Integrated magnetic component and switching power supply

Abstract

Disclosed in the present application are an integrated magnetic component and a switching power supply. The integrated magnetic component comprises a first circuit board, a second circuit board and a magnet, wherein the first circuit board comprise a primary winding circuit and a secondary winding circuit; the second circuit board comprises a PFC circuit and is arranged side by side with the first circuit board; the magnet comprises a first cavity configured to accommodate the first circuit board and a second cavity configured to accommodate the second circuit board, and the magnet further comprises a partition wall, which is arranged between the first cavity and the second cavity to separate the first cavity from the second cavity.

Description

Integrated magnetic element and switching power supply

[0001] Related applications

[0002] The present application claims priority to the following Chinese patent application:

[0003] Application No. 2024220000041, entitled "Integrated magnetic element and switching power supply", filed on August 16, 2024;

[0004] The above patents are hereby incorporated by reference in their entirety into the present application. TECHNICAL FIELD

[0005] The present application relates to the technical field of switching power supply, and in particular to an integrated magnetic element and switching power supply. BACKGROUND

[0006] At present, switching power supply occupies a dominant position in the power supply field with its high efficiency and high power density. With the development trend of miniaturization of electronic devices, switching power supply also gradually develops towards miniaturization and high power density. As an important component in switching power supply, magnetic element is the main factor affecting the volume and weight of switching power supply, and its design and optimization are of great significance to the power density improvement and structure optimization of switching power supply.

[0007] The magnetic element in the switching power supply includes a transformer, which is configured to realize voltage conversion and electrical isolation. With the increase of output power, the switching power supply needs to set a PFC inductor to reduce harmonics. In the related art, the transformer and the PFC inductor adopt two separate devices, each of which needs independent installation space, resulting in that the magnetic element as a whole occupies a large space, which is difficult to meet the product development needs of compact structure and is not conducive to the improvement of power density. Therefore, a magnetic element structure needs to be developed to meet the development needs of compact switching power supply. SUMMARY

[0008] The embodiments of the present application provide an integrated magnetic element and switching power supply, which can solve the problem that the magnetic element structure in the related art is difficult to be applied to compact switching power supply.

[0009] In a first aspect, the embodiments of the present application provide an integrated magnetic element, which includes a first circuit board, a second circuit board and a magnet. The first circuit board includes a primary winding circuit and a secondary winding circuit. The second circuit board includes a PFC circuit and is arranged side by side with the first circuit board. The magnet includes a first cavity configured to accommodate the first circuit board and a second cavity configured to accommodate the second circuit board. The magnet further includes a partition wall, which is arranged between the first cavity and the second cavity to separate the first cavity from the second cavity.

[0010] In a second aspect, the embodiments of the present application provide a switching power supply, which comprises the integrated magnetic element.

[0011] According to the integrated magnetic element and the switching power supply, the first circuit board and the second circuit board are arranged side by side on the magnetic body, the first circuit board comprises the primary winding circuit and the secondary winding circuit, and is arranged together with the magnetic body as a transformer, the second circuit board comprises the PFC circuit and is arranged together with the magnetic body as a PFC inductor, thus, the transformer and the PFC inductor are integrated into a planar magnetic element, so as to reduce the space occupied by the transformer and the PFC inductor, reduce the overall volume of the magnetic element in the switching power supply, and make the internal structure of the switching power supply more compact, which helps to improve the power density. In the embodiments of the present application, the transformer and the PFC inductor are arranged in two circuit boards respectively, the magnetic body has a partition wall, so that the two circuit boards are arranged in independent spaces respectively, which facilitates maintenance and replacement. In addition, the partition wall provides a common magnetic circuit with low magnetic resistance, so that the magnetic flux generated by the transformer and the magnetic flux generated by the PFC inductor form a loop through the partition wall, the partition wall equivalently increases the effective magnetic conductive area of the magnetic body, so that there are more closed paths of the magnetic flux, and the magnetic flux in the magnetic body is more uniformly distributed, thereby reducing the peak magnetic flux density in the magnetic body, which helps to reduce the working heat of the integrated magnetic element. The decoupling integration is adopted, so that the integrated magnetic element can replace the original two separate magnetic elements, and has little effect on the circuit performance. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0013] FIG. 1 is a perspective structural schematic view of an integrated magnetic element according to an embodiment of the present application;

[0014] FIG. 2 is a perspective exploded structural schematic view of an integrated magnetic element according to an embodiment of the present application;

[0015] FIG. 3 is a sectional view of a magnetic body according to an embodiment of the present application;

[0016] FIG. 4 is a perspective structural schematic view of another integrated magnetic element according to an embodiment of the present application;

[0017] FIG. 5 is a perspective exploded structural schematic view of another integrated magnetic element according to an embodiment of the present application;

[0018] FIG. 6 is a sectional view of another magnetic body according to an embodiment of the present application.

[0019] Reference signs:

[0020] 1, integrated magnetic element; 10, first circuit board; 20, second circuit board; 30, magnet; 11, first pin; 21, second pin; 31, first sub-magnet; 32, second sub-magnet; 33, third sub-magnet; 34, fourth sub-magnet; 35, fifth sub-magnet; 36, magnetic core column; 310, first cavity; 320, second cavity; 301, partition wall; 302, sub-magnetic core column; 311, first magnetic horizontal wall; 312, first magnetic side wall; 321, second magnetic horizontal wall; 331, third magnetic horizontal wall; 332, third magnetic side wall; 341, fourth magnetic horizontal wall; 342, fourth magnetic side wall; 343, first sub-partition wall; 351, fifth magnetic horizontal wall; 352, fifth magnetic side wall; 353, second sub-partition wall; A, first direction; B, second direction. Embodiments of the present application

[0021] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

[0022] Switching power supplies are dominant in the power supply field due to their high efficiency and high power density. In switching power supplies, magnetic elements can achieve energy storage and conversion, filtering, electrical isolation and other functions, but also occupy a large part of the volume space. Generally speaking, the volume of the magnetic element accounts for 20% to 30% of the total volume of the switching power supply, and the weight accounts for 30% to 40% of the total weight of the switching power supply. Therefore, in order to improve the power density, output quality and efficiency of the switching power supply, targeted magnetic element design is needed to reduce the volume and loss of the magnetic element.

[0023] The inventor found that two separate devices are generally used in switching power supplies to achieve PFC (Power factor Correction) inductance and transformers, and the PFC inductor coil and the transformer are separately arranged, each requiring independent installation space, resulting in a large overall space occupied by magnetic elements in the switching power supply. Based on this, the embodiments of the present application propose an integrated magnetic element and a switching power supply.

[0024] As shown in FIG. 1 and FIG. 2, FIG. 1 is a perspective structural schematic diagram of an integrated magnetic element 1 according to an embodiment of the present application, and FIG. 2 is a perspective exploded structural schematic diagram of the integrated magnetic element 1 according to an embodiment of the present application. The integrated magnetic element 1 includes a first circuit board 10, a second circuit board 20 and a magnet 30, and the magnet 30 has magnetism.

[0025] The first circuit board 10 has a multi-layer circuit including a primary winding circuit and a secondary winding circuit, and is arranged in the magnet 30. In the embodiment, the first circuit board 10 and the magnet core 30 are configured as a transformer together. When the first circuit board 10 is connected to a current, the magnetic field generated around the primary winding circuit and the secondary winding circuit interacts with the magnetic field of the magnet 30, thereby playing a role of voltage conversion and electrical isolation.

[0026] In the embodiment, the first circuit board 10 further includes an auxiliary circuit and an electromagnetic interference compensation circuit. The primary winding circuit, the auxiliary circuit, the electromagnetic interference compensation circuit and the secondary winding circuit are arranged in layers in sequence, and the first circuit board 10 is configured to realize circuit connection and power transmission and conversion.

[0027] The second circuit board 20 includes a PFC circuit, and is arranged in the magnet 30. In the embodiment, the second circuit board 20 and the magnet 30 are configured as a PFC inductor together. The PFC circuit includes a PFC inductor coil, and when the second circuit board 20 is connected to a current, the magnetic field generated by the PFC inductor coil interacts with the magnetic field of the magnet 30, thereby improving the power factor of the switching power supply and reducing harmonics.

[0028] Compared with the traditional winding coil, the printed circuit board has small noise, and the winding layer of the printed circuit board has a large heat dissipation area and can withstand a large current density. The flat winding structure is beneficial to reduce the eddy current loss at high frequency. In the embodiment, the first circuit board 10 and the second circuit board 20 are printed circuit boards, and the first circuit board 10 and the second circuit board 20 are in independent spaces in the magnet 30, which is convenient for maintenance. Once a fault occurs, it is easier to locate the specific printed circuit board, and it is also convenient to replace one of the printed circuit boards.

[0029] Please refer to FIG. 1-FIG. 3, FIG. 3 is a cross-sectional view of a magnet 30 in the embodiment, the magnet 30 has a first cavity 310 and a second cavity 320, the first cavity 310 is configured to accommodate the first circuit board 10, and the second cavity 320 is configured to accommodate the second circuit board 20. The first circuit board 10 and the second circuit board 20 are arranged side by side. The edges of the first circuit board 10 and the edges of the second circuit board 20 are correspondingly parallel, and the surfaces of the first circuit board 10 and the second circuit board 20 are parallel or coplanar. The first circuit board 10 and the second circuit board 20 are arranged in a predetermined direction, and the predetermined direction can be the first direction A or the second direction B. In this way, the transformer and the PFC inductor are integrated into a planar magnetic element, reducing the space occupied by the transformer and the PFC inductor, and reducing the number of magnetic elements and the overall volume of the switching power supply, thereby forming a more compact product. In the embodiment, the integrated magnetic element 1 also shortens the wiring length between the transformer and the PFC inductor, and reduces the distribution parameters of the circuit.

[0030] The magnet 30 further comprises a partition wall 301 arranged between the first cavity 310 and the second cavity 320. In the embodiment, the partition wall 301 is arranged to separate the first cavity 310 and the second cavity 320, and the partition wall 301 provides a common magnetic circuit with low magnetic resistance. The magnetic flux generated by the transformer and the magnetic flux generated by the PFC inductor form a magnetic circuit after passing through the partition wall 301, and the coupling between them is small, which has little effect on the circuit performance. It can be understood that the partition wall 301 equivalently increases the effective magnetic area of the magnet 30, so that the magnetic flux closing path is more, and the magnetic flux distribution in the magnet 30 is more uniform, thereby reducing the peak magnetic flux density in the magnet 30, which helps to reduce the working heat of the integrated magnetic element 1.

[0031] In the embodiment, the first cavity 310 and the second cavity 320 respectively penetrate the magnet 30 along a preset direction, which is helpful to form an air duct with smooth airflow, so that the gas can enter the first cavity 310 and the second cavity 320 along the preset direction for heat dissipation. The structure of the first cavity 310 and the second cavity 320 facilitates the pins of the printed circuit board to extend out of the magnet 30, so that the first circuit board 10 and the second circuit board 20 can be electrically connected with the external circuit. The board surface of the first circuit board 10 is parallel to the board surface of the second circuit board 20, the preset direction is perpendicular to the arrangement direction of the first cavity 310 and the second cavity 320, and parallel to the board surface of the first circuit board 10.

[0032] Specifically, the first circuit board 10 comprises a first pin 11 extending out of the magnet 30 from the first cavity 310 and arranged to be electrically connected with the external circuit, and the other part of the first circuit board 10 remains accommodated in the first cavity 310. The second circuit board 20 comprises a second pin 21 extending out of the magnet 30 from the second cavity 320 and arranged to be electrically connected with the external circuit, and the other part of the second circuit board 20 remains accommodated in the second cavity 320. In an optional embodiment of the application, the first pin 11 and the second pin 21 are led out from the same side of the magnet 30, which helps to reduce the wiring length, so that the wiring of the external circuit is more simple, the electromagnetic interference is reduced, and the performance and stability of the circuit are improved.

[0033] In the embodiment, the magnet 30 further comprises a plurality of sub-magnets, which are connected in layers along the first direction A and define the first cavity 310 and the second cavity 320, facilitating disassembly and maintenance.

[0034] It should be noted that the first cavities 310 and the second cavities 320 can be arranged in different directions to adapt to different power supply structures. As shown in FIGS. 1-3, in some embodiments, the plurality of sub-magnets includes a first sub-magnet 31, a second sub-magnet 32, and a third sub-magnet 33 to form the first cavities 310 and the second cavities 320 arranged at intervals along a first direction A, and the structure of the magnet 30 can adapt to a compact power supply. As shown in FIGS. 4-6, FIG. 4 is a perspective view of another integrated magnetic element 1 according to an embodiment of the present application, FIG. 5 is an exploded perspective view of another integrated magnetic element 1 according to an embodiment of the present application, and FIG. 6 is a sectional view of another magnet 30 according to an embodiment of the present application, in other embodiments, the plurality of sub-magnets includes a fourth sub-magnet 34 and a fifth sub-magnet 35 to form the first cavities 310 and the second cavities 320 arranged at intervals along a second direction B, wherein the second direction B is perpendicular to the first direction A, and the structure of the magnet 30 can adapt to a long and thin power supply.

[0035] The magnet 30 further includes two axially parallel magnetic core columns 36, which together with other parts of the magnet 30 form a magnetic circuit. One of the magnetic core columns 36 corresponds to the first cavities 310, and each winding and coil in the first circuit board 10 is sleeved around the periphery of the magnetic core column 36. The other magnetic core column 36 corresponds to the second cavities 320, and the PFC inductor in the second circuit board 20 is sleeved around the periphery of the magnetic core column 36. In the embodiment of the present application, at least one of the plurality of sub-magnets has a magnetic core column 36.

[0036] Further, the sub-magnets have sub-magnetic core columns 302, and the sub-magnetic core columns 302 of two adjacent sub-magnets are oppositely arranged and form a magnetic core column 36, and the two sub-magnetic core columns 302 of the same magnetic core column 36 are coaxial and arranged at intervals. In this way, an air gap is formed between the two sub-magnetic core columns 302 of the same magnetic core column 36 to increase the energy storage capacity of the transformer, reduce the eddy current loss, and improve the energy conversion efficiency. It should be noted that since the partition wall 301 has no air gap, its magnetic resistance is much smaller than that of the magnetic core column 36, so the magnetic flux generated by the transformer and the magnetic flux generated by the PFC inductor will pass through the partition wall 301 to form a magnetic circuit, and the partition wall 301 provides a common magnetic circuit with low magnetic resistance, thereby realizing the decoupling integration of the transformer and the PFC inductor. This magnetic integration can improve the performance of the switching power supply, reduce the input and output current ripple of the switching power supply, and improve the transient response.

[0037] Please continue to refer to FIG. 1-3, in an embodiment of the present application, the plurality of sub-magnets includes a first sub-magnet 31, a second sub-magnet 32 and a third sub-magnet 33, the first sub-magnet 31, the second sub-magnet 32 and the third sub-magnet 33 are sequentially stacked and connected along the first direction A. The first sub-magnet 31 is connected to one side of the second sub-magnet 32, and the first cavity 310 is formed between the first sub-magnet 31 and the second sub-magnet 32. The third sub-magnet 33 is connected to the side of the second sub-magnet 32 away from the first sub-magnet 31, and the second cavity 320 is formed between the second sub-magnet 32 and the third sub-magnet 33. Among them, the first cavity 310 and the second cavity 320 are arranged along the first direction A, so that the first circuit board 10 and the second circuit board 20 are stacked along the first direction A, realizing the maximum degree of compact stacking, higher integration, helping to further improve the power density, suitable for compact structure power supply. It can be seen that in this structure, part of the second sub-magnet 32 forms a partition wall 301.

[0038] Specifically, the first sub-magnet 31 includes a first magnetic transverse wall 311 and two first magnetic side walls 312, and the two first magnetic side walls 312 are arranged on the same side of the first magnetic transverse wall 311. The second sub-magnet 32 includes a second magnetic transverse wall 321, wherein the second magnetic transverse wall 321 forms a partition wall 301. The third sub-magnet 33 includes a third magnetic transverse wall 331 and two third magnetic side walls 332, and the two third magnetic side walls 332 are arranged on the same side of the third magnetic transverse wall 331. Along the first direction A, the two first magnetic side walls 312 are connected to one side of the second magnetic transverse wall 321, and the two third magnetic side walls 332 are connected to the other side of the second magnetic transverse wall 321. Among them, the main wall surface of the first magnetic transverse wall 311, the main wall surface of the second magnetic transverse wall 321 and the main wall surface of the third magnetic transverse wall 331 are perpendicular to the first direction A, so that the first magnetic transverse wall 311, the second magnetic transverse wall 321 and the third magnetic transverse wall 331 are arranged parallel to each other and can be arranged along the first direction A. The first magnetic transverse wall 311 and the second magnetic transverse wall 321 are connected through the two first magnetic side walls 312, and the second magnetic transverse wall 321 and the third magnetic transverse wall 331 are connected through the two third magnetic side walls 332. In this way, a space is formed for accommodating the first circuit board 10 and the second circuit board 20, so that they can be stacked along the first direction A.

[0039] Further, the first sub-magnet 31 further comprises a sub-magnetic core middle column 302, wherein the sub-magnetic core middle column 302 is arranged between the two first magnetic side walls 312, i.e. the first sub-magnet 31 is an "E" type structure, which is simple to assemble. The second sub-magnet 32 further comprises two sub-magnetic core middle columns 302, which are arranged on opposite sides of the second magnetic horizontal wall 321. The third sub-magnet 33 further comprises a sub-magnetic core middle column 302, wherein the sub-magnetic core middle column 302 is arranged between the two third magnetic side walls 332, i.e. the third sub-magnet 33 is an "E" type structure, which is simple to assemble. The sub-magnetic core middle column 302 of the first sub-magnet 31 and one of the sub-magnetic core middle columns 302 of the second sub-magnet 32 are oppositely spaced to form a magnetic core middle column 36, and each winding and coil in the first circuit board 10 is sleeved on the periphery of the magnetic core middle column 36. In this way, an air gap is formed in the magnetic core of the transformer, which helps to reduce the magnetic permeability, increase the saturation current, and increase the ability to store energy. The sub-magnetic core middle column 302 of the third sub-magnet 33 and the other sub-magnetic core middle column 302 of the second sub-magnet 32 are oppositely spaced to form another magnetic core middle column 36, and the PFC inductor coil in the second circuit board 20 is sleeved on the periphery of the magnetic core middle column 36. In this way, an air gap is formed in the magnetic core of the PFC inductor, which helps to reduce the magnetic permeability, increase the saturation current, and increase the ability to store energy.

[0040] In a specific implementation, the structure design of the sub-magnet can be adjusted according to the layout of the printed circuit board, and the relative installation position of the integrated magnetic element 1 can be reasonably arranged. The integrated magnetic element 1 can be vertically installed in the switching power supply, i.e. the first direction A is parallel to the thickness direction of the switching power supply, or can be horizontally installed in the switching power supply, i.e. the first direction A is perpendicular to the thickness direction of the switching power supply.

[0041] Please continue to refer to FIGS. 4-6. In another embodiment of the present application, the plurality of sub-magnets comprises a fourth sub-magnet 34 and a fifth sub-magnet 35, and the fourth sub-magnet 34 and the fifth sub-magnet 35 are connected and jointly define a first cavity 310 and a second cavity 320. The first cavity 310 and the second cavity 320 are arranged in parallel along a second direction B perpendicular to the first direction A, so that the first circuit board 10 and the second circuit board 20 are arranged in parallel along the second direction B. It can be seen that in the projection plane parallel to the plane of the first circuit board 10, the projection area of the magnet 30 is large, which indicates that the heat dissipation area of the magnet 30 is large, and the magnet 30 has good heat dissipation performance and can reduce heat accumulation. In addition, the structure of the magnet 30 is suitable for rectangular flat power supplies.

[0042] The fourth sub-magnet 34 comprises a fourth magnetic transverse wall 341 and two fourth magnetic side walls 342, the two fourth magnetic side walls 342 are arranged on the same side of the fourth magnetic transverse wall 341, and the two fourth magnetic side walls 342 are oppositely arranged along the second direction B. The fifth sub-magnet 35 comprises a fifth magnetic transverse wall 351 and two fifth magnetic side walls 352, the two fifth magnetic side walls 352 are arranged on the same side of the fifth magnetic transverse wall 351, and the two fifth magnetic side walls 352 are oppositely arranged along the second direction B, and the two fourth magnetic side walls 342 and the two fifth magnetic side walls 352 are connected one-to-one. Compared with the scheme that the first circuit board 10 and the second circuit board 20 are stacked along the first direction A, in the embodiment, the first circuit board 10 and the second circuit board 20 are arranged in parallel to the direction of the board surface, the heat dissipation area of the corresponding fourth sub-magnet 34 and fifth sub-magnet 35 is large, the shape of the magnet 30 formed by assembly is more flat, and is suitable for rectangular flat power supply.

[0043] In an embodiment of the present application, the fourth sub-magnet 34 further comprises a first sub-separation wall 343, and the two fourth magnetic side walls 342 are arranged on opposite sides of the first sub-separation wall 343 along the second direction B. The fifth sub-magnet 35 further comprises a second sub-separation wall 353, and the two fifth magnetic side walls 352 are arranged on opposite sides of the second sub-separation wall 353 along the second direction B. Wherein, after the fourth sub-magnet 34 is connected to the fifth sub-magnet 35, the first sub-separation wall 343 and the second sub-separation wall 353 are connected correspondingly, as shown in FIG. 6, one fifth magnetic side wall 352, one fourth magnetic side wall 342, the fourth magnetic transverse wall 341, the first sub-separation wall 343 and the second sub-separation wall 353, and the fifth magnetic transverse wall 351 are sequentially enclosed in a clockwise direction to define a first cavity 310, and the other fifth magnetic side wall, the other fourth magnetic side wall 342, the fourth magnetic transverse wall 341, the first sub-separation wall 343 and the second sub-separation wall 353, and the fifth magnetic transverse wall 351 are sequentially enclosed in a counterclockwise direction to define a second cavity 320. It should be noted that the first sub-separation wall 343 and the second sub-separation wall 353 jointly form a separation wall 301, that is, part of the fourth sub-magnet 34 and part of the fifth sub-magnet 35 form the separation wall 301. Wherein, the separation wall 301 extends along the third direction to form the first cavity 310 and the second cavity 320 spaced apart along the second direction B between the fourth sub-magnet 34 and the fifth sub-magnet 35, and the third direction, the first direction A and the second direction B are perpendicular to each other. In a specific implementation, the height of the first sub-separation wall 343 can be configured to be equal to the height of the two fourth magnetic side walls 342, and the height of the second sub-separation wall 353 can be configured to be equal to the height of the two fifth magnetic side walls 352, so as to facilitate processing and assembly.

[0044] Further, the fourth sub-magnet 34 further comprises two sub-magnetic core middle columns 302, one sub-magnetic core middle column 302 is arranged between each fourth magnetic side wall 342 and the first sub-spacing wall 343, and the fifth sub-magnet 35 further comprises two sub-magnetic core middle columns 302, one sub-magnetic core middle column 302 is arranged between each fifth magnetic side wall 352 and the second sub-spacing wall 353. When the fourth sub-magnet 34 is connected with the fifth sub-magnet 35, each sub-magnetic core middle column 302 of the fourth sub-magnet 34 is arranged in a spaced manner with one sub-magnetic core middle column 302 of the fifth sub-magnet 35 to form a magnetic core middle column 36. In this way, one magnetic core middle column 36 is arranged in each of the first cavity 310 and the second cavity 320, and each winding and coil in the first circuit board 10 is sleeved around the periphery of the magnetic core middle column 36 in the first cavity 310, and the PFC inductor in the second circuit board 20 is sleeved around the periphery of the magnetic core middle column 36 in the second cavity 320, so that the magnetic core of the transformer and the magnetic core of the PFC inductor both form an air gap, which helps to reduce the magnetic permeability, increase the saturation current, and increase the energy storage capacity.

[0045] In another embodiment of the present application, the fourth sub-magnet 34 further comprises a first sub-spacing wall 343, the first sub-spacing wall 343 is arranged between the two fourth magnetic side walls 342, and after each fourth magnetic side wall 342 is connected with one fifth magnetic side wall 352, the first sub-spacing wall 343 abuts against the fifth magnetic transverse wall 351 to form the first cavity 310 and the second cavity 320 between the fourth sub-magnet 34 and the fifth sub-magnet 35. In this embodiment, the structure of the fifth sub-magnet 35 is simpler and easier to cut and form. It can be understood that the height of the first sub-spacing wall 343 is greater than the height of the fourth magnetic side wall 342 along the first direction A, so that the first sub-spacing wall 343 can be attached to and connected to the fifth magnetic transverse wall 351.

[0046] In another embodiment of the present application, the fifth sub-magnet 35 further comprises a second sub-spacing wall 353, the second sub-spacing wall 353 is arranged between the two fifth magnetic side walls 352, and after each fourth magnetic side wall 342 is connected with one fifth magnetic side wall 352, the second sub-spacing wall 353 abuts against the fourth magnetic transverse wall 341 to form the first cavity 310 and the second cavity 320 between the fourth sub-magnet 34 and the fifth sub-magnet 35. In this embodiment, the structure of the fourth sub-magnet 34 is simpler and easier to cut and form. It can be understood that the height of the second sub-spacing wall 353 is greater than the height of the fifth magnetic side wall 352 along the first direction A, so that the second sub-spacing wall 353 can be attached to and connected to the fourth magnetic transverse wall 341.

[0047] For example, in a mobile power supply with an output power of 65W, the integrated magnetic element 1 (including three sub-magnets connected in a stack along the first direction A) of the present application is used to replace the original discrete planar transformer and PFC inductor coil. Under the premise that the overall size of the battery remains unchanged, the original structure can output 65W power, and the replaced structure can output 100W power. The power density is increased from 1.8W / cm 3 to 2.77W / cm 3 , an increase of 53.9%. It can be seen that the integrated magnetic element 1 in the present application can effectively save product space and improve the power density of the product.

[0048] In summary, the present application provides an integrated magnetic element 1 that integrates the transformer and PFC inductor into a planar magnetic element. The maximum working flux density of the integrated magnetic element 1 after integration is less than the sum of the flux densities of each discrete magnetic element (discrete transformer and PFC inductor), reducing the number and volume of magnetic elements in the switching power supply to form a more compact power supply structure and improve its power density. The printed circuit board is used instead of the winding coil to solve the noise problem. In the integrated magnetic element 1 of the present application, the magnet 30 includes a partition wall 301, which forms two magnetic shunts through the partition wall 301 to achieve decoupling integration, which helps to reduce the amount of heat generated. The integrated magnetic element 1 includes two structures, one of which has two printed circuit boards arranged in a stack, and the other has two printed circuit boards arranged in a space, which can adapt to different power supply structures.

[0049] A switching power supply is a high-frequency power conversion device that converts a voltage of one level into a voltage or current required by the user through different architectures.

[0050] The present application also provides a switching power supply comprising the integrated magnetic element 1 described above.

[0051] The switching power supply further comprises an input circuit, an output circuit, a transformer, and a control circuit. The input circuit includes an input filter and an input rectifier. The input filter can eliminate interference from the power grid, and the input rectifier rectifies the input AC power to obtain a relatively smooth DC power and provides it to the transformer. The output circuit includes an output filter and an output rectifier, which provides stable and reliable DC power according to the needs of the load. The control circuit can detect the output DC voltage and compare it with the reference voltage, amplify it, and modulate the pulse width of the oscillator to control the transformer and ensure the stability of the output voltage. In specific implementations, the switching power supply also requires a protection circuit, a synchronous rectification driving circuit, and other auxiliary circuits.

[0052] In the embodiment of the present application, the transformer includes the integrated magnetic element 1. In the switching power supply of the embodiment of the present application, the transformer and the PFC inductor are integrated in the transformer to reduce the volume and loss of the magnetic element, which is conducive to the miniaturization of the transformer and the improvement of the power density of the switching power supply. After the integration of the PFC inductor and the transformer, the relationship between the input and the output is adjusted, and the performance of the transformer is optimized. Optionally, the transformer can be an isolated transformer or a non-isolated transformer.

[0053] The same or similar reference signs in the drawings of the embodiment of the present application correspond to the same or similar components; in the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the positional relationship in the drawings are only used for exemplary illustration, and cannot be understood as a limitation of the present patent, for those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0054] The above only describes the preferred embodiments of the present application and is not intended to limit the present application, any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. An integrated magnetic element, wherein, The integrated magnetic element comprises: a first circuit board comprising a primary winding circuit and a secondary winding circuit; a second circuit board comprising a PFC circuit and arranged side by side with the first circuit board; and a magnet comprising a first cavity configured to accommodate the first circuit board and a second cavity configured to accommodate the second circuit board, and a partition wall arranged between the first cavity and the second cavity to separate the first cavity from the second cavity. The magnet comprises a plurality of sub-magnets stacked along a first direction and defining the first cavity and the second cavity.

2. The integrated magnetic element of claim 1, wherein, The first cavity and the second cavity are arranged in a spaced-apart manner along the first direction.

3. The integrated magnetic element of claim 2, wherein, The plurality of sub-magnets comprises a first sub-magnet, a second sub-magnet and a third sub-magnet stacked along the first direction in sequence, the first sub-magnet and the second sub-magnet defining the first cavity, and the second sub-magnet and the third sub-magnet defining the second cavity. Part of the second sub-magnet forms the partition wall.

4. The integrated magnetic element of claim 3, wherein the first sub-magnet comprises a first magnetic transverse wall and two first magnetic side walls arranged on the same side of the first magnetic transverse wall; the second sub-magnet comprises a second magnetic transverse wall; the third sub-magnet comprises a third magnetic transverse wall and two third magnetic side walls arranged on the same side of the third magnetic transverse wall; along the first direction, the two first magnetic side walls are connected to one side of the second magnetic transverse wall, and the two third magnetic side walls are connected to the other side of the second magnetic transverse wall; the second magnetic transverse wall forms the partition wall. The first cavity and the second cavity are arranged in a spaced-apart manner along a second direction perpendicular to the first direction.

5. The integrated magnetic element of claim 2, wherein, The plurality of sub-magnets comprises a fourth sub-magnet and a fifth sub-magnet, the fourth sub-magnet and the fifth sub-magnet being connected and jointly defining the first cavity and the second cavity. Part of the fourth sub-magnet and / or part of the fifth sub-magnet forms the partition wall.

6. The integrated magnetic element of claim 5, wherein the fourth sub-magnet comprises a fourth magnetic transverse wall, a first partition wall arranged on the same side of the fourth magnetic transverse wall, and two fourth magnetic side walls arranged on opposite sides of the first partition wall along the second direction; the fifth sub-magnet comprises a fifth magnetic transverse wall, a second partition wall arranged on the same side of the fifth magnetic transverse wall, and two fifth magnetic side walls arranged on opposite sides of the second partition wall along the second direction; wherein the two fourth magnetic side walls and the two fifth magnetic side walls are connected in a one-to-one correspondence, and the first partition wall and the second partition wall are connected and jointly form the partition wall.

7. The integrated magnetic element of claim 5, wherein the fourth sub-magnet comprises a fourth magnetic transverse wall, a first partition wall arranged on the same side of the fourth magnetic transverse wall, and two fourth magnetic side walls arranged on opposite sides of the first partition wall along the second direction; ​ The fifth sub-magnet comprises a fifth magnetic transverse wall and two fifth magnetic side walls arranged on the same side of the fifth magnetic transverse wall, and the two fifth magnetic side walls are oppositely arranged along the second direction; Each fourth magnetic side wall is connected with a fifth magnetic side wall, and the first sub-spacer abuts against the fifth magnetic transverse wall.

8. The integrated magnetic element of claim 5, wherein, The fourth sub-magnet comprises a fourth magnetic transverse wall and two fourth magnetic side walls arranged on the same side of the fourth magnetic transverse wall, and the two fourth magnetic side walls are oppositely arranged along the second direction; The fifth sub-magnet comprises a fifth magnetic transverse wall, a second sub-spacer wall arranged on the same side of the fifth magnetic transverse wall, and two fifth magnetic side walls oppositely arranged on the two sides of the second sub-spacer wall along the second direction; Each fourth magnetic side wall is connected with a fifth magnetic side wall, and the second sub-spacer abuts against the fourth magnetic transverse wall.

9. The integrated magnetic element of claim 2, wherein, The magnet further comprises two axially parallel magnetic core columns, one of which is arranged corresponding to the first cavity and the first circuit board is sleeved on the periphery of the magnetic core column, and the other of which is arranged corresponding to the second cavity and the second circuit board is sleeved on the periphery of the magnetic core column; At least one of the plurality of sub-magnets has the magnetic core column.

10. The integrated magnetic element of claim 7, wherein, Each sub-magnet has a sub-magnetic core column, and the sub-magnetic core columns of two adjacent sub-magnets are oppositely arranged and form a magnetic core column, and the two sub-magnetic core columns of the same magnetic core column are coaxially and spaced apart.

11. The integrated magnetic element of claim 1, wherein, The board surface of the first circuit board is parallel to the board surface of the second circuit board. The first cavity and the second cavity respectively penetrate the magnet along a preset direction, and the preset direction is perpendicular to the arrangement direction of the first cavity and the second cavity and parallel to the board surface of the first circuit board.

12. The integrated magnetic element of claim 11, wherein, The first circuit board comprises first pins, and the second circuit board comprises second pins, and the first pins and the second pins are led out on the same side of the magnet to be electrically connected with external circuits.

13. The integrated magnetic element of claim 1, wherein, The first circuit board further comprises an auxiliary circuit and an electromagnetic interference compensation circuit, and the primary winding circuit, the auxiliary circuit, the electromagnetic interference compensation circuit, and the secondary winding circuit are sequentially stacked.

14. The integrated magnetic element of claim 1, wherein, The first circuit board and the second circuit board are both printed circuit boards.

15. A switched mode power supply wherein, The integrated magnetic element comprises: A first circuit board comprising a primary winding circuit and a secondary winding circuit; A second circuit board comprising a PFC circuit and arranged side by side with the first circuit board; and A magnet comprising a first cavity arranged to accommodate the first circuit board and a second cavity arranged to accommodate the second circuit board, and further comprising a spacer wall arranged between the first cavity and the second cavity to separate the first cavity from the second cavity.

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