JP3085061B2 - Axial insulation support structure for gas-insulated transformer windings - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-insulated transformer using an insulating gas such as SF6 gas as an insulating medium and a cooling medium, and to an improvement in an axial insulating support structure for insulatingly supporting a winding from its axial direction. .

[0002]

2. Description of the Related Art FIG. 8 is a cross-sectional view schematically showing a conventional axial insulating support structure of a gas insulated transformer, wherein a winding 2 concentrically wound around a main leg 1A of an iron core 1 is shown. Both ends in the axial direction are held by the support mechanism 7 via the axial insulating support member 3. That is, the support mechanism 7 comprises a pair of upper and lower frames 4, a metal press ring 5 arranged on the upper frame side, and a press ring 5 screwed to the upper frame.
And a set screw 6 for applying a predetermined tightening load in the axial direction of the winding 2 via the axial insulating support member 3.
Is supported by the iron core 1 via the support mechanism 7 while maintaining a predetermined surface pressure in the axial direction, so that the gas insulation withstands acceleration applied during transportation and electromagnetic mechanical force applied to the winding 2 during operation. A transformer winding is formed. The contents of the transformer configured as described above are housed in a tank (not shown), and are filled with an insulating gas of a predetermined pressure, thereby providing withstand voltage performance and cooling performance required as a gas insulating transformer. You.

FIG. 9 is an enlarged view of a main part schematically showing a conventional axial insulating support structure of a gas insulating transformer. The axial insulating support member 3 is formed in a ring shape corresponding to the end face of the winding 2. For example, a laminated body of an insulating plate (commonly referred to as a collar) 9 such as a press board and a square block-shaped spacer 8 radially arranged between the collars 9 is formed in a multistage shelf shape. Then, a plurality of rectangular block-shaped spacers 8 are connected to each other by a collar 9 so as to increase the buckling strength of the axial insulating support member 3. The color space configured in this way
In the axial insulation support structure of the above-mentioned type, the axial height H of the axial insulation support member 3 is determined by the insulation distance required to maintain the withstand voltage performance, and the spacing p of the spacer 8 is determined by the winding force due to the electromagnetic mechanical force. The dimensions are determined to be necessary to keep the deformation of the line within an allowable range. Accordingly, the axial insulating support 3 is required to have a function as an electrical insulating material necessary for maintaining the withstand voltage performance and a function as a mechanical support for withstanding electromagnetic mechanical force. A press board or a laminate thereof, which has been used in an input transformer, or a polyamide laminate is used. Further, in order to keep the temperature rise due to Joule heat generated by the flow of electric current below a permissible value, the cooling duct through which the insulating gas flows inside the winding is provided in the direction of the winding axis and orthogonal to the winding. It is provided in the horizontal direction. The axial insulating support 3 must function as a flow path for the insulating gas to the cooling duct in the axial direction. For this reason, the spacers 8 are radially arranged in contact with the windings and the adjacent spacers are arranged. It is configured to cool the windings by using the gas space between them as a flow path of the insulating gas.

FIG. 10 is a cross-sectional view showing a winding end of a gas-insulated transformer winding. An electrostatic shield ring 12 having an insulating coating 13 is provided at an end of the winding 2, and a space is provided on this end. −
The winding 2 is insulated and supported by the axial insulating support member 3 in contact with the support 8. The conductor portion of the electrostatic shield ring 12 is rounded to avoid concentration of an electric field, which causes a wedge-shaped gas gap 11 to be formed at the interface between the insulating coating 13 and the rectangular block-shaped spacer 8. Is done.

The electric field in the wedge-shaped gas gap 11 concentrates the electric field on the electrostatic shield ring 12, and also causes the spacer 8 (dielectric constant 3 to 4) and the insulating coating 13 (dielectric constant 2 to 2). Since an electric field inversely proportional to the dielectric constant is applied to the gas gap 11 having a dielectric constant as small as 1.0 as compared with 3), the electric field strength in the wedge-shaped gas gap 11 increases, and the local dielectric breakdown of the insulating gas in this portion. (Partial discharge) may be the starting point, which may lead to a ground fault accident in the winding.

FIG. 11 is a cross-sectional view of a main portion showing an improved conventional axial insulating support structure. The spacer portion of the axial insulating support member 3 which contacts the electrostatic shield ring 12 has an electrostatic shield. A rubber elastic body 15 having a low dielectric constant covering the ring 12 along the curved surface thereof, for example, an olefin-based elastomer;
By using (dielectric constant 2.2), the wedge-shaped gas gap 11 itself is avoided, the dielectric constant is made close to that of the gas gap, the electric field in the minute gas gap remaining at the interface between the two is relaxed, and the discharge is started. There is known a structure in which an axial insulating support structure having a high voltage is obtained (Japanese Patent Laid-Open No. 3-289110).

[0007]

In the improved conventional axial insulating support structure, the spacer 8 in contact with the electrostatic shield ring 12 is replaced with a rubber elastic body 15 having a low dielectric constant, and a wedge-shaped rubber elastic body 15 is formed. Filling the gas gap with the rubber elastic body 15 eliminates weak points on insulation, and is expected to provide an axial insulating support structure having a high discharge starting voltage. However, when a tightening load is applied in one direction, the rubber elastic body has a property of expanding to the side where no load is applied corresponding to the amount of contraction in the load direction. Therefore, even in the improved conventional axial insulating support structure, the rubber elastic body causes escape on the inner peripheral side and the outer peripheral side of the electrostatic shield ring, and the wedge-like gas is again formed on the curved portion of the electrostatic shield ring 12. It is considered that the gap 11 may be generated.
Further, the electric field in the wedge-shaped gas gap is not determined only by the dielectric constant of the rubber elastic body 15 in contact with the gas gap, but is affected by the dielectric constant of the spacers 8 and collars 9 located behind it.
That is, the electric field in the wedge-shaped gas gap is determined by the apparent dielectric constant including the rubber elastic body 15, the spacer 8, the color 9, and the gas space between or near the rubber elastic body 15, the rubber having a low dielectric constant. It is conceivable that the discharge starting voltage of the minute gas gap does not increase as expected even if an elastic body is used.

Further, in the axial spacer of the color spacer type, a minute gas gap is interposed between the winding end or the electrostatic shield ring and the spacer in contact therewith. It is necessary to increase the height H of the axial insulating support material in order to avoid the occurrence of discharge in the minute gas gap, and the axial insulating support material is increased with the height H. When the number of spacers 8 is increased in order to prevent the strength and compressive strength and buckling strength of the material from decreasing, the apparent dielectric constant of the axial insulating support material increases, and conversely, the electric field of the small gas gap increases. There is a problem of causing a vicious cycle of rising, which also causes a problem that the size of the gas insulated transformer is increased.

An object of the present invention is to provide an insulating support for a gas-insulated transformer winding capable of stably improving the discharge starting voltage of a minute gas gap at the end of the winding without impairing the mechanical rigidity of the insulating support in the axial direction. To get the structure.

[0010]

According to the present invention, a plurality of windings concentrically wound around a main leg of an iron core and a pair of windings connected to the iron core are provided. And a supporting mechanism interposed between the pair of frames and a supporting mechanism portion including the frame. The winding is interposed between the pair of frames with a predetermined tightening load via the axial insulating supporting member. In the sandwiching device, the axial insulating support is made of a corrugated material in which a plate-shaped insulating material and a corrugated insulating material are alternately laminated and bonded, and is fastened in a direction parallel to the wave of the corrugated insulating material. It shall be interposed between the winding and the support mechanism so that an applied load is applied.

An axial insulating support made of corrugated material is formed in a cylindrical shape corresponding to the shape of the axial end surface of the winding. An axial insulating support made of corrugated material formed in a cylindrical shape corresponding to the shape of the axial end surface of the winding forms a cooling gas passage penetrating the flat insulating material and communicating with the cooling duct of the winding. Shall have.

A corrugated insulating portion of an axially insulating support made of a corrugated material formed in a cylindrical shape corresponding to the shape of the axial end face of the winding penetrates the frame opposed thereto. And also serves as a cooling gas passage communicating with the cooling duct of the winding. An axial insulating support made of corrugated material is formed in a rectangular block shape, and a plurality of flat insulating materials are arranged alternately orthogonally along the circumferential direction of the axial end surface of the winding. .

[0013] It is assumed that a plurality of axially insulative support members made of corrugated material are formed in a substantially columnar shape, and are arranged in plural numbers along the circumferential direction of the axial end surface of the winding. An axial insulating support member interposed between a plurality of windings concentrically wound around the main leg of the iron core and a support mechanism including a pair of frames connected to the iron core. Wherein the winding is sandwiched between a pair of frames with a predetermined tightening load via an axial insulating support, wherein the axial insulating support is made of a porous insulating material having an insulating gas impregnating property. It shall be.

An axial insulating support made of a porous insulating material impregnating with an insulating gas is formed in a rectangular block or column shape, and a plurality of the insulating supports are arranged along the circumferential direction of the axial end surface of the winding. And An axial insulating support made of a porous insulating material having an insulating gas impregnating property is formed in a cylindrical shape corresponding to the shape of the axial end surface of the winding.

An axial insulating support made of a porous insulating material having an insulating gas impregnating property and formed in a cylindrical shape corresponding to the shape of the axial end surface of the winding is divided into a plurality of concentric cylindrical shapes.
A cooling gas passage communicating with the cooling duct is provided between the concentric cylinders.

[0016]

In the construction of the present invention, a corrugation in which an axial insulating support is alternately laminated with a flat insulating material and a corrugated insulating material.
The flat insulating material and the corrugated insulating material are both thin because they are interposed between the winding and the support mechanism so that a tightening load is applied in the direction parallel to the wave of the corrugated insulating material. Even if it is an insulating material, by forming it into a three-dimensional corrugated material, the section modulus increases and the buckling strength in the direction parallel to the wave improves, so the buckling strength withstands the axial tightening force of the winding. Can be obtained. In addition, the amount of insulating material occupying the corrugated material is reduced, and the apparent dielectric constant of the axial insulating support material is reduced to approach that of the gas gap. And the contact area between the winding and the corrugated material can be reduced to avoid the generation of minute gas gaps and wedge-shaped gas gaps. A directional insulating support structure can be obtained.

If the axial insulating support made of the corrugated material is formed in a cylindrical shape corresponding to the shape of the axial end face of the winding, the direction in which the flat insulating material of the corrugated material is defeated by shogi A slightly weaker buckling strength can be reinforced by increasing the section modulus by making it cylindrical, and the function of greatly improving the compressive strength of the axial insulating support using the same cross-sectional area of corrugated material is possible. can get. Further, a corrugation formed in a cylindrical shape corresponding to the shape of the end face in the axial direction of the winding.
A cooling gas passage which penetrates the flat insulating material and communicates with the cooling duct of the winding is formed in the axial insulating supporting material made of a metal material, or a frame facing the corrugated insulating material portion is formed. If it is configured to form a cooling gas passage that penetrates and communicates with the cooling duct of the winding, the function of cooling the winding can be obtained by using the corrugated insulating material part that is almost hollow as the cooling gas flow path. Can be

An axial insulating support made of corrugated material is formed in a rectangular block shape, and a plurality of flat insulating materials are arranged alternately orthogonally along the circumferential direction of the axial end surface of the winding. However, the buckling strength is slightly weaker in the direction in which the flat insulating material of the corrugated material defeats shogi, and the axial insulating supports in the form of adjacent square blocks reinforce each other to provide high compressive strength axial insulation. A support structure is obtained.

Even if a plurality of axial insulating support members made of corrugated material are formed in a columnar shape having a diameter close to the winding width, and a plurality of the insulating support members are arranged along the circumferential direction of the axial end surface of the winding, Utilizes the excellent buckling strength and low dielectric constant of the three-dimensional corrugated material whose buckling strength directionality is eliminated by making it cylindrical, and has excellent electromagnetic mechanical strength and voltage resistance A winding support structure is obtained.

If the axial insulating support is formed of a porous insulating material having an insulating gas impregnating property, for example, a porous ceramic material, the porous insulating material having a high gas content can uniformly disperse a large amount of insulating gas. A homogeneous low dielectric constant axial insulating support can be obtained by containing it in a dispersed state, and the electric field in the gas gap close to this is relaxed to increase the firing voltage, and the axial insulating support is formed as a rectangular block. By forming a plurality of coils in the shape of a cylinder or a column and arranging a plurality of coils along the circumferential direction of the axial end face of the winding, the winding is performed by utilizing the rigidity of the porous ceramic material having no directionality of buckling strength. An axial insulating support structure that stably withstands the axial tightening load of the wire is obtained.

If the axial insulating support made of a porous insulating material having gas impregnation properties is formed in a cylindrical shape corresponding to the shape of the axial end face of the winding, the effect of improving the section modulus is utilized. Thus, an axial insulating support structure having high buckling strength can be obtained. In addition, a plurality of axial insulating supports made of a porous insulating material having an insulating gas impregnating property and formed in a cylindrical shape having a diameter corresponding to the shape of the axial end surface of the winding are divided into a plurality of cylindrical shapes, and the cylindrical If a cooling gas passage communicating with the cooling duct is provided in the cooling air passage, both the discharge starting voltage and the differential buckling strength are high, and an axial insulating support structure including the cooling gas passage can be easily obtained.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. FIG. 1 is a cross-sectional view of a main part schematically showing an axial insulating support structure of a gas-insulated transformer winding according to a first embodiment of the present invention. By adding, duplicate description will be omitted. In the figure, an axial insulating support 21 is a corrugated plate obtained by alternately stacking and bonding a flat insulating material 22 such as a press board, a synthetic fiber paper laminate, or a fiber reinforced plastic material, and a corrugated insulating material 23. The windings 2 are formed in a cylindrical shape corresponding to the end face of the windings 2 so that an axial tightening load is applied in a direction parallel to the wave of the corrugated insulating material 23.
By applying a predetermined tightening load via the press ring 5 with the set screw 6, the winding 2 is interposed between the press mechanism 5 and the press ring 5 of the support mechanism 7 and between the lower frame 4. It is insulated and supported between the support mechanisms while holding the tightening load. The thickness of the flat insulating material 22 and the thickness of the corrugated insulating material 23 are determined in consideration of the axial tightening load.
By setting the thickness to about several mm, an axial insulating support member having a desired buckling strength that can withstand an axial tightening load can be obtained. In addition, the apparent dielectric constant of the corrugated material can be reduced to 2 or less without impairing the buckling strength by determining the wave height of the corrugated insulating material 23.

In the axially insulated support structure thus constructed, both the flat insulating material 22 and the corrugated insulating material 23 are made of an insulating material such as a thin press board, synthetic fiber paper, or fiber reinforced plastic material. Even if this
The buckling strength can be increased by forming a composite material, and the direction of the buckling strength can be covered by improving the section modulus by making it a cylindrical shape. A strong axial insulating support structure can be obtained. Further, the amount of the insulating material in the corrugated material is reduced, and accordingly, the axial insulating supporting material 21 is reduced.
Since the apparent dielectric constant of the gas gap is reduced to approach that of the gas gap, it is possible to reduce the shared voltage that the small gas gap bears based on the principle of the capacitance partial pressure and to reduce the color.
・ The contact area between the winding and the corrugated material is greatly reduced as compared with the spacer type axial insulating support structure, and the generation of a small gas gap or a wedge-shaped gas gap can be avoided. An axial insulating support structure with high insulation reliability and high reliability can be obtained. Further, since it is not necessary to increase the height H of the axially insulating support material conventionally required to increase the discharge starting voltage of the gas gap, it is possible to reduce the size of the gas insulating transformer and increase the height H. Since the reduction leads to an increase in the buckling strength and a reduction in the apparent permittivity of the corrugated material, there is obtained an advantage that a vicious cycle which has been a problem in the past is cut off and the axial insulating support structure is rationalized.

FIG. 2 is a perspective sectional view showing a main part of an axial insulating support structure according to a second embodiment of the present invention, partially cut away, and shows a cylinder corresponding to the shape of the axial end surface of the winding 2. An axial insulating support member 21 made of a corrugated material having a through-hole is provided with a through hole 25 penetrating through the flat insulating material 22, and passes through the inside of the cylindrical corrugated material to cool the winding 2 in the axial direction. This embodiment is different from the above-described embodiment in that a cooling gas passage 27 communicating with the duct 2D is formed, and a portion of the corrugated insulating material 23 which is almost hollow is used as a cooling gas flow passage to form an axial insulating support structure. The advantage is obtained that the winding can be efficiently cooled without adversely affecting the buckling strength and the withstand voltage performance.

FIG. 3 is a simplified cross-sectional view showing an axial insulating support structure according to a third embodiment of the present invention, which is opposed to a corrugated insulating member 23 of a cylindrical axial insulating support member 21. A through hole 28 is provided in the frame 4 to be
Is different from the above-described embodiments in that a cooling gas passage 29 communicating with the cooling duct 2D of the winding is formed along the surface of the coil. By utilizing the material 23 for the flow path of the cooling gas, there is obtained an advantage that the winding can be efficiently cooled without adversely affecting the buckling strength and the withstand voltage performance of the axially insulating support structure.

FIG. 4 is a perspective view showing an axial insulating support member according to a fourth embodiment of the present invention, in which an axial insulating support member 31 made of corrugated material is formed in a rectangular block shape, and is wound. Is different from the above-described embodiments in that a plurality of plate-like insulating materials 22 are arranged so as to be alternately orthogonal to each other along the circumferential direction of the axial end surface of the corrugated material. The buckling strength is slightly weaker in the direction in which the shogi is defeated, and the adjacent rectangular block-shaped axial insulating support members 31 reinforce each other to obtain an axial insulating support structure having a high compressive strength. By cutting the material into desired dimensions, the advantage is obtained that the axial insulating support 31 can be easily formed.

FIG. 5 is a perspective view showing an axial insulating support according to a fifth embodiment of the present invention.
1, a flat corrugated insulating material 22 and a corrugated insulating material 23 are adhered to each other in a state of being wound in a cylindrical shape having the maximum diameter of the winding 2 so as to form a cylindrical corrugated material; The present embodiment is different from the above embodiments in that a plurality of the corrugated members are formed in a spiral shape or a multi-cylindrical shape having a small diameter. The flexural strength is obtained, and the advantage is obtained that the columnar axial insulating support member 41 can be easily formed by cutting a long cylindrical corrugate material into a desired size.

FIG. 6 is a perspective view showing an axial insulating support according to a sixth embodiment of the present invention.
1 is made of a porous insulating material having an insulating gas impregnating property, for example, a porous ceramic material or a porous plastic material, which is different from the above-described embodiments. By containing the insulating gas in a uniformly dispersed state, a homogeneous low dielectric constant axial insulating support member 51 is obtained, and the electric field in the gas gap adjacent to the insulating support member 51 is relaxed to increase the discharge starting voltage. The insulating support member 51 may be formed in a rectangular block shape as shown in FIG.
Alternatively, by forming a plurality of cylinders in a columnar shape and arranging a plurality of them along the circumferential direction of the end surface in the axial direction of the winding 2, the winding is performed by utilizing the rigidity of the porous ceramic material having no buckling strength directionality. An axial insulating support structure that stably withstands the axial tightening load of the wire is obtained.

FIG. 7 is a sectional view showing an axial insulating support structure according to a seventh embodiment of the present invention. A multi-cylindrical shape is formed according to the shape of the axial end surface of the winding 2 having the duct 2D, and a gap between the multi-cylindrical axial insulating support members 61 is defined as a cooling gas passage 67. Through hole 65 formed in
This embodiment is different from the above-described embodiment in that the winding is gas-cooled through the through hole 66 formed in the drum 4, and the dielectric constant can be further reduced by providing the cooling gas passage 67 between the multiple cylinders. And the function of eliminating minute gas gaps can be obtained, so that discharge is started using the effect of improving the buckling strength obtained by using a cylindrical shape and the effect of reducing the dielectric constant obtained by using a porous insulating material. An axially insulated support structure for a gas-insulated transformer winding having a high voltage and excellent mechanical stability can be obtained. Note that the multi-cylindrical axial insulating support members 61 may be configured to be mutually connected and integrated by a spacer made of the same material, and an effect of further improving mechanical stability can be obtained.

[0030]

As described above, according to the present invention, the winding is insulated and supported between the axial ends of the winding and the supporting mechanism including the frame while maintaining a predetermined tightening load and withstand voltage strength. A corrugated insulator made of insulating material
Material, or configured to use a porous insulating material, as a result, without impairing the buckling strength of the axial insulating support,
It is possible to reduce the dielectric constant of the axial insulating support,
It is possible to provide a gas insulating transformer provided with an axial insulating support structure having a high discharge starting voltage by alleviating electric field concentration in a minute gas gap or a wedge-shaped gas gap, which has conventionally been a problem.

Further, if the corrugated material or the porous insulating material is formed into a cylindrical shape or a multi-cylindrical shape corresponding to the shape of the winding end portion, and a cooling gas passage is formed therein, the cylindrical shape can be obtained. By doing so, the effect of improving the buckling strength is obtained, and the function of eliminating the small gas gap by reducing the contact area with the winding end face is obtained. Provide a gas-insulated transformer that enables reduction of the height of the directional insulating support material, has high stability of the discharge starting voltage and mechanical strength, is compact, and has an axial insulating support structure including a cooling gas passage. can do.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part schematically illustrating an axial insulating support structure of a gas-insulated transformer winding according to a first embodiment of the present invention.

FIG. 2 is a perspective sectional view showing a main part of an axial insulating support structure according to a second embodiment of the present invention, partially cut away;

FIG. 3 is a simplified sectional view showing an axial insulating support structure according to a third embodiment of the present invention.

FIG. 4 is a perspective view showing an axial insulating support according to a fourth embodiment of the present invention.

FIG. 5 is a perspective view showing an axial insulating support according to a fifth embodiment of the present invention.

FIG. 6 is a perspective view showing an axial insulating support according to a sixth embodiment of the present invention.

FIG. 7 is a sectional view showing an axial insulating support structure according to a seventh embodiment of the present invention.

FIG. 8 is a cross-sectional view schematically showing a conventional axial insulating support structure of a gas insulating transformer.

FIG. 9 is an enlarged view of a main part schematically showing a conventional axial insulating support structure of a gas insulating transformer.

FIG. 10 is a sectional view showing a winding end of a gas-insulated transformer winding.

FIG. 11 is a sectional view of a main part showing an improved conventional axial insulating support structure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Iron core 2 Winding 2D cooling duct (axial direction) 3 Axial insulating support material 4 Frame 5 Press ring 6 Set screw 7 Support mechanism 8 Spacer 9 Color 11 Wedge-shaped gas gap 12 Electrostatic shield ring DESCRIPTION OF SYMBOLS 13 Insulation coating 15 Low dielectric constant rubber elastic body 21 Axial insulating support material (cylindrical corrugated material) 22 Flat insulating material 23 Corrugated insulating material 25 Through hole 27 Cooling gas passage 28 Through hole 29 Cooling gas passage 31 Axial insulating support (square block corrugated material) 41 Axial insulating support (cylindrical corrugated material) 51 Axial insulating support (square block porous ceramic material) 61 Axial insulating support (Multiple cylindrical porous ceramic material) 65 Through hole 66 Through hole 67 Cooling gas passage

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01F 27/20

Claims (10)

(57) [Claims] A shaft interposed between a plurality of windings concentrically wound around a main leg of an iron core and a support mechanism including a pair of frames connected to the iron core. Directional insulating supporting material, wherein the winding is sandwiched between a pair of frames with a predetermined tightening load via the axial insulating supporting material, wherein the axial insulating supporting material and the flat insulating material are corrugated. It is made of a corrugated material in which plate-like insulating materials are alternately laminated and bonded, and is interposed between the winding and the support mechanism so that a tightening load is applied in a direction parallel to the wave of the corrugated insulating material. An axially insulated support structure for a gas-insulated transformer winding. 2. The gas-insulated transformer winding according to claim 1, wherein the axial insulating support made of corrugated material is formed in a cylindrical shape corresponding to the shape of the axial end surface of the winding. Axial insulation support structure for wires. 3. An axial insulating support made of a corrugated material having a cylindrical shape corresponding to the shape of the axial end surface of the winding, penetrates the flat insulating material and communicates with the cooling duct of the winding. 3. The axially insulated supporting structure of a gas-insulated transformer winding according to claim 2, further comprising a cooling gas passage. 4. A corrugated insulating portion of an axially insulating support made of a corrugated material having a cylindrical shape corresponding to the shape of the axial end surface of the winding forms a frame facing the same. 3. The axially insulated supporting structure of a gas-insulated transformer winding according to claim 2, wherein the cooling gas passage penetrates and communicates with a cooling duct of the winding. 5. An axial insulating support made of a corrugated material is formed in a rectangular block shape, and a plurality of flat insulating materials are arranged alternately orthogonally along a circumferential direction of an axial end surface of a winding. The axially insulated support structure for a gas-insulated transformer winding according to claim 1, characterized in that: 6. An axially insulative support member made of a corrugated material is formed in a substantially columnar shape, and a plurality of axially insulated support members are arranged along a circumferential direction of an axial end surface of the winding. An axial insulation support structure for the gas-insulated transformer winding described. 7. A shaft interposed between a plurality of windings concentrically wound around a main leg of an iron core and a support mechanism including a pair of frames connected to the iron core. An axial insulating support, wherein the winding is sandwiched between a pair of frames with a predetermined tightening load via the axial insulating support, wherein the axial insulating support has an insulating gas impregnating property. An axial insulating support structure for a gas-insulated transformer winding, comprising a porous insulating material. 8. A plurality of axial insulating supports made of a porous insulating material having an insulating gas impregnating property are formed in a rectangular block shape or a cylindrical shape, and are arranged along a circumferential direction of an axial end surface of a winding. The axially insulated support structure for a gas-insulated transformer winding according to claim 7, wherein 9. An axial insulating support made of a porous insulating material having an insulating gas impregnating property is formed in a cylindrical shape corresponding to a shape of an axial end face of a winding.
An axial insulation support structure for the gas-insulated transformer winding described. 10. An axial insulating support made of a porous insulating material having an insulating gas impregnating property and having a cylindrical shape corresponding to the shape of the axial end surface of the winding is divided into a plurality of concentric cylinders, and is concentrically divided. 9. The axially insulated supporting structure of a gas-insulated transformer winding according to claim 8, further comprising a cooling gas passage communicating between the cylinders and the cooling duct.