JP2008182053A - Resting induction electric appliance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resting induction electric appliance which prevents a local heat in a bolt portion when it is constituted by connecting a divided leg iron core fastening and intermediate iron core fastening integrally by a bolt, thereby reducing a loss drastically and enhancing a performance and a durability. <P>SOLUTION: An iron core is constituted of: at least two iron core legs 1 coiling a winding; an upper yoke 2 and lower yoke 3 coupling each iron core leg magnetically; and iron core fastenings 5, 6 disposed on both sides of each of the yokes 2, 3. Moreover, the lower yoke 3 is formed so as to be divided by an intermediate yoke connecting each leg yoke with these yokes, and the leg yoke is fastened and fixed by a leg iron core fastening 6A, and the intermediate yoke is fastened and fixed by an intermediate iron core fastening 6B, respectively. Also, the leg iron core fastening 6A is connected to the intermediate iron core fastening 6B integrally by the bolt. And, at a connection part of the leg iron core fastening 6A and the intermediate iron core fastening 6B, a short plate 20 of a nonmagnetic body having an electric resistance smaller than that of the iron core fastening is disposed to flow most of an eddy current. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a static induction electric device such as a transformer or a reactor, and more particularly to a static induction electric device using a split transport type iron core and an iron core clamp.

  Since static induction appliances such as transformers and reactors tend to increase in size as ultra-high voltage and capacity increase, transportation to the substation where they are installed is limited to transportation instead of conventional complete assembly transportation. In some places, contents assembly transportation and complete disassembly transportation are adopted as appropriate. For example, in the case of a transformer, the content body manufactured and dried at the factory is stored in the tank, and an insulating medium such as insulating oil or gas is sealed in the tank, and then various accessories are attached. After installation and production, it is completed by performing predetermined tests at the factory, but contents assembly transportation and complete disassembly transportation considering dimensions and weight restrictions are selected and applied in advance according to the installation location, and at the installation site It has been made possible to reassemble in a short time.

  In the assembly and transportation of the contents, only the transformer body itself is completely assembled and stored in the tank, and it is transported by enclosing an insulating gas such as oil immersion or nitrogen gas, and the removed attached parts are transported separately. Completely disassembled transportation is a means to disassemble properly so as to fall within the size and weight transportation restrictions including the transformer body itself, and transport in separate transportation tanks, both means designated by the local It is reassembled in a short period of time at the site and completed by field tests.

  In addition, for ultra-high voltage and large capacity transformers with severe transportation restrictions, the single-phase transformer is manufactured by dividing it into three or six single-phase cores using single-phase two-legged iron cores or single-phase three-legged iron cores. Three-phase transformers are also configured by combining the three-phase connections, but when the combination structure of single-phase transformers is a transportation problem, either content assembly or complete disassembly is used. Will do.

  When a single-phase transformer that is disassembled and transported and adopts a single-phase two-legged core composed of an iron core leg 1, an upper yoke 2 and a lower yoke 3 on which silicon steel plates are laminated as shown in FIG. After the primary side and secondary side windings 4 are wound on, the silicon steel plate to be the upper yoke 2 is inserted to constitute the contents main body. In the single-phase two-legged iron core having this structure, the lower yoke 3 is formed so as to be separable from the leg yoke 3A and the intermediate yoke 3B connecting the leg yokes 3A. And it has also been proposed to detach the upper yoke 2 and the intermediate yoke 3B so as to divide each core leg 1 around which the winding 4 is wound so as to be transported separately in a transport tank (for example, Patent Document 1).

  As shown in FIG. 7, this type of single-phase two-leg iron core is generally clamped with a bind band 7 made of an insulating material, and the upper yoke 2 and the lower yoke 3 each have a U-shaped cross section. The core fastening brackets 5 and 6 are formed in a shape and appropriately provided with reinforcing plates 8 and 9, and the core fastening brackets 5 and 6 on both sides are tightened with the connecting bolt 10 and the binding band 11 so as to be integrated. . The iron core clamp 6 is composed of a leg iron clamp 6A and an intermediate iron clamp 6B in accordance with the shape of the lower yoke 3 that can be divided, and a bolt (not shown) between them. Connected and mechanically integrated.

JP-A-11-3821

  However, in the above-described single-phase transformer that can divide the lower yoke, the winding wound around the iron core leg 1 as shown in FIG. When the leakage magnetic flux Φ1 from the intruder enters, an eddy current flows in a direction to cancel the leakage magnetic flux Φ1 as indicated by a solid line arrow. For this reason, the eddy current flows between the leg iron core clamp 6A and the intermediate iron core clamp 6B constituting the iron core clamp 6 through the bolts for mechanically connecting the two together, and for connecting In addition to causing local heating at the bolt portion, the loss increases, which is a big problem in terms of transformer performance and durability.

  Generally, non-magnetic shields made of a highly conductive material such as aluminum or copper that prevent leakage magnetic flux from entering are installed on the surfaces of the upper and lower iron core clamps. There is a possibility that the effect may not be sufficient with an iron core fastener made up of leg iron core fasteners and intermediate iron core fasteners.

  It is an object of the present invention to provide a connecting bolt when an iron core fastening bracket arranged on a lower yoke is constituted by integrally connecting a divided leg iron core fastening bracket and an intermediate iron core fastening bracket with a bolt. An object of the present invention is to provide a static induction electric appliance which can prevent local heating at a part and suppress loss, and can improve performance and durability.

  The static induction electric machine according to the present invention includes at least two iron core legs for winding a winding, upper and lower yokes that magnetically couple the iron core legs, and iron core clamps disposed on both sides of the yokes. An iron core is configured with a fitting, and the lower yoke is formed so as to be divided by each leg yoke and an intermediate yoke connecting them, and the leg yoke is formed by a leg iron core fastening bracket, In addition, the intermediate yoke is fastened and fixed by an intermediate core fastening bracket, and when the leg core fastening bracket and the intermediate core fastening bracket are integrally connected by a bolt, the leg core fastening bracket is used. In addition, a non-magnetic short-circuit plate having a lower electrical resistance than that of the iron core fastener is arranged at the connecting portion of the intermediate iron fastener.

  In addition, the short-circuit plate is disposed at a connection portion between the leg iron core clamp and the intermediate core clamp, and is connected and fixed by the bolt, and an eddy current flows between the short-circuit plates. It is characterized by the construction. In addition, the short-circuit plate is formed in a U-shaped cross-section by bending the non-magnetic plate, and the non-magnetic plate having the U-shaped cross-section is laterally connected to the connecting portion between the leg core fastening metal fitting and the intermediate iron core fastening metal fitting. It is characterized by being inserted and arranged and fixed.

  Further, the short-circuit plate is characterized in that it is arranged between the connecting portions of the leg iron core clamps and the intermediate iron core clamps, and is connected and fixed with connecting bolts.

  In the static induction appliance as in the present invention, a non-magnetic short-circuit plate having a lower electrical resistance than the iron core fastener is arranged at the connecting portion between the iron core fastener and the intermediate iron fastener. Most of the eddy current that flows so as to cancel out the magnetic flux leakage from the winding flows between the iron core clamp and the intermediate core clamp, which flows to the short-circuit plate. Can be greatly reduced, and the performance and durability can be improved.

  In the static induction electric machine of the present invention, at least two iron core legs that wind the windings, upper and lower yokes that magnetically connect between the iron core legs, and iron core clamps disposed on both sides of each yoke part. An iron core is composed of a metal fitting. In addition, the lower yoke is formed to be separable from each leg yoke and the intermediate yoke connecting them. The leg yoke is a leg core clamp, and the intermediate yoke is an intermediate core clamp. Each bracket is fastened and fixed, and the leg iron core clamp and the intermediate core clamp are integrally connected by bolts. A non-magnetic short-circuit plate having a smaller electrical resistance than that of the iron core fastener is arranged at the connecting portion between the leg iron iron fastener and the intermediate iron fastener.

  In the embodiment of FIGS. 1 and 2 showing a single-phase two-leg transformer to which the present invention is applied, the same parts as those in the prior art are denoted by the same reference numerals. The structure of the iron core on which the silicon steel plates of this example are laminated is also the same as the conventional two iron core legs 1 around which the winding is wound, and the upper yoke 2 and the lower yoke 3 that are magnetically coupled therebetween, It is comprised by the iron core fastening metal fittings 5 and 6 arrange | positioned on the both sides of each said yoke 2,3. In addition, considering the divided transportation of the transformer, the lower yoke 3 can be divided from the leg yoke and the intermediate yoke connecting them, respectively, and the leg iron core clamp 6A and the intermediate iron core clamp, respectively. The bracket 6B is fastened, and the leg iron core clamp 6A and the intermediate core clamp 6B are mechanically connected and integrated.

  The leg iron core fastening fitting 6A and the intermediate iron core fastening fitting 6B are integrally connected by a connecting bolt 21 that penetrates between the opposing end plates. At this time, the connecting portion of both the leg iron core clamp 6A and the intermediate iron core clamp 6B is made of a non-magnetic material such as a copper plate or an aluminum plate having a smaller electric resistance than the iron core clamp 6 according to the present invention. The short-circuit plate 20 is arranged as shown in FIG. Because of this structure, the short circuit plate 20 is vortexed in the direction to cancel the leakage flux Φ1 from the winding from one side to the other side of the leg iron core clamp 6A and the intermediate iron clamp 6B as indicated by the arrow. Most of the current flows.

  In the example of FIG. 2, the short-circuit plate 20 formed by bending a nonmagnetic plate into a U-shaped cross section is disposed on the side of the end plate positioned at the connecting portion between the leg iron core clamp 6A and the intermediate iron clamp 6B. Are inserted and arranged, and are connected and fixed by bolts 21. By making the short-circuit plate 20 into such a shape, the electrical connection between the short-circuit plates arranged on the side of the leg iron core fastening fitting 6A and the intermediate iron core fastening fitting 6B becomes unnecessary.

  The short-circuit plate 20 is separately manufactured from a non-magnetic material plate having a small electrical resistance such as copper or aluminum, and each is provided on each end plate surface of the connecting portion of the leg iron core fastening bracket 6A and the intermediate iron core fastening bracket 6B. They can be arranged and electrically connected using a connecting conductor so that most of the eddy current flows.

  The bolt 21 for mechanically connecting the leg core fastening bracket 6A and the intermediate core fastening bracket 6B mechanically integrally may be made of steel having high mechanical strength as in the conventional case, but in this case In order to prevent eddy current from flowing, an insulator is interposed in at least one of the connecting portions. Further, the bolt 21 may be made of an insulating material instead of using a steel one so that no eddy current flows.

  As described above, in the present invention, when the lower yoke 3 can be divided into the leg yoke and the intermediate yoke, the iron core is fastened to the connecting portion of the leg iron core fastening bracket 6A and the intermediate iron core fastening bracket 6B. Since the non-magnetic short-circuit plate 20 having a smaller electrical resistance than the metal fitting is arranged so that most of the eddy current flows, local heating in the bolt 21 is eliminated, so that loss can be greatly reduced, and performance and durability can be reduced. It becomes possible to further improve compared with the past.

  3 and 4 showing a single-phase two-leg transformer, which is another embodiment to which the present invention is applied, also in the embodiment, the same parts as in the prior art are similarly denoted by the same reference numerals. The structural feature of the single-phase two-leg transformer of this embodiment is that when the leg yoke and the intermediate yoke are connected and the lower yoke 3 is integrated, the leg portion constituting the iron core fastening bracket 6 is constructed. The iron core tightening bracket 6A and the intermediate iron core tightening bracket 6B are obtained by arranging a short-circuit plate 20 between end plates serving as a connecting portion and integrally connecting and fixing them with connecting bolts 21.

  Even in this structure, most of the eddy current flowing as shown by the arrows between the leg iron core clamps 6A and the intermediate iron core clamps 6B flows through the short-circuit plate 20, so that it is the same as in the above embodiment. In addition, the short-circuit plate 20 can be used as a dimension adjusting member between the leg iron core fastening fitting 6A and the intermediate iron core fastening fitting 6B by appropriately changing the plate thickness.

  In another embodiment shown in FIG. 5 of the present invention, the leg iron core clamp 6A and the intermediate iron core clamp 6B constituting the iron core clamp 6 are both insulated in the form of a hollow box. This is an example when a cooling medium passage 22 such as oil is provided. In this structure, since the cooling medium passage is also provided in each end plate that becomes the connecting portion between the leg iron core fastening fitting 6A and the intermediate iron core fastening fitting 6B, the hollow portion is formed so as not to close the cooling medium passage 22. The formed short-circuit plate 20 is arranged so as not to impair the cooling efficiency, and is integrally connected and fixed by a plurality of connecting bolts 21 arranged around the cooling medium passage portion, and most of the eddy current is supplied to the short-circuit plate 20. I try to make it flow.

  When the cooling medium passage 22 is provided in the iron core tightening bracket 6 of the lower yoke 3, a leg iron core tightening bracket 6A and an intermediate iron core tightening bracket 6B having a U-shaped cross section are used to connect the two together. Then, the short-circuit plate 20 can be attached and configured. In this case, the short-circuit plate 20 is inserted and arranged from the side of the end plate as shown in FIG. 2, and is connected and fixed by the bolts 21, or the short-circuit plate 20 is connected between the end plates serving as the connection portions as shown in FIG. It is possible to apply a structure that is arranged and integrally connected and fixed by the connecting bolt 21 and can achieve the same effect.

  In each of the above-described embodiments, the present invention has been described with reference to an example in which the present invention is applied to a single-phase two-leg transformer, but also to a three-phase transformer using a three-phase three-leg iron core or a three-phase five-leg iron core, and further to a reactor. Obviously, it can be applied, and in this case a similar effect can be achieved.

It is a schematic front view which shows the iron core structure of the single phase 2 leg transformer which is one Example of this invention. It is a perspective view which shows the principal part of FIG. It is a schematic front view which shows the iron core structure of the single phase 2 leg transformer which is the other Example of this invention. It is a perspective view which shows the principal part of FIG. It is a perspective view which shows the principal part which is another Example of this invention. It is a schematic front view which shows the iron core structure of the conventional single phase 2 leg transformer. It is a schematic front view which shows the content main-body part of the conventional single phase 2 leg transformer.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Iron core leg, 2 ... Upper yoke, 3 ... Lower yoke, 5, 6 ... Iron core clamp, 6A ... Leg core clamp, 6B ... Intermediate core clamp, 20 ... Short-circuit plate, 21 ... bolt.

Claims (4)

  An iron core is constituted by at least two iron core legs that wind the windings, upper and lower yokes that magnetically couple each of the iron core legs, and iron core fasteners that are disposed on both sides of each of the yokes. The lower yoke is formed so as to be divided by each leg yoke and an intermediate yoke connecting the leg yokes. The leg yoke and the intermediate yoke are formed of a leg iron core clamp and an intermediate iron core clamp. In the stationary induction device that is fixed by fastening with the brackets, and the leg iron core clamp and the intermediate core clamp are integrally connected by bolts, the leg core clamp and the intermediate core clamp A stationary induction device characterized in that a non-magnetic short-circuit plate having an electric resistance smaller than that of the iron core fastening fitting is arranged in the connecting portion.   In Claim 1, the said short circuit board is each arrange | positioned in the connection part of the said leg part iron core clamp | fastening metal fitting, and an intermediate | middle iron core clamp metal fitting, and while connecting and fixing with the said volt | bolt, an eddy current is produced between the said both short circuit boards. A static induction machine characterized by being configured to flow.   3. The short-circuit plate according to claim 2, wherein the short-circuit plate is formed by bending a non-magnetic plate into a U-shaped cross section, and the non-magnetic plate having the U-shaped cross-section is connected to the connecting portion between the leg core fastening metal fitting and the intermediate iron core fastening metal fitting. A stationary induction device characterized in that it is inserted and arranged from the side and fixedly connected.   The stationary induction device according to claim 1, wherein the short-circuit plate is arranged and connected and fixed between the connecting portions of the leg iron core clamps and the intermediate iron core clamps.

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