JPS62160056A - Cooler for rotary electric machine - Google Patents

Abstract

PURPOSE:To continuously cool a bearing oil until a rotary electric machine is stopped by providing a drain valve opened when a pump is defective at a position lower than a lower water tank in a cooling water return pipe of an oil cooling tube. CONSTITUTION:A drain groove 11 is formed at a position of approx. 10m under group. A cooling tower 5 and a lower water tank 6 are mounted on the ground. Accordingly, the head of a drain valve 7 from the tank 6 becomes approx. 10m. When a pump 11 is stopped for certain cause during the operation of a motor generator, the valve 7 is opened to feed cooling water in the tank 6 to an upper oil cooling tube 3 and a lower oil cooling tube 4 by utilizing the head of the cooling water in the tank 6. In this case, a check valve 8 is provided. Thus, the cooling water does not flow directly to the valve 7 through an air cooler 2 without intermediary of the upper and lower oil cooling tubes.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a cooling water system for a rotating electric machine.

[Conventional technology]

In recent years, chamber shaft type motor generators have been used as power sources for nuclear fusion experimental equipment. In other words, the moment of inertia of the rotor (
Hereinafter referred to as ``GD'') is increased, the rotation speed of the motor is increased to the top speed, the power of the motor is turned off, DC power is supplied to the rotor coil, and power is generated in pulses.Therefore, the motor.

It is equipped with an air cooler to cool the rotor coil and stator coil of the generator, and oil cooling pipes installed directly in the bearing oil tank to cool the upper and lower bearings. For this reason, a conventional cooling water system for a spindle type motor generator has a configuration as shown in FIG.

(1) is the water pump, (2) is the air cooler, (3) is the upper oil-cooled pipe, (4) is the lower oil-cooled pipe, (5) is the cooling tower, and (6) is the lower part of the cooling tower. It's a water tank. The cooling water in the lower water tank (6) is sent by the pump (1) to the air cooler (2), the upper oil cooling pipe (3), and the lower oil cooling pipe (4) for heat exchange, and then to the cooling tower (5). A circulation circuit is formed in which the water is cooled down and returned to the lower water tank (6). Note that (5a) is a cooling tower (5)
This is a filler that distributes water spray over a wide area to achieve evaporative cooling.

[Problem that the invention seeks to solve]

However, if the supply of cooling water stops due to pump (1) failure or loss of auxiliary power supply while the motor generator is operating, the motor generator wants to stop operation immediately, but in reality, the rotor Since the GD" of the motor is extremely large, it takes approximately one hour to stop the motor from its rated rotation.

In this case, the power to the electric motor, generator rotor, and stator coil is immediately turned off, so there is almost no loss in power generation, and there is no problem even if the water flow to the air cooler (2) is controlled at the top and bottom. Bearings generate heat while the motor generator is rotating.

When the water flow to the upper and lower oil cooling pipes (3) and (4) is stopped, the oil temperature rises, which has the disadvantage of causing a bearing burnout accident.

Further, even if the rotary electric machine is not an axle type, a rotating electric machine having a large GO'' has the same drawbacks as mentioned above.

The object of the present invention was made in view of the above-mentioned drawbacks, and it is possible to supply cooling water to the bearing oil cooling pipe until the rotating electric machine stops, without requiring another backup pump or an emergency power source for the pump in the event of a pump stop accident. The objective is to provide a cooling water device that can supply water.

[Means for solving problems]

In a cooling water system for a rotating electrical machine, the cooling water stored in the lower water tank of the cooling tower is circulated by a pump to the oil-cooled pipe installed for cooling the bearings of the rotating electrical machine, and then circulated back to the cooling tower. By installing a drain valve in the cooling water return piping at a position lower than the lower water tank, which is opened in the event of a pump stop accident, the cooling water is allowed to flow at the position water head until the rotating electric machine stops, and the l1i
This allows the lIl oil receiver to be cooled.

[For production]

With this structure, even if the pump stops due to an accident, the lower water tank is higher than the drain valve, so if the drain valve is opened, water can flow through the oil cooling pipe through the gap in the pump runner, and the rotation Bearing oil can continue to be cooled until the electric machine stops.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In Figure 1, the cooling water in the lower water tank (6) is pumped by the pump (1).
A circulation circuit in which water is sent to the air cooler (2), upper oil-cooled pipe (3), and lower oil-cooled pipe (4), where it exchanges heat, is cooled in the cooling tower (5), and is returned to the lower water tank (6). is formed. (7) is a water valve installed in the middle of the return pipe of the upper oil cooling pipe (3) and the lower oil cooling pipe (4), and is normally closed. (8) is a check valve, and when the drain valve (7) is opened to drain the cooling water to the drain groove (11), the air cooler (2
) to prevent cooling water from flowing into the drain valve (7) side. In addition, (12) in Figure 2 is the collector ring cover, (13) and (14) are the stator coil and rotor coil of the electric motor, (15) is the upper bearing, and (16) and (
17) is the stator coil and rotor coil of the rotating '77 machine, and (18) is the lower bearing.

Next, regarding the positional relationship between the lower water tank (6) and the drainage ditch (11), as shown in Figure 2, the total length of the spindle type motor generator is approximately 10 m.
Due to the above reasons, the entire installation and maintenance will be carried out in an underground pit.
, with only the collector ring cover (12) protruding from the floor. For this reason, the drainage ditch (11) is installed approximately 10 meters underground. On the other hand, cooling tower (5) and lower water tank (6)
is generally installed above the ground (ground level). Therefore, the head difference between the lower water tank (6) and the drain valve (7) is about 10 m.

Next, the operation of this embodiment will be explained.

In the cooling water system for a spindle type motor generator having the above configuration, if the pump (1) stops for some reason (failure, loss of power, etc.) while the motor generator is operating, the drain valve (
7) is opened to take advantage of the head difference in the cooling water in the lower water tank (6) and allow water to flow through the upper oil cooling pipe (3) and the lower oil cooling pipe (4). In this case, since there is a check valve (8), the cooling water passes through the air cooler (2) without going through the upper and lower oil cooling pipes and directly flows to the drain valve (
7) It does not flow into the side.

Next is the water volume in the lower water tank (6), which is approximately 250 MVA.
The amount of regular cooling water for a motor generator is approximately 5
deg, Air cooler approx. 3000 Q/mj, n Upper oil cooled pipe approx. 1000 Q/min Lower Ura cooled pipe approx. 100
0 Q/min total approximately 5000 Q/min
It will be about.

Generally, the lower water tank of a large cooling tower (5) has a total water volume of 5
It has a capacity of about 10 minutes. Therefore, if it is 5 minutes, 5000 n/min x 5m1n = 250
It becomes 00Q.

On the other hand, it takes about one hour for the generator to stop from its rated rotational state, and it is said that the amount of cooling water for the bearings until the generator stops is less than the rated value of 175 to sufficiently cool the bearings.

Therefore, the required amount of cooling water until it stops is 2000 Q/m
1nX 115X 60m1n = 24000Q
Therefore, the water stored in the lower water tank (6) can be sufficient. If the capacity of the lower water tank (6) is not sufficient, it is sufficient to plan for a larger capacity in advance. Also, if the overall pressure loss is 30 mAq in steady state, the water volume will be reduced to 175 in an emergency, so the pressure loss will be 30 mAq.
X (115)""1.2 mAq and head is 2
If it is at least m, water can flow through the upper and lower oil cooling pipes (3) and (4). Furthermore, even if a part of the piping is installed higher than the lower water tank (6), there is no problem because the cooling water will flow due to the siphon phenomenon.

[Other Examples]

In the present invention, the drain valve (7) has been described as a manual valve, but it is possible to install a sensor in the middle of the piping to detect a cooling water flow cutoff, and change the drain valve (7) to an automatic valve via a controller. It is also possible to drain the water.Furthermore, it is also possible to detect the rotational speed until the motor generator stops, and automatically control the amount of cooling water at that rotational speed using the drain valve (7) to reduce the amount of water drained. Also, if the rotation speed is high and the bearing loss is large, if the oil cooling pipe is attached directly to the bearing, the bearing itself will become very large, so it may be necessary to install a separate oil cooler.In this case. If you install an oil cooling pipe that has the cooling capacity necessary for an emergency stop and a regular oil cooler separately, and in an emergency, the necessary amount of cooling water flows only through the emergency oil cooling pipe, the bearing can be The same effects as the embodiment shown in FIG. 1 can be obtained without increasing the size.

Although the explanation has been given above regarding a spindle-type rotating electrical machine, it goes without saying that the same can be applied to a horizontal-shaft rotating electrical machine.

[Effects of the Invention] As described above, according to the present invention, when the cooling water circulation pump stops for some reason, the bearing oil pipe that is necessary for the bearing oil cooling pipe of the rotating electrical machine until the rotating generator stops. Cooling water can be supplied without the need for other backup pumps or backup power sources, making it possible to stop rotating electric machines in an emergency without burning out the bearings, creating a highly reliable cooling water system for rotating electric machines. can be provided.

[Brief explanation of drawings]

Fig. 1 is a system diagram showing the overall configuration of an embodiment of the cooling water system according to the present invention, Fig. 2 is a schematic diagram showing the positional relationship between the lower water tank, the drain valve, and the oil cooling pipe, and Fig. 3 is the conventional system. It is a system diagram showing the whole structure of a cooling water device. 1...Pump, 2...Air cooler, 3.
...Upper oil cooling pipe, 4...Lower oil cooling pipe, 5...Cooling tower, 6...Lower water tank, 7...Drain valve,
8...Check valve, 11...Drainage ditch,
15... Upper bearing, 18... Lower bearing. Agent Patent Attorney Inoue - Male Figure 1 Figure 2 Figure 8

Claims (2)

[Claims] (1) In a cooling water system for a rotating electrical machine in which the cooling water stored in the lower water tank of the cooling tower is circulated by a pump to an oil cooling pipe provided for cooling the bearings of the rotating electrical machine and then circulated back to the cooling tower,
A cooling water system for a rotating electrical machine, characterized in that a drain valve that opens in the event of a pump stop accident is provided in a cooling water return pipe of an oil cooling pipe at a position lower than the lower water tank. (2) Cooling water is supplied in parallel to the bearing oil cooling pipe and the air cooler of the rotating electric machine, and a check valve is installed in the cooling water return piping of the oil cooling pipe to prevent the air cooling water from communicating with the drain valve. A cooling water system for a rotating electric machine according to claim 1, characterized in that: