JP2015220349A - Stationary induction electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stationary induction electric machine which achieves weight reduction and downsizing.SOLUTION: A stationary induction electric machine 10 includes: a tank 11; an iron core 12; and a coil 13. The tank includes a cylindrical inner surface. The iron core has iron core leg parts and is housed in the tank so that a direction of an axis of each iron core leg part is set to a direction perpendicular to the cylindrical inner surface of the tank. The coil is wound around the iron core leg parts and made of aluminium.

Description

  Embodiments of the present invention relate to a static induction machine having at least a stationary iron core and windings.

  Static induction machines include transformers and reactors. Each of them has at least a stationary iron core and windings. In a transformer, there are two or more windings such as a primary winding and a secondary winding. In a reactor, there is usually one winding. . Static induction appliances are common appliances in substations and power plants, and their electrical ratings are increasing in capacity. On the other hand, in recent years, demands for weight reduction and downsizing have been intensified so as to ease the conditions for transporting and installing static induction appliances.

The weight and volume of the static induction machine are related not only to the weight and volume of the iron core and winding, but also to the weight and volume of a tank that is a container for accommodating these. The tank is filled with an insulator (insulating oil or insulating gas), and the insulation as an electric appliance is greatly enhanced. In recent years, due to environmental considerations, there has been an increasing demand for gas-insulated static induction appliances in which an insulating gas such as SF ₆ gas is enclosed as an insulator that is easier to manage.

  In order to reduce the size and weight of static induction devices, it is possible to reduce the size of the tank on the premise of ensuring insulation, and to reduce the material of each member of the static induction device including the tank. It is done. However, it is the first condition that mechanical strength is ensured in each part, and there is a certain difficulty in reducing the weight and size so as to satisfy both.

JP 2008-41929 A

  The problem to be solved by the present invention is to provide a static induction device that can be reduced in weight and size.

  The static induction electric machine of embodiment has a tank, an iron core, and a coil | winding. The tank has a cylindrical inner surface. The iron core has iron core legs, and is accommodated in the tank so that the axis direction of the iron core legs is perpendicular to the cylindrical inner surface of the tank. The winding is wound around the iron core leg and is made of aluminum.

The front view which shows the structure of the transformer which is the stationary induction | guidance | derivation induction machine of Embodiment 1-3. The side view which shows the structure of the transformer which is a stationary induction | guidance | derivation electric appliance of Embodiment 1 thru | or 3. Sectional drawing of the arrow direction in the A-Aa position shown in FIG. Sectional drawing of the arrow direction in the B-Ba position shown in FIG.

(Embodiment 1)
Based on the above, hereinafter, the static dielectric of the embodiment will be described with reference to the drawings. FIG. 1 shows the static dielectric of the first embodiment. More specifically, FIG. 1 is a front view of a transformer which is one aspect of the static induction electric device. FIG. 2 is a side view of the same transformer. As shown in FIGS. 1 and 2, the transformer 10 includes a tank 11, an iron core 12, and a winding 13.

The tank 11 is a container that houses the iron core 12 and the winding 13. The tank 11 is filled with, for example, an insulating gas (SF ₆ ) in order to maintain high insulation during operation. The iron core 12 has an iron core leg portion 12a and a yoke portion (yoke) 12b. A winding 13 is wound around the iron core leg portion 12a, and the iron core leg portion 12a and the adjacent iron core leg portion 12a Are connected to both ends of the iron core leg portion 12a by the yoke portion 12b. That is, the iron core 12 is configured such that the magnetic flux generated by the winding 13 flows through the magnetic path formed by the iron core leg portion 12a and the yoke portion 12b.

  The transformer 10 includes three core leg portions 12a, and the number of windings 13 is three, which is the same as the number of core leg portions 12a. This is because it is configured as a three-phase AC transformer. As will be described later, each of the windings 13 has an inner winding (secondary side) and an outer winding (primary side). The three inner windings are Y-connected or Δ-connected. Similarly, the three outer windings are Y-connected or Δ-connected. An electrical terminal as the transformer 10 is provided so as to be exposed to the outside of the tank 11 (not shown).

  As shown in the drawing, the tank 11 has a horizontally long cylindrical shape, and both ends of the horizontally long are in the shape of a lid and are removable. One of the horizontally long ends is removed, a structure having the iron core 12 and the winding 13 is introduced into the tank 11 and a lid is fixed to the end, and the structure shown in FIG. The structure including the iron core 12 and the winding wire 13 is in a posture suitable for being introduced into the tank 11 (in the drawing, the axis of the iron core leg portion 12a is in the vertical direction).

  3 is a cross-sectional view in the direction of the arrow at the A-Aa position shown in FIG. 4 is a cross-sectional view in the direction of the arrow at the position B-Ba shown in FIG. 3 and 4, the same components as those already shown in FIGS. 1 and 2 are denoted by the same reference numerals. Hereinafter, the configuration of the transformer 10 will be further described with reference to FIGS. 3 and 4.

  As shown in FIG. 3, the inner surface of the tank 11 has a cylindrical shape similar to the appearance of the tank 11. Since the tank 11 has a shape having a cylindrical inner surface, the stress is easily made uniform mechanically. For example, the thickness can be relatively reduced with respect to the stress caused by the enclosed insulating gas, and the weight can be reduced. is there. Further, not only the pressure of the sealed insulating gas but also the process of sealing the insulating gas, the air inside the tank 11 is once evacuated to a state close to vacuum, so that it is suitable for the shape of the stress generated in that case. ing. And since it is cylindrical, a specific weak part does not produce easily and possibility that a reinforcement member is required is small. Therefore, the weight can be reduced by eliminating the need for a reinforcing member.

  The iron core 12 is accommodated in the tank 11 so that the direction of the axis of the iron core leg portion 12 a is perpendicular to the cylindrical inner surface of the tank 11. Accordingly, the position of the iron core 12 is not biased, and the diameter of the tank 11 can be set according to the total length of the iron core leg portion 12a as viewed in the axial direction, and the tank 11 can be miniaturized.

  Further, the roundness of the inner surface of the tank 11 secures a relatively large distance from the winding 13 wound around the iron core leg portion 12a to the inner surface of the tank 11, as shown in FIG. Therefore, using this distance, an aluminum material is used for the outer winding 13a. In general, aluminum has a lower mechanical strength than copper, and has a higher electrical resistivity. Therefore, in order to obtain the same mechanical strength and conductivity as a copper wire, it is necessary to use a wire having a large cross-sectional area. Volume increases. However, since the distance is secured as described above, it is possible in the tank 11 to cope with an increase in volume of the winding portion due to the use of aluminum. Therefore, the transformer 10 can be greatly reduced in weight by using the outer winding 13a made of aluminum.

  In this embodiment, as described above, the outer winding 13a is made of an aluminum material, while the inner winding 13b is made of a copper material. The reason why the materials are different depending on the windings is as follows. Generally, a buckling stress is generated in the inner winding 13b in accordance with a force in a direction in which the winding diameter of the winding is reduced by a magnetic field and an electric current, and conversely, in the direction in which the winding diameter of the winding is increased. A tensile stress is generated to respond to the force. The strength against buckling and the strength against tension are generally greater in strength against tension. Therefore, the use of aluminum having relatively poor mechanical strength is limited to the outer winding 13a, and the role for stress is shared.

  As shown in FIGS. 3 and 4, the aspect in which the outer winding 13 a is wound with a larger number of turns than the inner winding 13 b in the iron core leg portion 12 a is a general aspect of a transformer. . As a general possibility of the transformer, the number of turns is not particularly limited between the inner winding and the outer winding.

  As described above, according to the stationary induction device of the first embodiment, first, since the tank 11 has a shape having a cylindrical inner surface, the stress is easily equalized mechanically, and the insulating gas is sealed. The wall thickness can be relatively reduced with respect to the generated stress, and the weight can be reduced. In addition, since the iron core 12 is accommodated in the tank 11 so that the axis direction of the iron core leg portion 12a is perpendicular to the cylindrical inner surface of the tank 11, the total length of the iron core leg portion 12a in the axial direction. The diameter of the tank 11 can be set according to the size of the tank 11, and the tank 11 can be miniaturized.

  Further, due to the roundness of the inner surface of the tank 11, a relatively large distance is secured from the winding 13 wound around the iron core leg portion 12 a to the inner surface of the tank 11. Therefore, using this distance, an aluminum material is used for the outer winding 13a. The use of the aluminum winding 13a can greatly reduce the weight of the transformer.

(Embodiment 2)
Next, the transformer according to the second embodiment will be described with reference to the drawings already described. The tank 11 can employ a non-magnetic steel material in addition to using a general iron-based alloy for the material. By using a non-magnetic steel material as the material of the tank 11, it is possible to greatly reduce the rate at which the leakage magnetic flux originating from the windings 13 and the iron core 12 permeates the tank 11. Thus, local overheating of the tank 11 due to leakage magnetic flux can be prevented without particularly adding a shield member or the like. Therefore, it can contribute to further weight reduction in that a shield member is unnecessary.

  In particular, an aluminum material is easy to adopt as the tank 11 in terms of availability, workability, and cost. Aluminum is an example of a non-magnetic steel material. However, since the density is much lower than that of an iron-based alloy, if the tank 11 is made of an aluminum material, the weight can be further reduced as a transformer. In addition to light weight, it is conceivable to use an alloy mainly containing aluminum.

(Embodiment 3)
Next, the transformer according to the third embodiment will be described with reference to the drawings already described. As described above, the inner winding 13b can be made of an aluminum material in the same manner as the outer winding 13a, in addition to using a copper material. As already mentioned, generally, a buckling stress is generated in the inner winding 13b by the magnetic field and current so as to reduce the winding diameter of the winding, and the buckling stress is generally weaker than the tensile stress in general.

  However, as long as the buckling stress generated in the inner winding 13b allows, an aluminum material wire can be used as the inner winding 13b. When aluminum is used, generally, the cross-sectional area becomes thicker and the volume increases as a winding, but the inner surface of the tank 11 is cylindrical, and a sufficient space is secured between the winding 13 and the inner surface. Therefore, such a configuration can be established.

  Also in such a case, it can be assumed that the outer winding 13a is wound with a larger number of turns than the inner winding 13b in the iron core leg portion 12a. Such an aspect is a general aspect as a transformer. As a general possibility of the transformer, the number of turns is not particularly limited between the inner winding and the outer winding.

(Other embodiments)
In the transformer described above, the structure in which the insulating gas is sealed is shown. However, in the structure in which the insulating oil is stored in the tank 11 and the iron core 12 and the winding 13 are immersed in the insulating oil. As a transformer, the effect of reducing the weight and size as described above can be obtained. In general, insulating gas is easier to handle than liquids such as insulating oil. In any case, discharging into the environment is not preferable in terms of environmental load, but in the case of gas, the discharge can be managed by controlling the gas pressure and temperature. In the case of liquid, even if liquid leakage occurs, the operation as a transformer is not affected at first, and management is not as easy as gas.

  Moreover, although the transformer demonstrated above was a three-phase transformer, even if it is a case of a single phase transformer, the effect of light weight miniaturization which was naturally demonstrated is acquired. Furthermore, even if it is not a transformer but a reactor, the light weight reduction effect as described naturally can be obtained.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Static induction machine (transformer), 11 ... Tank, 12 ... Iron core, 12a ... Iron core leg part, 12b ... Relay part (yoke), 13 ... Winding (winding part), 13a ... Outer winding, 13b ... inner winding.

Claims (8)

A tank having a cylindrical inner surface;
An iron core housed in the tank, having an iron core leg so that the direction of the axis of the iron core leg is perpendicular to the cylindrical inner surface of the tank;
A static induction electric machine comprising: an aluminum winding wound around the iron core leg. A second winding which is a copper winding wound around the iron core leg,
The static induction machine according to claim 1, wherein in the iron core leg portion, the second winding is wound as an inner winding and the winding is wound as an outer winding. The stationary state according to claim 2, wherein in the iron core leg portion, the second winding is wound as an inner winding, and the winding is wound as an outer winding with a larger number of turns than the second winding. Induction machine.   The static induction machine according to claim 1, wherein the tank is made of a non-magnetic steel material.   The static induction machine according to claim 4, wherein the tank is made of an aluminum material. A second winding which is an aluminum winding wound around the iron core leg,
The static induction machine according to claim 1, wherein in the iron core leg portion, the second winding is wound as an inner winding and the winding is wound as an outer winding. The stationary state according to claim 6, wherein in the iron core leg portion, the second winding is wound as an inner winding, and the winding is wound as an outer winding with a larger number of turns than the second winding. Induction machine.   The stationary induction device according to claim 1, further comprising an insulating gas sealed in the tank.

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