Reactor, converter, and power conversion device

Abstract

This reactor is provided with a coil and a magnetic core having: an inner-side core part which is disposed inside the coil; and an outer-side core part which is disposed outside the coil. The coil has a winding which is wound so as to be along the outer peripheral surface of the inner-side core part. The outer peripheral shape of the coil, viewed in a first direction along the axis of the coil, is a rectangular shape. The outer peripheral surface of the coil has a first coil surface and a second coil surface which are opposite to each other and are along each of the long sides of the outer peripheral shape of the coil. The first coil surface and the second coil surface are exposed from the outer-side core part. At least the outer peripheral region of the inner-side core part is constituted of a molding of composite material, and the outer peripheral surface of the inner-side core part has a plurality of groove portions arranged in the direction along the axis of the inner-side core part. The winding in respective turns of the coil is disposed in the plurality of groove portions.

Description

Reactors, converters, and power conversion devices

[0001] This disclosure relates to a reactor, a converter, and a power conversion device. This application claims priority to Japanese Patent Application No. 2023-140530 filed on August 30, 2023, and incorporates by reference all of the contents of that application.

[0002] The reactor of Patent Document 1 includes a coil and a magnetic core. The coil has a pair of winding portions formed by spirally winding a wire. Each winding portion has a rectangular cylindrical shape. The magnetic core has a pair of inner core portions and a pair of outer core portions. Each inner core portion is disposed inside each winding portion. Each inner core portion has a rectangular column shape. Each outer core portion is disposed outside both winding portions.

[0003] JP 2013-219318 A

[0004] The reactor of the present disclosure includes a coil and a magnetic core having an inner core portion disposed inside the coil and an outer core portion disposed outside the coil. The coil has a winding wound along the outer peripheral surface of the inner core portion. The outer peripheral shape of the coil when viewed from a first direction along the axis of the coil is rectangular. The outer peripheral surface of the coil has a first coil surface and a second coil surface that are along each long side of the outer peripheral shape of the coil and face each other. The first coil surface and the second coil surface are exposed from the outer core portion. At least the outer peripheral region of the inner core portion is made of a molded body of a composite material. The outer peripheral surface of the inner core portion has a plurality of grooves aligned in a direction along the axis of the inner core portion. The winding of each turn of the coil is disposed in each of the plurality of grooves.

[0005] FIG. 1 is a first perspective view showing a reactor of the first embodiment. FIG. 2 is a second perspective view showing the reactor of the first embodiment. FIG. 3 is a cross-sectional view taken along III-III in FIG. 1. FIG. 4 is an enlarged view of region A in FIG. 3. FIG. 5 is a perspective view showing a magnetic core included in the reactor of the first embodiment. FIG. 6 is a perspective view showing a spacer included in the reactor of the first embodiment. FIG. 7 is a first perspective view showing a reactor of the second embodiment. FIG. 8 is a second perspective view showing the reactor of the second embodiment. FIG. 9 is a perspective view showing a magnetic core included in the reactor of the second embodiment. FIG. 10 is a perspective view showing a spacer included in the reactor of the second embodiment. FIG. 11 is an enlarged view showing a groove and a winding in a reactor of the third embodiment. FIG. 12 is an enlarged view showing a groove and a winding in a reactor of the fourth embodiment. FIG. 13 is a configuration diagram schematically showing a power supply system of a hybrid vehicle. FIG. 14 is a circuit diagram showing an example of a power conversion device including a converter.

[0006] [Problem to be Solved by the Present Disclosure] The reactor of Patent Document 1 is manufactured as follows: A pair of winding portions is prepared. Each inner core portion is inserted into each winding portion. Both inner core portions and both outer core portions are fixed together. In order to insert each inner core portion into each winding portion, a gap is provided between the inner peripheral surface of each winding portion and the outer peripheral surface of each inner core portion. The provision of the gap makes it difficult to miniaturize the reactor and also to improve heat dissipation.

[0007] An object of the present disclosure is to provide a reactor that is small and has excellent heat dissipation properties.

[0008] [Advantages of the Present Disclosure] The reactor of the present disclosure is small and has excellent heat dissipation properties.

[0009] <Description of Embodiments of the Present Disclosure> First, embodiments of the present disclosure will be listed and described.

[0010] (1) A reactor according to one embodiment of the present disclosure includes a coil, a magnetic core having an inner core portion disposed inside the coil, and an outer core portion disposed outside the coil. The coil has a winding wound along an outer peripheral surface of the inner core portion. The outer peripheral shape of the coil when viewed from a first direction along the axis of the coil is rectangular. The outer peripheral surface of the coil has a first coil surface and a second coil surface that are along each long side of the outer peripheral shape of the coil and face each other. The first coil surface and the second coil surface are exposed from the outer core portion. At least the outer peripheral region of the inner core portion is made of a molded body of a composite material. The outer peripheral surface of the inner core portion has a plurality of grooves aligned in a direction along the axis of the inner core portion. The winding of each turn of the coil is disposed in each of the plurality of grooves.

[0011] In the reactor (1) described above, each turn of the winding is disposed in each groove on the outer peripheral surface of the inner core portion, so that the gap between the inner core portion and the coil is essentially zero. Therefore, the reactor (1) described above is smaller than reactors with a gap between the inner core portion and the coil. Furthermore, the reactor (1) described above more easily transfers heat from the coil to the magnetic core than reactors with a gap between the inner core portion and the coil. Therefore, the reactor (1) described above can transfer heat from the coil directly to the installation target through the first coil surface or the second coil surface exposed from the outer core portion, and also indirectly to the installation target through the magnetic core by contacting the outer core portion with the installation target. Therefore, the reactor (1) described above has excellent heat dissipation properties. Furthermore, the reactor (1) described above can reduce the height of the coil because the outer peripheral shape of the coil is rectangular. In this specification, the term "the gap is substantially zero" not only refers to the case where the gap is zero, but also includes the case where a gap is provided locally to the extent that it does not impede the heat dissipation effect.

[0012] (2) In the reactor of (1) above, the inner core portion and the outer core portion may be an integral molded body, and the inner core portion and the outer core portion may all be composed of a molded body of the composite material.

[0013] In the reactor of (2) above, the inner core portion and the outer core portion are configured as an integral molded body of a composite material, so that the inner core portion and the outer core portion can be manufactured as a single unit. Therefore, the manufacturing process of the reactor of (2) above can be simplified compared to when the inner core portion and the outer core portion are manufactured separately and then combined together. Therefore, the reactor of (2) above has excellent productivity.

[0014] (3) In the reactor of (2) above, the outer core portion has a first end core portion facing a first end face of the coil and a second end core portion facing a second end face of the coil, and at least one of the first end core portion and the second end core portion may have a gate mark.

[0015] The reactor (3) above is manufactured as follows: The coil is placed in a mold. The raw material for the composite compact is filled into the mold, including the inside of the coil, through one or more gates. The raw material is a fluid material in which soft magnetic powder is dispersed in unsolidified resin. The resin is then solidified.

[0016] When the resin solidifies, an attachment having a portion corresponding to the gate remains connected to the magnetic core. In addition to the portion corresponding to the gate, the attachment may have a portion corresponding to the sprue, and may also have a portion corresponding to the runner. The attachment is removed from the magnetic core. The attachment can be removed, for example, by breaking it off. A gate mark in the form of a protrusion or ridge protruding from the surface remains on the surface of the magnetic core from which the attachment has been removed.

[0017] By providing a gate in the mold facing the molding space of the end core portion, the raw material can be easily poured into the inside of the coil, making it easy to mold the entire magnetic core.

[0018] By manufacturing the reactor of (3) above as described above, it is difficult for the composite material molded body to be disposed between the turns, and for the composite material molded body to protrude from between the turns to the outside of the coil.

[0019] (4) In the reactor of (3) above, the coil may have a first winding portion and a second winding portion arranged in parallel to each other, and the inner core portion may have a first inner core portion arranged inside the first winding portion and a second inner core portion arranged inside the second winding portion.

[0020] In the reactor of (4) above, the windings constituting each turn of the first winding portion are arranged in each of a plurality of grooves in the outer peripheral surface of the first inner core portion, and the windings constituting each turn of the second winding portion are arranged in each of a plurality of grooves in the outer peripheral surface of the second inner core portion. Therefore, the gap between the first winding portion and the first inner core portion is substantially zero, and the gap between the second winding portion and the second inner core portion is substantially zero. Therefore, the reactor of (4) above is compact. Furthermore, the reactor of (4) above has excellent heat dissipation properties because heat from the first winding portion is easily transferred to the first inner core portion and heat from the second winding portion is easily transferred to the second inner core portion.

[0021] (5) In the reactor of (3) above, the number of the coils may be one, and the outer core portion may further include at least one side core portion arranged in parallel with the inner core portion.

[0022] The reactor (5) above is small and has excellent heat dissipation properties.

[0023] (6) A converter according to an embodiment of the present disclosure includes the reactor described in any one of (1) to (5) above.

[0024] The converter has excellent performance due to the inclusion of the reactor.

[0025] (7) A power conversion device according to one embodiment of the present disclosure includes the converter described above in (6).

[0026] The power conversion device has excellent performance because it includes the converter.

[0027] Details of the embodiments of the present disclosure will be described below with reference to the drawings. The same reference numerals in the drawings denote the same components.

[0028] First Embodiment [Reactor] A reactor 1 of the first embodiment will be described with reference to FIGS. 1 to 6. As shown in FIG. 1, the reactor 1 includes a coil 2 and a magnetic core 3. The coil 2 has a first winding 20f and a second winding 20s wound in a spiral shape. The magnetic core 3 has an inner core portion 31 and an outer core portion 32 shown in FIG. 5. The inner core portion 31 shown in FIG. 5 is disposed inside the coil 2 shown in FIGS. 1 and 2. The outer core portion 32 is disposed outside the coil 2 as shown in FIGS. 1 and 2. One feature of the reactor 1 of this embodiment is that it satisfies the following requirements (a) to (c): (a) The outer peripheral shape of the coil 2 when viewed from a first direction along the axis of the coil 2 is rectangular. (b) The outer peripheral surface of the coil 2 has a first coil surface 211 and a second coil surface 212 that are aligned along each long side of the outer peripheral shape of the coil 2 and face each other, and the first coil surface 211 and the second coil surface 212 are exposed from the outer core portion 32. (b) At least the outer peripheral region of the inner core portion 31 is made of a molded body of a composite material. (c) The outer peripheral surface of the inner core portion 31 has a plurality of grooves 31a aligned in a direction along the axis of the inner core portion 31. The first winding 20f and the second winding 20s in each turn of the coil 2 are arranged in each of the plurality of grooves 31a.

[0029] In the following description, the X1 direction, X2 direction, Y1 direction, Y2 direction, Z1 direction, and Z2 direction are defined as follows: The X1 direction is the direction from the second end face of the coil 2 toward the first end face along the axis of the coil 2. The X2 direction is the opposite direction to the X1 direction. The Y1 direction is the direction along the long side of the rectangular outer peripheral shape of the coil 2. The Y2 direction is the opposite direction to the Y1 direction. The Z1 direction is a direction perpendicular to both the X1 direction and the Y1 direction, and is the direction from the second coil surface 212 toward the first coil surface 211 of the coil 2. The Z2 direction is the opposite direction to the Z1 direction.

[0030] [Coil] As shown in FIGS. 1 and 2, the coil 2 of this example has a first winding portion 21f and a second winding portion 21s. The first winding portion 21f has a first winding 20f wound along the outer peripheral surface of the first inner core portion 31f shown in FIG. 5. The second winding portion 21s has a second winding 20s wound along the outer peripheral surface of the second inner core portion 31s shown in FIG. 5. The first winding 20f and the second winding 20s are wound in a spiral shape. In this example, the first winding 20f and the second winding 20s are not connected. That is, the first winding portion 21f and the second winding portion 21s are independent members. Unlike this example, the first winding 20f and the second winding 20s may be a continuous winding. The first winding portion 21f and the second winding portion 21s have the same configuration. The following description will mainly focus on the first winding portion 21f.

[0031] The first winding portion 21f has a rectangular cylindrical shape. The rectangular cylindrical shape of the first winding portion 21f makes it easier to increase the contact area between the first winding portion 21f and a planar installation target compared to when the first winding portion 21f is a circular cylindrical shape with the same cross-sectional area. Therefore, the reactor 1 easily transfers heat from the coil 2 to an installation target (not shown). The installation target is, for example, an air-cooled or water-cooled cooling base. The four corners of the first winding portion 21f are rounded. The outer peripheral shape of the first winding portion 21f is rectangular when viewed from a first direction. The first direction is the X1 direction. The first end surface and second end surface of the first winding portion 21f have a rectangular frame shape. The length of the first winding portion 21f along the Y1 direction is longer than the length along the Z1 direction.

[0032] The outer peripheral surface of the first winding portion 21f has a first coil surface 211 and a second coil surface 212 that face each other. The first coil surface 211 and the second coil surface 212 are aligned along the long sides of the rectangular outer peripheral shape of the first winding portion 21f. The first coil surface 211 and the second coil surface 212 are flat surfaces. In the first winding portion 21f, the length along the Y1 direction is longer than the length along the Z1 direction. Therefore, for example, because the first coil surface 211 and the second coil surface 212 are wide surfaces, heat from the coil 2 can be easily transferred to the installation target by bringing the first coil surface 211 or the second coil surface 212 into contact with the installation target.

[0033] As shown in Figures 1 and 2, the first winding 20f is a series of windings without joints. The first winding 20f is a known winding. In this example, the first winding 20f uses a coated rectangular wire. The conductor wire of the coated rectangular wire is made of copper rectangular wire. The insulating coating of the coated rectangular wire is made of enamel. In this example, the first winding portion 21f is formed by edgewise winding the coated rectangular wire. In the first winding portion 21f, there are substantially no gaps between the turns. Unlike this example, the first winding portion 21f may be formed by flatwise winding the coated rectangular wire. The first winding 20f may be a round wire as described in embodiment 4 with reference to Figure 12. Although not shown, the first winding 20f may be a rectangular wire with a square cross section or a Litz wire.

[0034] As shown in FIGS. 3 and 4 , the first winding 20f is disposed in a groove 31a (described later). A portion of the first winding 20f that forms the inner circumferential surface of the first winding portion 21f is disposed in the groove 31a and is in direct contact with the groove 31a. In the first winding 20f that forms each turn, the portion that forms the inner circumferential surface of the first winding portion 21f is disposed in the groove 31a over its entire length. By disposing the first winding portion 21f in the groove 31a, the gap between the first winding portion 21f and the first inner core portion 31f is substantially zero. This allows the reactor 1 to be miniaturized. Furthermore, the reactor 1 easily transfers heat from the first winding portion 21f to the first inner core portion 31f. Therefore, the reactor 1 not only transfers heat from the coil 2 directly to the installation target through the first coil surface 211 or the second coil surface 212 exposed from the outer core portion 32, but also indirectly transfers heat from the magnetic core 3 to the installation target by bringing the outer core portion 32 into contact with the installation target. Therefore, the reactor 1 has excellent heat dissipation properties.

[0035] In this example, the first end 201 of the first winding 20f is drawn out from a first end surface of the first winding portion 21f in the X1 direction along the X1 direction. The second end 202 of the first winding 20f is drawn out from a second end surface of the first winding portion 21f in the X2 direction along the X2 direction. Specifically, the first end 201 and the second end 202 are drawn out by flatwise bending the first winding 20f in the turns constituting the first and second end surfaces of the first winding portion 21f. More specifically, the first end 201 of the first winding 20f is drawn out so that the surface of the first end 201 of the first winding 20f facing the Z1 direction is substantially flush with the first coil surface 211. The second end 202 of the first winding 20f is drawn out so that the surface of the second end 202 of the first winding 20f facing the Z2 direction is substantially flush with the second coil surface 212. In this specification, "two surfaces are substantially flush" means that the flatness of the two surfaces is 0.4 mm or less. The flatness of the two surfaces may further be 0.2 mm or less, 0.1 mm or less, or 0.05 mm or less. The flatness referred to here complies with JIS B 0621:1984, Definition and Expression of Geometric Deviation.

[0036] In this example, the first end 201 of the second winding 20s is drawn out from a first end surface of the second winding portion 21s in the X1 direction along the X1 direction. The second end 202 of the second winding 20s is drawn out from a second end surface of the second winding portion 21s in the X2 direction along the X2 direction. Specifically, the first end 201 and the second end 202 are drawn out by flatwise bending the second winding 20s in the turns that form the first and second end surfaces of the second winding portion 21s. More specifically, the first end 201 of the second winding 20s is drawn out so that the surface of the first end 201 of the second winding 20s facing the Z2 direction is substantially flush with the second coil surface 212. Furthermore, the second end 202 of the second winding 20s is drawn out so that the surface of the second end 202 of the second winding 20s facing the Z1 direction is substantially flush with the first coil surface 211.

[0037] Although not shown, the insulating coating is stripped from the first end 201 and the second end 202, exposing the conductor wire. Terminal members (not shown) are connected to the exposed conductor wire. An external device (not shown) is connected to the coil 2 via these terminal members. The external device is, for example, a power source that supplies power to the coil 2.

[0038] [Magnetic Core] The magnetic core 3 forms a closed magnetic circuit by an inner core portion 31 and an outer core portion 32 shown in Fig. 5. As shown in Fig. 5, the planar shape of the magnetic core 3 of this example when viewed from the Z1 direction is a rectangular ring shape.

[0039] (Inner core portion) The inner core portion 31 of this example has a first inner core portion 31f and a second inner core portion 31s. The first inner core portion 31f is disposed inside the first winding portion 21f shown in Figures 1 and 2. The second inner core portion 31s is disposed inside the second winding portion 21s shown in Figures 1 and 2. The first inner core portion 31f and the second inner core portion 31s have the same configuration. The following description will mainly focus on the first inner core portion 31f.

[0040] The first inner core portion 31f is aligned along the axis of the first winding portion 21f. In this example, both ends of the portion of the magnetic core 3 that is aligned along the axis of the first winding portion 21f protrude from the first end face and the second end face of the first winding portion 21f to the outside of the first winding portion 21f. The portions that protrude from the first winding portion 21f are also part of the first inner core portion 31f.

[0041] The shape of the first inner core portion 31f corresponds to the shape of the inner peripheral contour of the coil 2. The shape of the first inner core portion 31f is a quadrangular prism. Each of the four corners of the first inner core portion 31f is rounded so as to fit the corresponding four corners of the inner peripheral surface of the coil 2. The outer peripheral shape of the first inner core portion 31f when viewed from the first direction is rectangular. In the first inner core portion 31f, the length along the Y1 direction is longer than the length along the Z1 direction.

[0042] As shown in FIGS. 3 and 4 , the outer peripheral surface of the first inner core portion 31f has a plurality of grooves 31a aligned in a direction along the axis of the first inner core portion 31f. The plurality of grooves 31a are formed according to the inner peripheral surface of the first winding portion 21f when the first inner core portion 31f is formed. Having a plurality of grooves 31a means that the grooves 31a are independent of each other along the X1 direction when focusing on only a certain surface of the outer peripheral surface of the first inner core portion 31f. In this example, the outer peripheral surface of the first inner core portion 31f has one spiral groove provided coaxially with the first inner core portion 31f. Since the spiral groove is continuous when focusing on the entire circumference of the outer peripheral surface of the first inner core portion 31f, the number of spiral grooves is one. In other words, since the spiral groove is continuous when viewed along the longitudinal direction of the groove, the number of spiral grooves is one. In this spiral groove, when focusing on only a certain surface of the outer peripheral surface of the first inner core portion 31f, the groove portions 31a are independent of each other along the X1 direction, and therefore this includes having multiple groove portions 31a.

[0043] As shown in FIG. 4 , the width of each groove 31a is the same as the thickness of the first winding 20f, which is a coated rectangular wire in this embodiment. The width of the groove 31a is a length along a direction perpendicular to both the extension direction of the groove 31a and the depth direction of the groove 31a. Since the width of each groove 31a is substantially the same as the thickness of the first winding 20f, the contact area between the first winding 20f arranged in each groove 31a and the first inner core portion 31f tends to be large. Therefore, heat from the first winding 20f is easily transferred to the first inner core portion 31f. Therefore, the reactor 1 has excellent heat dissipation properties.

[0044] As shown in FIG. 5 , the outer peripheral surface of the first inner core portion 31f may have a plurality of recesses 31b recessed relative to the locations where the plurality of grooves 31a are provided. Specifically, each recess 31b is recessed relative to the bottom of the groove 31a. The recesses 31b are recesses formed in accordance with the guide portions 43 of the spacer 4 described below. The presence of the recesses 31b strengthens the bond between the spacer 4 and the first inner core portion 31f. In this example, the recesses 31b are C-shaped. The recesses 31b are provided on the surface of the first inner core portion 31f facing the Y1 direction or the Y2 direction. In this example, the recesses 31b are provided near the four corners of the first inner core portion 31f when viewed from the Z1 direction. In this example, the number of recesses 31b is four for the first inner core portion 31f. In other words, since four recesses 31b are also provided in the second inner core portion 31s, the total number of recesses 31b provided in the magnetic core 3 is eight. The shape, arrangement location, and number of recesses 31b are not limited to this example and can be selected appropriately.

[0045] At least the outer peripheral region of the first inner core portion 31f is made of a composite material molded body. The outer peripheral region is a region of the first inner core portion 31f extending from the outer peripheral surface facing the inner peripheral surface of the first winding portion 21f to a predetermined depth. The predetermined depth is the same as the depth of the groove portion 31a. The composite material molded body is a molded body formed by dispersing soft magnetic powder in resin. The central region of the first inner core portion 31f may be made of a composite material molded body or a powder compact. The central region of the first inner core portion 31f is a region inside the outer peripheral region. The powder compact is a molded body formed by compression molding soft magnetic powder. In this example, the outer peripheral region and central region of the first inner core portion 31f, i.e., the entire region of the first inner core portion 31f, is made of a composite material molded body.

[0046] The content of soft magnetic powder in the resin of a composite material compact can be easily adjusted. Therefore, the magnetic properties of the composite material compact can be easily adjusted. Furthermore, compared to a powder compact, a composite material compact can be easily formed into a complex shape. The content of soft magnetic powder in the composite material compact is, for example, 20% by volume or more and 80% by volume or less. The content of resin in the composite material compact is, for example, 20% by volume or more and 80% by volume or less. These content percentages are relative to the volume of the composite material compact taken as 100%.

[0047] Compared to a composite material compact, a powder compact can have a higher proportion of soft magnetic powder in the magnetic core 3. Therefore, the powder compact can easily improve its magnetic properties. Magnetic properties include, for example, relative permeability and saturation magnetic flux density. Furthermore, compared to a composite material compact, a powder compact has a smaller amount of resin and a larger amount of soft magnetic powder, resulting in excellent heat dissipation. The soft magnetic powder content in the powder compact is, for example, 85% by volume or more and 99% by volume or less. This content is the ratio relative to the volume of the powder compact taken as 100%.

[0048] The particles constituting the soft magnetic powder are, for example, soft magnetic metal particles, coated particles, or soft magnetic non-metal particles. The coated particles include soft magnetic metal particles and an insulating coating provided on the outer periphery of the soft magnetic metal particles. The soft magnetic metal is, for example, pure iron or an iron-based alloy. The iron-based alloy is, for example, an Fe—Si alloy or an Fe—Ni alloy. The insulating coating is, for example, a phosphate. The soft magnetic non-metal is, for example, a ferrite.

[0049] The resin of the composite material molded body is, for example, a thermosetting resin or a thermoplastic resin. Examples of the thermosetting resin include epoxy resin, phenolic resin, silicone resin, and urethane resin. Examples of the thermoplastic resin include polyphenylene sulfide (PPS) resin, polyamide (PA) resin, liquid crystal polymer (LCP), polyimide resin, and fluororesin. Examples of the PA resin include nylon 6, nylon 66, and nylon 9T.

[0050] The composite material compact may contain a filler, such as a non-magnetic powder of alumina or silica, which contributes to improving heat dissipation and electrical insulation.

[0051] The content of the soft magnetic powder in the composite material compact and the content of the soft magnetic powder in the powder compact are considered to be equivalent to the area ratio of the soft magnetic powder in the cross section of the compact. The content of the soft magnetic powder in the compact is determined as follows. The cross section of the compact is observed with a SEM (scanning electron microscope) to obtain an observation image. The cross section of the compact is any cross section. The magnification of the SEM is 200 times or more and 500 times or less. The number of observation images obtained is 10 or more. The total cross section area is 0.1 cm ２ That's all. One observation image may be acquired per cross section, or multiple observation images may be acquired per cross section. Each acquired observation image is subjected to image processing to extract the particle contours. Image processing is, for example, binarization processing. The area ratio of soft magnetic particles in each observation image is calculated, and the average value of these area ratios is determined. This average value is considered to be the content ratio of soft magnetic powder.

[0052] (Outer Core Portion) The outer core portion 32 in this example has a first end core portion 34f and a second end core portion 34s. The first end core portion 34f faces first end faces of the first winding portion 21f and the second winding portion 21s. Facing means facing. The first end core portion 34f is connected to first ends of the first inner core portion 31f and the second inner core portion 31s. The surface of the first end core portion 34f facing the X2 direction is in direct contact with the surface of the base portion 42a of the first spacer 41f (described below) facing the X1 direction. The second end core portion 34s faces second end faces of the first winding portion 21f and the second winding portion 21s. The second end core portion 34s is connected to second ends of the first inner core portion 31f and the second inner core portion 31s. The surface of the second end core portion 34s facing the X1 direction is in direct contact with the surface of the base portion 42a of the second spacer 41s facing the X2 direction. The first end core portion 34f and the second end core portion 34s have the same configuration. The following description will mainly focus on the first end core portion 34f.

[0053] The first end core portion 34f has a quadrangular prism shape. When viewed from the X1 direction, the outer periphery of the first end core portion 34f has a rectangular shape. The length of the first end core portion 34f along the Y1 direction is longer than the length along the Z1 direction. The length of the first end core portion 34f along the Y1 direction is the same as the lengths of the first winding portion 21f and the second winding portion 21s along the Y1 direction.

[0054] The outer peripheral surface of first end core portion 34f has first core surface 341 and second core surface 342 that face each other. First core surface 341 and second core surface 342 extend along the long sides of the rectangular outer peripheral shape. First core surface 341 is substantially flush with first coil surface 211, and second core surface 342 is substantially flush with second coil surface 212. This reduces the maximum difference in the Z1 direction between first core surface 341 and first coil surface 211 and the maximum difference in the Z2 direction between second core surface 342 and second coil surface 212, allowing both maximum differences to approach 0 (zero).

[0055] As described above, the first end 201 of the first winding 20f, the second end 202 of the second winding 20s, and the first coil surface 211 are substantially flush with each other, and therefore the first end 201 of the first winding 20f, the second end 202 of the second winding 20s, and the first core surface 341 are substantially flush with each other. The second end 202 of the first winding 20f, the first end 201 of the second winding 20s, and the second coil surface 212 are substantially flush with each other, and therefore the second end 202 of the first winding 20f, the first end 201 of the second winding 20s, and the second core surface 342 are substantially flush with each other. Therefore, when the reactor 1 is installed on a planar installation target, both first coil surfaces 211 and both first core surfaces 341 can come into contact with the installation target without the first end 201 of the first winding 20f and the second end 202 of the second winding 20s interfering with the installation target. Alternatively, when the reactor 1 is installed on a planar installation target, both second coil surfaces 212 and both second core surfaces 342 can be brought into contact with the installation target without the second end 202 of the first winding 20f and the first end 201 of the second winding 20s interfering with the installation target. Thus, the reactor 1 can have a larger contact area with the installation target than the reactor X. The reactor X is a reactor in which only the first coil surface 211 is in contact with the installation target, with neither first core surface 341 coming into contact with the installation target.

[0056] In particular, the first core surface 341 and the second core surface 342 are wide surfaces that extend along the long sides of the rectangular outer peripheral shape, allowing for a large contact area with the installation target. Compared to the reactor X, the reactor 1 is more likely to transfer heat from not only the coil 2 but also the first end core portion 34f and the second end core portion 34s to the installation target. Therefore, the reactor 1 is more likely to have improved heat dissipation than the reactor X.

[0057] In the reactor 1, the first core surface 341 and the first coil surface 211 are substantially flush with each other, and the second core surface 342 and the second coil surface 212 are substantially flush with each other. This results in a wide area of ​​both first end faces of the coil 2 that are covered by the first end core portions 34f, and a wide area of ​​both second end faces that are covered by the second end core portions 34s. That is, the area where both first end faces face the first end core portions 34f is wide, and the area where both second end faces face the second end core portions 34s is wide. Therefore, the reactor 1 is more likely to reduce leakage magnetic flux from near both first end faces and near both second end faces than the reactor Y. That is, the reactor 1 is less likely to leak magnetic flux from near both first end faces and near both second end faces than the reactor Y. Reactor Y is a reactor in which portions of both first end faces are not covered by the first end core portions 34f and are exposed from the first end core portions 34f, and portions of both second end faces are not covered by the second end core portions 34s and are exposed from the second end core portions 34s. Reactor 1 can have both first coil surfaces 211 and both first core surfaces 341 in contact with the installation target, or both second coil surfaces 212 and both second core surfaces 342 in contact with the installation target. In other words, reactor 1 has many options for the surface that contacts the installation target. Unlike this example, first core surface 341 does not have to be flush with first coil surface 211, and second core surface 342 does not have to be flush with second coil surface 212.

[0058] At least one of the first end core portion 34 f and the second end core portion 34 s may be formed from a molded body of the composite material described above, or may be formed from the powder compact described above. In this example, both the first end core portion 34 f and the second end core portion 34 s are formed from a molded body of the composite material.

[0059] In this example, the first inner core portion 31f, the second inner core portion 31s, the first end core portion 34f, and the second end core portion 34s are an integral molded body of composite material. The first inner core portion 31f, the second inner core portion 31s, the first end core portion 34f, and the second end core portion 34s can be manufactured collectively. Therefore, the manufacturing process of the reactor 1 can be simplified compared to when the first inner core portion 31f, the second inner core portion 31s, the first end core portion 34f, and the second end core portion 34s are manufactured separately and then assembled. This results in excellent productivity of the reactor 1. At least one of the first end core portion 34f and the second end core portion 34s has a gate mark 35. In this example, both the first end core portion 34f and the second end core portion 34s have the gate mark 35. Unlike this example, only one of the first end core portion 34f and the second end core portion 34s may have the gate mark 35. The gate marks 35 will be described in detail in the manufacturing method section below.

[0060] In this example, the gate marks 35 of the first end core portion 34f are provided on the surface of the first end core portion 34f facing the X1 direction, as shown in FIG. 1 . The gate marks 35 of the first end core portion 34f are provided at the end portion in the Z2 direction. The gate marks 35 of the second end core portion 34s are provided on the surface of the second end core portion 34s facing the X2 direction, as shown in FIG. 2 . The gate marks 35 of the second end core portion 34s are provided at the end portion in the Z2 direction. The shape and position of each gate mark 35 are not particularly important. The number of gate marks 35 of each of the first end core portion 34f and the second end core portion 34s may be two or more, i.e., the total number of gate marks 35 provided on the magnetic core 3 may be four or more.

[0061] [Spacer] The reactor 1 of this example further includes a spacer 4. The spacer 4 positions the first winding portion 21f and the second winding portion 21s relative to each other. As shown in FIG. 6 , the spacer 4 of this example is composed of two members, a first spacer 41f and a second spacer 41s. The first spacer 41f is disposed between first end faces of the first winding portion 21f and the second winding portion 21s and the first end core portion 34f. The second spacer 41s is disposed between second end faces of the first winding portion 21f and the second winding portion 21s and the second end core portion 34s. The first spacer 41f and the second spacer 41s have the same configuration. The following description will mainly focus on the first spacer 41f.

[0062] The first spacer 41f includes a base 42a and a plurality of guide portions 43. The base 42a is the main portion of the first spacer 41f and is configured in a B-shape when viewed from the X1 direction. The outer periphery of the base 42a when viewed from the X1 direction is rectangular. The length of the base 42a along the Y1 direction is longer than the length along the Z1 direction.

[0063] The outer peripheral surface of the base 42a has a first surface 421 and a second surface 422 that face each other. The first surface 421 and the second surface 422 extend along the long sides of the rectangular outer peripheral shape of the base 42a. The first surface 421 and the second surface 422 are flat surfaces. The first surface 421 is substantially flush with both first coil surfaces 211 and the first core surface 341. The second surface 422 is substantially flush with both second coil surfaces 212 and the second core surface 342.

[0064] The base portion 42a has two through holes 44. Both through holes 44 penetrate the base portion 42a so as to connect a surface facing the X1 direction with a surface facing the X2 direction. The first inner core portion 31f or the second inner core portion 31s passes through each through hole 44. When viewed from the X1 direction, each through hole 44 has a rectangular shape except for a portion where a guide portion 43 (described later) is provided.

[0065] The base 42a has a first notch 451 and a second notch 452. The first notch 451 is provided at the Y1-direction end of the surface of the base 42a facing the Z1 direction. The first end 201 of the first winding 20f is fitted into the first notch 451. The size and shape of the first notch 451 correspond to the cross-sectional dimensions of the first winding 20f. The second notch 452 is provided at the Y2-direction end of the surface of the base 42a facing the Z2 direction. The first end 201 of the second winding 20s is fitted into the second notch 452. The size and shape of the second notch 452 correspond to the cross-sectional dimensions of the second winding 20s.

[0066] Each guide portion 43 is a portion for positioning the coil 2 relative to the spacer 4 by fitting the first winding portion 21f and the second winding portion 21s onto the outer periphery of the guide portion 43. The guide portion 43 protrudes in the X2 direction from the surface of the base portion 42a facing the X2 direction and extends to a part of the inner periphery of the through hole 44. There are two guide portions 43 for each through hole 44, for a total of four guide portions 43. In this example, the guide portions 43 are C-shaped. The C-shaped guide portions 43 are provided at both ends of each through hole 44 so that their openings face each other.

[0067] The first spacer 41f is made of an electrically insulating material. The first spacer 41f maintains electrical insulation between the first winding portion 21f and the second winding portion 21s and the outer core portion 32. Examples of electrically insulating materials include PPS resin, polytetrafluoroethylene (PTFE) resin, LCP, PA resin, polybutylene terephthalate (PBT) resin, and acrylonitrile butadiene styrene (ABS) resin. Alternatively, the material of the first spacer 41f may be a thermosetting resin such as unsaturated polyester resin, epoxy resin, urethane resin, or silicone resin. These resins may contain a filler. The filler may be, for example, a non-magnetic powder such as alumina or silica.

[0068] [Manufacturing Method] The reactor 1 of this example is manufactured by carrying out the following steps α to γ.

[0069] In step α, an assembly of the coil 2 and the spacer 4 is placed in a mold.

[0070] In step β, the raw material for the composite compact is filled into the mold, including the interior of the coil 2, through the gate. The raw material is a fluid material in which soft magnetic powder is dispersed in unsolidified resin. In this example, two gates are provided. The first and second gates are positioned so that when the raw material is filled through the first and second gates, the flow of the filled raw material into the interior of the coil 2 can compress the coil 2 so that the gaps between each turn of the coil 2 become narrower. In this case, the filled raw material is less likely to pass between the turns and leak from the interior of the first winding portion 21f and the second winding portion 21s to the exterior. The first gate is provided at a location facing the first end face of the coil 2, and the second gate is provided at a location facing the second end face of the coil 2. More specifically, the first and second gates are positioned corresponding to the first end core portion 34f and the second end core portion 34s, respectively. That is, the raw material charged from the first gate is charged into the first winding portion 21f and the second winding portion 21s from openings at the first ends of the first winding portion 21f and the second winding portion 21s. The raw material charged from the second gate is charged into the first winding portion 21f and the second winding portion 21s from openings at the second ends of the first winding portion 21f and the second winding portion 21s. The raw material charged from the first gate and the raw material charged from the second gate compress the coil 2 so that the distance between turns becomes narrower.

[0071] When the raw material is filled from each gate in step β, the first spacer 41f and the second spacer 41s are pressed toward each other by the flow of the filled raw material into the inside of the coil 2. This pressing force allows the first spacer 41f and the second spacer 41s to compress the coil 2 so that the spaces between the turns of the coil 2 become narrower. Therefore, the filled raw material does not pass between the turns and leak from the inside of the first winding portion 21f and the second winding portion 21s to the outside.

[0072] In step γ, the resin is solidified. Once the resin has solidified, an attached portion having a portion corresponding to the gate remains connected to the magnetic core 3. In addition to the portion corresponding to the gate, the attached portion may also have a portion corresponding to the sprue and / or a portion corresponding to the runner. The attached portion is then removed from the magnetic core 3. The attached portion can be removed, for example, by breaking it off. After the attached portion is removed, a gate mark 35, which is a protrusion or ridge protruding from the surface of the magnetic core 3—in this example, the surface of both the first end core portion 34f and the second end core portion 34s—remains. The presence of the gate mark 35 on both the first end core portion 34f and the second end core portion 34s, as in this example, means that the coil 2 is compressed so that the distance between turns is narrowed, as described above. Therefore, the raw material is less likely to leak from the inside to the outside of the coil 2 through the gaps between the turns.

[0073] 7 to 10 , a reactor 1 of a second embodiment will be described. The reactor 1 of the second embodiment differs from the reactor 1 of the first embodiment in that the number of coils 2 is one and that the planar shape of the magnetic core 3 as viewed from the Z1 direction is θ-shaped. The following description will focus on the differences from the first embodiment. Description of the same configuration and effects as those of the first embodiment will be omitted.

[0074] [Coil] The coil 2 has a winding 20 wound around the outer circumferential surface of the inner core portion 31. The number of coils 2 is one. The reactor 1 of this example has fewer parts than when the reactor 1 has multiple coils 2. Therefore, the reactor 1 of this example has excellent productivity.

[0075] The first end 201 of the winding 20 is drawn out in the Y2 direction from the turn that constitutes the first end surface of the coil 2 along the Y2 direction. The second end 202 of the winding 20 is drawn out in the Y2 direction from the turn that constitutes the second end surface of the coil 2 along the Y2 direction. Specifically, the first end 201 of the winding 20 is drawn out so that the surface facing the Z2 direction is substantially flush with the second coil surface 212. The second end 202 of the winding 20 is drawn out so that the surface facing the Z1 direction is substantially flush with the first coil surface 211.

[0076] The second end 202 of the winding 20 is disposed in a groove 335, which will be described later. The second end 202 of the winding 20 is in direct contact with the inner surface of the groove 335, except for the surface of the second end 202 of the winding 20 facing the Z1 direction. The second end 202 of the winding 20 has a surface that is substantially flush with the first coil surface 211 and a region that is in direct contact with the inner surface of the groove 335. The first end 201 of the winding 20 is disposed in a groove (not shown). The configuration of the groove in which the first end 201 is disposed is the same as that of the groove 335. The first end 201 of the winding 20 is in direct contact with the inner surface of the groove, except for the surface of the first end 201 of the winding 20 facing the Z2 direction. In other words, the first end 201 of the winding 20 has a surface that is substantially flush with the second coil surface 212 and a region that is in direct contact with the inner surface of the groove.

[0077] [Magnetic Core] (Outer Core Portion) The outer core portion 32 in this example has a first end core portion 34f, a second end core portion 34s, a first side core portion 33f, and a second side core portion 33s. The first side core portion 33f and the second side core portion 33s are arranged on the outer periphery of the coil 2 so as to sandwich the inner core portion 31 shown in FIG. 9 . That is, as shown in FIG. 9 , the first side core portion 33f, the inner core portion 31, and the second side core portion 33s are arranged in parallel in this order along the Y2 direction. First ends of the first side core portion 33f and the second side core portion 33s are connected to the first end core portion 34f, and second ends of the first side core portion 33f and the second side core portion 33s are connected to the second end core portion 34s. The surface of the first side core portion 33f facing the Y2 direction is in direct contact with the surface of a first protrusion 42f of a first spacer 41f (described later) facing the Y1 direction. The surface of the second side core portion 33s facing the Y1 direction is in direct contact with the surface of the second protrusion 42s of the first spacer 41f facing the Y2 direction. The first side core portion 33f and the second side core portion 33s have the same configuration. The following description will mainly focus on the second side core portion 33s.

[0078] The second side core portion 33s has a quadrangular prism shape. When viewed from the X1 direction, the outer periphery of the second side core portion 33s has a rectangular shape. Although the four corners of the second side core portion 33s are angular, they may be rounded. In this example, the length of the second side core portion 33s along the Y1 direction is shorter than the length along the Z1 direction. Unlike this example, the length of the second side core portion 33s along the Y1 direction may be the same as the length along the Z1 direction, or the length along the Y1 direction may be longer than the length along the Z1 direction.

[0079] The outer peripheral surface of the second side core portion 33s has a first core surface 331 and a second core surface 332 that face each other. The first core surface 331 and the second core surface 332 extend along the shorter sides of the rectangular outer peripheral shape. The first core surface 331 is substantially flush with the first coil surface 211 and both first core surfaces 341. The second core surface 332 is substantially flush with the second coil surface 212 and both second core surfaces 342. This reduces the maximum difference in the Z1 direction between the first coil surface 211 and both first core surfaces 341 and the first core surface 331, and the maximum difference in the Z2 direction between the second coil surface 212 and both second core surfaces 342 and the second core surface 332, allowing both maximum differences to approach zero. The reactor 1 has excellent heat dissipation properties because both first core surfaces 331 or both second core surfaces 332 are in contact with the installation object.

[0080] Unlike this example, the first core surface 331 may not be flush with the first coil surface 211 , and the second core surface 332 may not be flush with the second coil surface 212 .

[0081] As shown in FIG. 9 , the second side core portion 33s has grooves 335 provided in the first core surface 331. The second side core portion 33s also has grooves provided in the second core surface 332, although these are not shown. The grooves 335 in the first core surface 331 and the grooves (not shown) in the second core surface 332 are grooves formed in accordance with the second end 202 and first end 201 of the winding 20 when the second side core portion 33s is formed. The second end 202 of the winding 20 is disposed in the grooves 335 in the first core surface 331. The first end 201 of the winding 20 is disposed in the grooves (not shown) in the second core surface 332. The widths of the grooves 335 in the first core surface 331 and the grooves (not shown) in the second core surface 332 are the same as the thickness of the winding 20, which is a coated rectangular wire. The depth of the grooves 335 in the first core surface 331 and the grooves (not shown) in the second core surface 332 is the same as the width of the coated rectangular wire 20. The first side core portion 33f of this example does not have the grooves 335 described in the second side core portion 33s.

[0082] The inner core portion 31, the first end core portion 34f, the second end core portion 34s, the first side core portion 33f, and the second side core portion 33s are an integral molded body made of a composite material.

[0083] [Spacer] The planar shape of the first spacer 41f and the second spacer 41s of this example, as viewed from the Z1 direction, is U-shaped as shown in FIG. 10. The first spacer 41f and the second spacer 41s of this example further include a first protrusion 42f and a second protrusion 42s in addition to the base 42a and the guide portion 43. The first spacer 41f and the second spacer 41s have the same configuration. The following description will mainly focus on the second spacer 41s.

[0084] The first protrusion 42f and the second protrusion 42s of the second spacer 41s extend in the X1 direction from the Y1-direction end and the Y2-direction end of the base 42a. The first protrusion 42f is disposed between the coil 2 and the first side core portion 33f. The second protrusion 42s is disposed between the coil 2 and the second side core portion 33s. The first protrusion 42f and the second protrusion 42s are C-shaped. The C-shaped first protrusion 42f and the C-shaped second protrusion 42s are provided at both ends of the base 42a with their openings facing each other.

[0085] The first protrusion 42f and the second protrusion 42s have a first surface 423 and a second surface 424 that face each other. The first surface 423 and the second surface 424 are flat surfaces. The first surface 423 is substantially flush with the first surface 421. The second surface 424 is substantially flush with the second surface 422.

[0086] The second protrusion 42s of the second spacer 41s has a groove 46. The groove 46 leads out the second end 202. The groove 46 is provided on the surface of the second protrusion 42s facing the Z1 direction. The groove 46 is provided at the end of the second protrusion 42s facing the X2 direction. The width of the groove 46 is greater than the thickness of the winding wire 20, which is a coated rectangular wire. The depth of the groove 46 is the same as the width of the winding wire 20, which is a coated rectangular wire. The second protrusion 42s of the first spacer 41f has a groove (not shown). The groove leads out the first end 201. The groove (not shown) is provided on the surface of the second protrusion 42s facing the Z2 direction. The groove (not shown) is provided at the end of the second protrusion 42s facing the X1 direction. The width and depth of the groove (not shown) are the same as the width and depth of the groove 46.

[0087] Third Embodiment As shown in FIG. 11 , in a reactor 1 according to a third embodiment, the coil 2 may have an insulating layer 25 formed along the inner circumferential surface of the coil 2. The insulating layer 25 tends to improve electrical insulation between the coil 2 and the inner core portion 31. The insulating layer 25 is formed, for example, from the resin forming the composite material molded body described above or the same resin as the resin forming the spacer 4. The insulating layer 25 is disposed in the groove portion 31 a of the inner core portion 31. The thickness of the insulating layer 25 is, for example, 500 μm or less, preferably 300 μm or less, and particularly 100 μm or less. The insulating layer 25 is formed on the inner circumferential surface of the coil 2 before placing the coil 2 in a mold. The insulating layer 25 can be formed, for example, by applying an insulating material or attaching an insulating sheet.

[0088] 12 , in a reactor 1 according to a fourth embodiment, the first winding 20f may be a round wire, and the contour of each groove 31a may be U-shaped. The width and depth of each groove 31a are the same as the diameter of the winding 20.

[0089] Fifth Embodiment Converter / Power Conversion Apparatus The reactor 1 according to any one of the first to fourth embodiments can be used in applications that satisfy the following current-carrying conditions. The maximum DC current is, for example, about 100 A or more and 1000 A or less. The average voltage is, for example, about 100 V or more and 1000 V or less. The operating frequency is, for example, about 5 kHz or more and 100 kHz or less. The reactor 1 according to any one of the first to fourth embodiments can be used as a component of a converter mounted on a vehicle 1200, typically an electric vehicle, a hybrid vehicle, or a fuel cell vehicle, or as a component of a power conversion apparatus that includes this converter.

[0090] As shown in Fig. 13 , vehicle 1200 includes a main battery 1210, a power conversion device 1100 connected to main battery 1210, and a motor 1220 that is driven by power supplied from main battery 1210 and used for traveling. Motor 1220 is typically a three-phase AC motor. Motor 1220 drives wheels 1250 during traveling and functions as a generator during regeneration. In the case of a hybrid vehicle, vehicle 1200 includes an engine 1300 in addition to motor 1220. Although Fig. 13 shows an inlet as a charging point for vehicle 1200, a plug may also be provided.

[0091] The power conversion device 1100 includes a converter 1110 and an inverter 1120. The converter 1110 is connected to a main battery 1210. The inverter 1120 is connected to the converter 1110. The inverter 1120 converts DC to AC and vice versa. The converter 1110 shown in this example boosts the input voltage of the main battery 1210, which is approximately 200 V to 300 V, to approximately 400 V to 700 V during vehicle 1200 travel, and supplies the voltage to the inverter 1120. During regeneration, the converter 1110 reduces the input voltage output from the motor 1220 via the inverter 1120 to a DC voltage suitable for the main battery 1210, and charges the main battery 1210. The input voltage is a DC voltage. During vehicle 1200 travel, the inverter 1120 converts the DC voltage boosted by the converter 1110 into a predetermined AC voltage and supplies the AC voltage to the motor 1220. During regeneration, inverter 1120 converts AC output from motor 1220 into DC and outputs it to converter 1110 .

[0092] As shown in FIG. 14 , the converter 1110 includes a plurality of switching elements 1111, a drive circuit 1112 that controls the operation of the switching elements 1111, and a reactor 1115. The converter 1110 converts the input voltage by repeatedly switching the elements on and off. The conversion of the input voltage here refers to boosting and bucking the voltage. The switching elements 1111 are power devices such as field-effect transistors and insulated gate bipolar transistors. The reactor 1115 utilizes the properties of a coil that hinders changes in current flowing through a circuit, and has the function of smoothing changes when the current increases or decreases due to switching operations. The reactor 1115 includes the reactor 1 of any one of the first to fourth embodiments. The power conversion device 1100 and the converter 1110 that include the reactor 1 are expected to have improved heat dissipation.

[0093] In addition to converter 1110, vehicle 1200 also includes a power supply converter 1150 and an auxiliary power supply converter 1160. Power supply converter 1150 is connected to main battery 1210. Auxiliary power supply converter 1160 is connected to main battery 1210 and sub-battery 1230, which serves as a power source for auxiliary equipment 1240. Auxiliary power supply converter 1160 converts the high voltage of main battery 1210 to a low voltage. Converter 1110 typically performs DC-DC conversion, while power supply converter 1150 and auxiliary power supply converter 1160 perform AC-DC conversion. Some power supply converters 1150 perform DC-DC conversion. The reactors of power supply converter 1150 and auxiliary power supply converter 1160 may have the same configuration as reactor 1 of any of embodiments 1 to 4, but may be reactors whose size, shape, etc. are appropriately modified. Furthermore, the reactor 1 according to any one of the first to fourth embodiments can also be used in a converter that converts input power, such as a converter that only boosts voltage or a converter that only bucks voltage.

[0094] The present invention is not limited to these examples, but is defined by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0095] For example, the number of coils may be one, and the planar shape of the magnetic core may be a rectangular ring. The magnetic core has an inner core portion, a side core portion, a first end core portion, and a second end core portion. The coil has a winding wound along the outer circumferential surface of the inner core portion. The side core portion is arranged in parallel with the inner core portion. The side core portion is arranged on the outer periphery of the coil. In other words, no coil is wound around the outer circumferential surface of the side core portion. The first end core portion is connected to first ends of the inner core portion and the side core portion. The second end core portion is connected to second ends of the inner core portion and the side core portion.

[0096] Alternatively, the magnetic core may have a circular planar shape, for example.

[0097] REFERENCE SIGNS LIST 1 Reactor 2 Coil 20 Winding, 20f First winding, 20s Second winding 201 First end, 202 Second end 21f First winding portion, 21s Second winding portion 211 First coil surface, 212 Second coil surface, 25 Insulating layer 3 Magnetic core 31 Inner core portion, 31f First inner core portion, 31s Second inner core portion 31a Groove portion, 31b Recessed portion 32 Outer core portion, 33f First side core portion, 33s Second side core portion 331 First core surface, 332 Second core surface, 335 Groove portion 34f First end core portion, 34s ​​Second end core portion 341 First core surface, 342 Second core surface, 35 Gate mark 4 Spacer 41f First spacer, 41s Second spacer, 42a Base portion 421 First surface, 422 Second surface, 42f First protrusion, 42s Second protrusion 423 First surface, 424 Second surface, 43 Guide portion, 44 Through hole 451 First notch, 452 Second notch, 46 Groove portion 1100 Power conversion device, 1110 Converter 1111 Switching element, 1112 Drive circuit 1115 Reactor, 1120 Inverter 1150 Converter for power supply device, 1160 Converter for auxiliary power supply 1200 Vehicle, 1210 Main battery, 1220 Motor 1230 Sub-battery, 1240 Auxiliary equipment 1250 Wheels, 1300 Engine

Claims

1. A reactor comprising: a coil; and a magnetic core having an inner core portion arranged inside the coil and an outer core portion arranged outside the coil, wherein the coil has a winding wound along an outer peripheral surface of the inner core portion, the outer peripheral shape of the coil when viewed from a first direction along the axis of the coil is rectangular, the outer peripheral surface of the coil has a first coil surface and a second coil surface that are along each of the long sides of the outer peripheral shape of the coil and face each other, the first coil surface and the second coil surface are exposed from the outer core portion, at least the outer peripheral region of the inner core portion is composed of a molded body of a composite material, the outer peripheral surface of the inner core portion has a plurality of grooves arranged in a direction along the axis of the inner core portion, and the winding of each turn of the coil is arranged in each of the plurality of grooves.

2. The reactor according to claim 1, wherein the inner core portion and the outer core portion are an integral molded body, and the inner core portion and the outer core portion are entirely made of the composite material molded body.

3. The reactor as described in claim 2, wherein the outer core portion has a first end core portion facing a first end face of the coil and a second end core portion facing a second end face of the coil, and at least one of the first end core portion and the second end core portion has a gate mark.

4. A reactor as described in claim 3, wherein the coil has a first winding portion and a second winding portion arranged in parallel to each other, and the inner core portion has a first inner core portion arranged inside the first winding portion and a second inner core portion arranged inside the second winding portion.

5. The reactor according to claim 3, wherein the number of the coils is one, and the outer core portion further comprises at least one side core portion arranged in parallel with the inner core portion.

6. A converter comprising a reactor according to any one of claims 1 to 5.

7. A power conversion device comprising the converter according to claim 6.

Images