Three-phase choke coil equipped with a vibration suppression system

Abstract

Three-phase choke coil comprising an outer circumferential iron core (20) surrounding the outer circumference and at least three iron core coils (31 to 33) that are in contact with or connected to the inner surface of the outer circumferential iron core, wherein the at least three iron core coils comprise iron cores (41 to 43) and coils wound around the iron cores (51 to 53), wherein a magnetically coupled gap (101 to 103) is formed between two adjacent iron cores, and which is further equipped with a vibration suppression assembly (60) which is arranged by a fixing element (65) at or near the intersection point of the slits and suppresses vibrations arising at the slits, wherein the fixing element (65) is arranged at least sectionally in at least one of the columns (101 to 103).

Description

Background of the invention 1. Field of the invention

[0001] The present invention relates to a three-phase reactor. 2. Description of the state of the art

[0002] It happens that oscillations occur during operation of a three-phase reactor, for example, a three-phase AC reactor. Since these oscillations generate noise and deteriorate the three-phase reactor, it is necessary to suppress the oscillations. The cause of such oscillations is the magnetic force acting between two iron cores that are opposite each other across a gap, or the magnetostriction of the iron cores of the reactor itself.

[0003] In patent application JP 2009-212384 A, the iron cores of the choke coil are fixed to a plate. Furthermore, patent application JP 2008-028288 A discloses arranging the choke coil in a housing and arranging leaf springs between the inner surface of the housing and the choke coil.

[0004] Other three-phase choke coils are known, for example, from US 2005 / 0 030 140 A1, DE 10 2017 101 156 A1, WO 2010 / 119 324 A2, and WO 2009 / 131 602 A1. A vibration-damped transformer is known, for example, from US 2012 / 0 146 758 A1. Brief description of the invention

[0005] However, the thicknesses of the inductors and the iron cores of each phase of the inductor vary depending on various manufacturing conditions and tolerances. Therefore, if the thicknesses of the iron cores of each phase are different, fixing the iron cores to a plate as in patent application JP 2009-212384 A is not sufficient, as the force becomes uneven.

[0006] Since the structure of patent application JP 2008 - 028 288 A requires a housing and leaf springs, there are problems such as increasing manufacturing costs and increasing overall dimensions.

[0007] The present invention has been made in view of these circumstances and has an object to provide a three-phase reactor which can be fixed regardless of thickness differences of the iron cores of the individual phases and in which vibrations are suppressed without an increase in manufacturing cost or an increase in dimensions.

[0008] The object is achieved according to the invention by a three-phase choke coil according to claim 1, according to claim 2 and according to claim 3.

[0009] A first aspect of the present invention relates to a three-phase reactor comprising an outer peripheral iron core surrounding the outer periphery and at least three iron core coils in contact with or connected to the inner surface of the outer peripheral iron core, wherein the at least three iron core coils comprise iron cores and coils wound around the iron cores, wherein a magnetically coupleable gap is formed between two mutually adjacent iron cores, and which is further provided with a vibration suppression structure arranged by a fixing element at an intersection point of the gaps or in the vicinity of the gaps and suppresses vibrations generated at the gaps, wherein the fixing element is arranged at least partially in at least one of the gaps.

[0010] A second aspect of the present invention relates to a three-phase reactor comprising an outer peripheral iron core surrounding the outer periphery and at least three iron core coils in contact with or connected to the inner surface of the outer peripheral iron core, wherein the at least three iron core coils comprise iron cores and coils wound around the iron cores, wherein a magnetically coupleable gap is formed between two mutually adjacent iron cores, and which is further provided with a vibration suppression structure arranged by a fixing element at an intersection point of the gaps or in the vicinity of the intersection point of the gaps and suppresses vibrations arising at the gaps, wherein the fixing element is arranged at least partially in at least one of the gaps, wherein the vibration suppression structure is arranged only at one end of the three-phase reactor in the layering direction of the iron cores.

[0011] A third aspect of the present invention relates to a three-phase reactor comprising an outer peripheral iron core surrounding the outer periphery and at least three iron core coils in contact with or connected to the inner surface of the outer peripheral iron core, wherein the at least three iron core coils comprise iron cores and coils wound around the iron cores, wherein a magnetically connectable gap is formed between two adjacent iron cores, and further provided with a vibration suppression structure disposed near the gaps and suppressing vibrations generated at the gaps, wherein the vibration suppression structure includes a vibration reducing element having an elastic structure and a fixing element for fixing the vibration reducing element to the iron cores, wherein the vibration reducing element includes at least three legs,which are to be inserted between two adjacent iron cores.

[0012] The vibration suppression structure is located at or near the intersection of the gaps. Therefore, the vibration suppression structure does not increase the size of the three-phase reactor, nor does it significantly increase manufacturing costs. Furthermore, the iron cores can be fixed regardless of the thickness of the iron cores of each phase.

[0013] These objects, features and advantages of the present invention as well as other objects, features and advantages will become more apparent from the detailed explanation of typical embodiments of the present invention shown in the accompanying drawings. Simple explanation of the drawings Fig. 1A is a plan view of a three-phase reactor based on the present invention. Fig. 1B is an oblique view of the Fig. 1A shown three-phase choke coil. Fig. 2 is a disassembled oblique view of the iron cores. Fig. 3 is an oblique view of the vibration suppression structure. Fig. 4 is a side view of a three-phase reactor based on another embodiment of the present invention. Fig. 5A is a side view of a three-phase reactor based on still another embodiment of the present invention. Fig. 5B is an oblique view of the Fig. 5A shown three-phase choke coil. Fig. 6A is a plan view of a vibration suppression structure in an additional embodiment. Fig. Figure 6B is a plan view of a three-phase reactor on which the Fig. 6A was installed. Fig. 6C is a disassembled oblique view of another choke coil in an additional embodiment. Fig. 7A is a disassembled oblique view of a choke coil in still another embodiment. Fig. 7B is an oblique view of the Fig. 7A shown choke coil. Fig. 7C is a modification of the Fig. 4 shown embodiment. Fig. 8 is a view showing a motor driving device incorporating the three-phase reactor of the present invention. Detailed explanation

[0014] Embodiments of the present invention will be explained below with reference to the accompanying drawings. In the following drawings, like components are designated by like reference numerals. For ease of understanding, the scale of these drawings has been changed arbitrarily.

[0015] Fig. 1A is a plan view of a three-phase reactor based on the present invention, and Fig. 1B is an oblique view of the Fig. 1A shown three-phase choke coil.

[0016] As in Fig. 1A and Fig. 1B, the three-phase reactor 5 comprises an outer peripheral iron core 20 and three iron core coils 31 to 33 that are mutually magnetically coupled to the outer peripheral iron core 20. In Fig. 1A, the iron core coils 31 to 33 are arranged on the inside of a hexagonally shaped outer peripheral iron core 20. The number of iron core coils may also be a multiple of three, which is greater than three.

[0017] As can be seen from the drawings, each of the iron core coils 31 to 33 includes an iron core 41 to 43 extending in the radial direction and a coil 51 to 53 wound around this iron core. The respective ends on the outside in the radial direction of the iron cores 41 to 43 are in contact with the outer peripheral iron core 20 or are formed integrally with the outer peripheral iron core 20.

[0018] Furthermore, the respective ends on the inside in the radial direction of the iron cores 41 to 43 are positioned near the center of the outer peripheral iron core 20. In Fig. 1A, etc., the respective inner ends in the radial direction of the iron cores 41 to 43 converge toward the center of the outer peripheral iron core 20, and their tip end angle is approximately 120 degrees. The inner ends in the radial direction of the iron cores 41 to 43 are separated from each other by magnetically connectable gaps 101 to 103.

[0019] In other words, the inner end in the radial direction of the iron core 41 and the respective inner ends in the radial direction of the iron cores 42, 43 are separated from each other by gaps 101, 102. The same applies to the other iron cores 42, 43. In the embodiments discussed later, the representation of gaps 101 to 103 may be omitted in some cases.

[0020] Thus, since the present invention eliminates the need for a center iron core positioned at the center of the three-phase reactor, the three-phase reactor can be constructed with a lightweight and simple structure. Furthermore, since the three iron core coils 31 to 33 are surrounded by the outer peripheral iron core 20, the magnetic fields generated by the coils 41 to 53 do not leak outside the outer peripheral iron core 20. Since the gaps 101 to 103 can be formed with any thickness at low cost, there are also advantages in designability compared with a reactor with a conventional structure.

[0021] Furthermore, in the three-phase reactor of the present invention, the difference in the magnetic path length between each phase is small compared to a reactor with a conventional structure. Therefore, the present invention can mitigate the inductance imbalance caused by the different magnetic path lengths.

[0022] Fig. 2 is a disassembled oblique view of the iron core. Fig. 2, the outer peripheral iron core 20 and the iron cores 41 to 43 are made in one piece. And as can be seen from Fig. As can be seen from FIG. 2, the outer peripheral iron core 20 and the iron cores 41 to 43 are formed by layering a plurality of plate-shaped magnetic materials, for example, electromagnetic steel plates. In this case, the manufacturing costs of the outer peripheral iron core 20 and the iron cores 41 to 43 can be reduced. The outer peripheral iron core 20 and the iron cores 41 to 43 can also be separately formed by layering a plurality of plate-shaped magnetic materials, for example, electromagnetic steel plates. The iron cores 41 to 43 do not need to be plate-shaped magnetic materials, but can also be core-shaped molded products made of a magnetic material.

[0023] When such a three-phase reactor 5 is operated, the iron cores 41 to 43 vibrate particularly in the vicinity of the gaps 101 to 103. If the iron cores 41 to 43 are formed separately from the outer peripheral iron core 20, these vibrations become even stronger.

[0024] As a measure against this problem, as Fig. 1A, a vibration suppression structure 60 is arranged in the center of the three-phase reactor 5 of the present invention. Fig. 3 is an oblique view of the vibration suppression structure. As shown in Fig. 3, the vibration suppression structure 60 includes a vibration reducing member 61 and a fixing member 65.

[0025] The vibration-reducing element 61 is an elastic structure or is formed from an elastic body, such as rubber. In other words, the vibration-reducing element 61 is preferably formed from a non-magnetic body. In this case, magnetic saturation can be suppressed because the magnetic permeability becomes low.

[0026] The vibration reducing element 61 has a central portion 62 and a plurality of, for example, three, extension portions 61a to 61c extending radially from the central portion 62 at equal intervals. The number of extension portions 61a to 61c is equal to or less than the number of gaps 101 to 103 of the three-phase reactor 5.

[0027] It is advantageous if the extension sections 61a to 61c extend obliquely with respect to the plane containing the central section 62. In other words, the extension sections 61a to 61c extend at a certain angle with respect to the central section 62. The fixing element 65 has a shape that can be inserted into an opening 63 of the central section 62, and for example, the fixing element 65 is a screw.

[0028] With further reference to Fig. 1A, the vibration suppression structure 60 is arranged in the center of the three-phase reactor 5. In other words, the vibration suppression structure 60 is arranged at or near the intersection point of the gaps 101 to 103. As can be seen from Fig. 1A, the extension portions 61a to 61c of the vibration reducing member 61 engage with the upper surface of the iron cores 41 to 43, respectively.

[0029] The fixing member 65 is passed through the opening 63 of the central portion 62, and the vibration reducing member 61 is pressed against the iron cores 41 to 43. As a result, the respective extension portions 61a to 61c of the shrinkage reducing member 61 deform and are positioned in the same plane as the central portion 62. As a result, the vibration reducing member 61 is fixed to the iron cores 41 to 43 by the fixing member 65. For this purpose, a male screw may also be used as the fixing member 65, and a thread (internal thread) that engages with the fixing member 65 may be formed at a position corresponding to the iron cores 41 to 43. An internal thread may also be formed on the fixing member 65, and an external thread may be formed at the position corresponding to the iron cores 41 to 43. This also applies to the embodiments discussed later.

[0030] In this way, the vibration suppression structure 60 in the present invention is configured to fix the iron cores 41 to 43. Therefore, vibrations can be suppressed during operation of the three-phase reactor, and consequently, noise generation and deterioration of the three-phase reactor can be prevented.

[0031] The vibration suppression structure 60 is arranged at or near the intersection point of the gaps 101 to 103. Therefore, the vibration suppression structure 60 does not cause the three-phase reactor 5 to become large in size, nor does it result in a sharp increase in manufacturing costs.

[0032] Since the vibration reducing member 61 has elasticity, it can fix the iron cores 41 to 43 regardless of the thickness of the iron cores 41 to 43 of each phase. Therefore, the work of attaching the vibration suppression structure becomes extremely easy.

[0033] Fig. 4 is a side view of a three-phase reactor based on another embodiment of the present invention. As shown in Fig. 4, it is advantageous to arrange a vibration reducing element 61 on each of the two end surfaces of the three-phase reactor 5. The vibration reducing elements 61 are fixed by fixing elements 65 as described above, but this is not possible in Fig. 4 is not shown. Therefore, it is advantageous to use two vibration suppression structures 60 for one three-phase choke coil 5. This allows the vibration suppression effect to be increased with a comparatively simple structure.

[0034] When an externally threaded screw is used as the fixing element 65 as described above and no thread is formed at the position corresponding to the iron cores 41 to 43 for screwing with the fixing element 65, fixing by a screw longer than the thickness of the iron cores and a nut 69 is also possible (see Fig. 6C).

[0035] Fig. 5A is a side view of a three-phase reactor based on yet another embodiment of the present invention, and Fig. 5B is an oblique view of the Fig. 5A. In the embodiment shown in Fig. 5A and Fig. As shown in FIG. 5B, a long rod 66 is inserted into the center of the three-phase reactor 5. More specifically, the rod 66 is inserted into the three-phase reactor 5 at a position corresponding to the intersection point of the columns 101 to 103. The length of the rod 66 is roughly equal to or slightly shorter than the length in the axial line direction of the three-phase reactor 5.

[0036] A threaded portion is formed on the inner surface of a recess formed in one end surface of the rod 66. A screw as a fixing member 65 is screwed to the threaded portion of the rod 66. It will be appreciated that by screwing the fixing member 65 to the rod 66, the vibration reducing member 61 is more firmly fixed, and as a result, the vibration suppression effect is further enhanced. The rod 66 may be an internally threaded screw, and the fixing member 65 may be an externally threaded screw, but the opposite is also possible.

[0037] A similar threaded recess may also be formed on the other end surface of the rod 66. In this case, another fixing member 65 is screwed to the rod 66 together with another vibration reducing member 61. This further enhances the vibration suppression effect. It will be understood that substantially the same effect is also obtained if the rod 66 is simply inserted into the three-phase reactor 5 at a position corresponding to the intersection point of the gaps 101 to 103. The rod 66 may be an internally threaded screw, and the fixing member 65 an externally threaded screw, but the opposite is also possible.

[0038] Fig. Figure 6A is a plan view of a vibration reduction element in an additional embodiment. Fig. The vibration-reducing member 61 shown in Figure 6A includes a leg portion 67a to 67c between two adjacent extension portions 61a to 61c. These leg portions 67a to 67c extend radially outward at the center position between two adjacent extension portions. It is assumed that the leg portions 67a to 67c are formed integrally with the vibration-reducing member 61.

[0039] Fig. Figure 6B is a plan view of a three-phase reactor on which the Fig. 6A was installed. To facilitate understanding, Fig. 6B, the representation of coils 51 to 53 is omitted. As in Fig. 6B, when the vibration suppression structure 60 is mounted, the extension portions 61a to 61c of the vibration reducing member 61 are engaged with the respective upper surfaces of the iron cores 41 to 43, and the leg portions 67a to 67c are inserted into the gaps 101 to 103, respectively.

[0040] In this case, the leg portions 67a to 67c are arranged between the iron cores 41 to 43. Consequently, even if the iron cores 41 to 43 are formed separately from the outer peripheral iron core 20, the iron cores 41 to 43 can be prevented from rotating and the iron cores 41 to 43 can be fixed more firmly.

[0041] It will be understood that as a result vibrations are suppressed even more.

[0042] Fig. Figure 6C is a disassembled oblique view of another choke coil in an additional embodiment. To facilitate understanding, Fig. 6C, the representation of the coils 51 to 53 has been omitted. From the tip ends of the leg sections 67a to 67c of the Fig. 6C, rod-shaped additional leg portions 68a to 68c extend perpendicular to the leg portions 67a to 67c.

[0043] The length of the leg portions 67a to 67c is slightly longer than the length (the distance in the radial direction) of the gaps 101 to 103.

[0044] When the vibration reducing member 61 is disposed at one end of the reactor 5, the additional leg portions 68a to 68c are in contact with the side surfaces of the iron cores 41 to 43. For this purpose, it is preferable that the cross section of the additional leg portions 68a to 68c be approximately Y-shaped. Then, the screw constituting the fixing member 65 is inserted into the hole 63, and the fixing member 65 is fixed to the other end of the reactor 5 by a nut 69. In this case, the additional leg portions 68a to 68c are held on the inside in the radial direction with respect to the iron cores 41 to 43. It will be understood that, therefore, in addition to the above-described effect, vibrations generated near the gaps 101 to 103 can be further suppressed.The use of nut 69 can also be omitted, in which case the effect is largely the same. The nut 69 can also be part of the fixing element 65.

[0045] Furthermore, Fig. 7A is a disassembled oblique view of a choke coil in yet another embodiment. Fig. 7B is an oblique view of the Fig. 7A. For convenience, Fig. 7A and Fig. 7B, a representation of the fixing element 65 etc. has been omitted. The additional leg sections 68a to 68c of the Fig. 7A are planar structures with a length range corresponding to the leg portions 67a to 67c. Therefore, the additional leg portions 68a to 68c are formed as shown in Fig. 7B, when the vibration reducing element 61 is arranged at one end of the choke coil 5. It will be understood that, therefore, vibrations generated in the vicinity of the gaps 101 to 103 are stronger than in the case of Fig. 6C can be suppressed.

[0046] Fig. 7C is a modification of the Fig. 4 shown embodiment. In Fig. 7C shows a vibration reducing element 61 which corresponds to the Fig. 7A. The length in the axial direction of the additional leg portions 68a to 68c is preferably at most half the length in the axial direction of the choke coil 5. It will be understood that in this case, too, the same effect as in the Fig. 4 shown embodiment.

[0047] Furthermore, Fig. 8 is a view showing a motor driving device incorporating the three-phase reactor of the present invention. Fig. 8, the three-phase reactor 5 is provided in a motor driving device.

[0048] It will be understood that in such a case, a motor drive device including the three-phase reactor 5 can be easily provided. The scope of the present invention also includes any combinations of some of the embodiments described above. Revelation of further exemplary forms

[0049] According to a first exemplary form, a three-phase reactor is provided which comprises an outer peripheral iron core surrounding the outer periphery and at least three iron core coils which are in contact with or connected to the inner surface of the outer peripheral iron core, wherein the at least three iron core coils are constructed from an iron core and a coil wound around this iron core, wherein a magnetically coupleable gap is formed between two mutually adjacent iron cores, and which is further provided with a vibration suppression structure which is arranged in the vicinity of the gaps and suppresses vibrations generated at the gaps.

[0050] According to a second exemplary form, the vibration suppression structure in the first exemplary form includes a vibration reducing member made of an elastic structure and a fixing member that fixes the vibration reducing member to the iron cores.

[0051] According to a third exemplary form, in the first or second exemplary form, the vibration suppression structure is arranged on at least one end surface of the three-phase reactor in the lamination direction of the iron cores.

[0052] According to a fourth exemplary form, the fixing element in one of the first to third exemplary forms is a screw or a combination of a screw and a nut.

[0053] According to a fifth exemplary form, the vibration reducing element in the second exemplary form comprises at least one leg portion which is inserted between two adjacent iron cores.

[0054] According to a sixth exemplary form, the vibration reducing element in the second exemplary form is formed from a non-magnetic body.

[0055] According to a seventh exemplary form, there is provided a motor driving device provided with the reactor of any one of the first to sixth exemplary forms. Results of the exemplary forms

[0056] In the first and second exemplary forms, the vibration suppression structure, which includes a vibration reduction element and a fixing element, is arranged only near the gap. Therefore, the three-phase reactor does not become large due to the vibration suppression structure, and the manufacturing costs are not significantly increased. Furthermore, the iron cores can be fixed regardless of the thickness of the iron cores of each phase.

[0057] In the third exemplary form, the effect of suppressing vibrations can be increased by a comparatively simple structure.

[0058] In the fourth exemplary form, the effect of suppressing vibrations can be increased by a comparatively simple structure.

[0059] In the fifth exemplary form, since the leg portions are arranged between the iron cores, the iron cores can be prevented from rotating and the iron cores can be fixed more firmly.

[0060] Since the magnetic permeability becomes low in the sixth exemplary form, magnetic saturation can be suppressed.

[0061] In the seventh exemplary form, the manufacturing cost and dimensions of a motor driving device can be avoided from increasing sharply.

Claims

[1] Three-phase reactor, the an outer peripheral iron core (20) surrounding the outer periphery, and at least three iron core coils (31 to 33) in contact with or connected to the inner surface of the outer peripheral iron core, wherein the at least three iron core coils comprise iron cores (41 to 43) and coils (51 to 53) wound around the iron cores, wherein a magnetically coupled gap (101 to 103) is formed between two adjacent iron cores, and which is further provided with a vibration suppression structure (60) arranged by a fixing element (65) at an intersection point of the gaps or in the vicinity of the intersection point of the gaps and suppresses vibrations arising at the gaps, wherein the fixing element (65) is arranged at least in sections in at least one of the gaps (101 to 103). [2] Three-phase reactor, the an outer circumference iron core (20) surrounding the outer circumference, and at least three iron core coils (31 to 33) which are in contact with or connected to the inner surface of the outer peripheral iron core, wherein the at least three iron core coils comprise iron cores (41 to 43) and coils (51 to 53) wound around the iron cores, wherein a magnetically coupled gap (101 to 103) is formed between two adjacent iron cores, and which is further provided with a vibration suppression structure (60) arranged by a fixing element (65) at an intersection point of the gaps or in the vicinity of the intersection point of the gaps and suppresses vibrations arising at the gaps, wherein the fixing element (65) is arranged at least in sections in at least one of the gaps (101 to 103), wherein the vibration suppression structure is arranged only at one end of the three-phase reactor in the layering direction of the iron cores. [3] Three-phase choke coil, the an outer peripheral iron core (20) surrounding the outer periphery, and at least three iron core coils (31 to 33) in contact with or connected to the inner surface of the outer peripheral iron core, wherein the at least three iron core coils comprise iron cores (41 to 43) and coils (51 to 53) wound around the iron cores, wherein a magnetically coupled gap (101 to 103) is formed between two adjacent iron cores, and which is further provided with a vibration suppression structure (60) which is arranged in the vicinity of the gaps and suppresses vibrations arising at the gaps, wherein the vibration suppression structure includes a vibration reducing element (61) having an elastic structure and a fixing element (65) for fixing the vibration reducing element to the iron cores, wherein the vibration reducing element includes at least three legs (67a to 67c), each of which is to be inserted between two adjacent iron cores. [4] A three-phase reactor according to claim 1 or 2, wherein the vibration suppression structure comprises a vibration reducing member (61) made of an elastic structure and the fixing member (65) fixing the vibration reducing member to the iron cores. [5] A three-phase reactor according to claim 1, 2 or 4, wherein the vibration suppression structure is arranged on at least one end surface of the three-phase reactor in the lamination direction of the iron cores. [6] A three-phase reactor according to claim 4, wherein the fixing member is a screw or a combination of a screw and a nut. [7] A three-phase reactor according to claim 4 or 5, wherein the vibration reducing member comprises at least one leg portion (67a to 67c) inserted between two adjacent iron cores. [8] A three-phase reactor according to claim 4, wherein the vibration reducing member is formed of a non-magnetic body. [9] A three-phase reactor according to claim 7, wherein the vibration reducing member (61) has additional leg portions (68a to 68c) extending perpendicularly at least partially with respect to the legs from the tips of the legs (67a to 67c) and coming into contact with the side surfaces of the iron cores. [10] A three-phase reactor according to claim 7, wherein the vibration reducing member (61) has additional leg portions (68a to 68c) extending perpendicularly at least partially with respect to the legs (67a to 67c) and inserted into the gaps (101 to 103), respectively. [11] A motor driving device provided with a three-phase reactor according to any one of claims 1 to 10.

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