Vane damage prevention exhaust desuperheating water regulation and control system for cylinder cutting unit / deep peak regulation unit

Abstract

The invention provides a steam exhaust desuperheating water regulation and control system for preventing blade damage of a cylinder cutting unit / deep peak regulation unit, and belongs to the technical field of thermal power decoupling and deep peak regulation of thermal power generating units, and the steam exhaust desuperheating water regulation and control system is characterized in that a water supply system is communicated with a condensed water pipeline of the unit, condensed water is used as a water source, and the pressure of desuperheating water is increased by a supercharging device; desuperheating water is sprayed to the tail-stage steam exhaust side of the low-pressure cylinder through the atomization system, atomization particles of the desuperheating water are reduced, the spraying amount of the steam exhaust desuperheating water is reduced, meanwhile, the desuperheating water enters the atomization system in a high-water-pressure state to form high-pressure spray, the spraying coverage area of the desuperheating water can be enlarged, and the steam exhaust desuperheating effect and efficiency of the tail end of the low-pressure cylinder can be improved; the desuperheating water regulation and control system enables atomized desuperheating water to be directly sprayed to the steam exhaust position of the low-pressure cylinder, the using amount of the desuperheating water for steam exhaust at the tail end of the low-pressure cylinder is reduced, liquid drops are reduced, the coverage area is increased, and the situation that a large amount of desuperheating water with poor atomization flows back to the last-stage blade and the penultimate-stage blade of the low-pressure cylinder along with steam exhaust vortexes, and consequently the blades are damaged is avoided.

Description

Technical Field

[0001] The present application belongs to the technical field of thermal power decoupling and deep peak-shaving units in the thermal power industry, and specifically relates to an exhaust steam cooling water control system for a cylinder cutting unit / deep peak-shaving unit to prevent blade damage. Background Art

[0002] With the development of new energy, new energy represented by wind power and solar power generation accounts for an increasing proportion in the power generation side. However, due to the uncontrollable and unstable characteristics of new energy, the quality of power supply and the stability of the power grid have put forward higher requirements for thermal power generation with better regulation performance. Against the background of the increasing demand for deep regulation capabilities of thermal power units, the low-pressure cylinder removal operation and deep peak regulation operation technology of thermal power units came into being, which ensured the quality of power supply and the stability of the power grid of thermal power units, and met the needs of power system transformation.

[0003] However, the operation of the cylinder cutting unit / deep peak regulation unit also brings challenges to the safety of the last and second last stage blades of the steam turbine: after the unit is cut off or operated at low load, the low pressure cylinder exhaust temperature is too high, which has a significant impact on the safety of the steam turbine generator unit. At present, condensate is generally used in the industry to cool the low pressure cylinder exhaust. However, when the unit is running at low load, the condensate particles are large and the cooling effect is poor. Therefore, more condensate needs to be introduced, which causes a large amount of condensate to be discharged into the low pressure cylinder exhaust. At the same time, when the unit is running at low load, the low pressure cylinder exhaust will form a vortex, and a large amount of condensate will flow back to the blades with the vortex, impacting the last and second last stage blades, causing damage or even breakage of the last and second last stage blades, which not only affects the safety of the steam turbine, but also affects the economy of the unit and the overall benefits of the power plant. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] In view of this, according to an embodiment of the present application, a steam exhaust cooling water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit is proposed, comprising:

[0006] A water supply system is arranged outside the unit, the input end of the water supply system is connected to the condensate pipe of the unit, and the condensate pipe provides cooling water to the water supply system;

[0007] The water supply system is provided with a pressure boosting device, which includes a desuperheated water pressure boosting pump to increase the output pressure of the desuperheated water in the water supply system;

[0008] Atomizing system, the atomizing system is connected with the output end of the water supply system, the atomizing system is arranged on the final exhaust side of the low-pressure cylinder of the unit, and the atomizing system sprays cooling water to the final exhaust side of the low-pressure cylinder.

[0009] In a feasible implementation, a condenser is provided at the end of the low-pressure cylinder, and the condenser condenses the steam discharged from the low-pressure cylinder into condensate, and the input end of the condensate pipeline is connected to the hot well of the condenser;

[0010] A condensate pump is provided on the condensate pipeline, and the input end of the water supply system is connected with the output end of the condensate pump.

[0011] In a possible implementation, the water supply system is arranged close to the low-pressure cylinder.

[0012] In a feasible implementation manner, the water supply system includes a cooling water bypass and two cooling water branch pipes, and the two cooling water branch pipes are arranged in parallel on the cooling water bypass.

[0013] In a feasible implementation manner, the booster device is arranged on the desuperheating water branch pipe, the booster device corresponds to the desuperheating water branch pipe one by one, and the booster device includes:

[0014] A desuperheated water booster pump provided on the desuperheated water branch pipe;

[0015] A manual isolation door at the inlet of the desuperheated water booster pump is provided on the desuperheated water branch pipe, and the manual isolation door at the inlet of the desuperheated water booster pump is located at the input end of the desuperheated water branch pipe;

[0016] The electric isolation door at the outlet of the desuperheated water booster pump is arranged on the desuperheated water branch pipe. The electric isolation door at the outlet of the desuperheated water booster pump is located at the output end of the desuperheated water branch pipe. The desuperheated water booster pump is closed and isolated by the electric isolation door at the outlet of the desuperheated water booster pump and the manual isolation door at the inlet of the desuperheated water booster pump;

[0017] A cooling water check valve is arranged on the cooling water branch pipe, the cooling water check valve is located at the output end of the cooling water booster pump, and the cooling water check valve is arranged close to the cooling water booster pump;

[0018] The cooling water regulating gate is arranged on the cooling water branch pipe. The cooling water regulating gate is located between the cooling water check valve and the electric isolation gate at the outlet of the cooling water booster pump. The cooling water regulating gate is used to control the amount of cooling water outputted from the cooling water branch pipe.

[0019] In a feasible implementation manner, a desuperheating water bypass gate is provided on the desuperheating water bypass, and the desuperheating water bypass gate is used to control the connection state between the output end of the condensate pump and the atomization system.

[0020] In a feasible implementation manner, the exhaust steam desuperheating water control system for preventing blade damage of the cylinder cutting unit / deep peak load regulating unit further includes:

[0021] The cooling water pressure remote transmission measuring point is set at the output end of the cooling water supply system. The cooling water pressure remote transmission measuring point is set close to the atomization system to detect the cooling water pressure entering the atomization system.

[0022] In one possible implementation,

[0023] Of the two cooling water branches, one is a working cooling water branch and the other is a standby cooling water branch;

[0024] When the cooling water pressure of the working cooling water branch is lower than 3MPa, the standby cooling water branch is activated.

[0025] In a feasible embodiment, the atomization system includes:

[0026] A water spray pipe, the input end of which is connected to the output end of the water supply system;

[0027] Nozzles, a plurality of nozzles are arranged on the water spray pipe, and the nozzles spray atomized cooling water toward the final exhaust side of the low-pressure cylinder.

[0028] In a possible embodiment, the nozzle comprises a compression inlet liquid end, so as to introduce compressed desuperheated water into the outlet of the nozzle through the compression inlet liquid end.

[0029] Compared with the prior art, the exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak regulation unit in the present application has the following beneficial effects:

[0030] The exhaust steam cooling water control system for preventing blade damage of the cylinder cutting unit / deep peak regulation unit provided in the embodiment of the present application includes a water supply system and an atomization system. The water supply system is connected to the condensate pipe of the unit, and the condensate in the condensate pipe is used as the water source. The pressure of the cooling water is increased by the booster device, and the cooling water is sprayed to the exhaust side of the last stage of the low-pressure cylinder through the atomization system, thereby reducing the atomized particles of the cooling water and reducing the injection amount of the exhaust steam cooling water. At the same time, the cooling water enters the atomization system in a high water pressure state to form a high-pressure spray, which can expand the injection coverage area of ​​the cooling water and better mix with the steam discharged from the low-pressure cylinder, thereby improving the control of the low-pressure cylinder. The exhaust steam cooling effect and efficiency at the end of the low-pressure cylinder; through the setting of the cooling water control system, the atomized cooling water is directly sprayed to the exhaust position of the low-pressure cylinder, so that the atomized cooling water and steam are quickly combined, which improves the exhaust steam cooling effect and efficiency at the end of the low-pressure cylinder, and reduces the amount of cooling water used for the exhaust steam at the end of the low-pressure cylinder, reduces the droplets, and increases the coverage area, avoiding a large amount of poorly atomized exhaust steam cooling water from flowing back to the last and next-last stage blades of the low-pressure cylinder with the exhaust steam vortex, thereby reducing the damage to the last and next-last stage blades of the turbine, avoiding blade breakage accidents, and promoting the safety of thermal power industry and power grid operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0032] Figure 1 A schematic structural diagram of an exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to an embodiment of the present application;

[0033] Figure 2 A schematic structural diagram of a water supply system of an exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit provided in an embodiment of the present application;

[0034] in, Figure 1 and Figure 2 The corresponding relationship between the reference numerals and component names in the figure is:

[0035] 11. Water supply system; 12. Atomization system; 13. Low-pressure cylinder; 14. Condensate pipeline; 16. Condenser; 17. Condensate pump; 18. Booster; 19. Desuperheating water pressure remote transmission measuring point; 20. Desuperheating water bypass door;

[0036] 111. Desuperheating water bypass; 112. Desuperheating water branch pipe;

[0037] 121. water spray pipe; 122. nozzle;

[0038] 181. Cooling water booster pump; 182. Manual isolation door at the inlet of cooling water booster pump; 183. Electric isolation door at the outlet of cooling water booster pump; 184. Cooling water check valve; 185. Cooling water regulating valve. DETAILED DESCRIPTION

[0039] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0041] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application and are not used to limit the present application.

[0043] like Figure 1 As shown, according to an embodiment of the present application, a steam exhaust cooling water control system for preventing blade damage of a cylinder cutting unit / deep peak regulation unit is proposed, comprising: a water supply system 11 and an atomization system 12; the water supply system 11 is arranged outside the unit, and the input end of the water supply system 11 is connected to the condensate water pipe 14 of the unit, and the condensate water pipe 14 provides cooling water to the water supply system 11; a boosting device 18 is provided on the water supply system 11, and the boosting device 18 includes a cooling water boosting pump 181 to increase the output pressure of the cooling water in the water supply system 11; the atomization system 12 is connected to the output end of the water supply system 11, and the atomization system 12 is arranged on the last stage exhaust side of the low-pressure cylinder 13 of the unit, and the atomization system 12 sprays cooling water to the last stage exhaust side of the low-pressure cylinder 13.

[0044] The exhaust steam cooling water control system for preventing blade damage of the cylinder cutting unit / deep peak regulation unit provided in the embodiment of the present application includes a water supply system 11 and an atomization system 12. The water supply system 11 is connected to the condensate pipe 14 of the unit, and the condensate in the condensate pipe 14 is used as the water source. The pressure of the cooling water is increased by the booster 18, and the cooling water is sprayed to the exhaust side of the last stage of the low-pressure cylinder 13 through the atomization system 12, so as to reduce the atomized particles of the cooling water and reduce the injection amount of the exhaust steam cooling water. At the same time, the cooling water enters the atomization system 12 in a high water pressure state to form a high-pressure spray, which can expand the spray coverage area of ​​the cooling water and better mix with the steam discharged from the low-pressure cylinder 13. It can improve the cooling effect and efficiency of the exhaust steam at the end of the low-pressure cylinder 13; through the setting of the cooling water control system, the atomized cooling water is directly sprayed to the exhaust position of the low-pressure cylinder 13, and then the atomized cooling water and steam are quickly combined, thereby improving the cooling effect and efficiency of the exhaust steam at the end of the low-pressure cylinder 13, and reducing the amount of cooling water used in the exhaust steam at the end of the low-pressure cylinder 13, reducing the size of droplets, and increasing the coverage area, thereby avoiding a large amount of poorly atomized exhaust steam cooling water from flowing back to the last and next-last blades of the low-pressure cylinder 13 with the vortex, thereby reducing damage to the last and next-last blades of the turbine, avoiding blade breakage accidents, and promoting the safety of thermal power industry and power grid operation.

[0045] It should be noted that the cooling water is a part of the liquid in the condensate produced by the exhaust steam of the low-pressure cylinder 13. The cooling water is atomized to reduce the amount of cooling water used, thereby achieving effective use of the condensate.

[0046] like Figure 1 As shown, in a feasible embodiment, a condenser 16 is provided at the end of the low-pressure cylinder 13, and the condenser 16 condenses the steam discharged from the low-pressure cylinder 13 into condensate, and the input end of the condensate pipe 14 is connected to the hot well of the condenser 16; a condensate pump 17 is provided on the condensate pipe 14, and the input end of the water supply system 11 is connected to the output end of the condensate pump 17.

[0047] In this technical solution, after the steam enters the low-pressure cylinder 13 to do work, it is discharged from the last stage of the low-pressure cylinder 13 to the condenser 16. The condenser 16 condenses the steam discharged from the low-pressure cylinder 13 into condensate. The condensate enters the condensate pump 17 through the condensate pipe 14. The condensate is pressurized by the condensate pump 17 and transported to the low-pressure heater and deaerator to increase the temperature of the condensate and improve the thermal efficiency of the unit, while reducing the oxygen content of the condensate to avoid corrosion of equipment.

[0048] like Figure 1 As shown, in a possible implementation, the water supply system 11 is arranged close to the low-pressure cylinder 13 .

[0049] In this technical solution, the water supply system 11 is installed outside the steam turbine near the low-pressure cylinder 13 to shorten the pipeline layout length of the cooling water control system and the fluid resistance along the way, which is beneficial to reducing the power consumption of the cooling water control system and saving usage costs.

[0050] In a feasible implementation manner, there is one desuperheating water bypass 111 and two desuperheating water branch pipes 112 , and the two desuperheating water branch pipes 112 are arranged in parallel on the desuperheating water bypass 111 .

[0051] In this technical solution, the cooling water bypass 111 and the two cooling water branch pipes 112 are connected in parallel, and the boosting device 18 is arranged on the cooling water branch pipe 112. The cooling water branch pipe 112 boosts the cooling water through the cooling water boosting pump 181 to improve the atomization effect of the atomization system 12. The cooling water bypass 111 and the cooling water branch pipe 112 are connected in parallel to ensure that when the two cooling water branch pipes 112 fail, the cooling water can enter the atomization system 12 through the cooling water bypass 111, without affecting the cooling of the exhaust steam of the low-pressure cylinder 13, thereby ensuring the stable operation of the unit.

[0052] It can be understood that there can be multiple cooling water branch pipes 112, one cooling water branch pipe 112 is working, and the remaining cooling water branch pipes 112 are used as backup pipes for cooling water pressurization to ensure reliable and stable operation of the unit.

[0053] like Figure 2 As shown, in a feasible implementation manner, the boosting device 18 is arranged on the cooling water branch pipe 112, and the boosting device 18 corresponds to the cooling water branch pipe 112 one by one. The boosting device 18 includes: a cooling water boosting pump 181 arranged on the cooling water branch pipe 112; a manual isolation door at the inlet of the cooling water boosting pump 181, an electric isolation door at the outlet of the cooling water boosting pump 181, a cooling water check valve 184 and a cooling water regulating valve 185; a manual isolation door at the inlet of the cooling water boosting pump 181 is arranged on the cooling water branch pipe 112, and the manual isolation door at the inlet of the cooling water boosting pump 181 is located at the input end of the cooling water branch pipe 112; an electric isolation door at the outlet of the cooling water boosting pump 181 is arranged on the cooling water branch pipe 112, and the cooling water check valve 184 and the cooling water regulating valve 185 are arranged on the cooling water branch pipe 112. The electric isolation door at the outlet of the cooling water branch pipe 112 is located at the output end of the cooling water booster pump 181, and the cooling water booster pump 181 is closed and isolated by the electric isolation door at the outlet of the cooling water booster pump 181 and the manual isolation door at the inlet of the cooling water booster pump 181; the cooling water check valve 184 is arranged on the cooling water branch pipe 112, and the cooling water check valve 184 is located at the output end of the cooling water booster pump 181, and the cooling water check valve 184 is arranged close to the cooling water booster pump 181; the cooling water regulating valve 185 is arranged on the cooling water branch pipe 112, and the cooling water regulating valve 185 is located between the cooling water check valve 184 and the electric isolation door at the outlet of the cooling water booster pump 181, and the cooling water regulating valve 185 is used to control the amount of cooling water outputted from the cooling water branch pipe 112.

[0054] In this technical solution, the cooling water booster pump 181 is arranged on the cooling water branch pipe 112. The cooling water booster pump 181 is used to boost the cooling water transported by the cooling water branch pipe 112; the manual isolation door at the inlet of the cooling water booster pump 181 is located at the input end of the cooling water branch pipe 112, and the electric isolation door at the outlet of the cooling water booster pump 181 is arranged on the cooling water branch pipe 112. When a cooling water branch pipe 112 needs to be repaired, the electric isolation door at the outlet of the cooling water booster pump 181 and the manual isolation door at the inlet of the cooling water booster pump 181 will The corresponding cooling water branch pipe 112 is isolated from other pipelines, so as to realize the isolation and maintenance requirements of the cooling water branch pipe 112; a cooling water check valve 184 is provided on the cooling water branch pipe 112 near the output end of the cooling water booster pump 181 to ensure that the cooling water does not flow back after the cooling water booster pump 181 is shut down, so as to avoid affecting the normal operation of the unit; a cooling water regulating gate 185 is provided on the cooling water branch pipe 112 to adjust the cooling water supply and exhaust volume in real time through the cooling water regulating gate 185 to ensure the appropriate amount of cooling water.

[0055] Furthermore, the cooling water booster pump 181 is connected to the frequency-modulated motor, and the cooling water booster pump 181 is driven by the frequency-modulated motor to accurately control the rotation speed of the cooling water booster pump 181, thereby optimizing the cooling water pressure at the output end of the cooling water booster pump 181, which is beneficial to ensuring the stability of the water pressure after the cooling water is pressurized.

[0056] Furthermore, a manual isolation door is provided at the inlet of the cooling water booster pump 181, and an electric isolation door is provided at the outlet of the cooling water booster pump 181 to ensure that after a system failure, the manual isolation door at the inlet of the cooling water booster pump 181 and the electric isolation door at the outlet of the cooling water booster pump 181 can be quickly and reliably closed to isolate the cooling water branch pipe 112.

[0057] Furthermore, when the cooling water branch pipe 112 is working, the opening of the cooling water regulating door 185 controls the exhaust temperature of the low-pressure cylinder 13 to be within a given range, and the frequency modulation motor controls the pressure of the cooling water to be within the range of 4 to 5 MPa.

[0058] like Figure 1 and Figure 2 As shown, in a feasible implementation manner, a desuperheating water bypass 111 door 20 is provided on the bypass pipe, and the desuperheating water bypass 111 door 20 is used to control the connection state between the output end of the condensate pump 17 and the atomization system 12 .

[0059] In this technical solution, the connection status between the output end of the condensate pump 17 and the atomization system 12 is controlled by the cooling water bypass 111 door 20. When the cooling water branch pipe 112 fails, the cooling water bypass 111 door 20 can be opened to connect the output end of the condensate pump 17 with the atomization system 12, and the exhaust steam of the low-pressure cylinder 13 can be continued to be cooled, so that the unit can operate smoothly.

[0060] In this technical solution, if any device among the cooling water regulating gate 185, the cooling water check valve 184 and the cooling water booster pump 181 of the two cooling water branch pipes 112 fails, resulting in the two cooling water branch pipes 112 being unable to operate normally, the cooling water bypass 111 can be used for short-term operation to directly supply water to the atomization system 12 to ensure continuous and uninterrupted cooling water spray.

[0061] like Figure 1 and Figure 2 As shown, in a feasible implementation manner, the exhaust steam cooling water control system for preventing blade damage of the cylinder cutting unit / deep peak regulation unit also includes: a cooling water pressure remote transmission measuring point 19, which is arranged at the output end of the water supply system 11, and the cooling water pressure remote transmission measuring point 19 is arranged close to the atomization system 12 to detect the cooling water pressure entering the atomization system 12.

[0062] In this technical solution, a cooling water pressure remote transmission measuring point 19 is arranged on the cooling water outlet main pipe section near the atomizing system 12 to detect the water pressure of the cooling water entering the atomizing system 12, thereby facilitating the adjustment of the cooling water booster pump 181 and the atomizing system 12 according to the cooling water pressure, so that the spray volume of the cooling water matches the exhaust volume of the low-pressure cylinder 13, ensuring effective cooling of the end of the low-pressure cylinder 13, while avoiding the waste of cooling water and improving the utilization efficiency of the cooling water.

[0063] The cooling water outlet main pipe section is located at the output end of the water supply system 11 .

[0064] Furthermore, the cooling water control system is electrically connected to the control system of the unit, and the cooling water pressure remote transmission measuring point 19 is connected to the control system. The control system receives the cooling water pressure remote transmission measuring point 19 signal to facilitate the adjustment of the water supply system 11 and the atomization system 12.

[0065] In a feasible implementation, of the two cooling water branch pipes 112, one is a main cooling water branch pipe 112, and the other is a backup cooling water branch pipe 112; when the cooling water pressure of the main cooling water branch pipe 112 is lower than 3MPa, the backup cooling water branch pipe 112 is activated.

[0066] In this technical solution, the two cooling water branch pipes 112 serve as backup for each other. When one cooling water branch pipe 112 fails, the other cooling water branch pipe 112 can be put into use immediately to ensure the continuity of the cooling water pressurization work, thereby ensuring the continuity of the cooling of the exhaust steam at the end of the low-pressure cylinder 13.

[0067] In this technical solution, the cooling water booster pumps 181 and the outlet electric isolation doors of the two cooling water branch pipes 112 are controlled by logical protection; when the cooling water booster pump 181 of the main cooling water branch pipe 112 trips, the cooling water booster pump 181 of the standby cooling water branch pipe 112 is started; when the cooling water pressure remote transmission measuring point 19 detects that the cooling water pressure is lower than 3MPa, the standby cooling water branch pipe 112 is activated to avoid the failure of the main cooling water booster pump 181, which causes the cooling water pressure to decrease so that it cannot meet the exhaust steam cooling demand.

[0068] Furthermore, when the exhaust temperature at the end of the low-pressure cylinder 13 is higher than the set protection value, the standby cooling water booster pump 181 is started, and the main cooling water booster pump 181 and the standby cooling water booster pump 181 work at the same time to avoid the situation where the exhaust temperature is too high due to the single cooling water booster pump 181 failing to meet the exhaust temperature reduction requirements under special working conditions. When the condensate pressure in the condensate pipe 14 is less than 0.2MPa, the two cooling water booster pumps 181 stop running, and it is determined that the unit is out of operation and does not need exhaust cooling water, and the two cooling water booster pumps 181 do not run.

[0069] like Figure 1 As shown, in a feasible embodiment, the atomization system 12 includes: a water spray pipe 121 and a nozzle 122; the input end of the water spray pipe 121 is connected to the output end of the water supply system 11; a plurality of nozzles 122 are arranged on the water spray pipe 121, and the nozzles 122 spray atomized cooling water toward the final exhaust side of the low-pressure cylinder 13.

[0070] In this technical solution, the cooling water pressurized by the water supply system 11 enters each nozzle 122 through the water spray pipe 121, and the nozzle 122 atomizes and sprays the high-pressure cooling water to reduce the amount of cooling water used in the exhaust steam of the low-pressure cylinder 13. At the same time, the particles of the cooling water are smaller after atomization. Even if the atomized cooling water flows back to the blades with the vortex formed by the exhaust steam of the low-pressure cylinder 13, the impact on the last-stage and next-last-stage blades is very small, which can reduce the damage to the last-stage and next-last-stage blades.

[0071] In a possible implementation, the nozzle 122 includes a compression inlet liquid end, so as to introduce compressed desuperheated water into the nozzle 122 outlet through the compression inlet liquid end.

[0072] In this technical solution, compressed cooling water is introduced into the outlet of the nozzle 122 through the compressed inlet liquid end to interact inside the nozzle 122 to produce a uniform spray with small droplet size. The mutual collision and friction between the gas and liquid phases are utilized to improve the atomization effect of the cooling water, thereby preventing a large amount of poorly atomized cooling water from entering the blades and impacting the last-stage and next-last-stage blades, thereby reducing the damage to the last-stage and next-last-stage blades caused by the low atomization degree of the cooling water.

[0073] Furthermore, the nozzle 122 adopts an umbrella-shaped atomizing adjustable nozzle to adjust the atomization effect of the cooling water according to the exhaust steam volume of the low-pressure cylinder 13.

[0074] Furthermore, the nozzle 122 adopts a double-headed double-eccentric nozzle, and the cooling water flow rate of the atomizing injection cavity of the double-headed double-eccentric nozzle is half of that of the standard nozzle, so that a smaller droplet size can be obtained, thereby improving the atomization effect of the cooling water.

[0075] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0076] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A steam exhaust cooling water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit, characterized in that: The exhaust steam desuperheating water control system for preventing blade damage of the cylinder cutting unit / deep peak regulation unit includes: A water supply system, wherein the water supply system is arranged outside the unit, an input end of the water supply system is connected to a condensate water pipeline of the unit, and the condensate water pipeline provides cooling water to the water supply system; The water supply system is provided with a pressure boosting device, and the pressure boosting device comprises a desuperheated water pressure boosting pump to increase the output pressure of the desuperheated water in the water supply system; An atomizing system is connected to the output end of the water supply system, and the atomizing system is arranged on the final exhaust side of the low-pressure cylinder of the unit, and the atomizing system sprays cooling water to the final exhaust side of the low-pressure cylinder.

2. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 1 is characterized in that: A condenser is provided at the end of the low-pressure cylinder, and the condenser condenses the steam discharged from the low-pressure cylinder into condensed water, and the input end of the condensed water pipeline is connected to the hot well of the condenser; The condensate water pipeline is provided with a condensate water pump, and the input end of the water supply system is communicated with the output end of the condensate water pump.

3. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 1 is characterized in that: The water supply system is arranged close to the low-pressure cylinder.

4. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 1 is characterized in that: The water supply system comprises a cooling water bypass and two cooling water branch pipes, and the two cooling water branch pipes and the cooling water bypass are arranged in parallel on the cooling water bypass.

5. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 4 is characterized in that: The booster device is arranged on the desuperheating water branch pipe, and the booster device corresponds to the desuperheating water branch pipe one by one. The booster device comprises: The desuperheating water booster pump provided on the desuperheating water branch pipe; A manual isolation door at the inlet of the desuperheated water booster pump, the manual isolation door at the inlet of the desuperheated water booster pump is arranged on the desuperheated water branch pipe, and the manual isolation door at the inlet of the desuperheated water booster pump is located at the input end of the desuperheated water branch pipe; The electric isolation door at the outlet of the desuperheated water booster pump is arranged on the desuperheated water branch pipe. The electric isolation door at the outlet of the desuperheated water booster pump is located at the output end of the desuperheated water branch pipe. The desuperheated water booster pump is closed and isolated by the electric isolation door at the outlet of the desuperheated water booster pump and the manual isolation door at the inlet of the desuperheated water booster pump; A superheated water check valve, the superheated water check valve is arranged on the superheated water branch pipe, the superheated water check valve is located at the output end of the superheated water booster pump, and the superheated water check valve is arranged close to the superheated water booster pump; The cooling water regulating gate is arranged on the cooling water branch pipe, and the cooling water regulating gate is located between the cooling water check valve and the cooling water booster pump outlet electric isolation gate. The cooling water regulating gate is used to control the amount of cooling water output by the cooling water branch pipe.

6. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 4 is characterized in that: The desuperheating water bypass is provided with a desuperheating water bypass door, and the desuperheating water bypass door is used to control the connection state between the output end of the condensate pump and the atomization system.

7. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 4, characterized in that: The exhaust steam desuperheating water control system for preventing blade damage of the cylinder cutting unit / deep peak regulation unit also includes: A remote transmission measuring point for the pressure of cooling water is provided at the output end of the water supply system. The remote transmission measuring point for the pressure of cooling water is provided close to the atomization system to detect the pressure of cooling water entering the atomization system.

8. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 4, characterized in that: Of the two cooling water branches, one is a working cooling water branch and the other is a standby cooling water branch; When the cooling water pressure of the working cooling water branch pipe is lower than 3MPa, the standby cooling water branch pipe is activated.

9. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 1, characterized in that: The atomization system comprises: A water spray pipe, the input end of which is connected to the output end of the water supply system; Nozzles, a plurality of nozzles are arranged on the water spray pipe, and the nozzles spray atomized cooling water toward the final exhaust side of the low-pressure cylinder.

10. The exhaust steam desuperheating water control system for preventing blade damage of a cylinder cutting unit / deep peak load regulating unit according to claim 9, characterized in that: The nozzle includes a compression inlet liquid end to introduce compressed desuperheated water into an outlet of the nozzle through the compression inlet liquid end.

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