Fully premixed gas water heater, control method thereof and computer readable storage medium

Abstract

The application relates to the technical field of full premix gas water heaters, and discloses a full premix gas water heater, a control method thereof and a computer readable storage medium. The full premix gas water heater comprises a premixing cavity, a fan, an air door, a driving device and a position detection device, the driving device is used for directly driving the air door, the position detection device is used for detecting the opening degree of the air door, the control method comprises the following steps: in response to a heating instruction, a first air door control signal is generated, or a first air door control signal and a first fan control signal are generated; the first air door control signal is sent to the driving device, so that the driving device adjusts the opening degree of the air door, and the actual opening degree of the air door is received by the position detection device; and / or the first fan control signal is sent to the fan, so that the fan adjusts the rotating speed of the fan according to the first fan control signal. In the above manner, the control efficiency of the air door can be improved, the time for air to enter the premixing cavity is shortened, and the heating efficiency is improved.

Description

Fully premixed gas water heater and its control method, computer-readable storage medium Technical Field

[0001] This application relates to the field of fully premixed gas water heater technology, and in particular to fully premixed gas water heaters and their control methods, as well as computer-readable storage media. Background Technology

[0002] Traditional fully premixed gas water heaters generally use a fixed damper design, resulting in insufficient precision in controlling the gas-air mixing ratio and large fluctuations in combustion efficiency. At the same time, the system lacks real-time dynamic adjustment capabilities and a precise location feedback mechanism, resulting in a narrow power coverage range that cannot adapt to large-scale load changes, impacting energy efficiency and user experience. Summary of the Invention

[0003] The fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, can improve the control efficiency of the damper and accelerate the time for air to enter the premixing chamber, thereby improving the heating efficiency.

[0004] In a first aspect, this application provides a control method for a fully premixed gas water heater. The gas water heater includes a premixing chamber, a fan, a damper, a drive device, and a position detection device. The drive device is used to directly drive the damper, and the position detection device is used to detect the opening degree of the damper. The control method includes: in response to a heating command, generating a first damper control signal, or generating a first damper control signal and a first fan control signal; sending the first damper control signal to the drive device to adjust the opening degree of the damper, and receiving feedback from the position detection device on the actual opening degree of the damper; and / or sending the first fan control signal to the fan to adjust the fan speed according to the first fan control signal.

[0005] The method further includes, after receiving feedback from the position detection device on the actual opening degree of the damper, adjusting the first damper control signal according to the actual opening degree to obtain the second damper control signal, and / or adjusting the first fan control signal to obtain the second fan control signal; sending the second damper control signal to the damper drive device, and / or sending the second fan control signal to the fan.

[0006] The process includes: adjusting the first damper control signal to obtain a second damper control signal based on the actual opening degree; and / or adjusting the first fan control signal to obtain a second fan control signal, including: acquiring the target opening degree corresponding to the first fan control signal; adjusting the first fan control signal to obtain a second fan control signal in response to the actual opening degree being greater than the target opening degree; wherein the second fan control signal is used to instruct the fan to reduce its speed; and / or adjusting the first damper control signal to obtain a second damper control signal; the second damper control signal is used to instruct the drive device to reduce the damper opening degree; adjusting the first fan control signal to obtain a second fan control signal in response to the actual opening degree being less than the target opening degree; wherein the second fan control signal is used to instruct the fan to increase its speed; and / or adjusting the first damper control signal to obtain a second damper control signal; the second damper control signal is used to instruct the drive device to increase the damper opening degree; and maintaining the first damper control signal and the first fan control signal in response to the actual opening degree being equal to the target opening degree.

[0007] The process of generating a first damper control signal, or generating a first damper control signal and a first fan control signal, in response to a heating command includes: acquiring the current demand load; generating a heating command based on the current demand load; and generating a first damper control signal, or generating a first damper control signal and a first fan control signal, in response to the heating command.

[0008] The heating command generated based on the current demand load includes: generating a first heating command in response to the current demand load being greater than the previous demand load; generating a second heating command in response to the current demand load being less than the previous demand load; and generating a third heating command in response to the current demand load being equal to the previous demand load. In response to the heating command, a first damper control signal, or a combination of a first damper control signal and a first fan control signal, is generated, including: generating a first damper control signal in response to the first heating command, or a combination of a first damper control signal and a first fan control signal; the first damper control signal is used to instruct the drive device to increase... The opening degree of the damper is controlled by a first fan control signal, which instructs the fan to increase its speed. In response to a second heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated. The first damper control signal instructs the drive device to decrease the damper opening, and the first fan control signal instructs the fan to decrease its speed. In response to a third heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated. The first damper control signal instructs the drive device to maintain the current damper opening, and the first fan control signal instructs the fan to maintain its current speed.

[0009] The process of adjusting the first damper control signal to obtain the second damper control signal based on the actual opening degree, and / or adjusting the first fan control signal to obtain the second fan control signal, includes: acquiring the current gas flow signal; adjusting the first damper control signal to obtain the second damper control signal based on the current gas flow signal and the actual opening degree, and / or adjusting the first fan control signal to obtain the second fan control signal.

[0010] The process of adjusting the first damper control signal to obtain the second damper control signal and / or adjusting the first fan control signal to obtain the second fan control signal, based on the current gas flow signal and the actual opening degree, includes: determining the actual mixing ratio based on the current gas flow signal and the actual opening degree; the actual mixing ratio being the mixing ratio of gas and air; adjusting the first damper control signal to obtain the second damper control signal and / or adjusting the first fan control signal to obtain the second fan control signal based on the actual mixing ratio.

[0011] The method further includes, after receiving feedback from the position detection device on the actual opening of the damper, triggering a damper fault warning in response to the actual opening being less than or greater than the target opening and lasting for a duration longer than a preset duration.

[0012] Secondly, this application provides a fully premixed gas water heater, which includes: a premixing chamber; a fan; a damper; a drive device for directly driving the damper; a position detection device for detecting the opening degree of the damper; a processor connected to the drive device, the position detection device, and the fan; and a memory connected to the processor for storing a computer program. The processor executes the computer program to implement the method provided in the first aspect.

[0013] Thirdly, this application provides a computer-readable storage medium for storing a computer program, which, when executed by a processor, is used to implement the method provided in the first aspect.

[0014] The beneficial effects of the embodiments of this application are as follows: Unlike the prior art, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, include a premixed gas water heater comprising a premixing chamber, a fan, a damper, a drive device, and a position detection device. The drive device is used to directly drive the damper, and the position detection device is used to detect the opening degree of the damper. During the heating process, the drive device directly drives the damper, which, compared to a fixed damper and a passively controlled damper, can improve the control efficiency of the damper and accelerate the time for air to enter the premixing chamber, thereby improving the heating efficiency. Furthermore, the position detection device provides feedback on the actual opening degree of the damper, facilitating fine adjustment of the opening degree and enabling precise control of the damper opening. This allows for precise control of the gas-air mixing ratio in the premixing chamber, which is beneficial for further reducing the minimum heat load of the fully premixed gas water heater and meeting more hot water usage needs. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0016] Figure 1 is a flowchart illustrating the first embodiment of the control method for a fully premixed gas water heater provided in this application.

[0017] Figure 2 is a flowchart illustrating the second embodiment of the control method for a fully premixed gas water heater provided in this application.

[0018] Figure 3 is a flowchart of an embodiment after receiving feedback from the position detection device on the actual opening of the damper;

[0019] Figure 4 is a flowchart of an embodiment of step 31 in Figure 3;

[0020] Figure 5 is a flowchart of another embodiment of step 31 in Figure 3;

[0021] Figure 6 is a flowchart of an embodiment of step 52 in Figure 5;

[0022] Figure 7 is a flowchart illustrating the third embodiment of the control method for a gas water heater provided in this application;

[0023] Figure 8 is a structural schematic diagram of an embodiment of the fully premixed gas water heater provided in this application;

[0024] Figure 9 is a schematic diagram of an embodiment of the computer-readable storage medium provided in this application. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It is understood that the specific embodiments described herein are only for explaining this application and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings, not all structures. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0026] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0027] Traditional fully premixed gas water heaters generally use a fixed damper design, resulting in insufficient precision in controlling the gas-air mixing ratio and large fluctuations in combustion efficiency. At the same time, the system lacks real-time dynamic adjustment capabilities and a precise location feedback mechanism, resulting in a narrow power coverage range that cannot adapt to large-scale load changes, impacting energy efficiency and user experience.

[0028] Based on this, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, include a premixed gas water heater comprising a premixing chamber, a fan, a damper, a drive device, and a position detection device. The drive device directly drives the damper, and the position detection device detects the opening degree of the damper. During the heating process, the drive device directly drives the damper, which, compared to a fixed damper or a passively controlled damper, improves the control efficiency of the damper and accelerates the time for air to enter the premixing chamber, thereby improving heating efficiency. Furthermore, the position detection device provides feedback on the actual opening degree of the damper, facilitating fine adjustments to the opening degree and enabling precise control of the damper opening. This allows for precise control of the gas-air mixing ratio in the premixing chamber, further reducing the minimum heat load of the fully premixed gas water heater and meeting greater hot water usage needs. See any of the following embodiments for specific technical solutions.

[0029] The core principle of fully premixed gas combustion technology is to fully mix the gas and air in a premixing chamber before the gas enters the combustion chamber, breaking the dependence of traditional combustion methods on the diffusion process, thereby improving combustion speed and thermal efficiency.

[0030] Referring to Figure 1, Figure 1 is a flowchart illustrating a first embodiment of the control method for a fully premixed gas water heater provided in this application. The fully premixed gas water heater includes a premixing chamber, a fan, a damper, a drive device, and a position detection device. The drive device directly drives the damper, and the position detection device detects the opening degree of the damper. The control method includes:

[0031] Step 11: In response to the heating command, generate the first damper control signal.

[0032] In some embodiments, the opening degree of the damper determines the air intake volume into the premixing chamber. Based on this, when the fully premixed gas water heater generates a heating command, a first damper control signal is generated accordingly to control the drive device corresponding to the damper.

[0033] In some embodiments, the fan is also a major factor in determining the amount of air entering the premixing chamber. In some embodiments, when the fan is set to a constant speed, the amount of air entering the premixing chamber can be determined simply by adjusting the magnitude of the first damper control signal. The drive unit can achieve more precise and fine damper opening control, such as controlling the damper opening from any degree from 0 to 100. 100 represents the maximum damper opening.

[0034] In some embodiments, in response to a heating command, the operating mode of the fan is obtained, and in response to the fan operating at a fixed speed, a first damper control signal is generated based on the fixed speed.

[0035] The mixing ratio of gas and air in the premixing chamber can be known in advance during heating. When the fan operates at a fixed speed, the corresponding damper opening can be calculated. Based on this, a first damper control signal is generated to control the drive device to bring the damper to that opening.

[0036] Step 12: Send the first damper control signal to the drive device so that the drive device adjusts the opening of the damper and receives feedback from the position detection device on the actual opening of the damper.

[0037] In some embodiments, the position detection device may be configured as a contact position detection device.

[0038] In some embodiments, the position detection device may be configured as a non-contact position detection device.

[0039] The position of the damper can be detected in real time using a position detection device, and the position of the damper directly reflects the opening degree of the damper. The larger the opening degree of the damper, the greater the air intake into the premixing chamber, and the smaller the opening degree of the damper, the smaller the air intake into the premixing chamber.

[0040] In this embodiment, during the heating process, the damper is directly driven by a drive device. Compared with fixed dampers and passively controlled dampers, this improves the control efficiency of the damper and speeds up the time for air to enter the premixing chamber, thereby improving heating efficiency. Furthermore, the actual opening degree of the damper is fed back by a position detection device, which facilitates fine adjustment of the opening degree. This allows for precise control of the damper opening, enabling precise control of the gas-air mixing ratio in the premixing chamber. This further reduces the minimum heat load of the fully premixed gas water heater, meeting more hot water usage needs.

[0041] Referring to Figure 2, which is a flowchart illustrating a second embodiment of the control method for a fully premixed gas water heater provided in this application, the fully premixed gas water heater includes a fan, a damper, a drive device, and a position detection device. The drive device directly drives the damper, and the position detection device detects the opening degree of the damper. The control method includes:

[0042] Step 21: In response to the heating command, generate a first damper control signal and a first fan control signal.

[0043] In some embodiments, the opening degree of the damper and the fan speed determine the air intake volume into the premixing chamber. Based on this, when the fully premixed gas water heater generates a heating command, a first damper control signal and a first fan control signal are generated accordingly.

[0044] In some embodiments, the mixing ratio of gas and air in the premixing chamber can be known in advance during heating. Based on this, the corresponding opening degree of the damper and the fan speed can be calculated, thereby precisely controlling the amount of air entering the premixing chamber. Based on this, a first damper control signal is generated to control the drive device to reach the damper opening degree, and a first fan control signal is generated to allow the fan to reach the fan speed.

[0045] Step 22: Send the first damper control signal to the drive device so that the drive device adjusts the opening of the damper and receives feedback from the position detection device on the actual opening of the damper.

[0046] In some embodiments, step 22 has the same or similar technical solutions as the other embodiments of this application, and will not be described in detail here.

[0047] Step 23: Send the first fan control signal to the fan so that the fan speed is adjusted according to the first fan control signal.

[0048] In some embodiments, steps 22 and 23 are sent synchronously.

[0049] In some embodiments, the first damper control signal can be sent before the first fan control signal. That is, if the first damper control signal is sent before the first fan control signal, the drive device will drive the damper to open before the fan. During this process, the fan speed has not yet increased to the required speed, the air pressure (airflow disturbance) on the damper is relatively small, and the drive device can more accurately control the opening degree of the damper.

[0050] In this embodiment, during the heating process, the damper is directly driven by a drive device. Compared to fixed dampers and passively controlled dampers, this improves the control efficiency of the damper, accelerates the time for air to enter the premixing chamber, and thus enhances heating efficiency. Furthermore, the fan and damper are decoupled (independently controlled), and their correspondence is determined when the first damper control signal and the first fan control signal are generated. In subsequent control, each is individually controlled by its corresponding control signal. Unlike passively controlled dampers, which require fan rotation to control the damper opening, this embodiment improves the accuracy of damper control. Moreover, the actual damper opening is fed back by a position detection device, facilitating fine adjustments and precise control of the damper opening. This allows for precise control of the gas-air mixing ratio in the premixing chamber, further reducing the minimum heat load of the fully premixed gas water heater and meeting greater hot water usage needs.

[0051] In some embodiments, referring to FIG3, after receiving feedback from the position detection device on the actual opening degree of the damper, the method further includes:

[0052] Step 31: Adjust the first damper control signal according to the actual opening to obtain the second damper control signal, and / or adjust the first fan control signal to obtain the second fan control signal.

[0053] In some embodiments, considering that the heating process is a continuous process, after receiving the actual opening degree, it is necessary to decide whether to adjust the first damper control signal and / or the first fan control signal according to the actual opening degree, so as to correct the control of the damper and / or the fan, so that the actual mixing ratio in the premixing chamber can quickly reach the preset mixing ratio.

[0054] In some embodiments, referring to FIG4, step 31 may be the following process:

[0055] Step 311: Obtain the target opening degree corresponding to the first fan control signal.

[0056] In some embodiments, the target opening is the theoretical opening. That is, when the drive device has no error, the damper can reach the target opening by following the first fan control signal. However, in actual operation, the drive device is often affected by different environments, wear levels, etc., and errors often occur. That is, under the control of the first fan control signal, the actual opening may differ from the target opening. Therefore, closed-loop control is required to ensure that the drive device can maintain the damper opening at the target opening during this process.

[0057] Step 312: In response to the actual opening being greater than the target opening, adjust the first fan control signal to obtain the second fan control signal; and / or, adjust the first damper control signal to obtain the second damper control signal.

[0058] It is understandable that the second fan control signal and the second damper control signal in step 312 are generated under the premise that the actual opening degree is greater than the target opening degree.

[0059] In some embodiments, if the actual opening is greater than the target opening, the proportion of air entering the premixing chamber will be greater than the preset proportion when the fan speed is error-free. Based on this, the fan speed can be adjusted to reduce the amount of air entering the premixing chamber, or the opening of the damper can be adjusted to reduce the amount of air entering the premixing chamber.

[0060] For example, in response to the actual opening being greater than the target opening, the first fan control signal is adjusted to obtain a second fan control signal, which is used to instruct the fan to reduce its speed. In another application scenario, if the drive device has poor accuracy and cannot precisely control the damper to reach the target opening, the fan speed can be adjusted to reduce the airflow velocity at a large opening, thereby reducing the proportion of air entering the premixing chamber.

[0061] For example, in response to the actual opening being greater than the target opening, the first damper control signal is adjusted to obtain the second damper control signal; the second damper control signal is used to instruct the drive device to reduce the damper opening. In one application scenario, the actual opening is greater than the target opening, and the fan speed is at its minimum speed and cannot be further reduced, so the damper opening can be reduced to decrease the proportion of air entering the premixing chamber.

[0062] For example, in response to the actual opening being greater than the target opening, the first fan control signal is adjusted to obtain the second fan control signal; and the first damper control signal is adjusted to obtain the second damper control signal. The second fan control signal is used to instruct the fan to reduce its speed, and the second damper control signal is used to instruct the drive device to reduce the damper opening. In one application scenario, when the actual opening is greater than the target opening, if neither the damper nor the fan is at its limit (e.g., maximum opening, minimum opening, maximum wind speed, minimum wind speed, etc.), both can be adjusted together to obtain the second fan control signal and the second damper control signal.

[0063] Step 313: In response to the actual opening being less than the target opening, adjust the first fan control signal to obtain the second fan control signal; and / or, adjust the first damper control signal to obtain the second damper control signal.

[0064] It is understandable that the second fan control signal and the second damper control signal in step 313 are generated under the premise that the actual opening degree is less than the target opening degree.

[0065] In some embodiments, if the actual opening is less than the target opening, the proportion of air entering the premixing chamber will be less than the preset proportion when the fan speed is error-free. Based on this, the fan speed can be adjusted to increase the amount of air entering the premixing chamber, or the opening of the damper can be adjusted to increase the amount of air entering the premixing chamber.

[0066] In some embodiments, in response to the actual opening being less than the target opening, the first fan control signal is adjusted to obtain a second fan control signal. The second damper control signal is used to instruct the drive device to increase the damper opening. For example, in an application scenario where the drive device has poor accuracy and cannot precisely control the damper to reach the target opening, the fan speed can be adjusted to increase the airflow velocity at a small opening, thereby increasing the proportion of air entering the premixing chamber.

[0067] In some embodiments, in response to the actual opening being less than the target opening, the first damper control signal is adjusted to obtain a second damper control signal. The second fan control signal is used to instruct the fan to increase its speed. In one application scenario, if the actual opening is less than the target opening and the fan speed is at its maximum and cannot be increased further, the damper opening can be increased to increase the proportion of air entering the premixing chamber.

[0068] In some embodiments, in response to the actual opening being less than the target opening, the first fan control signal is adjusted to obtain the second fan control signal; and the first damper control signal is adjusted to obtain the second damper control signal. In one application scenario, when the actual opening is less than the target opening, if neither the damper nor the fan is in its limit state (e.g., maximum opening, minimum opening, maximum wind speed, minimum wind speed, etc.), both can be adjusted together to obtain the second fan control signal and the second damper control signal. The second damper control signal is used to instruct the drive device to increase the damper opening, and the second fan control signal is used to instruct the fan to increase its speed.

[0069] Step 314: In response to the actual opening degree being equal to the target opening degree, maintain the first damper control signal and maintain the first fan control signal.

[0070] When the actual opening equals the target opening, the first damper control signal and the first fan control signal can be maintained. If the mixing ratio changes in the next moment, the fan and damper will be adjusted again according to the new mixing ratio.

[0071] In some embodiments, referring to Figure 5, step 31 can also be the following process:

[0072] Step 51: Obtain the current gas flow signal.

[0073] Since the premixing chamber primarily mixes fuel gas and air, the current fuel gas flow rate signal can be obtained. This flow rate signal represents the volume of fuel gas entering the premixing chamber per unit time.

[0074] Step 52: Based on the current gas flow signal and the actual opening degree, adjust the first damper control signal to obtain the second damper control signal, and / or adjust the first fan control signal to obtain the second fan control signal.

[0075] In some embodiments, referring to FIG6, step 52 may be the following process:

[0076] Step 521: Determine the actual mixing ratio based on the current gas flow signal and the actual opening degree; the actual mixing ratio is the mixing ratio of gas and air.

[0077] Step 522: Adjust the first damper control signal according to the actual mixing ratio to obtain the second damper control signal, and / or adjust the first fan control signal to obtain the second fan control signal.

[0078] Step 32: Send the second damper control signal to the damper drive device, and / or send the second fan control signal to the fan.

[0079] In some embodiments, if only the second damper control signal is obtained in step 31, the second damper control signal is sent to the damper drive device, and the fan still operates according to the first fan control signal.

[0080] In some embodiments, if only the second fan control signal is obtained in step 31, the second fan control signal is sent to the fan, and the drive device still operates according to the first damper control signal.

[0081] In some embodiments, if the second damper control signal and the second fan control signal are obtained in step 31, the second damper control signal is sent to the damper drive device, and the second fan control signal is sent to the fan.

[0082] It is understandable that, since the heating process is continuous, the damper control signal and / or fan control signal will be rapidly adjusted in response to the load changes during heating in order to meet the current load requirements.

[0083] In this embodiment, since the premixing process is continuous, after receiving feedback from the position detection device on the actual opening of the damper, it is necessary to ensure precise control of the fan and damper to ensure accurate mixing of gas and air during the premixing process. Therefore, the first damper control signal and / or the first fan control signal can be adjusted according to the actual opening, so that the entire process forms a closed-loop control, which can accurately control the damper opening, so as to achieve precise control of the gas-air mixing ratio in the premixing chamber. This is beneficial to further reduce the minimum heat load of the fully premixed gas water heater and meet more hot water usage needs.

[0084] Referring to Figure 7, which is a flowchart illustrating a third embodiment of the control method for a gas water heater provided in this application, the gas water heater includes a fan, a damper, a drive device, and a position detection device. The drive device directly drives the damper, and the position detection device detects the opening degree of the damper. The control method includes:

[0085] Step 71: Obtain the current demand load.

[0086] In some embodiments, the current demand load can be determined based on the current demand temperature. For example, a demand water temperature of 20 degrees Celsius corresponds to a corresponding demand load. Similarly, a demand water temperature of 30 degrees Celsius corresponds to a corresponding demand load. A demand water temperature of 60 degrees Celsius corresponds to a corresponding demand load. The higher the demand water temperature, the greater the demand load.

[0087] Step 72: Generate a heating command based on the current demand load.

[0088] In some embodiments, a first heating command is generated in response to the current demand load being greater than the previous demand load.

[0089] In some embodiments, during the use of the water heater, there may be changes in demand load. Based on this, when the current demand load is greater than the previous demand load, a first heating command is generated.

[0090] In some embodiments, a second heating command is generated in response to the current demand load being less than the previous demand load.

[0091] In some embodiments, a third heating command is generated in response to the current demand load being equal to the previous demand load.

[0092] Step 73: In response to the heating command, generate a first damper control signal, or generate a first damper control signal and a first fan control signal.

[0093] In some embodiments, in response to a first heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated; the first damper control signal is used to instruct the drive device to increase the opening of the damper, and the first fan control signal is used to instruct the fan to increase the fan speed.

[0094] Since the first heating command is generated when the current demand load is greater than the previous demand load, it means that the water temperature needs to be increased. Based on this, it is necessary to increase the opening of the damper and / or increase the fan speed to accelerate the mixing of gas and air in the premix chamber and improve heating efficiency.

[0095] In some embodiments, in response to a second heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated; the first damper control signal is used to instruct the drive device to reduce the opening of the damper, and the first fan control signal is used to instruct the fan to reduce the fan speed.

[0096] Since the second heating command is generated when the current demand load is less than the previous demand load, it means that the water temperature needs to be reduced. Based on this, it is necessary to reduce the opening of the damper and / or reduce the fan speed to reduce the mixing of gas and air in the premixing chamber, reduce the heating efficiency, and thus achieve the effect of reducing the water temperature.

[0097] In some embodiments, in response to a third heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated. The first damper control signal is used to instruct the drive device to maintain the current opening of the damper, and the first fan control signal is used to instruct the fan to maintain the current fan speed.

[0098] Step 74: Send the first damper control signal to the drive device so that the drive device adjusts the opening of the damper and receives feedback from the position detection device on the actual opening of the damper; and / or send the first fan control signal to the fan so that the fan adjusts the fan speed according to the first fan control signal.

[0099] In some embodiments, after receiving feedback from the position detection device regarding the actual opening degree of the damper, a damper fault warning is triggered in response to the actual opening degree being less than or greater than the target opening degree, and the duration exceeding a preset duration. When the actual opening degree is less than or greater than the target opening degree, and the duration exceeds the preset duration, there may be an abnormality in the drive device or the position detection device. Therefore, triggering the damper fault warning allows the user to be aware of the abnormal damper opening, facilitating maintenance. The gas water heater can also be stopped during the warning.

[0100] In some embodiments, a fully premixed gas water heater may include a gas supply module, an air supply module, a control module, and a feedback loop.

[0101] Gas supply module: includes a gas valve and a flow sensor, used to measure and regulate gas flow.

[0102] Air supply module: includes a fan, an air intake chamber, and an active damper device. The active damper device is driven by a stepper motor or a servo motor and integrates a non-contact position sensor.

[0103] Control module: The controller receives flow signals, damper position feedback signals, and system operating parameters (such as outlet water temperature and combustion chamber pressure), and executes a closed-loop control algorithm.

[0104] Feedback loop: The position sensor monitors the damper opening in real time and generates a high-precision position feedback signal (accuracy ±0.5°), which is transmitted to the controller; the controller dynamically calculates the actual mixing ratio based on the load demand.

[0105] The workflow includes real-time monitoring, dynamic adjustment, and closed-loop correction.

[0106] Real-time monitoring is specifically reflected in the following: the position sensor continuously detects the damper opening, and the feedback signal is synchronously input to the controller along with the gas flow signal.

[0107] Dynamic adjustment is specifically reflected in the following: the controller, based on a preset target mixing ratio, uses an adaptive PID control algorithm to independently adjust the fan speed and damper opening.

[0108] When the load changes, the controller prioritizes adjusting the opening directly through the damper motor (response time ≤ 100ms) to achieve millisecond-level precise control of air intake.

[0109] Meanwhile, the fan speed serves as an auxiliary adjustment method to ensure airflow stability.

[0110] Closed-loop correction is specifically manifested in the following way: if the actual mixing ratio deviates from the target value (such as due to gas pressure fluctuations), the controller immediately corrects the damper opening, forming a "monitoring-calculation-adjustment" closed loop to eliminate the cumulative error of passive adjustment.

[0111] In this embodiment, an active damper drive is used instead of passive linkage, and the articulated movable flap that relies on airflow speed for drive in related technologies is abandoned. Instead, a motor-driven damper is used to eliminate the influence of mechanical friction and airflow disturbance on the opening degree, ensuring the absolute accuracy of the opening degree control.

[0112] It also provides a dual closed-loop position feedback mechanism, using position sensors to provide real-time opening data, which, together with the gas flow, forms a dual-parameter closed-loop control, unlike the single-variable wind speed linkage of related technologies, and solves the problem of lacking accurate position feedback.

[0113] It also features a dynamic decoupling adjustment strategy, decoupling the fan speed and damper opening control (in related technologies, the two are strongly coupled), and supports independent optimization. For example, under low load, the damper is adjusted first to maintain airtightness, and under high load, the fan is adjusted in tandem to improve response speed, thus achieving real-time dynamic adjustment across the entire operating range.

[0114] In addition, it achieves optimized design for minimum heat load. In the low opening range (such as less than 10%), the damper adopts a fine-tuning algorithm (stepper motor microstepping control) and combines position feedback correction to reduce the minimum heat load to less than 50% of the relevant technologies, significantly expanding the power coverage range (adjustment ratio up to 1:15).

[0115] In some embodiments, the scheduling between the modules described above is typically a timed task logic. For example, the control module generates a 2ms interrupt signal to perform phase control on the motor, then the drive unit and fan perform servo physical control, feeding back the current speed to the control module, and performing blockage detection within 200ms to achieve safety monitoring of the fan and damper, generating a blockage signal in case of an anomaly. The control module also generates a 10ms interrupt for status maintenance. Based on the status maintenance signal and the blockage signal, position feedback is performed, and servo physical control is performed again, thus achieving scheduling between the modules.

[0116] In some embodiments, a premixing chamber corresponds to a premixing chamber in the control module. The premixer drive control state machine typically has idle, running, braking, and fault states, representing the system being in an idle, running, braking, and fault state, respectively.

[0117] idle (idle state):

[0118] Definition: The system has not performed any active operation and is in a state of waiting for an event to be triggered.

[0119] Features: Typically in the initial state, requiring no processing of external input or execution of tasks.

[0120] Example: In motor control, the motor is in idle state when no start command is received.

[0121] running (running status):

[0122] Definition: The system is performing its main functions or tasks.

[0123] Features: Requires continuous processing of external events (such as sensor data) and maintenance of operating logic.

[0124] Example: After the motor starts, it enters the running state, continuously adjusting its speed or direction.

[0125] braking (braking state):

[0126] Definition: The intermediate state in which a system transitions from a running state to a stopped state.

[0127] Features: May involve deceleration, safety checks, or resource release operations.

[0128] Example: In case of an emergency stop, the motor first enters braking mode to complete deceleration, then switches to idle or fault mode.

[0129] fault (fault status):

[0130] Definition: When the system detects an anomaly or error, it needs to pause operation and address the issue.

[0131] Features: Typically triggers alarms, log entries, or automatic recovery mechanisms.

[0132] Example: When sensor data is abnormal, the system switches to fault state and attempts to restart or request manual intervention.

[0133] State transition example:

[0134] Taking motor control as an example:

[0135] idle → running: Startup command received.

[0136] running → braking: A stop request or fault was detected.

[0137] braking → idle: After braking is completed, the vehicle returns to idle.

[0138] running → fault: Sensor data error caused an anomaly.

[0139] In some embodiments, the premixer logic control state transitions involve positioning, preparation, movement, and error.

[0140] 1. Homing (Positioning):

[0141] The "homing" state typically refers to the premixer needing to return to a known, fixed position or "home" location before it can begin operation. This usually involves a series of sensor calibrations, zeroing the robotic arm, or returning to a safe position.

[0142] 2. Ready:

[0143] The Ready state indicates that the device has completed the initialization process (including homing) and is now ready to receive further operational commands. In this state, the premixer can perform further checks, such as confirming that all sensors are functioning correctly and ensuring there are no hardware faults. Once the Ready state is reached, the user or program can safely send movement or operational commands.

[0144] 3. Moving:

[0145] The Moving state refers to the premixer performing an action or moving to a designated position. In the Moving state, the system typically monitors various parameters during the motion process, such as speed, position, and load, to ensure the safety and accuracy of the motion.

[0146] 4. Error:

[0147] An "Error" status indicates that the system has detected a fault or anomaly and cannot continue normal operation. In this situation, the system will typically halt current operations and attempt to log error information (such as error codes) for troubleshooting and repair. Error handling may include attempting recovery (such as rehoming), warning the user, or automatically shutting down the device to prevent further damage.

[0148] Referring to Figure 8, which is a structural schematic diagram of an embodiment of the fully premixed gas water heater provided in this application, the fully premixed gas water heater 100 includes: a premixing chamber 10, a fan 20, a damper 30, a drive device 40, a position detection device 50, a processor 60, and a memory 70. The drive device 40 is used to directly drive the damper 30; the position detection device 50 is used to detect the opening degree of the damper 30; the processor 60 is connected to the drive device 40, the position detection device 50, and the fan 20; the memory 70 is connected to the processor 60 and is used to store computer programs; the processor 60 is used to execute the computer programs to implement the following methods:

[0149] In response to a heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated; the first damper control signal is sent to a drive device to adjust the opening of the damper, and the actual opening of the damper is received from a position detection device; and / or, a first fan control signal is sent to a fan to adjust the fan speed according to the first fan control signal.

[0150] In some embodiments, after receiving feedback from the position detection device on the actual opening degree of the damper, the processor 60 is further configured to execute a computer program to implement the following methods: adjusting the first damper control signal according to the actual opening degree to obtain a second damper control signal, and / or adjusting the first fan control signal to obtain a second fan control signal; sending the second damper control signal to the damper drive device, and / or sending the second fan control signal to the fan.

[0151] In some embodiments, the processor 60 is further configured to execute a computer program to implement the following methods: acquiring a target opening degree corresponding to a first fan control signal; adjusting the first fan control signal to obtain a second fan control signal in response to an actual opening degree greater than the target opening degree; wherein the second fan control signal is used to instruct the fan to reduce its speed; and / or adjusting a first damper control signal to obtain a second damper control signal; the second damper control signal is used to instruct the drive device to reduce the damper opening degree; adjusting the first fan control signal to obtain a second fan control signal in response to an actual opening degree less than the target opening degree; wherein the second fan control signal is used to instruct the fan to increase its speed; and / or adjusting the first damper control signal to obtain a second damper control signal; the second damper control signal is used to instruct the drive device to increase the damper opening degree; and maintaining the first damper control signal and the first fan control signal in response to an actual opening degree equal to the target opening degree.

[0152] In some embodiments, the processor 60 is further configured to execute a computer program to implement the following methods: obtaining the current demand load; generating a heating command based on the current demand load; and generating a first damper control signal in response to the heating command, or generating both the first damper control signal and the first fan control signal.

[0153] In some embodiments, the processor 60 is further configured to execute a computer program to implement the following method: generating a first heating command in response to a current demand load being greater than a previous demand load; generating a second heating command in response to a current demand load being less than a previous demand load; generating a first heating command in response to a current demand load being equal to a previous demand load; and generating a first damper control signal, or generating a first damper control signal and a first fan control signal, in response to the heating command, including: generating a first damper control signal, or generating a first damper control signal and a first fan control signal, in response to the first heating command; the first damper control signal being used to indicate... The drive unit increases the opening of the damper, and the first fan control signal is used to instruct the fan to increase the fan speed; in response to the second heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated; the first damper control signal is used to instruct the drive unit to decrease the opening of the damper, and the first fan control signal is used to instruct the fan to decrease the fan speed; in response to the third heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated, the first damper control signal is used to instruct the drive unit to maintain the current opening of the damper, and the first fan control signal is used to instruct the fan to maintain the current fan speed.

[0154] In some embodiments, the processor 60 is further configured to execute a computer program to implement the following methods: acquiring a current gas flow signal; adjusting a first damper control signal to obtain a second damper control signal based on the current gas flow signal and the actual opening degree; and / or adjusting a first fan control signal to obtain a second fan control signal.

[0155] In some embodiments, the processor 60 is further configured to execute a computer program to implement the following method: determining an actual mixing ratio based on the current gas flow signal and the actual opening degree; the actual mixing ratio being the mixing ratio of gas and air; adjusting a first damper control signal to obtain a second damper control signal based on the actual mixing ratio, and / or adjusting a first fan control signal to obtain a second fan control signal.

[0156] In some embodiments, after receiving feedback from the position detection device on the actual opening of the damper, the processor 60 is further configured to execute a computer program to implement the following method: in response to the actual opening being less than or greater than the target opening and lasting for a duration longer than a preset duration, triggering a damper fault warning.

[0157] In some embodiments, the processor 60 is also configured to execute a computer program to implement the method of any embodiment of this application.

[0158] Referring to Figure 9, which is a schematic diagram of an embodiment of a computer-readable storage medium provided in this application, the computer-readable storage medium 90 is used to store a computer program 91. When executed by a processor, the computer program 91 is used to implement the following method:

[0159] In response to a heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated; the first damper control signal is sent to a drive device to adjust the opening of the damper, and the actual opening of the damper is received from a position detection device; and / or, a first fan control signal is sent to a fan to adjust the fan speed according to the first fan control signal.

[0160] In some embodiments, after receiving feedback from the position detection device on the actual opening degree of the damper, the computer program 91, when executed by the processor, is further used to: adjust the first damper control signal according to the actual opening degree to obtain a second damper control signal, and / or adjust the first fan control signal to obtain a second fan control signal; send the second damper control signal to the damper drive device, and / or send the second fan control signal to the fan.

[0161] In some embodiments, when executed by a processor, the computer program 91 is further configured to: acquire a target opening degree corresponding to a first fan control signal; adjust the first fan control signal to obtain a second fan control signal in response to an actual opening degree greater than the target opening degree; wherein the second fan control signal is used to instruct the fan to reduce its speed; and / or adjust the first damper control signal to obtain a second damper control signal; the second damper control signal is used to instruct the drive device to reduce the damper opening degree; adjust the first fan control signal to obtain a second fan control signal in response to an actual opening degree less than the target opening degree; wherein the second fan control signal is used to instruct the fan to increase its speed; and / or adjust the first damper control signal to obtain a second damper control signal; the second damper control signal is used to instruct the drive device to increase the damper opening degree; and maintain the first damper control signal and the first fan control signal in response to an actual opening degree equal to the target opening degree.

[0162] In some embodiments, when the computer program 91 is executed by the processor, it is also used to: obtain the current demand load; generate a heating command based on the current demand load; and generate a first damper control signal in response to the heating command, or generate a first damper control signal and a first fan control signal.

[0163] In some embodiments, when executed by a processor, the computer program 91 is further configured to: generate a first heating command in response to a current demand load being greater than a previous demand load; generate a second heating command in response to a current demand load being less than a previous demand load; generate a first heating command in response to a current demand load being equal to a previous demand load; and generate a first damper control signal, or generate a first damper control signal and a first fan control signal, in response to the heating command, including: generating a first damper control signal, or generating a first damper control signal and a first fan control signal, in response to the first heating command; the first damper control signal is used to indicate... The drive unit increases the opening of the damper, and the first fan control signal is used to instruct the fan to increase the fan speed; in response to the second heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated; the first damper control signal is used to instruct the drive unit to decrease the opening of the damper, and the first fan control signal is used to instruct the fan to decrease the fan speed; in response to the third heating command, a first damper control signal is generated, or a first damper control signal and a first fan control signal are generated, the first damper control signal is used to instruct the drive unit to maintain the current opening of the damper, and the first fan control signal is used to instruct the fan to maintain the current fan speed.

[0164] In some embodiments, when the computer program 91 is executed by the processor, it is also used to: acquire the current gas flow signal; adjust the first damper control signal according to the current gas flow signal and the actual opening degree to obtain the second damper control signal, and / or adjust the first fan control signal to obtain the second fan control signal.

[0165] In some embodiments, when the computer program 91 is executed by the processor, it is also used to: determine the actual mixing ratio based on the current gas flow signal and the actual opening degree; the mixing ratio is the mixing ratio of gas and air; adjust the first damper control signal according to the actual mixing ratio to obtain the second damper control signal, and / or adjust the first fan control signal to obtain the second fan control signal.

[0166] In some embodiments, after receiving feedback from the position detection device on the actual opening degree of the damper, the computer program 91, when executed by the processor, is further configured to implement the following method: in response to the actual opening degree being less than or greater than the target opening degree and the duration being greater than a preset duration, triggering a damper fault warning.

[0167] In some embodiments, when executed by a processor, computer program 91 is also used to implement the method of any embodiment of this application.

[0168] In summary, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, include a premixed gas water heater comprising a premixing chamber, a fan, a damper, a drive device, and a position detection device. The drive device directly drives the damper, and the position detection device detects the opening degree of the damper. During the heating process, the drive device directly drives the damper, which, compared to fixed dampers and passively controlled dampers, improves the control efficiency of the damper and accelerates the time for air to enter the premixing chamber, thereby improving heating efficiency. Furthermore, the position detection device provides feedback on the actual opening degree of the damper, facilitating fine adjustments to the opening degree and enabling precise control of the damper opening. This allows for precise control of the gas-air mixing ratio in the premixing chamber, which helps to further reduce the minimum heat load of the fully premixed gas water heater and meet more hot water usage needs.

[0169] Furthermore, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, can improve the accuracy of mixing ratio control. For example, through position feedback closed loop, the mixing ratio error can be controlled within ±2% (related technical error ≥5%), resulting in more complete combustion and a reduction of harmful gas emissions by more than 30%.

[0170] Furthermore, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, enable highly stable combustion efficiency, such as a dynamic adjustment response time shortened to within 0.5 seconds, adapting to sudden load changes, and a thermal efficiency fluctuation range of ≤±1.5% (related technologies ≥±3%).

[0171] Furthermore, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, have real-time dynamic adjustment capabilities, such as supporting millisecond-level opening adjustment, which meets the rapid start-stop and variable flow requirements of smart water heaters, and significantly improves the user experience.

[0172] Furthermore, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, can achieve precise position feedback. For example, the position sensor provides continuous opening data, and the controller can record historical trajectories and predict faults, thus avoiding the risk of gas leakage (such as automatic alarm when the damper is stuck).

[0173] Furthermore, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, can maximize the power coverage range, such as reducing the minimum heat load to 3.5kW (approximately 5.2kW in related technologies) and expanding the adjustment ratio to 1:15, covering the needs of all scenarios such as household bathing and kitchen water use.

[0174] Furthermore, the fully premixed gas water heater and its control method, as well as the computer-readable storage medium provided in this application, can simplify the structure and improve reliability. For example, it eliminates the complex hinged flap mechanical structure in related technologies, reduces wear points, and extends the system life by more than 20%.

[0175] In the several embodiments provided in this application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device 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 system, or some features may be ignored or not executed.

[0176] If the integrated units in the other embodiments described above are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processing circuit component (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.

[0177] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A control method for a fully premixed gas water heater, characterized in that, The fully premixed gas water heater includes a premixing chamber, a fan, a damper, a drive device, and a position detection device. The drive device directly drives the damper, and the position detection device detects the opening degree of the damper. The control method includes: acquiring the current demand load; generating a heating command based on the current demand load; generating a first damper control signal and a first fan control signal in response to the heating command; sending the first damper control signal to the drive device to adjust the opening degree of the damper, and receiving feedback from the position detection device on the actual opening degree of the damper; and sending the first fan control signal... The signal is sent to the fan so that the fan adjusts its speed according to the first fan control signal; wherein the first damper control signal is sent before the first fan control signal; after receiving feedback from the position detection device on the actual opening of the damper, the first damper control signal is adjusted according to the actual opening to obtain a second damper control signal, and / or the first fan control signal is adjusted to obtain a second fan control signal; the second damper control signal is sent to the damper drive device, and / or the second fan control signal is sent to the fan; the additional load is generated according to the current demand load. A heating command includes: generating a first heating command in response to the current demand load being greater than the previous demand load; generating a second heating command in response to the current demand load being less than the previous demand load; and generating a third heating command in response to the current demand load being equal to the previous demand load. The step of generating a first damper control signal and a first fan control signal in response to the heating command includes: generating a first damper control signal and a first fan control signal in response to the first heating command; the first damper control signal instructs the drive device to increase the opening of the damper, and the first fan control signal instructs the fan to increase the fan speed; generating a first damper control signal and a first fan control signal in response to the second heating command; the first damper control signal instructs the drive device to decrease the opening of the damper, and the first fan control signal instructs the fan to decrease the fan speed; generating a first damper control signal and a first fan control signal in response to the third heating command, the first damper control signal instructing the drive device to maintain the current opening of the damper, and the first fan control signal instructing the fan to maintain the current fan speed.

2. The control method according to claim 1, characterized in that, The step of adjusting the first damper control signal to obtain a second damper control signal and / or adjusting the first fan control signal to obtain a second fan control signal based on the actual opening degree includes: acquiring a target opening degree corresponding to the first fan control signal; adjusting the first fan control signal to obtain a second fan control signal in response to the actual opening degree being greater than the target opening degree; wherein the second fan control signal is used to instruct the fan to reduce the fan speed; and / or adjusting the first damper control signal to obtain a second damper control signal; the second damper control signal is used to instruct the drive device to reduce the damper opening degree; adjusting the first fan control signal to obtain a second fan control signal in response to the actual opening degree being less than the target opening degree; wherein the second fan control signal is used to instruct the fan to increase the fan speed; and / or adjusting the first damper control signal to obtain a second damper control signal; the second damper control signal is used to instruct the drive device to increase the damper opening degree; and maintaining the first damper control signal and the first fan control signal in response to the actual opening degree being equal to the target opening degree.

3. The control method according to claim 1, characterized in that, The step of adjusting the first damper control signal to obtain a second damper control signal and / or adjusting the first fan control signal to obtain a second fan control signal based on the actual opening degree includes: acquiring a current gas flow signal; adjusting the first damper control signal to obtain a second damper control signal based on the current gas flow signal and the actual opening degree, and / or adjusting the first fan control signal to obtain a second fan control signal.

4. The control method according to claim 3, characterized in that, The step of adjusting the first damper control signal to obtain a second damper control signal and / or adjusting the first fan control signal to obtain a second fan control signal based on the current gas flow signal and the actual opening degree includes: determining an actual mixing ratio based on the current gas flow signal and the actual opening degree; the actual mixing ratio being the mixing ratio of gas and air; adjusting the first damper control signal to obtain a second damper control signal based on the actual mixing ratio; and / or adjusting the first fan control signal to obtain a second fan control signal.

5. The control method according to any one of claims 1-4, characterized in that, After receiving feedback from the position detection device on the actual opening degree of the damper, the method further includes: triggering a damper fault warning in response to the actual opening degree being less than or greater than the target opening degree and lasting for a duration greater than a preset duration.

6. A fully premixed gas water heater, characterized in that, The fully premixed gas water heater includes: a premixing chamber; a fan; a damper; a drive device for directly driving the damper; a position detection device for detecting the opening degree of the damper; a processor connected to the drive device, the position detection device, and the fan; and a memory connected to the processor for storing a computer program. The processor executes the computer program to implement the method as described in any one of claims 1-5.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store a computer program, which, when executed by a processor, is used to implement the method as described in any one of claims 1-5.

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