JP4249431B2 - Insulating coil for rotating electrical machine and method for manufacturing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of an insulating coil used as an armature coil of a rotating electric machine such as a generator and an electric motor, particularly a high-voltage rotating electric machine.
[0002]
[Prior art]
In order to increase the insulation of a high-voltage insulating coil for a rotating electrical machine, it is important to remove the air gap from the inside of the insulator as much as possible.
[0003]
As shown in FIG. 5, the conventional normal high-voltage insulated coil is formed by winding and aligning the insulated wires 11 of the coil and then press-molding them at a high temperature to produce the wire coil 1. A ground insulating layer not impregnated with an insulating resin is formed by winding a ground insulating tape such as a laminated mica tape around the wire coil 1 a plurality of times. Next, the wire coil 1 on which the ground insulating layer not impregnated with the insulating resin is formed is placed in a resin-impregnating mold, and the thermosetting insulating resin 22 is impregnated by vacuum and pressure to be cured. Form. This method is often used for manufacturing a coil of a large-sized rotating electrical machine, and is impregnated in units of coils, so that it is called a single coil impregnation method.
[0004]
Alternatively, an unimpregnated wire coil is inserted into the slot of the core of the rotating electrical machine, and after installing the interlayer, wedge, etc., the core and coil are integrally impregnated with an insulating resin and cured, and then fully impregnated. There is also a method called.
[0005]
In any type of insulating coil, in order to obtain a ground insulating layer having no voids inside, improvement of an impregnation technique with an insulating resin has been attempted. As a result, the current ground insulating layer is at a level where a good impregnation state almost completely free of voids can be obtained.
[0006]
[Problems to be solved by the invention]
As the insulation technology has improved in recent years, the size of the rotating electrical machine has been reduced by reducing the coil size by reducing the thickness of the coil insulation layer while keeping the coil conductor dimensions of the insulated coil unchanged. There is a growing demand for
[0007]
However, in the conventional insulation coil in which the ground insulation layer of the insulation coil is composed of laminated mica tape and impregnated resin, if the insulation layer thickness is simply reduced for miniaturization, the insulation layer has a higher electric field. For this reason, there is a disadvantage that the dielectric breakdown strength is reduced and the life of the insulating coil is shortened.
[0008]
The present invention provides a high voltage insulation coil for a rotating electrical machine that has a high dielectric breakdown resistance and can extend the life even when the thickness of the ground insulating layer is thin, in order to reduce the size of the rotating electrical machine. It is the purpose.
[0009]
[Means for Solving the Problems]
In order to achieve such a problem, the present invention provides a nonporous film-like insulating material having a high electric field strength as a base material on the outer periphery of a wire coil formed by winding an insulated wire on a conductor. It was formed by winding a prepreg laminated mica tape containing a semi-cured thermosetting resin on the laminated mica tape, heating and press-molding , and curing the semi-cured thermosetting resin . A ground insulating layer is formed from a first insulating layer and a second insulating layer formed by winding a porous tape-shaped insulating material around the outer periphery of the first insulating layer and then impregnating and curing the thermosetting resin. It is formed.
[0010]
In addition, an internal electric field relaxation layer may be provided inside the first insulating layer in the ground insulating layer. The internal electric field relaxation layer is formed of a conductive tape and a semi-cured thermosetting resin on the insulating tape. It can comprise with the conductive prepreg tape comprised between the prepreg tapes which apply | coated .
[0011]
Furthermore, the corner portion of the ground insulating layer can be arc-shaped to perform electric field concentration relaxation processing.
[0012]
Furthermore, the insulation coil for a rotating electrical machine is formed by assembling a non-porous film-like insulating material having a high electric field strength around the outer periphery of a wire coil formed by winding an insulated wire on a conductor. A prepreg assembled mica tape made of mica tape containing a semi-cured thermosetting resin is wound, heated and pressure-molded, and the semi-cured thermosetting resin is cured to form a first insulating layer. And a step of winding a porous tape-shaped insulating material around the outer periphery of the first insulating layer, impregnating and curing the thermosetting resin, and forming a second insulating layer.
[0013]
In the case of providing an internal electric field relaxation layer, in the step of forming the first insulating layer, heat the wire coil by winding a conductive prepreg tape under the prepreg mica tape, pressure forming.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to examples shown in the drawings.
[0015]
Example 1
FIG. 1 shows a first embodiment of the present invention.
[0016]
In this figure, reference numeral 1 denotes a strand coil formed by winding a strand 10 formed by applying strand insulation 12 to a strand conductor 11 using a winding form. A ground insulating layer 2 composed of a high electric field insulating layer 21 and an impregnated resin insulating layer 22 including a ground insulating tape is formed on the outer periphery of the wire coil 1. Reference numeral 13 denotes a head stuffing made of an insulating material that fills a void in the head of the wire coil 1.
[0017]
The high electric field insulation layer 21 is a semi-cured thermoset of a B stage on at least one surface of a laminated mica tape or sheet formed by collecting mica using a nonporous high electric field insulation film as a base material. Resin, for example. It consists of a prepreg laminated mica tape or sheet formed by applying an epoxy resin or a polyimide resin. The insulating layer 21 is formed by winding the prepreg laminated mica tape or sheet on the wire coil 1 and press-molding the whole while heating at a high temperature with a high-temperature press-molding press. Thus, resistance to high electric field insulating film and the mica nonporous is bonded to the outer periphery of the wire coil 1 without generating voids, resistance to high electric field insulating layer 21 without gap is formed.
[0018]
A laminated mica tape formed by collecting mica on a porous tape base material made of glass fiber or the like on the high electric field insulating layer 21 is wound as a ground insulating tape, and epoxy resin or polyimide resin is used. The ground insulating layer 2 is formed by impregnating the thermosetting resin with a vacuum and pressurizing and curing. The ground insulating tape used here is preferably a tape made of a porous insulating material as a base material in order to improve the impregnation property of the thermosetting resin.
[0019]
The insulating coil for a rotating electrical machine thus formed is a high-field-resistant nonporous film-based mica tape having a high dielectric breakdown voltage per thickness as a high-field-resistant insulating layer 21 of the ground insulating layer 2. By using this, high insulation performance can be obtained, so that the thickness of the ground insulating layer 2 can be reduced, and the dimensions of the insulating coil can be reduced.
[0020]
A laminated mica tape based on a nonporous insulating film has high dielectric breakdown voltage characteristics, but since it has a poor impregnation property with an insulating resin, if it is used as it is, the insulating layer formed by impregnating the resin As shown in the present invention, a prepreg assembly formed by applying a semi-cured insulating resin to the nonporous insulating film substrate in advance as in the present invention cannot be obtained. By using the mica tape, the prepreg resin of this tape can form an adhesive layer having no gap with respect to the wire coil, so that high insulation performance can be obtained.
[0021]
-Example 2-
FIG. 2 shows a second embodiment of the present invention.
[0022]
In FIGS. 2A and 2B, reference numerals 1 and 2 denote a wire coil and a ground insulating layer, respectively, as in the first embodiment. In this practical example, an internal electric field relaxation layer 3 is provided between the wire coil 1 and the high electric field insulating layer 21. This internal electric field relaxation layer 3 is made of B-stage (semi-cured) epoxy with conductive tape 31 formed by weaving conductive fibers such as carbon fibers in an organic or inorganic insulating fiber base material, and insulating tape from above and below. It is formed by being wound on a wire coil 1 and sandwiched between prepreg tapes 32 and 33 treated with a thermosetting resin such as a resin based on polyimide, a resin based on polyimide, and a high electric field insulation layer 21 is further formed thereon. A porous film base material prepreg aggregated mica tape is wound and pressure-molded while being heated by a thermoforming press, and these tapes are bonded without voids. Further, a ground insulating tape made of a laminated mica tape of a porous fiber base material is wound thereon, and then a thermosetting insulating resin is impregnated by vacuum and pressure, and the resin is heated and cured to finish the ground insulating layer. . Since the relationship between the insulating layers is not clear in FIG. 2A, the portion B in FIG. 2A is enlarged and shown in FIG.
[0023]
As a result, since a conductive layer for electric field relaxation is provided near the surface of the wire coil, the uneven electric field distribution on the outer periphery of the wire coil 1 is relaxed, so that local electric field concentration is eliminated and the ground insulating layer 2 as a whole. Will share the electric field almost equally. For this reason, even if the thickness of the ground insulating layer 2 is reduced, the insulating performance can be maintained, and the size of the insulating coil can be reduced.
[0024]
Example 3
FIG. 3 shows a third embodiment of the present invention. The insulating coil of the third embodiment has substantially the same configuration as the insulating coil of the second embodiment, but the difference is the configuration of the internal electric field relaxation layer 3. . That is, in Example 2, the internal electric field relaxation layer 3 is formed by the conductive tape 31 and the upper and lower prepreg tapes 32 and 33. In this Example 3, the details are shown in FIG. As shown, the internal electric field relaxation layer 3 is formed by a conductive prepreg tape 34 and a lower prepreg tape 32.
[0025]
The conductive prepreg tape 34 is obtained by applying a B-stage (semi-cured) thermosetting epoxy resin or polyimide resin to a conductive tape or sheet.
[0026]
Thereby, since the thickness of the internal electric field relaxation layer 3 can be reduced, the insulation coil can be made smaller.
[0027]
—Example 4—
FIG. 4 shows a fourth embodiment of the present invention.
[0028]
The internal configuration of the insulating coil of the fourth embodiment is the same as that of each of the embodiments described above, except that the curvature of the arc of the corner of the wire pad head stuffing 13 is increased so that the outer circumference of the insulation coil is grounded. This is that the corners of the insulating layer 2 are arcs having a large curvature, and the corners are subjected to electric field distribution relaxation processing.
[0029]
According to the configuration of the fourth embodiment, the electric field concentration in the corners inside and outside the ground insulating layer 2 is alleviated, so that the electric field distribution of the entire insulating coil is made more uniform and local electric field concentration is eliminated. Therefore, the insulation performance can be further improved.
[0030]
【The invention's effect】
According to this invention, by the prepreg tape formed by applying a semi-cured thermosetting resin to a nonporous insulating film substrate on the strand coil side of the ground insulating layer formed on the outer periphery of the strand coil Since the high electric field insulating layer is formed, the electric field performance of the ground insulating layer can be improved and the dielectric breakdown voltage characteristics can be improved. Therefore, it is possible to reduce the thickness of the ground insulating layer and to achieve the same insulation performance as before, so that the size of the insulating coil can be reduced and the effect of contributing to the downsizing of the rotating electrical machine can be achieved. Is obtained.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of an insulating coil showing a first embodiment of the present invention.
FIG. 2A is a partial cross-sectional view of an insulating coil showing a second embodiment of the present invention, and FIG. 2B is an enlarged cross-sectional view showing a B portion thereof.
FIG. 3A is a partial cross-sectional view of an insulating coil showing a third embodiment of the present invention, and FIG. 3B is an enlarged cross-sectional view of a B portion thereof.
FIG. 4 is a partial cross-sectional view of an insulating coil showing a fourth embodiment of the present invention.
FIG. 5 is a partial cross-sectional view of an insulating coil showing a conventional example.
[Explanation of symbols]
1 Wire coil
11 Conductor
12 Wire insulation
13 Head stuffing
2 Ground insulation layer
20 Second insulation layer
21. High electric field insulating layer (first insulating layer)
22 Impregnated insulating resin
3 Internal electric field relaxation layer
31 Conductive tape
32, 33 Prepreg insulation tape
34 Prepreg conductive tape

Claims (6)

A semi-cured thermoset on a laminated mica tape based on a non-porous film-like insulating material with high electric field strength around the outer periphery of a wire coil formed by winding an insulated wire on a conductor A first insulating layer formed by winding a prepreg laminated mica tape containing a resin, heating and pressing , and curing the semi-cured thermosetting resin, and an outer periphery of the first insulating layer after winding a porous tape-shaped insulating material, for rotary electric machine characterized by comprising forming a ground insulating layer of a thermosetting resin impregnated, and a second insulating layer formed by curing insulated coil.   The insulating coil for a rotating electrical machine according to claim 1, wherein an internal electric field relaxation layer is provided inside the first insulating layer.   3. The rotating electrical machine insulation coil according to claim 2, wherein the internal electric field relaxation layer is formed by sandwiching a conductive tape with a prepreg tape obtained by applying a semi-cured thermosetting resin to an insulating tape. An insulating coil for a rotating electrical machine, characterized by being a prepreg tape.   The insulating coil for a rotating electrical machine according to any one of claims 1 to 3, wherein an electric field concentration relaxation process is performed with a corner portion of the ground insulating layer formed in an arc shape. Semi-cured thermosetting resin on laminated mica tape based on non-porous film-like insulating material with high electric field strength around the periphery of the wire coil formed by winding the insulated wire on the conductor A step of winding a prepreg laminated mica tape containing, heating and pressure forming , curing the semi-cured thermosetting resin to form a first insulating layer, and an outer periphery of the first insulating layer A method of manufacturing an insulating coil for a rotating electrical machine, comprising: winding a porous tape-shaped insulating material on the substrate and impregnating and curing a thermosetting resin to form a second insulating layer. Conductive prepreg tape is wound around the outer periphery of a wire coil constructed by winding an insulated wire on a conductor, and a non-porous film-like insulating material with high electric field strength is formed on the base A prepreg assembled mica tape made of mica tape containing a semi-cured thermosetting resin is wound, heated and pressure-molded, and the semi-cured thermosetting resin is cured to form a first insulating layer. And a step of winding a porous tape-shaped insulating material around the outer periphery of the first insulating layer, impregnating and curing the thermosetting resin, and forming a second insulating layer. A method of manufacturing an insulating coil for a rotating electrical machine.

Images