A control device and method applied to a blower RB working condition

Abstract

The application discloses a control device and method applied to a running mode of a blower, relates to the technical field of automatic control of thermal power plants, and mainly has the following technical scheme: one communication door is arranged between two blower running modes and between two primary air fans, when the blower is running, the communication door is triggered to be fully opened, so that sufficient air inlet quantity is ensured to stabilize the furnace negative pressure, and a feedforward processing module is arranged for the primary air fan on each side equipment running mode, so that the blower running signal is additionally arranged as a feedforward signal for the primary air fan movable vane opening degree control, the primary air fan movable vane is triggered to perform additional action to increase the output when the blower is running, according to the improvement of the control device, the control method that the communication door is fully opened and the newly-added feedforward control strategy cooperate with each other is realized, the tripping of the air preheater and the whole air and smoke system is avoided to the greatest extent, the furnace negative pressure is stabilized, and the safety of the unit and the power grid is ensured.

Description

Technical Field

[0001] This application relates to the field of automatic control technology for thermal power plants, and in particular to a control device and method applied to the operation of the blower RB. Background Technology

[0002] In the operation of thermal power units, "Run Back" (RB) is a core protection function that maintains stable operation by rapidly reducing the load when critical auxiliary equipment fails. The RB function can ensure the safety of the unit, avoid cascading failures, reduce the number of unscheduled shutdowns, reduce start-up and shutdown costs, extend equipment life, and enhance the grid support capacity.

[0003] Currently, primary air fan recirculation (RB) poses a significant risk to conventional units. Improper handling could lead to drastic fluctuations in furnace pressure, potentially resulting in fire suppression, furnace deflagration, severe fluctuations in main steam pressure and temperature, equipment damage, and unit tripping. Compared to conventional units, in some specifically designed units, the primary air fan inlet air volume is derived from the diversion of the forced draft fan outlet air volume. This means that, in addition to considering the risk of primary air fan RB, if forced draft fan RB occurs, the inlet air of the primary air fan on the same side will be cut off. Furthermore, if the unit does not respond promptly, forced draft fan RB can trigger primary air fan surge, unstable furnace negative pressure, and in severe cases, furnace fire suppression and tripping of the entire flue gas system. This poses a significant threat to the frequency stability and overall security of the power grid.

[0004] It is evident that in the unit with the specific design described above, the risk of the blower RB actually exceeds that of the primary blower RB. Therefore, how to provide a blower control device for the unit with the specific design to deal with the risk of the blower RB is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] This application provides a control device and method for use in the RB condition of the blower. The main purpose is to provide a control device for the blower in a specially designed unit so that the primary air pressure and furnace negative pressure can still be kept stable when the blower is in RB condition, thereby ensuring the safe and stable operation of the unit and the power grid.

[0006] To achieve the above objectives, this application mainly provides the following technical solutions:

[0007] The first aspect of this application provides a control device for use in the RB operating condition of a blower, the device comprising:

[0008] The system includes a first blower and a second blower, a first primary air fan and a second primary air fan, a secondary air connecting valve and a primary air main pipe connecting valve, a first air preheater and a second air preheater, and a furnace; valves are provided on the pipes connecting different equipment as needed to control and regulate airflow.

[0009] The first blower outlet is divided into two paths, including a first branch and a second branch; the first branch is connected to the inlet of the first primary air blower through a pipeline to provide air source for the first primary air blower; the second branch is connected to the inlet of the first air preheater through a pipeline.

[0010] The outlet of the first primary air blower is connected to the inlet of the first air preheater through a pipeline, and the air pressurized by the first primary air blower is delivered to the first air preheater for heat exchange and to increase the air temperature.

[0011] The outlet of the first air preheater directly sends heated air into the furnace through a pipeline to provide hot air for combustion in the furnace and promote fuel combustion.

[0012] The outlet of the second blower is divided into two paths, including a third branch and a fourth branch; the third branch is connected to the inlet of the second primary air blower through a pipeline to provide air source for the second primary air blower; the fourth branch is connected to the inlet of the second air preheater through a pipeline.

[0013] The outlet of the second primary air fan is connected to the inlet of the second air preheater through a pipeline, and the air pressurized by the second primary air fan is delivered to the second air preheater for heat exchange and to increase the air temperature.

[0014] The outlet of the second air preheater directly sends heated air into the furnace through a pipeline to provide hot air for combustion in the furnace and promote fuel combustion.

[0015] A secondary air connecting valve is provided between the connecting pipes of the first blower and the second blower, and a primary air main pipe connecting valve is provided between the connecting pipes of the first primary air blower and the second primary air blower. When the first blower or the second blower fails, the secondary air connecting valve and the primary air main pipe connecting valve are triggered to fully open, so as to ensure sufficient air intake and stabilize the negative pressure in the furnace.

[0016] A second aspect of this application provides a control method for use with a blower operating under RB conditions, for use with the control device described above for use with a blower operating under RB conditions, the method comprising:

[0017] When the first blower fails, the first blower RB triggers the electric door at the outlet of the first blower to close, and triggers the secondary air connecting door and the primary air main pipe connecting door to open fully;

[0018] During the process of the second blower supplying air to the second primary air fan and the second air preheater, the supplied air is diverted to the first primary air fan and the first air preheater through the secondary air connecting valve and the primary air main connecting valve, to ensure sufficient air intake and stabilize the negative pressure in the furnace; or...

[0019] When the second blower fails, the second blower RB triggers the electric door at the outlet of the second blower to close, and triggers the secondary air connecting door and the primary air main pipe connecting door to open fully;

[0020] During the process of the first blower supplying air to the first primary air blower and the first air preheater, the air is diverted to the second primary air blower and the second air preheater through the secondary air connecting valve and the primary air main pipe connecting valve to ensure sufficient air intake and stabilize the negative pressure in the furnace.

[0021] A third aspect of this application provides a computer program product, including computer instructions, which, when executed by a processor, implement the steps of the control method described above applied to the blower RB operating condition.

[0022] By employing the above-described technical solution, the technical solution provided in this application has at least the following advantages:

[0023] This application provides a control device and method for use under the RB operating condition of the blower. For a specific design unit (the primary air inlet air volume is derived from the split of the blower outlet air volume), this application provides a corresponding blower control device including: the same equipment operating conditions on both sides, in each equipment operating condition, the blower outlet is divided into two paths, one branch is connected to the primary air inlet through a pipeline, the primary air outlet is connected to the air preheater inlet through a pipeline, and the air pressurized by the primary air is delivered to the air preheater. The air preheater outlet is directly delivered to the furnace through a pipeline, providing hot air for combustion in the furnace and promoting fuel combustion; the other branch is connected to the air preheater inlet through a pipeline; and a secondary air connecting door is provided between the two blowers, and a primary air main pipe connecting door is provided between the two primary air fans.

[0024] According to the air supply control device designed above, this application realizes that when the air supply fan fails on either side of the equipment, the inlet air of the primary air fan on the same side is cut off, and at the same time, the secondary air connecting door and the primary air main pipe connecting door are fully opened. Then, the air supply fan that is operating normally on the other side of the equipment can still supply air to the primary air fan and air preheater on the same side through these two connecting doors during the process of supplying air to the primary air fan and air preheater on the same side of the failed air supply fan, thus ensuring sufficient air intake to stabilize the negative pressure in the furnace.

[0025] Compared to the problem in the prior art where the primary air inlet air connected to the blower is cut off due to the blower RB, the blower control device and its corresponding implementation method provided in this application can still maintain the stability of the primary air pressure and furnace negative pressure when the blower RB is activated, thereby ensuring the safe and stable operation of the unit and the power grid.

[0026] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0027] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0028] Figure 1 A block diagram of a control device applied to the RB operating condition of a blower provided in this application embodiment;

[0029] Figure 2 A flowchart of a control method applied to the RB operating condition of a blower provided in this application embodiment;

[0030] Figure 3 A block diagram illustrating the composition of a feedforward processing module provided in an embodiment of this application;

[0031] Figure 4 A flowchart illustrating the method for implementing a feedforward strategy based on a feedforward processing module, as provided in this application embodiment;

[0032] Figure 5 A schematic diagram of the primary wind turbine blade control logic provided in an embodiment of this application. Detailed Implementation

[0033] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0034] The "Run Back" (RB) function of thermal power units is a core protection measure to ensure the safe and stable operation of the unit in the event of a critical auxiliary equipment failure. Its function is reflected in the following aspects:

[0035] To ensure unit safety and avoid cascading failures and unplanned shutdowns: When critical auxiliary equipment such as forced draft fans and induced draft fans trip due to malfunctions, limiting the unit's output capacity, the RB function is quickly triggered to rapidly reduce the load to a level that the remaining auxiliary equipment can handle. This maintains system parameters such as steam-water and combustion (e.g., drum water level, furnace negative pressure) within safe ranges, preventing cascading failures such as boiler flameout and turbine overspeed caused by parameter malfunctions. It also reduces unplanned unit shutdowns and prevents equipment damage and the escalation of accidents.

[0036] Reduce start-up and shutdown costs and extend equipment life: By maintaining unit operation without interruption through the RB function, the complex process of shutdown and restart is eliminated, saving significant amounts of start-up fuel, shortening response time, and reducing start-up and shutdown costs. Furthermore, it avoids the impact on equipment caused by non-shutdown or emergency shutdowns (such as sudden thermal stress changes and increased mechanical wear), reducing equipment losses and extending the service life of main equipment such as boilers and turbines, as well as auxiliary equipment.

[0037] Enhancing grid support capabilities: After the RB (Resistant Power Controller) trips, the generating unit can operate stably under lower loads, maintain connection with the grid, and continuously supply power to the grid. Once the fault is cleared, the load can be quickly increased to restore normal output, enhancing the resilience of the grid during faults, helping the grid maintain frequency and voltage stability, and improving the overall reliability and support capabilities of the grid.

[0038] In summary, the intelligentization of the RB function in the operation of thermal power units involves using "smart means" such as data acquisition, intelligent algorithms, and automatic control to replace traditional manual judgment and operation. This allows the unit to automatically, accurately, and adaptably reduce the load quickly when encountering auxiliary machine failures, ensuring unit safety, coordinating with the power grid, and self-optimizing. It is a key link in the intelligent operation and maintenance and intelligent dispatch of thermal power units, deeply integrating "emergency protection" and "intelligent control".

[0039] However, the inventors discovered that in the intelligent application of the RB function, if the design of the air supply system structure is not well considered, it can also have adverse effects. For example, in some specially designed units, the air volume at the primary air fan inlet is derived from the diversion of the air volume at the outlet of the air supply fan. This means that if the air supply fan RB occurs, the air inlet of the primary air fan on the same side will be cut off. Furthermore, if the unit does not respond in time, the air supply fan RB will cause the primary air fan to surge, the furnace negative pressure to become unstable, and in severe cases, the furnace to extinguish and the entire flue gas system to trip. This will pose a significant threat to the frequency stability and overall security of the power grid.

[0040] Based on the above considerations, in order to ensure the safe and stable operation of the unit and the power grid, for such a specifically designed unit, this application provides an improved air supply control device, such as a control device applied to the RB condition of the blower. The air supply system structure shown by this device includes: a first blower 11 and a second blower 12, a first primary air fan 21 and a second primary air fan 22, a secondary air connecting valve 31 and a primary air main pipe connecting valve 32, a first air preheater 41 and a second air preheater 42, and a furnace 5. Valves are provided as needed on the pipes connecting different equipment for controlling and regulating airflow. (In conjunction with...) Figure 1 As shown, the connections between these devices include the following:

[0041] The outlet of the first blower 11 is divided into two paths, including a first branch and a second branch; the first branch is connected to the inlet of the first primary air blower 21 through a pipeline to provide air source for the first primary air blower 21; the second branch is connected to the inlet of the first air preheater 41 through a pipeline.

[0042] The outlet of the first primary air fan 21 is connected to the inlet of the first air preheater 41 through a pipeline. The air pressurized by the first primary air fan 21 is delivered to the first air preheater 41 for heat exchange and to increase the air temperature. The outlet of the first air preheater 41 sends the heated air directly into the furnace 5 through a pipeline to provide hot air for combustion in the furnace 5 and promote fuel combustion.

[0043] The outlet of the second blower 12 is divided into two paths, including the third branch and the fourth branch; the third branch is connected to the inlet of the second primary air blower 22 through a pipeline to provide air source for the second primary air blower 22; the fourth branch is connected to the inlet of the second air preheater 42 through a pipeline.

[0044] The outlet of the second primary air fan 22 is connected to the inlet of the second air preheater 42 via a pipeline. Air pressurized by the second primary air fan 22 is delivered to the second air preheater 42 for heat exchange, increasing the air temperature. The outlet of the second air preheater 42 directly supplies the heated air into the furnace 5 via a pipeline, providing hot air for combustion within the furnace and promoting fuel combustion. For example, the first blower 11 and the second blower 12 can be, but are not limited to, axial flow fans.

[0045] A secondary air connecting door 31 is provided between the connecting pipes of the first blower 11 and the second blower 12, and a primary air main pipe connecting door 32 is provided between the connecting pipes of the first primary air blower 21 and the second primary air blower 22. Both the secondary air connecting door 31 and the primary air main pipe connecting door 32 are electric doors that can complete the full opening / closing operation in a very short time (such as within 10 seconds).

[0046] It should be noted that, as in the embodiments of this application, the terms "first", "second", "third" and "fourth" are used as identifiers to distinguish different devices or branches, and there is no ambiguity in the order of these terms.

[0047] In thermal power units, the forced draft fan supplies secondary air to the boiler's combustion chamber (furnace) to provide sufficient combustion air for fuel combustion, ensuring that fuel (such as coal) burns completely in the furnace, improving combustion efficiency, and participating in regulating the combustion atmosphere in the furnace (such as oxygen distribution), thus affecting combustion stability and pollutant generation (such as controlling NOx emissions). The primary air fan supplies primary air to the boiler's pulverizing system and burners. In pulverized coal boilers, the primary air is responsible for drying the pulverized coal ground by the coal mill and conveying it to the burner, forming a pulverized coal airflow that is injected into the furnace for combustion. The velocity and volume of the primary air directly affect the ignition characteristics and combustion stability of the pulverized coal (for example, too low a velocity can easily lead to pulverized coal deposition and blockage, while too high a velocity will delay ignition).

[0048] In summary, the forced draft fan is the "oxygen supplier" for combustion in thermal power units, responsible for providing sufficient combustion air to the furnace to ensure combustion efficiency and stability. The primary air fan is the "transport link" for pulverized coal combustion, focusing on safely and stably delivering pulverized coal to the burner. It is a key piece of equipment unique to pulverized coal boilers. The secondary air from the forced draft fan and the primary air from the primary air fan mix in the furnace to complete the combustion process together, and neither can be dispensed with.

[0049] like Figure 1 As shown, for a specific design unit (the primary air fan inlet air volume is derived from the split of the forced draft fan outlet air volume), this application embodiment provides a corresponding forced draft control device including: identical equipment operating conditions on both sides, and in each side equipment operating condition, the forced draft fan outlet is divided into two paths. One branch is connected to the primary air fan inlet via a pipeline, and the primary air fan outlet is connected to the air preheater inlet via a pipeline, delivering the air pressurized by the primary air fan to the air preheater for heat exchange and to increase the air temperature. The air preheater outlet delivers the heated air directly into the furnace via a pipeline to provide hot air for combustion in the furnace and promote fuel combustion; the other branch is connected to the air preheater inlet via a pipeline; and a secondary air connecting door is provided between the two forced draft fans, and a primary air main pipe connecting door is provided between the two primary air fans.

[0050] exist Figure 1 When each side of the equipment is operating normally (e.g., the supply fan and primary air fan are running normally), both connecting doors are closed. Under these normal operating conditions, for each supply fan, air first enters the supply fan, which initially pressurizes the air. The air after being pressurized by the supply fan ( Figure 1The pipeline connection (reflecting the diversion path) includes: a portion of the air is diverted through the pipeline to the primary air fan, where it is further pressurized and then sent to the air preheater. In the air preheater, the air exchanges heat with the heat medium (usually hot flue gas), increasing its temperature. The preheated primary air then flows out of the air preheater and is finally sent into the furnace to provide the necessary air for the combustion process. The other portion of the air sent out by the blower passes through the air preheater and is then used as secondary air or for other purposes to enter the furnace and assist the combustion process.

[0051] However, if the blower on either side of the equipment malfunctions (e.g., trips), both connecting doors will be triggered to open rapidly (typically within 10 seconds) to ensure sufficient airflow and stabilize the furnace negative pressure. For example, according to... Figure 1 The air supply control device shown in this application provides a control method applied to the RB operating condition of the air supply fan, such as... Figure 2 The specific implementation steps include the following:

[0052] 101. When the first blower fails, the first blower RB triggers the electric door at the outlet of the first blower to close, and triggers the secondary air connecting door and the primary air main pipe connecting door to open fully.

[0053] 102. During the process of the second blower supplying air to the second primary air fan and the second air preheater, the air is diverted to the first primary air fan and the first air preheater through the secondary air connecting door and the primary air main pipe connecting door to ensure sufficient air intake and stabilize the negative pressure in the furnace.

[0054] During normal operation of a thermal power unit, in each side of the equipment operating condition, the forced draft fan and the primary air fan respectively bear the corresponding load to maintain the stable operation of the entire system. Furthermore, the operating principles of the equipment on both sides are the same; therefore, for example:

[0055] When the second blower fails, the second blower RB triggers the electric door at the outlet of the second blower to close, and triggers the secondary air connection door and the primary air main pipe connection door to open fully; during the process of the first blower supplying air to the first primary air fan and the first air preheater respectively, the air is diverted to the second primary air fan and the second air preheater through the secondary air connection door and the primary air main pipe connection door to ensure sufficient air intake to stabilize the negative pressure in the furnace.

[0056] Below, to avoid going into detail about the working principles of the equipment on both sides, we will refer to, for example... Figure 1 The air supply control device shown in this application example illustrates the control method applied to the air supply fan RB under the condition of equipment failure on one side (such as 101-102).

[0057] like Figure 1"When the first blower fails," for example, when the first blower trips due to a fault, the first blower RB will trigger the closing of the electric door at the outlet of the first blower. At the same time, it will trigger the rapid full opening of the secondary air connection door between the first and second blowers, as well as the rapid full opening of the primary air main pipe connection door between the first and second primary air fans. This "rapid full opening" generally occurs within 10 seconds. The second blower on the other side of the equipment can supplement air to the faulty side pipe through the secondary air connection door between the two blowers, ensuring sufficient secondary air supply. In addition, the second primary air fan on the other side of the equipment can increase its output through the primary air main pipe connection door, ensuring a stable supply of primary air. By using the rapid full opening control of these two connection doors, the total air supply to the furnace is ultimately kept basically stable, ensuring that the combustion process can continue normally and avoiding serious accidents such as combustion deterioration or even fire extinguishing caused by a blower failure on one side of the equipment.

[0058] In some modified embodiments, such as Figure 1 Based on the air supply control device shown, this application embodiment further adds corresponding feedforward processing modules to the first primary air fan and the second primary air fan respectively. That is, each primary air fan is provided with a corresponding feedforward processing module. In this application embodiment, it is possible, but not limited to, encapsulating some physical components to construct a physical module with feedforward processing function, and in this application embodiment, it is defined as "feedforward processing module". It should be noted that this application embodiment does not specifically limit the physical connection relationship between the primary air fan and its corresponding feedforward processing module.

[0059] like Figure 3 As shown, the feedforward processing module provided in this embodiment is a physical module, and its internal structure includes: a monitoring submodule 61, a judgment submodule 62, a first output submodule 63, and a second output submodule 64. The working principles of these submodules are explained below as an example:

[0060] The monitoring submodule 61 is used to monitor the blower RB signal when the first blower 11 or the second blower 12 fails; the judgment submodule 62 is used to determine whether the monitoring submodule 61 has detected the blower RB signal; the first output submodule 63 is used to not control the blades of the first primary air fan 21 or the second primary air fan 22 to increase the opening degree if the judgment submodule 62 reports that the blower RB signal has not been detected; the second output submodule 64 is used to control the blades of the first primary air fan 21 or the second primary air fan 22 to increase the preset opening degree if the judgment submodule 62 reports that the blower RB signal has been detected, and the preset opening degree is a preset percentage value of the total opening degree of the blades of the first primary air fan 21 or the second primary air fan 22.

[0061] Furthermore, the second output submodule 64 is specifically used to: when the judgment submodule 62 detects the blower RB signal, control the blower RB signal to output a pulse signal with a preset duration, and control the moving blades of the first primary fan 21 or the second primary fan 22 to increase the preset opening degree within the output duration.

[0062] Among them, the RB signal output of the blower is a pulse signal with a preset duration. The preset value is set according to experience and the unit is "seconds", such as 30 seconds. Its purpose is to maintain the continuous effect of the RB signal on the opening of the primary blower blades, rather than a single trigger and then stop, so as to achieve control of the additional opening of the primary blower blades within the output duration.

[0063] Furthermore, the second output submodule 64 is specifically used to: when the pulse signal of the blower RB signal reaches the output duration, that is, when the pulse signal disappears, control the moving blades of the first primary blower 21 or the second primary blower 22 to end the additional opening operation.

[0064] In thermal power units, the coordinated control of the forced draft fan and the primary air fan is a key aspect of ensuring stable combustion in the furnace. Besides, for example... Figure 1 In addition to improving the air supply control device by adding a connecting door to each of the two blower rooms and two primary air fan rooms on both sides, this embodiment of the application also adds a feedforward processing module to the primary air fan on each side of the equipment. The purpose is to add the blower RB signal as a feedforward signal for controlling the opening of the primary air fan blades. By introducing this feedforward signal, it is possible to trigger an additional control opening of the primary air fan blades in time when the blower RB is activated, thereby increasing the output and ensuring that the air volume matches the changes in the unit load, thereby maintaining the stability of the furnace negative pressure.

[0065] Since the working principle of the feedforward processing module is the same in both equipment operating conditions, to avoid redundancy, the following explanation uses the operating condition of one equipment as an example to illustrate the working principle of the feedforward processing module corresponding to the first primary air fan. This application embodiment provides a specific implementation method for a feedforward control strategy, such as... Figure 4 It includes the following steps:

[0066] 201. When the first blower fails, based on the feedforward processing module corresponding to the first primary blower, the blower RB signal corresponding to the first blower is monitored, and the blower RB signal output is a pulse signal with a preset duration.

[0067] In thermal power units, there are usually set RB (Resistant Draft) trigger conditions. When both blowers on both sides of the unit are operating and the unit load exceeds the load capacity of a single blower (e.g., more than 50% of the unit load), and one blower trips due to a fault, the RB function will be triggered. Once the RB function is triggered, the control system will automatically and quickly reduce the load, lowering the unit load to the target load value that the still-operating auxiliary equipment (such as the blower on the other side) can withstand. At the same time, other control systems of the unit will also make corresponding adjustments to ensure the stable operation of the unit.

[0068] 202. Based on the output duration of the blower RB signal, determine the holding duration corresponding to the additional opening operation of the moving blades of the first primary air blower.

[0069] The blower RB signal output is a pulse signal with a preset duration. The preset duration is set based on experience and is in seconds. Its purpose is to maintain the continuous effect of the RB signal on the blade opening of the primary blower, rather than a single trigger that stops. Thus, the control of the blade opening of the primary blower within the output duration is to add an additional preset opening.

[0070] 203. Based on the holding time, control the moving blades of the first primary air fan to add an additional preset opening degree, which is a preset percentage value of the total opening degree of the moving blades of the first primary air fan.

[0071] For example, in this embodiment of the application, the first primary fan blades are controlled to increase the preset opening by 15% of the total opening of the primary fan according to the duration of the pulse signal, and this is maintained until the pulse signal disappears.

[0072] 204. When the pulse signal of the blower RB signal reaches the output duration, control the moving blades of the first primary air blower to stop the additional opening operation.

[0073] According to 201-204, in the operating condition of one side of the equipment, the embodiment of this application sends the blower RB signal to the feedforward processing module corresponding to the primary fan, thereby adding the blower RB signal as a feedforward signal for the primary fan blade opening, which is used to trigger the control of the primary fan blade to increase the preset opening, thereby achieving the control of the primary fan to increase the output. When this "increase the preset opening" control operation ends, the mode of continuing to control the primary fan blade opening by the original logic is restored.

[0074] It should be noted that "restoring the mode of controlling the primary wind turbine blade opening by the original logic" refers to the opening state of the primary wind turbine blades obtained by controlling the primary wind turbine blade opening according to the original conventional control strategy during the normal operation of the thermal power unit.

[0075] In the normal operation of thermal power units, the conventional control strategies for the primary air turbine blade opening include: PID control (PID is an abbreviation for Proportional, Integral, and Derivative), air preheater RB control, and control based on bias settings set by operators. Among them, PID control adjusts the primary air turbine blade opening in real time based on the difference between the primary air pressure setpoint and the actual primary air pressure; air preheater RB control triggers the corresponding primary air turbine blade opening variable after processing based on the unit load selection logic when the air preheater RB is activated, thereby affecting the control of the primary air turbine blade opening; and control based on bias settings set by operators involves manual intervention in the control of the primary air turbine blade opening.

[0076] However, the embodiments provided in this application, such as 201-204, differ from the conventional control strategies described above. They are equivalent to using the feedforward processing module corresponding to the primary air fan to add a feedforward control strategy. When the blower RB is activated, the blades of the primary air fan are controlled to increase their opening in a timely manner. In addition to the conventional control of the blades of the primary air fan achieved by the conventional strategy described above, the primary air fan is controlled to increase its output to provide additional primary air volume. Combined with the control methods described in 101-102, and in cooperation with the rapid full opening of the connecting door, sufficient air intake is ultimately ensured, resulting in stable negative pressure in the furnace.

[0077] like Figure 5 This application provides a schematic diagram of the primary wind turbine blade control logic. Figure 5 The diagram illustrates the control components corresponding to both the conventional control strategy and the newly added feedforward control strategy. The control component corresponding to the newly added feedforward control strategy is shown below. Figure 5 The section highlighted by the dashed line will be explained in detail below.

[0078] like Figure 5 The part selected by the dashed box in the middle, where "A" is a manually set value, such as "15", thus representing the percentage value by which the primary fan blade opening is increased by controlling "A", such as "15%"; "T" represents the judgment mechanism triggered by the pulse of the blower RB signal; "Y" means that if the judgment mechanism is met, the control command "control the primary fan blade opening by increasing it by 'A'" is output; "N" means that if the judgment mechanism is not met, the control command "do not control the primary fan blade opening by increasing it by 'A'" is output.

[0079] Combining the conventional control strategy and the newly added feedforward control strategy mentioned above, the corresponding control method is as follows: During the normal operation of the thermal power unit, and in the daily process of controlling the primary air blower blade opening according to the conventional control strategy, if the blower RB (rapid load reduction) on one side of the equipment operates, the blower RB signal enters the feedforward processing module corresponding to the primary air blower, which is equivalent to triggering the feedforward signal for the control of the primary air blower blades, controlling the primary air blower to increase the blade opening by an additional amount to increase the output, such as 201-204. However, when this "additional increase in blade opening" ends, the control work of the newly added feedforward control strategy ends, and the original logic (such as...) returns to normal. Figure 5 The conventional control strategy shown continues to control the blade opening of the primary air fan.

[0080] In summary, the embodiments of this application utilize the working principle of a feedforward processing module. Furthermore, in addressing the blower RB, a new feedforward control strategy is provided, thereby contributing to the safe and stable operation of thermal power units and the power grid.

[0081] Below, in conjunction with, for example Figure 1 and Figure 2 The constructed air supply control device improves the air supply structure of this application embodiment by adding two connecting doors (such as...). Figure 1 The system includes secondary air connection gates and primary air main pipe connection gates, as well as an added feedforward processing module, enabling features such as... Figure 2 and Figure 4 The overall control method shown below will be illustrated using the following example scenario, taking the failure of the first blower on one side of the equipment as an example.

[0082] Step 1: When the first blower trips, the first blower RB triggers the closing of the electric door at the outlet of the first blower, and controls the rapid full opening of the secondary air connecting door between the two blowers and the rapid full opening of the primary air main pipe connecting door between the two primary blowers on both sides.

[0083] Step 2: The air from the outlet of the second blower is partially diverted and reaches the inlet of the first air preheater and the first primary air blower through the secondary air connecting door between the two blowers.

[0084] Step 3: The outlet air of the second primary air fan is diverted to the first air preheater through the connecting valve of the primary air main duct between the two primary air fans;

[0085] Step 4: Using the feedforward processing module corresponding to the first primary air fan, monitor and acquire the blower RB signal corresponding to the first blower. Since the blower RB signal output is a pulse signal with a preset duration (e.g., 30 seconds), control the moving blades of the first primary air fan to increase the preset opening degree within 30 seconds. For example, the preset opening degree is 15% of the total opening degree of the first primary air fan, in order to supplement the air intake and balance the air pressure.

[0086] Step 5: After a 30-second pulse, end the operation of "adding a preset opening to the blades of the first primary air fan" and continue to control the blade opening of the first primary air fan by other conventional control strategies in the thermal power unit.

[0087] As shown in steps 1-5 above, the primary fan blade control process is illustrated using the tripping of the first blower as an example. When the unit is running normally, the blower RB signal is not triggered. Combined with... Figure 5 The control section selected by the dashed box implements the feedforward control strategy using the feedforward processing module, including: when both blowers are working normally, there is no blower RB signal, the T selection block outputs the N-side setpoint 0, and the first primary blower blade opening is controlled by the original logic; when the first blower trips, the blower RB signal is triggered. Since the blower RB signal output duration is a preset value (e.g., 30 seconds) pulse signal, and when the blower RB signal is triggered, the T selection block outputs the Y-side to obtain A (A is a preset bias, such as 15), that is, the first primary blower blade opening is controlled by an additional 15% of the total opening on the existing basis to ensure the stability of the air preheater inlet air pressure and furnace negative pressure; after the blower RB signal is issued for 30 seconds, the pulse signal disappears, the T selection block outputs the N-side setpoint 0, and the first primary blower blade opening continues to be controlled by other conventional control strategies in the thermal power unit.

[0088] In summary, the control device and method provided in this application for the operation of the blower RB condition include a connecting door between the two blower rooms and the two primary air fan rooms on each side of the equipment operation. When the blower RB is in operation on one side of the equipment, the connecting door is fully opened by triggering it to ensure sufficient air intake to stabilize the furnace negative pressure, thereby maintaining the stability of the primary air fan pressure and the furnace negative pressure. Furthermore, a feedforward processing module is provided for the primary air fan on each side of the equipment operation to add the blower RB signal to the primary air fan blades. The feedforward signal for the opening control enables timely triggering of additional action on the primary air blower blades to increase output when the blower RB is activated. This is equivalent to adding a feedforward control strategy for the opening of the primary air blower blades. Based on the above improvements to the control device, a control method that coordinates the fully open connecting gate and the newly added feedforward control strategy is realized. This greatly avoids tripping of the air preheater RB and the entire flue gas system, maintains stable furnace negative pressure, ensures the safety of the unit and the power grid, and improves the efficiency and economy of the generator unit operation.

[0089] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0090] 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 embodied 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.

[0091] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A control device applied to the RB operating condition of a blower, characterized in that, The device includes: a first blower and a second blower, a first primary air fan and a second primary air fan, a secondary air connecting valve and a primary air main pipe connecting valve, a first air preheater and a second air preheater, and a furnace; wherein, valves are provided as needed on the pipes connecting different equipment to control and regulate the airflow; The first blower outlet is divided into two paths, including a first branch and a second branch; the first branch is connected to the inlet of the first primary air blower through a pipeline to provide air source for the first primary air blower; the second branch is connected to the inlet of the first air preheater through a pipeline. The outlet of the first primary air blower is connected to the inlet of the first air preheater through a pipeline, and the air pressurized by the first primary air blower is delivered to the first air preheater for heat exchange and to increase the air temperature. The outlet of the first air preheater directly sends heated air into the furnace through a pipeline to provide hot air for combustion in the furnace and promote fuel combustion. The outlet of the second blower is divided into two paths, including a third branch and a fourth branch; the third branch is connected to the inlet of the second primary air blower through a pipeline to provide air source for the second primary air blower; the fourth branch is connected to the inlet of the second air preheater through a pipeline. The outlet of the second primary air fan is connected to the inlet of the second air preheater through a pipeline, and the air pressurized by the second primary air fan is delivered to the second air preheater for heat exchange and to increase the air temperature. The outlet of the second air preheater directly sends heated air into the furnace through a pipeline to provide hot air for combustion in the furnace and promote fuel combustion. A secondary air connecting valve is provided between the connecting pipes of the first blower and the second blower, and a primary air main pipe connecting valve is provided between the connecting pipes of the first primary air blower and the second primary air blower. When the first blower or the second blower fails, the secondary air connecting valve and the primary air main pipe connecting valve are triggered to fully open, so as to ensure sufficient air intake and stabilize the negative pressure in the furnace.

2. The apparatus according to claim 1, characterized in that, The device also includes feedforward processing modules corresponding to the first primary fan and the second primary fan, respectively. The feedforward processing module includes: a monitoring submodule, a judgment submodule, a first output submodule, and a second output submodule; The monitoring submodule is used to monitor the RB signal of the blower when the first blower or the second blower fails; The judgment submodule is used to determine whether the monitoring submodule has detected the blower RB signal; The first output submodule is configured to not control the blades of the first primary air fan or the second primary air fan to increase their opening degree if the judgment submodule reports that the blower RB signal has not been detected. The second output submodule is used to control the moving blades of the first primary air fan or the second primary air fan to increase the preset opening degree if the judgment submodule detects the RB signal of the blower. The preset opening degree is a preset percentage value of the total opening degree of the moving blades of the first primary air fan or the second primary air fan.

3. The apparatus according to claim 2, characterized in that, The second output submodule is further specifically used to: when the judgment submodule detects the blower RB signal, control the blower RB signal to output a pulse signal with a preset duration, and control the blades of the first primary fan or the second primary fan to increase the preset opening degree within the output duration.

4. The apparatus according to claim 3, characterized in that, The second output submodule is also specifically used to: when the pulse signal is emitted for the specified output duration, control the moving blades of the first primary fan or the second primary fan to stop the additional opening operation.

5. The apparatus according to any one of claims 1 to 4, characterized in that, The secondary air connecting door and the primary air main pipe connecting door are electric doors that can be fully opened or fully closed within a preset time period.

6. The apparatus according to any one of claims 1 to 4, characterized in that, The first blower and the second blower are axial flow fans.

7. A control method applied to the RB operating condition of a blower, applicable to the apparatus as described in any one of claims 1 to 6, characterized in that, The method includes: When the first blower fails, the first blower RB triggers the electric door at the outlet of the first blower to close, and triggers the secondary air connecting door and the primary air main pipe connecting door to open fully; During the process of the second blower supplying air to the second primary air fan and the second air preheater, the supplied air is diverted to the first primary air fan and the first air preheater through the secondary air connecting valve and the primary air main connecting valve, to ensure sufficient air intake and stabilize the negative pressure in the furnace; or... When the second blower fails, the second blower RB triggers the electric door at the outlet of the second blower to close, and triggers the secondary air connecting door and the primary air main pipe connecting door to open fully; During the process of the first blower supplying air to the first primary air blower and the first air preheater, the air is diverted to the second primary air blower and the second air preheater through the secondary air connecting valve and the primary air main pipe connecting valve to ensure sufficient air intake and stabilize the negative pressure in the furnace.

8. The method according to claim 7, characterized in that, When the first blower fails, the method further includes: Based on the feedforward processing module corresponding to the first primary air blower, the blower RB signal corresponding to the first blower is monitored, and the blower RB signal outputs a pulse signal with a preset duration. Based on the output duration, determine the holding duration corresponding to the additional opening operation of the moving blades of the first primary air blower; Based on the holding time, the moving blades of the first primary air fan are controlled to have an additional preset opening, wherein the preset opening is a preset percentage value of the total opening of the moving blades of the first primary air fan.

9. The method according to claim 8, characterized in that, The method further includes: After the pulse signal is emitted for the specified output duration, the operation of increasing the opening degree of the first primary air fan blades is stopped.

10. A computer program product comprising a computer program / instructions, characterized in that, When the computer instructions are executed by the processor, they implement the steps of the control method for the blower RB operating condition as described in any one of claims 7-9.

Images