JPH1131628A - Stationary induction apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized stationary induction apparatus of high insulating reliability by a method, wherein the electric field of corner part of the winding conductor of a disc-shaped winding is reduced, the insulation intensity of the winding is enhanced and the dimension and the weight of the apparatus are decreased. SOLUTION: In this apparatus, a plurality of disc-shaped coils 2, which re wound on the winding conductor 3 insulated by an insulation-coating 4, are stacked in axial direction and are series-connected, the radial directioned duct piece 5 between each coil 2 is arranged equally radially on the circumference, and a radially-directed cooling duct piece 6 is formed. A longitudinal duct piece 7 is arranged on the notched part provided on the inner terminal of the radial duct piece 5, the radially directed duct piece 5 is arranged equally and fixed on the circumference of the disc-shaped coil 2, and a longitudinal direction duct piece 8 is formed. A shield conductor 9, having a potential equal to that of the winding conductor 3 of the innermost side of the disc-shaped coils 2 and having a<b relation between the width (b) of the winding conductor 3 in winding axial direction and the width (a) of a shield conductor 9, is wound by one turn in 9 disc form on the inside in radial direction of the winding conductor 3 of the coils 2, and a disc-shaped winding 1 is constituted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stationary induction device such as a transformer or a reactor, and more particularly to an electric field at a corner portion of a winding conductor of a disk-shaped coil to enhance insulation strength of the winding. , Reducing the size and weight of the winding.

[0002]

2. Description of the Related Art As windings of stationary induction equipment such as transformers and reactors, there are generally disk-shaped windings such as a disk winding, a high series capacity winding and a helical winding.

[0003] Ordinary disk winding is a duct piece (interval piece, in this specification, a diameter piece) which is arranged at an appropriate interval equally spaced in the circumferential direction between disk-shaped disk coils wound in the radial direction. (Referred to as a directional duct piece) in the axial direction. Then, a vertical duct piece for forming a passage (hereinafter, referred to as a cooling duct) for insulating oil (or an insulating cooling medium such as air or insulating gas) on the outer periphery of the insulating cylinder is equally spaced in a circumferential direction at appropriate intervals. , And a disk coil is arranged on the outer periphery. A vertical duct piece is disposed in a notch provided at an inner end or both ends of the radial duct piece, and the radial duct piece is fixed to form a vertical cooling duct between the vertical duct pieces, A radial cooling duct is formed between the duct pieces to form a normal disk winding.

[0004] The high series capacity winding is also called a Heizer cap winding and is formed by winding a winding having a fixed winding difference between each winding of the disk coil.

[0005] The helical winding is also called a Wendel winding, and is formed by stacking a plurality of winding conductors in the radial direction and spirally winding in the axial direction via a radial duct piece.

The longitudinal sections of the ordinary disk winding, the high series capacity winding and the helical winding have almost the same shape. Therefore, the present invention includes a disk-shaped winding including these three types of windings. It is called a winding.

FIG. 5 is a sectional view of a disc-shaped winding of a conventional stationary induction machine. In FIG. 5, a plurality of disc-shaped coils 2 wound with a winding conductor 3 are interposed via a radial duct piece 5. The radial duct pieces 5 between the disc-shaped coils 2 are radially and equally arranged on the circumference to form a radial cooling duct 6. Provided at both ends of the directional duct piece 6 (both ends when other windings are arranged outside) or at inner ends (only inside ends when other windings are not arranged outside) A vertical duct piece 7 is arranged in the cutout, and the radial duct pieces 6 are equally arranged on the circumference of the disc-shaped coil 2 and fixed, and a vertical cooling duct 8 is formed.

FIG. 6 is a cross-sectional view of a main portion of a conventional stationary induction device in the vicinity of a vertical duct piece 7 of a disc-shaped coil having a disc-shaped winding.
In FIG. 6, a disc-shaped coil 12 in which a winding conductor 3 insulated by winding an insulating coating 4 such as kraft paper around a rectangular wire as a conductor is wound around the outer periphery of an inner vertical duct piece 7 is a radial duct piece. The disk winding 11 is formed by superimposing in the axial direction of the winding via the wire 5.

In such a disk-shaped winding 11, the contact portion between the corners of the winding conductor 3 or the winding conductor 3
A small gap Δ is formed at the contact portion between the corner of the vertical duct piece 7 and the radial duct piece 5, and the electric field is remarkably concentrated.

Therefore, as shown in FIG. 7, a non-fibrous porous soft insulating sheet 13 is provided between the winding conductor 3 of the disc-shaped coil 12 and the radial duct piece 5,
Similarly, a so-called minute gap filling method in which a soft insulating sheet 13 is provided between the winding conductor 3 and the vertical duct piece 7 is employed. In this case, the arrangement of the soft insulating sheet in the vicinity of the disc-shaped coil has a problem that the number of parts is large and the cost is high.

[0011]

In the disk-shaped winding of the stationary induction machine described in the prior art, the contact between the corners of the winding conductor or the corner of the winding conductor and the vertical portion. A minute gap is formed at the contact point with the duct piece or the radial duct piece, and the electric field is remarkably concentrated.If the minute gap is filled with a soft insulating sheet, the heat dissipation effect decreases, the cooling effect decreases, the temperature decreases. There were problems such as an increase in the rise.

The present invention has been made in view of the above-mentioned problems of the prior art, and alleviates an electric field at a corner portion of a winding conductor of a disk-shaped winding to increase the insulation strength of the winding. It is another object of the present invention to provide a compact static induction device having high insulation reliability with reduced size and weight.

[0013]

In the present invention, means for solving the above-mentioned problems include: a radially inner side of a winding conductor of a disk-shaped coil of a stationary induction machine; And a shield conductor having the same potential as that of the winding conductor is wound one turn to form a disc-shaped winding. Thus, the shield conductor having the same potential as the innermost winding conductor of the disc-shaped coil is wound one turn inside the radial direction of the winding conductor of the disc-shaped coil of the stationary induction device, and the disc-shaped coil is wound. By configuring the winding, the insulation distance can be reduced, the coil height can be reduced, and the coil can be reduced in size, so that a reduced-sized stationary induction winding having improved insulation reliability can be obtained.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a main part of a disk-shaped winding portion of a stationary induction machine according to a first embodiment of the present invention, wherein 1 is a disk-shaped winding, and the disk-shaped winding 1 is And a shield conductor 9 is provided inside the disc-shaped coil 2 in the radial direction.

That is, the disk-shaped winding 1 of the present invention comprises a plurality of disk-shaped coils 2 wound around a winding conductor 3 insulated by an insulating coating 4 wound with an insulating tape such as kraft paper tape. The radial duct pieces 5 between the respective disc-shaped coils 2 are radially and equally arranged on the circumference to form a radial cooling duct 6, and the radial duct pieces 5 A vertical duct piece 7 is disposed in a cutout provided at least at an inner end of the disk coil 2 and the radial duct pieces 5 are equally disposed on the circumference of the disc-shaped coil 2 and fixed. A shield conductor 9 having the same potential as the innermost winding conductor 3 of the disc-shaped coil 2 is wound around the inside of the winding conductor 3 of the disc-shaped coil 2 in the radial direction for one turn.

Although the shield conductor 9 is formed by winding one turn, it is not required to be exactly one turn, and there may be a slight gap between both end faces, or a part of the shield may be wrapped.
Both ends are formed so as not to be short-circuited.

The shield conductor 9 is connected to the innermost winding conductor of the disc-shaped coil 2 by a lead wire or the like, and is set to the same potential.

The width dimension a of the shield conductor 9 is shorter than the width dimension b of the winding conductor 3 in the direction of the winding axis (a <b).

By providing the shield winding 9 formed in this way, the electric field at the corner curvature portion of the winding conductor 3 of the disc-shaped winding 1 is reduced as shown in FIG.

FIG. 2 is a sectional view of a main part of a second embodiment of the present invention. In FIG. 2, the innermost part of the disc-shaped coil 2 is disposed radially inside the winding conductor 3 of the disc-shaped coil 2. And the relationship between the width b of the winding conductor 3 in the winding axis direction of the disk-shaped winding 1 and the width a of the shield conductor 9 is a <b.
The periphery of the shield conductor 9 is insulated by a resin mold 10 and the width of the resin mold 10 in the winding axis direction is made equal to the width c of the winding conductor 3 in the winding axis direction after insulation. 1.

Thus, the electric field E at the curvature of the corner of the winding conductor 3 of the disc-shaped winding 1 can be reduced.

FIG. 3 is a sectional view of a main part of a third embodiment of the present invention. In FIG. 3, the innermost part of the disc-shaped coil 2 is disposed radially inside the winding conductor 3 of the disc-shaped coil 2. And the relationship between the width b of the winding conductor 3 in the winding axis direction of the disk-shaped winding 1 and the width a of the shield conductor 9 is a = b.
Thus, the curvature of the corner of the shield conductor 9 on the inner surface side of the disc-shaped coil 2 is made larger than the curvature of the corner of the winding conductor 3.

Thus, the electric field at the curvature of the corner of the winding conductor 3 of the disc-shaped winding 1 can be reduced.

FIG. 4 is a comparison diagram of the electric field at the coil end of the disk-shaped winding of the conventional stationary induction device and the coil end of the disk-shaped winding of the stationary induction device of the present invention. Is a state diagram of the electric field at the coil end of the disc-shaped winding of the conventional stationary induction device,
(B) is a state diagram of the electric field at the coil end of the disc-shaped winding of the stationary induction device of the present invention. Or outside)
By winding the shield conductor 9 having the same potential as that of the winding conductor 3 and having a large curvature, the corner electric field E of the winding conductor 3 is reduced. That is, the interval between the equipotential lines at the coil end of the disk-shaped winding of the stationary induction device of the present invention is smaller than the interval between the equipotential lines at the coil end of the disk-shaped winding of the conventional stationary induction device. Thus, the electric field E1 at the conventional corner is E1 <E2 as compared with the electric field E2 at the corner according to the present invention.

As described above, the electric field E at the curvature of the corner of the winding conductor 3 of the disc-shaped winding 1 can be reduced.

[0027]

According to the stationary induction device of the present invention, a shield conductor having the same potential as the innermost winding conductor of the disc-shaped coil is wound one turn inside the winding conductor of the disc-shaped coil in the radial direction. Since the disk-shaped winding is constituted by the above, the following effects can be obtained.

1) The insulation distance is reduced by alleviating the electric field concentration at the curvature of the corner of the winding conductor.

2) The coil height decreases.

3) Since the size of the coil is reduced, the size of the device is reduced, and the cost can be reduced.

4) The insulation reliability is improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a disc-shaped winding according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a main part of a disc-shaped winding according to a third embodiment of the present invention.

FIG. 4 is a comparison diagram of the electric field at the coil end of the disc-shaped winding of the conventional stationary induction device and the electric field at the coil end of the disc-shaped winding of the stationary induction device of the present invention. FIG. 3B is a state diagram of an electric field at a coil end of a disc-shaped winding of the stationary induction device of FIG.

FIG. 5 is a sectional view of a disk-shaped winding of a conventional stationary induction device.

FIG. 6 is a cross-sectional view of a main part in the vicinity of a disk coil of a disk winding of a conventional stationary induction device.

FIG. 7 is an enlarged cross-sectional view of a main part in the vicinity of a disk coil of a disk winding of a conventional stationary induction device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Discoid winding 2 ... Discoid coil 3 ... Winding conductor 4 ... Insulation coating 5 ... Radial duct piece 6 ... Radial cooling duct piece 7 ... Vertical duct piece 8 ... Vertical cooling duct piece 9 ... Shield Conductor 10: Mold resin a: Width dimension of shield conductor b: Width dimension of rectangular wire of winding conductor c: Width dimension of winding conductor including insulating coating.

Claims (4)

[Claims] 1. A plurality of disc-shaped coils wound with a winding conductor are stacked in the axial direction and connected in series, and radial duct pieces between the disc-shaped coils are radially arranged on the circumference. To form a radial cooling duct piece, a vertical duct piece is disposed in a cutout provided at the inner end or both ends of the radial duct piece, and the radial duct piece is formed into a circular coil. In a stationary induction device having a disk-shaped winding formed by forming a vertical cooling duct while being equally distributed and fixed on the circumference, a disk-shaped winding is formed inside the winding conductor of the disk-shaped coil in the radial direction. A stationary induction machine characterized in that a disk-shaped winding is formed by winding a shield conductor having the same potential as the innermost winding conductor of a coil for one turn. 2. The stationary induction machine according to claim 1, wherein the relationship between the width b of the winding conductor and the width a of the shield conductor in the direction of the winding axis is a <b. 3. A method according to claim 1, wherein the periphery of the shield conductor is insulated with a molding resin, and the width of the molding resin in the winding axis direction is equal to the width of the winding conductor in the winding axis direction after insulation. Or the static induction device according to 2. 4. The relationship between the width b of the winding conductor in the direction of the winding axis and the width a of the shield conductor is as follows: when a = b, the curvature of the corner of the shield conductor on the inner surface side of the coil is determined by the following equation. The stationary guidance device according to claim 1, wherein the curvature is larger than a curvature of the stationary guidance device.