JPH09246064A - Dry transformer winding, its manufacture and dry transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability, by forming a wire by covering and warping conductor and first insulating paper with second insulating paper, forming a coil wherein the wire is wound, and so making the cover that the lamination direction of the coil is thicker than the width direction of the coil. SOLUTION: A continuous paper is used for a first insulating paper 2a, and three sides of rectangular conductor 1 are wrapped in a U-shape. On the first insulating paper 2a, the continuous paper is also used for a second insulating paper 2b, and the opposite three sides of the first insulating paper 2a are wrapped in a U-shape. A wire is wound in a cylindrical coil shape with a winding machine, and winding is formed. The insulating cover thickness α1 of a coil lamination direction (y) is made greater then the insulating cover thickness α2 of a coil width direction (x), where α1 :α2 =1:2 is held. Prepreg insulating material is used for material of an insulating paper used for covering conductor. Thereby productivity can be improved, and energy and material can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry transformer winding wire, an improved dry transformer winding using the wire, a manufacturing method thereof, and a dry transformer using the winding. It is a thing.

[0002]

2. Description of the Related Art Dry transformer windings are fixed by impregnating the windings with resin in order to improve insulation, moisture resistance and dust resistance, and to insulate the windings from each other and the winding surface. Had to do. The conventional dry type transformer winding is actually developed.
This will be described with reference to Japanese Patent Laid-Open No. 620. The coil conductor according to the above described technique has a structure as shown in FIG. FIG.
FIG. 6 is a schematic explanatory view of a conventional dry transformer winding. As shown in the figure, an outer-layer insulation is formed by forming an insulation-coated electric wire composed of a conductor 1 having a strand insulation 2 on the outer peripheral surface thereof, and adhering to at least one side surface of the insulation-coated electric wire along the length direction of the conductor 1. 4 and interlayer insulating paper 5 are provided to form a laminated winding, and a method of impregnating the laminated winding with a resin is adopted.

[0003]

In the process of manufacturing the dry type transformer winding in the above-mentioned prior art, time and manpower are required for the work of inserting the interlayer insulating paper and the work of impregnating the resin, which causes a problem in productivity. It was The object of the present invention is to solve the above problems in the prior art. Firstly, the workability in manufacturing a dry transformer is improved, and the dry transformer winding excellent in productivity is provided. Secondly, a method for manufacturing a dry type transformer winding in which the insulation thickness varies depending on the direction easily and surely,
Thirdly, it is to provide a dry type transformer using a winding that does not cause a defective portion due to a defective portion of the interlayer paper.

[0004]

To achieve the above object,
The structure of the dry type transformer winding according to the first invention is such that the first insulating paper is wrapped in a U-shape with respect to the conductor cross section, and the second insulating paper is inverted U-shape with respect to the conductor cross section from above. Form a wire by covering the conductor and the first insulating paper from the opposite side of the first insulating paper to form a wire, and form a winding by winding the wire in a tubular coil shape, It is characterized in that the coating is thicker in the laminating direction than in the width direction of the winding. In the dry transformer winding described in the preceding paragraph, the coating is formed of a prepreg insulating material. In the dry transformer winding according to any one of the preceding paragraphs, a third insulating material is provided inside the coating to adjust the coating thickness in the width direction and the stacking direction of the winding. It is characterized by. In the dry transformer winding according to any one of the preceding paragraphs, when the conductors are arranged in diagonal positions, an insulating material is reinforced at the corners of the conductors. .

In order to achieve the above object, a dry transformer winding manufacturing method according to a second aspect of the present invention is configured so that a bare wire conductor is supplied, and a first insulating paper is provided from a side surface of the supplied conductor. Supplying a second insulating paper, the conductor and the first insulating paper,
According to the feeding direction of the second insulating paper, the first insulating paper is made to follow the U-shape on the conductor, and then the first insulating paper is made to follow the U-shape on the conductor. Forming a wire by covering the second insulating paper from the opposite side of the U-shaped body of the first insulating paper along the inverted U-shape, winding the wire, and forming a winding. It is characterized by.

In order to achieve the above object, the dry transformer according to the third aspect of the present invention is a dry transformer in which a winding in which an insulated wire is wound around a tubular coil is laminated and molded in a plurality of stages.
A dry-type transformer, wherein the dry-type transformer winding according to any one of claims 1 to 4 is used for the winding.

[0007]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. [Embodiment 1] FIG. 1 is a sectional view of a wire used in a dry transformer winding according to an embodiment of the present invention. As shown in the figure, continuous paper is used as the first insulating paper 2a, the three sides of the rectangular conductor 1 are wrapped in a U shape, and continuous paper is used as the second insulating paper 2b from above. The opposite three sides of the insulating paper 2a of No. 1 are included in a U-shape. In this way, by winding the first and second insulating papers around the conductor and enclosing them, the insulating paper coating thicknesses differ in the direction of the conductor 1. Now, if the longitudinal direction of the illustrated conductor is the x direction and the lateral direction is the y direction, the coating thickness differs between the x direction and the y direction. That is, the ratio α of the insulating coating thickness in the x direction and the y direction
It becomes ₁ : α ₂ = 1: 2. When forming such a wire in a wire winding machine, the lowest layer is started from one end and finished at the other end, and then stacked and stacked to form the next layer. To do. This procedure is repeated until the outermost layer is formed. Therefore, the width direction of the winding is from the one end to the other end, and the stacking direction of the steps is the layer direction. If the coil width direction is the x direction and the coil stacking direction is the y direction, the insulating coating thickness in the y direction becomes thicker than the insulating coating thickness in the x direction, and the above α ₁ : α ₂ = 1: 2,
It is not necessary to insert an interlayer paper which requires complicated labor, and insulation between layers can be provided only by the conductor coating.

FIG. 2 is a cross-sectional view of an essential part of a winding formed by winding the strand of FIG. In FIG. 2, the material of the insulating paper used for the conductor coating is polyamide (PA), polyethylene naphthalate (PEN), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyethylene terephthalate (PE).
Insulating materials having a low dielectric constant such as T) and prepreg insulating material may be used.

Further, in FIG. 2, when the potential difference due to the electromotive force of the transformer in the illustrated portion is ΔV1 and ΔV2, the insulating coating thickness α _{1 in} the coil width direction and the insulating coating thickness α _{2 in the} coil stacking direction are shown. Is the shared potential ΔV1, in each direction.
It preferably corresponds to the ratio of ΔV2. In FIG. 1 of [Embodiment 1], α ₁ : α ₂ = 1: 2, and the thickness of the insulating paper can be made unnecessarily large especially in the coil width direction.

[Second Embodiment] Another embodiment of the present invention will be described with reference to FIGS. 3 is a cross-sectional view of a wire used in a dry transformer winding according to another embodiment of the present invention, and FIG. 4 is a wire used in a dry transformer winding according to another embodiment of the present invention. FIG. FIG. 3 shows a wire in which an insulating paper 2C (thickness β) is included on one side of the conductor 1 in the coil stacking direction. FIG. 4 shows the insulating paper 2C (thickness β
/ 2) is arranged on both sides of the conductor. If such an element wire is used, the insulating paper 2a (thickness γ) having different thicknesses
And 2b (thickness γ) and the insulating paper 2C (thickness β or β / 2) can be used for any ratio of the shared potential difference in the stacking direction and the width direction.
A dry transformer winding can be formed by winding the wire shown in FIGS. 3 and 4 by a winding machine.

[Embodiment 3] Still another embodiment of the present invention will be described with reference to FIG. [Embodiment
1], the conductors 1a and 1b are arranged between the layers and diagonally, so that the insulating paper thickness on the diagonal line between the lines may be thin. FIG. 5 is a cross-sectional view of a wire used in a dry transformer winding according to still another embodiment of the present invention. In FIG. 5, the insulating paper 2a and the insulating paper 2b that are continuous at the corners of the conductor 1 are extended and wound,
If the inclusion is ensured, the thickness of the insulating paper on the diagonal line between the wires can be secured, and the insulation performance of the wires can be improved.
A winding can be made by using this wire and winding it by a winding machine.

[Fourth Embodiment] Still another embodiment of the present invention will be described with reference to FIG. FIG. 6 is a cross-sectional view of wires of a dry type transformer winding according to still another embodiment of the present invention. In FIG. 6, the case where the wire is wound edgewise is shown. The short side of the wire 1 is doubly wrapped with a continuous insulating paper 2a and a continuous insulating paper 2b. In this way, the insulation performance of the wire can also be improved, and a winding can be made using this wire.

[Embodiment 5] Still another embodiment of the present invention will be described with reference to FIG. FIG. 7 is a schematic explanatory diagram of a dry transformer winding manufacturing method according to still another embodiment of the present invention. As shown in the figure, it comprises a conductor supplying step 6, a coating attaching step 7, and a winding step 8. In the conductor supplying step 6, the conductor 1 is a copper or aluminum wire and is supplied in a bare wire state. In the covering attaching step 7, since the insulating papers 2a and 2b are sequentially arranged in a U shape from the side surface of the supplied conductor 1, the covering attaching jigs j ₁ and j ₂ are installed on both sides of the conductor 1, respectively. Has been done. These jigs j ₁ and j ₂ cause the insulating papers 2 a and 2 b pulled out from the roll-shaped paper body to follow the conductor 1, so that the insulating paper 2
According to the feeding directions of a and 2b, for example, one side has an opening and the other three sides have a U-shape, and the cross-sectional area thereof is gradually narrowed. This jig j
_{By 1} , the insulating paper 2a is made to follow the U-shape from the side surface of the conductor 1. Then, the jig j _2, on the insulating paper 2a which this along a U-shaped conductor 1, insulating coating from the opposite side in the U-shape and along the insulating paper 2b reversed U-shape To form a winding. Next, in a winding step 8, the roll body 8 is wound. If the roll body 8 is a coil winding machine, the coil winding can be performed as it is.

[Embodiment 6] Still another embodiment of the present invention will be described with reference to FIG. FIG. 8 is a schematic explanatory view of a dry type transformer winding according to still another embodiment of the present invention. FIG. 8 is a diagram showing a fixing method using a prepreg material having a self-bonding property, particularly as a conductor coating in a dry transformer winding. The prepreg material is a fiber reinforced material impregnated with resin and is an uncured or semi-cured material.Using this property, the uncured resin that adheres flows out when heated, and the gaps between the prepreg materials are created. Although they are buried and fixed, the pressure between them is applied from the outside to further narrow the gaps between the prepregs and further firmly bond them.

Generally, when a rectangular coil is wound, a force acts in a radial direction at a coil corner portion, that is, a bent portion,
External force is generated and the adhesiveness of the prepreg is good, but the straight part cannot be expected to be fixed by external force. Therefore, as shown in FIG. 8, after winding the coil, the winding coil 9 is wound with a shrinkable tube 10 filled with a liquid at the outermost periphery, and heated to cure the prepreg material and prevent the tube 10 from being wound. The adhesiveness of the prepreg material can be improved by applying pressure to the winding coil 9 due to the expansion of the filled liquid. In this way, it is possible to form a dry transformer winding with improved adhesion of the prepreg material.

[Embodiment 7] Still another embodiment of the present invention will be described with reference to FIG. FIG. 9 is a schematic explanatory view of a dry type transformer according to still another embodiment of the present invention. FIG. 9 is an external view of a transformer with tap changeover using windings according to an embodiment of the present invention. As shown in the figure, in the transformer T with tap changeover, the winding coil 9 is placed on the pedestal 12 according to the number of phases (three phases in the figure), the tap changer 13 is attached thereto, and the tightening pedestal 14 is used for tightening. ing. A terminal 15 is attached to the tightening frame 14. The winding coil 9 is
Since the resin casting work such as a resin after the winding is finished is omitted and the winding is fixed by self-fusion, the striped portion 11 is formed in the circumferential direction of the winding coil 9. Is. In this way, a dry type transformer can be obtained in which no defective layer is generated.

As described above, according to the present invention, in this way, the insulating layer corresponding to the interlayer insulating paper is provided with the insulating coating on the conductor, and a part of the coating is formed of the prepreg insulating material. The wires can be fixed to each other and the winding surface only by heat treatment after winding the insulated conductor. As a result, it is possible to manufacture an inexpensive coil by abolishing the interlayer insulating paper of the laminated winding and abolishing the resin casting work after the winding to reduce the material cost and the energy cost.

[0018]

As described above, according to the structure of the dry type transformer winding according to the present invention, the work of inserting the interlayer insulating paper and the work of impregnating the resin can be omitted, and the productivity can be improved and the energy consumption can be improved. This has the effect of reducing the amount of materials used. Also, by using a prepreg insulating material,
Since the wires are fixed to each other and the winding surface by heat treatment, it is possible to provide a dry transformer winding and a dry transformer having excellent insulation and moisture resistance.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a wire used in a dry transformer winding according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a main portion of a winding formed by winding the strand of FIG.

FIG. 3 is a cross-sectional view of a wire used in a dry transformer winding according to another embodiment of the present invention.

FIG. 4 is a cross-sectional view of a wire used in a dry transformer winding according to still another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a wire used in a dry transformer winding according to still another embodiment of the present invention.

FIG. 6 is a cross-sectional view of a wire used in a dry transformer winding according to still another embodiment of the present invention.

FIG. 7 is a schematic explanatory view of a dry transformer winding manufacturing method according to still another embodiment of the present invention.

FIG. 8 is a schematic explanatory view of a dry type transformer winding according to still another embodiment of the present invention.

FIG. 9 is a schematic explanatory view of a dry type transformer according to still another embodiment of the present invention.

FIG. 10 is a schematic explanatory view of a conventional dry transformer winding.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Conductor, 2 ... Elemental wire insulation coating, 2a ... C-shaped elemental wire insulation coating (inside), 2b ... C-shaped elemental wire insulation coating, 2c ... Elemental wire insulation reinforcement coating, 3 ... Winding inner circumference insulation layer 4 ... Winding outer peripheral insulating layer, 5 ... Interlayer insulating paper, 6 ... Conductor supply section, 7 ... Cover mounting section, 8 ... Conductor winding section, 9 ... Winding coil, 10 ... Tube, 11 ... Coil stripe section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Shimizu 7-1-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Koki Taneda Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa No. 292 Co., Ltd. Production Engineering Research Laboratory, Hitachi, Ltd.

Claims (6)

[Claims] 1. A first insulating paper is wrapped in a U-shape with respect to a conductor cross section, and a second insulating paper is inverted from the top in a U-shape with respect to the conductor cross section, and is opposite to the first insulating paper. From the above to cover the conductor and the first insulating paper to form an elemental wire, and to form a winding in which the elemental wire is wound into a tubular coil shape, and the coating is laminated in the width direction of the winding. Dry type transformer winding characterized by thickening the direction. 2. The dry transformer winding according to claim 1, wherein the coating is made of a prepreg insulating material. 3. The dry transformer winding according to claim 1, wherein a third insulating material is provided inside the coating to cover the winding in a width direction and a stacking direction. A dry transformer winding characterized in that the thickness is adjusted. 4. The dry transformer winding according to claim 1, wherein when the conductors are arranged in diagonal positions, an insulating material is reinforced with respect to the corners of the conductors. Dry type transformer winding characterized by doing so. 5. A bare wire conductor is supplied, and a first insulating paper and a second insulating paper are supplied from a side surface of the supplied conductor, and the conductor and the first insulating paper and the second insulating paper are supplied. According to the paper feeding direction, the first insulating paper is made to follow the U-shape on the conductor, and then the second insulating paper is placed on the conductor which is made to follow the first insulating paper in the U-shape. A dry type transformer characterized in that a wire is formed by covering the first insulating paper from the side opposite to the U-shaped body along the inverted U-shape to form a wire, and winding the wire. Method for manufacturing coil winding. 6. A dry-type transformer in which a winding obtained by winding an insulated wire around a cylindrical coil is laminated in a plurality of stages, wherein the winding has the dry-type transformer winding according to any one of claims 1 to 4. A dry-type transformer characterized by using wires.