Control method and system for heating furnace combustion optimization

Abstract

The application provides a control method and system for heating furnace combustion optimization, comprising the following steps: S1, connecting a control station with an original fuel control system through Ethernet, and connecting a control manual channel of the original fuel control system; S2, performing temperature control, using relevant valve experience data and furnace change response data to confirm the change amount of the valve and the temperature change corresponding relationship; S3, using actual temperature field change data to perform operation judgment, and sending an execution signal to the relevant valve through temperature difference calculation selection; S4, completing air flow control by the relevant air valve; and S5, sending a control signal to the original fuel control system to complete control. The application improves the combustion stability of the heating furnace, reduces the high dependence on manual operation experience at present, reduces gas consumption and oxidation loss, has high control precision, fast speed response, stable combustion trend, reasonable air-fuel ratio, low modification difficulty and connection safety.

Description

Technical Field

[0001] This invention relates to the field of combustion control in metallurgical heating furnaces, specifically to an optimized control method for fuel gas and air in the billet heating process, and more specifically, to a control method and system for optimizing combustion in heating furnaces. Background Technology

[0002] Heating furnaces are generally the biggest energy consumers in hot rolling production lines, accounting for more than half of the total energy consumption. In actual production, due to factors such as gas quality, gas pressure, gas calorific value, air pressure fluctuations, and equipment, manual adjustments are not timely, resulting in large fluctuations in furnace gas temperature, which directly affects product quality.

[0003] Dynamic automatic adjustment of the atmosphere inside the heating furnace is crucial, as the combustion atmosphere significantly impacts oxidation loss and yield. Currently, furnace operators primarily adjust the air-fuel ratio based on factors such as residual oxygen levels and flame color changes, combined with their own experience. This results in a high workload for operators, and the lack of detection methods and inherent lag in controlling the atmosphere across different sections of the furnace makes it difficult to maintain proper control, indicating significant potential for energy savings.

[0004] To improve the combustion stability of heating furnaces, reduce the current high dependence on manual operation experience, and decrease fuel consumption and oxidation loss, this invention provides a combustion optimization control scheme for heating furnaces. This scheme features high control precision, fast response, stable combustion trend, reasonable air-fuel ratio, low modification difficulty, and safe connection.

[0005] Traditional combustion control calculates the required increase or decrease in gas volume based on the deviation between the set temperature and the actual temperature, and then controls the temperature through relevant valves. Due to measurement errors in the gas flow meter and combustion lag within the gas furnace, this method generally results in a slow temperature response, leading to large overshoot and slow reaction in temperature control during heating and cooling.

[0006] Compared to conventional heating furnace combustion control systems, which are generally based on accurate flow detection data and use the theoretical air-fuel ratio as the control basis, supplemented by technologies such as dual cross control and feedforward control, this invention weakens the concept of air-fuel ratio, directly controls valves, and improves the intelligence level of heating furnace combustion control.

[0007] Patent document CN112178685A (application number: CN202010892268.6) discloses a combustion optimization control system for a heating furnace, including: an air regulating valve, an online gas composition detector, a gas flow meter, an online flue gas CO2 detector, and a controller. The controller is used to: acquire the gas flow rate detected by the gas flow meter, the gas composition detected by the online gas composition detector, the CO2 content in the heating furnace detected by the online flue gas CO2 detector, and the current time of data acquisition; obtain a first air flow rate based on the gas flow rate and the gas composition; adjust the flow rate of the air regulating valve to the first air flow rate after a delay based on the current time; further, perform feedback adjustment on the air regulating valve based on the first air flow rate and the CO2 content to obtain a second air flow rate; the adjustment accuracy is further improved through feedback adjustment. However, this invention emphasizes the concept of air-fuel ratio and cannot directly control the valve, resulting in insufficient intelligence in the heating furnace combustion control.

[0008] Patent document CN106468446B (application number: CN201610793434.0) discloses a method for controlling and optimizing combustion in a heating furnace. This method employs a control strategy combining advanced and conventional control algorithms; it uses O2 and CO switching control; and it uses a self-optimizing algorithm to achieve real-time optimization of flue gas oxygen content based on a simplified national standard formula as the optimization target. However, this invention does not allow for quick system modifications to the heating furnace, and its ability to reasonably optimize existing combustion control is insufficient. Summary of the Invention

[0009] To address the shortcomings of existing technologies, the purpose of this invention is to provide a control method and system for optimizing combustion in heating furnaces.

[0010] A control method for optimizing combustion in a heating furnace, provided by the present invention, includes:

[0011] Step S1: Connect the control station to the original fuel control system via Ethernet, and connect to the manual control channel of the original fuel control system;

[0012] Step S2: Perform temperature control, and use relevant valve experience data and furnace change response data to confirm the correspondence between valve changes and temperature changes;

[0013] Step S3: Use actual temperature field change data to perform calculations and judgments, and select the appropriate valve to send the execution signal based on the temperature difference;

[0014] Step S4: Air flow control is completed by the relevant air valves;

[0015] Step S5: Send the control signal to the original fuel control system to complete the control.

[0016] Preferably, in step S1:

[0017] The system uses the OPC communication protocol via Ethernet to connect with the original fuel control system, linking the original fuel control system's manual control channels for gas and air. A soft switching method is added to switch between the original system and this system; all signals use the original system's relevant signals.

[0018] Preferably, in step S2:

[0019] Estimate the output deviation of the gas valve using relevant valve experience data and furnace change response data, calculate the cycle, confirm the correspondence between valve changes and temperature changes, and then change the relevant parameters according to the actual commissioning situation during the subsequent commissioning process.

[0020] Relevant valve experience data includes: the actual response time of each actuator; when there is a feedback signal, the actual time difference between the changes in the output signal and the feedback signal is used; when there is no feedback signal, the change time of relevant flow signals on site is considered.

[0021] The furnace change response data is: segment temperature response time, which is the time from the action of the relevant valve to the reaction time of the heating temperature of that segment, and is the cycle of the gas valve output. The cycle is greater than twice the relevant valve experience data.

[0022] Preferably, in step S3:

[0023] The valve opening is calculated based on actual temperature field change data and temperature difference, and the execution signal is sent to the relevant valve.

[0024] The actual temperature field change data represents the change in heating temperature during the actual operating cycle.

[0025] The temperature difference is the actual difference between the actual heating temperature and the set heating temperature.

[0026] Q_Air=Ratio_AirGas*Q_Gas*Coefficient_Air*Coefficient_K;

[0027] Q_Air represents the air volume;

[0028] Ratio_AirGas is the base air-fuel ratio, extracted from field operation data, and if a calorific value is available, the calorific value change is taken into account.

[0029] Q_Gas represents the gas quantity and requires filtered data processing.

[0030] Coefficient_Air is the human intervention coefficient. When a situation arises that the system cannot recognize but a human can, human intervention is performed.

[0031] Coefficient_K is the system intervention coefficient. When a preset working condition occurs, the system selects an appropriate coefficient from the experience database to achieve rapid adjustment.

[0032] The experience database is derived from data extracted from the actual on-site operation database, data on the direction of temperature field changes in the furnace, and verification data from residual oxygen detection. Different system intervention coefficients are obtained by arranging and combining different situations.

[0033] Preferably, in step S4:

[0034] Air flow is controlled by the relevant air valves. Before the flow control is completed, after the corresponding gas valve automatically actuates, a feedforward parameter is added to the actuation amount of the corresponding air valve to ensure combustion quality.

[0035] Preferably, in step S5:

[0036] The control signal is sent to the original fuel control system via OPC to complete the control.

[0037] A control system for optimizing combustion in a heating furnace, according to the present invention, includes:

[0038] Module M1: Connects the control station to the original fuel control system via Ethernet, and connects to the manual control channel of the original fuel control system;

[0039] Module M2: Performs temperature control, using relevant valve experience data and furnace change response data to confirm the correspondence between valve changes and temperature changes;

[0040] Module M3: Uses actual temperature field change data for calculation and judgment, selects the appropriate valve based on temperature difference, and sends the execution signal to the relevant valve.

[0041] Module M4: Airflow control is achieved through relevant air valves;

[0042] Module M5: Sends control signals to the original fuel control system to complete the control.

[0043] Preferably, in module M1:

[0044] The system uses the OPC communication protocol via Ethernet to connect with the original fuel control system, linking the original fuel control system's manual control channels for gas and air. A soft switching method is added to switch between the original system and this system; all signals use the original system's relevant signals.

[0045] Preferably, in module M2:

[0046] Estimate the output deviation of the gas valve using relevant valve experience data and furnace change response data, calculate the cycle, confirm the correspondence between valve changes and temperature changes, and then change the relevant parameters according to the actual commissioning situation during the subsequent commissioning process.

[0047] Relevant valve experience data includes: the actual response time of each actuator; when there is a feedback signal, the actual time difference between the changes in the output signal and the feedback signal is used; when there is no feedback signal, the change time of relevant flow signals on site is considered.

[0048] The furnace change response data is: segment temperature response time, which is the time from the action of the relevant valve to the reaction time of the heating temperature of that segment, and is the cycle of the gas valve output. The cycle is greater than twice the relevant valve experience data.

[0049] Preferably, in module M3:

[0050] The valve opening is calculated based on actual temperature field change data and temperature difference, and the execution signal is sent to the relevant valve.

[0051] The actual temperature field change data represents the change in heating temperature during the actual operating cycle.

[0052] The temperature difference is the actual difference between the actual heating temperature and the set heating temperature.

[0053] Q_Air=Ratio_AirGas*Q_Gas*Coefficient_Air*Coefficient_K;

[0054] Q_Air represents the air volume;

[0055] Ratio_AirGas is the base air-fuel ratio, extracted from field operation data, and if a calorific value is available, the calorific value change is taken into account.

[0056] Q_Gas represents the gas quantity and requires filtered data processing.

[0057] Coefficient_Air is the human intervention coefficient. When a situation arises that the system cannot recognize but a human can, human intervention is performed.

[0058] Coefficient_K is the system intervention coefficient. When a preset working condition occurs, the system selects an appropriate coefficient from the experience database to achieve rapid adjustment.

[0059] The experience database is derived from data extracted from the actual on-site operation database, data on the direction of temperature field changes in the furnace, and verification data from residual oxygen detection. Different system intervention coefficients are obtained by arranging and combining different situations.

[0060] Preferably, in module M4:

[0061] Air flow is controlled by the relevant air valves. Before the flow control is completed, after the corresponding gas valve automatically actuates, a feedforward parameter is added to the actuation amount of the corresponding air valve to ensure combustion quality.

[0062] Preferably, in module M5:

[0063] The control signal is sent to the original fuel control system via OPC to complete the control.

[0064] Compared with the prior art, the present invention has the following beneficial effects:

[0065] 1. This invention improves the combustion stability of the heating furnace, reduces the current high dependence on manual operation experience, and reduces gas consumption and oxidation loss;

[0066] 2. This invention features high control precision, fast speed response, stable combustion trend, reasonable air-fuel ratio, low modification difficulty, and safe connection;

[0067] 3. This invention allows for quick system modifications to the heating furnace, reasonable optimization of existing combustion control, and more rational control of gas and air, which can effectively stabilize temperature control, reduce gas consumption and oxidation loss;

[0068] 4. This invention can effectively avoid interference from gas flow, achieve rapid and stable heating and cooling, minimize overshoot, and reduce the amount of valve actuation during heat preservation, resulting in stable and efficient operation.

[0069] 5. The intermediate parameters and control parameters of the system are clearly visible, eliminating the need to download programs and facilitating operation and debugging. Attached Figure Description

[0070] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0071] Figure 1 System architecture diagram;

[0072] Figure 2 This is a diagram of the system's internal computing modules. Detailed Implementation

[0073] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0074] Example 1:

[0075] According to the present invention, a control method for optimizing combustion in a heating furnace is provided, such as... Figure 1-2 ,include:

[0076] Step S1: Connect the control station to the original fuel control system via Ethernet, and connect to the manual control channel of the original fuel control system;

[0077] Step S2: Perform temperature control, and use relevant valve experience data and furnace change response data to confirm the correspondence between valve changes and temperature changes;

[0078] Step S3: Use actual temperature field change data to perform calculations and judgments, and select the appropriate valve to send the execution signal based on the temperature difference;

[0079] Step S4: Air flow control is completed by the relevant air valves;

[0080] Step S5: Send the control signal to the original fuel control system to complete the control.

[0081] Specifically, in step S1:

[0082] The system uses the OPC communication protocol via Ethernet to connect with the original fuel control system, linking the original fuel control system's manual control channels for gas and air. A soft switching method is added to switch between the original system and this system; all signals use the original system's relevant signals.

[0083] Specifically, in step S2:

[0084] Estimate the output deviation of the gas valve using relevant valve experience data and furnace change response data, calculate the cycle, confirm the correspondence between valve changes and temperature changes, and then change the relevant parameters according to the actual commissioning situation during the subsequent commissioning process.

[0085] Relevant valve experience data includes: the actual response time of each actuator; when there is a feedback signal, the actual time difference between the changes in the output signal and the feedback signal is used; when there is no feedback signal, the change time of relevant flow signals on site is considered.

[0086] The furnace change response data is: segment temperature response time, which is the time from the action of the relevant valve to the reaction time of the heating temperature of that segment, and is the cycle of the gas valve output. The cycle is greater than twice the relevant valve experience data.

[0087] Specifically, in step S3:

[0088] The valve opening is calculated based on actual temperature field change data and temperature difference, and the execution signal is sent to the relevant valve.

[0089] The actual temperature field change data represents the change in heating temperature during the actual operating cycle.

[0090] The temperature difference is the actual difference between the actual heating temperature and the set heating temperature.

[0091] Q_Air=Ratio_AirGas*Q_Gas*Coefficient_Air*Coefficient_K;

[0092] Q_Air represents the air volume;

[0093] Ratio_AirGas is the base air-fuel ratio, extracted from field operation data, and if a calorific value is available, the calorific value change is taken into account.

[0094] Q_Gas represents the gas quantity and requires filtered data processing.

[0095] Coefficient_Air is the human intervention coefficient. When a situation arises that the system cannot recognize but a human can, human intervention is performed.

[0096] Coefficient_K is the system intervention coefficient. When a preset working condition occurs, the system selects an appropriate coefficient from the experience database to achieve rapid adjustment.

[0097] The experience database is derived from data extracted from the actual on-site operation database, data on the direction of temperature field changes in the furnace, and verification data from residual oxygen detection. Different system intervention coefficients are obtained by arranging and combining different situations.

[0098] Specifically, in step S4:

[0099] Air flow is controlled by the relevant air valves. Before the flow control is completed, after the corresponding gas valve automatically actuates, a feedforward parameter is added to the actuation amount of the corresponding air valve to ensure combustion quality.

[0100] Specifically, in step S5:

[0101] The control signal is sent to the original fuel control system via OPC to complete the control.

[0102] Example 2:

[0103] Example 2 is a preferred embodiment of Example 1, and is used to illustrate the present invention in more detail.

[0104] Those skilled in the art can understand the control method for optimizing combustion in a heating furnace provided by the present invention as a specific implementation of a control system for optimizing combustion in a heating furnace, that is, the control system for optimizing combustion in a heating furnace can be implemented by executing the steps of the control method for optimizing combustion in a heating furnace.

[0105] A control system for optimizing combustion in a heating furnace, according to the present invention, includes:

[0106] Module M1: Connects the control station to the original fuel control system via Ethernet, and connects to the manual control channel of the original fuel control system;

[0107] Module M2: Performs temperature control, using relevant valve experience data and furnace change response data to confirm the correspondence between valve changes and temperature changes;

[0108] Module M3: Uses actual temperature field change data for calculation and judgment, selects the appropriate valve based on temperature difference, and sends the execution signal to the relevant valve.

[0109] Module M4: Airflow control is achieved through relevant air valves;

[0110] Module M5: Sends control signals to the original fuel control system to complete the control.

[0111] Specifically, in module M1:

[0112] The system uses the OPC communication protocol via Ethernet to connect with the original fuel control system, linking the original fuel control system's manual control channels for gas and air. A soft switching method is added to switch between the original system and this system; all signals use the original system's relevant signals.

[0113] Specifically, in module M2:

[0114] Estimate the output deviation of the gas valve using relevant valve experience data and furnace change response data, calculate the cycle, confirm the correspondence between valve changes and temperature changes, and then change the relevant parameters according to the actual commissioning situation during the subsequent commissioning process.

[0115] Relevant valve experience data includes: the actual response time of each actuator; when there is a feedback signal, the actual time difference between the changes in the output signal and the feedback signal is used; when there is no feedback signal, the change time of relevant flow signals on site is considered.

[0116] The furnace change response data is: segment temperature response time, which is the time from the action of the relevant valve to the reaction time of the heating temperature of that segment, and is the cycle of the gas valve output. The cycle is greater than twice the relevant valve experience data.

[0117] Specifically, in module M3:

[0118] The valve opening is calculated based on actual temperature field change data and temperature difference, and the execution signal is sent to the relevant valve.

[0119] The actual temperature field change data represents the change in heating temperature during the actual operating cycle.

[0120] The temperature difference is the actual difference between the actual heating temperature and the set heating temperature.

[0121] Q_Air=Ratio_AirGas*Q_Gas*Coefficient_Air*Coefficient_K;

[0122] Q_Air represents the air volume;

[0123] Ratio_AirGas is the base air-fuel ratio, extracted from field operation data, and if a calorific value is available, the calorific value change is taken into account.

[0124] Q_Gas represents the gas quantity and requires filtered data processing.

[0125] Coefficient_Air is the human intervention coefficient. When a situation arises that the system cannot recognize but a human can, human intervention is performed.

[0126] Coefficient_K is the system intervention coefficient. When a preset working condition occurs, the system selects an appropriate coefficient from the experience database to achieve rapid adjustment.

[0127] The experience database is derived from data extracted from the actual on-site operation database, data on the direction of temperature field changes in the furnace, and verification data from residual oxygen detection. Different system intervention coefficients are obtained by arranging and combining different situations.

[0128] Specifically, in module M4:

[0129] Air flow is controlled by the relevant air valves. Before the flow control is completed, after the corresponding gas valve automatically actuates, a feedforward parameter is added to the actuation amount of the corresponding air valve to ensure combustion quality.

[0130] Specifically, in module M5:

[0131] The control signal is sent to the original fuel control system via OPC to complete the control.

[0132] Example 3:

[0133] Example 3 is a preferred example of Example 1, and is used to illustrate the present invention in more detail.

[0134] Add a control station and connect it to the original heating furnace gas control PLC via Ethernet using the OPC communication protocol. To reduce the amount of modification to the L1 control program and lower the risk, the new system can be launched without shutting down the original system. Connect the relevant manual control channels for gas and air of the original gas control system and add a soft switching method to switch between the original system and this system.

[0135] This control method ignores interference from gas flow during temperature control. It uses relevant valve experience data T_Response_Fv and furnace change response data T_Response_Furnace to estimate the gas valve output deviation Cx and calculate the period T_T, thus confirming the correspondence between valve changes and temperature changes. Further optimization of relevant parameters is performed during commissioning based on actual conditions. Valve opening is calculated based on actual temperature field change data Delta_T, temperature difference Delta_SP, and other relevant parameters, and the execution signal is directly sent to the relevant valves. This effectively avoids interference from gas flow, resulting in rapid and stable temperature rise and fall with minimal overshoot. It also minimizes valve movement during heat preservation, ensuring stability and high efficiency.

[0136] T_Response_Fv - The actual response time of each actuator. If there is a feedback signal, the actual time difference between the changes in the output signal and the feedback signal can be used; if there is no feedback signal, the change time of the relevant flow signal on site must be considered.

[0137] T_Response_Furnace - Segment temperature response time, that is, the time from the action of the relevant valve to the reaction time of the heating temperature segment. This parameter is the period T_T output by gas valve C, and this period should be greater than T_Response_Fv×2;

[0138] Delta_T represents the change in heating temperature during the actual operating cycle;

[0139] Dlelta_SP represents the actual difference between the actual heating temperature and the set heating temperature.

[0140]

[0141] Air quantity Q_Air = Ratio_AirGas * Q_Gas * Coefficient_Air * Coefficient_K;

[0142] Ratio_AirGas - the basic air-fuel ratio, which is generally extracted from on-site operating data. If a calorific value meter is available, the calorific value changes can be referenced.

[0143] Q_Gas - Gas quantity, generally requires filtered data processing;

[0144] Coefficient_Air - Human intervention coefficient. When special situations arise that the system cannot identify but can be identified manually, human intervention can be carried out.

[0145] Coefficient_K - System intervention coefficient. When certain special operating conditions occur, such as sudden changes in calorific value or rapid cooling, and the air volume needs to be changed rapidly, the system selects an appropriate coefficient through the experience database to achieve rapid adjustment.

[0146] The experience database extracts data such as changes in gas volume (changes in gas valves), direction of calorific value change (changes), and direction of temperature field change in the furnace (changes) from the actual on-site operation database, as well as verification data from residual oxygen detection. Different combinations of these data yield different Coefficient_K - system intervention coefficients.

[0147] Then, the relevant air valves quickly complete the air flow control. Before the flow control is completed, a feedforward parameter can be quickly added to the corresponding air valve action amount after the corresponding gas valve automatically acts to ensure rapid and reasonable combustion.

[0148] The system's intermediate parameters and control parameters are clearly visible, eliminating the need to download any programs and facilitating operation and debugging.

[0149] Example 4:

[0150] Example 4 is a preferred example of Example 1, which is used to illustrate the present invention in more detail.

[0151] By adding a control station to the existing Ethernet network, this station will be integrated into the existing heating furnace control system. The system will be installed on the control station and connected to the existing control system via the OPC protocol. It will take over the manual channels for combustion control and valve control from the existing PLC system. All signals will use the relevant PLC signals from the original system. The system will perform optimization calculations and then send the more appropriate control signals back to the existing PLC via OPC to complete the control.

[0152] like Figure 2 The internal calculation steps of the system are as follows:

[0153] 1. The main data collected includes: temperature setting, actual temperature, medium pressure, medium flow rate, valve opening, etc.

[0154] 2. The main functions of data preprocessing are: to remove obviously unreasonable data (such as exceeding limits) and to perform smoothing and filtering on relevant data;

[0155] 3. Combustion condition tracking and analysis:

[0156] (1) Determine which stage the current temperature is in: rapid heating, slow heating, holding, slow cooling, or rapid cooling, based on the deviation between the set value and the actual value.

[0157] (2) Calculate and issue the valve opening degree in real time based on the working conditions;

[0158] 4. Based on the actual valve opening changes and the actual temperature changes and rates, determine the optimal correspondence between the air and gas valves.

[0159] 5. The knowledge base mainly combines past project experience and the operational experience of on-site personnel, forming logical rules for program calls. For example, based on operational experience, a certain valve is prone to jamming in a certain range, and the jamming range should be avoided as much as possible during actual control.

[0160] 6. A heartbeat signal and some alarm information should be added to the heating furnace PLC controller. In special circumstances, such as when the communication between the system and the PLC is interrupted, an alarm should be triggered in time and the system should switch to manual mode or perform other operations.

[0161] Those skilled in the art will understand that, in addition to implementing the system, apparatus, and their modules provided by this invention in purely computer-readable program code, the same program can be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system, apparatus, and their modules provided by this invention can be considered a hardware component, and the modules included therein for implementing various programs can also be considered structures within the hardware component; alternatively, modules for implementing various functions can be considered both software programs implementing the method and structures within the hardware component.

[0162] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A control method for optimizing combustion in a heating furnace, characterized in that, include: Step S1: Connect the control station to the original fuel control system via Ethernet, and connect to the manual control channel of the original fuel control system; Step S2: Perform temperature control, and use relevant valve experience data and furnace change response data to confirm the correspondence between valve changes and temperature changes; Step S3: Use actual temperature field change data for calculation and judgment, and select the appropriate valve based on the temperature difference to send the execution signal to the relevant valve; the temperature difference is the actual difference between the actual heating temperature and the set heating temperature; Step S4: Air flow control is completed by the relevant air valves; Step S5: Send the control signal to the original fuel control system to complete the control; In step S2: Estimate the output deviation of the gas valve using relevant valve experience data and furnace change response data, calculate the cycle, confirm the correspondence between valve changes and temperature changes, and then change the relevant parameters according to the actual commissioning situation during the subsequent commissioning process. Relevant valve experience data includes: the actual response time of each actuator; When there is a feedback signal, use the actual time difference between the changes in the output signal and the feedback signal; when there is no feedback signal, consider the change time of relevant flow signals on site. The furnace change response data is: segment temperature response time, which is the time from the action of the relevant valve to the reaction time of the segment heating temperature, and is the cycle of the gas valve output. The cycle is greater than twice the relevant valve experience data.

2. The control method for optimizing combustion in a heating furnace according to claim 1, characterized in that, In step S1: The system uses the OPC communication protocol via Ethernet to connect with the original fuel control system, linking the original fuel control system's manual control channels for gas and air. A soft switching method is added to switch between the original system and this system; all signals use the original system's relevant signals.

3. The control method for optimizing combustion in a heating furnace according to claim 1, characterized in that, In step S3: The valve opening is calculated based on actual temperature field change data and temperature difference, and the execution signal is sent to the relevant valve. The actual temperature field change data represents the change in heating temperature during the actual operating cycle. Q_Air=Ratio_AirGas*Q_Gas*Coefficient_Air*Coefficient_K; Q_Air represents the air volume; Ratio_AirGas is the base air-fuel ratio, extracted from field operation data, and if a calorific value is available, the calorific value change is taken into account. Q_Gas represents the gas quantity and requires filtered data processing. Coefficient_Air is the human intervention coefficient. When a situation arises that the system cannot recognize but a human can, human intervention is performed. Coefficient_K is the system intervention coefficient. When a preset working condition occurs, the system selects an appropriate coefficient from the experience database to achieve rapid adjustment. The experience database is derived from data extracted from the actual on-site operation database, data on the direction of temperature field changes in the furnace, and verification data from residual oxygen detection. Different system intervention coefficients are obtained by arranging and combining different situations.

4. The control method for optimizing combustion in a heating furnace according to claim 1, characterized in that: In step S4: Air flow is controlled by the relevant air valves. Before the flow control is completed, after the corresponding gas valve automatically actuates, a feedforward parameter is added to the actuation amount of the corresponding air valve to ensure combustion quality. In step S5: The control signal is sent to the original fuel control system via OPC to complete the control.

5. A control system for optimizing combustion in a heating furnace, characterized in that, include: Module M1: Connects the control station to the original fuel control system via Ethernet, and connects to the manual control channel of the original fuel control system; Module M2: Performs temperature control, using relevant valve experience data and furnace change response data to confirm the correspondence between valve changes and temperature changes; Module M3: Uses actual temperature field change data for calculation and judgment, calculates and selects the appropriate valve based on the temperature difference, and sends the execution signal to the relevant valve. The temperature difference is the actual difference between the actual heating temperature and the set heating temperature. Module M4: Airflow control is achieved through relevant air valves; Module M5: Sends control signals to the original fuel control system to complete the control; In module M2: Estimate the output deviation of the gas valve using relevant valve experience data and furnace change response data, calculate the cycle, confirm the correspondence between valve changes and temperature changes, and then change the relevant parameters according to the actual commissioning situation during the subsequent commissioning process. Relevant valve experience data includes: the actual response time of each actuator; When there is a feedback signal, use the actual time difference between the changes in the output signal and the feedback signal; when there is no feedback signal, consider the change time of relevant flow signals on site. The furnace change response data is: segment temperature response time, which is the time from the action of the relevant valve to the reaction time of the segment heating temperature, and is the cycle of the gas valve output. The cycle is greater than twice the relevant valve experience data.

6. The control system for optimizing combustion in a heating furnace according to claim 5, characterized in that, In module M1: The system uses the OPC communication protocol via Ethernet to connect with the original fuel control system, linking the original fuel control system's manual control channels for gas and air. A soft switching method is added to switch between the original system and this system; all signals use the original system's relevant signals.

7. The control system for optimizing combustion in a heating furnace according to claim 5, characterized in that, In module M3: The valve opening is calculated based on actual temperature field change data and temperature difference, and the execution signal is sent to the relevant valve. The actual temperature field change data represents the change in heating temperature during the actual operating cycle. Q_Air=Ratio_AirGas*Q_Gas*Coefficient_Air*Coefficient_K; Q_Air represents the air volume; Ratio_AirGas is the base air-fuel ratio, extracted from field operation data, and if a calorific value is available, the calorific value change is taken into account. Q_Gas represents the gas quantity and requires filtered data processing. Coefficient_Air is the human intervention coefficient. When a situation arises that the system cannot recognize but a human can, human intervention is performed. Coefficient_K is the system intervention coefficient. When a preset working condition occurs, the system selects an appropriate coefficient from the experience database to achieve rapid adjustment. The experience database is derived from data extracted from the actual on-site operation database, data on the direction of temperature field changes in the furnace, and verification data from residual oxygen detection. Different system intervention coefficients are obtained by arranging and combining different situations.

8. The control system for combustion optimization in a heating furnace according to claim 5, characterized in that: In module M4: Air flow is controlled by the relevant air valves. Before the flow control is completed, after the corresponding gas valve automatically actuates, a feedforward parameter is added to the actuation amount of the corresponding air valve to ensure combustion quality. In module M5: The control signal is sent to the original fuel control system via OPC to complete the control.

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