LLC magnetic integrated transformer

Abstract

The utility model discloses an LLC magnetic integrated transformer, which belongs to the technical field of transformers and comprises a primary coil, a secondary coil and a magnetic core. The magnetic core comprises a first magnetic column, a second magnetic column, a third magnetic column, a fourth magnetic column and a magnetic core cross beam; the primary coil is wound on the surface of the first magnetic column, and the secondary coil is simultaneously wound on the surfaces of the first magnetic column and the fourth magnetic column; according to the LLC magnetic integrated transformer provided by the utility model, a flat transformer structure is adopted, and the primary coil and the secondary coil are wound on the first magnetic column and the fourth magnetic column, so that integration of a resonant inductor and the transformer in an LLC power supply is realized, and the requirements of the transformer and the resonant inductor can be met by only one magnetic core; moreover, the structure has a good heat dissipation effect, and the miniaturization of the power supply is facilitated.

Description

Technical Field

[0001] The utility model belongs to the technical field of transformers, and particularly relates to an LLC magnetically integrated transformer. Background Art

[0002] A transformer is a core component of a power system and electronic equipment. It can achieve energy transfer through the principle of electromagnetic induction, and at the same time, completely separate the input circuit (primary winding) and the output circuit (secondary winding) electrically. An LLC (resonant converter) power supply requires a resonant inductor and a transformer, which are usually composed of multiple magnetic components. However, due to the requirement of high power density, it is difficult to assemble multiple discrete components. Therefore, an integrated design of multiple magnetic components is required. Content of the Utility Model

[0003] Aiming at the problems existing in the prior art, the utility model provides an LLC magnetically integrated transformer, which specifically includes: a primary coil, a secondary coil and a magnetic core. The magnetic core includes a first magnetic column, a second magnetic column, a third magnetic column, a fourth magnetic column and a magnetic core cross beam, wherein the second magnetic column and the third magnetic column are symmetrically distributed.

[0004] Preferably, the second magnetic column and the third magnetic column are respectively distributed at the left and right ends of the first magnetic column, and the fourth magnetic column is located at the upper end of the first magnetic column.

[0005] Preferably, the first magnetic column is used as a transformer, and the fourth magnetic column is used as a resonant inductor. Increasing or decreasing the air gap of the first magnetic column can adjust the exciting inductance value of the transformer, while increasing or decreasing the air gap of the fourth magnetic column can adjust the resonant inductance value. The first magnetic column, the second magnetic column, the third magnetic column, the fourth magnetic column and the magnetic core cross beam jointly form a closed magnetic circuit, and the magnetic flux in this closed magnetic circuit is the vector sum of the magnetic fluxes generated by the transformer and the resonant inductor.

[0006] Based on the above technical features, in this solution, the magnetically integrated magnetic core can use a PCB board as the transformer winding, or directly use a coil wound on the magnetic core as the transformer winding.

[0007] Preferably, the winding methods of the primary coil and the secondary coil are as follows:

[0008] The primary coil is wound on the surface of the first magnetic column, and the secondary coil is wound on the surfaces of the first magnetic column and the fourth magnetic column at the same time, that is, in space, the secondary coil includes the first magnetic column and the fourth magnetic column.

[0009] Preferably, the transformer adopts a flat structure.

[0010] Preferably, a heat dissipation channel is arranged inside the transformer. It is located between the first magnetic column and the second magnetic column, and between the first magnetic column and the third magnetic column.

[0011] Based on the above technical features, the transformer adopts a flat structure, with heat dissipation channels designed inside. It can be naturally air-cooled at low power, and can dissipate heat by using external heat sinks or air-cooling at high power.

[0012] Preferably, the first magnetic column, the second magnetic column, the third magnetic column, and the fourth magnetic column are provided with different cross-sectional area ratios.

[0013] Based on the above technical features, by controlling the cross-sectional area ratios of the four magnetic columns and the number of primary and secondary coils, the resonant inductance value of the LLC power supply and the excitation inductance value of the transformer can be accurately adjusted to adapt to the precise control of the resonant frequency of the LLC power supply (a temperature change of 25 - 100 °C will cause a deviation of about 5%).

[0014] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0015] An LLC magnetic integrated transformer proposed by the present utility model adopts a flat transformer structure, with the primary coil and the secondary coil wound around the first magnetic column and the fourth magnetic column, realizing the integration of the resonant inductor and the transformer in the LLC power supply. Only one magnetic core is needed to meet the requirements of the transformer and the resonant inductor, reducing the volume of the power supply, increasing the power density of the power supply, and having a good heat dissipation effect in structure; the proposed LLC magnetic integrated transformer structure can meet the application requirements of high-power power supplies;

[0016] In this solution, the magnetic integrated magnetic core can use a PCB board as the transformer winding, or directly use a coil wound around the magnetic core as the transformer winding. By controlling the cross-sectional area ratios of the four magnetic columns and the number of primary and secondary coils, the resonant inductance value of the LLC power supply and the excitation inductance value of the transformer can be accurately adjusted to adapt to the precise control of the resonant frequency of the LLC power supply; the transformer adopts a flat structure, with heat dissipation channels designed inside. It can be naturally air-cooled at low power, and can dissipate heat by using external heat sinks or air-cooling at high power, which can meet the requirements of miniaturization and high power density of the LLC power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is an exploded structural schematic diagram of the LLC magnetic integrated transformer provided by an embodiment of the present utility model;

[0018] Figure 2 is an exploded structural schematic diagram of the magnetic core provided by an embodiment of the present utility model;

[0019] Figure 3 is a front view of the overall structure of the magnetic core provided by an embodiment of the present utility model;

[0020] Figure 4 is a rear view of the overall structure of the magnetic core provided by an embodiment of the present utility model;

[0021] Figure 5 It is a schematic diagram of the specific implementation of the LLC magnetic integrated transformer provided by the embodiment of the present utility model;

[0022] Figure 6 It is a schematic diagram of the equivalent circuit of the LLC magnetic integrated transformer provided by the embodiment of the present utility model.

[0023] List of attached drawing reference signs: the first magnetic column 1, the second magnetic column 2, the third magnetic column 3, the fourth magnetic column 4, the magnetic core crossbeam 5, the primary coil 6, the secondary coil 7. Specific implementation

[0024] The following further clarifies the present utility model in conjunction with the attached drawings and specific implementation manners. It should be understood that the following specific implementation manners are only used to illustrate the present utility model and not to limit the scope of the present utility model.

[0025] Embodiment: A kind of LLC magnetic integration technical solution provided by the present utility model integrates the resonant inductor and the transformer in the LLC power supply; wherein Figure 5 and Figure 6 In, a is the first end point of the magnetic integrated transformer, b is the second end point of the magnetic integrated transformer, c is the third end point of the magnetic integrated transformer, d is the fourth end point of the magnetic integrated transformer, and e is the fifth end point of the magnetic integrated transformer. The first end point a and the second end point b are located on the primary side of the magnetic integrated transformer, while the third end point c, the fourth end point d, and the fifth end point e are located on the secondary side of the magnetic integrated transformer, where the fourth end point d is the center tap end point on the secondary side of the magnetic integrated transformer.

[0026] As Figures 1 to 4 shown, the magnetic core structure includes the first magnetic column 1, the second magnetic column 2, the third magnetic column 3, the fourth magnetic column 4, and the magnetic core crossbeam 5. The second magnetic column 2 and the third magnetic column 3 are placed left and right relative to the first magnetic column 1 and are symmetrically distributed; the fourth magnetic column 4 is placed directly in front of the first magnetic column 1, which is easy to wind the coil and leaves space for air circulation, thereby increasing the heat dissipation effect. The first magnetic column 1 is used as a transformer, and the fourth magnetic column 4 is used as a resonant inductor. Increasing or decreasing the air gap of the first magnetic column 1 can adjust the exciting inductance value of the transformer, and increasing or decreasing the air gap of the fourth magnetic column 4 can adjust the resonant inductance value. The first magnetic column 1, the second magnetic column 2, the third magnetic column 3, the fourth magnetic column 4, and the magnetic core crossbeam 5 together form a closed magnetic circuit, and the magnetic flux in this closed magnetic circuit is the vector sum of the magnetic fluxes generated by the transformer and the resonant inductor. The primary coil and the secondary coil are wound on the first magnetic column 1 and the fourth magnetic column 4, realizing the integration of the resonant inductor and the transformer in the LLC power supply. Only one magnetic core is needed to meet the requirements of the transformer and the resonant inductor, reducing the volume of the power supply, increasing the power density of the power supply, and having a good heat dissipation effect in terms of structure.

[0027] See Figure 1 、 Figure 5and Figure 6 , the first magnetic post 1 and the fourth magnetic post 4 are used for winding coils. The winding method is as follows: the primary coil 6 is wound on the surface of the first magnetic post 1, and the secondary coil 7 is wound on the surfaces of the first magnetic post 1 and the fourth magnetic post 4 simultaneously, that is, in space, the secondary coil 7 includes the first magnetic post 1 and the fourth magnetic post 4; the adopted LLC transformer magnetic integration scheme integrates the resonant inductor Lr and the exciting inductor Lm, and can meet the application requirements of high-power power supplies.

[0028] In this scheme, the LLC magnetic integration transformer can accurately adjust the resonant inductor value of the LLC power supply and the exciting inductor value of the transformer by controlling the cross-sectional area ratio of the first magnetic post 1, the second magnetic post 2, the third magnetic post 3 and the fourth magnetic post 4 and the number of primary and secondary coils, so as to adapt to the accurate control of the resonant frequency of the LLC power supply (a temperature change of 25 - 100 °C will cause a deviation of about 5%); the transformer adopts a flat structure, and there is a heat dissipation channel designed inside it. It can be naturally air-cooled at low power, and can be cooled by using an externally added heat sink or air-cooling at high power, and can meet the requirements of miniaturization and high power density of the LLC power supply.

[0029] It should be noted that the above content only illustrates the technical idea of the present utility model, and cannot be used to limit the protection scope of the present utility model. For those of ordinary skill in the art of this technology, without departing from the principle of the present utility model, several improvements and retouches can still be made, and these improvements and retouches all fall within the protection scope of the claims of the present utility model.

Claims

1. An LLC magnetic integrated transformer, characterized in that: The invention comprises a primary coil (6), a secondary coil (7) and a magnetic core, wherein the magnetic core comprises a first magnetic column (1), a second magnetic column (2), a third magnetic column (3), a fourth magnetic column (4) and a magnetic core cross beam (5), wherein the first magnetic column (1), the second magnetic column (2), the third magnetic column (3), the fourth magnetic column (4) and the magnetic core cross beam (5) together form a closed magnetic circuit, wherein the first magnetic column (1) is used as a transformer, and the fourth magnetic column (4) is used as a resonant inductor, wherein the primary coil (6) and the secondary coil (7) are wound on the first magnetic column (1) and the fourth magnetic column (4), wherein the primary coil (6) is wound on the surface of the first magnetic column (1), and the secondary coil (7) is wound on the surfaces of the first magnetic column (1) and the fourth magnetic column (4) at the same time, and the secondary coil (7) spatially contains the first magnetic column (1) and the fourth magnetic column (4).

2. The LLC magnetic integrated transformer according to claim 1, characterized in that: The fourth magnetic column (4) is located at the upper end of the first magnetic column (1).

3. The LLC magnetic integrated transformer according to claim 1, characterized in that: The second magnetic columns (2) and the third magnetic columns (3) are symmetrically distributed.

4. The LLC magnetic integrated transformer according to claim 3, characterized in that: The second magnetic column (2) and the third magnetic column (3) are respectively distributed at the left and right ends of the first magnetic column (1).

5. The LLC magnetic integrated transformer according to claim 1, characterized in that: The transformer adopts a flat structure.

6. The LLC magnetic integrated transformer according to claim 1, characterized in that: A heat dissipation channel is provided inside the transformer and is located between the first magnetic column (1) and the second magnetic column (2), and between the first magnetic column (1) and the third magnetic column (3).

7. The LLC magnetic integrated transformer according to claim 1, characterized in that: The first magnetic column (1), the second magnetic column (2), the third magnetic column (3), and the fourth magnetic column (4) are provided with different cross-sectional area ratios.

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