Two-dimensional planar magnetic element

Abstract

The utility model belongs to the technical field of magnetic elements, and particularly relates to a two-dimensional plane magnetic element. The utility model discloses a magnetic element. Comprising a two-dimensional magnetic core and a winding, the magnetic core is of a two-dimensional structure, namely the ratio of the width to the thickness of the magnetic core is larger than 10. A nanocrystalline strip is specifically adopted; the winding structure is realized by using a printed PCB, and a closed-loop winding current structure is formed through mechanical contact or welding of a paper folding structure and a bonding pad. The magnetic core and the winding are combined to form a magnetic element, current is introduced into the winding, and a magnetic field is generated in the magnetic core to achieve the functions of magnetic energy storage, voltage transformation and filtering. According to the utility model, the eddy current loss can be reduced, the internal parasitic electric field is reduced through the flat design of the magnetic core, the loss is further reduced, and the dimension parameter and the dimension of the PCB printing type winding can be adjusted according to requirements.

Description

Technical Field

[0001] The utility model belongs to the technical field of magnetic elements, and in particular relates to a two-dimensional magnetic element. Background Art

[0002] Traditional magnetic components are large in size, resulting in a lot of wasted space in the system, and it takes a lot of time to select and assemble them properly. Existing two-dimensional magnetic components (including but not limited to inductors and transformers) can effectively reduce the system volume, make magnetic components two-dimensional, increase the operating frequency of magnetic components, and reduce core loss. Compared with traditional magnetic components (including but not limited to inductors and transformers), two-dimensional magnetic components have higher energy density, higher operating frequency, and lower loss.

[0003] However, simply making magnetic components two-dimensional will bring challenges of electromagnetic thermal coupling: under high frequency:

[0004] (1) When the physical size of the copper material exceeds the skin depth of the copper material at the operating frequency, a significant eddy current effect will occur inside the wire, causing the current to be distributed only on the surface of the wire, increasing the loss while reducing the value of the magnetic component. From a material point of view, copper material has better conductivity. According to the skin depth formula The skin depth of copper material is smaller and the skin effect is more serious. δ (skin depth): indicates the depth at which the current density in the conductor drops to 1 / e (about 36.8%) of the surface current density. The unit is meter (m). ρ (resistivity): The resistivity of the conductor material, which indicates the material's resistance to the flow of current. The unit is ohm-meter (Ω·m). f (frequency): The frequency of alternating current. The unit is Hertz (Hz). μ r (Relative permeability): The ratio of the magnetic permeability of a material to the magnetic permeability of vacuum μ0. μ0 (vacuum permeability): The magnetic permeability of a vacuum, approximately equal to 4π×10 -7 Henry per meter (H / m).

[0005] (2) Due to the high magnetic permeability of the material, the self-resonance frequency is very low and cannot be normally applied at higher frequencies.

[0006] (3) The core loss of the material increases at high frequencies, and the eddy current loss of the magnetic material is serious.

[0007] Two-dimensionalization of magnetic materials: Ferrite materials are mechanically brittle and cannot be made into planar magnetic component materials. Summary of the invention

[0008] The utility model aims to provide a two-dimensional planar magnetic element (including but not limited to inductors and transformers) with high energy density and low loss applicable to high-frequency conditions and a preparation method thereof.

[0009] The two-dimensional magnetic element provided by the utility model specifically comprises two parts, a two-dimensional magnetic core and a winding; its structure is shown in Figure 1 ;in:

[0010] The magnetic core adopts a two-dimensional structure; specifically, the ratio of the width of the core section to the thickness is greater than 10; through the analysis of the electromagnetic field inside the magnetic core material, it is found that the flatter the magnetic cross-section of the material, the higher the self-resonance frequency. Therefore, the two-dimensional structure of the magnetic core design can increase the operating frequency of the magnetic component and reduce eddy current losses. The internal parasitic electric field can be reduced by flattening the magnetic core design, thereby further reducing losses.

[0011] The winding structure is realized by using a printed PCB, and a closed winding current structure is formed by mechanical contact or welding between the origami structure and the pad.

[0012] The magnetic core and winding are combined to form a magnetic element. When current is passed through the winding, a magnetic field is generated inside the magnetic core to achieve functions such as storing magnetic energy, voltage transformation and filtering.

[0013] In the utility model, the core cross-sectional width: thickness is greater than 10, and a multi-layer structure is adopted, for example, three layers are respectively located at the top, middle and bottom positions, the middle forms a center column, the top and bottom form side columns, and form an EE core structure to provide a closed magnetic flux path; two independent windings are formed by PCB to realize the function of a common-mode magnetic element.

[0014] Furthermore, for example, the core material is nanocrystalline ribbon, the four middle ribbons are used as the core center column, and two nanocrystalline ribbons of the same size at the top and bottom are used as the core side columns; the three parts constitute the EE core structure.

[0015] The winding adopts a double winding provided by a PCB printed structure, that is, two independent windings, such as Figure 3 shown.

[0016] Compared with traditional technology, the utility model has significant advantages and beneficial effects:

[0017] (1) The two-dimensional design of the magnetic core improves the resonant frequency and operating frequency of the magnetic component, making it suitable for high-frequency applications.

[0018] (2) The winding is realized by using PCB structure, making full use of the space in the middle of the magnetic core. The energy density of the overall magnetic component is improved. The two-dimensional magnetic component of PCB winding avoids the problems of selection and matching system height during the assembly process of traditional winding magnetic components. The dimensional parameters of the magnetic component can be designed and optimized according to the overall solution, further increasing the integration of the system, that is, reducing the system volume and increasing the system reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1This is a schematic diagram of a 3D model of a two-dimensional magnetic element provided by the utility model.

[0020] Figure 2 This is a top view schematic diagram of the 3D model of the two-dimensional magnetic element provided by the utility model.

[0021] Figure 3 The winding of the two-dimensional magnetic element provided by the utility model adopts a printed PCB winding structure. The two colors represent two independent winding structures.

[0022] Figure 4 This is the impedance test data of a two-dimensional common-mode inductor with 4 turns, which proves that the two-dimensional magnetic component proposed in this article has a high resonant frequency and can be used in high-frequency scenarios. DETAILED DESCRIPTION

[0023] According to different parameter requirements, the dimension parameters of two-dimensional magnetic components (including but not limited to inductors and transformers), PCB printed winding dimensions, etc. can be adjusted accordingly.

[0024] An example of a two-dimensional magnetic element is provided. Figure 1 As shown:

[0025] The core material of the two-dimensional magnetic component is located at the top, middle and bottom to form the middle column and side columns, providing a closed magnetic flux path. The width of the middle column core is 218:1;

[0026] The winding is a printed PCB structure. The double winding structure of the magnetic element shown in the figure uses a double-layer PCB board to realize two independent winding structures, which can flow two independent currents.

[0027] The core material is made of nanocrystalline ribbons with a thickness of 20um. The four strips in the middle form a thickness of 80um and a width of 17.5mm as the core center column. The top and bottom have two nanocrystalline ribbons of the same size, both with a thickness of 40um, as the side columns. The three parts together constitute the EE core structure.

[0028] The winding adopts PCB printed structure to provide a double winding with 4 turns. The two different colors represent two independent windings. Figure 3 shown.

[0029] The core and winding are as follows Figure 1 The stacked structures shown are assembled to form a two-dimensional magnetic element. Figure 4 As shown, the resonant frequency of the impedance test of the magnetic component is 35 MHz, which shows that the high resonant frequency characteristics of the two-dimensional magnetic component can be applied to high-frequency scenarios.

Claims

1. A two-dimensional planar magnetic element, characterized in that: It includes two parts: a two-dimensional magnetic core and a winding; wherein: The magnetic core is a two-dimensional structure; that is, the ratio of the width to the thickness of the magnetic core cross section is greater than 10; The winding structure is realized by using a printed PCB, and a closed winding current structure is formed by mechanical contact or welding between the origami structure and the pad; The magnetic core and winding are combined to form a magnetic element. When current is passed through the winding, a magnetic field is generated in the magnetic core to store magnetic energy, transform voltage and filter. The magnetic core adopts a three-layer structure, which is located at the top, middle and bottom respectively. The middle forms a center column, and the top and bottom form side columns, forming an EE magnetic core structure to provide a closed magnetic flux path; two independent windings are formed through the PCB to realize the function of a common-mode magnetic component.

2. The two-dimensional planar magnetic element according to claim 1, characterized in that: The material of the magnetic core is nanocrystalline ribbon.

3. The two-dimensional planar magnetic element according to claim 1, characterized in that: The core uses four nanocrystalline ribbons in the middle column, and two nanocrystalline ribbons of the same size are used at the top and bottom respectively.

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