A flue gas baffle self-adaptive adjustment control method and system considering main steam temperature regulation

Abstract

The application discloses a flue gas baffle self-adaptive adjustment control method and system considering main steam temperature regulation, and comprises the following steps: obtaining real-time temperature values and set values of reheated steam and main steam of a coal-fired unit; calculating a first deviation value of the reheated steam temperature, performing first preprocessing to obtain a reheated flue gas baffle instruction; combining the main steam temperature related value and the first deviation value, performing second preprocessing to obtain a self-adaptive adjustment value of a flue gas baffle opening degree; and obtaining a superheated flue gas baffle instruction according to the sum of the reheated flue gas baffle instruction, the flue gas baffle opening degree self-adaptive adjustment value and a preset minimum flue gas baffle opening degree. The method improves reheated steam temperature regulation flexibility, optimizes main steam temperature control, reduces flue duct throttling loss and improves unit transient operation flexibility.

Description

Technical Field

[0001] This invention relates to the field of thermal control technology for thermal power plants, and in particular to an adaptive adjustment control method and system for flue gas dampers that takes into account both main steam temperature regulation and control. Background Technology

[0002] Currently, the reheat steam temperature in thermal power units is mainly controlled by convective heat transfer, and the regulation method usually involves adjusting the reheater flue gas dampers, with emergency water spray desuperheating as an auxiliary regulation means. However, the water spray desuperheating regulation method has a significant impact on the unit's economy, and this regulation method is only used for emergency water spraying in case of overheating. The traditional flue gas damper regulation method usually fixes the sum of the openings of the reheat side and the superheat side dampers, and the two sides are linked in opposite directions. That is, when the superheat side flue gas damper is closed, the reheat side flue gas damper will be opened, so as to control the reheat steam temperature by changing the flue gas flow through the reheater flue.

[0003] However, in operating conditions where the reheat steam temperature is within a reasonable range but the main steam temperature is severely under-temperatured, under traditional reheat steam temperature control methods, the reheat flue gas damper opening remains unchanged, and the sum of the openings of the reheat and superheat side dampers is fixed. Therefore, the superheat side flue gas damper cannot adjust the main steam temperature, resulting in the flue gas duct being subject to real-time throttling by the damper, leading to high induced draft fan consumption. In conditions where the reheat steam temperature is severely over- or under-temperatured, the superheat flue gas damper can only open and close as the reheat damper opening decreases or vice versa, constrained by the fixed sum of their openings. This limitation on the opening and closing range, due to the fixed sum of their openings, results in poor reheat steam temperature control speed. Therefore, while this flue gas damper control method, which fixes the sum of the reheat and superheat side damper openings, is simple in structure and convenient to operate, it lacks flexibility in adjusting the reheat steam temperature and cannot simultaneously address flue gas throttling losses and main steam temperature control. Therefore, it is necessary to introduce new flue gas damper control methods to improve the regulation performance of main and reheat steam temperatures, thereby fundamentally improving the flexibility of transient processes in coal-fired power units. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0005] In view of the aforementioned existing problems, the present invention is proposed.

[0006] Therefore, the present invention provides a flue gas damper adaptive adjustment control method and system that takes into account the main steam temperature regulation, which can solve the problems mentioned in the background art.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0008] In a first aspect, the present invention provides an adaptive adjustment control method for flue gas dampers that also takes into account main steam temperature regulation, comprising:

[0009] The system acquires the real-time reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, and the setpoint of the main steam temperature of the coal-fired unit, and obtains the first deviation value based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit.

[0010] The real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit are pre-processed to obtain the reheat flue gas damper command.

[0011] The real-time reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, the setpoint of the main steam temperature of the coal-fired unit, and the first deviation value are subjected to a second preprocessing to obtain the adaptive adjustment value of the sum of flue gas damper openings.

[0012] Based on the reheat flue gas damper command and the adaptive adjustment value of the sum of flue gas damper openings, combined with the preset minimum flue gas damper openings, the superheated flue gas damper command is obtained.

[0013] As a preferred embodiment of the flue gas damper adaptive adjustment control method that takes into account the main steam temperature regulation described in this invention, the first deviation value includes the difference between the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit.

[0014] As a preferred embodiment of the flue gas damper adaptive adjustment control method that takes into account main steam temperature regulation as described in this invention, the first preprocessing includes:

[0015] The first preset function converts the coal-fired unit load command into a feedforward control signal for the coal-fired unit reheat flue gas damper command.

[0016] Based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit, the output adjustment value of the real-time reheat steam temperature is obtained in conjunction with the first PID controller.

[0017] The sum of the feedforward control signal for the reheat flue gas damper command of the coal-fired unit and the output adjustment value of the real-time reheat steam temperature is obtained, and the reheat flue gas damper command is obtained according to the first preset limit.

[0018] As a preferred embodiment of the flue gas damper adaptive adjustment control method that takes into account main steam temperature regulation as described in this invention, the second preprocessing includes:

[0019] Based on the real-time value of the main steam temperature at the boiler outlet of the coal-fired unit and the set value of the main steam temperature of the coal-fired unit, and in conjunction with the second PID controller, the sum of the adaptive adjustment values ​​of the opening of the first flue gas damper is obtained.

[0020] Based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit, combined with the third PID controller, the sum of the adaptive adjustment values ​​of the second flue gas damper opening is obtained.

[0021] The system determines whether the first deviation value is reasonable by using a first preset deviation threshold, and outputs the corresponding adaptive adjustment value of the sum of flue gas damper openings based on the determination result.

[0022] As a preferred embodiment of the flue gas damper adaptive adjustment control method that takes into account main steam temperature regulation as described in this invention, the second preprocessing further includes:

[0023] The first deviation value is determined to be reasonable by using a first preset deviation threshold.

[0024] If reasonable, the adaptive adjustment value of the sum of the openings of the first flue gas dampers will be limited by the second preset limit, and the adaptive adjustment value of the sum of the openings of the first flue gas dampers after the limiting operation will be output.

[0025] If it is unreasonable, the adaptive adjustment value of the sum of the openings of the second flue gas dampers will be limited by the second preset limit, and the adaptive adjustment value of the sum of the openings of the second flue gas dampers after the limitation operation will be output.

[0026] As a preferred embodiment of the flue gas damper adaptive adjustment control method that also considers main steam temperature regulation as described in this invention, the first preset function includes:

[0027] The first preset function is expressed as:

[0028] F(Pe)=a·Pe 2 +b·Pe+c

[0029] Where F(Pe) represents the first preset function, Pe is the load command of the coal-fired unit in MW, and a, b, and c are the identification parameters of the coal-fired unit, where a < 0.

[0030] As a preferred embodiment of the flue gas damper adaptive adjustment control method that takes into account main steam temperature regulation as described in this invention, the step of obtaining the superheated flue gas damper command based on the reheat flue gas damper command and the sum of flue gas damper openings adaptive adjustment values, combined with the preset minimum flue gas damper openings, includes:

[0031] Obtain the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing;

[0032] The difference between the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing, and the reheat flue gas damper command obtained after the first preprocessing;

[0033] The difference between the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing, and the reheat flue gas damper command obtained after the first preprocessing, is taken as the superheated flue gas damper command.

[0034] Secondly, the present invention provides an adaptive adjustment control system for flue gas dampers that also considers main steam temperature regulation, comprising:

[0035] The data acquisition module is used to acquire the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time value of the main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, and the setpoint of the main steam temperature of the coal-fired unit, and to acquire the first deviation value based on the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit.

[0036] The first preprocessing module is used to perform first preprocessing on the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit to obtain the reheat flue gas damper command.

[0037] The second preprocessing module is used to perform second preprocessing on the real-time value of reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time value of main steam temperature at the boiler outlet of the coal-fired unit, the set value of reheat steam temperature of the coal-fired unit, the set value of main steam temperature of the coal-fired unit, and the first deviation value to obtain the adaptive adjustment value of the sum of flue gas damper opening.

[0038] The instruction acquisition module is used to acquire the superheated flue gas damper instruction based on the reheated flue gas damper instruction and the sum of flue gas damper openings, combined with the preset minimum flue gas damper openings.

[0039] Thirdly, the present invention provides a computer device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described above.

[0040] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described above.

[0041] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention proposes an adaptive adjustment control method and system for flue gas dampers that takes into account the main steam temperature regulation. It acquires the real-time reheat steam temperature at the boiler outlet of a coal-fired power unit, the real-time main steam temperature at the boiler outlet of a coal-fired power unit, the setpoint for the reheat steam temperature of the coal-fired power unit, and the setpoint for the main steam temperature of the coal-fired power unit. A first deviation value is obtained based on the real-time reheat steam temperature at the boiler outlet of the coal-fired power unit and the setpoint for the reheat steam temperature of the coal-fired power unit. The system then adjusts the real-time reheat steam temperature at the boiler outlet of the coal-fired power unit and the setpoint for the main steam temperature of the coal-fired power unit. The reheat steam temperature setpoint of the coal-fired power unit undergoes a first preprocessing step to obtain a reheat flue gas damper command. A second preprocessing step is performed on the real-time reheat steam temperature at the boiler outlet of the coal-fired power unit, the real-time main steam temperature at the boiler outlet of the coal-fired power unit, the reheat steam temperature setpoint of the coal-fired power unit, the main steam temperature setpoint of the coal-fired power unit, and a first deviation value to obtain an adaptive adjustment value for the sum of flue gas damper openings. Based on the reheat flue gas damper command and the adaptive adjustment value for the sum of flue gas damper openings, combined with the preset minimum sum of flue gas damper openings, a superheated flue gas damper command is obtained. This improves the flexibility of reheat steam temperature adjustment for the coal-fired power unit under different operating conditions, while optimizing main steam temperature control, reducing flue gas throttling losses, and enhancing the flexibility of the unit's transient operation.

[0042] In addition, by adaptively adjusting the sum of the openings of the reheat side and the superheat side dampers, the speed of reheat steam temperature control can be improved while taking into account the main steam temperature control, thus reducing the throttling losses of the flue gas dampers. This control method allows for several advantages. For operating conditions where the reheat steam temperature is within a reasonable range but the main steam temperature is severely under-temperatured, the superheated flue gas damper can continue to open wider without being limited by the fixed sum of the openings of the reheat and superheated side dampers, while ensuring a reasonable reheat steam temperature. This increases the main steam temperature and reduces the throttling losses in the flue gas duct. For operating conditions where the reheat steam temperature is severely over-temperatured, the reheated flue gas damper closes, and the sum of the openings of the reheat and superheated side dampers increases, ultimately leading to a rapid opening of the superheated flue gas damper. Conversely, for operating conditions where the reheat steam temperature is severely under-temperatured, the reheated flue gas damper opens wider, and the sum of the openings of the reheat and superheated side dampers decreases, leading to a rapid closing of the superheated flue gas damper. Therefore, for operating conditions where the reheat steam temperature is severely over- or under-temperatured, the reheat and superheated flue gas dampers operate simultaneously with greater amplitude, resulting in a faster reheat steam temperature adjustment. Attached Figure Description

[0043] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0044] Figure 1A flowchart of a flue gas damper adaptive adjustment control method and system that takes into account main steam temperature regulation is provided in one embodiment of the present invention.

[0045] Figure 2 A schematic diagram of the flue gas damper temperature regulation structure of a coal-fired unit flue gas damper adaptive adjustment control method and system that takes into account the main steam temperature regulation, provided in an embodiment of the present invention.

[0046] Figure 3 A control logic diagram of a flue gas damper adaptive adjustment control method and system that takes into account main steam temperature regulation is provided in one embodiment of the present invention.

[0047] Figure 4 An effect diagram of a flue gas damper adaptive adjustment control method and system that takes into account main steam temperature regulation, provided in an embodiment of the present invention;

[0048] Figure 5 This is an internal structural diagram of a computer device for an adaptive adjustment control method and system for flue gas dampers that also takes into account main steam temperature regulation, provided as an embodiment of the present invention. Detailed Implementation

[0049] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. 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 protection scope of the present invention.

[0050] Example 1

[0051] Reference Figures 1-5 This is the first embodiment of the present invention. This embodiment provides a flue gas damper adaptive adjustment control method and system that takes into account main steam temperature regulation, including a flue gas damper adaptive adjustment control method and a flue gas damper adaptive adjustment control system that takes into account main steam temperature regulation. The flue gas damper adaptive adjustment control method that takes into account main steam temperature regulation includes:

[0052] Before detailing the embodiments of this application, some related concepts will be explained for clarity.

[0053] PID Controller: A PID controller (Proportional-Integral-Derivative Controller) is a widely used closed-loop control strategy for automatically regulating various industrial processes, ensuring that the controlled variable (such as temperature, pressure, speed, etc.) closely tracks the setpoint. A PID controller operates through three basic operations: Proportional (P): Adjusts the output based on the magnitude of the current error; the larger the error, the stronger the correction. Integral (I): Considers the cumulative effect of the error over time, used to eliminate static errors; even with small but persistent errors, the controller gradually increases the output to correct them. Derivative (D): Predicts the trend of error changes; if the error changes rapidly, the controller makes larger adjustments in advance, helping to reduce overshoot and oscillation.

[0054] Direct and reverse action of PID controllers: If the input deviation signal of a PID controller is defined as the real-time value minus the set value, then a PID controller whose output increases as the deviation increases is called a "direct action" PID controller; conversely, a PID controller whose output signal decreases as the deviation increases is called a "reverse action" PID controller.

[0055] In existing technologies, the flue gas damper regulation method for coal-fired units typically fixes the sum of the openings of the reheat and superheat side dampers, with the two dampers linked in opposite directions. That is, when the superheat side flue gas damper is closed, the reheat side flue gas damper opens, thereby controlling the reheat steam temperature by changing the flue gas flow through the reheater flue. However, this traditional flue gas damper regulation method cannot simultaneously control the main steam temperature, and it has certain limitations in terms of response speed and system economy for reheat steam temperature control.

[0056] This application provides a method that can effectively solve the problems existing in the prior art. The following will describe in detail how to implement the flue gas damper adaptive adjustment control method that takes into account the main steam temperature regulation, with a combination of multiple embodiments.

[0057] Figure 1 A flowchart illustrating an adaptive adjustment control method and system for flue gas dampers that also considers main steam temperature regulation is provided, including:

[0058] S101, acquire the real-time value of reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time value of main steam temperature at the boiler outlet of the coal-fired unit, the set value of reheat steam temperature of the coal-fired unit, and the set value of main steam temperature of the coal-fired unit, and acquire the first deviation value based on the real-time value of reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of reheat steam temperature of the coal-fired unit.

[0059] The first deviation value includes the difference between the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit.

[0060] In this embodiment of the application, the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit is recorded as R. PV The reheat steam temperature setpoint for coal-fired units is R. SP The difference between the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint reheat steam temperature of the coal-fired unit is denoted as R. E ;

[0061] Among them, R E =R SP -R PV .

[0062] In an optional embodiment, the reheat steam temperature setpoint and the main steam temperature setpoint of the coal-fired unit can be determined by the coal-fired unit design specifications and operating regulations. The ideal temperature settings for reheat steam and main steam during normal operation of the coal-fired unit can be obtained by the design specifications and operating regulations to ensure the stable operation and efficiency of the unit.

[0063] In this embodiment, the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the real-time main steam temperature at the boiler outlet of the coal-fired unit can be obtained by a temperature sensor preset at the boiler outlet of the coal-fired unit.

[0064] In an optional embodiment, when setting a temperature sensor, if a single temperature sensor is used, it is positioned at the center of the main steam pipe or reheat steam pipe, where the temperature is more representative of the average temperature of the entire steam flow and is less susceptible to the influence of localized hot spots or cold spots. This arrangement is beneficial for reflecting the overall steam condition.

[0065] In an optional embodiment, when setting temperature sensors, if at least two temperature sensors are set, the sensors can be set at different locations in the steam pipeline (such as the upper, middle, and lower parts), and the average value of the sensors can be used as the real-time value. Sensors can also be set at important nodes in the steam flow direction, such as the boiler outlet, superheater outlet, and reheater outlet, and the real-time temperature value can be calculated by different weights. This design can better monitor the efficiency and stability of the entire steam thermodynamic cycle. Redundant sensors can also be set at critical locations, so that even if one sensor fails, the unit can continue to operate based on the data of other sensors, ensuring that the unit will not shut down due to a single sensor failure.

[0066] It should be noted that by acquiring real-time reheat steam temperature and main steam temperature, as well as preset temperature setpoints, the deviation between the current operating state and the target state can be reflected in real time, providing a basis for subsequent adaptive adjustments. The first deviation value reflects the control requirements of the reheat steam temperature and is a key parameter for adjusting the flue gas damper opening.

[0067] S102, perform the first preprocessing on the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit to obtain the reheat flue gas damper command.

[0068] The first preprocessing includes:

[0069] The first preset function converts the coal-fired unit load command into a feedforward control signal for the coal-fired unit reheat flue gas damper command.

[0070] Based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit, the output adjustment value of the real-time reheat steam temperature is obtained in conjunction with the first PID controller.

[0071] The sum of the feedforward control signal for the reheat flue gas damper command of the coal-fired unit and the output adjustment value of the real-time reheat steam temperature is obtained, and the reheat flue gas damper command is obtained according to the first preset limit.

[0072] Specifically, the first preset function includes:

[0073] The first preset function is expressed as:

[0074] F(Pe)=a·Pe 2 +b·Pe+c

[0075] Where F(Pe) represents the first preset function, Pe is the load command of the coal-fired unit in MW, and a, b, and c are the identification parameters of the coal-fired unit, where a < 0.

[0076] In this embodiment, the load command of the coal-fired unit is denoted as Pe, and the feedforward control signal of the reheat flue gas damper command of the coal-fired unit is denoted as F. fd ;

[0077] Among them, F fd =F(Pe).

[0078] In this embodiment, the first PID controller is a "reverse" PID controller, which converts the obtained reheat steam temperature setpoint R... SP Real-time value of reheat steam temperature R PV The output adjustment value F for the real-time reheat steam temperature is obtained by inputting the "reaction" PID controller. PID And based on the feedforward control signal F of the reheat flue gas damper command obtained from the coal-fired unit fd After passing the first preset limit, the final reheat flue gas damper command μ is obtained. R Feedforward control signal F fd For steady-state control signal, F PIDThe dynamic control signal is added to the steady-state control signal to obtain the total reheat flue gas damper command μ. R ...

[0079] In this embodiment of the application, the first preset limit can be set by a high / low limit monitor or other hardware limit.

[0080] In an optional embodiment, the specific value of the first preset limit can be determined by the following steps:

[0081] First, obtain the design specifications and safety operation manuals for reference coal-fired units (these documents may contain suggestions or requirements regarding the limitation of flue gas damper opening) and establish a mathematical model of the thermal system of the coal-fired unit.

[0082] Secondly, by establishing a mathematical model of the thermal system of a coal-fired power unit and using simulation software (such as MATLAB / Simulink, Aspen HYSYS, etc.) for dynamic simulation, the performance of the PID controller can be tested under different operating conditions. During the simulation, the range of the control signal can be observed, and appropriate limits can be determined to ensure that the control output does not cause the system to operate beyond its limits or damage the equipment.

[0083] Secondly, in actual operation, the system response is observed by gradually adjusting the PID parameters and limits, paying particular attention to whether the controller output remains within a safe and effective range under various boundary conditions and abnormal situations. This process often requires repeated trials and optimizations, determining the optimal limits based on field commissioning data and operational experience.

[0084] Finally, when setting limits, a certain safety margin should be left, that is, the upper and lower limits of the controller's output should be lower than the actual operating limits of the equipment by a certain percentage, in order to prevent control errors caused by unexpected situations.

[0085] In an optional embodiment, the specific value of the first preset limit can also be set directly based on the operator's experience;

[0086] In the embodiments of this application, the specific value of the first preset limit is 0%-100%, but other first preset limits obtained according to the above steps or similar steps should be within the protection scope of this application.

[0087] It should be noted that the first preprocessing step combines the load command of the coal-fired unit with the real-time reheat steam temperature, taking into account the dual functions of feedforward and feedback control. The feedforward control signal can pre-adjust the reheat flue gas damper according to load changes, while the PID controller makes real-time adjustments based on the deviation between the actual temperature and the set value, ensuring precise control of the reheat steam temperature. Simultaneously, the setting of the first preset limit prevents equipment safety issues caused by excessive control signals, ensuring the stable operation of the coal-fired unit under various operating conditions.

[0088] S103, perform a second preprocessing on the real-time value of reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time value of main steam temperature at the boiler outlet of the coal-fired unit, the set value of reheat steam temperature of the coal-fired unit, the set value of main steam temperature of the coal-fired unit, and the first deviation value to obtain the adaptive adjustment value of the sum of flue gas damper opening.

[0089] The second preprocessing includes:

[0090] Based on the real-time value of the main steam temperature at the boiler outlet of the coal-fired unit and the set value of the main steam temperature of the coal-fired unit, and in conjunction with the second PID controller, the sum of the adaptive adjustment values ​​of the opening of the first flue gas damper is obtained.

[0091] Based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit, combined with the third PID controller, the sum of the adaptive adjustment values ​​of the second flue gas damper opening is obtained.

[0092] The system determines whether the first deviation value is reasonable by using a first preset deviation threshold, and outputs the corresponding adaptive adjustment value of the sum of flue gas damper openings based on the determination result.

[0093] Furthermore, the second preprocessing also includes:

[0094] The first deviation value is determined to be reasonable by using a first preset deviation threshold.

[0095] If reasonable, the adaptive adjustment value of the sum of the openings of the first flue gas dampers will be limited by the second preset limit, and the adaptive adjustment value of the sum of the openings of the first flue gas dampers after the limiting operation will be output.

[0096] If it is unreasonable, the adaptive adjustment value of the sum of the openings of the second flue gas dampers will be limited by the second preset limit, and the adaptive adjustment value of the sum of the openings of the second flue gas dampers after the limitation operation will be output.

[0097] In this embodiment, the second PID controller is a "reverse-acting" PID controller, and the third PID controller is a "direct-acting" PID controller. The main steam temperature setpoint of the coal-fired unit is denoted as S. SP The real-time value of the main steam temperature at the boiler outlet of a coal-fired unit is denoted as S. PVThe obtained main steam temperature setpoint S SP and the real-time value of the main steam temperature S PV The input is fed into the "reaction" PID controller to obtain the adaptive adjustment value F, which is the sum of the flue gas damper openings that take into account the main steam temperature regulation. NPID The reheat steam temperature setpoint R of the coal-fired unit is set. SP Real-time value R of reheat steam temperature at the boiler outlet of coal-fired unit PV The input to the "positive-acting" PID controller yields the adaptive adjustment value F, which is the sum of the flue gas damper openings used to rapidly regulate the reheat steam temperature. YPID .

[0098] In this embodiment of the application, the first preset deviation threshold is set to ±4℃.

[0099] In an optional embodiment, the first preset deviation threshold is implemented using a high / low limit monitor, which can be obtained by constructing a system mathematical model, using simulation tools, or through expert experience.

[0100] In the embodiments of this application, the adaptive adjustment value of the sum of the openings of the first flue gas damper is the adaptive adjustment value of the sum of the openings of the flue gas damper that takes into account the main steam temperature regulation, and the adaptive adjustment value of the sum of the openings of the second flue gas damper is the adaptive adjustment value of the sum of the openings of the flue gas damper that rapidly regulates the reheat steam temperature.

[0101] In an optional embodiment, the specific steps for obtaining the second preset limit value can be the same as or different from the specific steps for obtaining the first preset limit value.

[0102] In this embodiment of the application, the real-time deviation value R of the reheat steam temperature is determined. E Whether it is within a reasonable range, select the adaptive adjustment value μA for the sum of flue gas damper openings;

[0103] If R E If it is within a reasonable range, then choose F. NPID After being limited by the large and small amplitudes of the second preset limit, μA is formed, that is:

[0104] μA=F NPID ;

[0105] If R E If it exceeds the reasonable range, select F. YPID After being limited by the large and small amplitudes of the second preset limit, μA is formed, that is:

[0106] μA=F YPID ;

[0107] In this application embodiment, the large and small limit operations of the second preset limit are specifically taken as 0 to 80%, but other second preset limits obtained according to the above steps or similar steps should be within the protection scope of this application.

[0108] It should be noted that by combining the real-time and setpoint values ​​of the main steam temperature and reheat steam temperature, and employing PID controllers with different characteristics, precise and flexible adjustment of the flue gas damper opening is achieved. The adaptive adjustment value of the sum of the first flue gas damper openings primarily focuses on the stability of the main steam temperature, while the adaptive adjustment value of the sum of the second flue gas damper openings emphasizes rapid response to changes in the reheat steam temperature. By judging the first preset deviation threshold, either the first or second flue gas damper opening is selected as the adaptive adjustment value. Furthermore, through amplitude limiting operation, it can be ensured that during the control process, whether under normal or abnormal conditions, the equipment operation can be effectively prevented from exceeding the safe range due to excessive control signals, thereby improving the safety and stability of the entire coal-fired unit operation.

[0109] Furthermore, by setting different limiting thresholds, the system can be dynamically adjusted according to actual operating conditions and equipment performance, increasing its adaptability. This adaptive adjustment not only considers the operating limits of the equipment but also potential environmental changes and operator experience, making the control method more intelligent and reliable. This innovative control method significantly improves the thermal efficiency and service life of coal-fired units, reduces maintenance costs, and has important practical significance for the safe and efficient operation of large-scale thermal power systems.

[0110] S104: Based on the reheat flue gas damper command and the sum of flue gas damper openings adaptive adjustment values, combined with the preset minimum flue gas damper openings, the superheated flue gas damper command is obtained.

[0111] Based on the reheat flue gas damper command and the adaptive adjustment value of the sum of flue gas damper openings, combined with the preset minimum flue gas damper opening, the superheated flue gas damper command is obtained, including:

[0112] Obtain the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing;

[0113] The difference between the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing, and the reheat flue gas damper command obtained after the first preprocessing;

[0114] The difference between the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing, and the reheat flue gas damper command obtained after the first preprocessing, is taken as the superheated flue gas damper command.

[0115] In this embodiment, the real-time sum of flue gas damper openings μ is obtained by adding the sum of the minimum flue gas damper openings μmin manually set by the unit operator to the adaptive adjustment value μA of the sum of flue gas damper openings, i.e.:

[0116] μ = μ A +μ min ;

[0117] Based on the sum μ of the flue gas damper openings obtained above and the reheat flue gas damper command μ R The difference is calculated to obtain the final superheated flue gas damper command μ. S ,Right now

[0118] μ S =μ-μ R ;

[0119] It should be noted that the flue gas damper adjustment control, which takes into account the main steam temperature regulation, can be completed based on the obtained superheated flue gas damper command. The unit is percentage. For example, when the obtained superheated flue gas damper command is 30%, it means that the damper opens 30% of its full stroke (0~100%).

[0120] In summary, this invention proposes an adaptive adjustment control method for flue gas dampers that takes into account main steam temperature regulation. It acquires the real-time reheat steam temperature at the boiler outlet of a coal-fired power unit, the real-time main steam temperature at the boiler outlet of a coal-fired power unit, the setpoint for the reheat steam temperature of the coal-fired power unit, and the setpoint for the main steam temperature of the coal-fired power unit. A first deviation value is obtained based on the real-time reheat steam temperature at the boiler outlet of the coal-fired power unit and the setpoint for the reheat steam temperature of the coal-fired power unit. The method then adjusts the real-time reheat steam temperature at the boiler outlet of the coal-fired power unit and the setpoint for the reheat steam temperature of the coal-fired power unit. The temperature setpoint undergoes a first preprocessing step to obtain the reheat flue gas damper command. A second preprocessing step is performed on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time main steam temperature at the boiler outlet of the coal-fired unit, the reheat steam temperature setpoint of the coal-fired unit, the main steam temperature setpoint of the coal-fired unit, and a first deviation value to obtain an adaptive adjustment value for the sum of flue gas damper openings. Based on the reheat flue gas damper command and the adaptive adjustment value for the sum of flue gas damper openings, combined with the preset minimum sum of flue gas damper openings, the superheated flue gas damper command is obtained. This improves the flexibility of reheat steam temperature adjustment for coal-fired units under different operating conditions, while optimizing main steam temperature control, reducing flue gas throttling losses, and enhancing the flexibility of transient unit operation. Furthermore, through the adaptive adjustment of the sum of the reheat and superheated side damper openings, the speed of reheat steam temperature control can be improved while also considering main steam temperature control, reducing flue gas damper throttling losses in the flue gas duct. This control method allows for several advantages. For operating conditions where the reheat steam temperature is within a reasonable range but the main steam temperature is severely under-temperatured, the superheated flue gas damper can continue to open wider without being limited by the fixed sum of the openings of the reheat and superheated side dampers, while ensuring a reasonable reheat steam temperature. This increases the main steam temperature and reduces the throttling losses in the flue gas duct. For operating conditions where the reheat steam temperature is severely over-temperatured, the reheated flue gas damper closes, and the sum of the openings of the reheat and superheated side dampers increases, ultimately leading to a rapid opening of the superheated flue gas damper. Conversely, for operating conditions where the reheat steam temperature is severely under-temperatured, the reheated flue gas damper opens wider, and the sum of the openings of the reheat and superheated side dampers decreases, leading to a rapid closing of the superheated flue gas damper. Therefore, for operating conditions where the reheat steam temperature is severely over- or under-temperatured, the reheat and superheated flue gas dampers operate simultaneously with greater amplitude, resulting in a faster reheat steam temperature adjustment.

[0121] This embodiment also provides a flue gas damper adaptive adjustment control system that takes into account main steam temperature regulation, including:

[0122] The data acquisition module is used to acquire the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time value of the main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, and the setpoint of the main steam temperature of the coal-fired unit, and to acquire the first deviation value based on the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit.

[0123] The first preprocessing module is used to perform first preprocessing on the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit to obtain the reheat flue gas damper command.

[0124] The second preprocessing module is used to perform second preprocessing on the real-time value of reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time value of main steam temperature at the boiler outlet of the coal-fired unit, the set value of reheat steam temperature of the coal-fired unit, the set value of main steam temperature of the coal-fired unit, and the first deviation value to obtain the adaptive adjustment value of the sum of flue gas damper opening.

[0125] The instruction acquisition module is used to acquire the superheated flue gas damper instruction based on the reheat flue gas damper instruction and the sum of flue gas damper openings, combined with the preset minimum flue gas damper openings.

[0126] The above-mentioned unit modules can be embedded in the processor of the computer device in hardware form or independent of it, or they can be stored in the memory of the computer device in software form, so that the processor can call and execute the corresponding operations of the above modules.

[0127] This embodiment also provides a computer device, which may be a terminal, and its internal structure diagram may be as follows. Figure 5 As shown. The computer device includes a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements an adaptive adjustment control method for flue gas dampers that also considers main steam temperature regulation. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device casing, or an external keyboard, touchpad, or mouse.

[0128] This embodiment also provides a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, it performs the following steps:

[0129] The system acquires the real-time reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, and the setpoint of the main steam temperature of the coal-fired unit, and obtains the first deviation value based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit.

[0130] The real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit are pre-processed to obtain the reheat flue gas damper command.

[0131] The real-time reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, the setpoint of the main steam temperature of the coal-fired unit, and the first deviation value are subjected to a second preprocessing to obtain the adaptive adjustment value of the sum of flue gas damper openings.

[0132] Based on the reheat flue gas damper command and the adaptive adjustment value of the sum of flue gas damper openings, combined with the preset minimum flue gas damper opening, the superheated flue gas damper command is obtained.

[0133] Example 2

[0134] Reference Figures 2-4 As an embodiment of the present invention, a flue gas damper adaptive adjustment control method and system that takes into account the main steam temperature regulation is provided. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through experiments.

[0135] In this embodiment, a coal-fired unit has a rated load of 600MW, is a single-stage intermediate reheat unit, with a main steam temperature setpoint of 571℃ and a reheat steam temperature setpoint of 569℃. Using the traditional control method, the sum of the openings of the reheat flue gas damper and the superheated flue gas damper is fixed at 120%. During a transient process, when the real-time reheat steam temperature is lower than 569℃ and the main steam temperature is lower than the setpoint of 571℃, the reheat flue gas damper is fully open (100% opening). At this time, the superheated flue gas damper cannot simultaneously regulate the main steam temperature; that is, the superheated flue gas damper opening remains unchanged at 20%. When the control method of this application is used in this transient process, since the superheated flue gas damper also regulates the main steam temperature, when the main steam temperature is lower than the set value of 571°C, the adaptive adjustment value of the flue gas damper increases, causing the superheated flue gas damper to continue to open to 50%, thereby increasing the main steam temperature by 2°C; and during the process, the reheated steam temperature is within a reasonable range (i.e., within ±4°C of the set value). At this time, the opening of the reheated flue gas damper is still maintained at 100%, and the sum of the openings of the two is 150%, thus reducing the throttling loss of the flue.

[0136] In summary, the control method of this application can improve the speed of reheat steam temperature control while taking into account the main steam temperature control through adaptive adjustment of the sum of the openings of the reheat side and the superheat side dampers, and reduce the throttling loss of the flue gas dampers.

[0137] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

[0138] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0139] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0140] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0141] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0142] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0143] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A flue gas damper adaptive adjustment control method that also considers main steam temperature regulation, characterized in that, include: The system acquires the real-time reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, and the setpoint of the main steam temperature of the coal-fired unit, and obtains the first deviation value based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit. The real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit are pre-processed to obtain the reheat flue gas damper command. The real-time reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, the setpoint of the main steam temperature of the coal-fired unit, and the first deviation value are subjected to a second preprocessing to obtain the adaptive adjustment value of the sum of flue gas damper openings. Based on the reheat flue gas damper command and the adaptive adjustment value of the sum of flue gas damper openings, combined with the preset minimum flue gas damper openings, the superheated flue gas damper command is obtained. The second preprocessing includes: Based on the real-time value of the main steam temperature at the boiler outlet of the coal-fired unit and the set value of the main steam temperature of the coal-fired unit, and in conjunction with the second PID controller, the sum of the adaptive adjustment values ​​of the opening of the first flue gas damper is obtained. Based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit, combined with the third PID controller, the sum of the adaptive adjustment values ​​of the second flue gas damper opening is obtained. The first deviation value is determined to be reasonable by using the first preset deviation threshold, and the corresponding sum of flue gas damper openings is output as an adaptive adjustment value based on the determination result. The second preprocessing also includes: The first deviation value is determined to be reasonable by using a first preset deviation threshold. If reasonable, the adaptive adjustment value of the sum of the openings of the first flue gas dampers will be limited by the second preset limit, and the adaptive adjustment value of the sum of the openings of the first flue gas dampers after the limiting operation will be output. If it is unreasonable, the adaptive adjustment value of the sum of the openings of the second flue gas dampers will be limited by the second preset limit, and the adaptive adjustment value of the sum of the openings of the second flue gas dampers after the limitation operation will be output.

2. The flue gas damper adaptive adjustment control method that also considers main steam temperature regulation as described in claim 1, characterized in that, The first deviation value includes the difference between the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit.

3. The flue gas damper adaptive adjustment control method that also considers main steam temperature regulation as described in claim 2, characterized in that, The first preprocessing includes: The first preset function converts the coal-fired unit load command into a feedforward control signal for the coal-fired unit reheat flue gas damper command. Based on the real-time reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit, the output adjustment value of the real-time reheat steam temperature is obtained in conjunction with the first PID controller. The sum of the feedforward control signal for the reheat flue gas damper command of the coal-fired unit and the output adjustment value of the real-time reheat steam temperature is obtained, and the reheat flue gas damper command is obtained according to the first preset limit.

4. The flue gas damper adaptive adjustment control method that also considers main steam temperature regulation as described in claim 3, characterized in that, The first preset function includes: The first preset function is expressed as: ， in, This represents the first preset function. This is a load command for coal-fired power units, in MW. , , Identify parameters for coal-fired power units. .

5. The flue gas damper adaptive adjustment control method that also considers main steam temperature regulation as described in claim 4, characterized in that, The step of obtaining the superheated flue gas damper command based on the sum of the reheated flue gas damper command and the flue gas damper opening value, combined with the preset minimum flue gas damper opening, includes: Obtain the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing; The difference between the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing, and the reheat flue gas damper command obtained after the first preprocessing; The difference between the sum of the preset minimum flue gas damper opening and the adaptive adjustment value of the sum of the flue gas damper opening obtained after the second preprocessing, and the reheat flue gas damper command obtained after the first preprocessing, is taken as the superheated flue gas damper command.

6. A flue gas damper adaptive adjustment control system that incorporates the method described in claim 1, while also considering main steam temperature regulation, characterized in that, include: The data acquisition module is used to acquire the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time value of the main steam temperature at the boiler outlet of the coal-fired unit, the setpoint of the reheat steam temperature of the coal-fired unit, and the setpoint of the main steam temperature of the coal-fired unit, and to acquire the first deviation value based on the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the setpoint of the reheat steam temperature of the coal-fired unit. The first preprocessing module is used to perform first preprocessing on the real-time value of the reheat steam temperature at the boiler outlet of the coal-fired unit and the set value of the reheat steam temperature of the coal-fired unit to obtain the reheat flue gas damper command. The second preprocessing module is used to perform second preprocessing on the real-time value of reheat steam temperature at the boiler outlet of the coal-fired unit, the real-time value of main steam temperature at the boiler outlet of the coal-fired unit, the set value of reheat steam temperature of the coal-fired unit, the set value of main steam temperature of the coal-fired unit, and the first deviation value to obtain the adaptive adjustment value of the sum of flue gas damper opening. The instruction acquisition module is used to acquire the superheated flue gas damper instruction based on the reheated flue gas damper instruction and the sum of flue gas damper openings, combined with the preset minimum flue gas damper openings.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 5.

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