JP2017208454A - Iron core support structure of current transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an iron core support structure of a current transformer, which supports the current transformer while suppressing deformation of a plurality of wound iron cores provided in parallel.SOLUTION: A current transformer is constructed by comprising: a wound iron core 10 formed by winding and laminating a band-like iron core material; and a frame part 30 that supports the winding to be inserted to the wound iron core and the wound iron core. The plurality of wound iron cores is provided so as to be arranged in a width direction of the band-like iron core materials. The frame part comprises a lower part frame 31 that sandwiches a lower end side of the plurality of wound iron cores from both sides of the width direction of the band-like iron core material. In the lower part frame, an outer side support frame 42 that supports both sides of a longitudinal direction orthogonal to the width direction in a lower surface of the wound iron core from a lower direction; and an inner side support frame 41 that supports a longitudinal direction near the central part from the lower direction.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a core support structure for a transformer, and more particularly to a core support structure for a transformer including an iron core in which a core material is wound in multiple layers.

  The transformer is a device that converts the voltage of AC power using electromagnetic induction, and includes an iron core that forms a magnetic circuit and a winding (coil) that forms an electric circuit. In such a transformer, an electromagnetic steel sheet or an amorphous alloy ribbon is used as the material of the iron core. Moreover, as a structure of the iron core, a wound iron core wound with these materials or a laminated iron core (also referred to as a stacked iron core) in which electromagnetic steel sheets are laminated in the horizontal direction is adopted.

  Conventionally, in a transformer using a wound iron core, for example, Patent Document 1 proposes a frame-shaped core fastener provided on the outer peripheral portions on both upper and lower sides of the wound iron core. In the lower core fastener in Patent Document 1, it is formed in a box shape having a rectangular bottom wall portion and side wall portions erected from four sides of the bottom wall portion, and accommodates a lower region of the wound core. Yes. Between the side wall portion of the core fastener and the laminated surface of the wound core, a coil base and a felt are disposed, and the dimensions of each member are set so that the wound core is sandwiched between the side wall portions.

Japanese Patent Laid-Open No. 2015-46456

  To increase the capacity of the transformer, etc., it is conceivable to increase the cross-sectional area of the iron core. In a transformer using a laminated iron core, the cross-sectional area of the iron core can be increased by increasing the width of the laminated electromagnetic steel sheets or increasing the number of laminated steel sheets. In supporting an iron core, the force to support the iron core in the stacking direction and the force to support the self-weight of the iron core are important. In the case of a laminated iron core stacked horizontally, the force to sandwich the iron core from the horizontal direction is important. The effect of supporting its own weight can also be obtained. On the other hand, in the wound core, there are more restrictions when the cross-sectional area is increased than in the laminated core, and in order to increase the capacity and the like, it is conceivable to arrange a plurality of wound cores in the width direction of the strip-shaped core material. However, in the case of a structure in which a plurality of wound cores are arranged in the width direction of the strip-shaped core material, a force is required to be sandwiched from both sides in the width direction of the strip-shaped core material so that the plurality of wound cores are integrated. There is a problem in that sufficient support force in the stacking direction cannot be obtained, and the lower part of the wound core is liable to be deformed by drooping or bending due to its own weight, resulting in deterioration of vibration characteristics and magnetic characteristics.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide a transformer core support structure that can support a plurality of wound cores arranged side by side while suppressing deformation. I will.

  An iron core support structure of a transformer according to one aspect of the present invention includes a wound iron core laminated by winding a belt-shaped iron core material, a winding inserted in the wound iron core, and a frame portion that supports the wound iron core. A plurality of the wound cores are provided side by side in the width direction of the belt-shaped core material, and the frame portion includes a lower frame that sandwiches the lower end sides of the plurality of wound cores from both sides in the width direction of the belt-shaped core material. A support frame is provided that supports both sides in the longitudinal direction perpendicular to the width direction on the lower surface of the wound core and the vicinity of the center from below.

  According to this configuration, the lower surface of the wound core can be supported over a wide range by the support frame while sandwiching and supporting the plurality of wound cores with the lower frame. As a result, deformations such as bending and sagging of the wound cores provided side by side can be suppressed, and noise characteristics can be improved while maintaining good magnetic characteristics.

  According to the iron core support structure of the transformer of the present invention, it is possible to keep a wide support area from below the wound core while applying the sandwiching force to the plurality of wound iron cores, thereby supporting the deformation by suppressing the deformation of each wound core. can do.

It is a front view which shows the principal part of the transformer with which the iron core support structure which concerns on this Embodiment is applied. It is the same front view as FIG. 1 which abbreviate | omitted the coil | winding. It is the sectional view on the AA line of FIG. FIG. 4 is a partially enlarged view of FIG. 3.

  Hereinafter, a transformer core support structure according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, below, the case where the iron core support structure which concerns on this invention is applied to a mold transformer is demonstrated. However, the application target of the iron core support structure according to the present invention is not limited to the mold transformer, and can be appropriately changed. For example, the present invention can be applied to dry transformers other than mold transformers (for example, Class H dry transformers), gas-insulated transformers, and oil-filled transformers.

  FIG. 1 is a front view showing a main part of a transformer to which the iron core support structure according to the present embodiment is applied. A transformer 1 shown in FIG. 1 includes a wound iron core 10 that constitutes a magnetic circuit, a winding (coil) 20 that constitutes an electric circuit, and a frame portion 30 that supports the wound iron core 10. FIG. 1 shows a transformer 1 having a three-phase three-leg structure in which a part of a wound core 10 inserted into three windings 20 is fixed to a pair of upper and lower frames 30 (31, 32). In addition, about the structure of the transformer used as the application object of this invention, it is not limited to this, It is applicable to the transformer 1 which has arbitrary structures, such as a 3 phase 5 leg structure.

  FIG. 2 is a front view similar to FIG. As shown in FIG. 2 in addition to FIG. 1, the wound core 10 is formed in a substantially rectangular shape in which a strip-shaped iron core material (amorphous alloy ribbon) is wound in multiple layers and the corners are quadrants when viewed from the front. Configured. More specifically, the wound core 10 is configured by winding an amorphous alloy ribbon having a thickness of 25 to 35 μm. The wound core 10 includes a pair of inner core portions 101 disposed on the inner side and an outer core portion 102 disposed on the outer side (outer peripheral side) of the inner core portions 101. Each inner iron core portion 101 is individually wound with an amorphous alloy ribbon. The outer iron core portion 102 is wound with an amorphous alloy ribbon with the inner iron core portion 101 disposed inside. The core material forming the wound core 10 is not limited to the amorphous alloy ribbon, but may be any other steel sheet such as a 0.2 to 0.4 mm thick steel sheet as long as it functions as the wound core 10. It is good also as a material.

  An opening 103 is formed at the center of each inner core portion 101 constituting the wound core 10. That is, the wound iron core 10 is formed with a pair of openings 103a and 103b penetrating perpendicularly to the stacking direction of the iron core material. These openings 103 may be referred to as window portions of the wound core 10. When the iron core material is an amorphous alloy ribbon, an electromagnetic steel sheet is provided on the inner periphery of the inner core portion 101 and the outer periphery of the outer core portion 102 to maintain the shape of the wound core 10 and to reinforce the wound core 10 itself. Is arranged.

  FIG. 3 is a cross-sectional view taken along line AA in FIG. As shown in FIG. 3, the wound core 10 is sometimes referred to simply as the “width direction” in the width direction of the amorphous alloy ribbon (strip-shaped core material) (the left-right direction in FIG. 3, the direction orthogonal to the stacking direction). Two are arranged side by side. The wound core 10 is disposed in a state where the respective laminated surfaces face each other and overlap each other. The two wound iron cores 10 are formed in a laminated body having substantially the same outer shape including the openings 103a and 103b when viewed from the front as shown in FIG. Here, the lower surface of the wound iron core 10 is formed in a rectangular shape, the short direction is the width direction (left-right direction in FIG. 3), and the longitudinal direction is the left-right direction in FIG. Then, both end edges in the longitudinal direction become a boundary portion between a flat area on the lower surface of the wound core 10 and a quadrant arc-shaped corner area.

  Returning to FIG. 1, the winding 20 has, for example, one inner winding 201 and two outer windings 202, and the entire surface of these windings 20 is covered with a resin or an insulating material containing resin. Has been. For example, an epoxy resin excellent in heat resistance and electrical insulation is used as the resin that covers the winding 20. Each of the windings 20 is disposed around the legs LG (LG1 to LG3) constituting the wound core 10. These windings 20 are positioned with respect to the frame portion 30 (31, 32) via the spacer member 21.

  The frame portion 30 includes a lower frame 31 provided at the lower end portion of the wound iron core 10 and an upper frame 32 provided at the upper end portion of the wound iron core 10.

  FIG. 4 is a partially enlarged view of FIG. As shown in FIG. 4, the lower frame 31 is provided on both the left and right sides in FIG. 4 of the unit when the two wound cores 10 are viewed as one unit. In other words, the lower region of the two wound cores 10 arranged side by side is supported so as to be sandwiched between the pair of lower frames 31. Each lower frame 31 is formed of a steel material or a sheet metal working material that is formed in a channel shape (U-shape) whose cross section is mainly constant and extends in the longitudinal direction. Specifically, a pressing surface portion 31 a oriented in the vertical direction along the laminated surface of the wound core 10, and an upper surface portion 31 b and a lower surface portion 31 c that protrude in the opposite direction to the wound core 10, and that are continuous above and below the pressing surface portion 31 a. It has.

  The connecting shaft 33 is provided through two positions at the top and bottom of the pressing surface portion 31a. A screw groove is formed on at least both ends of the connecting shaft 33, and a nut member (fastening member) 34 is provided in the screw groove so as to sandwich the pressing surface portion 31a from both sides. Therefore, by adjusting the screwing position of the nut member 34 with respect to the extending direction of the connecting shaft 33, the distance between the relative surfaces of the pressing surface portions 31a in the left and right lower frames 31 can be adjusted. A pinching force can be applied to the wound core 10 by 31a.

  As shown in FIG. 2, the lower frame 31 is provided with a length that protrudes from the left and right ends of the wound core 10 in FIG. And the connecting shaft 33 is the part which protruded, and is each provided in the left-right both ends vicinity in FIG.

  The lower frame 31 and the upper frame 32 are connected via four studs 35 extending in the vertical direction. The studs 35 are provided at approximately equal intervals in the left-right direction in FIG. The lower end portion of the stud 35 passes through an extended surface portion 31d (see FIG. 4) located on the same plane as the upper surface portion 31b of the lower frame 31. Reinforcing surface portions 31e are provided on the left and right sides of the extending surface portion 31d in FIG.

  As shown in FIG. 4, the reinforcing surface portion 31e is fixed to the inner surfaces of the pressing surface portion 31a, the upper surface portion 31b, and the lower surface portion 31c by welding or the like. A thread groove is formed at the lower end of the stud 35, and a nut member 36 is provided in the thread groove so as to sandwich the extended surface portion 31d from both sides.

  Here, as shown in FIG. 3, the upper frame 32 is substantially the same as the configuration in which the lower frame 31 is turned upside down and the vertical dimension is made larger than that of the lower frame 31. The upper frame 32 is sandwiched between the two. Similar to the lower frame 31, the upper frame 32 includes a pressing surface portion 32a, an upper surface portion 32b, and a lower surface portion 32c, and extends in the direction perpendicular to the paper surface of FIG. The connecting shaft 33 is also provided at three positions above and below the pressing surface portion 32a in the same manner as the pressing surface portion 31a. The screw cores of the nut members 34 provided at both ends of the connecting shaft 33 are adjusted to adjust the winding core. A pinching force can be applied to 10. In FIG. 2, the left and right positions of the connecting shaft 33 in the upper frame 32 are the same as the left and right positions of the connecting shaft 33 in the lower frame 31.

  The upper end portion of the stud 35 passes through the extended surface portion 32d located on the same plane as the lower surface portion 32c of the upper frame 32. A thread groove is also formed at the upper end portion of the stud 35, and a nut member 36 is provided in the thread groove so as to sandwich the extended surface portion 32d from both sides. The distance between the lower frame 31 and the upper frame 32 can be adjusted by adjusting the screwing position of the nut member 36 with respect to the stud 35. Reinforcing surface portions 32e are also provided on the left and right sides of the upper frame 32 in FIG.

  As shown in FIG. 2, two inner support frames (support frames) 41 and two outer support frames (support frames) 42 are provided on the lower surface portion 31 c of the lower frame 31. The inner support frame 41 and the outer support frame 42 are formed of a steel material or a sheet metal processing material that is formed in a channel shape (U-shape) whose cross section is mainly constant and extends in the longitudinal direction (the direction orthogonal to the paper surface in FIG. 2). The Specifically, pressure receiving surface portions 41a and 42a oriented horizontally along the lower surface of the wound core 10, and side surface portions 41b and 42b projecting downward from the left and right sides in FIG. 2 of the pressure receiving surface portions 41a and 42a, and It has. The side surface portion 42 b of the outer support frame 42 is formed to have a larger vertical dimension than the side surface portion 41 b of the inner support frame 41. The outer support frame 42 is provided with a moving mechanism including wheels and the like that support the movement of the transformer 1, holes for installation and fixing, and the like (not shown).

  In FIG. 2, the inner support frame 41, the outer support frame 42, and the inner support frames 41 that are adjacent to each other on the left and right are arranged side by side in a state where they are in contact with each other or have a slight gap interposed therebetween. Support over the area. The pressure-receiving surface portion 42a of the outer support frame 42 straddles both ends in the longitudinal direction (left-right direction) of the lower surface of the wound core 10, in other words, supports both sides in the longitudinal direction of the wound core 10 from below. Further, since the pressure receiving surface portion 41a of the inner support frame 41 is disposed between the two outer support frames 42, the vicinity of the central portion in the longitudinal direction of the wound core 10 is supported from below. The inner support frame 41 may be at least partially disposed at a position directly below the leg portion LG <b> 2 inside the wound iron core 10. Further, it is preferable that at least a part of the outer support frame 42 is disposed at a position directly below the leg portions LG1 and LG3 on the outer side of the wound core 10.

  As shown in FIG. 4, the extending direction of the inner support frame 41 and the outer support frame 42 is directed in the width direction of the wound core 10 (left and right direction in FIG. 4). The outer support frame 42 is longer in the extending direction than the inner support frame 41, and the extending direction length of the outer support frame 42 is a length that protrudes from the pair of lower frames 31 in the left-right direction in FIG. Is set. Further, the length of the inner support frame 41 in the extending direction is set to a length that makes contact with the lower surface portions 31 c of the pair of lower frames 31 according to the width-direction dimension of each wound core 10.

  The inner support frame 41 and the outer support frame 42 are detachably attached to the lower surface portion 31c of the lower frame 31 via bolts 44 and nuts 45 serving as attachment members. In the pressure receiving surface portions 41a and 42a or the lower surface portion 31c, holes that penetrate the bolts 44 are slot holes (not shown), and the left and right positions in FIG. 4 of the support frames 41 and 42 with respect to the lower surface portion 31c can be adjusted. .

  A damping member 47 is provided between the wound core 10 and the inner support frame 41 and the outer support frame 42. The damping member 47 is composed of a sheet member made of an elastic material such as ethylene, propylene, and diene rubber (EPDM), and can absorb and attenuate the vibration of the wound core 10 due to excitation vibration or the like. As a result, even if vibration is generated in the wound core 10, such vibration is prevented from propagating to the inner support frame 41 and the outer support frame 42, and the wound core 10 is prevented from striking the support frames 41, 42 by vibration. As a result, the generation of noise can be suppressed.

  According to such an embodiment, by screwing the nut member 34 into the connecting shaft 33, a pulling force is exerted between the opposed lower frames 31 and between the upper frames 32. Can be sandwiched from both sides in the width direction. Moreover, the substantially entire region of the lower surface of the wound core 10 is supported from below by the inner support frame 41 and the outer support frame 42. Thereby, the deformation | transformation of the lower area | region and lower surface which becomes easy to generate | occur | produce a bending | deflection, dripping, etc. on the property of the wound core 10 used as the laminated structure wound by the amorphous alloy ribbon etc. can be suppressed. As a result, it is possible to avoid the deterioration of the magnetic characteristics of the wound iron core 10, and furthermore, it is possible to improve the noise characteristics by suppressing the generation of excitation sound accompanying the deterioration of the magnetic characteristics of the wound iron core 10.

  Further, since the inner support frame 41 and the outer support frame 42 extend in the width direction of the wound core 10, it is easy to change the width direction dimension of the wound core 10 by forming each support frame 41, 42 in advance. Can respond. Moreover, it becomes easy to use the member which formed rib-shaped parts, such as side part 41b, 42b, in the same direction as the extension direction, and the rigidity of each support frame 41, 42 is improved, and the lower surface of the wound core 10 is favorably viewed from below. Can be supported.

  Further, since the lower frame 31 and the upper frame 32 sandwich the wound core 10 by tightening the nut member 34 with respect to the connecting shaft 33, the sandwiching force can be applied to the wound core 10 with a simple configuration.

  Further, since the inner support frame 41 and the outer support frame 42 are attached to the lower surface side of the lower frame 31 via bolts 44 and nuts 45, the support frames 41 and 42 can be attached to and detached from the lower frame 31. . Therefore, the mounting process can be simplified as compared with the case where they are fixed by welding. Moreover, since the mounting position can be adjusted in the extending direction of the slot hole through which the bolt 44 passes, it is possible to easily cope with the change in the width direction dimension of the wound core 10.

  In addition, this invention is not limited to the said embodiment, It can implement variously. In the above-described embodiment, the size, shape, direction, and the like illustrated in the accompanying drawings are not limited thereto, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  For example, in the above embodiment, two wound iron cores 10 are arranged side by side in the width direction, but a plurality of three or more bodies are arranged side by side so as to be sandwiched and supported by the frame portion 30 (the lower frame 31 and the upper frame 32). It may be.

  Further, the inner support frame 41 may be provided as a single body with the left-right width expanded in FIG. Furthermore, as long as the center part in the left-right direction in FIG. 2 on the lower surface of the wound iron core 10 is supported, the gaps between the inner support frame 41, the outer support frame 42, and the inner support frame 41 that are adjacent to the left and right are increased or decreased. May be changed.

  Further, the direction of the inner support frame 41 is changed so that both ends in the extending direction are connected to the outer support frame 42 as directions extending in the longitudinal direction (left and right direction in FIG. 2) on the lower surface of the wound core 10. Good. In this case, the inner support frame 41 is supported by the lower frame 31 via the outer support frame 42.

  Further, the inner support frame 41 and the outer support frame 42 can be variously modified as long as the wound core 10 can be supported in the same manner as in the above embodiment. It may be a letter shape or an L shape.

  Moreover, in the Example of this application, although the tripod iron core which combined two or more wound iron cores is illustrated, the two-leg iron core comprised by the single winding, the five-leg iron core which combined several winding iron cores, etc. were used. Even in the case, the same effect can be obtained.

DESCRIPTION OF SYMBOLS 1 Transformer 10 Winding iron core 20 Winding 30 Frame part 31 Lower frame 33 Connecting shaft 34 Nut member (fastening member)
41 Inside support frame (support frame)
42 Outer support frame (support frame)
47 Damping member

Claims (7)

A wound core laminated by winding a belt-shaped iron core material, a winding inserted in the wound core, and a frame portion that supports the wound core,
A plurality of the wound cores are provided side by side in the width direction of the strip-shaped core material,
The frame portion includes a lower frame that sandwiches the lower end side of the plurality of wound cores from both sides in the width direction of the belt-shaped iron core material, both longitudinal sides perpendicular to the width direction on the lower surface of the wound core, and the vicinity of the central portion. An iron core support structure for a transformer, characterized in that a support frame for supporting from below is provided.   The said support frame is supported over the substantially whole area | region in the lower surface of the said wound iron core, The iron core support structure of the transformer of Claim 1 characterized by the above-mentioned.   The said support frame is extended in the width direction of the said strip | belt-shaped iron core material, and is attached to the lower surface side of the said lower frame, The iron core support structure of the transformer of Claim 1 or Claim 2 characterized by the above-mentioned.   The lower frames positioned on both sides in the width direction of the belt-shaped iron core material are connected via a connecting shaft, and a pinching force by the lower frame is applied to the wound iron core by a fastening member provided on the connecting shaft. The iron core support structure for a transformer according to any one of claims 1 to 3.   The transformer core support structure according to any one of claims 1 to 4, wherein a damping member is provided between the wound core and the support frame.   6. The transformer core support structure according to claim 5, wherein the damping member is formed of a sheet member made of an elastic body. The transformer core support structure according to any one of claims 1 to 6, wherein the wound iron core is formed by winding an amorphous alloy ribbon.

Images