JPS6362991B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotor cooling device for a rotating electrical machine such as a turbine generator, and more particularly to a rotor cooling device for a rotating electrical machine suitable for cooling rotor winding ends.

Generally, the end of the rotor winding in a turbine generator is cooled by introducing cooling air into the gap between the rotor spindle and the end of the rotor winding without using any special cooling method. is normal. A conventional example of a cylindrical rotor in which such cooling is performed is shown in FIGS. 1 and 2. 1st
In the figure, 1 is the rotor body, 3 is the end ring, 4 is the fan, 6 is the end of the rotor winding attached to the rotor body 1, and 2 is the space between the end ring 3 and the rotor body 1. A retaining ring is fixed across and holds the winding ends 6 against centrifugal forces through the shelving insulation 5, 7 is the rotor spindle, 8 is the gap between the ends of the rotor winding. FIG. 2 shows only one winding end of FIG. 1. In the figure, 9 is the top turn of the winding, 10, 11, and 12 are the second turns, respectively.
The third turn and bottom turns 13 and 14 are insulation between each turn (referred to as interstage insulation).

In a rotor with such a conventional structure, as shown by arrow 29 in FIG. It enters through the ventilation passage formed by the winding, and is introduced into the ventilation passage formed by the gap between the inner circumferential surface of the end 6 of the winding and the rotor spindle 7,
It then enters a slot provided in the rotor body. Here, the bottom turn at the end of the winding faces the flow of cooling air, so it is well cooled.
However, since the outer periphery of the winding ends (i.e., the top turn 9) is sealed with the body insulation 5, the gap 8 between the ends of the winding is closed to the inner periphery (i.e., the bottom turn 12).
Since only one side is open and the other side is closed, forming a blind alley, the cooling air introduced into this gap by centrifugal force has poor flow and is constantly stagnant, significantly reducing the cooling effect. There was a drawback. In other words, a sufficient cooling effect could not be obtained at the ends of the rotor windings.

Japanese Utility Model Application Publication No. 125514/1984 is an attempt to improve the cooling of the ends of the rotor windings. This is done by providing ventilation holes in the conductor in the radial direction at the ends of the rotor windings, and providing a large number of diagonal ventilation grooves on the inner surface of the trunk insulating plate that contacts the top of the winding ends. Irrespective of the relative positional deviation between the winding and the trunk, ventilation holes are formed from the windings to the inner grooves of the trunk, and the exhaust gas is discharged directly into the air gap through the numerous ventilation grooves provided at the end of the rotor core. This is what I tried to do.
However, in this case, the ventilation passage provided within the conductor at the end of the winding has a large ventilation resistance. Since cooling air is sent directly into the winding conductor, dust can easily enter. Processing time is required, such as drilling holes in the winding end conductor and creating grooves inside the body insulation. It is said that

The present invention has been made in view of the above points,
Therefore, it is an object of the present invention to provide a rotor cooling device for a rotating electrical machine that can improve the cooling of the ends of the rotor windings.

That is, the present invention provides a means for narrowing the ventilation gap at a position facing the bottom of the end conductor, and also provides means for narrowing the gap at a position facing the bottom of the end conductor, and also provides a means for narrowing the gap at a position facing the bottom of the end conductor, and also provides a means for narrowing the gap at a position facing the bottom of the end conductor, and also provides a means for narrowing the gap at a position facing the bottom of the end conductor. The above object is achieved by providing a cut groove that communicates with the gap between the wire ends.

The present invention will be explained below based on the illustrated embodiments. An embodiment of the present invention is shown in FIGS. 3 and 4. Note that parts that are the same as those in the conventional model are given the same reference numerals, and therefore their explanations will be omitted. In FIG. 3 one of the ends of the rotor winding is shown. As is clear from the figure, the cooling air that has entered the gap between the ends of the winding is transmitted to the gaps on both sides of the end (A and B in the figure).
part) from A to B as indicated by the arrow in the figure.
A cut groove 15 is provided in the top turn 9 at the end of the winding to allow ventilation. FIG. 4 shows the end of the rotor. As is clear from the figure, in the cooling air ventilation path formed by the gap between the rotor spindle 7 and the bottom turn of the winding end, the gap at the position facing the bottom of the end conductor becomes narrower. Yo,
A ventilation passage Batsuful 21 was attached to the bottom turn of the winding end. In addition, Batsuful 21 installed in this ventilation path.
are provided at the end of the winding on the end ring 3 side and at the bottom turn of every other winding end from the end of the winding, and the cut grooves 15 are provided at the end of the winding on the end ring 3 side They are provided at the top turn of every other winding end from that winding end. By providing such cut grooves and providing a buttful, the ventilation path between the end ring 3 and the rotor spindle is extended from the ventilation path between the rotor spindle and the inner circumferential surface of the end of the winding as shown by arrow 29 in the figure. Among the cooling air introduced into the ventilation passage and the gap between the ends of the winding as shown by the arrows in the figure, the cooling air introduced into the ventilation passage on the inner peripheral surface of the rotor spindle and the end of the winding. is between the winding ends 20 and 19,
The flow of cooling air becomes faster due to the narrowing of the ventilation path by the baffle 21. As a result, the pressure at the same portion decreases, and the cooling air in the gap 23 between the winding ends 20 and 19 is sucked toward the bottom turn side of the winding end as indicated by the arrow in the figure due to the siphon effect. Become so. Further, the cooling air that has entered the adjacent gap 22 is drawn into the gap 23 via a cut groove provided in the top turn of the winding end 20, as shown by the arrow. As this action is successively carried out on other winding ends, the flow of cooling air in the gap between the winding ends, which had been stagnant and had poor flow, is improved, and the winding ends are cooled. This allows for better cooling.

Another embodiment of the invention is shown in FIG. Not only one notch groove is provided in the top turn of the conductor at the end of the winding, but a plurality of small grooves are provided. In this way, the length of each groove becomes shorter than in the case of only one groove, and deflection of the cut groove of the top turn due to centrifugal force is prevented.

FIG. 6 shows yet another embodiment of the invention. As a means for narrowing the ventilation gap between the inner circumferential surface of the winding end and the rotor spindle and at a position facing the bottom of the end conductor, the winding end on the end ring side and its winding are Projections 42 are provided on the spindle surface facing the inner peripheral surface of every other winding end from the end. Even with this, the same effects as those described above can be achieved.

As described above, the present invention provides a means for narrowing the ventilation gap at a position opposite to the bottom of the end conductor, and continues in the circumferential direction to the conductor on the outer periphery of the winding end. In addition, since cut grooves are provided that communicate with the gaps between the ends of the windings, the cooling air introduced between the ends can be well circulated and exhausted, and the ends of the rotor windings can be cooled well. A rotor cooling device for a rotating electric machine can be obtained.

[Brief explanation of drawings]

Fig. 1 is a longitudinal side view showing the end of a conventional rotor;
FIG. 2 is a perspective view of the rotor winding end, FIG. 3 is a perspective view of the winding end showing an embodiment of the present invention, and FIG.
FIG. 5 is a perspective view of the winding end showing another embodiment of the present invention, and FIG. 6 is a rotor end showing still another embodiment. FIG. 1... Rotor body, 6... End of rotor winding,
7...Rotor spindle, 15...Notch groove, 1
9... End of rotor winding, 20... End of rotor winding, 21... Buzzful, 42... Protrusion.

Claims (1)

[Scope of Claims] 1. A rotor body, a rotor spindle, and a plurality of rotors that are attached to the rotor body and whose winding end conductors are wound with gaps in the axial direction. A rotor cooling device for a rotating electric machine, comprising windings and a retaining ring that covers the outer periphery of the end of these rotor windings, and a ventilation gap is formed between the rotor spindle and the inner peripheral surface of the end of the winding. In the apparatus, in the ventilation gap,
and a means for narrowing the gap at a position facing the bottom of the end conductor, and a means that is connected to the conductor on the outer periphery of the winding end in the circumferential direction and communicates with the gap between the winding ends. A rotor cooling device for a rotating electric machine, characterized in that it is provided with cut grooves that allow the cooling of a rotor. 2. In claim 1, the means for narrowing the ventilation gap at a position facing the bottom of the end conductor is formed by a ventilation passage provided on the inner circumferential surface of the winding end. A rotor cooling device for a rotating electric machine, which is characterized by: 3. In claim 1, the means for narrowing the gap at a position opposite to the bottom of the end conductor in the ventilation gap is provided at a position opposite to the inner circumferential surface of the winding end and on the spindle. A rotor cooling device for a rotating electrical machine, characterized in that it is formed by a protrusion provided on a surface.