JPS60207326A - Manufacture of resin molded coil - Google Patents

Abstract

PURPOSE:To check generation of unimpregnated voids in the inside of a coil when the multiplex winding coil is to be impegnated with resin by a method wherein resin is made to be impregnated sufficiently to the inside of the coil from the place of a wavy insulator interposed between the layers at least on one side of the conductor winding round layers. CONSTITUTION:At a multiplex winding coil 8, cooling medium passages are formed in the axial direction between the respective conductor winding round layers according to a wavy insulator 6 provided between the respective conductor winding round layers and edge part insulators 3, 3'. Accordingly, when the multiplex winding coil 8 is to be impregnated with resin, because resin enters in the respective conductor winding round layers passing the respective cooling medium passages formed by the respective wavy insulators 6, and impregnated sufficiently up to the inside of the insulating films of conductors 4, no void is generated. Moreover, a hardening promotor is adhered to the corrugated insulators 2, 6, the lower edge part insulator 3' and an outside peripheral insulator 7, and the insulating film 5 of the conductor 4, and by making the resin impregnated to the whole of the multiplex winding coil 8 at resin impregnating time to gel, leakage of resin can be checked.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing resin molded coils used in high voltage, large capacity molded dry transformers, reactors, and the like.

[Technical background of the invention and its problems]

In the field of dry type transformers, there are molded dry type transformers that use resin molded coils that are impregnated and hardened with resin to improve insulation properties. The resin molded coil used in this molded dry type transformer is generally constructed by arranging a resin-molded primary coil and secondary coil concentrically around an iron core leg.

However, there are two main methods for manufacturing resin molded coils: those that use a mold and those that do not.
The method of manufacturing resin molded coils without using a mold is increasing because it has advantages in terms of productivity and economy, such as diversification of specifications and maintenance of molds. One method that does not use this mold is to attach a curing accelerator to the insulating layer in advance and react with the resin to form the insulating layer.This method has the advantage of simplifying the resin processing process. .

When manufacturing a resin molded coil using this method, first, a plurality of conductor winding layers each formed by winding a conductor are wound concentrically around an insulating tube with an interlayer insulator interposed between the layers.
A multi-wound coil is formed by providing end insulators at the upper and lower ends of each conductor-wound layer and by providing an outer peripheral insulator at the outermost periphery of the conductor-wound layer. A curing accelerator is applied to the lower end insulator, the outer circumferential insulator, and, if necessary, the interlayer insulator in this multi-wound coil. Then, this multi-wound coil is placed in a resin bath and impregnated with resin, and when the impregnated resin reacts with the curing accelerator and becomes glued, the multi-wound coil is taken out, and then the impregnated resin is heated and cured to form a resin molded coil. Manufacture.

However, in this method of manufacturing resin molded coils, a sheet-like insulator such as non-woven fabric is usually used as an interlayer insulator, and this sheet-like insulator is placed between each conductor-wound layer without any gaps between the conductor-wound layers. They are placed close together. For this reason, when impregnating the assembled multi-wound coil with resin, the resin cannot pass between the layers of each conductor winding layer and satisfactorily impregnate the inside of the coil, resulting in unimpregnated voids inside the coil, and the corona generated voltage However, if the breakdown voltage is low, the quality of the coil may be impaired.

[Purpose of the invention]

The present invention addresses these problems and provides a method for manufacturing a resin molded coil with a multi-wound structure that has excellent impregnability and good quality.

[Summary of the invention]

The method for manufacturing a resin molded coil according to the present invention involves arranging a plurality of conductor winding layers concentrically, each of which is a conductor wound with an insulating material coated with an insulating material with good resin impregnation, and forming upper and lower ends of each conductor winding layer. An end insulator made of a material with good resin impregnation property is provided on the outside, and an outer periphery P made of a material with good resin impregnation property is provided on the outer periphery of the outermost conductor winding layer! , a rim is provided, and a wavy insulator is provided between layers located at least on one side of the conductor-wound layer to form a multi-wound coil, and an insulating coating of the conductor in the multi-wound coil and a bottom end insulation A curing accelerator is attached to the object and the corrugated insulator, respectively.
Thereafter, the multi-wound coil is impregnated with a resin in a resin bath, and when the impregnated resin reacts with the curing accelerator and becomes dull, the multi-wound coil is taken out from the resin bath and the impregnated resin is heated and cured. This is a characteristic feature. That is,
When impregnating a multi-wound coil with resin, the resin is sufficiently impregnated into the coil from the part of the wavy insulator interposed between layers on at least one side of the conductor-wound layer, so that unimpregnated male ids are generated inside the coil. It is designed to prevent this from happening.

[Embodiments of the invention]

Embodiments of the present invention illustrated in the drawings will be described below.

1 to 3 show one embodiment of the present invention, and in this embodiment, a case will be explained in which a multi-turn coil used as a high voltage coil is manufactured.

FIGS. 1 and 2 are a plan view and a sectional view of a multi-turn coil. In the figure, U indicates the start of the conductor winding, ■ indicates the end of the conductor winding, and T□ to T6 are tap terminals. Further, each wave-like insulator is provided with a wadding 9 over the entire circumferential direction of the coil, but only a portion thereof is shown in FIG. First, a wavy insulating material 2 for main insulation is arranged around the entire circumference of an insulating cylinder 1 made of epoxy glass or the like so that the waves are continuous in the circumferential direction.

The axial length of this corrugated insulator 2 is almost the same as the axial length of the insulating cylinder 1. Next, the conductor 4 is wound in a cylindrical shape a predetermined number of times around the outer periphery of the corrugated insulator 2, excluding both ends in the axial direction, to form a first conductor winding layer. This conductor 4 is coated with an insulating coating 5 made of an insulating material that is easily impregnated with resin, such as aramid nonwoven fabric.

Next, wrap an insulating material with good resin impregnation properties, such as FRP, some heat-resistant material, asbestos, rock wool, etc., on the outside of the upper and lower ends of the first conductor winding layer, and then wrap it with adhesive tape, glass tape, etc. Fix the end insulator 3.
form y. The axial lengths of these end insulators 3° 3' and the conductor winding layer are almost the same as the axial lengths of the wavy insulators 2. Subsequently, a wavy insulator 6 as an interlayer insulator is wound and fixed around the entire circumference of the first conductor winding layer and the end insulators 3, 3' in the same manner as the wavy insulator 2. Then, the conductor 4 is wound in a cylindrical shape around the outer periphery of this wavy insulator 6 in the same manner as the first layer to form a second conductor winding layer, and the top and bottom ends of this conductor winding layer are End insulator 3
．． 3' and secure it.

A wavy insulator 6 is placed in the area where the conductor 4 crosses from the first layer to the second layer.
There is a notch in the middle. Thereafter, in the same manner, the wavy insulator 6, the conductor winding layer, and the end insulators 3, 3' are sequentially formed up to the sixth layer. Thereafter, a multi-wound coil 8 is constructed by winding a non-woven fabric tape or glass tube with good resin impregnation as an outer circumferential insulator 7 around the outer periphery of the sixth conductor winding layer and the end insulators 3, 3'. The tag terminals T1 to T extending from the outer circumferential surface are connected to the conductor 4 at a predetermined number of turns and drawn out to the outside. In the embodiment of the present invention, the wavy insulators 2, 6, the insulating coating 5 of the conductor 4, the end insulator 3' at the lower end and the outer insulator 7 contain an imidazole-based curing accelerator as a curing accelerator, for example. IB2MZ (hardening accelerator manufactured by Shikoku Kasei, trade name) is applied in advance. The curing accelerator was applied by diluting 1B2MZ with ethyl alcohol at a ratio of 10:90, impregnating the insulator in the solution, and then evaporating the solvent. Further, if necessary, a curing accelerator may also be applied to the end insulator 3 at the upper end.

Next, after pre-drying this multi-wound coil 8, it is set in a resin tank 9 as shown in FIG.
In the chamber, 1 part of the impregnating resin is impregnated under vacuum and pressure. The multi-wound coil 8 is left in this state, and the hardening accelerator attached to each insulator reacts with the impregnated resin 11 to form a glue, and the impregnated resin 1
1 stops leaking from the multi-wound coil 8, the multi-wound coil 8 is taken up from the resin tank 9.

Thereafter, the multi-wound coil 8 is heated in a heating furnace or the like to harden the resin 11 impregnated into the multi-wound coil 8.

In this example, as the impregnating resin 1, TVB-2 was used as the main ingredient.
703A liquid (manufactured by Toshiba Chemical, trade name) and B as a hardening agent.
-570 (manufactured by Dainippon Ink, product name) respectively, and 7
It was impregnated at a resin temperature of 0 to 90°C and left for 1 to 2 hours to obtain an integral resin molded coil.

According to this manufacturing method, the wavy insulator 6 is provided between each conductor winding layer and the end insulator 3, 3' in the multi-wound coil 8, and the wavy insulator 6 is Cooling medium passages are formed in the axial direction between the conductor turns. This passage is formed in the space between the wavy portion of the wavy insulator 6 and the peripheral wall of the conductor-wound layer, and when the coil is assembled as a transformer, air acts as a cooling medium to cool the coil. . On the other hand, when the multi-wound coil 8 is impregnated with resin, the resin 11 enters each conductor-wound layer through each cooling medium passage formed by each wave-like insulator 6, forming each conductor-wound layer. The insulating coating 5 of the conductor 4 is impregnated. Therefore, the resin 11 is sufficiently impregnated into the multi-wound coil 8, so that no unimpregnated gates occur inside the coil. In addition, in addition to the wavy insulators 2 and 6, the lower end insulator 3', and the outer insulator 7, the curing accelerator is also applied to the insulation coating 5 of the conductor 4, so that the entire multi-wound coil 8 is coated with the resin. The impregnated resin does not aggregate and the resin impregnated into the conductor winding layer does not leak out from the cooling medium passage of the corrugated insulator 6.

Moreover, when this resin-molded coil is used, a cooling medium passage is formed between the conductor-wound layers through the corrugated insulator 6, so that heat dissipation from the conductor 4 is performed well and the cooling effect is improved.

In particular, the corrugated insulator 2.6 can easily maintain the dimensions of the cooling medium passage portion at equal intervals, and at the same time, it becomes a solid insulating layer after being impregnated with resin and cured, so it prevents the movement of electric charge in the void portion, resulting in a breakdown voltage. can be improved. In experiments conducted by the inventor, a coil composed of wavy insulators 2 and 6 with a pitch of 13 m had an impact breakdown voltage of 95 kV or more, indicating that the wavy insulators 2 and 6 had an effect of 10 - as an insulating purrier. Understood. On the other hand, in response to the electromagnetic force in the axial direction during a short circuit, the conductor winding layers are all solidified with resin in the axial direction and are integrated, so the vertical electromagnetic force in the axial direction is canceled out within the coil. Therefore, the force that comes out in the axial direction is only the unbalanced force, and virtually no force comes out in the axial direction. Furthermore, when a short circuit occurs, electromagnetic force is also generated in the radial direction, but the corrugated insulators 2 and 6 and the conductor-wound layer are bonded with resin, and each conductor in the conductor-wound layer is also bonded with resin. This makes it strong, so it won't break. This simplifies the support of the coil.

In this example, the multi-wound coil was manufactured by attaching the curing accelerator to the insulating material in advance, but after the multi-wound coil was formed, the curing accelerator was applied to the insulating material part of the coil by impregnation, etc. Good too. Although we have explained the structure in which the conductor is wound with one wire, it is also possible to wind the conductor with two or more wires (9 turns).

Next, other embodiments shown in FIGS. 4 and 5 will be described.

The same parts as in FIGS. 1 and 2 are given the same reference numerals. In this embodiment, two conductor-wound layers are continuously wound, and the corrugated insulators 2 and 6 are positioned only on one side of the conductor-wound layer. A sheet-like interlayer insulator 13 made of, for example, aramid non-woven fabric with good resin impregnation properties is interposed between the two conductor-wound layers, and the inner conductor-wound layer and the outer conductor-wound layer are separated by a transition portion 12. Continuous. Incidentally, since the outermost conductor-wound layer is easily impregnated with resin through the outer-periphery insulator 7, it is not necessarily necessary to interpose a wavy insulator on one side of this conductor-wound layer.

In this embodiment as well, the resin can be sufficiently impregnated into the multi-wound coil through the corrugated insulators 2 and 6 on one side of the conductor-wound layer.

Although the embodiments described so far have described multi-wound coils used for high-voltage coils, multi-wound coils used for low-voltage coils can also be manufactured in the same manner.

In the case of a multi-turn coil used for a low-voltage coil, the conductor is wound directly around the insulating cylinder without using a corrugated insulator for the main gap. Furthermore, when manufacturing a high-voltage coil, it is not necessary to provide a corrugated insulator for the main gap, and it may be provided separately.

Furthermore, instead of manufacturing and assembling the high-voltage coil and the low-voltage coil separately, the low-voltage coil and the high-voltage coil may be formed by continuously winding them concentrically.

〔Effect of the invention〕

As explained above, according to the method for manufacturing a resin molded coil according to the present invention, when a resin molded coil is manufactured by coating an insulator with a curing accelerator, the inside of the coil can be sufficiently impregnated with resin, A high quality resin molded coil with good insulation properties can be obtained.

[Brief explanation of the drawing]

1 to 3 each show an embodiment of the manufacturing method of the present invention, and FIGS. 1 and 2 are a cross-sectional view and a vertical cross-sectional view showing a resin molded coil, respectively, and FIG. 3 is a coil FIG. 4 and FIG. 5 are a cross-sectional view and a vertical cross-sectional view showing a resin molded coil of another example 13-. 1... Insulating tube, 2... Wavy insulator for main insulation, 3゜3
'... End insulator, 4... Conductor, 5... Insulating coating of conductor, 6... Corrugated insulator for interlayer insulation, 7... Perimeter insulator・ Applicant's representative Patent attorney Suzu Takehiko E 14- El+ Figure 4 Figure 3

Claims (1)

[Claims] A plurality of conductor winding layers are arranged concentrically in which a conductor coated with an insulating material with good resin impregnation property is wound into a cylindrical shape, and an insulating material with good resin impregnation property is placed on the outside of the top and bottom ends of each conductor winding layer. At the same time, an outer insulator made of an insulating material with good resin impregnation is provided on the outer periphery of the outermost conductor-wound layer, and an outer insulator made of an insulating material with good resin impregnation is provided on the outer periphery of the outermost conductor-wound layer. ni, state insulation i deception 1 ke, many! At the same time, a curing accelerator is applied to the insulating coating of the conductor, the lower end insulator, and the wavy insulator in this multi-wound coil, and then the multi-wound coil is impregnated with resin in a resin bath. A method for manufacturing a resin-molded coil, comprising: carrying out the above steps, and taking out the multi-wound coil from the resin tank when the impregnated resin reacts with the curing accelerator and becomes dull, and heating and curing the impregnated resin.