JP2011159851A - Reactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reactor having inexpensive constitution by minimizing reactor loss on the whole although using an expensive core material for a leg portion material. <P>SOLUTION: The reactor includes a pair of opposed yoke portions and three or more leg portions disposed between the pair of opposed yoke portions, and uses a material having lower loss than a material constituting two side leg portions positioned on both yoke portion sides among those leg portions as a material of at least one leg portion (specific leg portion) among other leg portions except the two side leg portions, wherein a coil is wound at least around the specific leg portion. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a reactor which is a passive element that alternately stores and releases magnetic energy, and this reactor is a reactor including a core (magnetic core) and a coil wound around the core. .

  For example, the reactor includes, as a magnetic circuit, a pair of opposing yoke parts and a leg set composed of a plurality of legs arranged between the yoke parts, and between the opposing of the yoke part and the leg set. In addition, there is a configuration in which a non-magnetic insulator is interposed between opposing legs in a leg set to provide a magnetic gap, and a coil is wound around these legs.

  For example, in a hybrid vehicle, a plug-in hybrid vehicle, and an electric vehicle, a boost converter for increasing the output of the motor is necessary as an application of such a reactor. In such a boost converter, a reactor that charges and discharges energy is essential. It is a part. Also, in a solar power generation system or the like, a reactor is an essential basic component for smoothing the converted output after DC / DC conversion and then DC / AC conversion of the solar cell output.

Japanese Patent Laid-Open No. 11-40434 JP 2009-71248 A

  In such a reactor, it is desirable to reduce the loss in the magnetic circuit composed of the yoke part and the leg part set as much as possible and to improve the performance. For this reason, in Patent Document 1, the shape of the yoke portion is made into a “U” shape of Katakana, and in Patent Document 2, a magnetic gap is provided between the leg portions and a dust core is used as a core material. By the way, a reactor is generally used for smoothing a pulsating flow obtained by rectifying an alternating current by providing a magnetic gap so that magnetic saturation hardly occurs. Therefore, conventionally, a magnetic gap is provided between the yoke part and the leg part or between the leg parts.

  Here, the reactor loss mainly includes a loss due to the coil (copper loss) and a loss due to the core (iron loss). The copper loss is a loss due to the DC resistance loss, the AC resistance loss, and the leakage flux of the core interlinking with the coil. Iron loss includes hysteresis loss and eddy current loss.

  In order to reduce the reactor loss, it is conceivable to use a low-loss core material as the core material. However, since such a material is generally expensive, it is one of the factors that increase the cost of the reactor. Therefore, there is a problem that it becomes a reactor unsuitable for mass production. On the other hand, although a general-purpose core material is inexpensive, there is a problem that reactor loss increases.

  Therefore, in the present invention, it is an object to be solved to provide a reactor having a structure capable of effectively suppressing reactor loss by utilizing the advantages of the low-loss core material and the general-purpose core material.

  A reactor according to the present invention includes a pair of opposing yoke portions and a leg set disposed between the pair of opposing yoke portions, and the leg set is configured by three or more leg portions, Of these legs, a general-purpose core material is used as the core material of the two side legs located on the side of both yoke parts, while the core material of the center leg sandwiched between both side legs is less than the general-purpose core material. A low-loss core material is used.

  In the present invention, since the low-loss core material is used for the material of the legs excluding the side legs, the loss is somewhat larger than when a material with a large loss is used for all the legs, but more than this. While the price can be made sufficiently low, the loss can be minimized as compared with other combinations of materials, and at the same time, the price can be reduced.

  A preferred embodiment is to provide a magnetic gap between the side leg portion and the yoke portion.

  In a more preferred embodiment, a dust core is used for the yoke part and the leg part, a Fe-Si based material is used for the material of the yoke part and the side leg part, and a Fe-Ni based or Mo material is used for the material of the specific leg part. Permalloy (Fe-Ni-Mo system) or amorphous system is used.

  In a more preferred embodiment, a dust core is used for the yoke part and the leg part, a ferrite core is used for the material of the yoke part, a Fe-Si based material is used for the material of the side leg part, and the material of the specific leg part In addition, Fe—Ni, Mo permalloy (Fe—Ni—Mo) or amorphous is used.

  ADVANTAGE OF THE INVENTION According to this invention, the reactor provided with the structure which can suppress a reactor loss with an inexpensive structure can be provided.

FIG. 1 is a diagram showing a side configuration of a reactor according to an embodiment of the present invention. FIG. 2 is a diagram showing an external configuration in the absence of the reactor coil. 3A shows a reactor using a low-loss core material for one side leg shown by hatching, FIG. 3B shows a reactor using a low-loss core material for both side legs shown by hatching, FIG. ) Is a view showing a reactor using a low-loss core material for a center leg portion indicated by hatching. FIG. 4 is a diagram showing the loss characteristics of the reactors A, B, and C in FIGS. 3 (a), 3 (b), and 3 (c). 5A, 5B, and 5C are views showing reactors having various configurations. FIG. 6 is a view showing a side configuration of a reactor according to another embodiment of the present invention. FIG. 7 is a view showing a side configuration of a reactor according to still another embodiment of the present invention.

  Hereinafter, a reactor according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  First, referring to FIG. 1 and FIG. 2, a reactor 10 according to the present embodiment includes a pair of flat yoke portions 11a and 11b facing each other in parallel and between both sides of the pair of facing yoke portions 11a and 11b. It includes leg sets 12, 13 arranged on each. One leg set 12 has a structure in which three leg parts 12a, 12b, 12c each having a quadrangular prism block shape of the same size are laminated without a magnetic gap, and the other leg set 13 is the same as described above. All of them have a configuration in which three leg portions 13a, 13b, and 13c having a quadrangular prism block shape having the same size are stacked without a magnetic gap. Coils 14 and 15 are wound around these leg portions 12 and 13 as indicated by broken lines. The leg shape is not limited to the rectangular block shape, and may be a cylindrical block shape. Of course, the leg portions of the leg sets 12 and 13 are laminated without any gap therebetween, but may be bonded in such a manner that no magnetic gap is interposed therebetween.

  Magnetic gap 16a between the yoke part 11a and one leg part set 12, magnetic gap 16b between the yoke part 11b and one leg part set 12, and between the yoke part 11a and the other leg part set 13 A magnetic gap 17 b is provided between the magnetic gap 17 a and the yoke portion 11 b and the other leg set 13. It is preferable that the above-described magnetic gap interval can be adjusted as appropriate.

  In each leg set 12, 13, for convenience of explanation, the leg portions 12a, 12c near the yoke portions 11a, 11b; 13a, 13c are referred to as side leg portions, and the central leg portions 12b, 13b are center leg portions. Part. Of course, in the above description, the number of the leg portions sandwiched between the side leg portions 12a and 12c; 13a and 13c is one. It shall be called.

  In the reactor 10 of the embodiment having the above configuration, a ferrite core is used as the material of the yoke portions 11a and 11b, a general-purpose core material is used as the material of the side leg portions 12a and 12c; A low-loss core material is used for 12b and 13b. The loss of general purpose core material is greater than that of low loss core material, but the core material price is cheaper than low loss core material. In the claims, the center legs 12b and 13b using the low-loss core material are the specific legs. Then, in reactor 10 of the embodiment, the number of specific legs is one for each leg set.

  “Loss” in the above-mentioned low-loss core material and general-purpose core material can be defined as iron loss. In the following Q value, the total of all losses including copper loss and iron loss is R, and the inductance of the reactor is If L and the frequency are f, it can be defined as ωL / R = 2πfL / R, and the Q value increases as the loss decreases.

  In the embodiment, the general-purpose core material is, for example, an Fe—Si based dust core, and the low loss core material is, for example, an Fe—Ni based, Mo permalloy (Fe—Ni—Mo based), or an amorphous based dust core. . Of course, the general-purpose core material and the low-loss core material are not limited to the above examples.

  In the reactor using the low-loss core material for all of the side legs 12a, 12c; 13a, 13c and the center legs 12b, 13b, naturally, the loss is low but the cost is considerably high. 12a, 12c; 13a, 13c, and the center leg portions 12b, 13b are all reactors using a general-purpose core material.

  Therefore, in the present embodiment, one center leg portion sandwiched between both side leg portions 12a, 12c; 13a, 13c of both leg portion sets 12, 13 and both side leg portions 12a, 12c; 13a, 13c. A general-purpose core material and a low-loss core material are commonly used for 12b and 13b, and the shared form has a special form.

  In other words, in the present embodiment, a general-purpose core material is used for both side leg portions 12a and 12c; 13a and 13c of both leg sets 12 and 13, while sandwiched between both side leg portions 12a and 12c; 13a and 13c. By using a low-loss core material for each of the center leg portions 12b and 13b, the reactor configuration is minimized among the above-mentioned common types while minimizing the cost while minimizing the loss.

  The reactor 10 of such an embodiment is a reactor in which center leg portions 12b and 13b of both leg portion sets 12 and 13 and both side leg portions 12a and 12c; 13a and 13c made of a general-purpose core material are mixed. The reactor of the embodiment using the leg portion in which the core material is mixed and other reactors will be described with reference to FIGS. 3 and 4.

  3 and 4, the reactors A, B, and C are used for convenience of explanation, and the reactor 10 of the embodiment corresponds to the reactor C. Reactor A includes yoke parts A1 and A2, and leg part sets A3 and A4. Reactor B includes yoke parts B1 and B2 and leg part sets B3 and B4. Reactor C includes yoke parts C1 and C2 and leg part set C3. Includes C4.

  In the reactor A of FIG. 3 (a), a low-loss core material is used for one side leg (shown by hatching) of each of the leg sets A3, A4, and the reactor B of FIG. A low-loss core material is used for both side legs (shown by hatching) of each of B4, and the reactor C in FIG. 3 (c) has low loss at the center leg (shown by hatching) of each of the leg sets C3 and C4. A core material is used.

  FIG. 4 is a diagram showing the loss characteristics of the reactors A, B, and C in FIGS. 3 (a), 3 (b), and 3 (c). Fe-Ni dust core is used as a low-loss core material. Fe-Si based dust core is used as a general-purpose core material. The yoke portions 11a and 11b are Mn ferrite cores.

  FIG. 4 shows the Q values of the reactors A, B, and C, respectively. In FIG. 4, the horizontal axis indicates reactors A, B, and C, and the vertical axis indicates the Q values of the reactors A, B, and C.

  The loss curve L1 has a Q value measurement frequency of 15 kHz (Q15), and the loss curve L2 has a Q value measurement frequency of 20 kHz (Q20).

  This measurement frequency is the frequency of the measuring instrument that measures the Q value.

  As a method for measuring the Q value, for example, an LCR meter 4284A manufactured by hp is used, and the terminal of the reactor whose Q value is to be measured is connected to the terminal of the LCR meter.

  Next, the measurement frequency of the LCR meter was set to 15 kHz or 20 kHz, the measurement voltage was set to 1 V or the measurement current was set to 10 mA, and the Q value at that time was read.

  In the loss curves L1 and L2, in reactor A, Q15 is 59.1, Q20 is 63.5, reactor B is Q15 in 66.7, Q20 is 72.4, reactor C is Q15 in 70.2, Q20 is 73. 4. From these, since the Q value of the reactor C of the embodiment is larger than that of the other reactors A and B, it is clear that the loss is minimum.

  As described above, in the reactor of the present embodiment, the pair of opposing yoke portions 11a and 11b, the side leg portions 12a and 12c; 13a and 13c, and the center leg portion between the pair of opposing yoke portions 11a and 11b. 12b and 13b, and the center leg portions 12b and 13b excluding the side leg portions 12a and 12c; 13a and 13c are specified leg portions, and the side leg portions 12a and 12c; Since a material with a lower loss than the core material is used, the loss is slightly larger than when using a material with low loss for all legs, but the price can be made sufficiently lower than this. On the other hand, the loss can be minimized as compared with other combinations of materials, and at the same time, the price is low.

  The present invention is not limited to the reactor shown in FIGS. 1 and 2, and may be, for example, the configuration of the reactor 20 shown in FIG. The reactor 20 includes yoke portions 21a and 21b and leg portion sets 22 and 23, and a magnetic gap 25a between the yoke portions 21a and 21b and the leg portion sets 22 and 23 as in the above embodiment. , 25b, 26a, 26b, but magnetic gaps 29a, 29b, 30a, 30b are also provided between the leg portions 22a-22c; 23a-23c constituting the leg sets 22, 23. In the reactor 20, since the magnetic gap can be dispersed and the magnetic gap can be provided in the coil, the leakage of the magnetic flux can be reduced, and the loss can be reduced by reducing the magnetic flux linked to the coil. This has the effect of improving the inductance superposition characteristics.

  Note that the number of specific legs in the reactor 20 in FIG. 5A is one for each leg set, and the number of specific legs in the reactor 30 in FIG. 5B is for each leg set. The number of specific legs in the reactor 40 in FIG. 5C is 1 for one leg set and 2 for the other leg set. The number of legs constituting the leg set may be three or more, and the reactor 30 in FIG. 5B has four legs constituting the leg set. In the reactor 40 in FIG. The number of legs is five. Further, the number of legs may be larger than this. Reactor 30 includes yoke portions 31a and 31b, a leg set 32 including leg portions 32a to 32d, and a leg portion 33 including leg portions 33a to 33d, and yoke portions 31a and 31b and a leg set 32. , 33 are provided with magnetic gaps 34a, 34b, 35a, 35b as in the above embodiment. Reactor 40 includes yoke portions 41a and 41b, a leg set 42 including leg portions 42a to 42e, and a leg portion 43 including leg portions 43a to 43e, and includes yoke portions 41a and 41b and a leg set 42. , 43 are provided with magnetic gaps 44a, 44b, 45a, 45b as in the above embodiment.

  Further, the leg portion of the low-loss core material may be a center leg portion, and in the reactor 30 of FIG. 5B, each leg set 32, 33 has a leg portion 32b, 32c, 33b, 33c as a center leg portion. However, a low-loss core material may be used for all of these center legs. Also. In the reactor 40 of FIG. 5C, in one leg set 42, two of the three center legs 42b-42d have low-loss core material, and the other leg set 43 has three center legs 43b- A low loss core material may be used for one of 43d.

  Note that silicon steel having a Si content of approximately 6.5% can be used as the low-loss core material, and silicon steel having a Si content of less than 6.5% can be used as the general-purpose core material. Silicon steel containing 6.5% Si is a core that achieves low noise, low loss, and high magnetic permeability.

  As described above, in the present embodiment, since the low-loss core material is used as the material of the legs excluding the side legs, there is a slight loss compared to the case where a material with a small loss is used for all the legs. Although it becomes larger, the price can be made sufficiently lower than this, while the loss can be suppressed to a minimum as compared with other combinations of materials and at the same time the price can be reduced.

  In the embodiment, the magnetic circuit has a katakana “ro” shape, but is not limited to this. For example, as shown by a reactor 50 in FIG. In addition, a leg set 52 including side leg parts 52a and 52c and a center leg part 52b is put into a “day” shape, and a low-loss core material is used for the center leg part 52b in the leg part set 52. It is good also as a structure which wound the coil 53, and it is good to use a low-loss core material for the leg part which becomes a center leg part similarly in another shape. Reference numerals 52d and 52e denote magnetic gaps.

  Further, as shown by a reactor 60 in FIG. 7, between the yoke portions 61a and 61b, one leg set 62 (consisting of side leg portions 62a and 62c and a center leg portion 62b) and the other leg set 63 (side Of the leg portions 63a and 63c and the center leg portion 63b), for example, a low-loss core material is used only for the center leg portion 62b in the leg set 62 on one side, and a center using the low-loss core material is used. It is good also as a structure which winds the coil 64 at the leg part set 62 side which has the leg part 62b.

10 Reactor 11a, 11b Yoke part 12 Leg part set 12a, 12c Side leg part 12b Center leg part 13 Leg part set 13a, 13c Side leg part 13b Center leg part

Claims (5)

  A pair of opposing yoke portions and a leg set disposed between the pair of opposing yoke portions, wherein the leg set is composed of three or more leg portions, A general-purpose core material is used as the core material of the two side legs located on the yoke side, while a low-loss core material having a lower loss than the general-purpose core material is used as the core material of the center leg sandwiched between both side legs. A reactor characterized by being used and having a coil wound around at least a center leg.   The reactor according to claim 1, wherein a magnetic gap is provided between the side leg portion and the yoke portion.   A dust core is used for the yoke part and the leg part, a Fe-Si based material is used for the material of the yoke part and the side leg part, and a Fe-Ni based or Mo permalloy (Fe-Ni) is used for the material of the specific leg part. The reactor according to claim 1 or 2, wherein a -Mo) system or an amorphous system is used.   A dust core is used for the yoke part and the leg part, a ferrite core is used for the material of the yoke part, a Fe-Si based material is used for the material of the side leg part, and a Fe-Ni based material is used for the material of the specific leg part. Or the reactor of Claim 1 or 2 using the Mo permalloy (Fe-Ni-Mo) type | system | group or an amorphous type | system | group.   A pair of opposing yoke portions and a leg set disposed between the pair of opposing yoke portions, wherein the leg set is composed of three or more leg portions, A general-purpose core material is used as the core material of the two side legs located on the yoke side, while a low-loss core material having a lower loss than the general-purpose core material is used as the core material of the center leg sandwiched between both side legs. A reactor core that is characterized by being used.

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