Magnetic integrated transformer

Abstract

The utility model provides a magnetic integrated transformer, which comprises a magnetic core and a winding, the magnetic core is provided with a magnetic core middle column, the winding is arranged around the magnetic core middle column, the winding comprises a primary winding and a secondary winding which are laminated, and a ferrite film is arranged between the primary winding and the secondary winding. According to the magnetic integrated transformer, the loss of the secondary side duty ratio can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of transformers, and in particular to a magnetically integrated transformer. Background Art

[0002] ZVS (Zero Voltage Switching, full-bridge zero voltage switching) DC converters are widely used in medium and high power conversion applications. Its biggest feature is to use the resonance between the transformer leakage inductance and the switch parasitic capacitance to achieve zero voltage switching of the power switch. In the application process, the lagging bridge arm can meet the ZVS condition through a relatively large resonant inductance, but the increase in resonant inductance will simultaneously lead to an increase in the secondary side duty cycle loss, reducing the efficiency of the converter.

[0003] Therefore, it is necessary to provide an improved magnetic integrated transformer to solve the above problems. Utility Model Content

[0004] The present application provides a magnetically integrated transformer that reduces secondary side duty cycle loss.

[0005] The present application discloses a magnetic integrated transformer, comprising a magnetic core and a winding, wherein the magnetic core is provided with a magnetic core center column, the winding is arranged around the magnetic core center column, the winding comprises a primary winding and a secondary winding which are stacked, and a ferrite film is arranged between the primary winding and the secondary winding.

[0006] Furthermore, the ferrite film includes a substrate, a magnetic layer and an adhesive layer which are stacked in sequence, and the adhesive layer is attached to the primary winding or the secondary winding; the area of ​​the ferrite film is adjustable.

[0007] Furthermore, a spacer is provided between the primary winding and the secondary winding, the spacer is made of insulating material, and the thickness of the spacer is adjustable.

[0008] Furthermore, the secondary winding includes a first secondary winding, a second secondary winding, a third secondary winding and a fourth secondary winding arranged in sequence from top to bottom, and the primary winding includes a first primary winding located between the first secondary winding and the second secondary winding and a second primary winding located between the third secondary winding and the fourth secondary winding.

[0009] Furthermore, the ferrite film is disposed on both sides of the first primary winding and the second primary winding; and the spacer is disposed between the first primary winding and the second secondary winding and between the third secondary winding and the second primary winding.

[0010] Furthermore, the spacer includes at least one of a silicone member, an epoxy board, a DuPont paper, and a ceramic sheet.

[0011] Furthermore, the number of the primary windings and the number of the secondary windings are both several, each of the secondary windings includes two groups of secondary windings, and each of the primary windings includes a group of primary windings; each group of the secondary windings includes two layers of secondary windings connected in parallel, and each group of the primary windings includes two layers of primary windings connected in parallel.

[0012] Furthermore, the magnetically integrated transformer also includes pins connected to the secondary windings, the pins including a first pin, a second pin and a third pin arranged perpendicular to the windings, one group of secondary windings in each of the secondary windings is respectively connected to the first pin and the second pin, and the other group of secondary windings is respectively connected to the second pin and the third pin.

[0013] Furthermore, the magnetic core includes a first magnetic core and a second magnetic core that are relatively covered, and the magnetic core center column correspondingly includes a first magnetic core center column and a second magnetic core center column, and the first magnetic core center column and the second magnetic core center column are in contact with each other.

[0014] Furthermore, the primary winding is a coil structure, and the secondary winding is a copper bar structure; the magnetic integrated transformer also includes a bottom plate, and one end of the magnetic core is fixed on the bottom plate.

[0015] The magnetic integrated transformer of the present application increases the leakage inductance of the magnetic integrated transformer by setting a ferrite film between the primary winding and the secondary winding, and can maintain a large resonant inductance when lightly loaded to meet the zero voltage opening of the lagging bridge arm during the switching process, reduce switching losses, and improve conversion efficiency. As the load increases, the resonant inductance decays, avoiding the problem of loss of the secondary side duty cycle when the load increases, so that the magnetic integrated transformer can maintain efficient and stable operation.

[0016] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the specification and, together with the description, serve to explain the principles of the specification.

[0018] Figure 1 It is a three-dimensional diagram of an embodiment of the magnetic integrated transformer of the present application.

[0019] Figure 2 yes Figure 1 A three-dimensional image of the magnetically integrated transformer from another perspective.

[0020] Figure 3 yes Figure 1Exploded view of the magnetically integrated transformer in Figure 1.

[0021] Figure 4 is along Figure 1 Sectional view of AA.

[0022] Figure 5 yes Figure 1 A three-dimensional diagram of a set of primary windings of a China Magnetics integrated transformer.

[0023] Figure 6 yes Figure 1 A three-dimensional diagram of a set of secondary windings of a China Magnetics integrated transformer.

[0024] Figure 7 It is a schematic diagram of the structure of the ferrite film of the magnetic integrated transformer of the present application.

[0025] Description of Figure Numbers:

[0026] 10. Magnetic core; 101. Magnetic core center column; 11. First magnetic core; 111. First magnetic core center column; 12. Second magnetic core; 121. Second magnetic core center column; 20. Winding; 201. Primary winding layer; 202. Secondary winding layer; 21. Primary winding; 21a. Primary winding unit; 211. First primary winding; 212. Second primary winding; 22. Secondary winding; 22a. First secondary winding unit; 22b. Second secondary winding unit; 221. First secondary winding; 222. Second secondary winding; 223. Third secondary winding; 224. Fourth secondary winding; 30. Ferrite film; 31. Substrate; 32. Magnetic layer; 33. Adhesive layer; 40. Spacer; 50. Pin; 51. First pin; 52. Second pin; 53. Third pin; 60. Bottom plate. DETAILED DESCRIPTION

[0027] Here, the technical solutions in the embodiments (or "implementation methods") of the present application will be described clearly and completely in conjunction with the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0028] If there are terms involving directional indications or positional relationships in the embodiments of the present application (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings); if the specific posture changes, the directional indication or positional relationship will also change accordingly. In addition, the terms "first" and "second" in the embodiments of the present application are only used for the purpose of convenience of description and cannot be understood as indicating or implying relative importance.

[0029] Next, the embodiments of the present application are described in detail. Figure 1 The direction of the arrow in the middle is up and down.

[0030] The present application provides a magnetic integrated transformer, which is used in the fields of switching power supplies, power electronics, signal transmission, industrial control, etc. to perform voltage conversion, voltage adjustment, etc. to ensure the performance and reliability of the circuit.

[0031] like Figure 1 and Figure 2 As shown, the magnetic integrated transformer of the present application includes a magnetic core 10 and a winding 20. The magnetic core 10 is provided with a magnetic core center column 101, and the winding 20 is arranged around the magnetic core center column 101.

[0032] Please also refer to Figure 3 In this embodiment, the magnetic core 10 includes a first magnetic core 11 and a second magnetic core 12 that are relatively covered. The magnetic core center column 101 includes a first magnetic core center column 111 disposed on the first magnetic core 11 and a second magnetic core center column 121 disposed on the second magnetic core 12. The winding 20 is disposed between the first magnetic core 11 and the second magnetic core 12, and surrounds the first magnetic core center column 111 and the second magnetic core center column 121.

[0033] The first magnetic core 11 and the second magnetic core 12 are attached to each other, and the first magnetic core middle column 111 and the second magnetic core middle column 121 are attached to each other, and the overall structure is relatively compact and small. In this embodiment, the first magnetic core 11 and the second magnetic core 12 are fixed by gluing. In some cases, they can also be fixed by other methods such as welding, snap connection, plug-in, etc.

[0034] Specifically, the first magnetic core 11 and the second magnetic core 12 of the present embodiment are both PQ65 type magnetic cores, which perform well under high frequency conditions, can effectively improve the efficiency of the transformer, can better transfer energy in high frequency circuits such as switching power supplies, and reduce core losses. And the thermal stability is good, which can effectively dissipate heat, maintain a stable operating temperature, and avoid performance degradation or damage caused by overheating. In addition, the PQ65 type magnetic core has a good magnetic shielding effect, which can reduce electromagnetic interference to adjacent connected switching electrical components to avoid overvoltage breakdown of electrical components, thereby enhancing the anti-saturation ability of the magnetic integrated transformer and the stability of the resonance of the entire circuit, making the power supply more reliable, thereby further improving work efficiency.

[0035] In some cases, the type of the magnetic core 10 can also be flexibly selected according to actual needs, and this application does not impose any restrictions on this.

[0036] like Figure 3 and Figure 4As shown, the winding 20 includes a primary winding 21 and a secondary winding 22 stacked in the vertical direction. In this embodiment, the number of the primary winding 21 and the secondary winding 22 are both multiple, which can distribute the load current more evenly, which helps to improve the stability and reliability of the transformer on the one hand, and reduces the overload phenomenon of a single winding 20 on the other hand, thereby extending the service life of the transformer.

[0037] Specifically, the number of the secondary windings 22 is four, and the number of the primary windings is two. The secondary winding 22 includes a first secondary winding 221, a second secondary winding 222, a third secondary winding 223, and a fourth secondary winding 224 arranged sequentially from top to bottom, and the primary winding 21 includes a first primary winding 211 and a second primary winding 212 arranged sequentially from top to bottom. The first primary winding 211 is located between the first secondary winding 221 and the second secondary winding 222, and the second primary winding 212 is located between the third secondary winding 223 and the fourth secondary winding 224.

[0038] That is, from top to bottom, the winding 20 is sequentially arranged as the first secondary winding 221, the first primary winding 211, the second secondary winding 222, the third secondary winding 223, the second primary winding 212, and the fourth secondary winding 224. The stacked structure of the winding 20 in this embodiment is "secondary-primary-secondary-secondary-primary-secondary". In some cases, the stacked structure of the winding 20 in the magnetic integrated transformer of the present application can be flexibly arranged, such as being arranged as "primary-secondary-primary", "secondary-primary-secondary", "secondary-primary", etc.

[0039] Please also refer to Figure 5 The primary winding 21 in this embodiment is a coil structure, which can effectively reduce the skin effect and proximity effect, reduce high-frequency loss, and optimize electromagnetic compatibility. Each primary winding 21 includes a group of primary winding units 21a. Each group of primary winding units 21a includes two layers of primary winding layers 201 connected in parallel, and the two primary winding layers 201 are stacked.

[0040] Please also refer to Figure 6 The secondary winding 22 in this embodiment is a copper bar structure with low current transmission loss, good conductivity, strong heat dissipation ability, and large current carrying capacity. Each secondary winding 22 includes a first secondary winding unit 22a and a second secondary winding unit 22b that are stacked. The first secondary winding unit 22a and the second secondary winding unit 22b each include two layers of secondary winding layers 202 connected in parallel, and the two layers of secondary winding layers 202 are stacked. That is, each secondary winding 22 includes four layers of secondary winding layers 202.

[0041] It is understandable that the structural type of the primary winding 21 and the secondary winding 22 can also be set to a flat copper coil structure, a PCB winding structure, etc. The number of groups of each primary winding 21 and secondary winding 22, the number of layers of the first secondary winding unit 22a, the second secondary winding unit 22b and the primary winding unit 21a can also be flexibly designed. This application does not impose any restrictions on this.

[0042] like Figure 3 and Figure 4 As shown, a ferrite film 30 is disposed between the primary winding 21 and the secondary winding 22 to increase the leakage inductance of the magnetic integrated transformer.

[0043] The leakage inductance of the transformer is positively correlated with the number, magnetic permeability and area of ​​the ferrite film 30. The number, magnetic permeability and area of ​​the ferrite film 30 of the present application can be adjusted. When designing a magnetic integrated transformer, the leakage inductance of the transformer can be adjusted by adjusting the number, magnetic permeability and area of ​​the ferrite film 30 so that the transformer meets the set requirements.

[0044] Specifically, in this embodiment, ferrite films 30 are provided on both sides of the first primary winding 211 and the second primary winding 212. There are four ferrite films 30, which are respectively provided between the first secondary winding 221 and the first primary winding 211, between the first primary winding 211 and the second secondary winding 222, between the third secondary winding 223 and the second primary winding 212, and between the second primary winding 212 and the fourth secondary winding 224. The ferrite films 30 are all annular and cover the windings 20 in the up and down directions.

[0045] Please also refer to Figure 7 The ferrite film 30 of this embodiment includes a substrate 31, a magnetic layer 32 and an adhesive layer 33 which are stacked in sequence. The magnetic layer 32 is mainly composed of ferrite powder, is the core part of the ferrite film 30, and is responsible for providing magnetic function. The substrate 31 is made of rubber and covers the magnetic layer 32, providing flexibility and support. The adhesive layer 33 is used to attach to the primary winding 21 or the secondary winding 22. In this embodiment, since the copper bar structure is easy to bond, the adhesive layer 33 of the ferrite film 30 is attached to the secondary winding 22. In some cases, the ferrite film 30 can also be attached to the primary winding 21, or some of them are attached to the secondary winding 22 and the others are attached to the primary winding 21.

[0046] The thickness of the ferrite film 30 is 0.05mm-3mm, which is easy to assemble and does not occupy the internal space of the transformer in the height direction. During the assembly process of the magnetic integrated transformer, the ferrite film 30 can be directly attached to the primary winding 21 or the secondary winding 22 to improve the assembly efficiency and make the overall structure more solid and tight. In some cases, the ferrite film 30 may not be attached to the primary winding 21 or the secondary winding 22, but only contact the primary winding 21 or the secondary winding 22 to facilitate replacement and maintenance.

[0047] By providing the ferrite film 30, the leakage inductance of the magnetic integrated transformer is increased, and a large resonant inductance can be maintained when the load is light to meet the zero voltage opening of the lagging bridge arm during the switching process, reduce switching losses, and improve conversion efficiency. As the load increases, the resonant inductance decays, avoiding the problem of loss of the secondary side duty cycle when the load increases, so that the magnetic integrated transformer can maintain efficient and stable operation.

[0048] A spacer 40 is also provided between the primary winding 21 and the secondary winding 22. The spacer 40 is made of insulating material and has a certain thickness, which can open the gap between the primary winding 21 and the secondary winding 22, reduce the coupling between the primary winding 21 and the secondary winding 22 to a certain extent, and increase the leakage inductance.

[0049] In this embodiment, there are two spacers 40, which are respectively arranged between the first primary winding 211 and the second secondary winding 222 and between the third secondary winding 223 and the second primary winding 212. It is worth noting that a ferrite film 30 is also arranged between the first primary winding 211 and the second secondary winding 222 and between the third secondary winding 223 and the second primary winding 212. In this embodiment, the spacer 40 is located on the side close to the primary winding 21, and the ferrite film 30 is located on the side close to the secondary winding 22. The relative position of the ferrite film 30 and the spacer 40 can also be adjusted.

[0050] In this embodiment, the spacer 40 is a silicone member and has good thermal conductivity. In some cases, the spacer 40 can also be set as an epoxy board, DuPont paper, ceramic sheet, etc. The thickness of the spacer 40 can be adjusted to meet the leakage inductance requirements of the magnetic integrated transformer and the space limitation during assembly.

[0051] like Figure 1 and Figure 3As shown, the magnetic integrated transformer also includes a pin 50 connected to the secondary winding 22, which is used to lead out the secondary winding 22 and realize the connection between the secondary winding 22 and the circuit. The pin 50 includes a first pin 51, a second pin 52 and a third pin 53 arranged perpendicular to the winding 20. The first secondary winding unit 22a in each secondary winding 22 is connected to the first pin 51 and the second pin 52, respectively, and the second secondary winding unit 22b is connected to the second pin 52 and the third pin 53, respectively.

[0052] The magnetic integrated transformer further includes a bottom plate 60, and one end of the magnetic core 10 is fixed on the bottom plate 60. The bottom plate 60 can cooperate with a water cooling structure to achieve heat dissipation of the magnetic integrated transformer.

[0053] The magnetic integrated transformer of the present application integrates the function of the resonant inductor in the phase-shifted full-bridge topology with the transformer by arranging a ferrite film 30 between the primary winding 21 and the secondary winding 22, thereby increasing the leakage inductance of the magnetic integrated transformer, and being able to maintain a large resonant inductance when lightly loaded to meet the zero voltage opening of the lagging bridge arm during the switching process, thereby reducing switching losses and improving conversion efficiency. As the load increases, the resonant inductance decays, avoiding the problem of loss of the secondary side duty cycle when the load increases, so that the magnetic integrated transformer can maintain efficient and stable operation.

[0054] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without causing conflicts. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the drawings; all modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of this application should be included in the scope of protection of this application.

Claims

1. A magnetic integrated transformer, characterized in that: It includes a magnetic core and a winding, wherein the magnetic core is provided with a magnetic core center column, the winding is arranged around the magnetic core center column, the winding includes a primary winding and a secondary winding which are stacked, and a ferrite film is arranged between the primary winding and the secondary winding; the ferrite film includes a substrate, a magnetic layer and an adhesive layer which are stacked in sequence, and the adhesive layer is attached to the primary winding or the secondary winding.

2. The magnetic integrated transformer according to claim 1, characterized in that: The area of ​​the ferrite film is adjustable.

3. The magnetic integrated transformer according to claim 1, characterized in that: A spacer is also provided between the primary winding and the secondary winding. The spacer is made of insulating material and has an adjustable thickness.

4. The magnetic integrated transformer according to claim 3, characterized in that: The secondary winding includes a first secondary winding, a second secondary winding, a third secondary winding and a fourth secondary winding arranged in sequence from top to bottom, and the primary winding includes a first primary winding located between the first secondary winding and the second secondary winding and a second primary winding located between the third secondary winding and the fourth secondary winding.

5. The magnetic integrated transformer according to claim 4, characterized in that: The ferrite film is disposed on both sides of the first primary winding and the second primary winding; the spacer is disposed between the first primary winding and the second secondary winding and between the third secondary winding and the second primary winding.

6. The magnetic integrated transformer according to claim 3, characterized in that: The spacer includes at least one of a silicone member, an epoxy board, a DuPont paper, and a ceramic sheet.

7. The magnetic integrated transformer according to claim 1, characterized in that: The number of the primary windings and the number of the secondary windings are both several, each of the secondary windings includes a first secondary winding unit and a second secondary winding unit, and each of the primary windings includes a primary winding unit; the first secondary winding unit and the second secondary winding unit each include two layers of secondary winding layers connected in parallel, and the primary winding unit includes two layers of primary winding layers connected in parallel.

8. The magnetic integrated transformer according to claim 7, characterized in that: The magnetically integrated transformer also includes pins connected to the secondary windings, the pins including a first pin, a second pin and a third pin arranged perpendicular to the windings, one group of secondary windings in each of the secondary windings is respectively connected to the first pin and the second pin, and the other group of secondary windings is respectively connected to the second pin and the third pin.

9. The magnetic integrated transformer according to claim 1, characterized in that: The magnetic core includes a first magnetic core and a second magnetic core that are relatively covered, and the magnetic core center column correspondingly includes a first magnetic core center column and a second magnetic core center column, and the first magnetic core center column and the second magnetic core center column are attached to each other.

10. The magnetic integrated transformer according to claim 1, characterized in that: The primary winding is a coil structure, and the secondary winding is a copper bar structure; the magnetic integrated transformer also includes a bottom plate, and one end of the magnetic core is fixed on the bottom plate.

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