Array-type power inductor, switching power supply system device

Abstract

This array-type power inductor comprises: two or more main conductors that each have a non-turning linear steric structure and individually form a plurality of inductors; a magnetic body comprising a magnetic material that forms magnetic paths of magnetic fluxes generated by electric current flowing through the plurality of main conductors; and a plurality of external terminals that are disposed outside the magnetic body and that are electrically connected to the respective main conductors. The plurality of main conductors are disposed in parallel with each other so as to have a structure in which the magnetic body is present at the adjacent inner sides of the main conductors. The plurality of external terminals are connected to an external power conversion circuit such that current flows in the same direction through the plurality of main conductors. The magnetic body comprises: an inner leg part at the inner side where the plurality of main conductors are adjacent to each other; and outer leg parts at the outer sides where the main conductors are not adjacent to each other. The inner leg part has a first gap that forms a first magnetic path for a magnetic flux which passes along the inner leg part, in magnetic fluxes generated by electric current flowing through one of the main conductors. Each of the outer leg parts has a second gap that forms a second magnetic path for a magnetic flux that does not pass along the inner leg part but passes along the outer leg part, in the magnetic fluxes generated by electric current flowing through the one of the main conductors. The magnetic fluxes generated by electric current flowing in the same direction through the plurality of main conductors cause a physical phenomenon of cancelling each other at the inner leg part and strengthening each other at the outer leg parts. The array-type power inductor is provided with a structure in which the magnetic resistance formed by the second gap is greater than that formed by the first gap, and the plurality of inductors are integrally formed, the inductors having a magnetic structure in which the entirety, including the inner leg part, the outer leg parts, the first gap, and the second gap, is integrated.

Description

Technical Field

[0001] The present invention relates to an array-type power inductor including a plurality of power inductors.

Background Art

[0002] Patent Document 1 describes an inductor including two straight windings, a U-shaped magnetic core, and an I-shaped magnetic core.

[0003] The two straight windings are sandwiched between the U-shaped magnetic core and the I-shaped magnetic core and are arranged to run parallel to each other. There is no magnetic body between the two straight windings, and there is a gap.

[0004] In such a configuration, by flowing currents in opposite directions through the two straight windings, a large negative mutual inductance is obtained.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the configuration of Patent Document 1, when currents are flowed in the same direction through the two straight windings, the magnetic fluxes cancel each other out in the central magnetic path between the two straight windings. For this reason, the magnetic flux density becomes small and the inductance becomes small.

[0007] When the inductance is small, the effective value of the inductor current increases. Therefore, when this inductor is applied to a power conversion system, the conduction loss power loss in the power conversion system increases, and the output voltage ripple becomes large, resulting in a deterioration of the power supply quality.

[0008] Therefore, the object of the present invention is to provide an array-type power inductor that allows for arbitrary adjustment of self-inductance and mutual inductance, enabling miniaturization of magnetic components while obtaining a large inductance. [Means for solving the problem]

[0009] The array-type power inductor of this invention has a non-rotating linear three-dimensional structure and comprises two or more lead bodies, each individually constituting multiple inductors; a magnetic body made of a magnetic material that forms a magnetic path for the magnetic flux generated by the current flowing through the multiple lead bodies; and multiple external terminals arranged outside the magnetic body and electrically connected to each of the multiple lead bodies. The multiple lead bodies are arranged in parallel with a structure in which the magnetic body exists inside adjacent to each other. The multiple external terminals are connected to an external power conversion circuit so that the direction of the current flowing through the multiple lead bodies is the same. The magnetic body comprises an inner leg portion on the inside where the multiple lead bodies are adjacent, and an outer leg portion on the outside where the multiple lead bodies are not adjacent. The inner leg portion has a first gap that forms a first magnetic path for the magnetic flux passing through the inner leg portion, which is generated when current flows through one of the lead bodies. The outer leg portion forms a second magnetic path for the magnetic flux passing through the outer leg portion, which does not pass through the inner leg portion, which is generated when current flows through one of the lead bodies. The magnetic flux generated by currents flowing in the same direction through multiple inductors causes a physical phenomenon in which the inner legs cancel each other out and the outer legs reinforce each other. The magnetic resistance formed by the second gap is greater than the magnetic resistance formed by the first gap. The entire structure, including the inner legs, outer legs, first gap, and second gap, is an integrated magnetic material structure, and the structure comprises multiple inductors integrated together.

[0010] In this configuration, a magnetic material is present in the inner leg portion, and gaps are formed in the inner and outer leg portions, respectively. These gaps appropriately set the magnetoresistance of the outer leg portion, which affects the self-inductance, and the magnetoresistance of the inner leg portion, which affects the coupling inductance. [Effects of the Invention]

[0011] According to this invention, the self-inductance and mutual inductance can be arbitrarily adjusted, and by controlling the magnitude of the magnetic flux density in the magnetic material, magnetic saturation can be suppressed to obtain a large inductance, while miniaturizing composite magnetic components that have multiple inductors arranged in an array type. Furthermore, by arbitrarily setting the number of lead members corresponding to windings and the number of inner legs of the magnetic material corresponding to the core, an array-type power inductor with a small, scalable structure having an integrated magnetic material structure can be realized, enabling scalable response according to the power specifications of the power conversion circuit. There is no need to design an inductor structure for each power specification, which has the effect of shortening the development and design period of switching power supply devices. In addition, in the development and design of power conversion circuits, there is no need to prepare a wide variety of inductors based on structures that are individually designed to meet power specifications, which simplifies the manufacturing management and inventory management of inductors, and also simplifies the evaluation of the electrical characteristics of inductors. As a result, the efficiency and performance of switching power supply devices can be improved, as well as cost reduction and improved reliability in terms of quality. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is an equivalent circuit diagram of a switching power supply system device according to the first embodiment of the present invention. [Figure 2] Figure 2 is an external perspective view of an array-type power inductor according to the first embodiment of the present invention. [Figure 3] Figure 3 is an exploded perspective view of an array-type power inductor according to the first embodiment of the present invention. [Figure 4] Figure 4 is a four-view drawing of an array-type power inductor according to the first embodiment of the present invention. [Figure 5] Figure 5 is a side view enlarged showing an example of the current and magnetic flux states of an array-type power inductor according to the first embodiment. [Figure 6] Figure 6 is a side view enlarged showing an example of the configuration and current and magnetic flux states of an array-type power inductor according to a second embodiment of the present invention. [Figure 7]FIG. 7 is an enlarged side view showing a configuration of an array-type power inductor and examples of current and magnetic flux states according to a third embodiment of the present invention. [Figure 8] FIG. 8 is an exploded perspective view of an array-type power inductor according to a fourth embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0013] [First Embodiment] An array-type power inductor and a switching power supply system device according to a first embodiment of the present invention will be described with reference to the drawings.

[0014] (Circuit Configuration of a Switching Power Supply System Device Equipped with an Array-Type Power Inductor) FIG. 1 is an equivalent circuit diagram of a switching power supply system device according to a first embodiment of the present invention. As shown in FIG. 1, the switching power supply system device 80 includes an array-type power inductor 10, a power semiconductor IC 81, a power semiconductor IC 82, and a capacitor .

[0015] The power semiconductor 81 includes a driver circuit 810, a switching element Q81H, and a switching element Q81L. The power semiconductor 82 includes a driver circuit 820, a switching element Q82H, and a switching element Q82L. The switching elements Q81H, Q81L, Q82H, and Q82L are power semiconductor elements, for example, power MOSFETs.

[0016] The array-type power inductor 10 includes an inductor 11 and an inductor 12. The array-type power inductor 10 includes a first input terminal P101, a second input terminal P201, a first output terminal P102, and a second output terminal P202.

[0017] A DC power supply is connected between the Hi-side power input terminal and the Low-side power input terminal of the switching power supply system device 80. The Hi-side power input terminal is connected to the positive electrode of the DC power supply, and the Low-side power input terminal is connected to the negative electrode of the DC power supply.

[0018] The driver circuit 810 is connected to the gate terminal of the switching element Q81H and the gate terminal of the switching element Q81L.

[0019] The drain terminal of the switching element Q81H is connected to the Hi-side power input terminal of the switching power supply system device 80. The source terminal of the switching element Q81H is connected to the drain terminal of the switching element Q81L. The source terminal of the switching element Q81L is connected to the Low-side power input terminal (the terminal connected to the reference potential line) of the switching power supply system device 80. The reference potential line connects the Low-side power input terminal (the terminal connected to the negative electrode of the DC power supply) of the switching power supply system device 80 and the Low-side output terminal (the terminal connected to the negative electrode of the load 89) of the switching power supply system device 80.

[0020] The node between the source terminal of the switching element Q81H and the drain terminal of the switching element Q81L is connected to the first input terminal P101 of the array-type power inductor 10. The first input terminal P101 is connected to one terminal of the inductor 11. The other terminal of the inductor 11 is connected to the first output terminal P102. Note that one terminal of the inductor 11 may be the first input terminal P101, and similarly, the other terminal of the inductor 11 may be the first output terminal P102.

[0021] These power semiconductors 81 (driver circuit 810, switching element Q81H, switching element Q81L), and the inductor 11 constitute the first power conversion circuit.

[0022] The driver circuit 820 is connected to the gate terminal of the switching element Q82H and the gate terminal of the switching element Q82L.

[0023] The drain terminal of switching element Q82H is connected to the Hi-side power input terminal of the switching power supply system device 80. The source terminal of switching element Q82H is connected to the drain terminal of switching element Q82L. The source terminal of switching element Q82L is connected to the Low-side power input terminal (the terminal connected to the reference potential line) of the switching power supply system device 80.

[0024] The node between the source terminal of switching element Q82H and the drain terminal of switching element Q82L is connected to the second input terminal P201 of the array-type power inductor 10. The second input terminal P201 is connected to one terminal of inductor 12. The other terminal of inductor 12 is connected to the second output terminal P202. Note that one terminal of inductor 12 may be the second input terminal P201, and similarly, the other terminal of inductor 12 may be the second output terminal P202.

[0025] These power semiconductors 82 (driver circuit 820, switching element Q82H, switching element Q82L) and inductor 12 constitute the second power conversion circuit.

[0026] The first output terminal P102 and the second output terminal P202 are connected, and this node is connected to the Hi-side output terminal of the switching power supply system device 80.

[0027] Capacitor 88 is a smoothing capacitor and is connected between the Hi-side output terminal and the Low-side output terminal, which is connected to a reference potential line.

[0028] With the above configuration, the switching power supply system 80 includes a first power conversion circuit and a second power conversion circuit connected in parallel. The number of power conversion circuits connected in parallel is not limited to two. The number of power conversion circuits, each including an inductor, is set according to the current required by the load 89, which is an external electrical circuit. This makes it possible to realize a scalable switching power supply system 80.

[0029] (Array-type power inductor) Figure 2 is an external perspective view of an array-type power inductor according to the first embodiment of the present invention. Figure 3 is an exploded perspective view of an array-type power inductor according to the first embodiment of the present invention. Figure 4 is a quadrature view of an array-type power inductor according to the first embodiment of the present invention. Figure 4 shows a plan view (view from the side opposite to the mounting surface), a first end view, a second end view, and a first side view. In each figure, the three orthogonal axes are referred to as the X-axis, Y-axis, and Z-axis, but these are axis names used for the sake of ease of explanation and do not limit, for example, the direction in which the array-type power inductor 10 is used.

[0030] As shown in Figures 2, 3, and 4, the array-type power inductor 10 comprises a magnetic material 21, a magnetic material 22, a lead body 31, and a lead body 32.

[0031] (Magnetic material 21) The magnetic material 21 is a so-called E-shaped core.

[0032] The magnetic material 21 has a main plane 21F11, a main plane 21F12, a main plane 21F13, a main plane 21F2, an end face 21E1, an end face 21E2, a side surface 21S1, and a side surface 21S2. The main planes 21F11, 21F12, 21F13, and 21F2 face each other and are perpendicular to the Z-axis direction (the thickness direction of the magnetic material 21).

[0033] The magnetic material 21 has grooves 211 and 212 that extend in the Y-axis direction. Grooves 211 and 212 are formed with a gap in the X-axis direction (the longitudinal direction of the magnetic material 21). The formation of grooves 211 and 212 in the magnetic material 21 forms main planes 21F11, 21F13, and 21F12.

[0034] The end faces 21E1 and 21E2 face each other, are parallel to the X-axis direction (the direction of the long side of the magnetic material 21 in this embodiment), and perpendicular to the Y-axis direction (the direction of the short side of the magnetic material 21 in this embodiment). The side faces 21S1 and 21S2 face each other, are parallel to the Y-axis direction, and perpendicular to the X-axis direction.

[0035] End faces E21 and E22 connect main planes 21F11, 21F12, and 21F13 to main plane 21F2. Side faces 21S1 and 21S2 connect main planes 21F11, 21F12, and 21F13 to main plane 21F2, and connect end faces E21 and E22.

[0036] As a result, the magnetic material 21 realizes an E-shaped core having grooves 211 and 212, surrounded by a main plane 21F11, a front main plane consisting of main planes 21F12, main planes 21F13 and 21F2, a back main plane 21F2, an end face E21, an end face E22, a side surface 21S1, and a side surface 21S2.

[0037] The distance between the main plane 21F11 and the main plane 21F2, that is, the height HO of the portion corresponding to the first outer leg in the magnetic material 21, is the same as the distance between the main plane 21F12 and the main plane 21F2, that is, the height HO of the portion corresponding to the second outer leg in the magnetic material 21.

[0038] The distance between the main plane 21F13 and the main plane 21F2, that is, the height HI of the portion corresponding to the inner leg in the magnetic material 21, is higher than the height HO of the portions corresponding to the first and second outer legs.

[0039] (Magnetic material 22) The magnetic material 22 is a flat plate and is a so-called I-shaped core. The magnetic material 22 comprises a main plane 22F1, a main plane 22F2, an end face 22E1, an end face 22E2, a side surface 22S1, and a side surface 22S2. The main planes 22F1 and 22F2 face each other, the end faces 22E1 and 22E2 face each other, and the side surfaces 22S1 and 22S2 face each other.

[0040] (Magnetic material 20) The magnetic material 20 is composed of a combination of magnetic material 21 and magnetic material 22.

[0041] The magnetic material 22 is positioned on the main planes 21F11, 21F12, and 21F13 of the magnetic material 21. In this case, the main plane 22F2 of the magnetic material 22 faces the main planes 21F11, 21F12, and 21F13 of the magnetic material 21.

[0042] Magnetic material 21 and magnetic material 22 are fixed together by adhesives 51, 52, and 53 placed between the main planes 21F11, 21F12, and 21F13 of magnetic material 21 and the main plane 22F2 of magnetic material 22.

[0043] This results in a magnetic body 20 consisting of magnetic material 21 and magnetic material 22. The end face 21E1 of magnetic material 21 and the end face 22E1 of magnetic material 22 are substantially flush, and the end face 21E2 of magnetic material 21 and the end face 22E2 of magnetic material 22 are substantially flush. The side surface 21S1 of magnetic material 21 and the side surface 22S1 of magnetic material 22 are substantially flush, and the side surface 21S2 of magnetic material 21 and the side surface 22S2 of magnetic material 22 are substantially flush.

[0044] Therefore, the magnetic material 20 is a roughly rectangular parallelepiped having a main plane 20F1 (composed of main plane 22F1), a main plane 20F2 (composed of main plane 21F2), an end face 20E1 (composed of end faces 21E1 and 22E1), an end face 20E2 (composed of end faces 21E2 and 22E2), a side surface 20S1 (composed of side surfaces 21S1 and 22S1), and a side surface 20S2 (composed of side surfaces 21S2 and 22S2).

[0045] In this configuration, the magnetic material 20 comprises a first outer leg portion 20ZO1 on the side surface 20S1 side of the groove 211 forming portion, an inner leg portion 20ZI between the groove 211 forming portion and the groove 212 forming portion, and a second outer leg portion 20ZO2 on the side surface 20S2 side of the groove 212 forming portion (see Figure 2).

[0046] The width WO of the first outer leg 20ZO1 and the width WO of the second outer leg 20ZO2 are the same. The width WI of the inner leg is greater than or equal to the width WO of the first outer leg 20ZO1 and the second outer leg 20ZO2, and less than or equal to twice the width WO of the first outer leg 20ZO1 and the second outer leg 20ZO2.

[0047] Here, the thicknesses of adhesives 51 and 52 are approximately the same, while the thickness of adhesive 53 is thinner than the thicknesses of adhesives 51 and 53. Furthermore, the magnetic permeability of adhesives 51, 52, and 53 is lower than that of magnetic material 21 and magnetic material 22.

[0048] As a result, a magnetic gap 41 (second gap) with height (gap width) go is formed between the main plane 21F1 and the main plane 22F2, i.e., in the first outer leg portion 20ZO1. A magnetic gap 42 (second gap) with height (gap width) go is formed between the main plane 21F2 and the main plane 22F2, i.e., in the second outer leg portion 20ZO2.

[0049] Furthermore, a magnetic gap 43 (first gap) with height (gap width) gi is formed between the main plane 21F3 and the main plane 22F2, that is, in the inner leg portion 20ZI.

[0050] Furthermore, by having the above configuration (height HI < height HO), the height gi of the magnetic gap 43 of the inner leg portion 20ZI is smaller than the heights go of the magnetic gaps 41 and 42 of the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2 (see Figures 4 and 5).

[0051] (Leader 31, Leader 32) Leading elements 31 and 32 have the same shape. Here, "same shape" includes within the range of manufacturing tolerances and within the range of variation in the characteristics of the array-type power inductor 10.

[0052] The lead members 31 and 32 are realized by bending metal plates of a predetermined thickness and width. The thickness and width of the lead members 31 and 32 are set based on the electrical resistance values ​​of the lead members 31 and 32 that are permitted by the specifications of the array-type power inductor 10 and the switching power supply system device 80. The length of the lead members 31 and 32 is set based on the inductance of the array-type power inductor 10 (inductor 11 and inductor 12).

[0053] The main body 320 comprises a main section 310, a first terminal section 311, and a second terminal section 312. The first terminal section 311 is connected to one end of the main section 310 in the direction in which it extends, and the second terminal section 312 is connected to the other end of the main section 310 in the direction in which it extends. The directions in which the first terminal section 311 and the second terminal section 312 extend are substantially perpendicular to the direction in which the main section 320 extends.

[0054] The main body 32 comprises a main section 320, a first terminal section 321, and a second terminal section 322. The first terminal section 321 is connected to one end of the main section 320 in the direction in which it extends, and the second terminal section 322 is connected to the other end of the main section 320 in the direction in which it extends. The directions in which the first terminal section 321 and the second terminal section 322 extend are substantially perpendicular to the direction in which the main section 320 extends.

[0055] (Placement of the lead members 31 and 32 on the magnetic material 20) The main body 31 is positioned such that the main part 310 is fitted into the groove 211 of the magnetic body 20. At this time, the first terminal portion 311 is positioned opposite the end face 20E1 of the magnetic body 20 (end face 21E1 of the magnetic body 21), and the second terminal portion 312 is positioned opposite the end face 20E2 of the magnetic body 20 (end face 21E2 of the magnetic body 21).

[0056] The main body 32 is positioned such that the main part 320 is fitted into the groove 212 of the magnetic body 20. At this time, the first terminal portion 321 is positioned facing the end face 20E1 of the magnetic body 20 (end face 21E1 of the magnetic body 21), and the second terminal portion 322 is positioned facing the end face 20E2 of the magnetic body 20 (end face 21E2 of the magnetic body 21).

[0057] In this configuration, the tip of the first terminal portion 311 and the tip of the second terminal portion 312 of the lead body 31, and the tip of the first terminal portion 321 and the tip of the second terminal portion 322 of the lead body 32 are mounted on the circuit board that constitutes the switching power supply system device 80.

[0058] In this configuration, the first terminal portion 311 of the lead unit 31 is connected to the output terminal of the power semiconductor IC 81, and the second terminal portion 312 of the lead unit 31 is connected to the Hi-side output terminal of the switching power supply system device 80. Therefore, the first terminal portion 311 of the lead unit 31 or its tip becomes the first input terminal P101 of the array-type power inductor 10, and the second terminal portion 312 of the lead unit 31 or its tip becomes the first output terminal P102 of the array-type power inductor 10.

[0059] Furthermore, the first terminal portion 321 of the lead unit 32 is connected to the output terminal of the power semiconductor IC 82, and the second terminal portion 322 of the lead unit 32 is connected to the Hi-side output terminal of the switching power supply system device 80. Therefore, the first terminal portion 321 of the lead unit 32 or its tip becomes the second input terminal P201 of the array-type power inductor 10, and the second terminal portion 322 of the lead unit 32 or its tip becomes the second output terminal P202 of the array-type power inductor 10.

[0060] (Current and magnetic flux of array-type power inductor 10) Figure 5 is a side view enlarged showing an example of the current and magnetic flux states of an array-type power inductor according to the first embodiment.

[0061] With the above configuration, current flows in the same direction through the lead members 31 that constitute the inductor 11 and the lead members 32 that constitute the inductor 12 of the array-type power inductor 10 (from the front to the back of the page in Figure 5).

[0062] As a result, a magnetic flux Φ31 is generated around the main part 310 of the main body 31, forming the self-inductance of the inductor 11. A magnetic flux Φ32 is generated around the main part 320 of the main body 32, forming the self-inductance of the inductor 12.

[0063] In the inner leg portion 20ZI between the adjacent main body 31 and main body 32, the direction of magnetic flux Φ31 and the direction of magnetic flux Φ32 are opposite. Therefore, magnetic flux Φ31 and magnetic flux Φ32 cancel each other out.

[0064] On the other hand, at the first outer leg portion 20ZO1 on the side 20S1 where there are no other leading bodies adjacent to the leading body 31, the directions of magnetic flux Φ31 and magnetic flux Φ32 are the same. Therefore, magnetic flux Φ31 and magnetic flux Φ32 create a constructive interference phenomenon.

[0065] Similarly, at the second outer leg portion 20ZO2 on the side 20S2 where no other leading bodies are adjacent to the leading body 32, the directions of magnetic flux Φ31 and magnetic flux Φ32 are the same. Therefore, magnetic flux Φ31 and magnetic flux Φ32 create a constructive interference phenomenon.

[0066] As a result, as shown in Figure 4, a magnetic flux Φ33 is generated that forms a coupled inductance, passing through the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2, but not through the inner leg portion 20ZI.

[0067] Here, as described above, the inner leg portion 20ZI has a magnetic material and a magnetic gap 43. The first outer leg portion 20ZO1 has a magnetic material and a magnetic gap 41. The second outer leg portion 20ZO2 has a magnetic material and a magnetic gap 42.

[0068] Furthermore, the height go of magnetic gaps 41 and 42 is greater than the height gi of magnetic gap 43.

[0069] In this configuration, the presence of a magnetic material in the inner leg portion 20ZI and the small height gi of the magnetic gap 43 allow for a lower magnetic resistance in the magnetic path (first magnetic path) passing through the inner leg portion 20ZI. Therefore, even in the inner leg portion 20ZI where magnetic fluxes cancel each other out, a magnetic path (first magnetic path) can be formed through which the magnetic flux Φ31 that forms the self-inductance of the inductor 11 due to the current i31 flowing through the main body 31 passes. Similarly, a magnetic path (first magnetic path) can be formed through which the magnetic flux Φ32 that forms the self-inductance of the inductor 12 due to the current i32 flowing through the main body 32 passes. Furthermore, since undesirable coupling between magnetic flux Φ31 and magnetic flux Φ32 is suppressed, the width WI of the inner leg portion 20ZI can be reduced.

[0070] In addition, since the heights go of the magnetic gaps 41 and 42 are large, the magnetic resistance of the magnetic path (the second magnetic path) passing through the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2 can be increased. Therefore, magnetic saturation can be suppressed in the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2 where the magnetic fluxes reinforce each other.

[0071] As a result, the array-type power inductor 10 can achieve miniaturization and high performance. Furthermore, since the conductor 31 and the conductor 32 have a non-rotating linear three-dimensional structure, the array-type power inductor 10 can reduce the resistance values of the conductor 31 and the conductor 32, and reduce losses. Thereby, the array-type power inductor 10 can achieve high efficiency. In particular, in the switching power supply system device 80, high currents flow through the inductors 11 and 12. Therefore, by applying the array-type power inductor 10 to the switching power supply system device 80, high efficiency can be achieved for the switching power supply system device 80.

[0072] Also, in this configuration, by appropriately adjusting the height go of the magnetic gaps 41 and 42 and the height gi of the magnetic gap 43 while satisfying the relationship gi < go, as a coupled inductor, the self-inductance and the mutual inductance can be arbitrarily adjusted. For example, the magnitudes of the magnetic flux densities of the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2 and the magnitude of the magnetic flux density of the inner leg portion 20ZI can be made approximately uniform. Thereby, the balance between the self-inductance and the mutual inductance can be appropriately adjusted, and the volume of the magnetic material can be minimized while suppressing magnetic saturation even at the maximum magnetic flux density. The suppression of magnetic saturation in the inductor and the miniaturization of the inductor size can be optimized. By these, miniaturization of the inductor can be realized, miniaturization of component mounting in the power conversion circuit can be achieved, and a highly efficient and small-sized and lightweight switching power supply system can be realized.

[0073] Thus, the array-type power inductor 10 can simultaneously achieve desired characteristics and miniaturization.

[0074] Furthermore, in this configuration, multiple inductors can be realized with a single array-type power inductor 10. This reduces the mounting area on the circuit board compared to forming multiple inductors individually, and for example, allows for miniaturization of the switching power supply system device 80.

[0075] Furthermore, by arbitrarily setting the number of lead members corresponding to windings and the number of inner legs of the magnetic material corresponding to the core, an array-type power inductor with a compact, scalable structure featuring an integrated magnetic material structure can be realized, enabling scalable adaptation to the power specifications of power conversion circuits. This eliminates the need to design an inductor structure for each power specification, resulting in a reduction in the development and design period of switching power supplies. In addition, during the development and design of power conversion circuits, there is no need to prepare a wide variety of inductors based on individually designed structures to meet power specifications, simplifying inductor manufacturing and inventory management, as well as simplifying the evaluation of inductor electrical characteristics. As a result, switching power supplies can be made more efficient and high-performance, while also achieving cost reduction and improved reliability in terms of quality.

[0076] [Second Embodiment] An array-type power inductor according to a second embodiment of the present invention will be described with reference to the figures. Figure 6 is an enlarged side view showing an example of the configuration and current and magnetic flux state of an array-type power inductor according to the second embodiment of the present invention.

[0077] As shown in Figure 6, the array-type power inductor 10A according to the second embodiment differs from the array-type power inductor 10 according to the first embodiment in the configuration of the magnetic material 20A. The other configurations of the array-type power inductor 10A are the same as those of the array-type power inductor 10, and the explanation of the similar parts will be omitted.

[0078] The magnetic body 20A of the array-type power inductor 10A includes a magnetic body 21A. In the magnetic body 20A, the width WI of the inner leg portion 20ZI is larger than the width WO of the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2, and smaller than twice the value of the width WO (2×WO) (WO < WI < 2×WO).

[0079] With such a configuration, the array-type power inductor 10A exhibits the same operational effects as the array-type power inductor 10, and furthermore, the leakage magnetic flux can be reduced.

[0080] In the array-type power inductor 10A, the distance between the main plane 21F13 and the main plane 21F2 in the magnetic body 21A is the same as the distance between the main planes 21F11, 21F12 and the main plane 21F2. In other words, the height of the portion of the inner leg portion 20ZI formed of the magnetic body 21A is the same as the height of the portions of the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2 formed of the magnetic body 21A. Therefore, the height gi of the magnetic gap 43 of the inner leg portion 20ZI is the same as the height go of the magnetic gaps 41, 42 of the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2.

[0081] If the array-type power inductor 10A has the above-mentioned relationship of WO < WI < 2×WO, even if the height gi of the magnetic gap 43 of the inner leg portion 20ZI is made the same as the height go of the magnetic gaps 41, 42 of the first outer leg portion 20ZO1 and the second outer leg portion 20ZO2, the array-type power inductor 10A can exhibit the same operational effects as the array-type power inductor 10.

[0082] [Third Embodiment] The array-type power inductor according to the third embodiment of the present invention will be described with reference to the drawings. FIG. 7 is an enlarged side view showing an example of the configuration of the array-type power inductor according to the third embodiment of the present invention and the states of current and magnetic flux.

[0083] As shown in Figure 7, the array-type power inductor 10B according to the third embodiment differs from the array-type power inductor 10 according to the first embodiment in the configuration of the magnetic material 20B. The other configurations of the array-type power inductor 10B are the same as those of the array-type power inductor 10, and the explanation of the similar parts will be omitted.

[0084] In the array-type power inductor 10B, the magnetic material 21 and the magnetic material 22 are in contact at the inner leg portion 20ZI. In other words, there is no gap at the inner leg portion 20ZI.

[0085] With this configuration, the array-type power inductor 10B can achieve the same effects as the array-type power inductor 10.

[0086] [Fourth Embodiment] An array-type power inductor according to a fourth embodiment of the present invention will be described with reference to the figures. Figure 8 is an exploded perspective view of an array-type power inductor according to a fourth embodiment of the present invention.

[0087] As shown in Figure 8, the array-type power inductor 10C according to the fourth embodiment differs from the array-type power inductor 10 according to the first embodiment in the configuration of the magnetic materials 21C and 22C. The other configurations of the array-type power inductor 10C are the same as those of the array-type power inductor 10, and the explanation of the similar parts will be omitted.

[0088] In the magnetic material 21C, the distance H between the main plane 21F13 and the main plane 21F2 is the same as the distance H between the main planes 21F11, 21F12 and the main plane 21F2. In other words, the height of the portion of the inner leg 20ZI composed of the magnetic material 21C is the same as the height of the portions of the first outer leg 20ZO1 and the second outer leg 20ZO2 composed of the magnetic material 21C.

[0089] The magnetic material 22C has recesses 2291 and 2292 that are recessed from the main plane 22F2. The portion of the magnetic material 22C where the recess 2291 is formed faces the main plane 21F11 of the magnetic material 21C. The portion of the magnetic material 22C where the recess 2292 is formed faces the main plane 21F12 of the magnetic material 21C.

[0090] Thus, by forming recesses 2291 and 2292 in the magnetic material 22C, the array-type power inductor 10C can achieve the same configuration as the array-type power inductor 10. As a result, the array-type power inductor 10C can achieve the same effects as the array-type power inductor 10.

[0091] Although the above description does not specify the material of the magnetic material in detail, for example, the magnetic material is preferably a metallic magnetic material, and in particular, it is more preferable to use one of the following.

[0092] The magnetic material is a Mn-Zn ferrite material. This allows the magnetic material to achieve high relative permeability, resulting in a small size while still providing large inductance.

[0093] The magnetic material is a Mn-Ni ferrite material. This reduces hysteresis loss in the magnetic material during high-frequency operation. Therefore, when applied to a switching power supply system device 80, it enables highly efficient power conversion.

[0094] The configurations of each embodiment described above show a configuration with two lead bodies (two inductors). However, the number of lead bodies may be three or more. When there are three or more lead bodies, the magnetic material portion (including the magnetic gap) outside the ends where the lead bodies are aligned (on the side of the magnetic material) becomes the outer leg portion, and the magnetic material portion (including the magnetic gap) between adjacent lead bodies becomes the inner leg portion. With such a configuration, the self-inductance and mutual inductance can be arbitrarily adjusted in a scalable structure according to the output current of the switching power supply system device 80, and the magnetic components can be miniaturized while obtaining a large inductance.

[0095] Furthermore, the configurations of each of the above embodiments can be combined as appropriate, and effects corresponding to each combination can be achieved.

[0096] <1> It has a non-rotating linear three-dimensional structure, and consists of two or more lead bodies, each individually constituting multiple inductors, A magnetic material comprising a magnetic material that forms a magnetic path of magnetic flux generated by the current flowing through the plurality of main bodies, A plurality of external terminals arranged outside the magnetic material and electrically connected to each of the plurality of main bodies, Equipped with, The aforementioned multiple main bodies are arranged in parallel in a structure in which the magnetic material is present inside adjacent bodies. The aforementioned multiple external terminals are connected to an external power conversion circuit such that the direction of the current flowing through the multiple main bodies is the same. The magnetic material is The aforementioned multiple main bodies are adjacent to each other on the inner leg portion, The aforementioned multiple main bodies have outer leg portions that are not adjacent to each other, Equipped with, The inner leg portion has a first gap that forms a first magnetic path for the magnetic flux passing through the inner leg portion, which is generated when an electric current flows through one of the main bodies. The outer leg portion has a second gap that forms a second magnetic path for the magnetic flux that passes through the outer leg portion but does not pass through the inner leg portion, among the magnetic flux generated when current flows through one of the main bodies. The magnetic flux generated by currents flowing in the same direction through the multiple main members cancels out at the inner leg portion and reinforces at the outer leg portion, the magnetic resistance formed by the second gap is greater than the magnetic resistance formed by the first gap, and the entire structure, including the inner leg portion, the outer leg portion, the first gap, and the second gap, is an integrated magnetic material structure. An array-type power inductor having a structure in which the aforementioned multiple inductors are integrated together.

[0097] <2> The plurality of inductors have a scalable structure in which the output current obtained by merging the currents flowing through the plurality of lead members can correspond to the current output by the external power conversion circuit by setting the number of the plurality of lead members and the number of inner legs, and the entire structure is an integrated magnetic material structure. <1> Array-type power inductor.

[0098] <3> The width of the inner leg portion, which is the adjacent distance between the multiple main bodies, is set to be no more than twice the width of the outer leg portion, which is the distance between the side surface of the magnetic material and the main body closest to that side surface, and the magnitude of the magnetic flux density in the inner leg portion in the first magnetic path and the magnitude of the magnetic flux density in the outer leg portion in the second magnetic path are approximately uniform with respect to the magnetic flux generated when current flows in the same direction through the multiple main bodies. <1> or <2> Array-type power inductor.

[0099] <4> The width of the inner leg portion is greater than or equal to the width of the outer leg portion, and with respect to the magnetic flux generated when current flows in the same direction through the multiple leading elements, the magnitude of the magnetic flux density in the inner leg portion in the first magnetic path and the magnitude of the magnetic flux density in the outer leg portion in the second magnetic path are approximately uniform. <1> ~ <3> One of the following array-type power inductors.

[0100] <5> The width of the first gap is smaller than the width of the second gap, and with respect to the magnetic flux generated by currents flowing in the same direction through the multiple leading elements, the magnitude of the magnetic flux density at the inner leg in the first magnetic path and the magnitude of the magnetic flux density at the outer leg in the second magnetic path are approximately uniform. <1> ~ <4> One of the following array-type power inductors.

[0101] <6> The aforementioned magnetic material is a Mn-Zn ferrite material. <1> ~ <5> One of the following array-type power inductors.

[0102] <7> The aforementioned magnetic material is a Mn-Ni ferrite material. <1> ~ <5> One of the following array-type power inductors.

[0103] <8> The aforementioned magnetic material is a metallic magnetic material. <1> ~ <5> One of the following array-type power inductors.

[0104] <9> <1> ~ <8> One of the array-type power inductors and Multiple power conversion circuits, each configured using the aforementioned multiple inductors, An optimized switching power supply system device. [Explanation of symbols]

[0105] 10, 10A, 10B, 10C: Array-type power inductors 11, 12: Inductors 20, 20A, 20B, 21, 21A, 21C, 22, 22C: Magnetic material 20E1, 20E2: End face 20F1, 20F2: Main plane 20S1, 20S2: Side 20ZI: Inner leg 20ZO1: 1st outer leg 20ZO2: 2nd outer leg 21E1, 21E2: End face 21F11, 21F12, 21F13: Main plane 21S1, 21S2: Side 22E1, 22E2: End face 22F1, 22F2: Main plane 22S1, 22S2: Side 31, 32: Leader 41, 42, 43: Magnetic gap 51, 52, 53: Adhesive 80: Switching power supply system equipment 81, 82: Power semiconductor ICs 88: Capacitor 89: Load 211, 212: Groove 310: Main part 311: 1st terminal part 312:Second terminal section 320: Main part 321: 1st terminal section 322: 2nd terminal section 810, 820: Driver circuits 2291, 2292: Recess P101: First input terminal P102: First output terminal P201: Second input terminal P202: Second output terminal Q81H, Q81L, Q82H, Q82L: Switching elements

Claims

1. It has a non-rotating linear three-dimensional structure, and consists of two or more lead bodies, each individually constituting multiple inductors, A magnetic material comprising a magnetic material that forms a magnetic path of magnetic flux generated by the current flowing through the plurality of main bodies, A plurality of external terminals arranged outside the magnetic material and electrically connected to each of the plurality of main bodies, Equipped with, The aforementioned multiple main bodies are arranged in parallel in a structure in which the magnetic material is present inside adjacent bodies. The aforementioned multiple external terminals are connected to an external power conversion circuit such that the direction of the current flowing through the multiple main bodies is the same. The magnetic material is The aforementioned multiple main bodies are adjacent to each other on the inner leg portion, The aforementioned multiple main bodies have outer leg portions that are not adjacent to each other, Equipped with, The inner leg portion has a first gap that forms a first magnetic path for the magnetic flux passing through the inner leg portion, which is generated when an electric current flows through one of the main bodies. The outer leg portion has a second gap that forms a second magnetic path for the magnetic flux that passes through the outer leg portion but does not pass through the inner leg portion, among the magnetic flux generated when an electric current flows through one of the main bodies. The magnetic flux generated by the flow of current in the same direction through the multiple main members cancels out at the inner leg portion and reinforces at the outer leg portion, and the magnetic resistance formed by the second gap is made greater than the magnetic resistance formed by the first gap to suppress magnetic saturation at the outer leg portion where the magnetic flux reinforces each other, and the entire structure, including the inner leg portion, the outer leg portion, the first gap and the second gap, is an integrated magnetic material structure. The structure comprises the aforementioned multiple inductors integrated together. Array-type power inductor.

2. A plurality of lead bodies having a non-rotating linear three-dimensional structure, each individually constituting a plurality of inductors, A magnetic material comprising a magnetic material that forms a magnetic path of magnetic flux generated by the current flowing through the plurality of main bodies, A plurality of external terminals arranged outside the magnetic material and electrically connected to each of the plurality of main bodies, Equipped with, The aforementioned multiple main bodies are arranged in parallel in a structure in which the magnetic material is present inside adjacent bodies. The aforementioned multiple external terminals are connected to an external power conversion circuit such that the direction of the current flowing through the multiple main bodies is the same. The magnetic material is The aforementioned multiple main bodies are adjacent to each other on the inner leg portion, The aforementioned multiple main bodies have outer leg portions that are not adjacent to each other, Equipped with, The inner leg portion has a first gap that forms a first magnetic path for the magnetic flux passing through the inner leg portion, which is generated when an electric current flows through one of the main bodies. The outer leg portion has a second gap that forms a second magnetic path for the magnetic flux that passes through the outer leg portion but does not pass through the inner leg portion, among the magnetic flux generated when an electric current flows through one of the main bodies. The magnetic flux generated by currents flowing in the same direction through the multiple main members cancels out at the inner leg portion and reinforces at the outer leg portion, the magnetic resistance formed by the second gap is greater than the magnetic resistance formed by the first gap, and the entire structure, including the inner leg portion, the outer leg portion, the first gap, and the second gap, is an integrated magnetic material structure. The structure comprises the aforementioned multiple inductors integrated together, The width of the first gap is smaller than the width of the second gap, and with respect to the magnetic flux generated by currents flowing in the same direction through the plurality of leading elements, the magnitude of the magnetic flux density at the inner leg in the first magnetic path and the magnitude of the magnetic flux density at the outer leg in the second magnetic path are approximately uniform. Array-type power inductor.

3. The plurality of inductors have a scalable structure in which the output current obtained by merging the currents flowing through the plurality of lead members can correspond to the current output by the external power conversion circuit by setting the number of the plurality of lead members and the number of inner legs, and the entire structure is an integrated magnetic material structure. The array-type power inductor according to claim 1 or claim 2.

4. The width of the inner leg portion, which is the adjacent distance between the multiple main bodies, is set to be no more than twice the width of the outer leg portion, which is the distance between the side surface of the magnetic material and the main body closest to that side surface, and the magnitude of the magnetic flux density in the inner leg portion in the first magnetic path and the magnitude of the magnetic flux density in the outer leg portion in the second magnetic path are approximately uniform with respect to the magnetic flux generated when current flows in the same direction through the multiple main bodies. The array-type power inductor according to claim 1 or claim 2.

5. The width of the inner leg portion is greater than or equal to the width of the outer leg portion, and with respect to the magnetic flux generated when current flows in the same direction through the multiple leading elements, the magnitude of the magnetic flux density in the inner leg portion in the first magnetic path and the magnitude of the magnetic flux density in the outer leg portion in the second magnetic path are approximately uniform. The array-type power inductor according to claim 4.

6. The magnetic material is a Mn-Zn ferrite material. The array-type power inductor according to claim 1 or claim 2.

7. The magnetic material is a Mn-Ni ferrite material. The array-type power inductor according to claim 1 or claim 2.

8. The aforementioned magnetic material is a metallic magnetic material. The array-type power inductor according to claim 1 or claim 2.

9. An array-type power inductor according to claim 1 or claim 2, Multiple power conversion circuits, each configured using the aforementioned multiple inductors, An optimized switching power supply system device.

Images