JP5198363B2 - Reactor - Google Patents

Description

  The present invention relates to a reactor suitable for use in a switching power supply that performs power conversion such as a DC / DC converter.

  Conventionally, a reactor that repeatedly stores and discharges energy is used in a switching power supply such as a DC / DC converter.

  For example, as shown in FIG. 12, the reactor 1 shown in Patent Document 1 has both outer legs whose lengths are shortened to form a magnetic gap 4 with respect to the middle leg part extending upward from the trunk part. A core having a closed magnetic circuit in which an E-type core 2 and an I-type core 3 having a portion are opposed to each other via a pair of magnetic gaps 4 (an insulator is disposed in the magnetic gap 4). The structure 5, the coil 6 wound around the middle leg portion of the E-type core 2, and the plate-like permanent on the outer surface side of the core structure 5 and on both outer surface sides of the pair of magnetic gaps 4, respectively. And a bias magnetic flux generator 9 having a magnet 7 and a core 8 (back yoke).

  The permanent magnet 7 is magnetized so as to have two poles on one side in each of the plate length direction (vertical direction in FIG. 12) and the plate thickness direction, and the opposite poles have the same polarity. And the neutral line where the S poles are interchanged is provided so as to coincide with the center line of the magnetic gap 4.

  In the reactor 1 configured as described above, the bias magnetic flux φm indicated by the broken line formed by the permanent magnet 7 and the main magnetic flux φc indicated by the solid line formed by the coil 6 are opposite to each other in the E-type core 2 and the I-type core 3. The bias magnetic flux φm formed by the permanent magnet 7 flows in the core 8 bypassing the magnetic gap 4.

  In this reactor 1, the main magnetic flux φc formed by the coil 6 does not pass through the permanent magnet 7, so the permanent magnet 7 is not demagnetized, and the magnetic flux formed by the bias magnetic flux φm formed by the permanent magnet 7 and the magnetic flux formed by the coil 6. Since φc is reversed and cancels each other, the magnetic flux is reduced inside the core structure 5, and as a result, the core structure 5 (cross-sectional area) can be made smaller than when the bias magnetic flux generator 9 is not present. Has been.

JP-A-8-316049 ([0009], [0010], FIG. 1)

  By the way, depending on the reactor mounting space of the apparatus in which the reactor 1 according to the conventional technology is to be mounted, it is necessary to save space (volume saving) of the reactor 1 by using a thin permanent magnet 7.

  In this case, in the reactor 1 according to the related art, a part of the main magnetic flux φc formed by the coil 6 is passed through the permanent magnet 7, the core 8, and the permanent magnet 7 from the outer surface side of the I-type core 3. Therefore, there is a problem that a part of the main magnetic flux φc passes through the permanent magnet 7 and demagnetizes the permanent magnet 7.

  In order to prevent the permanent magnet 7 from being demagnetized, it is conceivable to increase the magnetic resistance of the permanent magnet 7. However, in order to increase the magnetic resistance, the permanent magnet 7 is increased in thickness to increase the magnet length. Must be lengthened.

  However, in the reactor 1 having the structure according to the above-described prior art, when the magnet length of the permanent magnet 7 is increased, the problem that the reactor becomes larger (the volume becomes larger) becomes obvious.

  The present invention has been made in consideration of such a problem. The magnet length of a permanent magnet (in this specification, a permanent magnet is also simply referred to as a magnet) while having a small volume (small size). It aims at providing the reactor which can be lengthened.

  In this section, for ease of understanding, reference numerals in the attached drawings are used for explanation. Therefore, the contents described in this section should not be construed as being limited to those having the reference numerals.

  The reactor according to the present invention includes the following features (1) to (5).

  (1) For example, as shown in FIG. 3 (FIG. 9), the body 112 (112A) and at least two legs 114a, 116, 114b (114A, 114B) extending upward from the body 112 (112A) A first core 101 (101A) having a coil 16 (16A, 16B) wound from the lower end side to the upper end side of the leg portion 116 (114A, 114B), and the leg portions 114a, 116, 114b (114A, 114B) and on the upper surface side of the coil 16 (16A, 16B), and the second cores 102a, 102b magnetically connecting the legs 114a, 116, 114b (114A, 114B). (102A), a reactor main body 12 (12A), and a virtual circumscribed cuboid 14 (14A) surrounding the reactor main body 12 (12A). The magnets 201a, 201b, 301a, 301b are disposed adjacent to the upper ends of the legs 114a, 116, 114b (114A, 114B) and on the upper surface of the coils 16 (16A, 16B). Bias magnetic flux generators 21 and 22 (21A) for generating a bias magnetic flux φm opposite to the main magnetic flux φc generated by the coil 16 (16A and 16B) using (201A and 301A). Features.

  According to the invention having this feature (1), the first core, the coil wound from the lower end side to the upper end side of the leg portion of the first core, and the upper surface side of the coil between the leg portions And a second core that magnetically connects the legs, and in a space inside a virtual circumscribed cuboid that surrounds the reactor main body, adjacent to the upper end side of the legs and of the coil Since it is configured to include a bias magnetic flux generation unit that is disposed on the upper surface side and generates a bias magnetic flux that is opposite to the main magnetic flux generated by the coil using a magnet, the reactor has a small volume (small size) Also, the magnet length of the magnet can be increased.

  (2) In the reactor having the above feature (1), for example, as shown in FIG. 3, the reactor main body includes a trunk portion, both outer leg portions and middle leg portions extending upward from the trunk portion. An E-shaped first core 101, a coil wound from the lower end side to the upper end side of the middle leg portion, and an inner surface of one of the outer leg portions and a facing surface of the middle leg portion. And one second core that is arranged on the upper surface side of the coil and magnetically connects one of the outer leg portions and the middle leg portion, and the inner side surface of the other outer leg portion and the middle leg portion. A bias magnetic flux generator, comprising: the other second core disposed between the opposing surfaces and on the upper surface side of the coil, and magnetically connecting the other outer leg and the middle leg. Is composed of first and second bias magnetic flux generators, and the first and second bias magnetic flux generators are the reactors. In the space inside the virtual circumscribed cuboid surrounding the main body, the magnets are arranged adjacent to the front side and the back side of the upper end side of the outer leg part and the middle leg part, respectively, and on the upper face side of the coil. Is used to generate a bias magnetic flux in a direction opposite to the main magnetic flux generated by the coil.

  According to the invention including this feature (2), the E-type first core, the coil wound from the lower end side to the upper end side of the middle leg portion of the first core, and the one outer leg portion One second core that is disposed between the inner side surface and the opposed surface of the middle leg portion and on the upper surface side of the coil and that magnetically connects one of the outer leg portion and the middle leg portion, and the other Between the inner side surface of the outer leg portion and the opposing surface of the middle leg portion and on the upper surface side of the coil, and the other of the other outer leg portion and the middle leg portion that magnetically connect In a space inside a virtual circumscribed cuboid surrounding a reactor main body having a second core, adjacent to the front side and the back side of the upper end side of the outer leg part and the middle leg part, respectively, and of the coil A first and a second magnetic flux that are disposed on the upper surface side and generate a bias magnetic flux opposite to a main magnetic flux generated by the coil using a magnet; Since it is configured to include a second bias magnetic flux generating portion, while a small volume (small) as a reactor, it is possible to increase the magnet length of the magnet.

  (3) In the invention having the above feature (2), the first and second bias magnetic flux generators may include both outer third cores that are magnetically connected to the outer legs, A first magnet and a second magnet arranged inside the outer third core and generating a bias magnetic flux opposite to a main magnetic flux generated by the coil; and a central magnet arranged between the first and second magnets. The third core and the third core can be arranged on the same axis.

  (4) In the reactor having the above feature (1), for example, as shown in FIG. 9, the reactor main body portion is a U-shaped unit having a trunk portion and both outer leg portions extending upward from the trunk portion. The first core 101A, a coil wound from the lower end side to the upper end side of the both outer leg portions, and between the inner side surfaces of the outer leg portions and on the upper surface side of the coil, the both leg portions A magnetically connected second core, wherein the bias magnetic flux generator is adjacent to the periphery of the upper ends of the outer legs in a space in a virtual circumscribed cuboid surrounding the reactor body. And it is arrange | positioned at the upper surface side of the said coil, The bias magnetic flux opposite to the main magnetic flux which the said coil generate | occur | produces using a magnet is characterized by the above-mentioned.

  According to the invention having this feature (4), the U-shaped first core, the coil wound from the lower end side to the upper end side of both outer leg portions of the first core, A space between the inner side surfaces and on the upper surface side of the coil, and a second core that magnetically connects the both leg portions, and in a space in a virtual circumscribed rectangular parallelepiped surrounding the reactor main body portion, A bias magnetic flux generator is disposed adjacent to the periphery of each upper end side and on the upper surface side of the coil, and generates a bias magnetic flux opposite to the main magnetic flux generated by the coil using a magnet. Thus, the magnet length of the magnet can be increased while the reactor has a small volume (small size).

  (5) In the invention having the above-described feature (4), the bias magnetic flux generator is magnetically connected to both outer side surfaces of the outer legs and is disposed along the upper surface of the coil. First and second cores that are disposed between opposite ends of the three cores and along the upper surface of the coil and that generate bias magnetic fluxes that are opposite to the main magnetic flux generated by the coils. And two magnets.

  According to the reactor according to the present invention, the magnet length of the magnet can be increased while the reactor has a small volume (small size).

1 is an exploded perspective view of an outer iron type reactor according to a first embodiment of the present invention. It is a perspective view of the reactor main-body part which comprises an outer iron type reactor. It is a perspective view of an outer iron type reactor. 4A is a plan view of the reactor, FIG. 4B is a cross-sectional view of the reactor in FIG. 4A taken along line IVB-IVB, and FIG. 4C is a cross-sectional view of the reactor in FIG. 4A taken along line IVC-IVC. It is explanatory drawing of the magnetic path of the main magnetic flux which generate | occur | produces with a coil. FIG. 6A is an explanatory diagram depicting the main magnetic flux and the bias magnetic flux in the plan view of the reactor, FIG. 6B is an explanatory diagram depicting the main magnetic flux and the bias magnetic flux in the cross-sectional view of the reactor, and FIG. 6C is the main magnetic flux in the other cross-sectional view of the reactor. It is explanatory drawing which drawn bias magnetic flux. It is a disassembled perspective view of the inner iron type reactor which concerns on 2nd Example of this invention. It is a perspective view of the reactor main-body part which comprises an inner iron type reactor. It is a perspective view of an inner iron type reactor. 10A is a plan view of the reactor, FIG. 10B is a cross-sectional view of the reactor in FIG. 10A taken along line XB-XB, and FIG. 10C is a cross-sectional view of the reactor in FIG. 10A taken along line XC-XC. FIG. 11A is an explanatory diagram depicting the main magnetic flux and the bias magnetic flux in the plan view of the reactor, FIG. 11B is an explanatory diagram depicting the main magnetic flux and the bias magnetic flux in the cross-sectional view of the reactor, and FIG. 11C is the main magnetic flux in the other cross-sectional view of the reactor. It is explanatory drawing which drawn bias magnetic flux. It is explanatory drawing of the magnetic path of the main magnetic flux and bias magnetic flux of the reactor which concerns on a prior art.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an exploded perspective view of the reactor 10 according to the first embodiment of the outer iron type, FIG. 2 is a perspective view of the reactor main body 12 that constitutes the reactor 10, and FIG. 3 is a perspective view of the reactor 10.

  The reactor 10 according to the first embodiment basically includes a reactor main body 12 shown in FIG. 2 and a virtual circumscribed rectangular parallelepiped 14 indicated by a two-dot chain line circumscribing the reactor main body 12 (see FIGS. 2 and 3). ) Of the first and second bias magnetic flux generators 21 and 22 (see FIGS. 1 and 3) disposed in the space.

  The reactor body 12 includes an E-type first core 101, a rectangular tube-like coil 16 that generates a main magnetic flux φc, which will be described later, one I-type second core 102a, and the other I-type second core. 102b. In addition, each core is comprised by laminating | stacking a steel plate, for example.

  The E-type first core 101 includes a body portion 112, both outer leg portions 114 a and 114 b that extend upward from the body portion 112, and a middle leg portion 116.

  The coil 16 is wound from the lower end side of the middle leg portion 116 to the middle of the upper end side of the middle leg portion 116.

  As shown in FIG. 2, the one second core 102a is disposed between the inner surface of the one outer leg portion 114a and the opposing surface of the middle leg portion 116 and on the upper surface side of the coil 16, and The leg 114 a and the middle leg 116 are magnetically connected via the magnetic gaps 121 and 122.

  Similarly, the other second core 102b is disposed between the inner surface of the other outer leg portion 114b and the facing surface of the middle leg portion 116 and on the upper surface side of the coil 16, and the other outer leg portion 114b. The middle leg 116 is magnetically connected via the magnetic gaps 123 and 124.

  Here, the main magnetic flux φc formed in the reactor main body 12 by the coil 16 will be described.

  4A is a plan view of the reactor 10, FIG. 4B is a cross-sectional view of the reactor 10 taken along line IVB-IVB, and FIG. 4C is a cross-sectional view of the reactor 10 taken along line IVC-IVC.

  FIG. 5 is an explanatory diagram in which the main magnetic flux φc is drawn on the IVB-IVB line cross-sectional view of the reactor 10 of FIG. 4B.

  As shown in FIG. 5, the main magnetic flux φc is a closed magnetic circuit drawn on the left side in FIG. 5 (from the body portion 112 of the E-type first core 101 to one outer leg portion 114 a, the magnetic air gap 121, A path that returns to the body 112 through the second core 102a, the magnetic gap 122, and the middle leg 116), and a closed magnetic circuit drawn on the right side (from the body 112 of the E-type first core 101 to the other outer leg). 114 b, the magnetic gap 124, the other second core 102 b, the magnetic gap 123, and a path that returns to the trunk portion 112 through the middle leg portion 116).

  As described with reference to FIG. 5, the main magnetic flux φc is formed in the reactor 10 by the coil 16. The magnets 201a, 201b, 301a, 301b do not exist in the closed magnetic path formed by the main magnetic flux φc.

  Next, as shown in FIG. 3, the first and second bias magnetic flux generators 21 and 22 have both outer legs 114 a and 114 b and middle legs in the space inside the virtual circumscribed rectangular parallelepiped 14 surrounding the reactor body 12. Each of the portions 116 is disposed adjacent to the front side and the back side of the upper end side and on the upper surface side of the coil 16.

  The first bias magnetic flux generation unit 21 is provided inside the outer I-type third cores 103a and 103b that are magnetically connected to the outer legs 114a and 114b, and the outer third cores 103a and 103b. As will be described later, I-type first and second magnets 201a and 201b that generate a bias magnetic flux φm opposite to the main magnetic flux φc generated by the coil 16, and the first and second magnets 201a. , 201b and a central I-type third core 103c disposed between the two central members 201b.

  Similarly, the second bias magnetic flux generator 22 includes both outer I-type third cores 203a and 203b that are magnetically connected to the outer legs 114a and 114b, and the outer third cores 203a and 203b. The first and second I-type magnets 301a and 301b, which generate a bias magnetic flux φm opposite to the main magnetic flux φc generated by the coil 16, as will be described later, The central I-type third core 203c disposed between the two magnets 301a and 301b is coaxially disposed.

  Here, the bias magnetic fluxes φm1 (φm1a, φm1b) and φm2 (φm2a, φm2b) formed by the first and second bias magnetic flux generators 21 and 22 will be described in detail.

  For convenience of understanding, the direction parallel to the body 112 of the E-shaped first core 101 is the x direction (x axis direction), and the direction parallel to the legs 114a, 114b, 116 is the z direction (z axis direction). , An orthogonal triaxial coordinate system in which the direction orthogonal to the xz plane is the y direction (y axis direction) is set.

  6A is a plan view of the reactor 10, FIG. 6B is a cross-sectional view of the reactor 10 taken along line IVB-IVB (hatching is omitted), and FIG. 6C is a cross-sectional view of the reactor 10 taken along line IVC-IVC (hatching is omitted). FIG. 6 is a schematic explanatory diagram depicting the main magnetic flux φc and the bias magnetic fluxes φm1 (φm1a, φm1b) and φm2 (φm2a, φm2b) formed by the first and second bias magnetic flux generation units 21 and 22, respectively.

  As shown in FIG. 6A, the bias magnetic flux φm1a indicated by the dotted line generated in the −x direction from the N pole of the first magnet 201a constituting the first bias magnetic flux generation unit 21 enters the third core 103a and the direction is the y direction. Then, it passes through the third core 103a and enters the outer leg portion 114a. The outer leg portion 114a is in the −z direction, and passes through the outer leg portion 114a and enters the trunk portion 112 as shown in FIG. 6B. As shown in FIG. 6A, the x direction is at the portion 112, the z direction is at the center of the torso portion 112, enters the middle leg portion 116 from the center portion of the torso portion 112, passes through the middle leg portion 116, and In the -y direction and enters the third core 103c. The direction of the third core 103c is changed to the -x direction and flows back to the S pole of the first magnet 201a.

  Hereinafter, since the other bias magnetic fluxes φm1b, φm2a, and φm2b can be understood in a similar manner, the bias magnetic fluxes generated in the x direction from the N poles of the remaining second magnets 201b constituting the first bias magnetic flux generator 21 will be briefly described. The magnetic flux φm1b returns to the S pole of the second magnet 201b through the paths shown in FIGS. 6A to 6C.

  Similarly, the magnetic flux φm2a generated in the −x direction from the N pole of the first magnet 301a constituting the second bias magnetic flux generation unit 22 passes through the path shown in FIGS. 6A to 6C to the S pole of the first magnet 301a. The magnetic flux φm2b generated in the x direction from the N pole of the remaining second magnet 301b constituting the second bias magnetic flux generation unit 22 returns and passes through the path shown in FIGS. 6A to 6C, and the S of the second magnet 301b. Return to the pole.

  6A to 6C, the path indicated by the solid line through which the main magnetic flux φc flows is as described with reference to FIG. 5.

  As can be understood from FIGS. 6A to 6C, the E-type first core 101 and the I-type second core 102 a and the I-type second cores 102 a and 102 b flow in the main magnetic flux φc. The flow of the bias magnetic fluxes φm1a, φm2a, φm1b, and φm2b flowing through the second cores 102a and 102b of the mold cancels because they are in opposite directions. As a result, since the magnetic flux in the first core 101 and the second cores 102a and 102b is not easily saturated, the magnetic flux density in the reactor 10 is reduced, so that the cross-sectional area of the core can be reduced and the volume of the reactor 10 can be reduced. Can be

  Since the magnets 201a, 201b, 301a, 301b are provided outside the window formed by the E-type first core 101 and the I-type second cores 102a, 102b, the number of turns of the coil 16 can be increased. The inductance can be increased.

  Moreover, since the main magnetic flux φc does not flow through the magnets 201a, 201b, 301a, 301b constituting the first and second bias magnetic flux generators 21, 22, the magnets 201a, 201b, 301a, 301b is not demagnetized.

  In addition, the magnet length that is the length in the x direction of the magnets 201a, 201b, 301a, and 301b is the magnetic length that is the length in the x direction of the magnetic gaps 121, 122, 123, and 124. The magnetic bias effect can be enhanced because the magnetic air gap length << magnet length relationship. Since the magnet length is long and the magnetic resistance becomes high, the main magnetic flux φc is more difficult to pass through the magnets 201a, 201b, 301a, and 301b than in the prior art.

  As described above, the reactor 10 according to the first embodiment includes the E-type first core 101 having the trunk portion 112, the outer leg portions 114 a and 114 b extending upward from the trunk portion 112, and the middle leg portion 116. The coil 16 wound from the lower end side to the middle of the upper end side of the middle leg portion 116, and between the inner side surface of one outer leg portion 114a and the opposing surface of the middle leg portion 116 and on the upper surface side of the coil 16 One I-type second core 102a that is disposed and magnetically connects one outer leg portion 114a and the middle leg portion 116, the inner side surface of the other outer leg portion 114b, and the opposite surface of the middle leg portion 116 A reactor main body portion 12 having an I-type second core 102b that is magnetically connected between the other outer leg portion 114b and the middle leg portion 116. In the virtual circumscribed rectangular parallelepiped 14 surrounding the reactor body 12 The first and second bias magnetic flux generators 21 are disposed adjacent to the front and back sides of the upper ends of the outer legs 114 a and the middle legs 116 and on the upper surface side of the coil 16. , 22.

  Here, the first bias magnetic flux generator 21 includes both outer I-type third cores 103a and 103b that are magnetically connected to the outer legs 114a and 114b, and the outer third cores 103a and 103b. Between the first magnets 201a and 201b and I-type first magnets 201a and 201b that generate a bias magnetic flux φm1 (φm1a and φm1b) opposite to the main magnetic flux φc generated by the coil 16. The central I-type third core 103c to be arranged is arranged coaxially.

  Similarly, the second bias magnetic flux generator 22 includes both outer I-type third cores 203a and 203b that are magnetically connected to the outer legs 114a and 114b, and the outer third cores 203a and 203b. I-type first and second magnets 301a and 301b that generate a bias magnetic flux φm2 (φm2a and φm2b) opposite to the main magnetic flux φc generated by the coil 16 and the first and second magnets. A central I-type third core 203c disposed between the magnets 301a and 301b is coaxially disposed.

  According to the reactor 10 according to the first embodiment, in the space in the virtual circumscribed rectangular parallelepiped 14 surrounding the reactor main body 12, the outer leg portions 114a and 114b and the upper end side of the middle leg portion 116 are disposed on the front side and the back side. Bias magnetic fluxes φm1 (φm1a, φm1b), φm2 (φm2a) adjacent to each other and on the upper surface side of the coil 16 and opposite to the main magnetic flux φc generated by the coil 16 using the magnets 201a, 201b, 301a, 301b. , [Phi] m2b), the first and second bias magnetic flux generators 21 and 22 are provided, so that the reactor 10 has a small volume (small size), but the magnet lengths of the magnets 201a, 201b, 301a, and 301b are small. Can be lengthened.

  In other words, the virtual circumscribed cuboid 14 has the size of a case that accommodates the reactor 10, and a bias magnetic flux is generated in a dead space (a space that cannot be used) formed when the reactor main body 12 is accommodated in this case. Since the parts 21 and 22 are accommodated, it is possible to create the reactor 10 that prevents an increase in the size of the reactor 10 while ensuring a sufficient magnet length.

  FIG. 7 is an exploded perspective view of the reactor 10A according to the inner iron type second embodiment using the U-shaped first core 101A, FIG. 8 is a perspective view of the reactor main body 12A constituting the reactor 10A, and FIG. These are perspective views of reactor 10A. The configuration and operation of the inner iron type reactor 10A according to the second embodiment are basically the same as the configuration and operation of the outer iron type reactor 10 according to the first embodiment described above. explain.

  A reactor 10A according to the second embodiment is basically a reactor main body 12A shown in FIG. 8 and a virtual circumscribed rectangular parallelepiped 14A shown by a two-dot chain line circumscribing the reactor main body 12A (see FIGS. 8 and 9). The bias magnetic flux generator 21A (see FIGS. 7 and 9) is disposed in the space.

  As shown in FIG. 8, the reactor body 12A is composed of a U-shaped first core 101A, square cylindrical coils 16A and 16B that generate a main magnetic flux φc, which will be described later, and an I-type second core 102A. Is done. In addition, each core is comprised by laminating | stacking a steel plate, for example.

  The U-shaped first core 101A includes a trunk portion 112A and both outer leg portions 114A and 114B extending upward from the trunk portion 112A.

  The coils 16A and 16B are wound from the lower end side of the outer leg portions 114A and 114B to the middle of the upper end side.

  The second core 102A is disposed between the outer leg portions 114A and 114B and on the upper surface side adjacent to the coils 16A and 16B, and the outer leg portion 114A and the outer leg portion 114Ba are magnetized via the magnetic gaps 121A and 121B. Connect.

  The bias magnetic flux generator 21A is disposed in a space inside the virtual circumscribed cuboid 14A surrounding the reactor main body 12A as a quadrangular ring shape, and is magnetically connected to both outer side surfaces of both outer legs 114A and 114B. The I-type third cores 103A and 103B, which are arranged to extend on the upper surfaces of the coils 16A and 16B, and between both ends of the opposing surfaces of the third cores 103A and 103B and on the upper surfaces of the coils 16A and 16B. I-type first and second magnets 201A and 301A that generate bias magnetic fluxes φm1 and φm2 in opposite directions, as will be described later, with respect to the main magnetic flux φc that is disposed along the coils 16A and 16B, respectively. Have

  10A, FIG. 10B, and FIG. 10C are drawings for clarifying the configuration of the reactor 10A of the second embodiment, FIG. 10A is a plan view of the reactor 10A, and FIG. 10B is XB-XB of the reactor 10A. FIG. 10C is a sectional view taken along line XC-XC of reactor 10A.

  Next, the main magnetic flux φc formed by the coils 16A and 16B and the bias magnetic fluxes φm1 and φm2 formed by the bias magnetic flux generator 21A will be described.

  Also in this second embodiment, for convenience of understanding, the direction parallel to the trunk portion 112A of the U-shaped first core 101A is the x direction (x axis direction), and the direction parallel to the legs 114A and 114B is z. An orthogonal triaxial coordinate system is set in which the direction (z-axis direction) and the direction orthogonal to the xz plane are the y-direction (y-axis direction).

  11A is a plan view of reactor 10A, FIG. 11B is a cross-sectional view of reactor 10A taken along line XB-XB (hatching is omitted), and FIG. 11C is a cross-sectional view of reactor 10A taken along line XC-XC (hatching is omitted). FIG. 7 is a schematic explanatory diagram depicting the main magnetic flux φc and the bias magnetic fluxes φm1 and φm2 formed by the bias magnetic flux generation unit 21A, respectively.

  As shown in FIGS. 11A to 11C, the main magnetic flux φc indicated by a solid line is from the trunk portion 112A of the U-shaped first core 101A to one leg portion 114A, the magnetic air gap 121A, the second core 102A, and the magnetic air gap 121B. And a closed magnetic path that returns to the trunk portion 112A through the leg portion 114B.

  In this case, the main magnetic flux φc is formed in the reactor 10A by the coils 16A and 16B. The magnets 201A and 301A are not present in the closed magnetic path formed by the main magnetic flux φc.

  Among the bias magnetic fluxes φm1 and φm2 indicated by the dotted lines, the bias magnetic flux φm1 is generated in the −x direction from the N pole of the first magnet 201A constituting the bias magnetic flux generating unit 21, as shown in FIG. 11A. The bias magnetic flux φm1 generated in the −x direction enters one third core 103A, the direction is changed from the −x direction to the y direction, and is further changed to the −x direction at the intermediate portion of the third core 103A. It enters the upper end side, and is set to the −z direction on the upper end side of the leg portion 114A. As shown in FIG. 11B, the direction passes through the leg portion 114A and enters the trunk portion 112A, and the direction is set to the x direction. 11A and enters leg portion 114B. As shown in FIGS. 11B and 11C, the y-direction of leg portion 114B passes through leg portion 114B, and the upper end side of leg portion 114B is shown in FIG. 11A. Thus, the x direction is entered into the other third core 103B, the direction is the -y direction, the third core 103B is passed through, and the -x direction is set by the first magnet 201A, and the S of the first magnet 201A It flows to return to the pole.

  Since the other bias magnetic flux φm2 can be understood in the same manner, the bias magnetic flux φm2 generated in the x direction from the N pole of the remaining second magnet 301A constituting the bias magnetic flux generator 21A will be briefly described. It returns to the south pole of the 2nd magnet 301A through the course shown in.

  As understood from FIGS. 11A to 11C, the bias magnetic flux flowing in the U-shaped first core 101A with respect to the flow of the main magnetic flux φc flowing in the U-shaped first core 101A and the I-type second core 102A. Since the flows of φm1 and φm2 are in opposite directions, they cancel out. As a result, since the magnetic flux of the first core 101A is not easily saturated, the magnetic flux density in the reactor 10A is reduced, so that the cross-sectional area of the core can be reduced and the volume of the reactor 10A can be reduced.

  Since the first and second magnets 201A and 301A are provided outside the window formed by the U-shaped first core 101A and the I-type second core 102A, the number of turns of the coils 16A and 16B can be increased. Inductance can be increased.

  In addition, since the main magnetic flux φc does not flow through the first and second magnets 201A and 301A constituting the bias magnetic flux generator 21A, the first and second magnets 201A and 301A are demagnetized. There is nothing.

  In addition, the magnetic gap that is the length of the first and second magnets 201A and 301A in the x direction is smaller than the magnetic gap that is the length of the magnetic gaps 121A and 121B in the x direction. Since the configuration is such that the length << the magnet length, the magnetic bias effect can be enhanced. Since the magnet length is long and the magnetic resistance is high, the main magnetic flux φc is less likely to pass through the first and second magnets 201A and 301A as compared with the prior art.

  As described above, the reactor 10A according to the second embodiment includes the U-shaped first core 101A having the trunk portion 112A and both outer leg portions 114A and 114B extending upward from the trunk portion 112A, and both outer legs. The coils 16A and 16B wound from the lower end side of the portions 114A and 114B to the middle of the upper end side and the inner side surfaces of the outer leg portions 114A and 114B and on the upper surface side of the coils 16A and 16B, the both leg portions 114A , 114B magnetically connecting the I-type second core 102A, and the outer leg portions 114A and 114B in the space inside the virtual circumscribed cuboid 14A surrounding the reactor main body portion 12A. The coils 16A and 16B are generated using the magnets 201A and 301A, adjacent to the periphery of the upper end side of the coil 16A and on the upper surface side of the coils 16A and 16B. And a bias magnetic flux generating unit 21A for generating reverse bias flux Fai1m, the φ2m against bundle .phi.c.

  Here, the bias magnetic flux generating portion 21A is magnetically connected to both outer side surfaces of both outer leg portions 114A and 114B, and both I-type third cores 103A arranged along the upper surfaces of the coils 16A and 16B. 103B and the opposite ends of the third cores 103A and 103B and along the upper surfaces of the coils 16A and 16B, and a bias opposite to the main magnetic flux φc generated by the coils 16A and 16B, respectively. The magnetic fluxes φ1m and φ2m are generated.

  According to the reactor 10A according to the second embodiment, in the space inside the virtual circumscribed rectangular parallelepiped 14 surrounding the reactor main body 12, the coil 16A is adjacent to the periphery of each of the outer leg portions 114A and 114B. , 16B, and is configured to include a bias magnetic flux generator 21A that generates bias magnetic fluxes φm1 and φm2 opposite to the main magnetic flux φc generated by the coils 16A and 16B using the magnets 201A and 301A. Therefore, although the reactor 10A has a small volume (small size), the magnet lengths of the magnets 201A and 301A can be increased.

  In other words, the virtual circumscribed cuboid 14A has the size of a case that accommodates the reactor 10A, and a bias magnetic flux is generated in a dead space (a space that cannot be used) formed when the reactor main body 12A is accommodated in this case. Since the portion 21A is accommodated, it is possible to create the reactor 10A that prevents an increase in the size of the reactor 10A while ensuring a sufficient magnet length.

  Note that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted based on the contents described in this specification.

DESCRIPTION OF SYMBOLS 10, 10A ... Reactor 12, 12A ... Reactor main-body part 14, 14A ... Virtual circumscribed rectangular parallelepiped 16, 16A, 16B ... Coil 21, 22, 21A ... Bias magnetic flux generation part 101, 101A ... 1st core 102a, 102b, 102A ... 1st 2 cores 103a, 103b, 103c, 203a, 203b, 203c, 103A, 103B ... 3rd cores 112, 112A ... trunks 114a, 114b, 116, 114A, 114B ... legs 201a, 201b, 301a, 301b, 201A, 301A …magnet

Claims (2)

An E-type first core having a trunk, and both outer and middle legs extending upward from the trunk;
A coil wound to the upper end side midway from the lower side in said leg portion,
One that is disposed between the inner side surface of the one outer leg portion and the opposing surface of the middle leg portion and on the upper surface side of the coil, and magnetically connects the one outer leg portion and the middle leg portion. Between the inner surface of the other outer leg portion and the opposing surface of the middle leg portion and on the upper surface side of the coil, and the other outer leg portion and the middle leg portion. The other second core to be magnetically connected;
A reactor body having
During space within the virtual circumscribing rectangular parallelepiped surrounding the reactor main body, adjacent to the front side and the back side of the upper end side in said leg portion and said Ryosotoashi portion, Ru is and disposed on the upper surface side of the coil first When configured bias magnetic flux generating unit 1 and the second bias flux generating section,
Equipped with a,
The first and second bias magnetic flux generators are
Each of the outer third cores magnetically connected to the outer legs, and a bias magnetic flux opposite to the main magnetic flux generated by the coil disposed inside the outer third cores. The generated first and second magnets and the central third core arranged between the first and second magnets are arranged coaxially.
Reactor characterized that you have been configured. A U-shaped first core having a trunk portion and both outer legs extending upward from the trunk portion;
A coil wound to the upper end side midway from the lower side of the both outer legs,
Wherein both outer disposed on an upper surface side of and the coil between the inner surfaces of the legs, and the second core that connects between the both outer legs magnetically,
A reactor body having
A bias magnetic flux generator,
With
The bias magnetic flux generator is
Both third cores that are magnetically connected to both outer surface sides of the outer leg portions and disposed along the upper surface of the coil in a space in a virtual circumscribed cuboid that surrounds the reactor main body, First and second magnets that are disposed between opposite ends of both third cores and along the upper surface of the coil, and generate a bias magnetic flux that is opposite to the main magnetic flux generated by the coil,
Reactor and wherein the Rukoto to have a.

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