JP2000023404A - Insulation structure of series-connection part of stator winding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate manufacturing and improve insulation. SOLUTION: The ends of half coils 1A and 1B are electrically connected to each other with a connection conductor 5 and a spacer 6. A bag-type soft insulating cap 17 is applied over the end and circumference of a series- connection part 2 in which the half coils are connected each other as mentioned above. A molded hard insulating pipe 18 is put on the circumferential surface of the insulating cap 17. After that, the series-connection part 2 is impregnated with resin and then the resin is thermally cured. The insulating cap 17 and the insulating pipe 18 can be attached easily and taping is not necessary, so that the manufacturing process can be simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulation structure for a series connection of stator windings, and more particularly to an insulation structure for a series connection of stator windings used in a large rotating electric machine manufactured by a total impregnation method. It is effective.

[0002]

2. Description of the Related Art In recent years, stator windings manufactured by a total impregnation method have tended to be large-sized in order to improve quality and reduce costs. Such large stator windings are being manufactured using half coils instead of full coils.

That is, as shown in FIG. 9, a large stator winding 1 has a half coil 1A and a half coil 1B,
The ends of the two half coils 1A and 1B are electrically connected at a series connection portion 2. And this series connection part 2
Is insulated.

Here, the electrical connection structure of the series connection portion 2 and the conventional insulation structure are shown in FIG. 10 which is a perspective view, FIG. 11 which is a cross-sectional view, and FIG.
This will be described with reference to FIG.

[0005] As shown in FIGS. 10 to 12, each of the half coils 1 A and 1 B is formed by winding a coil insulation 4 around a plurality of rectangular copper wires 3. Both half coils 1
The ends of A and 1B are connected with the connection conductor 5 and the spacer (conductor).
6 are electrically connected in series by brazing.

Since the half coils 1A and 1B are large, the series connection part 2 is also large and it is difficult to insulate the series connection part 2. Therefore, the following insulation structure is conventionally employed.

That is, around the ends of the half coils 1A and 1B and around the connection conductor 5, the cut insulating sheet 7 is bent and applied to the coil ends to form a bag-shaped insulating cap. . Further, taping insulation (glass fiber tape or tetron glass fiber tape) is placed on a bag-like insulation cap (a stack of a large number of insulation sheets 7).
(Taping) and fixed. In this way, by taping, the large-sized bag-shaped insulating cap is fixed and insulated while being tightened.

[0008] As described above, the stator winding 1 electrically connected and insulated is fitted and connected to the stator core, and the resin is integrally vacuum impregnated with the stator core. By this resin vacuum impregnation, the insulating structure of the series connection part 2 is also impregnated with the resin, and is heat-treated after the resin impregnation, whereby the impregnated resin is cured.

[0009]

However, the above-mentioned prior art has the following problems in the step of taping a bag-like insulating cap (a large number of insulating sheets 7) with a glass fiber tape or the like.

Since the series connection portion 2 is large in size, taping work is difficult. Because the space distance between adjacent series connection parts 2 is narrow,
Taping work is difficult. In particular, the taping process of the terminal unit requires skill, and if the taping is performed poorly, inconvenience such as slipping later occurs. In addition, since the end portion cannot be sufficiently tightened for taping, the size is large and the appearance is poor. Due to the above, a long working time is required. Further, the finished state is not constant and the appearance is poor. That is, the insulation structure of the series connection part 2 becomes irregular,
The appearance was getting worse.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and has as its object to provide an insulating structure for a series connection of stator windings which is easy to work and has good appearance.

[0012]

In order to solve the above-mentioned problems, according to the present invention, an insulating member is provided around a series connection portion formed by electrically connecting the ends of a half coil, and impregnated with a resin. In the insulating structure of the series connection portion of the stator winding obtained by thermally curing the impregnated resin, the insulating member covers a soft and bag-shaped insulating cap from an end of the series connection portion to a peripheral surface. In addition, a shaped hard insulating pipe is mounted on the peripheral surface of the insulating cap.

[0013] In the configuration of the present invention, the insulating cap is formed by laminating an insulating sheet on a wooden mold having a shape and dimensions corresponding to the series connection portion, bonding the insulating sheet to each other, and fixing the tape with a tape.
It is characterized by being formed by pulling out from the wooden mold.

[0014] In the configuration of the present invention, the insulating pipe may be formed on a winding core having a shape and dimensions corresponding to the insulating cap.
It is characterized in that a semi-cured tape or a semi-cured sheet is wound and heated.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing an insulating structure of a series connection portion of a stator winding according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG. As shown in both figures, each of the half coils 1A and 1B is formed by winding a coil insulation 4 around a circumference in which two rectangular copper wires 3 of 5.5 mm × 2.0 mm are bound in 40 rows in two rows. Both half coils 1A, 1
The ends of B are electrically connected in series by brazing the connection conductor 5 and the spacer (conductor) 6.

The series connection portion 2 formed by electrically connecting the ends of the half coils 1A and 1B is insulated by an insulating member including an insulating cap 17 and an insulating pipe 18, which will be described in detail later. . The insulating cap 17 and the insulating pipe 18 are the key components of the present invention.

As described above, the stator winding 1 to which the electrical connection and the insulating members (17, 18) have been applied is fitted and connected to the stator core, and is integrally formed with the stator (resin). Epoxy resin or polyester resin) is vacuum impregnated. By the resin vacuum impregnation, the resin is also impregnated into the insulating member of the series connection portion 2, and is heated (150 ° C.) after the resin impregnation process, whereby each portion of the stator winding 1 and the insulating members (17, 18) The resin impregnated in) cures.

The insulating cap 17 has a bag-like shape, is soft before the thermosetting of the impregnated resin, and is covered from the end of the series connection portion 2 to the peripheral surface. Around the insulating cap 17, a shaped and hard (hardened before the thermal curing of the impregnated resin) insulating pipe 18 is mounted (circularly mounted).

As a manufacturing procedure, first, an insulator such as a glass laminate is filled in a gap between the series connection portions 2 to eliminate the gap, and a soft insulating cap 17 is put on the gap and mounted. Thereafter, a shaped rigid insulating pipe 18 is mounted around the insulating cap 17.

As described above, since the insulating cap 17 is put on the series connection portion 2 and mounted thereon, and the insulating pipe 18 is mounted on the serial connecting portion 2, the time required for the insulating work is greatly reduced, and at the same time the insulating work is performed in a narrow space. Eliminating the need for taping work.

Further, the finish is uniform, the appearance is improved, and the commercial value is improved. That is, as shown in FIG. 3 in which the series connection portion is viewed from the outer periphery of the stator, the insulating pipe 18 is shaped, so that the intervals Δ are exactly aligned and the lines L1 and L2 are exactly aligned. . In FIG. 3, reference numeral 50 denotes an outer periphery of the stator core, and reference numeral 51 denotes an iron core clamp.

Here, the manufacturing process of the insulating cap 17 is as follows.
This will be described with reference to FIG. First, as shown in FIG. 4A, a wooden mold 20 having a shape and dimensions corresponding to the serial connection unit 2 is prepared.

Then, as shown in FIG. 4B, an insulating material obtained by cutting the laminated mica glass sheet (five sheets) and the varnish glass sheet (five sheets) in accordance with the bottom of the wooden mold 20 is cut. 21 is pressed against the bottom of the wooden form 20 and bonded. Next, as shown in FIG. 4C, the mica glass laminated sheet (5 sheets) and the varnish glass sheet (5 sheets)
The insulating material 22 cut in such a manner as to match the peripheral surface of the wooden mold 20 is wound and bonded to the peripheral surface of the wooden mold 20 while being pressed against the peripheral surface of the wooden mold 20. Further, the bonding operation shown in FIGS. 4B and 4C is repeated several times.

After a plurality of layers of the insulating materials 21 and 22 have been bonded, the upper surface thereof is taped with a tape 23 to form a wooden mold 20.
Then, the insulating cap 17 is manufactured as shown in FIG. Since the insulating cap 17 is in the shape of a soft bag, when the insulating cap 17 is pulled out from the wooden mold 20, it slightly deforms.

Next, the manufacturing process of the insulating pipe 18 will be described with reference to FIG.
This will be described with reference to FIGS.

As shown in FIG. 6, semi-cured mica tape (thickness 0.17 mm, width 20 mm) is applied to a core 30 composed of a metal hollow hollow tapered member 30A, 30B shown in FIG.
Wrap 31 three times with half wrap. Instead of the semi-cured mica tape 31, a semi-cured mica sheet may be used.

The wound semi-cured mica tape 31 is
Heat molding together with the core 30 in a furnace at 150 ° C. and curing. Thereafter, when the tapered members 30A and 30B of the core 30 are slid in mutually opposite directions along the longitudinal direction, FIG.
The hardened pipe (the wound semi-cured mica tape is hardened) 18A comes off from the core 30 as shown in FIG. The insulating pipe 18 shown in FIG. 8 is manufactured by cutting this pipe 18A to a length of 100 mm.

In addition, semi-cured mica tape (thickness 0.17
In the first embodiment, a thermosetting insulating pipe 18 wound with semi-cured glass fiber tape (thickness 0.15 mm, width 20 mm) is used as the first embodiment. In the third embodiment, a semi-cured glass resin bind tape (thickness: 0.3 mm, width: 19 mm) is used, and a thermosetting insulating pipe 18 is used. Table 1 shows the dielectric breakdown voltage measurement results when a glass fiber tape (0.13 mm thick, 20 mm wide) was wound twice with half wrap and tightened from above as a comparative example.

[0030]

[Table 1]

As can be seen from Table 1, in the present embodiment, the dielectric breakdown strength is improved and the reliability is improved as compared with the prior art.

[0032]

As described in detail with the above embodiments, in the present invention, since the series connection portion is simply covered with an insulating cap and mounted thereon with an insulating pipe, the insulating connection is merely required. The working time is greatly reduced, and the taping work in a narrow place is not required, thereby facilitating the work.

Further, since the insulating pipe is mounted on the insulating cap, the finish is uniform, the appearance is improved, and the commercial value is improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an insulating structure of a series connection portion of a stator winding according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a configuration diagram of an insulating structure of a series connection portion of a stator winding according to the embodiment as viewed from a stator outer peripheral side;

FIG. 4 is an explanatory view showing a manufacturing process of the insulating cap.

FIG. 5 is a perspective view showing a winding core.

FIG. 6 is a perspective view showing a manufacturing state of the insulating pipe.

FIG. 7 is a perspective view showing a state in which the insulating pipe is manufactured.

FIG. 8 is a perspective view showing an insulating pipe.

FIG. 9 is a configuration diagram showing a stator winding using a half coil.

FIG. 10 is a perspective view showing a conventional insulating structure of a series connection portion.

FIG. 11 is a cross-sectional view showing a conventional insulating structure of a series connection portion.

FIG. 12 is a sectional view showing a section taken along line XII-XII of FIG. 11;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stator winding 1A, 1B Half coil 2 Series connection part 3 Rectangular copper wire 4 Coil insulation 5 Connection conductor 6 Spacer 7 Insulation sheet (bag-shaped insulation cap) 8 Taping insulation 17 Insulation cap 18 Insulation pipe 20 Wood mold 21, Reference Signs List 22 insulating material 23 tape 30 core 31 semi-cured mica tape 50 stator core outer periphery 51 core clamp

Claims (3)

[Claims] 1. A stator winding formed by applying an insulating member around a series connection portion formed by electrically connecting the ends of a half coil, impregnating the resin, and thermosetting the impregnated resin. In the insulating structure of the series connection portion, the insulating member covers a soft, bag-shaped insulating cap from an end portion of the series connection portion to a peripheral surface, and forms a hard insulating material on the peripheral surface of the insulating cap. An insulation structure for a series connection of stator windings, wherein a pipe is mounted. 2. The insulating cap is formed by laminating an insulating sheet on a wooden mold having a shape and dimensions corresponding to the series connection portion, bonding the insulating sheet together with a tape, and then pulling out the wooden mold. The insulating structure of the series connection of the stator winding according to claim 1, wherein: 3. The stator winding according to claim 1, wherein the insulating pipe is formed by winding a semi-cured tape or a semi-cured sheet around a core having a shape and a size corresponding to the insulating cap and heating the core. Insulation structure of series connection part.