JPS59153449A - Manufacture of coil for rotary electric machine - Google Patents

Abstract

PURPOSE:To accelerate the hardening of resin and to prevent the leakage of the resin by disposing a non-woven fabric immersed with resin curing catalyst before coating a main insulating layer at least at both side faces of a coil conductor unit. CONSTITUTION:Strand conductors 1 coated with strand insulators 2 are wound in quintuple in the depthwise direction of a slot and adjacently in two rows in the circumferential direction. Then, a non-woven fabric tape 12 immersed in advance by suitably means such as coating, spraying or dipping a resin curing catalyst is lap wound at the end over the entire periphery of the unit 5 and the axial length of a core slot 4. Then, after the base material of a main insulating layer 6 is coated, for example, on the periphery of the non-woven fabric 12 by taping, a semiconductor layer 11 is coated on the outer peripheral surface to form coil units 7A, 7B. The units 7A, 7B are inserted into the slot 4 of the core 3, a wedge 9 is hitted, further filled in a resin tank and resin is then immersed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a method for manufacturing a single-unit coil, in particular, a coil conductor unit is formed by winding strand conductors with strand insulation in a layered manner in the depth direction of an iron core slot. The present invention relates to a method of manufacturing a rotating electric machine coil.

FIG. 1 is a sectional view showing a coil of a conventional rotating electrical machine.
In FIG. 1, (1) is a strand conductor provided with strand insulation (2), which is wound in layers in the depth direction of the slot (4) of the iron core (3). It is molded as a knit (5). (6) is this coil conductor unit (
5) The main insulating layer applied around the resin impregnated 710
The upper coil conductor unit (5
) constitutes a coil unit. (7A) is an upper coil unit, (7B) is a lower coil unit, and a seven-wheel motor (8) is interposed between both coil units (7A) and (7B). (9) is both the above-mentioned coil units (7A).

(7B) is a wedge that fixes and holds the iron core slot (4).

In Figure 1, the voltage applied between each turn of the strand conductor (1) is borne by the strand insulation (2), and the voltage applied between the strand conductor (1) and the iron core (3) is borne by the strand insulation (2). The insulation (2) and the main insulation layer (6) share this responsibility.

By the way, wire insulation (2) is generally thin, so when applying bare wire insulation (2), care must be taken to avoid pinholes etc. At the same time, wind the wire conductor (1) with the single wire insulation (2) or the wire conductor (1) by an appropriate number of turns so that it has an appropriate cross-sectional shape (-1, where 1 is the shape) as shown in Figure @1. @
When threading, I am very careful not to touch the wire feeder A (2). In addition, the main insulating layer (6) generally relies on resin insulation in most cases, and cracks and voids may occur due to the type of tM resin, heating temperature, lJl, I heat curing time, etc. At present, various efforts and research have been made to prevent this, and the dielectric strength, insulation properties, etc.
Checks are made by measuring , insulation resistance, capacitance meter, partial discharge voltage, etc.

The insulation properties of the wire insulation (2) and the main insulation layer (6) are as follows: Efforts are being made and researched.

The purpose of this invention is to improve the insulation properties from a different perspective from the conventionally known ones, namely, to improve the insulating material itself, and to devise heating temperatures and heating times. Rather than adding a coil structure, we are developing a coil structure that has not been considered in the past, especially a coil conductor unit formed by winding wire conductors with wire insulation in a layered manner in the depth direction of the slot in the iron core. The present invention aims to satisfy the above object by focusing on the structure of a coil conductor unit having a main insulating layer provided around the coil conductor unit.

FIG. 2 is an enlarged view for explaining the basic idea and point of view of this invention.

That is, when looking at the wire conductor (1) on which the wire wire insulation (2) has been applied, the corner of the wire conductor (1) has a radius, and the wire insulation (2) is applied thereon. Because of this, bare wire insulation (2
) When the strand conductor (1) coated with
As shown in the figure, a groove (10) is inevitably formed at the boundary between the wire conductors (1) of each turn.

Since a full (10) is formed in this way, if the main insulating layer (6) is formed from resin gold such as epoxy resin, what is the difference in terms of results? There is a high possibility that a void will be formed in the part i'+7 (10). The coil is once completely impregnated with resin by vacuum pressure impregnation, but in areas with large spaces like 11 (10), during heat curing, the impregnated resin may flow out due to a decrease in viscosity before curing. , a void is created here.

In this case, the fact that there is no resin in the groove (10) and it remains as a void means that, for example, corona discharge may occur in the groove (10).
0) causes deterioration of -C insulation, i.e., failure of main insulation layer (6) and wire insulation (2) 8: Causes deterioration, prolongs life, /1... derogation of form, etc. This contributes to making it difficult.

Since the wire conductors (1) are arranged in multiple layers within the slots (4), there are more grooves (1,0) on both sides of the coil conductor unit (5) than on the top and bottom sides. Moreover, when taping the main phase of the main insulating layer (6), such as mica tape, the tape on both sides of the coil conductor unit (5) is more likely to lift from these surfaces than on the bottom surface, potentially creating a large void. Because of the large size, the gap between the voids is particularly
It is large in i-possible.

In the past, research efforts have focused exclusively on improving the resin itself, improving the heating temperature and time, etc. 1. Innovating the treatment of the insulating material itself, and research efforts.

As mentioned earlier, the present invention aims to improve the insulation properties, and it is different from the conventionally known methods, namely, improvement of the insulating material itself, heating temperature, [
Because we can put some effort into processing the so-called insulating material itself, such as time (in particular, the coil structure, which has not been considered in the past,
A coil conductor unit is formed by winding the underline conductor with wire insulation in layers in the depth direction of the slot of the iron core, and around this coil conductor unit (this main insulating layer is impregnated with resin and IJII heat cured). The present invention aims to provide a concrete means for eliminating or suppressing the adverse effect on the insulation properties of the grooves formed between the respective tension conductors in a rotating electric machine formed by the following methods.

FIG. 3 is a longitudinal section showing the main parts of an embodiment of the present invention.
'i leap (cross-sectional view taken in the direction of 1 angle with respect to the axis of rotation 4ζII). The wire conductor (6) is formed in the coil conductor unit (5) by winding it in the depth direction of the slot (4) of the iron core (3), that is, in the radial direction. This is the main insulating layer applied around the conductor unit (5) and is formed by resin impregnation and heat curing. (7A) is -1-
Coil unit (7B) (lower coil unit, picture coil unit (7A).

(7B) is housed in the -l-l-roslot), and a separator (8) is interposed between both coil units (7'A) and (7B). (9) is a wedge that securely holds both the coil units (7A), (7B) and the separator (8) in the core slot (4), and (10) is the element to which the tension break R (2) is applied. Grooves formed between the wire conductors (1), (1]) a semi-conducting layer applied over the main insulating layer (6) to suppress external discharge, and (12) a non-woven fabric formed into the coil conductor unit (5). This layer is formed by taping the entire outer circumference of the

Next, a method of manufacturing the coil portion shown in FIG. 3 will be explained. First, the bare wire conductors (1), which have been given the necessary tension insulation (2) such as by taping with insulating tape, are arranged in five layers in the depth direction of the slot and in two adjacent rows in the circumferential direction. Wind. These five layers and two rows of windings are of course the capacity of the rotating electric machine,
This is just an example for securing the required number of coil turns and coil cross-sectional area, and may be changed as necessary. After this, a nonwoven fabric tape of an appropriate thickness pre-impregnated with a resin curing catalyst by an appropriate means such as coating, spraying, dipping, etc. is applied around the entire circumference of the coil conductor unit (5) and along the axial length of the core slot (4). Wrap the ends once over the length. Next, the base material of the main insulating layer (6), such as mica tape, is taped, etc., to form the nonwoven fabric (12).
After that, a semiconducting layer (11) is applied to the outer peripheral surface of the coil unit (7A) and (7B). These coil units (7A).

(7B) first inserts the coil unit (7B) into the slot (4) of the iron core (3), then the separator (
8) and then insert the coil unit (7A). When the wedge (9) is driven in, the coil units (7A) and (7B) are fixed in the slot (4). Then, they are all The resin is placed in a resin M (not shown). When placed in a resin bath, the resin permeates into the base material and nonwoven fabric, and when the permeation is complete, it is pulled out of the resin bath at an appropriate time and heated for a predetermined period of time. and harden.

No spaces remain in the grooves (10) in the coil formed in this way.

After checking the insulation properties with respect to tan δ, the product according to the present invention had the properties shown in curve A of FIG. 4. Curve B in the figure is the characteristic of the conventional device shown in FIG. As is clear from this claw figure 4, the insulation properties were improved according to the present invention. The vertical axis in Figure 4 is tanδ (%
), the horizontal axis shows the voltage, and U on the horizontal axis is the rated voltage.

The reason why there are no voids in the grooves (10) as described above is that N1o) is filled by the conformation of the nonwoven fabric, and the resin curing catalyst impregnated into the nonwoven fabric causes curing during the polymerization and curing process after resin impregnation. This is thought to be because the speed is increased and leakage of the impregnated resin is prevented. In the above example, an epoxy resin (Araldite GY 255, acid anhydride curing agent HN-5500 with benzyldimethylamine 0.3 PHR added) was used as the impregnating resin, and Epicoat 1001 and zinc octylate were used as the resin curing catalyst. A solution (10% concentration) dissolved in a mixed solvent of acetone and trol was used. The entire nonwoven fabric was impregnated with the resin curing catalyst and then air-dried. A polyester nonwoven fabric was used as the nonwoven fabric.

In the above example, the resin curing catalyst is pre-impregnated into the nonwoven fabric (12) before applying the nonwoven fabric (12) around the coil conductor unit (5).
The non-woven fabric (12) may be impregnated with the non-woven fabric (12). Further, in the above embodiment, the nonwoven fabric (12) is wound around the entire outer circumference of the coil conductor unit (5), but as mentioned earlier, the problem of voids is large on both sides of the coil conductor unit (5), so Although it is most preferable to apply the nonwoven fabric to the entire outer periphery of the coil conductor unit (5), it is also possible to apply the nonwoven fabric only to both sides, and it is clear that the insulation properties are significantly improved in that case as well. If the nonwoven fabric is applied only to both sides of the coil conductor unit (5), the nonwoven fabric can be attached to both sides. In addition, in the above embodiment, a non-woven tape is used and the ends are wrapped once, but
A sheet-like product may be rolled into a sushi roll.

Furthermore, although a polyester nonwoven fabric was used as the nonwoven fabric, similar effects can be obtained by using a polyamide nonwoven fabric (for example, "Nomex", a trade name of EI DuPont) or cellulose.

Further, in the above embodiment, the resin impregnation method is used.

Although the full impregnation method has been described, a resin impregnation press hardening method or a resin rich method may also be adopted. Furthermore, if necessary, a nonlinear electric field mitigation paint is applied in the coil end direction (outward in the axial direction of the slot) so as to overlap the semiconductive layer (11) at the end of the straight part of the coil conductor unit (5). It may be inserted into the slot (4) after that.

As described above, in this invention, the nonwoven fabric impregnated with a resin curing catalyst is arranged on at least both sides of the coil conductor unit (5) before applying the main insulating layer, so that the nonwoven fabric fits into the grooves. Since the heather is filled in and the curing of the resin is accelerated by the resin curing catalyst to prevent leakage, no voids remain in the grooves, resulting in the effect of improving insulation properties.

[Brief explanation of drawings]

Figure 1 is a vertical side view showing the coil section of a conventional rotating electric machine.
Fig. 2 is an enlarged vertical side view for explaining the basic idea and points of focus of this invention, Fig. 3 is a longitudinal side view showing the main part of an embodiment of this invention, and Fig. 4 is a conventional FIG. 3 is a diagram comparing and showing tan δ-voltage characteristics of a coil and a coil of an embodiment of the present invention. In the figure, (1) is the wire conductor, (2) is the bare wire insulation, and (3
) is an iron core, (4) is a slot, and (5) is a coil conductor unit. In FIGS. 1 to 3, the same reference numerals indicate the same or equivalent parts. Agent Patent Attorney Shin Kuzuno - Figure 3 JP-A-59-153449 (5) @ Figure 4 Voltage

Claims (1)

[Claims] 1. After forming a coil conductor unit by winding wire conductors with wire insulation in layers in the depth direction of the core slot, at least both sides of the coil conductor unit are formed. A non-woven fabric is applied over the axial length of the core slot, a resin curing catalyst is applied to this non-woven fabric before or after that, a main insulating layer base material is applied around it, and the resin impregnated in this main insulating layer base material is applied. A method for manufacturing a rotating electric machine coil, which is characterized by heating and curing. 2. The method for manufacturing a rotating electric machine coil according to claim 1, wherein the resin curing catalyst is impregnated into the nonwoven fabric by coating, spraying, or dipping.