Control method of gas water heater, gas water heater and storage medium

Abstract

The invention discloses a control method of a gas water heater, the gas water heater and a storage medium, and relates to the technical field of heat generation devices, the control method of the gas water heater comprises the steps that the voltage deviation between the current thermal voltage and the reference thermal voltage of a thermocouple is obtained; based on a preset first mapping relation between the voltage deviation and the rotating speed adjustment amount, the target rotating speed adjustment amount corresponding to the voltage deviation is determined, and the sum of the target rotating speed adjustment amount and the current rotating speed of the draught fan is within the wind speed limit value; and the fan rotating speed of the gas water heater is adjusted according to the target rotating speed adjusting amount. The voltage deviation between the current thermal voltage of the fan and the reference thermal voltage is determined, the target rotating speed adjustment amount is determined according to the mapping relation between the rotating speed and the voltage deviation, and the rotating speed of the fan of the gas water heater is adjusted based on the target rotating speed adjustment amount, so that the thermal voltage after rotating speed adjustment is stabilized within the allowable fluctuation range of the reference thermal voltage. And the combustion utilization rate of gas is improved.

Description

Technical Field

[0001] This application relates to the field of heat generation device technology, and in particular to a control method for a gas water heater, a gas water heater and a storage medium. Background Technology

[0002] Gas water heaters adjust gas combustion by detecting changes in the calorific value of the gas source. During the gas source calorific value detection process, the ratio of the actual hot water output to the benchmark hot water output is calculated, and this ratio is used to determine whether the gas source calorific value has fluctuated.

[0003] However, under complex operating conditions such as different flue lengths, burner blockages, or different gas compositions, the hot water output rate itself varies very little. The ratio of the actual hot water output rate to the benchmark hot water output rate is difficult to truly reflect the fluctuation of the gas source calorific value, resulting in low gas combustion stability.

[0004] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main objective of this application is to provide a control method for a gas water heater, a gas water heater, and a storage medium, aiming to solve the technical problem of low gas combustion stability in gas water heaters under complex operating conditions.

[0006] To achieve the above objectives, this application proposes a control method for a gas water heater, the method comprising: Obtain the voltage deviation between the current thermocouple voltage and the reference thermocouple voltage; Based on the preset first mapping relationship between the voltage deviation and the speed adjustment amount, the target speed adjustment amount corresponding to the voltage deviation is determined, and the sum of the target speed adjustment amount and the current speed of the fan is within the wind speed limit value. Adjust the fan speed of the gas water heater according to the target speed adjustment amount.

[0007] In one embodiment, the step of determining the target speed adjustment amount corresponding to the voltage deviation based on a preset first mapping relationship between the voltage deviation and the speed adjustment amount includes: If the voltage deviation is greater than the first threshold, the target speed adjustment amount is determined to be positive. If the voltage deviation is less than the second threshold, the target speed adjustment amount is determined to be negative; If the voltage deviation is greater than or equal to the second threshold and less than or equal to the first threshold, the target speed adjustment is determined to be zero. Among them, the first threshold is greater than the second threshold, the first threshold is greater than the normal deviation value, and the second threshold is less than the normal deviation value.

[0008] In one embodiment, the step of determining that the target speed adjustment amount is positive if the voltage deviation is greater than a first threshold includes: If the voltage deviation is greater than the first threshold and less than the third threshold, the target speed adjustment amount is determined to be the first adjustment amount. If the voltage deviation is greater than the third threshold, the target speed adjustment amount is determined to be the second adjustment amount. The third threshold is greater than the first threshold, the second adjustment amount is greater than the first adjustment amount, and both the first adjustment amount and the second adjustment amount are positive values.

[0009] In one embodiment, the step of determining that the target speed adjustment amount is negative if the voltage deviation is less than a second threshold includes: If the voltage deviation is greater than the fourth threshold and less than the second threshold, the target speed adjustment amount is determined to be the third adjustment amount; If the voltage deviation is less than the fourth threshold, the target speed adjustment amount is determined to be the fourth adjustment amount. The fourth threshold is less than the second threshold, the fourth adjustment amount is less than the third adjustment amount, and both the third and fourth adjustment amounts are negative.

[0010] In one embodiment, before adjusting the fan speed of the gas water heater according to the target speed adjustment amount, the control method of the gas water heater further includes: Obtain the current deviation between the current current of the fan and the reference current; If the current deviation is detected to meet the preset current deviation threshold, the step of adjusting the fan speed of the gas water heater according to the target speed adjustment amount is executed.

[0011] In one embodiment, the control method for the gas water heater further includes: If the current deviation is detected to be inconsistent with the preset current deviation threshold, the gas water heater is turned off.

[0012] In one embodiment, the step of determining the reference thermal voltage includes: Obtain the current gas volume of the gas water heater; The reference thermal voltage is determined based on a pre-configured second mapping relationship between the gas quantity and the reference thermal voltage.

[0013] In one embodiment, after the step of adjusting the fan speed of the gas water heater according to the target speed adjustment amount, the control method of the gas water heater further includes: Obtain the target rotational speed of the fan; Based on the target rotational speed, the second mapping relationship between the gas volume and the fan speed is updated.

[0014] In addition, to achieve the above objectives, this application also proposes a gas water heater, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the control method for the gas water heater as described above.

[0015] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the control method for a gas water heater as described above.

[0016] One or more technical solutions proposed in this application have at least the following technical effects: When the gas water heater is running, the voltage deviation between the current thermocouple voltage and the reference thermocouple voltage is determined. Then, by mapping the voltage deviation to the speed adjustment, the target speed adjustment corresponding to the voltage deviation is determined. Finally, the fan operation is controlled based on the target speed adjustment, thereby optimizing the gas-air mixing ratio from the perspective of fan operation status regulation, correcting the fan speed, ensuring stable gas combustion, improving the combustion stability of the gas water heater under complex operating conditions, and ensuring the reliability and continuity of the gas water heater operation, avoiding energy waste or equipment failure caused by unstable combustion. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A flowchart illustrating the first embodiment of the control method for a gas water heater according to this application; Figure 2 This is a mapping diagram of the fan speed and reference current in the control method of the gas water heater of this application; Figure 3 This is a mapping diagram of the preset proportional valve and the reference thermal voltage in the control method of the gas water heater of this application; Figure 4 This is a mapping diagram of the preset proportional valve and fan speed in the control method of the gas water heater of this application; Figure 5A simplified flowchart illustrating the control method for a gas water heater provided in the second embodiment of this application; Figure 6 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the control method of the gas water heater in the embodiments of this application.

[0020] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0022] Gas water heaters adjust gas combustion by detecting changes in the calorific value of the gas source. During the gas source calorific value detection process, the ratio of the actual hot water output to the benchmark hot water output is calculated, and this ratio is used to determine whether the gas source calorific value has fluctuated.

[0023] However, under complex operating conditions such as different flue lengths and burner blockages, the hot water output rate itself changes very little. The ratio of the actual hot water output rate to the benchmark hot water output rate is difficult to truly reflect the fluctuation of the gas source calorific value, resulting in low gas combustion stability.

[0024] Based on this, this application provides a solution that, during the operation of a gas water heater, determines the voltage deviation between the current thermocouple voltage and the reference thermocouple voltage. Then, through the mapping relationship between the speed adjustment and the voltage deviation, it determines the target speed adjustment corresponding to the voltage deviation. Finally, it controls the fan operation based on the target speed adjustment, thereby optimizing the gas-air mixing ratio from the perspective of fan operation status regulation, correcting the fan speed, ensuring stable gas combustion, improving the combustion stability of the gas water heater under complex operating conditions, and ensuring the reliability and continuity of the gas water heater's operation, avoiding energy waste or equipment failure caused by unstable combustion. Based on this, the gas water heater can continuously detect changes in thermocouple voltage and achieve closed-loop iterative control through repeated fine-tuning of the fan speed. This eliminates the need for frequent adjustments to the gas proportional valve opening, avoiding the risk of flame fluctuations or flameout, and maintaining high efficiency and safety in combustion even under complex operating conditions such as gas pressure fluctuations and external wind interference.

[0025] In this embodiment, the gas water heater is a low-emission constant-speed gas water heater. The water heater ensures stable airflow by operating the fan at a constant speed, thereby ensuring the stability of the air-fuel ratio. This ensures stable combustion while effectively avoiding water temperature fluctuations and meeting the demand for constant-temperature water use.

[0026] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific embodiments.

[0027] This application provides a control method for a gas water heater, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the control method for a gas water heater according to this application.

[0028] In this embodiment, the control method for the gas water heater includes steps S10 to S30: Step S10: Obtain the voltage deviation between the current thermocouple voltage and the reference thermocouple voltage.

[0029] In this embodiment, the current thermal voltage is the thermocouple thermal voltage detected during equipment operation, which is strongly correlated with parameters such as fan speed, load, and gas duct resistance. The reference thermal voltage refers to the standard voltage parameter of the gas water heater during the current gas flow PWM operation.

[0030] To eliminate interference from abnormal operating conditions such as fan blockage on the thermoelectric voltage detection results, the voltage deviation between the current thermoelectric voltage and the reference thermoelectric voltage is calculated only when the fan inlet and outlet channels are unobstructed, there is no significant abnormal air resistance, and the airflow is smooth. Therefore, during the operation of the gas water heater, sensors can collect the operating parameters of the gas water heater in real time, including the current thermoelectric voltage of the thermocouple, air pressure, current, and fan speed. One or more of these parameters can be used to determine whether the fan is in a normal ventilation state. For example, the fan pressure can be detected to determine if the fan is in a normal ventilation state, or the magnitude and changes in the current of the gas water heater can be detected to determine if the fan is in a normal ventilation state. The current thermoelectric voltage can be derived from the temperature collected by the thermocouple flame temperature detection unit, or it can be based on the voltage sampling circuit connected to both ends of the motor windings to collect thermoelectric voltage data in real time.

[0031] Voltage deviation, representing the difference between the current thermocouple voltage and the reference thermocouple voltage, can be a ratio (e.g., the ratio of the current thermocouple voltage to the reference thermocouple voltage), a difference (e.g., the difference between the current thermocouple voltage and the reference thermocouple voltage), or the difference between the two and the ratio of the reference thermocouple voltage. Different deviations correspond to different deviation thresholds or deviation ranges. Taking the ratio as an example, after obtaining the current thermocouple voltage and the reference thermocouple voltage, the ratio between the current thermocouple voltage and the reference thermocouple voltage can be calculated, and this ratio can be set as the voltage deviation. For example, if the temperature collected by the thermocouple is 100℃, the current thermocouple voltage is converted to 0.36V, and the pre-stored reference thermocouple voltage is 0.26V, the calculated ratio is approximately 1.4.

[0032] Step S20: Based on the preset mapping relationship between voltage deviation and speed adjustment amount, determine the target speed adjustment amount corresponding to the voltage deviation.

[0033] In this embodiment, a pre-defined mapping relationship is established between the voltage deviation and the fan speed adjustment. This mapping relationship can include functions, curves, lookup table values, etc. Therefore, the corresponding target speed adjustment can be determined by looking up tables, substituting data into formulas, or parameter conversion. The sum of the target speed adjustment and the current fan speed is within the wind speed limit, ensuring that after the fan speed adjustment, the target speed is within the range where the fan operates stably, avoiding risks caused by excessively high or low speeds.

[0034] The voltage deviation is the ratio between the current thermal voltage and the reference thermal voltage. When determining the target speed adjustment based on the voltage ratio and a lookup table, the deviation range of the voltage deviation can be determined first. Then, the speed adjustment value associated with the deviation range in the mapping relationship can be determined as the target speed adjustment. For example, if the voltage deviation is 1.1, the corresponding deviation range is [1.1-1.2]. By looking up the table, the speed adjustment for this range is determined to be 30 r / min, i.e., the target speed adjustment is 30 r / min. The deviation range is the range of thermal voltage ratios corresponding to the stable operation of the fan, calibrated through numerous experiments.

[0035] Understandably, when calculating based on the deviation range, to avoid unnecessary speed adjustments triggered by minor ratio fluctuations under normal operating conditions, a target speed adjustment value of 0 indicates that the voltage deviation is within the normal range. When the voltage deviation exceeds the normal range, the deviation range it falls within, and the corresponding target speed for that deviation range, are determined.

[0036] It should be noted that in this embodiment, the gas water heater is a low-emission constant-speed gas water heater. Its initial constant-speed parameter is calibrated to precisely match the oxygen content required for the optimal air-fuel ratio, thus ensuring basic low-emission combustion conditions. Under conditions where there is no airflow blockage, the current speed of this gas water heater typically corresponds to the speed at which the oxygen content required for the optimal air-fuel ratio is present. When the thermocouple temperature rises, i.e., the current thermal voltage increases, it indicates that the current oxygen content has not reached its optimal level. Insufficient air supply prevents complete fuel combustion, and the incompletely burned fuel forms a localized rich-fuel zone, causing the thermocouple hot-end temperature to rise. At this point, it is necessary to increase the fan speed to increase the air input into the combustion chamber, increase the oxygen concentration, and allow the air-fuel ratio to return to the optimal range. In other words, the combustion system characteristics of low-emission products dictate that the higher the fan speed, the more abundant the amount of air participating in combustion, and the more complete the fuel combustion. The flame transitions from a locally high-temperature rich-fuel state to a stable and uniform complete combustion state. Simultaneously, excess air absorbs some of the combustion heat, thus achieving the control effect of "the more fan, the lower the thermocouple hot-end temperature," thereby ensuring that the hot-end temperature returns to the standard value. Similarly, when the current thermal voltage drops, excess air will accelerate the flow rate of flue gas in the combustion chamber, and the residence time of high-temperature flue gas near the hot junction of the thermocouple will be greatly shortened. Heat cannot be effectively accumulated on the surface of the hot junction, further lowering the temperature of the hot junction. At this time, it is necessary to reduce the speed of the fan to reduce the oxygen content.

[0037] Therefore, when the deviation range of the voltage ratio between the current thermal voltage and the reference thermal voltage is greater than the normal range, the target speed adjustment is positive, and vice versa.

[0038] Optionally, besides determining the target speed adjustment amount through the ratio of voltages, the target speed adjustment amount can also be determined by calculating the difference between the current thermal voltage and the reference thermal voltage of the fan. That is, after collecting the current thermal voltage, the difference between the current thermal voltage and the reference thermal voltage is calculated. If the difference is positive, it indicates that the current thermal voltage is higher than the reference thermal voltage, meaning the current air intake is low, oxygen deficiency leads to localized rich combustion of the gas, causing the temperature to rise. In this case, based on the linear coefficient between the thermal voltage difference calibrated before the equipment leaves the factory and the speed adjustment amount, for example, every 0.01V difference corresponds to a speed adjustment amount of 10r / min. When the difference is 0.1V, the target speed adjustment amount of 100r / min is calculated according to the coefficient.

[0039] Step S30: Adjust the fan speed of the gas water heater according to the target speed adjustment amount.

[0040] After obtaining the target speed adjustment amount, if the target speed adjustment amount is positive, the fan speed is increased based on this adjustment amount; if it is negative, the fan speed is decreased, so that the thermocouple voltage of the equipment after speed adjustment approaches the reference thermocouple voltage. When the target speed adjustment amount is 0, no speed adjustment is required.

[0041] In this embodiment, when the length of the flue pipe of the gas water heater is not uniform, the thermocouple voltage changes with the wind pressure of the flue pipe. By measuring the voltage deviation between the thermocouple voltage and the reference thermocouple voltage, the oxygen content can be accurately determined and the fan speed can be adjusted to improve wind resistance.

[0042] Furthermore, when the fan speed of a gas water heater changes, the current thermal voltage and current values ​​will change in real time. Therefore, after adjusting the fan speed, the gas water heater will calculate the voltage deviation between the thermal voltage and the reference thermal voltage in real time, and adjust the actual fan speed when the target speed determined based on the voltage deviation is not equal to the current speed.

[0043] This embodiment provides a control method for a gas water heater. When the gas water heater is in operation, the voltage deviation between the thermal voltage and the reference thermal voltage is calculated. The target speed adjustment amount is determined through the voltage deviation and mapping relationship. Finally, the fan speed is adjusted based on the target speed adjustment amount. This allows for precise matching of the required fan speed when the thermal voltage of the gas water heater is unstable under complex operating conditions. It optimizes the mixing ratio of gas and air, significantly improves the combustion stability of the gas water heater under complex operating conditions, ensures the reliability of equipment operation and energy utilization efficiency, and reduces the risk of energy waste and equipment failure caused by unstable combustion.

[0044] Based on the first embodiment of this application, in the second embodiment of this application, the content that is the same as or similar to that in the first embodiment can be referred to the above description, and will not be repeated hereafter. In addition, step S20 further includes step S21: Step S21: If the voltage deviation is greater than the first threshold, determine that the target speed adjustment amount is positive.

[0045] In this embodiment, in addition to determining the target speed adjustment amount by the range of the voltage deviation, the speed adjustment amount can also be determined by the relationship between the voltage deviation and a preset threshold. The first threshold is greater than the normal deviation value of the voltage deviation.

[0046] Taking the ratio as an example, the normal deviation value of the voltage deviation is 0.95-1.05, and the first threshold is greater than 1.05. Therefore, when the voltage deviation is greater than the first threshold, the target speed adjustment is determined to be a positive value so as to reduce the temperature of the thermocouple by increasing the fan speed.

[0047] Furthermore, in the scenario of low-emission constant-speed gas water heaters, different voltage deviations have varying degrees of disturbance to the fan speed. The larger the deviation, the higher the amplitude and risk of speed fluctuations, and the more significant the impact of air-fuel ratio imbalance. For example, extreme deviations may directly lead to combustion instability and excessive emissions. Therefore, when the voltage deviation exceeds the first threshold, it is necessary to determine the target speed adjustment amount based on the specific degree of voltage deviation.

[0048] Specifically, if the voltage deviation is greater than the first threshold and less than the third threshold, the target speed adjustment amount is determined as the first adjustment amount; if the voltage deviation is greater than the third threshold, the target speed adjustment amount is determined as the second adjustment amount, and so on. A fifth threshold, a sixth threshold, and the corresponding adjustment amounts under these thresholds can also be set. The third threshold is greater than the first threshold, the second adjustment amount is greater than the first adjustment amount, and both the first and second adjustment amounts are positive values.

[0049] Similarly, if the voltage deviation is greater than the fourth threshold and less than the second threshold, the target speed adjustment amount is determined as the third adjustment amount; if the voltage deviation is less than the fourth threshold, the target speed adjustment amount is determined as the fourth adjustment amount. Here, the fourth threshold is less than the second threshold, the fourth adjustment amount is less than the second adjustment amount, and both the second and fourth adjustment amounts are negative values.

[0050] For example, the normal deviation is 0.95-1.05, the first threshold is 1.05, the third threshold is 1.10, the Nth threshold is 1.X, and X is (N+1). 0.025, where N is an odd number and greater than zero. When the voltage deviation is greater than 1.05 and less than 1.10, the target speed adjustment is 5 r / min after looking up the table. When the voltage deviation is greater than 1.10 and less than 1.X (if any), the target speed adjustment is 30 r / min after looking up the table, and so on. Similarly, the second threshold is 0.95, the fourth threshold is 0.9, the Kth threshold is 0.Y, and Y is 1-K. 0.025, where K is an even number and greater than zero. When the voltage deviation is less than 0.95 and greater than 0.9, the target speed adjustment is -5 r / min after referring to the table. When the voltage deviation is less than 0.9 and greater than 0.Y (if any), the target speed adjustment is -90 r / min after referring to the table.

[0051] It's important to note that in low-emission constant-speed gas water heater scenarios, the harm caused by a low air-fuel ratio (excessive gas) is far greater than that of a high air-fuel ratio (excessive air). Specifically, when the voltage deviation is significantly lower than the normal deviation, the fan motor's output torque is insufficient, causing a sharp drop in actual speed. This leads to a drastic reduction in airflow, resulting in a severely low air-fuel ratio (excessive gas and insufficient air). At this point, the fuel concentration is high, heat release is more concentrated, and the high temperature causes thermal NOx emissions. x Emissions exceed standards. Insufficient air can also lead to incomplete combustion, resulting in excessive CO emissions, and even flame backfire or flameout. Therefore, it is necessary to significantly reduce the fan speed. Therefore, under normal circumstances, the absolute value of the fourth adjustment is greater than the absolute value of the second adjustment.

[0052] This embodiment provides a control method for a gas water heater. By determining the corresponding adjustment amount through a graded adjustment method, it can quickly suppress the risk of excessive harmful gases caused by excessive gas when the voltage is significantly low. It can also fine-tune the fan speed when the voltage is high to avoid the decrease in combustion efficiency and flame instability caused by excessive air. At the same time, by adapting the disturbance intensity of different deviation ranges through differentiated adjustment ranges, it can effectively avoid air volume fluctuations caused by excessive adjustment. Finally, under complex operating conditions, it can maintain a constant output of fan speed, ensure dynamic matching of air volume and gas supply, and improve the stability and safety of gas water heater operation.

[0053] Based on the first embodiment of this application, in the third embodiment of this application, the same or similar content as the first embodiment can be referred to the above description, and will not be repeated hereafter. In addition, the fan is also set with wind speed limits, namely the maximum speed and the minimum speed. When adjusting the wind speed, it is also necessary to ensure that the adjusted wind speed is between the minimum speed and the maximum speed. Therefore, step S30 also includes steps S31~S32: Step S31: Determine the wind speed limit of the fan.

[0054] Step S32: If the sum of the target speed adjustment amount and the current speed of the fan is within the wind speed limit, adjust the fan speed of the gas water heater based on the target speed adjustment amount.

[0055] In this embodiment, the fan typically has a safe speed limit, i.e., a maximum value or a minimum speed that meets the equipment's operating requirements. Therefore, to avoid the adjusted speed value exceeding the equipment's mechanical capacity, which could lead to fan overload damage or insufficient air supply due to excessively low speed, after obtaining the target speed adjustment value, it is also necessary to determine the fan's wind speed limit value to determine whether wind speed adjustment can be performed based on the wind speed limit value.

[0056] After obtaining the wind speed limit, it is also necessary to calculate the sum of the target speed adjustment and the current speed of the fan. If the sum of the two is within the wind speed limit, the fan speed can be adjusted based on the target speed adjustment. If it exceeds the wind speed limit, the fan speed is directly adjusted based on the wind speed limit that the current speed approaches. For example, if the wind speed limit is 5000 r / min, the current speed is 4980 r / min, and the target speed adjustment is 30 r / min, then the fan speed is adjusted based on the wind speed limit of 5000 r / min, that is, by increasing it by 20 r / min.

[0057] This embodiment provides a control method for a gas water heater. Directly controlling the fan operation based on a target speed adjustment value may result in the adjusted speed exceeding the limit, leading to fan damage or deterioration of combustion conditions. A limit value verification process is set up to perform control only when the adjusted speed is within the fan speed limit, avoiding ineffective control or equipment damage caused by speed adjustment.

[0058] Based on any of the above embodiments, in the fourth embodiment of this application, the content that is the same as or similar to any of the above embodiments can be referred to the above description, and will not be repeated hereafter. In addition, before step S30, step S301 is also included: Step S301: Obtain the current deviation between the current current of the fan and the reference current.

[0059] The aforementioned current deviation can also be a voltage deviation of parameters such as the ratio or difference between currents. The reference current is the theoretical driving current corresponding to the current speed of the fan, representing the current required for normal ventilation.

[0060] It should be noted that the power supply voltage of the fan in a constant-speed gas water heater remains constant. When the flue is blocked, the air pressure inside the flue rises sharply, but the airflow drops to almost zero. Since the fan's output power is proportional to the product of air pressure and airflow, the output power will decrease as the airflow decreases. The input power and output power of the fan motor satisfy P... 入 =P 出 +P 损 When P 出 When P decreases, 入 It also decreases accordingly. At the same time, according to the electrical formula P=UIcosφ, under the premise that the supply voltage U and the power factor cosφ are basically stable, the operating current I will decrease as the power decreases.

[0061] The reference current can be determined by the current speed of the fan. Among these, constant-speed gas water heaters have a calibration line set at the factory, such as... Figure 2 The diagram shows the mapping curve between fan speed (RPM) and fan current (I), with the horizontal axis representing fan speed (RPM) and the vertical axis representing the corresponding reference current. In the fan control system of a constant-speed gas water heater, the reference current value corresponding to each preset speed, the positive correlation slope of the curve, and the overall upward trend are quantitative, reflecting the performance relationship of the fan under ideal operating conditions, and are inherent settings of the equipment. However, the actual fan speed and current during operation are dynamic variables. The actual speed will be adjusted in real time according to the operating conditions such as combustion load and voltage deviation, and the actual current will also change dynamically with factors such as speed changes, grid voltage fluctuations, and changes in duct resistance. At the same time, the compensation coefficient and other professional parameters of this reference curve can also be calibrated and modified by the manufacturer using dedicated diagnostic tools to adapt to the characteristic changes after fan aging or replacement. Therefore, before step S301, the current speed of the fan can be obtained first, and then the reference current corresponding to the current speed can be determined based on the second mapping relationship between the reference current and the fan speed. The second mapping relationship also includes functions, curves, and corresponding relationships.

[0062] After determining the current deviation, it is necessary to check whether the current deviation meets a preset current deviation threshold. This preset current deviation threshold can be a threshold range or a specific value. For example, the current deviation threshold could be A~B%. When the current deviation is within the A~B% range, it is considered to meet the preset current deviation threshold. Optionally, the preset current deviation threshold could also be C%. When the current deviation is less than C%, it is considered to meet the preset current deviation threshold. In other deviation calculation methods, a current deviation greater than C% can be considered to meet the preset current deviation threshold. Therefore, when the current deviation is detected to meet the preset current deviation threshold, the processing action corresponding to step S30 is executed.

[0063] Furthermore, after obtaining the current deviation, if the detected current deviation does not meet the preset current deviation threshold, the gas water heater is turned off. Specifically, if the detected current deviation does not meet the preset current deviation threshold, it indicates that the fan is blocked. In this case, to avoid insufficient air supply leading to incomplete combustion of gas and the generation of toxic and harmful gases, or to prevent safety accidents such as flame backfire or flameout causing gas leaks, the gas water heater needs to be turned off.

[0064] Optionally, before step S10, the current deviation between the current current of the fan and the reference current can be obtained, and then the processing action of step S10 can be executed when the current deviation is detected to meet the preset current deviation threshold. At this time, if the current deviation is detected to not meet the preset current deviation threshold, the gas water heater can also be turned off in advance.

[0065] Optionally, in addition to determining whether the fan is in normal ventilation mode by measuring the fan's operating current, a real-time air pressure sensor installed at the fan inlet can also be used to collect the inlet's air pressure. This air pressure is then used to determine whether the fan is in normal ventilation mode. Abnormal air resistance can cause the air pressure to deviate from the standard range; therefore, real-time air pressure is collected first, and then compared with a preset normal air pressure threshold to determine whether the fan is in normal ventilation mode. For example, if the real-time air pressure is greater than the normal air pressure, then the fan is considered to be in normal ventilation mode.

[0066] This embodiment provides a control method for a gas water heater. The ventilation status is determined by the voltage deviation between the current and the reference current. Based on real-time electrical parameters, it identifies whether there is a hidden danger of insufficient ventilation in the fan, avoids safety accidents such as incomplete combustion of gas producing toxic gases or backfire leakage, and provides a safe adjustment environment for subsequent closed-loop iterative adjustment of the fan speed.

[0067] Based on any of the above embodiments, in the fifth embodiment of this application, the content that is the same as or similar to any of the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, the step of determining the reference thermal voltage before step S10 includes steps S01~S02: Step S01: Obtain the current gas volume of the gas water heater.

[0068] Step S02: Determine the reference thermal voltage based on the pre-configured mapping relationship between the gas quantity and the reference thermal voltage.

[0069] In this embodiment, the reference thermal voltage is the ideal flame temperature voltage value matched with a specific gas quantity. The gas quantity directly determines the combustion intensity. Generally, the larger the gas quantity, the more fuel participates in combustion, the higher the flame combustion intensity, and the higher the corresponding flame temperature. At this time, the thermal voltage output by the thermocouple is also higher. Conversely, the smaller the gas quantity, the lower the combustion intensity, and the lower the thermal voltage.

[0070] It should be noted that gas water heaters are labeled with a condition such as... Figure 3 The mapping relationship between the preset thermocouple voltage -V and the preset proportional valve -PWM shown is a quantitative reference standard for gas supply and ideal combustion conditions. The reference thermocouple voltage values ​​corresponding to each preset PWM value, as well as the overall trend and slope of the curves, are determined by the inherent properties of the burner hardware and the calorific value of the gas, representing a fixed matching relationship between gas supply and combustion feedback under ideal combustion conditions. However, in actual operation, the actual proportional valve PWM value is dynamically adjusted according to operating conditions such as hot water load and outlet water temperature requirements, while the actual thermocouple voltage value changes in real time with factors such as combustion state, airflow fluctuations, and gas pressure changes.

[0071] Therefore, the mapping relationship between the current gas flow rate of the gas water heater and the reference thermal voltage can be read simultaneously or subsequently obtained. Then, using this mapping relationship and the current gas flow rate, the reference thermal voltage is determined. This allows for subsequent correction of the fan speed based on the voltage deviation between the real-time thermal voltage detected by the thermocouple and the reference thermal voltage, ensuring that the actual thermal voltage approaches the reference thermal voltage.

[0072] Optionally, before step S10, steps S04 to S05 are also included: Step S04: In response to the start-up process of the gas water heater, determine the amount of gas associated with the start-up process.

[0073] Step S05: Start the gas process of the gas water heater and control the fan operation based on the fan speed corresponding to the gas volume.

[0074] In this embodiment, the gas water heater needs to operate based on a preset initial air-fuel ratio during the startup phase to avoid problems such as unstable flame, flameout, or incomplete combustion of gas producing harmful gases during startup caused by asynchronous gas and air supply. Therefore, after the gas water heater detects the startup process (such as turning on), it responds to the process and determines the corresponding gas volume, which is usually a preset gas volume. Subsequently, it initiates the gas supply process and controls the fan operation based on the fan speed corresponding to the gas volume, providing a good equipment operation foundation for subsequent closed-loop combustion control.

[0075] This embodiment provides a control method for a gas water heater, which obtains the mapping relationship between the reference thermal voltage and the gas quantity and determines the current reference thermal voltage accordingly. This provides a precise and quantifiable target anchor point for the combustion control of the gas water heater, thereby providing a reliable basis for subsequent real-time thermal voltage comparison and analysis, and improving the reliability of equipment operation.

[0076] Based on any of the above embodiments, in the sixth embodiment of this application, the content that is the same as or similar to any of the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, after step S30, steps S40~S50 are also included: Step S40: Obtain the target rotational speed of the fan.

[0077] Step S50: Update the mapping relationship between gas volume and fan speed based on the target rotational speed.

[0078] In this embodiment, the gas water heater is pre-set at the factory. Figure 4 The air distribution curve shown represents the fourth mapping relationship between the preset proportional valve (PWM) and the preset fan speed (RPM). This curve is a fixed mapping relationship calibrated under standard laboratory conditions, such as stable gas pressure, clean air ducts, and constant ambient temperature. The reference fan speed values ​​corresponding to each preset PWM value, as well as the overall slope and upward trend of the curve, are determined by inherent hardware attributes such as burner air-fuel ratio design and heat load characteristics. These serve as a fixed reference for matching gas supply and airflow under standard operating conditions. In actual operation, the PWM value will dynamically adjust according to hot water load and outlet water temperature requirements, and the actual fan speed will change in real time with voltage fluctuations, changes in air duct resistance, and combustion deviation corrections—dynamically changing operating parameters. This air distribution curve includes matching data for each preset value, curve trends, and slopes. As an inherent setting calibrated at the factory based on standard laboratory conditions, it cannot be modified by the user. However, the manufacturer can use dedicated diagnostic tools to calibrate and modify the curve compensation coefficients and deviation corrections, making the air distribution relationship more closely match actual operating needs.

[0079] During actual field operation, the equipment will continuously face dynamic operating condition deviations such as gas pressure fluctuations (pressure drops during peak gas consumption), changes in duct resistance (due to differences in gas composition across countries / regions), dust accumulation after long-term use, duct bends caused by installation location, and environmental temperature differences (such as changes in air density at low winter temperatures). These deviations can cause a misalignment between the initially preset air distribution strategy and actual combustion requirements. In other words, the air distribution strategy corresponding to the current gas volume may not meet the actual combustion needs. Furthermore, to avoid readjustment after subsequent equipment restarts, the registration curve between the current gas volume and fan speed needs to be updated based on the target speed. This ensures that the air distribution strategy continuously adapts to the dynamic operating conditions on site, guaranteeing efficient and stable combustion. After equipment restarts, the optimized curve can be directly used without repeated calibration.

[0080] Specifically, by determining the target fan speed under current operating conditions and dynamically updating the air distribution curve, the gas water heater can calibrate the matching relationship between gas volume and air volume in real time based on actual combustion feedback. This allows the air distribution strategy to adapt to current gas supply capacity, duct resistance, and ambient temperature, rather than relying on fixed factory calibration values. Consequently, even with significant differences in gas composition and exhaust duct lengths across different regions and countries, the fan speed is dynamically adjusted based on the current thermocouple voltage to maintain stable gas combustion while reducing emissions. This enhances the reliability and adaptability of the equipment in complex on-site environments.

[0081] Optionally, in addition to updating the mapping relationship between gas volume and fan speed, a coupled optimization model of target speed and multi-dimensional combustion parameters can be established based on the target speed and real-time collected combustion state parameters such as flame intensity, carbon monoxide concentration in flue gas, and hot water yield. This model can be used to correct the dynamic compensation coefficient of the reference thermal voltage so that the reference thermal voltage can adapt to the fan operating characteristics under different wind resistance and different gas source calorific values.

[0082] Optionally, the target rotation speed, the voltage deviation corresponding to that rotation speed, the wind pressure data, and the combustion parameters can also be uploaded to the cloud-based equipment management platform for batch operating condition threshold calibration and fault early warning model training of the same model of gas water heaters.

[0083] Optionally, it can also link the real-time opening data of the gas valve to generate a synchronous matching curve between the target speed and the optimal gas valve opening. When the same deviation in the heat-voltage ratio is subsequently detected, the matching curve can be directly called to achieve coordinated fine-tuning of the fan speed and the gas valve opening, further shortening the control response time and improving combustion stability.

[0084] For example, to help understand the implementation flow of the control method for a gas water heater obtained by combining the above embodiments, please refer to... Figure 5 , Figure 5A brief flow schematic diagram of a control method for a gas water heater is provided. Specifically: After the gas water heater is turned on, it first starts running according to a preset valve body and fan air distribution curve. Subsequently, the current fan current and the current thermal voltage are read in real time. Then, the air block current is judged through the read power parameters. In this process, by calculating the ratio A of the current fan current to the reference current I0, when A < B%, it indicates that the current has decreased due to blockage of the device, and at this time, it is directly judged as a smoke exhaust blockage and the water heater is turned off; if A ≥ B%, it means that the current fan is in a normal state. Then, the ratio R of the current thermal voltage V to the reference thermal voltage V0 is calculated, and the rotation speed adjustment is judged according to R. If 95% ≤ R ≤ 105%, that is, the ratio is within the preset interval, the wind speed stops adjusting; If R ≥ 110%, the fan rotation speed is adjusted by +30 r / min; If 105% < R < 110%, the fan rotation speed is adjusted by +5 r / min; If R ≤ 90%, the fan rotation speed is adjusted by -90 r / min; If 90% < R < 95%, the fan rotation speed is adjusted by -5 r / min.

[0085] It can be understood that when the voltage deviation, that is, the ratio R, is large, in order to avoid the device from shutting down, a large wind speed needs to be adjusted. If R ≤ 90%, the fan rotation speed is adjusted by -90 r / min. When the voltage deviation is small, the adjusted rotation speed is relatively small. At the same time, the above rotation speed adjustment amount is only for explanation and is not a limitation to this application.

[0086] After the rotation speed adjustment is completed, the system sets the air adjustment limit, limiting the maximum air adjustment volume to be less than C%, to avoid the adjusted fan rotation speed exceeding the air adjustment limit value, thereby preventing the fan from running at an ultra-high speed for a long time and causing motor overload, or avoiding excessive heat loss due to excessive air带走过多热量造成热效率下降。

[0087] Finally, the preset wind speed is adjusted again according to the air adjustment volume of the thermocouple, enabling the system to dynamically calibrate the initial preset air distribution curve based on the feedback of actual combustion, compensating for the difference between the factory calibration value and the on-site working conditions, making the air distribution strategy more in line with the current real combustion demand. Then the entire process returns to the initial link and loops, realizing continuous closed-loop monitoring and dynamic correction, and ensuring combustion safety and efficiency.

[0088] This application provides a gas water heater, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the control method of the gas water heater in the above first embodiment.

[0089] Next, refer to Figure 6 It shows a structural schematic diagram of a gas water heater suitable for implementing the embodiments of this application. Figure 6 The gas water heater shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of this application.

[0090] like Figure 6 As shown, the gas water heater may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.) that can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. The RAM 1004 also stores various programs and data required for the operation of the gas water heater. The processing device 1001, the ROM 1002, and the RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 1003 including, for example, magnetic tape, hard disk, etc.; and communication devices 1009. Communication device 1009 allows the gas water heater to communicate wirelessly or wiredly with other devices to exchange data. Although the figures show gas water heaters with various systems, it should be understood that implementation or possession of all the systems shown is not required. More or fewer systems may be implemented alternatively.

[0091] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from read-only memory 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0092] The gas water heater provided in this application, employing the control method of the gas water heater in the above embodiments, can solve the technical problem of low gas combustion stability in gas water heaters under complex operating conditions. Compared with the prior art, the beneficial effects of the gas water heater provided in this application are the same as those of the control method of the gas water heater provided in the above embodiments, and other technical features of this gas water heater are the same as those disclosed in the method of the previous embodiment, and will not be repeated here.

[0093] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0094] 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 that can be easily conceived by those skilled in the art within the scope of the technology 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.

[0095] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the control method of the gas water heater in the above embodiments.

[0096] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory, read-only memory, erasable programmable read-only memory (EPROM, or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, radio frequency (RF), etc., or any suitable combination thereof.

[0097] The aforementioned computer-readable storage medium may be included in the gas water heater; or it may exist independently and not be installed in the gas water heater.

[0098] The aforementioned computer-readable storage medium carries one or more programs that, when executed by the gas water heater, cause the gas water heater to: Determine the voltage deviation between the current thermocouple voltage and the reference thermocouple voltage; Based on the first mapping relationship between the speed adjustment amount and the voltage deviation, the target speed adjustment amount corresponding to the voltage deviation is determined; Adjust the fan speed of the gas water heater according to the target speed adjustment amount.

[0099] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0100] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0101] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0102] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the control method of the gas water heater described above, which can solve the technical problem of low gas combustion stability in gas water heaters under complex operating conditions. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as the beneficial effects of the control method of the gas water heater provided in the above embodiments, and will not be repeated here.

[0103] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A control method for a gas water heater, characterized in that, The control method for the gas water heater includes: Obtain the voltage deviation between the current thermocouple voltage and the reference thermocouple voltage; Based on the preset first mapping relationship between the voltage deviation and the speed adjustment amount, the target speed adjustment amount corresponding to the voltage deviation is determined; wherein, the sum of the target speed adjustment amount and the current speed of the fan is within the wind speed limit value; Adjust the fan speed of the gas water heater according to the target speed adjustment amount.

2. The control method for a gas water heater as described in claim 1, characterized in that, The step of determining the target speed adjustment amount corresponding to the voltage deviation based on a preset first mapping relationship between the voltage deviation and the speed adjustment amount includes: If the voltage deviation is greater than the first threshold, the target speed adjustment amount is determined to be positive. If the voltage deviation is less than the second threshold, the target speed adjustment amount is determined to be negative; If the voltage deviation is greater than or equal to the second threshold and less than or equal to the first threshold, the target speed adjustment is determined to be zero. Among them, the first threshold is greater than the second threshold, the first threshold is greater than the normal deviation value, and the second threshold is less than the normal deviation value.

3. The control method for a gas water heater as described in claim 2, characterized in that, The step of determining that the target speed adjustment amount is positive if the voltage deviation is greater than the first threshold includes: If the voltage deviation is greater than the first threshold and less than the third threshold, the target speed adjustment amount is determined to be the first adjustment amount. If the voltage deviation is greater than the third threshold, the target speed adjustment amount is determined to be the second adjustment amount. The third threshold is greater than the first threshold, the second adjustment amount is greater than the first adjustment amount, and both the first adjustment amount and the second adjustment amount are positive values.

4. The control method for a gas water heater as described in claim 2, characterized in that, The step of determining that the target speed adjustment amount is negative if the voltage deviation is less than the second threshold includes: If the voltage deviation is greater than the fourth threshold and less than the second threshold, the target speed adjustment amount is determined to be the third adjustment amount; If the voltage deviation is less than the fourth threshold, the target speed adjustment amount is determined to be the fourth adjustment amount. The fourth threshold is less than the second threshold, the fourth adjustment amount is less than the third adjustment amount, and both the third and fourth adjustment amounts are negative.

5. The control method for a gas water heater as described in claim 1, characterized in that, Before adjusting the fan speed of the gas water heater according to the target speed adjustment amount, the control method for the gas water heater further includes: Obtain the current deviation between the current current of the fan and the reference current; If the current deviation is detected to meet the preset current deviation threshold, the step of adjusting the fan speed of the gas water heater according to the target speed adjustment amount is executed.

6. The control method for a gas water heater as described in claim 5, characterized in that, The control method for the gas water heater also includes: If the current deviation is detected to be inconsistent with the preset current deviation threshold, the gas water heater is turned off.

7. The control method for a gas water heater as described in claim 1, characterized in that, The steps for determining the reference thermal voltage include: Obtain the current gas volume of the gas water heater; The reference thermal voltage is determined based on a pre-configured second mapping relationship between the gas quantity and the reference thermal voltage.

8. The control method for a gas water heater as described in any one of claims 1 to 7, characterized in that, After the step of adjusting the fan speed of the gas water heater according to the target speed adjustment amount, the control method of the gas water heater further includes: Obtain the target rotational speed of the fan; Based on the target rotational speed, update the third mapping relationship between gas volume and fan speed.

9. A gas water heater, characterized in that, The gas water heater includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the control method for the gas water heater as described in any one of claims 1 to 8.

10. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the control method for a gas water heater as described in any one of claims 1 to 8.

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