Pump-free self-circulation evaporative cooling system for vertical hydro-generator rotor

Abstract

The invention discloses a pump-free self-circulation evaporative cooling system for a vertical hydro-generator rotor, and relates to the technical field of rotor cooling. In order to solve the problems that an existing stator bar adopts an evaporative cooling mode, a rotor also adopts an air cooling mode, for a hydraulic generator with higher power density, the air cooling mode of the rotor cannot meet the requirement, and the temperature is easy to exceed the standard during operation. The coil comprises a coil body, a cooling channel is arranged in the coil body and communicated with a cooling pipeline in which a cooling medium can flow, the cooling pipeline comprises a liquid supply pipe and an air outlet pipe, an outlet of the liquid supply pipe is communicated with an inlet of the cooling channel, and an inlet of the liquid supply pipe is communicated with condensing equipment. According to the invention, the water wheel generator rotor also uses the evaporative cooling technology, the evaporative cooling technology and the stator evaporative cooling technology form a matched combination, phase change heat absorption is utilized by evaporative cooling, so that the cooling effect is better, and the condition that the temperature exceeds the standard during operation of the high-power density water wheel generator can be avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of rotor cooling, and particularly to a pump - less self - circulating evaporation cooling system for the rotor of a vertical hydro - generator. Background Art

[0002] At present, there are three cooling methods for large hydro - generators with a capacity of over 600MW (referred to as giant units). One is the full - air cooling method; the second is the evaporation cooling method; and the third is the water - internal - cooling method. Among them, evaporation cooling, which is also a direct - cooling method, is more popular than the water - internal - cooling method due to its safety and reliability.

[0003] Currently, only the stator bars adopt the evaporation cooling method, while the rotor still adopts the air - cooling method. The air - cooling method belongs to the external - cooling method. For general generators with a relatively small capacity, it can meet the requirements. However, for hydro - generators with a higher power density, the full - air - cooling of the external - cooling technology cannot meet the requirements, resulting in the temperature of the high - power - density hydro - generator being prone to exceed the standard during operation, and the use effect is not good.

[0004] In summary, the existing stator bars adopt the evaporation cooling method, while the rotor still adopts the air - cooling method. For hydro - generators with a higher power density, the air - cooling method for the rotor cannot meet the requirements, and there is a problem that the temperature is prone to exceed the standard during operation. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem that in the existing situation where the stator bars adopt the evaporation cooling method while the rotor still adopts the air - cooling method, for hydro - generators with a higher power density, the air - cooling method for the rotor cannot meet the requirements and there is a problem that the temperature is prone to exceed the standard during operation. Furthermore, a pump - less self - circulating evaporation cooling system for the rotor of a vertical hydro - generator is provided.

[0006] The technical solution of the present invention is: a pump - less self - circulating evaporation cooling system for the rotor of a vertical hydro - generator, including: a coil body, which has a cooling channel inside, and the cooling channel is connected to a cooling pipeline through which a cooling medium can flow; The cooling pipeline includes a liquid supply pipe and an air outlet pipe. The outlet of the liquid supply pipe is connected to the inlet of the cooling channel, and the inlet of the liquid supply pipe is connected to a condensation device; The inlet of the air outlet pipe is connected to the outlet of the cooling channel, and the outlet of the air outlet pipe is connected to the condensation device; The inlets of the liquid supply pipe and the outlet of the air outlet pipe are both located at the center of the rotor, and their radial positions are different when the rotor rotates. The pressure difference between the liquid - supply - pipe side and the air - outlet - pipe side is used to drive the flow of the cooling medium.

[0007] Further, it is characterized in that the inlet of the cooling channel is communicated with the outlet of the insulating liquid infusion pipe through a liquid inlet joint, and the outlet of the liquid supply pipe is communicated with the inlet of the insulating liquid infusion pipe.

[0008] Further, the outlet of the cooling channel is communicated with the inlet of the insulating gas transmission pipe through a liquid outlet joint, and the inlet of the gas outlet pipe is communicated with the outlet of the insulating gas transmission pipe.

[0009] Further, a liquid-side electrical joint is connected to the liquid inlet joint, and a gas-side electrical joint is connected to the liquid outlet joint.

[0010] Further, the cooling pipeline further includes: a liquid distribution ring pipe and a gas distribution ring pipe arranged in parallel in the rotor, the outlet of the liquid supply pipe is communicated with the liquid distribution ring pipe, and the inlet of the insulating liquid infusion pipe is communicated with the liquid distribution ring pipe; The inlet of the gas outlet pipe is communicated with the gas distribution ring pipe, and the outlet of the insulating gas transmission pipe is communicated with the gas distribution ring pipe.

[0011] Further, the coil body has multiple groups arranged circumferentially, and the inlets of the insulating liquid infusion pipes of the multiple groups of coil bodies are simultaneously communicated with the liquid distribution ring pipe; The outlets of the insulating gas transmission pipes of the multiple groups of coil bodies are simultaneously communicated with the gas distribution ring pipe.

[0012] Further, an insulating layer is provided between adjacent coil bodies.

[0013] The present invention has the following effects compared with the prior art: The vertical hydro-generator rotor pump-free self-circulating evaporation cooling system provided by the present invention enables the hydro-generator rotor to also use the evaporation cooling technology, forming a supporting combination with the stator evaporation cooling technology. Evaporation cooling utilizes the heat absorption of phase change, which will make the cooling effect better and can avoid the situation of over-temperature during the operation of high-power density hydro-generators.

[0014] The vertical hydro-generator rotor pump-free self-circulating evaporation cooling system provided by the present invention uses the rotation of the rotor to provide power for the rotor cooling circuit, simplifies the cooling circuit, improves the reliability, reduces the pressure at the inlet and outlet of the cooling medium from the rotor, reduces the rotor temperature, keeps the temperature of the generator within the allowable range, and improves the safety and reliability of the generator at the same time. Description of the Drawings

[0015] Figure 1 is the overall structural schematic diagram of the present invention; Figure 2 is Figure 1 the rotating sectional view at A-A in Figure 3 is Figure 1Enlarged view of area B in the figure.

[0016] In the figure: 1. Coil body; 2. Liquid supply pipe; 3. Air outlet pipe; 4. Liquid inlet joint; 5. Insulated liquid infusion pipe; 6. Liquid outlet joint; 7. Insulated gas transmission pipe; 8. Liquid side electrical joint; 9. Gas side electrical joint; 10. Liquid distribution ring pipe; 11. Gas distribution ring pipe; 12. Insulation layer. Specific implementation mode

[0017] Specific implementation mode one: Combining Figure 1 、 Figure 2 This implementation mode is described. This implementation mode includes a coil body 1. The coil body 1 has a cooling channel inside. The cooling channel is connected to a cooling pipeline through which a cooling medium can flow. The cooling pipeline includes a liquid supply pipe 2 and an air outlet pipe 3. The outlet of the liquid supply pipe 2 is connected to the inlet of the cooling channel, the inlet of the liquid supply pipe 2 is connected to a condensation device (not shown in the figure), the inlet of the air outlet pipe 3 is connected to the outlet of the cooling channel, and the outlet of the air outlet pipe 3 is connected to the condensation device. The inlets of the liquid supply pipe 2 and the outlet of the air outlet pipe 3 are both located at the center of the rotor, and their radial positions are different when the rotor rotates. The pressure difference between the liquid supply pipe 2 side and the air outlet pipe 3 side is used to drive the flow of the cooling medium.

[0018] It should be noted that before the unit is started, the liquid supply pipe 2 side and the air outlet pipe 3 side of the rotor coil body 1 are filled with a liquid medium, and their liquid levels are also equal. Therefore, there is no pressure difference. When the rotor rotates, due to the different radial positions of the liquid supply pipe 2 and the air outlet pipe 3 entering and exiting the rotor from the center of the rotor, a small pressure difference where the liquid supply pipe 2 side is greater than the air outlet pipe 3 side will be generated.

[0019] The self-circulating evaporation cooling system without a pump for the rotor of the vertical hydro-generator in this implementation mode enables the rotor of the hydro-generator to also use the evaporation cooling technology, forming a supporting combination with the stator evaporation cooling technology. Evaporation cooling uses the heat absorption during phase change, which will make the cooling effect better and can avoid the situation of over-temperature during the operation of high-power density hydro-generators.

[0020] Specific implementation mode two: Combining Figure 1 、 Figure 2 This implementation mode is described. The difference between this implementation mode and the first specific implementation mode is that the inlet of the cooling channel is connected to the outlet of the insulated liquid infusion pipe 5 through the liquid inlet joint 4, and the outlet of the liquid supply pipe 2 is connected to the inlet of the insulated liquid infusion pipe 5. Whether it is an open coil or a closed coil, the liquid inlet joint 4 is always connected to the turn of the coil close to the pole shoe. The liquid inlet joint 4 plays an intermediate connection role to ensure the flow of the cooling medium between the cooling channel and the insulated liquid infusion pipe 5. Other components and connection relationships are the same as those in the first specific implementation mode.

[0021] Specific implementation mode three: Combining Figure 1 、 Figure 2To describe this embodiment, the difference between this embodiment and the second specific embodiment lies in that the outlet of the cooling channel is communicated with the inlet of the insulating gas transmission pipe 7 through the liquid outlet joint 6, and the inlet of the air outlet pipe 3 is communicated with the outlet of the insulating gas transmission pipe 7. The liquid outlet joint 6 plays an intermediate connection role to ensure that the cooling medium can flow between the cooling channel and the insulating gas transmission pipe 7. Other components and connection relationships are the same as those in the second specific embodiment.

[0022] Specific embodiment four: Combining Figure 1 、 Figure 2 To describe this embodiment, the difference between this embodiment and the third specific embodiment lies in that a liquid-side electrical joint 8 is connected to the liquid inlet joint 4, and a gas-side electrical joint 9 is connected to the liquid outlet joint 6. Connecting the liquid-side electrical joint 8 and the gas-side electrical joint 9 to a power source can energize the coil body 1. Other components and connection relationships are the same as those in the third specific embodiment.

[0023] Specific embodiment five: Combining Figure 1 、 Figure 2 To describe this embodiment, the difference between this embodiment and the third specific embodiment lies in that the cooling pipeline further includes a liquid distribution ring pipe 10 and a gas distribution ring pipe 11 arranged in parallel in the rotor. The outlet of the liquid supply pipe 2 is communicated with the liquid distribution ring pipe 10, the inlet of the insulating liquid transmission pipe 5 is communicated with the liquid distribution ring pipe 10, the inlet of the air outlet pipe 3 is communicated with the gas distribution ring pipe 11, and the outlet of the insulating gas transmission pipe 7 is communicated with the gas distribution ring pipe 11. The liquid distribution ring pipe 10 and the gas distribution ring pipe 11 play an intermediate transmission role, and because they are in an overall ring shape, they are convenient to connect and more convenient to use. Other components and connection relationships are the same as those in the third specific embodiment.

[0024] Specific embodiment six: Combining Figure 1 、 Figure 2 To describe this embodiment, the difference between this embodiment and the fifth specific embodiment lies in that the coil body 1 has multiple groups arranged circumferentially. The inlets of the insulating liquid transmission pipes 5 of the multiple groups of coil bodies 1 are simultaneously communicated with the liquid distribution ring pipe 10, and the outlets of the insulating gas transmission pipes 7 of the multiple groups of coil bodies 1 are simultaneously communicated with the gas distribution ring pipe 11. Each group of coil bodies 1 is cooled separately, and the cooling medium is evenly distributed, resulting in a better cooling effect. Other components and connection relationships are the same as those in the fifth specific embodiment.

[0025] Specific embodiment seven: Combining Figure 1 、 Figure 3 To describe this embodiment, the difference between this embodiment and the sixth specific embodiment lies in that an insulating layer 12 is provided between adjacent coil bodies 1. The insulating layer 12 insulates the coil bodies 1 to ensure the safe operation of the rotor. Other components and connection relationships are the same as those in the sixth specific embodiment.

[0026] The working principle of this embodiment: The cooling medium enters the liquid supply pipe 2 from the center of the rotor, then enters the liquid distribution ring pipe 10, and respectively enters the electrically insulated insulating liquid infusion pipes 5 of each coil body 1 through the liquid distribution ring pipe 10, and then enters the internal channel of the coil body 1 composed of two or multiple parallel hollow copper wires through the liquid inlet joint 4 on the coil body 1, and flows out from the liquid outlet joint 6 under pressure.

[0027] Initially, due to the different radial positions of the liquid supply pipe 2 and the gas outlet pipe 3 entering and exiting the rotor from the center of the rotor, a small pressure difference greater on the side of the liquid supply pipe 2 than on the side of the gas outlet pipe 3 will be generated. When the rotor coil body 1 is energized, the rotor coil body 1 will heat up, heating the cooling medium. When the evaporation temperature of the medium is reached, the cooling medium absorbs the heat of the rotor coil body 1, and part of it is converted from liquid to gas, forming a two-phase flow flowing in the coil.

[0028] This two-phase flow enters the electrically insulated insulating gas transmission (gas-liquid two-phase flow) pipe through the liquid outlet joint 6, then enters the gas distribution (gas-liquid two-phase flow) ring pipe, and finally returns to the center of the rotor through the gas transmission pipe exiting the rotor.

[0029] Before the unit is started, the liquid supply pipe 2 side and the gas outlet pipe 3 side inside the rotor coil body 1 are filled with liquid medium, and at the same time their liquid levels are equal, so there is no pressure difference. When the rotor rotates, due to the different radial positions of the liquid supply pipe 2 and the gas outlet pipe 3 entering and exiting the rotor from the center of the rotor, a small pressure difference greater on the side of the liquid supply pipe 2 than on the side of the gas outlet pipe 3 will be generated.

[0030] When the coil body 1 is energized, heat starts to be generated inside the coil body 1, heating the cooling medium inside. When the evaporation temperature is reached, part of the liquid will be converted into gas, resulting in the density of the medium on the liquid supply pipe 2 side being greater than the density of the medium on the gas outlet pipe 3 side. Therefore, the centrifugal pressure on the liquid supply pipe 2 side is greater than the centrifugal pressure on the gas outlet pipe 3 side. At this time, a pressure difference greater on the liquid supply pipe 2 side than on the gas outlet pipe 3 side will also be generated in the coil body 1. Under the action of these two pressure differences, the cooling medium is pushed to move, realizing pump-free self-circulation.

[0031] As it flows forward, the dryness of the two-phase flow in the coil body 1 gradually decreases, reaching the minimum at the outlet of the rotor coil body 1, that is, at the liquid outlet joint 6, and then remains unchanged to reach a steady two-phase flow. The greater the current, the more cooling medium evaporates, the greater the pressure difference between the two sides, the greater the circulating flow rate flowing in the coil, and the stronger the cooling capacity.

[0032] The content of the present invention is not limited to the content of the above embodiments. The combination of one or several specific embodiments can also achieve the purpose of the invention.

Claims

1. A rotor pump-free self-circulating evaporation cooling system for a vertical hydro-generator, comprising: Coil body (1), a cooling channel is provided inside the coil body (1), and the cooling channel is communicated with a cooling pipeline for a flowable cooling medium; It is characterized in that the cooling pipeline includes a liquid supply pipe (2) and an air outlet pipe (3), the outlet of the liquid supply pipe (2) is communicated with the inlet of the cooling channel, and the inlet of the liquid supply pipe (2) is communicated with a condensing device; The inlet of the air outlet pipe (3) is communicated with the outlet of the cooling channel, and the outlet of the air outlet pipe (3) is communicated with the condensing device; The inlets of the liquid supply pipe (2) and the outlet of the air outlet pipe (3) are both located at the center of the rotor, and their radial positions are different when the rotor rotates, and the pressure difference between the liquid supply pipe (2) side and the air outlet pipe (3) side is used to push the cooling medium to flow.

2. The self-circulating evaporation cooling system without a pump for the rotor of a vertical hydro-generator according to claim 1, characterized in that, The inlet of the cooling channel is communicated with the outlet of an insulating liquid infusion pipe (5) through a liquid inlet joint (4), and the outlet of the liquid supply pipe (2) is communicated with the inlet of the insulating liquid infusion pipe (5).

3. A self-circulating evaporation cooling system without a pump for the rotor of a vertical hydrogenerator according to claim 2, characterized in that, The outlet of the cooling channel is communicated with the inlet of an insulating gas transmission pipe (7) through a liquid outlet joint (6), and the inlet of the air outlet pipe (3) is communicated with the outlet of the insulating gas transmission pipe (7).

4. A self-circulating evaporation cooling system without a pump for a vertical hydrogenerator rotor according to claim 3, characterized in that, A liquid-side electrical joint (8) is connected to the liquid inlet joint (4), and a gas-side electrical joint (9) is connected to the liquid outlet joint (6).

5. The self-circulating evaporation cooling system without a pump for the rotor of a vertical hydrogenerator according to claim 3, characterized in that, The cooling pipeline further includes: a liquid distribution ring pipe (10) and a gas distribution ring pipe (11) arranged in parallel inside the rotor, the outlet of the liquid supply pipe (2) is communicated with the liquid distribution ring pipe (10), and the inlet of the insulating liquid infusion pipe (5) is communicated with the liquid distribution ring pipe (10); The inlet of the air outlet pipe (3) is communicated with the gas distribution ring pipe (11), and the outlet of the insulating gas transmission pipe (7) is communicated with the gas distribution ring pipe (11).

6. The self-circulating evaporation cooling system without a pump for the rotor of a vertical hydrogenerator according to claim 5, characterized in that, The coil body (1) has multiple groups arranged circumferentially, and the inlets of the insulating liquid infusion pipes (5) of multiple groups of the coil bodies (1) are simultaneously communicated with the liquid distribution ring pipe (10); The outlets of the insulating gas transmission pipes (7) of multiple groups of the coil bodies (1) are simultaneously communicated with the gas distribution ring pipe (11).

7. The self - circulating evaporation cooling system without a pump for the rotor of a vertical hydro - generator according to claim 6, characterized in that, An insulating layer (12) is provided between adjacent coil bodies (1).

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