Gas-fired heating water heater flameout control method, system, device and medium

Abstract

This application relates to a flameout control method, system, equipment, and medium for a gas-fired heating and hot water boiler. The gas-fired heating and hot water boiler includes a sealed combustion system, a Venturi mixer, and a pneumatic gas valve connected in sequence. The pilot valve of the pneumatic gas valve is connected to the air purification chamber of the sealed combustion system via an air pressure pipe. The method includes: during the overall commissioning phase, setting the zero-position adjusting spring pressure of the pilot valve of the pneumatic gas valve to a negative value; during the boiler operation phase, determining whether the combustion flame has detached and extinguished based on the ratio of gas flow rate to air flow rate; and in response to flame detachment and extinguishment, closing the pneumatic gas valve via a controller. This application can shut down the pneumatic gas valve and extinguish the entire boiler when the flue is severely blocked, thereby protecting the gas-fired heating and hot water boiler.

Description

Technical Field

[0001] This application relates to the field of gas-fired hot water boiler technology, and in particular to a method, system, equipment and storage medium for controlling the flameout of a gas-fired heating hot water boiler. Background Technology

[0002] The working principle of a fully premixed gas heating and hot water boiler is to adjust the speed of a DC fan by adjusting the duty cycle (i.e., PWM value) of a rectangular wave with a certain frequency according to the heating load demand of the wall-hung boiler, thereby controlling the air volume of the fan. A Venturi mixer is used to ensure that the gas and air are fully mixed at the fan inlet, and to achieve synchronous adjustment of the gas flow and air flow, while maintaining a constant ratio.

[0003] For existing fully premixed wall-hung boilers, air enters the cavity between the top and bottom covers of the boiler through the flue pipe. When the boiler is working and the fan is running, as the flue pipe becomes more clogged, the negative pressure between the top and bottom covers increases. Indoor air will be drawn into the combustion system through the gap between the top and bottom covers, causing the flame to fail to extinguish when the flue pipe is clogged, which poses a serious safety hazard. Summary of the Invention

[0004] In view of the above, this application provides a flameout control method, system, equipment and storage medium for gas-fired heating and hot water boilers, the purpose of which is to solve the above-mentioned technical problems.

[0005] In a first aspect, this application provides a flameout control method for a gas-fired heating and hot water boiler. The gas-fired heating and hot water boiler includes a sealed combustion system, a Venturi mixer, a fan, and a pneumatic gas valve connected in sequence. The control valve of the pneumatic gas valve is connected to the air purification chamber of the sealed combustion system via an air pressure pipe. The method includes:

[0006] During the overall machine debugging phase, the zero-position adjusting spring pressure Os of the pneumatic gas valve's control valve is set to a negative value.

[0007] During the operation of the hot water boiler, the combustion flame is determined to be extinguished based on the ratio of gas flow rate to air flow rate; wherein, when the zero-position adjusting spring pressure Os is negative and the combustion system is sealed, the degree of flame extinguishing is negatively correlated with the magnitude of the ratio of gas flow rate to air flow rate.

[0008] In response to the flame extinguishing upon flame lift-off, the pneumatic gas valve is closed via the controller.

[0009] In some embodiments, the ratio of the gas flow rate to the air flow rate is determined in the following manner:

[0010] The oxygen concentration after flame combustion is monitored by a sensor installed in the flue of the gas-fired heating and hot water boiler.

[0011] Based on a preset mapping table and the oxygen concentration, the ratio of the gas flow rate to the air flow rate is determined.

[0012] In some embodiments, determining whether the combustion flame has extinguished due to flame lift-off based on the ratio of the gas flow rate to the air flow rate includes:

[0013] Determine whether the ratio of the gas flow rate to the air flow rate meets a preset condition;

[0014] If so, confirm that the combustion flame has extinguished upon removal from the flame.

[0015] In some embodiments, determining whether the combustion flame has extinguished due to flame lift-off based on the ratio of the gas flow rate to the air flow rate includes:

[0016] Determine whether the ratio of the gas flow rate to the air flow rate meets a preset condition;

[0017] If so, detect the intensity of the flame signal of the combustion flame;

[0018] When the flame signal intensity is less than a preset flame intensity threshold, the combustion flame is determined to extinguish.

[0019] In some embodiments, detecting the flame signal intensity of the combustion flame includes:

[0020] The controller acquires flame current signals at a preset sampling frequency.

[0021] The collected flame current signal is filtered by moving average to obtain the flame signal intensity of the combustion flame.

[0022] In some embodiments, before determining whether the ratio of the gas flow rate to the air flow rate meets a preset condition, the method includes:

[0023] Obtain the fan speed of the hot water boiler;

[0024] As the ratio of gas flow rate to air flow rate gradually decreases, the fan speed is increased until it reaches the maximum speed.

[0025] In some embodiments, the preset conditions include the ratio of gas flow rate to air flow rate continuously decreasing within a preset time period or the ratio of gas flow rate to air flow rate being lower than a preset threshold.

[0026] Secondly, this application provides a flameout control system for a gas-fired heating and hot water boiler. The gas-fired heating and hot water boiler includes a sealed combustion system, a Venturi mixer, a fan, and a pneumatic gas valve connected in sequence. The control valve of the pneumatic gas valve is connected to the air purification chamber of the sealed combustion system via an air pressure pipe. The system includes:

[0027] The debugging module is used to set the zero-position adjusting spring pressure Os of the pneumatic gas valve's control valve to a negative value during the overall machine debugging phase.

[0028] The determination module is used to determine whether the combustion flame has detached and extinguished based on the ratio of gas flow rate to air flow rate during the operation of the hot water boiler; wherein, when the zero-position adjusting spring pressure Os is negative and the combustion system is sealed, the degree of flame detachment is negatively correlated with the magnitude of the ratio of gas flow rate to air flow rate.

[0029] The control module is used to close the pneumatic gas valve via a controller in response to the flame extinguishing.

[0030] Thirdly, this application provides an electronic device, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus;

[0031] Memory, used to store computer programs;

[0032] When a processor executes a program stored in a memory, it implements the steps of the flameout control method for a gas-fired heating hot water boiler as described in any embodiment of the first aspect.

[0033] Fourthly, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps of the gas-fired heating hot water boiler flameout control method as described in any embodiment of the first aspect.

[0034] The technical solutions provided in this application have the following advantages compared with the prior art:

[0035] During the overall commissioning process, Os (the spring pressure for zero-position adjustment) is set to a negative number. During the operation of the gas-fired heating and hot water boiler, as the flue pipe becomes blocked, the speed of the DC fan increases. When the DC fan reaches its maximum speed, the flue pipe continues to become blocked, causing the airflow Qa to gradually decrease (correspondingly, Pa-PT continuously decreases), and the combustion load decreases accordingly. As Pa-PT continues to decrease, Qg / Qa continuously decreases, increasing the air-fuel ratio. Based on the principles of combustion, a deviation of the air-fuel ratio (i.e., the ratio of airflow to gasflow) from the ideal value leads to changes in flame velocity, causing the flame to rise and resulting in flame lift-off. As the flame rises, it gradually moves away from the optimal detection distance of the flame detector, causing the flame detector to fail to detect the flame. The controller then closes the pneumatic gas valve, and the entire unit shuts off, providing flue pipe blockage protection. Throughout this process, the controller does not need to obtain the actual values ​​of Ka, Pa, PT, Kg, and Pg; it only needs to set Os to a negative number and ensure the combustion system is in a sealed state (i.e., air will not be drawn into the combustion system through the gaps in the top and bottom covers) to achieve automatic flameout protection during flue pipe blockage. Attached Figure Description

[0036] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0037] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a flowchart illustrating a preferred embodiment of the flameout control method for a gas-fired heating hot water boiler according to this application.

[0039] Figure 2 This is a schematic diagram of a preferred embodiment of the flameout control system for a gas-fired heating and hot water boiler in this application;

[0040] Figure 3 An exemplary structural diagram of a combustion system for a gas-fired heating hot water boiler provided in this application embodiment;

[0041] Figure 4 This is an exemplary structural diagram of a gas-fired heating and hot water boiler provided in an embodiment of this application;

[0042] Figure 5 This is a schematic diagram of a preferred embodiment of the electronic device of this application;

[0043] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0045] It should be noted that the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

[0046] Reference Figure 1 The diagram shown is a flowchart illustrating an embodiment of the gas-fired heating hot water boiler flameout control method of this application. The method is executed by an electronic device, which can be implemented by a software system and / or a hardware system. The gas-fired heating hot water boiler flameout control method includes:

[0047] Step 101: During the overall machine debugging stage, set the zero-position adjusting spring pressure Os of the pneumatic gas valve's control valve to a negative value.

[0048] The gas-fired heating and hot water boiler described in this application is a fully premixed gas-fired heating and hot water boiler. The overall commissioning stage is the system debugging and calibration stage performed after the gas-fired heating and hot water boiler leaves the factory or is installed. The purpose is to ensure that the parameters of each component are set correctly and that the functions are normal. For example, it is the process by which technicians use special tools to perform initial calibration of the combustion system, valves, and sensors before the hot water boiler is started for the first time.

[0049] A pneumatic gas valve is a gas valve controlled by a gas pressure signal. It is used to regulate or cut off the gas supply, and its opening degree depends on the input gas pressure signal.

[0050] The pilot valve is a control component in a pneumatic gas valve, used to receive external pressure signals and amplify those signals to control the operation of the main valve.

[0051] The zero-position adjusting spring pressure Os is the preset pressure value of the internal spring of the control valve when it is in the zero position (no external pressure signal). It is used to calibrate the reference position of the valve and ensure that the valve is in a specific state when there is no signal.

[0052] Step 102: During the operation of the hot water boiler, determine whether the combustion flame has extinguished due to flame lift-off based on the ratio of gas flow rate to air flow rate.

[0053] The hot water boiler operation phase is the period during which the gas-fired heating hot water boiler works normally, including heating mode or hot water supply mode, during which the combustion system runs continuously.

[0054] An air pressure pipe is a conduit connecting the air purification chamber and the control valve, used to transmit pressure signals from the air purification chamber to the control valve. For example, a flexible plastic or metal tube can carry pressure from the combustion system to a pneumatic gas valve.

[0055] An air purification chamber is a compartment in a sealed combustion system used to filter or stabilize airflow, ensuring the purity and pressure stability of the combustion air.

[0056] When the zero-position adjusting spring pressure Os is negative and the combustion system is sealed, the degree of flame lift-off is negatively correlated with the ratio of gas flow rate to air flow rate. This negative correlation means that as the ratio of gas flow rate to air flow rate decreases, the degree of flame lift-off increases. When the flame lift-off reaches a certain height (e.g., 5cm or 10cm), it may cause the flame to extinguish.

[0057] The ratio of gas flow rate to air flow rate is related to the air pressure Pa in the air purification chamber, the zero-position adjustment spring pressure Os, the air flow rate Qa of the venturi mixer, and the gas flow rate Qg of the pneumatic gas valve.

[0058] Air pressure Pa is the gas pressure inside the air purification chamber, indicating the pressure level inside the chamber relative to atmospheric pressure. Positive pressure means the pressure is higher than atmospheric pressure, and negative pressure means the pressure is lower than atmospheric pressure.

[0059] Gas flow rate Qg is the volumetric flow rate of gas through a pneumatic gas valve, representing the amount of gas flowing through the valve per unit time. Commonly used units include cubic meters per hour.

[0060] Flame detachment is the phenomenon where the combustion flame detaches from the burner orifice and extinguishes itself. It can be caused by an imbalance in the air-fuel mixture ratio or by airflow disturbances leading to flame instability.

[0061] In some embodiments, the ratio of gas flow rate to air flow rate is related to the air pressure Pa, the zero-position adjusting spring pressure Os, and the gas flow rate Qg of the pneumatic gas valve.

[0062] The following describes the relationship between the ratio of gas flow rate to air flow rate and the air pressure Pa, the zero-position adjusting spring pressure Os, and the gas flow rate Qg of the pneumatic gas valve when the zero-position adjusting spring pressure Os is negative and the combustion system is sealed.

[0063] S10, the diaphragm of the control valve bears the sum of the air pressure Pa and the zero-position adjusting spring pressure Os on one side, and the gas pressure Pg on the other side. Under mechanical equilibrium, Pg = Os + Pa is satisfied.

[0064] A diaphragm is a flexible diaphragm assembly in a control valve. It can be made of rubber or metal and is used to separate different pressure chambers and convert pressure into mechanical displacement. For example, a circular diaphragm may have one side in contact with air pressure and the other side in contact with fuel gas pressure.

[0065] Mechanical equilibrium is the static state reached by the diaphragm of the control valve under the action of pressure on both sides. At this time, the diaphragm has no net displacement, and the pressure difference on both sides is balanced with the spring force.

[0066] S11, the airflow rate Qa through the Venturi mixer satisfies Qa = Ka × (Pa - Pt). 1 / 2 Where Ka is the air resistance coefficient of the Venturi mixer, and Pt is the throat pressure of the Venturi mixer.

[0067] A Venturi mixer is a tubular device in a gas-fired heating and hot water boiler used to mix air and gas. It promotes mixing by creating pressure changes through a contraction-expansion structure. For example, in a tapered pipe, air velocity increases and pressure decreases as it flows in.

[0068] Airflow rate Qa is the volume of air flowing through the Venturi mixer per unit time, representing the air supply rate.

[0069] The air resistance coefficient Ka of a Venturi mixer is a constant characterizing the airflow resistance of the Venturi mixer. The value of Ka depends on the geometry and surface characteristics of the mixer.

[0070] Throat pressure Pt is the gas pressure at the narrowest point (throat) of the Venturi mixer.

[0071] S12, the gas flow rate Qg passing through the pneumatic gas valve satisfies: Qg = Kg × (Pg - Pt) 1 / 2 , where Kg is the gas resistance coefficient.

[0072] The gas resistance coefficient Kg is a constant characterizing the resistance of a pneumatic gas valve to gas flow.

[0073] S13, determine that the ratio of gas flow rate to air flow rate satisfies: Qg / Qa=(Kg / Ka)×[1+Os / (Pa-Pt)] 1 / 2 .

[0074] The ratio of gas flow rate to air flow rate is expressed as the ratio of gas flow rate Qg to air flow rate Qa. It is used to describe the mixing ratio of gas and air, which affects the stability of the combustion flame.

[0075] S14, Based on the ratio of the gas flow rate to the air flow rate, determine whether the combustion flame has extinguished due to flame lift-off.

[0076] In some embodiments, if the ratio of gas flow rate to air flow rate (e.g., Qg / Qa) exceeds a threshold range (e.g., below a minimum threshold or above a maximum threshold), the combustion flame is determined to be at risk of flameout; otherwise, the flame is stable. Based on the principles of combustion, a deviation of the air-fuel ratio (i.e., the ratio of air flow rate to gas flow rate) from the ideal value will cause a change in flame velocity, thereby triggering flameout.

[0077] According to Bernoulli's equation, the airflow through the Venturi mixer is given by equation (1):

[0078] Qa = Ka × (Pa - PT) 1 / 2 (1)

[0079] Where Qa is the airflow rate; Ka is the air resistance coefficient of the Venturi mixer, which is a constant; Pa is the pressure before the Venturi mixer; and PT is the throat pressure of the Venturi mixer.

[0080] According to Bernoulli's equation, the gas flow rate through the Venturi mixer is given by equation (2):

[0081] Qg = Kg × (Pg - PT) 1 / 2 (2)

[0082] Where Qg is the gas flow rate; Kg is the gas resistance coefficient, which is a constant; Pg is the pressure in front of the valve plate of the pneumatic gas valve; and PT is the throat pressure of the Venturi mixer.

[0083] According to the working principle of the pneumatic gas valve, the diaphragm of the pneumatic gas valve is subjected to the following forces on both sides: one side is subjected to the spring pressure (Os) of zero-position adjustment and is connected to the air pressure Pa through the air pressure pipe, and the other side is subjected to the gas pressure Pg.

[0084] Therefore, we have equation (3):

[0085] Pg = Os + Pa (3)

[0086] Where Os is the spring pressure for zero-position adjustment, and Os is set to a negative number during the whole machine debugging process;

[0087] Equation (4) is obtained from equations (1) and (2):

[0088] Qg / Qa = Kg × (Pg - PT) 1 / 2 / [Ka×(Pa-PT) 1 / 2 = Kg / Ka × [(Pg-PT) / (Pa-PT)] 1 / 2 (4)

[0089] Substituting equation (3) into equation (4) yields equation (5):

[0090] Qg / Qa = Kg / Ka × [1 + Os / (Pa - PT)] 1 / 2 (5)

[0091] The flameout protection process of the combustion system provided in this application embodiment is as follows:

[0092] 1. During the whole machine debugging process, set Os (spring pressure for zero-position adjustment) to a negative number; (setting it to a negative number is a prerequisite for Qg / Qa to decrease when the blockage is severe).

[0093] 2. During the operation of the gas-fired heating and hot water boiler, if the flue pipe becomes blocked, the controller increases the speed of the DC fan by adjusting the duty cycle (i.e., the PWM value) to maintain a constant air volume and thus maintain the actual required combustion heat load.

[0094] 3. When the DC fan reaches its maximum speed, the flue pipe continues to be blocked, and the fan speed cannot be increased. At this time, the air flow rate Qa will gradually decrease, thereby reducing the combustion load. As Qa decreases, Pa-PT can be derived from equation (1) to gradually decrease.

[0095] 4. As the blockage worsens, Pa-PT gradually decreases. According to equation (5), Qg / Qa gradually decreases (derivation process: Pa-PT gradually decreases, 1 / (Pa-PT) gradually increases, because Os is negative, Os / (Pa-PT) gradually decreases, 1+Os / (Pa-PT) gradually decreases, Qg / Qa=Kg / Ka×[1+Os / (Pa-PT)] 1 / 2 (Gradually decreasing), that is, the air-fuel ratio increases, and the combustion flame rises, resulting in flame lift-off.

[0096] 5. Because the combustion system is sealed (i.e., air cannot be drawn into the combustion system through the gaps between the top and bottom covers), when the fan reaches its maximum speed, as the blockage worsens, the combustion flame exhibits flame lift-off. The feedback needle cannot detect the flame, and the controller will close the pneumatic gas valve to achieve flameout protection. Throughout this process, the controller does not need to obtain the actual values ​​of Ka, Pa, PT, Kg, and Pg; it only needs to set Os to a negative number and ensure the combustion system is sealed to achieve automatic flameout protection when the flue is blocked. It should be noted that the above formula derivation only explains the principle of automatic flameout protection when Os is negative and the combustion system is sealed. In practical applications, the controller does not need to obtain the actual values ​​of Ka, Pa, PT, Kg, and Pg for calculations.

[0097] Without needing to obtain the actual values ​​of Ka, Pa, PT, Kg, and Pg, the ratio of gas flow rate to air flow rate can be determined as follows: by monitoring the oxygen concentration after flame combustion using a sensor installed in the flue of the gas-fired heating and hot water boiler; and by determining the ratio of gas flow rate to air flow rate based on a preset mapping table and the oxygen concentration.

[0098] Sensors can be of various types that monitor oxygen concentration. For example, electrochemical sensors.

[0099] A pre-defined mapping table is a pre-established table reflecting the correspondence between oxygen concentration and the ratio of gas flow rate to air flow rate. In this table, different oxygen concentrations have a one-to-one correspondence with the gas flow rate to air flow rate ratio. It is understandable that, according to the law of conservation of mass, matter cannot be created or destroyed during combustion. All matter before combustion (fuel + air) and all matter produced after combustion (flue gas) are equal in mass. Since the main component of the fuel gas is methane, its combustion consumes oxygen from the air. Therefore, given a fixed fuel gas composition, based on the chemical reaction equation for combustion, the composition of air (e.g., oxygen accounts for 20.9%), and the law of conservation of mass, the concentration of unused residual oxygen in the flue gas is related to the combustion conditions. For example, if the residual oxygen concentration is 0%, it corresponds to ideal combustion; if the residual oxygen concentration is 2%, there is a slight excess of air (corresponding to efficient combustion); if the residual oxygen concentration is 10%, it indicates a significant excess of air (corresponding to inefficient combustion); and if the residual oxygen concentration is close to 20.9%, it indicates that the flame is about to extinguish or has already extinguished. Therefore, the monitored oxygen concentration can directly reflect the combustion status (i.e., determine the combustion status based on the degree of oxygen consumption in the air), and thus a mapping relationship can be established between the oxygen concentration characterizing the combustion status and the ratio of gas flow rate to air flow rate.

[0100] In some embodiments, the ratio of gas flow rate to air flow rate can be obtained by querying a preset mapping table based on oxygen concentration.

[0101] In some embodiments, determining whether the combustion flame has extinguished due to flame lift-off based on the ratio of the gas flow rate to the air flow rate may include the following steps:

[0102] S20, determine whether the ratio of the gas flow rate to the air flow rate meets the preset conditions;

[0103] Preset conditions are pre-defined criteria or threshold ranges. When the ratio of gas flow rate to air flow rate meets these conditions, it indicates that the combustion flame is at risk of flameout. Preset conditions can be set based on combustion experiment data, such as when the ratio of gas flow rate to air flow rate exceeds the safe range.

[0104] In some embodiments, the preset conditions include the ratio of gas flow rate to air flow rate continuously decreasing within a preset time period, or the ratio of gas flow rate to air flow rate being lower than a preset threshold.

[0105] The preset time period is a pre-defined time interval used to monitor the changing trend of the ratio of gas flow to air flow. The unit can be seconds or minutes. The preset time period defines the duration window for trend analysis. For example, setting the preset time period to 10 seconds means checking the change in the ratio of gas flow to air flow over the last 10 seconds.

[0106] "Continuous decrease" refers to the trend of the ratio of gas flow rate to air flow rate decreasing over a preset time period, meaning the ratio of gas flow rate to air flow rate decreases continuously. In practical applications, the ratio of gas flow rate to air flow rate is typically around 0.8 during normal operation of a gas-fired heating and hot water boiler.

[0107] The preset threshold is a pre-defined critical value for the ratio of gas flow to air flow. When the ratio of gas flow to air flow is lower than the preset threshold, it indicates an abnormal mixing ratio. The preset threshold refers to a lower limit value, which can be set based on safety standards. For example, setting the preset threshold to 0.5 will automatically trigger flameout protection when the ratio of gas flow to air flow (i.e., Qg / Qa) reaches 0.5, as the blockage worsens.

[0108] S21, if so, confirm that the combustion flame has extinguished.

[0109] In some embodiments, determining whether the combustion flame has extinguished due to flame lift-off based on the ratio of the gas flow rate to the air flow rate may further include the following operations:

[0110] S30, determine whether the ratio of the gas flow rate to the air flow rate meets the preset conditions;

[0111] S31, If ​​yes, detect the flame signal intensity of the combustion flame;

[0112] Detection is the action of measuring physical quantities and collecting data through a sensor system.

[0113] Flame signal intensity is a physical quantity measurement that reflects the state and stability of a combustion flame. Flame characteristics can be converted into electrical signals by a flame sensor.

[0114] In some embodiments, detecting the flame signal intensity of the combustion flame includes: acquiring a flame current signal at a preset sampling frequency through the controller; and performing a moving average filter on the acquired flame current signal to obtain the flame signal intensity of the combustion flame.

[0115] A controller (also known as a control system) is an electronic control unit in a gas-fired heating and hot water boiler. It processes sensor signals, executes control algorithms, and outputs commands to operate actuators. A controller may include a microprocessor, memory, and input / output interfaces. For example, a microcontroller-based circuit board receives flame sensor signals and controls a pneumatic gas valve.

[0116] The preset sampling frequency is the signal acquisition rate pre-set by the controller, representing the number of times the signal is sampled per unit time. The commonly used unit is Hertz (Hz). The preset sampling frequency determines the data acquisition time interval and affects signal accuracy.

[0117] The flame current signal is an electrical signal output by the flame sensor. It can be in the form of current and reflects the degree of ionization or light intensity of the combustion flame. The signal magnitude is related to the flame intensity.

[0118] Moving average filtering is a digital signal processing technique that smooths a signal by calculating the arithmetic mean of multiple consecutive data points in a signal sequence, reducing the impact of random noise. Moving average filtering uses a fixed-length data window that slides as new data is added. For example, a moving average with a window size of 5 is used to average every 5 consecutive samples.

[0119] The flame signal intensity of the combustion flame is a stable signal value obtained after moving average filtering, which represents the average intensity level of the flame and is used to reliably determine the flame state.

[0120] S32, when the flame signal intensity is less than a preset flame intensity threshold, determine that the combustion flame is extinguished by flame removal.

[0121] The preset flame intensity threshold is a pre-set minimum safety limit, representing the minimum flame signal intensity required to maintain stable combustion. When the flame signal intensity is below this threshold, it indicates that the flame energy is insufficient or has been extinguished.

[0122] In some embodiments, before determining whether the ratio of the gas flow rate to the air flow rate meets a preset condition, the method includes: obtaining the fan speed of the hot water boiler; and increasing the fan speed until it reaches the maximum speed based on the gradual decrease in the ratio of the gas flow rate to the air flow rate. That is, based on maintaining the actual required combustion heat load, the fan speed needs to be increased until the maximum speed is reached.

[0123] Fan speed is the number of revolutions the fan shaft makes per unit time, representing the fan's operating speed. The commonly used unit is revolutions per minute (rpm). Fan speed directly affects the air supply. For example, during normal operation of a hot water boiler, the fan rotates at 2000 revolutions per minute.

[0124] The maximum speed can be the highest speed limit that the fan can reach under safe operating conditions, and it is determined by the fan design parameters and controller protection settings. For example, the maximum speed of the fan is 7000 revolutions per minute.

[0125] Step 103: In response to the flame extinguishing upon flame lift-off, the pneumatic gas valve is closed via the controller.

[0126] In some embodiments, after determining that the flameout has occurred, the controller can immediately generate a shutdown signal (such as a power-off signal or a digital command) and send it to the electromagnetic drive assembly of the pneumatic gas valve to quickly close the valve to cut off the gas supply and prevent gas leakage.

[0127] Reference Figure 2 The diagram shown is a functional module schematic of the gas-fired heating and hot water boiler flameout control system 200 of this application.

[0128] The gas-fired heating and hot water boiler flameout control system 200 described in this application is installed in an electronic device. Depending on the functions it performs, the gas-fired heating and hot water boiler flameout control system 200 includes a debugging module 210, a determination module 220, and a control module 230. These modules can also be referred to as units, which are a series of computer program segments that can be executed by the processor of an electronic device and perform a fixed function, and are stored in the memory of the electronic device.

[0129] In this embodiment, the functions of each module / unit are as follows:

[0130] The debugging module 210 is used to set the zero-position adjusting spring pressure Os of the pneumatic gas valve's control valve to a negative value during the overall machine debugging stage.

[0131] The determining module 220 is used to determine whether the combustion flame has detached and extinguished based on the ratio of gas flow rate to air flow rate during the operation of the hot water boiler; wherein, when the zero-position adjusting spring pressure Os is negative and the combustion system is sealed, the degree of flame detachment is negatively correlated with the magnitude of the ratio of gas flow rate to air flow rate.

[0132] The control module 230 is used to close the pneumatic gas valve via a controller in response to the flame extinguishing.

[0133] The specific implementation method of the gas-fired heating and hot water boiler flameout control system of this application is largely the same as the specific implementation method of the gas-fired heating and hot water boiler flameout control method described above, and will not be repeated here.

[0134] Figure 3 This is an exemplary structural diagram of a combustion system for a gas-fired heating and hot water boiler provided in an embodiment of this application.

[0135] like Figure 3 As shown, the combustion system of the gas-fired heating and hot water boiler includes an air purification chamber 3, an air connection pipe 4, a Venturi premixing chamber 6, and a pneumatic gas valve 7. The inlet of the air purification chamber 3 is sealed to the end of the flue pipe via a flue pipe adapter, and the outlet of the air purification chamber 3 is sealed to the air inlet of the Venturi premixing chamber 6 via the air connection pipe 4. The gas outlet of the pneumatic gas valve 7 is sealed to the gas inlet of the Venturi premixing chamber 6. The flue pipe, the air purification chamber 3, the air connection pipe 4, the Venturi premixing chamber 6, and the air inlet of the DC fan are sequentially connected, forming a closed airflow channel from the outside to the DC fan 9. For more information on the flue pipe, flue pipe adapter, and DC fan, please refer to [link to relevant documentation]. Figure 4 .

[0136] The core of the combustion system provided in this application embodiment lies in the construction of a completely sealed airflow channel. Outdoor air is first drawn in through the flue pipe 1. The end of the flue pipe 1 is connected to the inlet of the air purification chamber 3 via a flue pipe adapter 2. The bottom of the air purification chamber 3 is designed with a water collection groove (not shown in the figure) to collect rainwater that may flow back from the flue pipe 1. An air filter can also be installed inside the air purification chamber 3 to filter dust and other impurities in the air. The outlet of the air purification chamber 3 is connected to the air inlet of the Venturi premixing chamber 6 via an air connection pipe 4.

[0137] A Venturi mixer is installed inside the Venturi premixing chamber 6. The gas outlet of the pneumatic gas valve 7 is connected to the gas inlet of the Venturi premixing chamber 6, injecting gas into it. Air and gas are fully premixed here. The mixed gas is drawn in by the DC fan 9 and sent to the fully premixed burner (not shown in the diagram) for combustion. The high-temperature flue gas generated by combustion flows through a heat exchanger (not shown in the diagram) to transfer heat to the heating system or domestic water supply, and is finally discharged outdoors through the flue pipe 1.

[0138] In some embodiments, the gas-fired heating and hot water boiler further includes an air pressure pipe 5, one end of which is connected to the air purification chamber 3, and the other end is connected to the air pressure interface of the control valve of the pneumatic gas valve 7.

[0139] In some embodiments, the air purification chamber 3 is provided with a pressure hole, and one end of the air pressure pipe 5 is connected to the pressure hole of the air purification chamber 3. The air in the air purification chamber 3 can enter the control valve of the pneumatic gas valve 7 through the air pressure pipe 5, so that the diaphragm of the control valve of the pneumatic gas valve 7 can sense the change in air pressure in the air purification chamber 3. Combined with the relevant derivation of formulas (1)-(5) above, the pneumatic gas valve is controlled to close when the flue is blocked, so as to play the role of flue blockage protection when the whole machine is shut down.

[0140] To achieve a closed flow channel, all connections are reliably sealed using seals. For example, one end of the air pressure pipe 5 is sealed to the pressure port of the air purification chamber 3 via a seal.

[0141] In some embodiments, the outlet of the air purification chamber 3 is sealed to one end of the air connection pipe 4 via a seal; the other end of the air connection pipe 4 is sealed to the air inlet of the Venturi premixing chamber 6 via the seal.

[0142] In some embodiments, the connection points between the flue adapter 2 and the flue 1 and the air purification chamber 3, the connection points between the air purification chamber 3 and the air connecting pipe 4, and the connection points between the air connecting pipe 4 and the Venturi premixing chamber 6 are all connected by sealing elements.

[0143] In some embodiments, the seal is a cylindrical structure, for example, a cylindrical rubber sealing ring with good elasticity and aging resistance.

[0144] Figure 4 This is an exemplary structural diagram of a gas-fired heating and hot water boiler provided in an embodiment of this application. Figure 4 As shown, in Figure 3Based on the combustion system shown, the gas-fired heating and hot water boiler also includes a control system 8, a bottom cover 10, and a top cover. The control system 8 is used to control the valve of the pneumatic gas valve 7, and can control the pneumatic gas valve to close when the flue pipe is blocked, so as to play a role in flue pipe blockage protection when the whole unit is shut down.

[0145] The combustion system and other components of the gas-fired heating and hot water boiler can be installed together in the space formed by the bottom cover 10 and the top cover.

[0146] Reference Figure 5 The diagram shown is a schematic representation of a preferred embodiment of the electronic device of this application.

[0147] The electronic device includes a processor 111, a communication interface 112, a memory 113, and a communication bus 114, wherein the processor 111, the communication interface 112, and the memory 113 communicate with each other through the communication bus 114.

[0148] The memory 113 is used to store computer programs, such as the flameout control program for a gas-fired heating hot water boiler;

[0149] In some embodiments, the processor 111 may be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip. The processor 111 can be used to control the overall operation of the electronic device, such as performing data interaction or communication-related control and processing. In this embodiment, the processor 111 is used to run program code stored in the memory 113 or process data.

[0150] The communication interface 112 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface). The communication interface 112 may also be used to establish a communication connection between the electronic device and other electronic devices.

[0151] The memory 113 includes at least one type of readable storage medium, including flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, magnetic disk, optical disk, etc. In some embodiments, the memory 113 may be an internal storage unit of the electronic device, such as the hard disk or memory of the electronic device. In other embodiments, the memory 113 may also be an external storage device of the electronic device, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc. of the electronic device. Of course, the memory 113 may include both internal storage units and external storage devices of the electronic device. In this embodiment, the memory 113 can be used to store the operating system and various computer programs installed on the electronic device, such as the program code of the flameout control program for a gas-fired heating hot water boiler. In addition, the memory 113 can also be used to temporarily store various types of data that have been output or will be output.

[0152] Figure 5 Only an electronic device with components 111-114 is shown; however, it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0153] In one embodiment of this application, the processor 111, when executing the program stored in the memory 113, implements the gas-fired heating hot water boiler flameout control method provided in any of the foregoing method embodiments, including:

[0154] During the overall machine debugging phase, the zero-position adjusting spring pressure Os of the pneumatic gas valve's control valve is set to a negative value.

[0155] During the operation of the hot water boiler, the combustion flame is determined to be extinguished based on the ratio of gas flow rate to air flow rate; wherein, when the zero-position adjusting spring pressure Os is negative and the combustion system is sealed, the degree of flame extinguishing is negatively correlated with the magnitude of the ratio of gas flow rate to air flow rate.

[0156] In response to the flame extinguishing upon flame lift-off, the pneumatic gas valve is closed via the controller.

[0157] For a detailed explanation of the above steps, please refer to the above. Figure 1 Description of the flowchart of the embodiment of the flameout control method for gas-fired heating and hot water boilers.

[0158] Furthermore, this application also proposes a computer-readable storage medium that is both non-volatile and volatile. This computer-readable storage medium is any one or any combination of several of the following: hard disk, multimedia card, SD card, flash memory card, SMC, read-only memory (ROM), erasable programmable read-only memory (EPROM), portable compact disc read-only memory (CD-ROM), USB memory, etc. The computer-readable storage medium includes a data storage area and a program storage area. The program storage area stores a gas-fired heating hot water boiler flameout control program. When executed by a processor, the gas-fired heating hot water boiler flameout control program performs the following operations:

[0159] During the overall machine debugging phase, the zero-position adjusting spring pressure Os of the pneumatic gas valve's control valve is set to a negative value.

[0160] During the operation of the hot water boiler, the combustion flame is determined to be extinguished based on the ratio of gas flow rate to air flow rate; wherein, when the zero-position adjusting spring pressure Os is negative and the combustion system is sealed, the degree of flame extinguishing is negatively correlated with the magnitude of the ratio of gas flow rate to air flow rate.

[0161] In response to the flame extinguishing upon flame lift-off, the pneumatic gas valve is closed via the controller.

[0162] The specific implementation of the computer-readable storage medium in this application is largely the same as the specific implementation of the above-described gas-fired heating and hot water boiler flameout control method, and will not be repeated here.

[0163] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, system, article, or method that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, system, article, or method. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, system, article, or method that includes that element.

[0164] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware simulation platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0165] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method of controlling the extinguishing of a gas-fired heating water heater, characterized in that, The gas-fired heating and hot water boiler includes a sealed combustion system, a Venturi mixer, and a pneumatic gas valve connected in sequence. The pilot valve of the pneumatic gas valve is connected to the air purification chamber of the sealed combustion system via an air pressure pipe. The method includes: During the overall machine debugging phase, the zero-position adjusting spring pressure Os of the pneumatic gas valve's control valve is set to a negative value. During the operation of the gas-fired heating and hot water boiler, the combustion flame is determined to be extinguished based on the ratio of gas flow rate to air flow rate; wherein, when the zero-position adjusting spring pressure Os is negative and the sealed combustion system is sealed, the degree of flame extinguishing is negatively correlated with the ratio of gas flow rate to air flow rate. In response to the flame extinguishing upon flame lift-off, the pneumatic gas valve is closed via the controller.

2. The method of claim 1, wherein the method further comprises: The ratio of the gas flow rate to the air flow rate is determined in the following way: The oxygen concentration after flame combustion is monitored by a sensor installed in the flue of the gas-fired heating and hot water boiler. Based on a preset mapping table and the oxygen concentration, the ratio of the gas flow rate to the air flow rate is determined.

3. The flameout control method for a gas-fired heating and hot water boiler according to claim 1, characterized in that, Determining whether the combustion flame has extinguished due to flame lift-off based on the ratio of the gas flow rate to the air flow rate includes: Determine whether the ratio of the gas flow rate to the air flow rate meets a preset condition; If so, confirm that the combustion flame has extinguished upon removal from the flame.

4. The flameout control method for a gas-fired heating and hot water boiler according to claim 2, characterized in that, Determining whether the combustion flame has extinguished due to flame lift-off based on the ratio of the gas flow rate to the air flow rate includes: Determine whether the ratio of the gas flow rate to the air flow rate meets a preset condition; If so, detect the intensity of the flame signal of the combustion flame; When the flame signal intensity is less than a preset flame intensity threshold, the combustion flame is determined to extinguish.

5. The flameout control method for a gas-fired heating and hot water boiler according to claim 4, characterized in that, The detection of the flame signal intensity of the combustion flame includes: The controller acquires flame current signals at a preset sampling frequency. The collected flame current signal is filtered by moving average to obtain the flame signal intensity of the combustion flame.

6. The flameout control method for a gas-fired heating hot water boiler according to claim 3 or 4, characterized in that, Before determining whether the ratio of the gas flow rate to the air flow rate meets a preset condition, the method includes: Obtain the fan speed of the hot water boiler; As the ratio of gas flow rate to air flow rate gradually decreases, the fan speed is increased until it reaches the maximum speed.

7. The flameout control method for a gas-fired heating hot water boiler according to claim 3 or 4, characterized in that, The preset conditions include the ratio of gas flow rate to air flow rate continuously decreasing within a preset time period or the ratio of gas flow rate to air flow rate being lower than a preset threshold.

8. A flameout control system for a gas-fired heating and hot water boiler, characterized in that, The gas-fired heating and hot water boiler includes a sealed combustion system, a Venturi mixer, and a pneumatic gas valve connected in sequence. The pilot valve of the pneumatic gas valve is connected to the air purification chamber of the sealed combustion system via an air pressure pipe. The system includes: The debugging module is used to set the zero-position adjusting spring pressure Os of the pneumatic gas valve's control valve to a negative value during the overall machine debugging phase. The determination module is used to determine whether the combustion flame has detached and extinguished based on the ratio of gas flow rate to air flow rate during the operation of the gas-fired heating and hot water boiler; wherein, when the zero-position adjusting spring pressure Os is negative and the sealed combustion system is sealed, the degree of flame detachment is negatively correlated with the magnitude of the ratio of gas flow rate to air flow rate. The control module is used to close the pneumatic gas valve via a controller in response to the flame extinguishing.

9. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; The processor, when executing a program stored in a memory, implements the flameout control method for a gas-fired heating hot water boiler as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the flameout control method for a gas-fired heating hot water boiler as described in any one of claims 1 to 7.

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