JP2002359124A - Dry transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dry transformer that can save energy and resources, and is friendly to environment by improving heat radiation efficiency. SOLUTION: A coil support spacer is arranged among a core 1 and low- and high-pressure coils 2 and 3 for supporting the low- and high-pressure coils 2 and 3 by the core, and at the same time a vertical upper portion in space being formed by the low-pressure coil 2 and core 1 is opened in an upper fixture 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry transformer for distributing electric power.

[0002]

2. Description of the Related Art Conventionally, as a supporting structure of a dry type transformer and a metal fitting shape, Japanese Patent Application Laid-Open Nos.
What is described in -17282837 is known.

FIGS. 17 and 18 show a conventional dry-type transformer supporting structure and metal fittings, including a low-voltage coil 32 and a high-voltage coil 33, and an iron core 31 inserted into the low-voltage coil 32 and the high-voltage coil 33. An upper clamp 34 or an upper clamp 36 for sandwiching the iron core 31 with the low-voltage coil 32 and the high-voltage coil 33, a lower clamp 35 or a lower clamp 37,
This is a structure in which a coil receiver 38 that supports the low-voltage coil 32 and the high-voltage coil 33 is combined.

The upper clamp 34 has an L-shape, and the upper clamp 36 has a U-shape.

[0005]

In the above-mentioned conventional dry type transformer, in order to facilitate the processing of the upper clamp 34 or the upper clamp 36, the upper clamp 34 and the upper clamp 36 are formed by bending an iron plate. The shape was L-shaped or U-shaped. Therefore, the upper clamp 34 or the upper clamp 36 is
The structure has a structure in which the space vertically between the iron core 31 and the low-voltage coil 32 is closed vertically, and the resistance to air flowing upward from between the iron core 31 and the low-voltage coil 32 during heat radiation increases, resulting in poor heat radiation efficiency.

Further, since the core 31 and the lower clamp 35 or the lower clamp 37 are in contact with each other, the core 3 is not operated when the transformer is operated.
The vibration generated from the iron core 31 due to the magnetostrictive vibration of the electromagnetic steel plate (not shown) constituting the lower clamp 1 or the lower clamp 3 or 3
7, the noise generated by the iron core 31 is added to the secondary noise generated by the lower fastener 35 or the like, and the noise of the entire transformer is increased. The iron core 31 and the lower clamp 35 or the lower clamp 37
Although there is a transformer in which rubber (not shown) is arranged between them, the vibration cannot be completely shut off because the iron core 31 and the lower clamp 35 or the lower clamp 37 are physically connected. Further, when the iron core 31 and the lower fastener 35 or the lower fastener 37 are in contact with each other via the rubber, stress is applied to the iron core 31,
When stress is applied to the iron core 31, distortion occurs in the magnetic steel sheet constituting the iron core 31, and the magnetic properties of the magnetic steel sheet are deteriorated and noise increases.

[0007]

In order to achieve the above object, a first means of the present invention comprises an iron core, a low-voltage coil disposed outside the iron core, and a high-voltage coil disposed outside the low-voltage coil. A coil support spacer disposed between upper and lower end surfaces of the low-voltage coil and the high-voltage coil and upper and lower yoke portions of the iron core, the low-voltage coil and the high-voltage coil are supported by the iron core, In this structure, a vertically upper portion of a gap formed by a coil and an iron core is opened.

[0008] The second means of the present invention includes an iron core, a low-voltage coil disposed outside the iron core, a high-voltage coil disposed outside the low-voltage coil, an upper fitting and a lower fitting,
An upper coil support spacer disposed between the upper end surface of the low-voltage coil and the high-voltage coil and the upper yoke of the iron core, and a lower coil support spacer disposed between the lower end surface of the low-voltage coil and the high-voltage coil and the lower bracket, The lower coil supporting spacer is in contact with the lower metal fitting and the low voltage coil and the lower metal fitting located in the window of the iron core, and does not block the lower end of the high voltage coil.

According to a third aspect of the present invention, in the second aspect, the upper bracket has a structure in which a vertically upper portion of a gap formed by a low-voltage coil and an iron core is opened.

According to a fourth aspect of the present invention, a lower coil supporting spacer supports a low voltage coil and a high voltage coil,
The iron core is supported by the upper coil support spacer, and the bottom surface of the iron core and the lower bracket have a gap without being in contact with each other.

According to a fifth aspect of the present invention, in addition to any one of the first to fourth aspects, the upper coil supporting spacer has a projection in the direction of the low-voltage coil and the high-voltage coil.
At least a part of the projection is cut obliquely.

According to a sixth aspect of the present invention, in addition to any one of the second to fourth means, the lower coil supporting spacer has a length capable of supporting all the low-voltage coils and the high-voltage coils, and , The low-voltage coil and the high-voltage coil have pores in the radial direction.

According to a seventh aspect of the present invention, in addition to any one of the second to fourth means, the lower coil supporting spacer has a length capable of supporting all the low-voltage coils and the high-voltage coils, and At least a portion in contact with the low-voltage coil and the high-voltage coil is a material having a buffering property, and a cutout is provided in the buffer material portion.

According to an eighth aspect of the present invention, in addition to any one of the second to fourth means, the lower coil supporting spacer has a length capable of supporting all the low-voltage coils and the high-voltage coils, and At least a portion in contact with the low-voltage coil and the high-voltage coil is a material having a buffering property, and the buffer portion is a rod-shaped aggregate having a density of 80% or more.

[0015]

According to the first aspect of the present invention, according to the dry transformer, the generated heat is radiated from the surface of the iron core or the surface of the coil to warm the surrounding air. The air that has moved upward from between the low-voltage coil and between the low-voltage coil and high-voltage coil, and has moved upward from between the iron core and the low-voltage coil, must have the vertical upper part of the gap between the low-voltage coil and the iron core open. As a result, the upper metal member having a structure having a small flow path resistance to air is reached, and further, efficiently moves into the upper atmosphere through the upper metal member having a small flow path resistance to release heat.

According to the second aspect of the present invention, the generated heat is radiated from the surface of the iron core or the surface of the coil to warm the surrounding air, and the heated air flows between the iron core and the low-voltage coil or between the iron core and the low-voltage coil. The heat moves upward from between the high-voltage coils and radiates heat, and air flows into the moved portion from below the coil including the lower end of the coil located in the window of the iron core.

According to the third aspect of the present invention, the generated heat is radiated from the surface of the iron core or the surface of the coil to warm the surrounding air, and the heated air flows between the iron core and the low-voltage coil or between the iron core and the low-voltage coil. The heat moves upward from between the high-voltage coils and emits heat, and air flows in from the lower part of the coil including the lower end of the coil located in the window of the iron core into the moved part, and further, the flow path resistance is low. Efficiently moves through the upper fitting into the upper atmosphere and releases heat.

According to the fourth aspect of the present invention, the stress of the iron core is alleviated, and the transmission of the magnetostrictive vibration to the metal fittings and the like is suppressed.

According to the fifth aspect of the present invention, the coil is supported in the vertical direction, the distance between the iron core and the low-voltage coil, and the distance between the low-voltage coil and the high voltage and the coil are defined. When the transformer dissipates heat, the air rising upward from the coil reaches the upper coil support spacer and the protrusion is cut obliquely, so the flow path resistance is reduced. Reduced.

According to the sixth means of the present invention, in addition to any one of the second means to the fourth means, when the coil is moved by the electromagnetic mechanical force at the time of the short-circuit test of the transformer, the lower coil is attached to the end face of the coil. Reduces the risk of hitting the corners of the support spacer and damaging the coil, and provides stable coil support.The lower coil support spacer has pores in the radial direction of the coil to reduce flow path resistance, and when cooling the transformer The air passing through the pores of the lower coil support spacer enters between the coils from below the coils and cools the iron core and the coil surface.

According to the seventh aspect of the present invention, when a force for supporting the coil in the vertical direction is applied, the rubber is made uneven, and the rubber is supported vertically by the concave portion and the horizontal coil interval is maintained by the protrusion. And realizes stable coil support.

According to the eighth means of the present invention, when a force for supporting the coil in the vertical direction is applied, the rubber is made uneven, and the rubber is supported in the vertical direction by the concave portion and the horizontal coil interval is maintained by the protrusion. In addition, since the rubber rod-shaped aggregate is used, air can flow between them, thereby improving the heat radiation efficiency.

(Embodiment 1) FIGS. 1, 2 and 3 are schematic perspective views of a three-phase molded wound core transformer according to a first embodiment of the present invention, and top schematic views of a three-phase molded wound core transformer. 1 shows a schematic side sectional view of a molded core transformer.

1, 2 and 3, 1 is an iron core, 2
Is a low voltage coil located outside the iron core 1, 3 is a high voltage coil located outside the low voltage coil 2, 4 is a bracket, 5 is a bracket 4
And an upper bracket having a structure in which a vertically upper portion of a gap formed by the low-voltage coil 2 and the iron core 1 is opened, 6 is a lower bracket that forms the metal fitting 4, 8 is an upper end face of the low-voltage coil 2 and the high-voltage coil 3 and an iron core. An upper coil supporting spacer, which is disposed between the upper yoke of the first core and a width smaller than the width of the core, is a lower coil disposed between the lower end surfaces of the low voltage coil and the high voltage coil and the lower yoke of the core. The support spacer 10 is a gap between the iron core 1 and the low-voltage coil 2. Although not shown, the iron core 1
A spacer made of an insulating material is provided between the low-voltage coil 2 and the low-voltage coil 2 and between the low-voltage coil 2 and the low-voltage coil 2. These spaces are provided with spaces that do not affect characteristics such as insulation. .

The operation of the three-phase wound core mold transformer (hereinafter referred to as a transformer) configured as described above will be described. When the transformer operates, the core loss caused by the iron core 1 and the low-voltage coil 2 and the high-voltage coil 3 (hereinafter, referred to as a coil 41).
As a result, heat is generated by a loss such as copper loss, and the heat increases the temperature of the coil. The generated heat is radiated from the surface of the iron core 1 and the surface of the coil 41 to warm the surrounding air, and the heated air flows upward from between the iron core 1 and the low-voltage coil 2 or from between the low-voltage coil 2 and the high-voltage coil 3. Go to The air that has moved upward from between the iron core 1 and the low-voltage coil 2 is transferred to the upper metal fitting 5 having a structure with little resistance to air because the vertically upper part of the gap formed by the low-voltage coil 2 and the iron core 1 is open. Then, the air moves efficiently into the upper atmosphere through the upper metal fitting 5 having little resistance to the air to release heat.

The temperature rise limit of the winding conductor portion of the molded transformer must be 95 K or less, which is the limit determined by JIS C 4306, and the temperature rise of the coil 41 depends on the heat generation amount of the iron core 1 and the coil 41 and the coil. 41 is determined by the relationship with the surface area of 41 and the metal fitting structure of the transformer. Therefore, with respect to the temperature characteristics of the transformer, it is important to improve the heat radiation efficiency by the metal fitting structure or the like.

As described above, the coil supporting spacer is disposed between the iron core 1 and the coil 41 to support the coil 41 with the iron core 1, and the upper metal fitting 5 is disposed vertically above the gap formed by the low-voltage coil 2 and the iron core 1. With the open structure, the resistance of the air heated by the heat generated by the iron core 1 and the coil 41 to flow upward is reduced, and the high-pressure coil is located inside the high-voltage coil 3 and has a smaller surface area than the high-voltage coil 3. 3, the heat radiation efficiency of the low-voltage coil 2, which is more difficult to dissipate, can be improved, and the temperature rise of the winding can be reduced by about 3%. By improving the heat radiation efficiency, the temperature rise of the coil 41 can be suppressed, the resistance increase due to the temperature rise of the conductor in the coil 41 can be suppressed, and energy saving of the device can be realized. In addition, by designing the equipment so as to increase the heat radiation efficiency and to reduce the cross-sectional area of the conductor constituting the coil 41 in consideration of the heat radiation efficiency improvement so as to have a temperature rise value near the temperature rise limit. In addition, the size and weight of the device can be reduced, and the amount of materials used for manufacturing the device can be reduced, thereby realizing resource saving.

(Embodiment 2) FIGS. 4, 5, and 6 are schematic perspective views of a three-phase molded cored transformer according to a second embodiment of the present invention.
FIG. 2 shows a schematic cross-sectional view of a part of a phase winding core mold transformer.

Referring to FIG. 4, FIG. 5, and FIG.
1, 2, and 3 are denoted by the same reference numerals, detailed description thereof will be omitted, and different portions will be mainly described. Reference numeral 11 denotes a U-shaped upper metal fitting, 12 denotes a concave-shaped lower metal fitting, and 13 denotes a lower coil supporting spacer arranged between the lower end faces of the low-voltage coil 2 and the high-voltage coil 3 and the lower metal fitting 12. 1, 2, and 3 is that the upper metal fitting 11 has a structure in which the vertically upper part of the gap formed by the low-voltage coil 2 and the iron core 1 is not open, and the lower metal fitting 6 is replaced by a concave shape. The lower metal fitting 12 is provided, and the lower coil supporting spacer 13 which does not block the lower end of the coil 41 located in the window of the iron core 1 is disposed between the lower metal fitting 12 and the coil 41 to support the coil 41. is there.

The operation of the transformer configured as described above will be described. When the transformer operates, heat is generated due to iron loss due to the iron core 1 and loss due to the coil 41, and the heat causes the temperature of the coil 41 to rise. The generated heat is radiated from the surface of the iron core 1 and the surface of the coil 41 to warm the surrounding air, and the heated air flows upward from between the iron core 1 and the low-voltage coil 2 or from between the low-voltage coil 2 and the high-voltage coil 3. To release heat, and air flows into the moved portion from below the coil 41 including the lower end of the coil 41 located in the window of the iron core 1. This cycle causes the transformer to release heat.

As described above, the upper coil supporting spacer 8 having a width smaller than the width of the iron core 1 is disposed between the upper end surface of the coil 41 and the upper yoke of the iron core 1, and the concave lower metal fitting 12 and the coil 41 are arranged. The lower coil supporting spacer 13 which does not block the lower end of the coil 41 located in the window of the iron core 1 is disposed between the lower coil supporting spacers 13 to support the coil 41. The inflow of air for carrying heat can be made more efficient, and the temperature rise of the winding can be reduced by about 2%. By improving the heat radiation efficiency, the temperature rise of the coil 41 can be suppressed, the resistance increase due to the temperature rise of the conductor in the coil 41 can be suppressed, and energy saving of the device can be realized. In addition, by designing the equipment so as to increase the heat radiation efficiency and to reduce the cross-sectional area of the conductor constituting the coil 41 in consideration of the heat radiation efficiency improvement so as to have a temperature rise value near the temperature rise limit. In addition, the size and weight of the device can be reduced, and the amount of materials used for manufacturing the device can be reduced, thereby realizing resource saving.

The smaller the width of the upper coil supporting spacer 8 disposed between the upper end surface of the coil 41 and the upper yoke of the iron core 1, the smaller the resistance to the air that radiates heat and the better the heat radiation efficiency. The width of the upper coil supporting spacer 8 only needs to have a supporting area that can withstand the short-circuit strength during the short-circuit test of the transformer.

In the second embodiment, the upper fitting 11
As the upper metal fitting 5 of the first embodiment, not only the efficiency of the air inflow side but also the efficiency of the outflow side can be improved, and the synergistic effects thereof are larger than the effects of the first and second embodiments. The effect can be realized, and the temperature rise of the winding can be reduced by about 5%.

(Embodiment 3) FIG. 7 is a schematic cross-sectional side view of a three-phase molded cored transformer according to Embodiment 3 of the present invention.

In FIG. 7, parts having the same structure and operation as those in FIGS. 4, 5, and 6 of the second embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different parts will be mainly described. I do. Reference numeral 14 denotes a gap between the bottom surface of the iron core 1 and the lower metal fitting 12. 4, 5, and 6 of the second embodiment is different in that the lower metal fitting 12 and the lower coil supporting spacer 9 disposed between the lower end surface of the coil 41 and the lower metal fitting 12 support the coil 41. At the same time, the core 1 is supported by the coil 41 and the upper coil supporting spacer 8 disposed between the upper end surface of the coil 41 and the upper yoke of the core, and there is a gap without the bottom surface of the core 1 and the lower metal fitting 12 being in contact with each other. That is the point.

The operation of the above-structured transformer will be described. When the transformer is energized, magnetic flux passes through the inside of the iron core 1, and this magnetic flux causes magnetostriction, which is expansion and contraction of the electromagnetic steel sheet constituting the iron core 1, and generates vibration and noise. Here, it is generally known that the iron core 1 made of an electromagnetic steel sheet tends to increase noise when subjected to stress by being in contact with metal fittings or the like. When the iron core 1 is in contact with metal fittings, vibration due to the magnetostriction of the iron core 1 is transmitted to the metal fittings and the like, and the metal fittings and the like serve as a secondary noise generation source. To increase.

As described above, the lower bracket 12 and the coil 4
The coil 41 is supported by the lower coil support spacer 9 disposed between the lower end surface of the first coil 1 and the lower metal fitting 12, and the upper coil support spacer 8 disposed between the upper end surface of the coil 41 and the upper yoke of the iron core. As a result, the core 1 is supported, and the bottom surface of the iron core 1 and the lower bracket 12 have a gap 14 without being in contact with each other, so that the stress applied to the core 1 is alleviated and the transmission of magnetostrictive vibration to the bracket and the like is suppressed. Thus, a low-noise transformer can be realized.

(Embodiment 4) FIGS. 8, 9, 10 and 11 are front elevational views of a three-phase molded core transformer according to a fourth embodiment of the present invention. It shows a sectional view, a schematic front view of an upper coil support spacer, and a schematic side view of an upper coil support spacer.

8, 9, 10, and 11, parts having the same configurations and operations as those in FIGS. 4, 5, and 6 of the second embodiment are denoted by the same reference numerals and will be described in detail. The description is omitted, focusing on the different parts. 15 is a coil 41
Is a rubber that is a buffer material, and the coil 41
Has a protrusion in the direction of, the protrusion is cut diagonally,
The upper coil support spacer is disposed between the upper end surface of the coil 41 and the upper yoke of the iron core 1. 4, 5, and 6
The difference from the configuration of the first embodiment is that the upper coil support spacer 8 has a shape in which a portion corresponding to the coil 41 is rubber 15 which is a cushioning material, has a protrusion in the direction of the coil 41, and the protrusion is obliquely cut. The point is that the coil support spacer 15 is disposed between the upper end surface of the coil 41 and the upper yoke of the iron core 1.

A description will now be given of a transformer configured as described above. Since the upper coil support spacer 15 is disposed between the coil 41 and the upper yoke of the iron core 1,
Is supported in the vertical direction and has a projection in the direction of the coil 41, so that the distance between the iron core 1 and the low-voltage coil 2 and the distance between the low-voltage coil 2 and the high-voltage coil 3 are defined. The movement of the coil 41 in the horizontal direction due to the electromagnetic mechanical force generated when one short-circuit test is performed is suppressed. Further, when the transformer radiates heat, the air rising upward from the coil 41 reaches the upper coil support spacer 15 and the protrusion is obliquely cut, so that the resistance to air is reduced, and the air Flow smoothly and release heat.

As described above, the upper coil support spacer 15 disposed between the upper end surface of the coil 41 and the upper yoke of the iron core 1 is such that the portion corresponding to the coil 41 is rubber, which is a cushioning material. Has a protrusion in the direction, and furthermore, the protrusion is cut obliquely, so that the coil 41 can be firmly supported in the vertical and horizontal directions, and the voltage is reduced by a mechanical external force due to a short-circuit test or transportation. The device can be protected, and the flow resistance of the air for heat radiation is reduced, so that heat can be efficiently radiated.

(Embodiment 5) FIGS. 12 and 13 are an external perspective view and a schematic view of a lower coil supporting spacer according to an embodiment of the present invention.

12 and 13, parts having the same structure and operation as those in FIGS. 4, 5 and 6 of the second embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different parts will be described. I will explain mainly. 16 is a premix 1 in which a portion corresponding to the coil 41 is rubber 17 and another portion is an insulating material.
8, which is a lower coil supporting spacer having a length capable of supporting all the coils 41 and having pores in the radial direction of the coils 41. 4, 5, and 6 is that the lower coil supporting spacer 13 is a premix 18 in which a portion corresponding to the coil 41 is a rubber 17 and another portion is an insulating material, and supports all the coils 41. The point is that the lower coil supporting spacer 16 has a possible length and has pores in the radial direction of the coil 41.

Next, a description will be given of a transformer configured as described above. The lower coil supporting spacer 16 includes all the coils 41
Is long enough to support the coil 41 due to the electromagnetic mechanical force generated when the short-circuit test, which is a test item of the transformer, is performed.
Even if is moved, the risk that the corner of the support spacer hits the end face of the coil 41 to reduce the risk of damaging the coil 41 by using the individually divided support spacers as in the prior art, and perform stable coil support be able to. Further, if the length is such that all the coils 41 can be supported, the resistance of air in cooling the transformer is increased. However, the lower coil support spacer 16 in the fifth embodiment has air holes in the coil 41 in the radial direction, When the transformer is cooled, the air passing through the pores of the lower coil support spacer 16 enters the space between the coils 41 from below the coil to cool the surface of the iron core 1 and the surface of the coil 41.

As described above, the lower coil supporting spacer 1
Reference numeral 6 denotes a premix in which the portion corresponding to the coil 41 is rubber and the other portion is an insulating material. The premix has a length capable of supporting all the coils and has pores in the radial direction of the coil to improve heat radiation efficiency. In addition, the risk that the corner of the coil supporting spacer may hit the end face of the coil 41 when the coil 41 moves due to the electromagnetic mechanical force at the time of the transformer short-circuit test and the risk of damaging the coil 41 is reduced and the coil is stabilized. Support can be realized. In addition, since the length is such that all the coils 41 can be supported, the mounting is easier and the number of mounting steps can be reduced as compared with the case where a plurality of lower coil supporting spacers are mounted on the lower bracket 12.

It is to be noted that the premix 18 having pores of the lower coil support spacer 16 is formed as a lower coil support spacer 20 made of a pumice-like insulator 19 which is not a closed cell as shown in FIG. A similar effect can be obtained without the need for processing for providing. The pumice-like insulator 19 only needs to have strength enough to withstand the load applied thereto.

Note that the lower coil supporting spacer 16 is
As shown in FIG. 5, the lower coil supporting portion has a length capable of supporting all the coils 41 and a cut portion provided in the rubber 21, the portion corresponding to the coil 41 being rubber 21 and the other portion being a premix 22 made of an insulating material. When the coil 41 is supported by applying the force for supporting the coil 41 in the vertical direction by using the spacer 23, the rubber 21 has irregularities. The rubber 21 is supported in the concave direction in the vertical direction and the protrusion is in the horizontal direction. 41 can be maintained, and stable coil support can be realized.

Note that the lower coil supporting spacer 16 is
As shown in FIG. 6, a portion corresponding to the coil 41 is the rubber 24 and the other portion is a premix 22 made of an insulating material, the length is such that all the coils 41 can be supported, and the rubber 24 is a rod-shaped aggregate. By using the lower coil supporting spacer 25 having a density of 80% or more, when supporting the coil 41, a force for supporting the coil 41 in the vertical direction is applied.
The rubber has irregularities, and the concave portions support the vertical direction, and the protrusions can maintain the horizontal coil 41 interval. Further, since the rubber 24 is a rod-shaped aggregate, air can flow between them, and the heat radiation efficiency can be improved.

[0049]

As is apparent from the above description, in the dry transformer according to the first aspect of the present invention, the upper bracket has a structure in which the upper portion of the gap formed by the low-voltage coil and the iron core is opened vertically. In addition to improving heat radiation efficiency, it is possible to realize energy saving and resource saving by downsizing equipment.

The second aspect of the present invention provides a coil support that is in contact with the low-voltage coil and the high-voltage coil and the lower metal member located in the window of the lower bracket and the iron core and does not block the lower ends of the low-voltage coil and the high-voltage coil. Since the low-voltage coil and high-voltage coil are supported on the spacer, air inflow can be made more efficient,
The heat dissipation efficiency can be improved, and energy saving and resource saving by downsizing the device can be realized.

According to a third aspect of the present invention, the upper metal fitting has a structure in which a vertically upper portion of a gap formed by the low-voltage coil and the iron core is opened, and the low-voltage coil, the high-voltage coil, and the lower part are located in the window of the lower metal fitting and the iron core. The low-voltage coil and the high-voltage coil are supported by the coil support spacer that does not block the lower ends of the low-voltage coil and the high-voltage coil in contact with the metal fittings. Resource savings can be realized by downsizing.

According to the fourth aspect of the present invention, since the bottom surface of the iron core and the lower bracket have a gap without being in contact with each other, the stress of the iron core is alleviated, and the transmission of magnetostrictive vibration to the bracket and the like is suppressed. A dry transformer with low noise can be realized.

According to the fifth aspect of the present invention, since the coil supporting spacer has a projection in the coil direction, the coil spacing is defined to realize stable support, and the projection is cut obliquely. Because of the shape, the flow path resistance at the time of heat radiation is reduced, and efficient heat radiation can be realized.

According to a sixth aspect of the present invention, the lower coil supporting spacer disposed between the lower end face of the coil and the lower metal fitting is long enough to support all the coils and has pores in the radial direction of the coil. With this structure, the number of steps for attaching the lower coil support spacer can be reduced, stable coil support can be realized, and heat radiation efficiency can be improved.

Further, according to the present invention, the lower coil supporting spacer disposed between the lower end face of the coil and the lower metal fitting is long enough to support all the coils, and the cushioning material of the lower coil supporting spacer is provided. Since a cut was made in the part,
Stable support in the vertical and horizontal directions of the coil can be realized.

According to the present invention, the lower coil supporting spacer disposed between the lower end face of the coil and the lower metal fitting has a length capable of supporting all the coils, and a cushioning material for the lower coil supporting spacer. Since the portion is a rod-shaped aggregate having a density of 80% or more, stable support in the vertical and horizontal directions of the coil can be realized, and the heat radiation efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a three-phase mold-wound iron core transformer according to Embodiment 1 of the present invention.

FIG. 2 is a schematic top view of a three-phase mold-wound core transformer according to the first embodiment.

FIG. 3 is a schematic side sectional view of a three-phase molded cored transformer according to the first embodiment.

FIG. 4 is a schematic perspective view of a three-phase mold-wound core transformer according to the second embodiment.

FIG. 5 is a schematic top view of a three-phase molded cored transformer according to the second embodiment.

FIG. 6 is a schematic side sectional view of a three-phase molded cored transformer according to the second embodiment.

FIG. 7 is a schematic side sectional view of a three-phase molded cored transformer according to the third embodiment.

FIG. 8 is an external front view of a three-phase molded cored transformer according to the fourth embodiment.

FIG. 9 is a schematic partial enlarged sectional view of a three-phase molded cored transformer according to the fourth embodiment.

FIG. 10 is a schematic front view of an upper coil supporting spacer according to the fourth embodiment.

FIG. 11 is a schematic side view of an upper coil supporting spacer according to the fourth embodiment.

FIG. 12 is an external perspective view of a three-phase molded cored transformer according to the fifth embodiment.

FIG. 13 is a schematic diagram of a lower coil supporting spacer according to the fifth embodiment.

FIG. 14 is a schematic diagram of a lower coil supporting spacer according to the fifth embodiment.

FIG. 15 is a schematic diagram of a lower coil supporting spacer according to the fifth embodiment.

FIG. 16 is a schematic diagram of a lower coil supporting spacer according to the fifth embodiment.

FIG. 17 is a schematic side sectional view of a conventional dry-type transformer.

FIG. 18 is a schematic side sectional view of a conventional dry-type transformer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Iron core 2 Low voltage coil 3 High voltage coil 4 Metal fitting 5 Upper metal fitting 6 Lower metal fitting 8 Upper coil supporting spacer 9 Lower coil supporting spacer 10 Gaps between iron core and low voltage coil 11 Upper metal fitting 12 Lower metal fitting 13 Lower coil supporting spacer 14 Iron core and lower metal fitting Gap 15 Upper coil support spacer 16 Lower coil support spacer 17 Rubber 18 Premix 19 Pumice-like insulator 20 Lower coil support spacer 21 Rubber 22 Premix 23 Lower coil support spacer 24 Rubber 25 Lower coil support spacer 31 Iron core 32 Low voltage coil 33 High voltage Coil 34 Upper clamp 35 Lower clamp 36 Upper clamp 37 Lower clamp 38 Coil receiver 41 Coil

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koichi Hirakawa 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 5E043 AA07 BA01 DA01 DB01 FA01 FA04

Claims (8)

[Claims] 1. An iron core, a low-voltage coil and a high-voltage coil concentrically arranged on an outer periphery of the iron core with an interval therebetween, an upper metal member and a lower metal member, and upper and lower end surfaces of the low-voltage coil and the high-voltage coil; A coil support spacer disposed between upper and lower yoke portions of the iron core, wherein the iron core supports the low voltage and the high voltage coil, and the upper metal fitting is a vertically upper portion of a gap formed by the low voltage coil and the iron core. Dry type transformer with open structure. 2. An iron core, a low-voltage coil and a high-voltage coil concentrically arranged on the outer periphery of the iron core with an interval therebetween, an upper metal fitting and a lower metal fitting, and upper end faces of the low-voltage coil and the high-voltage coil. An upper coil support spacer disposed between upper yoke portions of an iron core; and a lower coil support spacer disposed between lower end surfaces of the low-voltage coil and the high-voltage coil and the lower metal fitting. A dry transformer in which a support spacer is in contact with the lower bracket, the low-voltage coil and the high-voltage coil, and the lower bracket, and does not block the lower ends of the low-voltage coil and the high-voltage coil located in the window of the iron core. 3. The dry-type transformer according to claim 2, wherein the upper bracket has a structure in which a vertically upper portion of a gap formed by the low-voltage coil and the iron core is opened. 4. A low-voltage coil and a high-voltage coil are supported by a lower coil support spacer, the iron core is supported by an upper coil support spacer, and a gap is provided between the bottom surface of the iron core and the lower metal fitting without contact. Item 7. A dry-type transformer according to Item 2. 5. The upper coil supporting spacer according to claim 1, wherein the upper coil supporting spacer has a projection in the direction of the low-voltage coil and the high-voltage coil, and at least a part of the projection is obliquely cut. Dry type transformer. 6. The lower coil supporting spacer according to claim 2, wherein the lower coil supporting spacer has a length capable of supporting all the low-voltage coils and the high-voltage coils, and has pores in the radial direction of the low-voltage coils and the high-voltage coils. Dry transformer as described. 7. The lower coil supporting spacer is long enough to support all of the low-voltage coil and the high-voltage coil, and at least a portion in contact with the low-voltage coil and the high-voltage coil is a material having a buffer property, and a buffer material portion The dry transformer according to any one of claims 2 to 4, wherein a cut is formed in the dry transformer. 8. The lower coil supporting spacer is long enough to support all of the low-voltage coil and the high-voltage coil, and at least a portion in contact with the low-voltage coil and the high-voltage coil is made of a material having a buffering property. The dry transformer according to any one of claims 2 to 4, wherein is a rod-shaped aggregate having a density of 80% or more.