WO2024005094A1 - Reactor, magnetic core, converter, and electric power conversion device - Google Patents

Abstract

This reactor comprises a magnetic core that has a core portion that is configured as a rectangular column, and a coil that has windings that are arranged at an outer periphery of the core portion. The core portion includes a first corner portion that has a plurality of first recesses that are lined up in a direction along the axis of the core portion, the windings are constituted by winding wires that are wound in a plurality of turns so as to follow the outer peripheral surfaces of the core portion, the winding wire of each of the plurality of turns having one first linear portion that crosses without being orthogonal to a direction along the axis of the windings, a second linear portion that is orthogonal to the direction along the axis of the windings, and a first bent portion that connects the first linear portion and the second linear portion, the first bent portions in the plurality of turns being disposed in the plurality of first recesses.

Description

Reactors, magnetic cores, converters, and power conversion equipment

The present disclosure relates to a reactor, a magnetic core, a converter, and a power conversion device.
This application claims priority based on Japanese Patent Application No. 2022-105128 filed on June 29, 2022, and incorporates all the contents described in the Japanese application.

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

JP2013-219318A

The reactor of the present disclosure is
a magnetic core having a core portion configured in a prismatic shape;
a coil having a winding part arranged around the outer periphery of the core part,
The core portion includes a first corner portion having a plurality of first recesses arranged in a direction along the axis of the core portion,
The winding part is composed of a winding wire wound in a plurality of turns along the outer peripheral surface of the core part,
The winding of each of the plurality of turns is
one first straight portion that intersects the direction along the axis of the winding portion without being perpendicular to it;
a second linear portion perpendicular to the direction along the axis of the winding portion;
a first bent part connecting the first straight part and the second straight part,
The first bent portion in each of the plurality of turns is arranged in each of the plurality of first recesses.

The magnetic core of the present disclosure includes:
It has a prismatic core,
The core portion includes a first corner portion having a plurality of first recesses arranged in a direction along the axis of the core portion.

The converter of the present disclosure includes the reactor of the present disclosure.

The power conversion device of the present disclosure includes the converter of the present disclosure.

FIG. 1 is a schematic perspective view showing a reactor of Embodiment 1. FIG. 2 is a schematic exploded perspective view showing the reactor of the first embodiment. FIG. 3 is a sectional view taken along line III--III in FIG. FIG. 4 is an enlarged view of area A in FIG. FIG. 5 is an enlarged view of the VV cross section in FIG. 2. FIG. 6 is a schematic perspective view showing the turns of the winding portion in the reactor of Embodiment 1. FIG. 7 is an enlarged view showing grooves and windings in the reactor of Embodiment 2. FIG. 8 is an enlarged view showing grooves and windings in the reactor of Embodiment 3. FIG. 9 is an enlarged view showing grooves and windings in the reactor of Embodiment 4. FIG. 10 is an enlarged view showing another example of the groove and the winding in the reactor of Embodiment 4. FIG. 11 is a configuration diagram schematically showing a power supply system of a hybrid vehicle. FIG. 12 is a circuit diagram showing an example of a power conversion device including a converter.

[Problems that this disclosure seeks to solve]
The reactor of Patent Document 1 is manufactured as follows. Prepare a pair of winding parts. Insert each inner core portion inside each winding portion. Both inner cores and both outer core parts are fixed. In order to insert each inner core part inside each winding part, a gap is provided between the inner peripheral surface of each winding part and the outer peripheral surface of each inner core part. The gap makes it difficult to improve the heat dissipation of the inner core.

One of the purposes of the present disclosure is to provide a reactor that can easily improve heat dissipation. One of the objects of the present disclosure is to provide a magnetic core that can construct a reactor that easily improves heat dissipation. One object of the present disclosure is to provide a converter including the reactor, and a power conversion device including the converter.

[Effects of this disclosure]
The reactor of the present disclosure can easily improve heat dissipation. The magnetic core of the present disclosure makes it easy to construct a reactor that can easily improve heat dissipation. The converter of the present disclosure and the power conversion device of the present disclosure have excellent heat dissipation properties.

<<Description of embodiments of the present disclosure>>
In order to improve heat dissipation, the present inventors considered winding the windings constituting the coil directly around the core, thereby bringing the windings into contact with the core and transmitting the heat of the windings to the core. . As a result, it was found that a gap was formed between the winding wire and the core portion at a specific bent portion of the winding wire in each turn, and the contact area between the specific bent portion and the core portion was reduced. The present inventors have completed the present invention as a result of intensive studies on increasing the contact area between a specific bent portion and the core portion. First, embodiments of the present disclosure will be listed and described.

(1) A reactor according to one embodiment of the present disclosure includes:
a magnetic core having a core portion configured in a prismatic shape;
a coil having a winding part arranged around the outer periphery of the core part,
The core portion includes a first corner portion having a plurality of first recesses arranged in a direction along the axis of the core portion,
The winding part is composed of a winding wire wound in a plurality of turns along the outer peripheral surface of the core part,
The winding of each of the plurality of turns is
one first straight portion that intersects the direction along the axis of the winding portion without being perpendicular to it;
a second linear portion perpendicular to the direction along the axis of the winding portion;
a first bent part connecting the first straight part and the second straight part,
The first bent portion in each of the plurality of turns is arranged in each of the plurality of first recesses.

The configuration (1) above can easily improve heat dissipation compared to conventional reactors. In the configuration (1) above, the winding of each turn is along the outer circumferential surface of the core, which tends to increase the contact area between the winding of each turn and the core compared to conventional reactors. . Therefore, in the configuration (1) above, compared to the conventional reactor, it is easier to transfer the heat of the winding to the core part in addition to the reactor installation target.

The configuration (1) above can easily improve heat dissipation compared to the reactor of the following reference example. The reactor of the reference example differs from the configuration (1) above in that a winding wire is wound around a core portion that does not have a first recess. The first bending portion of the winding is a location where the winding is bent and shifted in the direction along the axis of the winding portion. Therefore, the first bent portion is twisted. In the reactor of the reference example, a gap is likely to be formed between the corner portion that does not have the first recess and the first bent portion. Therefore, the contact area between the core portion and the first bent portion in the reactor of the reference example tends to be small. On the other hand, in the configuration (1) above, since the first bent portion is disposed in the first recess, the contact area between the core portion and the first bent portion tends to be large. Therefore, the configuration (1) above can easily transmit the heat of the winding to the core compared to the reactor of the reference example.

(2) In the reactor of (1) above,
The core portion has a second corner portion adjacent to the first corner portion in a direction around the axis of the core portion,
The second corner portion has a plurality of second recesses arranged in a direction along the axis of the core portion,
The winding of each of the plurality of turns has a second bent part connected to the first straight part,
The second bent portion in each of the plurality of turns may be arranged in each of the plurality of second recesses.

The configuration (2) above can easily improve heat dissipation compared to the case where only the first recess is provided. The second bent portion is also twisted. In the configuration (2) above, the contact area between the core portion and the second bent portion tends to be large. Therefore, the configuration (2) above easily transfers the heat of the winding to the core portion.

(3) In the reactor of (2) above,
The winding wire is a flat wire,
The cross-sectional shape of each of the plurality of first recesses and each of the plurality of second recesses cut along the axis of the core portion may be triangular.

In the configuration (3) above, since the winding can be easily arranged in the first recess and the second recess, the contact area between the core part and the winding can easily become large. Therefore, the configuration (3) above easily transfers the heat of the winding to the core portion.

(4) In the reactor of (3) above,
The winding portion may be formed by winding the rectangular wire flatwise.

The configuration (4) above makes it easier to bend the rectangular wire compared to the configuration (5) described later, so it is easier to manufacture the first winding part and the second winding part.

(5) In the reactor of (3) above,
The winding portion may be formed by edgewise winding the flat wire.

When the length of the winding part in the direction along the axis is constant, the configuration (5) above makes it easier to increase the number of turns in the winding part compared to the configuration (4) above. When the number of turns of the winding part is constant, the configuration (5) above makes it easier to shorten the length of the winding part in the direction along the axis, compared to the configuration (4) above. Therefore, the configuration (5) above is easier to downsize than the configuration (4) above.

(6) In any of the reactors from (1) to (5) above,
The core portion has a quadrangular prism shape,
The winding portion may have a rectangular cylindrical shape.

The configuration (6) above is easy to manufacture because the winding wire can be easily wound along the outer peripheral surface of the core portion during the manufacturing process. The configuration (6) above makes it easier to increase the contact area between the winding part and the object on which the reactor is installed, compared to a case where the winding part has a circular cylindrical shape with the same cross-sectional area. Therefore, the configuration (6) above easily transfers the heat of the winding portion to the installation target. Moreover, the configuration (6) above makes it easy to stably install the winding portion as the installation target.

(7) In any of the reactors from (1) to (6) above,
The core portion is
A core body mainly made of magnetic material,
an insulating part provided along the outer peripheral surface of the core main body part,
The plurality of first recesses may be provided in the insulating section.

In the configuration (7) above, the insulation between the core body and the winding part can be easily increased by the insulating part, compared to the case where the core part does not include an insulating part and is composed only of the core body part. .

(8) The magnetic core according to one embodiment of the present disclosure includes:
It has a prismatic core,
The core portion includes a first corner portion having a plurality of first recesses arranged in a direction along the axis of the core portion.

The configuration (8) above makes it easy to construct a reactor that can easily improve heat dissipation for the reason explained in the configuration (1) above.

(9) In the magnetic core of (8) above,
The core portion has a second corner portion adjacent to the first corner portion in a direction around the axis of the core portion,
The second corner portion may have a plurality of second recesses arranged in a direction along the axis of the core portion.

For the reason explained in the configuration (2) above, the configuration (9) above makes it easier to construct a reactor that can easily improve heat dissipation compared to the case where only the first recess is provided.

(10) A converter according to an embodiment of the present disclosure includes:
The reactor according to any one of the above (1) to (7) is provided.

Since the converter includes the reactor, it has excellent heat dissipation.

(11) A power conversion device according to an embodiment of the present disclosure includes:
The converter described in (10) above is provided.

Since the power conversion device includes the converter, it has excellent heat dissipation.

<<Details of embodiments of the present disclosure>>
Details of embodiments of the present disclosure will be described below with reference to the drawings. The same reference numerals in the figures indicate the same names. The sizes of members shown in each drawing are expressed for the purpose of clarifying the explanation, and do not necessarily represent actual dimensional relationships.

《Embodiment 1》
[Reactor]
A reactor 1 according to a first embodiment will be described with reference to FIGS. 1 to 6. The reactor 1 includes a coil 2 and a magnetic core 3. As shown in FIG. 2, the magnetic core 3 has a core portion 30. As shown in FIG. The core portion 30 has a prismatic shape. The coil 2 has a winding portion 20 . The winding portion 20 is arranged around the outer periphery of the core portion 30. One of the features of the reactor 1 of this embodiment is that it satisfies the following requirements (A) to (C).
(A) The core portion 30 includes a first corner portion 311. The first corner portion 311 has a plurality of first recesses 312 arranged in a direction along the axis of the core portion 30, as shown in FIGS. 2 to 4.
(B) The winding portion 20 is composed of a wire 21 wound in a plurality of turns along the outer peripheral surface of the core portion 30.
(C) The first bent portion 213 of each turn of the winding 21 shown in FIG. 6 is arranged in each first recess 312 shown in FIGS. 3 and 4.

[Magnetic core]
The magnetic core 3 of this embodiment shown in FIG. 2 includes a first middle core part 31f, a second middle core part 31s, a first end core part 33f, and a second end core part 33s. The core section 30 of this embodiment constitutes each of a first middle core section 31f and a second middle core section 31s. Unlike the fourth embodiment, each of the core portions 30 of this embodiment, that is, the first middle core portion 31f and the second middle core portion 31s, does not include an insulating portion 30b, which will be described later with reference to FIGS. 9 and 10. , a core main body portion 30a mainly made of magnetic material. The core body portion 30a is made of a molded body or a laminate, which will be described later. Each of the first end core part 33f and the second end core part 33s is formed of a molded body or a laminate that is independent of the first middle core part 31f and the second middle core part 31s.

The first middle core part 31f, the second middle core part 31s, the first end core part 33f, and the second end core part 33s are combined in an annular shape. The first end surface of the first middle core section 31f and the inner end surface of the first end core section 33f face each other. The second end surface of the first middle core section 31f and the inner end surface of the second end core section 33s face each other. The first end surface of the second middle core section 31s and the inner end surface of the first end core section 33f face each other. The second end surface of the second middle core section 31s and the inner end surface of the first end core section 33f face each other. Between the first middle core part 31f and the first end core part 33f, between the first middle core part 31f and the second end core part 33s, between the second middle core part 31s and the first end core part 33f, the second middle core part 31s A gap material, which will be described later, may be placed between the end core portion 33s and the second end core portion 33s.

The configurations of the first middle core section 31f and the second middle core section 31s are the same. The configurations of the first end core portion 33f and the second end core portion 33s are the same. The following description will be made with reference to the first middle core section 31f and the first end core section 33f.

The first middle core portion 31f has a prismatic shape. The first middle core portion 31f of this embodiment has a quadrangular prism shape. The four corners of the square prism are rounded. That is, the outer circumferential surface of the first middle core portion 31f, excluding the first end surface and the second end surface, is composed of four planes and four corners.

One of the four corners is the first corner 311. As shown in FIGS. 2 to 4, the first corner portion 311 has a plurality of first recesses 312 arranged in a direction along the axis of the first middle core portion 31f. The plurality of first recesses 312 are continuous in the direction along the axis. A first bent portion 213 of the winding 21 in each turn of the first winding portion 2i, which will be described later with reference to FIG. 6, is arranged in each first recess 312. The cross-sectional shape of each first recess 312 cut along the axis can be appropriately selected depending on the cross-sectional shape of the winding 21. As will be described later, the winding 21 of this embodiment is a covered rectangular wire. As shown in FIGS. 3 and 4, the cross-sectional shape of each first recess 312 in this embodiment is triangular. More specifically, the cross-sectional shape of each first recess 312 is a right triangle. In addition, in FIG. 4, the cross-sectional shape of each first recess 312 is not shown to be a right triangle, and the cross-section of the winding 21 is not shown to be rectangular. This is because the first recessed portion 312 extends in a twisted manner along the first bent portion 213. This point also applies to FIG. 7, which will be described later.

The two adjacent sides forming right angles of the right triangle are the first adjacent side facing the short side of the winding 21 and the second adjacent side facing the long side of the winding 21. As will be described later, the first winding portion 2i of this embodiment is formed by winding a coated rectangular wire edgewise. The length of the first adjacent side in this embodiment is substantially the same as the short side of the winding 21 . The length of the second adjacent side in this embodiment is shorter than the long side of the winding 21 . FIG. 5 shows a cross-sectional view taken along a plane passing through a right-angled vertex of a right-angled triangle and perpendicular to the direction along the axis. As shown in FIG. 5, in the first recess 312, the depth at the center of the first middle core portion 31f in the direction around the axis is the deepest, and in the first recess 312, the depth at both ends in the direction around the axis is the shallowest. Both ends of the first recess 312 in the direction around the axis and both planes adjacent to the first corner 311 are flush with each other.

In this embodiment, as shown in FIG. 2, one of the two corners adjacent to the first corner 311 in the direction around the axis of the first middle core portion 31f is the second corner 313. The second corner portion 313 has a plurality of second recesses 314 arranged in a direction along the axis. A second bent portion 214 of each turn of the winding 21, which will be described later with reference to FIG. 6, is arranged in each second recess 314. The plurality of second recesses 314 are continuous in the direction along the axis. The configuration of each second recess 314 is the same as that of the first recess 312.

In this embodiment, the remaining two corners are the third triangular parts 315. The third triangular portion 315 is a corner portion that is not provided with the first recessed portion 312 and the second recessed portion 314 and is formed of an arcuate surface.

Unlike this embodiment, one of the four corners may be the first corner 311 and the remaining three corners may be the third triangular section 315.

The shape of the first end core portion 33f is columnar. The shape of the first end core portion 33f of this embodiment is a columnar shape having a substantially dome-shaped upper surface and a lower surface.

The first middle core portion 31f and the first end core portion 33f are composed of a molded body, a powder molded body, or a laminate of a composite material.

A molded body of a composite material is a molded body in which soft magnetic powder is dispersed in a resin. A molded body of a composite material is obtained by filling a mold with a fluid material in which soft magnetic powder is dispersed in an unsolidified resin, and then solidifying the resin. A composite material molded body in which the first recess 312 and further the second recess 314 are formed can be produced by transferring a mold. In the molded body of a composite material, the content of soft magnetic powder in the resin can be easily adjusted. Therefore, it is easy to adjust the magnetic properties of the molded body of the composite material. Furthermore, composite material compacts are easier to form even in complex shapes compared to powder compacts. An example of the content of the soft magnetic powder in the molded body of the composite material is 20 volume % or more and 80 volume % or less. An example of the content of the resin in the molded body of the composite material is 20% by volume or more and 80% by volume or less. These contents are values when the molded body of the composite material is 100% by volume.

A powder compact is a compact formed by compression molding soft magnetic powder. A powder compact is obtained by filling a cavity with soft magnetic powder and pressing the soft magnetic powder in the cavity with a punch. The compacted powder body provided with the first recess 312 and further the second recess 314 can be produced by transfer using at least one of a cavity and a punch. The powder compact can have a higher proportion of the soft magnetic powder in the core portion 30 than the composite material compact. Therefore, the powder compact easily improves magnetic properties. The magnetic properties include relative magnetic permeability and saturation magnetic flux density. In addition, since the powder compact contains a larger amount of soft magnetic powder than the composite material compact, it has excellent heat dissipation properties. An example of the content of magnetic powder in the powder compact is 85% by volume or more and 99% by volume or less. This content is a value when the powder compact is 100% by volume.

The particles constituting the soft magnetic powder are soft magnetic metal particles, coated particles, soft magnetic nonmetal particles, and the like. The coated particle may include a soft magnetic metal particle and an insulating coating provided around the outer periphery of the soft magnetic metal particle. The soft magnetic metal is pure iron or an iron-based alloy. An example of an iron-based alloy is a Fe (iron)-Si (silicon) alloy or a Fe-Ni (nickel) alloy. An example of an insulating coating is phosphate. An example of a soft magnetic nonmetal is ferrite.

An example of the resin of the molded body of the composite material is a thermosetting resin or a thermoplastic resin. Examples of thermosetting resins are epoxy resins, phenolic resins, silicone resins, or urethane resins. Examples of thermoplastic resins are polyphenylene sulfide resins, polyamide resins, liquid crystal polymers, polyimide resins, or fluorine resins. An example of a polyamide resin is nylon 6, nylon 66, or nylon 9T.

The molded body of the composite material may contain a filler. An example of a filler is alumina or silica. Fillers contribute to improving heat dissipation and electrical insulation.

The content of the soft magnetic powder in the molded body of the composite material and the content of the soft magnetic powder in the compacted body are considered to be equivalent to the area ratio of the soft magnetic powder in the cross section of the molded body. The content of soft magnetic powder in the compact is determined as follows. A cross section of the molded body is observed with a SEM (scanning electron microscope) to obtain an observed image. The cross section of the molded body is an arbitrary cross section. The magnification of SEM shall be 200 times or more and 500 times or less. The number of observation images to be acquired is 10 or more. The total area of all observed images shall be 0.1 cm ² or more. One observation image may be acquired for each cross section, or a plurality of observation images may be acquired for each cross section. Each acquired observation image is processed to extract the outline of the particle. The image processing is, for example, binarization processing. The area ratio of soft magnetic particles is calculated in each observed image, and the average value of the area ratio is determined. The average value is regarded as the content of soft magnetic powder.

The laminate is made by laminating multiple magnetic thin plates. The magnetic thin plate has an insulating coating. The magnetic thin plate is, for example, an electromagnetic steel plate. The laminate in which the first recess 312 and further the second recess 314 are provided can be produced by laminating a plurality of magnetic thin plates having different areas in a direction along the thickness of the magnetic thin plates.

The first middle core part 31f, the second middle core part 31s, the first end core part 33f, and the second end core part 33s of this embodiment are made of a molded body of a composite material.

(gap material)
The gap material is made of a material having a relative magnetic permeability lower than that of the first middle core part 31f, the second middle core part 31s, the first end core part 33f, and the second end core part 33s. An example of the constituent material of the gap material is the above-mentioned ceramic or resin.

[coil]
The coil 2 of this embodiment shown in FIG. 2 has a first winding part 2i and a second winding part 2e. The winding section 20 of this embodiment constitutes each of a first winding section 2i and a second winding section 2e. The first winding portion 2i and the second winding portion 2e may or may not be connected to each other. The first winding portion 2i is arranged on the outer periphery of the first middle core portion 31f. The second winding portion 2e is arranged on the outer periphery of the second middle core portion 31s. The configurations of the first winding part 2i and the second winding part 2e are the same. The following description will be made regarding the first winding portion 2i as a representative.

The first winding portion 2i has a square cylindrical shape. The corners of the first winding portion 2i are rounded. The first winding portion 2i is made up of a winding 21. The winding 21 is wound in a plurality of turns along the outer peripheral surface of the first middle core portion 31f. The square cylindrical first winding portion 2i is easy to manufacture because it is easy to wind the winding 21 along the outer peripheral surface of the first middle core portion 31f during the manufacturing process. As the winding 21, a known winding can be used. The winding 21 of this embodiment is a covered rectangular wire. The conductor wire of the covered rectangular wire is made of copper rectangular wire. The insulation coating of the coated rectangular wire is made of enamel. The first winding portion 2i is formed by winding a coated rectangular wire edgewise. When the length of the first winding part 2i in the direction along the axis is constant, the first winding part 2i wound edgewise has a smaller turn than the first winding part 2i winding flatwise. Easy to increase in number. When the number of turns of the first winding part 2i is constant, the first winding part 2i wound edgewise has a longer length along the axis than the first winding part 2i winding flatwise. It is easy to shorten the length. Therefore, the first winding part 2i wound edgewise is easier to downsize than the first winding part 2i winding flatwise. Each turn of the winding 21 of the first winding portion 2i is composed of four straight parts and four bent parts.

As shown in FIG. 6, the four straight parts in this embodiment are one first straight part 211 and three second straight parts 212. The four bent portions in this embodiment are one first bent portion 213 , one second bent portion 214 , and two third bent portions 215 . The first straight portion 211 intersects the direction along the axis of the first winding portion 2i without being perpendicular to it. The second straight portion 212 is perpendicular to the direction along the axis of the first winding portion 2i. The first bent portion 213 connects the first straight portion 211 and the second straight portion 212. The second bent portion 214 connects the first straight portion 211 and the second straight portion 212 of the adjacent turn. The first bent portion 213 and the second bent portion 214 are locations where the winding 21 is bent and shifted in the direction along the axis of the first winding portion 2i. That is, the first bent portion 213 and the second bent portion 214 are twisted. The third bent portion 215 connects the second straight portions 212. The third bending portion 215 is a portion where the winding 21 is bent but not displaced in the direction along the axis of the first winding portion 2i. That is, the third bent portion 215 is not twisted. Unlike this embodiment, the four bent portions may be one first bent portion 213 and three third bent portions 215.

Each first straight portion 211 is in contact with a plane connecting the first corner 311 and the second corner 313. The three second linear parts 212 of each turn are a plane that connects the first corner part 311 and the second triangular part 315, a plane that connects the second corner part 313 and the second triangular part 315, and a plane that connects the second triangular parts 315. is in contact with The heat of the winding 21 in which each of the first linear portions 211 and the second linear portions 212 are in contact with the first middle core portion 31f is easily transmitted to the first middle core portion 31f. Therefore, the reactor 1 of this embodiment can easily improve heat dissipation compared to a conventional reactor in which a gap is formed between the first winding part 2i and the first middle core part 31f.

Each first bent part 213 is arranged in each first recessed part 312. Each first bent portion 213 is in contact with the first corner portion 311 . Each second bent portion 214 is disposed in a respective second recess 314 . Each second bent portion 214 is in contact with the second corner portion 313 . The two third bent portions 215 of each turn are in contact with each third triangular portion 315.

The reactor 1 of this embodiment, in which each first bent part 213 is arranged in each first recess 312 and each second bent part 214 is arranged in each second recess 314, is compared with the reactor of the following reference example. This makes it easy to improve heat dissipation. In the reactor of the reference example, unlike the present embodiment, the winding 21 is wound around a first middle core portion 31f that does not have the first recess 312 and the second recess 314. In the reactor of the reference example, gaps are likely to be formed between each twisted first bent part 213 and the second triangular part 315 and between each twisted second bent part 214 and the second triangular part 315. Therefore, the contact area between the first bent portion 213 and the second bent portion 214 and the first middle core portion 31f in the reactor of the reference example tends to be small. On the other hand, each first bending part 213 and each second bending part 213 and each second bending part 213 and each second bending part 213 and each second bending part 213 and each second bending part 213 and each second bending part 214 are arranged in each second recess 314, respectively. The contact area between the portion 214 and the first middle core portion 31f tends to be large. Therefore, the reactor 1 of this embodiment can easily transfer the heat of the winding 21 to the first middle core portion 31f compared to the reactor of the reference example.

Each third bent portion 215 is in contact with the third triangular portion 315. Unlike the first bent portions 213, each third bent portion 215 is not twisted, so even the third triangular portion 315, which is a curved surface without a recess, can easily come into contact with each other.

The first winding portion 2i is produced by winding the winding wire 21 along the outer peripheral surface of the first middle core portion 31f. In the manufacturing process, the first bent portion 213 is aligned with the first recessed portion 312 and the second bent portion 214 is aligned with the second recessed portion 314.

《Other embodiments》
The reactors of Embodiments 2 to 5, which are different from Embodiment 1, will be described. The description of the second to fifth embodiments will focus on the differences from the first embodiment. Descriptions of configurations similar to those in Embodiment 1 may be omitted.

《Embodiment 2》
As shown in FIG. 7, in the reactor of the second embodiment, the first winding part 2i and the second winding part 2e may be configured by flatwise winding a covered rectangular wire. The first winding part 2i and the second winding part 2e formed by flatwise winding bend the coated rectangular wire, compared to the first winding part 2i and the second winding part 2e formed by edgewise winding. It is simple and easy to manufacture. In this embodiment, the cross-sectional shape of each first recess 312 and each second recess 314 is a right triangle, as in the first embodiment. In this embodiment, the length of the second adjacent side facing the long side of the winding 21 among the two adjacent sides forming a right angle of the right triangle is substantially the same as the long side of the winding 21 . Of the two adjacent sides of the right triangle, the first adjacent side facing the short side of the winding 21 is shorter than the short side of the winding 21 .

《Embodiment 3》
As shown in FIG. 8, in the reactor of the third embodiment, each first recess 312 and each second recess 314 have a semicircular cross-section, and the winding 21 may be a round wire.

《Embodiment 4》
As shown in FIGS. 9 and 10, as the reactor of the fourth embodiment, the core section 30 may include a core body section 30a and an insulating section 30b provided along the outer peripheral surface of the core body section 30a. good. The insulating portion 30b tends to increase the insulation between the core body portion 30a and the winding portion 20. The core body portion 30a is made of the above-mentioned molded body or laminate. The insulating portion 30b is made of, for example, the same resin as the resin of the composite material molded body described above. The core body portion 30a and the insulating portion 30b of this embodiment are integrated. Unlike this embodiment, the core body portion 30a and the insulating portion 30b may be independent from each other.

The core body portion 30a of this embodiment has a quadrangular prism shape. The outer circumferential surface of the core body portion 30a is composed of four planes and four corners.

As shown in FIG. 9, one of the four corners of the core body 30a may have a plurality of recesses 318 arranged in the direction along the axis of the core body 30a. Although not shown, one of the two corners adjacent in the direction around the axis of the core body 30a to the corner provided with the plurality of recesses 318 also has a plurality of recesses 318. It's okay. The remaining two corners are arcuate corners.

As shown in FIG. 9, the insulating portion 30b has a first corner portion 311 in which the plurality of first recesses 312 described above are provided. The first corner portion 311 of the insulating portion 30b is provided so as to cover the corner portion where the plurality of recesses 318 are provided among the four corners of the core body portion 30a. The first recess 312 of the insulating portion 30b is along the recess 318 of the core body portion 30a. Although not shown, the insulating portion 30b may further include a second corner portion provided with the plurality of second recesses described above. The second corner portion of the insulating portion 30b has a plurality of corners among two corners adjacent in the direction around the axis of the core body portion 30a with respect to the corner portion having a plurality of recesses 318 covered by the first corner portion 311. It is provided so as to cover the corner portion where the recessed portion 318 is provided. The second recess of the insulating portion 30b is along the recess 318 covered by the second corner. In addition to the two corners described above, the insulating section 30b may cover the remaining two corners of the core body section 30a. Furthermore, the insulating portion 30b may cover four planes of the core body portion 30a. That is, the insulating portion 30b may be provided so as to cover the entire outer peripheral surface of the core body portion 30a.

Unlike the example shown in FIG. 9, as shown in FIG. 10, none of the four corners of the core main body 30a has a plurality of recesses 318, and is a corner formed by an arcuate surface. It's okay. As shown in FIG. 10, the first corner part 311 in which the plurality of first recesses 312 described above are provided in the insulating part 30b is provided so as to cover the corner part formed by the circular arc surface in the core body part 30a. You can leave it there. Although not shown, the second corner portion of the insulating portion 30b in which the plurality of second recesses described above is provided is located in the core body portion relative to the corner portion covered by the first corner portion 311 in the core body portion 30a. It may be provided so as to cover one corner of two corners adjacent in the direction around the axis of 30a.

《Embodiment 5》
Although not shown, in the reactor of Embodiment 5, the magnetic core may include a middle core part, a first side core part, a second side core part, a first end core part, and a second end core part. The middle core part, the first side core part, and the second side core part are arranged side by side so that the directions along the respective axes are parallel to each other. A middle core section is arranged between the first side core section and the second side core section. The first side core portion is arranged to face the first end surface of the middle core portion, the first end surface of the first side core portion, and the first end surface of the second side core portion. The second side core portion is disposed facing the second end surface of the middle core portion, the second end surface of the first side core portion, and the second end surface of the second side core portion.

The magnetic core is configured by, for example, a combination of an E-shaped first core piece and an I-shaped second core piece, or a combination of a U-shaped first core piece and a T-shaped second core piece. can. The E-shaped first core piece is a molded body or a laminate in which a middle core part, a first side core part, a second side core part, and a first end core part are integrated. The I-shaped second core piece is constituted by a second end core portion. The U-shaped first core piece is a molded body or a laminate in which a first side core part, a second side core part, and a first end core part are integrated. The T-shaped second core piece is a molded body or a laminate in which a middle core portion and a second end core portion are integrated.

In this embodiment, the core portion 30 described in Embodiment 1 may constitute each of the first side core portion and the second side core portion. The first winding part 2i mentioned above may be arranged on the outer periphery of the first side core part, and the second winding part 2e mentioned above may be arranged on the outer periphery of the second side core part. The first winding part 2i and the second winding part 2e may be independent from each other.

《Embodiment 6》
[Converter/power conversion device]
The reactor 1 of any one of Embodiments 1 to 5 can be used for applications that satisfy the following energization conditions. The energization conditions are as follows. The maximum direct current is, for example, about 100 A or more and 1000 A or less. The average voltage is, for example, about 100V or more and 1000V or less. The frequency used is, for example, about 5 kHz or more and 100 kHz or less. The reactor 1 of any one of Embodiments 1 to 5 is typically a component of a converter installed in a vehicle 1200 such as an electric vehicle, a hybrid vehicle, or a fuel cell vehicle, or a power converter equipped with this converter. Can be used as component parts of equipment.

As shown in FIG. 11, the vehicle 1200 includes a main battery 1210, a power converter 1100 connected to the main battery 1210, and a motor 1220 that is driven by power supplied from the main battery 1210 and used for traveling. Motor 1220 is typically a three-phase AC motor. The motor 1220 drives the wheels 1250 during running, and functions as a generator during regeneration. In the case of a hybrid vehicle, vehicle 1200 includes an engine 1300 in addition to a motor 1220. In FIG. 11, an inlet is shown as a charging location of vehicle 1200, but it may be provided with a plug.

Power conversion device 1100 includes a converter 1110 and an inverter 1120. Converter 1110 is connected to main battery 1210. Inverter 1120 is connected to converter 1110. Inverter 1120 performs mutual conversion between direct current and alternating current. Converter 1110 shown in this example boosts the input voltage of main battery 1210, which is approximately 200 V or more and 300 V or less, to approximately 400 V or more and 700 V or less, and supplies power to inverter 1120 when vehicle 1200 is running. During regeneration, the converter 1110 steps down 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. When the vehicle 1200 is running, the inverter 1120 converts the DC boosted by the converter 1110 into a predetermined alternating current and supplies power to the motor 1220. During regeneration, inverter 1120 converts the AC output from motor 1220 into DC and outputs it to converter 1110.

As shown in FIG. 12, 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. Converter 1110 converts the input voltage by repeating ON/OFF. Input voltage conversion here means step-up and step-down. As the switching element 1111, a power device such as a field effect transistor or an insulated gate bipolar transistor is used. The reactor 1115 utilizes the property of a coil to prevent changes in the current flowing through the circuit, and has the function of smoothing out changes when the current attempts to increase or decrease due to switching operations. As the reactor 1115, the reactor 1 of any one of Embodiments 1 to 5 is provided. Power conversion device 1100 and converter 1110 including reactor 1 can be expected to have improved heat dissipation.

In addition to the converter 1110, the vehicle 1200 includes a power supply device converter 1150 and an auxiliary power supply converter 1160. Power supply device converter 1150 is connected to main battery 1210. Auxiliary power supply converter 1160 is connected to sub-battery 1230 and main battery 1210, which serve as power sources for auxiliary equipment 1240. Auxiliary power supply converter 1160 converts the high voltage of main battery 1210 to low voltage. Converter 1110 typically performs DC-DC conversion, while power supply device converter 1150 and auxiliary power supply converter 1160 perform AC-DC conversion. Some power supply device converters 1150 perform DC-DC conversion. The reactors of the power supply device converter 1150 and the auxiliary power supply converter 1160 can be provided with the same configuration as the reactor 1 of any one of Embodiments 1 to 5, and a reactor whose size, shape, etc. are changed as appropriate can be used. Further, the reactor 1 of any one of Embodiments 1 to 5 can be used in a converter that converts input power, such as a converter that only steps up or a converter that only steps down.

The present invention is not limited to these examples, but is indicated by the scope of the claims, and is intended to include all changes within the meaning and scope equivalent to the scope of the claims.

1 Reactor 2 Coil 20 Winding part, 2i First winding part, 2e Second winding part 21 Winding 211 First straight part, 212 Second straight part 213 First bent part, 214 Second bent part, 215 Third Bending part 3 Magnetic core, 30 Core part 30a Core body part, 30b Insulating part 31f First middle core part, 31s Second middle core part 311 First corner part, 312 First recessed part 313 Second corner part, 314 Second recessed part 315 Second Triangular part 318 Recessed part 33f First end core part, 33s Second end core part 1100 Power converter, 1110 Converter 1111 Switching element, 1112 Drive circuit, 1115 Reactor 1120 Inverter 1150 Power supply device converter, 1160 Auxiliary power supply converter 1200 Vehicle 1210 Main Battery, 1220 Motor, 1230 Sub-battery 1240 Auxiliary equipment, 1250 Wheels 1300 Engine

Claims (11)

1. a magnetic core having a core portion configured in a prismatic shape;
   a coil having a winding part arranged around the outer periphery of the core part,
   The core portion includes a first corner portion having a plurality of first recesses arranged in a direction along the axis of the core portion,
   The winding part is composed of a winding wire wound in a plurality of turns along the outer peripheral surface of the core part,
   The winding of each of the plurality of turns is
   one first straight portion that intersects the direction along the axis of the winding portion without being perpendicular to it;
   a second linear portion perpendicular to the direction along the axis of the winding portion;
   a first bent part connecting the first straight part and the second straight part,
   the first bent portion in each of the plurality of turns is disposed in each of the plurality of first recesses;
   reactor.
2. The core portion has a second corner portion adjacent to the first corner portion in a direction around the axis of the core portion,
   The second corner portion has a plurality of second recesses arranged in a direction along the axis of the core portion,
   The winding of each of the plurality of turns has a second bent part connected to the first straight part,
   The reactor according to claim 1, wherein the second bent portion in each of the plurality of turns is arranged in each of the plurality of second recesses.
3. The winding wire is a flat wire,
   The reactor according to claim 2, wherein each of the plurality of first recesses and each of the plurality of second recesses has a triangular cross-sectional shape when cut along the axis of the core portion.
4. The reactor according to claim 3, wherein the winding portion is formed by winding the rectangular wire flatwise.
5. The reactor according to claim 3, wherein the winding portion is formed by winding the flat wire edgewise.
6. The core portion has a quadrangular prism shape,
   The reactor according to any one of claims 1 to 5, wherein the winding portion has a rectangular cylindrical shape.
7. The core portion is
   A core body mainly made of magnetic material,
   an insulating part provided along the outer peripheral surface of the core main body part,
   The reactor according to any one of claims 1 to 6, wherein the plurality of first recesses are provided in the insulating part.
8. It has a prismatic core,
   The core portion includes a first corner portion having a plurality of first recesses arranged in a direction along the axis of the core portion.
   magnetic core.
9. The core portion has a second corner portion adjacent to the first corner portion in a direction around the axis of the core portion,
   The magnetic core according to claim 8, wherein the second corner portion has a plurality of second recesses arranged in a direction along the axis of the core portion.
10. comprising the reactor according to any one of claims 1 to 7,
    converter.
11. comprising the converter according to claim 10;
    Power converter.

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