Full-premixing stable combustion control method, device, equipment and medium

Abstract

The invention discloses a full-premixing stable combustion control method, device and equipment and a medium, and relates to the technical field of combustion control, and the method comprises flue resistance self-learning and soft fire stable flame control. In the flue learning mode, the rotating speed of a fan is gradually increased from a preset minimum value to a maximum value by adjusting the output PWM duty ratio of the fan, the actual PWM duty ratio of each rotating speed point is obtained and compared with a pre-stored standard curve, accordingly, the output PWM duty ratio is adjusted to enable the actual value to be equal to the standard value, and a calibration parameter curve of the current working condition is recorded and formed; and subsequently controlling the fan according to the calibration parameter curve. The soft fire flame stabilization control monitors the flame feedback current at the minimum rotating speed, and if the flame feedback current is smaller than a calibration threshold value, the minimum running rotating speed is increased until the current reaches the standard so as to guarantee the stability of the soft fire. By means of parameter self-adaptive calibration, the problem of unstable combustion caused by installation condition differences, low actual working condition air pressure, fuel gas component changes and the like is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of combustion control technology, and in particular to a fully premixed stable combustion control method, apparatus, equipment and medium. Background Technology

[0002] Fully premixed wall-hung boilers are commonly used heating equipment. They mix gas and air in a specific ratio before combustion, offering advantages such as high efficiency and cleanliness. However, these systems are highly dependent on environmental conditions and gas composition during actual use. Current conventional fully premixed wall-hung boilers are mostly controlled by manually adjustable valves, meaning a fixed air-fuel ratio is set at the factory according to standard operating conditions. However, after installation and operation, differences in gas composition across regions, fluctuations in gas composition even within the same region over time, and frequent changes in pipeline pressure during peak and off-peak gas consumption periods all contribute to discrepancies between the actual supplied gas characteristics and the factory-set conditions. In such cases, the fixed air-fuel ratio setting struggles to maintain optimal combustion, easily leading to unstable combustion phenomena, such as flickering and fluctuating flames, or even abnormal resonance or unexpected flameout, severely impacting user experience and equipment reliability.

[0003] Furthermore, variations in equipment installation conditions present additional challenges. The length, number of bends, and installation routes of exhaust ducts in residential buildings differ, resulting in significant variations in exhaust system resistance. Excessive exhaust resistance can affect the fan's proper injection of gas, leading to a reduction in the actual amount of gas participating in combustion, a decrease in combustion load, and a deviation of the air-fuel ratio from the optimal range. This not only causes incomplete combustion and increased carbon buildup but may also trigger safety hazards such as backfire or flameout. Existing manual valve adjustment methods cannot adaptively adjust to these installation differences, making it difficult for the equipment to maintain stable and efficient combustion under certain actual operating conditions. Summary of the Invention

[0004] This invention provides a fully premixed stable combustion control method, apparatus, equipment, and medium, aiming to solve the technical problem of: how to provide a control solution that can automatically adjust operating parameters according to installation conditions to achieve stable and reliable operation of the fully premixed combustion system under various actual environments.

[0005] In a first aspect, embodiments of the present invention provide a fully premixed stable combustion control method, comprising: In response to a trigger signal, the fan is controlled to enter the flue learning mode. In the flue learning mode, the fan speed is controlled to gradually increase from the preset minimum speed to the preset maximum speed by adjusting the output PWM duty cycle of the fan. For multiple different speed points, obtain the actual PWM duty cycle of the fan at the current speed point; The actual PWM duty cycle is compared with the standard PWM duty cycle at the same speed point in the pre-stored standard PWM duty cycle curve; Based on the comparison results, the output PWM duty cycle of the fan at the current speed point is adjusted so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle. Record the output PWM duty cycle corresponding to each speed point after adjustment to form the calibration parameter curve under the current operating condition, and update the standard PWM duty cycle curve to the calibration parameter curve so as to control the speed of the fan according to the calibration parameter curve during subsequent combustion operation.

[0006] Optionally, adjusting the output PWM duty cycle of the fan at the current speed point based on the comparison result, so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle, includes: If the actual PWM duty cycle is less than the standard PWM duty cycle, then increase the output PWM duty cycle of the fan at the current speed point so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle; If the actual PWM duty cycle is greater than the standard PWM duty cycle, then the output PWM duty cycle of the fan at the current speed point is reduced so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle.

[0007] Optionally, the method further includes: when the cumulative running time of the combustion system reaches a preset learning cycle, returning to the step of obtaining the actual PWM duty cycle of the fan at the current speed point for multiple different speed points, so as to update the calibration parameter curve.

[0008] Optionally, the method further includes: Determine whether the PWM duty cycle determined based on the updated calibration parameter curve at the maximum speed point exceeds a preset safety threshold. If the PWM duty cycle determined based on the updated calibration parameter curve exceeds the safety threshold, the combustion system is controlled to enter a shutdown protection state.

[0009] Optionally, the method further includes: During combustion operation, the flame feedback current is continuously monitored; When the fan runs to the minimum operating speed determined according to the calibration parameter curve, it is determined whether the current flame feedback current is less than the preset calibration current threshold. If the flame feedback current is less than the calibrated current threshold, the minimum operating speed of the fan is increased, and the flame feedback current after the speed is increased is monitored until the flame feedback current is greater than or equal to the calibrated current threshold.

[0010] Optionally, increasing the minimum operating speed of the fan and continuing to monitor the flame feedback current after increasing the speed until the flame feedback current is greater than or equal to the calibrated current threshold specifically includes: Increase the minimum operating speed of the fan by a preset step value to obtain the adjusted speed; Obtain the flame feedback current at the adjusted rotation speed; If the flame feedback current at the adjusted speed is greater than or equal to the calibrated current threshold, and the adjusted speed is less than or equal to the preset speed limit, then the adjusted speed is set as the new minimum operating speed. If the flame feedback current at the adjusted speed is less than the calibrated current threshold, and the adjusted speed is less than the preset upper speed limit, then proceed to the step of increasing the minimum operating speed of the fan by a preset step value to obtain the adjusted speed.

[0011] Optionally, the method further includes: If the adjusted rotational speed is greater than or equal to the preset upper limit of rotational speed, the combustion system is controlled to enter a fault shutdown state.

[0012] Secondly, embodiments of the present invention also provide a fully premixed stable combustion control device, which includes a unit for performing the above-described method.

[0013] Thirdly, embodiments of the present invention also provide a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the above-described method.

[0014] Fourthly, embodiments of the present invention also provide a computer-readable storage medium storing a computer program that, when executed by a processor, can implement the above-described method.

[0015] This invention provides a fully premixed stable combustion control method, apparatus, device, and medium. The method includes: responding to a trigger signal, controlling a fan to enter a flue gas learning mode; in this mode, adjusting the output PWM duty cycle of the fan to gradually increase its speed from a preset minimum to a preset maximum; acquiring the actual PWM duty cycle of the fan at multiple different speed points; comparing the actual PWM duty cycle with the standard PWM duty cycle at the same speed point in a pre-stored standard PWM duty cycle curve; adjusting the output PWM duty cycle of the fan at the current speed point based on the comparison result, so that the adjusted actual PWM duty cycle equals the standard PWM duty cycle; recording the output PWM duty cycle corresponding to each speed point after adjustment to form a calibration parameter curve under the current operating condition; and updating the standard PWM duty cycle curve to the calibration parameter curve, so that the fan speed is controlled according to the calibration parameter curve during subsequent combustion operation. This invention effectively solves the combustion instability problem caused by differences in installation conditions through flue gas resistance self-learning and parameter adaptive calibration. In initialization learning mode, the system uses closed-loop regulation to ensure that the actual driving energy of the fan at each speed point is consistent with the standard operating condition, thereby offsetting the influence of actual flue resistance and generating personalized calibration parameter curves. This method ensures that the combustion system can maintain a precise air-fuel ratio and stable combustion state in various real-world environments, avoiding flameout, resonance, and backfire caused by inaccurate airflow, and achieving adaptive and reliable operation across the entire operating range. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic flowchart of a fully premixed stable combustion control method provided in an embodiment of the present invention; Figure 2 This is a schematic block diagram of a computer device provided in an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0020] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0021] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0022] As used in this specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0023] Please see Figure 1 This invention provides a fully premixed stable combustion control method. By introducing a set of control logic for flue resistance self-learning and parameter self-calibration, it effectively solves the combustion instability problem caused by differences in installation conditions and changes in gas operating conditions. Specifically, the method includes the following steps: S1, in response to the trigger signal, controls the fan to enter the flue learning mode. In the flue learning mode, by adjusting the output PWM duty cycle of the fan, the fan speed is controlled to gradually increase from the preset minimum speed to the preset maximum speed.

[0024] In practice, after the entire unit is installed and powered on for the first time, the installer can generate a trigger signal by pressing and holding a specific button on the operator. The controller responds to this signal and controls the fan to enter the flue gas learning mode. In the flue gas learning mode, the controller sends a control signal to the fan drive circuit through its PWM output port, gradually adjusting the output PWM duty cycle, so that the fan speed starts from the system's preset minimum speed FL and gradually increases in fixed speed increments R revolutions per minute until it reaches the preset maximum speed FH.

[0025] S2, for multiple different speed points, obtain the actual PWM duty cycle of the fan at the current speed point.

[0026] In practice, at each speed point where the speed increases stepwise, the controller obtains the actual PWM duty cycle of the fan at that speed point through the speed feedback circuit.

[0027] In this embodiment of the invention, when the system responds to the trigger signal and enters the flue learning mode, it controls the fan speed to gradually scan from a preset minimum value to a preset maximum value by adjusting the output PWM duty cycle of the fan. This scanning process does not simply read the speed, but actively acquires the actual PWM duty cycle of the fan synchronously at multiple discrete speed points.

[0028] It should be noted that, in this embodiment of the invention, the output PWM duty cycle refers to the duty cycle command value of the pulse width modulation signal sent by the controller to the fan drive circuit, used to set the target drive level of the fan. The actual PWM duty cycle is an equivalent value characterizing the actual operating drive level of the fan under the current load, obtained through a system feedback mechanism (e.g., based on the actual speed measured by the speed sensor and the pre-stored relationship of motor characteristics). By comparing the actual PWM duty cycle at the same speed point with the standard PWM duty cycle, the deviation of the current actual load (such as flue resistance) from the standard load can be quantified.

[0029] The root cause of the difference between the actual PWM duty cycle and the standard PWM duty cycle lies in the fact that the flue resistance encountered by the fan during actual operation (determined by installation length, bends, blockages, etc.) differs from the standard resistance used when establishing the standard PWM duty cycle curve. The core of this method lies in closed-loop comparison and adjustment: the system compares the measured actual PWM duty cycle with the standard PWM duty cycle at the corresponding target speed point in the standard PWM duty cycle curve. This comparison directly quantifies the deviation of the actual resistance from the standard resistance. If the actual resistance is greater, more drive energy is usually required to reach the target speed, and the system will increase the output PWM duty cycle command; conversely, it will decrease. Through iterative adjustment, the fan is eventually made to run stably at the target speed, and the derived actual PWM duty cycle equals the standard PWM duty cycle at that speed. This means that the system, through adaptive adjustment, offsets the influence of the actual resistance, ensuring that the same speed command produces the same effective airflow as under standard operating conditions in any installation environment. Recording the adjusted output PWM duty cycle at all target speed points forms a calibration parameter curve adapted to the current specific operating conditions.

[0030] S3, compare the actual PWM duty cycle with the standard PWM duty cycle at the same speed point in the pre-stored standard PWM duty cycle curve.

[0031] In practice, the controller accesses the standard PWM duty cycle curve calibrated under standard resistance conditions pre-stored in its non-volatile memory and reads the standard PWM duty cycle value corresponding to that speed point. The controller then compares the acquired actual PWM duty cycle with this standard PWM duty cycle value in real time.

[0032] In this embodiment of the invention, the actual PWM duty cycle at each speed point is compared in real time with the corresponding value in the pre-stored standard PWM duty cycle curve. This standard curve represents the reference drive energy required to reach the same speed under ideal conditions with no additional resistance or standard resistance. The comparison step is a crucial first diagnostic step, and its difference directly quantifies the additional resistance effect brought about by the currently installed flue.

[0033] S4. Based on the comparison results, adjust the output PWM duty cycle of the fan at the current speed point so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle.

[0034] In practice, based on the comparison results, the controller dynamically adjusts its output PWM duty cycle command: if the actual PWM duty cycle is less than the standard PWM duty cycle, the output PWM duty cycle is increased; if the actual PWM duty cycle is greater than the standard PWM duty cycle, the output PWM duty cycle is decreased. Through closed-loop regulation, the actual operating PWM duty cycle of the fan is made equal to the standard PWM duty cycle. This process is repeated at each speed point.

[0035] In this embodiment of the invention, the output PWM duty cycle of the fan at the current speed point is dynamically increased or decreased depending on whether the actual PWM duty cycle is less than or greater than the standard PWM duty cycle. The goal of the adjustment is not arbitrary, but specifically to make the adjusted actual PWM duty cycle equal to the corresponding standard PWM duty cycle. The physical meaning of this closed-loop adjustment process is that, through feedback control, the system forces the fan, under the current actual resistance environment, to have its input drive energy (represented by the PWM duty cycle) calibrated to be consistent with the standard drive energy required to generate the same airflow under ideal conditions. In other words, it offsets the additional resistance introduced by the length of the flue, the number of bends, or slight blockages, ensuring that the effective airflow actually provided by the fan can be restored to the standard airflow level expected in the design at any given speed command.

[0036] In some preferred embodiments, adjusting the output PWM duty cycle of the fan at the current speed point based on the comparison result, so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle, includes: if the actual PWM duty cycle is less than the standard PWM duty cycle, increasing the output PWM duty cycle of the fan at the current speed point, so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle; if the actual PWM duty cycle is greater than the standard PWM duty cycle, decreasing the output PWM duty cycle of the fan at the current speed point, so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle.

[0037] In practice, the controller performs precise numerical adjustments after comparing the actual PWM duty cycle with the standard PWM duty cycle. When the actual PWM duty cycle is detected to be less than the standard PWM duty cycle, the controller gradually increases the PWM duty cycle value output to the fan drive circuit in a preset step size, and continuously monitors the actual PWM duty cycle. This incrementing process continues until the deviation between the actual PWM duty cycle and the standard PWM duty cycle is within a preset error range, at which point the actual PWM duty cycle is determined to be equal to the standard PWM duty cycle.

[0038] Furthermore, if the actual PWM duty cycle is detected to be greater than the standard PWM duty cycle, the controller gradually decreases its output PWM duty cycle value by a preset step size, and continuously monitors the actual PWM duty cycle. This decreasing process will continue until the deviation between the actual PWM duty cycle and the standard PWM duty cycle is within a preset error range, at which point the actual PWM duty cycle is determined to be equal to the standard PWM duty cycle.

[0039] This adjustment is performed independently at each target speed point, ensuring that the drive energy (characterized by PWM duty cycle) of the fan is precisely calibrated at each specific speed command to counteract the effect of the current flue resistance on the airflow.

[0040] This embodiment provides a precise and reliable closed-loop control mechanism. By explicitly setting the control target to make the actual PWM duty cycle equal to the standard PWM duty cycle, the system achieves standardized calibration of the fan output characteristics. Regardless of the actual flue resistance, the system can use feedback control to force the fan's input power (PWM duty cycle) at the current speed to be adjusted to the level required to generate the standard air volume.

[0041] S5. Record the output PWM duty cycle corresponding to each speed point after adjustment to form the calibration parameter curve under the current operating condition, and update the standard PWM duty cycle curve to the calibration parameter curve so as to control the speed of the fan according to the calibration parameter curve in the subsequent combustion operation.

[0042] In practice, after the entire learning process from minimum to maximum speed is completed, the controller records the adjusted output PWM duty cycle set for each speed point. Based on this set of output PWM duty cycles, it fits a calibration parameter curve for the current specific installation environment (flue length, elbow resistance, etc.). Subsequently, the controller uses this newly generated calibration parameter curve to cover or replace the original standard PWM duty cycle curve and stores the updated data. During subsequent normal combustion operation, the system will use this calibration parameter curve to obtain the output PWM duty cycle corresponding to each target speed to control the fan speed.

[0043] In some preferred embodiments, the method further includes: when the cumulative running time of the combustion system reaches a preset learning cycle, returning to the step of obtaining the actual PWM duty cycle of the fan at the current speed point for multiple different speed points, so as to update the calibration parameter curve.

[0044] In practice, after the combustion system enters the daily use phase, the timer inside the controller continuously accumulates the running time. When the accumulated running time reaches a preset learning cycle (e.g., 30 days), the controller automatically triggers an update learning process without requiring user intervention. The system automatically returns to the step of obtaining the actual PWM duty cycle of the fan at the current speed point for multiple different speed points to update the calibration parameter curve. Specifically, the fan speed is gradually increased from the minimum speed FL to the maximum speed FH, and during this process, the actual PWM duty cycle of the fan in the current operating state is obtained again for multiple speed points. At this time, the system compares and adjusts these newly obtained actual PWM duty cycle data with the PWM duty cycle values ​​at the corresponding speed points in the currently used calibration parameter curve (i.e., the curve stored after the last learning). The goal of the adjustment is to make the newly obtained actual PWM duty cycle equal to the value in the current calibration parameter curve. After this new round of closed-loop adjustment, a set of updated output PWM duty cycle data is formed, and this new data is used to overwrite the original calibration parameter curve, thereby completing the update of the calibration parameter curve.

[0045] This embodiment introduces a time-triggered periodic self-learning function, enabling the system to possess long-term adaptability and self-maintenance capabilities. It can cope with changes in the flue system's state that may occur during use, such as the gradual accumulation of dust and foreign objects on the inner wall of the flue causing a slow increase in resistance, or slight changes caused by external environmental factors. By periodically re-executing the learning process, the system can promptly detect deviations between the current control parameters (calibration parameter curve) and the latest actual resistance, and proactively calibrate and update the control parameters. This maintains the accuracy of airflow supply over the long term, ensuring the combustion system operates continuously, stably, and efficiently throughout its entire lifespan, reducing the risk of performance degradation or malfunction due to long-term use.

[0046] In some preferred embodiments, after updating the calibration parameter curve, the method further includes: determining whether the PWM duty cycle determined based on the updated calibration parameter curve at the maximum speed point exceeds a preset safety threshold; if the PWM duty cycle determined based on the updated calibration parameter curve exceeds the safety threshold, then controlling the combustion system to enter a shutdown protection state.

[0047] In practice, the controller reads the PWM duty cycle value corresponding to the maximum speed FH from the updated calibration parameter curve. Then, the controller compares this PWM duty cycle value with a pre-stored PWM duty cycle safety threshold representing the upper limit of safe fan operation. This safety threshold is set based on the physical limits and safety margins of the fan motor and drive circuit. If the comparison shows that the PWM duty cycle value corresponding to the updated maximum speed FH exceeds this safety threshold, the controller determines that the current flue resistance has increased abnormally (e.g., severe blockage of the flue), exceeding the system's ability to compensate safely through adjustment. At this point, the controller immediately generates a protection signal, controlling the combustion system to enter a complete shutdown protection state, cutting off the gas supply and stopping the fan operation, while simultaneously displaying a fault code on the operator.

[0048] This embodiment adds a crucial safety boundary check to the periodic learning process, providing ultimate safety assurance and preventing the system from making ineffective or even dangerous over-adjustments under abnormal conditions. When the flue is severely blocked, the learning algorithm may calculate that an extremely high PWM duty cycle is needed to drive the fan in order to maintain the theoretical airflow. If left unchecked, this could lead to long-term overload and overheating of the fan motor, damaging the fan or drive circuit and posing a safety hazard. By setting and checking safety thresholds, the system can proactively intervene and switch to shutdown protection before the control parameters are about to reach the hardware safety limits. This not only protects important hardware such as the fan from damage and extends the service life of the equipment, but more importantly, it avoids a dangerous operating condition: the system attempting to operate under conditions of severe flue blockage and extremely deteriorated combustion conditions, which could lead to incomplete combustion or other safety problems.

[0049] In some preferred embodiments, the method further includes: continuously monitoring the flame feedback current during combustion operation; when the fan runs to the minimum operating speed determined according to the calibration parameter curve, determining whether the current flame feedback current is less than a preset calibration current threshold; if the flame feedback current is less than the calibration current threshold, increasing the minimum operating speed of the fan and continuing to monitor the flame feedback current after increasing the speed until the flame feedback current is greater than or equal to the calibration current threshold.

[0050] In practice, during normal operation of the combustion system based on the updated calibration parameter curve, the controller continuously monitors the feedback current signal generated by flame ionization through the flame detection circuit. When the system operates at minimum load, i.e., the fan operates at the minimum operating speed according to the calibration parameter curve (this speed is determined by the control parameters corresponding to the FL point in the curve), the controller reads the flame feedback current value at this moment. The controller compares this flame feedback current value with a preset calibration current threshold representing the minimum ionization current required for stable small flame combustion. If the monitored flame feedback current is less than the calibration current threshold, it indicates that the current small flame combustion intensity is insufficient and in an unstable state, with a risk of flameout or resonance. At this time, the controller will initiate the minimum flame stabilization program: it first increases the minimum operating speed command value issued to the fan, slightly increasing the fan speed. Then, the system continues to closely monitor the flame feedback current after the speed increase. This "speed increase - current monitoring" cycle will continue until the monitored flame feedback current value rises to greater than or equal to the calibration current threshold. At this point, it is considered that the small flame combustion has returned to stability, and the system will continue to operate at this new, higher speed as the current actual minimum operating speed.

[0051] This embodiment provides an adaptive solution specifically addressing the technical challenge of unstable premixed combustion under low-fire (low-load) conditions. By real-time monitoring of the direct characteristic parameter of combustion status (flame ionization current), it dynamically adjusts the minimum airflow supply required to maintain stable combustion (achieved by increasing the fan speed). When the gas pressure temporarily drops, gas composition fluctuates, or other factors cause the low-fire flame to weaken, traditional fixed-speed control is inadequate and easily leads to flameout. This solution, through a feedback mechanism, actively increases the airflow (increasing the fan speed) the instant the flame weakens, essentially "supplementing oxygen" to the weak flame, thereby enhancing the combustion reaction and restoring flame stability. This effectively solves the defects of existing technologies where low-fire combustion may result in flameout or system resonance, significantly improving reliability and user experience during low-load operation and achieving stable combustion across the entire operating range.

[0052] In some preferred embodiments, increasing the minimum operating speed of the fan and continuing to monitor the flame feedback current after increasing the speed until the flame feedback current is greater than or equal to the calibrated current threshold specifically includes: increasing the minimum operating speed of the fan by a preset step value to obtain an adjusted speed; obtaining the flame feedback current at the adjusted speed; if the flame feedback current at the adjusted speed is greater than or equal to the calibrated current threshold, and the adjusted speed is less than or equal to a preset speed upper limit value, then setting the adjusted speed as the new minimum operating speed; if the flame feedback current at the adjusted speed is less than the calibrated current threshold, and the adjusted speed is less than the preset speed upper limit value, then proceeding to the step of increasing the minimum operating speed of the fan by a preset step value to obtain the adjusted speed.

[0053] In practice, when the minimum operating speed needs to be increased, the controller does not increase the speed drastically all at once, but rather adopts a gradual approximation method. The specific steps are as follows: First, the controller adds a preset, fixed or variable speed step size to the current minimum operating speed command value, thereby calculating an adjusted speed N1. Then, the system controls the fan to operate at this adjusted speed N1 and immediately acquires the flame feedback current I2. Next, the controller performs a dual condition check: first, it checks whether the newly acquired flame current I2 is greater than or equal to the calibrated current threshold I (calibration); second, it checks whether the current adjusted speed N1 is less than or equal to a preset speed upper limit value N (setting). Only when both conditions are met simultaneously does the system determine that a suitable stable point has been found and officially adopt the adjusted speed N1 as the new minimum operating speed. If the conditions are not met, i.e., the flame current I2 is still less than the calibrated threshold and the rotation speed N1 has not exceeded the upper limit value N (set), the system will repeat the above steps again: increase the value of N1 by one step to obtain a new N2, monitor the current I2 again and make a judgment, and so on, until the rotation speed point that simultaneously meets the requirements of flame stability and upper limit of rotation speed is found.

[0054] This embodiment provides a robust and controllable speed optimization algorithm, avoiding the blindness and oscillation risks of the adjustment process. By adopting a small step increment, the system can finely explore the minimum speed increment that can stabilize combustion, avoiding excessive adjustment that could cause the combustion state to exceed the stable range or cause unnecessary load increases. More importantly, in each iteration of adjustment, it simultaneously checks whether the speed exceeds a reasonable upper limit, limiting the process of finding the stable point to a safe operating range. This design ensures that the adjustment process is both effective (ultimately finding the stable point) and safe (not increasing the speed indefinitely and causing other problems). It achieves a balance between the two objectives of "solving small flame instability" and "preventing over-adjustment," making the entire minimum flame stabilization control process more reliable and accurate.

[0055] In some preferred embodiments, the method further includes: if the adjusted rotational speed is greater than or equal to the preset upper limit of rotational speed, then controlling the combustion system to enter a fault shutdown state.

[0056] In practice, during the cyclic adjustment process, each time the adjusted rotational speed (e.g., N1, N2...) is obtained and the flame current is checked to see if it meets the standard, it simultaneously checks whether the rotational speed exceeds the preset upper limit value N (set). If, after a certain iteration, the system detects that the adjusted rotational speed is greater than or equal to the preset upper limit value N (set), regardless of whether the monitored flame feedback current has reached the calibration threshold, the controller will immediately terminate the current adjustment cycle. At this point, the controller determines that the system cannot find an operating point within the safe and permissible rotational speed range that can stabilize the sprue flame. This usually indicates a more serious underlying fault, such as extremely low gas pressure, abnormal gas valve, or burner blockage. Accordingly, the controller will generate a fault signal, control the combustion system to enter a fault shutdown state, cut off the gas supply and stop operation, and simultaneously record and display the corresponding fault information.

[0057] This embodiment sets a final safety stop line for the minimum flame stabilization adjustment logic, providing fault diagnosis and protection functions. When the system attempts to stabilize the flame by increasing the rotation speed, but fails even after reaching the maximum safe limit, the system can make a clear fault determination, rather than endlessly trying or continuing to operate in an unstable state. This prevents the system from making unnecessary, potentially damaging, continuous high-speed operation attempts in abnormal situations (such as near-interruption of gas supply). More importantly, it identifies a "combustion instability state that cannot be repaired by conventional adjustments" as a clear system fault and takes shutdown protection measures. This prevents the equipment from continuing to operate under dangerous conditions (such as intermittent flameout and re-ignition), improving safety, and also provides users or maintenance personnel with a clear fault indication, facilitating subsequent troubleshooting and maintenance.

[0058] This invention proposes a fully premixed stable combustion control method, comprising: responding to a trigger signal, controlling a fan to enter a flue gas learning mode; in the flue gas learning mode, controlling the fan speed to gradually increase from a preset minimum speed to a preset maximum speed by adjusting the output PWM duty cycle of the fan; acquiring the actual PWM duty cycle of the fan at multiple different speed points; comparing the actual PWM duty cycle with the standard PWM duty cycle of the corresponding speed point in a pre-stored standard PWM duty cycle curve; adjusting the output PWM duty cycle of the fan at the current speed point according to the comparison result, such that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle; recording the output PWM duty cycle corresponding to each speed point after adjustment to form a calibration parameter curve under the current operating condition, and updating the standard PWM duty cycle curve to the calibration parameter curve, so as to control the fan speed according to the calibration parameter curve during subsequent combustion operation. This invention effectively solves the problem of combustion instability caused by differences in installation conditions through flue gas resistance self-learning and parameter adaptive calibration. In initialization learning mode, the system uses closed-loop regulation to ensure that the actual driving energy of the fan at each speed point is consistent with the standard operating condition, thereby offsetting the influence of actual flue resistance and generating personalized calibration parameter curves. This method ensures that the combustion system can maintain a precise air-fuel ratio and stable combustion state in various real-world environments, avoiding flameout, resonance, and backfire caused by inaccurate airflow, and achieving adaptive and reliable operation across the entire operating range.

[0059] Corresponding to the above-described fully premixed stable combustion control method, the present invention also provides a fully premixed stable combustion control device. This fully premixed stable combustion control device includes a unit for executing the above-described fully premixed stable combustion control method, and can be configured in a terminal or server. Specifically, the fully premixed stable combustion control device includes: The learning unit is used to control the fan to enter the flue learning mode in response to the trigger signal. In the flue learning mode, the fan speed is controlled to gradually increase from the preset minimum speed to the preset maximum speed by adjusting the output PWM duty cycle of the fan. The acquisition unit is used to acquire the actual PWM duty cycle of the fan at the current speed point for multiple different speed points; The comparison unit is used to compare the actual PWM duty cycle with the standard PWM duty cycle at the same speed point in the pre-stored standard PWM duty cycle curve; The adjustment unit is used to adjust the output PWM duty cycle of the fan at the current speed point according to the comparison result, so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle; The recording unit is used to record the output PWM duty cycle corresponding to each speed point after adjustment, form the calibration parameter curve under the current operating condition, and update the standard PWM duty cycle curve to the calibration parameter curve so as to control the speed of the fan according to the calibration parameter curve during subsequent combustion operation.

[0060] Optionally, adjusting the output PWM duty cycle of the fan at the current speed point based on the comparison result, so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle, includes: If the actual PWM duty cycle is less than the standard PWM duty cycle, then increase the output PWM duty cycle of the fan at the current speed point so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle; If the actual PWM duty cycle is greater than the standard PWM duty cycle, then the output PWM duty cycle of the fan at the current speed point is reduced so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle.

[0061] Optionally, it also includes: The update unit is used to return to the step of obtaining the actual PWM duty cycle of the fan at the current speed point for multiple different speed points when the cumulative running time of the combustion system reaches the preset learning cycle, so as to update the calibration parameter curve.

[0062] Optionally, it also includes a first security monitoring unit for: Determine whether the PWM duty cycle determined based on the updated calibration parameter curve at the maximum speed point exceeds a preset safety threshold. If the PWM duty cycle determined based on the updated calibration parameter curve exceeds the safety threshold, the combustion system is controlled to enter a shutdown protection state.

[0063] Optionally, it also includes a current monitoring unit for: During combustion operation, the flame feedback current is continuously monitored; When the fan runs to the minimum operating speed determined according to the calibration parameter curve, it is determined whether the current flame feedback current is less than the preset calibration current threshold. If the flame feedback current is less than the calibrated current threshold, the minimum operating speed of the fan is increased, and the flame feedback current after the speed is increased is monitored until the flame feedback current is greater than or equal to the calibrated current threshold.

[0064] Optionally, increasing the minimum operating speed of the fan and continuing to monitor the flame feedback current after increasing the speed until the flame feedback current is greater than or equal to the calibrated current threshold specifically includes: Increase the minimum operating speed of the fan by a preset step value to obtain the adjusted speed; Obtain the flame feedback current at the adjusted rotation speed; If the flame feedback current at the adjusted speed is greater than or equal to the calibrated current threshold, and the adjusted speed is less than or equal to the preset speed limit, then the adjusted speed is set as the new minimum operating speed. If the flame feedback current at the adjusted speed is less than the calibrated current threshold, and the adjusted speed is less than the preset upper speed limit, then proceed to the step of increasing the minimum operating speed of the fan by a preset step value to obtain the adjusted speed.

[0065] Optionally, a second security monitoring unit is also included, for: If the adjusted rotational speed is greater than or equal to the preset upper limit of rotational speed, the combustion system is controlled to enter a fault shutdown state.

[0066] It should be noted that those skilled in the art can clearly understand that the specific implementation process of the above-mentioned fully premixed stable combustion control device and each unit can be referred to the corresponding description in the foregoing method embodiments. For the sake of convenience and brevity, it will not be repeated here.

[0067] The aforementioned fully premixed stable combustion control device can be implemented as a computer program, which can, for example... Figure 2 It runs on the computer device shown.

[0068] Please see Figure 2 , Figure 2 This is a schematic block diagram of a computer device 500 provided in an embodiment of this application. The computer device 500 can be a terminal or a server.

[0069] The computer device 500 includes a processor 502, a memory, and a network interface 505 connected via a system bus 501. The memory may include a non-volatile storage medium 503 and internal memory 504.

[0070] The non-volatile storage medium 503 may store an operating system 5031 and a computer program 5032. When the computer program 5032 is executed, it causes the processor 502 to execute a fully premixed stable combustion control method.

[0071] The processor 502 provides computing and control capabilities to support the operation of the entire computer device 500.

[0072] The internal memory 504 provides an environment for the operation of the computer program 5032 in the non-volatile storage medium 503. When the computer program 5032 is executed by the processor 502, the processor 502 can execute a fully premixed stable combustion control method.

[0073] The network interface 505 is used for network communication with other devices. Those skilled in the art will understand that the above structure is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device 500 to which the present application is applied. A specific computer device 500 may include more or fewer components than shown in the figures, or combine certain components, or have different component arrangements.

[0074] The processor 502 is used to run a computer program 5032 stored in a memory to implement the steps of a fully premixed stable combustion control method provided in any of the above method embodiments.

[0075] It should be understood that in the embodiments of this application, the processor 502 may be a central processing unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0076] It will be understood by those skilled in the art that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program may be stored in a storage medium, which is a computer-readable storage medium. The computer program is executed by at least one processor in the computer system to implement the process steps of the embodiments of the above methods.

[0077] Therefore, the present invention also provides a storage medium. This storage medium may be a computer-readable storage medium. The storage medium stores a computer program. When executed by a processor, the computer program causes the processor to perform the steps of the fully premixed stable combustion control method provided in any of the above-described method embodiments.

[0078] The storage medium is a physical, non-transient storage medium, such as a USB flash drive, external hard drive, read-only memory (ROM), magnetic disk, or optical disk, or any other physical storage medium capable of storing program code. The computer-readable storage medium can be non-volatile or volatile.

[0079] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0080] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of each unit is merely a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0081] The steps in the method of this invention can be adjusted, merged, or reduced in order according to actual needs. The units in the device of this invention can be merged, divided, or reduced according to actual needs. Furthermore, the functional units in the various embodiments of this invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0082] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a terminal, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention.

[0083] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0084] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Since these modifications and variations fall within the scope of the claims and their equivalents, this invention also intends to include these modifications and variations.

[0085] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A fully premixed stable combustion control method, characterized in that, include: In response to a trigger signal, the fan is controlled to enter the flue learning mode. In the flue learning mode, the fan speed is controlled to gradually increase from the preset minimum speed to the preset maximum speed by adjusting the output PWM duty cycle of the fan. For multiple different speed points, obtain the actual PWM duty cycle of the fan at the current speed point; The actual PWM duty cycle is compared with the standard PWM duty cycle at the same speed point in the pre-stored standard PWM duty cycle curve; Based on the comparison results, the output PWM duty cycle of the fan at the current speed point is adjusted so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle. Record the output PWM duty cycle corresponding to each speed point after adjustment to form the calibration parameter curve under the current operating condition, and update the standard PWM duty cycle curve to the calibration parameter curve so as to control the speed of the fan according to the calibration parameter curve during subsequent combustion operation.

2. The fully premixed stable combustion control method according to claim 1, characterized in that, The step of adjusting the output PWM duty cycle of the fan at the current speed point based on the comparison result, so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle, includes: If the actual PWM duty cycle is less than the standard PWM duty cycle, then increase the output PWM duty cycle of the fan at the current speed point so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle; If the actual PWM duty cycle is greater than the standard PWM duty cycle, then the output PWM duty cycle of the fan at the current speed point is reduced so that the adjusted actual PWM duty cycle is equal to the standard PWM duty cycle.

3. The fully premixed stable combustion control method according to claim 1, characterized in that, The method further includes: When the cumulative running time of the combustion system reaches the preset learning cycle, the process returns to the step of obtaining the actual PWM duty cycle of the fan at the current speed point for multiple different speed points, so as to update the calibration parameter curve.

4. The fully premixed stable combustion control method according to claim 3, characterized in that, After updating the calibration parameter curve, the method further includes: Determine whether the PWM duty cycle determined based on the updated calibration parameter curve at the maximum speed point exceeds a preset safety threshold. If the PWM duty cycle determined based on the updated calibration parameter curve exceeds the safety threshold, the combustion system is controlled to enter a shutdown protection state.

5. The fully premixed stable combustion control method according to claim 1, characterized in that, The method further includes: During combustion operation, the flame feedback current is continuously monitored; When the fan runs to the minimum operating speed determined according to the calibration parameter curve, it is determined whether the current flame feedback current is less than the preset calibration current threshold. If the flame feedback current is less than the calibrated current threshold, the minimum operating speed of the fan is increased, and the flame feedback current after the speed is increased is monitored until the flame feedback current is greater than or equal to the calibrated current threshold.

6. The fully premixed stable combustion control method according to claim 5, characterized in that, The process of increasing the minimum operating speed of the fan and continuing to monitor the flame feedback current after increasing the speed until the flame feedback current is greater than or equal to the calibrated current threshold specifically includes: Increase the minimum operating speed of the fan by a preset step value to obtain the adjusted speed; Obtain the flame feedback current at the adjusted rotation speed; If the flame feedback current at the adjusted speed is greater than or equal to the calibrated current threshold, and the adjusted speed is less than or equal to the preset speed limit, then the adjusted speed is set as the new minimum operating speed. If the flame feedback current at the adjusted speed is less than the calibrated current threshold, and the adjusted speed is less than the preset upper speed limit, then proceed to the step of increasing the minimum operating speed of the fan by a preset step value to obtain the adjusted speed.

7. The fully premixed stable combustion control method according to claim 6, characterized in that, The method further includes: If the adjusted rotational speed is greater than or equal to the preset upper limit of rotational speed, the combustion system is controlled to enter a fault shutdown state.

8. A fully premixed stable combustion control device, characterized in that, Includes a unit for performing the method as described in any one of claims 1-7.

9. A computer device, characterized in that, The computer device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program that, when executed by a processor, can implement the method as described in any one of claims 1-7.

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