Inductance and electrical equipment

Abstract

The application discloses an inductor and an electrical device, and belongs to the technical field of inductors. The inductor comprises a first magnetic core, a second magnetic core, a coil and a magnetic sheet. The second magnetic core comprises a magnetic core substrate, a first magnetic column and a second magnetic column. The magnetic core substrate and the first magnetic core are spaced apart along a first direction. The first magnetic column and the second magnetic column are spaced apart along a second direction. The first magnetic column, the second magnetic column and the magnetic core substrate form a containing space. The second magnetic column is connected with the first magnetic core, and an air gap is formed between the first magnetic column and the first magnetic core. The coil is installed in the containing space and wound around the second magnetic column. The magnetic sheet is arranged between the first magnetic column and the second magnetic column. The distance between the magnetic sheet and the first magnetic column is smaller than the distance between the magnetic sheet and the second magnetic column. The distance between the magnetic sheet and the first magnetic column is smaller than the distance between the coil and the first magnetic column. The distance between the magnetic sheet and the first magnetic core is smaller than the distance between the coil and the first magnetic core. The magnetic sheet can absorb and guide the scattered magnetic flux diffused outward at the air gap, so that the loss of the coil can be reduced.

Description

Technical Field

[0001] This application belongs to the field of inductor technology, and particularly relates to an inductor and electrical device. Background Technology

[0002] Planar inductors are widely used in various electronic devices such as switching power supplies and power conversion modules due to their advantages of small size, low height, and ease of integration. In related technologies, planar inductors typically consist of two magnetic cores and a coil, with an air gap between the two cores to adjust the inductance and prevent core saturation. However, magnetic flux diffuses at the air gap, and some of the diffused flux cuts through the coil conductor, generating eddy currents within the conductor. This leads to a significant increase in copper losses in the coil, indicating room for improvement. Summary of the Invention

[0003] This application aims to at least solve one of the technical problems existing in the prior art. To this end, this application proposes an inductor and electrical device that can reduce coil losses.

[0004] Firstly, this application provides an inductor.

[0005] Inductors are used in electrical equipment, including: First magnetic core; The second magnetic core includes a magnetic core substrate, a first magnetic post and a second magnetic post. The magnetic core substrate and the first magnetic core are spaced apart along a first direction. The first magnetic post and the second magnetic post are spaced apart along a second direction. An accommodating space is formed between the first magnetic post, the second magnetic post and the magnetic core substrate. The second magnetic post and the first magnetic core are connected. An air gap is formed between the first magnetic post and the first magnetic core. A coil is installed within the accommodating space and wound around the second magnetic post; A magnetic sheet is disposed between the first magnetic post and the second magnetic post. The distance between the magnetic sheet and the first magnetic post is less than the distance between the magnetic sheet and the second magnetic post. The distance between the magnetic sheet and the first magnetic post is less than the distance between the coil and the first magnetic post. The distance between the magnetic sheet and the first magnetic core is less than the distance between the coil and the first magnetic core.

[0006] According to the inductor of this application, by absorbing and guiding the diffuse magnetic flux that diffuses outward from the air gap through the magnetic sheet, the amount of diffuse magnetic flux passing through the coil can be reduced, the degree of cutting of the coil conductor by the diffuse magnetic flux can be reduced, thereby reducing the coil loss.

[0007] According to one embodiment of this application, the magnetic reluctance of the air gap is Rg, the magnetic reluctance between the side of the magnetic sheet facing the first magnetic post and the first magnetic post is R1, and the magnetic reluctance between the side of the magnetic sheet facing the coil and the first magnetic post is R2, satisfying: Rg < R1 < R2.

[0008] According to one embodiment of this application, the distance between the magnetic sheet and the first magnetic post along the second direction is d1, and the distance between the side of the magnetic sheet facing the coil and the first magnetic post is d2, satisfying: d2 > 1.5d1.

[0009] According to one embodiment of this application, ; Wherein, b is the width of the side of the magnetic sheet facing the coil along the second direction.

[0010] According to one embodiment of this application, the magnetic sheet comprises multiple segments, at least a portion of which is located on the side of the coil facing the first magnetic post.

[0011] According to one embodiment of this application, the length of the magnetic sheet along a third direction is the same as the length of the first magnetic post along the third direction, and the first direction, the second direction, and the third direction intersect each other.

[0012] According to one embodiment of this application, the projection of the magnetic sheet along the first direction at least partially coincides with the projection of the coil along the first direction.

[0013] According to one embodiment of this application, ; Where R is the magnetic resistance between the side of the magnetic sheet facing the first magnetic post and the first magnetic post, d is the distance between the magnetic sheet and the first magnetic post along the second direction, μ is the permeability of free space, and Aecp is the surface area of ​​the side of the magnetic sheet facing the first magnetic post.

[0014] According to one embodiment of this application, ; Wherein, R is the magnetic resistance between the side of the magnetic sheet facing the coil and the first magnetic post, d is the distance along the second direction between the side of the magnetic sheet facing the coil and the first magnetic post, μ is the permeability of free space, and Aecp is the surface area of ​​the side of the magnetic sheet facing the coil.

[0015] Secondly, this application provides an electrical device including the inductor described in any one of the above-mentioned methods.

[0016] According to the electrical device of this application, by using the aforementioned inductor, the scattered magnetic flux passing through the coil can be reduced, thereby reducing coil losses.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is one of the structural schematic diagrams of the inductor provided in the embodiments of this application; Figure 2 This is a second schematic diagram of the structure of the inductor provided in the embodiments of this application; Figure 3 This is the third schematic diagram of the structure of the inductor provided in the embodiments of this application; Figure 4 This is the fourth schematic diagram of the structure of the inductor provided in the embodiments of this application; Figure 5 This is the fifth schematic diagram of the structure of the inductor provided in the embodiments of this application; Figure 6 This is the sixth schematic diagram of the structure of the inductor provided in the embodiments of this application; Figure 7 This is the seventh schematic diagram of the structure of the inductor provided in the embodiments of this application.

[0019] Figure label: 1. Inductor; 10. First magnetic core; 20. Second magnetic core; 210. First magnetic post; 220. Second magnetic post; 230. Magnetic core substrate; 30. Air gap; 40. Coil; 50. Magnetic sheet; Z, First direction; Y, Second direction; X, Third direction. Detailed Implementation

[0020] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0021] This application aims to at least solve one of the technical problems existing in the prior art. To this end, this application proposes an inductor and electrical device that can reduce coil losses.

[0022] The following is for reference. Figures 1-7 Inductor 1 according to an embodiment of this application is described.

[0023] like Figure 1As shown, the inductor 1 includes a first magnetic core 10, a second magnetic core 20, a coil 40, and a magnetic sheet 50. The second magnetic core 20 includes a core substrate 230, a first magnetic post 210, and a second magnetic post 220. The core substrate 230 and the first magnetic core 10 are spaced apart along a first direction, and the first magnetic post 210 and the second magnetic post 220 are spaced apart along a second direction. An accommodating space is formed between the first magnetic post 210, the second magnetic post 220, and the core substrate 230. The second magnetic post 220 is connected to the first magnetic core 10, and an air gap 30 is formed between the first magnetic post 210 and the first magnetic core 10. The coil 40 is mounted in the accommodating space and wound around the second magnetic post 220. The magnetic sheet 50 is disposed between the first magnetic post 210 and the second magnetic post 220. The distance between the magnetic sheet 50 and the first magnetic post 210 is less than the distance between the magnetic sheet 50 and the second magnetic post 220. The distance between the magnetic sheet 50 and the first magnetic post 210 is less than the distance between the coil 40 and the first magnetic post 210. The distance between the magnetic sheet 50 and the first magnetic core 10 is less than the distance between the coil 40 and the first magnetic core 10.

[0024] In this embodiment, inductor 1 includes, but is not limited to, planar inductor 1.

[0025] This application does not impose specific limitations on the shape of the inductor 1 or the shapes of the magnetic core and magnetic pillars. The inductor 1 can have various shapes. For example, the first magnetic core 10 and the magnetic core substrate 230 can be set as rectangular or nearly rectangular plate structures. In this case, the first magnetic pillar 210 can be set as a magnetic pillar with a rectangular cross-section, and the magnetic sheet 50 is a long straight strip. In another example, the first magnetic core 10 and the magnetic core substrate 230 can be set as circular or nearly circular plate structures. The cross-section of the first magnetic pillar 210 is annular or a partially annular shape. The first magnetic pillar 210 has the central axis of the second magnetic pillar 220 as its axis. In this case, the magnetic sheet 50 can be annular or arc-shaped thin sheet. The second direction Y between the first magnetic pillar 210 and the second magnetic pillar 220 is the radial direction of the circle, and the length extension direction of the first magnetic pillar 210 is the circumferential direction of the circle.

[0026] For ease of understanding, the following embodiments and accompanying drawings use a rectangular inductor 1 as an example to describe the solution of this application, with Z as the first direction, Y as the second direction, and X as the third direction in the drawings.

[0027] The first magnetic core 10 and the second magnetic core 20 of the inductor 1 are distributed along the first direction Z, and at least a portion of the second magnetic core 20 is spaced apart from the first magnetic core 10 along the first direction Z, forming an air gap 30 at the gap. The air gap 30 is mainly used to adjust the inductance to prevent the magnetic core from saturating under high current conditions. In other words, introducing the air gap 30 into the magnetic circuit can reduce the effective permeability of the magnetic core, while the presence of the air gap 30 allows the magnetic core to withstand a larger DC bias current without entering a saturation state.

[0028] The first magnetic core 10 includes, but is not limited to, a planar magnetic core, and the second magnetic core 20 includes, but is not limited to, an E-shaped magnetic core. Specifically, the second magnetic core 20 may include a magnetic core substrate 230 and a first magnetic post 210 and a second magnetic post 220 extending from the magnetic core substrate 230 along a first direction Z. The magnetic core substrate 230 and the first magnetic core 10 are spaced apart along the first direction Z, the first magnetic post 210 and the first magnetic core 10 are spaced apart along the first direction Z, the second magnetic post 220 and the first magnetic core 10 are connected, and an air gap 30 is formed between the first magnetic post 210 and the first magnetic core 10.

[0029] The first magnetic post 210 and the second magnetic post 220 are spaced apart along the second direction Y. The first magnetic core 10 is disposed on the side of the first magnetic post 210 and the second magnetic post 220 away from the base, and the second magnetic post 220 is located between adjacent first magnetic posts 210 in the second direction Y.

[0030] A receiving space is formed between the first magnetic post 210, the second magnetic post 220, and the magnetic core substrate 230. The coil 40 is installed in the receiving space and wound around the second magnetic post 220. The coil 40 includes, but is not limited to, flat copper wire or PCB, and the number of turns of the coil 40 can be set according to the actual inductance requirements.

[0031] The magnetic sheet 50 is disposed between the first magnetic post 210 and the second magnetic post 220, and is mounted on the side of the coil 40 facing the first magnetic core 10. The distance between the magnetic sheet 50 and the first magnetic post 210 is less than the distance between the magnetic sheet 50 and the second magnetic post 220, meaning the magnetic sheet 50 is generally closer to the first magnetic post 210. The distance between the magnetic sheet 50 and the first magnetic core 10 is less than the distance between the coil 40 and the first magnetic core 10, meaning the magnetic sheet 50 is disposed between the coil 40 and the first magnetic core 10. The magnetic sheet 50 is located near the air gap 30, with a gap between it and the air gap 30, and the magnetic sheet 50 is not filled inside the air gap 30.

[0032] The magnetic sheet 50 has a first surface facing the first magnetic post 210 and a second surface facing the coil 40. The vertical distance from the first surface of the magnetic sheet 50 to the first magnetic post 210 is less than the vertical distance from the coil 40 to the first magnetic post 210, that is, the distance between the magnetic sheet 50 and the first magnetic post 210 is less than the distance between the coil 40 and the first magnetic post 210.

[0033] At least a portion of the coil 40 is located between the first magnetic post 210 and the second magnetic post 220, and the air gap 30 is located between the first magnetic post 210 and the first magnetic core 10. In the inductor 1, the main magnetic circuit consists of the first magnetic core 10, the air gap 30, and the second magnetic core 20. When current flows through the planar inductor 1, a main magnetic flux is generated in the magnetic core. The main magnetic flux travels along one of the first magnetic posts 210, through the air gap 30, to the first magnetic core 10, and then returns to the second magnetic core 20 via the other first magnetic post 210, forming a closed magnetic circuit. However, due to the edge magnetic flux effect at the air gap 30, some magnetic flux diffuses outward from the edge of the air gap 30, forming scattered magnetic flux. Without the magnetic sheet 50, the portion of the coil 40 near the air gap 30 is easily cut by the scattered magnetic flux. The scattered magnetic flux cuts the conductor of the coil 40, inducing eddy currents in the conductor and generating significant eddy current losses.

[0034] Both the magnetic sheet 50 and the magnetic core are made of magnetic materials with a relative permeability greater than that of air. The magnetic sheet 50 is located between the coil 40 and the air gap 30. When the scattered magnetic flux at the air gap 30 diffuses toward the coil 40, it is preferentially absorbed by the magnetic sheet 50, which helps to reduce the scattered magnetic flux passing through the coil 40, thereby reducing the loss of the coil 40.

[0035] For example, the magnetic sheet 50 and the magnetic core can be made of ferrite material, metal magnetic powder core material or other suitable soft magnetic material.

[0036] It should be noted that the magnetic sheet 50 is located between the coil 40 and the air gap 30, that is, the magnetic sheet 50 is spatially located between the coil 40 and the air gap 30. At the same time, the magnetic reluctance of the magnetic circuit corresponding to the first side of the magnetic sheet 50 is less than the magnetic reluctance of the magnetic circuit corresponding to the second side of the magnetic sheet 50. The scattered magnetic flux at the air gap 30 follows the path with lower magnetic reluctance, thereby realizing the directional guidance of the scattered magnetic flux by the magnetic sheet 50.

[0037] The magnetic reluctance of the air gap 30 is less than the magnetic reluctance of the magnetic circuit corresponding to the first surface of the magnetic sheet 50, and the magnetic reluctance of the magnetic circuit corresponding to the first surface of the magnetic sheet 50 is less than the magnetic reluctance of the magnetic circuit corresponding to the second surface of the magnetic sheet 50. When the scattered magnetic flux passes through the magnetic circuit corresponding to the second surface of the magnetic sheet 50, it will cut the coil 40, but when the scattered magnetic flux passes through the magnetic circuit corresponding to the first surface of the magnetic sheet 50, it will not cut the coil 40.

[0038] Planar inductors are widely used in various electronic devices such as switching power supplies and power conversion modules due to their advantages of small size, low height, and ease of integration. A planar inductor consists of two magnetic cores and a coil, with an air gap between the two cores to adjust the inductance and prevent core saturation. However, magnetic flux diffuses at the air gap, and some of this diffused flux cuts through the coil conductor, generating eddy currents within the conductor. This significantly increases the copper losses of the coil, indicating room for improvement.

[0039] To reduce coil losses caused by air gap demagnetization, various solutions have been proposed in related technologies. Some solutions divide a single air gap into multiple segmented air gaps using air gap partitions to reduce the influence range of edge magnetic flux. However, this mainly improves the magnetic field distribution by increasing the number of air gaps, with limited improvement and no ability to absorb demagnetizing flux. Some solutions reduce the inductance of high-frequency planar inductors to make losses controllable, but this solution is not suitable for inductors with large inductance. Some solutions move the copper wire away from the air gap to reduce copper losses, but this occupies the height space of the magnetic components, and the larger the air gap, the greater the distance between the copper wire and the air gap needs to be, resulting in poor space utilization. Other solutions use multi-strand stranded wire to reduce copper losses; however, multi-strand stranded wire is expensive, has high DC resistance, and the presence of stranding gaps leads to a low fill rate, requiring a larger winding window.

[0040] This application can effectively reduce the losses caused by the magnetic flux dispersion in the air gap 30 to the coil 40 without significantly increasing the space occupation. A magnetic sheet 50 is provided on the side of the coil 40 facing the first magnetic core 10, and the magnetic sheet 50 covers the portion of the coil 40 cut by the magnetic flux dispersion. The magnetic sheet 50 is made of a high permeability material, so the magnetic flux dispersion experiences less magnetic resistance when passing through the magnetic sheet 50. When the magnetic flux dispersion diffuses outward, it will preferentially choose the path of the magnetic sheet 50 with lower magnetic resistance. Most of the magnetic flux dispersion is absorbed by the magnetic sheet 50 and guided to the path of the magnetic sheet 50, thereby reducing the amount of magnetic flux dispersion passing through the coil 40, reducing the degree to which the conductor of the coil 40 is cut by the magnetic flux dispersion, and thus reducing eddy current losses.

[0041] According to the inductor 1 provided in the embodiment of this application, the magnetic sheet 50 absorbs and guides the outward diffusion of the magnetic flux at the air gap 30, which can reduce the amount of magnetic flux passing through the coil 40, reduce the degree of cutting of the conductor of the coil 40 by the magnetic flux, and thus reduce the loss of the coil 40.

[0042] In some embodiments, such as Figure 2 As shown, the magnetic reluctance of the air gap 30 is Rg, the magnetic reluctance between the side of the magnetic sheet 50 facing the first magnetic post 210 and the first magnetic post 210 is R1, and the magnetic reluctance between the side of the magnetic sheet 50 facing the coil 40 and the first magnetic post 210 is R2, satisfying: Rg < R1 < R2.

[0043] In this embodiment, the magnetic reluctance of the air gap 30 is defined as Rg, the magnetic reluctance between the first surface of the magnetic sheet 50 and the first magnetic post 210 is defined as R1, and the magnetic reluctance between the second surface of the magnetic sheet 50 and the first magnetic post 210 is defined as R2, satisfying: Rg < R1 < R2.

[0044] Magnetic reluctance is the degree to which a magnetic circuit impedes magnetic flux, and its basic formula is R = L / (μA). The magnitude of magnetic reluctance depends on the length L of the magnetic circuit, the cross-sectional area A, and the permeability μ of the material.

[0045] The magnetic sheet 50 is made of a high-permeability material, and its own magnetic reluctance is much smaller than that of air. Therefore, the magnetic reluctance between the first surface of the magnetic sheet 50 and the first magnetic post 210 is mainly determined by the air gap between the magnetic sheet 50 and the first magnetic core 10 and the cross-sectional area of ​​the first surface of the magnetic sheet 50. In other words, the magnetic reluctance of the magnetic sheet 50 path can be controlled by adjusting the distance between the magnetic sheet 50 and the first magnetic core 10 and by adjusting the size of the magnetic sheet 50. The larger the ratio of the length L of the magnetic path to the cross-sectional area A, the greater the magnetic reluctance.

[0046] The calculation method for the magnetic reluctance between the second surface of the magnetic sheet 50 and the first magnetic post 210 is the same. Without changing the installation position and size of the coil 40, adjusting the distance between the magnetic sheet 50 and the first magnetic core 10, as well as the size of the magnetic sheet 50, can make the magnetic reluctance between the first surface of the magnetic sheet 50 and the first magnetic post 210 less than the magnetic reluctance between the second surface of the magnetic sheet 50 and the first magnetic post 210, thereby directionally guiding the dissipated magnetic flux and reducing the loss of the coil 40.

[0047] Understandably, with the same magnetic sheet 50 size, the greater the difference between the distance between the first surface of the magnetic sheet 50 and the first magnetic post 210 and the distance between the second surface of the magnetic sheet 50 and the first magnetic post 210, the greater the difference between the magnetic resistance between the first surface of the magnetic sheet 50 and the first magnetic post 210 and the magnetic resistance between the second surface of the magnetic sheet 50 and the first magnetic post 210, and the stronger the effect of the magnetic sheet 50 in directionally guiding the dispersing magnetic flux.

[0048] In addition, such as Figure 3 As shown, the magnetic sheet 50 is spaced apart from the first magnetic core 10, and the magnetic resistance between the magnetic sheet 50 and the first magnetic core 10 is defined as R3.

[0049] The magnetic reluctance of the magnetic circuit corresponding to the first surface of the magnetic sheet 50 is the sum of the magnetic reluctance between the first surface of the magnetic sheet 50 and the first magnetic post 210 and the magnetic reluctance between the magnetic sheet 50 and the first magnetic core 10. Similarly, the magnetic reluctance of the magnetic circuit corresponding to the second surface of the magnetic sheet 50 is the sum of the magnetic reluctance between the second surface of the magnetic sheet 50 and the first magnetic post 210 and the magnetic reluctance between the magnetic sheet 50 and the first magnetic core 10. Therefore, the magnitude of the magnetic reluctance R3 between the magnetic sheet 50 and the first magnetic core 10 does not affect the effect of the magnetic sheet 50 in directionally guiding and dispersing magnetic flux.

[0050] In other words, the distance between the magnetic sheet 50 and the first magnetic core 10 does not affect the directional guidance of the magnetic sheet 50 for the diffuse magnetic flux.

[0051] like Figure 3 As shown, the distance between the magnetic sheet 50 and the first magnetic core 10 can be equal to the distance between the first magnetic post 210 and the first magnetic core 10, that is, the side of the magnetic sheet 50 facing the first magnetic core 10 is flush with the side of the first magnetic post 210 facing the first magnetic core 10. Figure 6As shown, the distance between the magnetic sheet 50 and the first magnetic core 10 can be smaller than the distance between the first magnetic post 210 and the first magnetic core 10. For example... Figure 7 As shown, the distance between the magnetic sheet 50 and the first magnetic core 10 can be greater than the distance between the first magnetic post 210 and the first magnetic core 10.

[0052] In some embodiments, such as Figure 3 As shown, the distance between the magnetic sheet 50 and the first magnetic post 210 along the second direction Y is d1, and the distance between the side of the magnetic sheet 50 facing the coil 40 and the first magnetic post 210 is d2, satisfying: d2>1.5d1.

[0053] In this embodiment, the magnetic sheet 50 has a first surface facing the first magnetic post 210 and a second surface facing the coil 40, and the distance d1 between the magnetic sheet 50 and the first magnetic post 210 along the second direction Y is the vertical distance from the first surface of the magnetic sheet 50 to the first magnetic post 210.

[0054] The distance d1 between the first surface of the magnetic sheet 50 and the first magnetic post 210 along the second direction Y is less than the distance d2 between the second surface of the magnetic sheet 50 and the first magnetic post 210. Under the same size of the magnetic sheet 50, the magnetic resistance of the magnetic circuit corresponding to the first surface of the magnetic sheet 50 is less than the magnetic resistance of the magnetic circuit corresponding to the second surface of the magnetic sheet 50, thereby realizing the directional guidance of the magnetic sheet 50 on the diffuse magnetic flux.

[0055] With the same size magnetic sheet 50, the greater the difference between the distance between the first surface of the magnetic sheet 50 and the first magnetic post 210 and the distance between the second surface of the magnetic sheet 50 and the first magnetic post 210, the greater the difference between the magnetic resistance of the magnetic circuit corresponding to the first surface of the magnetic sheet 50 and the magnetic resistance of the magnetic circuit corresponding to the second surface of the magnetic sheet 50, and the stronger the effect of the magnetic sheet 50 in directionally guiding the dispersing magnetic flux.

[0056] In some embodiments, such as Figure 3 As shown, b is the width of the side of the magnetic sheet 50 facing the coil 40 along the second direction Y, which satisfies: .

[0057] In this embodiment, the thickness of the cross-section of the magnetic sheet 50 is defined as 'a', and the thickness of the cross-section of the magnetic sheet 50 is defined as 'b'. That is, the length of the first surface of the magnetic sheet 50 along the first direction Z is the thickness of the cross-section of the magnetic sheet 50, and the length of the second surface of the magnetic sheet 50 along the second direction Y is the thickness of the cross-section of the magnetic sheet 50. The distance between the magnetic sheet 50 and the first magnetic post 210 along the second direction Y is 'd1', and the distance between the side of the magnetic sheet 50 facing the coil 40 and the first magnetic post 210 is 'd2'.

[0058] Wherein, the distance d1 between the magnetic sheet 50 and the first magnetic post 210 along the second direction Y is the length of the magnetic circuit corresponding to the first surface of the magnetic sheet 50, and the distance d2 between the side of the magnetic sheet 50 facing the coil 40 and the first magnetic post 210 is the length of the magnetic circuit corresponding to the second surface of the magnetic sheet 50, satisfying: .

[0059] In some embodiments, such as Figure 2 and Figure 3 As shown, lg is the length of the air gap 30 along the first direction Z, μ0 is the free permeability, and Aec is the surface area of ​​the side of the first magnetic column 210 facing the air gap 30, satisfying: .

[0060] In this embodiment, the length lg of the air gap 30 along the first direction Z is the distance along the first direction Z between the end face of the first magnetic post 210 facing the first magnetic core 10 and the surface of the first magnetic core 10 facing the first magnetic post 210. The vacuum permeability μ0 is a physical constant with a value of approximately 4π × 10⁻⁶. -7 H / m. The surface area Aec of the side of the first magnetic column 210 facing the air gap 30 is the effective flow area when the magnetic flux passes through the air gap 30.

[0061] The above formula is based on Ohm's law for magnetic circuits. Magnetic reluctance is the ability of a magnetic circuit to impede the flow of magnetic flux. The greater the magnetic reluctance, the smaller the magnetic flux generated under the same magnetomotive force.

[0062] The air gap 30 is filled with air. The relative permeability of air is approximately 1. Therefore, the absolute permeability of the air gap 30 is the vacuum permeability. This parameter is a fixed constant and does not need to be measured.

[0063] It is understandable that the greater the ratio of the length lg of the air gap 30 along the first direction Z to the surface area Aec of the side of the first magnetic post 210 facing the air gap 30, the greater the magnetic reluctance of the air gap 30.

[0064] In some embodiments, such as Figure 2 and Figure 3 As shown, d1 is the distance between the magnetic sheet 50 and the first magnetic post 210 along the second direction Y, μ0 is the free permeability, and Aecp1 is the surface area of ​​the side of the magnetic sheet 50 facing the first magnetic post 210, satisfying: .

[0065] In this embodiment, the distance d1 between the magnetic sheet 50 and the first magnetic post 210 along the second direction Y is the spacing along the second direction Y between the end face of the first magnetic post 210 facing the magnetic sheet 50 and the surface of the magnetic sheet 50 facing the first magnetic post 210. The vacuum permeability μ0 is a physical constant with a value of approximately 4π × 10⁻⁶. -7H / m. The surface area Aecp1 of the side of the magnetic sheet 50 facing the first magnetic post 210 is the effective flow area when the magnetic flux passes through the magnetic circuit where the magnetic sheet 50 is located.

[0066] The above formula is based on Ohm's law for magnetic circuits. Magnetic reluctance is the ability of a magnetic circuit to impede the flow of magnetic flux. The greater the magnetic reluctance, the smaller the magnetic flux generated under the same magnetomotive force.

[0067] The air gap 30 is filled with air. The relative permeability of air is approximately 1. Therefore, the absolute permeability of the air gap 30 is the vacuum permeability. This parameter is a fixed constant and does not need to be measured.

[0068] It is understandable that the greater the ratio of the distance d1 between the magnetic sheet 50 and the first magnetic post 210 along the second direction Y to the surface area Aecp1 of the side of the magnetic sheet 50 facing the first magnetic post 210, the greater the magnetic resistance of the magnetic circuit corresponding to the first surface of the magnetic sheet 50.

[0069] In some embodiments, such as Figure 2 and Figure 3 As shown, d2 is the distance along the second direction Y between the side of the magnetic sheet 50 facing the coil 40 and the first magnetic post 210, μ0 is the free permeability, and Aecp2 is the surface area of ​​the side of the magnetic sheet 50 facing the coil 40, satisfying: .

[0070] In this embodiment, the distance d2 along the second direction Y between the side of the magnetic sheet 50 facing the coil 40 and the first magnetic post 210 is the spacing along the second direction Y between the end face of the first magnetic post 210 facing the coil 40 and the surface of the magnetic sheet 50 facing the coil 40. The vacuum permeability μ0 is a physical constant with a value of approximately 4π × 10⁻⁶. -7 H / m. The surface area Aecp2 of the side of the magnetic sheet 50 facing the coil 40 is the effective flow area when the magnetic flux passes through the magnetic circuit where the coil 40 is located.

[0071] The above formula is based on Ohm's law for magnetic circuits. Magnetic reluctance is the ability of a magnetic circuit to impede the flow of magnetic flux. The greater the magnetic reluctance, the smaller the magnetic flux generated under the same magnetomotive force.

[0072] The air gap 30 is filled with air. The relative permeability of air is approximately 1. Therefore, the absolute permeability of the air gap 30 is the vacuum permeability. This parameter is a fixed constant and does not need to be measured.

[0073] It is understandable that the greater the ratio of the distance d2 between the side of the magnetic sheet 50 facing the coil 40 and the first magnetic post 210 along the second direction Y to the surface area Aecp2 of the side of the coil 40 facing the first magnetic post 210, the greater the magnetic resistance of the magnetic circuit corresponding to the second side of the magnetic sheet 50.

[0074] In some embodiments, such as Figure 4As shown, magnetic sheet 50 is sheet-shaped.

[0075] In this embodiment, "sheet-like" means that the magnetic sheet 50 is generally a thin sheet shape in which the thickness along the first direction Z is much smaller than the length along the third direction X and the width along the second direction Y.

[0076] Understandably, the sheet structure facilitates arrangement in limited space. The height of the planar inductor 1 is usually quite limited, especially in applications requiring thinning and miniaturization. The sheet structure can be easily inserted into the narrow gap between the coil 40 and the first magnetic core 10 without significantly adjusting the overall height of the inductor 1. This allows the present application to achieve the additional function of dissipating magnetic flux without substantially changing the original structural dimensions of the inductor 1. At the same time, the sheet structure allows the magnetic sheet 50 to distribute more volume in the length and width directions, thereby obtaining the largest possible surface area within the limited height space to efficiently intercept the dissipating magnetic flux escaping from the air gap 30.

[0077] In addition, the magnetic sheet 50 has a variety of installation methods, including but not limited to being directly bonded to the surface of the insulation layer of the coil 40 by adhesive, being embedded in the insulation layer of the coil 40, or being installed on the surface of the insulation layer of the coil 40 by an independent insulating bracket or fastener.

[0078] In some embodiments, such as Figure 5 As shown, the magnetic sheet 50 includes multiple segments, and at least a portion of the magnetic sheet 50 is located on the side of the coil 40 facing the first magnetic post 210.

[0079] In this embodiment, the magnetic sheet 50 includes multiple segments, at least one of which is located between the first magnetic post 210 and the coil 40 along the second direction Y, that is, the projection of the magnetic sheet 50 along the second direction Y at least partially overlaps with the projection of the coil 40 along the second direction Y.

[0080] like Figure 5 As shown, the magnetic sheet 50 includes, but is not limited to, an L-shaped structure.

[0081] It is understandable that the L-shaped structure can increase the surface area of ​​the side of the magnetic sheet 50 facing the first magnetic post 210, thereby reducing the magnetic resistance of the magnetic circuit corresponding to the first side of the magnetic sheet 50.

[0082] In some embodiments, such as Figure 1 As shown, the length of the magnetic sheet 50 along the third direction X is the same as the length of the first magnetic post 210 along the third direction X.

[0083] In this embodiment, the length of the air gap 30 along the third direction X is the same as the length of the first magnetic column 210 along the third direction X, and the magnetic sheet 50 is located between the air gap 30 and the coil 40, so as to achieve full coverage interception of the diffuse magnetic flux of the air gap 30.

[0084] In other words, the air gap 30 extends along the third direction X, and the magnetic flux at the air gap 30 mainly diffuses along the second direction Y towards the coil 40. The magnetic sheet 50 can completely cover the air gap 30 in the third direction X, so that the magnetic flux escaping from the air gap 30 can be intercepted by the magnetic sheet 50 at various positions in the third direction X.

[0085] In some embodiments, such as Figure 4 and Figure 5 As shown, the projection of the magnetic sheet 50 along the first direction Z at least partially coincides with the projection of the coil 40 along the first direction Z.

[0086] In this embodiment, the diffusion range of the scattered magnetic flux at the air gap 30 without the magnetic plate 50 will affect the portion of the coil 40 near the air gap 30. The magnetic plate 50 is mounted on the side of the coil 40 facing the first magnetic core 10, and the magnetic plate 50 at least covers the original influence range of the scattered magnetic flux at the air gap 30 on the coil 40. In other words, a portion of the magnetic plate 50 is located on the side of the coil 40 facing the first magnetic core 10, and another portion of the magnetic plate 50 protrudes from the side of the coil 40 facing the first magnetic post 210.

[0087] This application also provides an electrical device. The electrical device includes the inductor 1 described above.

[0088] In this embodiment, the electrical equipment can be a power conversion device such as an inverter, an energy storage converter, or a charging pile, or an electrical device such as a distribution cabinet.

[0089] Electrical equipment typically includes cabinets, heat sinks, energy storage components, and heat-conducting components. A cabinet is the outer shell structure within electrical equipment used to house energy storage components. It encloses and forms a cavity to house these components, protecting the internal parts of the electrical equipment. Cabinets provide physical isolation and protection for the internal energy storage components. Energy storage components include, but are not limited to, capacitors or inductors.

[0090] According to the electrical equipment provided in the embodiments of this application, by using the inductor 1 described above, the scattered magnetic flux passing through the coil 40 can be reduced, thereby reducing the loss of the coil 40.

[0091] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0092] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0093] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0094] In the description of this application, "multiple" means two or more.

[0095] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0096] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0097] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0098] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. An inductor (1), characterized in that, include: First magnetic core (10); The second magnetic core (20) includes a magnetic core substrate (230), a first magnetic post (210), and a second magnetic post (220). The magnetic core substrate (230) and the first magnetic core (10) are spaced apart along a first direction. The first magnetic post (210) and the second magnetic post (220) are spaced apart along a second direction. An accommodating space is formed between the first magnetic post (210), the second magnetic post (220), and the magnetic core substrate (230). The second magnetic post (220) and the first magnetic core (10) are connected. An air gap (30) is formed between the first magnetic post (210) and the first magnetic core (10). A coil (40) is installed in the accommodating space and wound around the second magnetic post (220); A magnetic sheet (50) is disposed between the first magnetic post (210) and the second magnetic post (220). The distance between the magnetic sheet (50) and the first magnetic post (210) is less than the distance between the magnetic sheet (50) and the second magnetic post (220). The distance between the magnetic sheet (50) and the first magnetic post (210) is less than the distance between the coil (40) and the first magnetic post (210). The distance between the magnetic sheet (50) and the first magnetic core (10) is less than the distance between the coil (40) and the first magnetic core (10).

2. The inductor (1) according to claim 1, characterized in that, The magnetic resistance of the air gap (30) is Rg, the magnetic resistance between the side of the magnetic sheet (50) facing the first magnetic post (210) and the first magnetic post (210) is R1, and the magnetic resistance between the side of the magnetic sheet (50) facing the coil (40) and the first magnetic post (210) is R2, satisfying: Rg < R1 < R2.

3. The inductor (1) according to claim 1, characterized in that, The distance between the magnetic sheet (50) and the first magnetic post (210) along the second direction is d1, and the distance between the side of the magnetic sheet (50) facing the coil (40) and the first magnetic post (210) is d2, satisfying: d2 > 1.5d1.

4. The inductor (1) according to claim 3, characterized in that, ； Wherein, b is the width of the side of the magnetic sheet (50) facing the coil (40) along the second direction.

5. The inductor (1) according to claim 1, characterized in that, The magnetic sheet (50) comprises multiple segments, at least a portion of which is located on the side of the coil (40) facing the first magnetic post (210).

6. The inductor (1) according to claim 1, characterized in that, The length of the magnetic sheet (50) along the third direction is the same as the length of the first magnetic column (210) along the third direction, and the first direction, the second direction and the third direction intersect each other.

7. The inductor (1) according to claim 1, characterized in that, The projection of the magnetic sheet (50) along the first direction at least partially overlaps with the projection of the coil (40) along the first direction.

8. The inductor (1) according to any one of claims 1-7, characterized in that, ； Wherein, R1 is the magnetic resistance between the side of the magnetic sheet (50) facing the first magnetic post (210) and the first magnetic post (210), d1 is the distance between the magnetic sheet (50) and the first magnetic post (210) along the second direction, μ0 is the vacuum permeability, and Aecp1 is the surface area of ​​the side of the magnetic sheet (50) facing the first magnetic post (210).

9. The inductor (1) according to any one of claims 1-7, characterized in that, ； Wherein, R2 is the magnetic resistance between the side of the magnetic sheet (50) facing the coil (40) and the first magnetic post (210), d2 is the distance between the side of the magnetic sheet (50) facing the coil (40) and the first magnetic post (210), μ0 is the vacuum permeability, and Aecp2 is the surface area of ​​the side of the magnetic sheet (50) facing the coil (40).

10. An electrical device, characterized in that, include: The inductor (1) as described in any one of claims 1-9.

Images