Magnetic core and preparation method thereof, transformer and preparation method thereof, and electronic equipment

Abstract

The present application provides a magnetic core and a preparation method thereof, a transformer and a preparation method thereof, and an electronic device; the magnetic core comprises a magnetic core body; wherein an air gap is arranged on the side wall of the magnetic core body, and the air gap spirally extends from the first end of the magnetic core body to the second end along the length direction of the magnetic core body; and the depth of the air gap is less than the radius of the magnetic core body. The magnetic core effectively reduces the magnetic impedance, thereby improving the anti-saturation ability of the magnetic core, and effectively reduces the loss, so that the transformer has a low loss characteristic under high-frequency working state, and is conducive to miniaturization design.

Description

Technical Field

[0001] The present invention relates to the field of electronic technology, and in particular to a magnetic core and a preparation method thereof, a transformer and a preparation method thereof, and electronic equipment. Background Art

[0002] With the continuous development of electronic technology and space utilization, transformers tend to be miniaturized and highly integrated to meet the needs of modern equipment and systems.

[0003] However, the miniaturization and integration of transformers have higher requirements for the internal magnetic core and structural design. The structural design is more compact, making it difficult to achieve effective heat dissipation. When the heat dissipation deteriorates, the temperature of the transformer will increase, which will affect the performance of the transformer and reduce its conversion efficiency at high frequencies. At the same time, the loss of the transformer is proportional to the operating frequency. The higher the frequency, the higher the copper loss of the conductor and the magnetic core loss generated by the transformer. However, it is difficult for existing transformers to meet the performance requirements of low loss at high frequencies. Summary of the invention

[0004] The magnetic core and its preparation method, transformer and its preparation method, and electronic equipment provided in the present application are intended to solve the problem that existing transformers cannot achieve low-loss and miniaturized design under high-frequency conditions.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is to provide a magnetic core, comprising:

[0006] A magnetic core body, wherein an air gap is arranged on the side wall of the magnetic core body, and the air gap spirally extends from the first end of the magnetic core body to the second end along the length direction of the magnetic core body; and the depth of the air gap is smaller than the radius of the magnetic core body.

[0007] In a specific embodiment, the depth of the air gap is 10%-30% of the radius of the magnetic core body.

[0008] In a specific embodiment, the depth of the air gap is 15%-25% of the radius of the magnetic core body.

[0009] In a specific embodiment, the width of the air gap is 0.1 mm-0.5 mm.

[0010] In a specific embodiment, the width of the air gap is 0.2 mm-0.4 mm.

[0011] In a specific embodiment, the distance between two adjacent turns of the air gap is 3 mm-5 mm.

[0012] In a specific embodiment, the distance between two adjacent turns of the air gap is 3.5 mm-4.5 mm.

[0013] In a specific embodiment, it also includes:

[0014] A first heat dissipation layer and / or a second heat dissipation layer, wherein the first heat dissipation layer is arranged on a partial circumferential surface of the magnetic core body close to the first end and / or the first end face; and the second heat dissipation layer is arranged on a partial circumferential surface of the magnetic core body close to the second end and / or the second end face.

[0015] In a specific embodiment, the material of the first heat dissipation layer includes a first magnetic material, and / or,

[0016] The material of the second heat dissipation layer includes a second magnetic material.

[0017] In a specific embodiment, the first magnetized material includes at least one of magnetized aluminum oxide, boron oxide or aluminum nitride; or

[0018] The second magnetized material includes at least one of magnetized aluminum oxide, boron oxide, or aluminum nitride.

[0019] In a specific embodiment, the material of the magnetic core body includes a composite magnetic material, and the composite magnetic material includes:

[0020] 3-4 parts by weight of nickel-zinc alloy, 3-4 parts by weight of magnesium-zinc alloy, 13-16 parts by weight of iron oxide, and 12-15 parts by weight of iron.

[0021] In a specific embodiment, the nickel-zinc alloy comprises a material having a structural formula of NiyZn, wherein y is 1-2; and / or,

[0022] The magnesium-zinc alloy includes a material with a structural formula of MgZnz, wherein z is 0.5-1.

[0023] In a specific embodiment, the composite magnetic material includes any one or more of manganese-zinc alloy, nickel-iron alloy, and iron-manganese alloy, wherein the mass fraction of the manganese-zinc alloy is 2-4 parts, the mass fraction of the nickel-iron alloy is 3-4 parts, and the mass fraction of the iron-manganese alloy is 2-4 parts.

[0024] In a specific embodiment, the composite magnetic material further includes 0.5-1.5 parts by mass of a silicon-containing substance, wherein the silicon-containing substance includes elemental silicon and / or silicon oxide.

[0025] In a specific embodiment, the microstructure of the composite magnetic material includes:

[0026] The multi-layered magnetic material layer is nested in sequence from the center along the radial direction outwards.

[0027] In a specific embodiment, the multi-layered magnetic material layer comprises:

[0028] A first magnetic material layer, wherein the first magnetic material layer comprises a manganese-zinc alloy;

[0029] A second magnetic material layer, arranged outside the first magnetic material layer, wherein the second magnetic material layer comprises a nickel-zinc alloy and / or a manganese-zinc alloy;

[0030] The third magnetic material layer is arranged outside the second magnetic material layer in an annular manner, and the third magnetic material layer includes a nickel-iron alloy.

[0031] In a specific embodiment, the magnetic core body comprises a composite magnetic material, and the raw materials of the composite magnetic material include:

[0032] A first raw material, the first raw material comprising 1-2 parts by weight of iron, 0.5-1.5 parts by weight of nickel, 0.5-1.5 parts by weight of zinc, and 0.5-1.5 parts by weight of silicon;

[0033] The second raw material comprises 0.8-1.2 parts by weight of nickel oxide and 0.8-1.2 parts by weight of magnesium oxide.

[0034] In a specific embodiment, the first raw material includes 0.5-1.5 parts by weight of manganese and / or 0.5-1.5 parts by weight of magnesium;

[0035] The second raw material includes one or more of manganous manganate, ferric oxide and zinc oxide, wherein the mass fraction of the manganous manganate is 1 part to 1.5 parts, the mass fraction of the ferric oxide is 0.3 parts to 0.8 parts, and the mass fraction of the zinc oxide is 1 part to 1.5 parts.

[0036] In a specific embodiment, the mass ratio of the first raw material to the second raw material is 2.3:1-1.3:1.

[0037] In order to solve the above technical problems, another technical solution adopted by the present application is: to provide a method for preparing a magnetic core, which is used to prepare the magnetic core involved in any one of the above items, comprising:

[0038] Providing a magnetic core substrate;

[0039] The side wall of the magnetic core substrate is cut to form an air gap to obtain the magnetic core body; the air gap spirally extends from the first end of the magnetic core body to the second end along the length direction of the magnetic core body; and the depth of the air gap is less than the radius of the magnetic core body.

[0040] In a specific embodiment, providing a magnetic core matrix includes:

[0041] Providing a composite magnetic material; the composite magnetic material is the composite magnetic material involved in any one of the above items;

[0042] The composite magnetic material is die-cast to form a magnetic core matrix.

[0043] In a specific embodiment, the step of providing the composite magnetic material specifically includes:

[0044] Providing a first raw material and a second raw material; wherein the first raw material includes a plurality of single substances, and the single substances specifically include the plurality of metal single substances and silicon; and the second raw material includes a plurality of oxides;

[0045] Respectively mixing each of the metal elements and at least one of the oxides other than the oxide of the element and heating them to obtain a plurality of material components;

[0046] Cooling and solidifying the multiple material components;

[0047] Using a pulverizer to pulverize the plurality of material components to obtain particles of the plurality of material components;

[0048] The plurality of material component particles are magnetized and mixed to obtain the composite magnetic material.

[0049] In a specific embodiment, the step of providing the composite magnetic material specifically includes:

[0050] Providing a first raw material and a second raw material; wherein the first raw material includes a plurality of single substances, and the single substances specifically include the plurality of metal single substances and silicon; and the second raw material includes a plurality of oxides;

[0051] The first raw material and the second raw material are mixed and heated to obtain an initial product;

[0052] Cooling and solidifying the initial product;

[0053] Using a pulverizer to pulverize the solidified initial product to obtain mixed product particles;

[0054] The mixed product particles are magnetized and mixed to prepare a composite magnetic material.

[0055] In a specific embodiment, it also includes:

[0056] Depositing a first magnetized material on a partial circumferential surface and / or an end surface of the magnetic core body close to the first end to form a first heat dissipation layer; and / or,

[0057] A second magnetized material is deposited on a portion of the circumferential surface and / or the end surface of the magnetic core body close to the second end to form a second heat dissipation layer.

[0058] In order to solve the above technical problems, another technical solution adopted by the present application is: to provide a transformer, comprising:

[0059] A magnetic core, which is any of the magnetic cores mentioned above;

[0060] A winding group is arranged on the surface of the magnetic core between two adjacent turns of the air gap; the winding group includes a plurality of windings;

[0061] The equipment frame is covered outside the magnetic core and the winding group.

[0062] In a specific embodiment, it also includes:

[0063] A first magnet and a second magnet; the magnetic core is disposed between the first magnet and the second magnet;

[0064] The magnetic conductive portion is arranged on the side surface of the magnetic core close to the first magnet and / or the second magnet; the magnetic conductive portion is annular, the inner side surface of the magnetic conductive portion is arranged close to the side wall of the magnetic core, and the outer side surface of the magnetic conductive portion is an inclined surface; and the width of the magnetic conductive portion gradually decreases along the direction from the first magnet and / or the second magnet toward the magnetic core.

[0065] In a specific embodiment, along the length direction of the magnetic core, the height of the magnetic conductive portion is 1%-15% of the height of the magnetic core.

[0066] In a specific embodiment, along the length direction of the magnetic core, the height of the magnetic conductive portion is 5%-10% of the height of the magnetic core.

[0067] In a specific embodiment, the angle between the inclined surface and the side surface of the magnetic core is 30°-60°.

[0068] In a specific embodiment, the angle between the inclined surface and the side surface of the magnetic core is 40°-50°.

[0069] In a specific embodiment, the inclined surface is a plane or a curved surface.

[0070] In order to solve the above technical problems, another technical solution adopted by the present application is: to provide a method for preparing a transformer, comprising:

[0071] Providing a magnetic core; the magnetic core is the magnetic core involved in any one of the above items;

[0072] Winding a plurality of windings on the surface between two adjacent turns of the air gap of the magnetic core to form a winding group;

[0073] An equipment skeleton is arranged outside the magnetic core and the winding group.

[0074] In a specific embodiment, after the step of providing the magnetic core, the method further includes:

[0075] A first magnet and a second magnet are respectively formed at two ends of the magnetic core along the length direction of the magnetic core, so that the magnetic core is located between the first magnet and the second magnet;

[0076] Magnetic material is deposited on the side surface of the magnetic core close to the first magnet and / or the second magnet to form a magnetic conductive portion; the magnetic conductive portion is annular, the inner side surface of the magnetic conductive portion is arranged in close contact with the side wall of the magnetic core, and the outer side surface of the magnetic conductive portion is an inclined surface; and along the direction from the first magnet and / or the second magnet toward the magnetic core, the width of the magnetic conductive portion gradually decreases.

[0077] In order to solve the above technical problems, another technical solution adopted in the present application is: to provide an electronic device, including a circuit board and a transformer involved in any one of the above items, wherein the transformer is arranged on the circuit board.

[0078] Beneficial effects of the embodiments of the present application: Different from the prior art, the present application provides a magnetic core and a preparation method thereof, a transformer and a preparation method thereof, and an electronic device; the magnetic core includes a magnetic core body, an air gap is provided on the side wall of the magnetic core body, and the air gap spirally extends from the first end of the magnetic core body to the second end along the length direction of the magnetic core body; and the depth of the air gap is less than the radius of the magnetic core body. By providing a spiral air gap on the side wall of the magnetic core body and making the depth of the air gap less than the radius of the magnetic core body, so that the magnetic core will not be completely cut off by the air gap, the magnetic impedance of the magnetic core is effectively reduced, thereby improving the anti-saturation ability of the magnetic core, and effectively reducing the loss, so that the transformer has a low loss characteristic under high-frequency working conditions, which is conducive to the miniaturization design of the transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 A schematic diagram of the structure of a transformer provided in one embodiment of the present application;

[0080] Figure 2 for Figure 1 The transformer is shown in a cross-sectional view along line AA;

[0081] Figure 3a for Figure 2 A partial enlarged view of the structure shown at point A;

[0082] Figure 3b for Figure 2 A partial enlarged view of position B in the structure shown;

[0083] Figure 3cA partial enlarged view of point A in a transformer provided by another embodiment of the present application;

[0084] Figure 3d A partial enlarged view of a transformer at point B provided in another embodiment of the present application;

[0085] Figure 4a A partial enlarged view of point A in a transformer provided in one embodiment of the present application;

[0086] Figure 4b A cross-sectional view of a magnetic core in a transformer provided by another embodiment of the present application along line BB;

[0087] Figure 4c A partial enlarged view of point A in a transformer provided in yet another embodiment of the present application;

[0088] Figure 4d A partial enlarged view of a transformer at point A provided in another embodiment of the present application;

[0089] Figure 5a A cross-sectional view of a transformer along line AA provided by another embodiment of the present application;

[0090] Figure 5b A cross-sectional view of a transformer along line AA provided in yet another embodiment of the present application;

[0091] Figure 6 A schematic diagram of a process for preparing a magnetic core provided in one embodiment of the present application;

[0092] Figure 7 for Figure 6 Schematic diagram of the process of step S11;

[0093] Figure 8a for Figure 7 Schematic diagram of the process of step S111;

[0094] Figure 8b for Figure 7 A flowchart of another implementation of step S111;

[0095] Fig. 9 A schematic diagram of a process for preparing a transformer provided in an embodiment of the present application;

[0096] Fig.10 for Figure 1 The saturation magnetic induction intensity curve of the magnetic core in the transformer shown at different temperatures;

[0097] Fig.11 for Figure 1 The power loss curve of the magnetic core in the transformer shown at different temperatures;

[0098] Fig.12 A microstructure diagram of the composite magnetic material of the magnetic core body in the transformer provided in Example 9 of the present application:

[0099] Fig.13 This is a cross-sectional view of the transformer provided for comparative example 1 along line AA.

[0100] Description of Figure Numbers:

[0101] 1-magnetic core; 2-winding group; 3-equipment skeleton; 4-first magnet; 5-second magnet; 6-magnetic conductive part; 10-magnetic material layer; 11-magnetic core body; 12-air gap; 13-first heat dissipation layer; 14-second heat dissipation layer; 101-first magnetic material layer; 102-second magnetic material layer; 103-third magnetic material layer; 111-first end; 112-second end; 131-first sub-heat dissipation layer; 132-second sub-heat dissipation layer. DETAILED DESCRIPTION

[0102] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0103] The terms "first", "second" and "third" in this application are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second" and "third" can explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications (such as up, down, left, right, front, back...) in the embodiments of this application are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0104] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0105] The present application is described in detail below with reference to the accompanying drawings and embodiments.

[0106] See also Figure 1-Figure 3b , Figure 1 A schematic diagram of the structure of a transformer provided in one embodiment of the present application; Figure 2 for Figure 1 The transformer is shown in a cross-sectional view along line AA; Figure 3a for Figure 2 A partial enlarged view of the structure shown at point A; Figure 3b for Figure 2 A partial enlarged view of the structure shown at B. In a first aspect, the present application provides a transformer, which can be used in electronic equipment to transmit electrical energy between two or more coils through electromagnetic coupling and can change the magnitude of AC voltage and current. The transformer can include a magnetic core 1, a winding group 2 and a device frame 3.

[0107] Among them, the magnetic core 1 may include a magnetic core body 11, and an air gap 12 is arranged on the side wall of the magnetic core body 11. The air gap 12 refers to the gap left in the magnetic core body 11, and can be formed on the magnetic core body 11 by cutting. Those skilled in the art can understand that the air gap 12 in the magnetic core body 11 can change the magnetic permeability of the magnetic core 1, thereby affecting the distribution of the magnetic field and the performance of the magnetic core 1. Specifically, the air gap 12 reduces the overall magnetic permeability of the magnetic core 1, making the magnetic core 1 easier to be magnetized, effectively reducing the magnetic impedance; it can also increase the saturation magnetic induction intensity of the magnetic core 1; reduce magnetic loss, and thus improve the efficiency of the transformer.

[0108] The traditional air gap 12 structure usually completely cuts off the core body 11 along the cross section to form multiple independent structures; when the air gap 12 is very small, although its magnetic permeability is still lower than the case without the air gap 12, the magnetic impedance of the core 1 will actually increase due to the existence of the air gap 12. This is because the air gap 12 introduces a new source of magnetic impedance. Even if the magnetic permeability is reduced, the air gap 12 itself acts as a physical barrier to hinder the flow of the magnetic field. In this case, the air gap 12 plays a role similar to an inductor and increases the magnetic impedance. This effect is more obvious in high-frequency applications because high-frequency magnetic fields are more easily affected by the air gap 12.

[0109] like Figure 1As shown, in the embodiment of the present application, the air gap 12 spirally extends from the first end 111 of the magnetic core body 11 to the second end 112 along the length direction X of the magnetic core body 11, so as to form a spiral air gap 12 structure on the magnetic core body 11; and the depth of the air gap 12 is less than the radius of the magnetic core body 11, so that the magnetic core body 11 can maintain its overall continuous structure. Specifically, each turn of the spiral air gap 12 is arranged at intervals. Among them, the first end 111 and the second end 112 of the magnetic core body 11 are opposite ends of the magnetic core body 11 along the length direction X.

[0110] The winding group 2 is arranged on the surface of the magnetic core 1 between two adjacent turns of the air gap 12, and spirally surrounds the magnetic core 1. One end of the winding group 2 is an input end, and the other end is an output end, which is used to transmit energy and signals; according to the electromagnetic induction effect, when current passes through the winding group 2, the magnetic core 1 will generate a magnetic field. Specifically, the winding group 2 includes a plurality of windings.

[0111] The equipment skeleton 3 is arranged on the outside of the magnetic core 1 and the winding group 2 to provide mechanical support for the winding group 2 so that the winding group 2 can be stably placed on the magnetic core 1 to prevent the winding group 2 from loosening or being damaged when subjected to vibration and impact; it can also provide good electrical isolation to prevent short circuits or grounding faults between the winding groups 2; in addition, the equipment skeleton 3 can also help dissipate heat and improve the heat dissipation effect of the transformer.

[0112] In this way, by setting a spiral air gap 12 on the side wall of the core body 11 and making the depth of the air gap 12 smaller than the radius of the core body 11, so that the core body 11 will not be completely cut off by the air gap 12, the magnetic impedance of the core 1 is effectively reduced, thereby improving the anti-saturation ability of the core 1 and effectively reducing the loss, so that the transformer has a low loss characteristic under high-frequency working conditions.

[0113] Those skilled in the art will appreciate that the depth a of the air gap 12 will affect the magnetic permeability and magnetic impedance of the magnetic core 1, thereby affecting the efficiency, output voltage and current of the transformer. Figure 2 As shown, in a specific embodiment, the depth a of the air gap 12 can be 10%-30% of the radius of the magnetic core body 11, so as to improve the anti-saturation ability of the magnetic core 1 while reducing the magnetic impedance. Wherein, along the radial direction Y of the magnetic core body 11, the air gap 12 extends from the side wall surface of the magnetic core body 11 toward the axis of the magnetic core body 11 to form a groove structure; the depth of the air gap 12 is the depth of the groove structure, that is, the distance between the bottom wall of the groove structure and the side wall surface of the magnetic core 1. Specifically, the depth a of the air gap 12 can be any value of 10%, 15%, 20%, 25% or 30% of the radius of the magnetic core body 11; or a range value composed of any two of the above values, for example, 10%-20%, 15%-25%, 20%-30%, etc.

[0114] Preferably, the depth of the air gap 12 is 15%-25% of the radius of the magnetic core 1, so that the magnetic impedance and anti-saturation ability of the magnetic core 1 can reach excellent levels; specifically, the depth a of the air gap 12 can be any value of 15%, 18%, 20%, 22% or 25% of the radius of the magnetic core body 11; or a range value composed of any two of the above values, for example, 15%-20%, 18%-22%, 20%-25%, etc.

[0115] Further, such as Figure 3a As shown, the width b of the air gap 12 is 0.1mm-0.5mm, so as to further reduce the magnetic impedance and magnetic loss of the magnetic core 1 and improve the anti-saturation ability of the magnetic core 1. It can be understood that the larger the width b of the air gap 12, the larger the magnetic impedance of the magnetic core 1, the stronger the anti-saturation ability, and the lower the magnetic loss of the magnetic core 1; setting the width of the air gap 12 to 0.1mm-0.5mm can reduce the magnetic impedance of the magnetic core 1, improve the anti-saturation ability, and reduce the magnetic loss of the magnetic core 1, so as to achieve low loss of the transformer in a high-frequency state. Specifically, the width b of the air gap 12 can be any value of 0.1mm, 0.2mm, 0.25mm, 0.3mm, 0.4mm or 0.5mm; or a range value composed of any two of the above values, for example, 0.1mm-0.25mm, 0.2mm-0.3mm, 0.3mm-0.5mm, etc.

[0116] Preferably, the width b of the air gap 12 is 0.2 mm-0.4 mm; specifically, the width b of the air gap 12 can be any value of 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm or 0.4 mm; or a range of any two of the above values, for example, 0.2 mm-0.3 mm, 0.25 mm-0.35 mm, 0.3 mm-0.4 mm, etc. The width b of the air gap 12 at different positions is theoretically equal, but there may be errors in the actual production process, as long as the error does not exceed ±0.01 mm.

[0117] like Figure 2 As shown, in a specific embodiment, the distance d between two adjacent turns of the air gap 12 is 3mm-5mm, so that the interval between two adjacent turns of the air gap 12 can accommodate the winding group 2. It can be understood that the distance d between two adjacent turns is related to the diameter of the winding; preferably, the winding group 2 can specifically include 3-4 windings, and the distance d between two adjacent turns can be 4-5 times the diameter of the winding. Specifically, the distance d between two adjacent turns of the air gap 12 can be any value of 3mm, 3.5mm, 4mm, 4.5mm or 5mm; or a range value composed of any two of the above values, for example, 3mm-4mm, 3.5mm-4.5mm, 4mm-5mm, etc.

[0118] Preferably, the distance d between two adjacent turns of the air gap 12 is 3.5mm-4.5mm; specifically, the distance d between two adjacent turns of the air gap 12 can be any value of 3.5mm, 3.8mm, 4mm, 4.2mm or 4.5mm; or a range value composed of any two of the above values, for example, 3.5mm-4mm, 3.8mm-4.2mm, 4mm-4.5mm, etc.

[0119] In a specific embodiment, the distance d between two adjacent turns of different air gaps 12 is usually equal, so as to facilitate the manufacture of standard parts and ensure stable product performance. Of course, in some embodiments, the distance d between two adjacent turns of different air gaps 12 may also be unequal, as long as the difference in the distance d between two adjacent turns does not exceed ±0.25 mm.

[0120] Among them, combined Figure 2 , Figure 3a and Figure 3b , the magnetic core 1 may further include a first heat dissipation layer 13 and / or a second heat dissipation layer 14; wherein the first heat dissipation layer 13 is arranged on a portion of the circumferential surface of the magnetic core body 11 close to the first end 111, and the second heat dissipation layer 14 is arranged on a portion of the circumferential surface of the magnetic core body 11 close to the second end 112. The inventors have found in combination with engineering practice that the local temperature rise of the regions at both ends of the magnetic core body 11 is relatively high. By respectively arranging the first heat dissipation layer 13 and the second heat dissipation layer 14 on the circumferential outer surfaces close to both ends of the magnetic core 1, the heat dissipation performance of the magnetic core 1 can be improved, and the risk of a reduction in the conversion efficiency of the transformer at high frequencies due to an increase in temperature is reduced, thereby effectively improving the performance of the transformer and facilitating the miniaturization design of the transformer.

[0121] Specifically, Figure 3a and Figure 3b As shown, the first heat dissipation layer 13 can be arranged on the side surface of the magnetic core body 11 close to the first end 111, and the second heat dissipation layer 14 can be arranged on the side surface of the magnetic core body 11 close to the second end 112; and along the length direction X of the magnetic core body 11, the height h1 of the first heat dissipation layer 13 and the height h2 of the second heat dissipation layer 14 can be 1%-15% of the height of the magnetic core body 11, and cover the part of the side surface of the magnetic core 1 not covered by the winding group 2, so as to prevent the winding group 2 from being arranged on the first heat dissipation layer 13 and the second heat dissipation layer 14 as much as possible. It can be understood that if the winding group 2 is arranged on the first heat dissipation layer 13 and the second heat dissipation layer 14, the distance between the winding group 2 and the center of the magnetic core body 11 will increase, resulting in increased magnetic loss. Specifically, the height h1 of the first heat dissipation layer 13 and the height h2 of the second heat dissipation layer 14 can be any value of 1%, 5%, 10%, 12% or 15% of the height of the magnetic core 1; or a range value composed of any two of the above values, for example, 1%-10%, 5%-12%, 10%-15%, etc.

[0122] Preferably, the height h1 of the first heat dissipation layer 13 and the height h2 of the second heat dissipation layer 14 can be 5%-10% of the height of the magnetic core body 11; specifically, the height h1 of the first heat dissipation layer 13 and the height h2 of the second heat dissipation layer 14 can be any value of 5%, 7%, 8%, 9% or 10% of the height of the magnetic core body 11; or a range value composed of any two of the above values, for example, 5%-8%, 7%-9%, 8%-10%, etc.

[0123] See also Figure 3a-3d , Figure 3c A partial enlarged view of point A in a transformer provided by another embodiment of the present application; Figure 3d This is a partial enlarged view of B in a transformer provided by another embodiment of the present application. Figure 3a and Figure 3b As shown, in some embodiments, the height h1 of the first heat dissipation layer 13 and the height h2 of the second heat dissipation layer 14 may be the same.

[0124] like Figure 3c and Figure 3b As shown, in other embodiments, the height h1 of the first heat dissipation layer 13 and the height h2 of the second heat dissipation layer 14 may also be different; specifically, the height h1 of the first heat dissipation layer 13 may be greater than the height h2 of the second heat dissipation layer 14. Of course, in other embodiments, the height h1 of the first heat dissipation layer 13 may also be less than the height h2 of the second heat dissipation layer 14.

[0125] See also Figure 4a , Figure 4a A local enlarged view of point A in the transformer provided in an embodiment of the present application; in an embodiment of the present application, the first heat dissipation layer 13 may include multiple sub-heat dissipation layers. For ease of understanding, the present application embodiment is described by taking the first heat dissipation layer 13 including two sub-heat dissipation layers as an example. For ease of distinction, the two sub-heat dissipation layers are respectively a first sub-heat dissipation layer 131 and a second sub-heat dissipation layer 132. The first sub-heat dissipation layer 131 and the second sub-heat dissipation layer 132 are arranged at intervals, and the first sub-heat dissipation layer 131 and the second sub-heat dissipation layer 132 respectively surround the circumferential surface of the magnetic core body 11, the first sub-heat dissipation layer 131 is arranged on the side close to the first end 111, and the second sub-heat dissipation layer 132 is arranged on the side of the first sub-heat dissipation layer 131 away from the first end 111.

[0126] See also Figure 4b , Figure 4b A cross-sectional view of a magnetic core in a transformer provided in another embodiment of the present application along line BB; in another embodiment, the first sub-heat dissipation layer 131 and the second sub-heat dissipation layer 132 respectively surround half of the circumference of the magnetic core body 11, and the first sub-heat dissipation layer 131 and the second sub-heat dissipation layer 132 are combined into a circumference.

[0127] See also Figure 4c , Figure 4c A cross-sectional view of a magnetic core in a transformer provided in another embodiment of the present application along line BB; in yet another embodiment, the first sub-heat dissipation layer 131 and the second sub-heat dissipation layer 132 respectively surround a partial circumference of the magnetic core body 11, the first sub-heat dissipation layer 131 and the second sub-heat dissipation layer 132 are located on the same circumference, and there is a gap between the first sub-heat dissipation layer 131 and the second sub-heat dissipation layer 132.

[0128] See also Figure 4d , Figure 4d A local enlarged view of point A in the transformer provided in another embodiment of the present application; in another embodiment, the first sub-heat dissipation layer 131 and the second sub-heat dissipation layer 132 are stacked, the first sub-heat dissipation layer 131 is arranged on the outer peripheral surface of the magnetic core body 11, and the second sub-heat dissipation layer 132 is arranged on the surface of the first sub-heat dissipation layer 131 away from the magnetic core body 11.

[0129] The present application is not limited to the arrangement of the multiple sub-heat dissipation layers, and the materials of the multiple sub-heat dissipation layers may be the same, or different, or partially the same and partially different. The second heat dissipation layer 14 may also include multiple sub-heat dissipation layers, which are arranged on a portion of the circumferential surface near the second end 112, and the arrangement method thereof is similar to the arrangement method of the first heat dissipation layer 13, which will not be elaborated in detail here.

[0130] like Figure 5a As shown, Figure 5a A cross-sectional view of a transformer along line AA provided in another embodiment of the present application; in some embodiments, a first heat dissipation layer 13 may also be disposed on an end surface of a first end 111 of a magnetic core body 11, and a second heat dissipation layer 14 may also be disposed on an end surface of a second end 112 of the magnetic core body 11; so that the winding group 2 on the surface of the magnetic core body 11 does not need to avoid the first heat dissipation layer 13 and the second heat dissipation layer 14, thereby reducing the length of the magnetic core body 11 to reduce costs; and it may also prevent materials of the first heat dissipation layer 13 and the second heat dissipation layer 14 from entering the air gap, thereby causing increased losses in the magnetic core body 11.

[0131] like Figure 5b As shown, Figure 5b A cross-sectional view of the transformer along line AA is provided for another embodiment of the present application; in other embodiments, the first heat dissipation layer 13 and the second heat dissipation layer 14 can also be arranged on the outer surface of the device skeleton 3 of the transformer and completely cover the outer surface of the skeleton 3 to further improve the heat dissipation performance of the transformer.

[0132] Specifically, the material of the first heat dissipation layer 13 may include a first magnetic material, and the material of the second heat dissipation layer 14 may include a second magnetic material, so that the first heat dissipation layer 13 and the second heat dissipation layer 14 can be tightly combined with the magnetic core body 11. Specifically, the first magnetic material is deposited on the side surface of the magnetic core body 11 close to the first end 111 by coating or spraying to form the first heat dissipation layer 13; the second magnetic material is deposited on the side surface of the magnetic core body 11 close to the second end 112 by coating or spraying to form the second heat dissipation layer 14.

[0133] Among them, the first magnetized material may include at least one of aluminum oxide, boron oxide or aluminum nitride that has been magnetized, and the second magnetized material may also include at least one of aluminum oxide, boron oxide or aluminum nitride that has been magnetized. Specifically, if the first magnetic material includes multiple magnetized materials, the first heat dissipation layer 13 may be formed by uniformly mixing multiple materials of aluminum oxide, boron oxide or aluminum nitride that have been magnetized and deposited on the surface of the magnetic core body 11. Alternatively, the first heat dissipation layer 13 may also be composed of a film layer formed by depositing one material of aluminum oxide, boron oxide or aluminum nitride that has been magnetized on the surface of the magnetic core body 11, and a film layer formed by depositing another material on the surface of the magnetic core body 11; that is, the first heat dissipation layer 13 may also be composed of film layers formed by two or more materials. The structural composition of the second heat dissipation layer 14 may be the same as that of the first heat dissipation layer 13, which will not be repeated here.

[0134] In a specific embodiment, the material of the magnetic core body 11 includes a composite magnetic material, and the composite magnetic material includes 3-4 parts by mass of nickel-zinc alloy, 3-4 parts by mass of magnesium-zinc alloy, 13-16 parts by mass of iron oxide, and 12-15 parts by mass of iron. In this way, the magnetic permeability of the composite magnetic material is improved, so that the magnetic core body 11 made of the composite magnetic material has high saturation flux and high Curie temperature characteristics, and has low loss characteristics under high frequency conditions. In an embodiment of the present application, the composite magnetic material includes a nickel-zinc alloy, a magnesium-zinc alloy, iron oxide and iron, wherein the mass fraction of the nickel-zinc alloy can be 3 parts, 3.5 parts, 4 parts, etc., or a range value composed of any two of the above values, for example, 3 parts-3.5 parts, 3.5 parts-4 parts, etc.; the mass fraction of the magnesium-zinc alloy can be 3 parts, 3.4 parts, 4 parts, etc., or a range value composed of any two of the above values, for example, 3 parts-3.5 parts, 3.5 parts-4 parts, etc.; the mass fraction of iron oxide can be 13 parts, 14 parts, 16 parts, etc., or a range value composed of any two of the above values, for example, 13 parts-14 parts, 14 parts-16 parts, etc.; the mass fraction of iron can be 12 parts, 13 parts, 15 parts, etc., or a range value composed of any two of the above values, for example, 12 parts-13 parts, 13 parts-15 parts, etc.

[0135] Preferably, the composite magnetic material comprises 3.5 parts by mass of nickel-zinc alloy, 3.5 parts by mass of magnesium-zinc alloy, 13 parts by mass of iron oxide, and 14 parts by mass of iron.

[0136] The composite magnetic material may also include any one or more of manganese-zinc alloy, nickel-iron alloy, and iron-manganese alloy; wherein the mass fraction of manganese-zinc alloy is 2-4 parts, the mass fraction of iron-manganese alloy is 2-4 parts, and the mass fraction of nickel-iron alloy is 3-4 parts. Specifically, the mass fraction of manganese-zinc alloy can be 2 parts, 3 parts, 4 parts, etc., or a range value composed of any two of the above values, for example, 2 parts-3 parts, 3 parts-4 parts, etc.; the mass fraction of iron-manganese alloy can be 2 parts, 3 parts, 4 parts, etc., or a range value composed of any two of the above values, for example, 2 parts-3 parts, 3 parts-4 parts, etc.; the mass fraction of nickel-iron alloy can be 3 parts, 3.5 parts, 4 parts, etc., or a range value composed of any two of the above values, for example, 3 parts-3.5 parts, 3.5 parts-4 parts, etc.

[0137] Preferably, the composite magnetic material further comprises 3 parts by mass of manganese-zinc alloy, 2.5 parts by mass of iron-manganese alloy, and 3.5 parts by mass of nickel-iron alloy.

[0138] Preferably, the composite magnetic material may also include 0.5-1.5 parts by mass of silicon to reduce the probability of oxidation of the elemental substance and / or alloy in the composite magnetic material during the preparation process. Specifically, the mass fraction of silicon may be 0.5 parts, 1 parts, 1.5 parts, etc., or a range value composed of any two of the above values, for example, 0.5 parts-1 parts, 1 parts-1.5 parts, etc. Among them, the silicon component in the composite magnetic material is mainly elemental silicon, and contains a small amount of silicon oxide; wherein the content of silicon oxide is about 5%.

[0139] In the composite magnetic material, the magnetic permeability of each component is different at different frequencies, so that the composite magnetic material has good magnetic properties at different frequency states; among them, the magnetic permeability of magnesium-zinc alloy is higher at low frequency state below 1Khz, and the magnetic permeability of manganese-zinc alloy is higher at medium frequency state of 300Mhz-700Mhz; the magnetic permeability of nickel-zinc alloy is higher at high frequency state of 750Mhz-900Mhz; the magnetic permeability of nickel-iron alloy is higher at high frequency state of 800Mhz-1Ghz; both elemental iron and iron-manganese alloy are materials with high magnetism, and the magnetic properties of the alloy can be adjusted by controlling the ratio of iron and manganese, thereby increasing the magnetization intensity and enhancing the magnetic properties of the alloy; iron oxide provides the role of magnetic skeleton.

[0140] Specifically, the manganese-zinc alloy may include a structural formula of MnZn x The material, wherein x can be 0.5-2; the nickel-zinc alloy can include a structural formula of Niy Zn material, wherein y can be 1-2; the magnesium-zinc alloy can include a structural formula of MgZn z The material, wherein z can be 0.5-1; the iron-manganese alloy can include a structural formula of Mn c Fe e material, wherein c can be 1-3, and e can be 1-4.

[0141] In a specific embodiment, the raw materials of the composite magnetic material may include both the first raw material and the second raw material. Among them, the first raw material may include a variety of single substances, specifically including 1-2 parts by mass of iron, 0.5-1.5 parts by mass of nickel, 0.5-1.5 parts by mass of zinc, and 0.5-1.5 parts by mass of silicon. In the embodiment of the present application, the first raw material may include iron, nickel, zinc and silicon; wherein the mass fraction of iron may be 1 part, 1.5 parts, 2 parts, etc., or a range value composed of any two of the above values, for example, 1-1.5 parts, 1.5-2 parts, etc. The mass fraction of nickel may be 0.5 parts, 1 parts, 1.5 parts, etc., or a range value composed of any two of the above values, for example, 0.5-1 parts, 1 parts-1.5 parts, etc. The mass fraction of zinc can be 0.5 parts, 1 parts, 1.5 parts, etc., or a range value formed by any two of the above values, for example, 0.5 parts-1 parts, 1 parts-1.5 parts, etc. The mass fraction of silicon can be 0.5 parts, 1 parts, 1.5 parts, etc., or a range value formed by any two of the above values, for example, 0.5 parts-1 parts, 1 parts-1.5 parts, etc.

[0142] The second raw material may include a variety of oxides, specifically including 0.8-1.2 parts by mass of nickel oxide, and 0.8-1.2 parts by mass of magnesium oxide. In the embodiment of the present application, the second raw material may include nickel oxide and magnesium oxide; wherein the mass fraction of nickel oxide may be 0.8 parts, 1 parts, 1.2 parts, etc., or a range value composed of any two of the above values, for example, 0.8-1 parts, 1 parts-1.2 parts, etc. The mass fraction of magnesium oxide may be 0.8 parts, 1 parts, 1.2 parts, etc., or a range value composed of any two of the above values, for example, 0.8-1 parts, 1 parts-1.2 parts, etc.

[0143] Among them, the mass ratio of the first raw material to the second raw material is 2.3:1-1.3:1. In the implementation mode of the present application, by controlling the mass ratio of the first raw material and the second raw material in the above range, it is beneficial to regulate the amount of alloy formed in the magnetic material, so that the composite magnetic core material has a wider frequency domain, higher magnetic permeability, and smaller magnetic loss. Specifically, the mass ratio of the first raw material to the second raw material is any ratio of 1.3:1, 1.5:1, 1.8:1, 2:1, 2.3:1, etc., or a range value composed of any two of the above values, for example, 1.3:1-1.8:1, 1.5:1-2:1, 1.8:1-2.3:1, etc. Preferably, the mass ratio of the first raw material to the second raw material can be 1.5:1.

[0144] Further, the first raw material may also include 0.5-1.5 parts by mass of manganese and / or 0.5-1.5 parts by mass of magnesium; the second raw material may also include one or more of manganese manganate, ferric oxide and zinc oxide; wherein the mass fraction of manganese manganate is 1-1.5 parts, the mass fraction of ferric oxide is 0.3-0.8 parts, and the mass fraction of zinc oxide is 1-1.5 parts; to increase the types of alloys in the composite magnetic material obtained, so that the composite magnetic material has a higher magnetic permeability under multiple frequency states. Wherein, the mass fraction of manganese can be 0.5 parts, 1 parts, 1.5 parts, etc., or a range value composed of any two of the above values, for example, 0.5-1 parts, 1 parts-1.5 parts, etc. The mass fraction of magnesium can be 0.5 parts, 1 parts, 1.5 parts, etc., or a range value composed of any two of the above values, for example, 0.5-1 parts, 1 parts-1.5 parts, etc. The mass fraction of manganous manganate can be 1 part, 1.2 parts, 1.5 parts, etc., or a range value consisting of any two of the above values, for example, 1 part-1.2 parts, 1.2 parts-1.5 parts, etc. The mass fraction of ferric oxide can be 0.3 parts, 0.5 parts, 0.8 parts, etc., or a range value consisting of any two of the above values, for example, 0.3 parts-0.5 parts, 0.5 parts-0.8 parts, etc. The mass fraction of zinc oxide can be 1 part, 1.2 parts, 1.5 parts, etc., or a range value consisting of any two of the above values, for example, 1 part-1.2 parts, 1.2 parts-1.5 parts, etc.

[0145] Furthermore, the multiple windings of the winding group 2 can be enameled wires. The core of the enameled wire is a copper wire, and the insulating varnish layer is a material with heat dissipation performance, such as a graphite and polyamide resin composite material, to further improve the heat dissipation performance of the transformer. The thickness of the insulating varnish layer is 0.1mm-0.25mm, so as to minimize the thickness of the enameled wire and enhance the heat dissipation performance within the transformer insulation withstand voltage range that meets the standard requirements. Specifically, the thickness of the insulating varnish layer can be any value of 0.1mm, 0.14mm, 0.18mm, 0.22mm or 0.25mm; or a range value composed of any two of the above values, for example, 0.1mm-0.18mm, 0.14mm-0.22mm, 0.18mm-0.25mm, etc.

[0146] Specifically, Figure 2 As shown, the winding group 2 is arranged on the side surface of the magnetic core 1 along the interval between two adjacent turns of the air gap 12, and avoids the area of ​​the magnetic core 1 with poor heat dissipation, that is, the two ends of the magnetic core 1 and the area corresponding to the air gap 12, so as to reduce the adverse effect of the winding group 2 on the heat dissipation efficiency of the magnetic core 1.

[0147] like Figure 1 As shown, in a specific embodiment, the transformer may further include a first magnet 4 and a second magnet 5, and the magnetic core 1 is disposed between the first magnet 4 and the second magnet 5; the first magnet 4 and the second magnet 5 at both ends of the magnetic core 1 are used to reduce the magnetic leakage around the magnetic core 1, increase the concentration of the magnetic flux density, and thus improve the performance of the magnetic core 1. Specifically, the first magnet 4 and the second magnet 5 may be rectangular parallelepiped, and the first magnet 4 and the second magnet 5 may be integrally formed with the magnetic core body 11, or may be separately formed and then fixed to the magnetic core body 11.

[0148] Continue reading Figure 2 In a specific embodiment, the transformer may further include a magnetic conductive portion 6. The magnetic conductive portion 6 may be disposed around the side surface of the magnetic core 1 close to the first magnet 4, and the magnetic conductive portion 6 may also be disposed around the side surface of the magnetic core 1 close to the second magnet 5, so as to reduce the magnetic leakage phenomenon existing at the connection between the magnetic core 1 and the first magnet 4 and at the connection between the magnetic core 1 and the second magnet 5.

[0149] Specific, combined Figure 3a and Figure 3b , the magnetic conductive part 6 is annular and is sleeved at the connection between the two ends of the magnetic core 1 and the first magnet 4 and the second magnet 5. The inner side of the magnetic conductive part 6 is arranged close to the side wall of the magnetic core 1, and the outer side of the magnetic conductive part 6 is an inclined surface. Along the direction from the first magnet 4 to the magnetic core 1, the width of the magnetic conductive part 6 close to the first magnet 4 gradually decreases, and along the direction from the second magnet 5 to the magnetic core 1, the width of the magnetic conductive part 6 close to the second magnet 5 also gradually decreases; wherein, the width of the magnetic conductive part 6 is the distance between the outer side and the inner side along the radial direction Y of the magnetic core 1.

[0150] It can be understood that in a traditional transformer, the connection between the magnetic core 1 and the first magnet 4 and the second magnet 5 is at a right angle. This geometric connection will cause the magnetic field to not be completely closed, resulting in magnetic field leakage; and the saturation magnetic induction intensity at the connection is low, and the anti-saturation ability is low. The transformer provided in the present application is provided with a magnetic conductive portion 6 with an inclined surface at the connection between the magnetic core 1 and the first magnet 4 and the second magnet 5 to change the geometric shape of the connection, thereby improving the passing efficiency of the magnetic flux lines and effectively reducing the magnetic leakage phenomenon of the magnetic core 1 at the connection; thereby improving the conversion efficiency of the transformer.

[0151] Specifically, the angle θ between the inclined surface and the side surface of the magnetic core 1 is 30°-60°, so that the inclined angle is close to the magnetic field angle, so that the magnetic flux lines are more concentrated, and the leakage magnetic phenomenon is further reduced. Specifically, the angle θ between the inclined surface and the side surface of the magnetic core can be any value of 30°, 40°, 45°, 50° or 60°; or a range value composed of any two of the above values, for example, 30°-45°, 40°-50°, 45°-60°, etc.

[0152] Preferably, the angle θ between the inclined surface and the side surface of the magnetic core 1 is 40°-50°. Specifically, the angle θ between the inclined surface and the side surface of the magnetic core can be any value of 40°, 42°, 45°, 48° or 50°; or a range value composed of any two of the above values, for example, 40°-45°, 42°-48°, 45°-50°, etc.

[0153] Preferably, the inclined surface may be a plane or an arc surface, so that the magnetic conductive portion 6 can reduce the magnetic leakage phenomenon at the connection as much as possible; wherein the arc surface may be an inclined surface that is concave inwards.

[0154] Furthermore, the magnetic conductive portion 6 can be made of the same material with high magnetic conductivity as the magnetic core body 11 , thereby further improving the anti-saturation capability of the magnetic core 1 and enhancing the performance of the magnetic core 1 in a high-frequency state.

[0155] Specifically, along the length direction X, the height h of the magnetic conductive portion 6 is 1%-15% of the height of the magnetic core body 11; specifically, the height h of the magnetic conductive portion 6 can be any value of 1%, 5%, 10%, 12% or 15% of the height of the magnetic core body 11; or a range value composed of any two of the above values, for example, 1%-10%, 5%-12%, 10%-15%, etc.

[0156] Preferably, the height h of the magnetic conductive portion 6 can be 5%-10% of the height of the magnetic core body 11, so that the effect of the magnetic conductive portion 6 in reducing leakage magnetic flux is optimal; specifically, the height h of the magnetic conductive portion 6 can be any value of 5%, 7%, 8%, 9% or 10% of the height of the magnetic core body 11; or a range value composed of any two of the above values, for example, 5%-8%, 7%-9%, 8%-10%, etc.

[0157] In a specific embodiment, Figure 4d As shown, the height h of the magnetic conductive portion 6 may be the same as the height h1 of the first heat dissipation layer 13 or the height h2 of the second heat dissipation layer 14; or Figure 3a and Figure 3b As shown, the height h of the magnetic conductive portion 6 may be different from the height h1 of the first heat dissipation layer 13 or the height h2 of the second heat dissipation layer 14 , which is not limited in the embodiment of the present application.

[0158] The second aspect of the present invention further provides a magnetic core 1, which has the same technical features as the magnetic core 1 in the transformer of the first aspect, that is, the magnetic core 1 may include a magnetic core body 11, and an air gap 12 is provided on the side wall of the magnetic core body 11. The air gap 12 spirally extends from the first end 111 of the magnetic core body 11 to the second end 112 along the length direction X of the magnetic core body 11 to form a spiral air gap 12 structure on the magnetic core body 11; and the depth of the air gap 12 is less than the radius of the magnetic core body 11. It has the same advantages as the magnetic core 1 in the transformer of the first aspect.

[0159] See also Figure 6 , Figure 6 A schematic flow chart of a method for preparing a magnetic core provided in one embodiment of the present application; a third aspect of the present application further provides a method for preparing a magnetic core, which is used to prepare the magnetic core involved in any of the above embodiments; specifically comprising:

[0160] Step S11: providing a magnetic core matrix.

[0161] In one embodiment of the present application, the material of the magnetic core matrix can be a commercially available magnetic core matrix.

[0162] See also Figure 7 , Figure 7 for Figure 6Schematic diagram of the process of step S11 in the embodiment of the present application; in another embodiment of the present application, the magnetic core matrix can also be made by the following method, step S111: provide a composite magnetic material. The composite magnetic material can be the composite magnetic material involved in any of the above embodiments. Step S112: Die-cast the composite magnetic material to form a magnetic core matrix. Specifically, the composite magnetic material is placed in a mold and molded under high pressure to form a magnetic core matrix. Wherein, the molding pressure is 100Mpa-300Mpa; specifically, the molding pressure can be 100Mpa, 150Mpa, 200Mpa, 250Mpa, 300Mpa, etc., or a range value composed of any two of the above values, for example, 100Mpa-200Mpa, 150Mpa-250Mpa, 200Mpa-300Mpa, etc.

[0163] Step S12: cutting the side wall of the magnetic core substrate to form an air gap to obtain a magnetic core body.

[0164] Specifically, along the length direction X of the magnetic core matrix, a blade is used to spirally cut the side wall of the magnetic core matrix from one end to the other end of the magnetic core matrix, and the cutting depth is less than the radius of the magnetic core matrix, so as to form a spiral air gap 12. The air gap 12 spirally extends from one end of the magnetic core body 11 to the other end along the length direction X of the magnetic core 1; and the depth of the air gap 12 is less than the radius of the magnetic core body 11, so that the magnetic core body 11 can maintain its overall continuous structure.

[0165] After step S12, the method may further include: depositing a first magnetized material on a portion of the circumferential surface and / or the end face of the magnetic core body close to the first end 111 to form a first heat dissipation layer; and / or depositing a second magnetized material on a portion of the circumferential surface and / or the end face of the magnetic core body close to the second end 112 to form a second heat dissipation layer.

[0166] In the specific implementation process, at least one material of magnetized aluminum oxide, boron oxide or aluminum nitride can be deposited on a portion of the circumferential surface of the magnetic core body 11 near the first end 111 by coating, spraying or simulation setting to form a first heat dissipation layer 13, and deposited on a portion of the circumferential surface of the magnetic core body 11 near the second end 112 to form a second heat dissipation layer 14.

[0167] Of course, in other embodiments, at least one of the magnetized aluminum oxide, boron oxide or aluminum nitride materials may be deposited on the end surface of the first end 111 of the magnetic core body 11 to form a first heat dissipation layer 13, and deposited on the end surface of the magnetic core body 11 close to the second end 112 to form a second heat dissipation layer 14.

[0168] See also Figure 8a , Figure 8a for Figure 7Schematic diagram of the process of step S111 in FIG. 1 ; wherein the specific steps of providing the composite magnetic material are as follows:

[0169] Step S10: providing a first raw material and a second raw material.

[0170] The first raw material includes multiple single substances, specifically multiple metal single substances and silicon; the second raw material includes multiple oxides. The mass ratio of the first raw material to the second raw material is 2.3:1-1.3:1.

[0171] Specifically, in one embodiment of the present application, the first raw material includes 1-2 parts by weight of iron, 0.5-1.5 parts by weight of nickel, 0.5-1.5 parts by weight of zinc, and 0.5-1.5 parts by weight of silicon. The second raw material includes 0.8-1.2 parts by weight of nickel oxide and 0.8-1.2 parts by weight of magnesium oxide.

[0172] In another embodiment of the present application, the first raw material may also include 1-2 parts of iron by mass, 0.5-1.5 parts of nickel by mass, 0.5-1.5 parts of zinc by mass, 0.5-1.5 parts of silicon by mass, 0.5-1.5 parts of manganese by mass, and 0.5-1.5 parts of magnesium by mass. The second raw material includes 0.8-1.2 parts of nickel oxide by mass, 0.8-1.2 parts of magnesium oxide by mass, 1-1.5 parts of manganese manganate by mass, 0.3-0.8 parts of ferric oxide by mass, and 1-1.5 parts of zinc oxide by mass. In other embodiments, the first raw material may also not include magnesium, and the second raw material may not include ferric oxide and zinc oxide. It may also be that the first raw material does not include manganese, and the second raw material does not include manganese manganate.

[0173] Step S20: mixing each metal element and at least one oxide other than the oxide of the element, respectively, and heating the mixture to obtain a plurality of material components.

[0174] Specifically, each metal element and each oxide except the oxide of the element, and a small amount of silicon are mixed and heated at 900°C-1500°C for 1h-3h; wherein the heating temperature and / or heating time are different for different raw materials; and the heating is carried out in an inert gas environment to prevent the metal element from being oxidized.

[0175] For example, iron is mixed with manganese manganate and a small amount of silicon and heated at 1000°C for 2 hours to make an iron-manganese alloy. Manganese is mixed with zinc oxide and a small amount of silicon and heated at 900°C for 2 hours to make a manganese-zinc alloy. Nickel is mixed with zinc oxide and a small amount of silicon and heated at 1100°C for 2 hours to make a nickel-zinc alloy. Magnesium is mixed with zinc oxide and a small amount of silicon and heated at 1200°C for 3 hours to make a magnesium-zinc alloy.

[0176] Step S30: Cooling and solidifying the various material components.

[0177] Specifically, the temperatures of different material components are cooled down respectively so as to solidify them into solids. For example, the iron-manganese alloy, the manganese-zinc alloy, the nickel-zinc alloy and the magnesium-zinc alloy are cooled down and solidified respectively to form solids.

[0178] Step S40: using a pulverizer to pulverize the various material components to obtain particles of the various material components.

[0179] Specifically, the various material components are crushed at a rotation speed of 300r / min-500r / min and a pressure of 150kpa-250kpa respectively; wherein, the rotation speeds and / or pressures are different for different material components so that the particle sizes of particles of different material components are different; the particle sizes of particles of the various material components are 500nm-1500nm.

[0180] For example, iron-manganese alloy is crushed at a speed of 300 r / min and a pressure of 150 kPa; manganese-zinc alloy is crushed at a speed of 300 r / min and a pressure of 200 kPa; nickel-zinc alloy is crushed at a speed of 500 r / min and a pressure of 250 kPa; magnesium-zinc alloy is crushed at a speed of 300 r / min and a pressure of 200 kPa. The above are only examples and do not limit the specific crushing speed and pressure of various materials.

[0181] Step S50: magnetizing and mixing particles of various material components to obtain a composite magnetic material.

[0182] Specifically, after magnetizing the particles of various material components under different magnetic field environments, magnetized particles of various material components are obtained. For example, in the embodiment of the present application, the iron-manganese alloy, the manganese-zinc alloy, the nickel-zinc alloy and the magnesium-zinc alloy are magnetized respectively to obtain the magnetized iron-manganese alloy, the manganese-zinc alloy, the nickel-zinc alloy and the magnesium-zinc alloy.

[0183] A material skeleton is provided. In the embodiment of the present application, the material skeleton is an iron oxide magnetic material skeleton. In the embodiment of the present application, the iron oxide magnetic material skeleton includes a nested three-layer or more annular structure. Manganese-zinc alloy, nickel-zinc alloy, nickel-iron alloy, and magnesium-zinc alloy are sequentially filled in the iron oxide magnetic material skeleton, and magnetic vibration is performed to obtain a nested three-dimensional composite magnetic material. The composite magnetic material includes a multi-layer annular magnetic material layer 10, and the multi-layer annular magnetic material layer 10 includes a first magnetic material layer 101, a second magnetic material layer 102, and a third magnetic material layer 103. Among them, the first magnetic material layer 101 may include a manganese-zinc alloy, and the first magnetic material layer 101 may be a single-layer structure or a multi-layer structure.

[0184] The second magnetic material layer 102 is disposed outside the first magnetic material layer 101, and the second magnetic material layer 102 includes a nickel-zinc alloy and / or a manganese-zinc alloy; and the second magnetic material layer 102 can be a single-layer structure or a multi-layer structure. Another magnetic material layer 10 can be disposed between the first magnetic material layer 101 and the second magnetic material layer 102.

[0185] The third magnetic material layer 103 is disposed outside the second magnetic material layer 102 and includes a nickel-iron alloy; and the third magnetic material layer 103 can be a single-layer structure or a multi-layer structure. Another magnetic material layer 10 can also be disposed between the second magnetic material layer 102 and the third magnetic material layer 103.

[0186] See also Figure 8b , Figure 8b for Figure 7 A flow chart of another embodiment of step S111 in FIG. 1 ; In another embodiment of the present application, the specific step of providing the composite magnetic material may also include:

[0187] Step S10 ′: providing a first raw material and a second raw material.

[0188] The same as the above embodiment, no further details will be given.

[0189] Step S20': mixing the first raw material and the second raw material and heating them to obtain an initial product.

[0190] Specifically, all metal elements, metal oxides and silicon are heated at 1000°C-1200°C for 1h-2h to obtain the initial product. The heating is carried out in an inert gas environment to prevent the metal elements from being oxidized. The heating temperature can be 1000°C, 1100°C, 1200°C, etc., or a range value composed of any two of the above values, for example, 1000°C-1100°C, 1100°C-1200°C, etc.; the heating time can be 1h, 1.5h, 2h, etc., or a range value composed of any two of the above values, for example, 1h-1.5h, 1.5h-2h, etc.

[0191] Specifically, in one embodiment, the first raw material includes 1-2 parts of iron by mass, 0.5-1.5 parts of nickel by mass, 0.5-1.5 parts of zinc by mass, and 0.5-1.5 parts of silicon by mass. The second raw material includes 0.8-1.2 parts of nickel oxide by mass, and 0.8-1.2 parts of magnesium oxide by mass. The first raw material and the second raw material are mixed in a mass ratio of 2.3: 1-1.3: 1, and then heat-treated in an inert gas environment to obtain an initial product. In an embodiment of the present application, the first raw material and the second raw material react during heating to form a mixture of nickel-zinc alloy, magnesium-zinc alloy, iron oxide, iron and silicon-containing material as an initial product.

[0192] Step S30': cooling and solidifying the initial product.

[0193] Specifically, the cooling temperature is controlled within the range of -20°C-10°C; wherein the cooling temperature can be controlled to -20°C, -10°C, 0°C, 10°C, etc., or a range value composed of any two of the above values, for example, -20°C-0°C, -10°C-10°C, etc.

[0194] Step S40': using a pulverizer to pulverize the solidified initial product to obtain mixed product particles.

[0195] Specifically, the solidified mixed product is crushed under the conditions of a rotation speed of 300r / min-500r / min and a pressure of 150kpa-250kpa to obtain mixed product particles. Specifically, the rotation speed can be 300r / min, 350r / min, 400r / min, 450r / min, 500r / min, etc., or a range value composed of any two of the above values, for example, 300r / min-400r / min, 350r / min-450r / min, 400r / min-500r / min, etc.; the pressure can be 150kpa, 200kpa, 250kpa, etc., or a range value composed of any two of the above values, for example, 150kpa-200kpa, 200kpa-250kpa, etc. Wherein, the particle size of the mixed product particles is 500nm-1500nm.

[0196] Step S50 ′: magnetizing and mixing the mixed product particles to obtain a composite magnetic material.

[0197] See also Fig. 9 , Fig. 9 A schematic flow chart of a method for preparing a transformer provided in an embodiment of the present application; a fourth aspect of the embodiment of the present application also includes a method for preparing a transformer, comprising the following steps:

[0198] Step S1: providing a magnetic core.

[0199] Specifically, the magnetic core 1 may be a magnetic core 1 prepared by the method for preparing the magnetic core of the third aspect. The magnetic core 1 has the same technical features as the magnetic core 1 of the third aspect, that is, the magnetic core 1 may include a magnetic core body 11, and an air gap 12 is provided on the side wall of the magnetic core body 11. The air gap 12 spirally extends from the first end 111 of the magnetic core body 11 to the second end 112 along the length direction X of the magnetic core body 11 to form a spiral air gap 12 structure on the magnetic core body 11; and the depth of the air gap 12 is less than the radius of the magnetic core body 11.

[0200] Step S2: Winding a plurality of windings on the surface between two adjacent turns of the air gap of the magnetic core to form a winding group.

[0201] Specifically, a plurality of enameled wires are spirally wound from the first end 111 of the magnetic core body 11 to the second end 112 along the interval between two adjacent turns of the air gap 12 to form the winding set 2 .

[0202] Step S3: Arrange a device frame outside the magnetic core and the winding assembly.

[0203] Specifically, the device skeleton can be formed outside the magnetic core 1 and the winding group 2 by integral injection molding. In the specific implementation process, the magnetic core 1 and the winding group 2 are first fixed in the mold and the input pins and output pins are reserved; then the epoxy resin mixed with the heat dissipation material is injected into the mold; finally, it is cooled and solidified at room temperature to form the device skeleton.

[0204] After step S1, the method further includes: forming a first magnet and a second magnet at two ends of the magnetic core along the length direction of the magnetic core, respectively, so that the magnetic core is located between the first magnet and the second magnet.

[0205] Specifically, the material of the first magnet 4 and the second magnet 5 may be the same as that of the core body 11. In some embodiments, if the first heat dissipation layer 13 and the second heat dissipation layer 14 are disposed on the circumferential surface at both ends of the core body 11, the first magnet 4 and the second magnet 5 may be integrally formed with the core body 11. In other embodiments, if the first heat dissipation layer 13 and the second heat dissipation layer 14 are disposed on the end surfaces at both ends of the core body 11, the first magnet 4 and the second magnet 5 may be separately formed with the core body 11 and then fixed at both ends of the core body 11.

[0206] After the step of forming the first magnet and the second magnet, the method further includes: depositing magnetic material on the side surface of the magnetic core close to the first magnet and / or the second magnet to form a magnetic conductive portion.

[0207] Specifically, the magnetic conductive portion 6 is annular, the inner side of the magnetic conductive portion 6 is arranged close to the side wall of the magnetic core 1, and the outer side of the magnetic conductive portion 6 is an inclined surface; and the width of the magnetic conductive portion 6 gradually decreases along the direction from the first magnet 4 and / or the second magnet 5 toward the magnetic core 1. The material of the magnetic conductive portion 6 can be the same as that of the magnetic core body 11.

[0208] The fifth aspect of the embodiment of the present application further provides an electronic device, comprising a circuit board and a transformer involved in any of the above embodiments, wherein the transformer is arranged on the circuit board. The electronic device effectively reduces the magnetic impedance of the magnetic core 1, thereby improving the anti-saturation ability of the magnetic core 1, and effectively reduces the loss, so that the transformer has a low loss characteristic under high-frequency working state.

[0209] The following are examples of the present application. The examples described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the art or in the product specifications shall be followed.

[0210] Example 1

[0211] Provide a first raw material and a second raw material; wherein the composition and mass ratio of the first raw material are: Mn:Fe:Ni:Zn:Mg:Si=1:2:1:2:1:1; the composition and mass ratio of the second raw material are: Mn 2 O 3 :MgO:NiO:Fe 2 O 3 =1:2:1:2; the mass ratio of the first raw material to the second raw material is 1.8:1.

[0212] All metal elements, metal oxides and silicon are heated in an inert gas environment at 1000° C. for 2 hours to obtain initial products; the initial products include manganese-zinc alloy, nickel-zinc alloy, nickel-iron alloy, magnesium-zinc alloy, iron oxide and iron.

[0213] The initial product was then cooled at 10°C.

[0214] Then, the solidified initial product is crushed at a speed of 300 r / min and a pressure of 250 kPa to obtain mixed product particles including manganese-zinc alloy, nickel-zinc alloy, nickel-iron alloy, magnesium-zinc alloy, iron oxide and iron. The particle size of the manganese-zinc alloy particles obtained by crushing is 600-1400 nm, the particle size of the nickel-zinc alloy particles obtained by crushing is 600-1500 nm, the particle size of the nickel-iron alloy particles obtained by crushing is 700-1400 nm, and the particle size of the magnesium-zinc alloy particles obtained by crushing is 600-1000 nm.

[0215] Finally, the mixed product particles are magnetized to obtain a composite magnetic material; wherein the prepared composite magnetic material includes manganese-zinc alloy (MnZn), nickel-zinc alloy (NiZn), nickel-iron alloy (FeNi), nickel-iron alloy (FeNi), magnesium-zinc alloy (MgZn), iron oxide (Fe 2 O 3 ), iron (Fe), silicon oxide (SiO 2 ) and silicon (Si). Among them, manganese zinc alloy (MnZn), nickel zinc alloy (NiZn), nickel iron alloy (FeNi), nickel iron alloy (FeNi), magnesium zinc alloy (MgZn), iron oxide (Fe 2 O 3 ), iron (Fe) mass ratio is: MnZn:NiZn:FeNi:MgZn:Fe 2 O 3 :Fe=3:3.5:3.5:3.5:14:13.

[0216] The transformer provided in Example 1 is manufactured by using the composite magnetic material through the steps of stamping, cutting, winding and fixed assembly. Specifically, the air gap 12 of the transformer provided in Example 1 is spiral, and the depth a of the air gap 12 is 20% of the radius of the magnetic core 1; the width b of the air gap 12 is 0.25 mm; and the distance d between two adjacent turns of the air gap 12 is 4 mm. Furthermore, a first heat dissipation layer 13 is provided on a portion of the surface of the magnetic core 1 close to the first magnet 4 in Example 1, and a second heat dissipation layer 14 is provided on a portion of the surface of the magnetic core 1 close to the second magnet 5; wherein the height of the first heat dissipation layer 13 and the second heat dissipation layer 14 is 0.03 mm. A magnetic conductive portion 6 is also provided on the side surface of the magnetic core 1 close to the first magnet 4 and the side surface of the magnetic core 1 close to the second magnet 5, and the height of the magnetic conductive portion 6 is 7.5% of the height of the magnetic core 1.

[0217] Specifically, Fig.10 and Fig.11 As shown, Fig.10 A curve diagram of the saturation magnetic induction intensity of the magnetic core of the transformer provided in Example 1 of the present application at different temperatures; Fig.11 This is a power loss curve diagram of the magnetic core of the transformer at different temperatures provided in Example 1 of the present application. Among them, Fig.10 The horizontal axis is temperature, the vertical axis is magnetic field intensity, the red curve is the saturation magnetic induction intensity curve, and the black curve is the lifetime magnetic induction intensity curve. Fig.11 The horizontal axis is temperature, the vertical axis is power loss, the black curve is the relationship between power loss and temperature at a frequency of 100kHz and a magnetic field strength of 300 millitesla (mT); the red curve is the relationship between power loss and temperature at a frequency of 100kHz and a magnetic field strength of 150mT; the green curve is the relationship between power loss and temperature at a frequency of 500kHz and a magnetic field strength of 150mT; the blue curve is the relationship between power loss and temperature at a frequency of 500kHz and a magnetic field strength of 300mT.

[0218] like Fig.10 and Fig.11 As shown, the magnetic core 1 in the transformer provided in Example 1 of the present application also has a higher saturation magnetic induction intensity at a higher temperature; and can reach 150mW / cm2 at 500Khz, 300mT, and 100°C. 3 Low loss characteristics.

[0219] Example 2

[0220] The preparation method of Example 2 is basically the same as that of Example 1, except that the composition and mass ratio of the first raw material are: Mn:Fe:Ni:Zn:Mg:Si=1:2:1:2:2:0.5; the mass ratio of the first raw material to the second raw material is 1.3:1; all metal elements, metal oxides and silicon are heated at 1200°C for 1 hour to obtain an initial product; the composition of the prepared composite magnetic material except silicon oxide and silicon and the mass ratio of other components are: MnZn:NiZn:FeNi:MgZn:Fe 2 O 3 :Fe =2:3:3.5:3.5:13:12. In addition, the depth a of the air gap 12 of the transformer provided in Embodiment 2 is 15% of the radius of the magnetic core 1.

[0221] Example 3

[0222] The preparation method of Example 3 is basically the same as that of Example 1, except that the composition and mass ratio of the first raw material are: Mn:Fe:Ni:Zn:Mg:Si=1:3:1:2:1:1.2; the composition and mass ratio of the second raw material are: Mn 2 O 3 :MgO:NiO:ZnO=2:2:1:1.5; the mass ratio of the first raw material to the second raw material is 2.3:1; the cooling temperature of the initial product is -20°C; the particle size of the iron-manganese alloy particles obtained by crushing is 700-1200nm; the components of the prepared composite magnetic material except silicon oxide and silicon and the mass ratio are: MnFe:NiZn:FeNi:MgZn:Fe 2 O 3 :Fe= 2:3:3:3.5:15:12. In addition, the distance d between two adjacent turns of the transformer provided in Embodiment 3 is 5 mm.

[0223] Example 4

[0224] The preparation method of Example 4 is basically the same as that of Example 1, except that the composition and mass ratio of the first raw material are: Mn:Fe:Ni:Zn:Mg:Si=1:3:1:2:2:1.5; the composition and mass ratio of the second raw material are: Mn 2 O 3 :MgO:NiO:Fe 2 O 3 =1:2:2:1; the mass ratio of the first raw material to the second raw material is 1.8:1; the cooling temperature of the initial product is -10°C; the particle size of the iron-manganese alloy particles obtained by crushing is 700-1200nm; the components of the prepared composite magnetic material except silicon oxide and silicon and the mass ratio are: MnZn:NiZn:MnFe:MgZn:Fe 2O 3 :Fe= 3:3.5:3:3.5:16:15. In addition, the width b of the air gap 12 of the transformer provided in Embodiment 4 is 0.5 mm.

[0225] Example 5

[0226] The preparation method of Example 5 is substantially the same as that of Example 1, except that the transformer provided in Example 5 is not provided with the first heat dissipation layer 13 and the second heat dissipation layer 14 .

[0227] Example 6

[0228] Weigh appropriate amounts of the first raw material and the second raw material respectively, form a powder material through ball milling, pressing and sintering, and then perform magnetic sintering on the powder material to obtain a magnetic material; finally, use the magnetic material to prepare the transformer provided in Example 6; wherein the composition and mass ratio of the first raw material are: Fe:Ni=1:1; the composition and mass ratio of the second raw material are: Fe:Ni=1:1; 2 O 3 :NiO=1:2; the mass ratio of the first raw material to the second raw material is 3:1; the composition and mass ratio of the prepared magnetic material are: FeNi:Fe 2 O 3 :Fe=100:1:1.

[0229] Specifically, the depth a of the air gap 12 of the transformer provided in Example 6 is 20% of the radius of the magnetic core 1; the width b of the air gap 12 is 0.25 mm; and the distance d between two adjacent turns of the air gap 12 is 4 mm.

[0230] Example 7

[0231] The preparation method of Example 7 is basically the same as that of Example 1, except that the depth a of the air gap 12 of the transformer provided by Example 7 is 30% of the radius of the magnetic core 1; the width b of the air gap 12 is 0.5 mm; and the distance d between two adjacent turns of the air gap 12 is 5 mm.

[0232] Example 8

[0233] The preparation method of Example 8 is basically the same as that of Example 1, except that the depth a of the air gap 12 of the transformer provided by Example 8 is 10% of the radius of the magnetic core 1; the width b of the air gap 12 is 0.1 mm; and the distance d between two adjacent turns of the air gap 12 is 3 mm.

[0234] Example 9

[0235] The preparation method of Example 9 is basically the same as that of Example 1, except that appropriate amounts of the first raw material and the second raw material are weighed respectively; wherein the composition and mass ratio of the first raw material are: Mn:Fe:Ni:Zn:Mg:Si=1:2:1:2:1:1; the composition and mass ratio of the second raw material are: Mn 2 O 3 :MgO:NiO: ZnO=1:2:1:2; the mass ratio of the first raw material to the second raw material is 1.8:1.

[0236] Then, manganese is mixed with zinc oxide and a small amount of silicon and heated at 900°C for 2 hours to make a manganese-zinc alloy. Nickel is mixed with zinc oxide and a small amount of silicon and heated at 1100°C for 2 hours to make a nickel-zinc alloy. Iron is mixed with nickel oxide and a small amount of silicon and heated at 1300°C for 2 hours to make a nickel-iron alloy. Magnesium is mixed with zinc oxide and a small amount of silicon and heated at 1200°C for 3 hours to make a magnesium-zinc alloy.

[0237] Then, the manganese-zinc alloy, nickel-zinc alloy, nickel-iron alloy and magnesium-zinc alloy are cooled at different temperatures respectively; among which, the cooling temperature of the manganese-zinc alloy is -10°C, the cooling temperature of the nickel-zinc alloy is -15°C, the cooling temperature of the nickel-iron alloy is -20°C, and the cooling temperature of the magnesium-zinc alloy is -20°C.

[0238] Then, the manganese-zinc alloy was crushed at a rotation speed of 300 r / min and a pressure of 200 kPa; the nickel-zinc alloy was crushed at a rotation speed of 500 r / min and a pressure of 250 kPa; the nickel-iron alloy was crushed at a rotation speed of 400 r / min and a pressure of 300 kPa; and the magnesium-zinc alloy was crushed at a rotation speed of 300 r / min and a pressure of 200 kPa.

[0239] The particles of various material components were magnetized under different magnetic field environments. Specifically, the manganese-zinc alloy was magnetized under a magnetic field strength of 85 Gauss, the nickel-zinc alloy was magnetized under a magnetic field strength of 115 Gauss, the nickel-iron alloy was magnetized under a magnetic field strength of 135 Gauss, and the magnesium-zinc alloy was magnetized under a magnetic field strength of 70 Gauss.

[0240] Under the protection of inert gas, the iron oxide is pressurized and heated to obtain a heated product, wherein the pressure increases from 5 kPa to 50 kPa, the speed increase is 1 kPa / 5 min, the temperature is 250°C, and the time is 1 hour. A mist coagulant silica gel is applied to the heated product to obtain an iron oxide material skeleton; wherein the mass ratio of the heated product to the mist coagulant is 12:1.

[0241] The iron oxide material skeleton is magnetized to obtain an iron oxide magnetic core material skeleton, so that the magnetic field strength at the center of the iron oxide magnetic material skeleton is 35 Gauss, and the magnetic field strength at the edge is 175 Gauss; then the iron oxide magnetic skeleton is sequentially mixed with manganese-zinc alloy, nickel-zinc alloy, nickel-iron alloy, and magnesium-zinc alloy, and magnetically vibrated to obtain a composite magnetic material.

[0242] High magnification scanning electron microscope image of composite magnetic material Fig.12 As shown, Fig.12 The microstructure diagram of the composite magnetic material of the magnetic core body in the transformer provided in Example 9 of the present application: In the specific embodiment, the microstructure of the composite magnetic material includes a plurality of ring-shaped magnetic material layers 10, and the plurality of ring-shaped magnetic material layers 10 are nested in sequence from the center along the radial direction Y outward to enhance the magnetic permeability of the composite magnetic material and reduce the magnetic loss of the magnetic core 1; in addition, it can also play a filtering role.

[0243] Specifically, the multi-layered magnetic material layer 10 includes a first magnetic material layer 101, a second magnetic material layer 102 and a third magnetic material layer 103. The first magnetic material layer 101 may include a manganese-zinc alloy, and may be a single-layer structure or a multi-layer structure.

[0244] The second magnetic material layer 102 is disposed outside the first magnetic material layer 101, and the second magnetic material layer 102 includes a nickel-zinc alloy and / or a manganese-zinc alloy; and the second magnetic material layer 102 can be a single-layer structure or a multi-layer structure. Another magnetic material layer 10 can be disposed between the first magnetic material layer 101 and the second magnetic material layer 102.

[0245] The third magnetic material layer 103 is disposed outside the second magnetic material layer 102 and includes a nickel-iron alloy; and the third magnetic material layer 103 can be a single-layer structure or a multi-layer structure. Another magnetic material layer 10 can also be disposed between the second magnetic material layer 102 and the third magnetic material layer 103.

[0246] Comparative Example 1

[0247] The transformer provided in Comparative Example 1 is prepared by using the same magnetic material as in Example 6 through steps such as stamping, cutting, winding, and fixing and assembling; specifically, Fig.13 As shown, Fig.13 This is a cross-sectional view of the transformer provided in Comparative Example 1 along line AA; the structure of the air gap 12 of the transformer provided in Comparative Example 1 is different from that in Example 6, and the structure of the air gap 12 in Comparative Example 1 is a cylindrical segment surface, which separates the magnetic core 1 into a plurality of separate cylindrical sub-core segments, that is, the air gap 12 completely cuts off the magnetic core 1; specifically, the width of the air gap 12 is 0.25 mm.

[0248] The performance tests of the transformers provided in Examples 1-9 and Comparative Example 1 were respectively carried out; specifically, the magnetic permeability of the core 1 was measured at 25°C and a magnetic field strength of B<0.25mT; the saturation magnetic induction intensity Bs of the core 1 was measured at 1200A / m, 50Hz, and 100°C; the magnetic loss was measured at 500Khz, 300mT, and 100°C; and the conversion efficiency was measured at 100°C.

[0249] The components of each of Examples 1-9 and Comparative Example 1 are shown in Table 1, and the structural parameters of Examples 1-9 and Comparative Example 1 are shown in Table 2:

[0250] Table 1 Sample composition

[0251]

[0252] Table 2 Sample structure parameters

[0253]

[0254] The following are performance test results of transformers provided in some embodiments of the present application and traditional transformers:

[0255] Table 3 Sample performance test results

[0256]

[0257] It can be seen from the performance test results that, compared with the transformer of comparative example 1, the magnetic permeability and saturation magnetic induction intensity of the magnetic core 1 in the transformers of examples 1 to 9 provided in the embodiments of the present application are significantly improved, and the magnetic loss is significantly reduced.

[0258] Combining Table 2 and Table 3, by comparing Example 6 with Comparative Example 1, it can be seen that, in the case of using conventional magnetic materials, the air gap 12 in the transformer provided by the present application is conducive to improving the anti-saturation ability of the magnetic core 1 and reducing magnetic loss. By comparing Examples 1-4 with Example 5, it can be seen that the heat dissipation layer is conducive to improving the conversion efficiency of the transformer at high temperatures.

[0259] Combining Table 1 and Table 3, it can be seen that nickel-zinc alloy and nickel-iron alloy are beneficial to improving the magnetic permeability and saturation magnetic induction intensity of the magnetic core under high frequency state.

[0260] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A transformer, characterized in that: include: A magnetic core, comprising a magnetic core body, an air gap is arranged on the side wall of the magnetic core body, the air gap spirally extends from the first end of the magnetic core body to the second end along the length direction of the magnetic core body; and the depth of the air gap is less than the radius of the magnetic core body, so that the magnetic core will not be completely cut off by the air gap; A winding group is arranged on the surface of the magnetic core between two adjacent turns of the air gap; the winding group includes a plurality of windings; An equipment frame, which is arranged outside the magnetic core and the winding group; A first magnet and a second magnet; the magnetic core is disposed between the first magnet and the second magnet; The magnetic conductive portion is disposed around the side surface of the magnetic core close to the first magnet and / or the second magnet; along the length direction of the magnetic core, the height of the magnetic conductive portion is 1%-15% of the height of the magnetic core.

2. The transformer according to claim 1, characterized in that: The magnetic conductive portion is annular, the inner side surface of the magnetic conductive portion is arranged closely against the side wall of the magnetic core, and the outer side surface of the magnetic conductive portion is an inclined surface; and along the direction of the first magnet and / or the second magnet toward the magnetic core, the width of the magnetic conductive portion gradually decreases.

3. The transformer according to claim 1, characterized in that: Along the length direction of the magnetic core, the height of the magnetic conductive portion is 5%-10% of the height of the magnetic core.

4. The transformer according to claim 2, characterized in that: The included angle between the inclined surface and the side surface of the magnetic core is 30°-60°.

5. The transformer according to claim 2, characterized in that: The included angle between the inclined surface and the side surface of the magnetic core is 40°-50°.

6. The transformer according to claim 4 or 5, characterized in that: The inclined surface is a plane or a curved surface.

7. The transformer according to claim 1, characterized in that: The depth of the air gap is 10%-30% of the radius of the magnetic core body.

8. The transformer according to claim 7, characterized in that: The depth of the air gap is 15%-25% of the radius of the magnetic core body.

9. The transformer according to claim 1, characterized in that: The width of the air gap is 0.1 mm-0.5 mm.

10. The transformer according to claim 9, characterized in that: The width of the air gap is 0.2 mm-0.4 mm.

11. The transformer according to claim 1, characterized in that: The distance between two adjacent turns of the air gap is 3mm-5mm.

12. The transformer according to claim 11, characterized in that The distance between two adjacent turns of the air gap is 3.5 mm-4.5 mm.

13. The transformer according to claim 1, characterized in that: Also includes: A first heat dissipation layer and / or a second heat dissipation layer, wherein the first heat dissipation layer is arranged on a partial circumferential surface and / or a first end surface of the magnetic core body close to the first end; and the second heat dissipation layer is arranged on a partial circumferential surface and / or a second end surface of the magnetic core body close to the second end.

14. The transformer according to claim 13, characterized in that: The material of the first heat dissipation layer includes a first magnetic material, and / or, The material of the second heat dissipation layer includes a second magnetic material.

15. The transformer according to claim 14, characterized in that The first magnetizable material comprises at least one of magnetized aluminum oxide, boron oxide or aluminum nitride; or The second magnetized material includes at least one of magnetized aluminum oxide, boron oxide, or aluminum nitride.

16. The transformer according to claim 1, characterized in that The material of the magnetic core body includes a composite magnetic material, and the composite magnetic material includes: 3-4 parts by weight of nickel-zinc alloy, 3-4 parts by weight of magnesium-zinc alloy, 13-16 parts by weight of iron oxide, and 12-15 parts by weight of iron.

17. The transformer according to claim 16, characterized in that The nickel-zinc alloy comprises a material having a structural formula of NiyZn, wherein y is 1-2; and / or, The magnesium-zinc alloy includes a material with a structural formula of MgZnz, wherein z is 0.5-1.

18. The transformer according to claim 16 or 17, characterized in that: The composite magnetic material includes any one or more of manganese-zinc alloy, nickel-iron alloy, and iron-manganese alloy, wherein the mass fraction of the manganese-zinc alloy is 2-4 parts, the mass fraction of the nickel-iron alloy is 3-4 parts, and the mass fraction of the iron-manganese alloy is 2-4 parts.

19. The transformer according to claim 18, characterized in that The composite magnetic material further comprises 0.5-1.5 parts by mass of a silicon-containing substance, wherein the silicon-containing substance comprises elemental silicon and / or silicon oxide.

20. The transformer according to claim 18, characterized in that The microstructure of the composite magnetic material comprises: The multi-layered magnetic material layer is nested in sequence from the center along the radial direction outwards.

21. The transformer according to claim 20, characterized in that The multi-layered magnetic material layer comprises: A first magnetic material layer, wherein the first magnetic material layer comprises a manganese-zinc alloy; A second magnetic material layer, arranged outside the first magnetic material layer, wherein the second magnetic material layer comprises a nickel-zinc alloy and / or a manganese-zinc alloy; The third magnetic material layer is arranged outside the second magnetic material layer in an annular manner, and the third magnetic material layer includes a nickel-iron alloy.

22. The transformer according to claim 16, characterized in that The magnetic core body comprises a composite magnetic material, and the raw materials of the composite magnetic material include: A first raw material, the first raw material comprising 1-2 parts by weight of iron, 0.5-1.5 parts by weight of nickel, 0.5-1.5 parts by weight of zinc, and 0.5-1.5 parts by weight of silicon; The second raw material comprises 0.8-1.2 parts by weight of nickel oxide and 0.8-1.2 parts by weight of magnesium oxide.

23. The transformer according to claim 22, characterized in that The first raw material includes 0.5-1.5 parts by weight of manganese and / or 0.5-1.5 parts by weight of magnesium; The second raw material includes one or more of manganous manganate, ferric oxide and zinc oxide, wherein the mass fraction of the manganous manganate is 1 part to 1.5 parts, the mass fraction of the ferric oxide is 0.3 parts to 0.8 parts, and the mass fraction of the zinc oxide is 1 part to 1.5 parts.

24. The transformer according to claim 22 or 23, characterized in that: The mass ratio of the first raw material to the second raw material is 2.3:1-1.3:

1.

25. A method for preparing a transformer, characterized in that: include: A magnetic core is provided; the magnetic core comprises a magnetic core body, an air gap is arranged on the side wall of the magnetic core body, the air gap spirally extends from the first end of the magnetic core body to the second end along the length direction of the magnetic core body; and the depth of the air gap is less than the radius of the magnetic core body, so that the magnetic core will not be completely cut off by the air gap; A first magnet and a second magnet are respectively formed at two ends of the magnetic core along the length direction of the magnetic core, so that the magnetic core is located between the first magnet and the second magnet; Depositing magnetic material on the side surface of the magnetic core close to the first magnet and / or the second magnet to form a magnetic conductive portion, wherein the height of the magnetic conductive portion is 1%-15% of the height of the magnetic core; Winding a plurality of windings on the surface between two adjacent turns of the air gap of the magnetic core to form a winding group; An equipment skeleton is arranged outside the magnetic core and the winding group.

26. The method for preparing a transformer according to claim 25, characterized in that: The magnetic conductive portion is annular, the inner side surface of the magnetic conductive portion is arranged closely against the side wall of the magnetic core, and the outer side surface of the magnetic conductive portion is an inclined surface; and along the direction of the first magnet and / or the second magnet toward the magnetic core, the width of the magnetic conductive portion gradually decreases.

27. The method for preparing a transformer according to claim 25, characterized in that: The preparation method of the magnetic core comprises: providing a magnetic core substrate; The side wall of the magnetic core substrate is cut to form an air gap to obtain the magnetic core body; the air gap spirally extends from the first end of the magnetic core body to the second end along the length direction of the magnetic core body; and the depth of the air gap is less than the radius of the magnetic core body.

28. The method for preparing a transformer according to claim 27, characterized in that: Providing a magnetic core matrix comprises: Providing a composite magnetic material; the composite magnetic material is the composite magnetic material in the transformer according to any one of claims 16 to 24; The composite magnetic material is die-cast to form a magnetic core matrix.

29. The method for preparing a transformer according to claim 28, characterized in that: The step of providing the composite magnetic material specifically comprises: Providing a first raw material and a second raw material; wherein the first raw material includes a plurality of single substances, and the single substances specifically include a plurality of metal single substances and silicon; and the second raw material includes a plurality of oxides; Respectively mixing each of the metal elements and at least one of the oxides other than the oxide of the element and heating them to obtain a plurality of material components; Cooling and solidifying the multiple material components; Using a pulverizer to pulverize the plurality of material components to obtain particles of the plurality of material components; The plurality of material component particles are magnetized and mixed to obtain the composite magnetic material.

30. The method for preparing a transformer according to claim 29, characterized in that: The step of providing the composite magnetic material specifically comprises: Providing a first raw material and a second raw material; wherein the first raw material includes a plurality of single substances, and the single substances specifically include a plurality of metal single substances and silicon; and the second raw material includes a plurality of oxides; The first raw material and the second raw material are mixed and heated to obtain an initial product; Cooling and solidifying the initial product; Using a pulverizer to pulverize the solidified initial product to obtain mixed product particles; The mixed product particles are magnetized and mixed to prepare a composite magnetic material.

31. The method for preparing a transformer according to claim 27, characterized in that: Also includes: Depositing a first magnetized material on a partial circumferential surface and / or an end surface of the magnetic core body close to the first end to form a first heat dissipation layer; and / or, A second magnetized material is deposited on a portion of the circumferential surface and / or the end surface of the magnetic core body close to the second end to form a second heat dissipation layer.

32. An electronic device, characterized in that: It comprises a circuit board and the transformer according to any one of claims 1 to 24, wherein the transformer is arranged on the circuit board.

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