CN111477433A

CN111477433A - Folding iron core for dry type transformer

Info

Publication number: CN111477433A
Application number: CN202010478036.6A
Authority: CN
Inventors: 程云怒; 郭泓廷; 皮统政; 邹红; 曹健; 周科; 徐进; 熊必润; 毛国篊
Original assignee: Chongqing Wangbian Electric Group Corp ltd
Current assignee: Chongqing Wangbian Electric Group Corp ltd
Priority date: 2020-05-29
Filing date: 2020-05-29
Publication date: 2020-07-31

Abstract

The invention belongs to the technical field of transformers, and particularly relates to a foldable iron core with a dry-type transformer, which comprises an iron core body, a high-voltage coil and a low-voltage coil, wherein the iron core body is provided with a plurality of iron core slots; the iron core body adopts three-phase three-column structure, and every group iron core includes first iron core frame, second iron core frame and third iron core frame, first iron core frame and second iron core frame shape are the same, and first iron core frame and second iron core frame all are less than third iron core frame, first iron core frame, second iron core frame and third iron core frame are rolled up by the wide silicon steel sheet of two sheets and are formed, the adjacent setting of first iron core frame and second iron core frame just all is wrapped up by third iron core frame, the adjacent limit of third iron core frame and first iron core frame and second iron core frame and the adjacent limit of second first iron core frame and second iron core frame constitute the iron core post respectively, high-voltage coil and low-voltage coil suit are on three iron core post respectively.

Description

Folding iron core for dry type transformer

Technical Field

The invention relates to the technical field of transformers, in particular to a folding iron core with a dry-type transformer.

Background

The transformer is a device for changing alternating voltage by utilizing the principle of electromagnetic induction, and main components of the transformer are a primary coil, a secondary coil and an iron core, and the transformer also comprises a corner. The main functions of the transformer are voltage transformation, current transformation, impedance transformation, isolation, voltage stabilization and the like. Transformers can be classified into dry transformers and oil-immersed transformers. Dry transformers are widely used in local lighting, high-rise buildings, airports, and wharf CNC machinery places, and simply, dry transformers refer to transformers in which the core and windings are not immersed in insulating oil. The iron core of the existing dry-type transformer generally comprises a laminated iron core and a three-dimensional rolled iron core. The laminated iron core product has the defects of large exciting current, large no-load loss, large noise, large volume, large weight, large material consumption, low utilization rate, long production time, low efficiency and the like; the three-dimensional wound core has the defects of unequal processed sheet length, high processing precision, large processing difficulty, large joint, large volume, relatively complex processing technology and the like.

Disclosure of Invention

The invention aims to provide a folding iron core for a dry-type transformer, which has the advantages of excellent electromagnetic performance, small exciting current, low no-load loss and the like.

In order to achieve the above purpose, the basic scheme of the invention is as follows: the folding iron core for the dry type transformer comprises an iron core body, a high-voltage coil and a low-voltage coil; the iron core body adopts three-phase three-column structure, and every group iron core includes first iron core frame, second iron core frame and third iron core frame, first iron core frame and second iron core frame shape are the same, and first iron core frame and second iron core frame all are less than third iron core frame, first iron core frame, second iron core frame and third iron core frame are rolled up by the wide silicon steel sheet of different pieces respectively and are formed, the adjacent setting of first iron core frame and second iron core frame just all is wrapped up by third iron core frame, the adjacent limit of third iron core frame and first iron core frame and second iron core frame and the adjacent limit of second first iron core frame and second iron core frame constitute the iron core post respectively, high-voltage coil and low-voltage coil suit are on three iron core post respectively.

The working principle and the beneficial effects of the basic scheme are that: in this scheme, the iron core body adopts the folded form iron core, and the interval can reduce between coil internal diameter and the iron core, and the coil can adopt half oil duct structure and reduce the centre-to-centre spacing, consequently can reduce iron core and coil weight, reduces iron loss and coil copper loss. The method not only retains all performance advantages of the original closed iron core, but also fuses the traditional plate inserting process, so that the product has maintainability; if unqualified phenomenon is generated in the production process, only the corresponding coil needs to be replaced. Especially for the dry type transformer, a large number of expensive pouring molds are saved, the manufacturing cost is reduced, and a large amount of time is saved.

Further, the iron core body cross section is two rectangle butt joint structures. The cross section of the iron core body is of a two-rectangle splicing structure, so that the iron core body is convenient to manufacture, and the iron core body is convenient to install on a transformer.

Furthermore, the butt joint ports of the silicon steel sheets are arranged in the middle of the bottoms of the first iron core frame/the second iron core frame/the third iron core frame. Therefore, the manufacturing of the iron core is convenient, the distance between the iron core frames can be reduced, and no load is reduced.

Furthermore, the cross section of the iron core body is provided with a bevel. The iron core body has the advantages of small no-load current, small harmonic wave of the no-load current, great noise reduction, strong over-excitation capability and the like.

Further, the gap between the first iron core frame and the second iron core frame/the third iron core frame is less than 4 mm. The smaller the gap of the transformer is, the magnetic leakage area of the iron core can be reduced, the noise is reduced, and the no-load loss is reduced; the filling factor of the iron core is improved, so that the size of the coil is reduced, and the iron core material and the coil material are saved.

Further, the gap between the first iron core frame and the second iron core frame/the third iron core frame is less than 2 mm. The smaller the gap of the transformer is, the magnetic leakage area of the iron core can be reduced, the noise is reduced, and the no-load loss is reduced; the filling factor of the iron core is improved, so that the size of the coil is reduced, and the iron core material and the coil material are saved.

Furthermore, steps are also arranged; the step length of each step is more than 5 mm. The step length of each step is larger than 5mm, so that the number of iron chip types is reduced, and the processing is convenient.

Furthermore, the novel steel plate structure also comprises a step joint, the number of steps of the step joint is not less than 5, and the thickness between adjacent layers is not more than 0.015 mm. Thus, the filling coefficient can be improved, the utilization rate of the iron core is improved, and the sectional area is increased.

Further, the length of the step seam from the corner is more than 10 mm. The corner is more than 10mm, so that the processing is convenient, the curvature radius of the iron core is too small when the corner is less than 10mm, and the iron core piece is damaged. This reduces damage to the core.

Further, the angle of the break angle is 135 °. The angle of the bevel is set to be 135 degrees, the internal stress of the damaged silicon steel sheet is 10 percent, and the electromagnetic performance is better compared with that of a round corner.

The folding iron core for the dry-type transformer has the advantages of excellent electromagnetic performance, small exciting current, low no-load loss, low noise, small size, light weight, environmental friendliness, energy conservation, flexible iron core manufacturing, high quality reliability, small appearance size and the like, and can meet the requirements of clients on any size. And the manufacturing cost is greatly reduced when the special iron core winding machine with various specifications, the iron core winding machine with the iron core wire winding and a large number of moulds are not needed.

Drawings

Fig. 1 is a front view of an embodiment of a folded core for a dry-type transformer according to the present invention;

fig. 2 is a sectional view a-a of fig. 1 of the present invention.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: the iron core comprises an iron core body 1, a first iron core frame 2, a second iron core frame 3, a third iron core frame 4 and a silicon steel sheet 5.

This embodiment is substantially as shown in figures 1 and 2 of the accompanying drawings: the folding iron core for the dry type transformer comprises an iron core body 1, a high-voltage coil and a low-voltage coil; the iron core body 1 adopts a three-phase three-column structure, each group of iron cores comprises a first iron core frame 2, a second iron core frame 3 and a third iron core frame 4, the first iron core frame 2 and the second iron core frame 3 are identical in shape, the first iron core frame 2 and the second iron core frame 3 are smaller than the third iron core frame 4, the first iron core frame 2, the second iron core frame 3 and the third iron core frame 4 are formed by rolling two wide silicon steel sheets 5, the first iron core frame and the second iron core frame are adjacently arranged and are all wrapped by the third iron core frame, the third iron core frame and the edges adjacent to the first iron core frame and the second iron core frame and the edges adjacent to the second iron core frame respectively form iron core columns, and a high-voltage coil and a low-voltage coil are respectively sleeved on the three iron core columns (a high-voltage coil and a low-voltage coil are not drawn in the figure). The cross section of the iron core body 1 is provided with a break angle, and the angle of the break angle is 135 degrees. The iron core body 1 has the advantages of small no-load current, small harmonic wave of the no-load current, great noise reduction, strong over-excitation capability and the like. The clearance between the first iron core frame 2/the second iron core frame 3/the third iron core frame 4 is less than 2 mm.

The step length of each step is more than 5 mm. The step number of the step joint is not less than 5, and the adjacent layers are not more than 0.015 mm. The length of the seam from the corner is more than 10 mm.

The cross section of the iron core body 1 is of two rectangular splicing structures. The cross section of the iron core body 1 is of a two-rectangle splicing structure, so that the iron core body 1 is convenient to manufacture, and the iron core body 1 is convenient to install on a transformer.

The butt joints of the silicon steel sheets 5 are arranged in the middle of the bottoms of the first iron core frame 2, the second iron core frame 3 and the third iron core frame 4. Therefore, the manufacturing of the iron core is convenient, the distance between the iron core frames can be reduced, and no load is reduced.

In this scheme, iron core body 1 adopts the European folding type iron core, and the coil internal diameter can reduce with the interval between the iron core, and the coil can adopt half oil duct structure and reduce the centre-to-centre spacing, consequently can reduce iron core and coil weight, reduces iron loss and coil copper loss. The method not only retains all performance advantages of the original closed iron core, but also fuses the traditional plate inserting process, so that the product has maintainability; if unqualified phenomenon is generated in the production process, only the response coil needs to be replaced. Especially for the dry type transformer, a large number of expensive pouring molds are saved, the manufacturing cost is reduced, and a large amount of time is saved. The folding iron core for the dry-type transformer has the advantages of excellent electromagnetic performance, small exciting current, low no-load loss, low noise, small size, light weight, environmental friendliness, energy conservation, flexible iron core manufacturing, high quality reliability, small appearance size and the like, and can meet the requirements of clients on any size.

The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. The folding iron core for the dry type transformer comprises an iron core body, a high-voltage coil and a low-voltage coil; the iron core body adopts three-phase three-column structure, its characterized in that: every group iron core includes first iron core frame, second iron core frame and third iron core frame, first iron core frame and second iron core frame shape are the same, and first iron core frame and second iron core frame all are less than third iron core frame, first iron core frame, second iron core frame and third iron core frame are rolled up by the wide silicon steel sheet of different sheets respectively and are formed, first iron core frame and the adjacent setting of second iron core frame just all are wrapped up by third iron core frame, third iron core frame constitutes the iron core post respectively with the adjacent limit of first iron core frame and second iron core frame and the adjacent limit of second first iron core frame and second iron core frame, high-pressure coil and low-voltage coil suit respectively on three iron core post.

2. The folded core for a dry type transformer according to claim 1, wherein: the iron core body cross section is two rectangles to piecing together the structure.

3. The folded core for a dry type transformer according to claim 2, wherein: the butt joint ports of the silicon steel sheets are arranged in the middle of the bottoms of the first iron core frame/the second iron core frame/the third iron core frame.

4. The folded core for a dry type transformer according to claim 3, wherein: the cross section of the iron core body is provided with a bevel.

5. The folded core for a dry type transformer according to claim 4, wherein: and the clearance between the first iron core frame and the second iron core frame/the third iron core frame is less than 4 mm.

6. The folded core for a dry type transformer according to claim 5, wherein: and the clearance between the first iron core frame and the second iron core frame/the third iron core frame is less than 2 mm.

7. The folded core for a dry type transformer according to claim 6, wherein: a ladder is also arranged; the step length of each step is more than 5 mm.

8. The folded core for a dry type transformer according to claim 7, wherein: the novel steel plate is characterized by further comprising a step seam, the number of steps of the step seam is not less than 5, and the thickness between adjacent layers is not more than 0.015 mm.

9. The folded core for a dry type transformer according to claim 8, wherein: the length of the step seam from the corner is more than 10 mm.

10. The folded core for a dry type transformer according to claim 4, wherein: the angle of the break angle is 135 degrees.