Steam turbine generator ventilation cooling system with fully oil-cooled stator and press-in and withdraw-out staggered rotor

Abstract

The present invention discloses a steam turbine generator ventilation and cooling system with a fully oil-cooled stator and a press-in / extract staggered rotor, which relates to the field of electric motors. To address the high temperature problem of existing large-capacity steam turbine generators, the present invention provides a stator axial oil channel within the stator core, a stator sealed oil shroud wraps around the outside of the entire stator area, and the stator sealed oil shroud is filled with flowing cooling oil. An oil cooler is mounted above the stator bracket, an extractable multi-stage fan and a press-in multi-stage fan are mounted on either side of the rotor shaft, and a gas cooler is mounted on the air inlet side of the press-in multi-stage fan. The rotor main shaft and rotor secondary shaft are connected, and fan plates are evenly mounted circumferentially on the outer surface of the rotor secondary shaft. The rotor core is provided with rotor radial ventilation grooves and rotor axial ventilation holes, which are connected via a rotor axial air guide ring. The present invention enhances the cooling effect of steam turbine generator components and has a simple structure, making it easy to implement.

Description

Technical Field

[0001] The invention relates to a ventilation and cooling system for a steam turbine generator with a full oil-cooled stator and a press-in and withdraw-out staggered rotor, belonging to the field of motors. Background Art

[0002] With the continuous advancement of science and technology, electric energy has become one of the important power sources and material foundations necessary for social development and people's lives. The emergence and application of steam turbine generators have brought many conveniences to our production and life, met people's growing demand for electricity, and had a very important impact on human production, life and sustainable development. Steam turbine generators are one of the key equipment in thermal power plants, combined cycle power plants and nuclear power plants. As an important energy conversion device in power plants, excessive internal temperature and short circuit faults of steam turbine generators will directly affect the reliability of the unit's operation. Once a fault occurs, it will not only have a serious impact on the safe operation of the power plant generator and even the power system, but also cause huge economic losses.

[0003] To effectively increase the total fluid flow rate within the turbine generator and fully utilize the cooling medium within the turbine generator to effectively remove heat from various components, a turbine generator ventilation cooling system with a fully oil-cooled stator and a staggered, press-in / extract rotor can be used. Multiple rows of axial oil channels within the stator core and the use of cooling oil as the cooling medium effectively remove heat from the stator end windings, stator pressure fingers, stator pressure plates, and stator core, significantly reducing the temperatures of these stator end windings, stator pressure fingers, stator pressure plates, and stator core. This effectively addresses the difficulty in effectively cooling the stator region of large turbine generators. The use of a multi-stage, pull-out fan and a multi-stage, press-in fan, radial ventilation grooves and axial ventilation holes within the rotor core, and a fan plate on the outer surface of the rotor countershaft accelerate the flow of cooling gas through the rotor core and rotor windings, improving the circulation speed of the rotor ventilation system, significantly reducing the temperatures of the rotor core and rotor windings, and enhancing the safe and stable operation of the turbine generator. Summary of the Invention

[0004] The purpose of the present invention is to provide a ventilation and cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in and withdrawn staggered rotor, so as to solve the problem of excessive temperature of the stator core, stator winding, rotor core, rotor winding and end components caused by unreasonable ventilation design of the stator area and rotor area of ​​a large-capacity steam turbine generator, change the cooling medium in the stator area, enhance the flow velocity of the fluid in the rotor area, and improve the heat dissipation efficiency of the steam turbine generator. Through the ventilation and cooling system with a fully oil-cooled stator and a press-in and withdrawn staggered rotor, the maximum temperature of each component in the steam turbine generator can be effectively reduced, thereby improving the ability of the steam turbine generator to operate safely and stably for a long time.

[0005] The ventilation and cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in / extract staggered rotor comprises an oil cooler, a stator core, a sealed stator oil cover, a stator axial oil channel, stator pressure fingers, a stator pressure plate, stator windings, a stator bracket, a rotor core, rotor radial ventilation grooves, rotor axial ventilation holes, a rotor axial air guide ring, an extractable multi-stage fan, a press-in multi-stage fan, a rotor shaft, a fan plate, rotor windings, a gas cooler, and a housing. The stator core comprises stator core teeth and a stator core yoke; the rotor shaft comprises a rotor main shaft and a rotor secondary shaft. A stator axial oil channel is provided in the stator core, a stator sealed oil cover is wrapped around the outside of the entire stator area, the stator sealed oil cover is filled with flowing cooling oil, an oil cooler is installed above the stator bracket, an extraction type multi-stage fan and a push-in type multi-stage fan are installed on both sides of the rotor shaft respectively, a gas cooler is installed on the air inlet side of the push-in type multi-stage fan, the rotor main shaft and the rotor secondary shaft are connected, the fan plates are evenly installed on the outer surface of the rotor secondary shaft along the circumferential direction, a rotor radial ventilation groove and a rotor axial ventilation hole are provided in the rotor core, and the rotor axial ventilation holes are connected through a rotor axial air guide ring.

[0006] The radius of the stator axial oil channel is 5mm to 15mm; the inner diameter of the stator sealed oil cover is equal to the inner diameter of the stator core, and the outer diameter of the stator sealed oil cover is equal to the inner diameter of the oil cooler; the cross-section of the rotor axial ventilation hole is circular, with a radius of 5mm to 20mm; the inner diameter of the rotor axial air guide ring is equal to the outer diameter of the rotor axial ventilation hole; the width of the rotor radial ventilation groove is 5mm to 20mm; a fan plate is installed on the rotor secondary shaft, and there are 5 to 8 fan plates in the circumferential direction.

[0007] Preferably, the stator axial oil channel is adjusted from a linear arrangement to a serpentine arrangement, which reduces the number of openings in the stator pressure plate and the stator pressure finger, increases the contact area between the stator core and the cooling oil, and effectively reduces the temperature of the stator core.

[0008] Preferably, the rotor core teeth are provided with a row of rotor axial ventilation holes, which increases the surface heat dissipation coefficient of the rotor core teeth, effectively takes away the heat of the rotor core teeth, and further reduces the temperature of the rotor core.

[0009] Preferably, the stator axial oil channels are adjusted to be staggered in the circumferential direction, thereby improving the utilization rate of the cooling oil in the stator axial oil channels, cooling the stator core more fully, and further reducing the temperature of the stator core.

[0010] Advantages of the present invention: The stator core, stator winding, rotor core, rotor winding and end components in a large-capacity steam turbine generator generate relatively serious heat. The present invention adopts an extraction-type multi-stage fan and a push-in-type multi-stage fan on both sides of the steam turbine generator, adopts cooling oil as a cooling medium in the stator area, provides multiple rows of regular stator axial oil channels on the stator teeth and yoke, provides rotor radial ventilation grooves and rotor axial ventilation holes in the rotor core, adopts a rotor main shaft and a rotor secondary shaft combination in the rotor shaft, and adds a fan plate on the outer surface of the rotor secondary shaft, thereby forming a steam turbine generator ventilation cooling system with a fully oil-cooled stator and a push-in-extraction staggered rotor. The ventilation cooling system for a steam turbine generator with a fully oil-cooled stator and a staggered, press-in, press-out rotor utilizes cooling oil as the cooling medium in the stator region. Multiple rows of regular stator axial oil channels are provided in the stator teeth and yoke, effectively removing heat from the stator end windings, stator pressure fingers, stator pressure plates, and stator core. This increases the contact area between the cooling oil and these components, significantly reducing their temperatures. This resolves the difficulty in effectively cooling the stator region of large steam turbine generators and significantly reduces the temperature of severely heated stator windings. Regarding ventilation cooling in the rotor region, both pull-out and press-in multi-stage fans are employed on both sides of the turbine generator. These fans significantly increase the flow rate and pressure of the cooling gas within the turbine generator. By providing radial ventilation grooves and axial ventilation holes within the rotor core and adding a fan plate to the outer surface of the rotor secondary shaft, the speed of cooling gas passing through the rotor core and rotor windings is effectively increased, reducing the temperature of the rotor core and rotor windings, and increasing the circulation speed of the rotor ventilation system. This solves the problem of air paths interfering with each other within the rotor core, improves the insufficient cooling capacity of traditional air-cooled structures, reduces the axial temperature difference and thermal stress in the turbine generator rotor region, and enhances the turbine generator's ability to operate safely and stably. The turbine generator ventilation system with a fully oil-cooled stator and a press-in / extract staggered rotor, as described in the present invention, significantly outperforms conventional turbine generator ventilation systems in cooling performance. Furthermore, it offers lower manufacturing costs, higher reliability, and greater ease of implementation than conventional turbine generators. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] For ease of explanation, the present invention is described in detail with reference to the following specific implementations and accompanying drawings.

[0012] Figure 1 This is an axial cross-sectional view of the ventilation and cooling system of the steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to the present invention.

[0013] Figure 2This is a partial enlarged view of the radial cross section of the stator core in the ventilation cooling system of the steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to the present invention.

[0014] Figure 3 This is a partial enlarged view of the radial cross section of the rotor core in the ventilation cooling system of the steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to the present invention.

[0015] Figure 4 The figure is an axial cross-sectional view of a rotor axial air guide ring in a ventilation and cooling system of a steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to the present invention.

[0016] Figure 5 The present invention provides a radial cross-sectional view of a rotor axial air guide ring in a ventilation and cooling system for a steam turbine generator having a fully oil-cooled stator and a press-in / extract staggered rotor.

[0017] Figure 6 The present invention provides a radial cross-sectional view of a stator sealed oil cover and an oil cooler in a ventilation cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in / extract staggered rotor.

[0018] Figure 7 This is an axial cross-sectional view of a ventilation and cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to a second specific embodiment of the present invention.

[0019] Figure 8 This is an axial cross-sectional view of a ventilation and cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to a third specific embodiment of the present invention.

[0020] Figure 9 This is a partial enlarged view of the radial cross section of the stator core in the ventilation cooling system of the steam turbine generator with a full oil-cooled stator and a press-in and withdrawable staggered rotor according to the fourth specific embodiment of the present invention.

[0021] In the diagram: 1 - oil cooler, 2 - stator core, 3 - stator sealed oil cover, 4 - stator axial oil channel, 5 - stator pressure finger, 6 - stator pressure plate, 7 - stator winding, 8 - stator bracket, 9 - rotor core, 10 - rotor radial ventilation groove, 11 - rotor axial ventilation hole, 12 - rotor axial air guide ring, 13 - extraction multi-stage fan, 14 - push-in multi-stage fan, 15 - rotor shaft, 16 - fan plate, 17 - rotor winding, 18 - gas cooler, 19 - casing. The arrows in the diagram indicate the direction of coolant flow in the ventilation cooling system of a steam turbine generator with a fully oil-cooled stator and a staggered pull-in / extraction rotor. DETAILED DESCRIPTION

[0022] Specific implementation method 1: Combination Figures 1 to 6This embodiment describes a steam turbine generator ventilation and cooling system with a fully oil-cooled stator and a press-in / extract staggered rotor. The system comprises an oil cooler 1, a stator core 2, a stator sealed oil cover 3, a stator axial oil channel 4, a stator pressure finger 5, a stator pressure plate 6, a stator winding 7, a stator bracket 8, a rotor core 9, rotor radial ventilation grooves 10, rotor axial ventilation holes 11, a rotor axial air guide ring 12, an extractable multi-stage fan 13, a press-in multi-stage fan 14, a rotor shaft 15, a fan plate 16, a rotor winding 17, a gas cooler 18, and a housing 19. The stator core 2 includes stator core teeth 2-1 and a stator core yoke 2-2. The rotor shaft 15 consists of a rotor main shaft 15-1 and a rotor secondary shaft 15-2. A stator axial oil channel 4 is provided in the stator core 2, a stator sealed oil cover 3 is wrapped around the outside of the entire stator area, the stator sealed oil cover 3 is filled with flowing cooling oil 20, the oil cooler 1 is installed above the stator bracket 8, the extraction type multi-stage fan 13 and the push-in type multi-stage fan 14 are respectively installed on both sides of the rotor shaft 15, the gas cooler 18 is installed on the air inlet side of the push-in type multi-stage fan 14, the rotor main shaft 15-1 and the rotor secondary shaft 15-2 are connected, the fan plate 16 is evenly installed on the outer surface of the rotor secondary shaft 15-2 along the circumferential direction, the rotor core 9 is provided with a rotor radial ventilation groove 10 and a rotor axial ventilation hole 11, and the rotor axial ventilation hole 11 is connected through a rotor axial air guide ring 12.

[0023] The radius of the stator axial oil channel 4 is 5mm to 15mm, and the radius is 10mm in this embodiment; the inner diameter of the stator sealed oil cover 3 is equal to the inner diameter of the stator core 2, and the outer diameter of the stator sealed oil cover 3 is equal to the inner diameter of the oil cooler 1; the cross-section of the rotor axial ventilation hole 11 is circular, with a radius of 5mm to 20mm, and the radius is 15mm in this embodiment; the inner diameter of the rotor axial air guide ring 12 is equal to the outer diameter of the rotor axial ventilation hole 11; the width of the rotor radial ventilation groove 10 is 5mm to 20mm, and the width is 15mm in this embodiment; a fan plate 16 is installed on the rotor secondary shaft 15-2, and there are 5 to 8 fan plates 16 in the circumferential direction, and 8 in this embodiment.

[0024] The original single-sided multi-stage fan of the steam turbine generator is replaced with an exhaust-type multi-stage fan 13 and a push-in multi-stage fan 14 on both sides. The original stator area using hydrogen as the cooling medium and the stator copper winding having cooling water is replaced by the stator area using flowing oil for cooling. The original solid rotor core 9 is provided with rotor radial ventilation grooves 10 and rotor axial ventilation holes 11. The original solid rotor shaft is replaced with a rotor main shaft 15-1 and a rotor secondary shaft 15-2, and a fan plate 16 is added to the outer surface of the rotor secondary shaft 15-2. When the steam turbine generator ventilation cooling system with a full oil-cooled stator and a press-in and withdraw staggered rotor is in operation, the cooling oil flows out from the left end of the oil cooler 1 into the left cavity of the stator sealed oil cover 3 under the action of the driver. The cooling oil directly cools the left stator end winding, significantly increases the surface heat dissipation coefficient of the left stator end winding, and effectively reduces the temperature of the left stator end winding. After cooling the left stator end winding, the cooling oil enters the stator area in two ways. One way first passes through the left stator pressure finger 5 and the stator pressure plate 6 to enter the stator axial oil channel 4 in the stator core 2, and then passes through the stator pressure finger 5 and the stator pressure plate 6 to enter the right cavity of the stator sealed oil cover 3. This way of cooling oil can effectively take away the stator pressure finger 5, the stator pressure plate 6 and the stator. The heat of the core 2 increases the contact area between the cooling oil and the stator pressure finger 5, the stator pressure plate 6, and the stator core 2, significantly reducing the temperature of the stator pressure finger 5, the stator pressure plate 6, and the stator core 2. Another cooling oil flows axially on the outer surface of the stator core 2, passes through the stator bracket 8, and enters the right cavity of the stator sealed oil cover 3. This cooling oil can effectively increase the heat dissipation coefficient of the outer surface of the stator core 2 and effectively reduce the temperature of the stator core 2. The two cooling oils converge in the right cavity of the stator sealed oil cover 3, directly cooling the right stator end winding, significantly reducing the temperature of the right stator end winding. Finally, the heated cooling oil enters the oil cooler 1 from the right end for cooling, thereby completing the cooling cycle of the oil in the stator area. The strong heat dissipation capacity of the cooling oil can solve the problem of the difficulty in effectively cooling the stator area of ​​large steam turbine generators and significantly reduce the temperature of the stator winding 7, which is seriously heated. Within the rotor region, cooling gas, driven by the exhaust multi-stage fan 13 and the push-in multi-stage fan 14, first flows in from the right-side push-in multi-stage fan 14. After cooling the rotor end winding on the right side of the rotor region, one path of cooling gas enters the rotor axial ventilation holes 11 within the rotor core 9. This path of cooling gas flows axially, effectively removing heat from the rotor core 9 and rotor winding 17, lowering their temperatures and minimizing the axial temperature difference and thermal stress in the rotor region. Another path of cooling gas enters the air gap between the stator core 2 and the rotor core 9. This path of cooling gas flows axially, increasing the heat dissipation coefficient of the outer surface of the rotor core 9 and effectively reducing its temperature.In addition, a cooling gas stream, driven by the fan plate 16 on the outer surface of the rotor secondary shaft 15-2, flows radially into the rotor radial ventilation grooves 10. This increases the heat dissipation area between the cooling gas and the rotor core 9, effectively removing heat from the rotor core 9 and further reducing the temperature of the rotor core 9 and the rotor windings 17. This cooling gas stream flows out of the rotor radial ventilation grooves 10 and enters the air gap between the stator core 2 and the rotor core 9, then flows axially from right to left. These three cooling gas streams converge in the left side of the rotor area, cooling the left rotor end winding before entering the exhaust multi-stage fan 13. The heated gas extracted by the exhaust multi-stage fan 13 then flows through external circulation into the gas cooler 18 to the right of the pressure multi-stage fan 14. After being cooled by the gas cooler 18, the gas enters the pressure multi-stage fan 14, thus completing the circulation of the cooling gas within the rotor area. The cooling circulation in the stator area and the rotor area constitutes a ventilation cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in and pull-out staggered rotor. The ventilation cooling system effectively improves the cooling effect inside the steam turbine generator, directly removes the cooling water pipe inside the stator winding 7, reduces the manufacturing cost, effectively reduces the temperature of the stator end winding, the stator pressure finger 5, the stator pressure plate 6 and the stator core 2, increases the flow rate of the cooling gas in the rotor area, accelerates the fluid velocity around the rotor core 9 and the rotor winding 17, reduces the temperature of the rotor core 9 and the rotor winding 17, improves the utilization rate of the cooling gas in the rotor area of ​​the steam turbine generator, and enhances the ability of the steam turbine generator to operate safely and stably.

[0025] Specific implementation method 2: Combination Figure 7 This embodiment differs from the first embodiment in that the stator axial oil passages 4 are arranged in a serpentine pattern instead of a straight line. This reduces the number of openings in the stator pressure plate 5 and stator pressure fingers 6, increasing the contact area between the stator core 2 and the cooling oil, effectively reducing the temperature of the stator core 2. The remaining components and connections are the same as those in the first embodiment.

[0026] Specific implementation method three: Combination Figure 8 This embodiment differs from the first embodiment in that a row of rotor axial ventilation holes 11 is added to the teeth of the rotor core 9. This increases the surface heat dissipation coefficient of the teeth of the rotor core 9, effectively dissipating heat from the teeth of the rotor core 9 and further reducing the temperature of the rotor core 9. The remaining components and connections are the same as those of the first embodiment.

[0027] Specific implementation method four: Combination Figure 9This embodiment differs from the first embodiment in that the stator axial oil channels 4 are arranged in a staggered pattern in the circumferential direction. This improves the utilization rate of the cooling oil within the stator axial oil channels 4, allowing for more efficient cooling of the stator core 2 and further reducing the temperature of the stator core 2. The remaining components and connections are the same as those of the first embodiment.

[0028] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A steam turbine generator ventilation cooling system with a fully oil-cooled stator and a press-in / out staggered rotor, characterized by: The invention comprises an oil cooler (1), a stator core (2), a stator sealed oil cover (3), a stator axial oil channel (4), a stator pressure finger (5), a stator pressure plate (6), a stator winding (7), a stator bracket (8), a rotor core (9), a rotor radial ventilation groove (10), a rotor axial ventilation hole (11), a rotor axial air guide ring (12), an extraction type multi-stage fan (13), a press-in type multi-stage fan (14), a rotor shaft (15), a fan plate (16), a rotor winding (17), a gas cooler (18), and a housing (19). The stator core (2) comprises stator core teeth (2-1) and a stator core yoke (2-2); the rotor shaft (15) comprises a rotor main shaft (15-1) and a rotor secondary shaft (15-2); a stator core (2) is provided with a stator The stator has an axial oil channel (4), a stator sealed oil cover (3) wrapped around the outside of the entire stator area, the stator sealed oil cover (3) is filled with flowing cooling oil (20), an oil cooler (1) is installed above the stator bracket (8), an extraction type multi-stage fan (13) and a push-in type multi-stage fan (14) are respectively installed on both sides of the rotor shaft (15), a gas cooler (18) is installed on the air inlet side of the push-in type multi-stage fan (14), a rotor main shaft (15-1) and a rotor secondary shaft (15-2) are connected, a fan plate (16) is evenly installed on the outer surface of the rotor secondary shaft (15-2) along the circumferential direction, a rotor radial ventilation groove (10) and a rotor axial ventilation hole (11) are opened in the rotor core (9), and the rotor axial ventilation hole (11) is connected through a rotor axial air guide ring (12).

2. The ventilation and cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to claim 1, characterized in that: The radius of the stator axial oil channel (4) is 5mm to 15mm; the inner diameter of the stator sealed oil cover (3) is equal to the inner diameter of the stator core (2), and the outer diameter of the stator sealed oil cover (3) is equal to the inner diameter of the oil cooler (1); the cross section of the rotor axial ventilation hole (11) is circular, with a radius of 5mm to 20mm; the inner diameter of the rotor axial air guide ring (12) is equal to the outer diameter of the rotor axial ventilation hole (11); the width of the rotor radial ventilation groove (10) is 5mm to 20mm; a fan plate (16) is installed on the rotor secondary shaft (15-2), and the number of the fan plates (16) is 5 to 8 in the circumferential direction.

3. The ventilation and cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to claim 1, characterized in that: The stator axial oil channel (4) is arranged in a serpentine shape.

4. The ventilation and cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to claim 1, characterized in that: A row of rotor axial ventilation holes (11) is added to the teeth of the rotor core (9).

5. The ventilation and cooling system for a steam turbine generator with a fully oil-cooled stator and a press-in and withdraw-out staggered rotor according to claim 1, characterized in that: The stator axial oil channels (4) are arranged in a staggered manner in the circumferential direction.

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