JPS6137857B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotating electrical machine equipped with a liquid-cooled stator and a rotor with claw-shaped magnetic poles.

Conventional generators driven by gas turbines have a maximum rotation speed of several tens of thousands of revolutions per minute. In such high-speed rotating electric machines, the stator side is generally liquid-cooled, but since the rotor side rotates at high speed, liquid cooling is difficult because the friction loss of the coolant in contact with the rotor is large. Furthermore, in synchronous machines, it was difficult to place the rotor's current collector in the coolant.

That is, the gap portion of the stator core facing the rotor is covered with a non-magnetic metal plate, the stator core around which the wire is wound is sealed, and cooling fluid is circulated within the stator core for cooling.

However, due to manufacturing technology, the non-magnetic metal plate had to be thick, resulting in large air gaps, and since it was made of metal, extremely large eddy currents were generated during high-speed rotation, resulting in high temperatures and inoperability.

Therefore, instead of the non-magnetic metal plate, a thin insulating layer is formed by applying epoxy resin or the like to a cloth-like insulating member such as glass cloth or a thin cylindrical insulating member, heat-curing it, and attaching it to the inner surface of the iron core. is being carried out.

However, since the rotor has claw-shaped magnetic poles, the magnetic velocity concentrates in the magnetic pole material portion facing the stator core, resulting in high temperatures during high loads. However, since the stator side that separates the air gap is an insulator, heat transfer in the circumferential direction is poor, and therefore heat dissipation from the rotor is poor, causing local thermal deformation of the rotor and causing vibration. There were drawbacks such as:

An object of the present invention is to provide a rotating electrical machine that can efficiently cool a rotor rotating at high speed.

EMBODIMENT OF THE INVENTION Below, one embodiment of the present invention shown in the drawings will be described. In FIG. 1, 1 is a stator frame, 2 is a laminated stator core, 3 is a holding plate that presses the end of the stator core, 4 is a seal ring welded to the holding plate 3,
5 is a stator winding, 6 is an end ring, 7 is an O ring interposed between the stator frame 1 and the end ring 6, 8 is a packing interposed between the seal ring 4 and the end ring 6,
Reference numeral 9 denotes an insulating layer made of an insulating material that extends from the stator core 2 to the seal ring 4 by coating a glass cloth with epoxy resin, heat-curing it, and pasting it. The stator side is cooled by flowing a cooling medium through holes 1a and discharging it to the outside through holes 1b. Reference numeral 10 denotes a rotor in which claw-shaped magnetic poles 11 made of magnetic material are integrated with a non-magnetic material 12 sandwiched therebetween. 13 is a bearing that supports the rotor 10, 14 is a bracket that supports the bearing, 14
a is a ventilation inlet, and 14b is a ventilation outlet. FIG. 2 shows a part of the cross section of the rotor 10, 15
is a part of a multi-start thread groove cut in the rotor surface in the same direction as the rotor's rotational direction.

Through rotation, the threaded grooves 15 cut on the surface of the rotor push out air in the gap between the rotor and the opposing stator core 2 toward the ventilation outlet 14b. Then, fresh air is sucked in from the ventilation inlet 14a side.
That is, the claw-shaped magnetic poles 11 of the rotor 10 generate heat, and the stator core 2 side is an insulating layer 9, so heat transfer is poor.The air in the gap is hot and light, so the rotor 10 rotates at high speed, it is discharged outside the machine by the pumping force of the multi-thread screw,
At the same time, cold (room temperature) air enters the cabin.

In addition, in general, the air gap magnetic flux changes greatly on the rotor surface and generates eddy currents, so the rotor surface is easily heated, but in this application, screw-shaped grooves are provided there, so eddy currents are reduced. The generation of heat itself is suppressed.

As described above, in the rotating electrical machine of the present invention, since the screw-shaped grooves are provided on the rotor surface, heat generation on the rotor surface is suppressed, wind flows well through the magnetic gap, and the inner peripheral surface of the stator It is possible to keep the temperature of the insulator that seals it low.

It goes without saying that the present invention can be implemented with various modifications without changing the gist thereof.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical sectional view showing one embodiment of the present invention, and FIG. 2 is a sectional view showing a part of the rotor surface. DESCRIPTION OF SYMBOLS 1... Stator frame, 2... Stator core, 9... Shiyahei layer, 10... Rotor, 11... Claw-shaped magnetic pole,
12...Nonmagnetic material, 15...Multi-thread thread groove.

Claims (1)

[Claims] 1. A rotor consisting of a rotor with claw-shaped magnetic poles and a stator whose surface facing the rotor is sealed with an insulating material and cooled with liquid, and characterized in that a screw-shaped groove is provided on the surface of the rotor. Electric machine.