TW201742084A - Transformer - Google Patents

Abstract

In order to achieve a transformer (1) having a low loss, the transformer (1) is provided with: iron cores (3); coils (6, 7) wound on the iron cores; a first frame body (9) that suppresses deformation of the coils (6, 7), while supporting the weight of the iron cores (3), said deformation being in the axis direction; eddy current suppressing sections (24), which are provided at a plurality of areas of the first frame body (9), and which suppress an eddy current flowing in the first frame body (9); and a second frame body (10), which is insulated from the first frame body (9), and which suppresses deformation of the coils (6, 7), said deformation being in the direction orthogonal to the axis direction.

Description

transformer

The invention relates to a transformer.

In the transformer, particularly in large products, in order to prevent damage to the core or the coil, various support members are provided. For example, in the abstract of the following Patent Document 1, the first upper core supporting portion provided on the first end face side in the stacking direction of the thin strip of the magnetic material, which is provided on the upper portion of the core, and the above-described The second upper core support portion on the second end face side on the opposite side of the first end face side supports the upper portion of the iron core, and the first upper core support portion and the second upper core support portion are the same as the iron core The metal strip has a shape in which the width direction of the magnetic material extends in a direction perpendicular to the longitudinal direction, and the core is disposed therebetween, and the first upper core supporting portion and the second upper core supporting portion are close to each other. The protruding portion is provided with a protruding portion, and a bridging member provided on the protruding portion of the first upper core supporting portion and the protruding portion of the second upper core supporting portion is provided, and the bridge member supports the iron core. .

Further, in the abstract of the following Patent Document 2, "at least one coil 2 is described, and the plural is placed on the width of the core of the coil. The coil bobbin 23 formed of the bobbin members 23a and 23b‧‧ is provided on the innermost circumference of the coil 2. Further, the outermost amorphous core 1A encloses the core 1A and has a reinforcing frame that presses the outer side of the coil 2 into which the core 1A is inserted.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2013-8808

[Patent Document 2] Japanese Patent Laid-Open No. Hei 10-340815

Regarding the support members disclosed in Patent Documents 1 and 2, metals such as steel skeletons are mainly applied. However, when the metal is applied to the supporting member, the leakage flux from the core generates an eddy current in the supporting member, causing a problem that the loss is increased.

This invention has been made in view of the above circumstances, and an object thereof is to provide a transformer with low loss.

In order to solve the above problems, the transformer of the present invention includes: a core; a coil wound around the core; and a first frame that supports the weight of the core and suppresses deformation of the coil in the axial direction; and In the plural of the first frame, the flow is suppressed in the foregoing 1 eddy current eddy current suppression unit of the frame.

According to the present invention, a transformer with low loss can be realized.

1, 2‧‧‧ transformer

3‧‧‧Volume core (iron core)

6‧‧‧One coil (coil)

7‧‧‧second coil (coil)

9, 29‧‧‧ outer frame (first frame)

10, 30‧‧‧ inner frame (second frame)

11‧‧‧core support plate

12‧‧‧Upper beam (long strip conductor)

13‧‧‧Lower beam (long strip conductor)

14‧‧‧ Columns (long strip conductors)

15‧‧‧foot

16‧‧‧Coil lock bolt (pressure adjustment unit)

17‧‧‧Connected components

18‧‧‧Outer board

18a‧‧‧Insulation board

19‧‧‧ Column Department

20‧‧‧core protection frame

20a‧‧‧ inner board

24‧‧‧Construction parts (eddy current suppression unit)

25‧‧‧ bolt

26‧‧‧ screw holes

27‧‧‧Slit (eddy current suppression unit)

A1~A3‧‧‧ intersection

Φ _S ‧‧‧ leakage flux

I _S ‧‧‧ eddy current

Fig. 1 is a perspective view of a single-phase three-legged transformer according to a first embodiment of the present invention.

Fig. 2 is a (a) cross-sectional view and (b) a longitudinal cross-sectional view of the coil.

FIG. 3 is a perspective view of the outer frame body.

Fig. 4 is a perspective view of the inner frame body.

Fig. 5 is an explanatory diagram of leakage flux and eddy current of the transformer.

FIG. 6 is an enlarged view of an important part of FIG. 5. FIG.

Fig. 7 is a perspective view of a single-phase three-legged transformer according to a second embodiment of the present invention.

[First embodiment]

Fig. 1 is a perspective view of a single-phase three-legged transformer 1 according to a first embodiment of the present invention. The transformer 1 has two coil cores 3 (cores) having a rectangular ring shape; a primary coil 6 wound around the wound core 3; and a secondary coil 7 (coil) wound around the outer circumference of the primary coil 6 (coil); Outer frame 9 (first frame); and inner frame 10 (second frame). Here, the wound core 3 is formed by laminating and winding an amorphous magnetic ribbon on the one hand, and forming a ring shape. Compared with the electromagnetic steel sheet, the amorphous magnetic ribbon is thin and brittle, and generally, the wound core 3 using the amorphous magnetic ribbon is easily broken by the weight of the core or the electromagnetic force.

Here, in FIGS. 2(a) and 2(b), a cross-sectional view and a longitudinal cross-sectional view of the coils 6, 7 are shown.

In Figs. 2(a) and 2(b), the primary coil 6 and the secondary coil 7 are formed into a tubular shape. Here, an arrow drawn with a hatching indicates the direction of the electromagnetic force that operates when current flows in the coils 6, 7. That is, as shown in Fig. 2(a), the coils 6, 7 operate with electromagnetic forces that expand in the horizontal direction (direction orthogonal to the axial directions of the coils 6, 7). Further, as shown in Fig. 2(b), the coils 6, 7 also operate electromagnetic forces that expand in the axial direction, that is, the axial directions of the coils 6, 7. In proportion to the current flowing in the coils 6, 7, the electromagnetic force becomes large. In particular, if the transformer 1 is a large one and the secondary coil 7 is short-circuited, the electromagnetic force generated is also about several hundred tons.

Referring back to Fig. 1, the frames 9 and 10 are provided to suppress deformation of the coils 6, 7 in the case where the secondary coil 7 is short-circuited. First, the inner frame body 10 is formed to surround the winding core 3 from the right and left up and down directions, and mainly serves to suppress expansion of the coils 6 and 7 in the left-right direction. Further, the outer frame body 9 is formed to surround the inner frame body 10 from the front, rear, left, and right directions, and supports the core 3 and the coils 6, 7 and suppresses the expansion of the coils 6 and 7 in the vertical direction. Further, the outer frame body 9 suppresses the expansion of the inner frame body 10 in the left-right direction by abutting against the left and right side surfaces of the inner frame body 10, thereby The casing 10 suppresses the expansion of the coils 6, 7 in the left-right direction. The main parts of the frames 9 and 10 are preferably metal materials such as stainless steel or steel from the viewpoint of strength and cost. Further, the frames 9 and 10 are electrically insulated (described later in detail).

Next, FIG. 3 is a perspective view of the outer frame 9. In Fig. 3, the outer frame body 9 is formed in a substantially rectangular parallelepiped frame shape, and has four columnar portions 14 of H steel which are erected along the vertical sides of the rectangular parallelepiped. The four lower beam portions 13 (long strip-shaped conductor members) are formed into a rectangular tubular shape. The lower end portion of the column portion 14 (long conductor material) adjacent to the front, rear, left, and right directions is connected. Further, the four upper beam portions 12 (long strip-shaped conductor members) are formed into a rectangular tubular shape, and are connected to the upper end portions of the column portions 14 adjacent to the front, rear, left, and right directions. Further, from the intersection of the four portions of the column portion 14 and the lower beam portion 13, the leg portion 15 of the H steel protrudes to the lower direction. On the upper surface of the upper beam portion 12, covering the front-rear direction, the bridge has two core support plates 11 formed in a rectangular plate shape.

The core supporting plate 11 supports the upper side portions of the two winding cores 3 (see FIG. 1) from the inner side (lower side). Accordingly, the weight of the core 3 is not directly applied to the coils 6, 7. Further, in the upper beam portion 12, a coil lock bolt 16 (pressure adjustment portion) is attached to a portion surrounded by the two core support plates 11. The coil lock bolts 16 suppress the expansion of the coils 6 and 7 in the vertical direction when the secondary coils 7 are short-circuited or the like by pressing the coils 6 and 7 (see FIG. 1) in the downward direction. Here, the coil locking bolt 16 is rotated in the specified direction, and the pressure on the coils 6, 7 is increased. Therefore, the optimum pressing force can be applied to the coils 6, 7 by applying the coil locking bolts 16.

Next, FIG. 4 is a perspective view of the inner casing 10. In Fig. 4, the inner frame body 10 is formed in a substantially rectangular parallelepiped frame shape, and has two outer plates 18 which are erected along the left and right side faces of the rectangular parallelepiped to form a rectangular plate shape. The inner surface of the outer panel 18 is fixed to a plurality of column portions (in the illustrated example, 2 × 4). In the outer surface of the outer panel 18, an insulating plate 18a is attached to a portion that contacts the outer casing 9 (see FIG. 3), thereby insulating the inner casing 10 and the outer casing 9.

The core protection frame 20 is attached to the inner side of each of the column portions 19, and is formed integrally with the outer plate 18 and the column portion 19 to form a plurality of cylindrical bodies (in the illustrated example, 2 × 3) having a substantially rectangular cross section. In these cylinders, the legs of the core 3 (see Fig. 1) can be loosely inserted. However, in order to prevent a current loop in the horizontal direction from occurring in the core protection casing 20, an insulating plate (not shown) is interposed between the core protection casing 20 and the column portion 19. Further, a plurality of (2 × 3 in the illustrated example) connecting members 17 are fixed to the upper end portion and the lower end portion of the two outer sheets 18. Next, the two winding cores 3 are arranged in a rectangular region surrounded by the connecting member 17 and the column portion 19.

Further, the inner panel 20a of the core protection frame 20 is abutted against the secondary coil 7 (see Fig. 1). Therefore, when the secondary coil 7 is expanded in the left-right direction due to a short circuit or the like of the secondary coil 7, the expansion of the secondary coil 7 can be suppressed by the inner plate 20a. As described above, the leg portion of the winding core 3 is loosely inserted by the cylindrical body having a substantially rectangular cross section formed by the outer panel 18, the column portion 19, and the core protecting frame 20.

Here, the inner panel 20a of the core protection housing 20 and the leg portions of the winding core 3 are arranged to form a gap therebetween. Through this, When the secondary coil 7 is inflated and the inner panel 20a is deformed, collision of the inner panel 20a with the wound core 3 can be prevented. In other words, by providing a gap between the inner panel 20a and the core 3, it is possible to prevent the electromagnetic force applied to the secondary coil 7 from being applied to the wound core 3, and the breakage of the wound core 3 can be prevented.

Next, FIG. 5 is an explanatory diagram of leakage magnetic flux and eddy current of the transformer 1. When a current flows in the coils 6, 7, a magnetic flux flows in the wound core 3. However, a part of the generated magnetic flux flows as the leakage magnetic flux Φ _S shown in the figure, and flows outside the winding core 3. The leakage flux Φ _{S is} interlinked with the outer frame 9. It is assumed that if the entire outer frame 9 is made of a conductor, as shown in the figure, an eddy current flows in the direction of eliminating the leakage flux Φ _S . I _S , the loss of transformer 1 increases.

In the present embodiment, the outer frame body 9 is configured to block the eddy current I _S , and the details thereof will be described below. First, the outer frame body 9 is formed in a slightly rectangular parallelepiped shape. In the upper beam portion 12, the lower beam portion 13, the column portion 14, and the leg portion 15, a total of "8" intersections are generated corresponding to the respective vertices of the rectangular parallelepiped. Among these "8" intersections, at the intersection of "3" (for example, the intersections A1 to A3 shown in the figure), the respective portions 12, 13, 14, 15 are insulated from each other.

Further, the intersections A1 to A3 shown in the figure are one example. Generally, the intersections A1 to A3 are selected as follows. First, the intersection A1 can be arbitrarily selected from the intersection of eight. Next, the intersection A2 is where the position is at the intersection with the intersection A1. Next, the intersection A3 can be arbitrarily selected from the intersections other than the intersections A1 and A2. When the intersections A1 to A3 are selected as described above, the closed circuit is not formed in the outer casing 9, and the eddy current I _S does not flow.

Next, Fig. 6 is an enlarged view of the intersection A3 in Fig. 5. The structural member 24 (eddy current suppressing portion) has a shape in which a plurality of rectangular frame-shaped protruding openings are formed in a block-like body having a substantially cubic insulator. Next, a pair of lower beam portions 13, column portions 14, and leg portions 15 are individually inserted into these protruding openings. Further, the structural member 24 is configured such that the respective portions 13, 14, 15 are not in contact with each other. Further, a plurality of screw holes 26 are formed in the protruding opening of the structural member 24, and the respective portions 13, 14, 15 are fixed to the structural member 24 via the screwing of the bolts 25. Thus, the structural members 24 are insulated from each other and the portions 13, 14, 15 are joined.

From the viewpoint of strength, it is desirable to use FRP (Fiber Reinforced Plastics), a phenol resin, a press plate, a reinforced wood, a ceramic, etc., and it is desirable to use a material having a specific resistance of 1 × 10 ¹² Ω ‧ cm or more. Further, it is preferable that the bolt 25 is an insulating bolt. By using the insulating bolt, it is possible to reduce the possibility that the joint portion of the structural member 24 and the respective portions 12, 13, 14, 15 is broken due to the electromagnetic force when the secondary coil 7 is short-circuited. In the case where the widths of the respective portions 12, 13, 14, and 15 are the same, the same structural member 24 can be applied to the plurality of intersections A1 to A3 (see FIG. 5).

Further, also in the inner casing 10 shown in Fig. 4, a configuration for preventing eddy currents can be applied. For example, in the case where the outer panel 18 is made of metal, the connecting member 17 can be constituted by an insulator. In this case, as the insulator used in the connecting member 17, it is desirable to use FRP, a phenol resin, a press plate, a reinforced wood, a ceramic, etc. from the viewpoint of strength, and it is desirable to use a resistivity of 1 × 10 ¹² Ω ‧ cm The above materials.

As described above, the transformer (1) of the present embodiment has a first housing (9) that suppresses the deformation of the core (3) in the axial direction while supporting the weight of the core (3); The eddy current suppressing portion (24) that suppresses the eddy current flowing in the first casing (9) is provided at a plurality of points of the first casing (9). Accordingly, on the one hand, the breakage of the coils (6, 7) is prevented, and on the one hand, the eddy current loss is reduced, and the loss can be reduced.

Further, the transformer (1) further includes a second casing (10) that insulates the first casing (9) and suppresses deformation of the coils (6, 7) in a direction orthogonal to the axial direction. Thereby, the deformation of the coils (6, 7) can be further suppressed.

Further, the first frame body (9) includes a plurality of elongated conductor materials (12, 13, 14) disposed along each side of the rectangular parallelepiped; and the eddy current suppressing portion (24) is provided in a rectangular parallelepiped One of the plurality of vertices is the first insulating member of the first vertex (A1), the second insulating member provided at the second vertex (A2) of the diagonal of the first vertex, and the first insulating member. The vertex of one of the second vertex and the third vertex is the third insulating member of the third vertex (A3). Accordingly, the eddy current can be effectively suppressed by a small number of insulating members as much as possible.

Further, the first frame body (9) is provided with the pressing force adjusting portion (16) for adjusting the pressing force of the coils (6, 7), and the optimum pressing force can be applied to the coils (6, 7).

[Second embodiment]

Fig. 7 is a perspective view of a single-phase three-legged transformer 2 according to a second embodiment of the present invention. In addition, in FIG. 7, the same code|symbol is attached|subjected in the part corresponding to each of FIG.

The transformer 2 includes two coil cores 3 having a rectangular ring shape, a primary coil 6 wound around the wound core 3, a secondary coil 7 wound around the outer circumference of the primary coil 6, and an outer casing 29 (first casing) ); and the inner frame 30 (second frame). Here, the configuration of the winding core 3 and the coils 6 and 7 is the same as that of the first embodiment. The overall shape of the outer frame body 29 and the inner frame body 30 is the same as that of the outer frame body 9 and the inner frame body 10 of the first embodiment. However, the frame bodies 29 and 30 in the present embodiment do not have the structure member 24 (see FIG. 6) in the first embodiment, and are almost entirely composed of metal.

In the present embodiment, in order to suppress the eddy current I _S (see FIG. 5 ), a groove-shaped recessed portion, that is, a slit 27 (eddy current suppressing portion) is formed in the frames 29 and 30. In other words, the portion in which the slits 27 are formed in the frames 29 and 30 is the "eddy current suppressing portion" in the present embodiment. The slit 27 is formed to be orthogonal to the direction in which the eddy current I _S flows in order to form an impedance value by the skin effect. Further, the depth of the slit 27 is preferably determined in consideration of the effect of reducing the eddy current I _S and the mechanical strength of the frames 29 and 30. For example, in the case where the power supply frequency is 50 to 60 Hz, the depth is ideally in the range of 1 mm to 10 mm. As described above, even if the insulators are not used for the frames 29 and 30, the eddy current I _S can be suppressed.

[Modification]

The present invention is not limited to the above embodiments, and various modifications are possible. The above-described embodiments are illustrative for ease of understanding of the present invention, and are not intended to limit the configuration. Further, a part of the configuration of one embodiment may be replaced with another configuration, and a configuration of another embodiment may be added to the configuration of another embodiment. Further, it is possible to delete a part of the configuration of each embodiment or to add or replace another configuration. The modifications that can be made to the above embodiment are, for example, the following.

‧ The transformers 1 and 2 of the above-described embodiments have both the outer frames 9 and 29 and the inner frames 10 and 30. However, when the secondary coil 7 is short-circuited, the electromagnetic force in the left-right direction is not so large. The inner frames 10 and 30 may be omitted. In this case, the outer frames 9 and 29 can be configured to abut against the core 3 from the left-right direction and suppress deformation of the core 3 .

In the first embodiment described above, the structural member 24 and the respective portions 13, 14, 15 are joined by the bolts 25 and the screw holes 26, and instead of the structural members 24 and the respective portions 13, 14, 15 by the adhesive. Components.

In the first embodiment, the eddy current flowing through the inner casing 10 is suppressed by forming the outer panel 18 from a metal and forming the connecting member 17 by an insulator. However, the outer panel 18 and the connecting member 17 may be formed of a metal piece and the insulator may be combined to bond the two.

‧ In addition, in the outer frame body 9 of the first embodiment described above, Among the vertices at the eight corners of the rectangular parallelepiped, the intersections A1 to A3 corresponding to the vertices at three places are applied to the insulating structural member 24; however, the structural member 24 may be applied at the intersection of four or more places, or The structural member 24 is applied to the intersection of all eight places.

‧ In addition, in the first embodiment described above, in order to completely eliminate the influence of the eddy current, all the frames 9 and 10 may be formed of an insulator. In this case, all of the frames 9 and 10 are "eddy current suppressing portions". At this time, the load of the core 3 can be supported, and a material having high mechanical strength can be used for the frames 9 and 10 so as not to be broken by the electromagnetic force generated when the coil 2 is short-circuited. Specifically, in the frames 9 and 10, it is desirable to use FRP (Fiber Reinforced Plastics), a phenol resin, a press plate, a reinforced wood, a ceramic, etc., and it is desirable to use a material having a specific resistance of 1 × 10 ¹² Ω ‧ cm or more.

‧ In the above embodiments, the single-phase three-legged transformers 1 and 2 are described as an example. However, the present invention is not limited to the type of the transformer, and the present invention is also applicable to a three-phase five-pin transformer or a three-phase three-legged. Transformer, etc. When the type of the transformer is changed, the number of coils or the number of cores of the coil core may be different. However, in order to prevent the outer casing and the inner casing from forming a closed circuit, it is possible to suppress the flow in the frame by electrically insulating at an appropriate position. The eddy current of the body reduces the load loss.

1‧‧‧Transformer

3‧‧‧Volume core (iron core)

6‧‧‧One coil (coil)

7‧‧‧second coil (coil)

9‧‧‧Outer frame (1st frame)

10‧‧‧Inner frame (2nd frame)

Claims (7)

A transformer comprising: a core; a coil wound around the core; and a first frame that supports the weight of the core on the one hand, and suppresses deformation of the coil in the axial direction on the one hand; and an eddy current suppression unit; The plurality of first housings are provided at the plurality of positions, and the eddy current flowing in the first housing is suppressed. The transformer of claim 1, further comprising: a second housing that insulates the first housing from deformation of the coil in a direction orthogonal to the axial direction. The transformer according to claim 2, wherein the first frame body includes a plurality of elongated conductor materials disposed along each side of the rectangular parallelepiped; and the eddy current suppressing portion includes: a first insulating member; One of the plurality of vertices of the rectangular parallelepiped is a first apex; the second insulating member is disposed at a second apex at a diagonal position of the first apex; and the third insulating member is provided at The vertex of one of the first and second vertices is also the third vertex. The transformer according to claim 2, wherein the first frame body further includes: a plurality of strip-shaped conductor materials disposed along each side of the rectangular parallelepiped; and a plurality of eddy current suppressing portions provided in the plurality of eddy current suppressing portions A plurality of the strip-shaped conductor materials are insulated and bonded to a position corresponding to each vertex of the rectangular parallelepiped. The transformer according to claim 2, wherein a slit is formed in a direction orthogonal to a direction in which the eddy current flows in the surfaces of the first housing and the second housing. The transformer according to claim 2, wherein the first frame body and the second frame body are configured by an insulating member. The transformer according to claim 1, wherein the first housing has a pressing force adjustment unit that adjusts a pressing force to the coil.