JP2001060525A - Transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pole transformer which can be installed in a small space through reduction of the diameter of the tank of the transformer by increasing the occupation ration of an assembled parts to the tank. SOLUTION: A transformer is provided with an iron core/coil assembly, having an iron core 7 and a pair of coils 8 and a tank for housing the assembly. The tank bas a cylindrical shape. The coils 8 of the assembly adjoined to each other and the iron core 7 of the assembly has leg sections which are respectively passed through the windows of the coils 8. The coils 8 are formed to have D shapes, when the coils 8 are viewed from their end faces and the core 7 is constituted in the windows by combining magnetic plates, having different dimensions corresponding to the variation of the width sizes of the windows of the coils 8 with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer using a cylindrical tank, such as a pole transformer, and more particularly to a transformer suitable for installing a large-capacity pole transformer in a place where a mounting space is limited. It is about contents structure.

[0002]

2. Description of the Related Art The structure of a transformer using a conventional cylindrical tank will be described with reference to FIGS. This transformer is mainly used as a pole transformer. As shown in FIGS. 4 and 5, a conventional transformer includes an iron core 1, a coil 2, an upper clamp 3 ', a lower clamp 4', and a fixing bracket 5 'in a cylindrical tank 6'. The stored contents assembly (transformer body) is stored. 4 and 5, the lid of the tank 6 ', the connection terminal of the coil 2, the cooling medium (oil or insulating gas) in the tank 6' and the like are omitted. Also,
5A and 5B, the cross section of the tank 6 'is shown. The internal assembly is composed of a combination of a wound core 1 having a rectangular cross section and a coil 2 having a rectangular shape. As shown in FIG. 6, the structure of the wound core 1 is a steel plate 1b having a wide iron plate width.
Are disposed at the center of the iron core, and steel plates 1a and 1c having a narrower iron plate width are symmetrically stacked on both sides, and have a substantially rectangular cross section. The coil 2 is also rectangular according to its shape.
FIG. 6 is a cross-sectional view taken along the line AA ′ of FIG.

[0003]

When the contents of the transformer are put into the cylindrical tank 6 ', the diameter of the tank is set so that an appropriate insulation distance can be secured at the closest part between the contents charging part and the tank earth part. . In the case of the prior art, since the coil is rectangular, the finished shape of the transformer contents is approximated by a rectangle. Therefore, the diagonal position of the contents of the rectangular transformer is the closest part to the tank ground part, and the distance between the closest parts is the diagonal dimension of the approximated rectangle. Therefore, the tank diameter is a size obtained by adding an appropriate insulation distance to the approximate diagonal size of the rectangle. In general, the approximated rectangle often has a large ratio of the length of the short side to the long side (aspect ratio). Considering the circumscribed circle C2 that contacts the internal assembly, as shown in FIG. The space formed between the long side and the circumscribed circle is larger than the space formed between the short side and the circumscribed circle, and as a result, the occupancy of the transformer is reduced. In other words, if this structure is stored in a cylindrical tank, it requires more space than the contents assembly requires, and a large tank diameter is required despite the extra space inside the tank. Therefore, there is a problem that the miniaturization of the pole transformer is hindered.

[0004] It is an object of the present invention to provide a transformer in which the finished shape of an iron core / coil assembly is approximated to a circle so as to increase the occupancy of the contents of the tank and reduce the diameter of the tank.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention comprises an iron core / coil assembly having an iron core and a coil, and a tank for storing the iron core / coil assembly therein. A core / coil assembly has a pair of coils provided adjacent to each other and a core having a leg penetrating through a window of each of the pair of coils. It has a substantially D-shaped shape when viewed from the end face direction, and the iron core is characterized in that magnetic material plates having different widths are combined within the window of the coil in accordance with a change in the width of the window. is there.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. It is assumed that the transformer according to the present embodiment has the same rating and the same magnetic flux density as the transformer described in the above prior art. The transformer of the present embodiment is shown in FIG.
As shown in FIG. 2, an inner assembly (transformer main body) having a core 7, a coil 8, an upper clamp 3, a lower clamp 4, and a fixing bracket 5 is stored in a cylindrical tank 6. . 1 and 2, the illustration of the lid of the tank 6, the connection terminal of the coil 8, the cooling medium (oil or insulating gas) in the tank 6, and the like are omitted. 2A and 2B, the tank 6 is shown in cross section. Note that FIG.
It is a BB 'cross section of (a).

As shown in FIG. 1 or FIG. 3, the coil 8 of this embodiment has a D-shape or a trapezoidal shape as viewed from the end face thereof so as to improve the occupancy in the tank 6. It is formed. As shown in FIG. 3, when such a shape is used, the cross-sectional shape of the content assembly approaches a circle, and considering a circumscribed circle C1 in contact with the content assembly, a space created between the content assembly and the circumcircle C1 is considered. It can be kept almost constant, and as a result the occupancy of the content assembly increases. To improve the occupancy, it is desirable that the coil 8 has a D-shaped or semi-circular cross section. However, since the coil 8 is manufactured by winding a conductor on a former, it is actually formed at a corner. It is formed into a D shape or a trapezoidal shape with a curved portion formed. As a result, the coil 8 also has a D-shaped or trapezoidal window shape.

In this embodiment, the iron core 7 is formed by combining at least two types of magnetic plates having different widths in the window of the coil 8 so as to correspond to a change in the width of the window. As the magnetic plate, an electromagnetic steel plate such as a directional silicon steel plate is usually used, but the present invention is not limited to this, and an amorphous steel plate may be used to reduce iron loss under no load. As shown in FIG. 3, since the window shape of the coil 8 is a D shape or a trapezoidal shape, the iron core 7 has the widest magnetic plate on the inner peripheral side (inside the iron core window) of the wound iron core. The magnetic plates 7b, 7c, and 7d are wound around the outer periphery of the magnetic plates 7a, respectively, such that the width of the magnetic plates 7b, 7c, and 7d gradually decreases toward the outer peripheral side (outside the window) of the iron core. The cross section is formed so as to have a D shape or a trapezoid shape. The width and the number of stacked magnetic plates 7a, 7b, 7c, 7d are determined according to the size and shape of the window of the coil 8. Since it is not practical to prepare many types of widths of the magnetic plate in manufacturing the product, the D-shaped or trapezoidal shape is actually within the allowable range of the magnetic characteristics as shown in FIG. It is formed in a shape having a step.

A coil 8 is formed in the iron core 7 by a D-shaped linear portion or a trapezoidal lower portion (the length of the upper portion <the length of the lower portion).
Are mounted adjacent to each other, and the shape of the product in which the coil 8 is incorporated in the iron core 7 approaches a circle when viewed from the end face direction of the coil 8. As a result, the aspect ratio of the content assembly approaches 1, and the occupancy of the circumscribed circle C1 in contact therewith increases, so that the space can be effectively utilized. If the transformer has the same rating and the same magnetic flux density as the conventional transformer, the diameter of a circumscribed circle that contacts the internal assembly can be reduced. As a result, the diameter of the tank 6 to be stored can be reduced by about 10% as compared with the conventional one. Therefore, the present embodiment is effective for reducing the size of a device having a cylindrical tank such as a pole transformer. Further, in this embodiment, the upper fastener 3 and the lower fastener 4 have a substantially square planar shape as shown in FIG. 1, and the core 7 is attached to this axis in its axial direction (vertical direction in FIG. 1) and in a horizontal plane. It can be stably supported in any vertical direction (left-right direction in FIG. 1), and can improve the earthquake resistance. In addition, since the fixing bracket 5 can be shorter than the conventional one due to the decrease in the diameter of the tank 6,
Less material is required and weight can be reduced. Furthermore, according to the present embodiment, the amount of cooling oil can be reduced due to the miniaturization of the tank and the improvement of the occupancy, and the weight of the transformer can be reduced.

[0010]

According to the present invention, it is possible to reduce the tank diameter of a transformer having a cylindrical tank and obtain a transformer capable of saving space.

[Brief description of the drawings]

FIG. 1 is a plan view showing a storage state of a content assembly of a transformer in a tank according to an embodiment of the present invention.

FIGS. 2A and 2B are views showing a storage state of a content assembly of a transformer in a tank according to an embodiment of the present invention, wherein FIG.
(B) is a side view.

FIG. 3 is a plan cross-sectional view showing main parts of a coil and an iron core of a transformer according to one embodiment of the present invention.

FIG. 4 is a plan view showing a state in which a content assembly of a conventional transformer is stored in a tank.

5A and 5B are views showing a state in which the contents of a conventional transformer are stored in a tank, wherein FIG. 5A is a front view and FIG. 5B is a side view.

FIG. 6 is a cross-sectional plan view showing main parts of a coil and an iron core of a conventional transformer.

[Explanation of symbols]

3: Upper clamp, 4: Lower clamp, 5: Fixing bracket,
6: tank, 7: iron core, 8: coil.

Claims (4)

[Claims] An iron / coil assembly having an iron core and a coil, and a tank for storing the iron / coil assembly therein, wherein the tank has a cylindrical shape, and the iron / coil assembly is In a transformer having a pair of coils provided adjacent to each other and an iron core having legs penetrating through windows of the pair of coils, the coil has a substantially D-shape when viewed from the end face direction. A transformer, wherein the iron core is formed by combining magnetic plates having different widths in accordance with a change in the width of the window in the window of the coil. 2. The transformer according to claim 1, wherein the magnetic plate is an electromagnetic steel plate, and the iron core is formed by using at least two types of electromagnetic steel plates. 3. A structure in which the width of the magnetic plate is gradually reduced from the inside of the window of the coil to the outside of the window, so that the sectional shape of the iron core corresponds to the shape of the window of the coil. The transformer according to claim 1, wherein: 4. The iron / coil assembly, wherein the coil is D
2. The transformer according to claim 1, wherein the transformers are combined so that the linear portions of the character are adjacent to each other.