. Description of the Drawings

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0048] Figure 1 It is a schematic flow chart of the calculation method for the radial safety factor of a transformer winding considering the width of the spacer provided in the present invention;

[0049] Figure 2 It is a partial equivalent schematic diagram of a transformer winding - spacer provided in the present invention;

[0050] Figure 3 It is a schematic diagram of a transformer winding wire before winding provided in the present invention;

[0051] Figure 4 It is a deformation schematic diagram of a transformer winding wire after winding provided in the present invention;

[0052] Figure 5 It is a schematic structural diagram of a calculation system for the radial safety factor of a transformer winding considering the width of the spacer provided in the present invention. Detailed implementation manners

[0053] In order to enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0054] For ease of understanding, please refer to Figure 1 , an embodiment of the calculation method for the radial safety factor of a transformer winding considering the width of the spacer provided in the present invention includes:

[0055] Step 101: Construct a critical warping stress model for the transformer winding wire considering the width of the spacer.

[0056] It should be noted that the critical warping stress model for the transformer winding wire constructed in the embodiments of the present invention is:

[0057]

[0058] Among them, σ cσ is the critical warping stress of the transformer winding conductor, E(σ) is the elastic modulus of the transformer winding conductor, k is the equivalent radial width coefficient, t is the radial width of the transformer winding conductor, x is the circumferential angle corresponding to the arc length of half the width of the transformer winding spacer, S is the winding arc length between two adjacent spacers excluding the spacer width, N is the number of spacers in a single transformer winding, and R is the circumferential equivalent radius of the transformer winding.

[0059] As Figure 2 shown, Figure 2 Figure is a partial equivalent schematic diagram of the transformer winding - spacer, Figure 2 In it, 1 and 2 respectively represent two spacers, the thick black arc represents the winding, S represents the winding arc length between two adjacent spacers excluding the spacer width, S a represents the spacer width, x represents the circumferential angle corresponding to the arc length of half the width of the transformer winding spacer, β represents the circumferential angle between the centerlines of two adjacent spacers, and β' = 0.5β.

[0060] Therefore, the calculation formula for the winding arc length S between two adjacent spacers excluding the spacer width is:

[0061]

[0062] where, N is the number of spacers in a single transformer winding, E(σ) is the elastic modulus of the transformer winding conductor, the transformer winding conductor is generally a copper conductor, and R is the circumferential equivalent radius of the transformer winding.

[0063] Based on the CIGRE calculation method, the critical stress when the winding section between two spacers warps can be calculated by the following formula:

[0064]

[0065] where, D is the circumferential equivalent diameter of the transformer winding, i.e., D = 2R, k is the equivalent radial width coefficient, and t is the radial width of the transformer winding conductor.

[0066] When not considering the spacer width, that is, the winding arc length (including the spacer width) S0 between two spacers is:

[0067]

[0068] Substituting Equation (3) into Equation (2), we can get:

[0069]

[0070] When considering the spacer width, substituting Equation (1) into Equation (2), we can get:

[0071]

[0072] The circumferential angle x corresponding to the arc length of half the width of the transformer winding spacer is greater than 0. Therefore, considering the spacer width, the critical buckling stress is less than the case without considering the spacer width. In the actual calculation of the critical buckling stress of the transformer winding conductor, the spacer width should be considered to be closer to the actual application.

[0073] Step 102: Calculate the critical buckling stress of the transformer winding conductor according to the critical buckling stress model of the transformer winding conductor.

[0074] It should be noted that according to the Ramberg - Osgood model of stress - strain near the yield point of the material described by classical solid mechanics, the elastic modulus E(σ) of the transformer winding conductor can be obtained as:

[0075]

[0076] where E0 is the slope at the origin of the stress - strain curve of the transformer winding material, and γ, σ0, q are the fitting coefficients obtained through stress - strain test experiments on the transformer winding conductor.

[0077] After substituting Equation (6) into Equation (5), the critical buckling stress model of the transformer winding conductor can be expressed as:

[0078]

[0079] The critical buckling stress σ of the transformer winding conductor can be calculated according to the critical buckling stress model of the transformer winding conductor c . Specifically, the critical buckling stress model of the transformer winding conductor can be solved by the Newton - Raphson iteration method. Assume:

[0080]

[0081]

[0082] where n is the number of iterations. The derivative result of f(σ c ) is:

[0083]

[0084] When the iteration condition meets the following conditions, the iteration is terminated to obtain the final critical buckling stress of the transformer winding conductor. The iteration termination condition is:

[0085]

[0086] where is the critical buckling stress of the transformer winding conductor at the (n + 1) - th iteration, is the critical warping stress of the transformer winding conductor at the nth iteration, and ε is the iteration accuracy.

[0087] Step 103: Apply a short-circuit fault to the transformer winding, and calculate the radial bending safety factor of the transformer winding under the action of the short-circuit current according to the critical warping stress of the transformer winding conductor.

[0088] It should be noted that the critical warping stress σ of the transformer winding conductor calculated by considering the spacer width as above c is used to calculate the radial bending safety factor of the transformer winding under the action of the short-circuit current, specifically as follows:

[0089]

[0090] where SF is the radial bending safety factor of the transformer winding under the short-circuit current, and σ total is the total stress on the transformer winding conductor under the short-circuit current.

[0091] For the total stress σ on the transformer winding conductor under the short-circuit current total , it can be calculated by using the calculation method of the existing technology, or it can be calculated by using the following method provided by the embodiments of the present invention:

[0092] Apply a short-circuit fault to the transformer winding, so that a short-circuit current occurs in the transformer winding, and thus the annular pressure F on the transformer winding conductor under the action of the short-circuit current can be obtained rad .

[0093] After obtaining the annular pressure F on the transformer winding conductor under the action of the short-circuit current rad , the annular stress σ of the transformer winding under the short-circuit current can be calculated.

[0094] Under the action of the short-circuit current, the transformer winding is subjected to an inward annular stress. For the winding section between two spacers, the formula for calculating the annular stress it receives is:

[0095]

[0096] where σ is the annular stress of the transformer winding under the short-circuit current, and F rad is the annular pressure on the transformer winding conductor under the action of the short-circuit current, l is the distance between the spacers of the transformer winding, and h is the axial height of the transformer winding conductor.

[0097] The conductor of the transformer winding is generally a copper conductor. According to the Ramberg-Osgood model of the copper conductor, the strain in the radial direction of the transformer winding conductor under the short-circuit current can be calculated:

[0098]

[0099] Among them, ε0, σ0, and m are constants obtained through stress-strain test experiments on the transformer winding conductors, and ε is the strain of the transformer winding conductors under short-circuit current.

[0100] The total strain of the transformer winding conductors takes into account the influence of the initial strain during the winding of the transformer winding conductors. Therefore, the total strain of the transformer winding conductors is the superposition of the strain of the transformer winding conductors under short-circuit current and the initial strain during the winding of the transformer winding conductors. That is:

[0101] ε total = ε w + ε

[0102] Among them, ε total is the total strain of the transformer winding conductors, and ε w is the initial strain during the winding of the transformer winding conductors.

[0103] Figure 3 is a schematic diagram before the winding of the transformer winding conductors, Figure 4 is a schematic diagram of the deformation after the winding of the transformer winding conductors. Among them, AB is the center line segment of the conductor, PQ is the line segment at a preset distance y from the center AB of the transformer winding conductors, P*Q* is the line segment after PQ is wound around the circumferential center C*, A*B* is the line segment after AB is wound around the circumferential center C*, and Δθ * is the central angle corresponding to P * Q * after the winding of the transformer winding conductors, Δx is the length of PQ, and Δx * is the length of P*Q*, and ρ is the average radius of the winding of a single transformer winding conductor. As Figure 3 and Figure 4 shown, after the conductor is wound around the circumferential center C*, PQ is shortened to P*Q*, and the length of the conductor center AB can be considered to remain unchanged after winding, that is, AB = PQ = A*B*. At the same time, before and after winding, AP = BQ = y = A*P* = B*Q*. Therefore, it can be calculated that after the conductor is wound, the strain ε w at any distance y from the conductor center AB is:

[0104]

[0105] The total stress σ total on the transformer winding conductors under short-circuit current is:

[0106]

[0107] Among them, σ total is the total stress on the transformer winding conductors.

[0108] The total stress σ on the transformer winding conductor provided by the embodiment of the present invention total When calculating, the initial strain of the transformer winding conductor during winding and the strain of the transformer winding conductor under short-circuit current are considered simultaneously, which is beneficial to improving the accuracy of the radial bending safety factor of the transformer winding under the action of short-circuit current.

[0109] The method for calculating the radial critical warping stress of a transformer winding considering the spacer width provided by the embodiment of the present invention takes into account the influence of the transformer spacer width in the constructed critical warping stress model of the transformer winding conductor, making the calculation of the critical warping stress of the transformer winding conductor more accurate, improving the accuracy of the radial bending safety factor of the transformer winding under the action of short-circuit current, and solving the technical problem that the radial bending safety factor of the transformer winding calculated by the existing calculation method of the radial bending safety factor of the transformer winding under the action of short-circuit current is not accurate, does not conform to the actual value, and it is difficult to accurately evaluate the radial short-circuit resistance ability of the transformer winding.

[0110] For ease of understanding, please refer to Figure 5 , an embodiment of a system for calculating the radial safety factor of a transformer winding considering the spacer width is provided in the present invention, including:

[0111] A model construction module for constructing a critical warping stress model of a transformer winding conductor considering the spacer width, and the critical warping stress model of the transformer winding conductor is:

[0112]

[0113] wherein, σ c is the critical warping stress of the transformer winding conductor, E(σ) is the elastic modulus of the transformer winding conductor, k is the equivalent radial width coefficient, t is the radial width of the transformer winding conductor, x is the circumferential angle corresponding to the arc length of half the width of the transformer spacer, S is the winding arc length between two adjacent spacers without considering the spacer width, N is the number of spacers of a single transformer winding, and R is the circumferential equivalent radius of the transformer winding;

[0114] A critical warping stress calculation module for calculating the critical warping stress of the transformer winding conductor according to the critical warping stress model of the transformer winding conductor;

[0115] A winding radial bending safety factor calculation module for applying a short-circuit fault to the transformer winding and calculating the radial bending safety factor of the transformer winding under the action of short-circuit current according to the critical warping stress of the transformer winding conductor.

[0116] The critical warping stress calculation module is specifically used for:

[0117] The Newton-Raphson iteration method is used to solve the critical buckling stress model of the transformer winding conductor. When the iteration termination condition is reached, the critical buckling stress of the transformer winding conductor is output as the critical buckling stress of the transformer winding conductor under the action of the short-circuit current.

[0118] The iteration termination condition is:

[0119]

[0120] where, is the critical buckling stress of the transformer winding conductor at the (n + 1)-th iteration, is the critical buckling stress of the transformer winding conductor at the n-th iteration, and ε is the iteration accuracy.

[0121] The calculation formula for the elastic modulus E(σ) of the transformer winding conductor is:

[0122]

[0123] where, E0 is the slope at the origin of the stress-strain curve of the transformer winding material, and γ, σ0, q are the fitting coefficients obtained through the stress-strain test on the transformer winding conductor.

[0124] The calculation formula for the radial bending safety factor of the transformer winding under the action of the short-circuit current is:

[0125]

[0126] where, SF is the radial bending safety factor of the transformer winding under the short-circuit current, and σ total is the total stress on the transformer winding conductor under the short-circuit current.

[0127] The radial bending safety factor calculation module is specifically used for:

[0128] Applying a short-circuit fault to the transformer winding to obtain the annular pressure on the transformer winding conductor under the action of the short-circuit current;

[0129] Calculating the annular stress of the transformer winding under the short-circuit current according to the annular pressure on the transformer winding conductor under the action of the short-circuit current;

[0130] Calculating the strain of the transformer winding conductor under the short-circuit current according to the annular stress of the transformer winding under the short-circuit current;

[0131] Calculating the total strain of the transformer winding conductor according to the strain of the transformer winding conductor under the short-circuit current and the initial strain during the winding of the transformer winding conductor;

[0132] Calculating the total stress on the transformer winding conductor according to the total strain of the transformer winding conductor.

[0133] Calculate the radial bending safety factor of the transformer winding under the action of short-circuit current according to the critical warping stress of the transformer winding conductor and the total stress received by the transformer winding conductor.

[0134] The system for calculating the radial critical warping stress of a transformer winding considering the spacer width provided by the embodiment of the present invention is used to execute the method for calculating the radial critical warping stress of a transformer winding considering the spacer width in the embodiment of the method for calculating the radial critical warping stress of a transformer winding considering the spacer width. Its principle is the same as that of the method for calculating the radial critical warping stress of a transformer winding considering the spacer width in the embodiment of the method for calculating the radial critical warping stress of a transformer winding considering the spacer width, and will not be elaborated here.

[0135] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating the radial safety factor of a transformer winding considering the width of the spacer, characterized in that, Including: Construct a critical warping stress model for the transformer winding conductor considering the spacer width. The critical warping stress model for the transformer winding conductor is: Among them, σ c is the critical warping stress of the transformer winding conductor, E(σ) is the elastic modulus of the transformer winding conductor, k is the equivalent radial width coefficient, t is the radial width of the transformer winding conductor, x is the circumferential angle corresponding to the arc length of half the width of the transformer winding spacer, S is the winding arc length between two adjacent spacers excluding the spacer width, N is the number of spacers in a single transformer winding, and R is the circumferential equivalent radius of the transformer winding; Calculate the critical warping stress of the transformer winding conductor according to the critical warping stress model of the transformer winding conductor; Apply a short-circuit fault to the transformer winding, and calculate the radial bending safety factor of the transformer winding under the action of the short-circuit current according to the critical warping stress of the transformer winding conductor; The calculation formula for the elastic modulus E(σ) of the transformer winding conductor is: Wherein, E0 is the slope at the origin of the stress-strain curve of the transformer winding material, and γ, σ0, and q are fitting coefficients obtained through stress-strain test experiments on the transformer winding conductor; The calculation formula for the radial bending safety factor of the transformer winding under the action of the short-circuit current is: Among them, SF is the radial bending safety factor of the transformer winding under short-circuit current, and σ total is the total stress on the transformer winding conductor under short-circuit current.

2. The method for calculating the radial safety factor of a transformer winding considering the width of the spacer according to claim 1, characterized in that Calculating the critical warping stress of the transformer winding conductor according to the critical warping stress model of the transformer winding conductor includes: Using the Newton-Raphson iteration method to solve the critical warping stress model of the transformer winding conductor. When the iteration termination condition is reached, output the critical warping stress of the transformer winding conductor as the critical warping stress of the transformer winding conductor under the action of the short-circuit current.

3. The method for calculating the radial safety factor of a transformer winding considering the width of the spacer according to claim 2, characterized in that, The iteration termination condition is: Among them, is the critical warping stress of the transformer winding conductor at the (n + 1)-th iteration, is the critical warping stress of the transformer winding conductor at the n-th iteration, and ε is the iteration accuracy.

4. The method for calculating the radial safety factor of a transformer winding considering the width of the spacer according to claim 1, characterized in that Applying a short-circuit fault to the transformer winding, and calculating the radial bending safety factor of the transformer winding under the action of the short-circuit current according to the critical warping stress of the transformer winding conductor includes: Apply a short-circuit fault to the transformer winding to obtain the annular pressure on the transformer winding conductor under the action of the short-circuit current; Calculate the annular stress of the transformer winding under the short-circuit current according to the annular pressure on the transformer winding conductor under the action of the short-circuit current; Calculate the strain of the transformer winding conductor under the short-circuit current according to the annular stress of the transformer winding under the short-circuit current; Calculate the total strain of the transformer winding conductor according to the strain of the transformer winding conductor under the short-circuit current and the initial strain during the winding of the transformer winding conductor; Calculate the total stress on the transformer winding conductor according to the total strain of the transformer winding conductor; Calculate the radial bending safety factor of the transformer winding under the action of the short-circuit current according to the critical warping stress of the transformer winding conductor and the total stress on the transformer winding conductor.

5. A calculation system for the radial safety factor of a transformer winding considering the width of spacers, characterized in that, Including: A model construction module for constructing a critical warping stress model for the transformer winding conductor considering the spacer width. The critical warping stress model for the transformer winding conductor is: Among them, σ c is the critical warping stress of the transformer winding conductor, E(σ) is the elastic modulus of the transformer winding conductor, k is the equivalent radial width coefficient, t is the radial width of the transformer winding conductor, x is the circumferential angle corresponding to the arc length of half the width of the transformer winding spacer, S is the winding arc length between two adjacent spacers excluding the spacer width, N is the number of spacers in a single transformer winding, and R is the circumferential equivalent radius of the transformer winding; A critical warping stress calculation module for calculating the critical warping stress of the transformer winding conductor according to the critical warping stress model of the transformer winding conductor; A winding radial bending safety factor calculation module for applying a short-circuit fault to the transformer winding and calculating the radial bending safety factor of the transformer winding under the action of the short-circuit current according to the critical warping stress of the transformer winding conductor; The calculation formula for the elastic modulus E(σ) of the transformer winding conductor is: Wherein, E0 is the slope at the origin of the stress-strain curve of the transformer winding material, and γ, σ0, and q are fitting coefficients obtained through stress-strain test experiments on the transformer winding conductor; The calculation formula for the radial bending safety factor of the transformer winding under the action of the short-circuit current is: Among them, SF is the radial bending safety factor of the transformer winding under short-circuit current, and σ total is the total stress on the transformer winding conductor under short-circuit current.

6. The calculation system for the radial safety factor of a transformer winding considering the width of the spacer according to claim 5, characterized in that, The critical warping stress calculation module is specifically used for: The Newton-Raphson iteration method is used to solve the critical buckling stress model of the transformer winding conductor. When the iteration termination condition is reached, the critical buckling stress of the transformer winding conductor is output as the critical buckling stress of the transformer winding conductor under the action of the short-circuit current.

7. The calculation system for the radial safety factor of a transformer winding considering the width of spacers according to claim 6, characterized in that The iteration termination condition is: Among them, is the critical warping stress of the transformer winding conductor at the (n + 1)-th iteration, is the critical warping stress of the transformer winding conductor at the n-th iteration, and ε is the iteration accuracy.

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