Method and system for reducing turbine exhaust temperature deviation of a steam feed water pump

Abstract

The application discloses a method and system for reducing steam turbine exhaust temperature deviation of steam-driven feed water pump, belonging to the technical field of steam-driven feed water pump steam turbine, aiming at the high-pressure side exhaust passage and the low-pressure side exhaust passage of the steam-driven feed water pump steam turbine, two mutually independent cylinder exhaust water injection temperature reduction branches are arranged; the water inlet ends of the cylinder exhaust water injection temperature reduction branches are connected to a cylinder exhaust water injection supply water main pipe, and the water outlet ends of the two cylinder exhaust water injection temperature reduction branches are connected to the high-pressure side exhaust passage and the low-pressure side exhaust passage respectively; flow adjusting members are arranged on the cylinder exhaust water injection temperature reduction branches, and the water injection flow of each cylinder exhaust water injection temperature reduction branch is independently adjusted through each flow adjusting member.

Description

Technical Field

[0001] This invention belongs to the technical field of steam turbine for steam-driven feedwater pumps, and specifically relates to a method and system for reducing the exhaust temperature deviation of a steam turbine for steam-driven feedwater pumps. Background Technology

[0002] Steam-driven feedwater pumps are core auxiliary equipment in the feedwater thermal system of thermal power plants, typically driven by a feedwater pump turbine to pressurize and deliver feedwater. The exhaust steam from the feedwater pump turbine is connected to both the high-pressure and low-pressure condensers for condensation. To prevent excessively high exhaust steam temperatures from damaging the expansion joint seals in the exhaust pipes, a desuperheating system is required. This system injects desuperheating water into the exhaust passage to control the exhaust steam temperature within a safe range. Conventional desuperheating systems draw desuperheating water from the power plant's condensate supply mains. When the exhaust steam temperature reaches a set threshold, the spray circuit is activated to cool the steam.

[0003] like Figure 2 In existing technologies, the cylinder spraying system of steam turbines powered by steam-driven feedwater pumps mostly adopts a single-channel water supply main structure, which is connected to the high and low pressure exhaust channels after passing through a set of spraying control valves; some systems only have a spraying circuit in one exhaust channel, with no independent desuperheating branch on the other side. The spraying control valves are mostly on-off solenoid valves, which only have two working states: fully open and fully closed, and the valve opening and closing action is triggered by the exhaust temperature threshold.

[0004] In actual operation, the above-mentioned cylinder spray system has several limitations. First, the high and low pressure exhaust channels share the same spray control circuit, making it impossible to independently allocate the spray volume according to the actual exhaust temperature on both sides. This easily leads to a situation where the exhaust temperature on one side is too high, while the spray volume on the other side is excessive, resulting in a large temperature difference between the two sides. The expansion joint seals of the high-temperature exhaust pipe are constantly under high-temperature conditions, which will accelerate aging and damage. Overspraying on the side will increase condensate consumption and improve the energy consumption of the condensate pump. Second, the on-off control valve cannot achieve continuous and precise adjustment of the spray volume. When the unit's operating conditions fluctuate, the exhaust temperature fluctuates greatly, making it difficult to maintain a stable operating range. Frequent valve on-off switching will also shorten the equipment's service life. Third, the flow capacity of the water supply header has limited design margin. Under high unit load and high ambient temperature conditions, the water supply flow cannot meet the demand for simultaneous cooling of both exhaust sides, easily triggering exhaust temperature over-temperature alarms, or even exceeding the upper limit of safe operating temperature, threatening the stability of equipment operation.

[0005] In summary, the existing cylinder depressurization system has shortcomings in terms of balanced control of exhaust steam temperature on both sides, fine adjustment of water injection volume, and water supply adaptability, making it difficult to ensure stable and balanced operation of the steam turbine with steam-driven feedwater pump under all operating conditions. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing cylinder depressurization systems in terms of balanced control of exhaust steam temperature on both sides, fine adjustment of water injection volume, and water supply adaptability. This invention proposes a method and system for reducing the exhaust steam temperature deviation of the steam-driven feedwater pump turbine.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for reducing the exhaust temperature deviation of a steam turbine driven feedwater pump, comprising the following steps: For the high-pressure side exhaust passage and the low-pressure side exhaust passage of the steam turbine for the steam-driven feedwater pump, two independent exhaust cylinder spray desuperheating branches are set up; Connect the inlet of each cylinder spray desuperheating branch to the cylinder spray water supply main pipe, and connect the outlet of the two cylinder spray desuperheating branches to the high-pressure side exhaust channel and the low-pressure side exhaust channel respectively. Flow regulating components are installed on each cylinder water spray desuperheating branch, and the water spray flow of the cylinder water spray desuperheating branch to which it belongs can be adjusted independently by each flow regulating component.

[0008] Furthermore, the diameter of the main water supply pipe for the cylinder sprayer is increased.

[0009] Furthermore, the inlet ends of the two branch lines of the cylinder spray water cooling system are each connected to the main cylinder spray water supply pipe, and the inlet side pipes of the two branch lines of the cylinder spray water cooling system are laid out independently.

[0010] Furthermore, the flow regulating component is a flow regulating valve.

[0011] Secondly, the present invention provides a system for reducing the exhaust temperature deviation of a steam turbine driven feedwater pump, comprising a main supply pipe for cylinder water spraying, two independent cylinder water spraying desuperheating branches, and two flow regulating components; the inlet ends of the two cylinder water spraying desuperheating branches are connected to the main supply pipe for cylinder water spraying, and the outlet ends of the two cylinder water spraying desuperheating branches are respectively connected to the high-pressure side exhaust passage and the low-pressure side exhaust passage of the steam turbine driven feedwater pump; a flow regulating component is provided on each cylinder water spraying desuperheating branch.

[0012] Furthermore, the main water supply pipe for the cylinder spray is located upstream of the inlet end of the two cylinder spray desuperheating branches, and its diameter is larger than that of the downstream section of the main water supply pipe for the cylinder spray. On each cylinder spray desuperheating branch, a shut-off valve is connected in series on both sides of the flow regulating component, and a bypass shut-off valve is connected in parallel on the flow regulating component. Both the high-pressure side exhaust passage and the low-pressure side exhaust passage are equipped with exhaust temperature detection elements.

[0013] Furthermore, the flow regulating component is a flow regulating valve.

[0014] Thirdly, the present invention provides a steam turbine for a steam-driven feedwater pump, comprising a turbine body, a high-pressure side exhaust passage, a low-pressure side exhaust passage, and a cylinder spray desuperheating assembly; the high-pressure side exhaust passage and the low-pressure side exhaust passage are respectively connected to the exhaust end of the turbine body; the cylinder spray desuperheating assembly includes a cylinder spray water supply header, two independent cylinder spray desuperheating branches, and two flow regulating components; the inlet ends of the two cylinder spray desuperheating branches are connected to the cylinder spray water supply header, and the outlet ends of the two cylinder spray desuperheating branches are respectively connected to the high-pressure side exhaust passage and the low-pressure side exhaust passage; a flow regulating component is provided on each cylinder spray desuperheating branch.

[0015] Furthermore, the main water supply pipe for the cylinder spray is located upstream of the inlet end of the two cylinder spray cooling branch pipes, and its diameter is larger than that of the downstream section of the main water supply pipe for the cylinder spray.

[0016] Furthermore, the flow regulating component is a flow regulating valve.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: This invention proposes a method to reduce the temperature deviation of steam exhaust from a steam-driven feedwater pump turbine. By setting up two independent exhaust cylinder spray cooling branches and configuring independent flow regulation components in each branch, the spray volume can be independently adjusted according to the actual temperature requirements of the high and low pressure exhaust channels, effectively reducing the temperature deviation between the two sides and avoiding the problem of excessively high exhaust temperature on one side and excessive spray volume on the other. The independently adjustable branch structure can accurately match the cooling requirements of the exhaust on one side, reducing ineffective spraying and lowering condensate consumption and condensate pump operating energy consumption. Simultaneously, the independent branch control method avoids mutual interference between the water supply on both sides, improving the stability and adaptability of exhaust temperature control, ensuring the exhaust temperature is stably maintained within a reasonable operating range, reducing heat loss of the exhaust pipe expansion joint sealing components under high-temperature conditions, extending equipment service life, reducing equipment maintenance frequency and costs, and overall improving the operational reliability and economy of the steam-driven feedwater pump turbine exhaust system.

[0018] This invention proposes a system for reducing the temperature deviation of steam turbine exhaust from a steam-driven feedwater pump. By setting up two independent exhaust cylinder spray cooling branches and equipping each branch with an independent flow regulation component, the spray volume can be independently adjusted according to the actual operating conditions of the high and low pressure exhaust channels. This effectively reduces the temperature deviation between the two sides of the exhaust, avoiding the imbalance problem of excessive exhaust temperature on one side and excessive spray volume on the other. The independent branch and independent regulation structure eliminates water supply interference caused by a shared control loop, accurately matching the cooling demand of one side of the exhaust, reducing ineffective spray water consumption, and lowering the operating energy consumption of the condensate system. Simultaneously, the independent branch regulation architecture improves the flexibility and adaptability of exhaust temperature control, ensuring that the exhaust temperatures on both sides are stably maintained within a reasonable range. This alleviates the thermal aging loss of exhaust pipe sealing components, extends equipment service life, and improves the reliability and economy of the exhaust system.

[0019] This invention proposes a steam-driven feedwater pump turbine. By configuring a cylinder spray desuperheating assembly with two independent desuperheating branches on the exhaust side, each branch corresponds to one side of the exhaust channel and is equipped with an independent flow regulating component, independent control of the exhaust temperature on the high and low pressure sides can be achieved. This effectively reduces the temperature deviation between the two sides of the exhaust and avoids problems such as overheating or over-spraying of exhaust on one side. The independent branch control architecture eliminates the mutual influence between the water supply on both sides, and can accurately match the desuperheating requirements of the exhaust on each side, reducing condensate consumption and the operating energy consumption of the supporting pump set. At the same time, the independent adjustment method improves the stability of exhaust temperature control, allowing the exhaust temperature to be stably maintained within the safe operating range, reducing the wear of the expansion joint seals of the exhaust pipeline due to high temperature, reducing the risk of equipment failure and maintenance costs, and improving the overall reliability and operating economy of the steam-driven feedwater pump turbine under all operating conditions. Attached Figure Description

[0020] The accompanying drawings are provided to further understand the invention and constitute a part of this invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0021] Figure 1 This is a schematic diagram of a system structure for reducing the exhaust temperature deviation of a steam turbine in a steam-driven feedwater pump.

[0022] Figure 2 This is a schematic diagram of the cylinder spray water system of a steam turbine with a steam-driven feedwater pump in the prior art.

[0023] Among them, 1-steam turbine body of steam-driven feedwater pump, 21-high pressure side flow regulating valve, 22-high pressure side regulating valve front shut-off valve, 23-high pressure side regulating valve rear shut-off valve, 24-high pressure side bypass shut-off valve, 31-low pressure side flow regulating valve, 32-low pressure side regulating valve front shut-off valve, 33-low pressure side regulating valve rear shut-off valve, 34-low pressure side bypass shut-off valve, 4-high pressure condenser, 5-low pressure condenser, 61-first water supply main pipe inlet shut-off valve, 62-second water supply main pipe inlet shut-off valve, 71-high pressure side spray water branch outlet shut-off valve, 72-low pressure side spray water branch outlet shut-off valve, 81-high pressure side exhaust steam temperature detection element, 82-low pressure side exhaust steam temperature detection element, and A is the exhaust cylinder spray water supply main pipe inlet valve assembly section. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0025] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0027] It should be noted that the terms "first," "second," etc., in the specification and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0028] Example 1 A method for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine specifically includes the following steps: A dual-sided independent desuperheating branch is installed for the high-pressure side exhaust passage and the low-pressure side exhaust passage of the steam-driven feedwater pump turbine. A separate desuperheating branch is installed for each of these two branches, forming a complete spray flow loop. The inlet pipes of the two desuperheating branches are also independently installed, without sharing inlet flow sections, thus avoiding interference between the branches' water supply.

[0029] The upstream inlet pipe section of the main water supply pipe for the cylinder spray water system was enlarged to increase the flow cross-sectional area and improve the overall water supply capacity of the system. The inlets of the two cylinder spray water desuperheating branches were independently connected to the downstream side of the main water supply pipe, and the outlets of the two branches were connected to the high-pressure and low-pressure exhaust channels, respectively. The spray nozzles at the branch outlets were arranged along the exhaust steam flow direction to ensure sufficient contact and mixing between the desuperheating water and the exhaust steam. The inlet of the main water supply pipe for the cylinder spray water system was connected to the power plant's condensate water supply pipe, and the desuperheating water was supplied uniformly by the condensate system.

[0030] Each branch flow regulation unit is configured with a flow regulation component connected in series on the main passage of each branch water spray desuperheating branch, so that each flow regulation component controls the water spray flow area of ​​a single branch. A shut-off valve is connected in series on both the inlet and outlet sides of each flow regulation component, forming a double-sided maintenance isolation structure; simultaneously, a bypass shut-off valve is connected in parallel at both ends of each flow regulation component, forming a branch bypass passage for temporary water supply during valve maintenance.

[0031] To achieve independent flow regulation, a signal association is established between the flow regulation components of each branch and the exhaust temperature detection element of the corresponding exhaust channel. Each flow regulation component independently adjusts the water spray flow of its corresponding exhaust cylinder water spray desuperheating branch. Based on the real-time temperature signal of the corresponding exhaust channel, the flow regulation component adjusts its own flow opening to match the desuperheating requirements of the corresponding exhaust.

[0032] Furthermore, the flow regulating component adopts a flow regulating valve, which can realize continuous linear adjustment of the flow opening, replacing the on / off control mode of the on / off valve, and adapting to the water spray volume requirements under different working conditions.

[0033] Example 2 A system for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine includes a main exhaust water supply pipe, two independent exhaust water desuperheating branches, and two flow regulating components. The inlet ends of the two exhaust water desuperheating branches are connected to the main exhaust water supply pipe, and the outlet ends of the two exhaust water desuperheating branches are respectively connected to the high-pressure side exhaust passage and the low-pressure side exhaust passage of the steam-driven feedwater pump turbine. A flow regulating component is installed on each exhaust water desuperheating branch.

[0034] The main water supply pipe for the cylinder spray is located upstream of the inlet end of the two cylinder spray desuperheating branches. Its diameter is larger than that of the downstream section of the main water supply pipe for the cylinder spray. On each cylinder spray desuperheating branch, a shut-off valve is connected in series on both sides of the flow regulating component, and a bypass shut-off valve is connected in parallel on the flow regulating component. Both the high-pressure side exhaust passage and the low-pressure side exhaust passage are equipped with exhaust temperature detection elements.

[0035] The flow regulating component is a flow regulating valve.

[0036] See Figure 1 The steam turbine body 1 of the steam-driven feedwater pump is equipped with a high-pressure side exhaust end and a low-pressure side exhaust end. The high-pressure side exhaust end is connected to the high-pressure condenser 4 through a high-pressure side exhaust channel, and the low-pressure side exhaust end is connected to the low-pressure condenser 5 through a low-pressure side exhaust channel. A high-pressure side exhaust temperature detection element 81 is installed on the pipeline of the high-pressure side exhaust channel, and a low-pressure side exhaust temperature detection element 82 is installed on the pipeline of the low-pressure side exhaust channel, which are used to collect the real-time temperature parameters of the exhaust steam on the corresponding side.

[0037] The upstream inlet section of the main water supply pipe for the desuperheating spray system is equipped with inlet valve assembly section A, which serves as the main water supply control unit for the entire desuperheating system. Within inlet valve assembly section A, a first water supply main pipe inlet shut-off valve 61 and a second water supply main pipe inlet shut-off valve 62 are connected in series along the water flow direction. These two valves form a two-stage shut-off structure, used to achieve water inlet isolation and maintenance shut-off for the entire spray system. The main pipe section corresponding to inlet valve assembly section A has a larger diameter than the downstream section of the branch main pipe, employing an enlarged diameter design to improve flow capacity and accommodate the flow requirements of simultaneous water supply from both branches.

[0038] Downstream of the main water supply pipe for the cylinder spray water supply, two independent cylinder spray water cooling branches are branched out: the high-pressure side cylinder spray water cooling branch and the low-pressure side cylinder spray water cooling branch. The inlet ends of the two branches are independently connected to the main water supply pipe for the cylinder spray water supply, and the inlet pipes are laid out independently without any shared inlet section.

[0039] The main branch of the high-pressure side cylinder depressurization branch is connected in series along the water flow direction with the high-pressure side regulating valve front shut-off valve 22, the high-pressure side flow regulating valve 21, and the high-pressure side regulating valve rear shut-off valve 23. The inlet of the high-pressure side bypass shut-off valve 24 is connected to the upstream side of the high-pressure side regulating valve front shut-off valve 22, and the outlet is connected to the downstream side of the high-pressure side regulating valve rear shut-off valve 23, forming a parallel bypass path with the high-pressure side flow regulating valve 21.

[0040] A high-pressure side spray water branch outlet shut-off valve 71 is installed at the branch outlet end, and the output end of the high-pressure side spray water branch outlet shut-off valve 71 is connected to the high-pressure side exhaust passage of the steam turbine body 1 of the steam-driven feedwater pump.

[0041] The main branch of the low-pressure side discharge cylinder water spray desuperheating branch is connected in series along the water flow direction with the low-pressure side regulating valve front shut-off valve 32, the low-pressure side flow regulating valve 31, and the low-pressure side regulating valve rear shut-off valve 33; the water inlet of the low-pressure side bypass shut-off valve 34 is connected to the upstream side of the low-pressure side regulating valve front shut-off valve 32, and the water outlet is connected to the downstream side of the low-pressure side regulating valve rear shut-off valve 33, forming a parallel bypass passage with the low-pressure side flow regulating valve 31.

[0042] A low-pressure side spray water branch outlet shut-off valve 72 is installed at the branch outlet end, and the output end of the low-pressure side spray water branch outlet shut-off valve 72 is connected to the low-pressure side exhaust steam passage of the steam-driven feedwater pump turbine body 1.

[0043] The improvements of this embodiment compared to the conventional cylinder spray structure mainly include: setting up two independent cylinder spray cooling branches, corresponding to the high and low pressure exhaust channels respectively; each branch has an independent flow and regulation unit, which can spray water to cool the exhaust on one side; each branch's main passage is equipped with an independent flow regulating valve, replacing the conventional on-off control valve, which can realize continuous regulation of the branch spray flow; the upstream inlet section of the cylinder spray water supply header adopts an enlarged diameter structure to increase the flow cross-sectional area of ​​the header, improve the overall water supply capacity, and meet the flow requirements of the two branches operating simultaneously.

[0044] Example 3 A steam turbine for a steam-driven feedwater pump is equipped with a dual-sided independently adjustable exhaust cylinder water spray desuperheating structure for controlling the exhaust steam temperature during unit operation.

[0045] The steam turbine for the steam-driven feedwater pump includes the turbine body, a high-pressure side exhaust passage, a low-pressure side exhaust passage, and a desuperheating assembly for the exhaust cylinder. The turbine body has a high-pressure side exhaust end and a low-pressure side exhaust end, and the high-pressure side exhaust passage and the low-pressure side exhaust passage are respectively connected to the corresponding exhaust ends of the turbine body; the downstream of the high-pressure side exhaust passage is connected to the high-pressure condenser, and the downstream of the low-pressure side exhaust passage is connected to the low-pressure condenser. The exhaust steam after the turbine body has performed work enters the corresponding condenser through the exhaust passages on both sides to complete condensation and heat exchange.

[0046] Both the high-pressure side exhaust passage and the low-pressure side exhaust passage are equipped with exhaust temperature detection elements to collect the exhaust temperature parameters in the corresponding passages in real time.

[0047] The desuperheating system is located on the exhaust side of the turbine body and includes a main desuperheating water supply pipe, two independent desuperheating water supply branches, and two flow regulating components. The inlet of the main desuperheating water supply pipe is connected to the external condensate supply network, serving as the main input path for the desuperheating water. The inlets of the two desuperheating water supply branches are connected to the downstream side of the main desuperheating water supply pipe, and the outlets of the two desuperheating water supply branches are connected to the high-pressure side exhaust channel and the low-pressure side exhaust channel, respectively. A flow regulating component is installed on the main path of each desuperheating water supply branch, and each individual flow regulating component independently controls the spray flow area of ​​the corresponding branch.

[0048] The main water supply pipe for the cylinder depressurization spray system is located upstream of the inlet of the two branch cylinder depressurization spray systems, and its diameter is larger than that of the downstream section after the branch. This upstream section is the main water supply flow section, and its increased cross-sectional area enhances the overall system's water supply capacity, accommodating the water demand of both branch systems operating simultaneously. Two inlet shut-off valves are connected in series along the water flow direction within this upstream section, forming a main inlet shut-off valve group for isolating the inlet water and shutting off the system for maintenance.

[0049] The two exhaust cylinder water spray desuperheating branches are the high-pressure side exhaust cylinder water spray desuperheating branch and the low-pressure side exhaust cylinder water spray desuperheating branch. The two branches are arranged in a symmetrical structure and each has an independent flow regulation and maintenance bypass structure.

[0050] On the main passage of the high-pressure side cylinder water spray desuperheating branch, a shut-off valve before the regulating valve, a flow regulating component, and a shut-off valve after the regulating valve are connected in series along the water flow direction. The shut-off valves before and after the regulating valve are respectively located on the inlet and outlet sides of the flow regulating component, forming a double-sided isolation structure, which allows for the independent isolation of the flow regulating component for maintenance. A bypass shut-off valve is installed in parallel at both ends of the flow regulating component. The inlet end of the bypass shut-off valve is connected to the upstream pipeline of the flow regulating component, and the outlet end is connected to the downstream pipeline of the flow regulating component, forming a bypass passage for the branch. When the flow regulating component is shut down for maintenance, the basic water flow state of the branch can be maintained through the bypass shut-off valve.

[0051] The outlet end of the high-pressure side exhaust cylinder water spray desuperheating branch is equipped with a branch outlet shut-off valve. The output end of the branch outlet shut-off valve is connected to the high-pressure side exhaust steam channel for on / off control and pipeline isolation on the branch outlet side.

[0052] The structure of the low-pressure side exhaust cylinder water spray desuperheating branch is completely corresponding to that of the high-pressure side exhaust cylinder water spray desuperheating branch. It is also equipped with a shut-off valve before the regulating valve, a flow regulating component, a shut-off valve after the regulating valve, a bypass shut-off valve, and a branch outlet shut-off valve, so as to realize independent flow regulation and maintenance functions.

[0053] During unit operation, the flow regulation components of the two exhaust cylinder water spray desuperheating branches can independently adjust their flow opening according to the temperature detection signal of the corresponding exhaust steam channel, so as to match the desuperheating water supply of the corresponding exhaust steam.

[0054] The flow regulating component is a flow regulating valve, which can realize continuous linear adjustment of the flow opening and adapt to the water spray volume adjustment needs under different working conditions.

[0055] The above content provides a further detailed description of the present invention. It should not be construed that the specific embodiments of the present invention are limited to this. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all such deductions or substitutions should be considered as falling within the protection scope of the present invention as determined by the submitted content.

Claims

1. A method for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine, characterized in that, Includes the following steps: For the high-pressure side exhaust passage and the low-pressure side exhaust passage of the steam-driven feedwater pump turbine, two independent exhaust cylinder spray desuperheating branches are set up; Connect the inlet end of each of the above-mentioned cylinder water spray desuperheating branch to the cylinder water supply main pipe, and connect the outlet end of the two cylinder water spray desuperheating branch to the high-pressure side exhaust channel and the low-pressure side exhaust channel respectively. Each of the aforementioned cylinder water spray desuperheating branches is equipped with a flow regulating component, and the water spray flow of its respective cylinder water spray desuperheating branch can be independently adjusted by each of the aforementioned flow regulating components.

2. The method for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine according to claim 1, characterized in that, Increase the diameter of the main water supply pipe for the exhaust cylinder spray.

3. The method for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine according to claim 1, characterized in that, The inlet ends of the two branch lines of the cylinder water spray cooling are each connected to the main water supply pipe of the cylinder water spray, and the inlet side pipes of the two branch lines of the cylinder water spray cooling are each laid out independently.

4. The method for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine according to claim 1, characterized in that, The flow regulating component is a flow regulating valve.

5. A system for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine, characterized in that, It includes a main water supply pipe for cylinder depressurization spraying, two independent branch pipes for cylinder depressurization spraying, and two flow regulating components; the inlet ends of the two branch pipes for cylinder depressurization spraying are connected to the main water supply pipe for cylinder depressurization spraying, and the outlet ends of the two branch pipes for cylinder depressurization spraying are connected to the high-pressure side exhaust passage and the low-pressure side exhaust passage of the steam turbine of the steam-driven feedwater pump, respectively; each branch pipe for cylinder depressurization spraying is equipped with one flow regulating component.

6. The system for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine according to claim 5, characterized in that, The main water supply pipe for the cylinder spray is located upstream of the inlet end of the two cylinder spray cooling branch pipes, and its diameter is larger than that of the downstream pipe section of the main water supply pipe for the cylinder spray. On each cylinder spray cooling branch pipe, a shut-off valve is connected in series on both sides of the flow regulating component, and a bypass shut-off valve is connected in parallel to the flow regulating component. Both the high-pressure side exhaust channel and the low-pressure side exhaust channel are equipped with exhaust temperature detection elements.

7. The system for reducing the exhaust steam temperature deviation of a steam-driven feedwater pump turbine according to claim 5, characterized in that, The flow regulating component is a flow regulating valve.

8. A steam turbine for a steam-driven feedwater pump, characterized in that, The system includes a steam turbine body, a high-pressure side exhaust passage, a low-pressure side exhaust passage, and a cylinder desuperheating spray system. The high-pressure side exhaust passage and the low-pressure side exhaust passage are respectively connected to the exhaust end of the steam turbine body. The cylinder desuperheating spray system includes a cylinder desuperheating spray water supply main pipe, two independent cylinder desuperheating spray water branches, and two flow regulating components. The inlet ends of the two cylinder desuperheating spray water branches are connected to the cylinder desuperheating spray water supply main pipe, and the outlet ends of the two cylinder desuperheating spray water branches are respectively connected to the high-pressure side exhaust passage and the low-pressure side exhaust passage. Each cylinder desuperheating spray water branch is equipped with one flow regulating component.

9. A steam-driven feedwater pump turbine according to claim 8, characterized in that, The main water supply pipe for the cylinder spray is located upstream of the inlet end of the two cylinder spray cooling branch pipes, and its diameter is larger than that of the downstream section of the main water supply pipe for the cylinder spray.

10. A steam-driven feedwater pump turbine according to claim 8, characterized in that, The flow regulating component is a flow regulating valve.

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