KR102400119B1 - Magnetic core, inductor and emi filter comprising the same - Google Patents

Abstract

The inductor according to an embodiment of the present invention has a toroidal shape and includes a first magnetic body including ferrite, and at least one receiving groove disposed above or below the first magnetic body and extending in the thickness direction, respectively. One second magnetic body, but at least one accommodating groove may have an arc-shaped planar shape.

Description

Magnetic core, inductor and EMI filter including the same

The present invention relates to a magnetic core, an inductor, and an EMI filter including the same.

An inductor is one of electronic components applied on a printed circuit board, and may be applied to a resonance circuit, a filter circuit, a power circuit, etc. due to electromagnetic characteristics.

On the other hand, the EMI (Electro Magnetic Interference) filter applied in the power board passes the signals necessary for circuit operation and removes noise.

1 shows a block diagram in which a general power board to which an EMI filter is applied is connected to a power source and a load.

The type of noise transmitted from the power board of the EMI filter shown in FIG. 1 is largely divided into 30 MHz to 1 GHz radiated noise radiated from the power board and 150 kHz to 30 MHz conductive noise conducted through the power line. .

A transmission method of conductive noise may be divided into a differential mode and a common mode. Among them, common mode noise returns in a large loop even if it is a small amount, so it can affect distant electronic devices. Such common mode noise is also caused by impedance imbalance of the wiring system, and becomes more pronounced in a high-frequency environment.

In order to remove common mode noise, the inductor applied to the EMI filter shown in FIG. 1 generally uses a toroidal-shaped magnetic core including a Mn-Zn-based ferrite material. Since the Mn-Zn-based ferrite has high magnetic permeability at 100 kHz to 1 MHz, common mode noise can be effectively removed.

2 shows a perspective view of a typical inductor 100 .

Referring to FIG. 2 , the inductor 100 may include a magnetic core 110 and a coil 120 wound on the magnetic core 110 .

The magnetic core 110 may have a toroidal shape, and the coil 120 includes a first coil 122 wound on the magnetic core 110 and a second coil wound to face the first coil 122 . A coil 124 may be included. Each of the first coil 122 and the second coil 124 may be wound on the upper surface S1 , the side surface S2 , and the lower surface S3 of the toroidal-shaped magnetic core 110 .

The magnetic core 110 may further include a bobbin (not shown) for insulating the coil 120 , and the coil 120 may be formed of a conductive wire whose surface is coated with an insulating material.

3 is an exploded perspective view of the magnetic core shown in FIG. 2 further including a bobbin, and FIGS. 4 ( a ) and 4 ( b ) are perspective views illustrating the process of the magnetic core shown in FIG. 3 .

Referring to FIG. 3 , the magnetic core 110 may be accommodated in the bobbin 130 . The bobbin 130 may include an upper bobbin 132 and a lower bobbin 134 .

Next, referring to FIG. 4A , as shown in FIG. 3 , the magnetic core 110 is disposed on the bottom surface of the lower bobbin 132 in a state in which the upper bobbin 132 , the magnetic core 110 and the lower bobbin 132 are provided. ) can be placed. Thereafter, the upper bobbin 131 may be coupled to the result shown in FIG. 4(a) as shown in FIG. 4(b). In this case, each component may be adhered to each other through an adhesive material.

EMI filters using these inductors may require high-order circuit configurations such as 3rd to 5th order according to the EMI performance standards required for each product. A high-frequency filter or the like may be additionally required. However, when the order of the circuit is increased or a separate high-frequency filter is mounted, there is a problem in that it is difficult to reduce the thickness of the product by the EMI filter.

An object of the present invention is to provide a magnetic core component capable of satisfying high-frequency characteristics without a high-frequency filter while having excellent EMI noise attenuation performance, and an inductor and EMI filter including the same.

The inductor according to an embodiment of the present invention has a toroidal shape and includes a first magnetic body including ferrite, and at least one receiving groove disposed above or below the first magnetic body and extending in the thickness direction, respectively. One second magnetic body, but at least one accommodating groove may have an arc-shaped planar shape.

For example, the at least one second magnetic body may have a shape corresponding to a corresponding receiving groove among the at least one receiving groove.

For example, the at least one second magnetic material may be plural, and each of the plurality of second magnetic materials may have different widths in a radial direction.

For example, the at least one second magnetic material may be plural, and any one of the plurality of second magnetic materials may have a length different from that of the other second magnetic material in a vertical direction.

For example, the at least one second magnetic material may be plural, and any one of the plurality of second magnetic materials may have a length different from that of the other second magnetic material in the circumferential direction.

For example, the at least one second magnetic material may include a plurality of magnetic material segments having an arc-shaped planar shape and at least partially overlapping each other in a vertical or radial direction.

For example, the at least one second magnetic body may include a core having an arcuate planar shape; and a coil wound around the core.

For example, the first magnetic material may include Mn-Zn-based ferrite, and the second magnetic material may include an Fe-Si-based metal ribbon or ceramic.

An EMI filter according to an embodiment of the present invention includes an inductor; and a capacitor, wherein the inductor has a toroidal shape and includes: a first magnetic body including ferrite; and at least one second magnetic body disposed above or below the first magnetic body and accommodated in each of at least one accommodating groove extending in the thickness direction, wherein the at least one accommodating groove has an arc-shaped planar shape. can

For example, the first magnetic material may include Mn-Zn-based ferrite, and the second magnetic material may include a plurality of Fe-Si-based metal ribbons at least partially overlapping each other in a vertical or radial direction.

The inductor and the EMI filter including the same according to the embodiment are provided with one or more heterogeneous magnetic materials serving as a resonator so that the resonant frequency can be adjusted in the core, so that the noise attenuation effect is excellent and the EMI filter having the same can have selective characteristics for a specific frequency.

1 shows a block diagram in which a general power board to which an EMI filter is applied is connected to a power source and a load.
2 shows a perspective view of a typical inductor.
3 is an exploded perspective view illustrating a case in which the magnetic core shown in FIG. 2 further includes a bobbin.
4 (a) and 4 (b) are perspective views illustrating the process of the magnetic core shown in FIG. 3 .
5 is a perspective view and a cross-sectional view of a magnetic core according to an embodiment of the present invention.
6 is a process diagram of the magnetic core of FIG. 5 .
7 is a graph showing the magnetic permeability and inductance of a ferrite material and a metal ribbon material.
8 is an exploded perspective view illustrating an example of a magnetic core according to another embodiment of the present invention.
9A to 9D show an example of a third magnetic body having two different types of receiving grooves according to another embodiment of the present invention.
10 shows an example of a third magnetic body having a plurality of receiving grooves and a magnetic core including the same according to another embodiment of the present invention.
11A to 11D show specific configuration examples of a fourth magnetic body according to another embodiment of the present invention.
12 is a view for explaining the effect of a magnetic core according to another embodiment of the present invention by comparing it with a magnetic core according to a comparative example.
13 is an example of an EMI filter including an inductor according to an embodiment.

Since the present invention may have various changes and may have various embodiments, specific embodiments will be illustrated and described in the drawings. However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

Terms including an ordinal number such as second, first, etc. may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the second component may be referred to as the first component, and similarly, the first component may also be referred to as the second component. and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being “connected” or “connected” to another component, it may be directly connected or connected to the other component, but it is understood that other components may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

In the description of the embodiments, each layer (film), region, pattern or structure is “on” or “under” the substrate, each layer (film), region, pad or patterns. The description that it is formed on includes all those formed directly or through another layer. The criteria for the upper/above or lower/lower layers of each layer will be described with reference to the drawings. In addition, since the thickness or size of each layer (film), region, pattern, or structure in the drawings may be changed for clarity and convenience of description, it does not fully reflect the actual size.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, the embodiment will be described in detail with reference to the accompanying drawings, but the same or corresponding components are given the same reference numerals regardless of reference numerals, and overlapping descriptions thereof will be omitted.

According to an embodiment of the present invention, the magnetic core may include a first magnetic body and a second magnetic body made of different materials. Here, the second magnetic body may be disposed on at least a partial surface of the first magnetic body, and may include a wound metal ribbon of a plurality of layers.

5 is a perspective view and a cross-sectional view of a magnetic core according to an embodiment of the present invention, and FIG. 6 is a process diagram of the magnetic core of FIG. 5 .

5, the magnetic core 200 includes a first magnetic body 210 and a second magnetic body 220, the first magnetic body 210 and the second magnetic body 220 are heterogeneous, the second magnetic body ( 220 may be disposed on at least a partial surface of the first magnetic body 210 . In this case, the second magnetic material 220 may have a higher saturation magnetic flux density than the first magnetic material 210 .

Here, the first magnetic material 210 may include ferrite, and the second magnetic material 820 may include a metal ribbon. Here, the magnetic permeability (μ) of ferrite may be 2,000 to 15,000, and the magnetic permeability (μ) of the metal ribbon may be 100,000 to 150,000. For example, the ferrite may be Mn-Zn-based ferrite, and the metal ribbon may be a Fe-based nanocrystalline metal ribbon. The Fe-based nanocrystalline metal ribbon may be a nanocrystalline metal ribbon including Fe and Si. The thickness of the metal ribbon may be 15 mm to 20 mm, but is not necessarily limited thereto.

At this time, the first magnetic body 210 and the second magnetic body 220 have a toroidal shape, respectively, and the second magnetic body 220 is a second outer magnetic body 222 disposed on the outer circumferential surface S2 of the first magnetic body 210 . and a second inner magnetic body 224 disposed on the inner circumferential surface S4 of the first magnetic body 210 .

In this case, the thickness of the second outer magnetic body 222 and the second inner magnetic body 224 is thinner than the thickness of the first magnetic body 210 , respectively. When at least one of the ratio between the thickness of the second outer magnetic body 222 and the thickness of the first magnetic body 210 and the ratio between the thickness of the second inner magnetic body 224 and the thickness of the first magnetic body 210 is adjusted, the magnetic core The permeability of (200) can be adjusted.

In order to manufacture such a magnetic core, two second magnetic bodies 222 and 224 are prepared, respectively, as shown in FIG. 6 . Each of the second magnetic bodies 222 and 224 may be formed of a resin material on a metal ribbon wound in a plurality of layers. Among the prepared second magnetic bodies 222 and 224, the second inner magnetic body 224 corresponding to the inner circumferential surface S4 of the toroidal-shaped first magnetic body 210 may be inserted into the hollow of the first magnetic body 210, The first magnetic body 210 may be inserted into the hollow of the second outer magnetic body 822 corresponding to the outer circumferential surface S2 again. Of course, the relative coupling order of the second magnetic bodies to the first magnetic body 210 is not affected even if it is changed.

At this time, the outer circumferential surface S2 of the first magnetic body 210 and the second outer magnetic body 222 and the inner circumferential surface S4 of the first magnetic body 210 and the second inner magnetic body 224 may be adhered by an adhesive. In this case, the adhesive may be an adhesive including at least one of an epoxy-based resin, an acrylic resin, a silicone-based resin, and a varnish. In this way, when different types of magnetic materials are joined using an adhesive, performance degradation does not occur even during physical vibration.

Here, each of the second magnetic materials 222 and 224 may include a metal ribbon that is wound a plurality of times and stacked in a plurality of layers, as shown in FIG. 5 . The thickness and magnetic permeability of the second magnetic materials 822 and 824 may vary depending on the number of layers of the laminated metal ribbon, and accordingly, the magnetic permeability of the magnetic core 200 may vary, and the magnetic core 200 may be applied to the EMI filter. Noise canceling performance may vary.

That is, as the thickness of the second magnetic materials 222 and 224 increases, noise removal performance may increase. Using this principle, the thickness of the second magnetic bodies 222 and 224 disposed in the area where the coil is wound is thicker than the thickness of the second magnetic body 222 and 224 disposed in the area where the coil is not wound. The number of layers of the ribbon can be adjusted.

The number of layers of the metal ribbon can be adjusted by the number of windings, the winding start point and the winding end point. The relationship between the starting point and the ending point of the winding based on the second outer magnetic body 222 disposed on the outer circumferential surface S2 of the first magnetic body 810 as shown in FIG. 5A will be described as follows. Of course, as described above, the second outer magnetic body 222 is in a state in which winding as well as the formation of a resin material (not shown) before being coupled to the first magnetic body 210 is completed as described above, but for convenience of explanation, the first magnetic body It is assumed that the winding is started based on a point on the outer periphery of (210).

In the case of winding the second outer magnetic body 222, which is a metal ribbon, when winding one turn from the winding start point, the second outer magnetic body 222 may include a metal ribbon of one layer, and to be wound two turns from the winding start point. In this case, the second outer magnetic material 222 may include a metal ribbon of two layers. On the other hand, when the winding start point and the winding end point are different, for example, when winding one and a half turns from the winding start point, the second outer magnetic body 222 is a region in which a metal ribbon is laminated as one layer and a metal ribbon is laminated as a second layer. area will be included. Alternatively, when winding two and a half turns from the starting point of winding, the second outer magnetic body 222 includes an area in which a metal ribbon is stacked in two layers and an area in which a metal ribbon is stacked in three layers. In this case, if the coil is disposed in an area with a larger number of stacked layers, the noise removal performance of the EMI filter to which the magnetic core 200 according to the embodiment of the present invention is applied can be further improved.

For example, when the magnetic core 200 has a toroidal shape and the first coil 122 and the second coil 124 are wound on the magnetic core 200 to be symmetrical to each other, the first magnetic body 210 is The first coil 122 is disposed in an area where the number of stacked layers of the second outer magnetic body 222 disposed on the outer circumferential surface is large, and the second inner magnetic body 224 disposed on the inner circumferential surface of the first magnetic body 210 is stacked. The second coil 124 may be disposed in an area having a large number of layers. Accordingly, both the first coil 122 and the second coil 124 may be disposed in an area having a large number of stacked layers in the second magnetic body 222 and 224 , and the first coil 122 may be disposed in an area having a small number of stacked layers. ) and the second coil 124 are not disposed, so that high noise removal performance can be obtained.

The second outer magnetic body 222 and the second inner magnetic body 224 are exemplified as having the same material and thickness, but is not limited thereto. The second outer magnetic material 222 and the second inner magnetic material 224 may have different materials or different magnetic permeability, and may have different thicknesses. Accordingly, the magnetic permeability of the magnetic core 200 may have various ranges.

Also, referring to FIG. 7 , it can be seen that a magnetic core including both a ferrite material and a metal ribbon material having different magnetic permeability for each frequency exhibits high inductance in a predetermined frequency region, and thus high noise removal performance can be obtained.

In the magnetic core 200 using the heterogeneous magnetic material described so far, the second magnetic body 220 in the form of a metal ribbon wound around at least a portion of the inner circumferential surface and the outer circumferential surface of the first magnetic body 210 is disposed. However, according to another embodiment of the present invention, although the magnetic core includes a heterogeneous magnetic material, at least a portion of one or more other magnetic materials may be disposed in the receiving groove disposed on the upper or lower side rather than the outer circumferential or inner circumferential surface of one magnetic body.

Hereinafter, for convenience of description, a magnetic body having a receiving groove is referred to as a third magnetic body, and a magnetic body at least partially accommodated in the receiving groove is referred to as a fourth magnetic body.

For example, the third magnetic material may have a toroidal shape. In addition, the receiving groove disposed in the third magnetic body may be disposed in at least one of an upper portion or a lower portion of the third magnetic body having a toroidal shape. Here, when the receiving groove is disposed above the third magnetic body, the receiving groove has an opening on the upper surface of the third magnetic body, and may extend in the thickness direction, that is, in the lower direction, and the receiving groove may be a blind hole or a through hole. . Conversely, when the accommodating groove is disposed under the third magnetic body, the accommodating groove may have an opening on the lower surface of the third magnetic body, and may extend upward. For example, the receiving groove may have an arc shape having the same curvature as that of the upper surface or the lower surface of the third magnetic body.

Meanwhile, at least a portion of the fourth magnetic body is accommodated in the receiving groove of the third magnetic body, and the accommodated portion may have a shape corresponding to the receiving groove to be accommodated in the receiving groove. For example, when the planar shape of the accommodating groove is an arc shape, the fourth magnetic body may also have a pillar shape having a planar arc shape.

The third magnetic material may include ferrite, and the fourth magnetic material may include a magnetic material different from ferrite, for example, a ceramic-based material or a metal ribbon. Here, the magnetic permeability (μ) of ferrite may be 2,000 to 15,000, and the magnetic permeability (μ) of the metal ribbon may be 100,000 to 150,000. For example, the ferrite may be Mn-Zn-based ferrite, and the metal ribbon may be a Fe-based nanocrystalline metal ribbon. The Fe-based nanocrystalline metal ribbon may be a nanocrystalline metal ribbon including Fe and Si. The thickness of the metal ribbon may be 15 mm to 20 mm, but is not necessarily limited thereto. In addition, the fourth magnetic body may include a core and a coil wound around the core. In this case, the core of the fourth magnetic material may be a single magnetic material, or may be a laminated metal ribbon or a magnetic material.

Hereinafter, specific shapes of the third magnetic body and the fourth magnetic body, and a combined shape of the third magnetic body and the fourth magnetic body will be described with reference to FIGS. 8 to 11 .

8 is an exploded perspective view illustrating an example of a magnetic core according to another embodiment of the present invention.

Referring to FIG. 8 , the magnetic core 300A according to the embodiment includes a third magnetic body 310 having a toroidal shape having a first accommodating groove 311 disposed thereon, and being accommodated in the first accommodating groove 311 . A fourth magnetic body 320 is included.

The first receiving groove 311 shares the center point of two concentric circles (ie, the inner circumferential surface and the outer circumferential surface) constituting the annular planar shape of the third magnetic body 310 on a plane (eg, x-y plane), but the centrifugal (or diameter) may have an arc shape having a thickness in the direction. For example, the planar shape of the first receiving groove 311 may or may not be the same along the thickness direction.

The height h2 in the thickness direction (eg, the z-axis direction) of the first receiving groove 311 may be lower than the height h1 in the thickness direction of the third magnetic body 310 . In this case, the first receiving groove 311 may be in the form of a blind hole. If the height h2 of the first accommodating groove 311 is the same as the height h1 of the third magnetic body 310 , the first accommodating groove 311 may have a through-hole shape. The first accommodating groove 311 may be integrally formed with the third magnetic body 310 through a mold having a protrusion corresponding to the shape of the first accommodating groove 311 , or a third first accommodating groove 311 manufactured in a toroidal shape. It may be formed by perforating the upper surface of the magnetic material.

Meanwhile, at least a portion of the fourth magnetic body 320 may be accommodated in the first receiving groove 311 . To this end, the fourth magnetic body 320 may have a shape suitable to be accommodated in the first receiving groove 311 . For example, the fourth magnetic body 320 has an arc-shaped planar shape having a curvature and an aspect ratio corresponding to the planar shape of the first receiving groove 311 to correspond to the first receiving groove 311, and the fourth magnetic body ( The planar area of the 320 may be the same as or smaller than the planar area of the first receiving groove 311 . In addition, when the height h3 in the thickness direction of the fourth magnetic body 320 is lower than or equal to the height h2 of the receiving groove, the fourth magnetic body 320 can be completely accommodated in the first receiving groove 311 . there is. For example, when the height h3 in the thickness direction of the fourth magnetic body 320 is lower than the height h2 of the receiving groove, the position of the fourth magnetic body 320 in the thickness direction can be adjusted in the receiving groove. there is. That is, the lower surface of the fourth magnetic body 320 may or may not contact the lower surface of the first receiving groove 311 .

On the other hand, when the height h3 in the thickness direction of the fourth magnetic body 320 is greater than the height h2 of the receiving groove, a portion of the fourth magnetic body 320 protrudes upward of the third magnetic body 310 . it could be

Of course, this shape is exemplary, and the shape of the fourth magnetic body 320 is not limited to any shape as long as it can be accommodated in the first receiving groove 311 .

According to another aspect of the present embodiment, a plurality of receiving grooves may be disposed in the third magnetic body to accommodate a plurality of fourth magnetic bodies, respectively. In this case, the plurality of accommodating grooves are spaced apart from each other in the third magnetic body, and their respective shapes and relative arrangement positions on a plane may be the same or at least some may be different. This will be described with reference to FIGS. 9A to 10 .

9A to 9D show an example of a third magnetic body having two different types of receiving grooves according to another embodiment of the present invention.

Referring to FIG. 9A , a second accommodating groove 312 and a third accommodating groove 313 are disposed on an upper portion of the third magnetic body 310B. Here, the second accommodating groove 312 and the third accommodating groove 313 may have different separation distances from each other in the outer diameter or inner diameter of the third magnetic body 310B in the centrifugal direction. For example, the second receiving groove 312 may be disposed closer to the outer diameter than the inner diameter of the third magnetic body (ie, D1 > D2) than the third receiving groove 313 .

Also, referring to FIG. 9B , a first accommodating groove 311 and a second accommodating groove 312 are disposed on the upper portion of the third magnetic body 310C. Here, the first receiving groove 311 and the second receiving groove 312 may have different lengths in the circumferential direction. For example, the circumferential length L1 of the second accommodating groove 312 may be longer than the circumferential length L2 of the first accommodating groove 311 .

Also, referring to FIG. 9C , a second accommodating groove 312 and a fifth accommodating groove 315 are disposed on the upper portion of the third magnetic body 310D. Here, the second accommodating groove 312 and the fifth accommodating groove 315 may have different widths in the centrifugal direction. For example, the distal width w1 of the second accommodating groove 312 may be narrower than the distal width w2 of the fifth accommodating groove 315 .

Also, referring to FIG. 9D , a sixth accommodating groove 316 and a seventh accommodating groove 317 are disposed on the upper portion of the third magnetic body 310E. Here, the sixth accommodating groove 316 and the seventh accommodating groove 317 may have different depths in the thickness direction (eg, the z-axis direction). For example, the thickness direction depth D3 of the sixth receiving groove 316 may be smaller than the thickness direction depth D4 of the seventh receiving groove 317 .

In the form of the plurality of accommodating grooves described above, each of the accommodating grooves is illustrated as not overlapping in the distal direction, but at least a portion of the accommodating grooves may overlap in the distal direction. In addition, in each of FIGS. 9A to 9D, the shape or arrangement position of any one receiving groove is different from any one of the distance from the outer or inner diameter, the length in the circumferential direction, the width in the centrifugal direction, and the depth in the thickness direction. Although shown as being, it may have two or more differences. This will be described with reference to FIG. 10 .

10 shows an example of a third magnetic body having a plurality of receiving grooves and a magnetic core including the same according to another embodiment of the present invention.

First, referring to FIG. 10A , the third magnetic body 310E has receiving grooves 312 , 313 , 315 , 316 , 317 , and 318 having a plurality of different shapes and arrangement positions. In FIG. 10B, the magnetic core 300B in which the fourth magnetic body 322, 323, 325, 326, 327, 328 of a shape corresponding to each of these receiving grooves 312, 313, 315, 316, 317, 318 is accommodated is shown. do. Of course, it is apparent to those skilled in the art that the magnetic core 300B is exemplary, and that the magnetic core according to the embodiment may have more or fewer accommodating grooves, or the relative positions between the accommodating grooves may be different if necessary.

Meanwhile, in FIG. 8 , it is assumed that the fourth magnetic body has an arc-shaped columnar magnetic body having a thickness in the centrifugal direction, but the shape of the fourth magnetic body according to the embodiment is not limited thereto. Hereinafter, the configuration of the fourth magnetic body will be described with reference to FIGS. 11A to 11D .

11A to 11D show specific configuration examples of a fourth magnetic body according to another embodiment of the present invention.

First, referring to FIG. 11A , the fourth magnetic material 320A may have a shape in which a plurality of magnetic material segments 321A, 322A, 323A having an arc-shaped column shape are overlapped in the thickness direction (eg, the Z-axis direction). there is.

Also, referring to FIG. 11B , the fourth magnetic body 320B may have a shape in which a plurality of magnetic body segments 321B, 322B, and 323B having an arc-shaped column shape are superimposed in a centrifugal direction.

Also, referring to FIG. 11C , the fourth magnetic body 320C may include a core 321C having an arc-shaped pillar shape and a coil 325C wound around the core 321C.

In addition, referring to FIG. 11D , in the fourth magnetic material 320D, a plurality of magnetic material segments 321D, 322D, 323D, and 324D having an arc-shaped column shape similar to that of FIG. 11A is a thickness direction (eg, Z-axis direction) ) to form a core, and the coil 325D may be wound around the core.

For example, the coils 325C and 325D in FIGS. 11C and 11D may be open coils. For example, when a plurality of magnetic material segments overlap to form at least a portion of the fourth magnetic material as shown in FIGS. 11A, 11B and 11D , the magnetic material segment may be a metal ribbon. In addition, the configuration of the above-described fourth magnetic material may be selectively applied according to desired values of resonant frequency and mutual inductance, which will be described later.

In addition, in fixing the fourth magnetic body to the receiving groove of the third magnetic body, an adhesive material may be used, or a fitting method may be applied by adjusting the difference between the inner diameter of the receiving groove and the outer diameter of the fourth magnetic body accommodated therein. .

Hereinafter, effects of the magnetic core including the third magnetic material and the fourth magnetic material according to another embodiment of the present invention will be described.

As shown in FIG. 10B , when at least one heterogeneous magnetic material (eg, a fourth magnetic material) is accommodated in one magnetic material (eg, a third magnetic material), each magnetic material has a capacitance component and an inductance component. It may act as a resonator. This means that each has a resonant frequency and has a mutual inductance component with respect to each other. For example, in FIG. 10B , the 4-2 magnetic material 322 is referred to as a first resonator, the 4-3 magnetic material 323 is referred to as a second resonator, and the 4-5 magnetic material 325 is referred to as a third resonator. A second mutual inductance component is generated between the magnetic material 310F and the second resonator, and a third mutual inductance component is generated between the third magnetic material 310F and the third resonator. Accordingly, when the magnetic core 300B according to the embodiment is applied to the EMI filter due to the effect of the mutual inductance component, the noise attenuation effect may be improved.

In addition, when the fourth magnetic material serving as a resonator has different inductance and capacitance components, each fourth magnetic material has a different resonant frequency. This will be described with reference to FIG. 12 . 12 is a view for explaining an effect of a magnetic core according to another embodiment of the present invention by comparing it with a magnetic core according to a comparative example. In FIG. 12 , it is assumed that four fourth magnetic bodies are accommodated in the third magnetic body.

Referring to FIG. 12 , when a magnetic core composed of a single magnetic material without heterogeneous magnetic material is used, only one resonance point is obtained due to the characteristics of the single magnetic material, but when the magnetic core according to the present embodiment is applied, the third magnetic material In addition to the resonance points of , there are more resonance points as many as the number of the fourth magnetic material. Having such a resonance point means that there is an effect of trapping a frequency corresponding thereto, so a large number of resonance points means that the frequency band that can be removed is diverse, which is also the fourth magnetic material without a separate high-frequency filter. It means that the high-frequency characteristic performance can be satisfied by adjusting the resonance frequency of

As a result, as in the embodiment, by accommodating the plurality of fourth magnetic materials in the third magnetic body, they have more mutual inductance components and resonance points compared to the cores of the same order, so that EMI noise attenuation performance is improved, and high frequencies of various bands are separated It can be attenuated without a filter.

Meanwhile, the inductor according to the above-described embodiment may be included in the line filter. For example, the line filter may be a line filter for noise reduction applied to an AC-to-DC converter. 13 is an example of an EMI filter including an inductor according to an embodiment.

Referring to FIG. 13 , the EMI filter 2000 may include a plurality of X-capacitors (Cx), a plurality of Y-capacitors (Cy), and an inductor (L).

The X-capacitor (Cx) is connected between the first terminal (P1) of the live line (LIVE) and the third terminal (P3) of the neutral line (NEUTRAL) and the second terminal (P2) of the live line (LIVE) and the neutral line ( NEUTRAL), respectively, disposed between the fourth terminals P4.

The plurality of Y-capacitors Cy may be disposed in series between the second terminal P2 of the live line LIVE and the fourth terminal P4 of the neutral line NEUTRAL.

The inductor L may be disposed between the first terminal P1 and the second terminal P2 of the live line LIVE and between the third terminal P3 and the fourth terminal P4 of the neutral line NEUTRAL. there is. Here, the inductor L may be the inductor 100 according to the above-described embodiment.

When common mode noise is introduced, the EMI filter 2000 removes the common mode noise through the combined impedance characteristics of a primary inductance and a Y-capacitor (Cy). Here, the primary-side inductance of the live line LIVE is to be obtained by measuring the inductance between the first and second terminals P1 and P2 while the third and fourth terminals P3 and P4 are open. The primary side inductance of the neutral line NEUTRAL is obtained by measuring the inductance between the third and fourth terminals P3 and P4 while the first and second terminals P1 and P2 are open. can be

When the differential mode noise is introduced, the EMI filter 2000 removes the differential mode noise by using a combined impedance characteristic of a leakage inductance and an X-capacitor (Cx). Here, the leakage inductance of the live line LIVE can be obtained by measuring the inductance between the first and second terminals P1 and P2 while the third and fourth terminals P3 and P4 are shorted. In addition, the leakage inductance of the neutral line NEUTRAL may be obtained by measuring the inductance between the third and fourth terminals P3 and P4 while the first and second terminals P1 and P2 are short-circuited.

The inductor of the EMI filter 2000 according to the embodiment corresponds to the inductor according to the above-described embodiments.

The description of each of the above-described embodiments may be applied to other embodiments as long as content does not conflict with each other.

In the above, the embodiment has been mainly described, but this is only an example and does not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are not exemplified above in a range that does not depart from the essential characteristics of the present embodiment. It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiment may be implemented by modification. And differences related to such modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

100: inductor
110: magnetic core
120: coil
200, 300A, 300B: magnetic core
210: first magnetic material
220: second magnetic material
310: third magnetic material
320: fourth magnetic material

Claims (11)

a first magnetic material having a toroidal shape and including ferrite; and
At least one second magnetic body disposed on the upper or lower portion of the first magnetic body and accommodated in each of at least one receiving groove extending in the thickness direction,
The at least one receiving groove has an arc-shaped planar shape,
The at least one second magnetic body is a plurality,
Each of the plurality of second magnetic materials is
Inductors with different widths in the diametric direction. delete delete a first magnetic material having a toroidal shape and including ferrite; and
At least one second magnetic body disposed on the upper or lower portion of the first magnetic body and accommodated in each of at least one receiving groove extending in the thickness direction,
The at least one receiving groove has an arc-shaped planar shape,
The at least one second magnetic body is a plurality,
Any one of the plurality of second magnetic material
An inductor having a length different from that of the other second magnetic material in a vertical direction. a first magnetic material having a toroidal shape and including ferrite; and
At least one second magnetic body disposed on the upper or lower portion of the first magnetic body and accommodated in each of at least one receiving groove extending in the thickness direction,
The at least one receiving groove has an arc-shaped planar shape,
The at least one second magnetic body is a plurality,
Any one of the plurality of second magnetic material
An inductor having a length different from that of the other second magnetic material in a circumferential direction. a first magnetic material having a toroidal shape and including ferrite; and
At least one second magnetic body disposed on the upper or lower portion of the first magnetic body and accommodated in each of at least one receiving groove extending in the thickness direction,
The at least one receiving groove has an arc-shaped planar shape,
the at least one second magnetic material
An inductor comprising a plurality of magnetic material segments having an arc-shaped planar shape and at least partially overlapping each other in a vertical or radial direction. a first magnetic material having a toroidal shape and including ferrite; and
At least one second magnetic body disposed on the upper or lower portion of the first magnetic body and accommodated in each of at least one receiving groove extending in the thickness direction,
The at least one receiving groove has an arc-shaped planar shape,
the at least one second magnetic material
a core having an arcuate planar shape; and
An inductor including a coil wound around the core. According to any one of claims 1, 4 to 7,
The first magnetic material includes Mn-Zn-based ferrite, and the second magnetic material includes an Fe-Si-based metal ribbon or a ceramic inductor. inductor; and
including a capacitor;
The inductor is
a first magnetic material having a toroidal shape and including ferrite; and
At least one second magnetic body disposed on the upper or lower portion of the first magnetic body and accommodated in each of at least one receiving groove extending in the thickness direction,
The at least one receiving groove has an arc-shaped planar shape,
The first magnetic body includes Mn—Zn based ferrite, and the second magnetic body includes a plurality of Fe—Si based metal ribbons at least partially overlapping each other in a vertical or radial direction. delete According to any one of claims 1, 4 to 7,
The at least one second magnetic body,
An inductor having a shape corresponding to a corresponding receiving groove among the at least one receiving groove.

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