Differential mode and common mode integrated inductor

Abstract

The utility model discloses a differential mode and common mode integrated inductor which comprises two E-shaped magnetic cores (1), a left coil (4) and a right coil (5). Openings of the two E-shaped magnetic cores (1) are consistent, and side columns (3) on the two sides of each E-shaped magnetic core (1) are in butt joint to form a whole. The length of the middle columns (2) of the two E-shaped magnetic cores (1) is smaller than that of the side columns (3) on the two sides, and a middle column air gap (6) is formed after the side columns (3) are in butt joint. A left wire outlet head (8) of the left coil (4) is fixed in a left wire outlet hole (9) in the bottom insulating plate (7), and a right wire outlet head (10) of the right coil (5) is fixed in a right wire outlet hole (11) in the bottom insulating plate (7); the middle column sections (13) of the two E-shaped magnetic cores (1) are in a symmetrical concave special shape, and the side column sections (14) and the side face sections (12) of the two E-shaped magnetic cores (1) are oval. According to the differential-mode and common-mode magnetic integrated inductor, the size of an electromagnetic component is reduced, and the provided differential-mode and common-mode magnetic integrated inductor has the advantages of being small in magnetic core and coil material consumption, good in heat dissipation, large in common-mode inductance value, adjustable in differential-mode inductance value, excellent in anti-saturation capacity and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of magnetic element integration, in particular to a differential common mode integrated inductor. Background Art

[0002] In the prior art, a common-mode inductor and a differential-mode inductor are generally required to filter out unwanted signals. In order to meet the EMC requirements of power electronic equipment, an input filter is generally required to improve the EMI performance of power electronic equipment. Because the two inductors are independent of each other and have single functions, they have the disadvantages of large space occupation and high total cost, which makes it difficult to meet the needs of high efficiency, high density and high reliability development of future power electronic equipment.

[0003] Based on the above situation, common-differential mode magnetic integrated inductors are gradually becoming one of the future development trends. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a differential common mode integrated inductor which meets the safety requirements of full voltage range input with a relatively small volume and has the characteristics of simple manufacturing process and good heat dissipation.

[0005] The utility model adopts the following technical solutions:

[0006] A differential common mode integrated inductor, characterized in that it comprises two E-type magnetic cores (1) and a left coil (4) and a right coil (5), the two E-type magnetic cores are divided into a center column (2) and two side columns (3), the openings of the two E-type magnetic cores (1) are arranged in a consistent manner, and the side columns (3) on both sides of the two E-type magnetic cores (1) are butt-jointed to form an integrated whole.

[0007] A left coil (4) and a right coil (5) are respectively mounted on the side columns (3) on both sides of the two E-shaped magnetic cores (1) after docking; the length of the middle column (2) of the two E-shaped magnetic cores (1) is smaller than the length of the side columns (3) on both sides, and a middle column air gap (6) is formed after the side columns (3) are docked.

[0008] Furthermore, the differential common mode integrated inductor does not include a frame, the left coil (4) and the right coil (5) are not wound around the frame, and the coils adopt a flat wire vertical winding structure.

[0009] Furthermore, an epoxy resin layer is coated on the surface of the magnetic core of the left coil (4) and the right coil (5).

[0010] Furthermore, the length of the air gap along the center column (2) is 0.2-14.0 mm.

[0011] Furthermore, the length of the air gap along the center column (2) is 7.0 mm.

[0012] Furthermore, the left coil (4) and the right coil (5) have the same number of turns and are mounted on symmetrical positions of the left and right side columns (3).

[0013] Furthermore, the same-named ends of the left coil (4) and the right coil (5) are located at the same end of the side columns (3) on both sides.

[0014] Furthermore, the left coil (4) and the right coil (5) may be one of a flat copper wire and a flat aluminum wire.

[0015] Furthermore, the left coil (4) and the right coil (5) are wound in opposite directions.

[0016] Furthermore, the middle column cross section (13) is symmetrically concave in shape to increase the winding space, and the side column cross section (14) and the side cross section (12) are both elliptical.

[0017] Furthermore, the differential common mode integrated inductor is characterized in that it also includes a bottom insulating plate (7) located on the left coil (4) and the right coil (5), and the bottom insulating plate (7) is provided with a left outlet hole (9) for the left outlet head (8) of the left coil (4) and a right outlet hole (11) for the right outlet head (10) of the right coil (5) for installation and fixation.

[0018] Furthermore, the two E-shaped magnetic cores (1) are made of high magnetic permeability soft magnetic material.

[0019] Compared with the prior art, the beneficial effects of the utility model are:

[0020] The coated core set hollow coil is used to replace the traditional skeleton, winding and core mode, and the common-differential mode magnetic integrated inductor with mirror-processed core is used to keep the common-mode magnetic circuit high permeability and easy to obtain a large common-mode inductance value, and the differential-mode magnetic circuit maintains low permeability and high anti-saturation ability to prevent the core saturation caused by the DC bias of the differential-mode circuit. It can not only meet the safety requirements of the full voltage range input, but also has the characteristics of adjustable differential-mode inductance value of the common-differential mode inductor, less core and coil materials, simple manufacturing process and good heat dissipation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a three-dimensional schematic diagram of the magnetic core structure of a differential common mode integrated inductor according to an embodiment of the utility model.

[0022] Figure 2 It is a three-dimensional front view of the overall appearance of a differential and common mode integrated inductor according to an embodiment of the utility model.

[0023] Figure 3 It is a three-dimensional bottom view of the overall appearance of a differential and common mode integrated inductor according to an embodiment of the utility model.

[0024] Figure 4 It is a front view of an E-shaped magnetic core (1) of a differential common mode integrated inductor according to an embodiment of the utility model.

[0025] Figure 5 This is a working principle diagram of a differential common mode integrated inductor plus a common mode signal with opposite polarity and the same amplitude in an embodiment of the utility model.

[0026] Figure 6 This is a working principle diagram of a differential-common-mode integrated inductor plus a differential-mode signal with opposite polarity and the same amplitude in an embodiment of the utility model.

[0027] Reference numerals:

[0028] 1- E-type core, 2- middle column, 3- side column, 4- left coil, 5- right coil, 6- middle column air gap, 7- bottom insulating plate, 8- left outlet, 9- left outlet, 10- left outlet, 11- left outlet, 12- side section, 13- middle column section, 14- side column section. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model so that those skilled in the art can implement the utility model.

[0030] In addition, the directional terms used in the present invention described below, such as left, right, center, edge, side, bottom, etc., are only reference directions in the accompanying drawings, and the technical features involved in each implementation method can be combined with each other as long as there is no conflict between them.

[0031] like Figure 1 As shown, the utility model provides a differential common mode integrated inductor, comprising two E-shaped magnetic cores (1), each E-shaped magnetic core (1) comprising a middle column (2) and two side columns (3); the openings of the two E-shaped magnetic cores (1) are arranged in a consistent manner, and the side columns (3) on both sides of the two E-shaped magnetic cores (1) are butt-jointed to form an integrated whole.

[0032] like Figure 2 As shown, the utility model provides a differential common mode integrated inductor, wherein a left coil (4) and a right coil (5) are respectively mounted on the side columns (3) on both sides of the two E-type magnetic cores (1) after being connected; the length of the middle column of the two E-type magnetic cores (1) is smaller than the length of the side columns (3) on both sides, and a middle column air gap (6) is formed after the side columns are connected.

[0033] The contact surface of the side column (3) is mirror-finished, and based on the mirror-finishing of the contact surface of the side column (3), the common mode inductance value can be further increased. In terms of material, the two E-type magnetic cores (1) are made of high magnetic permeability soft magnetic material.

[0034] In a preferred embodiment, the side pillars (3) on both sides of the contact surface of the side pillars (3) of the left coil (4) and the right coil (5) are coated with an epoxy resin layer, and the thickness of the epoxy resin layer is preferably 0.2-0.4 mm. The core is coated with an epoxy resin layer so that it can meet the safety requirements of full voltage input, and an insulating paper tube or a plastic tube can also be added to strengthen the insulation.

[0035] In this embodiment, the left coil (4) and the right coil (5) have the same number of turns and are mounted on symmetrical positions of the side columns (3) on both sides. The left coil (4) and the right coil (5) are flat copper wires, and the same-named ends of the left coil (4) and the right coil (5) are located at the same end of the side columns (3) on both sides.

[0036] like Figure 3 As shown, the bottom insulating plate (7) is provided with a left outlet hole (9) for the left outlet head (8) of the left coil (4) and a right outlet hole (11) for the right outlet head (10) of the right coil (5). In this example, after the two E-type magnetic cores (1) and the left coil (4) and the right coil (5) are assembled, epoxy glue is applied to fix them to prevent them from loosening.

[0037] like Figure 4 As shown, the middle column cross section (13) is symmetrically concave to increase the winding space, and the side column cross section (14) and the side cross section (12) are both elliptical.

[0038] When assembling the product, the wound left coil (4) and right coil (5) are assembled onto the side columns (3) on both sides of the butted E-shaped magnetic core (1), and the middle column (2) of the magnetic core forms a middle column air gap (6), so that different differential mode inductance values ​​can be obtained.

[0039] like Figure 5 As shown, according to the principles of electricity and magnetism, when a common-mode signal with the same polarity and amplitude is added, the magnetic resistance of the middle column (2) increases due to the middle column air gap (6) opened in the middle column (2), so most of the magnetic flux passes through the side column (3) of the magnetic core. According to the right-hand screw rule, a magnetic flux Φc of the same phase will be generated, and the total magnetic flux will be twice the magnetic flux of a single coil, so a high common-mode impedance will be presented.

[0040] like Figure 6As shown, when a differential mode signal with opposite polarity and the same amplitude is added, according to the right-hand screw rule, an anti-phase magnetic flux Φd will be generated, and the two sides will be superimposed together through the middle column. Since the middle column increases the air gap, most of the magnetic pressure drop is in the air gap. By changing the size of the air gap, both the differential mode inductance size and the DC superposition characteristics (i.e., the ability to withstand bias current) can be changed. In a preferred embodiment, the length of the air gap along the direction of the middle column (2) is adjustable from 0.2 to 14.0 mm. For example, in this embodiment, the length of the middle column air gap (6) along the direction of the middle column (2) is designed to be 7.0 mm. The air gap length can be appropriately adjusted according to actual application requirements.

[0041] The common-differential-mode magnetic integrated inductor realizes the magnetic integration of common-mode inductor and differential-mode inductor, and at the same time, the common-mode magnetic circuit maintains high magnetic permeability and is easy to obtain a large common-mode inductance value, and the differential-mode magnetic circuit maintains low magnetic permeability and high anti-saturation capability to prevent the saturation of the magnetic core caused by the DC bias of the differential-mode loop. Compared with the traditional solution of using two inductors (common-mode inductor and differential-mode inductor) to suppress common-mode interference and differential-mode interference respectively, the overall volume of the inductor of this embodiment is smaller, which can not only meet the safety requirements of full voltage range input, but also has the characteristics of adjustable differential-mode inductance value of common-differential-mode inductor, less material for magnetic core and coil, simple manufacturing process and good heat dissipation.

[0042] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments, and the above embodiments and descriptions only describe the principles of the utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A differential common mode integrated inductor, characterized in that: The invention comprises two E-shaped magnetic cores (1) and a left coil (4) and a right coil (5); the openings of the two E-shaped magnetic cores (1) are arranged uniformly, and the side columns (3) on both sides of the E-shaped magnetic cores (1) are butt-jointed to form an integral whole; the length of the middle column (2) of the two E-shaped magnetic cores (1) is less than the length of the side columns (3) on both sides, and a middle column air gap (6) is formed after the side columns (3) are butt-jointed; the left outlet head (8) of the left coil (4) is fixed in the left outlet hole (9) on the bottom insulating plate (7), and the right outlet head (10) of the right coil (5) is fixed in the right outlet hole (11) on the bottom insulating plate (7); the middle column cross section (13) of the two E-shaped magnetic cores (1) is a symmetrical concave special shape, and the side column cross section (14) and the side cross section (12) are both elliptical.

2. The differential and common mode integrated inductor according to claim 1, characterized in that: The differential common mode integrated inductor does not include a frame, and the coil adopts a flat wire vertical winding structure; an epoxy resin layer is coated on the surface of the magnetic core of the left coil (4) and the right coil (5), and the thickness of the epoxy resin layer is 0.2-0.4 mm.

3. The differential and common mode integrated inductor according to claim 1, characterized in that: The length of the middle column air gap (6) is 0.2-14 mm.

4. The differential and common mode integrated inductor according to claim 1, characterized in that: The left coil (4) and the right coil (5) have the same number of turns, and the left coil (4) and the right coil (5) are sleeved on symmetrical positions of the side columns (3) on the left and right sides.

5. The differential common mode integrated inductor according to claim 1, characterized in that: The left coil (4) and the right coil (5) may be one of a flat copper wire and a flat aluminum wire.

6. The differential and common mode integrated inductor according to claim 1, characterized in that: The same-named ends of the left coil (4) and the right coil (5) are located at the same end of the side columns (3) on both sides, and the left coil (4) and the right coil (5) are wound in opposite directions.

7. The differential and common mode integrated inductor according to claim 1, characterized in that: The middle column cross section (13) is symmetrically concave to increase the winding space, and the side column cross section (14) and the side cross section (12) are both elliptical.

8. The differential common mode integrated inductor according to claim 1, characterized in that: The bottom insulating plate (7) is provided with a left wire outlet hole (9) for the left wire outlet head (8) of the left coil (4) and a right wire outlet hole (11) for the right wire outlet head (10) of the right coil (5) for installation and fixation.

9. The differential common mode integrated inductor according to claim 1, characterized in that: The two E-shaped magnetic cores are made of high magnetic permeability soft magnetic material.

Images