A method and device for full-process control of boiler feedwater based on automatic start-stop control.

Abstract

This invention discloses a method for full-process control of boiler feedwater based on automatic start-stop control, including: real-time monitoring of the condenser hot well liquid level; during the condenser hot well water replenishment process, when it is confirmed that the opening degree of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position, and the liquid level in the condensate storage tank is greater than or equal to the first monitored liquid level, controlling the opening of the condenser water supply bypass electric valve. This solution can accurately control the condenser water supply bypass electric valve; and optimize the start-stop control and opening / stop interlocking logic of the condenser hot well water supply side equipment.

Description

Technical Field

[0001] This invention relates to the field of boiler control technology, and in particular to a method and device for full-process control of boiler feedwater based on automatic start-stop control, a storage medium, and an electronic device. Background Technology

[0002] In related fields, gas turbines and their combined cycle units have seen rapid development due to their advantages such as high efficiency, low emissions, flexible start-up and shutdown, and good peak-shaving performance. Meanwhile, they primarily function as peak-shaving units in the power grid structure, experiencing very frequent daytime start-ups and nighttime shutdowns. To adapt to the needs of frequent start-ups and shutdowns, rapid start-ups, and timely peak-shaving of gas-steam combined cycle units, the implementation of Automatic Plant Start-up and Shutdown Systems (APS) has become an inevitable trend.

[0003] To expedite start-up and shorten unit start-up time, a multi-path parallel approach is typically used during the waste heat boiler water supply phase in APS design and implementation. While this control method speeds up the water supply process, the close interrelationships and mutual constraints among the boiler feedwater systems can easily lead to supply-feedwater mismatch. On one hand, excessively rapid low-pressure drum water supply may result in untimely condenser hot well water supply, triggering low-limit protection for condensate recirculation flow and causing simultaneous startup of the condensate pumps, resulting in dual-unit operation. On the other hand, untimely low-pressure boiler water supply due to high- and medium-pressure drum water supply can lead to a large deviation between the actual low-pressure drum water level and the target setpoint, causing the regulating valve to trip manually. Furthermore, most power plants currently suffer from internal leakage in their water supply regulating valves due to equipment aging. During the unit's heating and pressurization phase, when the steam flow in the steam drum is low, the internal leakage flow after the water supply regulating valve is fully closed is sufficient to maintain the steam drum liquid level at the target level, and the steam drum liquid level may even rise slowly. When the actual steam drum liquid level exceeds a certain value, it will trigger the regulating valve to trip manually. Meanwhile, the automatic control of waste heat boiler feedwater is mostly effective only when the unit load is stable. However, during start-up and shutdown, especially during boiler expansion and pressurization, rapid load changes, and unit disconnection and reconnection, the small size of the waste heat boiler steam drum makes it prone to false water levels, resulting in less than ideal automatic control and reliance on manual operation. Moreover, the target value for steam drum liquid level control varies at different stages.

[0004] Therefore, how to achieve full-process automatic control of boiler feedwater from boiler water replenishment to full-load operation of the unit is the key to the successful implementation of APS. At the same time, it is of great significance to reduce the labor intensity of operators and improve the automation level of the unit. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention aims to provide a method, apparatus, storage medium, and electronic device for full-process boiler feedwater control based on self-start-stop control, thereby at least resolving the issue of poor unit feedwater control performance in the prior art.

[0006] The technical solution of this invention is implemented as follows:

[0007] This invention provides a method for full-process control of boiler feedwater based on automatic start-stop control, comprising:

[0008] Real-time monitoring of the liquid level in the condenser hot well;

[0009] During the condenser hot well water replenishment process, when it is confirmed that the opening of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position, and the liquid level of the condensate storage tank is greater than or equal to the first monitored liquid level, the condenser water supply bypass electric valve is controlled to open.

[0010] Furthermore, embodiments of the present invention provide a boiler feedwater end-to-end control system based on automatic start-stop control, comprising:

[0011] The condenser hot well liquid level monitoring module is used for real-time monitoring of the condenser hot well liquid level.

[0012] The condenser water supply bypass electric valve control module is used to control the condenser water supply bypass electric valve to open during the condenser hot well water replenishment process, when it is confirmed that the opening degree of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position, and the liquid level of the condensate storage tank is greater than or equal to the first monitored liquid level.

[0013] Furthermore, embodiments of the present invention provide a storage medium storing a computer program thereon, wherein when the program is executed by a processor, it implements the boiler feedwater full-process control method based on self-start-stop control as described in the above embodiments.

[0014] Furthermore, embodiments of the present invention provide an electronic device, including: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to execute the boiler feedwater full-process control method based on self-start-stop control as described in the above embodiments by executing the executable instructions.

[0015] This invention provides a method for full-process control of boiler feedwater based on automatic start-stop control. By monitoring the liquid level of the condenser hot well in real time, the method can make judgments based on the current liquid level of the condenser hot well, the opening degree of the condenser water level regulating valve, and the current liquid level of the condensate storage tank, thereby accurately controlling the electric valve of the condenser water supply bypass; and optimizing the start-stop control and opening / stop interlocking logic of the equipment on the water supply side of the condenser hot well. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of a low-pressure water supply system provided in an embodiment of the present invention;

[0018] Figure 2 A schematic diagram of a boiler feedwater control method based on automatic start-stop control provided in an embodiment of the present invention;

[0019] Figure 3 A schematic diagram of a boiler feedwater control system based on self-start-stop control provided in an embodiment of the present invention;

[0020] Figure 4 A schematic diagram of a storage medium provided in an embodiment of the present invention;

[0021] Figure 5 This is a schematic diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0023] This invention provides a method for full-process control of boiler feedwater based on automatic start-stop control, which can be applied to... Figure 1 The low-pressure water supply system shown is for reference. Figure 1As shown, the low-pressure water supply system includes: a condensate storage tank makeup electric valve 101, which is connected upstream to the makeup water source and downstream to the inlet of the condensate storage tank 102; the outlet of the condensate storage tank 102 is connected to the condensate transfer pump 103 and the bypass manual valve 104 respectively; the condensate transfer pump 103 and the bypass manual valve 104 are connected in parallel, and their outlets are connected to the inlet of the condenser water level regulating valve 106 and the inlet of the condenser water supply bypass circuit valve 105 respectively; the outlets of the condenser water level regulating valve 106 and the condenser water supply bypass circuit valve 105 are connected to the inlet of the condenser hot well 107 respectively; the condenser water level regulating valve 106 and the condenser water supply bypass circuit valve 105 are connected in parallel. The outlet of the condenser hot well 107 is connected to the low-pressure steam drum 111 via a condensate pump 109 and a low-pressure steam drum level regulating valve 110. A condensate recirculation flow regulating valve 108 is installed between the low-pressure steam drum level regulating valve 110 and the circulating water inlet of the condenser hot well 107. The outlet of the low-pressure steam drum 111 is connected to the medium-pressure steam drum 112 via a medium-pressure feedwater pump 115 and a medium-pressure steam drum level regulating valve 116. The outlet of the low-pressure steam drum 111 is connected to the high-pressure steam drum 113 via a high-pressure feedwater pump 117 and a high-pressure steam drum level regulating valve 118. The system also includes a waste heat boiler 114. The components of the low-pressure feedwater system can be referenced from existing technologies.

[0024] Figure 2 This is a flowchart illustrating a boiler feedwater control method based on automatic start-stop control, provided by an embodiment of the present invention; as shown below. Figure 2 As shown in the embodiments of this application, the boiler feedwater control method based on automatic start-stop control includes:

[0025] Step S11: Real-time monitoring of the condenser hot well liquid level;

[0026] Step S12: During the condenser hot well water replenishment process, when it is confirmed that the opening of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position, and the liquid level of the condensate storage tank is greater than or equal to the first monitored liquid level, the condenser water supply bypass electric valve is controlled to open.

[0027] In this embodiment, level sensors can be installed in the condenser hot well and condensate storage tank to collect real-time liquid level data and transmit it to the back-end control terminal wirelessly or via wired connection. The back-end control terminal can execute the logic of the aforementioned boiler feedwater control method based on automatic start-stop control, receive parameters collected by each sensor, send control commands to each solenoid valve, and receive response information from each valve. For example, the back-end control terminal can be a server or a computer or other hardware device.

[0028] Specifically, to ensure that the condenser hot well can supply water in a timely manner and have a sufficient water source during the water replenishment process of the high, medium and low pressure steam drums of the waste heat boiler, the control logic of the condenser hot well water supply system equipment is optimized, mainly including the condensate storage tank water replenishment electric valve, the condensate transfer pump and the condenser water supply bypass electric valve.

[0029] Optionally, in this embodiment of the application, when the opening of the condenser water level regulating valve is less than or equal to the second preset condenser water level regulating valve position, the condenser water bypass electric valve is controlled to close.

[0030] Specifically, for the condenser water bypass electric valve, the control logic can be as follows: when the condenser water level regulating valve is in the automatic position; the condenser water level regulating valve position feedback is ≥80%; and the condensate storage tank level is ≥50%*H, the background control terminal sends a control signal to the condenser water bypass electric valve based on the real-time collected information, so that it opens automatically.

[0031] In addition, when the condenser water level regulating valve is in the automatic position and the valve position feedback is ≤20%, the background control terminal sends a control signal to the condenser water bypass electric valve based on the real-time collected information, so that it automatically closes.

[0032] No restrictions are set on the opening and closing conditions for the condenser water bypass electric valve.

[0033] Optionally, in this embodiment of the application, when it is detected that the condenser water bypass electric valve is fully open, the opening degree of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position, and the liquid level of the condenser hot well is lower than the target liquid level of the condenser hot well, the current liquid level of the condensate storage tank is obtained.

[0034] If the current liquid level in the condensate storage tank meets the preset start-up conditions, the condensate delivery pump is controlled to start.

[0035] Optionally, in this embodiment of the application, when the liquid level of the condenser hot well is monitored to be higher than or equal to the target liquid level of the condenser hot well, and the opening of the condenser water level regulating valve is less than or equal to the valve position of the second preset condenser water level regulating valve, the condensate delivery pump is controlled to be shut down.

[0036] Specifically, for the condensate transfer pump, considering the unit's energy-saving effect, if the condenser hot well water level is still lower than the target level when the condenser water bypass electric valve is fully open and the condenser water regulating valve is already in a large position, the condensate transfer pump will be started to accelerate water replenishment. The condensate transfer pump will be shut down when the water level reaches the target level and the condenser water level regulating valve has a large adjustment margin.

[0037] Specifically, its control logic may include: the condenser water bypass electric valve is fully open; the condenser water level regulating valve is in the automatic position; the condenser water level regulating valve position feedback is ≥80%; and the condenser hot well liquid level is ≤LTCon_SP-△L. Alternatively, the condenser hot well liquid level is ≥LTCon_SP-△L; the condenser water level regulating valve is in the automatic position; and the condenser water level regulating valve position feedback is ≤55%. Where LTCon_SP is the target liquid level value of the condenser hot well, and △L is the target liquid level margin of the condenser hot well, typically taken to be between 5%*LTCon_SP and 10%*LTCon_SP.

[0038] Optionally, in this embodiment of the application, for the condensate transfer pump, the starting condition for the condensate transfer pump can be set to a condensate storage tank level greater than 25%*H, and the shutdown condition for the condensate transfer pump is not set.

[0039] Optionally, in this embodiment of the application, the liquid level of the condensate storage tank is monitored;

[0040] During the water replenishment process, when the current liquid level of the condensate storage tank is detected to be lower than or equal to the monitored liquid level of the first condensate storage tank, the electric valve for replenishing the condensate storage tank is opened; and

[0041] When the current liquid level of the condensate storage tank is detected to be higher than or equal to the monitored liquid level of the second condensate storage tank, the electric valve for replenishing water in the condensate storage tank is controlled to close.

[0042] Specifically, during the water replenishment phase, the condensate tank level is maintained at a high level, and the interlocking switch logic of the condensate tank water replenishment electric valve is optimized to ensure a sufficient water supply to the condenser hot well. The control logic may include: automatically opening the condensate tank water replenishment electric valve when the condensate tank level is ≤70%*H based on monitoring data; or automatically closing the condensate tank water replenishment electric valve when the condensate tank level is ≥90%*H. Here, H is the full-scale condensate tank level, and the level setpoint of the condensate tank water replenishment electric valve interlocking switch is restored to the original setpoint after water replenishment is completed and the gas turbine is ignited.

[0043] For the electric valve for replenishing condensate storage tanks, no restrictions on opening or closing conditions are required.

[0044] Optionally, in this embodiment of the application, the method further includes: obtaining the current liquid level deviation of the condenser hot well between the current liquid level of the condenser hot well and the corresponding target monitoring liquid level of the condenser hot well;

[0045] Adjust the opening of the low-pressure steam drum water level regulating valve according to the current liquid level deviation of the condenser hot well.

[0046] Specifically, when the condenser water level drops too low and continues to fall due to untimely water replenishment during the low-pressure steam drum water replenishment process, the opening of the low-pressure regulating valve is limited based on the deviation between the real-time liquid level of the condenser hot well and the target value. This is to slow down the water replenishment rate of the low-pressure steam drum and prevent excessive water replenishment from the low-pressure and medium-pressure steam drums, which could lead to an excessively low condenser liquid level and further trigger the low limit value of the condensate recirculation flow, thus starting both condensate pumps.

[0047] The opening limit function for the low-pressure water supply regulating valve is:

[0048]

[0049] Wherein, the input variable x is the deviation between the real-time liquid level of the condenser hot well and the target value; specifically,

[0050] x = LTCon_SEL - LTCon_SP

[0051] Wherein, LTCon_SEL is the real-time liquid level of the condenser hot well; LTCon_SP is the target set value of the liquid level of the condenser hot well.

[0052] Correspondingly, the final output of the low-pressure steam drum water supply regulating valve opening command is:

[0053] F2(x)=MIN[F11(x),LCVLP_OP]

[0054] Where F2(x) is the final output value of the low-pressure water supply regulating valve opening command after the opening limit; F1(x) is the low-pressure water supply regulating valve opening limit function; LCVLP_OP is the low-pressure water supply regulating valve opening command without the opening limit; MIN[] is the minimum value function.

[0055] Preferably, in some exemplary embodiments, F1(x) = [-95mm, -5%; -90mm, 0%; -70mm, 3%; -50mm, 7%; -30mm, 15%; -20mm, 100%].

[0056] Optionally, in this embodiment of the application, the method further includes: real-time monitoring of the liquid level in the low-pressure steam drum;

[0057] Obtain the current liquid level deviation of the low-pressure steam drum between the current liquid level of the low-pressure steam drum and the corresponding target liquid level of the low-pressure steam drum;

[0058] Adjust the opening degree of the medium-pressure steam drum water level regulating valve and / or the high-pressure steam drum water level regulating valve according to the current liquid level deviation of the low-pressure steam drum.

[0059] Specifically, logic can be set to limit the opening of the high- and medium-pressure steam drum water supply regulating valves. When the low-pressure steam drum is not replenished in time during the simultaneous replenishment of water to both the high- and medium-pressure steam drums, resulting in a low and continuously decreasing low-pressure steam drum level, the opening of the high- and medium-pressure water supply regulating valves can be limited based on the deviation between the real-time low-pressure steam drum level and the target value. This slows down the water replenishment rate of the high- and medium-pressure steam drums, preventing a continuous drop in the low-pressure drum level due to excessive water replenishment from the high- and medium-pressure steam drums, which could trigger the regulating valves to trip manually.

[0060] Specifically, the opening limit function of the high and medium pressure water supply regulating valve can include:

[0061]

[0062] Wherein, the input variable x is the deviation between the real-time liquid level of the low-pressure steam drum and the target setpoint. X = LTLP_SEL - LTLP_SP; where LTLP_SEL is the real-time liquid level of the low-pressure steam drum; and LTLP_SP is the target setpoint for the liquid level of the low-pressure steam drum.

[0063] The final outputs of the opening commands for the high and medium pressure water supply regulating valves are as follows:

[0064] F4(x) = MIN[F3(x), LCVHP_OP]

[0065] F5(x) = MIN[F3(x), LCVIP_OP]

[0066] Wherein, F4(x) is the final output value of the opening command of the high-pressure water supply regulating valve after the opening limit; F5(x) is the final output value of the opening command of the medium-pressure water supply regulating valve after the opening limit; F3(x) is the opening limit function of the high and medium pressure water supply regulating valves; LCVHP_OP is the opening command of the high-pressure water supply regulating valve without the opening limit; LCVIP_OP is the opening command of the medium-pressure water supply regulating valve without the opening limit; MIN[] is the function to take the minimum value.

[0067] Preferably, in some exemplary embodiments, F2(x) = [-155mm, -5%; -150mm, 0%; -120mm, 3%; -90mm, 8%; -60mm, 14.5%; -30mm, 20%; -25mm, 100%].

[0068] Optionally, in this embodiment of the application, the method further includes: when the current liquid level deviation of the low-pressure steam drum is less than or equal to the first deviation monitoring value, and the unit is in the first target operation stage, the high and medium pressure steam drums are in the water replenishment process, the water supply regulating valve of the low-pressure steam drum is in manual control state, and the current liquid level deviation between the current liquid level of the condenser hot well and the target liquid level of the condenser hot well is greater than or equal to the second deviation monitoring value, controlling the low-pressure steam drum water level regulating valve to a specified opening degree.

[0069] Specifically, during the simultaneous replenishment of water to the condenser hot well and the high- and medium-pressure boiler drums, if the water supply to the low-pressure boiler drum exceeds the replenishment amount, the low-pressure boiler drum will not be replenished in time. This causes the low-pressure boiler drum level to drop continuously. When the deviation between the real-time level and the target value becomes too large, the regulating valve will trip manually, and water will be replenished to the low-pressure boiler drum at a smaller, fixed opening. As water is continuously replenished to the condenser hot well, once the condenser level is replenished to near the target setpoint and the deviation between the actual low-pressure boiler drum level and the initial target level is insufficient to trigger the regulating valve to trip manually, the low-pressure boiler drum water supply regulating valve will automatically reactivate, with the setpoint being the initial target level.

[0070] Specifically, for the automatic control logic of the low-pressure boiler drum water supply regulating valve, the following allowable conditions can be preset: the deviation between the real-time liquid level of the low-pressure boiler drum and the target setpoint ≤ K1, i.e., ABS(LTLP_SEL-LTLP_SP)≤K1. This control logic can include: the unit is in the water supply stage (or before gas turbine ignition); the high- and intermediate-pressure boiler drums are being replenished with water; the low-pressure boiler drum water supply regulating valve is in manual mode; the deviation between the real-time liquid level of the condenser hot well and the target setpoint ≥ LTCon_SP-△L, i.e., ABS(LTCon_SEL-LTCon_SP)≥LTCon_SP-△L. Where LTLP_SEL is the real-time liquid level of the low-pressure steam drum; LTLP_SP is the target setpoint for the low-pressure steam drum liquid level; LTCon_SEL is the real-time liquid level of the condenser hot well; LTCon_SP is the target setpoint for the condenser hot well liquid level; and △L is the target liquid level margin of the condenser hot well.

[0071] Optionally, in this embodiment of the application, the method further includes: real-time monitoring of the liquid level in the high-pressure steam drum;

[0072] When the current liquid level in the high-pressure steam drum exceeds the preset first monitoring liquid level of the high-pressure steam drum, the high-pressure steam drum water level regulating valve is closed and switched to manual control mode; and

[0073] Control the high-pressure steam drum to drain to the second monitoring level of the high-pressure steam drum;

[0074] The operating status of the high-pressure steam drum water level regulating valve is controlled according to the current liquid level of the high-pressure steam drum.

[0075] Specifically, this may also include the automatic control logic for the pressure boiler drum water supply regulating valve. During the unit's heating and pressurization phase, when the steam flow in the boiler drum is relatively low, the internal leakage flow after the pressure boiler drum water supply regulating valve is fully closed can meet the requirement that the boiler drum liquid level is at the normal level, and the boiler drum liquid level may even rise slowly. If the actual value of the boiler drum liquid level exceeds a certain value (K2), the regulating valve will be triggered to trip manually.

[0076] For example, for the 9FA gas turbine, K2 = 50mm, that is, when the pressure cooker drum liquid level exceeds 50mm, the pressure cooker drum water regulating valve quick-closing function is triggered and jumps to the manual position.

[0077] When the following conditions are met simultaneously, the system is marked as A and the signal is held, while the target liquid level setpoint LT_HP of the pressure boiler drum at this time is recorded. The conditions may include:

[0078] (1) The liquid level in the pressure cooker drum is greater than 50 mm;

[0079] (2) The water inlet regulating valve of the pressure cooker drum is in the automatic position, with a 2-second delay on the falling edge;

[0080] (3) The water regulating valve of the pressure cooker drum is in the manual position.

[0081] If A = true, open the pressure cooker drum drain valve to drain the pressure cooker drum until the actual liquid level in the pressure cooker drum is ≤10mm and ≤LT_HP + △HT. Then, activate the automatic high-pressure water supply regulating valve, with the set value being LT_HP. △HT represents the actual liquid level margin in the pressure cooker drum.

[0082] Preferably, in some exemplary embodiments, △HT∈(10mm, 15mm).

[0083] Optionally, in this embodiment of the application, the method further includes: real-time monitoring of the current liquid level of each steam drum; and adaptive control of the opening degree of the water supply regulating valve corresponding to each steam drum based on the liquid level deviation between the current liquid level of the steam drum and the corresponding preset liquid level of the steam drum.

[0084] Specifically, the aforementioned steam drum can be a low-pressure, medium-pressure, or high-pressure steam drum. It may also include control logic for adaptive adjustment of the boiler drum liquid level target value. The target value for boiler drum liquid level control varies at different stages from boiler feedwater to full-load operation. Typically, during the feedwater process for high, medium, and low-pressure boiler drums, the target setpoint is the starting water level (lower than the normal water level setpoint) to ensure that after unit ignition, the boiler water expands due to temperature and pressure increases, and the water level rises due to thermal expansion, the liquid level does not become too high, affecting normal unit operation. After the boiler water expansion is complete, the target liquid level setpoint for the boiler drum is switched from the starting water level setpoint to the normal water level setpoint.

[0085] The sampling points for water expansion in the waste heat boiler are taken from the pressure measurement points of the boiler drum. That is, the pressure values ​​of the corresponding boiler drum pressure are selected from the sampling points for water expansion in different boiler drums.

[0086] The condition for determining the end of boiler water expansion is:

[0087] (1) After the boiler drum pressure is optimized, it is ≥PT1 and the boiler drum pressure rises by 0.3MPa after the gas turbine is ignited;

[0088] (2) After the boiler drum is optimized and the pressure is ≥PT2, wait 10 minutes after the gas turbine is ignited;

[0089] If any of the above conditions are met, it indicates that the boiler water expansion has ended.

[0090] Preferably, in some exemplary embodiments, PT1∈(1.5,2) and PT2∈(3,4). The specific parameters need to be adjusted according to different controlled objects.

[0091] After the boiler water expansion is complete, the target liquid level setting of the boiler drum will be switched from the start-up water level setting to the normal water level setting.

[0092] Optionally, in this embodiment of the application, the method further includes: identifying the current operating stage of the unit, and configuring the preset liquid level of each steam drum corresponding to the current operating stage of the unit.

[0093] Specifically, a feedforward adaptive control function can also be configured for the control strategy. In most cases, automatic control of waste heat boiler feedwater is only effective when the unit load is stable. However, during start-up and shutdown, especially during boiler expansion and pressurization, rapid load changes, and unit decoupling / reconnection, the small size of the waste heat boiler drum makes it prone to false water levels, resulting in less than ideal automatic control performance, and manual operation remains the primary method. To improve the unit's adjustment and control capabilities under special conditions such as rapid load changes and unit decoupling / reconnection, this scheme adds a feedforward adaptive control function to the original control strategy to ensure that the boiler drum water level is controlled within the normal range, guaranteeing the safe and stable operation of the unit. Specifically, the deviation between the actual water level in the steam drum and the target setpoint is used as the input variable for the feedforward adaptive function.

[0094] FF = -K3*ΔLT*F6(x)

[0095] ΔLT=LT_SEL-LT_SP

[0096] Where F6(x) is a section inertia function Right now,

[0097]

[0098] After amplitude limitation, the feedforward adaptive function outputs F7(x) = Med[15, FF, -15], where Med[] is the intermediate value function; where LT_SEL is the real-time liquid level of the steam drum; LT_SP is the target setpoint of the steam drum liquid level; ΔLT is the deviation between the real-time liquid level of the steam drum and the target setpoint; K is the opening coefficient of the water supply regulating valve; T is the first-order inertial time constant; K3 is the reciprocal of the manual setpoint for the large jump in the deviation between the real-time liquid level of the steam drum and the target setpoint.

[0099] Preferably, in some exemplary embodiments, K∈(20, 25), K3∈(0.9, 0.12), and T∈(5, 10). Specific parameters can be adjusted according to different controlled objects.

[0100] In this embodiment, the method optimizes the start-up, shutdown, and interlocking logic of the condenser hot well water supply side equipment. By setting a valve opening limit function for the low-pressure water supply regulating valve (slowing down the water supply rate to the low-pressure boiler drum when the condenser level continuously decreases), it prevents the condenser level from becoming too low during boiler drum makeup, thus avoiding triggering the low limit value for condensate recirculation flow and activating both condensate pumps. By setting an opening limit function for the high- and medium-pressure water supply regulating valve (slowing down the water supply rate to the high- and medium-pressure boiler drums when the low-pressure boiler drum level continuously decreases), it prevents the low-pressure drum level from continuously decreasing due to large amounts of water supply to the high- and medium-pressure boiler drums, thus triggering the regulating valve to switch to manual mode. By setting an automatic activation function for the boiler drum water supply regulating valve, after the actual boiler drum level deviates too much from the target value and switches to manual mode, it automatically re-activates to automatic mode once the automatic activation conditions are met. By setting an adaptive adjustment function for the boiler level target value, it ensures that the boiler drum level is controlled at the optimal position at different stages from boiler makeup to full-load operation. By implementing feedforward adaptive control, the unit's adjustment and control capabilities are improved under special operating conditions such as rapid load changes and unit decoupling, ensuring that the boiler drum water level is maintained within the normal range. This solution enables fully automated boiler feedwater control for gas turbine combined cycle units from boiler feedwater intake to full-load operation, reducing the workload of operators, improving the unit's automation level and the power plant's competitiveness, and laying the foundation for the successful implementation of the unit's Advanced Power System (APS).

[0101] Furthermore, embodiments of the present invention provide a boiler feedwater end-to-end control system based on automatic start-stop control. Figure 3 A schematic diagram of a boiler feedwater control system based on automatic start-stop control is provided as an embodiment of the present invention; as shown. Figure 3 As shown in the embodiment of this application, the boiler feedwater control system 20 based on automatic start-stop control includes:

[0102] The condenser hot well liquid level monitoring module 201 is used for real-time monitoring of the condenser hot well liquid level.

[0103] The condenser water supply bypass electric valve control module 202 is used to control the condenser water supply bypass electric valve to open during the condenser hot well water replenishment process, when it is confirmed that the opening degree of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position and the liquid level of the condensate storage tank is greater than or equal to the first monitored liquid level.

[0104] Optionally, the condenser water bypass electric valve control module 202 can also be used to control the condenser water bypass electric valve to close when the opening of the condenser water level regulating valve is less than or equal to the second preset condenser water level regulating valve position.

[0105] Optionally, the system further includes: a condensate transfer pump control module, used to acquire the current liquid level of the condensate storage tank when the monitoring shows that the condenser water bypass electric valve is fully open, the opening degree of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position, and the liquid level of the condenser hot well is lower than the target liquid level of the condenser hot well; and if the current liquid level of the condensate storage tank meets the preset start-up conditions, control the condensate transfer pump to start.

[0106] Optionally, the condensate delivery pump control module can also be used to control the condensate delivery pump to shut down when the condenser hot well liquid level is higher than or equal to the condenser hot well target liquid level and the opening of the condenser water level regulating valve is less than or equal to the second preset condenser water level regulating valve position.

[0107] Optionally, the system further includes a condensate storage tank level monitoring module for monitoring the level of the condensate storage tank.

[0108] The condensate storage tank water replenishment electric valve control module is used to control the condensate storage tank water replenishment electric valve to open when the current liquid level of the condensate storage tank is lower than or equal to the monitoring liquid level of the first condensate storage tank during the water replenishment process; and to control the condensate storage tank water replenishment electric valve to close when the current liquid level of the condensate storage tank is higher than or equal to the monitoring liquid level of the second condensate storage tank.

[0109] Optionally, the system further includes: a low-pressure steam drum water level regulating valve opening management module, used to obtain the current liquid level deviation of the condenser hot well between the current liquid level of the condenser hot well and the corresponding target monitoring liquid level of the condenser hot well; and to adjust the opening of the low-pressure steam drum water level regulating valve according to the current liquid level deviation of the condenser hot well.

[0110] Optionally, the system further includes:

[0111] The low-pressure steam drum liquid level monitoring module is used to monitor the liquid level of the low-pressure steam drum in real time.

[0112] The medium and high pressure steam drum water level regulating valve control module is used to obtain the current liquid level deviation of the low pressure steam drum between the current liquid level of the low pressure steam drum and the corresponding target liquid level of the low pressure steam drum; and to adjust the opening degree of the medium pressure steam drum water level regulating valve and / or the high pressure steam drum water level regulating valve according to the current liquid level deviation of the low pressure steam drum.

[0113] Optionally, the system further includes: an automatic control module for the low-pressure steam drum water supply regulating valve, used to control the low-pressure steam drum water level regulating valve to a specified opening degree when the current liquid level deviation of the low-pressure steam drum is less than or equal to a first deviation monitoring value, and the unit is in the first target operation stage, the high and medium pressure steam drums are in the water replenishment process, the low-pressure steam drum water supply regulating valve is in manual control state, and the current liquid level deviation between the current liquid level of the condenser hot well and the target liquid level of the condenser hot well is greater than or equal to a second deviation monitoring value.

[0114] Optionally, the system further includes: an automatic control module for the high-pressure steam drum water level regulating valve, used to monitor the high-pressure steam drum water level in real time; when the current water level in the high-pressure steam drum exceeds a preset first monitoring water level, controlling the high-pressure steam drum water level regulating valve to close and switch to manual control mode; and

[0115] Control the drainage of the high-pressure steam drum to the second monitoring liquid level of the high-pressure steam drum; control the working state of the high-pressure steam drum water level regulating valve according to the current liquid level of the high-pressure steam drum.

[0116] Optionally, the system further includes: a feedforward adaptive control module, used to monitor the current liquid level of each steam drum in real time; and to adaptively control the opening degree of the water supply regulating valve corresponding to each steam drum based on the liquid level deviation between the current liquid level of the steam drum and the corresponding preset liquid level of the steam drum.

[0117] Optionally, the system further includes: a steam drum liquid level target value adaptive adjustment module, used to identify the current operating stage of the unit and configure the preset liquid level of each steam drum corresponding to the current operating stage of the unit.

[0118] Since the functional modules of the boiler feedwater control system based on self-start-stop control in this invention are the same as those in the above-described boiler feedwater control method based on self-start-stop control, they will not be described again here.

[0119] It should be noted that although several modules or units for the device used to perform actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to embodiments of this disclosure, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0120] Furthermore, embodiments of the present invention provide a computer-readable storage medium. Figure 4This is a schematic diagram of a computer-readable storage medium provided for an embodiment of the present invention. Specifically, it stores a program product capable of implementing the methods described above in this specification. In some possible embodiments, various aspects of the present invention can also be implemented as a program product comprising program code, which, when the program product is run on a terminal device, causes the terminal device to perform the steps of the various exemplary embodiments of the present invention described in the "Exemplary Methods" section of this specification.

[0121] According to embodiments of the present invention, a program product for implementing the above-described method may employ a portable compact disc read-only memory (CD-ROM) and include program code, and may run on a terminal device, such as a personal computer. However, the program product of the present invention is not limited thereto. In this document, a readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device.

[0122] The program product may employ any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0123] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable signal medium may also be any readable medium other than a readable storage medium, capable of sending, propagating, or transmitting programs for use by or in conjunction with an instruction execution system, apparatus, or device.

[0124] The program code contained on the readable medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, RF, etc., or any suitable combination thereof.

[0125] Program code for performing the operations of this invention can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, and conventional procedural programming languages ​​such as C or similar languages. The program code can execute entirely on the user's computing device, partially on the user's device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0126] Furthermore, embodiments of the present invention provide an electronic device. Figure 5 This is a schematic diagram of an electronic device provided in an embodiment of the present invention. This electronic device can be used to implement the above-described boiler feedwater control method based on automatic start-stop control. Figure 5 As shown, the electronic device 800 is presented in the form of a general-purpose computing device. The components of the electronic device 800 may include, but are not limited to: at least one processing unit 810, at least one storage unit 820, a bus 830 connecting different system components (including storage unit 820 and processing unit 810), and a display unit 840.

[0127] The storage unit stores program code that can be executed by the processing unit 810, causing the processing unit 810 to perform the steps described in the "Exemplary Methods" section of this specification according to various exemplary embodiments of the present invention. For example, the processing unit 810 can perform actions such as... Figure 2 The steps are shown in the figure.

[0128] Storage unit 820 may include volatile storage units, such as random access memory (RAM) 8201 and / or cache memory 8202, and may further include read-only memory (ROM) 8203.

[0129] The storage unit 820 may also include a program / utility 8204 having a set (at least one) of program modules 8205, including but not limited to: an operating system, one or more application programs, other program modules, and program data, each or some combination of these examples may include an implementation of a network environment.

[0130] Bus 830 may include a data bus, an address bus, and a control bus.

[0131] Electronic device 800 can also communicate with one or more external devices 900 (e.g., keyboard, pointing device, Bluetooth device, etc.) via input / output (I / O) interface 850. Electronic device 800 also includes a display unit 840 connected to input / output (I / O) interface 850 for display purposes. Furthermore, electronic device 800 can communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 860. As shown, network adapter 860 communicates with other modules of electronic device 800 via bus 830. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with electronic device 800, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0132] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention.

Claims

1. A method for full-process control of boiler feedwater based on automatic start-stop control, characterized in that, include: Real-time monitoring of the liquid level in the condenser hot well; During the condenser hot well water replenishment process, when it is confirmed that the opening of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position, and the liquid level of the condensate storage tank is greater than or equal to the first monitored liquid level, the condenser water supply bypass electric valve is controlled to open. When the opening of the condenser water level regulating valve is less than or equal to the second preset condenser water level regulating valve position, the condenser water supply bypass electric valve is controlled to close. When the monitoring shows that the condenser water bypass electric valve is fully open, the opening degree of the condenser water level regulating valve is greater than or equal to the first preset condenser water level regulating valve position, and the liquid level of the condenser hot well is lower than the target liquid level of the condenser hot well, the current liquid level of the condensate storage tank is obtained. If the current liquid level in the condensate storage tank meets the preset start-up conditions, control the condensate delivery pump to start. When the condenser hot well liquid level is monitored to be higher than or equal to the target liquid level of the condenser hot well, and the opening of the condenser water level regulating valve is less than or equal to the valve position of the second preset condenser water level regulating valve, the condensate delivery pump is controlled to shut down.

2. The boiler feedwater control method based on automatic start-stop control according to claim 1, characterized in that, The method further includes: Monitor the liquid level in the condensate storage tank; During the water replenishment process, when the current liquid level of the condensate storage tank is detected to be lower than or equal to the monitored liquid level of the first condensate storage tank, the electric valve for replenishing the condensate storage tank is opened; and When the current liquid level of the condensate storage tank is detected to be higher than or equal to the monitored liquid level of the second condensate storage tank, the electric valve for replenishing water in the condensate storage tank is controlled to close.

3. The boiler feedwater control method based on automatic start-stop control according to claim 1, characterized in that, The method further includes: Obtain the current liquid level deviation of the condenser hot well between the current liquid level of the condenser hot well and the corresponding target monitoring liquid level of the condenser hot well; Adjust the opening of the low-pressure steam drum water level regulating valve according to the current liquid level deviation of the condenser hot well.

4. The boiler feedwater control method based on automatic start-stop control according to claim 1 or 3, characterized in that, The method further includes: Real-time monitoring of the liquid level in the low-pressure steam drum; Obtain the current liquid level deviation of the low-pressure steam drum between the current liquid level of the low-pressure steam drum and the corresponding target liquid level of the low-pressure steam drum; Adjust the opening degree of the medium-pressure steam drum water level regulating valve and / or the high-pressure steam drum water level regulating valve according to the current liquid level deviation of the low-pressure steam drum.

5. The boiler feedwater control method based on self-start-stop control according to claim 4, characterized in that, The method further includes: When the current liquid level deviation of the low-pressure steam drum is less than or equal to the first deviation monitoring value, and the unit is in the first target operation stage, the high and medium pressure steam drums are in the water replenishment process, the water supply regulating valve of the low-pressure steam drum is in manual control mode, and the current liquid level deviation between the current liquid level of the condenser hot well and the target liquid level of the condenser hot well is greater than or equal to the second deviation monitoring value, the low-pressure steam drum water level regulating valve is controlled to the specified opening degree.

6. The boiler feedwater control method based on automatic start-stop control according to claim 4, characterized in that, The method further includes: Real-time monitoring of the liquid level in the high-pressure steam drum; When the current liquid level in the high-pressure steam drum exceeds the preset first monitoring liquid level of the high-pressure steam drum, the high-pressure steam drum water level regulating valve is closed and switched to manual control mode; and Control the high-pressure steam drum to drain to the second monitoring level of the high-pressure steam drum; The operating status of the high-pressure steam drum water level regulating valve is controlled according to the current liquid level of the high-pressure steam drum.

7. The boiler feedwater control method based on automatic start-stop control according to claim 1, characterized in that, The method further includes: Real-time monitoring of the current liquid level in each steam drum; Based on the level deviation between the current liquid level of the steam drum and the corresponding preset liquid level of the steam drum, the opening degree of the water supply regulating valve corresponding to each steam drum is adaptively controlled.

8. The boiler feedwater control method based on automatic start-stop control according to claim 7, characterized in that, The method further includes: Identify the current operating stage of the unit, and configure the preset liquid level of each steam drum corresponding to the current operating stage of the unit.

9. A storage medium, characterized in that, It stores a computer program, which, when executed by a processor, implements the boiler feedwater full-process control method based on self-start-stop control according to any one of claims 1 to 8.

10. An electronic device, characterized in that, include: processor; as well as Memory for storing the executable instructions of the processor; The processor is configured to execute the boiler feedwater full-process control method based on self-start-stop control as described in any one of claims 1 to 8 by executing the executable instructions.

Images