JPH04111257U - rotating electrical machine coil - Google Patents

Abstract

(57) [Summary] [Structure] In the present invention, a heat-shrinkable material is used as the base material of the mica tape, and the mica tape is wound around a coil to form a ground insulating layer. The wrinkles generated during mica taping are removed by shrinking the base material of the mica tape when the impregnated resin is heated and cured, thereby forming an insulated coil with void-free ground insulation by bringing the mica tapes into close contact. [Effect] According to the above means, when the ground insulating layer is formed by mica taping, even if curling wrinkles occur, since a heat-shrinkable material is used as the base material of the mica tape, the heating effect of the impregnated resin Before the impregnated resin hardens, the base material of the mica tape shrinks and wrinkles disappear. Furthermore, since it is not necessary to wind the mica tape with high tension, the tapes do not come into close contact with each other during resin impregnation, and a resin impregnation path is ensured, allowing the resin to quickly impregnate the tape layer.

Description

[Detailed explanation of the idea]

[Purpose of invention]

0001

[Industrial application field]

This invention relates to the winding of high-voltage rotating electric machines, and in particular, void-free technology for the ground insulation layer. Regarding.

0002

[Conventional technology]

Vacuum pressure impregnation insulation is used as the insulation method for high-voltage rotating electric machines. this Wrap dry mica tape, which has little adhesive, around a wire ring, and put this wire inside the tank. After drying in a vacuum, a solvent-free resin such as epoxy resin is poured in and high pressure is applied. Completely impregnate the dry mica tape layer etc. with resin, then heat and harden the resin in a drying oven to form a bottle. This is to form an insulating layer without any id.

0003 Dry mica tape, which forms this ground insulation, is generally made of chrome, which has excellent impregnation properties. A glass cloth base material such as a glass cloth base mica tape is used. In addition, in recent years Mica is a film base material that has excellent thermal properties and electrical properties, and is also advantageous in terms of economy and workability. Tape is also used.

0004 By the way, the impregnability of the vacuum pressure impregnated insulation method changes depending on the condition of the gaps between the mica tapes. Waru. This is because the resin impregnation is carried out through the gaps between the mica tapes, and the In order to make the insulation layer denser, it is necessary to wind the mica tape with high tension. Ru. However, when the mica tape is wound with high tension, there are fewer gaps between the mica tapes, so Resin impregnation speed becomes slow or impregnation is poor.

[0005] Therefore, there is a limit to winding with high tension, and currently when winding mica tape There are many wrinkles in the tape. Figure 3 is a cross-sectional view of a conventional winding wire. A state in which voids 7 are formed due to the winding wrinkles 5 that occur when the squid tape 5 is wound. This is what is shown. These curling wrinkles remain even after heat curing.

[0006] If the mica tape is wound many times, use a cloth base material with excellent impregnation properties, such as glass cloth. It is common to use a loss-based mica tape. However, the glass cloth base material Squid tape has the disadvantage that the taping process is poor because the tape does not stretch. Me is easy to occur. Furthermore, the cost also increases.

[0007] Film-based mica tape is advantageous in terms of economy and workability, but glass tape Unlike when using mica tape, a film base material does not require a cloth-like base material. There are no gaps in the material and the adhesion between the mica tapes is good. Therefore, the gap between the tapes is As the amount decreases further, impregnation of the resin becomes worse. Therefore, film-based mica tape has a low temperature. Mica tape must be wrapped with a glass cloth base. The mica tape will have more wrinkles than if it had been used.

[0008] Under such conditions, the ground insulation layer is impregnated using the vacuum pressure impregnation insulation method and heated. Even if you try to harden to form a void-free insulating layer, the wrinkles will still be visible during heating and hardening. The impregnated resin flows out and forms voids.

[0009]

[Problem that the idea aims to solve]

For this reason, the best way to eliminate voids in the creases is to eliminate the creases. Instead, a method is used to maintain good curling wrinkles and retain the impregnated resin in the curling wrinkles. was. Japanese Patent Publication No. 57-18419 is an example of this, in which mica tape is impregnated with resin. They added a catalyst that reacts with However, even with this method, there are many curly wrinkles. If the wrinkled area is large, it becomes difficult to retain the impregnated resin.

0010 In order to solve the above-mentioned drawbacks, the present invention has been developed to eliminate the curling wrinkles that occur during mica taping. A rotating electrical machine coil with void-free ground insulation, which is eliminated when the impregnated resin is heated and cured. The purpose is to provide [Structure of the idea]

[0011]

[Means to solve the problem]

In this invention, we use a heat-shrinkable material as the base material of the mica tape. is wound into a coil to form a ground insulating layer. Curling that occurred during mica taping Wrinkles are removed by shrinking the mica tape base material when the impregnated resin is heated and cured. , the mica tapes are closely bonded to form an insulated coil with void-free ground insulation. Ru.

0012

[Effect]

According to the above means, when forming the ground insulating layer by mica taping, Even if wrinkles occur, since the base material of the mica tape is a heat-shrinkable material, impregnation is not possible. When the resin is heated and cured, the base material of the mica tape shrinks before the impregnated resin hardens, resulting in curling. I will be gone. In addition, since there is no need to wrap the mica tape with high tension, the resin-containing During soaking, the tapes do not come into close contact and the resin impregnation path is secured, allowing the resin to quickly absorb into this tape layer. Impregnate.

[0013]

【Example】

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. Figure 1 shows the times This is a cross-sectional view of a heat-shrinkable mica tape 1 used in an electrical converter. A shrinkable film base material 3 is laminated together. The heat-shrinkable film base material 3 is , such as heat-shrinkable Lumirror (trade name manufactured by Toray Industries, Inc.) A and Hostaphan. There is RG type B (manufactured by Hoechst, West Germany), which has heat shrinkage characteristics as shown in Figure 2. have.

[0014] In the process of manufacturing mica tape, laminated mica paper 2 and heat-shrinkable film are The film base material 3 is pasted together by heating and drying using a small amount of adhesive. The heating temperature of It is laminated with grown mica paper 2. Use such heat-shrinkable mica tape 1 as a conductor. 4, for example, 3 times with 1/2 overlap, and after vacuum pressure impregnation, heat harden the impregnated resin. FIG. 4 shows a vertical cross section of the rotating electric machine coil in this state.

[0015] Immediately after winding the heat-shrinkable mica tape 1 around the coil conductor 4 in multiple layers, the Since squid tape is wound with low tension, winding wrinkles 6 occur. times in this state Figure 3 shows a longitudinal section of the converter coil.

[0016] However, after this coil is housed in the iron core and connected, and impregnated with vacuum pressure, the impregnated resin is In the process of heating and hardening the fat (generally at 130 to 150°C), the heat shrinkage shown in Figure 2 is performed. As can be seen from the heat shrinkage properties of the film base material 3, before the impregnated resin gels, The heat-shrinkable film base material 3 heat-shrinks, the heat-shrinkable mica tape 1 heat-shrinks, The winding wrinkles 6 are removed and the heat-shrinkable mica tapes 1 are brought into close contact. Then impregnated the tree Since the fat is thermoset, it is possible to form an insulating layer without voids. in this state FIG. 4 shows a longitudinal section of the rotating electrical machine coil.

[0017] In addition, even if heat-shrinkable mica tape 1 is rolled with a fairly low tension, it will eventually wind up. Since the wrinkles are removed, the impregnation path, which is the gap between the tapes in the mica tape insulation layer, is established. will be maintained. Therefore, resin impregnation is easily carried out along the layer direction of the mica tape. , it is possible to completely impregnate the resin, and in this respect, it is possible to form an insulating layer without voids. This makes it easier. (Other examples)

[0018] In the heat-shrinkable mica tape 1, a heat-shrinkable mica tape is used instead of the heat-shrinkable film base material 3. Even if a cloth made of shrinkable fibers is used as the base material for mica tape, the wrapping wrinkles will be similar. A rotating electrical machine coil that eliminates this can be obtained.

[0019] Figure 5 shows an example of the present invention applied to a 3kV class rotating electric machine coil, and the ta of the ground insulating layer This figure shows the results of determining nδ-voltage characteristics. Rotation of the conventional method shown in the same figure The characteristics of electric coils are such that there are voids due to winding wrinkles, and tan δ increases as the voltage increases. increases to On the other hand, the characteristics of the rotating electric machine coil of the present invention are Since there is no id, tanδ does not increase even when the voltage increases and becomes almost flat. . By configuring the rotating electric machine coil of the present invention in this way, the ground insulating layer is free from winding wrinkles. A highly reliable ground insulating layer can be formed.

[0020]

[Effect of the idea]

As described above, according to the present invention, the wrapping of the tape that occurs in the mica tape, which causes defects in the insulating layer. It is possible to remove wrinkles and make the insulation layer void-free. Therefore, a rotating electrical machine coil with excellent heat resistance and voltage resistance, and high quality and reliability can be obtained. effective.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a heat-shrinkable mica tape used in the present invention.

FIG. 2 is a diagram showing the heat shrinkage characteristics of the heat shrinkable film base material used in the present invention.

FIG. 3 is an enlarged cross-sectional view of a rotating electrical machine coil immediately after winding mica tape according to the present invention and a conventional method.

FIG. 4 is an enlarged cross-sectional view of the rotating electric machine coil after completion of heat curing in the present invention.

FIG. 5 is a comparison diagram of tan δ-voltage characteristics of the present invention and a conventional 3 kV class rotating electric machine coil.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1... Heat-shrinkable mica tape, 2... Laminated mica paper, 3... Heat-shrinkable film base material, 4... Conductor, 5
...Non-shrinkable mica tape, 6. Wrinkles, 7. Voids.

Claims (1)

[Scope of utility model registration request] [Claim 1] In a rotating electrical machine coil manufactured by winding mica tape around a conductor to form a ground insulating layer, impregnating it with a thermosetting resin and curing it by heating, the conductor is made into a heat-shrinkable film or cloth. A rotating electrical machine coil characterized by winding mica tape and using it as a mica tape base material.