JPS62211907A - Double layer herical winding - Google Patents

Abstract

PURPOSE:To facilitate a winding operation by improving a space factor of a winding by winding an outside helical winding directly on an inside helical winding. CONSTITUTION:Plural spacers 61 of winding axial direction are arranged uniformly on a periphery of a basic insulating cylinder 71 and an inside helical winding 2 is wound while inserting a predetermined number of spacers 51 of radial-direction in the spacers 61. On the periphery of the inside winding 2, axial-direction spacers 8 for an outside helical winding are uniformly arranged and an outside helical winding 3 is wound from a winding-finish end of the inside winding 2 while inserting the spacers formed by attaching radial-direction spacers 81 to a sheet insulator 82. As a result, a basic insulating cylinder for an outside winding, which has been necessary in a conventional part, becomes unnecessary and it improves a apace factor. Because the radial-direction spacers 51 and 81 can be attached separatedly, the inside winding and the outside winding can be wound continuously and a connecting operation is needless. The number of the axial-direction spacers 8 can be determined according to a compression stress at a time of short of the windings, thereby improving a resistance to compression stress.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a two-layer helical winding in which low-voltage windings are arranged concentrically and connected in series at one end of the windings. It is related to the structure of

(Prior art) Generally, in transformers, helical windings are used at relatively low voltage.
The current flowing through this helium winding, which is often used in the case of large currents, increases with the capacity of the transformer, reaching from several thousand amperes to several thousand amperes.

When such a large current flows, if the lead wire of the helical winding is crawled inside the transformer tank to the transformer bushing terminal, the magnetic field created by the large current flowing through the lead wire may overheat the tank wall or damage the tank wall. There were delays that caused non-negligible stray losses.

Therefore, one of the countermeasures is to use conventional low-voltage helical windings.
The inner helical winding 2 and the outer helical winding 3 are arranged concentrically on the core leg 1 as shown in Fig. 2, and the lower ends of the windings are connected in series to form a two-layer helical winding. The opening is only at the top edge.

With this structure of two-layer helical winding, it is possible to omit the need to run the lead wire from the bottom end of the helical winding inside the tank.
The lead wire can be wound only between the upper end of the helical winding and the bushing terminal.

(Problems to be Solved by the Invention) However, the two-layer helical winding is effective in preventing local overheating of the tank wall due to the magnetic field of the large current lead wire and reducing stray loss.
This method has disadvantages such as a deterioration in the space factor of the winding and inefficient winding work.

That is, the inner helical winding 2 and the outer helical winding 3 have winding conductors wound with inclinations in different directions and key spacers 51, 52 of the radial spacing pieces, as shown in FIGS. 3 and 4, respectively. Since the axial positions of the inner helical coil 2 are not necessarily the same,
and the outer helical coil 3 is published in Japanese Patent Publication No. 54-1
As shown in 37623, separately manufactured items were combined.

In other words, as shown in FIG.
Winding wire 2 is wound evenly distributed. A predetermined number of key spacers 51 are inserted while being attached to the rail 61 during winding.

After fabricating the outer helical winding in the same way, attach the axial spacing piece duct piece 8 to the cut groove on the outside of the key spacer of the inner helical winding, and insert the outer helical winding 3 concentrically with the inner helical winding 3. However, it was necessary to connect the helical coils to each other outside the windings to form a two-layer helical coil. Furthermore, it is difficult to make the basic insulating cylinders 71 and 72 thin in order to ensure the roundness of the windings, and the rails 61 and 72 are difficult to make thin.
62 is difficult to reduce below a predetermined size due to the mounting structure of the key spacers 51 and 52 and measures to cool the windings. Therefore, the required insulation strength of the low-voltage helical winding is small,
There is no need to increase the gap with the inner helical winding, which results in an unnecessarily large structure, and the winding dimensions are large.
This has the disadvantage that the space factor of the windings in the space deteriorates.

In addition, the rails 61 and 62 and the dust piece 8 also function as supports to suppress the compressive stress generated in the winding due to the radial mechanical force when the winding is short-circuited. If the number of support points has to be increased, the number of key spacers 51 and 52 attached to the rails 61 and 62 will also increase. However, as the number of support points for the key spacer increases, it becomes impossible to secure a sufficient number of horizontal winding coolers.

Therefore, the number of support points for rails 61 and 62 is not restricted.
Instead, it was necessary to make the winding wire itself highly hard.

The present invention was made in view of the above circumstances, and its purpose is to provide a two-layer series helical winding that can improve the space factor of the winding and facilitate the winding work. It is in.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a key spacer group in which radial spacer key spacers for outer helical windings are bonded on an insulating sheet. The present invention is characterized in that the outer helical winding is directly wound around the inner helical winding by arranging a plurality of axially spaced duct pieces evenly around the outer periphery of the inner winding.

(Function) Since the outer helical winding can be directly wound on the outside of the inner helical winding via the winding direction spacing piece, the basic insulation cylinder and rail that were conventionally required can be omitted. The dimensions of the helical winding and the outer helical winding can be reduced to the required dimensions for winding cooling and electrical insulation.

(Example) An example of the present invention shown in the drawings will be described below. FIG. 1 shows a concentric double helical winding arrangement according to the invention. The inner helical winding 2 is constructed by distributing a plurality of winding axial spacing pieces 61 equally around the outer periphery of a basic insulating cylinder 71, as in the conventional case, and sandwiching a predetermined number of radial spacing piece key spacers 51 attached to the rail 61. Wind. On the outer periphery of the inner helical winding, six outer helical winding spacer duct pieces 8 are equally distributed, and the number of them is selected and arranged in accordance with the radial compressive stress applied when the winding is short-circuited.

The outer helical winding 3 is wound in the same direction from the winding end of the inner helical winding 2, and at the same time, a group of spacing pieces to which the outer helical winding radial spacing pieces 81 are attached is inserted into the sheet-like insulator 82. Wind in the direction of the winding axis on the opposite side.

With a two-layer helical winding having such a configuration, the outer helical winding 3 can be directly wound outside the inner helical winding 2 via the winding axial spacing piece 8, which was previously necessary. Since the basic insulation tube and rail can be omitted,
The dimensions of the inner helical winding and the outer helical winding can be reduced to the required dimensions for winding cooling and electrical insulation.

Furthermore, since the outer helical winding does not have a basic insulating cylinder and the radial spacing pieces 8 attached to the key spacer 51 and the sheet-like insulator 82 can be attached independently, the outer helical winding has no basic insulating cylinder. It is possible to wind the wire continuously without cutting it.

Since it is not necessary for the axial spacing pieces 8 to have the same number as the inner helical winding and the outer helical winding,
The number of support points can be selected depending on the compressive stress applied when the winding is short-circuited, and the compressive stress resistance can be improved.

〔Effect of the invention〕

As explained above, according to the present invention, the outer helical winding can be directly wound outside the inner helical winding via the winding axial spacer duct piece, so the gap between the windings can be reduced, and the transformer The overall dimensions can be reduced.

Furthermore, since the outer helical winding can be continuously wound without being cut from the inner helical winding, winding connection work can be omitted.

In addition, since the equal number of duct pieces can be selected independently from the equal number of radially spaced pieces of the inner helical winding and outer helical winding, the number of support points can be adjusted according to the compressive stress applied to the winding when the winding is short-circuited. As a result, it is possible to obtain the effect of "improving compressive stress resistance."

[Brief explanation of drawings]

FIG. 1 is an upper external view of a low voltage winding according to the present invention, FIG. 2 is a wiring diagram showing an embodiment of a transformer in which the low voltage winding is a two-layer helical winding, and FIGS. 3 and 4 are FIG. 5, a winding configuration diagram of a two-layer helical winding, is an upper plan view of a conventional low-voltage winding. 1. Iron core. 2...Low voltage inner helical winding, 3...Low voltage outer helical winding, 4...High voltage winding, 8.61.62...Axial spacing shaft, 51, 52...Radial spacing piece, 71, 72...Basic insulation cylinder. Agent Patent Attorney Noriyuki Chika Yudo Hirofumi MitsumataFigure 1Figure 2Figure 5

Claims (1)

[Claims] A group of wires in which a plurality of parallel conductors are arranged in a rectangular cross-section is spirally wound so as to form a radially continuous cooler with a plurality of radially spaced pieces interposed therebetween. Two layers of helical windings are arranged concentrically, the inner helical winding and the outer helical winding are electrically connected in series at one end of the winding, and the lead of the winding is connected at one end. In the two-layer helical winding, the radial spacing pieces for the outer helical winding are bonded radially to a thin insulating sheet having an inner diameter approximately equal to the inner diameter of the outer helical winding. A two-layer helical winding characterized in that the two-layer helical winding is structured in groups and a plurality of axially spaced pieces are equally arranged around the outer periphery of the inner helical winding.