JP3544753B2 - Stationary induction appliance - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a static induction device such as a transformer or a reactor, and more particularly to a static induction device having a lead wire insulating support structure in a lead duct portion.
[0002]
[Prior art]
Usually, the transformer lead wire is led out from the winding end of the transformer to the lower terminal of the bushing, but is connected to the bushing pocket for holding the bushing via a lead duct from the tank container body storing the contents of the transformer on the way. Configuration may be taken. In this case, in order to ensure that the lead wire has a predetermined withstand voltage with respect to the lead duct, the insulated and coated insulated lead wire is held by a lead support plate at a plurality of locations in the lead duct to ensure a predetermined insulation distance. ing.
[0003]
When the voltage applied to the lead wire is high, as a means for increasing the creepage length of the support plate from the lead wire to the lead duct in order to improve the withstand voltage, the lead support plate is not fixed directly from the lead duct, as shown in FIG. As shown in (1), after the lead support 9 is once fixed to the lead duct 1, a lead support plate 6 for supporting the lead wire 3 is connected and fixed to the lead support 9 (Japanese Patent Laid-Open No. 57-57). 194511).
[0004]
Further, with respect to the lead support structure not inside the lead duct but inside the transformer contents storage tank container, a device has been proposed in which impurity particles hardly settle on the upper side surface of the lead support plate. For example, as shown in FIG. 9 of a plan view and FIG. 10 of a vertical sectional view of a main part of a lead wire supporting device inside a conventional transformer tank, a lead having a lead conductor inside in a vertical rising portion of the lead wire 3. A spacer 4 having an inclined surface which is tapered between a vertical rising portion of the wire 3 and a supporting plate 6 supporting the lead wire 3 so as to taper from the upper surface of the supporting plate 6 toward the rising direction of the lead wire 3. 5 are arranged radially, and the lead wire 3 is supported and fixed to the support plate 6 via the spacer 4 and the insulating bar 5. Reference numeral 7 denotes an insulating stud, 15 denotes a winding, 16 denotes an iron core clamp, and 17 denotes an iron core (see Japanese Patent Application Laid-Open No. 54-65328).
[0005]
The above-mentioned conventional technology is considered to be useful for reducing the shared voltage applied to the surface of the insulator or preventing precipitation of impurity particles when the voltage applied to the lead wire is not so high yet or in the case of a lead support structure in the tank container. .
[0006]
[Problems to be solved by the invention]
However, when the voltage applied to the lead wire is very high, such as a 500 KV class transformer or a 1000 KV class transformer, or when the lead duct is in a horizontal configuration or inside the lead duct, the withstand voltage performance is sufficient. Or the withstand voltage performance may decrease.
[0007]
The present invention has been made in view of the above circumstances, and its purpose is to withstand a withstand voltage with respect to a lead wire to which a very high voltage is applied, regardless of the arrangement of the lead duct, in a narrow space inside the lead duct. An object of the present invention is to provide a static induction device having an excellent lead wire insulating support structure.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention is a stationary induction device including a lead connection device for arranging an insulated lead wire covered with insulating paper on the outer periphery of a conductor via a lead support plate in a lead duct. In an electric appliance, an insulating bar rear wound around an oil passage provided outside the insulated lead wire, a support plate divided into at least two for sandwiching and supporting the insulating bar rear, and a lead fixed to the lead duct A support column and an insulating stud for fixing the support plate to the lead column are provided, and the support plate has a shape in which a corner on a lead duct side is cut off .
[0009]
According to a second aspect of the present invention, in the stationary induction apparatus according to the first aspect, the cross section of the lead duct is a cylinder, and a press board is provided at least below the inner peripheral surface of the lead duct. And
According to a third aspect of the present invention, in the static induction device according to the first aspect, only the outermost one of the insulating varia disposed outside the insulated lead wire and directly contacting the lead support plate has a length in the lead axial direction. It is characterized by having a small size .
[0012]
[Action]
According to the stationary induction device of the present invention, by arranging a plurality of insulating barriers provided with oil passages on the outside of the insulating lead wire, the strength of the creeping electric field on the lead wire side of the support plate holding the lead wire is reduced. In addition, since the supporting plate is fixed to the lead duct via the lead supporting column, the voltage shared by the supporting plate is also reduced, so that the electric field intensity applied to the supporting plate supporting the lead wire can be reduced and the creepage shared voltage can be reduced. And high insulation performance can be obtained.
[0013]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a radial cross-sectional view of a lead wire supporting device in a lead duct according to a first embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a main part of the lead wire supporting device of FIG.
[0014]
As shown in the figure, an insulating lead wire 3 insulated from a lead conductor 2 has an insulating barrier 5 disposed only on a multi-layer lead wire support portion via an oil gap retaining spacer 4. The insulating bar rear 5 is held by being sandwiched by two lead supporting plates 6 divided from the outside of the insulating bar rear 5, and the lead supporting plate 6 is fixedly fastened to the lead supporting columns 9 by the insulating studs 7. Further, the support seat 11 and the lead support pillar 9 which are welded and fixed to the cylindrical lead duct 1 are tightened and fixed by an insulating stud 8 via an L-angle insulating member 10 which is an L-shaped insulating member.
[0015]
Since the lead supporting portion in the lead duct 1 is configured as described above, the creeping electric field strength of the lead supporting plate 6 on the side of the insulating barrier 5 decreases in inverse proportion to the distance from the center of the lead conductor 2. By increasing the overall creepage distance of the support plate 6 and the support column 9 by interposing the lead support column 9 between the lead support plate 6 and the lead duct 1, or reducing the creepage distance of the support plate 6 By doing so, the voltage (shared voltage) shared by the support plate 6 is reduced.
[0016]
Further, also on the side of the lead duct 1 which is at the ground potential, the support seat 11 for fixing the support post 9 has a flat shape with a curvature on the lead wire side, so that the electric field intensity is also reduced. Since the L-angle insulating member, which is an L-shaped insulating member, is disposed between the support seats 11, a configuration is such that discharge from the ground electrode side is unlikely to occur and spread.
[0017]
As described above, according to the present embodiment, the local electric field intensity applied to the creeping surface of the lead support plate 6 on the high voltage side can be reduced and the creeping voltage can be reduced, and the insulation strength against creeping discharge can be increased. In addition, discharge is less likely to occur and spread from the support seat 11 welded and fixed to the lead duct 1 at the ground potential, and the lead wire supporting device according to the present embodiment is generally balanced and has a high voltage in the lead duct. Has excellent insulation performance against
[0018]
FIG. 3 is a radial sectional view of a lead duct of a lead wire supporting device according to a second embodiment of the present invention. In addition, already the first embodiment and the same parts described are denoted by the same reference numerals, and a description thereof will be omitted.
[0019]
This embodiment is different from the first embodiment in that the lead wire supporting plate 6 has a shape in which a corner portion facing the lead duct 1 is cut off. By forming the support plate 6 in such a shape, the creepage distance from the insulating bar rear 5 to the lead duct 1 is reduced. Therefore, the creeping voltage of the support plate 6 is reduced, and the insulation performance is improved as compared with the first embodiment under the same lead duct diameter and the same insulating barrier structure.
[0020]
FIG. 4 is a sectional view of a lead wire supporting device according to a third embodiment of the present invention in a radial direction of a lead duct. Incidentally, already subjected to the above identical reference numerals in the first embodiment and the same parts described, and a description thereof will be omitted, and only different portions will be explained.
[0021]
In the present embodiment, the length of the spacer 4 between the insulating bar and the insulating bar 5 disposed outside the insulating lead 3 and the length of the spacer 4 between the insulating bar 5 are determined by the axial length of the insulating lead of the insulating bar. It is configured such that the spacer 4 is disposed inside from the opening end of the insulating bar rear 5.
[0022]
By adopting such an insulating bar rear configuration, the insulating bar rear 5 and the end faces of the spacers 4 are prevented from being aligned on a plane from the insulating surface of the insulating lead wire 3 to the outermost position of the insulating bar rear 5.
[0023]
When the end faces of the insulating barrier 5 and the spacer 4 are aligned on a plane, the thickness of the insulating paper of the insulating lead wire 3 is not sufficient, and when the radial dimension of the spacer 4 is large and the number of insulating barrier layers increases, the plane on the plane is increased. The creeping voltage is increased, and creeping discharge is easily generated. Therefore, by making the length of the spacer 4 shorter than the length of the insulating barrier 5 so that the end surfaces of the insulating barrier 5 and the spacer 4 are not aligned, the creepage length via the end surface of the spacer 4 can be greatly increased. In addition, the insulation performance can be further improved as compared with the second embodiment.
[0024]
FIG. 5 is a radial sectional view of a lead duct of a lead wire supporting device according to a fourth embodiment of the present invention. In addition, already the first embodiment and the same parts described are denoted by the same reference numerals, and a description thereof will be omitted.
[0025]
In the present embodiment, a grounding barrier 12 made of a press board or the like is disposed only on the lower part of the inner peripheral surface of the horizontally arranged lead duct 1 so as to be as close as possible. Small foreign matter is likely to collect in the lower part inside the lead duct 1, and in the case of a bare electrode, although a low probability, dielectric breakdown may occur at a low voltage. However, insulation protection at low voltage can be prevented by insulatingly protecting the bare electrode portion.
Therefore, by disposing the grounding barrier 12 on the inner peripheral lower surface of the lead duct 1 as in the present embodiment, a lead wire supporting structure with high insulation reliability can be obtained.
[0026]
In addition, as a mounting range of the grounding bar rear 12 on the inner peripheral lower surface of the lead duct 1, it is preferable that the longitudinal direction of the lead duct be 60 ° or more from the vertical with respect to the circumferential direction over the entire length in order to prevent foreign matter accumulation. When the voltage is further increased and it is necessary to increase the reliability, it is desirable to dispose the ground barrier 12 over the entire inner circumference of the lead duct 1 as shown in FIG.
[0027]
In the case of the present embodiment, the arrangement of the grounding barrier 12 is limited to the horizontally arranged lead duct, but a modification of the embodiment is not limited by the arrangement of the lead duct. Also, the case where the horizontal inclination of the lead duct is in a range of 45 ° or less from the horizontal position is included in the present embodiment.
[0028]
FIG. 7 is a longitudinal sectional view of a lead wire supporting device according to a fifth embodiment of the present invention. Note that the same reference numerals are given to the same portions as those of the embodiments described above, and description thereof will be omitted.
[0029]
The difference of the lead wire supporting device of the present embodiment from the above embodiments is that an insulating barrier 14 is also provided on the general portion of the insulated lead wire 3 and a short insulating barrier 13 is added to the lead wire supporting portion. The point is that they are arranged. Such a configuration is effective when the thickness of the insulating paper layer of the lead wire 3 is relatively small, and the operation and effect of the lead wire supporting device are the same as those of the above-described embodiments.
[0030]
In each of the above embodiments, it is desirable that the lead wire support plate 6, the support pillar 9 and the L-shaped insulator 10 be made of a press-board material having excellent withstand voltage made of only kraft pulp. Further, among the insulating studs, it is desirable to use a voidless FRP for the insulating stud 7 for fastening and fixing the support plate 6 and the support column 9 to a high electric field when the lead wire voltage is high.
[0031]
【The invention's effect】
As described above, according to the present invention, a plurality of insulating barriers having oil passages provided outside the lead wires are arranged, and the outer periphery of the outermost insulating barrier is sandwiched by at least two divided support plates. In addition, since the support plate is configured to be fixedly fastened to the lead support pillar fixed to the lead duct with an insulating stud, the electric field intensity applied to the surface of the lead support plate is reduced, and the creepage shared voltage is also reduced at the same time. Therefore, it is possible to provide a stationary induction device having a lead wire support structure having excellent insulation performance even with respect to a high voltage of the lead wire.
[Brief description of the drawings]
FIG. 1 is a sectional view in a radial direction of a lead duct according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view of FIG.
FIG. 3 is a sectional view in a radial direction of a lead duct according to a second embodiment of the present invention.
FIG. 4 is a longitudinal sectional view of a third embodiment of the present invention.
FIG. 5 is a sectional view in a radial direction of a lead duct according to a fourth embodiment of the present invention.
FIG. 6 is a sectional view of a modification of the fourth embodiment of FIG. 5;
FIG. 7 is a longitudinal sectional view of a fifth embodiment of the present invention.
FIG. 8 is a sectional view of a conventional lead duct supporting apparatus in a lead duct in a radial direction of the lead duct.
FIG. 9 is a plan view of a conventional lead wire support device inside a transformer tank.
FIG. 10 is a longitudinal sectional view of FIG. 9;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Lead duct, 2 ... Lead conductor, 3 ... Insulated lead wire, 4 ... Spacer, 5 ... Insulated bar rear, 6 ... Support plate, 7 ... Insulated stud, 8 ... Insulated stud, 9 ... Support pillar, 10 ... El angle, 11: Supporting seat, 12: Grounding barrier, 13, 14: Insulating barrier, 15: Winding, 16: Iron core clamp, 17: Iron core.

Claims (3)

In a stationary induction electric machine having a lead connection device for arranging an insulating lead covered with insulating paper on the outer periphery of a conductor via a lead support plate in a lead duct, an oil path is provided outside the insulating lead and wound. A rotating insulating barrier, a support plate divided into at least two supporting and sandwiching the insulating barrier, a lead support fixed to the lead duct, and an insulation fixing the support plate to the lead support. A stationary induction electric machine comprising a stud and a shape in which a corner of a side of a lead duct of the support plate is cut off . 2. The stationary induction device according to claim 1, wherein the lead duct has a cylindrical cross section, and a press board is disposed at least below the inner surface of the lead duct . 2. The stationary induction device according to claim 1, wherein, of the insulating barriers disposed outside the insulating lead wire, only the outermost insulating barrier in direct contact with the lead support plate has a reduced length in the lead axis direction. To a stationary induction device.

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