Integrated inductor, circuit assembly, and inverter

Abstract

An integrated inductor, a circuit assembly, and an inverter. The integrated inductor comprises: a first magnetic core (1), a second magnetic core (2), a third magnetic core (3), and a plurality of windings (4), wherein the first magnetic core (1) surrounds the second magnetic core (2), and the second magnetic core (2) is spaced apart from the first magnetic core (1); each wire turn of each winding (4) is wound around the first magnetic core (1) and the second magnetic core (2), any two windings (4) are spaced apart from each other, and a common-mode inductor is formed between each winding (4) and the first magnetic core (1); and no winding is wound around the third magnetic core (3), a closed magnetic path is formed between the region where the winding (4) is wound on the second magnetic core (2) and the third magnetic core (3), and a differential-mode inductor is formed between each winding (4) and the closed magnetic path. The first magnetic core mainly provides a common-mode component, and the second magnetic core mainly provides a differential-mode component. Such a configuration increases the sectional area of each magnetic core, thereby increasing paths of differential-mode and common-mode magnetic lines of force, such that the first magnetic core and the second magnetic core are not prone to saturation, thereby increasing a common-mode inductance value of the first magnetic core and a differential-mode inductance value of the second magnetic core. By configuring a third magnetic core, an air path through which a magnetic flux leakage travels is shortened, air magnetic resistance is reduced, a differential-mode magnetic flux is increased, and an inductance value of the integrated inductor is further increased.

Description

Integrated inductors, circuit components and inverters

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number: 2023230868747 and application date of November 13, 2023, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the field of inductors, and more specifically, to an integrated inductor, a circuit component, and an inverter. Background Art

[0004] In the related art, in the common-mode inductor of a high-power inverter, many differential common-mode integration solutions have been produced due to the good symmetry and large available space of the toroidal core.

[0005] The principle of the differential and common-mode integration solution is to add additional magnetic cores to provide a path for the differential-mode magnetic lines of force. At the same time, due to the air gap between the magnetic cores, the common-mode magnetic lines of force still flow along the original path, thereby increasing the differential-mode component without affecting the common-mode inductance, thereby achieving the purpose of differential and common-mode integration.

[0006] The above differential and common mode integration solution has the following problems: due to space limitations, the cross-sectional area of ​​the additional magnetic strip is small and the inductance value of the magnetic strip is low, resulting in the inductance value of the differential and common mode integration solution failing to meet the design requirements.

[0007] Summary of the Invention

[0008] The present application provides an integrated inductor, a circuit component, and an inverter, which can increase the inductance value of the integrated inductor without increasing the volume of the integrated inductor.

[0009] In a first aspect, the present application provides an integrated inductor, comprising:

[0010] a first magnetic core;

[0011] a second magnetic core, wherein the first magnetic core surrounds an outer ring of the second magnetic core, and the second magnetic core is spaced apart from the first magnetic core;

[0012] a plurality of windings, wherein each turn of each winding is wound around the first magnetic core and the second magnetic core, and any two windings are spaced apart, and a common-mode inductor is formed between the plurality of windings and the first magnetic core;

[0013] A third magnetic core is provided, wherein no winding is wound on the third magnetic core, a closed magnetic path is formed between the area of ​​the second magnetic core where the winding is wound and the third magnetic core, and a differential mode inductance is formed between each winding and the closed magnetic path.

[0014] According to the integrated inductor provided in the embodiment of the present application, on the one hand, by providing a first magnetic core and a second magnetic core, and the first magnetic core is wrapped around the outer ring of the second magnetic core, the differential and common mode magnetic circuits can be separated to a certain extent. The first magnetic core mainly provides a common mode component, and the second magnetic core mainly provides a differential mode component. Compared with the related art in which the same magnetic core provides both a common mode component and a differential mode component, the cross-sectional area of ​​the magnetic core is increased, thereby increasing the path of the differential mode magnetic lines of force and the common mode magnetic lines of force, making the first magnetic core and the second magnetic core less likely to saturate, thereby improving the common mode inductance of the first magnetic core and the differential mode inductance of the second magnetic core; on the other hand, by providing a third magnetic core, a closed magnetic path is formed between the third magnetic core and the area on which the winding is wound on the second magnetic core, so that the air path through which the leakage magnetic flux passes becomes shorter. After the air gap in the magnetic circuit is reduced, the air magnetic resistance is reduced, and the differential mode magnetic flux is increased, thereby further improving the inductance value of the integrated inductor.

[0015] According to one embodiment of the present application, the third magnetic core includes a plurality of ends, the plurality of ends extending toward the first magnetic core and the second magnetic core, and at least one of the ends is distributed on a side surface of the winding;

[0016] The area of ​​the second magnetic core located between the ends on both sides of any one of the windings forms a closed magnetic path with the third magnetic core.

[0017] According to one embodiment of the present application, the multiple end portions are all located in the inner ring of the second magnetic core, and there is an air gap between the multiple end portions and the inner peripheral wall of the second magnetic core.

[0018] According to one embodiment of the present application, the extension arm is arranged at the end and extends in a direction close to the first magnetic core. The extension arm is distributed on the side of the second magnetic core along the thickness direction of the second magnetic core, and the extension arm at least partially overlaps with the projection of the second magnetic core along the thickness direction of the second magnetic core.

[0019] According to one embodiment of the present application, the extension arm is arranged at the end and extends in a direction close to the outer peripheral wall of the first magnetic core. The extension arm is distributed on the side surfaces of the second magnetic core and the first magnetic core along the thickness direction of the second magnetic core. The extension arm partially overlaps with the projection of the second magnetic core along the thickness direction of the second magnetic core, and the extension arm at least partially overlaps with the projection of the first magnetic core along the thickness direction of the second magnetic core.

[0020] According to one embodiment of the present application, each of the plurality of windings has the same number of coil turns, and each of the plurality of windings has the same winding direction.

[0021] According to one embodiment of the present application, the first magnetic core and the second magnetic core are both closed ring-shaped, and the outer circumferential wall of the second magnetic core is spaced equidistant from the inner circumferential wall of the first magnetic core at all locations.

[0022] According to one embodiment of the present application, along the thickness direction of the first magnetic core, the height of the third magnetic core is less than or equal to the height of the winding.

[0023] According to one embodiment of the present application, the first magnetic core and the second magnetic core are both in a closed annular shape, and the plurality of windings are spaced apart and distributed along the circumference of the annular shape;

[0024] Each of the ends of the third magnetic core is located between two adjacent windings, and the area on the second magnetic core where any one of the windings is wound forms a closed magnetic path with the corresponding area of ​​the third magnetic core, wherein the corresponding area of ​​the third magnetic core is the area between the two ends on both sides of the winding.

[0025] According to one embodiment of the present application, the winding includes three;

[0026] The third magnetic core includes three sections distributed along the circumferential direction, the radial inner ends of the three sections are connected to the same position, and the radial outer ends of the three sections are located between two adjacent windings;

[0027] The area of ​​the second magnetic core where any one of the windings is wound forms a closed magnetic path with two of the three sections located on both sides of the winding.

[0028] According to one embodiment of the present application, the third magnetic core includes a plurality of arc-shaped magnetic cores, each of the arc-shaped magnetic cores includes two ends;

[0029] The two ends of the arc-shaped magnetic core are respectively located on both sides of the winding, and the area of ​​the second magnetic core where the winding is wound forms a closed magnetic path with the arc-shaped magnetic core.

[0030] According to one embodiment of the present application, the first magnetic core and the second magnetic core each include a first side and a second side that are oppositely disposed, the first side and the second side together form a closed shape, and the multiple windings are wound around one of the first sides;

[0031] The third magnetic core includes a plurality of strip-shaped magnetic cores spaced apart from each other, the strip-shaped magnetic cores extending toward the two first sides and located between two adjacent windings;

[0032] The strip magnetic core and the adjacent second side, as well as the area on the first side between the second side and the strip magnetic core, form a closed magnetic path; the two adjacent strip magnetic cores and the area on the first side between the two strip magnetic cores form a closed magnetic path.

[0033] According to one embodiment of the present application, at least a portion of the strip magnetic core is located in the inner circle of the second magnetic core.

[0034] According to one embodiment of the present application, the strip magnetic core is distributed on the side of the second magnetic core along the thickness direction of the second magnetic core, the projection of the strip magnetic core and the second magnetic core along the thickness direction of the second magnetic core partially overlap, and the projection of the strip magnetic core and the first magnetic core along the thickness direction of the second magnetic core at least partially overlap.

[0035] In a second aspect, the present application provides an inverter, which includes: any one of the above-mentioned integrated inductors.

[0036] According to the inverter provided in the embodiment of the present application, on the one hand, by providing a first magnetic core and a second magnetic core, and the first magnetic core is wrapped around the outer ring of the second magnetic core, the differential and common mode magnetic circuits can be separated to a certain extent. The first magnetic core mainly provides a common mode component, and the second magnetic core mainly provides a differential mode component. Compared with the related art in which the same magnetic core provides both a common mode component and a differential mode component, the cross-sectional area of ​​the magnetic core is increased, thereby increasing the path of the differential mode magnetic lines of force and the common mode magnetic lines of force, making the first magnetic core and the second magnetic core less likely to saturate, thereby improving the common mode inductance of the first magnetic core and the differential mode inductance of the second magnetic core; on the other hand, by providing a third magnetic core, a closed magnetic path is formed between the third magnetic core and the area on which the winding is wound on the second magnetic core, so that the air path through which the leakage magnetic flux passes becomes shorter. After the air gap in the magnetic circuit is reduced, the air magnetic resistance is reduced, and the differential mode magnetic flux is increased, thereby further improving the inductance value of the integrated inductor.

[0037] In a third aspect, the present application provides a circuit component, wherein the inverter includes: any one of the above-mentioned integrated inductors.

[0038] According to the inverter provided in the embodiment of the present application, on the one hand, by providing a first magnetic core and a second magnetic core, and the first magnetic core is wrapped around the outer ring of the second magnetic core, the differential and common mode magnetic circuits can be separated to a certain extent. The first magnetic core mainly provides a common mode component, and the second magnetic core mainly provides a differential mode component. Compared with the related art in which the same magnetic core provides both a common mode component and a differential mode component, the cross-sectional area of ​​the magnetic core is increased, thereby increasing the path of the differential mode magnetic lines of force and the common mode magnetic lines of force, making the first magnetic core and the second magnetic core less likely to saturate, thereby improving the common mode inductance of the first magnetic core and the differential mode inductance of the second magnetic core; on the other hand, by providing a third magnetic core, a closed magnetic path is formed between the third magnetic core and the area on which the winding is wound on the second magnetic core, so that the air path through which the leakage magnetic flux passes becomes shorter. After the air gap in the magnetic circuit is reduced, the air magnetic resistance is reduced, and the differential mode magnetic flux is increased, thereby further improving the inductance value of the integrated inductor.

[0039] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0041] FIG1 is a schematic diagram of a structure of an integrated inductor provided in an embodiment of the present application;

[0042] FIG2 is a second structural diagram of an integrated inductor provided in an embodiment of the present application;

[0043] FIG3 is a third structural diagram of an integrated inductor provided in an embodiment of the present application;

[0044] FIG4 is a fourth structural diagram of an integrated inductor provided in an embodiment of the present application;

[0045] FIG5 is a schematic diagram of the internal magnetic flux of an integrated inductor provided in an embodiment of the present application;

[0046] FIG6 is a fifth structural diagram of an integrated inductor provided in an embodiment of the present application;

[0047] FIG7 is a sixth structural diagram of an integrated inductor provided in an embodiment of the present application;

[0048] FIG8 is a left side view of the integrated inductor in FIG7;

[0049] FIG9 is a seventh structural diagram of an integrated inductor provided in an embodiment of the present application;

[0050] FIG10 is a left side view of the integrated inductor in FIG9;

[0051] FIG11 is a second schematic diagram of the internal magnetic flux of the integrated inductor provided in an embodiment of the present application;

[0052] FIG12 is a schematic diagram of the internal magnetic flux of a toroidal common-mode inductor in the related art;

[0053] FIG13 is a schematic diagram of the differential-mode equivalent magnetic circuit structure of the integrated inductor provided in an embodiment of the present application.

[0054] Reference numerals: first magnetic core 1 , second magnetic core 2 , third magnetic core 3 , extended arm 31 , arc-shaped magnetic core 32 , winding 4 . DETAILED DESCRIPTION

[0055] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0056] The integrated inductor, circuit assembly, and inverter according to embodiments of the present application are described below with reference to FIG. 1 to FIG. 11 and FIG. 13 .

[0057] It should be understood that the integrated inductor of the present application can be applied to converters, filter circuits, and other circuits, and the present application does not limit this.

[0058] As shown in FIG1 , the integrated inductor according to the embodiment of the present application includes: a first magnetic core 1 , a second magnetic core 2 , a third magnetic core 3 and a plurality of windings 4 .

[0059] The first magnetic core 1 is wrapped around the outer ring of the second magnetic core 2, and the second magnetic core 2 is separated from the first magnetic core 1; each turn of each winding 4 is wound around the first magnetic core 1 and the second magnetic core 2, and any two windings 4 are separated, and a common-mode inductance is formed between the multiple windings 4 and the first magnetic core 1; there is no winding 4 wound on the third magnetic core 3, and a closed magnetic path is formed between the area of ​​the second magnetic core 2 where the winding 4 is wound and the third magnetic core 3, and a differential-mode inductance is formed between each winding 4 and the closed magnetic path.

[0060] Among them, the second magnetic core 2 is arranged in the inner circle of the first magnetic core 1, and there is an air gap between the outer wall of the second magnetic core 2 and the inner wall diameter of the first magnetic core 1. The first magnetic core 1 is mainly used to provide common mode inductance, and the second magnetic core 2 is mainly used to provide differential mode inductance.

[0061] A common-mode inductor is formed between at least two windings 4 and the first magnetic core 1 . As shown in FIG1 , a common-mode inductor is formed between three windings 4 and the first magnetic core 1 .

[0062] The third magnetic core 3 and at least a portion of the second magnetic core 2 form a closed magnetic path. A group of windings 4 is provided in the closed magnetic path. A differential mode inductance is formed between each winding 4 and the closed magnetic path.

[0063] Among them, the third magnetic core 3 can be arranged in the inner ring of the second magnetic core 2; or, the third magnetic core 3 can also be arranged on the side of the second magnetic core 2; or, the third magnetic core 3 can also be arranged on the side of the second magnetic core 2 and the first magnetic core 1; or, the third magnetic core 3 can also be partially arranged in the inner ring of the second magnetic core 2 and partially arranged on the side of the second magnetic core 2; or, the third magnetic core 3 can also be partially arranged in the inner ring of the second magnetic core 2 and partially arranged on the side of the second magnetic core 2 and the first magnetic core 1.

[0064] There is an air gap between any two of the third magnetic core 3, the second magnetic core 2 and the first magnetic core 1, and the air gap can be filled with at least one of an insulating colloid, a solid insulating frame and a solid insulating board to achieve insulation and fixation between any two of the third magnetic core 3, the second magnetic core 2 and the first magnetic core 1.

[0065] The plurality of windings 4 may be two or three. When there are two windings 4, the integrated inductor is a two-phase difference common mode integration. When there are three windings 4, the integrated inductor is a three-phase difference common mode integration.

[0066] In related technologies, many differential and common mode integration solutions have been produced due to the good symmetry and large available space of the annular magnetic core. The principle of the differential and common mode integration solution is to provide a path for the differential mode magnetic lines of force by adding additional magnetic cores. At the same time, due to the air gap, the common mode magnetic lines of force still flow along the original path, thereby increasing the differential mode component without affecting the common mode inductance, thereby achieving the purpose of differential and common mode integration.

[0067] Due to space limitations, the additional magnetic strips are relatively thin, limiting the increase in differential mode inductance. Thicker Y-shaped magnetic strips, while increasing differential mode inductance, can easily lead to local saturation of the core, resulting in a decrease in core permeability and a reduction in common mode inductance, failing to meet design requirements.

[0068] According to the integrated inductor provided in the embodiment of the present application, on the one hand, by providing a first magnetic core 1 and a second magnetic core 2, and the first magnetic core 1 is wrapped around the outer ring of the second magnetic core 2, the differential and common mode magnetic circuits can be separated to a certain extent. The first magnetic core 1 mainly provides a common mode component, and the second magnetic core 2 mainly provides a differential mode component. Compared with the related art in which the same magnetic core provides both a common mode component and a differential mode component, the cross-sectional area of ​​the magnetic core is increased, thereby increasing the path of the differential mode magnetic lines of force and the common mode magnetic lines of force, making the first magnetic core 1 and the second magnetic core 2 less likely to saturate, thereby improving the common mode inductance of the first magnetic core 1 and the differential mode inductance of the second magnetic core 2; on the other hand, by providing a third magnetic core 3, a closed magnetic path is formed between the third magnetic core 3 and the area on the second magnetic core 2 where the winding 4 is wound, so that the air path through which the leakage magnetic flux passes becomes shorter. After the air gap in the magnetic circuit is reduced, the air magnetic resistance is reduced, and the differential mode magnetic flux is increased, thereby further improving the inductance value of the integrated inductor.

[0069] In some embodiments, the third magnetic core 3 includes multiple ends, which extend toward the first magnetic core 1 and the second magnetic core 2, and at least one end is distributed on the side of the winding 4; the area between the ends on both sides of any winding 4 on the second magnetic core 2 forms a closed magnetic path with the third magnetic core 3.

[0070] There are air gaps between the multiple ends and the first magnetic core 1 and the second magnetic core 2, so that the differential mode equivalent magnetic circuit model of the second magnetic core 2 remains unchanged.

[0071] In this embodiment, the extension of the multiple ends can shorten the air path through which the leakage magnetic flux passes, thereby increasing the differential mode inductance of the integrated inductor.

[0072] The extension positions of the multiple ends may be at least one of the following positions:

[0073] First, as shown in FIG. 1 and FIG. 6 , the plurality of end portions are all located in the inner circle of the second magnetic core 2 , and there are air gaps between the plurality of end portions and the inner peripheral wall of the second magnetic core 2 .

[0074] In this position, multiple ends are located in the inner ring of the second magnetic core 2, which can shorten the air path through which the leakage magnetic fluxes ΦAdm, ΦBdm, and ΦCdm pass, increase the magnetic lines of force of the differential mode in the magnetic core, and thus increase the inductance value without increasing the volume of the integrated inductor, thus meeting the requirements of equipment integration.

[0075] Secondly, as shown in Figure 2, the third magnetic core 3 also includes: an extension arm 31; the extension arm 31 is arranged at the end and extends in the direction close to the first magnetic core 1, and the extension arm 31 is distributed on the side of the second magnetic core 2 along the thickness direction of the second magnetic core 2, and the extension arm 31 and the projection of the second magnetic core 2 along the thickness direction of the second magnetic core 2 at least partially overlap.

[0076] The projection of the extended arm 31 on the side surface of the second magnetic core 2 partially overlaps with the side surface of the second magnetic core 2 .

[0077] In this position, the extension arm 31 extends in a direction close to the first magnetic core 1 , which can increase the cross-sectional area of ​​the magnetic circuit to further reduce the air magnetic resistance, thereby further increasing the inductance value.

[0078] The extension arm 31 can be provided on any side surface of the second magnetic core 2 to increase the cross-sectional area of ​​the magnetic circuit; the extension arm 31 can be provided on both side surfaces of the second magnetic core 2 to further increase the cross-sectional area of ​​the magnetic circuit.

[0079] There is an air gap between the extended arm 31 and the second magnetic core 2, so that the differential-mode equivalent magnetic circuit model of the second magnetic core in FIG5 and FIG11 remains unchanged.

[0080] Third, as shown in Figures 3 and 7, the third magnetic core 3 also includes: an extension arm 31; the extension arm 31 is arranged at the end and extends in the direction close to the outer wall of the first magnetic core 1, and the extension arm 31 is distributed on the side surfaces of the second magnetic core 2 and the first magnetic core 1 along the thickness direction of the second magnetic core 2, and the extension arm 31 partially overlaps with the projection of the second magnetic core 2 along the thickness direction of the second magnetic core 2, and the extension arm 31 at least partially overlaps with the projection of the first magnetic core 1 along the thickness direction of the second magnetic core 2.

[0081] The projections of the extended arms 31 on the side surfaces of the second magnetic core 2 and the first magnetic core 1 partially overlap with the side surfaces of the second magnetic core 2 and the first magnetic core 1 .

[0082] It should be noted that the first magnetic core 1 has a small number of magnetic lines of force in the differential mode, a low magnetic flux density, and a low utilization rate. In this embodiment, the extension arm 31 is lengthened so that it covers at least part of the first magnetic core 1 to construct a differential mode magnetic line path with a smaller air magnetic resistance, thereby increasing the inductance value of the first magnetic core 1 and improving the utilization rate of the first magnetic core 1.

[0083] In this embodiment, the differential mode inductance of the first magnetic core 1 can be controlled by adjusting the overlapping area between the extension arm 31 and the projection of the first magnetic core 1 along the thickness direction of the second magnetic core 2 .

[0084] In the process of increasing the differential mode inductance of the first magnetic core 1, it is necessary to control the magnetic flux density of the first magnetic core 1 not to exceed the saturation magnetic flux density of the first magnetic core 1, so as to ensure the common mode inductance of the first magnetic core 1, while fully utilizing the first magnetic core 1 and improving the overall power density.

[0085] Among them, the extension arm 31 can be set on any side of the second magnetic core 2 and the first magnetic core 1 to increase the magnetic circuit cross-sectional area; the extension arm 31 can be set on both sides of the second magnetic core 2 and the first magnetic core 1 to further increase the magnetic circuit cross-sectional area.

[0086] There are air gaps between the extended arm 31 and the second magnetic core 2 and the first magnetic core 1, so that the differential-mode equivalent magnetic circuit models of the second magnetic core in FIG. 5 and FIG. 11 remain unchanged.

[0087] In some embodiments, as shown in Figures 8 and 10, along the thickness direction of the first magnetic core 1, the height of the third magnetic core 3 is less than or equal to the height of the winding 4, thereby further increasing the inductance value of the second magnetic core 2 without increasing the volume of the integrated inductor, thereby improving the power density.

[0088] In some embodiments, each winding 4 in the plurality of windings 4 has the same number of turns, and each winding 4 in the plurality of windings 4 has the same winding direction.

[0089] In some embodiments, the first magnetic core 1 and the second magnetic core 2 are both closed ring-shaped, and the outer circumferential wall of the second magnetic core 2 is spaced equidistant from the inner circumferential wall of the first magnetic core 1 .

[0090] The shapes of the first magnetic core 1 and the second magnetic core 2 can be set according to the use scenario of the integrated inductor, for example, they can be any one of a circular ring, an elliptical ring, a rectangular ring, an oblong or an irregular shape.

[0091] The shape of the third magnetic core 3 can be set according to the shapes of the first magnetic core 1 and the second magnetic core 2 , so as to achieve the effect of increasing the inductance value without affecting the overall volume of the integrated inductor.

[0092] In some embodiments, as shown in Figures 1 to 4, the first magnetic core 1 and the second magnetic core 2 are both closed circular rings, and multiple windings 4 are distributed at intervals along the circumference of the circular ring; each end of the third magnetic core 3 is located between two adjacent windings 4, and the area on the second magnetic core 2 where any winding 4 is wound forms a closed magnetic path with the corresponding area of ​​the third magnetic core 3, wherein the corresponding area of ​​the third magnetic core 3 is the area between the two ends on both sides of the winding 4.

[0093] In this embodiment, the first magnetic core 1 and the second magnetic core 2 are concentric rings.

[0094] The third magnetic core 3 may have at least one of the following structural forms:

[0095] First, as shown in Figures 1 and 3, the windings 4 include three; the third magnetic core 3 includes three segments distributed along the circumferential direction, the radial inner ends of the three segments are connected at the same position, and the radial outer ends of the three segments are located between two adjacent windings 4; the area on the second magnetic core 2 where any winding 4 is wound forms a closed magnetic path with the two segments of the three segments located on both sides of the winding 4.

[0096] In this embodiment, the third magnetic core 3 is Y-shaped, and the radial inner ends of the three sections of the third magnetic core 3 can be connected at the center of the first magnetic core 1 or at other positions.

[0097] As shown in FIG. 1 , the three core segments of the third magnetic core 3 are located in the inner circle of the second magnetic core 2 , and the radial outer ends of the three core segments of the third magnetic core 3 may be spaced apart from the inner circumferential wall of the second magnetic core 2 .

[0098] As shown in FIG3 , radially outer ends of the three magnetic core sections of the third magnetic core 3 may be provided with extension arms 31 , and the extension arms 31 may extend to the first magnetic core 1 or the second magnetic core 2 .

[0099] Secondly, as shown in Figure 4, the third magnetic core 3 includes multiple arc-shaped magnetic cores 32, and each arc-shaped magnetic core 32 includes two ends; the two ends of the arc-shaped magnetic core 32 are respectively located on both sides of the winding 4, and the area on the second magnetic core 2 where the winding 4 is wound forms a closed magnetic path with the arc-shaped magnetic core 32.

[0100] In this embodiment, any two of the plurality of arc-shaped magnetic cores 32 may or may not contact each other, and this application does not impose any limitation thereto. When any two of the plurality of arc-shaped magnetic cores 32 contact each other, the volume of the integrated inductor structure can be relatively reduced.

[0101] The shape of the arc-shaped magnetic core 32 may be a circular arc or an elliptical arc. As shown in FIG. 4 , the shape of the arc-shaped magnetic core 32 is a semicircular arc.

[0102] By configuring the third magnetic core 3 to be in an arc shape, the difficulty of processing and assembling can be reduced.

[0103] In this embodiment, considering the installation space of the integrated inductor, the plurality of arc-shaped magnetic cores 32 can be located in the inner circle of the second magnetic core 2 or on the sides of the second magnetic core 2 and the first magnetic core 1 .

[0104] In some embodiments, multiple arc-shaped magnetic cores 32 can be located on one side of the second magnetic core 2 to increase the magnetic circuit cross-sectional area, or multiple arc-shaped magnetic cores 32 can be located on both sides of the second magnetic core 2 to further increase the magnetic circuit cross-sectional area, thereby increasing the inductance value.

[0105] As shown in FIG6 to FIG11 , the racetrack-type inductor can also achieve the same technical indicators as the toroidal inductor.

[0106] In some embodiments, as shown in Figures 6, 7 and 9, the first magnetic core 1 and the second magnetic core 2 each include a first side and a second side that are oppositely arranged, the first side and the second side are enclosed into a closed shape, and a plurality of windings 4 are wound on one of the first sides; the third magnetic core 3 includes a plurality of bar magnetic cores that are spaced apart, the bar magnetic cores extend toward the two first sides, and are located between two adjacent windings 4; the bar magnetic core and the adjacent second side, and the area on the first side between the second side and the bar magnetic core form a closed magnetic path; the two adjacent bar magnetic cores and the area on the first side between the two bar magnetic cores form a closed magnetic path.

[0107] In this embodiment, the first magnetic core 1 and the second magnetic core 2 may be in a racetrack shape or a rectangular shape.

[0108] The third magnetic core 3 may have at least one of the following structural forms:

[0109] First, as shown in FIG6 and FIG7 , at least a portion of the strip-shaped magnetic core is located in the inner circle of the second magnetic core 2 .

[0110] In this embodiment, as shown in FIG6 , the strip core is located in the inner circle of the second magnetic core 2 , and both ends of the strip core extend toward the inner circumferential wall of the second magnetic core 2 and are spaced apart from the inner circumferential wall of the second magnetic core 2 .

[0111] In this embodiment, as shown in FIG7 , an extension arm 31 is provided at the end of the strip-shaped magnetic core. The extension arm 31 may extend to the first magnetic core 1 or the second magnetic core 2 .

[0112] Secondly, as shown in Figures 9 and 10, the strip magnetic cores are distributed on the side surfaces of the second magnetic core 2 along the thickness direction of the second magnetic core 2, the projections of the strip magnetic cores and the second magnetic core 2 along the thickness direction of the second magnetic core 2 partially overlap, and the projections of the strip magnetic cores and the first magnetic core 1 along the thickness direction of the second magnetic core 2 at least partially overlap.

[0113] Among them, considering the installation space of the integrated inductor, multiple bar magnetic cores can be located on one side of the second magnetic core 2 to increase the cross-sectional area of ​​the magnetic circuit, or multiple bar magnetic cores can be located on both sides of the second magnetic core 2 to further increase the cross-sectional area of ​​the magnetic circuit, thereby increasing the inductance value.

[0114] In related technologies, the common-mode fluxes ΦAcm, ΦBcm, and ΦCcm of a three-phase toroidal common-mode inductor cancel each other out in the core due to their 120° phase shift. The magnitude of the leakage flux, or differential-mode fluxes ΦAdm, ΦBdm, and ΦCdm, determines the magnitude of the common-mode inductor's differential-mode component and the core's saturation level. When determining the common-mode inductance, its current excitation and number of turns are often also determined.

[0115] The calculation formula for differential and common mode integrated inductors is: L=NΦ / I

[0116] Where L is the differential common-mode integrated inductor, N is the number of turns, Φ is the magnetic flux contained in the winding, and I is the current excitation.

[0117] It should be noted that the leakage flux path of the three-phase toroidal inductor in FIG12 includes the path of the magnetic flux on the two-dimensional plane, and also includes the leakage flux in all directions around the winding. These leakage fluxes jointly determine the differential mode inductance.

[0118] As shown in Figure 13, R0 represents the air reluctance, Rdm represents the core reluctance, and FAdm represents the magnetomotive force generated by the phase A winding. The differential-mode flux ΦAdm is calculated by dividing the magnetomotive force by the reluctance. The magnetomotive force is determined by the number of turns N and the excitation current I and is a constant when designing the differential-mode inductance.

[0119] The formula for calculating the magnetic resistance between air and magnetic core is: R=le / (μ0*Ae)

[0120] Among them, R is the magnetic resistance, le is the magnetic path length, μ0 is the relative magnetic permeability, and Ae is the magnetic path cross-sectional area.

[0121] Because the relative magnetic permeability of air is 1, while the magnetic core permeability is generally in the thousands to tens of thousands, the difference in magnetic path length and cross-sectional area between the two is negligible. Therefore, R0>>Rdm, meaning that the differential-mode flux is primarily determined by the reluctance of air. Figure 13 shows that in a toroidal core, the leakage flux has a longer path through the air, resulting in a higher reluctance of air, which results in a smaller differential-mode flux and, consequently, a smaller differential-mode component in the toroidal common-mode inductor.

[0122] The internal magnetic flux of the integrated common-mode inductor after integration of the integrated inductor provided in the embodiment of the present application is shown in Figures 5 and 11. A third magnetic core 3 is added to the inner ring of the second magnetic core 2 to shorten the air path through which the leakage magnetic fluxes ΦAdm, ΦBdm, and ΦCdm pass. It can be seen from the calculation formula of the differential common-mode integrated inductor that after the air gap le in the magnetic circuit is reduced, the air magnetic resistance R0 is reduced, and the differential-mode magnetic flux ΦAdm is increased, which increases the differential-mode component Lidm of the common-mode inductor.

[0123] The calculation formula of magnetic flux density is: B=Φ / S

[0124] Where B is the magnetic flux density, S is the cross-sectional area of ​​the core, and Φ is the magnetic flux contained in the winding.

[0125] However, as the differential-mode component increases, the calculation formula for magnetic flux density indicates that, due to the increase in differential-mode flux, the magnetic flux density of the second magnetic core 2 increases while the core cross-sectional area remains unchanged. This may cause the second magnetic core 2 to partially saturate. Magnetic core saturation causes the core's magnetic permeability to decrease. However, because the core's magnetic permeability is much greater than the air's, even after the core reaches a certain degree of saturation, R0>>Rdm remains. Therefore, the reduction in the differential-mode component of the inductance is minimal and can be ignored. This significantly reduces the common-mode inductance Licm provided by the second magnetic core 2. In this case, the second magnetic core 2 primarily provides the differential-mode component, with a relatively small common-mode component.

[0126] In first magnetic core 1, common-mode magnetic fluxes ΦAcm, ΦBcm, and ΦCcm still cancel each other out, while the differential-mode magnetic flux remains small due to the air gap between first magnetic core 1 and second magnetic core 2. Consequently, the differential-mode inductance Lodm provided by first magnetic core 1 is relatively small. Therefore, first magnetic core 1 primarily provides its common-mode inductance Locm. Furthermore, due to the small differential-mode magnetic flux in first magnetic core 1, first magnetic core 1 is less susceptible to saturation, ensuring a stable common-mode inductance.

[0127] Through analysis, the total mode inductance and differential mode inductance of this application can be expressed by the following formula:

[0128] Wherein, Lcm is the total common mode inductance, Locm is the common mode inductance of the first magnetic core 1 , Licm is the common mode inductance of the second magnetic core 2 , Ldm is the total differential mode inductance, Lodm is the differential mode inductance of the first magnetic core 1 , and Lidm is the differential mode inductance of the second magnetic core 2 .

[0129] When the second core 2 is fully utilized, that is, when the second core 2 is highly saturated, Locm>>Licm, and Lidm>>Lodm. In other words, the common-mode inductance is mainly provided by the first core 1, and the differential-mode inductance is mainly provided by the second core 2.

[0130] When the projections of the third magnetic core 3 and the first magnetic core 1 along the thickness direction of the second magnetic core 2 at least partially overlap, the magnetic path cross-sectional area used in calculating the air gap magnetic resistance is the partial area of ​​the overlap between the third magnetic core 3 and the first magnetic core 1 .

[0131] In a second aspect, the present application further provides a circuit component comprising any one of the above-mentioned integrated inductors.

[0132] The circuit assembly includes a circuit board and an integrated inductor, and the integrated inductor is connected to the circuit board.

[0133] The circuit board includes an inductor mounting area, a soldering pad is provided in the inductor mounting area, and the integrated inductor is soldered to the soldering pad via wiring pins.

[0134] According to the circuit assembly provided in the embodiment of the present application, on the one hand, by providing a first magnetic core 1 and a second magnetic core 2, and the first magnetic core 1 is wrapped around the outer ring of the second magnetic core 2, the differential and common mode magnetic circuits can be separated to a certain extent. The first magnetic core 1 mainly provides a common mode component, and the second magnetic core 2 mainly provides a differential mode component. Compared with the related art in which the same magnetic core provides both a common mode component and a differential mode component, the cross-sectional area of ​​the magnetic core is increased, thereby increasing the path of the differential mode magnetic lines of force and the common mode magnetic lines of force, making the first magnetic core 1 and the second magnetic core 2 less likely to saturate, thereby improving the common mode inductance of the first magnetic core 1 and the differential mode inductance of the second magnetic core 2; on the other hand, by providing a third magnetic core 3, a closed magnetic path is formed between the third magnetic core 3 and the area on the second magnetic core 2 where the winding 4 is wound, so that the air path through which the leakage magnetic flux passes becomes shorter. After the air gap in the magnetic circuit is reduced, the air magnetic resistance is reduced, and the differential mode magnetic flux is increased, thereby further improving the inductance value of the integrated inductor.

[0135] In a third aspect, the present application further provides an inverter comprising any one of the above-mentioned integrated inductors.

[0136] The inverter includes a housing and a circuit board assembly, the circuit board assembly is connected to the integrated inductor, and the housing surrounds the circuit board assembly.

[0137] According to the inverter provided in the embodiment of the present application, on the one hand, by providing a first magnetic core 1 and a second magnetic core 2, and the first magnetic core 1 is wrapped around the outer ring of the second magnetic core 2, the differential and common mode magnetic circuits can be separated to a certain extent. The first magnetic core 1 mainly provides a common mode component, and the second magnetic core 2 mainly provides a differential mode component. Compared with the related art in which the same magnetic core provides both a common mode component and a differential mode component, the cross-sectional area of ​​the magnetic core is increased, thereby increasing the path of the differential mode magnetic lines of force and the common mode magnetic lines of force, making the first magnetic core 1 and the second magnetic core 2 less likely to saturate, thereby improving the common mode inductance of the first magnetic core 1 and the differential mode inductance of the second magnetic core 2; on the other hand, by providing a third magnetic core 3, a closed magnetic path is formed between the third magnetic core 3 and the area on the second magnetic core 2 where the winding 4 is wound, so that the air path through which the leakage magnetic flux passes becomes shorter. After the air gap in the magnetic circuit is reduced, the air magnetic resistance is reduced, and the differential mode magnetic flux is increased, thereby further improving the inductance value of the integrated inductor.

[0138] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects; for example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0139] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0140] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0141] In the description of this application, “plurality” means two or more.

[0142] In the description of the present application, a first feature being “on” or “under” a second feature may include the first and second features being in direct contact with each other, or the first and second features being in contact with each other not directly but via another feature therebetween.

[0143] In the description of this application, a first feature “on”, “above” and “above” a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0144] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0145] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. An integrated inductor, characterized in that: include: a first magnetic core; A second magnetic core, wherein the first magnetic core surrounds an outer ring of the second magnetic core, and the second magnetic core is spaced apart from the first magnetic core; A plurality of windings, each turn of each winding is wound around the first magnetic core and the second magnetic core, and any two windings are spaced apart, so that a common mode inductor is formed between the plurality of windings and the first magnetic core; A third magnetic core, on which no winding is wound, a closed magnetic path is formed between the area on the second magnetic core on which the winding is wound and the third magnetic core, and a differential mode inductance is formed between each of the windings and the closed magnetic path.

2. The integrated inductor according to claim 1, characterized in that: The third magnetic core comprises a plurality of ends, the plurality of ends extend toward the first magnetic core and the second magnetic core, and at least one of the ends is distributed on a side surface of the winding; The area of ​​the second magnetic core between the ends on both sides of any one of the windings forms a closed magnetic path with the third magnetic core.

3. The integrated inductor according to claim 2, characterized in that: The multiple end portions are all located in the inner circle of the second magnetic core, and there are air gaps between the multiple end portions and the inner peripheral wall of the second magnetic core.

4. The integrated inductor according to claim 3, characterized in that: The third magnetic core further includes: an extended arm; The extension arm is arranged at the end and extends in a direction close to the first magnetic core. The extension arm is distributed on the side of the second magnetic core along the thickness direction of the second magnetic core. The extension arm at least partially overlaps with the projection of the second magnetic core along the thickness direction of the second magnetic core.

5. The integrated inductor according to claim 3, characterized in that: The third magnetic core further includes: an extended arm; The extension arm is arranged at the end portion and extends in a direction close to the outer peripheral wall of the first magnetic core. The extension arm is distributed on the sides of the second magnetic core and the first magnetic core along the thickness direction of the second magnetic core. The extension arm partially overlaps with the projection of the second magnetic core along the thickness direction of the second magnetic core, and the extension arm at least partially overlaps with the projection of the first magnetic core along the thickness direction of the second magnetic core.

6. The integrated inductor according to any one of claims 1 to 5, characterized in that: The number of coil turns of each of the plurality of windings is the same, and the winding direction of each of the plurality of windings is the same.

7. The integrated inductor according to any one of claims 1 to 6, characterized in that: The first magnetic core and the second magnetic core are both closed ring-shaped, and the outer circumferential wall of the second magnetic core is spaced equidistant from the inner circumferential wall of the first magnetic core.

8. The integrated inductor according to any one of claims 1 to 6, characterized in that: Along the thickness direction of the first magnetic core, the height of the third magnetic core is less than or equal to the height of the winding.

9. The integrated inductor according to any one of claims 1 to 8, characterized in that: The first magnetic core and the second magnetic core are both in a closed annular shape, and the plurality of windings are spaced and distributed along the circumference of the annular shape; Each of the ends of the third magnetic core is located between two adjacent windings, and the area on the second magnetic core where any of the windings are wound forms a closed magnetic path with the corresponding area of ​​the third magnetic core, wherein the corresponding area of ​​the third magnetic core is the area between the two ends on both sides of the winding.

10. The integrated inductor according to claim 9, characterized in that: The windings include three; The third magnetic core includes three sections distributed along the circumferential direction, the radial inner ends of the three sections are connected at the same position, and the radial outer ends of the three sections are located between two adjacent windings; The area on the second magnetic core where any of the windings are wound forms a closed magnetic path with two of the three sections located on both sides of the winding.

11. The integrated inductor according to claim 9, characterized in that: The third magnetic core includes a plurality of arc-shaped magnetic cores, each of which includes two ends; The two ends of the arc-shaped magnetic core are respectively located at two sides of the winding, and the area of ​​the second magnetic core where the winding is wound forms a closed magnetic path with the arc-shaped magnetic core.

12. The integrated inductor according to any one of claims 1 to 8, characterized in that: The first magnetic core and the second magnetic core each include a first side and a second side that are oppositely disposed, the first side and the second side are enclosed to form a closed shape, and the plurality of windings are wound on one of the first sides; The third magnetic core includes a plurality of strip-shaped magnetic cores arranged at intervals, the strip-shaped magnetic cores extend toward the two first sides and are located between two adjacent windings; The strip magnetic core and the adjacent second side and the area between the second side and the strip magnetic core on the first side form a closed magnetic path; the adjacent two strip magnetic cores and the area between the two strip magnetic cores on the first side form a closed magnetic path.

13. The integrated inductor according to claim 12, characterized in that: At least a portion of the strip-shaped magnetic core is located in the inner circle of the second magnetic core.

14. The integrated inductor according to claim 12, characterized in that: The strip magnetic core is distributed on the side of the second magnetic core along the thickness direction of the second magnetic core. The projections of the second magnetic core along the thickness direction of the second magnetic core partially overlap, and the projections of the strip magnetic core and the first magnetic core along the thickness direction of the second magnetic core at least partially overlap.

15. A circuit assembly, characterized in that: An integrated inductor comprising any one of claims 1-14.

16. An inverter, characterized in that: An integrated inductor comprising any one of claims 1-14.

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