Water-turbine generator set based on phase change cooling

Abstract

The invention relates to the technical field of power generation, in particular to a water-turbine generator set based on phase change cooling, and aims to solve the problem that personal safety is endangered due to leakage of a phase change working medium of an existing water-turbine generator set. Therefore, the water-turbine generator set based on phase-change cooling comprises a machine base body, a phase-change cooling device, a phase-change cooling device and a phase-change cooling device, a phase change cooling system and an air cooler; the optical detection device comprises a light source and a receiver; the rotor assembly comprises a rotor support, an air inlet hole is formed in the rotor support, when the water-turbine generator set operates, air flow sequentially flows through the stator assembly and the air cooler and then enters the rotor assembly through the air inlet hole to form a gas circulation loop, and a light path formed by the light source and the receiver intersects with the gas circulation loop. Therefore, the optical detection device can detect gas components in the gas flow. The gas components in the gas circulation loop in the generator set are detected based on the optical detection technology, and the reliability and accuracy of the detection result are higher.

Description

Technical Field

[0001] The present application relates to the technical field of power generation, and specifically provides a hydro-turbine generator set based on phase change cooling. Background Art

[0002] A hydroelectric generator is a generator that uses a water turbine as the prime mover to convert water energy into electrical energy. During the operation of a hydroelectric generator, its internal functional components, such as the stator bars, the excitation winding on the rotor, and the brushes and collector rings of the generator, will continuously generate heat. At the same time, the rotor will also generate heat due to mechanical friction and air friction during rotation. Therefore, the generator needs to be cooled in time during operation to ensure the normal operation of the generator.

[0003] At present, the evaporative cooling water turbine generators in operation rely on the vaporization latent heat of phase change working fluid to carry away heat. Phase change working fluid has the advantages of high insulation, non-toxic and non-corrosive, and it relies on the pressure difference generated during the vaporization process of phase change working fluid to achieve self-circulation, overcoming the problems of high operating pressure of traditional water cooling system and leakage that easily causes short circuit of electrical components. However, during the operation of the generator, the phase change working fluid will inevitably leak. Although a small amount of gaseous working fluid leakage will not cause obvious harm to the human body, the water turbine generator is installed in a confined space, and the specific gravity of the gaseous working fluid is much greater than that of the air. Therefore, when the working fluid continues to leak, the leaked working fluid will gradually sink in the above-mentioned confined space and accumulate to the bottom of the machine pit, which may cause hypoxia of the workers and endanger their personal safety.

[0004] Accordingly, the art needs a new technical solution to solve the above problems. Summary of the invention

[0005] The present application aims to solve the above technical problem, that is, to solve the problem that the existing hydro-generator sets endanger personal safety due to continuous leakage of phase-change working fluid.

[0006] To this end, the present application provides a hydro-generator set based on phase change cooling, which comprises:

[0007] A machine base body, a closed space is formed inside the machine base body, and a stator assembly and a rotor assembly are arranged inside the machine base body;

[0008] A phase change cooling system for cooling the stator assembly;

[0009] An air cooler, which is arranged on the outer side of the stator assembly along the radial direction of the hydro-generator set;

[0010] An optical detection device comprising a light source and a receiver opposite to the light source;

[0011] Wherein, the rotor assembly includes a rotor bracket, and the rotor bracket has an air inlet. When the hydro-turbine generator set is in operation, the airflow flows through the stator assembly and the air cooler in sequence and then enters the rotor assembly through the air inlet to form a gas circulation loop. The optical path formed by the light source and the receiver intersects with the gas circulation loop, so that the optical detection device can detect the gas components in the airflow.

[0012] In a technical solution of the above-mentioned hydro-turbine generator set, the air inlet includes an upper air inlet and a lower air inlet which are arranged axially opposite to each other along the rotor support, the gas circulation loop includes a first area surrounding the outer sides of the upper air inlet and the lower air inlet, and the light source and the receiver are respectively located on different sides of the first area so that the light path can pass through the upper air inlet and the lower air inlet.

[0013] In a technical solution of the above-mentioned hydro-turbine generator set, the gas circulation loop includes a second area located radially outside the air cooler along the hydro-turbine generator set, and the light source and the receiver are respectively located on different sides of the second area so that the light path can pass through the second area.

[0014] In one technical solution of the above-mentioned hydro-generator set, the optical detection device further comprises:

[0015] A condenser lens is disposed close to the receiver.

[0016] In a technical solution of the above-mentioned hydro-generator set, the focus of the condenser lens is located on the light incident surface of the receiver.

[0017] In a technical solution of the above-mentioned hydro-generator set, the light source, the focusing lens and the receiver are located on the same straight line.

[0018] In a technical solution of the above-mentioned hydro-generator set, the straight line is parallel to the axis of the hydro-generator set.

[0019] In a technical solution of the above-mentioned hydro-turbine generator set, the light source is arranged on the frame or bearing of the hydro-turbine generator set; and / or

[0020] The receiver is arranged on the frame or the bearing of the water turbine unit.

[0021] In a technical solution of the above-mentioned hydro-generator set, a plurality of the upper air inlet holes and the lower air inlet holes are arranged in a circumferential array along the rotor bracket.

[0022] In a technical solution of the above-mentioned hydro-generator set, the upper air inlet hole and the lower air inlet hole are both arc-shaped holes.

[0023] As mentioned above, in the case of adopting the above technical solution, the present application detects the gas composition in the internal gas circulation loop of the hydro-turbine generator set during its operation based on optical detection technology, so as to determine whether there is a working fluid leakage in the whole machine. The detection method has strong anti-interference ability and can be stably applied in the complex electromagnetic environment of the generator set. Moreover, compared with the method of sampling and detecting the internal ambient airflow of the generator set in the prior art, the present application combines the air cooling principle of the generator set to detect the airflow in its gas circulation loop in a targeted manner, and the reliability and accuracy of the detection results are higher. At the same time, the present application uses an optical detection device to perform single-point detection on a local position in the gas circulation loop, which can reflect the leakage of the gaseous working fluid in the whole machine, which can also simplify the system structure and reduce equipment costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings, in which:

[0025] Figure 1 is a longitudinal cross-sectional view of a hydro-generator set based on phase change cooling according to an embodiment of the present application;

[0026] Figure 2 It is a schematic diagram showing the airflow circulation path within a hydro-turbine generator set.

[0027] In the figures, the reference numerals refer to the following:

[0028] 1. stator assembly; 2. rotor assembly; 21. rotating shaft; 22. rotor bracket; 221. upper air inlet; 222. lower air inlet; 3. phase change cooling system; 4. air cooler; 5. optical detection device; 51. light source; 52. receiver; 53. focusing lens;

[0029] 100, first area; 101, lower bearing; 102, upper frame; 103, lower frame; 104, upper bearing; 200, second area; 300, optical path. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present application are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present application and are not used to limit the scope of protection of the present application. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.

[0031] It should be noted that in the description of this application, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description, and does not indicate or imply that the relevant devices or components must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on this application. In addition, the ordinal numbers "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0032] In addition, it should be noted that in the description of this application, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] In order to facilitate understanding of the technical solution of the present application, the cooling principle of the hydro-turbine generator set is briefly introduced first. When the hydro-turbine generator set is cooled based on phase change liquid cooling, its cooling is reflected in two aspects: one is the cooling of the stator winding by the phase change cooling system, and the other is the cooling of the rotor and necessary components such as brushes and collector rings by the air cooler, that is, the cooling of the hydro-turbine generator set is usually a combination of phase change cooling and air cooling.

[0034] In some related technologies, in order to detect the leakage of phase-change working fluids and ensure the safety of the project, a gas sampling box is installed inside the generator to detect the gas inside the generator to determine the leakage amount of the gaseous working fluid, and when the leakage amount is large, the gaseous working fluid is absorbed and processed to ensure the safe operation of the generator set. However, the high-speed circulating airflow in the generator set will dilute the gaseous working fluid, so it can only be detected when the content of the leaked working fluid is high enough. Therefore, the airflow circulation in the generator set will interfere with the detection process. The above method is difficult to achieve accurate detection of the content of the leaked working fluid. In order to improve the detection accuracy, the above detection device needs to set up enough sampling systems (including sampling boxes and sampling air pumps) to perform multi-point detection, which will greatly increase the complexity of the system.

[0035] It can be seen that although the above method can perform corresponding detection on whether the working fluid is leaking, it still has significant disadvantages.

[0036] Reference Figure 1, is a hydro-turbine generator set based on phase change cooling according to an embodiment of the present application, which includes a base body (not fully shown in the figure), a stator assembly 1, a rotor assembly 2, a phase change cooling system 3, an air cooler 4 and other necessary functional components, and an optical detection device 5 arranged in the base body.

[0037] The base body serves as the installation base for the above-mentioned functional components of the generator set. It is mainly used to support and fix the above-mentioned stator assembly 1, rotor assembly 2, end cover and other components. A closed space is formed inside the base body. The stator assembly 1 includes components such as an iron core and a stator winding. The rotor assembly 2 includes a rotating shaft 21, a rotor bracket 22, and components such as a yoke, a magnetic pole, and a collector. Of course, the functional components of the above-mentioned generator set are all well-known technologies in the art. The above-mentioned functional components are introduced here only for the convenience of describing the technical solution of the present application. The detailed structure of each functional component in the generator set and the connection relationship between each part are not described in detail in this application.

[0038] The phase change cooling system 3 is used to cool the wire rods in the stator assembly 1. The air cooler 4 is arranged on the radial outer side of the stator assembly 1. The phase change cooling system 3 and the air cooler 4 are also well-known technologies in the art, and the specific structure thereof will not be described in detail in this application.

[0039] Reference Figure 1 and Figure 2 The optical detection device 5 includes a light source 51 and a receiver 52. The receiver 52 is arranged opposite to the light source 51 and is used to receive the light emitted by the light source. The rotor bracket 22 has an air inlet. Specifically, the air inlet includes an upper air inlet 221 and a lower air inlet 222. The upper air inlet 221 and the lower air inlet 222 are arranged opposite to each other along the axial direction of the rotor bracket 22. Therefore, during the rotation of the rotor assembly 2, the airflow in the rotor assembly 2 can move radially outward under the action of centrifugal force, and successively pass through the yoke ventilation duct, the pole-to-pole gap and the air gap of the stator assembly 1 of the rotor assembly 2, and finally pass through the air cooler 4. The cooled airflow passing through the air cooler 4 is blocked by the side wall of the machine pier or the machine base body and moves to both sides along the axial direction of the generator set. Then, under the action of the pressure difference (the central area of ​​the generator set, that is, the air inlet position of the rotor bracket 22 is low pressure), it flows radially inward again to the air inlet position of the rotor bracket 22, thus forming a gas circulation loop ( Figure 1 The arrow in the middle shows the flow direction of the airflow, i.e., the gas circulation loop). In the process of the airflow circulating back and forth through the air cooler 4, the heat is taken away to the outside by the cold source in the air cooler, thereby achieving heat exchange. For large-scale hydro-generator sets, the air cooling method is usually the above-mentioned radial ventilation or axial radial mixed ventilation method.

[0040] The light source 51 and the receiver 52 are respectively located on different sides of the rotor support 22, and the light source 51 and the receiver 52 can be installed on the frame or bearing of the hydro-generator set. Figure 1 In an exemplary embodiment shown, the light source 51 is mounted on the lower bearing 101, and the receiver 52 is mounted on the upper frame 102. It should be noted that the specific installation positions of the light source 51 and the receiver 52 can be determined according to the specific spatial layout in the hydro-turbine generator set. For example, when the lower bearing 101 is a guide bearing, its diameter is relatively small, and the light source 51 can be installed on the lower frame 103; when the upper bearing 104 is a thrust bearing, its diameter is relatively large, and the receiver 52 can be installed on the upper bearing 104. In short, both the light source 51 and the receiver 52 can be installed on the frame or bearing on any side of the rotor bracket 22. It should be understood that those skilled in the art can adaptively adjust the installation positions of the light source 51 and the receiver 52 according to actual needs, which does not constitute a limitation to the present application.

[0041] Reference Figure 2 The gas circulation loop includes a first area 100 (the dotted box on the left side of the figure) surrounding the outer side of the upper air inlet hole 221 and the lower air inlet hole 222. The light source 51 and the receiver 52 are respectively located on different sides of the first area 100 in the axial direction of the hydro-turbine generator set, so that the light path 300 formed by the light source 51 and the receiver 52 can pass through the upper air inlet hole 221 and the lower air inlet hole 222.

[0042] As can be seen from the above, when the hydro-turbine generator set is in operation, the formation of the gas circulation loop comes from the centrifugal force during the rotation of the rotor assembly 2. Under the action of the centrifugal force, the airflow inside the rotor assembly 2 moves radially outward, and under the action of the pressure difference, it flows back to the rotor bracket 22 through the upper air inlet hole 221 and the lower air inlet hole 222 of the rotor bracket 22. Therefore, in the entire gas circulation loop, the upper air inlet hole 221 and the lower air inlet hole 222 and the interior of the rotor bracket 22 define a narrow channel for airflow to pass through. Therefore, the airflow is most concentrated in the area near the upper air inlet hole 221 and the lower air inlet hole 222 (i.e., the above-mentioned first area 100). When the working fluid in the phase change cooling system 3 of the hydro-turbine generator set leaks, the gaseous working fluid after phase change mixes with the air to form the above-mentioned airflow. The airflow must flow through the above-mentioned first area 100 during the circulation process. It is obviously more reliable to detect the first area 100 where the airflow is most concentrated by the optical detection device 5.

[0043] During the operation of the hydro-turbine generator set, the optical detection device 5 is in an on state, and the light emitted by the light source 51 passes through the air inlet of the rotor bracket 22. During this process, the receiver 52 performs optical characteristic analysis on the light received, thereby detecting the gas components in the airflow in the gas circulation loop, thereby determining whether there is a working fluid leakage in the generator set.

[0044] It should be noted that the optical detection device 5 described above detects the composition and concentration of the gaseous working fluid by utilizing the absorption, scattering or refraction characteristics of the airflow to light, which is a well-known technology in the art. For example, based on the absorption spectrum principle, when the light emitted by the light source 51 irradiates the airflow, different gas components in the airflow will absorb light of a specific wavelength, resulting in a decrease in light intensity. If the gas component in the airflow is only air, or the gas component in the airflow includes a mixed gas of air and gaseous working fluid, it is obvious that the spectrum generated by the receiver 52 is different, and the spectrum reflects the change in light intensity. When the leakage of the gaseous working fluid is more serious and the concentration is higher, the change is more obvious, so that the gas component in the airflow and the concentration value of the gaseous working fluid can be judged.

[0045] As mentioned above, this application is based on optical detection technology to detect the gas composition in the internal gas circulation loop of the hydro-turbine generator set during its operation, so as to determine whether there is a working fluid leakage in the whole machine. The detection method has strong anti-interference ability and can be stably applied in the complex electromagnetic environment of the generator set. Moreover, compared with the method of sampling and detecting the internal ambient airflow of the generator set in the prior art, this application combines the air cooling principle of the generator set to detect the airflow in its gas circulation loop in a targeted manner, and the reliability and accuracy of the detection results are higher. At the same time, this application uses an optical detection device 5 to perform single-point detection on a local position in the gas circulation loop, which can reflect the leakage of the gaseous working fluid in the whole machine, which can also simplify the system structure and reduce equipment costs.

[0046] In one embodiment of the present application, a plurality of upper air inlet holes 221 and lower air inlet holes 222 are arranged in a circumferential array along the rotor bracket 22, and the upper air inlet holes 221 and the lower air inlet holes 222 correspond to each other in the axial direction of the rotor bracket 22. Since the rotor bracket 22 is in a reciprocating rotation state, during the detection process of the optical detection device 5, the rotor bracket 22 will block the optical signal generated by the light source 51, resulting in the optical signal detected by the receiver 52 being intermittent, and the upper air inlet holes 221 and the lower air inlet holes 222 are arranged in a plurality along the circumference of the rotor bracket 22, which is not only conducive to the formation of a gas circulation loop and improves the air cooling efficiency, but also can improve the phenomenon of the rotor bracket 22 blocking the optical signal.

[0047] Furthermore, the upper air inlet hole 221 and the lower air inlet hole 222 are configured as arc holes, and the arc track of the arc hole extends along the circumference of the rotor bracket 22. Setting the upper air inlet hole 221 and the lower air inlet hole 222 as arc holes is conducive to improving the continuity of the optical signal, making the spectrum generated by the receiver 52 more intuitive, which is conducive to gas component analysis.

[0048] Reference Figure 2The gas circulation loop includes a second area 200 located radially outside the air cooler 4 of the hydro-generator set, that is, the second area 200 is located between the air cooler 4 and the machine pier. After the airflow from the rotor support 22 passes through the air cooler 4 in the radial direction, it turns in the second area 200 (moves axially to the upper and lower sides), so the airflow in the second area 200 is relatively concentrated. Based on this, in one embodiment of the present application, the light source 51 and the receiver 52 are respectively arranged on the upper and lower sides of the second area 200, so that the above-mentioned optical path 300 can pass through the second area 200 and detect the gas composition of the airflow in the second area 200.

[0049] It should be noted that the attached drawing of the present application is a longitudinal cross-sectional view of a hydro-turbine generator set, and therefore the first area 100 and the second area 200 appear as rectangular areas in the drawing, but in fact the first area 100 and the second area 200 are both annular spaces formed by rotating the rectangular area in the drawing 360°, but the optical detection device 5 only needs to be arranged in one of the longitudinal cross-sections of the annular space.

[0050] It should also be noted that, for the above-mentioned first area 100 and second area 200, they are two areas where the airflow density is relatively concentrated in the entire gas circulation loop of the generator set. In the actual size design of the generator set, the radial size of the air inlet of the rotor bracket 22 is usually small, so that the radial size of the first area 100 is small, presenting a relatively narrow airflow channel, while the outer side of the air cooler 4, that is, the second area 200, is restricted by factors such as engineering maintenance and usually presents a relatively large radial size, so that the gyration radius of the second area 200 is greater than the gyration radius of the first area 100. On the other hand, the airflow in the first area 100 is affected by the pressure difference, the airflow speed is faster, and the airflow is denser, while the airflow within the second area 200 is blocked by the machine pier, and the gas molecules present a relatively irregular movement path.

[0051] Therefore, in combination with the internal spatial layout of the generator set and the characteristics of airflow movement, the airflow in the first area 100 is more concentrated than that in the second area 200, and the concentration detection of the gaseous working medium in the airflow in the first area 100 is more valuable for reference. However, there are no obstructions on the upper and lower sides of the second area 200, while the first area 100 will be intermittently obstructed by the rotor bracket 22. In practical applications, those skilled in the art can choose to install the optical detection device 5 in any of the above areas according to their needs, and this application does not limit this.

[0052] Although in the above-mentioned embodiments of the present application, the first area 100 and the second area 200 are used as examples for illustrative description as the areas through which the light path 300 passes, this does not constitute a limitation to the present application. In some other embodiments, as long as the light path 300 formed by the light source 51 and the receiver 52 can intersect with the gas circulation loop, the light emitted by the light source 51 can pass through the gas circulation loop, and the composition of the gas in the airflow can be detected.

[0053] Reference Figure 1 and Figure 2 In one embodiment of the present application, the optical detection device 5 also includes a focusing lens 53, which is arranged close to the receiver 52. The focusing lens 53 is used to converge the light emitted by the light source 51, reduce the amount of light scattered to the surroundings during the propagation of the light along the optical path 300, thereby improving the light intensity, which is more conducive to analyzing the gas components in the airflow. The focusing lens 53 can be fixed to a frame, a bearing or other position by a bracket structure, etc., and the present application does not limit this. Optionally, when the focusing lens 53 is installed, the distance between the focusing lens 53 and the receiver 52 can be adjusted so that the focus of the focusing lens 53 is located on the light incident surface of the receiver 52 to maximize the intensity of the optical signal.

[0054] In one implementation, the light source 51, the focusing lens 53, and the receiver 52 are located on the same straight line, which can shorten the length of the optical path, reduce light loss, and improve the quality of the optical signal.

[0055] Furthermore, the straight line formed by the light source 51, the focusing lens 53 and the receiver 52 (i.e., the trajectory of the optical path 300) is parallel to the axis of the hydro-generator set. Since the optical detection device 5 is installed in the first area 100 or the second area 200, the first area 100 and the second area 200 are both rectangular areas, when the straight line trajectory of the optical path 300 is parallel to the axial direction of the hydro-generator set, more airflow can pass through, thereby improving the reliability and accuracy of gas component analysis.

[0056] Finally, it should be noted that the light source 51 of the present application can be an ordinary light source or a laser, and the light source 51 can be a single point light source or a light source array composed of multiple point light sources. The focusing lens 53 can be a convex lens or a Fresnel lens, a single lens or a lens array composed of multiple lenses. In short, the present application does not limit the specific type, quantity and arrangement of the light source 51 and the focusing lens 53, and those skilled in the art can make adaptive adjustments according to actual needs, and such adjustments are all within the protection scope of the present application.

[0057] So far, the technical solutions of the present application have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. A hydro-generator set based on phase change cooling, characterized in that: include: A machine base body, the interior of which forms a closed space, wherein the machine base body contains a stator assembly (1) and a rotor assembly (2); A phase change cooling system (3) for cooling the stator assembly (1); An air cooler (4) is arranged on the outer side of the stator assembly (1) along the radial direction of the hydro-generator set; An optical detection device (5), comprising a light source (51) and a receiver (52) opposite to the light source (51); The rotor assembly (2) comprises a rotor support (22), and the rotor support (22) has an air inlet. When the hydro-turbine generator set is in operation, the airflow flows through the stator assembly (1) and the air cooler (4) in sequence and then enters the rotor assembly (2) through the air inlet, thereby forming a gas circulation loop. The optical path (300) formed by the light source (51) and the receiver (52) intersects with the gas circulation loop, so that the optical detection device (5) can detect the gas components in the airflow.

2. The hydro-generator set according to claim 1, characterized in that: The air inlet hole comprises an upper air inlet hole (221) and a lower air inlet hole (222) which are arranged axially opposite to each other along the rotor support (22); the gas circulation loop comprises a first area (100) surrounding the outer sides of the upper air inlet hole (221) and the lower air inlet hole (222); the light source (51) and the receiver (52) are respectively located on different sides of the first area (100) so that the optical path (300) can pass through the upper air inlet hole (221) and the lower air inlet hole (222).

3. The hydro-generator set according to claim 1, characterized in that: The gas circulation loop comprises a second region (200) located radially outside the air cooler (4) of the hydro-generator set, and the light source (51) and the receiver (52) are respectively located on different sides of the second region (200) so that the optical path (300) can pass through the second region (200).

4. The hydro-generator set according to claim 2 or 3, characterized in that: The optical detection device (5) further comprises: A condenser lens (53) is arranged close to the receiver (52).

5. The hydro-generator set according to claim 4, characterized in that: The focal point of the condenser lens (53) is located on the light incident surface of the receiver (52).

6. The hydro-generator set according to claim 4, characterized in that: The light source (51), the focusing lens (53) and the receiver (52) are located on the same straight line.

7. The hydro-generator set according to claim 6, characterized in that: The straight line is parallel to the axis of the hydro-generator set.

8. The hydro-generator set according to claim 2, characterized in that: The light source (51) is arranged on the frame or bearing of the water turbine unit; and / or The receiver (52) is arranged on the frame or the bearing of the water turbine unit.

9. The hydro-generator set according to claim 2, characterized in that: A plurality of the upper air inlet holes (221) and the lower air inlet holes (222) are arranged in a circumferential array along the rotor support (22).

10. The hydro-generator set according to claim 9, characterized in that: The upper air inlet hole (221) and the lower air inlet hole (222) are both arc-shaped holes.

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