A deflagration detection method, device and equipment of a gas water heating device

Abstract

This application provides a method, apparatus, and device for detecting deflagration in a gas-fired water heater, relating to the field of deflagration detection technology. The method includes, in response to a start-up command from the gas-fired water heater, acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater. These combustion characteristic parameters include wind pressure surge characteristic parameters and / or flame ionization signal surge characteristic parameters. When the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to preset combustion characteristic parameters, it is determined that deflagration has occurred in the gas-fired water heater, effectively detecting deflagration phenomena during the ignition process.

Description

Technical Field

[0001] This application relates to the field of deflagration detection technology, and in particular to a deflagration detection method, apparatus and equipment for gas-fired hot water equipment. Background Technology

[0002] Gas appliances such as gas water heaters and gas-fired boilers typically require ignition control during startup and flame monitoring to determine successful ignition. In actual use, if gas accumulates briefly in the combustion chamber and is then ignited, deflagration may occur. After deflagration, on the one hand, the initial ignition may fail to establish a stable flame, requiring the appliance to undergo a secondary ignition process. On the other hand, even if the appliance detects a flame signal within a short time, the flame may be extinguished by the instantaneous airflow generated by the deflagration, causing the appliance to repeatedly attempt ignition.

[0003] Traditional gas appliance ignition detection typically focuses on whether a flame is detected and whether the conditions for successful ignition are met, making it difficult to distinguish between normal ignition fluctuations, unstable ordinary ignition, and deflagration impacts. When deflagration is not effectively identified, the gas appliance may attempt secondary ignition after the deflagration, increasing the risk of re-deflagration and reducing the safety of gas water heaters.

[0004] Therefore, there is an urgent need for a deflagration detection method for gas-fired water heaters to solve the problem that traditional gas appliance ignition detection methods cannot effectively detect deflagration during the ignition process of gas appliances. Summary of the Invention

[0005] The purpose of this application is to provide a method, device, and equipment for detecting deflagration in gas-fired water heaters, which can effectively detect deflagration during the ignition process of gas-fired water heaters.

[0006] In a first aspect, embodiments of this application provide a method for detecting deflagration in a gas-fired water heater. The method includes: in response to a start-up command from the gas-fired water heater, acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater, wherein the combustion characteristic parameters include wind pressure change characteristic parameters and / or flame ionization signal change characteristic parameters. When the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to preset combustion characteristic parameters, it is determined that deflagration has occurred in the gas-fired water heater.

[0007] The deflagration detection method for gas-fired water heaters provided in this application involves a sudden pressure surge caused by the intense combustion of gas in the combustion chamber during ignition. This leads to a significant change in wind pressure, and the instantaneous high temperature and airflow impact from the deflagration cause a significant change in the flame ionization electrical signal. Combustion characteristic parameters during the ignition process are acquired, including wind pressure change characteristic parameters, flame ionization electrical signal change characteristic parameters, or a combination of both. These parameters are then compared with preset combustion characteristic parameters. If the combustion characteristic parameters during the ignition process do not match the preset parameters, deflagration is determined to have occurred. This invention provides multiple detection dimensions for determining deflagration, allowing for rapid determination using a single parameter or improved accuracy through multi-parameter comprehensive determination. Upon detection of deflagration, the gas-fired water heater can promptly implement corresponding control measures (such as stopping secondary ignition or executing safety protection procedures). Therefore, the method of this invention effectively detects deflagration during the ignition process of gas-fired water heaters, improving their operational safety.

[0008] One possible implementation involves using combustion characteristic parameters including wind pressure surge characteristic parameters, which include the wind pressure rise. Obtaining the combustion characteristic parameters during the ignition process of the gas-fired water heater includes: acquiring the steady-state wind pressure value before ignition and the peak wind pressure value after ignition. The wind pressure rise is determined based on the difference between the steady-state wind pressure value and the peak wind pressure value.

[0009] One possible implementation involves determining that a deflagration has occurred in a gas-fired water heater when the combustion characteristic parameters during the ignition process do not conform to preset combustion characteristic parameters. This includes comparing the increase in air pressure with a preset increase in air pressure. If the increase in air pressure is determined to be greater than the preset increase in air pressure, a deflagration is determined to have occurred in the gas-fired water heater.

[0010] One possible implementation method includes further specifying the wind pressure change per unit time as a characteristic parameter for sudden wind pressure changes. This involves acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater, including: acquiring the ignition time of the gas-fired water heater and the peak occurrence time corresponding to the peak wind pressure. Based on the peak occurrence time and the ignition time of the gas-fired water heater, the duration of the wind pressure rise is determined. Finally, based on the amount of wind pressure rise and the duration of the wind pressure rise, the change in wind pressure per unit time is determined.

[0011] One possible implementation involves determining that a deflagration has occurred in a gas-fired water heater when the combustion characteristic parameters during the ignition process do not conform to preset combustion characteristic parameters. This includes comparing the change in air pressure per unit time with a preset change in air pressure per unit time. If the change in air pressure per unit time is greater than the preset change in air pressure per unit time, a deflagration is determined to have occurred in the gas-fired water heater.

[0012] One possible implementation involves combustion characteristic parameters including flame ionization signal abrupt change characteristic parameters, which include a first flame ionization signal change amount, a flame ionization signal rebound duration, and a flame ionization signal recovery duration. Acquiring combustion characteristic parameters during the ignition process of a gas-fired water heater includes: acquiring flame ionization signal detection data during the ignition process; determining, based on the flame ionization signal detection data, a first extreme detection value formed by the flame ionization signal detection value after flame detection, and a first time point corresponding to the first extreme detection value; determining, based on the flame ionization signal detection data, a second extreme detection value formed by the change in the flame ionization signal detection value after the first extreme detection value, and a second time point corresponding to the second extreme detection value; determining, based on the flame ionization signal detection data, a third extreme detection value formed by the change in the flame ionization signal detection value after the second extreme detection value, and a third time point corresponding to the third extreme detection value; determining the first flame ionization signal change amount based on the difference between the first and second extreme detection values; and determining the flame ionization signal abrupt change duration based on the first and second time points. The recovery time of the flame ion electrical signal is determined based on the second and third time points.

[0013] One possible implementation involves determining that deflagration has occurred in a gas-fired water heater when the combustion characteristic parameters during the ignition process do not conform to preset combustion characteristic parameters. This includes comparing the change in a first flame ionization signal with a preset change in a flame ionization signal, comparing the duration of a sudden change in the flame ionization signal with a preset sudden change duration, and comparing the recovery time of the flame ionization signal with a preset recovery time. If it is determined that the change in the first flame ionization signal is greater than the preset change in the flame ionization signal, the duration of a sudden change in the flame ionization signal is less than the preset sudden change duration, and the recovery time of the flame ionization signal is less than the preset recovery time, then deflagration is determined to have occurred in the gas-fired water heater.

[0014] One possible implementation method includes, as a whole, the flame ionization electrical signal abrupt change characteristic parameters further comprising the first flame ionization electrical signal unit-time change, the second flame ionization electrical signal unit-time change, and the third flame ionization electrical signal unit-time change. Acquiring combustion characteristic parameters during the ignition process of a gas-fired water heater includes: acquiring the ignition time of the gas-fired water heater; determining the duration of the first signal change based on the second time and the ignition time; determining the unit-time change of the first flame ionization electrical signal based on the first flame ionization electrical signal change and the first signal change duration; determining the unit-time change of the second flame ionization electrical signal based on the first flame ionization electrical signal change and the flame ionization electrical signal abrupt change duration; determining the second flame ionization electrical signal change based on the difference between the second extreme value detection value and the third extreme value detection value; and determining the unit-time change of the third flame ionization electrical signal based on the second flame ionization electrical signal change and the flame ionization electrical signal recovery time.

[0015] One possible implementation involves determining that deflagration has occurred in a gas-fired water heater when the combustion characteristic parameters during the ignition process do not conform to preset combustion characteristic parameters. This includes comparing the unit-time changes of the first, second, and third flame ionization electrical signals with corresponding preset unit-time changes of flame ionization electrical signals. If the unit-time changes of the first, second, and third flame ionization electrical signals are all greater than the corresponding preset unit-time changes of flame ionization electrical signals, then deflagration is determined to have occurred in the gas-fired water heater.

[0016] One possible implementation involves combustion characteristic parameters including wind pressure surge characteristic parameters and flame ionization electrical signal surge characteristic parameters. When the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to preset combustion characteristic parameters, deflagration is determined to have occurred. This includes: acquiring the moment when the wind pressure peak occurs after ignition and the second moment corresponding to the second extreme value detected by the change in the flame ionization electrical signal detection value. Based on the moment of the wind pressure peak occurrence and the second moment, the time difference between the wind pressure surge and the flame ionization electrical signal surge is determined. If the wind pressure surge characteristic parameters do not conform to preset wind pressure surge characteristic parameters, the flame ionization electrical signal surge characteristic parameters do not conform to preset flame ionization electrical signal surge characteristic parameters, and the time difference is less than a preset synchronization time difference, deflagration is determined to have occurred in the gas-fired water heater.

[0017] One possible implementation involves obtaining the steady-state air pressure value before ignition of the gas-fired water heater, including: controlling the fan of the gas-fired water heater to operate at a preset ignition speed. Once it is determined that the fan operation meets stable conditions, the steady-state air pressure value before ignition of the gas-fired water heater is obtained, and the gas-fired water heater is then controlled to ignite.

[0018] Secondly, embodiments of this application provide a deflagration detection device for a gas-fired water heater, the device comprising: an acquisition module, a determination module, a judgment module, and a control module.

[0019] The acquisition module is used to acquire combustion characteristic parameters during the ignition process of the gas water heater in response to the start command of the gas water heater. The combustion characteristic parameters include wind pressure change characteristic parameters and / or flame ionization signal change characteristic parameters.

[0020] The determination module is used to determine that the gas water heater has deflagration when the combustion characteristic parameters during the ignition process do not meet the preset combustion characteristic parameters.

[0021] Thirdly, this application provides a gas-fired water heater, which includes a processor and a memory. The memory stores machine-executable instructions that can be executed by the processor, and the processor executes the machine-executable instructions to implement the above-mentioned deflagration detection method for the gas-fired water heater. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 A schematic diagram of a gas-fired water heater provided in an embodiment of this application; Figure 2 A flowchart illustrating a deflagration detection method for a gas-fired water heater provided in this application embodiment; Figure 3 A schematic diagram of a deflagration detection device for a gas-fired water heater provided in this application embodiment; Figure 4 This is a system architecture diagram of a deflagration detection system for a gas-fired water heater provided in an embodiment of this application. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0026] In the ignition control process of gas appliances, traditional ignition detection methods typically rely on whether a flame is detected, whether the flame persists, and whether ignition is successful within a preset time as the main criteria for judgment. While these methods can identify common anomalies such as ignition failure and accidental flameout, they often lack specific identification logic for the deflagration impact caused by the short-term accumulation and ignition of gas at the moment of ignition. During deflagration, a momentary pressure surge occurs in the combustion chamber, which may cause a sudden increase in air pressure and unstable changes in flame detection values, such as rapid rebounds and drops. If treated as a normal ignition failure or flame fluctuation, the gas appliance may attempt to ignite again before the combustion chamber state has recovered and the cause of the anomaly has been eliminated, increasing the risks of secondary deflagration, impact on combustion components, abnormal vibration of the flue or combustion chamber, and user risks. Therefore, relying solely on the presence or absence of a flame or successful ignition is insufficient to promptly and accurately distinguish between normal ignition fluctuations and deflagration impacts, and it is also difficult to take timely protective measures such as prohibiting re-ignition and issuing fault warnings after a deflagration occurs.

[0027] Based on this, embodiments of this application provide a method, apparatus, and device for detecting deflagration in a gas-fired water heater. The method includes, in response to a start-up command from the gas-fired water heater, acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater. These combustion characteristic parameters include wind pressure surge characteristic parameters and / or flame ionization signal surge characteristic parameters. When the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to preset combustion characteristic parameters, it is determined that deflagration has occurred in the gas-fired water heater.

[0028] The deflagration detection method for gas-fired water heaters provided in this application addresses the issue of deflagration during ignition. When deflagration occurs, the intense, instantaneous combustion of gas in the combustion chamber causes a sudden pressure surge, resulting in a significant change in wind pressure. Simultaneously, the instantaneous high temperature and airflow impact generated by deflagration cause significant changes in the flame ionization electrical signal. By acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater, including one or more of wind pressure change characteristic parameters and flame ionization electrical signal change characteristic parameters, abnormal combustion states during ignition can be detected from different dimensions. This allows for rapid determination using a single type of combustion characteristic parameter or a comprehensive determination using multiple combustion characteristic parameters, thereby improving the accuracy of deflagration detection. Furthermore, the combustion characteristic parameters are compared with preset combustion characteristic parameters. If the combustion characteristic parameters do not conform to the preset parameters, deflagration is determined to have occurred, enabling the gas-fired water heater to promptly implement control measures such as stopping secondary ignition, safety protection, or fault indication. This effectively detects deflagration during ignition and improves the safety of the gas-fired water heater.

[0029] The methods provided in the embodiments of this application will now be described in conjunction with the specific accompanying drawings.

[0030] On one hand, this application provides a gas-fired water heating device 100. This gas-fired water heating device 100 can be a gas water heater or a gas-fired wall-mounted boiler. For example... Figure 1 As shown, the gas-fired water heater 100 includes: a fan 101, a burner 102, a main valve 103, an igniter 104, a wind pressure sensor 105, a flame ionization signal detection component 106, and a controller 107.

[0031] The fan 101 drives air to flow within the duct of the gas-fired hot water equipment 100, providing the burner 102 with the necessary air for combustion before ignition or during electric ignition. The burner 102 is connected to the gas supply passage to mix the gas with air for combustion. The main valve 103 is located on the gas supply passage and controls whether gas enters the burner 102. The igniter 104 generates an electric spark to ignite the gas entering the burner 102.

[0032] The wind pressure sensor 105 is used to detect changes in air pressure within the duct of the gas-fired water heater 100. The installation location of the wind pressure sensor 105 is not limited to a single location, as long as the installation location can detect changes in air pressure within the duct caused by ignition, combustion, or deflagration impact.

[0033] For example, the wind pressure sensor 105 can be installed at the venturi structure of the fan 101, or at the fan inlet, fan outlet, or other locations that can reflect changes in the wind pressure in the duct.

[0034] The flame ionization electrical signal detection component 106 is used to detect the flame state at the burner 102 and output flame ionization electrical signal detection data corresponding to the flame state. For example, the flame ionization electrical signal detection component 106 may include a flame ionization detection needle and a flame detection circuit connected to the flame ionization detection needle. Correspondingly, after a flame is formed in the burner 102, the flame ionization detection needle generates a flame ionization electrical signal based on the ion conductivity effect of the flame. The flame detection circuit acquires and converts this flame ionization electrical signal to obtain the corresponding flame ionization electrical signal detection value.

[0035] The controller 107 is connected to the fan 101, the main valve 103, the igniter 104, the air pressure sensor 105, and the flame ionization electrical signal detection component 106. The controller 107 can respond to the start command of the gas water heater 100 using the deflagration detection method for gas water heaters provided in this application embodiment, controlling the fan 101, the igniter 104, and the main valve 103 to operate according to a preset ignition process, and acquiring detection data during the ignition process through the air pressure sensor 105 and the flame ionization electrical signal detection component 106.

[0036] Furthermore, the controller 107 obtains wind pressure abrupt change characteristic parameters such as wind pressure increase and wind pressure change per unit time based on the data collected by the wind pressure sensor 105, and obtains flame ion electrical signal abrupt change characteristic parameters such as flame ion electrical signal change, flame ion electrical signal abrupt change duration, flame ion electrical signal recovery duration, and corresponding change per unit time based on the data collected by the flame ion electrical signal detection component 106. Based on the comparison results between the corresponding combustion characteristic parameters and preset combustion characteristic parameters, the controller 107 determines whether deflagration occurs in the gas water heater 100 during the ignition process.

[0037] On one hand, embodiments of this application provide a method for detecting deflagration in a gas-fired water heater. This method can be performed by... Figure 1 The gas-fired water heater 100 shown is in operation. Figure 2 As shown, the method may include the following steps.

[0038] S201, in response to the start command of the gas water heater, acquires the combustion characteristic parameters during the ignition process of the gas water heater.

[0039] Specifically, after receiving a demand for domestic hot water, heating, or other combustion, the gas-fired water heater first enters the ignition preparation process. In this process, the gas-fired water heater first checks the operating status of the fan, main valve, igniter, air pressure sensor, and flame detection components. If the relevant components are operating normally, it generates a start command for the gas-fired water heater, and then initiates the ignition process based on this start command.

[0040] One possible implementation is to control the fan of the gas water heater to run at a preset ignition speed before the gas water heater starts the ignition process; and after confirming that the fan operation meets the stable conditions, obtain the steady-state value of the air pressure before the gas water heater is ignited, and then control the gas water heater to ignite.

[0041] Specifically, when the main valve is closed, the fan is operating normally, the air pressure sensor is outputting an air pressure signal, the flame ionization electrical signal detection component is outputting a detection signal, and the gas water heater is not in a fault-locked state, it can be determined that the gas water heater currently meets the pre-ignition safety conditions. At this time, the control fan runs at the preset ignition speed to clean the combustion chamber and air duct before ignition, and establishes the air supply state corresponding to this ignition within the air duct.

[0042] Meanwhile, during fan operation, fan speed and air pressure readings are continuously acquired. When the actual fan speed reaches the preset ignition speed and remains stable within a preset time period, the fan operation is deemed to meet the stability conditions. Fan operation stability can also be determined by considering fluctuations in air pressure readings; for example, if the variation between multiple consecutively acquired air pressure readings within a preset time period is less than a preset fluctuation range, the fan operation is deemed to meet the stability conditions.

[0043] After confirming that the fan operation meets the stability conditions, obtain the steady-state value of the air pressure before the ignition of the gas-fired water heater. Specifically, a single wind pressure reading can be collected after the fan reaches the preset ignition speed and operates stably, or multiple wind pressure readings can be collected continuously. The average of these multiple readings can then be calculated, filtered, or outlier removed to obtain the steady-state wind pressure value. Wind pressure steady-state value It is used to reflect the air pressure status in the air duct when the fan is running stably at the preset ignition speed and the gas water heater has not yet started ignition.

[0044] For example, after the fan reaches the preset ignition speed, a preset number of pre-ignition air pressure values ​​are continuously collected. When the maximum difference between multiple pre-ignition air pressure values ​​is less than a preset fluctuation threshold, the multiple pre-ignition air pressure values ​​are averaged to obtain the steady-state air pressure value. This reduces the impact of the wind turbine startup phase and instantaneous wind pressure fluctuations on subsequent deflagration detection results.

[0045] After achieving steady-state wind pressure values After obtaining the data, the igniter is activated and the ignition time of the gas-fired water heater is recorded. After a preset delay time has elapsed since the igniter started operating, the main valve is opened to allow gas to enter the burner and participate in ignition. For example, the main valve can be opened 0.5 seconds after the igniter starts operating.

[0046] At this point, the pre-ignition operational status test and wind pressure steady-state value acquisition of the gas-fired water heater are completed, and the gas-fired water heater enters the ignition process.

[0047] Furthermore, in response to the start command of the gas-fired water heater, during the ignition process, parameters that can reflect changes in the combustion state are detected to obtain the combustion characteristic parameters corresponding to this ignition process.

[0048] Combustion characteristic parameters are used to characterize abrupt changes in the combustion process of a gas-fired water heater relative to normal combustion conditions. These parameters may include one or both of the wind pressure abrupt change characteristic parameters and the flame ionization electrical signal abrupt change characteristic parameters. The wind pressure abrupt change characteristic parameters reflect the pressure shock generated by deflagration from pressure changes within the combustion chamber and air duct, while the flame ionization electrical signal abrupt change characteristic parameters reflect the impact of deflagration on the flame state from changes in the flame ionization electrical signal.

[0049] One possible implementation is that, when the combustion characteristic parameters include wind pressure change characteristic parameters, the wind pressure change characteristic parameters include the wind pressure increase. Obtaining the combustion characteristic parameters during the ignition process of the gas-fired water heater includes: obtaining the steady-state wind pressure value before ignition and the peak wind pressure value after ignition; and determining the wind pressure increase based on the difference between the steady-state wind pressure value and the peak wind pressure value.

[0050] Specifically, after the gas water heater is ignited, the wind pressure sensor continuously collects the wind pressure readings in the duct, and determines the peak wind pressure from the post-ignition wind pressure readings. Peak wind pressure It can be from the ignition time The maximum wind pressure value detected from the start to the end of the preset detection period. The preset detection period can cover the process of igniter starting, main valve opening, and flame establishment.

[0051] Based on wind pressure steady-state value Peak wind pressure The difference between them determines the amount of wind pressure increase. : .

[0052] Among them, wind pressure rise It reflects the increase in maximum pressure within the air duct after ignition relative to the stable pressure before ignition. Under normal ignition conditions, the fan has already established a relatively stable air supply before ignition; therefore, the air pressure after ignition typically revolves around the steady-state air pressure value. This causes fluctuations within a certain range. During a deflagration, the gas inside the combustion chamber burns violently for a short period, causing rapid expansion and pressure surges that are transmitted to the air duct, resulting in peak air pressure. A significant increase. Therefore, the increase in wind pressure. It can be used as a characteristic parameter of wind pressure change to characterize the pressure change generated during ignition.

[0053] Furthermore, the characteristic parameters of sudden wind pressure changes can also include the change in wind pressure per unit time. Obtaining combustion characteristic parameters during the ignition process of a gas-fired water heater also includes: obtaining the ignition time of the gas-fired water heater and the peak occurrence time corresponding to the peak wind pressure; determining the duration of wind pressure rise based on the peak occurrence time and the ignition time of the gas-fired water heater; and determining the change in wind pressure per unit time based on the amount of wind pressure rise and the duration of wind pressure rise.

[0054] Specifically, in determining the peak wind pressure At the same time, record the peak wind pressure. Corresponding peak occurrence time Based on the time of peak occurrence and ignition timing The time difference between them determines the duration of wind pressure rise. : .

[0055] Based on the increase in wind pressure Duration of wind pressure rise Determine the change in wind pressure per unit time : .

[0056] Among them, wind pressure rise It focuses on reflecting the magnitude of pressure changes, the change in wind pressure per unit time. Furthermore, the time elapsed for this pressure change is used to reflect the speed of the sudden change in wind pressure. The pressure shock generated by deflagration is characterized by its short duration and rapid pressure rise. Therefore, even if there are certain differences in the magnitude of wind pressure increase under different operating conditions, the change in wind pressure per unit time can be used to further characterize whether the wind pressure change has obvious instantaneous change characteristics.

[0057] For example, during normal ignition, gas-fired water heaters may experience changes in air pressure due to adjustments in fan operation or variations in flue resistance; however, these pressure changes typically develop slowly. In the event of deflagration, the air pressure can rapidly reach its peak value within a short period. Therefore, the amount of air pressure increase... and the change in wind pressure per unit time The characteristic parameters of sudden wind pressure changes can be formed from two aspects: the magnitude of pressure change and the rate of pressure change.

[0058] Another possible implementation is that when the combustion characteristic parameters include flame ion electrical signal mutation characteristic parameters, the flame ion electrical signal mutation characteristic parameters include the first flame ion electrical signal change amount, the flame ion electrical signal mutation duration, and the flame ion electrical signal recovery duration.

[0059] The method for acquiring combustion characteristic parameters during the ignition process of a gas-fired water heater includes: acquiring flame ionization electrical signal detection data during the ignition process; determining, based on the flame ionization electrical signal detection data, the first extreme detection value formed by the flame ionization electrical signal detection value after flame detection, and the first time corresponding to the first extreme detection value; determining, based on the change in the flame ionization electrical signal detection value after the first extreme detection value, and the second time corresponding to the second extreme detection value; determining, based on the change in the flame ionization electrical signal detection value after the second extreme detection value, and the third time corresponding to the third extreme detection value; determining, based on the difference between the first and second extreme detection values, the first change in the flame ionization electrical signal; determining, based on the first and second times, the duration of the sudden change in the flame ionization electrical signal; and determining, based on the second and third times, the recovery time of the flame ionization electrical signal.

[0060] Specifically, during the ignition process, the flame ionization electrical signal detection component continuously collects flame ionization electrical signal detection data and identifies multiple extreme states based on the changes in the flame ionization electrical signal detection value over time.

[0061] After the flame is detected, the flame ionization electrical signal detection value changes first and forms the first extreme detection value. First extreme value detection value Corresponding to the first moment Subsequently, when the flame becomes unstable due to a momentary impact, the flame ionization signal detection value changes abruptly and forms a second extreme detection value. Second extreme value detection Corresponding to the second moment After the impact weakens, the flame state returns to normal, and the flame ion electrical signal detection value changes again, forming a third extreme detection value. Third extreme value Corresponding to the third moment .

[0062] For example, in a flame ionization signal detection circuit where the detection value decreases after flame is detected, the flame ionization signal detection value drops to a low level, or even to 0, after normal ignition, forming a first extreme detection value. When deflagration occurs during ignition, the flame becomes unstable due to the instantaneous high temperature and airflow impact. The detection value may rapidly rebound from 0 to 0xA1, forming a second extreme detection value. After the deflagration impact weakened, the detected value dropped again and formed a third extreme detected value. .

[0063] Based on the first extreme value detection value Second extreme value detection value The difference between them determines the change in the first flame ion electrical signal. In the second extreme value detection value Greater than the first extreme value detection value In the following circumstances: .

[0064] Among them, the change in the first flame ion electrical signal It is used to reflect the magnitude of change in the signal state of a flame when it changes from the signal state corresponding to normal combustion to the signal state after being subjected to deflagration impact.

[0065] According to the first moment Second moment Determine the duration of sudden changes in flame ion electrical signals : .

[0066] Among them, the duration of sudden changes in flame ion electrical signal Used to reflect the flame ionization electrical signal from the first extreme detection value Change to the second extreme value detection value The time elapsed.

[0067] According to the second moment and the third moment Determine the recovery time of the flame ion electrical signal. : .

[0068] Among them, the flame ion electrical signal recovery time Used to reflect the second extreme value of the flame ionization electrical signal after being impacted. The third extreme value corresponding to the change to the recovery state The time elapsed.

[0069] Furthermore, the characteristic parameters of the sudden change in flame ion electrical signal may also include the change in the first flame ion electrical signal per unit time, the change in the second flame ion electrical signal per unit time, and the change in the third flame ion electrical signal per unit time.

[0070] The combustion characteristic parameters during the ignition process of a gas-fired water heater are obtained, including: obtaining the ignition time of the gas-fired water heater; determining the duration of the first signal change based on the second time and the ignition time; determining the unit-time change of the first flame ion electrical signal based on the change in the first flame ion electrical signal and the duration of the first signal change; determining the unit-time change of the second flame ion electrical signal based on the change in the first flame ion electrical signal and the duration of the flame ion electrical signal abrupt change; determining the unit-time change of the second flame ion electrical signal based on the difference between the second extreme value detection value and the third extreme value detection value; and determining the unit-time change of the third flame ion electrical signal based on the change in the second flame ion electrical signal and the flame ion electrical signal recovery time.

[0071] Specifically, obtaining the ignition time of the gas-fired water heater. According to the second moment With ignition time The time difference between them determines the duration of the first signal change. : .

[0072] Based on the change in the first flame ion electrical signal Duration of change of the first signal Determine the change in the first flame ion electrical signal per unit time. : .

[0073] Among them, the change in the first flame ion electrical signal per unit time It is used to reflect the overall rate of change of the flame ion electrical signal from the start of ignition to the formation of the second extreme detection value.

[0074] Based on the change in the first flame ion electrical signal Duration of sudden changes in flame ion electrical signal Determine the unit time change of the second flame ion electrical signal. : .

[0075] Among them, the change in the second flame ion electrical signal per unit time It is used to reflect the abrupt change rate of the flame from the first extreme detection value to the second extreme detection value after the flame is impacted.

[0076] Based on the second extreme value detection value and the third extreme value detection value The difference between them determines the change in the second flame ion electrical signal. In the second extreme value detection value Greater than the third extreme value detection value In the following circumstances: .

[0077] Based on the change in the second flame ion electrical signal and flame ion electrical signal recovery time Determine the unit time change of the third flame ion electrical signal. : .

[0078] Among them, the change in the third flame ion electrical signal per unit time It is used to reflect the rate at which the flame ion electrical signal recovers from the second extreme detection value to the third extreme detection value.

[0079] The change in the first flame ion electrical signal per unit time The unit time change of the second flame ion electrical signal and the unit time change of the third flame ion electrical signal The impact of deflagration on the flame state can be described from different perspectives, such as the amplitude of signal change, the time of signal abrupt change, and the speed of signal change.

[0080] Another possible implementation is to simultaneously acquire wind pressure change characteristic parameters and flame ion electrical signal change characteristic parameters when the combustion characteristic parameters include both wind pressure change characteristic parameters and flame ion electrical signal change characteristic parameters during the ignition process, so as to determine the corresponding wind pressure change characteristic parameters and flame ion electrical signal change characteristic parameters respectively.

[0081] Specifically, on the wind pressure side, steady-state wind pressure values ​​can be obtained. Peak wind pressure and the time of peak occurrence And based on this, determine the wind pressure rise. Duration of wind pressure rise and the change in wind pressure per unit time The first extreme value can be obtained on the flame ionization electrical signal side. Second extreme value detection value Third extreme value detection value And the corresponding first moment Second moment and the third moment Based on this, the changes in the first flame ion electrical signal, the changes in the second flame ion electrical signal, the duration of the sudden change in the flame ion electrical signal, the duration of the recovery of the flame ion electrical signal, and the corresponding changes per unit time are determined.

[0082] Simultaneously record the peak occurrence time corresponding to the peak wind pressure. and the second time step corresponding to the second extreme value detection value This can provide a basis for subsequently determining the temporal correlation between sudden changes in wind pressure and sudden changes in flame ionization signals. Since the instantaneous and intense combustion caused by deflagration simultaneously causes sudden changes in combustion chamber pressure and flame state, by simultaneously acquiring the above two types of combustion characteristic parameters, the combustion anomalies during the ignition process of gas-fired water heaters can be characterized from two dimensions: pressure change and flame state change. This provides a data foundation for subsequent deflagration determination based on multiple combustion characteristic parameters.

[0083] S202, when the combustion characteristic parameters of the gas water heater during the ignition process do not meet the preset combustion characteristic parameters, it is determined that the gas water heater has deflagration.

[0084] Specifically, under normal ignition conditions in a gas-fired water heater, the changes in air pressure and flame ionization signal during ignition are typically within a relatively stable range. However, during deflagration, the gas accumulated in the combustion chamber burns violently and instantaneously. This causes a significant pressure surge, resulting in a rapid and substantial change in air pressure within the duct. Furthermore, the instantaneous high temperature and airflow impact generated by deflagration affect the flame, significantly altering its state and further causing abrupt changes in the flame ionization signal. Therefore, the combustion characteristic parameters during the ignition process of the gas-fired water heater can be compared with preset combustion characteristic parameters. Based on the comparison results, it can be determined whether the current combustion state deviates from the normal ignition state. If the combustion characteristic parameters deviate from the preset combustion characteristic parameters corresponding to the normal ignition state, deflagration can be identified as occurring in the gas-fired water heater.

[0085] The preset combustion characteristic parameters can be set according to the variation range of corresponding combustion characteristic parameters during normal ignition of the gas water heater. For example, for parameters that represent the amplitude or rate of change, such as the increase in air pressure, the change in air pressure per unit time, and the change in flame ionization electrical signal per unit time, corresponding upper limit thresholds can be set; for parameters that represent the duration of the change process, such as the abrupt change in flame ionization electrical signal and the recovery time of flame ionization electrical signal, corresponding duration thresholds can be set. When the corresponding combustion characteristic parameter exceeds the parameter range corresponding to normal ignition, it can be considered that the combustion characteristic parameter does not conform to the preset combustion characteristic parameters.

[0086] One possible implementation is to determine that the gas water heater has deflagration when the combustion characteristic parameters during the ignition process of the gas water heater do not conform to the preset combustion characteristic parameters, provided that the combustion characteristic parameters include the wind pressure change characteristic parameters and the wind pressure increase is included in the wind pressure change characteristic parameters. This includes: comparing the wind pressure increase with the preset wind pressure increase; and determining that the gas water heater has deflagration when the wind pressure increase is greater than the preset wind pressure increase.

[0087] Specifically, in S201, the steady-state value of the wind pressure before ignition has already been determined. Peak wind pressure after ignition The difference between them determines the amount of wind pressure increase. Since the fan is controlled to operate stably at the preset ignition speed before ignition, the air pressure in the duct is usually at its steady-state value during normal ignition. The corresponding normal range of variation. When deflagration occurs, the gas burns violently within a short period, and the rapidly expanding combustion gases create a pressure surge, significantly increasing the peak wind pressure after ignition. Therefore, when the wind pressure increases by a certain amount... When the wind pressure variation exceeds the allowable range during normal ignition, it can be determined that a significant wind pressure change occurred during the ignition process.

[0088] For example, the preset wind pressure rise can be set to 50 Pa. (The text abruptly ends here, seemingly mid-sentence.) If the pressure rise exceeds 50 Pa, it is determined that the pressure increase does not meet the preset pressure increase, and the gas-fired water heater is judged to have experienced deflagration. (The last sentence appears to be incomplete and possibly refers to a separate issue: "At the pressure rise...") If the pressure rise is no greater than 50 Pa, it is determined that the gas-fired water heater has not experienced deflagration. This preset air pressure rise can be set based on the fan operating status, duct structure, and air pressure fluctuation range during normal ignition of different gas-fired water heaters.

[0089] Another possible implementation involves determining that a deflagration has occurred in a gas-fired water heater when the combustion characteristic parameters during the ignition process do not conform to the preset combustion characteristic parameters, provided that the combustion characteristic parameters include the change in wind pressure per unit time. This includes comparing the change in wind pressure per unit time with the preset change in wind pressure per unit time; and determining that a deflagration has occurred in a gas-fired water heater when the change in wind pressure per unit time is greater than the preset change in wind pressure per unit time.

[0090] Specifically, in S201, based on the increase in wind pressure... and the duration of wind pressure rise Determine the change in wind pressure per unit time Change in wind pressure per unit time It reflects not only the magnitude of the wind pressure increase but also the time taken for that increase to occur. Ordinary adjustments to fan speed and changes in flue resistance can also cause some changes in wind pressure, but these changes are usually relatively continuous or slow. The pressure shock generated by deflagration is distinctly instantaneous; the wind pressure typically rises rapidly to its peak value within a short period. Therefore, the change in wind pressure per unit time corresponding to deflagration is usually significantly greater than the change in wind pressure per unit time during normal ignition.

[0091] For example, the preset wind pressure change per unit time can be set to 20. (The text abruptly ends here, seemingly mid-sentence.) If the value is greater than 20, it is determined that the change in wind pressure per unit time does not conform to the preset change in wind pressure per unit time, and the gas-fired water heater is judged to have experienced deflagration. By comprehensively characterizing the magnitude of wind pressure change and the time taken for this change to occur, the possibility of misjudging a slow increase in wind pressure as deflagration can be reduced.

[0092] Therefore, by obtaining only the characteristic parameters of sudden wind pressure changes, the magnitude of the pressure impact caused by deflagration can be detected based on the increase in wind pressure, or the instantaneous change of the pressure impact can be detected based on the change in wind pressure per unit time. Thus, the appropriate deflagration determination method can be selected according to the wind pressure detection conditions of the gas water heater.

[0093] Another possible implementation involves determining that a deflagration has occurred in the gas water heater when the combustion characteristic parameters, including the flame ionization signal mutation characteristic parameters, do not conform to the preset combustion characteristic parameters during the ignition process of the gas water heater. This includes: comparing the change in the first flame ionization signal with a preset change in the flame ionization signal, comparing the mutation duration of the flame ionization signal with a preset mutation duration, and comparing the recovery duration of the flame ionization signal with a preset recovery duration; and determining that a deflagration has occurred in the gas water heater when the change in the first flame ionization signal is greater than the preset change in the flame ionization signal, the mutation duration of the flame ionization signal is less than the preset mutation duration, and the recovery duration of the flame ionization signal is less than the preset recovery duration.

[0094] Specifically, the change in the first flame ion electrical signal The value used to characterize the flame ionization electrical signal detection value is determined by the first extreme value. Change to the second extreme value detection value The magnitude of change over time. After normal ignition and the establishment of a stable flame, the flame ionization signal detection value usually remains within the range corresponding to the stable flame. Even if there are slight fluctuations in the flame, its flame ionization signal detection value usually only changes within a small range. During deflagration, the instantaneous high temperature and airflow impact change the stable state of the flame, causing a significant abrupt change in the flame ionization signal detection value. Therefore, the first change in the flame ionization signal... The larger the value, the more significant the difference in the detected state of the flame before and after the impact.

[0095] Flame ion electrical signal change duration The value used to characterize the flame ionization electrical signal detection value is determined by the first extreme detection value. Change to the second extreme value detection value The time elapsed. Because the impact of deflagration is sudden, the flame state usually changes significantly in a short period of time. Therefore, compared with the slow fluctuation of ordinary flames, the duration of the sudden change in the flame ion electrical signal corresponding to deflagration is usually shorter.

[0096] Flame ion electrical signal recovery time The value used to characterize the flame ionization electrical signal detection value is determined by the second extreme value. Change to the third extreme value detection value The duration of the impact from deflagration is usually short. After the impact weakens, if the flame is not completely extinguished, the flame state will recover, and the flame ionization signal detection value will change in the direction corresponding to the stable combustion state. Therefore, the recovery time of the flame ionization signal can be used to reflect how quickly the flame recovers after being subjected to a momentary impact.

[0097] In other words, through the change in the first flame ion electrical signal The amplitude of the sudden change in the flame ion electrical signal can be determined by the duration of the sudden change. It can be determined whether the mutation occurred within a short period of time by recovering the duration of the flame ionization electrical signal. It can be determined whether the flame state recovers in a short period of time after the sudden change. When all three conditions are met, it indicates that the flame ion electrical signal has undergone a large-amplitude, rapid sudden change and rapid recovery process, which corresponds to the instantaneous impact of deflagration on the flame.

[0098] For example, the preset flame ion electrical signal change amount can be set to 50, the preset abrupt change duration can be set to 1 second, and the preset recovery duration can be set to 1 second. In the first flame ion electrical signal change amount... Greater than 50, duration of sudden change in flame ion electrical signal Less than 1 second, and the flame ionization electrical signal recovery time If the time is less than 1 second, it is determined that the characteristic parameters of the flame ion electrical signal change do not conform to the preset characteristic parameters of the flame ion electrical signal change, and it is determined that the gas water heater has deflagrated.

[0099] Furthermore, the change in the flame ion electrical signal per unit time during different stages of change can be used to determine whether a gas-fired water heater has experienced deflagration.

[0100] One possible implementation involves comparing the changes in the first, second, and third flame ionization electrical signals per unit time with corresponding preset changes in the flame ionization electrical signals per unit time, given that the combustion characteristic parameters include these three changes. If all three changes are greater than the corresponding preset changes in the flame ionization electrical signals per unit time, then the gas-fired water heater is determined to have experienced deflagration.

[0101] Specifically, the change in the first flame ion electrical signal per unit time Used to reflect the time from ignition moment To form the second extreme value detection value The overall rate of change of the flame ion electrical signal during the period; the change in the second flame ion electrical signal per unit time Used to reflect the flame ionization electrical signal from the first extreme detection value Change to the second extreme value detection value The mutation rate; the change in the third flame ion electrical signal per unit time Used to reflect the flame ionization electrical signal detected by the second extreme value To the third extreme value detection value The rate of change in recovery.

[0102] During normal ignition, the flame ionization electrical signal typically does not exhibit large changes per unit time across the aforementioned consecutive stages. However, during deflagration, due to the instantaneous impact on the flame, the overall change in the flame ionization electrical signal, the abrupt change during the impact, and the recovery after the impact can all exhibit rapid rates of change. Therefore, simultaneously judging the unit time change of the first flame ionization electrical signal is crucial. The change in the second flame ion electrical signal per unit time and the change in the third flame ion electrical signal per unit time It can verify the abrupt change process of flame ion electrical signal at different time stages, reducing misjudgments caused by single signal noise or ordinary flame oscillation.

[0103] For example, the unit-time variation of the first preset flame ionization electrical signal, the unit-time variation of the second preset flame ionization electrical signal, and the unit-time variation of the third preset flame ionization electrical signal can all be set to 30. The unit-time variation of the first flame ionization electrical signal... The change in the second flame ion electrical signal per unit time and the change in the third flame ion electrical signal per unit time If all values ​​are greater than 30, it is determined that the characteristic parameters of the flame ion electrical signal mutation do not conform to the preset characteristic parameters of the flame ion electrical signal mutation, and it is determined that the gas water heater has experienced deflagration.

[0104] The above-described implementation methods independently determine deflagration using either the wind pressure abrupt change characteristic parameter or the flame ionization electrical signal abrupt change characteristic parameter. In actual ignition, fluctuations in fan speed and changes in airflow within the flue can individually cause wind pressure anomalies, while ordinary flame oscillations or interference with the detection signal can also individually cause changes in the flame ionization electrical signal. Therefore, when both the wind pressure abrupt change characteristic parameter and the flame ionization electrical signal abrupt change characteristic parameter are obtained simultaneously, a joint judgment can be made by utilizing the temporal correlation between the two types of parameters.

[0105] Another possible implementation involves determining that a deflagration has occurred in a gas-fired water heater when the combustion characteristic parameters, including wind pressure surge characteristic parameters and flame ionization signal surge characteristic parameters, do not conform to preset combustion characteristic parameters during the ignition process. This includes: acquiring the moment when the wind pressure peak occurs after the gas-fired water heater ignites and the second moment corresponding to the second extreme value detected by the change in the flame ionization signal detection value; determining the time difference between the wind pressure surge and the flame ionization signal surge based on the wind pressure peak occurrence moment and the second moment; and determining that a deflagration has occurred in a gas-fired water heater when the wind pressure surge characteristic parameters do not conform to preset wind pressure surge characteristic parameters, the flame ionization signal surge characteristic parameters do not conform to preset flame ionization signal surge characteristic parameters, and the time difference is less than a preset synchronization time difference.

[0106] Specifically, based on the time of peak wind pressure occurrence Second extreme value detection value The corresponding second moment The absolute value of the difference between them determines the time difference of change. : .

[0107] Due to the duration of wind pressure increase At the time of ignition Starting from the first signal change duration Similarly, based on the ignition time Starting from this point, the aforementioned time difference of change can also be expressed as: .

[0108] During deflagration, the instantaneous and intense combustion of gas in the combustion chamber simultaneously generates a pressure surge and a change in flame state. Therefore, the peak wind pressure and the second extreme value of the flame ionization electrical signal, formed by the impact, typically occur within a short timeframe. If the time difference between these two changes is significant, the corresponding changes in wind pressure and flame ionization electrical signal may be caused by different factors. By setting a preset synchronization time difference, it is possible to further confirm whether the sudden changes in wind pressure and flame ionization electrical signal share the same abnormal combustion source.

[0109] For example, the preset synchronization time difference can be set to 2 seconds. This applies when the wind pressure change characteristic parameters do not conform to the preset wind pressure change characteristic parameters, the flame ionization electrical signal change characteristic parameters do not conform to the preset flame ionization electrical signal change characteristic parameters, and the change time difference... If the time is less than 2 seconds, it is determined that the gas-fired water heater has experienced a deflagration.

[0110] In the above joint judgment process, different specific combinations can be formed based on the different types of combustion characteristic parameters obtained in S201.

[0111] For example, in the first combination, the wind pressure increase can be used as a characteristic parameter for wind pressure change, and the change in the first flame ion electrical signal, the duration of the flame ion electrical signal change, and the recovery time of the flame ion electrical signal can be used as characteristic parameters for the flame ion electrical signal change. When the wind pressure increase is greater than a preset wind pressure increase, the change in the first flame ion electrical signal is greater than a preset flame ion electrical signal change, the duration of the flame ion electrical signal change is less than a preset change duration, the recovery time of the flame ion electrical signal is less than a preset recovery time, and the time difference between these changes is less than a preset synchronization time difference, it is determined that a deflagration has occurred in the gas-fired water heater.

[0112] For example, in the increase of wind pressure Greater than 50 Pa, change in the first flame ionization electrical signal Greater than 50, duration of sudden change in flame ion electrical signal Less than 1 second, flame ion electrical signal recovery time Less than 1 second, and the time difference of change If the time is less than 2 seconds, it is determined that the gas-fired water heater has experienced a deflagration.

[0113] In the second combination, the change in wind pressure per unit time can be used as the characteristic parameter for sudden wind pressure changes, and the changes in the first, second, and third flame ion electrical signals per unit time can be used as the characteristic parameters for sudden changes in flame ion electrical signals. When the change in wind pressure per unit time and the changes in the three flame ion electrical signals per unit time are all greater than their respective preset parameters, and the time difference between these changes is less than the preset synchronization time difference, it is determined that a deflagration has occurred in the gas-fired water heater.

[0114] For example, the change in wind pressure per unit time Greater than 20, the change in the first flame ionization electrical signal per unit time Greater than 30, the change in the second flame ion electrical signal per unit time Greater than 30, the change in the third flame ion electrical signal per unit time Greater than 30, and the time difference of change If the time is less than 2 seconds, it is determined that the gas-fired water heater has experienced a deflagration.

[0115] In addition, the increase in wind pressure can be combined with the unit-time changes in the three flame ionization electrical signals, or the unit-time change in wind pressure can be combined with the change in the first flame ionization electrical signal, the abrupt change duration of the flame ionization electrical signal, and the recovery duration of the flame ionization electrical signal. For both combinations, if the combustion characteristic parameters on the wind pressure side, the combustion characteristic parameters on the flame ionization electrical signal side, and the time difference between the two types of signals all fail to meet the corresponding requirements for normal combustion, then the gas-fired water heater is determined to have experienced deflagration.

[0116] By using the different judgment methods described above, deflagration can be quickly identified based on sudden changes in wind pressure or flame ionization signals when the equipment only has a single detection condition. Alternatively, when both types of detection conditions are available, deflagration can be comprehensively verified by sudden changes in pressure, sudden changes in flame state, and the time synchronization relationship between the two types of changes. This reduces misjudgments caused by ordinary wind pressure fluctuations, ordinary flame fluctuations, or interference from detection signals.

[0117] Furthermore, during actual ignition, there may be instances where the flame ionization electrical signal exhibits significant abrupt changes, but the degree of abnormality has not yet reached the level required to directly determine the conditions for deflagration. In such cases, the degree of abrupt change in the flame ionization electrical signal can be graded to identify deflagration risks during ignition in advance.

[0118] One possible approach is to determine the deflagration risk level of the gas-fired water heater during the ignition process based on the duration of the sudden change and recovery of the flame ionization signal. Alternatively, the deflagration risk level can be determined based on the unit-time changes in the second and third flame ionization signals.

[0119] Specifically, multiple level ranges can be set for both the duration of the flame ionization signal mutation and the duration of its recovery. A shorter mutation duration indicates a faster change in the flame ionization signal after being impacted; a shorter recovery duration indicates a faster recovery after the mutation. When both durations fall within the range corresponding to a higher risk level, a higher deflagration risk level can be determined.

[0120] Furthermore, multiple level ranges can be set for the unit-time changes of the second and third flame ion electrical signals. The larger the unit-time changes of the second and third flame ion electrical signals, the more violent the sudden change and recovery process of the flame ion electrical signals, and the higher the corresponding deflagration risk level.

[0121] For example, the deflagration risk level can be divided into five levels, with level three set as the risk warning level and level five set as the deflagration level. When the deflagration risk level reaches level three but not level five, it can be determined that the gas-fired water heater is currently in a deflagration risk state; when it reaches level five, deflagration determination and subsequent safety protection can be performed based on the corresponding combustion characteristic parameters.

[0122] When a gas-fired water heater is determined to be at risk of deflagration, the gas supply correction amount can be determined based on the deflagration risk level, and the gas supply amount for the next ignition of the water heater can be reduced accordingly. The gas supply amount can be adjusted by the proportional valve current, the gas valve opening, the gas supply duration during the ignition phase, or the corresponding gas supply control parameters.

[0123] During the next ignition, the flame ionization electrical signal detection data is reacquired, and the deflagration risk level is reassessed. If the reassessed deflagration risk level still reaches the risk warning level but not the deflagration level, the gas supply adjustment is updated based on the reassessed deflagration risk level, and the gas supply for subsequent ignitions continues to be reduced. If the reassessed deflagration risk level is lower than the risk warning level, the reduction of the gas supply for subsequent ignitions is stopped. Therefore, early intervention can be implemented in the subsequent ignition process when the flame ionization electrical signal shows obvious abnormalities but has not yet reached the direct deflagration determination criteria, reducing the possibility of further gas accumulation and deflagration.

[0124] Furthermore, upon determining that a deflagration has occurred in a gas-fired water heater, the current ignition process can be stopped, and the gas-fired water heater can be prohibited from continuing the secondary ignition process corresponding to this ignition. Specifically, the main valve can be closed to stop the continued supply of gas to the burner and generate a deflagration fault status or a deflagration lockout flag. Even if a demand for domestic hot water, heating, or other combustion is received again while the deflagration fault status remains unresolved, the gas-fired water heater can be prevented from re-igniting.

[0125] Simultaneously, it can generate deflagration alarm information. This deflagration alarm information can be output through the display interface of the gas water heater, fault codes, indicator lights, buzzers, or voice prompts. When the gas water heater has communication capabilities, it can also send deflagration alarm information to the user terminal or after-sales platform to prompt the user or after-sales personnel to promptly inspect and handle the gas water heater.

[0126] By stopping secondary ignition and implementing corresponding safety protection after a deflagration is detected, it is possible to avoid re-ignition before the combustion chamber has recovered or the cause of the abnormality has been eliminated, thereby reducing the risk of re-deflagration and improving the safety of the gas water heater during ignition and subsequent use.

[0127] The above primarily describes the solutions provided in the embodiments of this application from the perspective of the working principle of the equipment. It is understood that, in order to achieve the above functions, the gas-fired water heater includes corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, in conjunction with the algorithm steps of the examples described in the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0128] This application embodiment can divide the gas-fired water heater into functional modules according to the above method example. For example, each function can be divided into a separate functional module, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware or as a software functional module.

[0129] It should be noted that the module division in this embodiment is illustrative and represents only one logical functional division; in actual implementation, other division methods may be used. When dividing functional modules according to their respective functions, Figure 3 A schematic diagram of a possible composition of the deflagration detection device for the gas-fired water heater involved in the above and embodiment examples is shown. Figure 3 As shown, the deflagration detection device 300 of the gas-fired water heater may include: an acquisition module 301 and a determination module 302.

[0130] The acquisition module 301 is used to support the execution of the deflagration detection device 300 of the gas-fired water heater. Figure 2 S201 in the schematic method for detecting deflagration in gas-fired water heaters.

[0131] The judgment module 302 is used to support the execution of the deflagration detection device 300 of the gas-fired water heater. Figure 2 S202 in the schematic method for detecting deflagration in gas-fired water heaters.

[0132] One possible implementation is that the combustion characteristic parameters include wind pressure change characteristic parameters, which include the wind pressure increase. The acquisition module, when acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater, specifically acquires the steady-state wind pressure value before ignition and the peak wind pressure value after ignition. The wind pressure increase is determined based on the difference between the steady-state wind pressure value and the peak wind pressure value.

[0133] One possible implementation involves a determination module that, when the combustion characteristic parameters during the ignition process of a gas-fired water heater do not conform to preset combustion characteristic parameters, determines that a deflagration has occurred in the gas-fired water heater. Specifically, this module compares the increase in air pressure with a preset increase in air pressure. If the increase in air pressure is determined to be greater than the preset increase in air pressure, a deflagration is determined to have occurred in the gas-fired water heater.

[0134] One possible implementation is that the wind pressure change characteristic parameter also includes the wind pressure change per unit time. The acquisition module, when acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater, specifically acquires: the ignition time of the gas-fired water heater and the peak occurrence time corresponding to the peak wind pressure. Based on the peak occurrence time and the ignition time of the gas-fired water heater, the duration of the wind pressure rise is determined. Based on the wind pressure rise amount and the wind pressure rise duration, the wind pressure change per unit time is determined.

[0135] One possible implementation involves a determination module that, when the combustion characteristic parameters during the ignition process of a gas-fired water heater do not conform to preset combustion characteristic parameters, determines that a deflagration has occurred in the gas-fired water heater. Specifically, this involves comparing the change in air pressure per unit time with a preset change in air pressure per unit time. If the change in air pressure per unit time is greater than the preset change in air pressure per unit time, then a deflagration is determined to have occurred in the gas-fired water heater.

[0136] One possible implementation involves combustion characteristic parameters including flame ionization signal abrupt change characteristic parameters, which include a first flame ionization signal change amount, a flame ionization signal rebound duration, and a flame ionization signal recovery duration. The acquisition module, when acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater, specifically performs the following steps: acquiring flame ionization signal detection data during the ignition process of the gas-fired water heater; determining, based on the flame ionization signal detection data, a first extreme detection value formed by the flame ionization signal detection value after flame detection, and a first time point corresponding to the first extreme detection value; determining, based on the flame ionization signal detection data, a second extreme detection value formed by the change in the flame ionization signal detection value after the first extreme detection value, and a second time point corresponding to the second extreme detection value; determining, based on the flame ionization signal detection data, a third extreme detection value formed by the change in the flame ionization signal detection value after the second extreme detection value, and a third time point corresponding to the third extreme detection value; determining the first flame ionization signal change amount based on the difference between the first and second extreme detection values; and determining the flame ionization signal abrupt change duration based on the first and second time points. The recovery time of the flame ion electrical signal is determined based on the second and third time points.

[0137] One possible implementation involves a determination module that, when the combustion characteristic parameters during the ignition process of a gas-fired water heater do not conform to preset combustion characteristic parameters, determines that a deflagration has occurred in the gas-fired water heater. Specifically, this module compares the change in the first flame ion electrical signal with a preset change in the flame ion electrical signal, compares the duration of the flame ion electrical signal abrupt change with a preset abrupt change duration, and compares the recovery time of the flame ion electrical signal with a preset recovery time. If it is determined that the change in the first flame ion electrical signal is greater than the preset change in the flame ion electrical signal, the duration of the flame ion electrical signal abrupt change is less than the preset abrupt change duration, and the recovery time of the flame ion electrical signal is less than the preset recovery time, then a deflagration is determined to have occurred in the gas-fired water heater.

[0138] One possible implementation is that the flame ionization electrical signal abrupt change characteristic parameters further include the first flame ionization electrical signal unit-time change, the second flame ionization electrical signal unit-time change, and the third flame ionization electrical signal unit-time change. The acquisition module, when acquiring combustion characteristic parameters during the ignition process of the gas-fired water heater, specifically performs the following: acquiring the ignition time of the gas-fired water heater; determining the duration of the first signal change based on the second time and the ignition time; determining the unit-time change of the first flame ionization electrical signal based on the flame ionization electrical signal change and the first signal change duration; determining the unit-time change of the second flame ionization electrical signal based on the flame ionization electrical signal change and the flame ionization electrical signal abrupt change duration; determining the second flame ionization electrical signal change based on the difference between the second extreme value detection value and the third extreme value detection value; and determining the unit-time change of the third flame ionization electrical signal based on the second flame ionization electrical signal change and the flame ionization electrical signal recovery time.

[0139] One possible implementation involves a determination module that, when the combustion characteristic parameters during the ignition process of a gas-fired water heater do not conform to preset combustion characteristic parameters, determines that deflagration has occurred in the gas-fired water heater. Specifically, this involves comparing the unit-time changes of the first, second, and third flame ion electrical signals with their corresponding preset unit-time changes. If all three unit-time changes are greater than their respective preset unit-time changes, deflagration is determined to have occurred in the gas-fired water heater.

[0140] One possible implementation involves combustion characteristic parameters including wind pressure surge characteristic parameters and flame ionization electrical signal surge characteristic parameters. The determination module, used to determine if deflagration has occurred in the gas-fired water heater when the combustion characteristic parameters during the ignition process do not conform to preset combustion characteristic parameters, specifically involves: acquiring the moment when the wind pressure peak occurs after ignition and the second moment corresponding to the second extreme value detected by the change in the flame ionization electrical signal detection value. Based on the moment of the wind pressure peak occurrence and the second moment, the time difference between the wind pressure surge and the flame ionization electrical signal surge is determined. If the wind pressure surge characteristic parameters do not conform to preset wind pressure surge characteristic parameters, the flame ionization electrical signal surge characteristic parameters do not conform to preset flame ionization electrical signal surge characteristic parameters, and the time difference is less than a preset synchronization time difference, deflagration is determined to have occurred in the gas-fired water heater.

[0141] One possible implementation involves an acquisition module that, when acquiring the steady-state air pressure value before ignition of the gas-fired water heater, specifically controls the gas-fired water heater's fan to operate at a preset ignition speed. Once it is determined that the fan operation meets stable conditions, the module acquires the steady-state air pressure value before ignition and controls the gas-fired water heater to ignite.

[0142] It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.

[0143] The deflagration detection device 300 for gas-fired water heaters provided in this application embodiment is used to perform the above-mentioned functions. Figure 2 The deflagration detection method for gas-fired water heaters shown can achieve the same effect as the deflagration detection method for gas-fired water heaters described above.

[0144] This application also provides a gas-fired water heater, including a processor and a memory. The memory stores machine-executable instructions that can be executed by the processor. The processor executes the machine-executable instructions to implement the above-mentioned deflagration detection method for the gas-fired water heater.

[0145] This application also provides a deflagration detection system 400 for a gas-fired water heater, such as... Figure 4 As shown, the deflagration detection system 400 of the gas-fired water heater includes at least one processor 401 and at least one interface circuit 402.

[0146] As an example, when the deflagration detection system 400 of the gas-fired water heater includes a processor and an interface circuit, the processor can be... Figure 4 The processor 401 shown in the solid box (or the processor 401 shown in the dashed box) can be an interface circuit. Figure 4 The interface circuit 402 is shown in the solid box (or the dashed box). When the deflagration detection system 400 of the gas-fired water heater includes two processors and two interface circuits, then the two processors include... Figure 4 The processor 401 shown in the solid box and the processor 401 shown in the dashed box, these two interface circuits include Figure 4 Interface circuit 402 is shown in both solid and dashed boxes. No limitations are imposed on this.

[0147] Processor 401 and interface circuit 402 can be interconnected via a line. For example, interface circuit 402 can be used to receive signals. Alternatively, interface circuit 402 can be used to send signals to other devices (e.g., processor 401). For instance, interface circuit 402 can read computer instructions stored in memory and send those instructions to processor 401. Processor 401 executes the instructions and, in conjunction with input / output devices, implements the various steps in the above embodiments, such as implementing... Figure 2 The steps performed in the illustrated method embodiment are shown. Of course, the deflagration detection system for this gas-fired water heater may also include other discrete components, and this application embodiment does not specifically limit this.

[0148] Through the above description of the embodiments, those skilled in the art can clearly understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0149] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0150] The units described as separate components may or may not be physically separate. A component shown as a unit can be one or more physical units; that is, it can be located in one place or distributed in multiple different locations. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0151] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0152] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of the embodiments of this application, in essence, or the part that contributes, or all or part of the technical solution, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0153] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A deflagration detection method for a gas water heating apparatus, characterized by, The method includes: In response to the start command of the gas water heater, the combustion characteristic parameters during the ignition process of the gas water heater are acquired, wherein the combustion characteristic parameters include wind pressure change characteristic parameters and / or flame ion electrical signal change characteristic parameters. If the combustion characteristic parameters during the ignition process of a gas-fired water heater do not conform to the preset combustion characteristic parameters, it is determined that the gas-fired water heater has experienced deflagration.

2. The method of claim 1, wherein, The combustion characteristic parameters include the wind pressure change characteristic parameters, which include the wind pressure increase; acquiring the combustion characteristic parameters during the ignition process of the gas-fired water heater includes: Obtain the steady-state wind pressure value before ignition and the peak wind pressure value after ignition of the gas-fired water heater; The wind pressure increase is determined based on the difference between the steady-state wind pressure value and the peak wind pressure value.

3. The method of claim 2, wherein, When the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to the preset combustion characteristic parameters, it is determined that the gas-fired water heater has experienced deflagration, including: Compare the wind pressure increase with the preset wind pressure increase; If the increase in air pressure is determined to be greater than the preset increase in air pressure, it is determined that the gas-fired water heater has experienced a deflagration.

4. The method of claim 2, wherein, The wind pressure change characteristic parameter also includes the wind pressure change per unit time; the acquisition of combustion characteristic parameters during the ignition process of the gas-fired water heater includes: Obtain the ignition time of the gas-fired water heater and the peak occurrence time corresponding to the peak wind pressure; The duration of the wind pressure rise is determined based on the time of the peak occurrence and the ignition time of the gas-fired water heater. The change in wind pressure per unit time is determined based on the amount of wind pressure increase and the duration of the wind pressure increase.

5. The method of claim 4, wherein, When the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to the preset combustion characteristic parameters, it is determined that the gas-fired water heater has experienced deflagration, including: The change in wind pressure per unit time is compared with the preset change in wind pressure per unit time; If the change in wind pressure per unit time is greater than the preset change in wind pressure per unit time, it is determined that the gas-fired water heater has experienced a deflagration.

6. The method of claim 1, wherein, The combustion characteristic parameters include the flame ion electrical signal abrupt change characteristic parameters, which include the first flame ion electrical signal change amount, the flame ion electrical signal rebound time, and the flame ion electrical signal recovery time; acquiring the combustion characteristic parameters during the ignition process of the gas-fired water heater includes: Acquire flame ion electrical signal detection data during the ignition process of the gas-fired water heater; Based on the flame ion electrical signal detection data, determine the first extreme value of the flame ion electrical signal detection value after the flame is detected, and the first time corresponding to the first extreme value of the detection value; Based on the flame ion electrical signal detection data, after determining the first extreme value detection value, the second extreme value detection value formed by the change of the flame ion electrical signal detection value, and the second time corresponding to the second extreme value detection value; Based on the flame ion electrical signal detection data, after determining the second extreme value detection value, the third extreme value detection value is formed by the change of the flame ion electrical signal detection value, and the third time point corresponding to the third extreme value detection value is determined; The change in the first flame ion electrical signal is determined based on the difference between the first extreme value detection value and the second extreme value detection value. The duration of the sudden change in the flame ion electrical signal is determined based on the first time point and the second time point; The recovery time of the flame ion electrical signal is determined based on the second time point and the third time point.

7. The method of claim 6, wherein, When the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to the preset combustion characteristic parameters, it is determined that the gas-fired water heater has experienced deflagration, including: The change in the first flame ion electrical signal is compared with the preset change in the flame ion electrical signal, the abrupt change duration of the flame ion electrical signal is compared with the preset abrupt change duration, and the recovery duration of the flame ion electrical signal is compared with the preset recovery duration. If the change in the first flame ion electrical signal is greater than the preset change in the flame ion electrical signal, the abrupt change in the flame ion electrical signal is less than the preset abrupt change time, and the recovery time of the flame ion electrical signal is less than the preset recovery time, then the gas-fired water heater is determined to have experienced a deflagration.

8. The method of claim 6, wherein, The flame ion electrical signal abrupt change characteristic parameters further include the first flame ion electrical signal unit time change, the second flame ion electrical signal unit time change, and the third flame ion electrical signal unit time change; the acquisition of combustion characteristic parameters during the ignition process of the gas-fired water heater includes: Obtain the ignition time of the gas-fired water heater; The duration of the first signal change is determined based on the second time point and the ignition time point; The change in the first flame ion electrical signal per unit time is determined based on the change amount of the first flame ion electrical signal and the duration of the first signal change. The change in the second flame ion electrical signal per unit time is determined based on the change in the first flame ion electrical signal and the duration of the sudden change in the flame ion electrical signal. The change in the second flame ion electrical signal is determined based on the difference between the second extreme value detection value and the third extreme value detection value. The change in the third flame ion electrical signal per unit time is determined based on the change in the second flame ion electrical signal and the recovery time of the flame ion electrical signal.

9. The method according to claim 8, characterized in that, When the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to the preset combustion characteristic parameters, it is determined that the gas-fired water heater has experienced deflagration, including: The unit time change of the first flame ion electrical signal, the unit time change of the second flame ion electrical signal, and the unit time change of the third flame ion electrical signal are compared with the corresponding preset unit time change of the flame ion electrical signal. If the unit time change of the first flame ion electrical signal, the unit time change of the second flame ion electrical signal, and the unit time change of the third flame ion electrical signal are all greater than the corresponding preset unit time change of the flame ion electrical signal, it is determined that the gas water heater has experienced deflagration.

10. The method according to claim 1, characterized in that, The combustion characteristic parameters include the wind pressure change characteristic parameters and the flame ionization signal change characteristic parameters; when the combustion characteristic parameters during the ignition process of the gas-fired water heater do not conform to the preset combustion characteristic parameters, it is determined that the gas-fired water heater has experienced deflagration, including: The peak wind pressure after the gas water heater is ignited is obtained at the time when the peak wind pressure occurs and the second time corresponding to the second extreme value formed by the change of the flame ion electrical signal detection value. Based on the time of occurrence of the wind pressure peak and the second time, determine the time difference between the sudden change in wind pressure and the sudden change in flame ion electrical signal; If the wind pressure change characteristic parameter does not conform to the preset wind pressure change characteristic parameter, the flame ion electrical signal change characteristic parameter does not conform to the preset flame ion electrical signal change characteristic parameter, and the change time difference is less than the preset synchronization time difference, it is determined that the gas water heater has deflagrated.

11. The method according to claim 2, characterized in that, The step of obtaining the steady-state value of the air pressure before ignition of the gas-fired water heater includes: The fan of the gas-fired water heater is controlled to run at a preset ignition speed. If the fan operation meets the stable conditions, the steady-state value of the air pressure before the gas water heater is ignited is obtained, and the gas water heater is controlled to ignite.

12. A deflagration detection device for a gas-fired hot water equipment, characterized in that, The device includes: The acquisition module is used to acquire combustion characteristic parameters during the ignition process of the gas water heater in response to the start command of the gas water heater, wherein the combustion characteristic parameters include wind pressure change characteristic parameters and / or flame ion electrical signal change characteristic parameters. The determination module is used to determine that the gas water heater has deflagration when the combustion characteristic parameters during the ignition process of the gas water heater do not meet the preset combustion characteristic parameters.

13. A gas-fired hot water device, characterized in that, The device includes a processor and a memory, the memory storing machine-executable instructions that can be executed by the processor, the processor executing the machine-executable instructions to implement the deflagration detection method for a gas-fired water heater as described in any one of claims 1 to 11.

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