A self-adaptive control method and system for a full-premix gas heating and water heater

Abstract

This invention relates to the field of gas-fired heating and hot water boiler control technology, and provides an adaptive control method and system for a fully premixed gas-fired heating and hot water boiler. By real-time monitoring of the current opening command of the gas proportional valve and combining it with preset benchmark operating parameters to determine the opening command deviation, the changing trend of the opening command deviation is analyzed to accurately identify the performance degradation of the gas proportional valve. Based on this, a performance compensation factor is determined, and the current opening command is corrected according to this performance compensation factor, thereby achieving precise regulation of the gas supply. This solves the problems of reduced combustion efficiency, unstable heat output, and equipment failure caused by the performance degradation of the gas proportional valve, significantly improving the combustion efficiency, operational stability, and user experience of the fully premixed gas-fired heating and hot water boiler, extending the service life of the equipment, and reducing maintenance costs.

Description

Technical Field

[0001] This application relates to the field of gas-fired heating and hot water boiler control technology, and more specifically, to an adaptive control method and system for a fully premixed gas-fired heating and hot water boiler. Background Technology

[0002] Fully premixed gas-fired heating and hot water boilers achieve efficient combustion by adjusting the air-fuel ratio through a fan and a gas proportional valve. However, during long-term operation, impurities in the gas tend to deposit inside the proportional valve, forming grease and altering its mechanical and fluid properties. This leads to valve response delays, reduced actual opening, and gas flow rates lower than the set value. Since the system typically lacks a gas flow sensor, the controller cannot recognize this change and continues to mix air according to the original parameters, causing the actual air-fuel ratio to deviate, resulting in a lean combustion state. Lean combustion causes problems such as decreased combustion efficiency, insufficient output heat load, flame instability, and even flame lift-off or flameout. Existing adaptive control methods struggle to effectively compensate for this performance degradation of components.

[0003] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0004] This application discloses an adaptive control method and system for a fully premixed gas heating and hot water boiler, which aims to solve problems such as air-fuel ratio mismatch, reduced combustion efficiency, insufficient heat output, and unstable equipment operation caused by the performance degradation of key components such as the gas proportional valve during long-term operation of the fully premixed gas heating and hot water boiler.

[0005] The technical solution of this application is as follows:

[0006] In a first aspect, this application discloses an adaptive control method for a fully premixed gas-fired heating and hot water boiler. The heating and hot water boiler includes a gas proportional valve and a fan. The method includes:

[0007] The current opening command of the gas proportional valve is monitored in real time, and the opening command deviation is determined based on the current opening command and preset reference operating parameters.

[0008] Analyze the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve;

[0009] A performance compensation factor is determined based on the deviation of the flow characteristics; this performance compensation factor is used to indicate the rate and extent of performance degradation of the gas proportional valve.

[0010] Based on the performance compensation factor, the current opening command is modified to regulate and control the gas supply.

[0011] Furthermore, before real-time monitoring of the current opening command of the gas proportional valve, the method further includes: in the initial operating state of the heating hot water boiler, under the preset heat output demand, recording the correspondence between the fan speed and the reference opening command of the gas proportional valve, and storing it as a reference operating parameter; determining the opening command deviation based on the current opening command and the preset reference operating parameter includes: comparing the current opening command with the reference opening command corresponding to the same heat output demand in the reference operating parameter, and calculating the opening command deviation.

[0012] Based on this, the analysis of the changing trend of the opening command deviation is used to determine the deviation of the flow characteristics of the gas proportional valve. This includes: collecting opening command deviation data and storing it in the current sliding time window and removing outliers; calculating the weighted average of the opening command deviation data after removing outliers to obtain the weighted average command deviation of the current sliding time window; comparing the weighted average command deviation of the current sliding time window with the weighted average command deviation of the previous time window, and determining that the weighted average command deviation has an increasing trend, thus determining that the flow characteristics of the gas proportional valve have deviated.

[0013] Furthermore, a performance compensation factor is determined based on the deviation of the flow characteristics, including: using a linear regression algorithm to fit the average command deviation data within a historical preset time period to obtain the slope of the opening command deviation changing over time; and using the product of this slope and a sensitivity coefficient as the performance compensation factor.

[0014] In some preferred embodiments, before real-time monitoring of the current opening command of the gas proportional valve, the method further includes: in the initial operating state of the heating hot water boiler, under a preset heat output demand, recording the fan speed, reference opening command, flame ion current stability characteristics, flue gas temperature and actual heat output, and storing them as a combustion characteristic reference.

[0015] The analysis focuses on the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve. This includes: real-time monitoring of the current opening command, flame ion current stability characteristics, and exhaust temperature under the current heat output demand, and comparing them with the corresponding benchmark values ​​under the same heat output demand in the combustion characteristic benchmark, and calculating the opening command deviation, flame ion current characteristic deviation, and exhaust temperature deviation.

[0016] Based on long-term recorded opening command deviation, flame ion current characteristic deviation, and flue gas temperature deviation, combustion characteristic combination modes are identified; these combustion characteristic combination modes include gas proportional valve self-fading mode and fan or burner fading mode.

[0017] As a technical improvement, a performance compensation factor is determined based on the deviation of flow characteristics, including: in response to the combustion characteristic combination mode being the gas proportional valve self-fading mode, a linear regression algorithm is used to fit the average command deviation data within a historical preset time period to obtain the slope of the opening command deviation changing over time; the product of this slope and a sensitivity coefficient is used as the performance compensation factor.

[0018] To improve the scheme, the identification of combustion feature combination mode includes: if the linear regression slope of the opening command deviation is greater than the first preset threshold; at the same time, the ratio of the peak value to the average value of the power spectral density in the flame ion current feature deviation in the preset low frequency band is greater than the second preset threshold, and the average value of the exhaust gas temperature deviation is less than zero, and its absolute value is greater than the third preset threshold; then the combustion feature combination mode is determined to be the gas proportional valve self-fading mode.

[0019] As a further improvement, the method for identifying combustion feature combination modes also includes: if the linear regression slope of the opening command deviation is greater than a first preset threshold; and at the same time, the ratio of the peak value to the average value of the power spectral density in the flame ion current feature deviation within a preset low frequency band is less than or equal to a second preset threshold, and the average value of the exhaust gas temperature deviation is greater than a fourth preset threshold; then the combustion feature combination mode is determined to be a fan or burner degradation mode.

[0020] Based on the above, in the initial operating state of the heating hot water boiler, under the preset heat output demand, the fan speed, reference opening command, flame ion current stability characteristics, flue gas temperature, and actual heat output are recorded and stored as combustion characteristic references. This includes: in the initial operating state of the heating hot water boiler, operating at the preset heat output demand point, after the heating hot water boiler reaches and maintains a stable state at the preset heat output demand point, starting a continuous data acquisition window to acquire flame ion current signals and flue gas temperature data; performing frequency domain analysis on the flame ion current signal, calculating its power spectral density, and assessing whether there is abnormal concentration or significant peak in the energy distribution of the predetermined low-frequency band, and obtaining the power spectral density analysis results; calculating the instantaneous fluctuation amplitude of the flue gas temperature data, and judging whether the current combustion state is pure based on the power spectral density analysis results and the instantaneous fluctuation amplitude; in response to the purity of the current combustion state, recording the current gas proportional valve opening command, flame ion current signal, and flue gas temperature data as the reference opening command, flame ion current stability characteristics, and flue gas temperature for the heat output point, respectively, and storing them as combustion characteristic references.

[0021] Secondly, this application also discloses an adaptive control system for a fully premixed gas-fired heating and hot water boiler. The heating and hot water boiler includes a gas proportional valve and a fan. The system includes: a monitoring module for real-time monitoring of the current opening command of the gas proportional valve and determining the opening command deviation based on the current opening command and preset benchmark operating parameters; an analysis module for analyzing the changing trend of the opening command deviation to determine the flow characteristic deviation of the gas proportional valve; a compensation module for determining a performance compensation factor based on the flow characteristic deviation; the performance compensation factor is used to indicate the speed and degree of performance degradation of the gas proportional valve; and a control module for correcting the current opening command based on the performance compensation factor to regulate and control the gas supply.

[0022] Beneficial effects

[0023] This application discloses an adaptive control method for a fully premixed gas-fired heating and hot water boiler. By real-time monitoring of the current opening command of the gas proportional valve and combining it with preset benchmark operating parameters to determine the opening command deviation, this method can effectively capture the deviation in flow characteristics of the gas proportional valve caused by impurity deposition and other reasons during long-term operation. Furthermore, by analyzing the changing trend of the opening command deviation, this method accurately identifies the performance degradation of the gas proportional valve and determines a performance compensation factor accordingly. This factor quantifies the rate and extent of performance degradation of the gas proportional valve. Finally, the current opening command is corrected based on this performance compensation factor, thereby achieving precise regulation of the gas supply.

[0024] Through the above technical solution, this application overcomes the shortcomings of existing technologies that cannot identify and compensate for control mismatch caused by the deterioration of the physical characteristics of the gas proportional valve. When the performance of the gas proportional valve deteriorates, traditional control systems will suffer from insufficient gas supply, resulting in lean combustion, decreased combustion efficiency, insufficient heat output, increased combustion noise, and even shutdown. This application, by introducing a performance compensation factor, can dynamically adjust the opening command of the gas proportional valve. Even if the actual flow characteristics of the gas proportional valve change, it can ensure that the gas supply and the air volume provided by the fan are precisely matched, maintaining the optimal air-fuel ratio. Therefore, this application effectively solves the problems of reduced combustion efficiency, unstable heat output, and equipment failure caused by the performance degradation of the gas proportional valve, significantly improving the combustion efficiency, operational stability, and user experience of the fully premixed gas heating and hot water boiler, extending the service life of the equipment, and reducing maintenance costs. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating the steps of the adaptive control method for a fully premixed gas-fired heating and hot water boiler disclosed in an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the adaptive control system structure of the fully premixed gas heating and hot water boiler disclosed in an embodiment of the present invention. Detailed Implementation

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which these embodiments belong; the terminology used herein and in the specification of the application is for the purpose of describing particular embodiments only and is not intended to limit these embodiments; the terms "comprising" and "having," and any variations thereof, in the specification of these embodiments and the foregoing drawings, are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification of these embodiments and the foregoing drawings are used to distinguish different objects, not to describe a particular order.

[0028] The implementation details of the technical solution in this embodiment are described in detail below:

[0029] During long-term operation, the performance of key components such as the gas proportional valve in fully premixed gas-fired heating and hot water boilers gradually deteriorates due to the accumulation of impurities. This leads to a mismatch between the gas supply and control commands, resulting in air-fuel ratio imbalance, decreased combustion efficiency, insufficient heat output, unstable operation, and even shutdown. Traditional control systems struggle to detect and compensate for this gradual decline in component performance, preventing the equipment from maintaining optimal combustion conditions for extended periods.

[0030] To address this, this application proposes an adaptive control method for a fully premixed gas-fired heating and hot water boiler, which includes a gas proportional valve and a fan, such as... Figure 1 As shown, the method includes:

[0031] S101, Real-time monitoring of the current opening command of the gas proportional valve, and determination of the opening command deviation based on the current opening command and preset reference operating parameters;

[0032] S102, Analyze the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve;

[0033] S103, determine a performance compensation factor based on the deviation of the flow characteristics; the performance compensation factor is used to indicate the rate and extent of performance degradation of the gas proportional valve;

[0034] S104, Based on the performance compensation factor, correct the current opening command to adjust and control the gas supply.

[0035] This application introduces an adaptive sensing and compensation mechanism for the performance degradation of the gas proportional valve, which can effectively solve the control mismatch problem caused by component aging in the prior art, and ensure that the heating hot water boiler can maintain a high-efficiency and stable combustion state throughout its entire life cycle.

[0036] To better understand the technical solution proposed in this application, some key terms are explained first. A gas proportional valve is an actuator that precisely adjusts the gas flow rate based on electrical signals; its opening command directly determines the gas supply. A fan is responsible for providing the air required for combustion, and its speed is closely related to the air flow rate. Preset reference operating parameters refer to the correspondence between the gas proportional valve opening command and parameters such as fan speed under different heat output demands in the initial or ideal state of the heating / hot water boiler. These parameters serve as a reference for the normal operation of the equipment. Opening command deviation refers to the difference between the current gas proportional valve opening command and the reference opening command under the corresponding heat output demand in the reference operating parameters. Flow characteristic deviation refers to the deviation between the actual flow output of the gas proportional valve and its theoretical or initial calibrated flow characteristics, usually caused by internal wear, carbon buildup, or impurity deposition. The performance compensation factor is a quantitative indicator used to describe the speed and extent of performance degradation of the gas proportional valve; a larger value indicates more severe or faster degradation.

[0037] The core of the adaptive control method proposed in this application lies in the precise perception and compensation of performance degradation of the gas proportional valve. Specifically, this method first requires real-time monitoring of the current opening command of the gas proportional valve. For example, the current opening command can be obtained by reading the electrical signal sent to the gas proportional valve by the main controller of the heating and hot water boiler. This command can be a voltage signal, a current signal, or a digital signal, representing the degree to which the main controller expects the gas proportional valve to open. After obtaining the current opening command, the opening command deviation needs to be determined based on the command and preset benchmark operating parameters. For example, the current opening command can be compared with the benchmark operating parameters stored in the controller's memory. The benchmark operating parameters can be the correspondence between the fan speed and the benchmark opening command of the gas proportional valve, calibrated and recorded experimentally under different heat output requirements before the heating and hot water boiler leaves the factory or during initial installation. By comparing the opening command under the current operating state with the benchmark opening command under the same heat output requirements, the opening command deviation can be calculated.

[0038] Next, it is necessary to analyze the trend of the opening command deviation to determine if the flow characteristics of the gas proportional valve have deviated. For example, this can be done by continuously recording the opening command deviation data over a period of time and performing statistical analysis on this data. If the opening command deviation shows a continuous increasing or decreasing trend, it indicates that the flow characteristics of the gas proportional valve may have deviated. This deviation may be due to mechanical wear, carbon deposits, or impurity deposition inside the valve, causing the actual flow output of the gas proportional valve to differ from the expected flow under the same control command.

[0039] After determining that the gas proportional valve has a deviation in flow characteristics, a performance compensation factor needs to be determined based on this deviation. For example, this compensation factor can be calculated based on the rate of change or cumulative amount of the opening command deviation. The performance compensation factor is a dynamically adjusted value that quantifies the speed and extent of the gas proportional valve's performance degradation. For instance, if the opening command deviation continues to increase at a rapid rate, the performance compensation factor will increase accordingly to reflect the rapid performance degradation of the gas proportional valve.

[0040] Finally, based on the determined performance compensation factor, the current opening command is corrected to regulate and control the gas supply. For example, if the performance compensation factor indicates that the actual flow output of the gas proportional valve is too low, a compensation amount can be added to the original opening command sent by the main controller to the gas proportional valve, making the gas proportional valve open to a greater extent, thereby compensating for insufficient gas supply caused by performance degradation. In this way, even if the performance of the gas proportional valve deteriorates, the control system of the heating and hot water boiler can adaptively adjust the gas supply to ensure that the air-fuel ratio is maintained at the optimal state, thereby ensuring combustion efficiency and equipment stability.

[0041] The overall working principle of this application lies in constructing a closed-loop adaptive control mechanism to address the inevitable performance degradation of gas proportional valves during long-term operation. When the heating boiler is running, the control system monitors the current opening command of the gas proportional valve in real time. This command is calculated by the main controller and sent to the gas proportional valve based on the current heat output demand. Simultaneously, the system references preset baseline operating parameters, which represent the performance curve of the gas proportional valve under ideal conditions. By comparing the current opening command with the baseline opening command corresponding to the heat output demand in the baseline operating parameters, the system can calculate the opening command deviation.

[0042] This opening command deviation is an initial signal of performance degradation in the gas proportional valve. For example, if the actual flow rate of the gas proportional valve decreases under the same command due to internal carbon buildup, the main controller needs to issue a larger opening command to achieve the preset heat output, thus increasing the opening command deviation. The system continuously analyzes the changing trends of these opening command deviations. By accumulating and analyzing historical data, such as comparing weighted averages within a sliding time window, the system can identify whether the opening command deviation shows a continuous increasing or decreasing trend, thereby determining whether the gas proportional valve has a deviation in flow characteristics.

[0043] Once a deviation in flow characteristics is confirmed, the system determines a performance compensation factor based on the degree and speed of the deviation. This compensation factor quantifies the performance degradation of the gas proportional valve, reflecting the difference between the valve's actual flow output and theoretical flow output. For example, if the flow characteristic deviation is severe and rapid, the compensation factor will be correspondingly larger. Finally, the system uses this performance compensation factor to correct the current opening command issued by the main controller. The corrected command is sent to the gas proportional valve, enabling it to output a gas flow rate closer to the ideal state, taking into account its own performance degradation. For example, if the compensation factor indicates that the gas proportional valve needs a larger opening to achieve the target flow rate, the corrected command will increase the opening accordingly. Through this series of steps, this application achieves adaptive compensation for the performance degradation of the gas proportional valve, ensuring precise mixing of gas and air, thereby maintaining efficient and stable combustion of the heating boiler throughout its entire life cycle.

[0044] The adaptive control method for fully premixed gas-fired heating and hot water boilers proposed in this application has significant advantages and innovations compared to existing technologies. Traditional control systems typically rely on fixed parameters set at the factory or simple adaptive logic. While these systems can cope with changes in the external environment (such as atmospheric pressure), they are ineffective against the physical performance degradation of critical internal components of the boiler, particularly the gas proportional valve, caused by long-term operation. When the flow characteristics of the gas proportional valve deviate due to impurity deposits, existing systems cannot detect this internal change and continue to supply gas according to the original instructions. This leads to an imbalance in the air-fuel ratio, causing a series of problems such as decreased combustion efficiency, insufficient heat output, and even shutdown failures.

[0045] The core innovation of this application lies in the introduction of an adaptive sensing and compensation mechanism for the performance degradation of a gas proportional valve. By monitoring the current opening command of the gas proportional valve in real time and comparing it with preset benchmark operating parameters, the deviation of the opening command can be accurately determined. More importantly, this application further analyzes the changing trend of the opening command deviation, thereby identifying the deviation of the gas proportional valve's flow characteristics. This step is not available in existing technologies, enabling the system to "diagnose" the "health status" of the gas proportional valve. Based on this, this application determines a performance compensation factor according to the flow characteristic deviation, which can quantify the speed and extent of the gas proportional valve's performance degradation. Finally, this performance compensation factor is used to correct the current opening command, thereby achieving precise regulation of the gas supply.

[0046] For example, in existing technologies, when the gas proportional valve experiences a 10% reduction in gas flow rate under the same opening command due to grease buildup, the controller still issues the original command, resulting in insufficient actual gas supply, a lean air-fuel ratio, and reduced combustion efficiency. The method of this application, however, can identify the deviation in the gas proportional valve's flow characteristics by observing the continuously increasing trend of the opening command deviation and calculate the corresponding performance compensation factor. For example, this compensation factor might indicate that the opening command needs to be increased by 10% to achieve the expected gas flow rate. With the corrected opening command, the gas proportional valve can actually open to a greater extent, thereby compensating for the flow loss caused by performance degradation, ensuring precise matching of gas supply and air volume, and maintaining the optimal air-fuel ratio.

[0047] Therefore, this application not only solves the control mismatch problem caused by component aging in the prior art, but more importantly, it provides a forward-looking and adaptive solution that enables the heating and hot water boiler to maintain a high-efficiency and stable combustion state throughout its entire life cycle, regardless of changes in the performance of the gas proportional valve, thus significantly improving the reliability, energy efficiency and user experience of the equipment.

[0048] This application further proposes a more accurate and reliable method for obtaining reference operating parameters and calculating deviations to improve the accuracy and robustness of adaptive control. In the aforementioned adaptive control method for a fully premixed gas-fired heating and hot water boiler, before real-time monitoring of the current opening command of the gas proportional valve, the method further includes: in the initial operating state of the heating and hot water boiler, under a preset heat output demand, recording the correspondence between the fan speed and the reference opening command of the gas proportional valve, and storing this as reference operating parameters; determining the opening command deviation based on the current opening command and the preset reference operating parameters includes: comparing the current opening command with the reference opening command corresponding to the same heat output demand in the reference operating parameters, and calculating the opening command deviation.

[0049] Specifically, the "initial operating state" refers to the stable operating stage of the heating and hot water boiler after its initial installation, commissioning, or major maintenance. At this point, the performance of each component of the boiler is at or near its optimal state. In this state, the boiler is operated at different "preset heat output demand" points (e.g., set to 30%, 50%, 80% of the rated power output), and the "fan speed" and corresponding "gas proportional valve reference opening command" required to maintain stable combustion are recorded for each heat output demand. These recorded correspondences are "stored as reference operating parameters," forming a reference dataset reflecting the performance of the heating and hot water boiler under ideal conditions. The "reference opening command" refers to the ideal opening degree that the gas proportional valve should achieve to achieve stable combustion under a specific heat output demand. During subsequent operation, when it is necessary to "determine the opening command deviation based on the current opening command and preset benchmark operating parameters," the specific method is to compare the real-time monitored "current opening command" with the "benchmark opening command" in the "benchmark operating parameters" that corresponds to the current "heat output demand," thereby accurately "calculating the opening command deviation." This comparison ensures that the deviation calculation is performed under the same operating conditions, eliminating opening differences caused by changes in heat output demand.

[0050] This application's solution establishes a precise performance baseline for a specific heating water boiler by systematically recording the correspondence between fan speed and the reference opening command of the gas proportional valve during the initial operation of the boiler, and storing this data as a reference operating parameter. Because this baseline is based on the boiler's optimal performance state, it accurately reflects the flow characteristics of the gas proportional valve under ideal operating conditions. In subsequent operation, by comparing the real-time monitored current opening command with the reference opening command corresponding to the same heat output demand in this reference operating parameter, the influence of different heat output demands can be eliminated, allowing the calculated opening command deviation to more accurately indicate the actual performance deviation of the gas proportional valve. This baseline, established based on actual operating data, makes deviation calculation more targeted and reliable, providing a solid foundation for subsequent flow characteristic deviation analysis and performance compensation.

[0051] Through the above technical solution, this application can establish a highly accurate and personalized benchmark operating parameter, effectively solving the problems of insufficient universality or inaccuracy that may exist in the preset benchmark parameters of traditional methods. Therefore, when determining the opening command deviation, a more precise comparison can be achieved, allowing the calculated opening command deviation to more accurately reflect the performance degradation of the gas proportional valve. This precise deviation calculation further improves the accuracy of subsequent flow characteristic deviation analysis, and ultimately enables the performance compensation factor to more effectively correct the gas supply, significantly improving the accuracy and reliability of the adaptive control of the fully premixed gas heating and hot water boiler, extending the service life of the equipment, and optimizing combustion efficiency.

[0052] In some preferred embodiments, a specific example is given below. Assume a brand-new, fully premixed gas-fired heating and hot water boiler enters its initial operating state after initial installation and commissioning. To establish its baseline operating parameters, the system can operate according to preset heat output demand points, for example, setting the boiler to operate stably at 30%, 50%, and 80% of its rated heat output power. When the boiler is stably operating at 30% heat output demand, the system records the fan speed as N1 and the gas proportional valve opening command as K1. When the boiler is stably operating at 50% heat output demand, the system records the fan speed as N2 and the gas proportional valve opening command as K2. When the boiler is stably operating at 80% heat output demand, the system records the fan speed as N3 and the gas proportional valve opening command as K3. These data (e.g., (30%, N1, K1), (50%, N2, K2), (80%, N3, K3)) are stored as the baseline operating parameters of the boiler. In subsequent daily operation, if the heating boiler is instructed to operate at 50% of its heat output demand, the system will monitor the current opening command of the gas proportional valve in real time. Let's assume the monitored current opening command is K_current. The system compares K_current with the baseline opening command K2 corresponding to 50% heat output demand in the baseline operating parameters, and calculates the opening command deviation ΔK = K_current - K2. This deviation ΔK will serve as the basis for subsequent analysis of the gas proportional valve's flow characteristic deviation.

[0053] Specifically, the above-mentioned analysis of the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve may include the following steps: The analysis of the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve includes: collecting opening command deviation data and storing it in the current sliding time window and removing outliers; calculating a weighted average value of the opening command deviation data after removing outliers to obtain the weighted average command deviation of the current sliding time window; comparing the weighted average command deviation of the current sliding time window with the weighted average command deviation of the previous time window, and determining that the weighted average command deviation has an increasing trend, then determining that the flow characteristics of the gas proportional valve have deviated.

[0054] The process of collecting and storing opening command deviation data within the current sliding time window and removing outliers involves continuously acquiring opening command deviation data of the gas proportional valve during the operation of the heating and hot water boiler, and then aggregating this data into a preset sliding time window. To ensure the accuracy and reliability of the data, outlier detection and removal are necessary. This can be achieved through statistical methods (such as the three-standard-deviation method) or methods based on physical constraints to identify and remove data points that significantly deviate from the normal range. The aim is to eliminate the impact of transient interference or measurement errors on subsequent analysis.

[0055] Furthermore, a weighted average is calculated on the opening command deviation data after outlier removal to obtain the weighted average command deviation for the current sliding time window. This means that after removing outliers, a weighted average is calculated on the remaining opening command deviation data within the current sliding time window. The weighted average can be calculated based on the data's age, reliability, or other preset weights. For example, newer data can be given a higher weight to better reflect the current system state. By calculating the weighted average, data fluctuations can be smoothed, the impact of random noise can be reduced, and more representative command deviation trend information can be obtained.

[0056] Therefore, by comparing the weighted average command deviation of the current sliding time window with the weighted average command deviation of the previous time window, and determining that the weighted average command deviation shows an increasing trend, it is determined that the flow characteristics of the gas proportional valve have deviated. This means comparing the weighted average command deviation calculated for the current sliding time window with the weighted average command deviation of one or more previous sliding time windows. If a continuous or significant increasing trend in the weighted average command deviation is observed, it indicates that the actual flow characteristics of the gas proportional valve may have deviated from its baseline state. That is, under the same heat output demand, a larger opening command is required to maintain combustion, which is usually a manifestation of performance degradation of the gas proportional valve.

[0057] This application's solution effectively handles noise and instantaneous fluctuations in real-time acquired opening command deviation data by introducing a sliding time window, outlier removal, and weighted average calculation. By performing trend analysis on the processed opening command deviation data, particularly comparing the current weighted average command deviation with historical time windows, early signs of flow characteristic deviation in the gas proportional valve can be accurately and stably identified. This method avoids misjudgments caused by fluctuations in a single data point, improving the robustness and accuracy of judging the performance degradation trend of the gas proportional valve. When a continuously increasing trend in the opening command deviation is detected, it indicates that the flow characteristics of the gas proportional valve have deviated, requiring a larger opening to achieve the expected gas supply, thus providing a reliable basis for subsequent performance compensation.

[0058] The above technical solution effectively filters out instantaneous interference and measurement noise in the opening command deviation data, improving the accuracy and stability of data analysis. By judging the trend of the weighted average command deviation, deviations in the flow characteristics of the gas proportional valve can be identified earlier and more reliably, avoiding misjudgments or delayed judgments caused by data fluctuations. This enables the adaptive control system of the heating and hot water boiler to respond more promptly to the performance degradation of the gas proportional valve, thereby ensuring combustion efficiency and system operational stability, and extending equipment lifespan.

[0059] This application further proposes a step for determining a performance compensation factor based on the above-mentioned flow characteristic deviation, including: using a linear regression algorithm to fit the average command deviation data within a historical preset time period to obtain the slope of the opening command deviation changing over time; and using the product of the slope and a sensitivity coefficient as the performance compensation factor.

[0060] Specifically, the linear regression algorithm is a statistical method used to establish a linear relationship model between a dependent variable (in this case, the opening command deviation) and one or more independent variables (in this case, time). This algorithm allows analysis of the trend of the opening command deviation data over time. The average command deviation data within a preset historical time period refers to a data sequence formed by averaging the collected opening command deviation data over a past period. Its purpose is to smooth data fluctuations and more accurately reflect the long-term performance trend of the gas proportional valve. The fitting process refers to using the linear regression algorithm to find an optimal fitting straight line to describe the change pattern of the average command deviation data over time. Thus, the slope of the opening command deviation over time can be obtained, which directly reflects the rate of performance degradation of the gas proportional valve. The sensitivity coefficient is a preset adjustment parameter used to convert the slope into a performance compensation factor with practical physical meaning. Its purpose is to appropriately adjust the quantification of performance degradation based on actual operating conditions and experience.

[0061] This application's solution, by introducing a linear regression algorithm, transforms the qualitative judgment of the flow characteristic deviation of a gas proportional valve into a quantitative analysis. Specifically, when the performance of a gas proportional valve deteriorates, its opening command deviation under the same heat output demand will exhibit a certain trend. By performing linear regression fitting on the average command deviation data over a preset historical period, the slope of the opening command deviation over time can be accurately calculated. This slope directly quantifies the rate of performance degradation of the gas proportional valve, i.e., the increase in opening command deviation per unit time. Furthermore, multiplying this slope by a preset sensitivity coefficient yields a comprehensive performance compensation factor. This performance compensation factor not only indicates the rate of performance degradation but also reflects the degree of degradation through the adjustment of the sensitivity coefficient, thus providing a precise quantitative basis for subsequent command correction.

[0062] In some preferred embodiments, it is assumed that during the operation of the heating hot water boiler, the system records the average opening command deviation data of the gas proportional valve at regular intervals (e.g., daily). For example, the average opening command deviation data recorded over the past 30 days are D1, D2, ..., D30. To determine the performance compensation factor, the system calls a linear regression algorithm, using time (e.g., days 1 to 30) as the independent variable and the average opening command deviation data (D1 to D30) as the dependent variable, to perform a fitting. Through fitting, a linear equation can be obtained: Deviation = Slope * Time + Intercept. The calculated slope is the slope of the opening command deviation changing over time. For example, if the calculated slope is 0.05% / day, it means that the opening command deviation of the gas proportional valve increases by an average of 0.05% per day. Subsequently, multiplying this slope (0.05) by a preset sensitivity coefficient (e.g., set to 2) yields a performance compensation factor of 0.1. The performance compensation factor of 0.1 will be used to correct the current opening command to compensate for the performance degradation of the gas proportional valve and ensure the accuracy of gas supply.

[0063] This application further proposes a more refined adaptive control method for fully premixed gas heating and hot water boilers. By introducing the monitoring and analysis of multi-dimensional combustion characteristic parameters, it can more accurately identify the deviation of the flow characteristics of the gas proportional valve and distinguish different combustion system degradation modes.

[0064] In some embodiments of this application, the above-mentioned fully premixed gas heating and hot water boiler adaptive control method further includes, before real-time monitoring of the current opening command of the gas proportional valve: in the initial operating state of the heating and hot water boiler, under the preset heat output demand, recording the fan speed, reference opening command, flame ion current stability characteristics, flue gas temperature and actual heat output, and storing them as combustion characteristic references.

[0065] The analysis of the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve includes:

[0066] Real-time monitoring of the current opening command, flame ion current stability characteristics, and exhaust temperature under the current heat output demand, and comparison with the corresponding benchmark values ​​under the same heat output demand in the combustion characteristic benchmark, and calculation of opening command deviation, flame ion current characteristic deviation, and exhaust temperature deviation;

[0067] Based on long-term recorded deviations in opening commands, flame ion current characteristics, and exhaust temperature, combustion characteristic combination modes are identified; these combustion characteristic combination modes include gas proportional valve self-fading mode and fan or burner fading mode.

[0068] Specifically, in the initial operating state of the heating hot water boiler—that is, after the equipment has just been put into use or after comprehensive maintenance and calibration—the system will run stably for a period of time at the preset heat output demand point to ensure that the combustion state reaches stability. During this stable state, a series of key operating parameters are recorded, including fan speed, the reference opening command of the gas proportional valve, flame ion current stability characteristics, flue gas temperature, and actual heat output. These parameters are comprehensively stored as a combustion characteristic benchmark, serving as a reference benchmark for subsequent operating state evaluation. Among these, the flame ion current stability characteristics can be understood as the stability and characteristics of the flame signal detected by the flame ion probe, such as its average value, fluctuation range, or frequency domain characteristics. These characteristics reflect the stability of combustion, the intensity and shape of the flame. Flue gas temperature refers to the temperature at which combustion products leave the boiler; its changes can indicate combustion efficiency, heat exchange status, or abnormal airflow. Actual heat output refers to the actual heat energy provided by the heating hot water boiler under specific operating conditions, which can be calculated from the water flow rate and the inlet and outlet water temperature difference.

[0069] Furthermore, during the daily operation of the heating and hot water boiler, the system monitors in real time the current operating degree command, flame ion current stability characteristics, and flue gas temperature under the current heat output demand. This real-time monitored data is compared with the baseline values ​​corresponding to the same heat output demand point in a pre-stored combustion characteristic benchmark. Through this comparison, the deviations in the operating degree command, flame ion current characteristics, and flue gas temperature can be calculated. These deviations reflect the differences between the current operating state and the initial healthy state.

[0070] Based on this, the solution in this application identifies combustion characteristic combination patterns using specific algorithms or models, based on long-term recorded data on opening command deviation, flame ionization current characteristic deviation, and flue gas temperature deviation. These combustion characteristic combination patterns aim to distinguish different types of system degradation or failure. Specifically, the combustion characteristic combination patterns include gas proportional valve self-degradation patterns and fan or burner degradation patterns. Gas proportional valve self-degradation patterns refer to a decline in the performance of the gas proportional valve itself, such as valve wear, sluggish response, or changes in flow characteristics. Fan or burner degradation patterns may refer to a decline in fan performance (such as insufficient speed or reduced airflow) or problems such as burner blockage or carbon buildup.

[0071] The solution presented in this application can more accurately determine the deviation of the flow characteristics of the gas proportional valve and distinguish different decay modes because it introduces multi-dimensional combustion characteristic parameters for comprehensive analysis. Traditional methods rely solely on the opening command deviation. When system problems occur, such as insufficient air supply due to fan performance degradation, the system may increase the opening command of the gas proportional valve to maintain the preset heat output, thus generating an opening command deviation. In this case, relying solely on the opening command deviation may misjudge it as gas proportional valve degradation itself. However, by simultaneously monitoring the stability characteristics of the flame ion current and the flue gas temperature, richer diagnostic information can be provided. For example, when insufficient gas supply is caused by gas proportional valve degradation, the system will attempt to increase the opening command to compensate. At this time, the flame ion current may exhibit unstable fluctuations or a decrease in intensity, while the flue gas temperature may decrease due to incomplete combustion. Conversely, if insufficient air supply is caused by fan performance degradation, the system will also increase the gas proportional valve opening command, but at this time, the flame ion current may exhibit characteristics of oxygen-rich or oxygen-deficient combustion, and the flue gas temperature may increase due to decreased combustion efficiency. By recording and recognizing these multidimensional deviation data over a long period, the system can establish characteristic fingerprints under different degradation modes, thereby accurately distinguishing whether the problem lies with the gas proportional valve itself, or with the fan or burner. This comprehensive analysis avoids the limitations of judging based on a single parameter and improves the accuracy of fault diagnosis.

[0072] Through the above technical solution, this application can accurately identify the degradation mode of the combustion system of a heating hot water boiler, especially in distinguishing between the degradation of the gas proportional valve itself and the degradation of the fan or burner. This multi-parameter, multi-dimensional data acquisition and pattern recognition method enables the system to more accurately determine whether the deviation of the flow characteristics of the gas proportional valve is indeed caused by its own performance degradation, thereby avoiding misjudgments caused by failures of other components. Therefore, targeted performance compensation or fault warnings can be performed, improving the accuracy and reliability of adaptive control, extending the service life of the heating hot water boiler, and ensuring its long-term combustion efficiency and safety.

[0073] In some preferred embodiments, a specific example is given below. Assume that the heating water boiler, in its initial operating state, at a preset heat output demand point, records the fan speed as N0, the baseline opening command as V0, the flame ion current stability characteristic as F0, the flue gas temperature as T0, and the actual heat output as Q0. After a period of operation, under the same heat output demand, the system monitors in real time that the current opening command is V1, the flame ion current stability characteristic is F1, and the flue gas temperature is T1. At this time, the opening command deviation ΔV = V1 - V0, the flame ion current characteristic deviation ΔF = F1 - F0, and the flue gas temperature deviation ΔT = T1 - T0 are calculated. If long-term records show that the opening command deviation ΔV continuously increases, while the flame ion current characteristic deviation ΔF shows a significant increase in the ratio of peak to average power spectral density within a preset low-frequency range (indicating decreased flame stability), and the average value of the exhaust gas temperature deviation ΔT is less than zero but its absolute value is greater than a certain threshold (indicating incomplete combustion leading to a decrease in exhaust gas temperature), then the system can identify the current combustion characteristic combination mode as a self-fading mode of the gas proportional valve. This means that the flow characteristics of the gas proportional valve have deviated, requiring a larger opening to achieve the same gas supply. Conversely, if the opening command deviation ΔV also continuously increases, but the flame ion current characteristic deviation ΔF shows no significant change or a decrease in the ratio of peak to average power spectral density within a preset low-frequency range, while the average value of the exhaust gas temperature deviation ΔT is significantly greater than a certain threshold (indicating decreased combustion efficiency or insufficient airflow leading to an increase in exhaust gas temperature), then the system can identify the current combustion characteristic combination mode as a fan or burner decay mode. In this case, although the opening command deviation exists, the root cause is not the gas proportional valve itself, but a problem with the fan or burner. Through this comprehensive analysis of multiple parameters, the system can accurately diagnose the root cause of the fault, thereby adopting more precise adaptive control strategies or issuing targeted maintenance suggestions.

[0074] Furthermore, this application proposes to determine a performance compensation factor based on the above-mentioned flow characteristic deviation, including: in response to the combustion characteristic combination mode being a gas proportional valve self-fading mode, using a linear regression algorithm to fit the average command deviation data within a historical preset time period to obtain the slope of the opening command deviation changing over time; and using the product of the slope and a sensitivity coefficient as the performance compensation factor.

[0075] Specifically, when the system analyzes the combination of combustion characteristics such as opening command deviation, flame ion current characteristic deviation, and flue gas temperature deviation, and clearly identifies that the current heating and hot water boiler is in a self-decay mode of the gas proportional valve, it indicates that the flow characteristics of the gas proportional valve are deviating, and this deviation mainly stems from the performance degradation of the gas proportional valve itself. At this point, to accurately quantify this degradation, a linear regression algorithm is used. Linear regression is a statistical method used to model the relationship between two or more variables, particularly to predict how a dependent variable (in this case, opening command deviation) changes with one or more independent variables (in this case, time). The historical preset time period refers to a pre-defined time cycle, such as the past week, month, or longer, used to collect sufficient data for effective trend analysis. The average command deviation data refers to the data obtained by averaging the collected opening command deviations at each time point or time period to eliminate instantaneous fluctuations and noise, and to more accurately reflect long-term trends. By linearly fitting these average command deviation data, the slope of the opening command deviation over time can be obtained. This slope directly reflects the rate of performance degradation of the gas proportional valve, that is, the rate at which the opening command deviation increases over time. Furthermore, the product of the slope and a sensitivity coefficient is used as the performance compensation factor. The sensitivity coefficient is an adjustable parameter used to adjust the response intensity of the compensation factor, enabling it to better adapt to the characteristics of different heating and hot water boilers or the user's requirements for compensation speed. The performance compensation factor is used to indicate the rate and extent of performance degradation of the gas proportional valve, providing a quantitative basis for subsequent correction of the current opening command.

[0076] This application's solution, by clearly identifying the self-fading mode of the gas proportional valve, introduces a linear regression algorithm to fit historical average command deviation data, thereby accurately quantifying the performance degradation rate of the gas proportional valve. Traditional judgments based solely on current or short-term deviation trends may fail to accurately capture long-term and stable degradation patterns. Linear regression, by analyzing data over a period of time, effectively filters out short-term fluctuations, revealing the inherent linear trend of the opening command deviation over time—that is, the slope of the degradation. It is precisely this precise quantification of the degradation rate that allows the determined performance compensation factor to more accurately reflect the actual degree of degradation of the gas proportional valve, thus providing a more reliable and refined basis for subsequent gas supply regulation.

[0077] Through the above technical solution, this application can specifically address the quantitative problem of performance degradation in gas proportional valves. By employing a linear regression algorithm to fit historical average command deviation data and combining it with a sensitivity coefficient to generate a performance compensation factor, this compensation factor can more accurately and stably indicate the rate and extent of performance degradation in the gas proportional valve. Compared to compensation based solely on general flow characteristic deviations, this significantly improves the accuracy and relevance of the compensation, avoiding over- or under-compensation, thereby ensuring the stability and safety of combustion efficiency in the heating and hot water boiler during long-term operation and extending the equipment's service life.

[0078] In some preferred embodiments, a specific example is given below. Assume that after the heating boiler has been running for a period of time, the system identifies that it is currently in the self-fading mode of the gas proportional valve by analyzing the combination of combustion characteristics. At this time, the system will initiate the collection and analysis of historical average command deviation data. For example, over the past 30 days, the system records the average opening command deviation of the gas proportional valve once a day. This data is stored to form a time series dataset. Subsequently, a linear regression algorithm is used to fit the average command deviation data of these 30 days. Assume that the fitting result shows that the slope of the opening command deviation changes with time is 0.01% per day, which means that the opening command deviation of the gas proportional valve increases by an average of 0.01% per day. Further, a sensitivity coefficient of 1.5 is preset. Then, according to this embodiment, the performance compensation factor will be calculated as: 0.01% (slope) × 1.5 (sensitivity coefficient) = 0.015. This performance compensation factor of 0.015 is then used to correct the current gas proportional valve opening command. For example, if the current opening command is 50%, the corrected command may become 50% + 0.015 = 50.015% to compensate for insufficient flow caused by the gas proportional valve decay, thereby maintaining the expected heat output.

[0079] In some embodiments of this application described above, to more accurately identify combustion feature combination patterns, this application further proposes specific judgment conditions. Specifically, the identification of combustion feature combination patterns may include the following steps: if the linear regression slope of the opening command deviation is greater than a first preset threshold; simultaneously, the ratio of the peak value to the average value of the power spectral density in the flame ion current characteristic deviation within a preset low-frequency band is greater than a second preset threshold, and the average value of the exhaust gas temperature deviation is less than zero, and its absolute value is greater than a third preset threshold; then the combustion feature combination pattern is determined to be a gas proportional valve self-fading mode.

[0080] The linear regression slope of the opening command deviation refers to the slope value obtained by performing linear regression analysis on historical opening command deviation data. This slope reflects the trend and speed of the gas proportional valve's opening command change over time under the same heat output demand. The first preset threshold is an empirical value or a critical value determined through experiments, used to determine whether the increasing trend of the opening command deviation is significant. The ratio of the peak value to the average value of the power spectral density in the flame ion current characteristic deviation within a preset low-frequency band is used to quantify the degree of fluctuation in flame stability during combustion. The preset low-frequency band typically corresponds to the frequency range of combustion instability or oscillation. The second preset threshold is used to determine whether the low-frequency fluctuation of the flame ion current signal reaches a level indicating a problem with the gas proportional valve. The average value of the exhaust temperature deviation refers to the average value of the difference between the actual exhaust temperature and the reference exhaust temperature. If it is less than zero and its absolute value is greater than the third preset threshold, it indicates that the exhaust temperature is significantly lower than the normal level, which may be related to insufficient gas supply or decreased combustion efficiency. The third preset threshold is used to define the significance of the exhaust temperature deviation. When all the above conditions are met simultaneously, the system can accurately identify the self-fading mode of the gas proportional valve.

[0081] This application's solution, through comprehensive analysis of multiple key combustion characteristic parameters, can accurately identify the self-decay mode of a gas proportional valve. When the gas proportional valve experiences performance degradation, in order to maintain the same heat output, the control system typically instructs the gas proportional valve to open to a larger degree, resulting in a continuously increasing trend in the opening command deviation, with its linear regression slope exceeding a first preset threshold. Simultaneously, the degradation of the gas proportional valve may lead to unstable gas supply, thereby affecting flame stability and causing abnormal peaks in the flame ion current signal in the low-frequency band; that is, the ratio of the peak value to the average value of the power spectral density in the preset low-frequency band will be greater than a second preset threshold. Furthermore, insufficient gas supply or decreased combustion efficiency may lead to incomplete combustion, resulting in exhaust gas temperature below normal levels, manifested as an average exhaust gas temperature deviation less than zero and its absolute value greater than a third preset threshold. By comprehensively judging these three interrelated indicators, this application can effectively eliminate interference from other factors (such as fan or burner degradation), thereby accurately pinpointing the performance degradation problem of the gas proportional valve itself.

[0082] Through the above technical solution, this application can accurately identify the self-fading mode of the gas proportional valve. This multi-dimensional, multi-parameter comprehensive judgment mechanism avoids misjudgments that may be caused by judging a single indicator, and significantly improves the accuracy of fault diagnosis. Accurate identification of the gas proportional valve's fading allows the heating and hot water boiler to take timely and targeted compensatory measures, such as adjusting the control strategy of the gas proportional valve or prompting the user for maintenance, thereby effectively extending the equipment's service life, ensuring the long-term stable operation and combustion efficiency of the heating and hot water boiler, reducing operating costs, and improving the user experience.

[0083] While the embodiments described above in this application propose identifying combustion feature combination modes based on multiple combustion characteristics and specifically provide a method for identifying the self-fading mode of the gas proportional valve, the performance degradation of heating and hot water boilers is not limited to problems with the gas proportional valve itself. In actual operation, the performance degradation of key components such as fans or burners can also significantly affect combustion efficiency and heat output. If only the degradation of the gas proportional valve is considered while ignoring potential problems with other components, it may lead to a misjudgment of the overall system performance decline, resulting in inappropriate compensation measures that fail to fundamentally solve the problem and may even accelerate the damage to other components.

[0084] In response, this application further proposes to identify combustion feature combination modes, which also includes: if the linear regression slope of the opening command deviation is greater than a first preset threshold; at the same time, the ratio of the peak value to the average value of the power spectral density in the flame ion current feature deviation in a preset low frequency band is less than or equal to a second preset threshold, and the average value of the exhaust temperature deviation is greater than a fourth preset threshold; then the combustion feature combination mode is determined to be a fan or burner decay mode.

[0085] Specifically, if the linear regression slope of the aforementioned opening command deviation is greater than the first preset threshold, it means that in order to maintain the same heat output demand, the opening command of the gas proportional valve continues to increase. This usually indicates a decrease in the overall combustion efficiency of the system, requiring more gas supply. The ratio of the peak value to the average value of the power spectral density in the preset low-frequency band of the flame ion current characteristic deviation is less than or equal to the second preset threshold. This can be understood as relatively good flame stability, without the severe fluctuations or unstable combustion characteristics commonly seen when the gas proportional valve itself declines. In practical applications, if the average value of the exhaust gas temperature deviation is greater than the fourth preset threshold, it means that the exhaust gas temperature is significantly higher than the reference value. This is usually due to incomplete combustion, reduced heat exchange efficiency, or insufficient fan air supply, resulting in heat not being effectively transferred to the water side and instead being discharged with the flue gas.

[0086] This application's solution effectively distinguishes different types of performance degradation by comprehensively analyzing three key indicators: opening command deviation, flame ion current characteristic deviation, and flue gas temperature deviation. When the linear regression slope of the opening command deviation continuously increases, it indicates that the system requires more gas to maintain heat output, which is similar to the initial signs of gas proportional valve degradation. However, if the stability of the flame ion current (measured by the ratio of the peak value to the average value of the power spectral density in the preset low-frequency band) remains within the normal range or fluctuates insignificantly, and the flue gas temperature increases significantly, the possibility of combustion instability caused by deviation of the gas proportional valve's own flow characteristics is ruled out. Conversely, this combined mode tends to indicate a decline in fan performance (such as insufficient speed, reduced airflow leading to insufficient oxygen supply) or burner blockage and carbon buildup (leading to incomplete combustion, abnormal flame morphology, and reduced heat exchange efficiency), resulting in a large amount of heat being discharged with the high-temperature flue gas. Through this multi-dimensional and complementary feature analysis, this application can avoid the limitations of single-indicator judgment and achieve accurate identification of fan or burner degradation modes.

[0087] Through the above technical solution, this application further expands the fault diagnosis capabilities of the adaptive control system for heating and hot water boilers. Compared to only identifying the self-fading mode of the gas proportional valve, this application can identify the fading mode of the fan or burner, thus providing a more comprehensive and accurate basis for the maintenance and troubleshooting of the heating and hot water boiler. This distinguishing ability allows the system to adopt customized compensation or alarm strategies for different causes of fading. For example, when fan or burner fading is identified, the system can prompt the user to clean or repair it, rather than simply adjusting the opening command of the gas proportional valve. This not only improves the accuracy of fault diagnosis but also extends the service life of the heating and hot water boiler, reduces operating energy consumption, and enhances the user experience.

[0088] In some preferred embodiments, a specific example is given below. Suppose that after a period of operation, a fully premixed gas-fired heating and hot water boiler experiences user feedback of decreased heating efficiency, but the opening command of the gas proportional valve continues to increase in an attempt to maintain the set temperature. At this time, the system monitors in real time that the linear regression slope of the opening command deviation is consistently greater than a first preset threshold (e.g., 0.05% / day), indicating an increase in gas demand. Simultaneously, the ratio of the peak to average value of the power spectral density in the flame ion current characteristic deviation within a preset low-frequency band is detected to be less than or equal to a second preset threshold (e.g., 1.5), indicating that the flame combustion state is relatively stable and there is no severe fluctuation commonly seen when the gas proportional valve itself declines. However, the average value of the flue gas temperature deviation is detected to be greater than a fourth preset threshold (e.g., +10°C), indicating a significant increase in flue gas temperature. Based on the above combined characteristics, the system accurately determines that the current combustion characteristic combination mode is a fan or burner decline mode. For example, this may be due to insufficient airflow caused by ash accumulation on the fan blades, or partial blockage of the burner nozzles leading to uneven mixing of gas and air, resulting in incomplete combustion and decreased heat exchange efficiency. The system can then issue prompts to users to "clean or inspect the fan / burner" instead of incorrectly attempting to compensate for the performance of the gas proportional valve, thereby achieving accurate fault location and maintenance recommendations.

[0089] In some embodiments described above, a method for recording combustion characteristic benchmarks under the initial operating conditions of a heating hot water boiler is proposed. However, if the purity of the combustion state is not rigorously assessed during implementation, the recorded benchmark data may be biased, thereby affecting the accuracy of subsequent performance degradation identification and compensation. To address this, this application further proposes specific steps for recording and storing the fan speed, benchmark opening command, flame ion current stability characteristics, flue gas temperature, and actual heat output under preset heat output requirements during the initial operating conditions of the heating hot water boiler as combustion characteristic benchmarks. This aims to ensure the accuracy and reliability of the recorded benchmark data.

[0090] Specifically, in the initial operating state of the heating hot water boiler, under the preset heat output demand, the fan speed, reference opening command, flame ion current stability characteristics, flue gas temperature, and actual heat output are recorded and stored as combustion characteristic references, including:

[0091] In the initial operating state of the heating hot water boiler, it operates at a preset heat output demand point. After the heating hot water boiler reaches and maintains a stable state at the preset heat output demand point, the continuous data acquisition window is activated to acquire flame ion current signals and flue gas temperature data.

[0092] The flame ion current signal is subjected to frequency domain analysis to calculate its power spectral density, and the energy distribution in the predetermined low frequency band is evaluated to determine whether there is abnormal concentration or significant peak, and the power spectral density analysis results are obtained.

[0093] The instantaneous fluctuation amplitude of the exhaust temperature data is calculated, and based on the power spectral density analysis results and the instantaneous fluctuation amplitude, it is determined whether the current combustion state is pure.

[0094] In response to the current pure combustion state, the current gas proportional valve opening command, flame ion current signal, and exhaust temperature data are recorded as the reference opening command, flame ion current stability characteristics, and exhaust temperature for the heat output point, and stored as combustion characteristic references.

[0095] In this embodiment, "steady state" refers to the state where, under a preset heat output demand, the operating parameters of the heating water boiler (such as fan speed, gas proportional valve opening, flame ionization current, and flue gas temperature) fluctuate within an acceptable range after a period of adjustment, indicating that the combustion process has reached equilibrium and stability. Reaching and maintaining a stable state at this heat output point ensures that subsequent data acquisition accurately reflects the ideal combustion characteristics under this heat output demand, avoiding measurement errors caused by system instability. "Continuous data acquisition window" refers to opening a preset data acquisition period after the system reaches a stable state, continuously and uninterruptedly acquiring flame ionization current signals and flue gas temperature data during this period to accumulate sufficient data for subsequent analysis. "Frequency domain analysis" refers to converting the acquired flame ionization current signal from the time domain to the frequency domain for analysis, for example, using methods such as Fast Fourier Transform (FFT). Frequency domain analysis can reveal potential periodic fluctuations or instabilities in the flame combustion process. "Power spectral density" is one of the results of frequency domain analysis; it describes the distribution of the signal's energy or power at different frequencies. During combustion, the stability of the flame is closely related to the frequency characteristics of the flame ion current signal. If the flame combustion is unstable, such as with pulsating combustion or incomplete combustion, the flame ion current signal may exhibit abnormally concentrated energy distribution or significant peaks in a specific low-frequency band. These phenomena are important indicators of the purity of the combustion state. "Instantaneous fluctuation amplitude" refers to the range or dispersion of flue gas temperature data over a short period. A stable combustion state typically corresponds to a small flue gas temperature fluctuation amplitude, while unstable or abnormal combustion may result in increased fluctuations. By comprehensively analyzing the power spectral density analysis results of the flame ion current signal and the instantaneous fluctuation amplitude of the flue gas temperature data, a comprehensive and accurate assessment of the purity of the current combustion state can be made. When the combustion state is determined to be pure, the system is considered to be operating under ideal and stable combustion conditions, and only then do the recorded parameters have representativeness and reliability as a "combustion characteristic benchmark."

[0096] This application's solution introduces a rigorous mechanism for judging the purity of the combustion state before recording combustion characteristic benchmarks. First, it ensures that the heating water boiler reaches and maintains a stable operating state under preset heat output requirements, providing a reliable prerequisite for benchmark data acquisition. Second, by performing frequency domain analysis on the flame ion current signal, particularly focusing on the power spectral density in a predetermined low-frequency band, it can effectively identify combustion instability phenomena that are difficult to detect with the naked eye, such as flame pulsation or incomplete combustion. Simultaneously, combining the instantaneous fluctuation amplitude of the exhaust gas temperature data further verifies the stability and efficiency of combustion. Only when these indicators all indicate that the current combustion state is pure are the corresponding operating parameters recorded as combustion characteristic benchmarks. This multi-dimensional and refined judgment mechanism avoids recording benchmark data under unstable or abnormal combustion states, thus ensuring the accuracy of the benchmark data from the source.

[0097] The above technical solution significantly improves the accuracy and reliability of the recorded combustion characteristic benchmarks. Since the benchmark data is acquired under pure and stable combustion conditions, subsequent calculations of opening command deviations, flame ionization current characteristic deviations, and flue gas temperature deviations based on this benchmark data will be more accurate. This leads to more accurate identification of deviations in the gas proportional valve flow characteristics and combustion characteristic combination modes. This effectively avoids misjudgments or omissions caused by inaccurate benchmark data, thereby improving the overall performance and robustness of the adaptive control method for fully premixed gas-fired heating and hot water boilers. It ensures that the heating and hot water boiler can more accurately identify and compensate for performance degradation during long-term operation, maintaining efficient and stable combustion.

[0098] In some preferred embodiments, it is assumed that the combustion characteristic baseline of the heating water boiler needs to be established after initial installation or major overhaul. First, the heating water boiler is set to a medium heat output demand point, such as 50% of rated heat output. After system startup, the controller continuously monitors parameters such as fan speed, gas proportional valve opening, flame ionization current, and flue gas temperature until the fluctuation range of these parameters is less than a preset threshold for 5 consecutive minutes, indicating that the system has reached a stable state. Subsequently, a 30-second continuous data acquisition window is initiated to acquire flame ionization current signals and flue gas temperature data at high speed. A fast Fourier transform is performed on the acquired flame ionization current signal to calculate its power spectral density, with a focus on analyzing the energy distribution in the 0-10Hz low-frequency band. If no significant energy concentration or peak occurs in this low-frequency band (e.g., the ratio of peak value to average value is less than a preset threshold), the flame combustion is considered stable. Simultaneously, the standard deviation of the flue gas temperature data within 30 seconds is calculated. If the standard deviation is less than a preset threshold, the flue gas temperature fluctuation is considered small, indicating stable combustion. When both conditions are met, the current combustion state is determined to be pure. At this point, the system will record the current fan speed, gas proportional valve opening command, average value and power spectral density characteristics of the flame ionization current signal, average value of the flue gas temperature, and actual heat output, and store these as the combustion characteristic benchmark for this 50% heat output demand point. If any condition is not met, the system will indicate that the combustion state is not pure, and it may be necessary to readjust the operating parameters or troubleshoot until a pure state is achieved before recording the benchmark, thus ensuring the quality of the benchmark data.

[0099] Furthermore, specific embodiments of this application also disclose an adaptive control system for a fully premixed gas-fired heating and hot water boiler, wherein the heating and hot water boiler includes a gas proportional valve and a fan, such as... Figure 2 As shown, the system includes:

[0100] Monitoring module 201 is used to monitor the current opening command of the gas proportional valve in real time, and determine the opening command deviation based on the current opening command and preset benchmark operating parameters;

[0101] Analysis module 202 is used to analyze the changing trend of the opening command deviation in order to determine the deviation of the flow characteristics of the gas proportional valve;

[0102] Compensation module 203 is used to determine a performance compensation factor based on the deviation of the flow characteristics; the performance compensation factor is used to indicate the rate and extent of performance degradation of the gas proportional valve;

[0103] The control module 204 is used to modify the current opening command according to the performance compensation factor in order to adjust and control the gas supply.

[0104] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An adaptive control method for a fully premixed gas-fired heating and hot water boiler, wherein the heating and hot water boiler includes a gas proportional valve and a fan, characterized in that, The method includes: The current opening command of the gas proportional valve is monitored in real time, and the opening command deviation is determined based on the current opening command and preset benchmark operating parameters. Analyze the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve; A performance compensation factor is determined based on the deviation of the flow characteristics; the performance compensation factor is used to indicate the rate and extent of performance degradation of the gas proportional valve. Based on the performance compensation factor, the current opening command is corrected to regulate and control the gas supply; Before real-time monitoring of the current opening command of the gas proportional valve, the method further includes: in the initial operating state of the heating hot water boiler, under the preset heat output demand, recording the fan speed, reference opening command, flame ion current stability characteristics, flue gas temperature and actual heat output, and storing them as combustion characteristic references; The analysis of the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve includes: Real-time monitoring of the current opening command, flame ion current stability characteristics, and exhaust temperature under the current heat output demand, and comparison with the corresponding benchmark values ​​under the same heat output demand in the combustion characteristic benchmark, and calculation of opening command deviation, flame ion current characteristic deviation, and exhaust temperature deviation; Based on long-term recorded deviations in opening commands, flame ion current characteristics, and exhaust temperature, combustion characteristic combination modes are identified; these combustion characteristic combination modes include gas proportional valve self-fading mode and fan or burner fading mode.

2. The adaptive control method for a fully premixed gas-fired heating and hot water boiler according to claim 1, characterized in that, Before real-time monitoring of the current opening command of the gas proportional valve, the method further includes: in the initial operating state of the heating hot water boiler, under the preset heat output demand, recording the correspondence between the fan speed and the reference opening command of the gas proportional valve, and storing it as a reference operating parameter. The step of determining the opening command deviation based on the current opening command and the preset benchmark operating parameters includes: comparing the current opening command with the benchmark opening command corresponding to the same heat output demand in the benchmark operating parameters, and calculating the opening command deviation.

3. The adaptive control method for a fully premixed gas-fired heating and hot water boiler according to claim 2, characterized in that, The analysis of the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve includes: Collect opening command deviation data and store it in the current sliding time window, and remove outliers; Calculate the weighted average of the opening command deviation data after removing outliers to obtain the weighted average command deviation of the current sliding time window; By comparing the weighted average command deviation of the current sliding time window with the weighted average command deviation of the previous time window, and determining that the weighted average command deviation has an increasing trend, it is determined that the flow characteristics of the gas proportional valve have deviated.

4. The adaptive control method for a fully premixed gas-fired heating and hot water boiler according to claim 3, characterized in that, A performance compensation factor is determined based on the deviation of the flow characteristics, including: A linear regression algorithm is used to fit the average command deviation data within a historical preset time period to obtain the slope of the opening command deviation changing over time; the product of the slope and a sensitivity coefficient is used as the performance compensation factor.

5. The adaptive control method for a fully premixed gas-fired heating and hot water boiler according to claim 1, characterized in that, A performance compensation factor is determined based on the deviation of the flow characteristics, including: In response to the combustion characteristic combination mode being the gas proportional valve self-fading mode, a linear regression algorithm is used to fit the average command deviation data within a historical preset time period to obtain the slope of the opening command deviation changing over time; the product of the slope and a sensitivity coefficient is used as the performance compensation factor.

6. The adaptive control method for a fully premixed gas-fired heating and hot water boiler according to claim 1, characterized in that, The identified combustion feature combination pattern includes: If the linear regression slope of the opening command deviation is greater than the first preset threshold; and simultaneously, the ratio of the peak value to the average value of the power spectral density in the flame ion current characteristic deviation within the preset low frequency band is greater than the second preset threshold, and the average value of the exhaust temperature deviation is less than zero, and its absolute value is greater than the third preset threshold; then the combustion characteristic combination mode is determined to be the gas proportional valve self-fading mode.

7. The adaptive control method for a fully premixed gas-fired heating and hot water boiler according to claim 6, characterized in that, The identification of combustion feature combination patterns also includes: If the linear regression slope of the opening command deviation is greater than the first preset threshold; and simultaneously, the ratio of the peak value to the average value of the power spectral density in the flame ion current characteristic deviation within the preset low frequency band is less than or equal to the second preset threshold, and the average value of the exhaust temperature deviation is greater than the fourth preset threshold; then the combustion characteristic combination mode is determined to be the fan or burner decay mode.

8. The adaptive control method for a fully premixed gas-fired heating and hot water boiler according to any one of claims 6-7, characterized in that, In the initial operating state of the heating hot water boiler, under the preset heat output demand, the fan speed, reference opening command, flame ion current stability characteristics, flue gas temperature, and actual heat output are recorded and stored as combustion characteristic references, including: In the initial operating state of the heating hot water boiler, it operates at a preset heat output demand point. After the heating hot water boiler reaches and maintains a stable state at the preset heat output demand point, the continuous data acquisition window is activated to acquire flame ion current signals and flue gas temperature data. The flame ion current signal is subjected to frequency domain analysis to calculate its power spectral density, and the energy distribution in the predetermined low frequency band is evaluated to determine whether there is abnormal concentration or significant peak, and the power spectral density analysis results are obtained. The instantaneous fluctuation amplitude of the exhaust temperature data is calculated, and based on the power spectral density analysis results and the instantaneous fluctuation amplitude, it is determined whether the current combustion state is pure. In response to the current pure combustion state, the current gas proportional valve opening command, flame ion current signal, and exhaust temperature data are recorded as the reference opening command, flame ion current stability characteristics, and exhaust temperature for the heat output point, and stored as combustion characteristic references.

9. An adaptive control system for a fully premixed gas-fired heating and hot water boiler, the boiler comprising a gas proportional valve and a fan, characterized in that, The system includes: The monitoring module is used to monitor the current opening command of the gas proportional valve in real time, and determine the opening command deviation based on the current opening command and preset benchmark operating parameters. The analysis module is used to analyze the changing trend of the opening command deviation in order to determine the deviation of the flow characteristics of the gas proportional valve; The compensation module is used to determine a performance compensation factor based on the deviation of the flow characteristics; the performance compensation factor is used to indicate the rate and extent of performance degradation of the gas proportional valve; The control module is used to correct the current opening command according to the performance compensation factor in order to adjust and control the gas supply; Before real-time monitoring of the current opening command of the gas proportional valve, it also includes: in the initial operating state of the heating hot water boiler, under the preset heat output demand, recording the fan speed, reference opening command, flame ion current stability characteristics, flue gas temperature and actual heat output, and storing them as combustion characteristic references; The analysis of the changing trend of the opening command deviation to determine the deviation of the flow characteristics of the gas proportional valve includes: Real-time monitoring of the current opening command, flame ion current stability characteristics, and exhaust temperature under the current heat output demand, and comparison with the corresponding benchmark values ​​under the same heat output demand in the combustion characteristic benchmark, and calculation of opening command deviation, flame ion current characteristic deviation, and exhaust temperature deviation; Based on long-term recorded deviations in opening commands, flame ion current characteristics, and exhaust temperature, combustion characteristic combination modes are identified; these combustion characteristic combination modes include gas proportional valve self-fading mode and fan or burner fading mode.

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