Gas-fired boiler hydrogen-doped self-adaptive regulation and control system and method based on flue gas carbon and oxygen monitoring

Abstract

The invention provides a gas-fired boiler hydrogen-doped self-adaptive regulation and control system and method based on flue gas carbon and oxygen monitoring, and relates to the technical field of gas-fired boilers. According to the system, the carbon dioxide concentration and the oxygen concentration in the flue gas of the gas-fired boiler are obtained, the actual hydrogen doping proportion and the excess air coefficient are determined on the basis of the carbon dioxide concentration and the oxygen concentration in the flue gas, and then the nozzle pressure and the fan rotating speed of the gas-fired boiler are controlled on the basis of the actual hydrogen doping proportion and the excess air coefficient; namely, the gas flow and the blast volume of the gas-fired boiler are automatically adjusted, and the stability of the heat load and the heat efficiency of the boiler is maintained. According to the system provided by the invention, the intelligent level of the gas boiler and the self-adaptive capacity of coping with hydrogen doping proportion fluctuation can be effectively improved, and the use difficulty and cost of a user are reduced, so that the use requirements of the user in different use scenes can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of gas boilers, and in particular to a gas boiler hydrogen blending adaptive control system and method based on flue gas carbon and oxygen monitoring. Background Art

[0002] With the adjustment of energy structure and the improvement of environmental protection requirements, hydrogen-blended natural gas has gradually attracted attention as a clean energy. However, after switching to hydrogen-blended natural gas, gas boilers need to adjust the gas flow and air supply to ensure heat load and thermal efficiency due to the change in fuel calorific value. Most existing control methods rely on preset programs or manual adjustments, and cannot adapt to changes in hydrogen blending ratios in real time and accurately.

[0003] In the related art, there are already some control systems and methods for hydrogen-doped gas equipment. For example, CN117267758A provides an automatic control device for improving the thermal efficiency of hydrogen-doped natural gas stoves. The device is provided with a hydrogen-doped control module and a height adjustment module. The hydrogen-doped control module is used to control the hydrogen-doped ratio of the mixed gas. The height adjustment module is used to adjust the height between the pot and the stove, and control the gas flow through the primary and secondary pipelines. The hydrogen-doped control module and the height adjustment module transmit signals to the master control module, which is used to control the hydrogen-doped control module and the height adjustment module. The operator inputs the preset hydrogen-doped ratio and temperature on the control panel, and the central processor receives the signal, adjusts the solenoid valve and the flowmeter, and transmits the information of the thermocouple at the bottom of the pot to the central processor. The central processor controls the motor of the height adjustment device and the two-way regulating valve, and improves the thermal efficiency of the stove by adjusting the height between the pot and the stove and controlling the hydrogen-doped ratio. CN117685665A proposes a control method for a hydrogen-adapted gas wall-mounted boiler and a gas wall-mounted boiler. The method obtains the parameters such as the hydrogen admixture ratio and gas flow rate of the gas, calculates the input power of the wall-mounted boiler under the corresponding hydrogen admixture ratio, and calculates the optimal air-fuel ratio of the wall-mounted boiler based on these parameters. After comparing with the current air-fuel ratio, the fan and gas proportional valve of the wall-mounted boiler are adjusted to obtain the optimal combustion condition and realize precise control of the wall-mounted boiler. Although these patents provide control systems and methods for hydrogen-admixed gas equipment, they do not completely solve the problem of intelligent control of hydrogen-admixed natural gas combustion in gas equipment, or although they can adapt to the hydrogen admixture ratio, they need to obtain the hydrogen admixture ratio through multiple adjustments of the gas flow rate and the fan air volume, and cannot realize real-time adaptation to different hydrogen admixture ratios based on monitoring data.

[0004] Therefore, there is an urgent need for a gas boiler hydrogen blending adaptive control system and method based on flue gas carbon oxygen monitoring, which can realize real-time control of the gas hydrogen blending ratio and meet the user's usage needs in different usage scenarios. Summary of the invention

[0005] The embodiments of the present invention provide a gas boiler hydrogen blending adaptive control system and method based on flue gas carbon oxygen monitoring, which can achieve real-time control of the hydrogen blending ratio of the gas to meet the user's usage needs in different usage scenarios.

[0006] To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

[0007] In a first aspect, a gas boiler hydrogen blending adaptive control system based on flue gas carbon oxygen monitoring is provided, which is applied to a gas boiler. The system comprises: a monitoring module, an analysis module and a control module, wherein the output end of the monitoring module is connected to the input end of the analysis module, the output end of the analysis module is connected to the input end of the control module, and the control module is connected to a nozzle controller and a fan of the gas boiler; the monitoring module comprises a first sensor and a second sensor, the first sensor and the second sensor are arranged at the furnace outlet of the gas boiler, the first sensor is used to obtain the oxygen concentration in the flue gas of the gas boiler, and the second sensor is used to obtain the carbon dioxide concentration in the flue gas of the gas boiler; the analysis module is used to determine the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler according to the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler, and is used to determine the nozzle pressure change ratio of the gas boiler according to the actual hydrogen blending ratio of the gas of the gas boiler; the analysis module is used to control the nozzle pressure of the gas boiler according to the nozzle pressure change ratio of the gas boiler, and is used to control the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, so that the excess air coefficient of the gas boiler is within a first preset interval.

[0008] In a possible implementation of the first aspect, a formula for determining an actual hydrogen blending ratio and an excess air coefficient of the gas of the gas boiler is:

[0009] (1-n) / [(1-n)+(4.76α-1)(2-1.5α)]=X CO2 ;

[0010] (α-1)(2-1.5n) / [(1-n)+(4.76α-1)(2-1.5α)]=X O2 ;

[0011] Among them, n is the actual hydrogen blending ratio of the gas boiler's fuel gas, α is the excess air coefficient of the gas boiler's fuel gas, and X CO2 is the carbon dioxide concentration in the flue gas of the gas boiler; X O2 is the oxygen concentration in the flue gas of the gas boiler.

[0012] In a possible implementation of the first aspect, the nozzle pressure change ratio f P The formula for determining is:

[0013] f P =(1-0.876n0 )(1-0.7n 0 ) 2 / (1-0.876n)(1-0.7n) 2 ;

[0014] Among them, n 0 The preset hydrogen blending ratio for the gas of the gas boiler.

[0015] In a possible implementation of the first aspect, the first preset interval is greater than or equal to a and less than or equal to b. When the control module is used to control the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, the control module is specifically used to: when the excess air coefficient of the gas boiler is less than a, increase the fan speed of the gas boiler; when the excess air coefficient of the gas boiler is greater than b, reduce the fan speed of the gas boiler; when the excess air coefficient of the gas boiler is greater than or equal to a and less than or equal to b, keep the fan speed of the gas boiler unchanged.

[0016] In a possible implementation of the first aspect, the analysis module is also used to: generate a first alarm message when the oxygen concentration and / or carbon dioxide concentration in the flue gas of the gas boiler is not within a second preset range, the first alarm message being used to indicate that the concentration of a component of the flue gas is abnormal; and display the first alarm message.

[0017] In a possible implementation of the first aspect, the analysis module is further configured to: receive fault information, the fault information being used to indicate a fault of the first sensor, the second sensor, the nozzle controller, and / or the fan; generate second alarm information in response to the fault information, the second alarm information being used to indicate a fault of the first sensor, the second sensor, the nozzle controller, and / or the fan; and display the second alarm information.

[0018] The beneficial effects of the present invention are as follows: the system provided by the present invention obtains the carbon dioxide concentration and oxygen concentration in the flue gas of the gas boiler, determines the actual hydrogen blending ratio and the excess air coefficient based on the carbon dioxide concentration and oxygen concentration in the flue gas, and then controls the nozzle pressure and fan speed of the gas boiler based on the actual hydrogen blending ratio and the excess air coefficient, that is, automatically adjusts the gas flow and blast volume of the gas boiler to maintain the stability of the boiler's thermal load and thermal efficiency. The system provided by the present invention can effectively improve the intelligence level of the gas boiler and its adaptive ability to cope with fluctuations in the hydrogen blending ratio, reduce the user's difficulty and cost, and thus meet the user's usage needs in different usage scenarios.

[0019] In a second aspect, an embodiment of the present invention provides a method for adaptively controlling hydrogen blending in a gas boiler based on flue gas carbon oxygen monitoring, characterized in that, when applied to a gas boiler, the method includes: obtaining the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler; determining the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler according to the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler; determining the nozzle pressure change ratio of the gas boiler according to the actual hydrogen blending ratio of the gas of the gas boiler; controlling the nozzle pressure of the gas boiler according to the nozzle pressure change ratio of the gas boiler, and controlling the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, so that the excess air coefficient of the gas boiler is within a first preset range.

[0020] In a possible implementation of the second aspect, a formula for determining an actual hydrogen blending ratio and an excess air coefficient of the gas of the gas boiler is:

[0021] (1-n) / [(1-n)+(4.76α-1)(2-1.5α)]=X CO2 ;

[0022] (α-1)(2-1.5n) / [(1-n)+(4.76α-1)(2-1.5α)]=X O2 ;

[0023] Among them, n is the actual hydrogen blending ratio of the gas boiler's fuel gas, α is the excess air coefficient of the gas boiler's fuel gas, and X CO2 is the carbon dioxide concentration in the flue gas of the gas boiler; X O2 is the oxygen concentration in the flue gas of the gas boiler;

[0024] Nozzle pressure change ratio f P The formula for determining is:

[0025] f P =(1-0.876n 0 )(1-0.7n 0 ) 2 / (1-0.876n)(1-0.7n) 2 ;

[0026] Among them, n 0 The preset hydrogen blending ratio for the gas of the gas boiler.

[0027] In a possible implementation of the second aspect, the first preset interval is greater than or equal to a and less than or equal to b, and the fan speed of the gas boiler is controlled according to the excess air coefficient of the gas boiler, including: when the excess air coefficient of the gas boiler is less than a, increasing the fan speed of the gas boiler; when the excess air coefficient of the gas boiler is greater than b, reducing the fan speed of the gas boiler; when the excess air coefficient of the gas boiler is greater than or equal to a and less than or equal to b, keeping the fan speed of the gas boiler unchanged.

[0028] In a possible implementation of the second aspect, after obtaining the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler, the method further includes: when the oxygen concentration and / or carbon dioxide concentration in the flue gas of the gas boiler is not within the second preset interval, generating a first alarm message, the first alarm message being used to indicate that the concentration of a component of the flue gas is abnormal; and displaying the first alarm message.

[0029] It can be understood that the beneficial effects that can be achieved by the method of the second aspect provided above can refer to the beneficial effects in the first aspect and any possible design thereof, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the hardware structure of a control system shown in an embodiment of the present invention;

[0031] Figure 2 A schematic diagram of the hardware structure of a control system shown in an embodiment of the present invention;

[0032] Figure 3 A flow chart of a method for adaptively controlling hydrogen blending in a gas boiler based on flue gas carbon and oxygen monitoring is shown in an embodiment of the present invention;

[0033] Figure 4 The present invention is a flowchart of another method for adaptively controlling hydrogen blending in a gas boiler based on flue gas carbon and oxygen monitoring according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The technical solution in the embodiment of the present invention will be described below in conjunction with the accompanying drawings in the embodiment of the present invention. Among them, in the description of the present invention, unless otherwise specified, " / " indicates that the objects associated before and after are in an "or" relationship, for example, A / B can represent A or B; "and / or" in the present invention is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. And, in the description of the present invention, unless otherwise specified, "multiple" means two or more than two. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items.

[0035] In addition, in order to clearly describe the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, the words "first", "second", etc. are used to distinguish the same items or similar items with substantially the same functions and effects. Those skilled in the art can understand that the words "first", "second", etc. do not limit the quantity and execution order, and the words "first", "second", etc. do not necessarily limit the difference.

[0036] Meanwhile, in the embodiments of the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way for easy understanding.

[0037] With the adjustment of energy structure and the improvement of environmental protection requirements, hydrogen-blended natural gas has gradually attracted attention as a clean energy. However, after switching to hydrogen-blended natural gas, gas boilers need to adjust the gas flow and air supply to ensure heat load and thermal efficiency due to the change in fuel calorific value. Most existing control methods rely on preset programs or manual adjustments, and cannot adapt to changes in hydrogen blending ratios in real time and accurately.

[0038] In the related art, there are already some control systems and methods for hydrogen-doped gas equipment. For example, CN117267758A provides an automatic control device for improving the thermal efficiency of hydrogen-doped natural gas stoves. The device is provided with a hydrogen-doped control module and a height adjustment module. The hydrogen-doped control module is used to control the hydrogen-doped ratio of the mixed gas. The height adjustment module is used to adjust the height between the pot and the stove, and control the gas flow through the primary and secondary pipelines. The hydrogen-doped control module and the height adjustment module transmit signals to the master control module, which is used to control the hydrogen-doped control module and the height adjustment module. The operator inputs the preset hydrogen-doped ratio and temperature on the control panel, and the central processor receives the signal, adjusts the solenoid valve and the flowmeter, and transmits the information of the thermocouple at the bottom of the pot to the central processor. The central processor controls the motor of the height adjustment device and the two-way regulating valve, and improves the thermal efficiency of the stove by adjusting the height between the pot and the stove and controlling the hydrogen-doped ratio. CN117685665A proposes a control method for a hydrogen-adapted gas wall-mounted boiler and a gas wall-mounted boiler. The method obtains the parameters such as the hydrogen admixture ratio and gas flow rate of the gas, calculates the input power of the wall-mounted boiler under the corresponding hydrogen admixture ratio, and calculates the optimal air-fuel ratio of the wall-mounted boiler based on these parameters. After comparing with the current air-fuel ratio, the fan and gas proportional valve of the wall-mounted boiler are adjusted to obtain the optimal combustion condition and realize precise control of the wall-mounted boiler. Although these patents provide control systems and methods for hydrogen-admixed gas equipment, they do not completely solve the problem of intelligent control of hydrogen-admixed natural gas combustion in gas equipment, or although they can adapt to the hydrogen admixture ratio, they need to obtain the hydrogen admixture ratio through multiple adjustments of the gas flow rate and the fan air volume, and cannot realize real-time adaptation to different hydrogen admixture ratios based on monitoring data.

[0039] Therefore, there is an urgent need for a gas boiler hydrogen blending adaptive control system and method based on flue gas carbon oxygen monitoring, which can realize real-time control of the gas hydrogen blending ratio and meet the user's usage needs in different usage scenarios.

[0040] In view of this, an embodiment of the present invention provides a gas boiler hydrogen blending adaptive control system based on flue gas carbon oxygen monitoring, which is applied to a gas boiler. The system includes: a monitoring module, an analysis module and a control module, wherein the output end of the monitoring module is connected to the input end of the analysis module, the output end of the analysis module is connected to the input end of the control module, and the control module is connected to the nozzle controller and the fan of the gas boiler; the monitoring module includes a first sensor and a second sensor, the first sensor and the second sensor are arranged at the furnace outlet of the gas boiler, the first sensor is used to obtain the oxygen concentration in the flue gas of the gas boiler, and the second sensor is used to obtain the carbon dioxide concentration in the flue gas of the gas boiler; the analysis module is used to determine the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler according to the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler, and is used to determine the nozzle pressure change ratio of the gas boiler according to the actual hydrogen blending ratio of the gas of the gas boiler; the analysis module is used to control the nozzle pressure of the gas boiler according to the nozzle pressure change ratio of the gas boiler, and is used to control the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, so that the excess air coefficient of the gas boiler is within a first preset interval.

[0041] The system provided by the present invention obtains the carbon dioxide concentration and oxygen concentration in the flue gas of the gas boiler, determines the actual hydrogen blending ratio and the excess air coefficient based on the carbon dioxide concentration and oxygen concentration in the flue gas, and then controls the nozzle pressure and fan speed of the gas boiler based on the actual hydrogen blending ratio and the excess air coefficient, that is, automatically adjusts the gas flow and blast volume of the gas boiler to maintain the stability of the boiler's thermal load and thermal efficiency. The system provided by the present invention can effectively improve the intelligence level of the gas boiler and its adaptive ability to cope with fluctuations in the hydrogen blending ratio, reduce the user's difficulty and cost, and thus meet the user's usage needs in different usage scenarios.

[0042] See also Figure 1 , Figure 1 The hardware structure diagram of a gas boiler hydrogen blending adaptive control system based on flue gas carbon and oxygen monitoring is shown in an embodiment of the present invention. The gas boiler hydrogen blending adaptive control system 100 based on flue gas carbon and oxygen monitoring (hereinafter referred to as the control system 100) includes a monitoring module 110, an analysis module 120 and a control module 130. The output end of the monitoring module 110 is connected to the input end of the analysis module 120, the output end of the analysis module 120 is connected to the input end of the control module 130, and the control module 130 is connected to the nozzle controller 210 and the fan 220 of the gas boiler 200.

[0043] The monitoring module 110 includes a first sensor 111 and a second sensor 112, which are arranged at the furnace outlet of the gas boiler 200. The first sensor 111 is used to obtain the oxygen concentration in the flue gas of the gas boiler, and the second sensor 112 is used to obtain the carbon dioxide concentration in the flue gas of the gas boiler.

[0044] The analysis module 120 is used to determine the actual hydrogen blending ratio and excess air coefficient of the gas boiler's fuel gas according to the oxygen concentration and carbon dioxide concentration in the gas boiler's flue gas, and to determine the nozzle pressure change ratio of the gas boiler according to the actual hydrogen blending ratio of the gas boiler's fuel gas.

[0045] In some embodiments, the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler are determined by the formula:

[0046] (1-n) / [(1-n)+(4.76α-1)(2-1.5α)]=X CO2 ;

[0047] (α-1)(2-1.5n) / [(1-n)+(4.76α-1)(2-1.5α)]=X O2 ;

[0048] Among them, n is the actual hydrogen blending ratio of the gas boiler's fuel gas, α is the excess air coefficient of the gas boiler's fuel gas, and X CO2 is the carbon dioxide concentration in the flue gas of the gas boiler; X O2 is the oxygen concentration in the flue gas of the gas boiler.

[0049] For ease of understanding, the formula for determining the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler is described below.

[0050] The chemical equilibrium equation for the combustion reaction of hydrogen-doped natural gas is:

[0051] (1-n)CH 4 +nH 2 +α(2-1.5n)O 2 +3.76α(2-1.5n)N 2 =(1-n)CO 2 +(2-n)H 2 O+(α-1)(2-1.5n)O 2 +3.76α(2-1.5n)N 2 ;

[0052] Then we get equation 1 and equation 2.

[0053] Equation 1: (1-n) / [(1-n)+(4.76α-1)(2-1.5α)]=XCO2 ;

[0054] Equation 2: (α-1)(2-1.5n) / [(1-n)+(4.76α-1)(2-1.5α)]=X O2 ;

[0055] Among them, X CO2 is the dry volume concentration of carbon dioxide, X O2 is the volume concentration of oxygen on a dry basis.

[0056] By combining the above equations 1 and 2, the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler are obtained.

[0057] In one possible implementation, the nozzle pressure change ratio f P The formula for determining is:

[0058] f P =(1-0.876n 0 )(1-0.7n 0 ) 2 / (1-0.876n)(1-0.7n) 2 ;

[0059] Among them, n 0 The preset hydrogen blending ratio for the gas of the gas boiler.

[0060] Specifically, the calorific value change rate f of the actual combustion calorific value and the preset combustion calorific value of the gas boiler is determined based on the preset hydrogen blending ratio and the actual hydrogen blending ratio of the gas of the gas boiler. H .

[0061] f H =H / H 0 =(1-0.7n) / (1-0.7n 0 ).

[0062] When the gas flow rate of the gas boiler is V and the boiler heat load is Q, according to the heat load calculation formula, in order to keep the heat load of the gas boiler unchanged after the hydrogen blending ratio changes, the calorific value change rate f H The determination formula is used to obtain the current natural gas flow rate V and the flow rate V under the preset heat load 0 The ratio of the fuel flow rate change rate f V .

[0063] Among them, the heat load calculation formula is: Q = H × V;

[0064] Fuel flow rate change rate f V The formula for determining f is: V =V / V 0 =1 / f H .

[0065] Assuming the gas pressure before the burner is p, the nozzle resistance coefficient is η, the gas density is ρ, and the nozzle outlet cross-sectional area is F, the relationship between the gas pressure before the burner and the gas flow rate is as shown in the following formula. When the burner structure does not change, the gas flow rate is only related to the gas density and gas pressure.

[0066] pη=38642V 2 ρ / F 2

[0067] Then, the gas density ρ under the actual hydrogen blending ratio and the gas density ρ under the preset hydrogen blending ratio are obtained according to the following formula: 0 According to the fuel gas pressure formula, the flow rate adjustment change rate f after the hydrogen blending ratio changes V and the gas density change rate f ρ In order to keep the heat load constant, the formula for determining the rate of change fp that the pressure before the nozzle needs to meet is:

[0068] f P =(1-0.876n 0 )(1-0.7n 0 ) 2 / (1-0.876n)(1-0.7n) 2 .

[0069] The analysis module 130 is used to control the nozzle pressure of the gas boiler according to the nozzle pressure change ratio of the gas boiler, and to control the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, so that the excess air coefficient of the gas boiler is within a first preset range.

[0070] In some embodiments, the first preset interval is greater than or equal to a and less than or equal to b. When the control module 130 is used to control the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, the control module 130 is specifically used to: when the excess air coefficient of the gas boiler is less than a, increase the fan speed of the gas boiler; when the excess air coefficient of the gas boiler is greater than b, reduce the fan speed of the gas boiler; when the excess air coefficient of the gas boiler is greater than or equal to a and less than or equal to b, keep the fan speed of the gas boiler unchanged.

[0071] It is to be understood that the structure shown in this embodiment does not constitute a specific limitation on the control system 100. In other embodiments of the present invention, the control system 100 may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0072] From the above, it can be seen that the system provided by the present invention obtains the carbon dioxide concentration and oxygen concentration in the flue gas of the gas boiler, determines the actual hydrogen blending ratio and excess air coefficient based on the carbon dioxide concentration and oxygen concentration in the flue gas, and then controls the nozzle pressure and fan speed of the gas boiler based on the actual hydrogen blending ratio and excess air coefficient, that is, automatically adjusts the gas flow and blast volume of the gas boiler to maintain the stability of the boiler's thermal load and thermal efficiency. The system provided by the present invention can effectively improve the intelligence level of the gas boiler and its adaptive ability to cope with fluctuations in the hydrogen blending ratio, reduce the user's difficulty and cost, and thus meet the user's usage needs in different usage scenarios.

[0073] In some embodiments, the analysis module 120 is also used to: generate a first alarm message when the oxygen concentration and / or carbon dioxide concentration in the flue gas of the gas boiler is not within the second preset range, the first alarm message being used to indicate that the concentration of the components of the flue gas is abnormal; and display the first alarm message.

[0074] In some embodiments, the analysis module 120 is further used to: receive fault information, the fault information is used to indicate the fault of the first sensor, the second sensor, the nozzle controller and / or the fan; generate second alarm information in response to the fault information, the second alarm information is used to indicate the fault of the first sensor, the second sensor, the nozzle controller and / or the fan; and display the second alarm information.

[0075] For details, see Figure 2 The analysis module 120 is further configured with a display unit 121, and the display unit 121 is used to display the first alarm information and the second alarm information.

[0076] As can be seen from the above, the first alarm information and the second alarm information can enable the user to quickly understand the fault condition of the gas boiler and handle it in time to avoid safety accidents.

[0077] Optionally, the display unit 121 is also used to display a preset hydrogen blending ratio, an actual hydrogen blending ratio, an excess air coefficient, a nozzle pressure and a fan speed of the gas of the gas boiler.

[0078] In this way, the user can quickly and accurately understand the operation status of the gas boiler in real time through the content displayed by the display unit 121, which can effectively improve the user's experience.

[0079] The following describes the gas boiler hydrogen blending adaptive control method based on flue gas carbon and oxygen monitoring provided by an embodiment of the present invention in conjunction with the accompanying drawings.

[0080] Figure 3 The flowchart of a method for adaptively controlling hydrogen blending in a gas boiler based on flue gas carbon and oxygen monitoring provided by an embodiment of the present invention is as follows. Optionally, the method can be Figure 1 or Figure 2 The control system 100 shown is implemented and applied to a gas boiler. The method may include the following steps:

[0081] S1. Obtain the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler.

[0082] In one possible implementation, see Figure 4 After the above S1, the method provided by the embodiment of the present invention further includes:

[0083] S11. When the oxygen concentration and / or carbon dioxide concentration in the flue gas of the gas boiler is not within the second preset range, generate first alarm information, where the first alarm information is used to indicate that the concentration of components in the flue gas is abnormal.

[0084] S12. Display the first alarm information.

[0085] As can be seen from the above, the first alarm information enables the user to quickly understand the fault condition of the gas boiler and handle it in time to avoid safety accidents.

[0086] S2. Determine the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler according to the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler.

[0087] The formula for determining the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler is:

[0088] (1-n) / [(1-n)+(4.76α-1)(2-1.5α)]=X CO2 ;

[0089] (α-1)(2-1.5n) / [(1-n)+(4.76α-1)(2-1.5α)]=X O2 ;

[0090] Among them, n is the actual hydrogen blending ratio of the gas boiler's fuel gas, α is the excess air coefficient of the gas boiler's fuel gas, and X CO2 is the carbon dioxide concentration in the flue gas of the gas boiler; X O2 is the oxygen concentration in the flue gas of the gas boiler.

[0091] S3. Determine the nozzle pressure change ratio of the gas boiler according to the actual hydrogen blending ratio of the gas of the gas boiler.

[0092] Nozzle pressure change ratio f P The formula for determining is:

[0093] f P =(1-0.876n 0 )(1-0.7n 0 ) 2 / (1-0.876n)(1-0.7n) 2 ;

[0094] Among them, n 0 The preset hydrogen blending ratio for the gas of the gas boiler.

[0095] It should be noted that the actual determination process of the actual hydrogen blending ratio, the excess air coefficient and the nozzle pressure change ratio is detailed in the description of the above embodiment and will not be repeated here.

[0096] S4. Controlling the nozzle pressure of the gas boiler according to the nozzle pressure change ratio of the gas boiler, and controlling the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, so that the excess air coefficient of the gas boiler is within a first preset range.

[0097] In some embodiments, the first preset interval is greater than or equal to a and less than or equal to b, and the fan speed of the gas boiler is controlled according to the excess air coefficient of the gas boiler, including:

[0098] When the excess air coefficient of the gas boiler is less than a, the fan speed of the gas boiler is increased; when the excess air coefficient of the gas boiler is greater than b, the fan speed of the gas boiler is reduced; when the excess air coefficient of the gas boiler is greater than or equal to a, and less than or equal to b, the fan speed of the gas boiler is kept unchanged.

[0099] In one example, a is 1.1 and b is 1.2.

[0100] As can be seen from the above S1-S4, the method provided by the present invention obtains the carbon dioxide concentration and oxygen concentration in the flue gas of the gas boiler, determines the actual hydrogen blending ratio and the excess air coefficient based on the carbon dioxide concentration and oxygen concentration in the flue gas, and then controls the nozzle pressure and fan speed of the gas boiler based on the actual hydrogen blending ratio and the excess air coefficient, that is, automatically adjusts the gas flow and blast volume of the gas boiler to maintain the stability of the boiler's thermal load and thermal efficiency. The method provided by the present invention can effectively improve the intelligence level of the gas boiler and its adaptive ability to cope with fluctuations in the hydrogen blending ratio, reduce the user's difficulty and cost, and thus meet the user's usage needs in different usage scenarios.

[0101] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A gas boiler hydrogen blending adaptive control system based on flue gas carbon and oxygen monitoring, characterized in that: Applied to a gas boiler, the system comprises: a monitoring module, an analysis module and a control module, the output end of the monitoring module is connected to the input end of the analysis module, the output end of the analysis module is connected to the input end of the control module, and the control module is connected to the nozzle controller and the fan of the gas boiler; The monitoring module includes a first sensor and a second sensor, the first sensor and the second sensor are arranged at the furnace outlet of the gas boiler, the first sensor is used to obtain the oxygen concentration in the flue gas of the gas boiler, and the second sensor is used to obtain the carbon dioxide concentration in the flue gas of the gas boiler; The analysis module is used to determine the actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler according to the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler, and is used to determine the nozzle pressure change ratio of the gas boiler according to the actual hydrogen blending ratio of the gas of the gas boiler; The analysis module is used to control the nozzle pressure of the gas boiler according to the change ratio of the nozzle pressure of the gas boiler, and is used to control the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, so that the excess air coefficient of the gas boiler is within a first preset range.

2. The system according to claim 1, characterized in that The actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler are determined by the following formula: (1-n) / [(1-n)+(4.76α-1)(2-1.5α)]=X CO2 ; (α-1)(2-1.5n) / [(1-n)+(4.76α-1)(2-1.5α)]=X O2 ; Wherein, n is the actual hydrogen blending ratio of the gas of the gas boiler, α is the excess air coefficient of the gas of the gas boiler, and X CO2 is the carbon dioxide concentration in the flue gas of the gas boiler; O2 is the oxygen concentration in the flue gas of the gas boiler.

3. The system according to claim 2, characterized in that The nozzle pressure change ratio f P The formula for determining is: in P =(1-0.876n0)(1-0.7n0) 2 / (1-0.876n)(1-0.7n) 2 ; Wherein, n0 is the preset hydrogen blending ratio of the gas of the gas boiler.

4. The system according to claim 3, characterized in that The first preset interval is greater than or equal to a and less than or equal to b. When the control module is used to control the fan speed of the gas boiler according to the excess air coefficient of the gas boiler, the control module is specifically used to: When the excess air coefficient of the gas boiler is less than a, increasing the fan speed of the gas boiler; When the excess air coefficient of the gas boiler is greater than b, reducing the fan speed of the gas boiler; When the excess air coefficient of the gas boiler is greater than or equal to a and less than or equal to b, the fan speed of the gas boiler is kept unchanged.

5. The system according to claim 4, characterized in that The analysis module is further used for: When the oxygen concentration and / or carbon dioxide concentration in the flue gas of the gas boiler is not within the second preset range, generating a first alarm message, wherein the first alarm message is used to indicate that the concentration of the components of the flue gas is abnormal; Display the first alarm information.

6. The system according to claim 5, characterized in that The analysis module is further used for: Receiving fault information, wherein the fault information is used to indicate a fault of the first sensor, the second sensor, the nozzle controller and / or the fan; In response to the fault information, generating second alarm information, wherein the second alarm information is used to indicate a fault of the first sensor, the second sensor, the nozzle controller and / or the fan; Display the second alarm message.

7. A method for adaptively controlling hydrogen blending in a gas boiler based on flue gas carbon and oxygen monitoring, characterized in that: Applied to a gas boiler, the method comprises: Obtaining the oxygen concentration and carbon dioxide concentration in the flue gas of the gas boiler; Determining an actual hydrogen blending ratio and an excess air coefficient of the gas of the gas boiler according to the oxygen concentration and the carbon dioxide concentration in the flue gas of the gas boiler; Determining a nozzle pressure change ratio of the gas boiler according to an actual hydrogen blending ratio of the gas of the gas boiler; The nozzle pressure of the gas boiler is controlled according to the nozzle pressure change ratio of the gas boiler, and the fan speed of the gas boiler is controlled according to the excess air coefficient of the gas boiler, so that the excess air coefficient of the gas boiler is within a first preset range.

8. The method according to claim 7, characterized in that The actual hydrogen blending ratio and excess air coefficient of the gas of the gas boiler are determined by the following formula: (1-n) / [(1-n)+(4.76α-1)(2-1.5α)]=X CO2 ; (α-1)(2-1.5n) / [(1-n)+(4.76α-1)(2-1.5α)]=X O2 ; Wherein, n is the actual hydrogen blending ratio of the gas of the gas boiler, α is the excess air coefficient of the gas of the gas boiler, and X CO2 is the carbon dioxide concentration in the flue gas of the gas boiler; O2 is the oxygen concentration in the flue gas of the gas boiler; The nozzle pressure change ratio f P The formula for determining is: in P =(1-0.876n0)(1-0.7n0) 2 / (1-0.876n)(1-0.7n) 2 ; Wherein, n0 is the preset hydrogen blending ratio of the gas of the gas boiler.

9. The method according to claim 8, characterized in that The first preset interval is greater than or equal to a and less than or equal to b, and the fan speed of the gas boiler is controlled according to the excess air coefficient of the gas boiler, including: When the excess air coefficient of the gas boiler is less than a, increasing the fan speed of the gas boiler; When the excess air coefficient of the gas boiler is greater than b, reducing the fan speed of the gas boiler; When the excess air coefficient of the gas boiler is greater than or equal to a and less than or equal to b, the fan speed of the gas boiler is kept unchanged.

10. The method according to claim 9, characterized in that After obtaining the oxygen concentration and the carbon dioxide concentration in the flue gas of the gas boiler, the method further includes: When the oxygen concentration and / or carbon dioxide concentration in the flue gas of the gas boiler is not within the second preset range, generating a first alarm message, wherein the first alarm message is used to indicate that the concentration of the components of the flue gas is abnormal; Display the first alarm information.

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