Integrated inductor and integrated circuit

Abstract

The present invention discloses an integrated inductor and integrated circuit, wherein the integrated inductor includes a magnetic core and windings, the magnetic core including a core center leg, a first side leg, a second side leg, an upper magnetic core base plate, and a lower magnetic core base plate; the windings include a first inductor winding wound on the first side leg, and a second inductor winding wound on the second side leg; the direction of the magnetic flux generated by the first inductor winding is opposite to the direction of the magnetic flux generated by the second inductor winding; the magnetic flux density generated by the first inductor winding is different from the magnetic flux density generated by the second inductor winding; and air gaps are provided on both the first side leg and the second side leg, with the air gaps of the first side leg and the second side leg being different. The present invention achieves flexible adjustment based on the actual proportion of copper loss and iron loss, thereby reducing the volume of the magnetic core, reducing magnetic core loss, and improving circuit efficiency. At the same time, the present invention also adopts differentiated design based on heat dissipation and efficiency considerations, and compromises magnetic loss and copper loss, so that the magnetic element coil and magnetic core can be maximized.

Description

Technical Field

[0001] The present invention relates to the field of circuit design, and in particular to an integrated inductor and an integrated circuit. Background Art

[0002] With the advancement of power semiconductor technology, high efficiency, high power density, and compact size are the driving forces of modern power electronics. This has prompted researchers to push switching frequencies higher. However, increasing switching frequencies inevitably introduces a series of challenges, such as reduced core utilization, increased core losses, and lower efficiency. Power inductors and transformers are crucial components of power electronics converters. As magnetic component technology matures, achieving integration, miniaturization, high efficiency, and high utilization while also ensuring heat dissipation has become a hot topic for many researchers. Summary of the Invention

[0003] One of the objectives of the embodiments of the present invention is to provide an integrated inductor, which is used to solve the problems of low magnetic core utilization and low efficiency in the prior art, and at the same time solve the problem of actual inductor heat dissipation differences.

[0004] To achieve the above-mentioned object, an embodiment of the present invention provides an integrated inductor, comprising a magnetic core and a winding, wherein the magnetic core comprises a magnetic core center column, a first side column, a second side column, an upper magnetic core bottom plate, and a lower magnetic core bottom plate;

[0005] The winding includes a first inductor winding wound on a first side column, and a second inductor winding wound on a second side column;

[0006] The direction of the magnetic flux generated by the first inductor winding is opposite to the direction of the magnetic flux generated by the second inductor winding;

[0007] The magnetic flux density generated by the first inductor winding is different from the magnetic flux density generated by the second inductor winding;

[0008] Air gaps are provided on both the first side column and the second side column, and the air gaps of the first side column and the second side column are different.

[0009] To achieve the above-mentioned object, an embodiment of the present invention further provides an integrated circuit, comprising the above-mentioned integrated inductor.

[0010] The integrated inductor of the embodiment of the present invention has a design in which the magnetic fluxes of the two side legs are different due to the difference in the number of turns of the winding of the first side leg and the number of turns of the winding of the second side leg, or the difference in the air gap of the first side leg and the air gap of the second side leg, and the first inductor winding and the second inductor winding have opposite magnetic flux directions. In this way, the magnetic fluxes of the two side legs are different, and the fluxes are mutually weakened by the middle leg, so that the coil and the magnetic core of the magnetic element can be fully utilized. Since the number of turns of the two side leg windings is different, the number of turns of the side leg windings can be flexibly adjusted according to the actual proportion of copper loss and iron loss. At the same time, since the difference in the number of turns of the two side leg windings can be flexibly adjusted, corresponding optimization can also be achieved according to different heat dissipation requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0012] Figure 1 A schematic diagram of the structure and principle of an integrated inductor according to an embodiment of the present invention;

[0013] Figure 2 A schematic diagram showing a comparison of the core loss of an integrated inductor according to an embodiment of the present invention and an inductor with the same number of turns;

[0014] Figure 3 A schematic diagram of an embodiment of an integrated inductor applied to an interleaved boost converter according to an embodiment of the present invention;

[0015] Figure 4 FIG. 1 is a schematic diagram of an embodiment of an integrated inductor applied to an interleaved bridgeless totem converter according to an embodiment of the present invention. DETAILED DESCRIPTION

[0016] To make the above-mentioned objects, features and advantages of the present invention more clearly understood, the technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of the present application can be combined with each other in any manner.

[0017] The integrated inductor of the present invention achieves the purpose of mutually weakening the magnetic flux generated by the two side-leg windings on the center leg by virtue of the difference in the number of turns of the winding of the first side leg and the number of turns of the winding of the second side leg, or the difference in the air gap of the first side leg and the air gap of the second side leg; and the magnetic flux generated by the two side-leg windings is in opposite directions.

[0018] Example 1

[0019] Figure 1 FIG. 1 is a schematic diagram of the structure and principle of an integrated inductor according to an embodiment of the present invention. Figure 1 As shown, A and B represent the direction of current on the A and B sides respectively. The integrated inductor of the embodiment of the present invention includes a magnetic core and a winding. The magnetic core includes a magnetic core center column 101, a first side column 102, a second side column 103, an upper magnetic core 104, and a lower magnetic core 105; a first side column winding 106, a second side column winding 107; a first side column air gap 108 and a second side column air gap 109, wherein,

[0020] The core center column 101 , the first side column 102 , the second side column 103 , the upper magnetic core 104 , and the lower magnetic core 105 are integrally formed.

[0021] The first side leg winding 106 is disposed on the first side leg 102 to form a first inductor.

[0022] The second side column winding 107 is disposed on the second side column 103 to form a second inductor.

[0023] The first side column winding 106 and the second side column winding 107 have different numbers of winding turns.

[0024] A first side column air gap 108 is provided in the middle of the first side column 102 .

[0025] A second side column air gap 109 is provided in the middle of the second side column 103 .

[0026] The first side leg air gap 108 is different from the second side leg air gap 109 , and the core middle leg 101 has no air gap.

[0027] In the embodiment of the present invention, the first side column air gap 108 and the second side column air gap 109 can be a single-stage air gap or a multi-stage air gap;

[0028] The first side column winding 106 and the second side column winding 107 generate magnetic flux in opposite directions, and the two weaken each other on the center column. Since the first side column and the second side column have different numbers of winding turns and inconsistent air gaps, the magnetic flux density is different, that is, the magnetic flux of the first side column and the second side column is different, and they weaken each other through the center column instead of canceling each other out, so that part of the magnetic flux goes through the center column of the magnetic core, so that the magnetic element coil and the center column of the magnetic core can be fully utilized.

[0029] The different air gaps between the two side legs in the present embodiment are an inevitable characteristic of the two legs, given different numbers of turns and identical inductance. This characteristic also results in different magnetic fluxes generated by the two side legs. Therefore, the fluxes on the center leg are not completely canceled out, but rather weakened. When the currents are equal and the flux directions are opposite, some flux is diverted through the center leg, fully utilizing the core.

[0030] The magnetic flux Φ1 generated by the current in the first inductor winding and the magnetic flux Φ2 generated by the current in the second inductor winding are also unequal and in opposite directions. Φ1 and Φ2 have a mutually weakening effect on the core center column 101, thereby reducing the cross-sectional area of ​​the center column, and further reducing the core volume, reducing the core loss, and improving the circuit efficiency.

[0031] In the embodiment of the present invention, the upper magnetic core 104 and the lower magnetic core 105 are identical polygonal magnetic cores.

[0032] In the embodiment of the present invention, the first side pillar 102 and the second side pillar 103 are cylindrical, elliptical, or polygonal structures.

[0033] In the embodiment of the present invention, the magnetic core is a ferrite, amorphous, silicon steel or magnetic powder core.

[0034] In an embodiment of the present invention, an integrated structure of magnetic materials is utilized to wind wires on the two side poles, so that the current generates magnetic fluxes in opposite directions on the two side poles. Furthermore, since different air gaps are provided on the two side poles and there is no air gap on the middle pole, the magnetic fluxes of the two side poles weaken each other on the middle pole, thereby reducing the cross-sectional area of ​​the middle pole, thereby reducing the volume of the magnetic core, reducing the magnetic core loss, and improving the circuit efficiency.

[0035] Example 2

[0036] In the embodiment of the present invention, the upper magnetic core and the lower magnetic core may both be hexagonal or polygonal magnetic cores of the same shape.

[0037] In the embodiment of the present invention, the first side pillar and the second side pillar may both be cylinders, elliptical cylinders or polygonal prisms.

[0038] In an embodiment of the present invention, the first side column and the second side column both have one or more air gaps, and the air gaps of the first side column are different from the air gaps of the second side column.

[0039] In the embodiment of the present invention, the first side column and the second side column share the magnetic circuit of the center column of the magnetic core, but the magnetic circuits generated by the two side columns do not affect each other.

[0040] In an embodiment of the present invention, the number of turns of the winding on the first side pole is different from the number of turns of the winding on the second side pole.

[0041] In the embodiment of the present invention, the magnetic core material is ferrite, amorphous, silicon steel or magnetic powder core.

[0042] Example 3

[0043] Figure 2 FIG. 1 is a schematic diagram comparing the core loss of an integrated inductor according to an embodiment of the present invention and an inductor with the same number of turns; FIG. Figure 2As shown in this diagram, the horizontal axis represents time, i.e., a number of switching cycles, and the vertical axis represents loss. As time increases, the horizontal axis extends; as the vertical axis extends, the loss increases.

[0044] When the winding ratios of the two side columns are the same (e.g. 25:25, Figure 2 As shown in Figure 2), the core loss at the same time is much higher than that of the same integrated inductor when the two side column windings are different (for example, 35:25, as shown in Figure 2). Figure 2 core losses as shown).

[0045] As can be seen from the above diagram, when the same number of coil turns (all 25 turns) is used, the magnetic loss is relatively large, which affects the efficiency. Considering that one group of coils has poor heat dissipation, the number of turns of another group of coils with good heat dissipation is increased (for example, increased to 35 turns). The loss is significantly reduced, the efficiency is improved, and heat dissipation is taken into account.

[0046] In the embodiments of the present invention, the number of coil turns can be adjusted in actual design based on actual conditions. Increasing the number of turns on one side of the winding results in increased copper loss, decreased magnetic loss, and an increased air gap. Reducing the number of turns on one side of the winding results in decreased copper loss, increased magnetic loss, and a decreased air gap. This allows for flexible adjustments based on the actual proportion of copper and iron losses in practical applications, improving efficiency.

[0047] In another embodiment of the present invention, in actual applications, whether the inductor is designed for natural or air-cooled cooling, it has both an inlet and a leeward side, and can be located near or far from a heat source. Differentiated optimal designs can be implemented based on actual conditions. For example, if the inductor's inlet side has better heat dissipation, the number of turns can be increased to reduce magnetic losses. Alternatively, if the inductor's inlet side has poor heat dissipation, the number of turns can be reduced to reduce copper losses.

[0048] In this case, differentiated designs are made based on heat dissipation and efficiency considerations, and a compromise is made between magnetic loss and copper loss to maximize the utilization of the magnetic component coils and cores.

[0049] Example 4

[0050] Figure 3 FIG. 1 is a schematic diagram of an embodiment of an integrated inductor according to the present invention applied to an interleaved boost converter. Figure 3 As shown in the figure, when the power switch tube is turned on, the inductor stores energy; after the power switch tube is turned off, the energy on the inductor is released through the diode.

[0051] like Figure 3In the solution shown, if the integrated inductor is a conventional discrete inductor, multiple independent magnetic components will occur, occupying a large area, thus affecting the layout of other components on the printed circuit board (PCB). In addition, it is impossible to perform differentiated design of the core loss and winding copper loss of the magnetic components based on actual conditions.

[0052] The integrated inductor of the present invention utilizes a design that differs the number of turns of the windings on the first and second side legs, or the air gaps between the first and second side legs, and that directs the magnetic flux of the first and second inductor windings in opposite directions. This results in different magnetic fluxes on the two side legs, which are mutually weakened by the center leg, maximizing the utilization of the magnetic element coils and core. Furthermore, since the number of turns of the two side leg windings differs, they can be flexibly adjusted based on the actual ratio of copper loss to iron loss. Furthermore, since the ratio of the turns of the two side leg windings can be flexibly adjusted, corresponding optimization can be achieved based on different heat dissipation requirements.

[0053] Example 5

[0054] Figure 4 FIG. 1 is a schematic diagram of an embodiment of an integrated inductor according to the present invention applied to an interleaved bridgeless totem converter. Figure 4 As shown, during the positive half-cycle of the input voltage, power switch S6 remains open, while branches S1 (S3) and S2 (S4) operate at high frequency. Similarly, during the negative half-cycle of the input voltage, S5 remains open, while branches S1 (S3) and S2 (S4) operate at high frequency. Through a series of control algorithms, the input current follows the input voltage, achieving power factor correction and energy transfer.

[0055] like Figure 4 In the solution shown, if the integrated inductor is a conventional discrete inductor, the multiple magnetic components will be independent of each other, occupying a large area, thus affecting the layout of other components on the printed circuit board (PCB). In addition, it is impossible to perform differentiated design of the core loss and winding copper loss of the magnetic components based on actual conditions.

[0056] If the integrated inductor of the present invention is used, by varying the number of turns of the windings on the first and second side legs, or by varying the air gaps between the first and second side legs, and by designing the magnetic flux of the first and second inductor windings to be in opposite directions, the magnetic fluxes of the two side legs are designed to be different, which in turn are weakened by the center leg, maximizing the utilization of the magnetic element coils and core. Furthermore, since the number of turns of the two side legs differs, the ratio of copper loss to iron loss can be flexibly adjusted based on the actual ratio. Furthermore, since the ratio of the turns of the two side legs can be flexibly adjusted, it can be optimized according to different heat dissipation requirements.

[0057] Although the embodiments disclosed herein are as described above, the contents described herein are merely embodiments for facilitating understanding of the present invention and are not intended to limit the present invention. Any person skilled in the art may make any modifications and variations in the form and details of the embodiments without departing from the spirit and scope of the present invention. However, the scope of patent protection of the present invention shall remain subject to the scope defined by the appended claims.

Claims

1. An integrated inductor, characterized in that it comprises a magnetic core and a winding, wherein the magnetic core comprises a core center leg, a first side leg, a second side leg, an upper core bottom plate, and a lower core bottom plate; The winding includes a first inductor winding wound on the first side column, and a second inductor winding wound on the second side column; The direction of the magnetic flux generated by the first inductor winding is opposite to the direction of the magnetic flux generated by the second inductor winding; The magnetic flux density generated by the first inductor winding is different from the magnetic flux density generated by the second inductor winding; The first side column and the second side column are both provided with an air gap, and the air gap of the first side column is different from the air gap of the second side column; The number of turns of the first inductor winding and the second inductor winding are different. The number of turns of the first inductor winding and the second inductor winding are adjusted according to the heat dissipation effect and / or according to the actual proportion of copper loss and iron loss. The air gap of the first side column and the air gap of the second side column are determined according to the number of turns of the first inductor winding and the second inductor winding.

2. The inductor as claimed in claim 1 , wherein the first inductor winding and the second inductor winding have different numbers of turns.

3. The inductor as described in claim 1 is characterized in that the air gap of the first side column and the air gap of the second side column are single-segment air gaps or multi-segment air gaps.

4. The inductor as described in claim 1 is characterized in that the central column of the magnetic core has no air gap.

5. The inductor according to any one of claims 1 to 4, wherein the upper magnetic core bottom plate, the lower magnetic core bottom plate, the magnetic core middle column, the first side column and the second side column are of an integrated design.

6. The inductor as described in claim 5 is characterized in that the upper magnetic core base plate and the lower magnetic core base plate are polygonal magnetic cores.

7. The inductor as described in claim 5 is characterized in that the first side column and the second side column are cylinders, elliptical cylinders or polygonal prisms.

8. The inductor according to claim 7, wherein the magnetic core is ferrite, amorphous, silicon steel or magnetic powder core.

9. An integrated circuit, characterized in that it comprises: The integrated inductor according to any one of claims 1 to 8.

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