CN215496320U - Three-phase three-dimensional iron core - Google Patents

Abstract

The utility model belongs to the technical field of transformer equipment, and relates to a three-phase three-dimensional iron core which comprises three iron core frames with the same structure, wherein each iron core frame comprises two iron core side columns, and after the joint surfaces of the two adjacent iron core side columns are connected in an involutory manner, an iron core column is formed and is used for sleeving a coil; the two ends of the long shaft of the iron core column are respectively provided with long shaft arcs, the two ends of the short shaft of the iron core column are respectively provided with short shaft arcs, and the adjacent long shaft arcs and the short shaft arcs are connected through straight edges. The iron core is of a four-arc four-line section structure which is three-dimensionally arranged in a triangle, and four straight lines of the four-arc four-line section are parallel to tangent lines of two adjacent coils which are arranged in the triangle and form an included angle of 120 degrees with each other, so that the duty factor of the iron core and the coils of the three-phase three-dimensional transformer is minimum, and the material consumption of the transformer is greatly reduced.

Description

Three-phase three-dimensional iron core

Technical Field

The utility model belongs to the technical field of transformer equipment, and relates to a three-phase three-dimensional iron core.

Background

The power transformer product with 1-level energy consumption is produced according with the energy efficiency limit value and the energy efficiency grade standard of the power transformer in accordance with the national standard GB 20052-2020,

at present, the best silicon steel material at home and abroad and a conventional manufacturing method are adopted, so that the zero deviation target is difficult to realize, and the manufacturing cost is high and is difficult to be accepted by users; the product performance, reliability and stability of the amorphous alloy material are also relatively problematic. Therefore, a new transformer structure or a new process method is urgently needed to be found so as to comprehensively popularize low-energy-consumption products.

Compared with a planar transformer, the triangular arrangement of the iron core and the coil of the three-phase three-dimensional transformer effectively reduces the length of the iron yoke, so that the performance and the cost performance of the transformer are greatly improved. However, the iron core of the conventional three-phase three-dimensional transformer is formed by combining three iron core frames in pairs into three complete iron core columns with circular cross sections. The section of each iron core frame is half of that of the round iron core. The width of the section of a single iron core frame from the inner side to the outer side is from small to large to small, the maximum width is only 0.565 times of the diameter of the iron core, the width of most of the section is less than half of the diameter of the iron core, and the height of the lamination of the section of the iron core frame is more than 1.7 times of the maximum width, so that the difference of the inner magnetic path and the outer magnetic path of each iron core frame is large, and the average magnetic path length of the iron core frames is increased. Compared with a round iron core with the same section, the four-arc four-line section adopted by the utility model has better magnetic performance. When the cross section of the iron core is not changed, the width of the iron core sheet is increased, the stacking thickness is reduced, the length of the iron yoke is reduced, the length of a magnetic circuit of the iron core frame is greatly shortened compared with that of a three-dimensional circular cross section, and the weight of the iron core is greatly reduced. On the other hand, the lamination thickness of the four-arc four-line iron core is reduced, the magnetic flux distribution of the inner layer and the outer layer of the iron core is improved, and the iron loss additional coefficient is also gradually reduced along with the increase of the length/short axis ratio of the cross section of the four-arc four-line iron core, so that the magnetic density of the four-arc four-line iron core can be improved under the condition of a certain length/short axis ratio value, but the iron loss is not increased. If the iron core and the coil of the transformer are further optimally designed, the manufacturing cost of the four-arc four-wire section transformer with the proper length/short shaft ratio is selected to be reduced by more than 10-15% compared with the manufacturing cost of a transformer with a circular section. The cross section of the four-arc four-line iron core frame is also beneficial to strengthening the painting and curing of the amorphous alloy and the overall strength of the amorphous alloy. The Chinese invention patent ZL201310218155.8 discloses a structure of an open type three-dimensional triangular rolled iron core, and the iron core disclosed by the patent adopts an open design, so that the iron core can be effectively and conveniently sleeved, but the problem of large iron core loss exists.

Disclosure of Invention

Aiming at the problems, the utility model provides a three-phase three-dimensional iron core which adopts a four-arc four-wire section structure iron core with a triangular three-dimensional arrangement, and because four straight lines of the four-arc four-wire section are parallel to the tangent line of two adjacent coils in the triangular arrangement and form an included angle of 120 degrees with each other, the space factor of the three-phase three-dimensional transformer iron core and the coils is minimum, and the material consumption of the transformer is greatly reduced.

According to the technical scheme of the utility model: the utility model provides a three-phase three-dimensional iron core, includes the same iron core frame of three structure, every the iron core frame all includes two iron core side columns, its characterized in that: after the joint surfaces of two adjacent iron core side columns are involutively connected, an iron core column is formed for sleeving a coil;

the two ends of the long shaft of the iron core column are respectively provided with long shaft arcs, the two ends of the short shaft of the iron core column are respectively provided with short shaft arcs, and the adjacent long shaft arcs and the short shaft arcs are connected through straight edges.

As a further improvement of the utility model, the straight sides are tangentially connected with the corresponding long-axis circular arcs and short-axis circular arcs.

As a further improvement of the present invention, the central angle of the long axis arc is 120 degrees, and the central angle of the short axis arc is 60 degrees.

As a further improvement of the utility model, the iron core side column is formed by stacking a plurality of silicon steel sheets which are arranged in parallel, and one end point of the silicon steel sheet and one end point of the long-axis arc are parallel to the end point connecting line of the short-axis arc which is adjacent to the silicon steel sheet.

As a further improvement of the utility model, a process notch is formed at one end of the iron core side column corresponding to the shortest silicon steel sheet.

The utility model has the technical effects that: the product of the utility model has simple, reasonable and ingenious structure, adopts a four-arc four-line cross section formed by connecting an upper large arc with 60 degrees, a left small arc with 120 degrees and a right small arc with four straight lines, the value of the long shaft/short shaft ratio can be randomly selected within the range of 1.0-1.8, the periphery of the four-arc four-line cross section is smooth and mellow, the winding is easy when a coil is wound, and the setting is convenient and reliable.

Drawings

FIG. 1 is a schematic cross-sectional view of the present invention.

Fig. 2 is a schematic cross-sectional view of a core limb.

Fig. 3 is an assembly view of the core and the coil.

Fig. 4 is a perspective view of the present invention.

Detailed Description

The following further describes embodiments of the present invention with reference to the drawings.

Fig. 1 to 3 include an iron core frame 100, an iron core side column 110, a long axis arc 111, a straight edge 112, a short axis arc 113, a process notch 114, a coil 200, a coil 300, a case 400, and the like.

As shown in fig. 1 to 3, the present invention is a three-phase three-dimensional iron core, including three iron core frames 100 with the same structure, each of the iron core frames 100 includes two iron core side columns 110, and the joint surfaces of two adjacent iron core side columns 110 are connected in an involutory manner to form an iron core column for sleeving a coil 300. The two ends of the long axis of the core limb are respectively marked as C, D, and the two ends of the short axis of the core limb are respectively marked as A, B.

The two ends of the long axis of the core limb are respectively provided with a long axis arc 111, the two ends of the short axis of the core limb are respectively provided with a short axis arc 113, and the adjacent long axis arcs 111 and the short axis arcs 113 are connected through a straight edge 112.

The straight edge 112 is connected tangentially to the corresponding major axis arc 111 and minor axis arc 113.

The major axis arc 111 has a central angle of 120 degrees and the minor axis arc 113 has a central angle of 60 degrees.

The iron core side column 110 is formed by stacking a plurality of silicon steel sheets which are arranged in parallel, one end point of the silicon steel sheet and the long axis arc 111 is parallel to an end point connecting line of the short axis arc 113 which is adjacent to the end point connecting line, and a process notch 114 is formed at one end of the iron core side column 110 corresponding to the shortest silicon steel sheet.

As shown in FIGS. 1-3, the value of the major axis/minor axis ratio K is defined to achieve the reasonable and optimal electrical performance and the best cost performance. The four-arc four-line cross section structure can reduce the material grade of iron core materials with the same performance requirement by more than 2, and solves the problems of difficult manufacture and low cost performance of the materials with the energy consumption standard of level 1 in the GB 20052-2020 power transformer energy efficiency limit value and the energy efficiency grade standard which are produced by domestic and foreign raw materials at present.

The utility model adopts the broken yoke structure, so that the iron core and the coil are manufactured separately, the trouble that the coil needs to be wound on the formed iron core for the closed round section wound iron core coil can be overcome, the process gap and the insulation interval of the product are reduced, the transformer coil can be manufactured by adopting advanced processes such as graded insulation, a half oil duct and the like, the product cost is further reduced, and the batch production can be carried out by adopting the conventional transformer manufacturing process.

The four-arc four-line section of the utility model is not only suitable for three-phase folding type three-dimensional wound core transformers made of silicon steel sheet materials, but also suitable for three-phase broken yoke type amorphous alloy wound core transformers. Because the length of the 1 st bottom edge M1=1.732 (k-1) × a at the inner side of the four-arc four-line section iron core frame is related to the k value, the k value of the 1 st bottom edge M1 is generally optimally designed to be 1.3-1.6, the width of the initial sheet of the iron core inner frame can be greatly increased, the width of the inner side of the iron core frame is greatly increased, the section of the amorphous alloy iron core is in a pyramid shape, the strength of the amorphous alloy iron core can be greatly increased after the end face is painted and cured, and the overall rigidity and the suspension strength of the amorphous alloy iron core are greatly improved, so that the stability of the magnetic performance of the amorphous alloy iron core can be solved, and the magnetic performance of the amorphous alloy iron core is improved.

The utility model is suitable for three-phase three-dimensional oil-immersed transformers, epoxy casting and wire-wound dry-type transformers. The three-phase three-dimensional transformer can be used for manufacturing power transformer products with the capacity from several KVA to more than 1 ten thousand KVA.

As shown in fig. 1 to 3, the present invention can adopt iron-based amorphous alloy strips and various silicon steel sheet materials, and the manufacturing method of the sheet materials is the same as that of the conventional three-dimensional wound iron core.

Designing and calculating the four-arc four-wire section iron core: as shown in fig. 2 below, the four-arc four-line cross-section is defined as: if the minor semi-axis of the four-arc four-line cross section is a, the major semi-axis is b, b/a is k, b = ka, the intersection point of the major axis and the minor axis is O, in the minor axis direction, the O is taken as the center of a circle, a is taken as the upper and lower 60-degree arcs of the radius, OO1=2 (k-1) a = c is taken in the major axis direction, r = (2-k) a is taken as the center of a circle, the left and right 120-degree arcs of the radius are taken in the major axis direction, and the cross section within the range of the connection line of the two arc points is the defined four-arc four-line cross section. The angle formed by the extension lines of the line segments formed by the connecting lines of the two arc points is 120 degrees, so that the three iron cores can be opposite to each other when arranged into a triangle, the magnetic circuits of the iron cores can be shorter, and the iron weight can be effectively reduced. Half of the four-arc four-line section is decomposed into 6 quadrilateral sections, and the bottom edges of the four quadrilateral sections are parallel to symmetrical shafts which are tangent to three coils of the three-dimensional transformer and form an included angle of 120 degrees with each other. Wherein the connecting line of the end points of the two circular arcs of the four-arc four-line section near the symmetry axis is defined as the 1 st base line M1. The vertex of the connecting short shaft is a 2 nd bottom edge M2, the vertex of the connecting long shaft is a 3 rd bottom edge M3, the 4 th bottom edge passing through the center of the small arc is M4, and the two arc end points of the other side of the two arcs passing through the oblate are respectively a 5 th bottom edge M5, a 6 th bottom edge M6 and a minimum top edge width of M7 which are set. Since the bottom side is set at a specific position, the magnitude of the M value can be expressed by a mathematical expression. The side length M of each bottom edge is calculated as follows:

as can be seen from fig. 2: the four-arc four-line cross section has a minor semi-axis a and a major semi-axis ka, the radii R = a of 60 degrees respectively above and below the major arc, the minor arc R = (2-k) × a, and the distance between two circle centers c =2 × (k-1) × a, then:

the widths of the chips in each stage are as follows:

M1=1.732*(k-1)*a，

M2=(1.732*k-1.232+((2-k)^2-(1.866-k)^2)^0.5)*a，

M3=1.1547*k*a，

M4=(1.3094k-0.3094)*a。

M5=(1.732*k-1.1548)*a ,

M6=0.5774*a ,

m7= minimum chip width setting.

The height of each level of the trapezoid is as follows:

H1=0.134*a ，

H2=(0.866-0.5k)*a ,

H3=0.5*r=0.5*(2-k)*a ,

H4=0.5*(2-k)*a ,

H5=1.5*(k-1)*a ,

H6=H7-H8

H7=0.3667*a ,

H8=M7*0.635 .

the apparent section S values of the trapezoids are as follows:

S1=(M1+M2)/2*H1 ,

S2=(M2+M3)/2*H2 ,

S3=(M3+M4)/2*H3 ,

S4=(M4+M5)/2*H4 ,

S5=(M5+M6)/2*H5 ,

S6=(M6+M7)/2*H6 ,

the apparent section of the four-arc four-line shape S = S1+ S2+ S3+ S4+ S5+ S6.

If the window height and the window width of the core frame are known, the core weight can be calculated by a conventional method.

Note that: since the values of the bottom M are set at specific positions, there is a possibility that the calculated H value and the section S value will have a "-" value when the k values are different, which has no influence on the calculation result. This is caused by the fact that the position of the lower base exceeds the position of the upper base.

The outer circumference of the cross section of the four-arc four-wire iron core is Lo = 4M 1+2 a/3 (2-K) a = (3.544+ 2.7392) a.

Since the linear portion 4 × M1 of the circumferential length of the coil surrounding the core has a constant length in the core cross section, the outer circumferential length is Ld = Lo +2 × l d when the coil thickness is d. If half oil ducts are adopted in the coil, no oil duct is arranged in the length of 2 × M1 and the large arc length of 60 degrees at the inner side, and the oil ducts can be arranged in the length of 2 × M1 and the large arc length of 60 degrees at the outer side and the small arc lengths of 240 degrees at both sides. The minor arc is the major axis arc 111 and the major arc is the minor axis arc 113.

In FIG. 3, it can be seen that: the three-phase three-dimensional four-arc four-line section iron core and coil combined section is in the range of two equilateral triangles with the side length being 1.1547 times of the short half shaft of the coil, and the space occupation area is greatly reduced compared with that of a three-dimensional transformer with a circular section. Due to the fact that the K value of the ratio of the long axis to the short axis is increased, on one hand, the magnetic circuit of the iron core is shortened, iron loss is reduced, but on the other hand, the bottleneck length of the coil is also increased, therefore, for the transformer with the specific structure, the cost performance of the iron core with the four-arc four-line-shaped cross section is better than that of a conventional circular three-dimensional transformer, and the K value exists certainly, so that the cost performance of the transformer with the four-arc four-line-shaped cross section is the best.

Claims (4)

1. The utility model provides a three-phase solid iron core, includes three iron core frame (100) that the structure is the same, every iron core frame (100) all includes two iron core side columns (110), its characterized in that: after the joint surfaces of two adjacent iron core side columns (110) are involuntarily connected, an iron core column is formed to be used for sleeving a coil (300);

two ends of the long axis of the iron core column are respectively provided with a long axis arc (111), two ends of the short axis of the iron core column are respectively provided with a short axis arc (113), and the adjacent long axis arcs (111) and the short axis arcs (113) are connected through straight edges (112).

2. The three-phase solid core according to claim 1, wherein: the straight edge (112) is tangentially connected with the corresponding long-axis arc (111) and short-axis arc (113).

3. The three-phase solid core according to claim 1, wherein: the central angle of the long axis circular arc (111) is 120 degrees, and the central angle of the short axis circular arc (113) is 60 degrees.

4. The three-phase solid core according to claim 1, wherein: the iron core side column (110) is formed by stacking a plurality of silicon steel sheets which are arranged in parallel, and one end point of the silicon steel sheet and the long-axis arc (111) is parallel to the end point connecting line of the short-axis arc (113) which is adjacent to the end point connecting line.

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