JPS6210099B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotor for a rotating electrical machine, and more particularly to a rotor for a rotating electrical machine such as a turbine generator with improved insulation of rotor windings.

In general, the rotor of a rotating electric machine, particularly a turbine generator, has the following structure, as shown in FIG.
A slot 8 is provided near the surface of the rotor core 1 to pass through in the axial direction, and in the slot 8 there is a rotor winding 2 through which a current necessary to generate a magnetic field flows, and a slot between the rotor winding 2. An interlayer insulation 6 that electrically insulates each turn and a slot insulation 5 having a U-shaped cross section that insulates the ground of the rotor winding 2 are housed so as to cover the sides of an insulation block 3, which will be described later. ing. When the rotor rotates further, rotor winding 2
slot 8 so that it does not jump out of slot 8.
A dovetail-shaped groove is cut in and wedge 4 is provided.
An insulating block 3 is provided between the wedge 4 and the rotor winding 2 to electrically insulate the wedge 4 and the rotor winding 2.

With such a conventional rotor structure, when the voltage of the rotor winding 2 becomes high, dielectric strength becomes a problem.
In particular, the insulating block 3 between the rotor winding 2 and the wedge 4 has a creep distance of only a dimension (the length indicated by the bold line), and if a high voltage is generated, creepage failure will occur through the insulating block 3. In the case of the insulating block 3 to which a large voltage is applied, deterioration of the insulator will progress and the reliability of the generator etc. will be impaired. If the voltage increases, one solution would be to increase the thickness of the insulating block 3 to increase the creep distance a, but by increasing the thickness of the insulating block 3, the slot 8 can be installed in a limited space. Therefore, the insertion space for the rotor winding 2 is reduced. That is, the rotor winding conductor must be made thinner, and if this is done, the temperature of the rotor winding 2 will increase. In order to prevent the temperature from rising, it is necessary to sacrificing the mechanical strength of the iron core to make the slot 8 deeper or to make it longer in the axial direction, thereby solving the above-mentioned problems. It could not be said that it was a good countermeasure.

The present invention has been made in view of the above points, and its purpose is to increase the creep distance of the insulating block without sacrificing the mechanical strength of the iron core and without changing the slot space. We are able to provide rotors for rotating electric machines.

That is, the present invention provides a notch into which at least the opening tip of the slot insulation can be inserted, on the side surface of the winding of the wedge and facing the opening tip of the slot insulation. By fitting the tip of the opening. It was designed to achieve the intended purpose.

The present invention will be described in detail below based on embodiments shown in the drawings. Incidentally, the same reference numerals are used for the same parts as in the past.

FIG. 2 shows an embodiment of the present invention. Since its schematic configuration is almost the same as the conventional one, detailed explanation will be omitted here.

In the embodiment shown in the figure, a substantially semicircular wedge 4 is provided near the tip of a slot insulator 5 which is provided to insulate the rotor winding 2 to the ground and has a U-shaped cross section so as to cover the side surface of the insulating block 3. A notch 9 is provided, the tip of the slot insulator 5 protrudes from the notch 9, and a slot insulator cover 7 is provided in the notch 9 so as to cover the protruding portion of the slot insulator 5. The notch 9 is provided in the wedge 4 at the tip of the slot insulator 5, but since the maximum stress is usually applied to the dovetail-shaped wedge 4 at the part b, the notch 9 is provided at a location other than this part. ing.

By adopting this embodiment, the slot insulator can be constructed with almost the same size as the conventional one, without changing the space of the rotor winding 2, the insulating block 3, etc., by simply extending the tip of the slot insulator 5. The creep distance (indicated by c in Fig. 2) can be increased by the extension of 5, and even if the voltage increases, the insulation deterioration of the insulating block 3 will not progress much and the reliability of the generator etc. will be improved. This will improve the results.

FIG. 3 shows another embodiment of the invention. In the embodiment shown in the figure, a notch 9 is provided in the wedge 4 near the tip of the slot insulator 5, but in this embodiment, both ends of the wedge 4 facing the insulating block 3 side are cut off. A notch 9 is formed, and a slot insulation 5 is inserted into the notch 9 having such a shape.
The tip of the insulating block 3 is made to protrude, and a part of the insulating block 3 is inserted into the notch 9. This embodiment can also achieve the same effects as the embodiments described above.

According to the rotor of the rotating electrical machine of the present invention as described above, the portion of the winding side surface of the wedge that faces the opening tip of the slot insulation has a notch into which at least the opening tip of the slot insulation can be fitted. Since the opening tip of the slot insulation is inserted into the notch, there is no need to change the storage space for the rotor windings, insulation blocks, etc., and the structure is almost the same as the conventional one. Therefore, it is possible to obtain a rotor for a rotating electrical machine that can increase the creep distance of the insulating block without sacrificing the mechanical strength of the iron core or changing the slot space. can.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a rotor slot portion of a conventional rotating electric machine, FIG. 2 is a cross-sectional view of a rotor slot portion of a rotating electric machine according to an embodiment of the present invention, with a portion omitted, and FIG. FIG. 7 is a cross-sectional view showing a rotor slot portion of a rotating electrical machine according to another embodiment of the present invention, with a portion omitted. 1... Rotor core, 2... Rotor winding, 3...
Insulating block, 4... Wedge, 5... Slot insulation, 6... Interlayer insulation, 7... Slot insulation cover, 8... Slot, 9... Notch.

Claims (1)

[Scope of Claims] 1. A rotor core having a slot extending in the axial direction near the surface, a winding housed in the slot of the rotor core, and a winding disposed in the opening of the slot,
a wedge holding a winding; an insulating block interposed between the wedge and the winding; and a slot insulator interposed between the winding and the wall of the slot, the slot having a U-shaped cross section. In the rotor of a rotating electric machine, the winding side surface of the wedge includes:
A notch into which at least the opening tip of the slot insulation can be fitted is provided in a portion facing the opening tip of the slot insulation, and the opening tip of the slot insulation is fitted into the notch. The rotor of a rotating electric machine. 2. A protrusion extending in the axial direction is provided on a side surface of the wedge of the insulating block and in a portion facing the notch of the wedge, and the protrusion is fitted into the notch. A rotor for a rotating electric machine according to claim 1. 3. Claim 1 or 2, characterized in that the cutout has a substantially semicircular shape.
The rotor of the rotating electric machine described in Section 1.