CN107658110B - Iron core structure for improving iron core filling rate and shearing and assembling method thereof - Google Patents
Iron core structure for improving iron core filling rate and shearing and assembling method thereof Download PDFInfo
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- CN107658110B CN107658110B CN201710981565.6A CN201710981565A CN107658110B CN 107658110 B CN107658110 B CN 107658110B CN 201710981565 A CN201710981565 A CN 201710981565A CN 107658110 B CN107658110 B CN 107658110B
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- iron core
- section
- shearing
- silicon steel
- core
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 111
- 238000000034 method Methods 0.000 title claims abstract description 33
- 238000010008 shearing Methods 0.000 title claims abstract description 31
- 229910000976 Electrical steel Inorganic materials 0.000 claims abstract description 39
- 238000005096 rolling process Methods 0.000 claims abstract description 10
- 239000000463 material Substances 0.000 claims abstract description 9
- 241000826860 Trapezium Species 0.000 claims description 3
- 238000005520 cutting process Methods 0.000 claims description 3
- 239000011162 core material Substances 0.000 abstract description 38
- 238000003475 lamination Methods 0.000 description 16
- 238000005457 optimization Methods 0.000 description 6
- 229910052742 iron Inorganic materials 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000004364 calculation method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000010030 laminating Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/24—Magnetic cores
- H01F27/26—Fastening parts of the core together; Fastening or mounting the core on casing or support
- H01F27/266—Fastening or mounting the core on casing or support
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/24—Magnetic cores
- H01F27/245—Magnetic cores made from sheets, e.g. grain-oriented
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0206—Manufacturing of magnetic cores by mechanical means
- H01F41/0233—Manufacturing of magnetic circuits made from sheets
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Manufacturing Cores, Coils, And Magnets (AREA)
Abstract
The invention relates to an iron core structure for improving the filling rate of an iron core and a shearing and assembling method thereof, wherein core columns or yokes of the iron core are polygonal sections formed by stacking multi-stage trapezoid section structures, and the lengths of adjacent bottom edges of adjacent two-stage trapezoids in the core column sections or yoke sections are the same; the method comprises the following steps: longitudinally shearing the silicon steel sheet coil stock according to a specified angle with the rolling direction to form a trapezoid stock; transversely shearing the trapezoid materials according to a specified angle and the length of the single silicon steel sheet to form a plurality of single silicon steel sheets; stacking a plurality of single silicon steel sheets into one stage of an iron core, wherein the section of the iron core is trapezoidal; stacking a plurality of stages of different specifications according to the method; the plurality of stages are stacked to form an iron core. The invention adopts the single-stage iron core section with the trapezoid structure, effectively improves the filling rate of the iron core, can save 20% of iron core materials, reduces the cost, and simultaneously, the three-phase coil is independently wound and then sleeved with the core column part of the three-dimensional stacked iron core, so that the three-phase coil is convenient to stack, reduces the assembly time and improves the tooling efficiency.
Description
Technical Field
The invention relates to an iron core structure optimization technology, in particular to an iron core structure for improving the filling rate of an iron core and a shearing and assembling method thereof.
Background
The iron core is an important component of the power transformer, is not only a magnetic flux loop of the transformer, but also a supporting core of the transformer, the weight of the iron core is more than thirty percent of the total weight of the transformer, and the larger the product is, the larger the proportion is, so that the cost of the iron core has a significant influence on the total manufacturing cost of the transformer. Therefore, an important element in the manufacture of transformers is the design of the core.
The transformer manufacturing industry in China generally adopts standard iron core design drawings in enterprises, and for many years, people are always searching for a shortcut for reducing the cost of an iron core, and the optimization calculation of the section of the iron core is one of important methods for realizing the shortcut. In order to fully utilize the space in the coil, the transformer iron core is usually stacked in a stepped manner, namely, the iron core is formed by stacking a plurality of silicon steel sheets with different widths, the outline of the iron core is circular, and the section of the iron core is in a structure with up-down symmetry in the circle.
Aiming at the problem of optimizing the section of the transformer core, some researchers propose various optimization methods for the section of the transformer core. The Chinese patent (issued publication No. CN 105845427A) proposes a transformer core section design method based on particle swarm optimization, and by adopting the design method, the transformer core design scheme can be rapidly obtained. The Chinese patent (issued publication number CN 101013624) uses an optimized design method for the section of the transformer core, and the calculation of auxiliary tools can greatly reduce the manual labor degree. The Chinese patent (issued publication No. CN 201765913U) proposes a novel iron core column of a power transformer, and the design of an oil duct is increased, so that the heat dissipation performance of the novel iron core column is better, and copper loss and iron loss caused by heating are better reduced. Chinese patent (grant publication No. CN102208274 a) solves the design of the optimal core cross-section by programming. In summary, the above patents all adopt programs to calculate the optimal section of the transformer core, which releases manual solution, improves the calculation speed, but does not substantially improve the section of the core structurally, and does not reach the ideal filling coefficient.
At present, the power transformer iron core generally adopts the same multi-stage rectangular cross-section structure, and the width and thickness of each stage of lamination are generally and uniquely determined by looking up a table after the diameter of the iron core is determined. The effective cross-sectional area of the core directly affects the no-load loss, core diameter, and coil inner diameter. Therefore, the optimization of the section of the iron core can effectively save the manufacturing cost of the transformer, and has important significance. In view of the above-mentioned current situation, from the aspects of material saving and energy saving of product design, it is necessary to provide an iron core section optimization structure and method, which can effectively reduce the cost and no-load loss of the transformer iron core. The technical scheme capable of meeting the requirements is not reported at present.
Disclosure of Invention
Aiming at the defects of low filling rate of the section of the iron core, high manufacturing cost of the iron core, large no-load loss and the like in the prior art, the invention aims to provide an iron core structure for improving the filling rate of the iron core and a shearing and assembling method thereof.
In order to solve the technical problems, the invention adopts the following technical scheme:
according to the iron core structure for improving the filling rate of the iron core, the core column or the yoke of the iron core is of a polygonal section formed by stacking multiple stages of trapezoid section structures, and the lengths of adjacent bottom edges of two adjacent stages of trapezoids in the core column section or the yoke section are the same.
The multi-stage trapezoid cross-section structures are stacked in parallel.
Each stage of trapezoid section is of an integral structure or a spliced structure.
The multi-stage trapezoid cross-section structure is divided into two parts, and all the parts are symmetrically spliced into an integral iron core after being stacked in parallel.
The cross section of the limb or yoke of the core also has a rectangular shape, which together with the trapezium forms the cross section of the limb or yoke.
The invention relates to an iron core shearing and assembling method for improving the filling rate of an iron core, which comprises the following steps:
longitudinally shearing the silicon steel sheet coil stock according to a specified angle with the rolling direction to form a trapezoid stock;
transversely shearing the trapezoid materials according to a specified angle and the length of the single silicon steel sheet to form a plurality of single silicon steel sheets;
stacking a plurality of single silicon steel sheets into one stage of an iron core, wherein the section of the iron core is trapezoidal;
stacking a plurality of stages of different specifications according to the method;
the plurality of stages are stacked to form an iron core.
The cutting angle of the silicon steel sheet is not more than 3 degrees with the rolling direction of the silicon steel sheet, and the transverse shearing adopts a positive and negative knife alternate shearing mode with the rolling direction of the silicon steel sheet being 40-50 degrees.
The core column and the yoke of the iron core after being stacked form a polygonal cross section, and the overall shape of the cross section of the iron core respectively meets the requirements of any shape of the cross section of the main column, the side column, the upper yoke and the lower yoke.
The invention has the following beneficial effects and advantages:
1. compared with the three-phase three-dimensional coiled iron core with the same capacity, the invention adopts the single-stage iron core section with the trapezoid structure, effectively improves the filling rate of the iron core, is verified to save 20% of iron core materials and reduce the cost, simultaneously, the three-phase coil can be independently wound, sleeved with the core column part of the three-dimensional stacked iron core after winding is completed, and then the yoke is stacked and inserted, so that the stacking is convenient, the assembly time is shortened, and the tooling efficiency is improved.
2. The method for optimizing the opening of the iron core increases the number of stages of the iron core, but the total lamination number is unchanged, the workload is not increased for lamination, the lamination difficulty is reduced, and the transformer iron core which meets the technological requirements is easier to process.
3. The invention adopts a lamination mode to assemble the iron core, and can independently wind the coil, so that the coil structure is more compact, and the short circuit resistance is enhanced.
Drawings
Fig. 1 is a schematic diagram of a longitudinal shearing and blanking structure of an iron core of the invention;
fig. 2 is a schematic diagram of a transverse shearing and blanking structure of an iron core according to the invention;
fig. 3A is a schematic view of a first lamination structure of a core leg cross-section according to the present invention;
fig. 3B is a schematic view of a second lamination configuration of a core leg cross-section according to the present invention;
fig. 3C is a schematic view of a third lamination configuration of a core leg cross-section according to the present invention;
fig. 4A is a schematic view of a first lamination structure of a core leg cross-section of the present invention;
fig. 4B is a schematic view of a second lamination stack of a core leg cross-section of the present invention;
fig. 5A is a schematic view of a first lamination structure of the upper and lower yoke sections of the core of the present invention;
fig. 5B is a schematic view of a second lamination structure of the upper and lower yoke sections of the core of the present invention;
fig. 5C is a schematic view of a third lamination structure of the cross section of the upper and lower yokes of the core according to the present invention;
fig. 5D is a schematic view of a fourth lamination structure of the cross section of the upper and lower yokes of the core according to the invention;
fig. 5E is a schematic view of a fifth lamination structure of the upper and lower yoke sections of the core of the present invention.
Wherein 1 is the section of the iron core column, 2 is the grade, 3 is a single silicon steel sheet, and 4 is a coiled material of the silicon steel sheet.
Detailed Description
The invention is further elucidated below in connection with the drawings of the specification.
According to the iron core structure for improving the filling rate of the iron core, the core column or the yoke of the iron core is of a polygonal section formed by stacking multiple stages of trapezoid section structures, and the lengths of adjacent bottom edges of two adjacent stages of trapezoids in the core column section or the yoke section are the same.
The embodiment provides three structural forms, the first is that the multi-stage trapezoid cross-section structure is stacked in parallel as shown in fig. 3A. The structure is suitable for the main column of the planar stacked iron core.
The second type is shown in fig. 3B, and the multi-stage trapezoidal section structure is divided into two parts, and the parts are symmetrically spliced into an integral iron core column section 1 after being stacked in parallel. The structure is suitable for the main column of the three-phase three-dimensional stacked iron core.
The trapezoid cross section of each stage 2 is of an integral structure, namely a first structure, or a splicing structure, namely a third structure, as shown in fig. 3C, and is applied to a three-phase three-dimensional stacked iron core or a planar stacked iron core, and the one-stage trapezoid in the cross section of the iron core is formed by randomly splicing two or more trapezoids. In actual operation, if the width of the stored coiled silicon steel sheet material 4 is smaller than the design width, the mode can be adopted for splicing, so that the purpose of obtaining local materials is achieved.
Each stage of the core limb section 1 is laminated by quadrilateral silicon steel sheets of non-parallel opposite sides, as shown in figure 2.
The invention relates to an iron core shearing and assembling method for improving the filling rate of an iron core, which comprises the following steps:
1) Longitudinally shearing the silicon steel sheet coil stock 4 according to a specified angle with the rolling direction to form a trapezoid material;
2) Transversely shearing the trapezoid materials according to the design angle and the length of the single silicon steel sheet to form a plurality of single silicon steel sheets 3;
3) Stacking a plurality of single silicon steel sheets 3 into one stage 2 of the section 1 of the iron core column, wherein the section is trapezoid;
4) Stacking a plurality of stages 2 of different specifications according to the above method;
5) The multiple stages 2 are stacked to form a core limb cross-section 1.
In the step 1), the longitudinal shearing cutting angle of the silicon steel sheet and the rolling direction of the silicon steel sheet are not more than 3 degrees, and a specific embodiment is 0.8 degree, as shown in fig. 1.
In the step 2), the transverse shearing is realized in a mode of alternately shearing with a positive and negative cutter with the rolling direction of the silicon steel sheet being 40-50 degrees, and the sheared single silicon steel sheet 3 forms a trapezoid, and the silicon steel sheet is not bent, as shown in fig. 2.
In the step 3), the sheared single silicon steel sheet 3 is laminated to form a first stage 2, the cross section of the single silicon steel sheet is trapezoidal, and the single silicon steel sheet is laminated and assembled to form an inscribed polygonal structure of a circular (shown in fig. 3A-3C), an ellipse (shown in fig. 4A) or a runway (shown in fig. 4B) arc part.
In step 5), stacking a plurality of stages into one core limb section 1 is achieved by:
punching a positioning hole at the center line of each single silicon steel sheet 3;
placing a positioning rod on the iron core stacking table;
each single silicon steel sheet 3 passes through the silicon steel sheet positioning holes through the positioning rods to position and stack the silicon steel sheets.
The section 1 of the iron core post after the lamination forms a cross section with an inscribed trapezoid, and the overall shape of the cross section of the iron core respectively meets the requirements of any shapes of the sections of the main post, the side post and the upper and lower yokes.
If the iron yoke is applied to a three-phase three-dimensional laminated iron core, the cross section of the iron yoke is formed by laminating a plurality of trapezoids to form an approximate sector (as shown in fig. 5A), wherein the arc part of the approximate sector is an inscribed polygon of an arc, and the rest part of the approximate sector is formed by laminating isosceles trapezoid cross sections.
Or, the cross section of the iron yoke is a pressed yoke structure which is formed by stacking a plurality of trapezoids to form an approximate triangle (as shown in fig. 5B) and is applied to the three-phase three-dimensional stacked iron core.
Or, the cross section of the iron yoke is a half-elliptic (shown in fig. 5C) semicircular (shown in fig. 5D) or flat-topped semicircular (shown in fig. 5E) press yoke structure formed by stacking a plurality of trapezoids, the cross section of the flat-topped part is rectangular, and the cross section of the circular arc part is trapezium, so that the cross section of the core column or the yoke is formed together.
The arc portions of the above-described shape cross section each employ the stage 2 of the trapezoid cross section in the present invention.
Claims (7)
1. The iron core shearing and assembling method for improving the filling rate of the iron core is characterized by comprising the following steps of:
longitudinally shearing the silicon steel sheet coil stock according to a specified angle with the rolling direction to form a trapezoid stock;
transversely shearing the trapezoid materials according to a specified angle and the length of the single silicon steel sheet to form a plurality of single silicon steel sheets;
stacking a plurality of single silicon steel sheets into one stage of an iron core, wherein the section of the iron core is trapezoidal;
stacking a plurality of stages of different specifications according to the method;
a plurality of stages are stacked to form an iron core;
wherein, improve the iron core structure of iron core filling rate and be: the core column or the yoke of the iron core is of a polygonal section formed by stacking multiple stages of trapezoid section structures, and the lengths of adjacent bottom edges of two adjacent stages of trapezoids in the core column section or the yoke section are the same.
2. The method for shearing and assembling the iron core for improving the filling rate of the iron core according to claim 1, wherein the method comprises the following steps: the cutting angle of the silicon steel sheet is not more than 3 degrees with the rolling direction of the silicon steel sheet, and the transverse shearing adopts a positive and negative knife alternate shearing mode with the rolling direction of the silicon steel sheet being 40-50 degrees.
3. The method for shearing and assembling the iron core for improving the filling rate of the iron core according to claim 1, wherein the method comprises the following steps: the core column and the yoke of the iron core after being stacked form a polygonal cross section, and the overall shape of the cross section of the iron core respectively meets the requirements of any shape of the cross section of the main column, the side column, the upper yoke and the lower yoke.
4. The method for shearing and assembling the iron core for improving the filling rate of the iron core according to claim 1, wherein the method comprises the following steps: the multi-stage trapezoid cross-section structures are stacked in parallel.
5. The method for shearing and assembling the iron core for improving the filling rate of the iron core according to claim 4, wherein the method comprises the following steps: each stage of trapezoid section is of an integral structure or a spliced structure.
6. The method for shearing and assembling the iron core for improving the filling rate of the iron core according to claim 1, wherein the method comprises the following steps: the multi-stage trapezoid cross-section structure is divided into two parts, and all the parts are symmetrically spliced into an integral iron core after being stacked in parallel.
7. The method for shearing and assembling the iron core for improving the filling rate of the iron core according to claim 1, wherein the method comprises the following steps: the cross section of the limb or yoke of the core also has a rectangular shape, which together with the trapezium forms the cross section of the limb or yoke.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710981565.6A CN107658110B (en) | 2017-10-20 | 2017-10-20 | Iron core structure for improving iron core filling rate and shearing and assembling method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710981565.6A CN107658110B (en) | 2017-10-20 | 2017-10-20 | Iron core structure for improving iron core filling rate and shearing and assembling method thereof |
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| Publication Number | Publication Date |
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| CN107658110A CN107658110A (en) | 2018-02-02 |
| CN107658110B true CN107658110B (en) | 2024-03-12 |
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108847347A (en) * | 2018-08-03 | 2018-11-20 | 青岛云路先进材料技术有限公司 | A kind of method of the continuous sawing sheet of amorphous band and a kind of multistage material strip |
| CN109346289B (en) * | 2018-11-09 | 2021-11-16 | 王永法 | Transformer laminated core and preparation method thereof |
| CN109887739B (en) * | 2019-03-29 | 2021-03-02 | 中变集团上海变压器有限公司 | Method for manufacturing transformer iron core |
| CN114927338B (en) * | 2022-05-31 | 2024-04-09 | 金三角电力科技股份有限公司 | Secondary belt-dividing tapping machine for three-dimensional iron core silicon steel belt and processing technology |
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|---|---|---|---|---|
| FR1308463A (en) * | 1961-12-22 | 1962-11-03 | Thomson Houston Comp Francaise | Improvements in the manufacture of magnetic cores |
| US4136322A (en) * | 1975-12-05 | 1979-01-23 | Hitachi, Ltd. | Single-phase three-legged core for core type transformer |
| US4140987A (en) * | 1975-12-12 | 1979-02-20 | Hitachi, Ltd. | Core of a core-type transformer |
| CN201812661U (en) * | 2010-07-26 | 2011-04-27 | 周尧达 | Inductance ballast for high-intensity gas discharge lamp |
| CN207611666U (en) * | 2017-10-20 | 2018-07-13 | 特变电工股份有限公司 | A kind of core structure improving iron core filling rate |
-
2017
- 2017-10-20 CN CN201710981565.6A patent/CN107658110B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1308463A (en) * | 1961-12-22 | 1962-11-03 | Thomson Houston Comp Francaise | Improvements in the manufacture of magnetic cores |
| US4136322A (en) * | 1975-12-05 | 1979-01-23 | Hitachi, Ltd. | Single-phase three-legged core for core type transformer |
| US4140987A (en) * | 1975-12-12 | 1979-02-20 | Hitachi, Ltd. | Core of a core-type transformer |
| CN201812661U (en) * | 2010-07-26 | 2011-04-27 | 周尧达 | Inductance ballast for high-intensity gas discharge lamp |
| CN207611666U (en) * | 2017-10-20 | 2018-07-13 | 特变电工股份有限公司 | A kind of core structure improving iron core filling rate |
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| CN107658110A (en) | 2018-02-02 |
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