Low-voltage large-current flat transformer

Abstract

The invention discloses a low-voltage large-current flat transformer, and relates to the technical field of transformers, a transformer magnetic core is provided with a magnetic core middle column, a transformer winding comprises a first side winding and a second side winding, and the first side winding comprises a plurality of metal sheets; the metal sheet comprises a first end, a second end and a main body part, and the main body part is arranged in a waveform bending manner; wave crests formed by waveform bending extend along the extension path of the main body part and / or wave troughs formed by waveform bending extend along the extension path of the main body part; the wave crests and the wave troughs are respectively positioned on two surfaces of the metal sheet in the thickness direction; under the condition that the width size of the magnetic core of the transformer is limited, through the design, on one hand, the power-on cross sectional area of the main body part can be increased, and the allowed passing current is correspondingly increased, so that the flat transformer can be better used in low-voltage and high-current, and on the other hand, the heat dissipation area of the main body part can be greatly increased, and the heat dissipation efficiency is improved. When used in a low-voltage and large-current scene, the heat dissipation can be better carried out.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and particularly to a low-voltage large-current flat transformer. Background Art

[0002] Low-voltage large-current transformers play an important role in modern power conversion systems, especially in applications that require high efficiency, small size, and high reliability.

[0003] Currently, the structures of low-voltage large-current transformers are mostly like those of the Chinese utility model "Flat Coil and Ultra-thin LLC Transformer Suitable for Low-voltage Large-current" disclosed in the publication number CN218996503U, which uses flat copper sheets as one of the side windings. However, in low-voltage large-current applications, heat dissipation is a key issue. Common heat dissipation measures include using heat sinks, air cooling, liquid cooling, and forced convection cooling. How to improve the heat dissipation efficiency of the transformer structure itself is particularly crucial.

[0004] In addition, in some application scenarios, there are also relatively high requirements for the occupied space of the transformer. For example, on circuit boards or in small products, since multiple electronic components need to be designed simultaneously, the width of the transformer is required to be reduced as much as possible or not to be too large, which also makes it difficult to improve the heat dissipation of the transformer structure itself.

[0005] Furthermore, when used in low-voltage large-current applications, how to increase the magnitude of the current it can withstand is also particularly important. Summary of the Invention

[0006] The present invention aims to provide a technical solution that can solve the above problems to overcome the above deficiencies.

[0007] To achieve the above object, the present invention provides the following technical solution: A low-voltage large-current flat transformer includes a transformer core and a transformer winding. The transformer core has a core middle leg. The transformer winding includes a first side winding and a second side winding. The first side winding includes multiple metal sheets. The metal sheet includes a first end and a second end. The second end extends to surround the core middle leg, forming a main body portion that has the core middle leg sleeved therein between the first end and the second end. The main body portion has a middle opening corresponding to the sleeve of the core middle leg. Both the first end and the second end are provided with electrical connection portions. A base is provided on the transformer core, and electrical connection columns that cooperate with the electrical connection portions are provided on the base. In the width corresponding to the extension path of the main body portion, the main body portion is bent in a waveform. The wave peaks formed by the waveform bending extend along the extension path of the main body portion and / or the wave valleys formed by the waveform bending extend along the extension path of the main body portion. The wave peaks and wave valleys are respectively located on two surfaces in the thickness direction of the metal sheet.

[0008] As a further aspect of the present invention: on the total extension path from the first end to the main body and from the main body to the second end, the first end, the main body, and the second end are all waveform-bent; The wave crests on the first end are continuously arranged with the wave crests on the main body, and the wave crests on the main body are continuously arranged with the wave crests on the second end; The wave troughs on the first end are continuously arranged with the wave troughs on the main body, and the wave troughs on the main body are continuously arranged with the wave troughs on the second end.

[0009] As a further aspect of the present invention: the transformer core further has a side opening corresponding to the middle column of the core; the first end and the second end extend out of the transformer core toward the side opening of the transformer core and are exposed outside the transformer core.

[0010] As a further aspect of the present invention: the electrical connection part includes electrical connection holes opened on the corresponding first end and second end, and electrical connection columns are inserted into the corresponding electrical connection holes for electrical connection cooperation.

[0011] As a further aspect of the present invention: the electrical connection holes penetrate through the corresponding first end and second end along the thickness direction of the metal sheet.

[0012] As a further aspect of the present invention: on the width corresponding to the total extension path, both side edges of the electrical connection hole are located on the wave crest or both are located on the wave trough.

[0013] As a further aspect of the present invention: on the width corresponding to the total extension path, between the two edge wave crests or two edge wave troughs where the electrical connection hole is located, there is at least one intermediate wave crest and at least one intermediate wave trough.

[0014] As a further aspect of the present invention: on the width corresponding to the total extension path, there is at least one wave trough between the edge wave crest and the edge of the same side of the metal sheet, or there is at least one wave crest between the edge wave trough and the edge of the same side of the metal sheet.

[0015] As a further aspect of the present invention: after the electrical connection column is inserted into the electrical connection hole, the insertion position is tinned.

[0016] As a further aspect of the present invention: the waveform bending is arranged as a waveform bending with a radian, or the waveform bending is arranged as a waveform bending with an included angle.

[0017] Compared with the prior art, the beneficial effects of the present technical solution are as follows: when the width dimension of the transformer core is limited, through the above design, on the one hand, the cross-sectional area of the main body through which current passes can be increased, and the corresponding current that can pass through is increased, enabling the present flat transformer to be better used in low-voltage and high-current situations. On the other hand, the heat dissipation area of the main body can be significantly increased, and better heat dissipation can be achieved when used in low-voltage and high-current scenarios.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0020] Figure 1 is a schematic structural diagram of the present invention; Figure 2 is Figure 1 a structural cross-sectional view along the A-A direction in Figure 3 is Figure 2 a partially enlarged schematic view of the local structure at B in Figure 4 is a schematic structural diagram of the metal sheet of the present invention; Figure 5 is Figure 4 a structural cross-sectional view along the C-C direction in Figure 6 is a circuit schematic diagram of the present invention.

[0021] The corresponding reference numerals in the drawings are explained as follows: Center post of the core - 1, side openings - 2a, 2b, first side winding - 3, metal sheet - 31, insulating film - 32, first end - 311, second end - 312, main body - 313, middle opening - 314, peak - 315, middle peak - 315a, valley - 316, middle valley - 316a, edge valley - 316b, electrical connection hole - 317, second side winding - 4, coil - 41, base - 5, electrical connection post - 51, heat sink - 52, pin holding part - 53, metal pin - 54, peripheral part - 6. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0023] Please refer to Figures 1-6 , a low-voltage large-current flat transformer, including a transformer core and a transformer winding.

[0024] In this embodiment, the transformer core has a core middle column 1.

[0025] In some embodiments, the transformer core also has side openings 2a, 2b corresponding to the core middle column.

[0026] In some embodiments, the transformer core includes two E-shaped cores. The two E-shaped cores are made of ferrite, for example. After the two E-shaped cores are correspondingly assembled, an outer peripheral part 6 and a core middle column 1 are formed. The side openings 2a, 2b of the transformer core are correspondingly opened on the outer peripheral part 6. After the two E-shaped cores are correspondingly assembled, they can be adhesively fixed with glue.

[0027] In this embodiment, the transformer winding includes a first side winding 3 and a second side winding 4.

[0028] The first side winding 3 includes a plurality of metal sheets 31. The metal sheet 31 includes a first end 311 and a second end 312. The second end 312 extends to surround the core middle column 1, forming a main body part 313 that makes the first end 311 and the second end 312 have a sleeve on the core middle column 1. The main body part 313 has a middle opening 314 corresponding to the sleeve on the core middle column 1.

[0029] The first end 311 is connected to the second end 312 through the main body part 313. When energized, the current flows from the first end 311 through the main body part 313 and then from the main body part 313 to the second end 312, or the current flows from the second end 312 through the main body part 313 and then from the main body part 313 to the first end 311, forming a flow around the core middle column 1.

[0030] After a plurality of metal sheets 31 are all sleeved on the core middle column 1 through the middle openings on their main body parts, it can be understood that the plurality of metal sheets are arranged in sequence along the thickness direction of the metal sheet 31, or it can be understood that the plurality of metal sheets are arranged in sequence along the length direction of the core middle column 1.

[0031] Both the first end 311 and the second end 312 are provided with electrical connection parts. A base 5 is provided on the transformer core, and an electrical connection column 51 cooperating with the electrical connection parts is provided on the base 5.

[0032] In this embodiment, on the width corresponding to the extension path of the main body portion 313, the main body portion 313 is arranged in a waveform bending manner, and the wave crests 315 formed by the waveform bending extend along the extension path of the main body portion 313 and / or the wave troughs 316 formed by the waveform bending extend along the extension path of the main body portion 313.

[0033] For details, please refer to Figure 3 , and the wave crests 315 and the wave troughs 316 are respectively located on two surfaces in the thickness direction of the metal sheet 31.

[0034] In the case where the width dimension of the transformer core is limited, through the above design, on the one hand, the current-carrying cross-sectional area of the main body portion 313 can be increased, and the corresponding current that can pass through is increased, so that this flat transformer can be better used in low-voltage and high-current applications. On the other hand, the heat dissipation area of the main body portion 313 can be greatly increased, and when used in a low-voltage and high-current scenario, heat dissipation can be better performed.

[0035] In this embodiment, on the total extension path from the first end 311 to the main body portion 313 and from the main body portion 313 to the second end 312, the first end 311, the main body portion 313, and the second end 312 are all arranged in a waveform bending manner.

[0036] In some embodiments, at least some of the wave crests on the main body portion 313 are continuously arranged with the wave crests of the first end 311.

[0037] In some embodiments, at least some of the wave crests on the main body portion 313 are continuously arranged with the wave crests of the second end 312.

[0038] In some embodiments, at least some of the wave troughs on the main body portion 313 are continuously arranged with the wave troughs of the first end 311.

[0039] In some embodiments, at least some of the wave troughs on the main body portion 313 are continuously arranged with the wave troughs of the second end 312.

[0040] In this embodiment, the wave crests on the first end 311 are continuously arranged with the wave crests on the main body portion 313, and the wave crests on the main body portion 313 are continuously arranged with the wave crests on the second end 312; the wave troughs on the first end 311 are continuously arranged with the wave troughs on the main body portion 313, and the wave troughs on the main body portion 313 are continuously arranged with the wave troughs on the second end 312.

[0041] When energized, the increased current-carrying cross-sectional area of the first end 311 corresponds to the increased current-carrying cross-sectional area of the main body portion 313, and the increased current-carrying cross-sectional area of the main body portion 313 corresponds to the increased current-carrying cross-sectional area of the second end 312, which can better adapt to low-voltage and high-current operations.

[0042] Preferably, the first end 311 and the second end 312 extend out of the transformer core toward the side opening 2a of the transformer core.

[0043] After the first end 311 and the second end 312 extend out from the side opening 2a of the transformer core, they are exposed outside the transformer core. Through the increased heat dissipation area of the first end 311 and the second end 312, heat can be better dissipated outside the transformer core, achieving a double improvement in the heat dissipation efficiency inside and outside the transformer core.

[0044] In some embodiments, the waveform is bent into a waveform with a curvature. For example Figure 3 、 5 As shown, it is bent in a curved shape at the wave crest 315 and / or the wave trough 316.

[0045] In some embodiments, the waveform is bent into a waveform with an included angle, for example, it is bent at an included angle at the wave crest and / or the wave trough. In some embodiments, the electrical connection part includes electrical connection holes 317 opened on the corresponding first end 311 and second end 312. The electrical connection column 51 can be inserted into the corresponding electrical connection hole 317 to make contact electrical connection with the first end 311 or the second end 312.

[0046] When both the first end 311 and the second end 312 are bent in the above-mentioned waveform, in addition to increasing the heat dissipation area and the cross-sectional area for current conduction of the first end 311 and the second end 312, when the width of the electrical connection column 51 remains unchanged, it can also increase the contact area between the electrical connection column 51 and the corresponding first end 311 or second end 312, so that after the electrical connection column 51 is inserted into the corresponding electrical connection hole 317, it can be supported by a larger area, and the electrical connection column 51 and the corresponding first end 311 or second end 312 have a larger electrical contact area, enabling a larger current to flow between the metal sheet and the electrical connection column.

[0047] In some embodiments, after the electrical connection column 51 is inserted into the electrical connection hole 317, the electrical connection column and the metal sheet at the insertion position can be tinned to ensure the insertion stability and the stability and comprehensiveness of the electrical connection; and the above-mentioned waveform bending setting enables better tinning during tinning.

[0048] In some embodiments, the electrical connection hole 317 penetrates the corresponding first end 311 and second end 312 along the thickness direction of the metal sheet 31.

[0049] Such as Figure 1 、 4, as shown in FIGS. 6, in some embodiments, for example, three electrical connection posts 51 are provided on the base 5, and the first end and the second end of each metal sheet are respectively sleeved on one of the electrical connection posts through corresponding electrical connection holes. Such as Figure 2 , 6 shown, for example, there are 6 metal sheets. The circuit connection structure formed by the three electrical connection posts for the 6 metal sheets can refer to the schematic diagram of Figure 6 . N1, N2, N4, N5, N7, N8 correspond to 6 windings formed by the 6 metal sheets.

[0050] In some embodiments, the second side winding 4 includes a plurality of Litz three-layer insulated wire rods, and the Litz three-layer insulated wire rods are wound around the middle column of the magnetic core to form a coil 41.

[0051] Both ends of the coil 41 extend out from the other opening 2b of the transformer magnetic core, and two metal pins 54 electrically connected to both ends of the coil 41 are provided on the base 5.

[0052] Such as Figure 1 , 2 shown, in some embodiments, in the length direction of the middle column 1 of the magnetic core, the laminated structure of the transformer winding is the first side winding (formed by the first part of the metal sheets, such as Figure 6 N1, N2)-the second side winding (formed by the first part of the coils, such as Figure 6 N3)-the first side winding (formed by the second part of the metal sheets, such as Figure 6 N4, N5)-the second side winding (formed by the second part of the coils, such as Figure 6 N6)-the first side winding (formed by the third part of the metal sheets, such as Figure 6 N7, N8).

[0053] For example, if the first side winding is used as the primary winding and the second side winding is used as the secondary winding, then its laminated structure corresponds to primary-secondary-primary-secondary-primary.

[0054] In some embodiments, the metal sheet 31 is made of a copper sheet. Insulating films 32 are pasted on both surfaces of the metal sheet 31, for example, polyimide insulating films are pasted, so as to better insulate the metal sheet 31 from adjacent structures, for example, to insulate the metal sheet from adjacent metal sheets, for example, to insulate the metal sheet from adjacent second side windings.

[0055] In some embodiments, the base 5 is an epoxy base, and the base 5 is arranged in a plate shape.

[0056] In some embodiments, the base 5 has mounting holes corresponding to the middle column 1 of the magnetic core. The base 5 is sleeved on the middle column 1 of the magnetic core through the mounting holes and is close to one end of the middle column 1 of the magnetic core. The middle column 1 of the magnetic core can simultaneously constitute an anti-disengagement setting for the base 5.

[0057] The base 5 has two side pin holding parts 53 that extend out corresponding to the openings on both sides of the transformer core. The above-mentioned electrical connection posts 51 and metal pins 54 are respectively connected to the pin holding parts on the corresponding side. For example, the electrical connection post 51 is connected to the pin holding part on one side, and the metal pin 54 is connected to the pin holding part on the other side.

[0058] Preferably, the base 5 can be sleeved on the middle column 1 of the core through the pin holding part 53 and the mounting holes, so as to be rotationally restricted on the middle column 1 of the core. For example, the rotation of the base 5 on the middle column 1 of the core is restricted.

[0059] Preferably, the base 5 is embedded with a heat sink 52. One side of the heat sink 52 corresponds to the transformer winding, and the other side of the heat sink 52 corresponds to the peripheral part 6 close to the middle column of the core, so as to better transfer the heat of the transformer winding to the peripheral part 6 for heat dissipation.

[0060] In some embodiments, on the width corresponding to the total extension path, both side edges of the electrical connection hole 317 are located on the wave peaks or both are located on the wave valleys.

[0061] As Figure 5 shown, the wave valley 316 is mainly located between two adjacent wave peaks 315, and the wave peak 315 is mainly located between two adjacent wave valleys 316. Through the concave part formed between two adjacent wave peaks 315 or the convex part located between two adjacent wave valleys 316, better positioning can be achieved when punching the copper sheet.

[0062] In some embodiments, on the width corresponding to the total extension path, between the two edge wave peaks where the electrical connection hole 317 is located or between two edge wave valleys 316b, there is at least one intermediate wave peak 315a and at least one intermediate wave valley 316a.

[0063] Specifically, please refer to Figure 5 , between the two edge wave valleys 316b where the electrical connection hole 317 is located, there is at least one intermediate wave peak 315a and at least one intermediate wave valley 316a, and high-point contact and low-point contact can be formed simultaneously.

[0064] Actually, when both side edges of the electrical connection hole are located on the wave peaks, and there is at least one intermediate wave peak between the two edge wave peaks where the electrical connection hole is located, there are at least 2 intermediate wave valleys, and the intermediate wave peaks are correspondingly located between the 2 intermediate wave valleys. From one edge wave peak of the electrical connection hole to the other edge wave peak, at least one continuous structural sequence of wave peak - wave valley - wave peak - wave valley - wave peak is formed.

[0065] Similarly, when both side edges of the electrical connection hole are located on the wave troughs, and there is at least one intermediate wave trough between the two edge wave troughs where the electrical connection hole is located, that is, there are at least 2 intermediate wave peaks, and the intermediate wave troughs are correspondingly located between the 2 intermediate wave peaks, a continuous structural sequence of at least one wave trough - wave peak - wave trough - wave peak - wave trough is correspondingly formed from one edge wave trough of the electrical connection hole to the other edge wave trough. In some embodiments, on the width corresponding to the total extension path, there is at least one wave trough between the edge wave peak and the edge of the same side of the metal sheet, or there is at least one wave peak between the edge wave trough and the edge of the same side of the metal sheet.

[0066] Specifically, please refer to Figure 5 , there is at least one wave peak between the edge wave trough 316b and the edge of the same side of the metal sheet.

[0067] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non - restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

Claims

1. A low-voltage high-current flat transformer, comprising a transformer core and a transformer winding. The transformer core has a central core column, and the transformer winding includes a first side winding and a second side winding. It is characterized in that the first side winding includes a plurality of metal sheets; the metal sheet includes a first end and a second end, and the second end extends to surround the central core column, forming a main body portion sleeved on the central core column between the first end and the second end. The main body portion has a central opening corresponding to the sleeve of the central core column; electric connection portions are provided on both the first end and the second end, a base is provided on the transformer core, and electric connection columns are provided on the base and are in cooperation with the electric connection portions; in the width corresponding to the extension path of the main body portion, the main body portion is bent in a waveform; the wave peaks formed by the waveform bending extend along the extension path of the main body portion and / or the wave valleys formed by the waveform bending extend along the extension path of the main body portion; the wave peaks and wave valleys are respectively located on two surfaces in the thickness direction of the metal sheet.

2. The low-voltage high-current flat transformer according to claim 1, wherein On the total extension path from the first end to the main body portion and from the main body portion to the second end, the first end, the main body portion, and the second end are all bent in a waveform; the wave peaks on the first end are continuously arranged with the wave peaks on the main body portion, and the wave peaks on the main body portion are continuously arranged with the wave peaks on the second end; the wave valleys on the first end are continuously arranged with the wave valleys on the main body portion, and the wave valleys on the main body portion are continuously arranged with the wave valleys on the second end.

3. The low-voltage large-current flat transformer according to claim 2, characterized in that, The transformer core also has side openings corresponding to the central core column; the first end and the second end extend out of the transformer core toward one side opening of the transformer core and are exposed outside the transformer core.

4. The low-voltage high-current flat transformer according to claim 2 or 3, characterized in that, The electric connection portion includes electric connection holes opened on the corresponding first end and second end, and the electric connection columns are inserted into the corresponding electric connection holes for electric connection cooperation.

5. The low-voltage large-current flat transformer according to claim 4, wherein The electric connection holes penetrate through the corresponding first end and second end along the thickness direction of the metal sheet.

6. The low-voltage high-current flat transformer according to claim 5, wherein, On the width corresponding to the total extension path, both side edges of the electric connection hole are located on the wave peak or both are located on the wave valley.

7. The low-voltage high-current flat transformer according to claim 6, wherein, On the width corresponding to the total extension path, between two edge wave peaks or two edge wave valleys where the electric connection hole is located, there is at least one intermediate wave peak and at least one intermediate wave valley.

8. The low-voltage high-current flat transformer according to claim 7, wherein On the width corresponding to the total extension path, there is at least one wave valley between the edge wave peak and the edge of the same side of the metal sheet, or there is at least one wave peak between the edge wave valley and the edge of the same side of the metal sheet.

9. The low-voltage high-current flat transformer according to any one of claims 5-8, characterized in that, After the electric connection column is inserted into the electric connection hole, the insertion position is tinned.

10. The low-voltage high-current flat transformer according to claim 1 or 2 or 3 or 5 or 6 or 7 or 8, characterized in that the waveform bending is set as a waveform bending with a radian, or the waveform bending is set as a waveform bending with an included angle.

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