JP2016063140A - Iron-core tightening device and stationary induction apparatus having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an iron-core tightening device capable of suppressing eddy current loss and heat generation caused by the concentration of an eddy current in a lower iron-core tightening metal fitting for tightening a lower yoke section of a laminated iron core.SOLUTION: An iron-core tightening device 2, having a lower iron-core tightening metal fitting 202 for tightening a lower yoke section 102 of a laminated iron core 1, includes a slit 207 for inhibiting an eddy current from concentrating on a position (a base 206 of a lower tightening plate 2021) on which an eddy current of the lower iron-core tightening metal fitting 202 concentrates.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an iron core fastening device for fastening a yoke part of a laminated iron core and a stationary induction device including the iron core fastening device.

  Conventionally, a transformer using a laminated iron core is known. For example, Patent Document 1 discloses a transformer using a laminated core having a structure shown in FIG.

  A laminated core 300 shown in FIG. 12 is a laminated core for a three-phase transformer. An upper yoke portion 301D and a lower yoke portion 301E of an iron core 301 formed by laminating a plurality of steel plates are respectively connected to an upper core fastening bracket 302A and a lower portion. It has a structure that is clamped in the stacking direction (direction perpendicular to the paper surface) with the iron core fastening bracket 302B. The iron core 301 has three legs 301A, 301B, and 301C, and U-phase, V-phase, and W-phase windings 303A, 303B, and 303C are wound around the legs 301A, 301B, and 301C, respectively. .

Japanese Patent Laid-Open No. 06-188128 (paragraph [0017], FIG. 1 etc.)

  In the laminated core 300 having the structure shown in FIG. 12, the leakage flux of magnetic flux generated by the alternating current flowing through the windings 303A, 303B, and 303C links the upper core fastening bracket 302A and the lower core fastening bracket 302B, and the upper core clamping. Eddy currents are generated in the attachment fitting 302A and the lower iron core fastening fitting 302B.

  Upper iron core fastening bracket 302A and lower iron core fastening bracket 302B generally include a pair of metal plates sandwiching an iron core in which a plurality of steel plates are laminated, and the metal plate has a portion where eddy currents flow in a concentrated manner depending on the shape of the metal plates. Occurs.

  For this reason, there is a problem that a large eddy current loss is locally generated at a portion where the eddy current of the metal plate is concentrated and heat generation is increased.

  The iron core fastening device according to the first aspect of the present invention is an iron core fastening device including a lower iron core fastening member for fastening a lower yoke portion of a laminated iron core, wherein the eddy current of the lower iron core fitting is concentrated at a location where the eddy current is concentrated. An iron core fastening device, wherein a predetermined structure that inhibits current concentration is provided.

  With this configuration, it is possible to reduce eddy current loss and heat generation due to eddy current concentration in the lower iron core fastener.

  Further, in the iron core fastening device of the second invention, in contrast to the first invention, the lower iron core fastening fitting has a winding wound around the leg portion at a position corresponding to the leg portion of the laminated iron core. An iron core fastening device having a pedestal to be placed and having a predetermined structure is provided on the pedestal.

  With such a configuration, it is possible to prevent local concentration of eddy current generated in the pedestal portion of the lower iron core fastening bracket.

  Further, the iron core clamping device according to the third invention is an iron core clamping device in which the predetermined structure is a structure in which a slit extending in the direction of the leg portion from the outer edge is provided on the pedestal with respect to the second invention. is there.

  Moreover, the iron core fastening apparatus of this 4th invention is an iron core fastening apparatus with which the slit is provided so that a base may be divided into 2 with respect to 3rd invention.

  With this configuration, the third and fourth inventions can disperse or reduce eddy currents generated in the pedestal.

  Further, in the iron core clamping device of the fifth invention, an insulator is provided between the pedestal and the winding placed on the pedestal with respect to the third or fourth invention. This is an iron core tightening device in which a protrusion that fits into a slit provided in the pedestal is formed.

  With this configuration, the fifth aspect of the present invention can reduce the leakage magnetic flux interlinking the pedestal of the lower iron core fastening bracket, thereby reducing the eddy current generated in the pedestal.

  Further, in the iron core tightening device of the sixth invention, the pedestal has a polygonal shape with respect to any one of the second to fifth inventions, and the predetermined structure has chamfered corners of the pedestal. Thus, the iron core clamping device has a structure in which curved surfaces are formed at the corners.

  With this configuration, it is possible to prevent eddy currents from concentrating on the corners of the pedestal.

  Further, in the iron core tightening device of the seventh invention, in contrast to the second invention, the lower iron core fastening bracket comprises a pair of lower tightening plates sandwiching the lower yoke part of the laminated iron core, and the laminated iron core. A clamp for fastening the pair of lower fastening plates sandwiched therebetween, and a pair provided at both ends of the pair of lower fastening plates for connecting one lower fastening plate and the other lower fastening plate The predetermined structure is an iron core clamping device having a structure in which a gap is provided in a connecting portion that connects the lower clamping plate and the coupling member.

  With this configuration, it is possible to prevent eddy currents from concentrating on the connecting portion between the lower iron core fastening bracket and the connecting member.

  Moreover, the iron core clamping device of this 8th invention is an iron core clamping device with which the clearance gap is further filled with the insulating member with respect to 7th invention.

  With this configuration, it is possible to prevent eddy currents from concentrating on the connecting portion between the lower iron core fastening bracket and the connecting member.

  The static induction device according to the ninth aspect of the present invention is a static induction device comprising a laminated iron core and a winding wound around a leg portion of the laminated iron core. It is the stationary induction apparatus characterized by being clamped by any one of the iron core clamping devices of the invention.

  With this configuration, it is possible to reduce eddy current loss and heat generation that occur in the iron core clamping device of the stationary induction device.

  The static induction device according to the tenth aspect of the invention is a transformer.

  With this configuration, it is possible to reduce eddy current loss and the amount of heat generated in the transformer core clamping device.

  According to the iron core fastening device of the present invention, local eddy current loss and heat generation in the lower iron core fastening fitting can be reduced.

Front view of transformer main body (configuration in which windings of each phase of U, V, W are wound around a laminated core) housed in a transformer tank Top view of the transformer body Right side view of the transformer body The figure which shows the structure of the base provided with the slit The figure which shows the structure of the connection part of a lower clamping plate and a lower connection member The figure which shows the modification of the structure of the connection part of a lower clamping plate and a lower connection member The figure which showed typically an example of the leakage magnetic flux which links the base of this Embodiment 1, and the eddy current which flows through a base The figure which showed typically an example of the leakage magnetic flux which links the connection part of the lower fastening plate and lower connection member of this Embodiment 1, and the eddy current which flows through a lower fastening plate and a lower connection member The figure which shows the example which provided the mounting base which consists of insulators between a base and a coil | winding Diagram showing the mounting structure of the mounting table to the pedestal The figure which shows the example which provided the protrusion part inserted in the slit of a base on a mounting base Diagram showing the structure of a conventional laminated core

  Hereinafter, an embodiment of an iron core fastening device according to the present invention will be described with reference to the drawings.

(Embodiment 1)
In the first embodiment, a laminated iron core of a three-phase transformer using the iron core fastening device according to the present invention will be described as an example.

  FIG. 1 is a front view of a transformer main body A (a configuration in which windings of U, V, and W phases are wound around a laminated iron core) housed in a transformer tank, and FIG. FIG. 3 is a right side view of the transformer main body A. FIG.

  The transformer main body A includes a laminated iron core 1 formed by laminating a plurality of steel plates (for example, silicon steel plates), an iron core fastening device 2 for fastening the laminated iron core 1 in a laminating direction (a direction perpendicular to the paper surface in FIG. 1), Includes three windings 3U, 3V, 3W. The laminated core 1 has three leg portions 103U, 103V, 103W, an upper yoke portion 101 that connects the upper portions of these leg portions 103U, 103V, 103W, and a lower portion of the three leg portions 103U, 103V, 103W. And a lower yoke portion 102. In the laminated core 1, the cross-sectional shapes of the three leg portions 103U, 103V, and 103W are made substantially circular by changing the dimensions of the steel plates to be laminated.

  The windings 3U, 3V, and 3W are wound around the leg portions 103U, 103V, and 103W, respectively. The U-phase winding 3U includes, for example, a high voltage winding (primary winding; not shown) to which a high voltage of 6600 volts is input and a low voltage winding (secondary winding) from which a low voltage of 100 volts is output. (Not shown). The high-voltage winding and the low-voltage winding of the winding 3U are respectively wound in a cylindrical shape, and both windings are attached to the leg 103U so that the high-voltage winding is wound concentrically outside the low-voltage winding. It is wound. The V-phase winding 3V and the W-phase winding 3W have the same configuration as the U-phase winding 3U. In the following description, when the leg portions 103U, 103V, and 103W are represented, the reference numeral “leg portion 103” is used, and when the winding portions 3U, 3V, and 3W are represented, “winding 3 This will be described using the symbol "."

  The iron core fastening device 2 includes an upper iron core fastening fitting 201 for fastening the upper yoke part 101 of the laminated iron core 1, a lower iron core fastening metal fitting 202 for fastening the upper yoke part 101 of the laminated iron core 1, and an upper iron core fastening metal fitting. 201 and a connecting plate 203 for connecting the lower iron core fastening bracket 202 to each other. The upper iron core fastening fitting 201 connects two upper fastening plates 2011, 2012 sandwiching the longitudinal side surface (upper and lower side surfaces in FIG. 2) of the upper yoke portion 101 and both ends of the upper fastening plates 2011, 2012. It consists of two upper connecting members 2013.

  The upper clamping plate 2011 is configured by a belt-like plate member having a U-shaped cross section (see FIG. 3), and is arranged at a predetermined position in the longitudinal direction (a position where the upper clamping plate 2011 is divided into approximately four equal parts). Reinforcing pieces 2011a are provided. The upper clamping plate 2012 also has the same shape and structure as the upper clamping plate 2011.

  The upper yoke part 101 of the laminated core 1 is fastened by tightening the upper yoke part 101 with an upper fastening plate 2011 and an upper fastening plate 2012.

  The upper connecting member 2013 is also composed of a belt-like plate member having a U-shaped cross section similar to that of the upper fastening plate 2011 (see FIG. 3). Fixing surfaces 2013a for fixing to the upper fastening plate 2011 and the upper fastening plate 2012 are formed at both ends of the upper connecting member 2013 (see FIG. 3). Both fixed surfaces 2013a are formed by bending.

  The two upper connecting members 2013 have a predetermined length (substantially the same length as the distance between the two fastening plates 2011 and 2012 when the laminated core 1 is fastened by the upper fastening plate 2011 and the upper fastening plate 2012). Both end surfaces are fixed to the upper fastening plate 2011 and the upper fastening plate 2012 by bolting.

  Two hooks 211 are attached to the upper fastening plate 2011 at a position inside the reinforcing pieces 2011a on both sides. The hook 211 is a plate-like member extending upward, and has a hole at the upper end. The hook 211 is a metal fitting for hanging the transformer main body A when the transformer main body A is taken in and out of the tank. The upper fastening plate 2012 also has the same shape and structure as the upper fastening plate 2011, and two hooks 211 are attached at positions inside the reinforcing pieces (not shown) on both sides.

  In addition, a connecting member 204 is attached to the upper surfaces of the upper fastening plate 2011 and the lower fastening plate 2012 in order to reinforce the strength of the upper core fastening fitting 201.

  Similarly to the upper core clamp 201, the lower core clamp 202 connects the two lower clamp plates 2021, 2022 sandwiching the longitudinal side surface of the lower yoke portion 102 and both ends of the lower clamp plates 2021, 2022. And two lower connecting members 2023. The fastener 2023 is also made of a metal bolt and nut, and is a fastener that fastens the laminated core 1 by bolting.

  Similarly to the upper fastening plate 2011, the lower fastening plate 2021 is formed of a belt-like plate member having a U-shaped cross section, and two reinforcing pieces are provided at positions corresponding to the three leg portions 103U, 103V, and 103W. 2021a is provided. The lower fastening plate 2022 has the same shape and configuration as the lower fastening plate 2021.

  Three fixing members 205 for fixing the transformer main body A to a support member in the tank are provided below the lower fastening plate 2021 and the lower fastening plate 2022. The three fixing members 205 are provided at positions corresponding to the three leg portions 103U, 103V, and 103W in a direction orthogonal to the lower yoke portion 102 (see FIG. 3). A pair of plate members 205a for supporting the fixing member 205 is attached to each of the lower surface of the lower fastening plate 2021 and the lower fastening plate 2022, and each fixing member 205 is placed horizontally at the tip of the plate member 205a. Is attached.

  The upper fastening plate 2011 and the lower fastening plate 2021 are connected by three connecting plates 203. The upper fastening plate 2012 and the lower fastening plate 2022 are also connected by three connecting plates 203. The connection position of each connection plate 203 is a position corresponding to the three leg portions 3U, 3V, 3W of the laminated core 1. The connecting plate 203 is a metallic plate member, and both ends of the connecting plate 203 are welded to the upper fastening plate 2011 and the lower fastening plate 2021.

  A total of six trapezoidal pedestals 206 are attached to the upper surfaces of the lower fastening plate 2021 and the lower fastening plate 2022 so as to project outward at positions corresponding to the three leg portions 103U, 103V, 103W. Yes. The pedestal 206 is fixed to the upper surface of the lower fastening plate 2021 by welding. The pedestal 206 is a member for placing three windings 3U, 3V, 3W wound around the three leg portions 103U, 103V, 103W.

  As shown in FIG. 4, the corner portion 206a on the front end side of the projecting base 206 is chamfered so as to form a curved surface. The reason why the curved surface is formed in the corner portion 206a of the pedestal 206 is to prevent the eddy current from concentrating on the corner portion 206a when the eddy current flows through the pedestal 206. 4A and 4B are diagrams showing the structure of the pedestal 206 on which the V-phase winding 3V attached to the center of the lower fastening plate 2021 is placed, wherein FIG. 4A is a top view, and FIG. 4B is a front view. (C) is a right side view.

In addition, a slit 207 extending in the direction from the outer edge toward the leg 3V corresponding to the pedestal 206 is provided at the approximate center of the pedestal 206. The slit 207 is provided on the entire seating surface so as to bisect the pedestal 206. A curved surface is also formed by a chamfering process at a corner 206a at the tip of the slit 207 generated by providing the slit 207. The slit 207 is for interrupting the current path when eddy current flows through the pedestal 206 and reducing dispersion and concentration of the eddy current. For example, if there is no slit 207, an eddy current i _e that flows in a current path indicated by a one-dot chain line is generated in the pedestal 206, but if the slit 207 is provided so as to cut the current path, the eddy current i _e is , now flows through a current path indicated by the solid line, it is possible to reduce the concentration of the eddy current i _e dispersion and based thereon eddy currents i _e. The chamfering process of the corner 206a of the base 206 and the operation / effect of the slit 207 will be described later.

  In the first embodiment, the shape of the pedestal 206 is a trapezoid, but may be a polygon other than a trapezoid such as a rectangle or a square. Also in this case, it is preferable to form a curved surface at the corner 206a generated by providing the slit 207 in the polygon corner 206a or the pedestal 206.

  The two lower connecting members 2023 have the same shape and structure as the upper connecting member 2013. Fixing surfaces 2023a for fixing to the lower fastening plate 2021 and the lower fastening plate 2022 are formed at both ends of the lower connecting member 2023 by bending, but the length of the lower connecting member 2023 is the upper connecting plate. It is set shorter than the member 2013. As shown in FIG. 5, the length of the lower connecting member 2023 is shorter than that of the upper connecting member 2013. The lower connecting member 2023 is connected to the lower fastening plate 2021 and the lower fastening plate via spacers 208 made of an insulator. This is for connection to the attached plate 2022. In other words, the lower fastening plate 2021 and the lower fastening plate 2022 are insulated from the lower connecting member 2023. For the spacer 208, for example, a resin such as Teflon (registered trademark), silicon, or phenol resin, or wood such as plywood is used.

  The fixing surfaces 2023a at both ends of the lower connecting member 2023 are fixed to the lower fastening plate 2021 and the lower fastening plate 2022 by screwing with a fastener 209 made of a metal bolt and nut. In this screw fastening, in order to insulate the fastener 209 from the lower fastening plate 2021, the lower fastening plate 2022, and the lower connecting member 2023, the bolt of the fastener 209 covers a cylindrical cover 209b made of an insulating member. The lower fastening plates 2021 and 2022, the fixing surface 2023a, and the bolt holes of the spacer 208 are fitted and installed. In addition, washers 209a made of insulating members are attached to the heads of the bolts and the insides of the nuts.

  Since the lower connecting member 2023, the lower fastening plate 2021, and the lower fastening plate 2022 are insulated by the spacer 208, the eddy current flowing between the lower fastening plate 2021, the lower fastening plate 2022, and the lower connecting member 2023. Can be reduced.

  In the first embodiment, the spacer 208 is filled in the entire space between the lower fastening plate 2021 and the lower fastening plate 2022 and the lower connecting member 2023. However, as shown in FIG. 209 may be provided only in the bolt portion, and the clearance 212 may be provided between the lower fastening plate 2021 and the lower fastening plate 2022 and the lower connecting member 2023. In this case, when the transformer main body A is stored in the tank, the insulating oil enters the gap, so that the insulating oil allows the lower fastening plate 2021, the lower fastening plate 2022, and the lower connecting member 2023 to be connected. While reducing the eddy current which flows, the heat_generation | fever by the eddy current can be suppressed.

  A pedestal 210 is attached to each of the upper surfaces of the two lower connecting members 2023. A base 210 attached to the lower connecting member 2023 facing the leg 103U is a member for placing the winding 3U wound around the leg 103U, and a base attached to the lower connecting member 2023 facing the leg 103W. Reference numeral 210 denotes a member for placing the winding 3W wound around the leg 103W. Since the eddy current flowing between the lower fastening plate 2021 and the lower fastening plate 2022 and the lower connecting member 2023 is reduced by the spacer 208, the base 210 is not provided with a slit.

  Next, the operation and effect of the iron core tightening device 2 of the first embodiment will be described.

  Since the three-phase AC voltage is applied to the high-voltage windings (primary windings) of the windings 3U, 3V, and 3W, currents having phases different from each other by 2π / 3 flow through the high-voltage windings. For example, when a V-phase current flowing through the center winding 3V is used as a reference, a current delayed by 2π / 3 with respect to the V-phase current flows in the U-phase winding 3U, and the W-phase winding 3W Flows a current advanced by 2π / 3 with respect to the V-phase current.

  The eddy current flows on the surface of the pedestal 206 due to the skin effect, and is concentrated on the pointed portion. Therefore, in the central pedestal 206, the eddy current tends to flow concentrated on the corner of the trapezoid.

Figure 7 is a diagram of an example of an eddy current i _e which flows through the leakage flux φ and the pedestal 206 to base 206 of the first embodiment interlinked schematically showing. FIG. 7 shows an example in which the leakage flux φ links the pedestal 206 downward from the upper side.

As shown in FIG. 7, when the leakage flux φ links the pedestal 206 downward from the upper side, the counterclockwise eddy current i _e is generated in the pedestal 206 so as to generate a magnetic flux that weakens the leakage flux φ. Flowing. If the slit 207 is not provided in the pedestal 206, the eddy current i _e freely flows on the surface of the mounting surface of the winding 3 of the pedestal 206 by the skin effect. Since the current density of the eddy current i _e varies depending on the distribution of the leakage magnetic flux φ, the shape of the pedestal 206, and the like, a portion where the eddy current i _e is concentrated on the pedestal 206 is generated.

Since the pedestal 206 of the first embodiment is provided with the slit 207 in the center, for example, the eddy current i _e that flows through the current path indicated by the alternate long and short dash line is interrupted by the slit 207, and the eddy indicated by the solid line Dispersed in current i _e . In addition, since the corner portion 206a of the base 206 is chamfered to form a curved surface, the density of eddy current flowing through the corner portion 206a is reduced.

Therefore, according to the attached core clamping device 2 of the first embodiment, in the three seat 206 of the lower clamping plate 2021, an eddy current i _e to reduce the heat generation and eddy current loss caused by local concentration be able to.

Figure 8 is an example of an eddy current i _e which flows through the connecting portion with the leakage magnetic flux φ interlinked lower clamping plate 2021 and the lower coupling member 2023 of the lower clamping plate 2021 and the lower connection member 2023 of the first embodiment It is the figure shown typically.

  For example, at the end of the lower core fastening metal 202 on the leg 103W side, the leakage flux φ links the lower fastening plate 2021, the lower connecting member 2023, and the lower fastening plate 2022 in the same direction. FIG. 8 shows an example in which the leakage flux φ is linked from the upper side to the lower direction. However, the leakage flux φ is also tightened in the lower direction when linking from the lower side to the upper direction or in the lateral direction. The attached plate 2021, the lower fastening plate 2022, and the lower connecting member 2023 are linked in the same direction.

As shown in FIG. 8, when the leakage flux φ links the lower fastening plate 2021 and the lower connecting member 2023 downward from above, the lower fastening plate 2021 and the lower connecting member 2023 are connected in a conductive state. For example, a counterclockwise eddy current i _e flows through the lower fastening plate 2021 and the lower connecting member 2023 so as to generate a magnetic flux that weakens the leakage magnetic flux φ.

For example, when the eddy current i _e flows in a path that circulates between the lower fastening plate 2021 and the lower connecting member 2023 as indicated by the alternate long and short dash line, the lower fastening plate 2021 and the lower connecting member 2023 are orthogonal to each other. Therefore, the eddy current i _e is concentrated at the corner where the current path changes at a right angle.

In the lower tightening plate 2021 of the first embodiment, the lower tightening plate 2021 and the lower connecting member 2023 are insulated by the spacer 208 made of an insulating material. For example, the current flows in a current path indicated by a one-dot chain line. The eddy current i _e to be cut off is blocked by the spacer 208 and dispersed into the eddy current i _e indicated by the solid line. Therefore, it is possible to reduce eddy current loss and heat generation due to eddy currents concentrating on the connecting portions of the lower fastening plate 2021 and the lower connecting member 2023. The same operation and effect as described above can be obtained at both the connecting portions of the lower fastening plate 2022 and the lower connecting member 2023 and the end of the lower core fastening fitting 202 on the leg 103U side.

As described above, according to the attached core clamping device 2 of the first embodiment, the portion where the eddy current i _e in the lower core Clamping fixture 202 are concentrated, the predetermined structure to inhibit concentration of the eddy current i _e since is provided, it is possible to suitably prevent heat generation and local eddy current loss due to concentration of eddy current i _e.

Specifically, a slit 207 is provided on the base 206 of the lower clamping plate 2021 and the lower clamp plate 2022, since so as to block the path of the eddy currents _{i e} in the seat 206 at the slit 207, eddy current i The path of _e is dispersed, the concentration of eddy current i _e in the pedestal 206 is reduced, and local eddy current loss and heat generation in the pedestal 206 can be reduced. In addition, since the insulating oil for cooling and insulating enters the slit 207, the heat generated by the eddy current can be reduced by the insulating oil.

In addition, a spacer 208 made of an insulating member is interposed between the lower fastening plate 2021 and the lower fastening plate 2022 and the lower connecting member 2023 so that the lower fastening plate 2021, the lower fastening plate 2022, and the lower connecting member 2023 are connected to each other. since so as to block the path of the eddy currents i _e during, not flow in a path eddy currents i _e circulates between the lower clamping plate 2021 and the lower clamping plate 2022 and the lower connecting member 2023 Further, local eddy current loss and heat generation due to concentration of the eddy current i _{e at} the connecting portion between the lower fastening plate 2021 and the lower fastening plate 2022 and the lower connecting member 2023 can be reduced.

In FIG. 1 to FIG. 4, the slit 207 is provided only on the pedestal 206 as a whole, and only the pedestal 206 is bisected. May be. Thus if you can also restrict the flow of eddy currents i _e at the portion where the seat 206 dated lower clamping plate 2021 and 2022 are mounted (horizontally bent portion of the top).

  1 to 4, the slit 207 is provided in the entire pedestal 206, but the slit 207 may be provided in a part of the pedestal 206. For example, in FIG. 4, a slit 207 is provided only in a portion protruding from the lower fastening plate 2021 of the pedestal 206, and no slit 207 is formed in a portion welded to the lower fastening plate 2021 of the pedestal 206. Good.

  1 to 4, only one slit 207 is provided on the pedestal 206, but two or more slits 207 may be provided. In this case, all the slits 207 may be cut from the outer edge of the pedestal 206 toward the leg 3 corresponding to the pedestal 206, and some or all of the slits 207 are in the shape of long holes in the pedestal 206. It may be formed.

  1 to 4, when the slit 207 is a space and the transformer main body A is accommodated in a tank filled with insulating oil, the insulating oil enters the slit 207. The structure filled with may be sufficient.

  1-4, the pedestal 206 is provided with slits 207 to inhibit the eddy current path flowing through the pedestal 206, thereby reducing the concentration of eddy currents. As described above, a mounting table 212 made of an insulating member may be interposed between the base 206 and the winding 3 mounted on the base 206. By interposing the mounting table 212, the coils 3U, 3V, 3W and the lower iron core fastening bracket 202 can be reliably insulated. As the mounting table 212, for example, wood or phenol resin (bakelite) may be used.

  The examples of FIGS. 9 and 10 are examples in which a rectangular parallelepiped mounting table 212 is fixed to a base 206 with a fastener 213 composed of wooden bolts 213a and nuts 213b. Since the bolt 213a of the fastener 213 is attached so as to cross the pedestal 206, the fastener 213 is also made of an insulator (for example, wooden) so that no eddy current is generated in the fastener 213.

When the mounting table 213 made of an insulating member is interposed between the pedestal 206 and the winding 3, the winding 3 is separated from the pedestal 206, so that the leakage magnetic flux φ interlinking the pedestal 206 is less than the case where the mounting table 213 is not provided. Less. Thus, the magnitude of the eddy currents i _e which occurs seat 206 is small, it is possible to suppress the locally generated eddy current loss and heat generation in the base 206.

  In the example of FIGS. 9 and 10, the mounting table 212 has a rectangular parallelepiped shape, and the slit 207 of the pedestal 206 is a space, but the convexity that fits into the slit 207 at a position facing the slit 207 on the lower surface of the mounting table 212. A portion 212 a may be formed, and the slit 207 may be closed by the convex portion 213 a of the mounting table 212.

  When the mounting table 212 is provided on the pedestal 206, either or both of the formation of the slit 207 and the chamfering process of the corner portion 206a may be performed on the pedestal 206, or neither of them may be performed.

In the example of FIGS. 1 to 4, the windings 3U, 3V, and 3W are mounted on the six bases 206 of the lower core fastening metal fitting 202, and therefore the windings 3U, 3V, and 3W are fastened to the lower core. Although it is in a state of being in close contact with the metal fitting 202, it is in a state of being slightly separated from the upper iron core fastening metal fitting 201. Therefore, the leakage magnetic flux φ interlinked lower core Clamping fixture 202, becomes larger than the leakage magnetic flux φ interlinked upper core Clamping fixture 201, Ya locally eddy current loss due to the concentration of the eddy current i _e A location where heat generation increases tends to occur on the lower core fastening metal fitting 202 side.

In the first embodiment, although the measures against localized eddy current loss and heat generation due to concentration of eddy current i _e is subjected only to the lower core clamping bracket 202, the mounting table 212 by the winding 3U, 3V, the 3W If local eddy current loss and place the exotherm increases due to the concentration of the eddy current i _e by increasing the position in the height direction also occurs in the bracket 201 side with the upper core tightening, the lower core clamping fixture 202 You may make it perform the formation of the slit 207 which gave, and the chamfering process of the corner | angular part 206a to the applicable location of the upper iron core clamp 201. FIG.

  In the first embodiment, the iron core fastening device 2 for fastening the three-layered laminated core 1 has been described. However, the present invention relates to a two-legged laminated iron core or a three-legged or more laminated iron core. The present invention can also be applied to attachment devices.

  Moreover, although the laminated core 1 of the transformer has been described in the first embodiment, the core fastening device 2 according to the present invention is also applied to a stationary induction device such as a reactor including the laminated core 1 having the same configuration. Can do.

  As described above, the iron core fastening device 2 according to the present invention has an effect that local eddy current loss and heat generation in the lower iron core fastening fitting 202 can be prevented, such as a transformer and a reactor. This is useful as an iron core fastening device 2 for fastening a laminated iron core 1 of a stationary induction device.

A Transformer body 1 Laminated iron core 101 Upper yoke part 102 Lower yoke part 103U, 103V, 103W Leg 2 Iron core fastening device 201 Upper iron core fastening fitting 2011, 2012 Upper fastening plate 2011a Reinforcing piece 2013 Upper connecting member 2013a Fixed surface 202 Lower iron core clamps 2021, 2022 Lower clamp plate 2021a Reinforcing piece 2023 Lower connecting member 2023a Fixed surface 203 Connecting plate 204 Connecting member 205 Fixing member 205a Plate member 206 Base 206a Corner portion 207 Slit 208 Spacer 209 Fastener 209a Washer 209b Cylindrical cover 210 Base 211 Hook 212 Mounting base 212a Convex 213 Fastener 213a Bolt 213b Nut 214 Gap 3U, 3V, 3W Winding

Claims (10)

  In an iron core fastening device having a lower iron core fastening bracket for fastening a lower yoke part of a laminated iron core, a predetermined structure for inhibiting the concentration of the eddy current is provided at a location where the eddy current of the lower iron core fitting is concentrated. Iron core clamping device characterized by being provided. The lower core fastening metal fitting has a pedestal on which a winding wound around the leg is placed at a position corresponding to the leg of the laminated core.
The iron core fastening apparatus according to claim 1, wherein the predetermined structure is provided on the pedestal.   The iron core fastening device according to claim 2, wherein the predetermined structure is a structure in which a slit extending from an outer edge toward the leg portion is provided in the base.   The iron core fastening device according to claim 2, wherein the slit is provided on the entire seating surface so as to bisect the pedestal. An insulator is provided between the pedestal and the winding placed on the pedestal,
The iron core fastening device according to claim 3 or 4, wherein a protrusion that fits into a slit provided in the pedestal is formed on the insulator. The pedestal has a polygonal shape,
The core tightening device according to any one of claims 2 to 5, wherein the predetermined structure is a structure in which a corner portion of the pedestal is chamfered to form a curved surface at the corner portion. The lower iron core clamp includes a set of lower clamp plates that sandwich a lower yoke portion of the laminated core, a clamp that fastens the set of lower clamp plates that sandwich the laminated core, and the one set. Provided at both ends of the lower fastening plate of the set, including one set of connecting members for connecting one lower fastening plate and the other lower fastening plate,
The core tightening device according to claim 2, wherein the predetermined structure is a structure in which a gap is provided in a connection portion that connects the lower fastening plate and the connecting member.   The iron core fastening device according to claim 7, wherein the gap is further filled with an insulating member. A stationary induction device comprising a laminated iron core and a winding wound around a leg of the laminated iron core,
The said laminated iron core is clamp | tightened by the iron core clamping device as described in any one of Claims 1-7, The stationary induction apparatus characterized by the above-mentioned.   The static induction device according to claim 9, wherein the static induction device is a transformer.

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