JPS626854Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a cooling device for a rotating electric machine.

[Conventional technology]

Conventionally, in a cooling system that cools a rotating electric machine through a frame, an air cooling method is used in which a cooling fan is rotated by its own power or other power and cooling air is sent over the outer periphery of the frame that is closely fitted with the stator. Generally, water cooling methods are used, such as direct cooling with cooling water circulating through the frame, or cooling the internal air circulating inside the electrical equipment with cooling water. Another method has been proposed in which a heating element is cooled by utilizing the phase change of boiling and condensation of a condensable cooling medium (hereinafter referred to as a refrigerant).

In other words, a phase change occurs in which the refrigerant is boiled by the heat of the heating element in a closed chamber containing a heating element together with the refrigerant, becoming a gas (gas phase), and this gas is cooled and condensed in a condenser to return it to a liquid (liquid phase). is repeated, and during the cycle, when the liquid phase changes to the gas phase, the heat of the heating element is removed and cooled.

[Problems that this invention aims to solve]

However, in the case of a cooling device using the air cooling method,
Although the structure is very simple, the cooling capacity is small, and in the case of a cooling device that uses water cooling, the cooling capacity is large, but it requires a large amount of cooling water, so be careful not to cause rust or insulation deterioration. Boiling cooling has a large cooling effect, and when used to cool rotating electric machines, even if the load increases and the amount of heat generated increases, unlike water cooling, the circulating amount of cooling water cannot be controlled by other sources. There is no need to increase the cooling capacity by naturally accelerating the cycle of liquid phase → gas phase → liquid phase within the device, but since the heating element part is immersed in the refrigerant liquid, the rotating part Not only is sealing troublesome, but depending on the material, it may cause corrosion or generate non-condensable gas, which shortens the life of the rotating electrical machine, and also causes non-condensable gas to be discharged from the sealed refrigerant container. However, there were drawbacks such as a decrease in the cooling effect.

[Means for solving problems]

In consideration of these points, this proposal uses a double structure for the frame of the rotating electrical machine, fills the space between the inner frame and the outer frame with a refrigerant, and prevents components inside the rotating electrical machine, such as the iron core and coils, from coming into direct contact with the refrigerant. In addition, a gas vent port that can be opened and closed is provided at the top of the condenser provided on the frame, so that non-condensable gas can be discharged during maintenance work during use.

〔Example〕

The present invention will be explained below with reference to embodiments shown in the drawings.

In Figures 1 and 2, 1 is a double-structured frame (boiler) consisting of an inner frame 1a and an outer frame 1b, and a refrigerant 2 with a higher specific gravity than air (for example, Freon R113) is placed inside. . 3 is a stator that is fitted and fixed inside the inner frame 1a, 4 is a stator coil, 5 is a bracket that is fitted and fixed to both ends of the inner frame 1a, and 6 is rotatable to this bracket 5 via a bearing 7. a rotor 8 is fitted and fixed to the rotary shaft 6 so as to face the stator 3 with a radial gap therebetween; 9 is an airtight rotor supported on the upper part of the outer frame 1b; This condenser is made up of one or more cooling pipes 10 that communicate with the inside of the frame 1 and extend upward, and a cooling fan 11 that sends cooling air to the cooling pipes 10. 12 is a cooling fin provided on the outer periphery of the cooling pipe 10; 13 is a gas reservoir airtightly provided at the top of the condensing device 9, which communicates with all of the cooling pipes and has a gas vent 14 at the top. There is. The gas vent port 14 has an O ring 15 around it.
It is closed airtight by, for example, tightening and fixing the lid 16 with screws (not shown) or the like.

In such a configuration, when the rotating electrical machine starts operating and generates heat, the refrigerant 2 in the frame 1 takes heat from the stator 3 via the inner frame 1a, and the temperature rises and begins to boil, causing the vaporized refrigerant to boil. The steam rises into the cooling pipe 10 of the condenser 9.

In the condenser 9, a cooling fan 11 is driven while the rotating electric machine is operating, and when the cooling pipe 10 is filled with steam and receives ventilation from the cooling fan 11, the steam in the cooling pipe 10 loses heat. It is taken away, condensed, becomes liquid again, and falls into the frame 1 below. The refrigerant liquid that has returned to the frame 1 again absorbs heat from the rotating electrical machine and vaporizes, and is further condensed within the cooling pipe 10 and returns to liquid form. Repeat this cycle continuously.

By the way, in boiling cooling, it is necessary to vent gas in order to create a vacuum inside the device, but in the cooling device of the present invention, this is done as follows.

First, the first degassing is carried out by putting the refrigerant 2 in the atmosphere and injecting it into the frame 1 at least into the inner frame 1a.
After the screws (not shown) for tightening the lid 16 are not sufficiently tightened, the gas vent port 14 is left slightly open, and the stator coil 4 is energized to drain the refrigerant using the heat generated by the stator. Heat 2.

As the temperature of the refrigerant 2 rises, the refrigerant 2 begins to boil and vaporize, and the pressure inside the device rises above atmospheric pressure.Since the specific gravity of the refrigerant is heavier than air, the only gas that accumulates at the top is air, and this Air is exhausted from the gas vent 14. Good degassing can be achieved by repeating the above operation several times.

In addition, even if gas is vented once, after a long period of time, air will enter the device and the degree of vacuum inside the device will decrease, just like in a general boiling cooling device, but this cooling device does not work like a conventional boiling cooling device. Since the inside of the device is not sealed tightly and there is a gas vent at the top that can be opened and closed, even in such a case, maintenance work can be done to heat the stator coil 4 by energizing it and open the gas vent. By repeatedly opening and closing 14, the inside of the device is returned to a vacuum state, and a good cooling effect is maintained thereafter.

[Effects of this invention]

In this way, the present invention is a cooling device for a rotating electric machine, in which the stator has a frame with a double structure consisting of an inner frame that is fitted and fixed to the inner periphery and an outer frame that surrounds the inner frame. A condenser filled with a refrigerant having a specific gravity heavier than air to at least the height of the outer periphery of the inner frame, and comprising one or more cooling pipes and a cooling fan that sends cooling air to the cooling pipes at the top of the outer frame. The condenser is airtightly provided, and a gas vent that can be opened and closed and communicates with the cooling pipe is provided at the top of the condenser to remove the heat of vaporization required when the refrigerant in the frame changes from the liquid phase to the gas phase. Since the rotating electric machine is cooled by taking water from the rotating electric machine, it is possible to obtain a very high cooling effect. The rotating electric machine can be made compact, and since the refrigerant does not come into direct contact with the iron core, coils, insulators, etc. inside the rotating electric machine, there is no risk of rust, corrosion, or deterioration, and there is no risk of generating non-condensable gas. .

In addition, unlike conventional evaporative cooling devices, the cooling device of this invention does not seal the inside of the device, and has a gas vent at the top that can be opened and closed. Whenever it becomes necessary during the usage process, degassing can be easily performed as a maintenance work without providing a separate heat source, and the system can be used while maintaining the best cooling effect at all times.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the present invention, showing the upper half in cross section. FIG. 2 is a front view of FIG. 1, showing the left half in cross section. 1 is a frame, 1a is an inner frame, 1b is an outer frame, 2 is a refrigerant, 3 is a stator, 4 is a stator coil, 5 is a bracket, 6 is a rotating shaft, 7 is a bearing, 8 is a rotor, 9 is a condenser, 10 is a cooling pipe, 11 is a cooling fan, 12 is a cooling fin, 13
14 is a gas reservoir, 15 is an O-ring, and 16 is a lid.

Claims (1)

[Scope of utility model registration request] a stator that is fitted and fixed to the inner periphery of the frame;
A bracket attached to both ends of the frame, a rotating shaft rotatably supported by the bracket via a bearing, and a rotor fitted and fixed to the rotating shaft so as to face the stator with a gap in between. In a rotating electric machine having the above-mentioned frame, the frame has a double structure of an inner frame into which the stator is fitted and fixed, and an outer frame surrounding the inner frame, and the specific gravity between the inner frame and the outer frame is higher than that of air. one or more cooling pipes at the top of the outer frame;
A cooling device for a rotating electric machine, characterized in that a condenser comprising a cooling fan that sends cooling air to the cooling pipe is provided, and a gas vent that can be opened and closed and communicates with the cooling pipe is provided in the upper part of the condenser. .