Thermal power plant air-wet-cooling series unit device and control optimization operation method thereof
By using the surplus of the cooling water tower and automatic detection and control system in the air-wet and cold series unit of the thermal power plant, the air-cooled unit is exhausted, which solves the problems of high back pressure and high coal consumption in summer, and achieves the effect of reducing back pressure and coal consumption and improving operational economics.
Patent Information
- Application Number
- CN202411789802.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2025-03-14
AI Technical Summary
In summer, the unit's operating back pressure is high, resulting in increased coal consumption and poor operating economy.
By introducing the surplus of the water supply pump turbine cooling water tower into the air-wet-cooled series unit device of the thermal power plant, the first condenser is used to cool the exhaust steam of part of the air-cooled unit, reducing the back pressure of the unit, and equipped with an automatic detection and control system to monitor and adjust the exhaust steam in real time.
It effectively reduces the unit's back pressure and coal consumption, improves operating economy, and reduces the plant's electricity consumption by saving air-cooling fans.
Smart Images
Figure CN119616607A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of thermal power generation, relates to an air-wet cooling series unit device of a thermal power plant, and also relates to an air-wet cooling series control optimization operation method of the thermal power plant. Background Art
[0002] Long-term operation of the air-cooled condenser will cause the equipment to be unable to guarantee the original design value. In addition, the ambient temperature increases year by year. During the summer period when electricity demand is higher, the ambient temperature is often far higher than the design temperature. Under the influence of ambient temperature and strong wind, the back pressure of the air-cooled unit will suddenly rise, posing a safety hazard. On the other hand, when the back pressure increases, the volume flow of the last-stage blades of the low-pressure cylinder will become smaller, causing the axial flow to be concentrated on the top of the blades, making the working condition of the last-stage blades complicated and reducing safety.
[0003] Due to the degradation of long-term operation, the air-cooled condenser is difficult to reach the design back pressure value at the design temperature. On the one hand, under the condition of limited fine treatment, too high back pressure will lead to over-temperature of fine treatment. In order to ensure the safe operation of the unit, it is necessary to artificially reduce the unit load, thereby reducing the unit back pressure, resulting in reduced power generation, and serious grid assessment, and greatly reduced unit economy. On the other hand, under the condition of high temperature in summer, when the back pressure is high, if the same amount of electricity is generated, the furnace side load needs to be increased. Due to the problem of furnace side flue resistance, the unit power generation will be limited. Therefore, the unit has a high operating back pressure in summer, the unit coal consumption increases, and the operating economy is poor. An optimized operation method is urgently needed to improve the unit's economy. Summary of the invention
[0004] The purpose of the present invention is to provide an air-wet cooling series unit device for a thermal power plant, which solves the problems of high back pressure during summer operation of the existing units, increased coal consumption of the units, and poor operating economy.
[0005] The second object of the present invention is to provide the above-mentioned thermal power plant air-wet cooling series control optimization operation method.
[0006] The first technical scheme adopted by the present invention is that the air-wet cooling series unit device of a thermal power plant includes an air-cooling unit and a detection control system, the air-cooling unit includes a steam turbine, the output end of the steam turbine is respectively connected to the air-cooling island and the first condenser through pipelines, an electric regulating valve of the steam turbine exhaust steam branch pipe is arranged between the steam turbine and the first condenser, and the output end of the air-cooling island is connected to the exhaust device through a pipeline; it also includes a feedwater pump steam turbine cooling water tower, the output end of the feedwater pump steam turbine cooling water tower is connected to the second condenser through a pipeline, the output end of the second condenser is connected to the first condenser through a pipeline, and the output end of the first condenser is respectively connected to the exhaust device and the feedwater pump steam turbine cooling water tower through pipelines; The detection control system is connected to the air cooling unit via a signal line.
[0007] The present invention is also characterized in that: A circulating water pump and a first valve are sequentially arranged on the pipeline between the cooling water tower of the feedwater pump turbine and the second condenser in the flow direction, and a third valve is arranged on the pipeline between the second condenser and the first condenser; It also includes a second valve and a fourth valve, one end of the second valve is connected to the pipeline between the first condenser and the third valve, the other end of the second valve is connected to the pipeline between the circulating water pump and the first valve, one end of the fourth valve is connected to the pipeline between the first condenser and the third valve, the other end of the fourth valve is connected to the pipeline between the first condenser and the feed water pump turbine cooling water tower, and a second condenser circulating water flow meter is provided on the pipeline between the turbine exhaust steam branch pipe electric regulating valve and the first condenser.
[0008] The detection and control system comprises a condensed water temperature measuring meter after cooling of the air-cooled exhaust steam branch pipe, a water temperature measuring meter for the outlet of the cooling water tower, a water temperature measuring meter for the inlet of the cooling water tower and a condensed water temperature measuring meter for the air-cooled island. The condensed water temperature measuring meter after cooling of the air-cooled exhaust steam branch pipe is arranged on the pipeline between the first condenser and the exhaust device, the condensed water temperature measuring meter for the air-cooled island is arranged on the pipeline between the air-cooled island and the exhaust device, the water temperature measuring meter for the outlet of the cooling water tower is arranged on the pipeline between the circulating water pump and the first valve, the water temperature measuring meter for the inlet of the cooling water tower is arranged on the pipeline between the first condenser and the cooling water tower of the feed water pump turbine, and the condensed water temperature measuring meter after cooling of the air-cooled exhaust steam branch pipe, the water temperature measuring meter for the outlet of the cooling water tower, the water temperature measuring meter for the inlet of the cooling water tower and the condensed water temperature measuring meter for the air-cooled island are all connected to the electric regulating valve of the exhaust steam branch pipe of the steam turbine through a signal line; It also includes a first condenser circulating water flow meter, which is located between the first valve and the second condenser and is connected to the turbine exhaust steam branch pipe electric regulating valve through a signal line.
[0009] The second technical solution adopted by the present invention is a method for controlling and optimizing the operation of air-wet cooling series units in a thermal power plant, and the specific method is as follows: Step 1: Collect relevant data through the detection and control system; Step 2: Determine whether the cooling water tower of the feedwater pump turbine has cooling margin based on the collected data. If there is no cooling margin, the control system closes the electric regulating valve of the turbine exhaust steam branch pipe; if there is cooling margin, calculate the exhaust steam value that can be cooled by the margin; Step 3: Control the opening of the electric regulating valve of the exhaust steam branch pipe of the steam turbine and gradually control the system to remain stable.
[0010] The present invention is also characterized in that: The data collected in step 1 include: the actual circulating water volume Q1 required by the feedwater pump turbine, the water temperature T1 entering the cooling tower of the feedwater pump turbine, the water temperature T2 leaving the cooling tower of the feedwater pump turbine, the condensate temperature T3 of the air cooling island, and the condensate temperature T4 of the exhaust steam branch pipe.
[0011] The actual circulating water volume Q1 required by the feed water pump steam turbine is detected by the circulating water flow meter of the first condenser. The inlet water temperature T1 of the cooling water tower of the feed water pump steam turbine is detected by the inlet water temperature meter of the cooling water tower. The outlet water temperature T2 of the cooling water tower of the feed water pump steam turbine is detected by the outlet water temperature meter of the cooling water tower. The condensate temperature T3 of the air-cooled island is detected by the condensate temperature meter of the air-cooled island, and the condensate temperature T4 of the exhaust steam branch pipe is detected by the condensate temperature meter after the cooling of the exhaust steam branch pipe of the air-cooled island.
[0012] The specific method of step 2 is as follows: By comparing Q1 with the rated cooling circulating water volume Q of the feed water pump steam turbine, it is judged whether there is a cooling margin for the cooling water tower of the feed water pump steam turbine. If Q1 = Q, there is no cooling margin, and the control system closes the electric valve of the exhaust steam branch; if Q1 < Q, there is a cooling margin Q0 = Q - Q1 for the cooling water tower of the feed water pump steam turbine, and then the amount of exhaust steam Q2 that can be cooled by the cooling margin of the cooling water tower of the feed water pump steam turbine is calculated according to the following formula:
[0013] In the formula, C is the specific heat capacity of the circulating water, H 1 is the exhaust enthalpy of the air-cooled exhaust device, T 3 is the condensate temperature of the air-cooled island, P 1 is the vacuum value of the air-cooled exhaust device, is the enthalpy value of the condensate after cooling of the exhaust device.
[0014] The specific method of step 3 is as follows: gradually increase the opening of the electric valve of the exhaust steam branch, and at the same time compare the condensate temperature T 4 of the exhaust steam branch pipe with the condensate temperature T 3 of the air-cooled island. When T 4 = T 3, the opening of the electric valve of the exhaust steam branch remains unchanged, and the system remains stable.
[0015] The beneficial effects of the present invention are: (1) The air-wet cooling series unit device of a thermal power plant of the present invention utilizes the surplus of the cooling water tower of the feedwater pump turbine equipped with the air-cooling unit to cool part of the exhaust steam of the air-cooling unit through the first condenser, thereby reducing the back pressure of the unit and reducing the coal consumption of the unit; at the same time, a set of automatic detection and control system is added to detect the circulating water flow rate, the water temperature of the circulating water entering the tower, the water temperature of the circulating water leaving the tower, and the condensate temperature after cooling of the air-cooled exhaust steam branch pipe at the feedwater pump turbine condenser. Through the detection and control system, the measured data can be used to determine the surplus value of the cooling water tower of the feedwater pump turbine, and then the exhaust steam amount that can be cooled by the exhaust steam of the turbine in the first condenser is calculated, and then the exhaust steam of the turbine entering the first condenser is controlled by the exhaust steam pipeline valve. In spring, autumn and winter, this set of equipment can be used to save the power consumption of the air-cooling fan, reduce the power consumption rate of the plant, and improve the economic efficiency of the unit operation; (2) The air-wet cooling series unit device of the thermal power plant of the present invention utilizes the existing small unit cooling water tower to cool part of the steam turbine exhaust steam, effectively reducing the back pressure of the air-cooled unit, thereby improving the safety of the unit and reducing the energy consumption of the unit. It has great energy-saving potential and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic diagram of an air-wet cooling series unit device of a thermal power plant according to the present invention; Figure 2 It is the flow chart of the detection and control system of the air-wet cooling series unit in a thermal power plant.
[0017] In the figure, 1. steam turbine, 2. air-cooling island, 3. exhaust device, 4. first condenser, 5. second condenser, 6. feed water pump turbine cooling water tower, 7. circulating water pump, 8. first valve, 9. second valve, 10. third valve, 11. fourth valve, 12. first condenser circulating water flow meter, 13. steam turbine exhaust steam branch pipe electric regulating valve, 14. air-cooled exhaust steam branch pipe cooling condensate temperature meter, 15. cooling water tower outlet water temperature meter, 16. cooling water tower inlet water temperature meter, 17. second condenser circulating water flow meter, 18. air-cooling island condensate temperature meter. DETAILED DESCRIPTION
[0018] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.
[0019] The present invention provides a thermal power plant air-wet cooling series unit device, which utilizes the excess capacity of the cooling tower to add a condenser to cool a certain amount of exhaust steam, thereby reducing the back pressure of the air-cooling unit. Figure 1As shown, it includes an air-cooling unit and a detection control system, the air-cooling unit includes a steam turbine, the output end of the steam turbine is respectively connected to the air-cooling island 2 and the first condenser 4 through pipelines, an electric regulating valve 13 of the steam turbine exhaust steam branch pipe is arranged between the steam turbine and the first condenser 4, and the output end of the air-cooling island 2 is connected to the exhaust device 3 through a pipeline; it also includes a feedwater pump steam turbine cooling water tower 6, the output end of the feedwater pump steam turbine cooling water tower 6 is connected to the second condenser 5 through a pipeline, the output end of the second condenser 5 is connected to the first condenser 4 through a pipeline, and the output end of the first condenser 4 is respectively connected to the exhaust device 3 and the feedwater pump steam turbine cooling water tower 6 through pipelines; Furthermore, a circulating water pump 7 and a first valve 8 are sequentially provided on the pipeline between the feedwater pump turbine cooling water tower 6 and the second condenser 5 in the flow direction, and a third valve 10 is provided on the pipeline between the second condenser 5 and the first condenser 4; It also includes a second valve 9 and a fourth valve 11. One end of the second valve 9 is connected to the pipeline between the first condenser 4 and the third valve 10, and the other end of the second valve 9 is connected to the pipeline between the circulating water pump 7 and the first valve 8. One end of the fourth valve 11 is connected to the pipeline between the first condenser 4 and the third valve 10, and the other end of the fourth valve 11 is connected to the pipeline between the first condenser 4 and the feed water pump turbine cooling water tower 6. A second condenser circulating water flow meter 17 is provided on the pipeline between the turbine exhaust steam branch pipe electric regulating valve 13 and the first condenser 4.
[0020] The detection control system is connected to the air-cooling unit through a signal line. Specifically, the detection control system includes a condensate temperature measuring meter 14 for the air-cooled exhaust steam branch pipe after cooling, a water temperature measuring meter 15 for the cooling water tower outlet, a water temperature measuring meter 16 for the cooling water tower inlet, and a condensate temperature measuring meter 18 for the air-cooled island. The condensate temperature measuring meter 14 for the air-cooled exhaust steam branch pipe after cooling is arranged on the pipeline between the first condenser 4 and the exhaust device 3, and the condensate temperature measuring meter 18 for the air-cooled island is arranged between the air-cooled island 2 and the exhaust device 3. On the pipeline, the cooling water tower outlet water temperature measuring meter 15 is arranged on the pipeline between the circulating water pump 7 and the first valve 8, the cooling water tower inlet water temperature measuring meter 16 is arranged on the pipeline between the first condenser 4 and the feed water pump turbine cooling water tower 6, the condensed water temperature measuring meter 14 after cooling of the air-cooled exhaust steam branch pipe, the cooling water tower outlet water temperature measuring meter 15, the cooling water tower inlet water temperature measuring meter 16 and the air-cooled island condensed water temperature measuring meter 18 are all connected to the turbine exhaust steam branch pipe electric regulating valve 13 through a signal line; It also includes a first condenser circulating water flow meter 12, which is located between the first valve 8 and the second condenser 5. The first condenser circulating water flow meter 12 is connected to the turbine exhaust steam branch pipe electric regulating valve 13 through a signal line.
[0021] A part of the exhaust steam of the steam turbine 1 is cooled by the air-cooled island 2 and then flows into the exhaust device 3; another part is cooled by the first condenser 4 and then flows into the exhaust device 3. The circulating water of the original condensate pump steam turbine condenser is pumped out from the condensate pump steam turbine cooling water tower 6 by the circulating water pump 7, first passes through the second condenser 5, then passes through the first condenser 4, and finally flows into the condensate pump steam turbine cooling water tower 6.
[0022] The control optimization operation method for the air-cooled and wet-cooled series units in thermal power plants controls the opening of the electric valve of the exhaust steam branch according to the circulating water of the small steam turbine and the condensate temperature after the cooling of the air-cooled exhaust steam branch pipe, and then controls the flow rate of the exhaust steam branch. As Figure 2 shown, the specific method is as follows: Step 1: Collect relevant data through the detection control system; The collected data includes: the actual required circulating water volume Q1 of the condensate pump steam turbine, the water temperature T1 entering the cooling water tower 6 of the condensate pump steam turbine, the water temperature T2 leaving the cooling water tower 6 of the condensate pump steam turbine, the condensate temperature T3 of the air-cooled island, and the condensate temperature T4 of the exhaust steam branch pipe.
[0023] The actual required circulating water volume Q1 of the condensate pump steam turbine is detected by the first condenser circulating water flow meter 12, the water temperature T1 entering the cooling water tower 6 of the condensate pump steam turbine is detected by the cooling water tower water temperature meter 16 entering the tower, the water temperature T2 leaving the cooling water tower 6 of the condensate pump steam turbine is detected by the cooling water tower water temperature meter 15 leaving the tower, the condensate temperature T3 of the air-cooled island is detected by the air-cooled island condensate temperature meter 18, and the condensate temperature T4 of the exhaust steam branch pipe is detected by the condensate temperature meter 14 of the air-cooled exhaust steam branch pipe after cooling.
[0024] Step 2: Judge whether there is cooling margin in the cooling water tower 6 of the condensate pump steam turbine according to the collected data. If there is no cooling margin, the control system closes the electric regulating valve 13 of the exhaust steam branch of the steam turbine; if there is cooling margin, calculate the exhaust steam value that can be cooled by the surplus part; The specific method is: By comparing Q1 with the rated cooling circulating water volume Q of the condensate pump steam turbine, judge whether there is cooling margin in the cooling water tower of the condensate pump steam turbine. If Q1 = Q, there is no cooling margin, and the control system closes the electric valve of the exhaust steam branch; if Q1 < Q, there is cooling margin in the cooling water tower Q0 = Q - Q1, then calculate the exhaust steam volume Q2 that can be cooled by the surplus of the cooling water tower of the condensate pump steam turbine according to the following formula:
[0025] In the formula, C is the specific heat capacity of the circulating water, H 1 is the exhaust enthalpy of the air-cooled exhaust device, T 3 is the condensate temperature of the air-cooled island, P 1 is the vacuum value of the air-cooled exhaust device, It is the enthalpy of condensed water after cooling of the exhaust device.
[0026] Step 3: Control the opening of the electric regulating valve 13 of the exhaust steam branch pipe of the steam turbine, and gradually control the system to remain stable.
[0027] The specific method is: gradually increase the opening of the electric valve of the exhaust steam branch, and compare the condensate temperature of the exhaust steam branch pipe. T 4 and air cooling island condensate temperature T 3. When T 4= T At 3 o'clock, the opening of the electric valve of the exhaust steam branch remains unchanged and the system remains stable.
[0028] The present invention proposes to utilize the surplus of the cooling tower of the cooling water of the feedwater pump turbine equipped with the air-cooling unit to cool part of the exhaust steam of the air-cooling unit through the first condenser in order to reduce the energy consumption of the air-cooling unit and improve the safe operation of the unit. This reduces the back pressure of the unit and reduces the coal consumption of the unit. At the same time, a set of automatic detection and control system is added to detect the circulating water flow rate, the water temperature of the circulating water entering the tower, the water temperature of the circulating water leaving the tower, and the condensate temperature after the air-cooling exhaust steam branch pipe is cooled at the feedwater pump turbine condenser. Through the external intelligent control system, the measured data can determine the surplus value of the cooling water tower of the feedwater pump turbine, and then calculate the exhaust steam amount that can be cooled by the exhaust steam of the turbine in the first condenser, and then control the exhaust steam of the turbine entering the first condenser through the exhaust steam pipeline valve. This set of equipment can be used in spring, autumn and winter to save the power consumption of the air-cooling fan, reduce the power consumption rate of the plant, and improve the economic efficiency of the unit operation.
[0029] Example 1 Air-wet cooling series unit device in thermal power plant, such as Figure 1 As shown, it includes an air-cooling unit and a detection control system, the air-cooling unit includes a steam turbine, the output end of the steam turbine is respectively connected to the air-cooling island 2 and the first condenser 4 through pipelines, an electric regulating valve 13 of the steam turbine exhaust steam branch pipe is arranged between the steam turbine and the first condenser 4, and the output end of the air-cooling island 2 is connected to the exhaust device 3 through a pipeline; it also includes a feedwater pump steam turbine cooling water tower 6, the output end of the feedwater pump steam turbine cooling water tower 6 is connected to the second condenser 5 through a pipeline, the output end of the second condenser 5 is connected to the first condenser 4 through a pipeline, and the output end of the first condenser 4 is respectively connected to the exhaust device 3 and the feedwater pump steam turbine cooling water tower 6 through pipelines; The detection control system is connected to the air cooling unit via a signal line.
[0030] Example 2 Air-wet cooling series unit device in thermal power plant, such as Figure 1As shown, it includes an air-cooling unit and a detection control system, the air-cooling unit includes a steam turbine, the output end of the steam turbine is respectively connected to the air-cooling island 2 and the first condenser 4 through pipelines, an electric regulating valve 13 of the steam turbine exhaust steam branch pipe is arranged between the steam turbine and the first condenser 4, and the output end of the air-cooling island 2 is connected to the exhaust device 3 through a pipeline; it also includes a feedwater pump steam turbine cooling water tower 6, the output end of the feedwater pump steam turbine cooling water tower 6 is connected to the second condenser 5 through a pipeline, the output end of the second condenser 5 is connected to the first condenser 4 through a pipeline, and the output end of the first condenser 4 is respectively connected to the exhaust device 3 and the feedwater pump steam turbine cooling water tower 6 through pipelines; Furthermore, a circulating water pump 7 and a first valve 8 are sequentially provided along the flow direction of the pipeline between the feedwater pump turbine cooling water tower 6 and the second condenser 5, and a third valve 10 is provided on the pipeline between the second condenser 5 and the first condenser 4; it also includes a second valve 9 and a fourth valve 11, one end of the second valve 9 is connected to the pipeline between the first condenser 4 and the third valve 10, and the other end of the second valve 9 is connected to the pipeline between the circulating water pump 7 and the first valve 8, one end of the fourth valve 11 is connected to the pipeline between the first condenser 4 and the third valve 10, and the other end of the fourth valve 11 is connected to the pipeline between the first condenser 4 and the feedwater pump turbine cooling water tower 6, and a second condenser circulating water flow meter 17 is provided on the pipeline between the turbine exhaust steam branch pipe electric regulating valve 13 and the first condenser 4.
[0031] The detection control system is connected to the air cooling unit via a signal line.
[0032] Example 3 The present invention provides a thermal power plant air-wet cooling series unit device, such as Figure 1 As shown, it includes an air-cooling unit and a detection control system, the air-cooling unit includes a steam turbine, the output end of the steam turbine is respectively connected to the air-cooling island 2 and the first condenser 4 through pipelines, an electric regulating valve 13 of the steam turbine exhaust steam branch pipe is arranged between the steam turbine and the first condenser 4, and the output end of the air-cooling island 2 is connected to the exhaust device 3 through a pipeline; it also includes a feedwater pump steam turbine cooling water tower 6, the output end of the feedwater pump steam turbine cooling water tower 6 is connected to the second condenser 5 through a pipeline, the output end of the second condenser 5 is connected to the first condenser 4 through a pipeline, and the output end of the first condenser 4 is respectively connected to the exhaust device 3 and the feedwater pump steam turbine cooling water tower 6 through pipelines; Furthermore, a circulating water pump 7 and a first valve 8 are sequentially provided on the pipeline between the feedwater pump turbine cooling water tower 6 and the second condenser 5 in the flow direction, and a third valve 10 is provided on the pipeline between the second condenser 5 and the first condenser 4; It also includes a second valve 9 and a fourth valve 11. One end of the second valve 9 is connected to the pipeline between the first condenser 4 and the third valve 10, and the other end of the second valve 9 is connected to the pipeline between the circulating water pump 7 and the first valve 8. One end of the fourth valve 11 is connected to the pipeline between the first condenser 4 and the third valve 10, and the other end of the fourth valve 11 is connected to the pipeline between the first condenser 4 and the feed water pump turbine cooling water tower 6. A second condenser circulating water flow meter 17 is provided on the pipeline between the turbine exhaust steam branch pipe electric regulating valve 13 and the first condenser 4.
[0033] The detection control system is connected to the air-cooling unit through a signal line. Specifically, the detection control system includes a condensate temperature measuring meter 14 for the air-cooled exhaust steam branch pipe after cooling, a water temperature measuring meter 15 for the cooling water tower outlet, a water temperature measuring meter 16 for the cooling water tower inlet, and a condensate temperature measuring meter 18 for the air-cooled island. The condensate temperature measuring meter 14 for the air-cooled exhaust steam branch pipe after cooling is arranged on the pipeline between the first condenser 4 and the exhaust device 3, and the condensate temperature measuring meter 18 for the air-cooled island is arranged between the air-cooled island 2 and the exhaust device 3. On the pipeline, the cooling water tower outlet water temperature measuring meter 15 is arranged on the pipeline between the circulating water pump 7 and the first valve 8, the cooling water tower inlet water temperature measuring meter 16 is arranged on the pipeline between the first condenser 4 and the feed water pump turbine cooling water tower 6, the condensed water temperature measuring meter 14 after cooling of the air-cooled exhaust steam branch pipe, the cooling water tower outlet water temperature measuring meter 15, the cooling water tower inlet water temperature measuring meter 16 and the air-cooled island condensed water temperature measuring meter 18 are all connected to the turbine exhaust steam branch pipe electric regulating valve 13 through a signal line; It also includes a first condenser circulating water flow meter 12, which is located between the first valve 8 and the second condenser 5. The first condenser circulating water flow meter 12 is connected to the turbine exhaust steam branch pipe electric regulating valve 13 through a signal line.
[0034] Example 4 Control optimization operation method of air-wet cooling series units in thermal power plants, such as Figure 2 As shown, the specific method is as follows: Step 1: Collect relevant data through the detection and control system; Step 1: Collect relevant data through the detection and control system; The collected data include: the actual circulating water volume Q1 required by the feedwater pump turbine, the water inlet temperature T1 of the feedwater pump turbine cooling water tower 6, the water outlet temperature T2 of the feedwater pump turbine cooling water tower 6, the condensate temperature T3 of the air cooling island, and the condensate temperature T4 of the exhaust steam branch pipe.
[0035] The actual circulating water volume Q1 required by the feed water pump steam turbine is detected by the circulating water flow meter 12 of the first condenser. The inlet water temperature T1 of the cooling water tower 6 of the feed water pump steam turbine is detected by the inlet water temperature meter 16 of the cooling water tower. The outlet water temperature T2 of the cooling water tower 6 of the feed water pump steam turbine is detected by the outlet water temperature meter 15 of the cooling water tower. The condensate temperature T3 of the air-cooled island is detected by the condensate temperature meter 18 of the air-cooled island, and the condensate temperature T4 of the exhaust steam branch pipe is detected by the condensate temperature meter 14 of the cooled condensate of the air-cooled exhaust steam branch pipe.
[0036] Step 2: Determine whether there is cooling margin for the cooling water tower 6 of the feed water pump steam turbine according to the collected data. If there is no cooling margin, the control system closes the electric regulating valve 13 of the exhaust steam branch pipe of the steam turbine; if there is cooling margin, calculate the exhaust steam value that can be cooled by the surplus part; Step 3: Control the opening of the electric regulating valve 13 of the exhaust steam branch pipe of the steam turbine, and gradually keep the control system stable.
[0037] Embodiment 5 The control and optimization operation method of the air-cooled and wet-cooled series unit in a thermal power plant is as Figure 2 shown, and the specific method is as follows: Step 1: Collect relevant data through the detection control system; Step 2: Determine whether there is cooling margin for the cooling water tower 6 of the feed water pump steam turbine according to the collected data. If there is no cooling margin, the control system closes the electric regulating valve 13 of the exhaust steam branch pipe of the steam turbine; if there is cooling margin, calculate the exhaust steam value that can be cooled by the surplus part; The specific method is: By comparing Q1 with the rated cooling circulating water volume Q of the feed water pump steam turbine, determine whether there is cooling margin for the cooling water tower of the feed water pump steam turbine. If Q1 = Q, there is no cooling margin, and the control system closes the electric valve of the exhaust steam branch; if Q1 < Q, there is cooling margin Q0 = Q - Q1, then calculate the exhaust steam volume Q2 that can be cooled by the surplus of the cooling water tower of the feed water pump steam turbine according to the following formula:
[0038] In the formula, C is the specific heat capacity of circulating water, H 1 is the exhaust enthalpy of the air-cooled exhaust device, T 3 is the condensate temperature of the air-cooled island, P 1 is the vacuum value of the air-cooled exhaust device, is the enthalpy value of the condensate after cooling by the exhaust device.
[0039] Step 3: Control the opening of the electric regulating valve 13 of the exhaust steam branch pipe of the steam turbine, and gradually keep the control system stable.
[0040] Embodiment 6 The control and optimization operation method of the air-cooled and wet-cooled series unit in a thermal power plant is as Figure 2As shown, the specific method is as follows: Step 1: Collect relevant data through the detection and control system; Step 2: determine whether the cooling water tower 6 of the feedwater pump turbine has cooling margin according to the collected data. If there is no cooling margin, the control system closes the electric regulating valve 13 of the turbine exhaust steam branch pipe; if there is cooling margin, calculate the exhaust steam value that can be cooled by the margin; Step 3: Control the opening of the electric regulating valve 13 of the exhaust steam branch of the steam turbine, and gradually control the system to remain stable. The specific method is: gradually increase the opening of the electric valve of the exhaust steam branch, and at the same time compare the condensate temperature of the exhaust steam branch. T 4 and air cooling island condensate temperature T 3. When T 4= T At 3 o'clock, the opening of the electric valve of the exhaust steam branch remains unchanged and the system remains stable.
Claims
1. Air-wet cooling series unit device for thermal power plant, characterized in that: The air-cooling unit comprises an air-cooling unit and a detection control system, wherein the air-cooling unit comprises a steam turbine (1), wherein the output end of the steam turbine (1) is respectively connected to an air-cooling island (2) and a first condenser (4) via pipelines, wherein a steam turbine exhaust steam branch pipe electric regulating valve (13) is provided between the steam turbine (1) and the first condenser (4), and the output end of the air-cooling island (2) is connected to an exhaust device (3) via a pipeline; and further comprises a feedwater pump steam turbine cooling water tower (6), wherein the output end of the feedwater pump steam turbine cooling water tower (6) is connected to a second condenser (5) via a pipeline, wherein the output end of the second condenser (5) is connected to the first condenser (4) via a pipeline, and wherein the output end of the first condenser (4) is respectively connected to the exhaust device (3) and the feedwater pump steam turbine cooling water tower (6) via pipelines; The detection control system is connected to the air cooling unit via a signal line.
2. According to claim 1, the air-wet cooling series unit device of a thermal power plant is characterized in that: A circulating water pump (7) and a first valve (8) are provided in sequence along the flow direction on the pipeline between the feedwater pump turbine cooling water tower (6) and the second condenser (5), and a third valve (10) is provided on the pipeline between the second condenser (5) and the first condenser (4); It also includes a second valve (9) and a fourth valve (11), wherein one end of the second valve (9) is connected to the pipeline between the first condenser (4) and the third valve (10), and the other end of the second valve (9) is connected to the pipeline between the circulating water pump (7) and the first valve (8); one end of the fourth valve (11) is connected to the pipeline between the first condenser (4) and the third valve (10), and the other end of the fourth valve (11) is connected to the pipeline between the first condenser (4) and the feedwater pump turbine cooling water tower (6); and a second condenser circulating water flow meter (17) is provided on the pipeline between the turbine exhaust steam branch pipe electric regulating valve (13) and the first condenser (4).
3. The air-wet cooling series unit device of a thermal power plant according to claim 2 is characterized in that: The detection and control system comprises a condensed water temperature measuring meter (14) after cooling of the air-cooled exhaust steam branch pipe, a water temperature measuring meter (15) at the outlet of the cooling water tower, a water temperature measuring meter (16) at the inlet of the cooling water tower, and a condensed water temperature measuring meter (18) at the air-cooled island. The condensed water temperature measuring meter (14) after cooling of the air-cooled exhaust steam branch pipe is arranged on the pipeline between the first condenser (4) and the exhaust device (3), the condensed water temperature measuring meter (18) at the air-cooled island is arranged on the pipeline between the air-cooled island (2) and the exhaust device (3), and the outlet of the cooling water tower is arranged on the outlet of the cooling water tower. The water temperature measuring meter (15) is arranged on the pipeline between the circulating water pump (7) and the first valve (8); the cooling water tower inlet water temperature measuring meter (16) is arranged on the pipeline between the first condenser (4) and the feedwater pump turbine cooling water tower (6); the air-cooled exhaust steam branch pipe cooling condensate water temperature measuring meter (14), the cooling water tower outlet water temperature measuring meter (15), the cooling water tower inlet water temperature measuring meter (16) and the air-cooled island condensate water temperature measuring meter (18) are all connected to the turbine exhaust steam branch pipe electric regulating valve (13) via a signal line; It further includes a first condenser circulating water flow meter (12), the first condenser circulating water flow meter (12) is located between the first valve (8) and the second condenser (5), and the first condenser circulating water flow meter (12) is connected to the electric regulating valve (13) of the steam turbine exhaust branch through a signal line.
4. The control optimization operation method of the air-wet cooling series unit in a thermal power plant as described in claims 1 to 3 is characterized in that: The specific method is as follows: Step 1: Collect relevant data through the detection control system; Step 2: Judge whether there is cooling margin for the feed water pump steam turbine cooling water tower (6) according to the collected data. If there is no cooling margin, the control system closes the electric regulating valve (13) of the steam turbine exhaust branch; if there is cooling margin, calculate the exhaust steam value that can be cooled by the surplus part. Step 3: Control the opening of the electric regulating valve (13) of the steam turbine exhaust branch and gradually keep the control system stable.
5. The control optimization operation method of the air-wet cooling series unit in a thermal power plant according to claim 4 is characterized in that: The data collected in Step 1 includes: the actual circulating water volume Q1 required by the feed water pump steam turbine, the inlet water temperature T1 of the feed water pump steam turbine cooling water tower (6), the outlet water temperature T2 of the feed water pump steam turbine cooling water tower (6), the condensate temperature T3 of the air-cooled island, and the condensate temperature T4 of the exhaust steam branch.
6. The control optimization operation method of the air-wet cooling series unit in a thermal power plant according to claim 5 is characterized in that: The actual circulating water volume Q1 required by the feed water pump steam turbine is detected by the first condenser circulating water flow meter (12), the inlet water temperature T1 of the feed water pump steam turbine cooling water tower (6) is detected by the cooling water tower inlet water temperature meter (16), the outlet water temperature T2 of the feed water pump steam turbine cooling water tower (6) is detected by the cooling water tower outlet water temperature meter (15), the condensate temperature T3 of the air-cooled island is detected by the air-cooled island condensate temperature meter (18), and the condensate temperature T4 of the exhaust steam branch is detected by the condensate temperature meter (14) after the air-cooled exhaust steam branch is cooled.
7. The control optimization operation method of the air-wet cooling series unit in a thermal power plant according to claim 5 is characterized in that: The specific method of Step 2 is: By comparing Q1 and the rated cooling circulating water volume Q of the feed water pump steam turbine, judge whether there is cooling margin for the feed water pump steam turbine cooling water tower. If Q1 = Q, there is no cooling margin, and the control system closes the electric valve of the exhaust steam branch; if Q1 < Q, there is cooling margin Q0 = Q - Q1 for the cooling water tower, and then calculate the exhaust steam volume Q2 that can be cooled by the surplus of the feed water pump steam turbine cooling water tower according to the following formula: （1） Where C is the specific heat capacity of circulating water, H 1 is the exhaust enthalpy of the air-cooled exhaust device, T 3 is the condensation water temperature of the air cooling island, P 1 is the vacuum value of the air-cooled exhaust device, It is the enthalpy of condensed water after cooling of the exhaust device.
8. The control optimization operation method of the air-wet cooling series unit in a thermal power plant according to claim 7 is characterized in that: The specific method of step 3 is: gradually increase the opening of the electric valve of the exhaust steam branch, and at the same time compare the condensate temperature of the exhaust steam branch pipe T 4 and air cooling island condensate temperature T 3. When T 4= T At 3 o'clock, the opening of the electric valve of the exhaust steam branch remains unchanged and the system remains stable.