JP6075678B2 - Composite magnetic core, reactor and power supply - Google Patents

Description

  The present invention relates to a reactor used in a power supply device such as a booster and a composite magnetic core thereof. Such a power supply device is used, for example, to drive a high-output electric motor such as a hybrid vehicle or an electric vehicle.

  2. Description of the Related Art In recent years, hybrid vehicles and electric vehicles that have begun to spread rapidly are equipped with a high-output electric motor, and a reactor that can withstand high voltage and large current is used for a power supply circuit that drives the motor. In the reactor, a magnetic core material having a high saturation magnetic flux density Bs is used, and an effective magnetic permeability is lowered by providing a gap between the magnetic core materials, so that magnetic saturation is difficult even at a large current. For example, for applications such as hybrid vehicles, the effective permeability μre is in the practical range of approximately 10 to 50.

  As a magnetic core material of a reactor for a power supply device, in general, in a region of 20 kHz or less, mainly a silicon steel plate, an amorphous soft magnetic ribbon, and a microcrystalline soft magnetic ribbon, in a region exceeding 20 kHz, Mn—Zn or Ni -Zn-based ferrites are widely used. The former has the advantages that the saturation magnetic flux density Bs and the magnetic permeability μ are high, and the latter ferrite has the advantages that the high-frequency core loss is small, the degree of freedom in shape is high, and the mass productivity is excellent. In addition, in the region from 5 kHz to 100 kHz, a dust core is also used. The dust core is obtained by insulating the surface of the magnetic powder and then molding, and the electrical resistance is increased and the eddy current loss is suppressed by the insulating treatment.

  As described above, a magnetic material having a high saturation magnetic flux density Bs is used for a reactor for high current, and a gap is provided between the magnetic core materials. However, in this case, a fringing magnetic flux is generated in which the magnetic flux leaks outside the gap. Here, when the above-mentioned amorphous soft magnetic ribbon or the like is used as a magnetic core material having a high saturation magnetic flux density Bs, an eddy current due to fringing magnetic flux is generated on the side surface of the magnetic core in the vicinity of the gap, and the core loss increases. . On the other hand, in patent document 1, as shown in FIG. 7, between the high permeability magnetic core parts 71 and 72, such as an amorphous soft magnetic ribbon, the powder magnetic core parts 73-78 with large electrical resistance are arrange | positioned. By providing the gaps 79 to 82 between the dust cores, loss caused by the fringing magnetic flux is reduced.

JP 2007-12647 A

  According to the configuration described in Patent Document 1, it is possible to reduce the loss by disposing the gap between the dust core portions as compared with the case where the gap is disposed between the core portions of the amorphous soft magnetic ribbon. . Here, the dust core is manufactured by pressure molding using a mold. In the case of pressure molding, from the viewpoint of moldability, it is common to provide rounds at the four corners of the cavity having a rectangular bottom surface. On the other hand, the cross section of the magnetic core of the amorphous soft magnetic ribbon is usually a perfect rectangle. Therefore, in order to match the magnetic core section of the amorphous soft magnetic ribbon with the magnetic core cross-sectional shape, when obtaining a complete rectangular solid core as shown in FIG. The manufacturing process of the composite magnetic core has become complicated.

  In view of the above problems, an object of the present invention is to provide a composite magnetic core and a reactor configuration that are suitable for reducing the loss of a large current reactor and that can be manufactured by a simple method.

A composite magnetic core according to the present invention includes a pair of dust cores facing each other in parallel, and a pair of stacked cores that are a laminate of magnetic metal plates, facing each other via the dust core. and a composite magnetic core ring are magnetic gap disposed between the front Symbol dust core portion and the laminated magnetic core portions, the dust core portions each comprising at least one rectangular dust core block, the dust core block has a radius parallel four ridge portions to each other, the ridge line portion with the Earl, the laminated sides of the two sides portions in the stacking direction of the core portion a magnetic metal plate facing to Turkey And features. According to such a configuration, the R formed on the dust core block is disposed on the surface side facing the end surface of the laminated magnetic core portion, and is not disposed in the ridge line direction perpendicular to the end surface. However, the cross-sectional shape in the direction perpendicular to the magnetic path can be matched with the end face shape of the laminated magnetic core portion, and the manufacturing process is simplified.

Prior Symbol composite core, ridge having an end surface of the laminated magnetic core portions, it between the dust core block facing, Oite to configure magnetic gap that is provided, the radius of the dust core block moiety, by two sides portions opposed on either side of the stacking direction of the magnetic metal plate of the laminated core portion, it is possible to reduce a loss due to fringing flux at the interface between the product layer core portion and the dust core portion . Further, it is preferable that a magnetic gap is provided in a dust core portion composed of a plurality of dust core blocks, and the adjacent dust core blocks have opposite ridge lines.

  Furthermore, in the composite magnetic core, it is preferable that the laminated magnetic core portion includes a corner portion and straight portions integral with the corner portion at both ends of the corner portion. Since the linear part is provided in the laminated magnetic core part, the coil can be arranged across the linear part and the dust core part. Therefore, a reactor suitable for magnetic flux leakage suppression can be configured.

Furthermore, in the composite magnetic core, it is preferable that the end surface of the laminated magnetic core portion has a chamfered portion at a portion facing a ridge line portion having a rounded portion of the dust core block . Such a configuration is even more effective for reducing losses due to fringing magnetic flux.

  The reactor of this invention is equipped with one of the said composite magnetic cores, and the coil which circulates at least the said powder magnetic core part, It is characterized by the above-mentioned.

  The power supply device of the present invention is characterized by using the reactor.

  ADVANTAGE OF THE INVENTION According to this invention, while being suitable for the loss reduction of the reactor for large currents, the structure of the composite core and reactor which can be manufactured with a simple method can be provided.

It is a figure which shows embodiment of the composite magnetic core which concerns on this invention. It is a figure which shows other embodiment of the composite magnetic core which concerns on this invention. It is a figure which shows other embodiment of the composite magnetic core which concerns on this invention. It is a figure which shows other embodiment of the composite magnetic core which concerns on this invention. It is a figure which shows embodiment of the reactor which concerns on this invention. It is a circuit diagram of the boost type DC-DC converter which is a power supply device using the reactor which concerns on this invention. It is a figure which shows the conventional reactor.

  Hereinafter, embodiments of the composite magnetic core and the like according to the present invention will be specifically described with reference to the drawings. However, the present invention is not limited thereto. Moreover, the structure demonstrated in each embodiment is applicable also in other embodiment, unless the meaning of other embodiment is impaired, In that case, the overlapping description is abbreviate | omitted suitably.

(First and second embodiments of composite magnetic core)
1A is a perspective view showing an embodiment of a composite magnetic core of the present invention, FIG. 1B is a plan view thereof, and FIG. 1C is a front view thereof. A composite magnetic core 11 shown in FIG. 1 includes a pair of dust cores 1 and 2 arranged in parallel and a pair of laminated cores 3 and 4 arranged via the dust cores 1 and 2. An annular composite magnetic core with The composite magnetic core 11 has a substantially rectangular shape. The term “substantially rectangular” means that it is recognized as a rectangle as a whole except for rounded corners, and the rectangle includes a square. The dust cores 1 and 2 are rectangular parallelepipeds, and are I-shaped magnetic cores formed by mixing and molding magnetic powder, an insulating material, a binder, and the like. The laminated magnetic core portions 3 and 4 are laminated bodies of magnetic metal plates, and the lamination direction is the radial direction of the annular composite magnetic core. The laminated magnetic core portions 3 and 4 are U-shaped magnetic cores each including a corner portion 3a and 4a and linear portions 3b and 4b integrated with the corner portions 3a and 4a at both ends of the corner portions 3a and 4a. Such a U-shaped magnetic core is, for example, a so-called cut core obtained by winding a soft magnetic alloy ribbon in a substantially rectangular shape and dividing the obtained wound body at the straight portion. Hereinafter, unless otherwise specified, the laminated magnetic core is described as such a cut core.

  The dust core portions 1 and 2 may be provided with at least one cuboid dust core block, respectively. However, in the embodiment shown in FIG. 1, each dust core portion is composed of one dust core block 1a and 2a. It is configured. The dust core blocks 1a and 2a have R Cb at four ridge line portions parallel to each other. The ridge portion is a portion of a side where two adjacent surfaces intersect perpendicularly. Such R Cb can be provided by processing or the like, but is typically obtained by pressure molding using a mold. In the case of pressure molding using a mold, rounds are provided at the four corners of a cavity having a rectangular cross section from the viewpoints of moldability and punchability. Since the dust core blocks 1a and 2a having R Cb in four ridge portions parallel to each other are arranged so that the ridge portion having R Cb faces the end faces of the laminated core portions 3 and 4, the magnetic path The cross-sectional shape of the dust core block in the vertical direction (zx plane direction) is a rectangle in which R Cb does not appear. Note that the term “opposite” here includes the case where another member is interposed therebetween. On the other hand, since the laminated magnetic core portions 3 and 4 are formed by dividing a wound body of a soft magnetic alloy ribbon, the end surfaces thereof are usually rectangular with no radius. Here, if the dust core block is arranged so that the direction in which the radius Cb extends is the direction perpendicular to the end face of the laminated magnetic core portion (y direction), that is, the direction parallel to the magnetic path, only the round portion The cross-sectional area of the dust core block is lost, and magnetic saturation is likely to occur. On the other hand, by arranging the ridge line portion having the radius Cb so as to face the end surfaces of the laminated magnetic core portions 3 and 4, these are not required for processing to remove the radius of the dust core block. It is possible to make the cross-sectional shape of the dust core block and the end surface shape of the laminated core portion the same. Therefore, this configuration contributes to suppression of magnetic saturation and simplifies the manufacturing process.

Magnetic gap between the pressure powder core portion 2 of the composite magnetic core 11 and the laminated core 3, 4 are arranged. In addition , since the magnetic powder surface is insulated in the dust core, the electric resistance is larger than that of the laminated core, and a magnetic gap may be provided in the dust core. Even if the fringing magnetic flux around the magnetic gap passes, eddy current loss can be suppressed. Therefore, even when the magnetic gap is formed for a large current, the loss of the reactor can be suppressed by disposing the dust core portion on at least one of the magnetic bodies on both sides of the magnetic gap.

As in the embodiment shown in FIG. 1, the end face of the laminated core portions 3 and 4, it opposed dust core blocks 1a, between 2a, it is good preferable to provide the magnetic gap Gcd. This is due to the following reason. The magnetic permeability of the powder magnetic core is lower than that of the laminated magnetic core formed using the soft magnetic alloy ribbon as described above. Therefore, as shown in FIG. 7, even when these are brought into contact without a magnetic gap, if the difference between the magnetic permeability of the laminated magnetic core and the magnetic permeability of the dust core is large, the magnetic flux leaks from the magnetic core. End up. If a magnetic gap is not formed, the leaked magnetic flux inevitably passes through the soft magnetic metal ribbon with a component perpendicular to the plane of the soft magnetic metal ribbon constituting the laminated magnetic core, and the vortex A current is generated and a loss occurs. On the other hand, as in the embodiment shown in FIG. 1, by providing a magnetic gap Gcd between the dust cores 1 and 2 and the linear portions 3b and 4b facing each other, a soft magnetic metal having a fringing magnetic flux is provided. The ratio of the component perpendicular to the plane of the ribbon can be reduced.

  The magnetic gap Gcd may be different on both sides of the dust cores 1 and 2, but in the embodiment shown in the figure, the fringing magnetic flux at one magnetic gap is prevented from becoming too large. The magnetic gap Gcd is the same on both sides of the dust cores 1 and 2. The magnetic gap Gcd may be an air gap, or a nonmagnetic material such as a resin plate, an adhesive, or ceramics may be disposed. From the viewpoint of gap dimensional accuracy and strength, it is more preferable to use ceramics.

Further, in the embodiment shown in FIGS. 1A to 1C , as shown in FIG. 1D, the direction in which the ridge line portion having the radius extends is parallel to the stacking direction of the opposing stacked magnetic core portions ( The direction in which the ridge line portion having the radius extends rather than the x direction is a direction (z direction) perpendicular to the lamination direction of the opposed laminated magnetic core portions .

  From the viewpoint of alleviating the swelling of the fringing magnetic flux, the rounded Cb may be a rounded curved surface or a chamfered surface. However, from the viewpoint of moldability in molding with a metal mold, R Cb is more preferably a curved surface. In addition, the size of the radius is preferably large from the viewpoint of moldability, but if it becomes too large, the portion where the magnetic gap is formed becomes large, so these points may be determined. For example, with respect to the length of one side in a state where the round is not formed, the total length of the portions missing due to the rounds at both ends may be set to 1 to 50%.

  Like the dust core block, it is preferable to have a chamfered portion on the end face of the laminated core portion. As described above, the loss due to the fringing magnetic flux having a component in the lamination direction, that is, the direction perpendicular to the main surface of the soft magnetic alloy ribbon is increased in the laminated magnetic core. Therefore, by providing chamfered portions on the two sides on both sides of the lamination direction among the four sides of the end face of the laminated magnetic core, the swelling of the fringing magnetic flux is alleviated, and the direction perpendicular to the main surface of the soft magnetic alloy ribbon is reduced. The fringing magnetic flux component is suppressed. Note that the laminated magnetic core side is not limited to the two sides, and chamfered portions may be provided on all four sides. Further, the shape of the chamfer of the laminated magnetic core portion is not particularly limited, but a flat chamfer is more preferable with a simple configuration.

  As described above, in the embodiment shown in FIG. 1, the laminated magnetic core portions 3, 4 include corner portions 3 a, 4 a, and linear portions 3 b, 4 b integrated with the corner portions 3 a, 4 a at both ends of the corner portions 3 a, 4 a. Is provided. The pair of linear portions 3b protrude from the corner portion 3a in parallel to each other, have the same length, and their end faces are located on the same plane. A magnetic gap Gcd is provided between the dust core portions 1 and 2 and the straight portions 3b and 4b facing each other. As in the composite magnetic core 21 shown in FIG. 2, it is also possible to form the laminated magnetic core parts 5 and 6 with only the corner part without providing a straight part (second embodiment). However, according to the embodiment shown in FIG. 1 having the straight portion, the magnetic leg portion constituted by the dust core portions 1 and 2 and the straight portions 3b and 4b on both ends of the dust core portion is circulated. When the reactor is configured by arranging the coils, the coils can be arranged across the straight portions 3b and 4b and the dust core portions 1 and 2, so that the magnetic gap Gcd can be covered with the coils. By covering the magnetic gap Gcd with the coil, it is possible to prevent the magnetic flux leaking at the magnetic gap portion from leaking outside the coil.

(Third embodiment of composite magnetic core)
3A is a perspective view showing another embodiment of the composite magnetic core of the present invention, FIG. 3B is a plan view thereof, and FIG. 3C is a front view thereof. In the composite magnetic core 31 shown in FIG. 3, the stacking direction of a pair of stacked magnetic core portions 7 and 8 that are stacked bodies of magnetic metal plates and the arrangement direction of the dust core blocks 1a and 2a having a rounded shape are shown in FIG. And different. That is, the lamination direction of the magnetic metal plates of the laminated magnetic core portions 7 and 8 is the axial direction (z direction) of the annular composite magnetic core. Such a laminated magnetic core part can be obtained, for example, by punching and laminating silicon steel sheets in a U shape and integrating them by means such as welding and adhesion. Similar to the embodiment shown in FIG. 1, the ridge line portions having the rounded Cb of the dust core blocks 1 a and 2 a are arranged so as to face the end faces of the laminated magnetic core portions 3 and 4. In the embodiment shown in FIG. 3, the dust core block 1 a, 2 a is rotated 90 degrees from the embodiment shown in FIG. 1A, and the ridge portion having the radius Cb is in the axial direction of the annular composite magnetic core 31. It is arranged on the upper and lower surfaces. The direction in which the ridge line portion having the radius Cb extends is perpendicular to the laminating direction (z direction) of the opposed laminated magnetic core portions 3 and 4, but may be a direction parallel to the direction (z direction). This is the same as the embodiment shown in FIG.

  The embodiment shown in FIG. 1 to FIG. 3 is an annular composite magnetic core including a pair of dust cores arranged in parallel and a set of laminated cores arranged via the dust core. Although it is an example of this, you may comprise by increasing the number of the powder magnetic core parts opposed in parallel, and the number of lamination | stacking magnetic core parts. For example, two composite magnetic cores shown in FIG. 1 may be juxtaposed, and another annular composite magnetic core may be arranged around these to form a three-phase composite magnetic core.

(Fourth embodiment of composite magnetic core)
In the embodiment shown in FIGS. 1 to 3, the number of dust core blocks in each dust core is one, but the number of dust core blocks may be two or more. FIG. 4 shows another embodiment (fourth embodiment) in which the configuration of the dust core is different from the embodiment shown in FIG. Since parts other than the powder magnetic core are the same as those in the embodiment shown in FIG. In the composite magnetic core 41 shown in FIG. 4, the dust core portions 1 and 2 each have a plurality of dust core blocks 1 a / 1 b / 1 c and 2 a / 2 b / 2 c arranged via a magnetic gap Gdd. In order to secure the required total gap amount, by providing a gap in the dust cores 1 and 2, the magnetic gap between the dust cores 1 and 2 and the straight portions of the laminated cores 3 and 4 is reduced. Therefore, the loss due to the fringing magnetic flux in such a portion can be reduced. Further, in the dust core portion, since the magnetic powder surface is insulated, the electric resistance is large and the eddy current loss is small. Therefore, since an increase in magnetic core loss can be suppressed by providing a magnetic gap in the dust core, such a configuration provides a large current for use in a power supply circuit of 20 A or more in which a gap is provided to reduce the effective permeability μe. Suitable for reactors. In the embodiment shown in FIG. 4, the dust core blocks 1a to 1c (2a to 2c) have the same shape and size, but the lengths in the magnetic path direction may be different. In the embodiment shown in FIG. 4, the direction in which the ridge line portion having the radius extends is the same in all the dust core blocks, and is the direction perpendicular to the stacking direction of the facing stacked magnetic core portions 3 and 4. However, with respect to the dust core blocks arranged between them excluding the dust core blocks at both ends adjacent to the laminate magnetic core portion, the direction in which the ridge line portion having the radius extends is the lamination of the laminate magnetic core portions 3 and 4. The direction may be the same as the direction. Further, in the embodiment shown in FIG. 4, each dust core portion is constituted by three dust core blocks, but the number is not limited to this. When the necessary total gap amount is secured, the number of magnetic gaps in the dust core can be increased to reduce the leakage magnetic flux in each magnetic gap and reduce the loss. In addition, although it is possible to make the sizes of the plurality of magnetic gaps Gdd formed in each dust core portion different from each other, in the embodiment shown in FIG. 4, the leakage magnetic flux per place is reduced. The plurality of magnetic gaps Gdd have the same size. From the viewpoint of the effectiveness of forming the magnetic gap, the ratio of the total magnetic gap amount to the entire average magnetic path length is preferably 1 to 8%. The size of each magnetic gap is preferably 2.5 mm or less.

(First embodiment of the reactor)
FIG. 5 is a cross-sectional view at an intermediate position in the thickness direction of the composite magnetic core, showing an embodiment of the reactor of the present invention including the above-described composite magnetic core and a coil that circulates at least around the dust core. A reactor 51 shown in FIG. 5 circulates a linear magnetic leg portion composed of a composite magnetic core 41, dust core portions 1 and 2, and straight portions 3 b and 4 b on both ends of the dust core portions 1 and 2. Coils 9 and 10 are provided. In the reactor 51 shown in FIG. 5, the composite magnetic core of the embodiment shown in FIG. 4 is used, but the other embodiment may be used. The coils 9 and 10 have a length in the winding axis direction longer than the sum of the dust core portions 1 and 2 and the magnetic gap Gcd at both ends thereof. It arrange | positions so that the magnetic gap Gcd between the linear parts 3b and 4b of the lamination | stacking magnetic core part of the both ends side of this powder magnetic core part 1 and 2 may become inside the coils 9 and 10. FIG. Since the laminated magnetic core portions 3 and 4 are provided with the straight portions 3b and 4b, the magnetic gap Gcd can be covered with the coils using such coils. Note that the lengths of the coils 9 and 10 indicate the length at the winding portion even when a bobbin is used. The magnetic gap Gcd between the dust core portions 1 and 2 and the straight portions 3b and 4b on both ends of the laminated magnetic core portion of the dust core portions 1 and 2 is disposed so as to be inside the coils 9 and 10. As a result, leakage of magnetic flux to the outside of the coil can be reduced.

  The lengths of the coils 9 and 10 in the winding axis direction are set to the length of the dust cores 3 and 4, the length of the two magnetic gaps Gcd on both sides of the dust cores 3 and 4, and the dust core 3, 4 is set to be larger than the total length of one straight portion 3b (or 4b) of the straight portions of the laminated magnetic core portions on both sides of the magnetic core Gd, the magnetic gap Gcd is reduced even if the coil is misaligned. Can be prevented from being located outside. In addition, the magnetic flux Gcd is located at the inner side of the coil between the dust core and the linear portion of the laminated core on both ends of the dust core. In order to ensure such an effect, the position of the magnetic gap Gcd is more preferably 3 mm or more inside from the end of the coil. As shown in FIG. 5, the position of the magnetic gap Gcd is represented by a distance d from the ends of the coils 9 and 10 to the ends of the magnetic gap, that is, the ends of the straight portions 3 b and 4 b of the laminated magnetic core portions 3 and 4. In each magnetic leg, it is more preferable to arrange the coil by using a spacer or the like so that the distance d between the magnetic gap Gcd on both sides and the end of the coil becomes equal.

  The conductor used for the coil may be in various forms such as a rectangular wire having a rectangular cross-sectional shape or a circular round wire. The round wire is excellent in flexibility and easy to wind. On the other hand, in the edgewise coil using a rectangular wire, an unnecessary space is not generated between the wires as compared with the round wire, so that a coil having a high space factor is obtained, which contributes to the miniaturization of the reactor. Moreover, in the same cross-sectional area, when using a round wire, the effect similar to having enlarged the wire diameter is acquired, and the emitted-heat amount can be restrained low. For example, a rectangular wire having a thickness of 1 to 2 mm and a width of about 4 to 8 mm may be used.

  As the soft magnetic alloy ribbon used for the laminated magnetic core portion, for example, an amorphous soft magnetic alloy ribbon such as Fe-Si-B or Fe-Si-BC can be used. Examples of commercially available materials include iron-based amorphous soft magnetic material 2605SA1 manufactured by Metglas, USA. In addition, as a soft magnetic alloy ribbon, for example, a nanocrystalline soft magnetic alloy having a composition of Fe-Si-B-Cu, Fe-Si-B-Cu-Nb, etc., and crystallites of 1000 mm or less crystallized. A ribbon can be used. For example, Finemet (registered trademark) made by Hitachi Metals can be used. A conventional cut core manufacturing method may be applied to the production of the laminated magnetic core. An example is shown below. First, a soft magnetic alloy ribbon is wound around a rectangular core or the like to a predetermined shape, and then heat treatment is performed. The magnetic core after the heat treatment is subjected to resin impregnation using a thermosetting resin, and after the resin is cured, it is cut to obtain a U-shaped cut core. The cut surface of the magnetic core after cutting is subjected to mechanical polishing, chemical polishing, or the like.

  On the other hand, as the magnetic powder for the dust core, for example, pure iron powder, Fe-Si alloy powder containing 6 to 7% Si represented by Fe-6.5% Si, Fe-Al alloy powder, Fe -Si-Al alloy powder, Fe-Ni alloy powder, Fe-Co alloy powder, amorphous soft magnetic alloy powder, microcrystalline soft magnetic alloy powder, and the like. These may be used alone or in combination as appropriate. In particular, Fe—Si alloy powder containing 6 to 7% of Si is excellent in magnetostriction, magnetic core loss, and saturation magnetic flux density Bs, and is a magnetic powder suitable for a dust core portion. The dust core can be manufactured by a normal manufacturing process. For example, an epoxy resin, a polyamide resin, a polyimide resin, a polyester resin, or the like may be used as a resin that imparts insulating properties and also functions as a binder for binding powder. The molding method of the powder magnetic core part is a casting method in which a mixture of magnetic powder and resin is once liquefied and then cast and cured, an injection molding method in which molding is performed by injection molding in a mold, There is a press molding method in which a mixture of a magnetic powder and a binder made of an organic substance or an inorganic substance is filled and pressed to mold a dust core.

  A typical manufacturing method of a composite magnetic core includes an annular composite magnetic core having a pair of dust cores arranged in parallel and a set of laminated magnetic cores arranged via the dust core. The at least one dust core block obtained by uniaxial press molding and having a radius at four ridge lines parallel to each other is used as each dust core portion. The magnetic metal plate is used as a laminate, and these are arranged so as to form a magnetic gap in at least one of the dust core portion and the dust core portion in the dust core portion, and have the R In the manufacturing method, the dust core block is arranged so that a ridge line portion faces an end face of the laminated magnetic core portion. Moreover, the typical manufacturing method of a reactor further includes the process of arrange | positioning the coil which circulates at least the said powder magnetic core part in addition to the manufacturing method of the said composite magnetic core. The coil may be arranged after the annular composite magnetic core is formed, or when forming an annular composite magnetic core using a coil that retains its shape or a coil wound around a bobbin, a dust core portion is attached to the coil. The reactor may be configured by inserting at least one of the laminated magnetic core portions. Furthermore, when the composite magnetic core and the reactor are configured by the above manufacturing method, the dust core portion and the laminated core portion may be arranged so as to be the above-described embodiments.

  Usually, since the facing end face shape (cross-sectional shape) of the dust core portion and the laminated core portion is set to be the same, it is preferable that the difference between the saturation magnetic flux density of the dust core portion and the saturation magnetic flux density of the laminate core portion is small. . For example, it is preferable to set the deviation of the saturation magnetic flux density of the dust core and the saturation magnetic flux density within 20% of the average value of the saturation magnetic flux density of the dust core and the saturation magnetic flux density of the laminated magnetic core, Within 10% is more preferable.

  Next, an example of a DC-DC converter is shown as a power supply device configured using the reactor of the present invention. FIG. 6 shows a circuit configuration of a boost type DC-DC converter having a driving frequency of 10 kHz. The above-described reactor is mounted on the inductor L1 in the figure. In addition, the power supply device to which the reactor of the present invention is applied is not limited to the DC-DC converter as shown in FIG. 6, but can be applied to various high-current power supply devices such as inverters, vehicles, and solar power generation. it can.

1, 2: Powder magnetic core part 3-8: Laminated magnetic core part 9, 10: Coil 71, 72: High permeability magnetic core part 73-78: Powder magnetic core part 79-82: Gap

Claims (6)

An annular composite magnetic core comprising a pair of powder magnetic cores arranged in parallel and a pair of laminated magnetic cores, which are a laminate of magnetic metal plates, opposed to each other through the powder magnetic core. And
A magnetic gap is disposed between the dust core and the laminated core,
Each of the dust core portions includes at least one cuboid dust core block,
The dust core block has rounds at four ridge lines parallel to each other,
The composite magnetic core characterized in that the ridge line portion having the round is opposed to two side portions on both sides in the lamination direction of the magnetic metal plate of the laminated magnetic core portion.   2. The composite magnetic core according to claim 1, wherein a magnetic core is provided in a powder magnetic core portion formed of a plurality of powder magnetic core blocks, and adjacent powder magnetic core blocks face opposite ridge lines.   3. The composite magnetic core according to claim 1, wherein the laminated magnetic core portion includes a corner portion and linear portions integral with the corner portion at both ends of the corner portion. 4. The composite magnetic core according to claim 1 , wherein an end surface of the laminated magnetic core portion has a chamfered portion at a portion facing a ridge line portion having a radius of the dust core block. 5.   A reactor comprising the composite magnetic core according to any one of claims 1 to 4 and a coil that circulates at least the dust core portion.   A power supply apparatus using the reactor according to claim 5.

Images