JPH104647A - Supporting device for end part of rotor winding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a sufficient insulation performance also in relation to a centrifugal force acting on the end part of a winding of a rotor and, moreover, to make a supporting device suitable for assembling at site and have extremely high reliability. SOLUTION: This end part of a rotor winding has a structure, wherein support rings 6 fitted to the end part of a rotor core and fastening means for connecting a plurality of end parts of the rotor winding 2, projecting outward from the end part of the rotor core and the support rings 6 together, are provided and, wherein an outer insulation block 14 is disposed on the outside- diameter side of an electrical connection part 7, connecting an upper-side coil 2a and a lower-side coil 2b of the rotor winding 2 together, and further, the electrical connection part 7 including the outside insulation block 14 is covered with a single-opening insulation cap 11a. In this case, taper slides 13 are provided between the inside-diameter side of the electrical connection part 7 and the single-opening insulation cap 11a, so as to bring the single-opening insulation cap 11a, the outside insulation black 14 an the electrical connection part 7 into close contact with one another.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor winding end support device having an improved rotor winding end support structure for a large rotating electric machine such as a variable speed pumped generator.

[0002]

2. Description of the Related Art An AC variable speed pumping generator employs a system in which a three-phase distributed winding housed in a slot on the surface of a cylindrical rotor is AC-excited. Therefore, the end of the rotor winding had to be constrained by a method different from a normal turbine generator having a salient pole type rotor.

[0003] Generally, a rotor of a large variable speed pumping generator having a diameter exceeding 3 m is often assembled on site due to transportation restrictions. The portion accommodated in the rotor core is fixed by slot wedges, and the portion protruding outward from the end of the rotor core is fixed by a method as shown in FIGS. 5 and 6, for example.

That is, in FIGS. 5 and 6, a rotor winding 2 portion composed of an upper coil 2a and a lower coil 2b projecting outward from an end of a rotor core 1 has support blocks at several locations in the longitudinal direction. 3, a U-shaped fastening bolt (hereinafter referred to as a U-bolt) 4, which is a rotor winding fastening element, and is fixed by a nut 10 to a support ring 6 which is connected and fixed to an end of the rotor core 1 via a stay 5 via a stay 5. ing.

[0005] As an alternative to the U-bolt 4, a rotor winding fastening element may be fastened and fixed to the support ring 6 by a loop tie (not shown) made of glass fiber impregnated with a room temperature curable or heat curable resin.

In the method of supporting and fixing the rotor winding 2, the centrifugal force acting on the rotor winding during operation is transmitted to the support ring 6 via the U bolt 4. In this case, it is effective to position the U-bolt 4 at the outermost end (the upper end in FIG. 5) as close to the winding end as possible, whereby the winding end is bent and deformed in the radial direction. Can be extremely small.

However, in the rotor winding 2 as shown in FIG. 5, the upper coil 2a and the lower coil 2b are separately insulated as shown in the sectional view of FIG. After that, it is electrically connected to both ends.

Therefore, the insulation 8a of the electric connection portion 7 is to be implemented after the on-site assembly, and compared with the insulation 8b of the other portion where the thermosetting resin is vacuum impregnated at the factory in advance and sufficient hardening molding can be performed. Therefore, it cannot be denied that the mechanical strength is inferior.

On the other hand, if the position of the outermost U-bolt 4 is approached to the end of the winding end for the above-described reason, the U-bolt 4 is hooked on the insulation 8a of the electric connection portion 7. As described above, the insulation 8a of the electrical connection portion 7 is inferior in mechanical strength to the insulation 8b of the other parts, so that the rotor 8 has a large rotor diameter and a high peripheral speed. The insulation (8a) of the electrical connection portion 7 that contacts the inner diameter side of the outermost U bolt 4 due to the centrifugal force acting on the rotor winding 2 may be mechanically damaged, and the insulation performance may be reduced.

In order to solve this problem, for example, Japanese Patent Laid-Open No.
There is a structure as disclosed in Japanese Patent No. 03438. In this structure, as shown in FIG. 7, the outer insulating block 14a and the inner insulating block 14b are arranged by being brought into contact with the outer diameter side and the inner diameter side surface of the electric connection portion 7 of the upper coil 2a and the lower coil 2b, respectively. One-sided insulating cap 1 abutted on the outer diameter side surface of the outer insulating block 14a
1a, covering the electrical connection portion 7 with a one-sided insulating cap 11a.
The inside is filled with a room temperature-curable or heat-curable resin 12 and cured, and the U-bolt 4 is passed through the U-bolt 4 so as to enclose the one-sided insulating cap 11a at a position where the electrical connection portion 7 and the outer insulating block 14a overlap. It is fixed to the ring 6.

As a result, the centrifugal force acting on the end of the rotor winding 2 is changed by the electric connection 7 → the outer insulating block 14a →
Since the transmission is transmitted to the U-bolt 4 through the single-sided insulating cap 11a → the support block 3 and the solid member having the very small amount of compressive creep, the bending deformation of the end of the rotor winding 2 in the outer radial direction is minimized. Can be

At this time, it is important that the electrical connecting portion 7, the outer insulating block 14a, and the one-sided insulating cap 11a directly transmit centrifugal force without interposing a soft member having a large amount of compressive creep therebetween. If there is a gap between any one of the electric connection part 7, the outer insulating block 14a, and the one-sided insulating cap 11a during the assembling of the electric connection part 7, even if the filling resin 12 is hardened even if the filling resin 12 is filled and hardened. Under the surface pressure, the amount of compression creep of the filling resin 12 is large, so that the initial function cannot be exhibited.

Therefore, it is best that the electrical connection portion 7, the outer insulating block 14a, and the single-sided insulating cap 11a are brought into contact with no gap therebetween. However, JP-A-5-1034
No. 38 does not mention the specific method.

[0014]

As described above, in the conventional end structure of the rotor winding of the large rotating electric machine, the insulation of the winding due to mechanical damage depends on the appropriateness of the method of assembling the insulation of the electrical connection. There is a problem that the performance is significantly reduced.

An object of the present invention is to ensure sufficient insulation performance against a centrifugal force acting on a winding end of a rotor of a large-sized rotary electric machine such as a variable speed pumped generator. An object of the present invention is to provide an extremely reliable rotor winding end supporting device suitable for on-site assembly.

[0016]

In order to achieve the above object, the present invention provides a device for supporting a rotor winding end by the following means. The invention corresponding to claim 1 has a support ring attached to a rotor core end, an upper coil and a lower coil protruding outward from the rotor core end, and a gap between these two coils is provided. In a rotor winding end support device, comprising: a plurality of rotor winding ends connected by an electrical connection portion; and a fastening means for connecting each of the rotor winding ends to the support ring. An outer insulating block is arranged on the outer diameter side of the electrical connection between the upper coil and the lower coil, and the electrical connection including the outer insulating block is covered with a one-sided insulating cap, and the outer insulating block and A taper slide mechanism is provided between the inner diameter side of the electric connection portion and the one-sided insulating cap in order to bring the electric connection portion into close contact with each other.

Accordingly, in the rotor winding end supporting device according to the first aspect of the present invention, when the electric connection portion is covered with the insulating cap including the outer insulating block, the centrifugal force reaching the fastening means is reduced. Any gaps in the transmission path, as well as the room temperature curability with a large amount of compressive creep to fill this gap, no connection or thermosetting resin exist, and the centrifugal force acting on the ends of the rotor windings is all Since it is transmitted to the tightening means through a very small solid member, bending deformation of the rotor winding end in the outer diameter direction is minimized,
Sufficient reliability can be ensured even for the rotor winding of the high-frequency variable speed pumped generator.

According to a second aspect of the present invention, there is provided a support ring attached to an end of a rotor core, an upper coil and a lower coil projecting outward from the end of the rotor core. A plurality of rotor winding ends connected between the coils by an electrical connection portion, and a rotor winding end provided with fastening means for connecting each of the rotor winding ends and the support ring. In the supporting device, an outer insulating block is arranged on an outer diameter side of an electric connection portion between the upper coil and the lower coil, and a taper slide mechanism is provided on an inner diameter side of the electric connection portion, and the outer insulating block and the The electrical connection portion including the tapered slide mechanism is covered with a double-sided insulating cap, and an opening end of the double-sided insulating cap is closed with an insulating lid.

Therefore, in the rotor winding end supporting device according to the second aspect of the present invention, the tapered slide mechanism in the double-ended insulating cap can be assembled in the working posture from top to bottom, so that By fitting an insulating lid to the adhesive and adhering it, it is possible to improve the assembling workability at the winding end portion on the upper side of the rotating electric machine.

According to a third aspect of the present invention, there is provided a support ring attached to an end of a rotor core, an upper coil and a lower coil projecting outward from the end of the rotor core. A plurality of rotor winding ends connected between the coils by an electrical connection portion, and a rotor winding end provided with fastening means for connecting each of the rotor winding ends and the support ring. In the support device, the electrical connection between the upper coil and the lower coil is covered by an insulating sheet,
An outer insulating block is arranged on the outer diameter side of the electric connection portion, and a taper slide mechanism is provided on the inner diameter side, and the electric connection portion including the outer insulation block and the tapered slide mechanism is covered with a double-sided insulating cap. It was done.

Accordingly, in the rotor winding end supporting device according to the third aspect of the present invention, the electric connection portion is covered and covered with a very small insulating sheet having a compressive creep even under a high surface pressure. By doing so, the creepage distance can be reduced, and the axial length of the double-sided insulating cap can be shortened.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show the configuration of a first embodiment of a rotor winding end supporting device according to the present invention. FIG. 1 is a longitudinal sectional view, and FIG. 2 is an enlarged sectional view of a main part.

1 and 2, a rotor winding 2 composed of an upper coil 2a and a lower coil 2b is housed in a slot (not shown) provided in the rotor core 1, and is supported and fixed by a slot wedge. . Further, the distal ends of the upper coil 2a and the lower coil 2b protruding from the ends of the rotor core 1 are connected by an electric connection portion 7. A support ring 6 is attached to the end of the rotor core 1 via a stay 5 on the inner diameter side of the end of the rotor winding 2.

An outer insulating block 14 is disposed on the outer diameter side of the electrical connecting portion 7 between the upper coil 2a and the lower coil 2b, and the electrical connecting portion 7 including the outer insulating block 14 is further opened with a one-sided insulating cap 11a. cover. In this case, by attaching the outer insulating block 14 to the outer diameter side of the electrical connection portion 7 or the inner diameter side of the one-sided insulating cap 11a in advance, the workability during assembly can be improved.

Further, two tapered slides 13 each having a tapered portion are arranged on the inner diameter side of the electric connection portion 7, between the outer diameter side of the electric connection portion 7 and the outer insulating block 14, and between the outer insulating block 14. Outer diameter side and single opening insulating cap 11
a so that no gap is formed between them.

Thereafter, a thixotropic room-temperature-curable or heat-curable resin 12 is filled and hardened into the one-sided opening cap 11a. The support block 3 is arranged on the outer diameter side of the one-sided opening cap 11a, and the U-bolt 4 is held so that the one-sided insulation cap 11a is enclosed at a position where the electrical connection portion 7 overlaps the outer insulating block 14 and the support block 3. Then, the nut 10 is screwed and fixed to the support ring 6.

According to the first embodiment having such a configuration, the tapered slide 13 is arranged on the inner diameter side of the electric connection portion 7, and the tapered slide 13 is disposed between the outer diameter side of the electric connection portion 7 and the outer insulating block 14.
By tightly contacting between the outer diameter side of the outer insulating block 14 and the one-sided insulating cap 11a so as not to form a gap, the transmission path of the centrifugal force from the electrical connection portion 7 to the U-bolt 4 has a gap as well as a compression. Since there is no room-temperature-curable or heat-curable resin 12 having a large amount of creep, displacement of the electrical connection portion 7 in the outer diameter direction due to centrifugal force can be minimized.

FIG. 3 is a cross-sectional view of a main part of a second embodiment of a rotor winding end supporting device according to the present invention. The same parts as those in FIG. The description is omitted, and different portions will be described here.

In the second embodiment, as shown in FIG. 3, the electrical connecting portion 7 including the outer insulating block 14 is covered by a combination of a double-sided insulating cap 11b and an insulating lid 15.

In general, a large-sized pump generator has a vertical shaft structure. Therefore, in the case of the one-sided insulating cap 11a as in the first embodiment, the upper winding end of the generator has a bottom to top. It is necessary to assemble the tapered slide 13 in the one-sided insulating cap 11a in the working posture to move.

According to the above-described second embodiment, the tapered slide 13 in the double-ended insulating cap can be assembled in the working posture from top to bottom.
By fitting and bonding, it is possible to improve the workability at the time of assembly at the winding end on the upper side of the generator.

FIG. 4 is a cross-sectional view of a principal part showing the configuration of a third embodiment of a rotor winding end supporting device according to the present invention. The same parts as in FIG. The description is omitted, and different portions will be described here.

In the third embodiment, as shown in FIG. 4, the electric connecting portion 7 including the outer insulating block 14 is provided with a double-opening insulating cap 11b. In this case, the double-sided insulation gap 11b has an axial length that can secure a sufficient creepage distance according to the rated voltage of the rotor winding 2.

According to the third embodiment having such a configuration, the electrical connection portion 7 can be compressed even under a high surface pressure, and the axial length of the double-ended insulating cap 11b can be reduced. Further, as the insulating sheet 16, an aramid sheet having a minimal amount of compressive creep at an operating temperature even under a high surface pressure is suitable.

[0035]

As described above, according to the present invention, sufficient insulation performance is secured against centrifugal force acting on the winding end of the rotor of a large rotating electric machine such as a variable speed pumped generator. And a very reliable rotor winding end support device suitable for on-site assembly.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a main part of FIG. 1;

FIG. 3 is an enlarged sectional view of a main part, similar to FIG. 2, showing a second embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a main part, similar to FIG. 2, showing a third embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing a conventional rotor winding end support device.

FIG. 6 is a sectional view taken along the line AA of FIG. 5;

FIG. 7 is an essential part cross-sectional view showing another conventional end supporting device for a rotor winding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rotor iron core 2 ... Rotor winding 2a ... Upper coil 2b ... Lower coil 3 ... Support block 4 ... U bolt 5 ... Stay 6 ... Support ring 7 ... Electric connection part 8 ... winding insulation 8a ... connection part insulation 8b ... insulation other than connection parts 9 ... intermediate block 10 ... nut 11 ... insulation cap 11a ... one-sided insulation cap 11b ... double-sided insulation cap 12 ... filling Resin 13 Tapered slide 14 Insulating block 15 Insulating lid 16 Insulating sheet

Claims (3)

[Claims] 1. A support ring attached to an end of a rotor core, and an upper coil and a lower coil projecting outward from the end of the rotor core. A rotor winding end support device comprising: a plurality of connected rotor winding ends; and a fastening means for connecting each of the rotor winding ends to the support ring. An outer insulating block is disposed on the outer diameter side of the electrical connection between the coil and the lower coil, the electrical connection including the outer insulation block is covered with a one-sided insulating cap, and the outer insulation block and the electrical connection are provided. A taper slide mechanism is provided between the inner diameter side of the electrical connection portion and the one-sided insulating cap so as to make the two close contact with each other. 2. A support ring attached to an end of a rotor core, an upper coil and a lower coil projecting outward from the end of the rotor core, and an electrical connection is provided between the two coils. A rotor winding end support device comprising: a plurality of connected rotor winding ends; and a fastening means for connecting each of the rotor winding ends to the support ring. An outer insulating block is arranged on the outer diameter side of the electrical connection between the and the lower coil, a taper slide mechanism is provided on the inner diameter side of the electrical connection, and the outer insulating block and the taper slide mechanism are included. An electrical connection part is covered with a double-sided insulating cap, and an opening end of the double-sided insulating cap is closed with an insulating lid. 3. A support ring attached to an end of the rotor core, an upper coil and a lower coil projecting outward from the end of the rotor core, and an electrical connection is provided between the two coils. A rotor winding end support device comprising: a plurality of connected rotor winding ends; and a fastening means for connecting each of the rotor winding ends to the support ring. The electrical connection between the lower coil and the lower coil is covered by an insulating sheet, and an outer insulating block is disposed on the outer diameter side of the electrical connection, and a taper slide mechanism is provided on the inner diameter side. A supporting device for an end portion of a rotor winding, wherein the electrical connection portion including the block and the tapered slide mechanism is covered with a double-sided insulating cap.