JP2021144982A - Reactor with temperature detection unit - Google Patents

Abstract

To accurately detect coil temperature without the use of an additional component.SOLUTION: A reactor (6) includes an outer peripheral core (20) and at least three iron core coils (31 to 34). The iron core coils include respective iron cores (41 to 44) and coils (51 to 54). Recesses (71 to 74) are formed on the outer peripheral surface or the inner peripheral surface of at least one coil. A temperature detection unit (61 to 64) is arranged in the recesses.SELECTED DRAWING: Figure 1A

Description

The present invention relates to a reactor provided with a temperature detector.

In recent years, a reactor including a core body including an outer peripheral iron core and a plurality of iron cores arranged inside the outer peripheral iron core has been developed. A coil is attached to each of the plurality of iron cores. See, for example, Patent Document 1.

Further, Patent Document 2 discloses that the reactor includes a temperature detection unit arranged at the center of one end face of the core body.

JP-A-2017-139438 Japanese Unexamined Patent Publication No. 2019-004066

By the way, when an interlayer short circuit occurs in a coil of a certain phase of the reactor, a larger current flows than the coil of another phase. If this state continues, the temperature of the coil will rise more than expected, so the temperature of the coil will exceed the heat resistant temperature of the insulating member around the coil, the performance of the insulating member will deteriorate early, and a ground fault will occur. there's a possibility that. Therefore, it is required to detect the interlayer short circuit at an early stage by quickly detecting the temperature of the coil and protect the reactor before the insulating member around the coil is deteriorated by heat.

Normally, the coil and the iron core generate heat in the reactor, but when the power supply frequency is low, the rate of heat generation of the coil is large, and when the power supply frequency is high, the rate of heat generation of the iron core tends to be large. At commercial power frequencies of 50Hz and 60Hz, the rate of heat generation of the coil is high. Then, the temperature of the reactor tends to rise as the temperature of the coil rises. Therefore, it is important to monitor the temperature change of the coil especially when the power supply frequency is low. However, since the temperature detection unit of Patent Document 2 is provided at the center of the end face of the core body in the reactor, the temperature of the coil is not directly detected. In other words, in the case of Patent Document 2, even if the detected temperature of the end face of the core body is within the normal range, the temperature of the coil may be higher than the normal range, resulting in an interlayer short circuit. The possibility that it has occurred cannot be ruled out.

Therefore, it is preferable to arrange the temperature detection unit directly on the coil with an adhesive. However, from the time the temperature detection unit is placed on the coil until the adhesive solidifies, the temperature detection unit may be displaced, and the temperature detection unit may fall off from the coil. Therefore, it is necessary to fix the temperature detection unit to the coil with a fixing jig.

Further, when the coil mounted on the iron core is inserted into the coil case, the temperature detection unit can be arranged in the coil case. However, in this case, there arises a problem that the number of parts increases.

Therefore, there is a need for a reactor that can accurately detect the temperature of the coil without the use of additional components such as fixing jigs and coil cases.

According to the first aspect of the present disclosure, the outer peripheral iron core is provided with at least three iron core coils in contact with or coupled to the inner surface of the outer peripheral iron core, and the at least three iron cores are provided. Each of the coils is composed of an iron core and a coil mounted on the iron core, and the coil is composed of a wire rod wound a plurality of times, and the radial inner end of each of the at least three iron cores. The portions converge toward the center of the outer peripheral core, and a magnetically connectable gap between one of the at least three cores and the other core adjacent to the one core. Are formed, the radial inner ends of the at least three cores are separated from each other via a magnetically connectable gap, and at least one of the at least three coils. Provided is a reactor comprising a recess formed on the outer peripheral surface or the inner peripheral surface of the coil and a temperature detecting portion arranged in the recess.

In the first aspect, when the temperature detection unit is arranged in the recess formed on the outer peripheral surface of the coil, even if the adhesive between the coil and the temperature detection unit is not solidified. , The temperature detector does not fall out of the recess of the coil. Further, when the temperature detection unit is arranged with an adhesive in the recess formed on the inner peripheral surface of the coil, it is possible to prevent the temperature detection unit from being displaced during assembly of the reactor. Therefore, the fixing jig can be eliminated, and it is not necessary to use the coil case. Therefore, it is possible to accurately detect the temperature of the coil without using additional parts such as a fixing jig and a coil case.

The objects, features and advantages of the present invention will be further clarified by the following description of embodiments relating to the accompanying drawings.

It is a top view of the reactor based on this disclosure. It is a partial decomposition perspective view of the reactor shown in FIG. 1A. It is sectional drawing of the coil and the temperature detection part in 1st Embodiment. It is a perspective view of the reactor in the second embodiment. It is a partial decomposition perspective view of the coil and the temperature detection part shown in FIG. 3A. It is a partial decomposition perspective view of another coil and a temperature detection part. It is a partial perspective view of the coil and the temperature detection part shown in FIG. 3C. It is a perspective view of the reactor in the third embodiment. It is a partial decomposition perspective view of the coil and the temperature detection part shown in FIG. 4A. It is a partial decomposition perspective view of another coil and a temperature detection part. It is a partial side view of the coil shown in FIG. 4A. It is a perspective view of the reactor in 4th Embodiment. It is a partial decomposition perspective view of the coil and the temperature detection part shown in FIG. 5A. It is a partial decomposition perspective view of another coil and a temperature detection part. It is a side view of the reactor in the fifth embodiment. It is a partial decomposition perspective view of the coil and the temperature detection part shown in FIG. 6A. It is a top view of the reactor in another embodiment. It is a top view of the reactor in still another embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. A common reference code is attached to the corresponding components throughout the drawings.

In the following description, a three-phase reactor will be mainly described as an example, but the application of the present disclosure is not limited to the three-phase reactor, and can be widely applied to a multi-phase reactor that requires a constant inductance in each phase. be. Further, the reactor according to the present disclosure is not limited to those provided on the primary side and the secondary side of the inverter in an industrial robot or a machine tool, and can be applied to various devices.

FIG. 1A is a top view of the reactor based on the present disclosure. FIG. 1B is a partially decomposed perspective view of the reactor shown in FIG. 1A. As shown in FIGS. 1A and 1B, the core body 5 of the reactor 6 includes an outer peripheral iron core 20 and three core coils 31 to 33 arranged inside the outer peripheral iron core 20. In FIG. 1, the iron core coils 31 to 33 are arranged inside the outer peripheral iron core 20 having a substantially hexagonal shape. These iron core coils 31 to 33 are arranged at equal intervals in the circumferential direction of the core main body 5.

The outer peripheral iron core 20 may have another rotationally symmetric shape, for example, a circular shape. Further, the number of iron core coils may be a multiple of 3, and in that case, the reactor 6 can be used as a three-phase reactor.

As can be seen from the drawings, each iron core coil 31 to 33 includes an iron core 41 to 43 extending only in the radial direction of the outer peripheral iron core 20, and coils 51 to 53 mounted on the iron core. In other drawings, the coils 51 to 53 may be omitted for the sake of brevity.

The outer peripheral iron core 20 is composed of a plurality of, for example, three outer peripheral iron core portions 24 to 26 divided in the circumferential direction. The outer peripheral iron core portions 24 to 26 are integrally formed with the iron cores 41 to 43, respectively. The outer peripheral iron core portions 24 to 26 and the iron cores 41 to 43 are formed by laminating a plurality of magnetic plates, for example, an iron plate, a carbon steel plate, or an electromagnetic steel plate, or by forming a dust core. When the outer peripheral iron core 20 is composed of a plurality of outer peripheral iron core portions 24 to 26 in this way, even if the outer peripheral iron core 20 is large, such an outer peripheral iron core 20 can be easily manufactured. can. The number of iron cores 41 to 43 and the number of outer peripheral iron core portions 24 to 26 do not necessarily have to match.

Further, each of the radial inner ends of the iron cores 41 to 43 is located near the center of the outer peripheral iron core 20. In the drawing, the inner end portions of the iron cores 41 to 43 in the radial direction converge toward the center of the outer peripheral iron core 20, and the tip angle thereof is about 120 degrees. The radial inner ends of the iron cores 41 to 43 are separated from each other via magnetically connectable gaps 101 to 103.

In other words, the radial inner ends of the iron core 41 are separated from each other via gaps 101 and 103 from the respective radial inner ends of the two adjacent iron cores 42 and 43. The same applies to the other iron cores 42 and 43. The dimensions of the gaps 101 to 103 are assumed to be equal to each other.

As described above, in the configuration shown in FIG. 1A, since the central iron core located at the central portion of the core main body 5 is unnecessary, the core main body 5 can be constructed lightweight and easily. Further, since the three iron core coils 31 to 33 are surrounded by the outer peripheral iron core 20, the magnetic field generated from the coils 51 to 53 does not leak to the outside of the outer peripheral iron core 20. Further, since the gaps 101 to 103 can be provided with an arbitrary thickness at low cost, it is advantageous in design as compared with the reactor having the conventional structure.

Further, in the core body 5 of the present disclosure, the difference in magnetic path length between the phases is smaller than that of the reactor having the conventional structure. Therefore, in the present disclosure, it is also possible to reduce the imbalance of inductance caused by the difference in magnetic path length.

As can be seen with reference to FIGS. 1A and 1B, recesses 71 to 73 are formed on the outer peripheral surfaces of the coils 51 to 53, respectively. The temperature detection units 61 to 63 are arranged in each of the recesses 71 to 73. It is assumed that the temperature detection units 61 to 63 are connected to an external control device (not shown), for example, a CNC, a converter, an inverter, an I / O, or a computer by wire or wirelessly.

It is assumed that the temperature detection units 61 to 63 are arranged in the recesses 71 to 73 with the adhesive Z (see FIG. 2 and the like) applied to the recesses 71 to 73 of the coils 51 to 53 in advance. Next, such coils 51 to 53 are inserted into the iron cores 41 to 43 integrated with the outer peripheral iron core portions 24 to 26. Finally, the outer peripheral iron core portions 24 to 26 are assembled to each other, whereby the reactor 6 is formed.

In the present disclosure, the temperature detection units 61 to 63 are arranged in the recesses 71 to 73 formed on the outer peripheral surfaces of the coils 51 to 53. Therefore, even if the adhesive is not solidified when the outer peripheral iron core portions 24 to 26 are assembled, the temperature detection portions 61 to 63 do not fall off from the recesses 71 to 73. Therefore, in the present disclosure, the fixing jig of the prior art can be eliminated, and it is not necessary to use the coil case. Therefore, it is possible to accurately detect the temperature of the coils 51-53 without the use of additional parts such as fixing jigs and coil cases.

For this purpose, the recesses 71 to 73 are preferably formed on the outer peripheral surfaces of the coils 51 to 53 on the upper end side of the reactor 6 in the axial direction. However, the recesses 71 to 73 may be formed in other portions of the outer peripheral surface of the coils 51 to 53. Further, the recesses 71 to 73 have a depth that at least partially receives the temperature detection units 61 to 63. The depth of the recesses 71 to 73 is preferably equal to or greater than the thickness of the temperature detection portions 61 to 63.

When the reactor 6 is driven, the temperature detection units 61 to 63 detect the temperature of the coils 51 to 53 in a predetermined cycle. Then, when the temperature of at least one of the coils 51 to 53 is higher than a predetermined value, the reactor 6 is stopped by an external control device (not shown). As a result, the reactor 6 can be protected before it is deteriorated by heat.

FIG. 2 is a cross-sectional view of the coil and the temperature detection unit in the first embodiment. In FIG. 2 and other drawings described later, only the coil 51, the temperature detection unit 61, and the recess 71 are shown, but the same applies to the other coils 52, 53, the other temperature detection units 62, 63, and the other recesses 72, 73. Suppose that

The coil 51 shown in FIG. 2 is formed by winding a conductive wire rod having a circular cross section a plurality of times. In FIG. 2, the coils 51 include three coil regions C1 to C3 that are adjacent to each other. The coil region C3 is located between the coil regions C1 and C2.

In FIG. 2, the number of turns in the coil region C1 located on the outer peripheral surface side of the reactor 6 and the coil region C2 located on the center side of the reactor 6 is 3, and the number of turns in the coil region C3 located between them is 2. Is. That is, the number of turns in the coil regions C1 and C2 is larger than the number of turns in the coil region C3.

As described above, in the first embodiment, the recess 71 is formed by changing the number of turns or the number of stages between the coil regions C1 and C3 and the coil regions C2 and C3 adjacent to each other. Further, in FIG. 2, with respect to the coil regions C1 and C2, the number of wire rod portions in the radial direction of the reactor 6 is one, but may be plural. The wire rod portion is a portion of the same wire rod that is different from each other.

In FIG. 2, the temperature detection units 61 to 63 do not fall off from the recesses 71 to 73 even when the adhesive is not solidified when the outer peripheral iron core portions 24 to 26 are assembled, and the temperature detection units 61 to 63 do not fall off from the recesses 71 to 73. It is possible to prevent the temperature detection units 61 to 63 from being displaced in the radial direction of the reactor 6. The cross section of the wire may have a shape other than a circle.

FIG. 3A is a perspective view of the reactor in the second embodiment, FIG. 3B is a partially exploded perspective view of the coil and the temperature detection unit shown in FIG. 3A, and FIG. 3C is a partial decomposition of the other coil and the temperature detection unit. It is a perspective view, and FIG. 3D is a partial perspective view of the coil and the temperature detection unit shown in FIG. 3C.

The coil 51 shown in FIGS. 3A and 3B is formed by winding a conductive wire rod having a circular cross section a plurality of times. As shown in FIG. 3D, the wire rod portion of the coil region C4 located on the outermost side of the coil 51 is partially bent, whereby the recess 71 is formed.

Further, the coil 51 shown in FIG. 3C is a single conductive wire having a rectangular cross section, that is, a flat wire coil formed by winding a flat wire a plurality of times. Such a coil 51 may be bent to form a recess 71 in the same manner.

In the second embodiment, the temperature detection units 61 to 63 do not fall off from the recesses 71 to 73 even when the adhesive is not solidified when the outer peripheral iron core portions 24 to 26 are assembled. Further, it is possible to prevent the temperature detection units 61 to 63 from being displaced in the circumferential direction of the reactor 6. Further, in the second embodiment, there is an effect that the recess 71 suitable for the temperature detection unit 61 having various shapes can be easily created.

4A is a perspective view of the reactor according to the third embodiment, FIG. 4B is a partially disassembled perspective view of the coil and the temperature detection unit shown in FIG. 4A, and FIG. 4C is a partially disassembled view of the other coil and the temperature detection unit. It is a perspective view, and FIG. 4D is a partial side view of the coil shown in FIG. 4A.

The coil 51 in FIGS. 4A, 4B and 4D is a flat wire coil. In FIG. 4D, the coils 51 include three coil regions C5 to C7 that are adjacent to each other. The coil region C6 is located on the outer peripheral surface side of the reactor 6, and the coil region C7 is located on the center side of the reactor. The coil region C5 is located between the coil regions C6 and C7.

In FIG. 4D, the position of the wire rod portion in the coil regions C6 and C7 is higher in the axial direction of the reactor 6 than the position of the wire rod portion in the coil region C5 located between them. That is, the wire rod portion in the coil regions C6 and C7 and the wire rod portion in the coil region C5 are displaced from each other in the axial direction of the reactor 6. As a result, the recess 71 is formed between the coil regions C6 and C7. As a result, the recess 71 can be easily formed even when a flat wire coil is used.

Therefore, even if the adhesive is not solidified when the outer peripheral iron core portions 24 to 26 are assembled, the temperature detection units 61 to 63 do not fall off from the recesses 71 to 73, and the temperature detection unit It is possible to prevent 61 to 63 from being displaced in the radial direction of the reactor 6.

Further, as shown in FIG. 4C, the coil 51 may be formed by winding a conductive wire rod having a circular cross section a plurality of times. Also in this case, the recess 71 can be formed in the same manner as described above, and therefore the same effect can be obtained.

FIG. 5A is a perspective view of the reactor according to the fourth embodiment, FIG. 5B is a partial decomposition perspective view of the coil and the temperature detection unit shown in FIG. 5A, and FIG. 5C is a partial decomposition of the other coil and the temperature detection unit. It is a perspective view.

The coil 51 in FIGS. 5A and 5B is a flat wire coil. In the recesses 71 to 73 in the fourth embodiment, as described with reference to FIG. 3D, the wire rod portion of the coil region located on the outermost side of the coil 51 is partially bent, and FIG. 4D is referred to. As described above, the coils are formed by shifting the positions of adjacent coil regions from each other.

As can be seen from FIG. 5B, the temperature detecting portion 61 to be inserted into the recess 71 is surrounded by a part of the coil 51 in both the radial direction and the circumferential direction of the reactor 6. Therefore, even if the adhesive is not solidified when the outer peripheral iron core portions 24 to 26 are assembled, the temperature detection units 61 to 63 do not fall off from the recesses 71 to 73, and the temperature detection unit It is possible to prevent 61 to 63 from being displaced in the radial and circumferential directions of the reactor 6. Therefore, the temperature of the coil 51 can be detected more accurately.

FIG. 6A is a side view of the reactor according to the fifth embodiment, and FIG. 6B is a partially decomposed perspective view of the coil and the temperature detection unit shown in FIG. 6A. The coils 51 to 53 in these drawings are flat wire coils. The temperature detection units 61 to 63 are arranged in recesses 71 to 73 formed on the inner peripheral surfaces of the coils 51 to 53. The recesses 71 to 73 in these drawings are formed by bending the wire rods of the coils 51 to 53. Alternatively, the recesses 71 to 73 may be formed on the inner peripheral surface of the coils 51 to 53 by some of the other methods described above. Further, the coils 51 to 53 may be formed by winding a conductive wire rod having a circular cross section a plurality of times.

Since the temperature detection units 61 to 63 are arranged in the recesses 71 to 73 with an adhesive, even if the temperature detection units 61 to 63 come into contact with other members when assembling the outer peripheral iron core portions 24 to 26, the temperature The detection units 61 to 63 do not shift in the radial direction and / or the circumferential direction of the reactor 6. Therefore, the fixing jig of the prior art can be eliminated, and it is not necessary to use the coil case. Therefore, it is possible to accurately detect the temperature of the coils 51-53 without the use of additional parts such as fixing jigs and coil cases.

FIG. 7 is a top view of the reactor in another embodiment. The core body 5 shown in FIG. 7 includes a substantially octagonal outer peripheral iron core 20 and four core coils 31 to 34 similar to those described above, which are arranged inside the outer peripheral iron core 20. .. These iron core coils 31 to 34 are arranged at equal intervals in the circumferential direction of the core main body 5. Further, the number of iron cores is preferably an even number of 4 or more, so that a reactor provided with a core body 5 can be used as a single-phase reactor.

As can be seen from the drawing, the outer peripheral iron core 20 is composed of four outer peripheral iron core portions 24 to 27 divided in the circumferential direction. Each of the iron core coils 31 to 34 includes an iron core 41 to 44 extending in the radial direction and coils 51 to 54 mounted on the iron core. The radial outer ends of the iron cores 41 to 44 are integrally formed with the outer peripheral iron core portions 24 to 27, respectively. The number of iron cores 41 to 44 and the number of outer peripheral iron core portions 24 to 27 do not necessarily have to match.

Further, each radial inner end of the iron cores 41 to 44 is located near the center of the outer peripheral iron core 20. In FIG. 7, each radial inner end of the iron cores 41 to 44 converges toward the center of the outer peripheral iron core 20, and the tip angle thereof is about 90 degrees. The radial inner ends of the iron cores 41 to 44 are separated from each other via magnetically connectable gaps 101 to 104.

In FIG. 7, similarly to FIGS. 1A and the like, recesses 71 to 74 are formed on the outer peripheral surfaces of the coils 51 to 54, and temperature detection units 61 to 64 are inserted into the recesses 71 to 74, respectively. Therefore, it can be seen that the same effect as described above can be obtained.

FIG. 8 is a top view of the reactor in yet another embodiment, similar to FIG. 1A. In FIG. 8, the recess 71 is formed only on the outer peripheral surface of the coil 51, and the recesses 72 and 73 are not formed in the other coils 52 and 53. The recess 71 may be formed on the inner peripheral surface of the coil 51. In this case, only a single temperature detection unit 61 is arranged in the recess 71. Again, it will be apparent that it falls within the scope of this disclosure.

Aspects of the present disclosure According to the first aspect, the outer peripheral iron core (20) and at least three core coils (31 to 34) in contact with or coupled to the inner surface of the outer peripheral iron core. Each of the at least three iron core coils is composed of an iron core (41 to 44) and a coil (51 to 54) mounted on the iron core, and the coil is wound a plurality of times. It is composed of a wire rod, and the radial inner ends of each of the at least three cores converge toward the center of the outer peripheral core, and one of the at least three cores and one of the cores. A magnetically connectable gap is formed between the iron core and other iron cores adjacent to the iron core, and the radial inner ends of the at least three iron cores are magnetically connectable gaps (101 to 104). ), And further, recesses (71 to 74) formed on the outer peripheral surface or inner peripheral surface of at least one of the at least three coils, and the temperature arranged in the recesses. A reactor (6) comprising a detection unit (61-64) is provided.
According to the second aspect, in the first aspect, the recess is formed by changing the number of turns of the wire rod in the coil region adjacent to each other of the coil.
According to the third aspect, in the first aspect, the recess is formed by bending a part of the wire rod of the coil.
According to the fourth aspect, in the first or third aspect, the recessing positions the winding position of the wire rod portion of the wire rod portion in the coil region adjacent to each other of the coil in the axial direction of the reactor. It is formed by shifting.
According to the fifth aspect, in any one of the first to fourth aspects, the number of the at least three core coils is a multiple of three.
According to the sixth aspect, in any one of the first to fourth aspects, the number of the at least three core coils is an even number of 4 or more.

Effect of Aspect In the first aspect, when the temperature detection part is arranged in the recess formed on the outer peripheral surface of the coil, the adhesive between the coil and the temperature detection part is not solidified. Even if there is, the temperature detection unit does not fall out from the recess of the coil. Further, when the temperature detection unit is arranged with an adhesive in the recess formed on the inner peripheral surface of the coil, it is possible to prevent the temperature detection unit from being displaced during assembly of the reactor. Therefore, the fixing jig can be eliminated, and it is not necessary to use the coil case. Therefore, it is possible to accurately detect the temperature of the coil without using additional parts such as a fixing jig and a coil case.
In the second aspect, it is possible to prevent the temperature detection unit from being displaced in the radial direction of the reactor.
In the third aspect, it is possible to prevent the temperature detection unit from being displaced in the circumferential direction of the reactor.
In the fourth aspect, it is possible to prevent the temperature detection unit from being displaced in the radial direction of the reactor.
In the fifth aspect, the reactor can be used as a three-phase reactor.
In the sixth aspect, the reactor can be used as a single-phase reactor.

Although the embodiments of the present invention have been described above, it will be understood by those skilled in the art that various modifications and changes can be made without departing from the disclosure scope of the claims described later.

5 Core body 6 Reactor 20 Outer peripheral iron core 24-27 Outer peripheral iron core part 31-34 Iron core coil 41-44 Iron core 51-54 Coil 61-64 Temperature detector 71-74 Recess 101-104 Gap C1-C7 Coil area

Claims (6)

Peripheral iron core and
It comprises at least three iron core coils that are in contact with or coupled to the inner surface of the outer peripheral iron core.
Each of the at least three core coils is composed of an iron core and a coil mounted on the iron core.
The coil is composed of a wire rod wound a plurality of times.
The radial inner ends of each of the at least three cores converge toward the center of the outer peripheral core.
A magnetically connectable gap is formed between one of the at least three cores and the other core adjacent to the one core, and the radial inside of the at least three cores. The ends are separated from each other through a magnetically connectable gap.
Moreover,
A recess formed on the outer peripheral surface or the inner peripheral surface of at least one of the at least three coils,
A reactor comprising a temperature detection unit arranged in the recess. The reactor according to claim 1, wherein the recess is formed by changing the number of turns of the wire rod in a coil region adjacent to each other of the coil. The reactor according to claim 1, wherein the recess is formed by bending a part of the wire rod of the coil. The reactor according to claim 1 or 3, wherein the recess is formed by shifting the winding position of the wire rod portion of the wire rod portion of the wire rod portion in a coil region adjacent to each other of the coil in the axial direction of the reactor. .. The reactor according to any one of claims 1 to 4, wherein the number of the at least three core coils is a multiple of 3. The reactor according to any one of claims 1 to 4, wherein the number of the at least three core coils is an even number of 4 or more.

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