Load change air volume control method and device, electronic equipment and storage medium

Abstract

The invention discloses an air quantity control method and device for load change, electronic equipment and a storage medium, relates to the technical field of control, and can determine real-time oxygen quantity deviation by combining main steam flow and an oxygen quantity set value function table containing a nonlinear mapping relation. PID regulator parameters of an oxygen quantity control loop are dynamically adjusted according to the deviation and the change rate of the load instruction, an air quantity instruction generated according to the nonlinear relation between the fuel quantity and the preset air quantity set value function table can be corrected through the change rate of the fuel quantity, and the dynamic relation between the load change rate and the oxygen quantity deviation is established; the limitation of a static PID parameter and a fixed function relation is broken through, and the technical effects of improving the boiler combustion efficiency, enhancing the stability of an air supply control system, improving the adjusting precision and guaranteeing the automatic control capability of the system in a full load section are achieved.

Description

Technical Field

[0001] This disclosure relates to the field of control technology, and in particular to a method and apparatus for controlling air volume under load variations, electronic equipment, and storage medium. Background Technology

[0002] Boiler air supply control systems, as a core technology for combustion optimization in thermal power plants, are widely used in unit load regulation and emission control. Among related technologies, an air supply control system based on closed-loop oxygen correction has been constructed through function mapping of main steam flow and oxygen setpoint, and the coordinated operation of PID controllers and frequency converters.

[0003] Existing technologies directly use static PID parameters and fixed function relationships without establishing a dynamic correlation with load change rate and oxygen content deviation. This may lead to decreased combustion efficiency and insufficient system stability, affecting adjustment accuracy and restricting the system's automatic control capability across the entire load range. Summary of the Invention

[0004] This disclosure provides a method, apparatus, electronic device, and storage medium for controlling airflow under varying load conditions. Its main purpose is to address the problems of decreased combustion efficiency and insufficient system stability, which affect adjustment accuracy and limit the system's automatic control capability across the entire load range.

[0005] According to a first aspect of this disclosure, a method for controlling airflow under load variation is provided, comprising: The boiler main steam flow rate is obtained and the real-time oxygen deviation is determined based on a preset oxygen setpoint function table; wherein, the oxygen setpoint function table contains a non-linear mapping relationship between the main steam flow rate and the oxygen percentage. The proportional and integral coefficients of the PID controller in the oxygen control loop are dynamically adjusted based on the real-time oxygen deviation and the rate of change of the load command. The fuel quantity change rate is calculated to correct the air volume command, which is generated by the nonlinear relationship between the fuel quantity and a preset air volume setpoint function table; The frequency conversion control signal for the blower is generated based on the adjusted PID parameters and the corrected air volume command.

[0006] Optionally, obtaining the boiler main steam flow rate and determining the real-time oxygen deviation based on a preset oxygen setpoint function table includes: Determine the nonlinear mapping relationship between main steam flow rate and oxygen percentage; The lookup results are interpolated and corrected based on the oxygen setpoint function curve. When the main steam flow rate is within the preset value range, the target oxygen setpoint is calculated using a linear interpolation algorithm.

[0007] Optionally, the calculation of the fuel quantity change rate to correct the air volume command includes: Determine the nonlinear mapping relationship between fuel quantity and air volume. The air volume command is graded according to the control logic diagram. When the rate of change of fuel quantity exceeds the first preset rate of change, the differential compensation amount is calculated based on the preset formula.

[0008] Optionally, generating the frequency conversion control signal for the blower based on the adjusted PID parameters and the corrected air volume command includes: Set the minimum airflow protection threshold for the frequency converter control signal, and switch to the minimum airflow protection mode when the corrected airflow command is lower than the threshold. A rate limit is applied to the frequency converter control signal. When the rate of change of the oxygen quantity operator bias exceeds the second preset change threshold, a rate constraint is applied.

[0009] Optionally, the method further includes: When the blower is switched to manual mode, the current inverter control signal remains unchanged. When the blower switches to automatic mode, the command transition is achieved through offset correction.

[0010] According to a second aspect of this disclosure, a load-varying airflow control device is provided, comprising: The acquisition unit is used to acquire the main steam flow rate of the boiler and determine the real-time oxygen deviation based on a preset oxygen setpoint function table; wherein, the oxygen setpoint function table contains a non-linear mapping relationship between the main steam flow rate and the oxygen percentage. The adjustment unit is used to dynamically adjust the proportional coefficient and integral coefficient of the PID controller of the oxygen control loop according to the real-time oxygen deviation and the load command change rate. The calculation unit is used to calculate the rate of change of fuel quantity to correct the air volume command, which is generated by the nonlinear relationship between fuel quantity and a preset air volume setpoint function table; The generation unit is used to generate the frequency conversion control signal for the blower based on the adjusted PID parameters and the corrected air volume command.

[0011] Optionally, the acquisition unit is further configured to: Determine the nonlinear mapping relationship between main steam flow rate and oxygen percentage; The lookup results are interpolated and corrected based on the oxygen setpoint function curve. When the main steam flow rate is within the preset value range, the target oxygen setpoint is calculated using a linear interpolation algorithm.

[0012] Optionally, the computing unit is further configured to: Determine the nonlinear mapping relationship between fuel quantity and air volume. The air volume command is graded according to the control logic diagram. When the rate of change of fuel quantity exceeds the first preset rate of change, the differential compensation amount is calculated based on the preset formula.

[0013] Optionally, the generation unit is further configured to: Set the minimum airflow protection threshold for the frequency converter control signal, and switch to the minimum airflow protection mode when the corrected airflow command is lower than the threshold. A rate limit is applied to the frequency converter control signal. When the rate of change of the oxygen quantity operator bias exceeds the second preset change threshold, a rate constraint is applied.

[0014] Optionally, the device further includes: The control unit is used to maintain the current inverter control signal unchanged when the blower is switched to manual mode. The control unit is also used to achieve a smooth transition of commands by means of an offset correction amount when the blower switches to automatic mode.

[0015] According to a third aspect of this disclosure, an electronic device is provided, comprising: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method described in the first aspect above.

[0016] According to a fourth aspect of this disclosure, a non-transitory computer-readable storage medium is provided storing computer instructions, wherein the computer instructions are configured to cause the computer to perform the method described in the first aspect above.

[0017] According to a fifth aspect of this disclosure, a computer program product is provided, comprising a computer program that, when executed by a processor, implements the method described in the first aspect above.

[0018] The airflow control method, apparatus, electronic equipment, and storage medium for load changes disclosed herein, through this application, can determine the real-time oxygen deviation by combining the main steam flow with an oxygen setpoint function table containing a nonlinear mapping relationship, and dynamically adjust the PID regulator parameters of the oxygen control loop according to the deviation and the load command change rate. Furthermore, it can correct the airflow command generated by the nonlinear relationship between the fuel quantity and the preset airflow setpoint function table through the fuel quantity change rate, establishing a dynamic correlation with the load change rate and oxygen deviation. This breaks the limitations of static PID parameters and fixed function relationships. Therefore, it can solve the technical problems of decreased combustion efficiency, insufficient system stability, and poor adjustment accuracy caused by the use of static PID parameters and fixed function relationships and the lack of dynamic correlation in existing technologies, thus restricting the automatic control capability of the system across the entire load range. This achieves the technical effects of improving boiler combustion efficiency, enhancing the stability of the air supply control system, improving adjustment accuracy, and ensuring the automatic control capability of the system across the entire load range.

[0019] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0020] The accompanying drawings are provided to better understand this solution and do not constitute a limitation of this disclosure. Wherein: Figure 1 A schematic flowchart illustrating a load-varying airflow control method provided in an embodiment of this disclosure; Figure 2 A schematic diagram of the structure of an air volume control device for load variation provided in an embodiment of this disclosure; Figure 3 A schematic diagram of another load-varying airflow control device provided in an embodiment of this disclosure; Figure 4 A schematic block diagram of an example electronic device provided for embodiments of this disclosure. Detailed Implementation

[0021] The exemplary embodiments of this disclosure are described below with reference to the accompanying drawings, including various details of the embodiments to aid understanding, and should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this disclosure. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0022] The following description, with reference to the accompanying drawings, describes a method, apparatus, electronic device, and storage medium for controlling airflow under load variations according to embodiments of the present disclosure.

[0023] Figure 1 This is a schematic flowchart of a load-varying airflow control method provided in an embodiment of the present disclosure.

[0024] like Figure 1 As shown, the method includes the following steps: Step 101: Obtain the main steam flow rate of the boiler and determine the real-time oxygen deviation based on the preset oxygen setpoint function table; wherein, the oxygen setpoint function table contains a non-linear mapping relationship between the main steam flow rate and the oxygen percentage. The boiler's main steam flow rate is acquired, and the real-time oxygen deviation is determined based on a preset oxygen setpoint function table. The main steam flow rate is a core parameter reflecting the boiler's current load status, directly indicating the energy output from fuel combustion. Its value is closely related to the air demand for boiler combustion and is typically collected in real-time by dedicated measuring equipment within the boiler operating system to ensure accurate reflection of the boiler's actual operating load. The preset oxygen setpoint function table is pre-defined based on the boiler's combustion characteristics, efficiency requirements, and environmental standards under different load conditions. The core of this function table lies in establishing a non-linear mapping relationship between the main steam flow rate and the oxygen percentage. This non-linear relationship stems from the fact that the optimal oxygen demand for fuel combustion does not increase or decrease linearly with load changes but must be determined comprehensively by considering factors such as combustion reaction efficiency and flue gas pollutant generation patterns to ensure the boiler operates in an optimal combustion state under different loads.

[0025] When determining the real-time oxygen deviation, the target oxygen percentage is first obtained by matching the current main steam flow of the boiler from the preset oxygen setpoint function table. Then, the difference between the target oxygen percentage and the actual detected oxygen content of the flue gas at the tail of the boiler is calculated. The final result is the real-time oxygen deviation, which will provide a key basis for the precise adjustment of the subsequent air supply control.

[0026] Step 102: Dynamically adjust the proportional coefficient and integral coefficient of the PID controller of the oxygen control loop according to the real-time oxygen deviation and the load command change rate. In the operation of the air supply control system, step 102 involves dynamically adjusting the proportional and integral coefficients of the PID controller in the oxygen control loop based on the real-time oxygen deviation and the rate of change of the load command. The oxygen control loop is the core control component ensuring that the oxygen content of the flue gas in the boiler tail flue meets combustion requirements. It indirectly affects the total air volume entering the furnace by outputting a regulation signal through the PID controller. The proportional coefficient of the PID controller primarily determines the control system's response speed to deviations, while the integral coefficient is mainly responsible for eliminating the system's steady-state error. A proper match between the two is crucial for ensuring the accuracy of oxygen control.

[0027] Real-time oxygen deviation is the difference between the target oxygen percentage and the actual flue gas oxygen content calculated in the previous steps. Its magnitude directly reflects the degree to which the current oxygen content deviates from the ideal state. The load command change rate reflects the trend of the boiler's current load change; rapid increases or decreases in load will cause changes in the oxygen required for combustion. Based on these two parameters, dynamically adjusting the proportional and integral coefficients allows the PID controller to maintain optimal control performance under different operating conditions. For example, when the real-time oxygen deviation is large or the load command change rate is high, the proportional coefficient is appropriately adjusted to speed up the response, while the integral coefficient is optimized to avoid over-adjustment. When the deviation is small or the load tends to be stable, the coefficients are adjusted accordingly to improve control stability, ultimately ensuring that the oxygen control loop can adapt to the changing load conditions of each load segment and maintain the flue gas oxygen content within a reasonable range.

[0028] Step 103: Calculate the fuel quantity change rate to correct the air volume command. The air volume command is generated by the nonlinear relationship between the fuel quantity and the preset air volume setpoint function table. The airflow command is generated by the non-linear relationship between fuel quantity and a preset airflow setpoint function table. Fuel quantity is a core parameter reflecting the scale of material input into the boiler combustion chamber. Its value is directly related to the basic volume of air required for combustion reaction in the furnace. It needs to be collected in real time by a dedicated detection component of the boiler fuel supply system to ensure accurate matching of the air demand benchmark under the current combustion conditions. The preset airflow setpoint function table is pre-defined based on the boiler's combustion efficiency characteristics under different fuel inputs, pollutant generation control requirements, and equipment safety operation thresholds. The non-linear relationship between fuel quantity and airflow in the table stems from the fact that the optimal airflow does not increase or decrease linearly with changes in fuel quantity. For example, in the low fuel quantity stage, a relatively higher airflow ratio needs to be maintained to ensure complete fuel combustion, while in the high fuel quantity stage, the rate of increase in airflow needs to be appropriately slowed to avoid excess airflow and energy waste, thus adapting to the high-efficiency combustion requirements under different fuel inputs.

[0029] The fuel quantity change rate is used to capture the real-time trend of fuel input changes. When the fuel quantity increases or decreases rapidly, if the air volume command is adjusted solely based on the current fuel quantity, the air volume response may lag behind the fuel change, leading to an imbalance in the air-fuel ratio within the furnace. By calculating the fuel quantity change rate to correct the air volume command, the air volume adjustment can better match the dynamic changes in the fuel quantity, ensuring a reasonable air-fuel ratio is maintained within the furnace. This provides a suitable command for the precise control of the subsequent blower, thereby ensuring the stability and economy of boiler combustion.

[0030] Step 104: Generate the frequency conversion control signal for the blower based on the adjusted PID parameters and the corrected air volume command.

[0031] In the operation of the air supply control system, step 104 generates the frequency conversion control signal for the blower based on the adjusted PID parameters and the corrected air volume command. The adjusted PID parameters are the proportional and integral coefficients of the oxygen control loop, dynamically optimized in step 102 based on the real-time oxygen deviation and the rate of change of the load command. These parameters ensure that the oxygen control can adapt to the deviation response and steady-state error elimination requirements under different operating conditions, providing control logic support for the accuracy of subsequent air volume adjustment. The corrected air volume command is generated in step 103 by combining the nonlinear relationship between the fuel quantity and the preset air volume setpoint function table, and corrected for the rate of change of the fuel quantity. It fully matches the dynamic change rhythm of the current fuel input, providing a basic air volume benchmark that meets the furnace air-coal ratio requirements for blower adjustment.

[0032] When generating the frequency converter control signal for the forced draft fan, the output of the total air volume regulator must be used as the core linkage basis. The total air volume regulator integrates the adjusted PID parameters for oxygen regulation logic and the corrected air volume command for basic air volume requirements, converting both into signal logic suitable for the frequency converter control of the forced draft fan. Simultaneously, this frequency converter control signal must adhere to the parameter constraints of the forced draft fan's automatic frequency converter operation, ensuring that the corresponding frequency converter command is within a reasonable range of 36% to 95%, and can be linked to the minimum air volume protection mechanism of the air volume command. When the corresponding air volume approaches 500 t / h, protection is triggered to prevent excessively low air volume from affecting combustion safety. The final generated frequency converter control signal for the forced draft fan can directly act on the frequency converter systems of the two forced draft fans, achieving synchronous or coordinated adjustment of the forced draft fan operating frequency, thereby precisely controlling the total air volume entering the furnace, meeting the combustion requirements under varying load conditions at different load stages of the boiler, and ensuring combustion efficiency and operational stability.

[0033] In some embodiments, obtaining the boiler main steam flow rate and determining the real-time oxygen deviation based on a preset oxygen setpoint function table includes: Determine the nonlinear mapping relationship between main steam flow rate and oxygen percentage; The lookup results are interpolated and corrected based on the oxygen setpoint function curve. When the main steam flow rate is within the preset value range, the target oxygen setpoint is calculated using a linear interpolation algorithm.

[0034] When obtaining the boiler main steam flow rate and determining the real-time oxygen deviation based on the preset oxygen setpoint function table according to claim 1, it is first necessary to determine the nonlinear mapping relationship between the main steam flow rate and the oxygen percentage. This mapping relationship is pre-constructed based on the boiler's combustion efficiency, pollutant generation patterns, and equipment operation requirements under different load conditions. Specifically, it is implemented through the oxygen setpoint function table, which covers the oxygen percentage corresponding to multiple key nodes such as the main steam flow rate from 0 to 800 t / h. For example, the oxygen is 5.1% when the main steam flow rate is 0 and 350 t / h, and drops to 4.2% when the flow rate increases to 500 t / h. Subsequently, the oxygen gradually decreases to 3.4% as the flow rate continues to increase. These data nodes together constitute the nonlinear mapping relationship between the two, which is not uniformly changing, ensuring that there is a corresponding ideal oxygen benchmark under different loads.

[0035] The lookup results need to be interpolated and corrected based on the oxygen setpoint function curve. The oxygen setpoint function curve is a visual representation of the function table data, which can more intuitively reflect the non-linear change trend of the main steam flow and the oxygen percentage. When the main steam flow in actual boiler operation falls within two preset value ranges in the oxygen setpoint function table, such as a specific value between 350t / h and 500t / h, the corresponding oxygen percentage cannot be directly obtained from the function table. Therefore, a linear interpolation algorithm is needed to calculate the target oxygen setpoint. Using the known main steam flow and corresponding oxygen at both ends of the range as a benchmark, the target oxygen corresponding to any main steam flow within the range is obtained through linear calculation. This allows the target oxygen setpoint to more accurately match the actual load changes, avoiding oxygen setpoint deviations caused by the load falling within the value gaps in the table, and thus ensuring the accuracy of real-time oxygen deviation calculation.

[0036] In some embodiments, the calculation of the fuel quantity change rate to correct the air volume command includes: Determine the nonlinear mapping relationship between fuel quantity and air volume. The air volume command is graded according to the control logic diagram. When the rate of change of fuel quantity exceeds the first preset rate of change, the differential compensation amount is calculated based on the preset formula.

[0037] When calculating the fuel quantity change rate to correct the air volume command according to the method described in claim 1, it is first necessary to determine the nonlinear mapping relationship between fuel quantity and air volume. This relationship is realized through a preset air volume setpoint function table. The function table covers different nodes of fuel quantity from 0 to 135 t / h and the corresponding air volume values. For example, when the fuel quantity is 0 and 40 t / h, the air volume is 500 t / h. When the fuel quantity reaches 60 t / h, the air volume increases to 700 t / h. As the fuel quantity continues to increase, the air volume gradually increases to 1100 t / h corresponding to 135 t / h. This nonlinear mapping is due to the difference in combustion demand under different fuel input. In the low fuel quantity stage, a higher air volume ratio is required to ensure complete fuel combustion. In the high fuel quantity stage, the increase in air volume needs to be controlled to avoid energy waste, thereby adapting to the high-efficiency combustion requirements of various fuel quantity conditions.

[0038] Next, the airflow command is graded and corrected according to the airflow control logic diagram. The airflow control logic diagram is the core basis for integrating fuel quantity changes and airflow adjustment logic. It can adjust the correction range of the airflow command in stages according to real-time fuel quantity fluctuations to ensure that the airflow adjustment matches the rhythm of combustion condition changes. When the fuel quantity change rate exceeds the first preset change rate, a differential compensation amount is calculated based on a preset formula. This compensation amount compensates for the response lag problem that may occur in the airflow command when the fuel quantity changes rapidly, avoids the imbalance of air-fuel ratio in the furnace, further optimizes the dynamic adaptability of the airflow command, and lays the foundation for the subsequent generation of accurate blower frequency conversion control signals.

[0039] In some embodiments, generating the blower frequency conversion control signal based on the adjusted PID parameters and the corrected air volume command includes: Set the minimum airflow protection threshold for the frequency converter control signal, and switch to the minimum airflow protection mode when the corrected airflow command is lower than the threshold. A rate limit is applied to the frequency converter control signal. When the rate of change of the oxygen quantity operator bias exceeds the second preset change threshold, a rate constraint is applied.

[0040] When generating the blower frequency converter control signal based on the adjusted PID parameters and the corrected air volume command according to claim 1, a minimum air volume protection threshold for the frequency converter control signal must first be set. This threshold is a key parameter preset to avoid insufficient air volume in the furnace, incomplete fuel combustion, or safety hazards caused by the corrected air volume command being too low. It needs to match the basic air volume requirements for safe operation of the boiler at each load segment. When the corrected air volume command is lower than this threshold, the system will automatically switch to the minimum air volume protection mode. At this time, the blower frequency converter control signal will be output based on the air volume corresponding to the threshold, ensuring that the total air volume entering the furnace is always maintained within the safe operating range, providing a basic guarantee for stable boiler combustion.

[0041] A rate limit needs to be applied to the frequency converter control signal, primarily targeting changes in the oxygen operator bias. The oxygen operator bias can be fine-tuned according to actual combustion conditions, but if the rate of change is too rapid, it can cause frequent fluctuations in the frequency converter control signal, thus affecting the stability of the blower operation. Therefore, when the rate of change of the oxygen operator bias exceeds a second preset threshold, the system automatically applies a rate constraint, ensuring a smooth rate of change in the bias. This guarantees a gradual output rhythm of the frequency converter control signal, preventing frequent start-stops or large speed fluctuations in the blower due to sudden changes in commands. Combined with the precise control of oxygen by the adjusted PID parameters and the adaptability of the corrected airflow commands, the overall stability and reliability of the air supply control system are ultimately guaranteed.

[0042] In some embodiments, the method further includes: When the blower is switched to manual mode, the current inverter control signal remains unchanged. When the blower switches to automatic mode, the command transition is achieved through offset correction.

[0043] The method according to claim 1 further includes control logic for switching the blower mode. When the blower switches to manual mode, the current frequency converter control signal must remain unchanged. This is because manual mode switching is usually adjusted by the operator according to the on-site working conditions. If the frequency converter control signal changes abruptly at the moment of switching, it will directly cause a sudden change in the blower speed, which in turn will cause a sudden fluctuation in the total air volume entering the furnace, disrupting the stable air-coal ratio in the furnace. This may result in incomplete combustion of fuel or a sudden change in combustion intensity, affecting the boiler's operating safety and efficiency. Keeping the current signal unchanged can ensure that the total air volume supplied during the switching process remains continuous and stable, providing a smooth transition basis for the operator's manual adjustment.

[0044] When switching the blower from manual to automatic mode, a smooth transition of commands is achieved through offset correction. In manual mode, operators may have adjusted the blower's operating parameters based on actual conditions, leading to a discrepancy between the variable frequency drive (VFD) command in manual mode and the target command calculated in automatic mode based on the adjusted PID parameters and corrected airflow command. Directly switching to the target command in automatic mode would cause a step change in the command, resulting in significant fluctuations in the blower's speed. Offset correction gradually eliminates this discrepancy, allowing the VFD control signal to slowly transition from the current value in manual mode to the target value in automatic mode. This avoids airflow surges, ensures stable operation of the air supply system during the switch between the two control modes, adapts to the combustion requirements of different boiler load sections, and guarantees the stability of the overall control system.

[0045] Corresponding to the aforementioned airflow control method based on load variation, this invention also proposes an airflow control device based on load variation. Since the device embodiments of this invention correspond to the aforementioned method embodiments, details not disclosed in the device embodiments can be referred to the aforementioned method embodiments, and will not be repeated here.

[0046] Figure 2 This is a schematic diagram of the structure of a load-varying airflow control device provided in an embodiment of the present disclosure, as shown below. Figure 2 As shown, it includes: The acquisition unit 21 is used to acquire the main steam flow rate of the boiler and determine the real-time oxygen deviation based on a preset oxygen setpoint function table; wherein, the oxygen setpoint function table contains a non-linear mapping relationship between the main steam flow rate and the oxygen percentage. Adjustment unit 22 is used to dynamically adjust the proportional coefficient and integral coefficient of the PID controller of the oxygen control loop according to the real-time oxygen deviation and the load command change rate. Calculation unit 23 is used to calculate the rate of change of fuel quantity to correct the air volume command, wherein the air volume command is generated by the nonlinear relationship between fuel quantity and a preset air volume setpoint function table; The generation unit 24 is used to generate a frequency conversion control signal for the blower based on the adjusted PID parameters and the corrected air volume command.

[0047] Furthermore, in one possible implementation of this disclosure, the acquisition unit 21 is further configured to: Determine the nonlinear mapping relationship between main steam flow rate and oxygen percentage; The lookup results are interpolated and corrected based on the oxygen setpoint function curve. When the main steam flow rate is within the preset value range, the target oxygen setpoint is calculated using a linear interpolation algorithm.

[0048] Furthermore, in one possible implementation of this disclosure, the computing unit 23 is further configured to: Determine the nonlinear mapping relationship between fuel quantity and air volume. The air volume command is graded according to the control logic diagram. When the rate of change of fuel quantity exceeds the first preset rate of change, the differential compensation amount is calculated based on the preset formula.

[0049] Furthermore, in one possible implementation of this disclosure embodiment, the generation unit 24 is further configured to: Set the minimum airflow protection threshold for the frequency converter control signal, and switch to the minimum airflow protection mode when the corrected airflow command is lower than the threshold. A rate limit is applied to the frequency converter control signal. When the rate of change of the oxygen quantity operator bias exceeds the second preset change threshold, a rate constraint is applied.

[0050] Furthermore, in one possible implementation of the embodiments of this disclosure, such as Figure 3 As shown, the device further includes: Control unit 25 is used to maintain the current frequency converter control signal unchanged when the blower is switched to manual mode. The control unit 25 is also configured to achieve a smooth transition of commands by means of an offset correction amount when the blower switches to automatic mode.

[0051] It should be noted that the foregoing explanation of the method embodiments also applies to the apparatus of the embodiments of this disclosure, and the principle is the same. Therefore, the embodiments of this disclosure are not limited thereto.

[0052] According to embodiments of this disclosure, this disclosure also provides an electronic device, a readable storage medium, and a computer program product.

[0053] Figure 4 A schematic block diagram of an example electronic device 400 that can be used to implement embodiments of the present disclosure is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0054] like Figure 4 As shown, device 400 includes a computing unit 401, which can perform various appropriate actions and processes based on a computer program stored in ROM (Read-Only Memory) 402 or a computer program loaded from storage unit 408 into RAM (Random Access Memory) 403. RAM 403 may also store various programs and data required for the operation of device 400. The computing unit 401, ROM 402, and RAM 403 are interconnected via bus 404. I / O (Input / Output) interface 405 is also connected to bus 404.

[0055] Multiple components in device 400 are connected to I / O interface 405, including: input unit 406, such as keyboard, mouse, etc.; output unit 407, such as various types of monitors, speakers, etc.; storage unit 408, such as disk, optical disk, etc.; and communication unit 409, such as network card, modem, wireless transceiver, etc. Communication unit 409 allows device 400 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0056] The computing unit 401 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 401 include, but are not limited to, CPUs (Central Processing Units), GPUs (Graphics Processing Units), various special-purpose AI (Artificial Intelligence) computing chips, various computing units running machine learning model algorithms, DSPs (Digital Signal Processors), and any suitable processor, controller, microcontroller, etc. The computing unit 401 performs the various methods and processes described above, such as the airflow control method for load variations. For example, in some embodiments, the airflow control method for load variations may be implemented as a computer software program tangibly contained in a machine-readable medium, such as storage unit 408. In some embodiments, part or all of the computer program may be loaded and / or installed on device 400 via ROM 402 and / or communication unit 409. When the computer program is loaded into RAM 403 and executed by the computing unit 401, one or more steps of the methods described above may be performed. Alternatively, in other embodiments, the computing unit 401 may be configured to perform the aforementioned airflow control method for load changes by any other suitable means (e.g., by means of firmware).

[0057] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, FPGAs (Field Programmable Gate Arrays), ASICs (Application-Specific Integrated Circuits), ASSPs (Application-Specific Standard Products), SOCs (System-on-Chips), CPLDs (Complex Programmable Logic Devices), computer hardware, firmware, software, and / or combinations thereof. These various implementations may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0058] The program code used to implement the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0059] In the context of this disclosure, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, RAM, ROM, EPROM (Electrically Programmable Read-Only Memory) or flash memory, optical fiber, CD-ROM (Compact Disc Read-Only Memory), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0060] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for displaying information to the user (e.g., a CRT (Cathode-Ray Tube) or LCD (Liquid Crystal Display) monitor); and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0061] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include LANs (Local Area Networks), WANs (Wide Area Networks), the Internet, and blockchain networks.

[0062] Computer systems can include clients and servers. Clients and servers are generally geographically separated and typically interact via communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. A server can be a cloud server, also known as a cloud computing server or cloud host, a hosting product within the cloud computing service system that addresses the shortcomings of traditional physical hosts and VPS (Virtual Private Server) services, such as high management difficulty and weak business scalability. Servers can also be servers for distributed systems or servers incorporating blockchain technology.

[0063] It's important to note that artificial intelligence (AI) is the study of enabling computers to simulate certain human thought processes and intelligent behaviors (such as learning, reasoning, thinking, and planning). It encompasses both hardware and software technologies. AI hardware technologies generally include sensors, dedicated AI chips, cloud computing, distributed storage, and big data processing. AI software technologies primarily include computer vision, speech recognition, natural language processing, machine learning / deep learning, big data processing, and knowledge graph technologies.

[0064] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this disclosure can be achieved, and this is not limited herein.

[0065] The specific embodiments described above do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A method of airflow control for varying loads, characterized by, The method comprises: obtaining the main steam flow of the boiler and determining the real-time oxygen deviation based on a preset oxygen set value function table, wherein the oxygen set value function table comprises a nonlinear mapping relationship between the main steam flow and the oxygen percentage; dynamically adjusting the proportional coefficient and the integral coefficient of the PID regulator of the oxygen control loop according to the real-time oxygen deviation and the load instruction change rate; correcting the air volume instruction by the fuel quantity change rate, wherein the air volume instruction is generated by the nonlinear relationship between the fuel quantity and a preset air volume set value function table; generating the variable frequency control signal of the forced draught fan based on the adjusted PID parameters and the corrected air volume instruction.

2. The method of claim 1, wherein, The method of obtaining the main steam flow of the boiler and determining the real-time oxygen deviation based on a preset oxygen set value function table comprises: determining the nonlinear mapping relationship between the main steam flow and the oxygen percentage; performing interpolation correction on the table lookup result according to the oxygen set value function curve, and using a linear interpolation algorithm to calculate the target oxygen set value when the main steam flow is in a preset numerical interval.

3. The method of claim 1, wherein, The method of correcting the air volume instruction by the fuel quantity change rate comprises: determining the nonlinear mapping relationship between the fuel quantity and the air volume, performing gradient correction on the air volume instruction according to a control logic diagram, and calculating a differential compensation amount based on a preset formula when the fuel quantity change rate exceeds a first preset change rate.

4. The method of claim 1, wherein, The method of generating the variable frequency control signal of the forced draught fan based on the adjusted PID parameters and the corrected air volume instruction comprises: setting a minimum air volume protection threshold for the variable frequency control signal, and switching to a minimum air volume protection mode when the corrected air volume instruction is lower than the threshold; applying a rate limit to the variable frequency control signal, and performing rate restriction when the oxygen operator bias change rate exceeds a second preset change threshold.

5. The method of claim 1, wherein, The method further comprises: keeping the current variable frequency control signal unchanged when the forced draught fan switches to the manual mode implementing instruction smooth transition by the bias correction amount when the forced draught fan switches to the automatic mode.

6. A load varying air volume control device characterized by, The method comprises: an obtaining unit, configured to obtain the main steam flow of the boiler and determine the real-time oxygen deviation based on a preset oxygen set value function table, wherein the oxygen set value function table comprises a nonlinear mapping relationship between the main steam flow and the oxygen percentage; an adjusting unit, configured to dynamically adjust the proportional coefficient and the integral coefficient of the PID regulator of the oxygen control loop according to the real-time oxygen deviation and the load instruction change rate; a calculating unit, configured to correct the air volume instruction by the fuel quantity change rate, wherein the air volume instruction is generated by the nonlinear relationship between the fuel quantity and a preset air volume set value function table; a generating unit, configured to generate the variable frequency control signal of the forced draught fan based on the adjusted PID parameters and the corrected air volume instruction.

7. The apparatus of claim 6, wherein, The obtaining unit is further configured to: determine the nonlinear mapping relationship between the main steam flow and the oxygen percentage; perform interpolation correction on the table lookup result according to the oxygen set value function curve, and use a linear interpolation algorithm to calculate the target oxygen set value when the main steam flow is in a preset numerical interval.

8. An electronic device, comprising: The method comprises: at least one processor; and a memory connected with the at least one processor in communication; wherein, The memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the method of any one of claims 1-5.

9. A non-transitory computer-readable storage medium having stored thereon computer instructions, wherein, The computer instructions are for causing the computer to perform the method of any one of claims 1-5.

10. A computer program product, characterised in that, A computer program comprising instructions which, when executed by a processor, implement the method of any one of claims 1-5.

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