CN116052982A

CN116052982A - High-frequency transformer with low-loss magnetic core structure

Info

Publication number: CN116052982A
Application number: CN202310076501.7A
Authority: CN
Inventors: 宋文乐; 王磊; 韩学; 郝翔宇
Original assignee: State Grid Corp of China SGCC; Cangzhou Power Supply Co of State Grid Hebei Electric Power Co Ltd
Current assignee: State Grid Corp of China SGCC; Cangzhou Power Supply Co of State Grid Hebei Electric Power Co Ltd
Priority date: 2023-02-03
Filing date: 2023-02-03
Publication date: 2023-05-02

Abstract

The invention provides a high-frequency transformer with a low-loss magnetic core structure, which comprises a transformer box, a side sealing cover and a plurality of transformer units, wherein the inside of the transformer box is divided into a plurality of installation cavities, and the inner wall of each installation cavity is lined with a radiating fin; the transformation unit comprises a magnetic core and a coil winding, wherein the magnetic core comprises an upper yoke, a lower yoke, a middle post and an outer side post, and the coil winding is wound on the periphery of the middle post; the intermediate column comprises a plurality of single magnetic blocks and insulating pads. The high-frequency transformer with the low-loss magnetic core structure provided by the invention adopts a mode of combining the middle column and the plurality of outer columns, and the plurality of magnetic blocks and the insulating pad are arranged at intervals to form the air gap between the two adjacent magnetic blocks, so that the thickness of a single air gap is conveniently reduced, the air gap diffraction effect is further reduced, the effect of reducing the coil winding loss is finally realized, the effect of reducing the overall temperature of the high-frequency transformer is realized, and the stable operation of the high-frequency transformer is ensured.

Description

High-frequency transformer with low-loss magnetic core structure

Technical Field

The invention belongs to the technical field of transformer equipment, and particularly relates to a high-frequency transformer with a low-loss magnetic core structure.

Background

The high-frequency transformer is a power transformer with the working frequency exceeding the intermediate frequency (10 kHz), and is mainly used as a high-frequency switching power transformer in a high-frequency switching power supply, and also used as a high-frequency inversion power transformer in a high-frequency inversion power supply and a high-frequency inversion welding machine. In the power electronic transformer, the high-frequency transformer realizes voltage conversion, power transmission and electrical isolation of the two-side converter devices, and becomes a hub for energy exchange of the two-side power electronic devices. As power electronics voltage, capacity and switching frequency increase, higher demands are also placed on the performance of high frequency transformer core materials to provide higher saturation flux densities and lower power losses for the core materials.

In order to achieve energy storage, prevent saturation of the magnetic core and achieve small fluctuation of inductance in a high-current working state, an air gap is usually required to be formed on a magnetic path of a conventional ferrite magnetic core to meet the performance requirement of a product.

However, the magnetic flux at the air gap is prone to diffuse leakage, the leakage magnetic flux cuts adjacent windings, high-frequency eddy current loss is generated in the windings, the additional eddy current loss greatly increases the power loss of the transformer, increases the operating temperature rise of the transformer, and reduces the efficiency of the transformer.

On the basis, as the switching frequency is increased, the additional high-frequency eddy current loss near the air gap is increased remarkably, and the complexity of the transformer production process is increased. In the operation process of the high-frequency transformer, the transformer is often overheated locally due to the excessively high core loss, so that the operation efficiency and stability of the transformer are affected, and the operation quality of related equipment is reduced. In addition, there is a higher demand for the performance of the high frequency transformer core material, which should have a higher saturation magnetic flux density and lower power loss.

Disclosure of Invention

The invention aims to provide a high-frequency transformer with a low-loss magnetic core structure, which can effectively improve the saturation magnetic flux density of the transformer, improve the heat dissipation efficiency of the transformer, reduce the power consumption of the transformer and facilitate the prolonging of the service life of the high-frequency transformer.

In order to achieve the above purpose, the invention adopts the following technical scheme: the high-frequency transformer with the low-loss magnetic core structure comprises a transformer box with side openings, a side sealing cover detachably connected to the transformer box to seal the side openings, and a plurality of transformer units respectively arranged in the transformer box, wherein the inside of the transformer box is divided into a plurality of installation cavities, and the inner wall of each installation cavity is lined with a radiating fin;

the transformation unit comprises a magnetic core and a coil winding, wherein the magnetic core comprises an upper yoke, a lower yoke arranged below the upper yoke, a middle column arranged between the upper yoke and the lower yoke and a plurality of outer side columns arranged on the peripheries of the upper yoke and the lower yoke, and the coil winding is wound on the periphery of the middle column;

the middle column comprises a plurality of single magnetic blocks arranged at intervals and an insulating pad arranged between two adjacent magnetic blocks to separate the two adjacent single magnetic blocks and form an air gap.

In one possible implementation, the coil winding includes a primary coil and a secondary coil wound around the outer periphery of the intermediate post, the primary coil and the secondary coil being spaced apart in the axial direction of the intermediate post;

the periphery cover of intermediate post is equipped with the first insulating disk that is used for winding up primary coil and is used for winding up secondary coil's second insulating disk, and first insulating disk and second insulating disk are equipped with the spacing chamber of indent setting in order to spacing secondary coil or primary coil axial position on the periphery wall of intermediate post in the axial of intermediate post interval setting.

In some embodiments, a plurality of heating panels connected with the bottom wall of the limiting cavity are arranged in the limiting cavity, the panel surface of the heating panels is perpendicular to the axial direction of the middle column, the heating panels are arranged at intervals in the axial direction of the first insulating disc or the second insulating disc, the outer edge of the heating panels is provided with a thickening part used for contacting with the primary coil or the secondary coil and exchanging heat, and the top surface and the bottom surface of the thickening part are gradually inclined towards the opposite side to form an arc surface.

In some embodiments, after the primary coil is wound on the first insulating disc, the primary coil is arranged to protrude outwards from the outer peripheral wall of the first insulating disc, and the primary coil positioned at the outermost ring is arranged to protrude outwards from the inner peripheral wall of the outer side column;

after the secondary coil is wound on the second insulating disc, the secondary coil outwards protrudes from the outer peripheral wall of the second insulating disc, and the secondary coil positioned at the outermost ring outwards protrudes from the inner peripheral wall of the outer side column.

In one possible implementation mode, the insulating pads and the magnetic blocks are connected in an adhesive mode through an adhesive layer, the thickness of each insulating pad is smaller than that of each magnetic block, four insulating pads are arranged between two adjacent magnetic blocks, and the four insulating pads are arranged on the surfaces of the magnetic blocks in a rectangular mode; the magnetic block is made of amorphous alloy material, nanocrystalline alloy material or soft magnetic ferrite material.

In one possible implementation, the upper yoke and the lower yoke are respectively circular plate-shaped members, the inner side walls of the outer side columns are attached to the outer peripheral walls of the upper yoke and the lower yoke, and the outer side walls are attached to the inner cavity walls of the mounting cavity;

the middle column is a circular component, a plurality of first arc-shaped cavities are formed in the transformer box, a plurality of second arc-shaped cavities are formed in the side sealing cover, and the first arc-shaped cavities and the second arc-shaped cavities are spliced to form a mounting cavity for accommodating the magnetic core and the coil winding.

In some embodiments, the inner cavity cross-sectional area of the first arcuate cavity is greater than the inner cavity cross-sectional area of the second arcuate cavity;

the opening side of the first arc-shaped cavity is also provided with an extension cavity which extends vertically towards one side of the side sealing cover, and the width of the inner cavity of the extension cavity is equal to the inner diameter of the cavity of the first arc-shaped cavity.

In some embodiments, an embedded cavity is arranged on the inner cavity wall of the first arc-shaped cavity in a concave manner, the radiating fins are arranged in the embedded cavity, and the inner walls of the radiating fins are flush with the inner wall of the first arc-shaped cavity so that the peripheral wall of the voltage transformation unit is in contact fit with the radiating fins.

In one possible implementation, the outer column comprises:

the magnetic arc plates are arranged at intervals along the axial direction of the upper yoke, are horizontally arranged in one-to-one correspondence with the magnetic blocks, and are provided with inner cambered surfaces attached to the peripheral wall of the upper yoke and outer cambered surfaces attached to the inner cavity wall of the mounting cavity;

the insulating blocks are arranged at intervals with the magnetic arc plates, are positioned between two adjacent magnetic arc plates and are horizontally arranged in one-to-one correspondence with the insulating pads.

In one possible implementation, the transformer tank and the side cover are respectively provided with a cooling interlayer, and the transformer tank and the side cover are respectively provided with cooling cavities which are positioned between adjacent mounting cavities and are communicated with the cooling interlayer.

Compared with the prior art, the high-frequency transformer with the low-loss magnetic core structure provided by the embodiment of the application adopts a mode that the middle post is combined with a plurality of outer posts, and the plurality of magnetic blocks and the insulating pad are arranged at intervals to form an air gap between two adjacent magnetic blocks, so that the thickness of a single air gap is conveniently reduced, the air gap diffraction effect is further reduced, the effect of reducing the loss of a coil winding is finally realized, the heat generated by the coil winding is finally reduced, the heat exchange effect of the coil winding and the cavity wall of an installation cavity is combined, the effect of reducing the overall temperature of the high-frequency transformer is realized, and the stable operation of the high-frequency transformer is ensured; meanwhile, the magnetic core structure is improved, so that the loss of the magnetic core is reduced in a wider frequency range, the performance of the high-frequency transformer is optimized, and the no-load characteristic and the magnetic core performance of the high-frequency transformer are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of a front view of a magnetic core, a first insulating sleeve, and a second insulating sleeve of a high-frequency transformer with a low-loss magnetic core structure according to an embodiment of the present invention;

FIG. 2 is a schematic view of a partial enlarged structure of I in FIG. 1 according to an embodiment of the present invention;

FIG. 3 is a schematic diagram illustrating a front view of the magnetic core of FIG. 1 according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a front view structure of a transformer unit according to an embodiment of the present invention;

FIG. 5 is a schematic top view of the transformer unit of FIG. 4 according to an embodiment of the present invention;

FIG. 6 is a schematic top cross-sectional view of the transformer unit of FIG. 4 in accordance with an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a high-frequency transformer with a low-loss magnetic core structure according to an embodiment of the present invention;

FIG. 8 is a schematic front view of the transformer box of FIG. 7 according to an embodiment of the present invention;

fig. 9 is a schematic top cross-sectional view of fig. 7 in accordance with an embodiment of the present invention.

Wherein, each reference sign in the figure:

1. a transformer box;

11. a side cover;

2. a transformation unit;

21. a heat sink;

3. a magnetic core;

31. an upper yoke; 32. a lower yoke; 33. a middle column; 34. an outer column; 35. a single magnetic block; 36. an insulating pad; 37. a magnetic arc plate; 38. an insulating block;

4. a coil winding;

41. a primary coil; 42. a secondary coil;

51. a first insulating disk; 52. a second insulating disk; 53. a spacing cavity;

6. a heat dissipation plate;

61. a thickening portion;

7. a mounting cavity;

71. a first arcuate cavity; 72. a second arcuate cavity; 73. an extension lumen;

8. cooling the interlayer;

81. and a cooling chamber.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved more clear, the invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or be indirectly on the other element. It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate describing the present invention and simplify the description, and do not indicate or imply that the devices or elements being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the present invention.

The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated.

Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, the meaning of "a number" is two or more, unless explicitly defined otherwise.

Referring to fig. 1 to 9 together, a high frequency transformer with a low loss magnetic core structure according to the present invention will now be described. The high-frequency transformer with the low-loss magnetic core structure comprises a transformer box 1 with a side opening, a side sealing cover 11 detachably connected to the transformer box 1 for sealing the side opening and a plurality of transformer units 2 respectively arranged in the transformer box 1, wherein the inside of the transformer box 1 is divided into a plurality of installation cavities 7, and the inner wall of each installation cavity 7 is lined with a radiating fin 21;

the transforming unit 2 includes a magnetic core 3 and a coil winding 4, the magnetic core 3 includes an upper yoke 31, a lower yoke 32 disposed below the upper yoke 31, a middle post 33 disposed between the upper yoke 31 and the lower yoke 32, and a plurality of outer posts 34 disposed at the outer circumferences of the upper yoke 31 and the lower yoke 32, and the coil winding 4 is wound around the outer circumference of the middle post 33;

the middle column 33 includes a plurality of single magnetic blocks 35 arranged at intervals, and an insulating pad 36 arranged between two adjacent magnetic blocks to separate the two adjacent single magnetic blocks 35 and form an air gap.

Compared with the prior art, the high-frequency transformer with the low-loss magnetic core structure provided by the embodiment adopts a mode that the middle post 33 and the plurality of outer side posts 34 are combined, and the plurality of magnetic blocks and the insulating pad 36 are arranged at intervals to form an air gap between two adjacent magnetic blocks, so that the thickness of a single air gap is conveniently reduced, the air gap diffraction effect is reduced, the effect of reducing the loss of the coil winding 4 is finally realized, the heat generated by the coil winding 4 is finally reduced, the effect of reducing the overall temperature of the high-frequency transformer is realized by combining the arrangement of the radiating fins 21 and the heat exchange effect of the coil winding 4 and the cavity wall of the installation cavity 7, and the stable operation of the high-frequency transformer is ensured; meanwhile, the structure of the magnetic core 3 is improved, so that the loss of the magnetic core 3 is reduced in a wider frequency range, the performance optimization of the high-frequency transformer is realized, and the no-load characteristic and the magnetic core performance of the high-frequency transformer are improved.

The high-frequency transformer is easy to generate electromagnetic interference and has higher temperature rise under the working state. The plurality of transformation units 2 are arranged in the same transformation box 1 to inhibit the adverse effect of parasitic parameters, the plurality of installation cavities 7 in the transformation box 1 are utilized for installation and layout, and the radiating fins 21 in the installation cavities 7 can radiate the single transformation unit 2, so that the radiating performance of the transformation unit 2 is improved, the structural layout is reasonable, the adverse effect of the parasitic parameters is greatly inhibited, the power density of the transformer is improved, and the no-load characteristic and the magnetic core performance of the high-frequency transformer are improved.

In one possible implementation, the above-described characteristic coil winding 4 adopts a structure as shown in fig. 4. Referring to fig. 4, the coil winding 4 includes a primary coil 41 and a secondary coil 42 wound around the outer periphery of the intermediate leg 33, the primary coil 41 and the secondary coil 42 being disposed at intervals in the axial direction of the intermediate leg 33;

the outer periphery of the intermediate post 33 is sleeved with a first insulating disc 51 for winding the primary coil 41 and a second insulating disc 52 for winding the secondary coil 42, the first insulating disc 51 and the second insulating disc 52 are arranged at intervals in the axial direction of the intermediate post 33, and limiting cavities 53 which are concavely arranged on the outer peripheral walls of the first insulating disc 51 and the second insulating disc 52 to limit the axial position of the secondary coil 42 or the primary coil 41 are arranged.

In the present embodiment, the coil winding 4 includes a primary coil 41 and a secondary coil 42. The primary coil 41 and the secondary coil 42 are respectively diffracted on the outer periphery of the intermediate post 33, and are respectively restrained by a first insulating plate 51 and a second insulating plate 52. The limiting cavity 53 on the first insulating disc 51 can limit the winding position of the primary coil 41, and the limiting cavity 53 on the second insulating disc 52 can limit the winding position of the secondary coil 42 on the periphery of the middle post 33, so that the two coils can be reasonably distributed in the axial direction of the middle post 33, and reasonable space application is realized.

Further, after the primary coil 41 and the secondary coil 42 are wound, the outer peripheral wall of the primary coil 41 protrudes outwards from the outer peripheral wall of the first insulating disc 51, and the outer peripheral wall of the secondary coil 42 protrudes outwards from the outer peripheral wall of the second insulating disc 52, so that the outer peripheral walls of the primary coil 41 and the secondary coil 42 can be directly contacted with the inner cavity wall of the mounting cavity 7, the heat exchange efficiency between the primary coil 41 and the secondary coil 42 and the cooling interlayer 8 of the transformer box 1 is improved, the surface temperature of the coil is reduced, the heat dissipation efficiency is improved, and the problem of overhigh temperature rise of the coil is avoided.

Specifically, the limiting cavity 53 has a rectangular cavity structure on the longitudinal section of the first insulating disc 51, so that the primary coil 41 can be effectively limited in the winding space position, and the primary coil 41 can be reasonably arranged conveniently, so that the occupied space of the primary coil 41 is reduced.

Similarly, the limiting cavity 53 has a rectangular cavity structure on the longitudinal section of the second insulating disc 52, so that the secondary coil 42 can be effectively limited in winding space position, and the primary coil 41 can be reasonably arranged, so that the occupied space of the secondary coil 42 is reduced.

In one possible implementation, the feature-limiting cavity 53 is configured as shown in fig. 1-2. Referring to fig. 1 to 2, a plurality of heat dissipation plates 6 connected with the bottom wall of the limiting cavity 53 are disposed in the limiting cavity 53, the plate surface of the heat dissipation plate 6 is perpendicular to the axial direction of the middle post 33, the heat dissipation plates 6 are disposed at intervals in the axial direction of the first insulating disc 51 or the second insulating disc 52, a thickening portion 61 for contacting with the primary coil 41 or the secondary coil 42 and exchanging heat is disposed at the outer edge of the heat dissipation plate 6, and the top surface and the bottom surface of the thickening portion 61 gradually incline towards the opposite side to form an arc surface.

In this embodiment, the heat dissipation plate 6 may directly cool the primary coil 41 and the secondary coil 42, and on the basis of cooling the peripheral wall of the wound primary coil 41 or secondary coil 42 by using the heat dissipation plate 21 in the mounting cavity 7, a plurality of heat dissipation plates 6 are further disposed in the axial direction of the middle part, and the heat dissipation plates 6 may cool the primary coil 41 and the secondary coil 42 in different axial positions, and may also play a role in supporting and limiting the primary coil 41 and the secondary coil 42.

On the basis, the thickening part 61 arranged on the outer edge of the heat radiation plate 6 is convenient for enlarging the basic area of the primary coil 41 and the secondary coil 42, improves the heat radiation uniformity, avoids the influence on the normal operation of the transformer caused by the excessively fast temperature rise in the coil, and is beneficial to prolonging the service life of the transformer.

In some embodiments, after the primary coil 41 is wound on the first insulating disc 51, the primary coil 41 is disposed outwardly protruding from the outer peripheral wall of the first insulating disc 51, and the primary coil 41 located at the outermost ring is disposed outwardly protruding from the inner peripheral wall of the outer column 34;

after the secondary coil 42 is wound around the second insulating disk 52, the secondary coil 42 is disposed so as to protrude outward from the outer peripheral wall of the second insulating disk 52, and the secondary coil 42 located at the outermost ring is disposed so as to protrude outward from the inner peripheral wall of the outer column 34.

On the basis of the above structure, since the primary coil 41 and the secondary coil 42 have a certain flexibility, the primary coil 41 and the secondary coil 42 are subjected to the restraining action of the outer leg 34 after being wound on the first insulating disk 51 or the second insulating disk 52, but there is also a tendency that part of the primary coil 41 and the secondary coil 42 have a convex tendency toward the outer periphery, forming an effect of restraining the convex inner peripheral wall of the outer leg 34, even reaching an effect of being flush with the outer peripheral wall of the outer leg 34, facilitating the primary coil 41 and the secondary coil 42 to be in effective contact with the inner cavity wall (i.e., the heat sink 21) of the installation cavity 7, and improving the heat dissipation efficiency.

In one possible implementation manner, the insulating pads 36 are connected with the magnetic blocks in an adhering manner through an adhesive layer, the thickness of each insulating pad 36 is smaller than that of each magnetic block, four insulating pads 36 are arranged between two adjacent magnetic blocks, and the four insulating pads 36 are arranged in a rectangular shape on the surfaces of the magnetic blocks; the magnetic block is made of amorphous alloy material, nanocrystalline alloy material or soft magnetic ferrite material.

In this embodiment, the insulating pad 36 and the magnetic block are bonded into a whole by using the adhesive layer, so that the bonding is firm and reliable, and the integrity of the intermediate column 33 is ensured. The thickness of the insulating pad 36 is smaller, so that the air gap formed between two adjacent magnetic blocks is effectively reduced, the air gap diffraction effect is reduced, the loss of the coil winding 4 is reduced, the heat generated by the coil winding 4 is further reduced, and the service life of the product is prolonged.

On this basis, a plurality of insulating pads 36 are provided between two adjacent magnetic blocks, and the two adjacent magnetic blocks are effectively separated by four insulating pads 36. By reducing the thickness of the insulating pad 36, the thickness of the air gap between the magnets is kept small, and the diffraction width is reduced.

The structure can also make the product design more compact, and reduce the volume of the transformation unit 2. In order to ensure the operability of the manufacturing process, the air gap can be made of insulating paper with a certain thickness or a backing plate made of insulating materials.

Further, the magnetic block is made of a soft magnetic ferrite amorphous alloy material, a nanocrystalline alloy material or a soft magnetic ferrite material. Soft magnetic ferrites can be generally classified into three main categories, power ferrites, high permeability ferrites and anti-electromagnetic interference ferrites. The main characteristic of the power ferrite is that the power loss is kept low under the high frequency magnetic induction intensity, and the power loss does not increase sharply with the temperature rise, and the power ferrite has the minimum value at 60-100 ℃, so that the magnetic core is in a virtuous circle.

The power ferrite is mainly used in various switching power supply transformers and power type inductive devices represented by flyback transformers of color televisions, has a very wide application range and is a soft magnetic ferrite material with the largest yield at present. The ferrite with high magnetic permeability is mainly characterized by high initial magnetic permeability and low loss factor in a weak field. The ferrite with high magnetic permeability is mainly used in a broadband inductor, a pulse transformer and an electronic ballast.

The ferrite is mainly characterized in that the ferrite material is utilized to absorb a large amount of electromagnetic interference signals by utilizing an electromagnetic loss mechanism of the ferrite material, so that the purpose of resisting electromagnetic interference is achieved, and the ferrite is mainly used for inductors, anti-electromagnetic interference filters, suppressors, chip inductors and the like.

In addition, since the soft magnetic ferrite has advantages such as high resistivity, good machinability, easy compression molding, good stability, low cost, etc., the effect is relatively good in the use of the high frequency transformer. As the switching power supply is advanced toward high frequency, small size and light weight, planar mounting, the requirements for soft magnetic ferrite materials are also increasing. Soft magnetic ferrites are continually evolving towards three aspects of higher frequencies, higher permeability and lower losses.

In one possible implementation, the above-described features of the upper yoke 31 and the lower yoke 32 adopt a structure as shown in fig. 5 and 6. Referring to fig. 5 and 6, the upper yoke 31 and the lower yoke 32 are circular plate-like members, respectively, and the inner side walls of the outer columns 34 are attached to the outer peripheral walls of the upper yoke 31 and the lower yoke 32, and the outer side walls are attached to the inner chamber walls of the installation chamber 7; the middle column 33 is a circular component, the transformer box 1 is provided with a plurality of first arc-shaped cavities 71, the side sealing cover 11 is provided with a plurality of second arc-shaped cavities 72, and the first arc-shaped cavities 71 and the second arc-shaped cavities 72 are spliced to form a mounting cavity 7 for accommodating the magnetic core 3 and the coil winding 4.

In the above-mentioned structure, set up upper yoke 31 and lower yoke 32 into circularly, have with installation cavity 7 bigger area of contact, be convenient for make the heat on the peripheral wall of coil winding 4 evenly distribute, avoid the heat accumulation at local point position, have good heat dissipation effect.

Further, the inner cavity sectional area of the first arc-shaped cavity 71 is larger than the inner cavity sectional area of the second arc-shaped cavity 72; the opening side of the first arc-shaped cavity 71 is further provided with an extension cavity 73 extending vertically to one side of the side cover 11, and the inner cavity width of the extension cavity 73 is equal to the inner cavity diameter of the first arc-shaped cavity 71.

In this embodiment, the arrangement of the extension cavity 73 provides sufficient operation space for the transformer unit 2 to install in the first arc cavity 71, and in addition, the buckling of the side cover 11 can make the peripheral wall of the coil winding 4 contact and cooperate with the inner cavity walls of the first arc cavity 71 and the second arc cavity 72 respectively, so that the heat dissipation area is increased, and the heat dissipation effect is improved.

In some embodiments, the above-mentioned characteristic transformer tank 1 and the side cover 11 may adopt a structure as shown in fig. 9. Referring to fig. 9, an embedded cavity is provided on the inner cavity wall of the first arc-shaped cavity 71, the heat sink 21 is installed in the embedded cavity, and the inner wall of the heat sink 21 is flush with the inner wall of the first arc-shaped cavity 71 so that the peripheral wall of the transformer unit 2 is in contact fit with the heat sink 21. The embedded cavity is used for installing the radiating fins 21, so that the radiating fins 21 are directly contacted with the coil winding 4, and the radiating effect of the coil winding is improved.

In one possible implementation, the above-mentioned feature transformer tank 1 and side cover 11 may adopt a structure as shown in fig. 5 and 6. Referring to fig. 5 and 6, the outer column 34 includes a plurality of magnetic arc plates 37 and a plurality of insulating blocks 38, the plurality of magnetic arc plates 37 are arranged at intervals along the axial direction of the upper yoke 31, the magnetic arc plates 37 are horizontally arranged in one-to-one correspondence with the magnetic blocks, and the magnetic arc plates 37 are provided with an inner arc surface attached to the peripheral wall of the upper yoke 31 and an outer arc surface attached to the inner cavity wall of the mounting cavity 7; the magnetic arc plates 37 are arranged at intervals, and the insulating blocks 38 are positioned between two adjacent magnetic arc plates 37 and are horizontally arranged in one-to-one correspondence with the insulating pads 36.

In the present embodiment, the outer leg 34 is composed of magnetic arc plates 37 attached to the outer peripheral walls of the upper yoke 31 and the lower yoke 32, and insulating blocks 38 arranged between adjacent two of the magnetic arc plates 37 at intervals. The magnetic arc plate 37 and the insulating block 38 are bonded and connected, so that the structural integrity of the whole outer side column 34 is ensured.

Specifically, the outer cambered surface of the magnetic arc plate 37 can be attached to the inner wall of the installation cavity 7, the inner cambered surface of the magnetic arc plate 37 can be attached to the inner peripheral wall of the coil winding 4, the space between two adjacent outer columns 34 can be used for the coil winding 4 to protrude and attach to the inner cavity wall of the installation cavity 7, the heat dissipation area of the coil winding 4 is effectively increased, and the heat dissipation effect is enhanced.

In some embodiments, the above-described feature transformer tank 1 and side covers 11 may adopt a structure as shown in fig. 9. Referring to fig. 9, the transformer tank 1 and the side cover 11 are respectively provided with a cooling interlayer 8, and the transformer tank 1 and the side cover 11 are respectively provided with a cooling cavity 81 which is positioned between the adjacent installation cavities 7 and is communicated with the cooling interlayer 8.

In this embodiment, the cooling fin 21 is used to radiate heat from the coil winding 4 in the installation cavity 7, and the cooling interlayer 8 is provided on each of the transformer box 1 and the side cover 11. The cooling interlayer 8 can be filled with heat exchange medium to realize heat exchange with the coil winding 4 in the installation cavity 7 and achieve the cooling effect of the coil winding 4.

Further, because the peripheral walls of the upper yoke 31, the lower yoke 32 and the outer side column 34 are all round, and the cross section of the installation cavity 7 is correspondingly round, a large space is formed at the periphery of the two adjacent installation cavities 7 on the transformer box 1 and the side sealing cover 11, and the space is provided with the cooling cavity 81 communicated with the cooling interlayer 8, so that the storage capacity of the heat exchange medium can be effectively increased, the heat exchange effect between the heat exchange medium and the coil windings 4 in the installation cavities 7 is improved, the transformer unit 2 has better cooling effect, the heat exchange efficiency is improved, and the energy consumption of the high-frequency transformer is reduced.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims

1. The high-frequency transformer with the low-loss magnetic core structure is characterized by comprising a transformer box with side openings, side sealing covers detachably connected to the transformer box to seal the side openings, and a plurality of transformer units respectively arranged in the transformer box, wherein the interior of the transformer box is divided into a plurality of installation cavities, and the inner wall of each installation cavity is lined with a radiating fin;

the transformer unit comprises a magnetic core and a coil winding, wherein the magnetic core comprises an upper yoke, a lower yoke arranged below the upper yoke, a middle column arranged between the upper yoke and the lower yoke and a plurality of outer columns arranged on the peripheries of the upper yoke and the lower yoke, and the coil winding is wound on the periphery of the middle column;

2. The high-frequency transformer with low-loss magnetic core structure according to claim 1, wherein said coil winding comprises a primary coil and a secondary coil wound around an outer periphery of said intermediate leg, said primary coil and said secondary coil being disposed at intervals in an axial direction of said intermediate leg;

the periphery cover of spliced pole is equipped with and is used for setting up primary coil's first insulating disk and is used for setting up secondary coil's second insulating disk, first insulating disk with the second insulating disk is in the axial of spliced pole is in the interval setting, be equipped with the indent setting on first insulating disk with the periphery wall of second insulating disk in order to spacing secondary coil or primary coil axial position's spacing chamber.

3. The high-frequency transformer with the low-loss magnetic core structure according to claim 2, wherein a plurality of radiating plates connected with the cavity bottom wall of the limiting cavity are arranged in the limiting cavity, the plate surfaces of the radiating plates are perpendicular to the axial direction of the middle column, the radiating plates are arranged at intervals in the axial direction of the first insulating disc or the second insulating disc, thickened parts for contacting with the primary coil or the secondary coil and exchanging heat are arranged at the outer edges of the radiating plates, and the top surfaces and the bottom surfaces of the thickened parts are gradually inclined towards the opposite side to form arc surfaces.

4. The high-frequency transformer with low-loss magnetic core structure according to claim 2, wherein after said primary coil is wound on said first insulating disk, said primary coil is arranged to protrude outwardly from an outer peripheral wall of said first insulating disk, and said primary coil located at an outermost ring is arranged to protrude outwardly from an inner peripheral wall of said outer column;

after the secondary coil is wound on the second insulating disc, the secondary coil outwards protrudes out of the outer peripheral wall of the second insulating disc, and the secondary coil positioned at the outermost ring outwards protrudes out of the inner peripheral wall of the outer column.

5. The high-frequency transformer with the low-loss magnetic core structure according to claim 1, wherein the insulating pads and the magnetic blocks are connected in an adhesive mode through an adhesive layer, the thickness of each insulating pad is smaller than that of each magnetic block, four insulating pads are arranged between two adjacent magnetic blocks, and the four insulating pads are arranged in a rectangular mode on the surfaces of the magnetic blocks; the magnetic block is an amorphous alloy material, a nanocrystalline alloy material or a soft magnetic ferrite material.

6. The high-frequency transformer with low-loss magnetic core structure according to any one of claims 1 to 5, wherein said upper yoke and said lower yoke are circular plate-like members, respectively, an inner side wall of said outer leg is fitted to an outer peripheral wall of said upper yoke and said lower yoke, and an outer side wall of said outer leg is fitted to an inner cavity wall of said installation cavity;

the middle column is a circular component, the transformer box is provided with a plurality of first arc-shaped cavities, the side sealing cover is provided with a plurality of second arc-shaped cavities, and the first arc-shaped cavities and the second arc-shaped cavities are spliced to form a mounting cavity for accommodating the magnetic core and the coil winding.

7. The high frequency transformer with low loss magnetic core structure according to claim 6, wherein a cross sectional area of an inner cavity of said first arc-shaped cavity is larger than a cross sectional area of an inner cavity of said second arc-shaped cavity;

the opening side of the first arc-shaped cavity is also provided with an extension cavity which extends vertically to one side of the side sealing cover, and the width of the inner cavity of the extension cavity is equal to the inner diameter of the cavity of the first arc-shaped cavity.

8. The high frequency transformer with low loss magnetic core structure according to claim 7, wherein an embedded cavity is provided on an inner cavity wall of the first arc cavity, the heat sink is installed in the embedded cavity, and an inner wall of the heat sink is flush with an inner wall of the first arc cavity so that a peripheral wall of the transforming unit is in contact fit with the heat sink.

9. The high frequency transformer with low loss magnetic core structure according to any of claims 1-5, wherein said outer leg comprises:

the insulation blocks are arranged at intervals with the magnetic arc plates, are positioned between two adjacent magnetic arc plates and are horizontally arranged in one-to-one correspondence with the insulation pads.

10. The high-frequency transformer with low-loss magnetic core structure according to any of claims 1-5, wherein a cooling interlayer is provided on each of said transformer tank and said side cover, and a cooling cavity is provided on each of said transformer tank and said side cover between adjacent ones of said mounting cavities and in communication with said cooling interlayer.