Automatic switching management system and method for high-pressure and low-pressure heaters of thermal power plant

Abstract

The invention discloses an automatic switching management system and method for high and low pressure heaters of a thermal power plant, and the method comprises the steps: firstly, carrying out the statistics of the starting and stopping important state information of a unit and the DCS measurement points of the high and low pressure heaters based on a DCS system, determining the initial states of the high and low pressure heaters, and enabling the automatic switching management system to determine whether to switch on or switch off according to the set requirements, the management system is embedded with control boundary parameters of the high and low pressure heaters and a commissioning and retreating control flow and execution steps specified by industrial regulations, and can ensure that the unit always operates stably and orderly in the execution process. According to the invention, safe switching and retreating and process management during random starting and stopping of the high-pressure heater and the low-pressure heater of the thermal power plant can be realized, and on-line automatic switching-off and switching-on can also be realized when defects related to the high-pressure heater and the low-pressure heater are handled during operation of the unit. The operation safety and reliability of the high-pressure heater and the low-pressure heater are improved through all the automatic switching whole processes, and complexity and uncertainty of manual control are replaced.

Description

Technical Field

[0001] The present invention relates to the technical field of the power industry, and particularly relates to an automatic switching management system and method for high and low pressure heaters in a thermal power plant. Background Art

[0002] The high and low pressure heaters in a thermal power plant are important auxiliary equipment for improving the thermal efficiency of the unit and optimizing the operating conditions. During the start-up, shutdown and operation of the unit, how to reasonably switch the high and low pressure heaters is a key link to ensure the safe and stable operation of the unit. Traditional heater switching operations mostly rely on manual control, which is not only cumbersome, but also prone to premature or delayed switching of the heaters due to human judgment errors, thus affecting the stability of the unit operation and even posing potential safety hazards.

[0003] There has been a patent proposing a method for putting into operation a high pressure heater. However, due to the large differences in high and low pressure heaters and their auxiliary equipment in a thermal power plant, the operation methods are different, and no automatic switching function is proposed. Summary of the Invention

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

[0005] The present invention proposes an automatic switching management system for high and low pressure heaters in a thermal power plant, which has embedded the control boundary parameters of high and low pressure heaters and the switching control processes and execution steps specified in industry regulations, and can ensure that the unit always operates smoothly and orderly during the execution process.

[0006] Another object of the present invention is to propose an automatic switching management method for high and low pressure heaters in a thermal power plant.

[0007] To achieve the above object, on the one hand, the present invention proposes an automatic switching management system for high and low pressure heaters in a thermal power plant, including:

[0008] A measured point data acquisition module, which is used to automatically collect the state information during the start-up and shutdown of the unit and the real-time measured point data of the high and low pressure heater systems according to the set requirements based on the DCS system, and automatically judge the initial states of the high and low pressure heaters;

[0009] A control module, which is used to start and execute as required according to the preset control boundary parameters and switching processes after the automatic switching management system is started;

[0010] An equipment control module, which is used to judge the switching timing of the high and low pressure heaters according to the preset switching control conditions, and automatically control the opening and closing of the execution valves and the linkage of the equipment;

[0011] The parameter monitoring module is used to collect the operating parameters of the high and low pressure heaters in real time, so as to monitor the status of the equipment during the commissioning and decommissioning process and adjust the operation process according to the monitoring data;

[0012] Automatic start-up and shutdown module, used to automatically shut down the high-pressure and low-pressure heaters during unit operation, creating conditions for handling heater-related defects, and automatically restart the heaters after the fault is eliminated;

[0013] Optimization control module, used to optimize control logic online and modify control parameters.

[0014] The method for automatically switching on and off high- and low-pressure heaters in a thermal power plant according to an embodiment of the present invention may also have the following additional technical features:

[0015] In one embodiment of the present invention, the method further includes:

[0016] Initialize the automatic start and stop operation interface module of high and low pressure heaters in thermal power plants;

[0017] Switch between automatic and manual modes, and dynamically adjust the control mode based on user input or system requirements;

[0018] By reading the device status information, updating and displaying the indicator light or label, reflecting the current working status of the device;

[0019] Execute each step in a preset process and handle step order and step skipping functions as needed, allowing you to skip specific steps or continue to the next step in multi-step automation tasks;

[0020] Provides a time parameter setting interface for timing operations or recording process time consumption to ensure that operations meet the predetermined time requirements;

[0021] Monitor and respond to input from universal operation buttons to directly control the start, stop, and reset of equipment.

[0022] In one embodiment of the present invention, whether the high-voltage heater meets the conditions for being put into operation is automatically determined through logic.

[0023] In one embodiment of the present invention, the automatic activation and adjustment of the high-voltage heater are performed through multi-step control, condition judgment, input-output state association, and global tag management.

[0024] In one embodiment of the present invention, whether the high-voltage heater is allowed to exit is automatically determined through logic, including automatic adjustment and safety monitoring mechanisms to ensure that no adverse consequences will occur when the high-voltage heater automatically exits.

[0025] In one embodiment of the present invention, the automatic startup of the equipment is performed through step-by-step control, condition judgment, time delay and status feedback.

[0026] In one embodiment of the present invention, through step-by-step control, input / output condition judgment, equipment control and feedback, it is ensured that the equipment runs smoothly and step by step; each step adjusts the operation according to the equipment status and real-time parameters.

[0027] To achieve the above object, on the other hand, the present invention proposes an automatic switching management method for high and low pressure heaters in a thermal power plant, including:

[0028] According to the set requirements, collect the status information during the start-up and shutdown of the unit and the real-time measured data of the high and low pressure heater systems, and automatically judge the initial status of the high and low pressure heaters;

[0029] According to the preset control boundary parameters and switching processes, start and execute as required, and judge the switching timing of the high and low pressure heaters according to the preset switching control conditions, and automatically control the opening and closing of the execution valves and equipment linkage;

[0030] Real-time collect the operation parameters of the high and low pressure heaters through the parameter monitoring module, so as to monitor the status of the equipment during the switching process, and adjust the operation process according to the monitoring data;

[0031] Automatically withdraw the high and low pressure heaters during the operation of the unit to create conditions for dealing with heater-related defects, and automatically re-insert the heaters after troubleshooting; and,

[0032] Online optimize the control logic and modify the control parameters.

[0033] The automatic switching management system and method for high and low pressure heaters in the thermal power plant according to the embodiments of the present invention utilize the present invention to realize the safe switching and process management of high and low pressure heaters in the thermal power plant during the start-up and shutdown of the unit, and can also realize the online automatic withdrawal and insertion during the operation of the unit when dealing with defects related to high and low pressure heaters. The entire automatic switching process improves the operation safety and reliability of high and low pressure heaters, replacing the cumbersome and uncertain manual control.

[0034] The additional aspects and advantages of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the following description of the embodiments in conjunction with the drawings, where:

[0036] Figure 1 is a structural diagram of an automatic switching management system for high and low pressure heaters in a thermal power plant according to an embodiment of the present invention;

[0037] Figure 2It is the automatic start-up and shutdown operation interface diagram of high and low pressure heaters used according to the embodiments of the present invention;

[0038] Figure 3 It is the logic diagram for automatically judging and confirming whether the high pressure heater is ready for startup according to the embodiments of the present invention;

[0039] Figure 4 It is a kind of automatic start-up logic diagram of high pressure heaters according to the embodiments of the present invention;

[0040] Figure 5 It is a kind of automatic shutdown logic diagram of high pressure heaters according to the embodiments of the present invention;

[0041] Figure 6 It is a kind of automatic start-up logic diagram of low pressure heaters according to the embodiments of the present invention;

[0042] Figure 7 It is another kind of automatic start-up logic diagram of low pressure heaters according to the embodiments of the present invention. Detailed implementation manners

[0043] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0044] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0045] The automatic start-up and shutdown management system and method of high and low pressure heaters in thermal power plants proposed according to the embodiments of the present invention will be described below with reference to the drawings.

[0046] Figure 1 It is the structural diagram of the automatic start-up and shutdown management system of high and low pressure heaters in thermal power plants according to the embodiments of the present invention. As Figure 1 shown, it includes:

[0047] The measuring point data acquisition module 100 is used to automatically acquire the state information during the start-up and shutdown of the unit and the real-time measuring point data of the high and low pressure heater systems based on the DCS system according to the set requirements by the automatic start-up and shutdown management system, and automatically judge the initial states of the high and low pressure heaters;

[0048] The control module 200 is used to, after the automatic start-up and shutdown management system is started, the control module starts and executes as required according to the preset control boundary parameters and start-up and shutdown processes;

[0049] The equipment control module 300 is used to judge the commissioning and decommissioning timing of the high- and low-pressure heaters according to the preset commissioning and decommissioning control conditions, and automatically control the opening and closing of the execution valves and the linkage of the equipment.

[0050] The parameter monitoring module 400 is used to collect the operation parameters of the high- and low-pressure heaters in real time, so as to monitor the state of the equipment during the commissioning and decommissioning process, and adjust the operation process according to the monitoring data.

[0051] The automatic commissioning and decommissioning module 500 is used to automatically decommission the high- and low-pressure heaters during the operation of the unit, create conditions for dealing with heater-related defects, and automatically re-enter the heaters after troubleshooting.

[0052] The optimization control module 600 is used to optimize the control logic online and modify the control parameters.

[0053] Specifically, based on the DCS system, the automatic commissioning and decommissioning management system first collects the status information during the start-up and shutdown processes of the unit and the real-time measurement point data of the high- and low-pressure heater systems according to the set requirements, and automatically judges the initial state of the high- and low-pressure heaters.

[0054] [[ID=!17]]After the automatic commissioning and decommissioning management system is started, the control module automatically executes the commissioning or decommissioning operation of the heater according to the preset control boundary parameters and commissioning and decommissioning processes, and ensures the stability during the start-up, shutdown and operation of the unit.

[0055] The equipment control module judges the commissioning and decommissioning timing of the high- and low-pressure heaters according to the preset commissioning and decommissioning control conditions, and automatically controls the opening and closing of the execution valves and the linkage of the equipment. The parameter monitoring module collects the operation parameters of the high- and low-pressure heaters in real time to ensure that the state of the equipment can be accurately monitored during the commissioning and decommissioning process, and adjusts the operation process according to the monitoring data.

[0056] Automatically decommission the high- and low-pressure heaters during the operation of the unit, create conditions for dealing with heater-related defects, and automatically re-enter the heaters after troubleshooting.

[0057] The present invention can optimize the control logic online, modify the control parameters, and ensure the matching of system control with the actual situation of the unit.

[0058] The present invention automatically executes the commissioning and decommissioning operations of the heaters step by step in strict accordance with the operation process to ensure the accuracy and safety of each operation.

[0059] In an embodiment of the present invention, as Figure 2 shown, it is the automatic commissioning and decommissioning operation interface of the high- and low-pressure heaters in a thermal power plant, which is suitable for programmed control, status monitoring and multi-mode switching.

[0060] 2) Support the switching between "automatic" and "manual" modes to meet the control requirements under different working conditions.

[0061] 3) Intuitively display the current status of the device through indicators or labels such as "Running", "Fault", "Paused", "Completed", etc.

[0062] 4) Include "Step Sequence" and "Step Skipping" functions, which can execute preset processes or skip specific steps, suitable for multi-step automated tasks.

[0063] 5) Provide "Time" parameter setting for timed operations or recording the time consumption of processes.

[0064] 6) Equipped with general operation buttons such as "Start", "Pause", "Reset", etc., facilitating direct control of the device's start / stop and reset.

[0065] In an embodiment of the present invention, it is automatically judged logically to confirm whether the high-pressure heater meets the input conditions. As Figure 3 shown.

[0066] In an embodiment of the present invention, through multi-step control, flexible condition judgment, input / output status association, and global label management, precise control and automatic adjustment of the automatic input of the high-pressure heater are achieved, as Figure 4 shown.

[0067] Figure 3 , Figure 4 , #1, 2, and 3 high-pressure heaters are put into program control, and the specific logic is as follows:

[0068] Start permission (AND):

[0069] The unit has been grid-connected;

[0070] The water side of the high-pressure heater has been put into operation (the outlet motorized valve of #1 high-pressure heater is open and the inlet three-way motorized valve of the high-pressure heater is open).

[0071] Step 1

[0072] Action: Open the drain valves of the first, second, and third stage extraction steam pipelines.

[0073] Feedback: The drain valves before the extraction steam motorized valves and after the check valves of the first, second, and third stages are all open.

[0074] Step 2

[0075] Action: Open the check valves of the first, second, and third stage extraction steam;

[0076] Feedback: The check valves of the first, second, and third stage extraction steam are all open.

[0077] Step 3

[0078] Action: Fully open the accident drain regulating valves of #1, 2, and 3 high-pressure heaters;

[0079] Fully close the normal drain regulating valve of #3 high-pressure heater.

[0080] Feedback (AND):

[0081] #1, 2, and 3 high pressure heater accident drain regulating valve positions are all > 95%;

[0082] #3 high pressure heater normal drain regulating valve position < 5%.

[0083] Step 4

[0084] Action: When the first, second, and third stage extraction steam motorized valve positions ≤ 40%, open the first, second, and third stage extraction steam motorized valves at a speed of opening 1 s every 30 s. When the first, second, and third stage extraction steam motorized valve positions > 40%, open the first, second, and third stage extraction steam motorized valves at a speed of opening 1 s every 10 s.

[0085] Note:

[0086] After the extraction steam motorized valve leaves the closed position, start monitoring the temperature rise rate at the outlets of #1, 2, and 3 high pressure heaters ≤ 100 °C / h for 5 min. Otherwise, stop opening the valve;

[0087] After the extraction steam motorized valve leaves the closed position, start monitoring the steam temperature rise rate after the first, second, and third stage extraction steam check valves > 10 °C / min for 5 min, or the temperature difference between the temperature in front of the motorized valve and the temperature after the check valve is less than 5 °C. Otherwise, stop opening the valve.

[0088] Feedback (AND):

[0089] The temperature differences before and after the first, second, and third stage extraction steam valves are all < 5 °C;

[0090] The first, second, and third stage extraction steam motorized valves are all in the fully open position.

[0091] Step 5

[0092] Action: Close the #1 and 2 high pressure heater accident drain regulating valves at a rate of 5% / min;

[0093] Feedback: The water levels of #1 and 2 high pressure heaters are both > -200 mm. At this time, stop closing the accident drain regulating valves.

[0094] Step 6

[0095] Action: Put the #1 and 2 high pressure heater normal drain regulating valves into automatic, and set the set values of the #1 and 2 low pressure heater normal drain regulating valves to -230 mm at a rate of 20 mm / min.

[0096] Feedback (AND):

[0097] The #1 and 2 high pressure heater normal drain regulating valves are both in the automatic position;

[0098] The water levels of #1 and 2 high pressure heaters are both stable at -230 mm (±50) and maintained for 3 min.

[0099] Step 7

[0100] Action: Put the #1 and 2 high pressure emergency drain regulating valves into automatic operation and set the set value of the #1 and 2 high pressure emergency drain regulating valves to 50mm at a rate of 50mm / min.

[0101] Feedback (with):

[0102] The emergency drain regulating valves of #1 and #2 high pressure heaters are both in the automatic position;

[0103] The valve positions of #1 and #2 high pressure heater emergency drain regulating valves are both less than 5%;

[0104] The tertiary extraction pressure is at least 0.2MPa higher than the deaerator pressure;

[0105] The steam supply to the deaerator has been diverted to the fourth extraction.

[0106] Step 8: Start the #3 high pressure normal drain regulating valve automatically, and the water level setting value is the current value;

[0107] Close the #3 high pressure emergency drain regulating valve at a rate of 5% / min.

[0108] Feedback (with):

[0109] #3 High pressure heater normal drain regulating valve is in automatic position;

[0110] #3 High water level>-200mm.

[0111] Step 9: Set the set value of the #1 high pressure normal drain valve to 0mm feedback (and) at a rate of 20mm / min:

[0112] #1 High Pressure Heater Normal Drain Regulating Valve is in the automatic position;

[0113] #1 High water level is stabilized at 0mm (±50) and maintained for 3 minutes.

[0114] Step 10: Set the set point of the #2 high pressure normal drain valve to 0mm feedback (and) at a rate of 20mm / min:

[0115] #2 High pressure heater normal drain regulating valve is in automatic position;

[0116] #2 The high water level is stabilized at 0mm (±50) and maintained for 3 minutes.

[0117] Step 11: Set the set value of the #3 high pressure normal drain regulating valve to 0mm at a rate of 20mm / min;

[0118] Put #3 high pressure heater emergency drain regulating valve into automatic operation;

[0119] Set the set value of the #3 high-pressure heater accident drainage regulating valve to 50 mm at a rate of 50 mm / min. Feedback (AND):

[0120] The normal drainage and accident drainage regulating valves of the #3 high-pressure heater are both in the automatic position;

[0121] The valve position of the #3 high-pressure heater accident drainage regulating valve < 5%;

[0122] The water level of the #3 high-pressure heater is stable at 0 mm (±50) and maintained for 5 minutes.

[0123] Step 12

[0124] Action: Close the drain valves of the first, second, and third stage extraction steam pipelines.

[0125] Feedback: The drain valves before and after the first, second, and third stage extraction steam valves are all closed.

[0126] In an embodiment of the present invention, it is automatically judged by logic whether the high-pressure heater is allowed to be withdrawn, including an automatic adjustment and safety monitoring mechanism to ensure that no adverse consequences will occur when the high-pressure heater is automatically withdrawn. For example, through the change of the sensor status, the system can automatically judge and adjust the operation to ensure the safe shutdown of the equipment. As Figure 5 shown.

[0127] Figure 5 :#1, 2, 3 high-pressure heaters are withdrawn from the program control, and the specific logic is as follows:

[0128] Startup permission (AND):

[0129] The unit load is between 300 - 500 MW.

[0130] Step 1

[0131] Action: Release the automatic control of the #1 high-pressure heater accident drainage regulating valve;

[0132] Open the #1 high-pressure heater accident drainage regulating valve at a rate of 4% / min.

[0133] Feedback (AND):

[0134] The #1 high-pressure heater accident drainage regulating valve is in the automatic position;

[0135] The water level of the #1 high-pressure heater drops significantly (the actual water level is more than 100 mm lower than the normal regulating valve set value);

[0136] The valve position of the #1 high-pressure heater accident drainage regulating valve is greater than 95%.

[0137] Step 2

[0138] Action: Close the first stage extraction steam motorized valve at a speed of opening for 1 s every 20 s;

[0139] Note:

[0140] 1) After the extraction steam motor-operated valve leaves the open position, start to monitor that the temperature drop rate at the outlet of the #1 high-pressure heater ≤ 100 °C / h for 5 minutes. Otherwise, stop closing the valve.

[0141] 2) To ensure sufficient reduction of steam flow rate, when the opening of the first-stage extraction steam motor-operated valve > 90%, the logic in 1) above does not work.

[0142] Feedback: The first-stage extraction steam motor-operated valve has been closed.

[0143] Step 3

[0144] Action: Release the automatic control of the normal drain regulating valve of the #1 high-pressure heater and fully close it at a speed of 4% / min.

[0145] Close the first-stage extraction steam check valve.

[0146] Feedback:

[0147] The valve position of the normal drain regulating valve of the #1 high-pressure heater < 5%.

[0148] The first-stage extraction steam check valve has been closed.

[0149] Step 4

[0150] Action: Release the automatic control of the emergency drain regulating valve of the #2 high-pressure heater.

[0151] Open the emergency drain regulating valve of the #2 high-pressure heater at a rate of 4% / min.

[0152] Feedback (AND):

[0153] The emergency drain regulating valve of the #2 high-pressure heater is in the automatic position.

[0154] The water level of the #2 high-pressure heater drops significantly (the actual water level is more than 100 mm below the normal regulating valve setting value).

[0155] The valve position of the emergency drain regulating valve of the #2 high-pressure heater is greater than 95%.

[0156] Step 5

[0157] Action: Close the second-stage extraction steam motor-operated valve at a speed of opening for 1 s every 20 s.

[0158] Note:

[0159] 1) After the extraction steam motor-operated valve leaves the open position, start to monitor that the temperature drop rate at the outlet of the #2 high-pressure heater ≤ 100 °C / h for 5 minutes. Otherwise, stop closing the valve.

[0160] 2) To ensure sufficient reduction of steam flow rate, when the opening of the second-stage extraction steam motor-operated valve > 90%, the logic in 1) above does not work.

[0161] Feedback: The second-stage extraction steam motor-operated valve has been closed.

[0162] Step 6

[0163] Action: Release the automatic control of the #2 high-pressure normal drain regulating valve and fully close it at a rate of 4% / min;

[0164] Close the non-return valve of the second-stage extraction steam.

[0165] Feedback:

[0166] The valve position of the #2 high-pressure heater normal drain regulating valve < 5%;

[0167] The non-return valve of the second-stage extraction steam has been closed.

[0168] Step 7

[0169] Action: Release the automatic control of the #3 high-pressure heater emergency drain regulating valve;

[0170] Open the #3 high-pressure heater emergency drain regulating valve at a rate of 4% / min.

[0171] Feedback (and):

[0172] The #3 high-pressure heater emergency drain regulating valve is in the automatic position;

[0173] The water level of the #3 high-pressure heater drops significantly (the actual water level is more than 100 mm below the normal regulating valve setting value);

[0174] The valve position of the #3 high-pressure heater emergency drain regulating valve is greater than 95%.

[0175] Step 8 [[ID=4%3]]

[0176] Action: Close the electric valve of the third-stage extraction steam at a speed of opening for 1 s every 20 s;

[0177] Note:

[0178] 1) After the electric valve of the extraction steam leaves the open position, start monitoring that the temperature drop rate at the outlet of the #3 high-pressure heater ≤ 100 °C / h for 5 min, otherwise stop closing the valve;

[0179] 2) To ensure sufficient reduction of the steam flow rate, when the opening of the electric valve of the third-stage extraction steam > 90%, the above logic in 1) does not work.

[0180] Feedback: The electric valve of the third-stage extraction steam has been closed.

[0181] Step 9

[0182] Action: Release the automatic control of the #3 high-pressure normal drain regulating valve and fully close it at a rate of 4% / min;

[0183] Close the non-return valve of the third-stage extraction steam.

[0184] Feedback:

[0185] The valve position of the normal drain regulating valve of the #3 high-pressure heater is < 5%;

[0186] The check valve of the extraction steam of the third stage has been closed.

[0187] In one embodiment of the present invention, the #5 and #6 low-pressure heaters are automatically put into operation: the automatic start-up of the equipment is achieved through step-by-step control, condition judgment, time delay, and status feedback. The system ensures that the equipment can start smoothly and safely in each step. At the same time, automatic regulation and safety monitoring ensure the high efficiency and safety of the equipment during the entire start-up process. As Figure 6 shown.

[0188] Figure 6 : The #5 and #6 low-pressure heaters are put into program control, and the specific logic is as follows:

[0189] Start permission (AND):

[0190] The turbine is fixed at a speed of 2000 ± 10 rpm;

[0191] The vacuum of the condenser is < -75 kPa;

[0192] The automatic water level control of the #7 and #8 low-pressure heaters has been put into operation;

[0193] The water side of the #5 low-pressure heater has been put into operation (the inlet motorized valve and the outlet motorized valve of the water side of the #5 low-pressure heater are open, and the bypass motorized valve is closed);

[0194] The water side of the #6 low-pressure heater has been put into operation (the inlet motorized valve and the outlet motorized valve of the water side of the #6 low-pressure heater are open, and the bypass motorized valve is closed).

[0195] Step 1

[0196] Action: Open the drain valves of the extraction steam pipelines of the fifth and sixth stages.

[0197] Feedback: The drain valves in front of the extraction steam motorized valves of the fifth and sixth stages and behind the check valves are all open.

[0198] Step 2

[0199] Action: Fully open the emergency drain regulating valves of the #5 and #6 low-pressure heaters and switch to manual;

[0200] Fully open the normal drain regulating valves of the #5 and #6 low-pressure heaters and switch to manual;

[0201] Feedback (AND):

[0202] The emergency drain valves and normal drain valves of the #5 and #6 low-pressure heaters are all in the automatic position;

[0203] The valve positions of the emergency drain valves of the #5 and #6 low-pressure heaters are both > 95%;

[0204] The valve positions of the normal drain valves of the #5 and #6 low-pressure heaters are both < 5%.

[0205] Step 3

[0206] Action: Open the non-return valves of the fifth and sixth stage extraction steam.

[0207] Feedback: The non-return valves of the fifth and sixth stage extraction steam are both open.

[0208] Step 4

[0209] Action: Open the electric valves of the fifth and sixth stage extraction steam at a speed of opening for 1 s every 10 s interval.

[0210] Note:

[0211] After the extraction steam electric valve leaves the closed position, start monitoring the temperature rise rate at the outlets of #5 and 6 low-pressure heaters ≤ 120 °C / h for 5 min, otherwise stop opening the valve;

[0212] After the extraction steam electric valve leaves the closed position, start monitoring the steam temperature rise rate after the non-return valves of the fifth and sixth stage extraction steam greater than 10 °C / min for 5 min, or the temperature difference between the front of the electric valve and the back of the non-return valve is less than 5 °C, otherwise stop opening the valve;

[0213] Within the first 35 s of valve opening, in order to ensure sufficient steam flow, the above 1) and 2) logics do not take effect.

[0214] Feedback (AND):

[0215] The temperature difference before and after the fifth stage extraction steam valve < 5 °C;

[0216] The temperature difference before and after the sixth stage extraction steam valve < 5 °C;

[0217] The electric valves of the fifth and sixth stage extraction steam are both in the fully open position.

[0218] Step 5

[0219] Action: Close the accident drain regulating valves of #5 and 6 low-pressure heaters at a rate of 10% / min;

[0220] Feedback: The water levels of #5 and 6 low-pressure heaters are both > -200 mm. At this time, stop closing the accident drain regulating valves.

[0221] Step 6

[0222] Action: Put the normal drain regulating valves of #5 and 6 low-pressure heaters into automatic, and set the set values of the normal drain regulating valves of #5 and 6 low-pressure heaters to -230 mm at a rate of 20 mm / min.

[0223] Feedback (AND):

[0224] The normal drain regulating valves of #5 and 6 low-pressure heaters are both in the automatic position;

[0225] The water levels of #5 and 6 low-pressure heaters are both stable at -230 mm (±50) and maintained for 3 min.

[0226] Step 7

[0227] Action: Turn on the automatic control of the accident drain regulating valves of #5 and #6 low-pressure heaters, and set the set values of the accident drain regulating valves of #5 and #6 low-pressure heaters to 50 mm at a rate of 50 mm / min.

[0228] Feedback (AND):

[0229] The accident drain regulating valves of #5 and #6 low-pressure heaters are both in the automatic position;

[0230] The valve positions of the accident drain regulating valves of #5 and #6 low-pressure heaters are both < 5%.

[0231] Step 8

[0232] Action: Set the set value of the normal drain regulating valve of #5 low-pressure heater to -50 mm at a rate of 20 mm / min

[0233] Feedback (AND):

[0234] The normal drain regulating valve of #5 low-pressure heater is in the automatic position;

[0235] The water level of #5 low-pressure heater is stable at -50 mm (±50) and maintained for 3 min.

[0236] Step 9

[0237] Action: Set the set value of the normal drain regulating valve of #6 low-pressure heater to -50 mm at a rate of 20 mm / min

[0238] Feedback (AND):

[0239] The normal drain regulating valve of #6 low-pressure heater is in the automatic position;

[0240] The water level of #6 low-pressure heater is stable at -50 mm (±50) and maintained for 3 min.

[0241] In an embodiment of the present invention, the #7 and #8 low-pressure heaters are automatically put into operation: through step-by-step control, input / output condition judgment, equipment control and feedback, it is ensured that the equipment can be put into operation smoothly and step by step. Each step adjusts the operation according to the equipment status and real-time parameters to avoid overshoot and ensure normal automatic regulation. As Figure 7 shown.

[0242] Figure 7 : The #7 and #8 low-pressure heaters are put into program control, and the specific logic is as follows:

[0243] Start permission (AND):

[0244] The steam turbine is at a constant speed of 2000 ± 10 rpm;

[0245] The extraction steam of the fifth and sixth stages is not put into operation;

[0246] The vacuum of the condenser < -75 kPa;

[0247] #7 and 8 Low-pressure Feedwater Side Has Been Put into Operation (#7A and 8A Low-pressure Feedwater Side Inlet Motorized Valves Are Open and Outlet Motorized Valves Are Open, #7B and 8B Low-pressure Feedwater Side Inlet Motorized Valves Are Open and Outlet Motorized Valves Are Open, Bypass Motorized Valve Is Closed).

[0248] Step 1

[0249] Action: Fully open the emergency drain regulating valves of #7A, 7B, 8A, and 8B low-pressure heaters;

[0250] Fully close the normal drain regulating valves of #7A, 7B, 8A, and 8B low-pressure heaters;

[0251] Feedback (AND):

[0252] The valve positions of the emergency drain regulating valves of #7A, 7B, 8A, and 8B low-pressure heaters are all > 95%;

[0253] The valve positions of the normal drain regulating valves of #7A, 7B, 8A, and 8B low-pressure heaters are all < 5%.

[0254] Step 2

[0255] Action: Put the emergency drain and normal drain regulating valves of #7A and 7B low-pressure heaters into automatic;

[0256] Set the set value of the emergency drain regulating valve of #7A and 7B low-pressure heaters to 50 mm at a rate of 20 mm / min;

[0257] Set the set value of the normal drain regulating valve of #7A and 7B low-pressure heaters to -50 mm at a rate of 20 mm / min.

[0258] Feedback (OR):

[0259] The water level of #7A low-pressure heater is stable (AND):

[0260] The normal drain valve of #7A low-pressure heater is in the automatic position;

[0261] The liquid level of #7A low-pressure heater is stable at -50 mm for 3 min;

[0262] The emergency drain valve of #7A low-pressure heater is in the automatic position;

[0263] The valve position of the emergency drain valve of #7A low-pressure heater is less than 5%.

[0264] The water level of #7B low-pressure heater is stable (AND):

[0265] The normal drain valve of #7B low-pressure heater is in the automatic position;

[0266] The liquid level of #7B low-pressure heater is stable at -50 mm for 3 min;

[0267] The emergency drain valve of #7B low-pressure heater is in the automatic position;

[0268] The valve position of the accident drain valve of the #7B low-pressure heater is less than 5%.

[0269] Step 3

[0270] Action: Put the automatic control of the accident drain valves and normal drain valves of the #8A and 8B low-pressure heaters into operation;

[0271] Set the set values of the accident drain valves of the #8A and 8B low-pressure heaters to 50 mm at a rate of 20 mm / min;

[0272] Set the set values of the normal drain valves of the #8A and 8B low-pressure heaters to -50 mm at a rate of 20 mm / min.

[0273] Feedback (or):

[0274] The water level of the #8A low-pressure heater is stable (and):

[0275] The normal drain valve of the #8A low-pressure heater is in the automatic position;

[0276] The liquid level of the #8A low-pressure heater is stable at -50 mm for 3 min;

[0277] The accident drain valve of the #8A low-pressure heater is in the automatic position;

[0278] The valve position of the accident drain valve of the #8A low-pressure heater is less than 5%.

[0279] The water level of the #8B low-pressure heater is stable (and):

[0280] The normal drain valve of the #8B low-pressure heater is in the automatic position;

[0281] The liquid level of the #8B low-pressure heater is stable at -50 mm for 3 min;

[0282] The accident drain valve of the #8B low-pressure heater is in the automatic position;

[0283] The valve position of the accident drain valve of the #8B low-pressure heater is less than 5%.

[0284] According to the high- and low-pressure heater automatic switching management system of a thermal power plant according to an embodiment of the present invention, the high- and low-pressure heater switching program control, status monitoring, and multi-mode switching of a thermal power plant can be realized on a DCS system, achieving precise control and automatic adjustment during the automatic execution process, and finally ensuring that the unit always operates smoothly and orderly.

[0285] To implement the above embodiment, a high- and low-pressure heater automatic switching management method for a thermal power plant is further provided in this embodiment, including:

[0286] According to the set requirements, collect the status information during the start-up and shutdown processes of the unit and the real-time measurement data of the high- and low-pressure heater systems, and automatically judge the initial states of the high- and low-pressure heaters;

[0287] According to the preset control boundary parameters and the connection / disconnection processes, start and execute as required, and judge the connection / disconnection timing of the high- and low-pressure heaters according to the preset connection / disconnection control conditions, and automatically control the opening and closing of the execution valves and the linkage of the equipment;

[0288] The operating parameters of the high- and low-pressure heaters are collected in real time through the parameter monitoring module, so as to monitor the state of the equipment during the connection / disconnection process and adjust the operation process according to the monitoring data;

[0289] During the operation of the unit, the high- and low-pressure heaters are automatically disconnected to create conditions for dealing with heater-related defects, and the heaters are automatically reconnected after troubleshooting; and,

[0290] Online optimize the control logic and modify the control parameters.

[0291] According to the automatic connection / disconnection management method of the high- and low-pressure heaters in a thermal power plant according to an embodiment of the present invention, the programmed control, status monitoring and multi-mode switching of the connection / disconnection of the high- and low-pressure heaters in a thermal power plant can be realized on a DCS system, achieving precise control and automatic adjustment during the automatic execution process, and finally ensuring that the unit always operates smoothly and orderly.

[0292] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0293] In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present invention, "a plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

Claims

1. An automatic switching management system for high and low pressure heaters in a thermal power plant, characterized in that, Including: A measuring point data acquisition module, which is used to automatically collect the status information during the start-up and shutdown processes of the unit and the real-time measuring point data of the high- and low-pressure heater systems based on the DCS system, and automatically judge the initial states of the high- and low-pressure heaters according to the set requirements; A control module, which is used to start execution as required based on the preset control boundary parameters and the put-in and withdrawal processes after the automatic put-in and withdrawal management system is started; An equipment control module, which is used to judge the put-in and withdrawal timing of the high- and low-pressure heaters according to the preset put-in and withdrawal control conditions, and automatically control the opening and closing of the execution valves and the equipment linkage; A parameter monitoring module, which is used to collect the operation parameters of the high- and low-pressure heaters in real time, monitor the status of the equipment during the put-in and withdrawal processes, and adjust the operation process according to the monitoring data; An automatic put-in and withdrawal module, which is used to automatically withdraw the high- and low-pressure heaters during the operation of the unit, create conditions for dealing with heater-related defects, and automatically reinvest the heaters after troubleshooting; An optimization control module, which is used to optimize the control logic online and modify the control parameters.

2. The system according to claim 1, wherein The method further includes: Initializing the automatic put-in and withdrawal operation interface module of the high- and low-pressure heaters in the thermal power plant; Performing automatic and manual mode switching, and dynamically adjusting the control mode according to user input or system requirements; Updating and displaying the indicator lights or labels by reading the equipment status information to reflect the current working status of the equipment; Executing each step in the preset process, and processing the step sequence and skip function as needed, allowing specific steps to be skipped or the next step to be continued in a multi-step automation task; Providing a time parameter setting interface for timing operations or recording the process duration to ensure that the operations meet the predetermined time requirements; Monitoring and responding to the input of the general operation buttons to directly control the start-up, shutdown, and reset of the equipment.

3. The system according to claim 2, characterized in that, Automatically judging by logic whether the high-pressure heater is ready for investment.

4. The system according to claim 3, characterized in that Controlling and automatically adjusting the automatic investment of the high-pressure heater through multi-step control, condition judgment, input-output status association, and global label management.

5. The system according to claim 4, characterized in that, Automatically judging by logic whether the high-pressure heater is allowed to withdraw, including an automatic adjustment and safety monitoring mechanism to ensure that no adverse consequences will occur when the high-pressure heater is automatically withdrawn.

6. The system according to claim 5, wherein Automatically investing the equipment through step-by-step control, condition judgment, time delay, and status feedback.

7. The system according to claim 5, wherein Ensuring the smooth and step-by-step investment operation of the equipment through step-by-step control, input-output condition judgment, equipment control, and feedback; each step adjusts the operation according to the equipment status and real-time parameters.

8. An automatic switching management method for high and low pressure heaters in a thermal power plant, characterized in that, Including: Collecting the status information during the start-up and shutdown processes of the unit and the real-time measuring point data of the high- and low-pressure heater systems according to the set requirements, and automatically judging the initial states of the high- and low-pressure heaters; Starting execution as required based on the preset control boundary parameters and the put-in and withdrawal processes, and judging the put-in and withdrawal timing of the high- and low-pressure heaters according to the preset put-in and withdrawal control conditions, and automatically controlling the opening and closing of the execution valves and the equipment linkage; Collecting the operation parameters of the high- and low-pressure heaters in real time through the parameter monitoring module, monitoring the status of the equipment during the put-in and withdrawal processes, and adjusting the operation process according to the monitoring data; Automatically withdraw the high- and low-pressure heaters during the operation of the unit to create conditions for dealing with defects related to the heaters, and automatically re-insert the heaters after troubleshooting; and, Online optimize the control logic and modify the control parameters.

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