Transformer iron core section optimization method and system based on dynamic programming

Abstract

The invention belongs to the field of transformer design, and particularly relates to a transformer iron core section optimization method and system based on dynamic programming, and the method comprises the following steps: 1) inputting a given iron core diameter and parameter data, and building a mathematical model of a transformer iron core section according to a transformer iron core design structure; 2) obtaining a selectable sheet width set according to the established mathematical model of the cross section of the transformer iron core; 3) according to the selectable sheet width set, establishing a dynamic programming recursion formula to obtain an optimal result of the cross section of the transformer core; 4) visually displaying the optimal result of the cross section of the transformer iron core, judging whether the optimal result meets requirements or not, and if the optimal result meets the requirements, exporting corresponding document data and uploading the document data to a database for storage; and if not, returning to execute the step 1). According to the method, the final purposes of full coverage of scheme combination and global optimization of the calculation result are achieved, meanwhile, the operation efficiency is high, the time complexity is low, and the overall cost of the transformer is better reduced through the global optimal section design.

Description

Technical Field

[0001] The invention belongs to the field of transformer design, and in particular relates to a transformer core cross-section optimization method and system based on dynamic programming. Background Art

[0002] The transformer industry is a traditional manufacturing industry. After the rapid technological advancement in recent years, the differences in technology and manufacturing between domestic and foreign transformer manufacturers have gradually become smaller and even disappeared. Industry competition has become increasingly fierce, which requires more sophisticated transformer design to ensure performance while achieving optimal cost.

[0003] A crucial step in transformer design is the core cross-section. The core cross-section, in terms of shape, is approximately circular, formed by stacking multiple rectangular sections. The fill factor of each rectangular section relative to the core diameter is a key factor in transformer core design. Improving the fill factor can reduce transformer production costs. The ultimate goal of core cross-section optimization is to calculate a filling scheme that maximizes the core fill factor within certain design constraints. From a design perspective, this is a combinatorial problem. However, the number of combinations increases exponentially with increasing core diameter, necessitating the use of computer programs to assist in the calculation and selection of optimal solutions. Currently, the industry largely relies on standard cross-sections found in books and manuals, corresponding to core diameters that are multiples of 10 and cannot meet the requirements of precise design. Computer optimization programs often employ analytical or randomized algorithms, such as genetic algorithms, ant colony algorithms, and particle swarm algorithms. These algorithms require manual manipulation of the tuning parameters. Often, due to inappropriate parameter selection, they converge at suboptimal points, resulting in suboptimal optimization results. In addition, from the perspective of the calculation program, the program can only calculate the required cross-sectional data and cannot provide graphical data for subsequent design. The generated data cannot be shared by other design platforms within the system. Summary of the Invention

[0004] The purpose of the present invention is to provide a transformer core cross-section optimization method and system design based on dynamic programming, which solves the non-optimal convergence problem of existing algorithms and obtains the global optimal solution while ensuring the operating efficiency of the program. In addition, the program development method provided provides a good user interaction carrier for the algorithm. After the calculation is completed, a real-time graphical preview of the results is realized, which is convenient for designers to check and adjust, and also realizes the output of drawings and the intercommunication and transmission of platform data.

[0005] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: a transformer core cross-section optimization method based on dynamic programming, comprising the following steps:

[0006] 1) Input the given core diameter and parameter data, and establish the mathematical model of the transformer core cross section according to the transformer core design structure;

[0007] 2) Obtaining a set of optional core widths based on the established mathematical model of the transformer core cross section;

[0008] 3) Based on the set of optional core widths, a dynamic programming recursive formula is established to obtain the optimal transformer core cross-section;

[0009] 4) Visualize the optimal result of the transformer core cross-section and determine whether it meets the requirements. If so, export the corresponding document data and upload it to the database for storage; if not, return to step 1).

[0010] The transformer core design structure is specifically as follows: the width of each stage is W i The thickness of each sheet is h, and the thickness of each sheet is h. i is an integer, the target level number M, the minimum level width W M is a fixed value.

[0011] In step 1), the mathematical model of the transformer core cross section is established as follows:

[0012] The width of the core main sheet W1 < the core diameter D, and the set of all optional sheet widths is obtained, namely: W M ~W1, width of each level W i are all multiples of 10, increasing in steps of 10; then M slice widths are selected from the slice width set, satisfying the following conditions:

[0013] h i =H i –H i-1 , 1≤i≤M

[0014] H0=0

[0015] W i 2 +H i 2 ≤R 2 i∈[1,M]

[0016] Among them, M is the target level, h i is the thickness of the i-th level, H i is the total stack thickness of the i-th level, W i is the width of the i-th level slice, W i It is a multiple of 10, and R is the core radius.

[0017] The optional sheet width set includes: sheet width quantity count, sheet width, and corresponding total stack thickness.

[0018] In step 2), the obtaining of the set of optional chip widths is specifically as follows:

[0019] Obtain the relationship formula of the number of chip widths, chip widths, and corresponding total stack thicknesses in the set of optional chip widths, that is:

[0020]

[0021]

[0022]

[0023] Among them, count represents the number of chip widths, W i is the chip width of the i-th level, H i is the total stack thickness of the i-th level, R is the core radius, W M is the minimum-level chip width.

[0024] The said step 3) is specifically as follows:

[0025] (1) Solve the optimal result of the transformer core cross-section according to the dynamic programming algorithm, and establish the dynamic programming recurrence formula:

[0026] Among them, lt and rt are the subscripts in the chip width set array, 0 ≤ lt < r ≤ count, ct is the number of levels to be taken out from the chip width set array, W rt is the chip width with the subscript rt in the chip width set array, H rt is the total stack thickness corresponding to W rt [[ID= chip width, H lt is the total stack thickness corresponding to the chip width with the subscript lt in the chip width set array, m is the recursive variable of the number of levels taken out, and l is the recursive variable of the subscript selection.

[0027] (2) According to the dynamic programming recurrence formula, the functional formula for the optimal result of the core cross-section is:

[0028] f(0, count, M)

[0029] Among them, count represents the number of chip widths, and M is the target number of levels.

[0030] In the recursive process of the dynamic programming algorithm, there are redundant identical sub-problems. Through the parameter dictionary, the results of the corresponding sub-problems in the execution process of the dynamic programming algorithm are cached, and the results of the sub-problems calculated during the recursive process are directly returned to avoid recalculation of redundant sub-problems and improve the execution efficiency of the algorithm.

[0031] A transformer core cross-section optimization system based on dynamic programming includes: a main interface unit, a data input module, a logic operation module, a vector graphics drawing module, and an output and persistence module;

[0032] The main interface unit is used to visualize the transformer core cross-section optimization process and the optimal result of the transformer core cross-section;

[0033] The data input module is used to configure the default values ​​of other parameters corresponding to the core diameter. When inputting, only the core diameter is input to read the default values ​​of other parameters, and the obtained data is sent to the logic operation module;

[0034] The logic operation module is used to read the core diameter and other corresponding parameters sent by the data input module, obtain a set of optional sheet widths based on the established mathematical model of the transformer core cross section, and perform recursive calculations based on the dynamic programming algorithm to obtain the optimal result of the transformer core cross section;

[0035] The vector graphics drawing module is used to convert the received transformer core cross-section optimal result into graphic information, store it in a graphic set, and visually draw it on the main interface unit and output a CAD file to provide graphic data;

[0036] The output and persistence module is used for CAD drawing output, transformer core section calculation document storage, and transformer core section data upload to the database.

[0037] The main interface unit adopts the MFC framework and performs functional expansion and packaging according to interaction requirements.

[0038] The main interface unit includes: a function area, a property bar, a canvas document, and an output bar;

[0039] Functional area, used to perform functional actions in the optimization process;

[0040] The attribute column is the attribute table, which is used to enter the parameters related to the calculation of core diameter and core cross section;

[0041] The canvas document is a canvas area for drawing vector graphics of the core cross section. The vector graphics drawing module displays the graphics set in the canvas document area through GDI graphics programming technology and renders the graphics data through graphic elements.

[0042] The output column is used to output the optimal results of the transformer core cross-section and display them visually at the corresponding position.

[0043] The present invention has the following beneficial effects and advantages:

[0044] 1. The transformer core cross-section optimization algorithm based on dynamic programming provided by the present invention achieves full coverage of scheme combinations and the ultimate goal of global optimal calculation results. At the same time, it has high operating efficiency and low time complexity. The globally optimal cross-section design is more conducive to reducing the overall cost of the transformer.

[0045] 2. The transformer core cross-section optimization program development method provided by the present invention adopts an MFC framework design, which provides a better user experience; all program parameters can be defaulted, and there is no need to enter a large amount of data; the calculated results are displayed graphically in real time, which is convenient for designers to review, check and adjust in real time, and is more in line with the designer's drawing habits; the generated graphics can be exported as CAD drawing files and uploaded to the database, providing graphic and data support for the subsequent electromagnetic scheme design and structural design.

[0046] 3. The transformer core cross-section optimization algorithm and program development method based on dynamic programming of the present invention have been applied to the electromagnetic scheme and structural design of actual transformer products, which has reduced the cost of the design scheme and greatly improved the design efficiency and design quality of designers. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a schematic diagram of the cross-sectional structure of the iron core of the present invention;

[0048] Figure 2 This is a schematic diagram of the main interface unit of the present invention;

[0049] Figure 3 Flowchart for the method of the present invention. DETAILED DESCRIPTION

[0050] The specific implementation methods of the present invention are described in detail below with reference to the accompanying drawings and specific examples, but the examples are not intended to limit the present invention. Similar methods and similar changes using the present invention are all within the scope of protection of the present invention.

[0051] like Figure 3 FIG. 1 is a flowchart of the method of the present invention, wherein the method for optimizing the cross-section of a transformer core based on dynamic programming comprises the following steps:

[0052] 1) Input the given core diameter and parameter data, and establish the mathematical model of the transformer core cross section according to the transformer core design structure;

[0053] 2) Obtaining a set of optional core widths based on the established mathematical model of the transformer core cross section;

[0054] 3) Based on the set of optional core widths, a dynamic programming recursive formula is established to obtain the optimal transformer core cross-section;

[0055] 4) Visualize the optimal result of the transformer core cross-section and determine whether it meets the requirements. If so, export the corresponding document data and upload it to the database for storage; if not, return to step 1).

[0056] like Figure 1The figure is a schematic diagram of the cross-sectional structure of the core of the present invention. The transformer core design structure of the present invention is specifically as follows: the width of each level is W i The thickness of each sheet is h, and the thickness of each sheet is h. i is an integer, the target level number M, the minimum level width W M is a fixed value.

[0057] 1) Establish a mathematical model for the optimization problem

[0058] Core cross-section structure diagram Figure 1 , under a given core diameter D (radius R), according to the requirements of the transformer design structure, the width W of each level i The thickness of each sheet is h, which is a multiple of 10 and cannot exceed the range of the core diameter D after stacking. i is an integer, the target level number M, the minimum level width W M is a fixed value.

[0059] Since the width of the core main sheet W1 < the core diameter D, the set of all optional sheet widths can be obtained (W M ~W1, are multiples of 10, increasing in steps of 10), then the problem is transformed into selecting M slice widths from the slice width set, and satisfying the following mathematical description:

[0060] h i =H i –H i-1 , 1≤i≤M

[0061] H0=0

[0062] W i 2 +H i 2 ≤R 2 i∈[1,M]

[0063] Among them, M is the target level, h i is the thickness of the i-th level, H i is the total stack thickness of the i-th level, W i is the width of the i-th level slice, W i It is a multiple of 10, and R is the core radius.

[0064] 2) Determine the optional slice width set elements

[0065] Get the relationship between the number of slice widths, slice widths, and the corresponding total stacking thickness in the optional slice width set, namely:

[0066]

[0067]

[0068]

[0069] Among them, count represents the number of sheet widths, W i is the sheet width of the i-th level, H i is the total stacking thickness of the i-th level, R is the core radius, W M is the minimum sheet width.

[0070] 3) Establish the dynamic programming recurrence formula

[0071] (1) Solve the optimal result of the transformer core cross-section according to the dynamic programming algorithm, and establish the dynamic programming recurrence formula:

[0072]

[0073] Among them, lt and rt are the subscripts in the sheet width set array, 0 ≤ lt < r ≤ count, ct is the number of levels to be taken out from the sheet width set array, W rt is the sheet width with the subscript rt in the sheet width set array, H rt is W rt the total stacking thickness corresponding to the sheet width, H lt is the total stacking thickness corresponding to the sheet width with the subscript lt in the sheet width set array, m is the recursive variable of the number of levels taken out, and l is the recursive variable of the subscript selection.

[0074] (2) The functional formula for obtaining the optimal result of the core cross-section is:

[0075] f(0, count, M)

[0076] Among them, count represents the number of sheet widths, and M is the target number of levels.

[0077] (3) There are redundant identical sub-problems in the recursive process of the dynamic programming algorithm. Through the parameter dictionary, the results of the corresponding sub-problems in the execution process of the dynamic programming algorithm are cached, and the results of the sub-problems calculated during the recursive process are directly returned to avoid recalculation of redundant sub-problems and improve the execution efficiency of the algorithm.

[0078] The method for optimizing the transformer core cross-section based on dynamic programming of the present invention is implemented based on the transformer core cross-section optimization system, and the system includes: a main interface unit, a data input module, a logic operation module, a vector graphics drawing module, and an output and persistence module;

[0079] The main interface unit is based on the property sheet control PropertyCtrl of the MFC framework, and is functionally extended and encapsulated according to the interaction requirements, and is used for visual display of the optimization steps of the transformer core cross-section and the optimal result of the transformer core cross-section;

[0080] The data input module includes reading in default values, executing the optimization algorithm, and graphing the result data. Except for the core diameter parameter, all other parameters in the program input interface can be left blank. For the parameters that are not filled in, the corresponding relationship between the specified core diameter range and the corresponding parameter value is given through the configuration file. The program reads the configuration file at the beginning of the logic operation to assign the default parameters. The optimization algorithm is the core of the logic operation, which is the dynamic programming optimization algorithm described in the present invention. The algorithm traverses all possible combinations in a recursive manner, and at the same time caches the results of the execution of each recursive parameter during the recursive process. The cached parameter results are directly called to avoid repeated calculations of the same recursive parameters, thereby ensuring the time complexity of the algorithm while obtaining the global optimal solution, and the obtained global optimal solution is sent to the logic operation module;

[0081] The logic operation module is used to read the core diameter and other corresponding parameters sent by the data input module, obtain the optional sheet width set based on the established mathematical model of the transformer core cross section, and perform recursive calculations based on the dynamic programming algorithm to obtain the optimal result of the transformer core cross section;

[0082] The vector graphics drawing module, used to convert the received optimal transformer core cross-section results into graphical information, converts the data into graphics and tabular information, stores it in a graphics collection, and provides graphic data for vector graphics drawing and CAD file output. Using object-oriented thinking, it defines various primitive classes, such as lines, circles, arcs, dimensions, and text, all of which inherit from the primitive base class. Based on the desired drawing style, graphics of different types and sizes are created in different locations and stored in the graphics collection. These graphics are then visually drawn on the main interface unit and provided as graphic data for CAD file output. Vector graphics drawing design is a pre-display of graphics. Using GDI graphics programming techniques, the resulting graphics collection generated by logical execution is displayed in the canvas document area, and scaling and moving the canvas document is supported. Because vector graphics drawing eliminates the need for data transfer with CAD drawing software, program stability and execution speed are significantly improved, enhancing design efficiency.

[0083] The output and persistence module is used for CAD drawing output, transformer core cross-section calculation document storage, and transformer core cross-section data upload to the database. CAD drawing output utilizes the COM interface provided by the CAD drawing software. Based on the graphics collection generated by the logic operation, the program calls the constructors of different primitives (such as AddLine and AddCircle) according to their type. Each graphic in the graphic element collection is created in the CAD drawing software and saved as a CAD drawing file. Input data and logic operation results are stored as data documents via the Serialize function of the MFC framework multi-document program. The result data obtained from the logic operation is stored in the database using the SQL scripting language, facilitating data reference within the parametric design platform.

[0084] like Figure 2 The figure shows a schematic diagram of the main interface unit of the present invention. The main interface unit includes: a function area, a property bar, a canvas document, and an output bar, providing a friendly operation interface.

[0085] Function buttons such as open, save, execute calculation, output structure data table, output CAD graphics, and upload structure data are defined in the function area;

[0086] The property column is a property table used to enter parameters related to core section calculation;

[0087] The canvas document is the canvas area where the core cross-section vector graphics are drawn, and the graphic elements are rendered into this area;

[0088] The output column is the data of the core section width, stacking thickness and other data after the program executes the calculation, the main interface unit.

[0089] The optimization program operation flow chart is shown in Figure 3 The specific execution process of the optimization program is described below. After entering the program's main interface, you first enter data such as core diameter, minimum stage chord height, number of stages, and temperature rise information. The program uses the configuration file to set the default values ​​for other parameters corresponding to the core diameter. When entering, simply enter the core diameter to read the default values ​​for other parameters, or you can manually modify the actual values.

[0090] After entering data, click the Execute Calculation button in the ribbon to begin recursive calculations using the dynamic programming algorithm. Upon completion, the algorithm generates results such as total cross-sectional area, slice widths at each level, stack thickness, oil passages, and corner weight. The resulting data is visualized in the canvas document, displayed as proportional cross-sectional drawings and data tables. Designers can review the results and decide whether to adjust detailed parameters and recalculate.

[0091] If the generated results meet the design requirements, the results will be persisted, including exporting cross-section CAD drawings, saving cross-section calculation documents, and uploading cross-section data to the database to provide data for subsequent design drawings and parametric design platforms.

[0092] Example 1:

[0093] The following description will be made by taking an embodiment in which the core diameter is 662 mm as an example.

[0094] The core section optimization algorithm is based on the dynamic programming algorithm, and the main technology of the program adopts MFC framework + GDI graphics programming + SQL database programming + COM components.

[0095] The overall idea of ​​the transformer core section optimization algorithm based on dynamic programming is: first, summarize the core section optimization problem and establish a mathematical model; second, determine the set elements of optional sheet widths for core section optimization calculation; finally, determine the recursive formula and decompose the original problem into sub-problems.

[0096] 1) Establish a mathematical model for the optimization problem

[0097] Core cross-section structure diagram Figure 1 , under a given core diameter D (radius R), according to the requirements of the transformer design structure, the width W of each level i The thickness of each sheet is h, which is a multiple of 10 and cannot exceed the range of the core diameter D after stacking. i is an integer, the target level number M, the minimum level width W M is a fixed value.

[0098] Since the width of the core main sheet W1 < the core diameter D, the set of all optional sheet widths can be obtained (W M ~W1, are multiples of 10, increasing in steps of 10), then the problem is transformed into selecting M slice widths from the slice width set, and satisfying the following mathematical description:

[0099] h i =H i –H i-1 , 1≤i≤M

[0100] H0=0

[0101] W i 2 +H i 2 ≤R 2 i∈[1,M]

[0102] Among them, M is the target level, h i is the thickness of the i-th level, H i is the total stack thickness of the i-th level, W iis the width of the i-th level, W i is a multiple of 10, and R is the radius of the iron core.

[0103] 2) Determine the elements of the set of optional sheet widths

[0104] The relationships between the number of sheet widths count, the sheet width, and the corresponding total stack thickness in the set of optional sheet widths are as follows:

[0105]

[0106]

[0107]

[0108] Among them, count represents the number of sheet widths, W i is the width of the i-th level, H i is the total stack thickness of the i-th level, R is the radius of the iron core, W M is the width of the smallest level.

[0109] For an iron core with a diameter D = 662 mm (R = 331 mm), if the required number of levels is 18 and the width of the smallest level is 270 mm, then in the set of optional sheet widths, count = 39 types, and the sheet widths and the corresponding total stack thicknesses are shown in Table 1:

[0110] Table 1 Sheet widths and corresponding total stack thickness table

[0111] Serial number Sheet width W Total stack thickness H Serial number Sheet width W Total stack thickness H Serial number Sheet width W Total stack thickness H Serial number Sheet width W Total stack thickness H 1 650 62 11 550 184 21 450 242 31 350 280 2 640 84 12 540 191 22 440 247 32 340 284 3 630 101 13 530 198 23 430 251 33 330 286 4 620 116 14 520 204 24 420 255 34 320 289 5 610 128 15 510 211 25 410 259 35 310 292 6 600 139 16 500 216 26 400 263 36 300 295 7 590 150 17 490 222 27 390 267 37 290 297 8 580 159 18 480 227 28 380 271 38 280 299 9 570 168 19 470 233 29 370 274 39 270 302 10 560 176 20 460 238 30 360 277

[0112] 3) Establish a dynamic programming recurrence formula

[0113] According to the characteristics of solving optimization problems by the dynamic programming algorithm, establish a dynamic programming recurrence formula:

[0114] [[ID=4�]]

[0115] Among them, lt and rt are the subscripts in the sheet width set array, 0 ≤ lt < r ≤ count, ct is the number of levels to be taken out from the sheet width set array, W rt is the sheet width with the subscript rt in the sheet width set array, H rt is for W rt the total stack thickness corresponding to the sheet width, H lt is the total stack thickness corresponding to the sheet width with the subscript lt in the sheet width set array, m is the recursive variable for the number of levels taken out, and l is the recursive variable for the subscript selection.

[0116] In the method of the present invention, the functional formula for calculating the optimal result of the iron core cross-section is f(0, count, M). The embodiment is f(0, 19, 18), and the optimal result is calculated as shown in Table 2.

[0117] Table 2 Core Optimization Results

[0118]

[0119] The optimal total area on one side is 163300mm 2 , then the optimal total area of ​​the core is 326600mm 2 .

[0120] The above description is only an embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modification, equivalent replacement, improvement, expansion, etc. made within the spirit and principle of the present invention are included in the scope of protection of the present invention.

Claims

1. A transformer core cross-section optimization method based on dynamic programming, characterized in that: The following steps are involved: 1) Input the given core diameter and parameter data, and establish the mathematical model of the transformer core cross section according to the transformer core design structure; 2) Obtaining a set of optional core widths based on the established mathematical model of the transformer core cross section; 3) Based on the set of optional core widths, a dynamic programming recursive formula is established to obtain the optimal transformer core cross-section; 4) Visualize the optimal result of the transformer core cross-section and determine whether it meets the requirements. If so, export the corresponding document data and upload it to the database for storage; if not, return to step 1).

2. The method for optimizing transformer core cross-section based on dynamic programming according to claim 1, characterized in that: The transformer core design structure is specifically as follows: the width of each stage is W i The thickness of each sheet is h, and the thickness of each sheet is h. i is an integer, the target level number M, the minimum level width W M is a fixed value.

3. The method for optimizing transformer core cross-section based on dynamic programming according to claim 1, characterized in that: In step 1), the mathematical model of the transformer core cross section is established as follows: The width of the core main sheet W1 < the core diameter D, and the set of all optional sheet widths is obtained, namely: W M ~W1, width of each level W i are all multiples of 10, increasing in steps of 10; then M slice widths are selected from the slice width set, satisfying the following conditions: h i =H i –H i-1 ,1≤i≤M H0＝0 W i 2 +H i 2 ≤R 2 i∈[1,M] Among them, M is the target level, h i is the thickness of the i-th level, H i is the total stack thickness of the i-th level, W i is the width of the i-th level slice, W i It is a multiple of 10, and R is the core radius.

4. The method for optimizing transformer core cross-section based on dynamic programming according to claim 1, characterized in that: The optional sheet width set includes: sheet width quantity count, sheet width, and corresponding total stack thickness.

5. The method for optimizing transformer core cross-section based on dynamic programming according to claim 1, characterized in that: In step 2), the optional slice width set is obtained, specifically: Get the relationship between the number of slice widths, slice widths, and the corresponding total stacking thickness in the optional slice width set, namely: Among them, count represents the number of slice widths, W i is the width of the i-th level slice, H i is the total stack thickness of the i-th level, R is the core radius, W M The minimum film width.

6. The method for optimizing transformer core cross-section based on dynamic programming according to claim 1, characterized in that: The step 3) is specifically as follows: (1) Solve the optimal result of transformer core cross section according to the dynamic programming algorithm and establish the dynamic programming recursive formula: where, lt and rt are respectively the subscripts in the array of the chip width set, 0 ≤ lt < r ≤ count, ct is the number of levels to be taken out from the array of the chip width set, and W rt is the chip width with the subscript rt in the array of the chip width set, and H rt is the total stacking thickness corresponding to W rt of the chip width, and H lt is the total stacking thickness corresponding to the chip width with the subscript lt in the array of the chip width set, m is the recursive variable of the number of levels taken out, and l is the recursive variable of the subscript selection. (2) According to the dynamic programming recursive formula, the function formula for the optimal result of the core cross section is: f(0,count,M) Where count represents the number of slice widths, and M represents the number of target levels.

7. The method for optimizing transformer core cross-section based on dynamic programming according to claim 6, characterized in that: In the recursive process of the dynamic programming algorithm, there are redundant identical sub-problems. Through the parameter dictionary, the results of the corresponding sub-problems during the execution of the dynamic programming algorithm are cached, and the results of the sub-problems calculated during the recursive process are directly returned to avoid recalculating redundant sub-problems and improve the efficiency of algorithm execution.

8. A transformer core cross-section optimization system based on dynamic programming, characterized in that: include: Main interface unit, data input module, logic operation module, vector graphics drawing module and output and persistence module; The main interface unit is used to visualize the transformer core cross-section optimization process and the optimal result of the transformer core cross-section; The data input module is used to configure the default values ​​of other parameters corresponding to the core diameter. When inputting, only the core diameter is input to read the default values ​​of other parameters, and the obtained data is sent to the logic operation module; The logic operation module is used to read the core diameter and other corresponding parameters sent by the data input module, obtain a set of optional sheet widths based on the established mathematical model of the transformer core cross section, and perform recursive calculations based on the dynamic programming algorithm to obtain the optimal result of the transformer core cross section; The vector graphics drawing module is used to convert the received transformer core cross-section optimal result into graphic information, store it in a graphic set, and visually draw it on the main interface unit and output a CAD file to provide graphic data; The output and persistence module is used for CAD drawing output, transformer core section calculation document storage, and transformer core section data upload to the database.

9. The transformer core cross-section optimization system based on dynamic programming according to claim 8, characterized in that: The main interface unit adopts the MFC framework and performs functional expansion and packaging according to interaction requirements.

10. The transformer core cross-section optimization system based on dynamic programming according to claim 8, characterized in that: The main interface unit includes: a function area, a property bar, a canvas document, and an output bar; Functional area, used to perform functional actions in the optimization process; The attribute column is the attribute table, which is used to enter the parameters related to the calculation of core diameter and core cross section; The canvas document is a canvas area for drawing vector graphics of the core cross section. The vector graphics drawing module displays the graphics set in the canvas document area through GDI graphics programming technology and renders the graphics data through graphic elements. The output column is used to output the optimal results of the transformer core cross-section and display them visually at the corresponding position.

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