JPH06292336A - Support of rotor winding end - Google Patents

Abstract

PURPOSE:To provide a rotor winding end support which provides the insulation strength required for an end part of a winding of a high-voltage rotor used in a large-sized variable speed generator without increasing the length of the rotor winding. CONSTITUTION:A support of a plurality of rotor winding ends 2c which are extended outward from the end of a rotor iron core has supporter rings 5 installed on the end of the rotor iron core l, U-shaped fastening bolts 3 which are fixed on the supporter rings 5 and allow the rotor winding ends 2c to pass through, and insulating blocks 3 which are placed between the U-shaped bolt 3 and the rotor winding end 2c, between the rotor winding ends 2c, and between the rotor winding end 2c and the supporter ring 5. An insulating layer 8 is formed on at least parts of the U-shaped bolts 3 which face a side face of the rotor windings.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary electric machine, and more particularly to a device for supporting a rotor winding end portion of a large rotary machine such as a variable speed pumped-storage power generator.

[0002]

2. Description of the Related Art Since a salient-pole type rotor is adopted in a normal hydraulic turbine generator, the rotor winding is wound around a salient-pole magnetic pole that also serves as a structure, and acts during operation. The rotor winding is restrained against the centrifugal force by a collar provided on the field pole.

On the other hand, the AC variable speed pumped-storage power generator employs a method of AC exciting the three-phase distributed windings provided in the cylindrical rotor, so that the centrifugal force acting during operation differs from the above. It is necessary to support and fix the rotor winding by a method. In the rotor winding of the conventional variable speed pumped storage generator, as shown in FIG.
And as shown in FIG. 6, the rotor winding (2) consisting of the upper winding (2a) and the lower winding (2b) is housed in the slot of the cylindrical rotor core (1), and a slot (not shown) is provided. The rotor winding end (2c) fixed by a wedge and protruding outward from the end of the rotor iron core (1) has the rotor winding end (2c) inserted at several points in the longitudinal direction. U-shaped bolts (3) for tightening are provided, and the ends of these U-shaped bolts (3) are attached to the end of the rotor core (1) via the stay (4) to the support ring (5). , And fixed by the nuts (6). In this case, between the U-shaped bolt (3) and the rotor winding end (2c), between the upper winding (2a) and the lower winding (2b), and between the rotor winding end (2c). ) And the support ring (5), an insulating block (7) is arranged for ensuring insulation strength according to the winding voltage so as to prevent discharge to a metal structure at ground potential. .

In the end supporting device of the rotor winding (2) having such a structure, the rotor winding end (2c) is in operation.
Since the centrifugal force acting on the support ring (5) is transmitted to the support ring (5) via the U-shaped bolt (3), the support ring (5) has a sufficiently large rigidity, and the support ring (5) moves toward the outer shape of the rotor winding end (2c). The deformation of can be suppressed to an extremely small value.

[0005]

Generally, the larger the size of the variable speed generator, the higher the excitation voltage of the rotor winding (2). At such a high voltage rotor winding end (2c), the potential difference with the U-shaped bolt (3) at the ground potential becomes large, so in order to increase the insulation strength, the rotor winding ends that are structurally adjacent to each other are increased. It is necessary to increase the distance between the parts (2c). However, in order to widen the space, the length of the rotor winding end portion (2c) must be inevitably lengthened, and the structure for supporting this must also be enlarged.

The present invention has been made in view of the above points, and it is an object of the present invention to provide the insulation strength necessary for the end portion of a high voltage rotor winding such as a large variable speed pumped-storage generator. It is an object of the present invention to provide a supporting device that can be secured without increasing the length of the rotor winding end portion.

[0007]

In order to achieve the above object, the present invention provides a rotor core end portion supporting device for a plurality of rotor winding end portions protruding outward from a cylindrical core end portion. A support ring attached to the support ring, a U-shaped bolt fixed to the support ring by sandwiching the rotor end, and between the U-shaped bolt and the rotor winding, the rotor winding end And an insulating block disposed between the rotor winding end and the support ring, and an insulating layer is provided on at least a portion of the U-shaped bolt facing the rotor winding side surface. It is what

[0008]

In the rotor winding support device having such a structure, the insulation strength required for the winding is improved by the insulating layer provided on the U-shaped bolt, so that the rotor of the high speed variable speed pumped-storage generator is improved. Even for the winding, sufficient reliability can be ensured without increasing the distance between the adjacent rotor winding end portions.

[0009]

(Embodiment 1) A first embodiment of the present invention will be described below with reference to the drawings. 1 to 3 show a configuration example of a support device for a rotor winding end portion according to the present invention. The upper winding (2a) and the lower winding (2b) of the rotor winding (2) are housed in slots (not shown) provided in the rotor core (1) and supported and fixed by slot wedges. A support ring (5) is attached to the end of the rotor core (1) via a stay (4) on the inner diameter side of the rotor winding end (2c). A U-shaped bolt (3) for tightening the rotor winding end portion (2c) is provided at a plurality of positions in the longitudinal direction of the rotor winding end portion (2c), and the end portion is provided with a nut (6). ) Are tightened and fixed to the support ring (5). In this case, between the U-shaped bolt (3) and the upper winding (2a), between the upper winding (2a) and the lower winding (2b),
An insulating block (7) is inserted between the lower winding (2b) and the support ring (5).

The upper winding (2) of the U-shaped bolt (3)
Epoxy glass prepreg tape is wound around a) and a portion facing the side surface of the lower winding (2b), and an insulating layer (8) formed by heat molding and curing is provided and then assembled. At this time, in order to increase the insulation strength, each insulation block (7) is provided with a groove (9), and the insulation block (7) is assembled and integrated with the insulation layer (8) of the U-shaped bolt (3).

According to this embodiment, the rotor winding end portion (2c)
The insulating strength between the U-shaped bolt (3) and the U-shaped bolt (3) is the effect of the insulating layer (8) provided on the U-shaped bolt (3), and the conventional U-shaped bolt (3) and the rotor without the insulating layer (8) Since it is higher than the insulation strength between the winding end (2c),
Even if the voltage of the rotor winding (2) is increased, it is not necessary to increase the distance between the adjacent rotor winding ends (2c) as in the conventional case. At this time, the thickness of the insulating layer (8) provided on the U-shaped bolt (3) is adjusted according to the voltage of the rotor winding (2). (Embodiment 2) In the second embodiment shown in FIG. 4, the insulation pipe (10) prepared in advance is inserted into the U-shaped bolt (3), and the first embodiment is used.
The same effect as that of the insulating layer (8) is obtained by arranging the insulating layer (8) at the same position, and the insulating layer (8) can be easily formed on the U-shaped bolt (3).

[0012]

As described above, according to the present invention, even in a high voltage rotor winding such as a large-sized variable speed pumped-storage power generator, the winding end length is minimized and sufficient insulation is achieved. It is possible to provide a support device for the rotor winding end portion that can secure strength.

[Brief description of drawings]

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

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along the line BB of FIG.

FIG. 4 is a longitudinal sectional view of a rotor end portion showing a second embodiment of the present invention.

FIG. 5 is a vertical sectional view showing a conventional example.

6 is a sectional view taken along the line CC of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rotor core 2 ... Rotor winding 2a ... Upper winding 2b ... Lower winding 2c ... Rotor winding end 3 ... U-shaped bolt 4 ... Stay 5 ... Support ring 6 ... Nut 7 ... Insulating block 8 Insulation layer 9 Groove 10 Insulation tube

Claims (1)

[Claims] 1. A support device for a rotor winding end protruding outward from a cylindrical core end, wherein a support ring attached to the rotor core end and the rotor end are sandwiched. U-shaped bolt fixed to the support ring, between the U-shaped bolt and the rotor winding, between the rotor winding ends, and between the rotor winding end and the support ring. And a U-shaped insulating block
An apparatus for supporting an end portion of a rotor winding, wherein an insulating layer is provided on at least a portion of the V-shaped bolt facing a side surface portion of the rotor winding.