JP2012142518A - Multiple cylindrical winding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multiple cylindrical winding capable of reducing the size while ensuring a dielectric voltage.SOLUTION: A multiple cylindrical winding comprises: a cylindrical winding layer in which cylindrical windings are wound around in a coaxial cylindrical manner so as to be located in a plurality of layers; and a plurality of insulating spacers 121 and 122 which are located between the layers in the cylindrical winding layer, and each of which has a length substantially equal to a width of the cylindrical winding layer in an axial direction of the cylindrical winding layer. At least one of the spacers, which are located between a first winding layer including an input-side line end 160 on a side where electricity is input to the cylindrical windings and a second winding layer adjacent to the first winding layer among the cylindrical winding layer, includes a portion made of polypropylene.

Description

  The present invention relates to a multi-cylindrical winding, and more particularly to an oil-insulated multi-cylindrical winding.

  The multi-cylindrical winding is formed by winding an insulation-coated coil conductor in a cylindrical shape over a plurality of layers via a vertical rectangular vertical spacer on an insulating cylinder. The cylindrical windings located in the adjacent cylindrical winding layers are connected in series as a whole by alternately repeating connection at the upper end or the lower end in the axial direction of the cylindrical winding layers.

  In a multi-cylindrical winding in a conventional transformer, a high potential difference may occur between adjacent cylindrical winding layers. Patent Documents 1 and 2 are prior art documents disclosing a multi-cylindrical winding capable of ensuring an insulation distance in such a case. In the multiple cylindrical windings described in Patent Documents 1 and 2, the vertical oil passage between the layers is enlarged at the axial end of the cylindrical winding layer where a high electric field is generated.

JP-A-2-254706 Sho 63-204606

  When a surge with a short rise time such as a lightning impulse enters the line end of the multiple cylindrical winding, a high potential difference is generated between the cylindrical winding layers adjacent to the line end. In order to withstand the voltage generated at the time of surge intrusion such as lightning impulse, a method of increasing the insulation distance between the cylindrical winding layers adjacent to the line end, or close to the line end A method of providing an insulating member at the end of the cylindrical winding layer has been adopted. In this case, the overall size of the multiple cylindrical winding increases.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a multi-cylindrical winding which can be miniaturized while ensuring withstand voltage.

  The multiple cylindrical winding based on this invention is a multiple cylindrical winding used by being immersed in insulating oil. A multi-cylinder winding is a cylindrical winding layer in which a cylindrical winding is wound in a coaxial cylindrical shape and positioned in a plurality of layers, and a cylinder in the axial direction of the cylindrical winding layer that is positioned between the cylindrical winding layers. And a plurality of insulating spacers having substantially the same length as the width of the winding layer. The cylindrical winding layer is located between the first winding layer including the input-side line end on the side where electricity is input to the cylindrical winding and the second winding layer adjacent to the first winding layer. At least one of the plurality of spacers includes a portion formed of polypropylene.

  According to the present invention, it is possible to reduce the size of the multiple cylindrical winding while ensuring the withstand voltage.

It is a perspective view which shows the structure of the multiple cylindrical winding which concerns on Embodiment 1 of this invention. It is the figure which looked at the multiple cylindrical winding of FIG. 1 from the arrow II direction. It is the figure which looked at the multiple cylindrical winding of FIG. 1 from the III-III line arrow direction. It is sectional drawing which shows a part of 1st winding layer and 2nd winding layer of the multiple cylindrical winding of the embodiment. It is a top view which shows a state in case a part of spacer has a chip. It is sectional drawing which shows a part of 1st winding layer and 2nd winding layer in the multiple cylindrical winding which concerns on Embodiment 2 of this invention. It is sectional drawing which shows the structure of an experiment example. It is a graph which shows the result of an example of an experiment, and the vertical axis shows creepage breakdown voltage and the horizontal axis shows the kind of spacer.

  Hereinafter, the multiple cylindrical winding according to Embodiment 1 of the present invention will be described with reference to the drawings. In the following description of the embodiments, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a perspective view showing the configuration of a multiple cylindrical winding according to Embodiment 1 of the present invention. FIG. 2 is a view of the multiple cylindrical winding of FIG. 1 as viewed from the direction of arrow II. FIG. 3 is a view of the multiple cylindrical winding of FIG. 1 as viewed from the direction of arrows III-III.

  As shown in FIGS. 1 to 3, a multiple cylindrical winding 100 according to the present embodiment includes a cylindrical winding layer 130 in which a cylindrical winding is wound in a coaxial cylindrical shape and is positioned in a plurality of layers, and a cylindrical winding layer. And a plurality of insulating spacers 120 having a length substantially equal to the width of the cylindrical winding layer 130 in the axial direction of the cylindrical winding.

  In the present embodiment, the cylindrical winding layer 130 includes a first winding layer 131, a second winding layer 132, a third winding layer 133, a fourth winding layer 134, and a fifth winding layer 135 in order from the inside. And a sixth winding layer 136. However, the number of layers of the cylindrical winding layer 130 is not limited to six, and may be a plurality of layers.

  The first winding layer 131 includes an input-side line end 160 on the side where electricity is input to the cylindrical winding. Specifically, the input side line end 160 is drawn from the position of the upper end of the first winding layer 131. The sixth winding layer 136 includes an output side line end 161 on the side where electricity is output from the cylindrical winding. Specifically, the output side line end 161 is drawn from the position of the upper end of the sixth winding layer 136. An insulating cylinder 110 is provided inside the first winding layer 131.

  A spacer 120 having a vertically long rectangular shape is disposed between the cylindrical winding layers 130. Of the spacers 120, only the spacers 122 disposed between at least the first winding layer 131 and the second winding layer 132 are made of polypropylene. In the present embodiment, eight spacers 122 are disposed, but it is sufficient that at least one spacer 122 is disposed.

  Among the spacers 120, the spacers 121 arranged between other layers are made of insulating paper. A spacer 123 made of insulating paper is disposed between the insulating cylinder 110 and the first winding layer 131. Examples of the insulating paper include a press board.

  As shown in FIG. 2, the multiple cylindrical winding 100 is used by being immersed in an insulating oil 150. The space between the cylindrical winding layers 130 is filled with an insulating oil 150.

  In the present embodiment, as shown in FIG. 3, the cylindrical winding layer 130 is connected via connection portions that are alternately located on one end side or the other end side in the axial direction of the cylindrical winding between the layers. Are connected in series.

  Specifically, in the first winding layer 131, the cylindrical windings are arranged in order from the cylindrical winding 131 </ b> A connected to the input-side line end 160 to the lowermost cylindrical winding 131 </ b> Z in order in the lower direction in the drawing. It is wound around. In the second winding layer 132, the cylindrical winding is wound around the spacer 122 from the cylindrical winding 132A located at the lowermost end to the uppermost cylindrical winding 132Z in order upward.

  In this way, the cylindrical winding layer 130 is configured by winding the cylindrical winding from the first winding layer 131 to the sixth winding layer 136 alternately around the spacer 120 in each layer.

  In the cylindrical winding layer 130, the cylindrical windings positioned at the upper end or the lower end of the layers adjacent to each other are electrically connected by a connecting portion made of a conductive member. Specifically, the cylindrical winding 131 </ b> Z located in the first winding layer 131 and the cylindrical winding 132 </ b> A located in the second winding layer 132 are connected via the connection portion 170. The other cylindrical windings between the respective layers are also connected via the connecting portion 170.

Hereinafter, the voltage generated between the layers of the cylindrical winding layer 130 will be described.
FIG. 4 is a cross-sectional view showing a part of the first winding layer and the second winding layer of the multiple cylindrical winding of the present embodiment. FIG. 5 is a top view showing a state where a part of the spacer has a chip.

  As shown in FIG. 4, the cylindrical winding has a structure in which the insulating paper 139 covers the periphery of the copper wire 138. As described above, since the cylindrical winding 131Z and the cylindrical winding 132A are connected by the connecting portion 170, there is no potential difference between the cylindrical winding 131Z and the cylindrical winding 132A. On the other hand, since the cylindrical winding 131A and the cylindrical winding 132Z are not connected, a potential difference V is generated between the cylindrical winding 131A and the cylindrical winding 132Z.

  The potential difference V is applied to the spacer 122 located between the layers. Therefore, the spacer 122 needs to have a withstand voltage that can withstand the potential difference V.

  Lightning impulse may act on the multiple cylindrical winding 1. When a lightning impulse is applied to the input side line end 160, the potential difference V between the cylindrical winding 131A and the cylindrical winding 132Z located closest to the input side line end 160 becomes a high voltage. Therefore, if an insulating paper is used for the spacer 122, it is necessary to secure an insulating distance by increasing the thickness d of the spacer 122. Alternatively, it is necessary to dispose an insulating member where the potential difference V is generated. In such a case, it becomes an obstacle to miniaturization of the multi-cylindrical winding 100, and the structure becomes complicated and the device cost increases.

  In this embodiment, since the spacer 122 is made of polypropylene having a dielectric strength higher than that of insulating paper, the thickness d of the spacer 122 is reduced while maintaining a dielectric strength voltage that can withstand a high voltage potential difference V due to factors such as lightning impulse. Can do. As a result, the multiple cylindrical winding 1 can be downsized.

  As shown in FIG. 5, if the spacer 122 is chipped, a minute oil gap 151 is formed between the spacer 122 and the first winding layer 131. When the spacer 122 is formed of insulating paper, since the dielectric constant of the insulating oil 150 and the insulating paper is about 1: 2, when the high voltage V is applied to the spacer 122, the electric field E in the minute oil gap 151 is It may be higher than the surrounding insulating oil 150 and the insulation may be broken locally.

  Since the dielectric constant of polypropylene is substantially the same as that of the insulating oil 150, it is possible to prevent the electric field E generated in the minute oil gap 151 from being increased. In this embodiment, since the spacer 122 made of polypropylene is used, the insulation performance of the spacer 120 can be improved, and the reliability of the multiple cylindrical winding 1 can be improved.

Hereinafter, the multiple cylindrical winding according to the second embodiment of the present invention will be described.
(Embodiment 2)
The present embodiment is different from the first embodiment only in that a part of the spacer formed of polypropylene is made of insulating paper, and therefore, description of other configurations will not be repeated.

  FIG. 6 is a cross-sectional view showing a part of the first winding layer and the second winding layer in the multiple cylindrical winding according to the second embodiment of the present invention.

  The potential difference generated between the cylindrical winding located in the first winding layer and the cylindrical winding layer located in the second winding layer is caused by the cylindrical winding 131A and the cylindrical winding 132Z connected to the input line end. Between the cylindrical winding 131 </ b> Z and the cylindrical winding 132 </ b> A becomes zero.

  Therefore, in the present embodiment, only the portion 122a having a high potential difference between layers uses polypropylene, and the other portions 121a are formed of insulating paper with spacers. In other words, the spacer is formed of insulating paper on the connection portion 170 side in the axial direction of the cylindrical winding layer 130, and is formed of polypropylene on the opposite side to the connection portion 170 side. Note that the polypropylene and the insulating paper are bonded together with an adhesive having resistance to oil.

  By doing in this way, the amount of polypropylene used can be reduced and the device cost can be further reduced while maintaining the dielectric strength using polypropylene only in the portion where high insulation pressure is required.

  In the present embodiment, the potential difference generated between the cylindrical winding located in the first winding layer and the cylindrical winding located in the second winding layer facing each other is opposed to the cylindrical winding. 10% of the potential difference generated between the cylindrical winding 131A located in the first winding layer and the cylindrical winding 132Z located in the second winding layer closest to the input-side line end 160 in the axial direction of the layer 130 The above portions are made of polypropylene, and the other portions are made of insulating paper. With this configuration, it is possible to reduce the cost of the spacer while maintaining the insulating pressure by the spacer. Note that it is sufficient that at least one spacer made of polypropylene and insulating paper is disposed.

  Hereinafter, a comparative experiment example in the case of using press board or polypropylene as the material of the spacer will be described.

(Experimental example)
FIG. 7 is a cross-sectional view showing the configuration of this experimental example. FIG. 8 is a graph showing the results of this experimental example, where the vertical axis indicates the creeping breakdown voltage and the horizontal axis indicates the type of spacer.

  As shown in FIG. 7, in this experimental example, the insulating oil 150 was immersed in a state in which the spacer 192 was disposed between the winding 190 and the winding 191 in which the copper wire 138 was covered with the insulating paper 139. Two types of spacers, one formed from a press board and one formed from polypropylene, were prepared.

  With one of the two types of spacers arranged, a voltage was applied between the winding 190 and the winding 191 to measure the creepage breakdown voltage. As shown in FIG. 8, in the average value of the experimental results, the creepage breakdown voltage of the spacer formed using polypropylene was about 10% higher than that of the spacer formed using the press board.

  From this result, it was proved that the insulating performance can be improved by about 10% by using the spacer made of polypropylene.

  In addition, the said embodiment disclosed this time is an illustration in all the points, Comprising: It does not become a basis of limited interpretation. Therefore, the technical scope of the present invention is not interpreted only by the above-described embodiments, but is defined based on the description of the scope of claims. Further, all modifications within the meaning and scope equivalent to the scope of the claims are included.

  1,100 Multiple cylindrical winding, 110 Insulating cylinder, 120, 121, 122, 123, 192 Spacer, 130 Cylindrical winding layer, 131 First winding layer, 131A, 131Z, 132A, 132Z Cylindrical winding, 132 2nd Winding layer, 133 Third winding layer, 134 Fourth winding layer, 135 Fifth winding layer, 136 Sixth winding layer, 138 Copper wire, 139 Insulating paper, 150 Insulating oil, 151 Micro oil gap part, 160 input side line end, 161 output side line end, 170 connection part, 190,191 windings.

Claims (3)

A multi-cylinder winding used by being immersed in insulating oil,
A cylindrical winding layer in which the cylindrical winding is wound in a coaxial cylindrical shape and located in a plurality of layers;
A plurality of insulating spacers positioned between the cylindrical winding layers and having substantially the same length as the width of the cylindrical winding layer in the axial direction of the cylindrical winding layer;
With
Among the cylindrical winding layers, between the first winding layer including the input side line end on the side where electricity is input to the cylindrical winding and the second winding layer adjacent to the first winding layer. A multi-cylindrical winding comprising a portion in which at least one of the plurality of spacers located is formed of polypropylene. The cylindrical winding layers are connected in series by being connected via connecting portions alternately positioned on one end side or the other end side in the axial direction of the cylindrical winding layer between the layers,
2. The at least one spacer according to claim 1, wherein in the axial direction of the cylindrical winding layer, the connection portion side is formed of insulating paper, and the side opposite to the connection portion side is formed of polypropylene. Multiple cylindrical winding as described.   In the at least one spacer, a potential difference generated between the cylindrical winding located in the first winding layer and the cylindrical winding located in the second winding layer facing each other is opposed to each other. And between the cylindrical winding located in the first winding layer and the cylindrical winding located in the second winding layer closest to the input-side line end in the axial direction of the cylindrical winding layer. The multi-cylindrical winding according to claim 2, wherein the multi-cylindrical winding is formed of polypropylene in a portion that is 10% or more of the potential difference generated in the other portion and formed of insulating paper in the other portion.

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