JPS5824682Y2 - rotating electric machine - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotating electrical machine with reduced pressure inside the machine.

In recent years, there has been a rapid increase in the capacity of rotating electric machines, especially turbine generators.

This is due to advances in rotor shaft machines and improvements in cooling methods.

Stator cores and windings have already been water-cooled, and in recent years rotor windings have also been water-cooled.

As a result, fully water-cooled turbine generators have emerged that do not require hydrogen gas, which was conventionally used as a cooling gas.

In this case, the rotor operates in air, and the specific weight of air is 14 times that of hydrogen, increasing rotor loss due to frictional heat, which leads to an increase in rotor temperature and a decrease in generator efficiency. It will be disadvantageous.

As a countermeasure to the above, it is possible to depressurize the cabin,
Since there is nothing moving on the stator side, there is no need to consider friction loss, and since the stator coil has a high voltage, corona discharge and withstand voltage are issues (0.4kg/crrL2f is 0.1kg/crrL" (It has about three times the withstand voltage as compared to the 1000 kW), so it is advantageous not to reduce the pressure on the stator side of the machine.

Therefore, it is sufficient to provide a sealed insulating cylinder in the air gap between the stator and rotor to reduce the pressure inside the side cylinder.

However, since the insulating cylinder is located within the stator frame, there are problems such as difficulty in assembling the extraction pipe and oil being sucked into the insulating cylinder due to pressure reduction.

The present invention was devised in view of the above, and aims to provide a rotating electric machine equipped with an in-machine decompression device that is extremely simple and completely eliminates the fear of oil flowing into the rotor from the bearing section. .

An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a cross-sectional view of the end of a turbine generator.

1 is a rotor, 2 is a rotor coil, and 3 is an end ring that supports the rotor coil against centrifugal force.

The rotor coil 2 is water-cooled.

Cooling water enters the double pipe 4 from the center hole of the shaft and is supplied and discharged from the end of the shaft.

It rises from the double pipe 4 to the header 5 and is guided by a vibro.

Connecting pipe 7 and elevator from header 5 to each coil
Cooling water is supplied and discharged through the rotor 8, and all the heat generated in the rotor is carried away by the cooling water.

At this time, the friction loss due to rotation is 3600 R/
When rotating at M, it is 1200g x 900, which is about 150g.
It will be about KW.

This loss is 10 KWa degrees in hydrogen.

Therefore, the rotor 1 has an airtight structure with the insulating cylinder 9 and the bracket 10, and if the inside of the rotor 1 is reduced to a predetermined pressure, the friction loss will be reduced in proportion to the absolute pressure.

The problem here is the seal between the rotating part and the stationary part of the rotor 1 and the bracket 10.

There is an oil drain pipe 13 between the inner oil barrel 11 and the oil seal casing 12.

Drained oil from the bearing 14 is discharged from an oil drain pipe between the oil casing 12 and the outer oil cylinder 15 (bearing chamber).

Furthermore, bearing oil supply and oil supply into the casing 12 are performed separately.

Here, if the oil casing supply pressure is set to approximately 1-1 kg/crn''g, which is slightly higher than atmospheric pressure, the oil from the oil casing 12 will flow out into the bearing chamber and on both sides between the inner oil cylinder 11 and the casing 12.

Two rings, an inboard ring 16a and an outboard ring 16b, are built into the oil casing 12 as seal rings 16, and both rings 16a.

By adjusting the gap between the rotor 16b and the journal portion 1a of the rotor 1, it is possible to adjust the amount of oil inside and outside the machine.

Since the interior of the inside ring 16a is under reduced pressure, the gap is smaller than that of the outside ring 16b.

This seal oil allows the inside of the insulating cylinder 9 to be maintained in a reduced pressure state.

FIG. 2 is a system diagram of seal oil. Drainage oil from the bearing chamber is connected to an air extraction tank 20.

The oil drain pipe 13 between the inner oil barrel 11 and the casing 12 is connected to an expansion tank 21 which is a return tank, and the expansion tank 21 is reduced in pressure to a predetermined pressure by a vacuum pump 22.

Furthermore, if the slope of the oil drain pipe cannot be maintained in the oil system, the pressure in the main return oil tank 23 is reduced, so it is sufficient to adjust the tank pressure.

As mentioned above, according to the present invention, the pressure in the expansion tank, which is the return tank between the oil drain inside the machine and the seal casing, is depressurized, so the pressure is reduced between the inner oil cylinder and the cane puffer, which are connected to it, and a special exhaust gas is used. It is possible to provide a rotating electrical machine equipped with a vacuum sealing device that does not require oil pipes and does not require any oil to enter the machine.

[Brief explanation of drawings]

FIG. 1 is an end longitudinal sectional view of a fully water-cooled turbine generator showing an embodiment of the present invention, and FIG. 2 is a system diagram of its seal oil. DESCRIPTION OF SYMBOLS 1... Rotor, 11... Inner oil barrel, 12... Seal casing, 13... Oil drain pipe, 16a... Inner seal ring, 16b... Outer seal ring, 21...
... Expansion tank, 22... Vacuum pump.

Claims (1)

[Scope of utility model registration request] A rotating electric machine characterized in that the rotary electric machine is operated by reducing the pressure inside the machine, and the pressure is reduced in an expansion tank that is a return tank for waste oil between an inside oil cylinder and a seal casing by pressing a button on the rotating electric machine.