Gas water heater, control method and device thereof and computer readable storage medium

Abstract

The invention discloses a gas water heater, a control method and device of the gas water heater and a computer readable storage medium. The gas water heater comprises a preheating burner and a high-temperature air burner, wherein the high-temperature air burner is connected with high-temperature flue gas formed by burning of the preheating burner to generate high-temperature air burning; the control method of the gas water heater comprises the following steps that the water inlet temperature and the water inlet flow of the gas water heater are detected; according to the water inlet temperature, the water inlet flow and the target temperature, the heat load needed by the gas water heater for heating the inlet water from the water inlet temperature to the target temperature is calculated; and matching the calculated heat load with the heat load interval ranges in the first heating mode and the second heating mode, and controlling the preheating burner to work when the heat load is in the heat load interval range corresponding to the first heating mode, and controlling the preheating burner and the high-temperature air burner to work in the corresponding heat load interval range in the second heating mode. Energy conservation and emission reduction of the water heater are achieved, and emission of pollutants (CO and NOx) is reduced.

Description

[0001] This application is a divisional case based on the Chinese patent application "filed on January 14, 2021, with application number 202110052740.X and named "Gas Water Heater and Its Control Method, Device and Computer-readable Storage Medium", and all its contents are incorporated into this application by reference. Technical Field

[0002] The present invention relates to the technical field of electronic circuits, and in particular to a gas water heater and a control method, device and computer-readable storage medium thereof. Background Art

[0003] High temperature air combustion is called "mild and deep low oxygen dilution combustion", or gentle combustion for short. It is a new type of combustion method, also known as MILD combustion. The main characteristics of this combustion are: the chemical reaction mainly occurs in a high temperature and low oxygen environment, the reactant temperature is higher than its auto-ignition temperature, and the maximum temperature rise during the combustion process is lower than its auto-ignition temperature. The oxygen volume fraction is diluted by the combustion products to an extremely low concentration, usually 3% to 10%. Compared with conventional combustion, in this combustion state, the pyrolysis of the fuel is suppressed, the flame thickness becomes thicker, and the flame front disappears, so that the temperature of the entire furnace is very uniform during this combustion, and the emissions of pollutants NOx and CO are greatly reduced.

[0004] Although high-temperature air combustion has many advantages as mentioned above, it does not automatically select the appropriate combustion mode according to the heat load, which easily leads to problems such as high energy consumption and low efficiency of gas water heaters. Summary of the invention

[0005] The main purpose of the present invention is to provide a gas water heater and its control method, device and computer-readable storage medium, aiming to achieve energy saving and emission reduction of the water heater, and reduce the emission of pollutants (CO and NOx).

[0006] To achieve the above object, the present invention provides a gas water heater control method, the gas water heater comprising a preheating burner and a high-temperature air burner connected to the high-temperature flue gas formed by the preheating burner to generate high-temperature air combustion, the gas water heater control method comprising the following steps:

[0007] Detecting the water inlet temperature and water inlet flow rate of the gas water heater;

[0008] Calculating the heat load required for the gas water heater to heat the inlet water from the inlet water temperature to the target temperature according to the inlet water temperature, the inlet water flow rate and the target temperature; and

[0009] The calculated heat load is matched with the heat load interval range under the first heating mode and the second heating mode respectively to heat the inlet water from the inlet water temperature to the target temperature. When the calculated heat load is in the heat load interval range corresponding to the first heating mode, the preheating burner is controlled to operate; when the calculated heat load is in the heat load interval range corresponding to the second heating mode, the preheating burner and the high-temperature air burner are controlled to operate simultaneously; wherein, in the first heating mode and the second heating mode, the gas water heater can provide a heat load in the corresponding interval range.

[0010] Optionally, when the calculated heat load is within a heat load interval corresponding to the first heating mode, the preheating burner is controlled to operate; when the calculated heat load is within a heat load interval corresponding to the second heating mode, the step of controlling the preheating burner and the high-temperature air burner to operate simultaneously specifically includes:

[0011] When the calculated heat load is within the heat load interval corresponding to the first heating mode, controlling the preheating burner to perform heating according to the first heating mode;

[0012] When the calculated heat load is within the heat load interval corresponding to the second heating mode, the preheating burner and the high-temperature air burner are controlled to perform heating work according to the second heating mode at the same time.

[0013] Optionally, in the first heating mode and the second heating mode, the gas water heater can provide a heat load in a corresponding range, and the heat load in the corresponding range provided includes a first preset heat load, which is greater than or equal to the minimum output heat load of the high-temperature air burner and less than the maximum output heat load of the preheating burner;

[0014] Alternatively, the first preset heat load is greater than the minimum output heat load of the high temperature air burner and less than or equal to the maximum output heat load of the preheating burner.

[0015] Optionally, in the first heating mode and the second heating mode, the gas water heater can provide a heat load in a corresponding interval range, and the heat load in the corresponding interval range provided includes a first preset heat load. When the required heat load is less than the first preset heat load and the first heating mode is selected for heating, if the required heat load gradually increases and is less than the maximum load Q1max of the preheating burner, the preheating burner is continuously controlled to operate until the required heat load is greater than the maximum load Q1max of the preheating burner.

[0016] Optionally, in the first heating mode and the second heating mode, the gas water heater can provide a heat load in a corresponding interval range, and the heat load in the corresponding interval range provided includes a first preset heat load. When the required heat load is greater than or equal to the first preset heat load and the second heating mode is selected for heating, if the required heat load gradually decreases and is greater than the minimum load Q2min of the high-temperature air burner, the high-temperature air burner is continuously controlled to operate until the required heat load is less than the minimum load Q2min of the high-temperature air burner.

[0017] Optionally, in the second heating mode, the step of controlling the operation of the preheating burner and the high temperature air burner specifically includes:

[0018] Controlling the preheating burner to start up to burn the formed high-temperature flue gas; and,

[0019] The high-temperature air burner is controlled to operate, and is connected to the preheating burner to cause high-temperature air combustion.

[0020] Optionally, after the step of calculating the heat load required for the gas water heater to heat the inlet water from the inlet water temperature to the target temperature according to the inlet water temperature, the inlet water flow rate and the target temperature, the gas water heater control method further comprises the following steps:

[0021] The opening of the gas valve of the gas water heater is adjusted according to the heat load to adjust the gas flow output to the combustion chamber where the preheating burner and the high-temperature air burner are located.

[0022] Optionally, after the step of calculating, according to the inlet water temperature, the inlet water flow rate and the target temperature, that the gas water heater heats the inlet water from the inlet water temperature to the target temperature, the gas water heater control method further comprises the following steps:

[0023] The speed of the fan of the gas water heater is adjusted according to the heat load to adjust the air flow output to the combustion chamber where the preheating burner and the high-temperature air burner are located.

[0024] Optionally, the gas water heater control method further comprises the following steps:

[0025] Obtaining the outlet water temperature of the gas water heater; and,

[0026] When the outlet water temperature reaches the target temperature, the heating modes of the preheating burner and the high-temperature air burner are updated according to the heat load, and the operations of the preheating burner and the high-temperature air burner are controlled.

[0027] Optionally, the heat load is calculated according to the following formula:

[0028] Q=C*M*(T2-T1)

[0029] Among them, Q is the heat load; C is the specific heat capacity of water; M is the mass of water and is obtained according to the water inlet flow rate; T2 is the target temperature; and T1 is the water inlet temperature.

[0030] The present invention also provides a gas water heater control device, the gas water heater control device comprising a processor, a memory, and a gas water heater control program stored in the memory and executable on the processor, wherein the gas water heater control program implements the steps of the gas water heater control method described above when executed by the processor; the gas water heater control method comprises the following steps:

[0031] Detecting the water inlet temperature and water inlet flow rate of the gas water heater;

[0032] Calculating the heat load required for the gas water heater to heat the inlet water from the inlet water temperature to the target temperature according to the inlet water temperature, the inlet water flow rate and the target temperature; and

[0033] According to the heat load, the first heating mode or the second heating mode is selected to perform heating work to heat the inlet water from the inlet water temperature to the target temperature. In the first heating mode, the preheating burner is controlled to work, and in the second heating mode, the preheating burner and the high-temperature air burner are controlled to work.

[0034] The present invention further provides a gas water heater, which is provided with a cold water inlet pipe and a hot water outlet pipe, and the gas water heater comprises:

[0035] a casing, the interior of which forms a combustion chamber;

[0036] A high temperature air burner installed in the combustion chamber;

[0037] A preheating burner installed in the combustion chamber and arranged adjacent to the high-temperature air burner;

[0038] a heat exchanger, one end of which is connected to the cold water inlet pipe and the other end of which is connected to the hot water outlet pipe, the heat exchanger being used to absorb the heat generated by the combustion of the preheating burner and the combustion of the high-temperature air burner and to exchange the absorbed heat with the water inside the heat exchanger; and,

[0039] The gas water heater control device as described above is used to adjust the heating modes of the preheating burner and the high-temperature air burner according to the acquired heat load to heat the inlet water from the inlet water temperature to the target temperature.

[0040] The present invention further provides a computer-readable storage medium, on which a gas water heater control program is stored. When the gas water heater control program is executed by a processor, the steps of the gas water heater control method described above are implemented.

[0041] The gas water heater control method of the present invention detects the water inlet temperature and water inlet flow of the gas water heater, calculates the gas water heater to heat the water inlet from the water inlet temperature to the target temperature according to the water inlet temperature, the water inlet flow and the target temperature; and selects the first heating mode or the second heating mode to perform heating according to the heat load, so that the heat exchanger absorbs the heat generated by the combustion of the preheating burner and the combustion of the high-temperature air burner and performs heat exchange with the water inside the heat exchanger, so as to heat the water inlet from the water inlet temperature to the target temperature. In the first heating mode, the preheating burner is controlled to work, and in the second heating mode, the preheating burner and the high-temperature air burner are controlled to work. In this way, according to actual application, the preheating burner is controlled to work in a small load state, and the preheating burner and the high-temperature air burner are controlled to work at the same time in a large load state. The present invention solves the problem that the gas water heater adopts high-temperature air combustion at low load, resulting in a long preheating time and high energy consumption, so that the gas water heater cannot effectively respond to user needs. Or when the user requires a high preheating temperature, only ordinary combustion is used under high load conditions, resulting in the generation of more pollutants such as NOx and CO. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0043] Figure 1 A schematic diagram of a flow chart of an embodiment of a gas water heater control method of the present invention;

[0044] Figure 2 for Figure 1 A detailed flow chart of step 300 in an embodiment;

[0045] Figure 3 A flow chart of another embodiment of a gas water heater control method of the present invention;

[0046] Figure 4 A flow chart of another embodiment of a gas water heater control method of the present invention;

[0047] Figure 5A flow chart of another embodiment of a gas water heater control method of the present invention;

[0048] Figure 6 A schematic diagram of the terminal structure of the hardware operating environment of the gas water heater control device involved in the embodiment of the present invention;

[0049] Figure 7 It is a structural schematic diagram of an embodiment of a gas water heater of the present invention;

[0050] Figure 8 It is a schematic diagram of the relationship between the first heating mode, the second heating mode and the heat load.

[0051] Description of Figure Numbers:

[0052]

[0053]

[0054] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0057] The invention provides a gas water heater control method.

[0058] The gas water heater comprises a preheating burner and a high temperature air burner which is connected to the high temperature flue gas formed by the combustion of the preheating burner to generate high temperature air combustion. High temperature air combustion (high temperature air combustion) is called "mild and deep low oxygen dilution combustion", or gentle combustion for short, which is a new type of combustion mode, also known as MILD combustion. The main characteristics of this combustion are: the chemical reaction mainly occurs in a high temperature and low oxygen environment, the temperature of the reactants is higher than their natural temperature, and the maximum temperature rise during the combustion process is lower than its natural temperature, and the oxygen volume fraction is diluted by the combustion products to an extremely low concentration, usually 3% to 5%. Compared with conventional combustion, in this combustion state, the pyrolysis of the fuel is suppressed, the flame thickness becomes thicker, and the flame front disappears. As a result, the temperature of the entire furnace is very uniform during this combustion, and the emissions of pollutants NOx and CO are greatly reduced. High temperature air combustion is a volumetric combustion or diffuse combustion, which is characterized by low reaction rate, low local heat release, uniform heat flux distribution, low combustion peak temperature and extremely low noise. Compared with the traditional small-area local high-temperature combustion, the reaction of this combustion is carried out in a large area or even the entire furnace, and the flame front disappears; the generation of pollutants such as NOx and CO is significantly reduced; the overall temperature of the furnace is increased, and the radiation heat transfer is enhanced. High-temperature preheating of air and high-speed jets are the main ways to achieve high-temperature air combustion; entraining high-temperature flue gas and diluting the combustion air jet are the technical keys to maintain high-temperature air combustion; the important condition for establishing high-temperature air combustion is that the oxygen concentration at any position in the furnace after the jet mixing zone is less than 5% to 10%, and the temperature is higher than the auto-ignition point of the fuel. This requires the strong internal circulation of high-temperature flue gas (exhaust gas rich in N2 and CO2) in the furnace to dilute the reactants.

[0059] It is understandable that the gas water heater using high-temperature air combustion is provided with a shell, which is formed with a preheating combustion chamber and a high-temperature air combustion chamber in sequence, and a smoke exhaust port is also provided on the shell, and the preheating burner is installed in the preheating combustion chamber; the high-temperature air burner is installed in the high-temperature air combustion chamber, and the gas water heater is also provided with a heat exchanger, which is located between the smoke exhaust port and the high-temperature air combustion chamber; the shell is provided with a water inlet pipe for introducing water into the gas water heater, a hot water outlet pipe for providing hot water to the outside, and a smoke exhaust pipe connected to the smoke exhaust port, a gas intake pipeline connected to the gas, and an intake valve can all adopt existing ones, which will not be described in detail here. Among them, the preheating burner is used to heat the gas in the high-temperature air combustion chamber. The preheating burner can adopt a honeycomb structure that can effectively prevent backfire during the combustion process. For example, the gas water heater also includes an igniter, which is used to ignite the gas injected from the preheating burner. A gas injection pipe is provided in the high-temperature air burner, which has a gas inlet and a gas outlet. The gas outlet of the gas injection pipe is arranged in the high-temperature air combustion chamber to inject gas into the high-temperature combustion chamber so that a high-temperature air combustion reaction occurs in the high-temperature air combustion chamber.

[0060] When the gas water heater is started, the preheating burner can be controlled to burn, and the gas and air entering the preheating combustion chamber are ignited by the preheating burner, so that the mixed gas of gas and air burns to heat the air in the preheating combustion chamber to form high-temperature flue gas. It can be understood that by controlling the heating temperature, the air in the preheating combustion chamber can be heated to the target temperature, that is, the target temperature mentioned above, so that the high-temperature preheating of the air is achieved. After the high-temperature gas after high-temperature preheating is sent to the high-temperature air combustion chamber, the gas is sprayed into the high-temperature air combustion chamber, the gas is combined with the high-temperature gas, and the high-temperature gas ignites the gas to achieve MILD combustion in the high-temperature air combustion chamber. It can be understood that when the preheating burner is working and the air in the preheating combustion chamber is heated, heat exchange with the heat exchanger can also be achieved.

[0061] It can also be understood that the gas water heater can have a preheating function, which can preheat the water in the circulation pipeline, so as to achieve the purpose of getting hot water when opening the valve when using water, that is, the zero cold water gas water heater can realize hot water that can be used immediately. Specifically, when the preheating function is started, the built-in circulation pump set in the zero cold water gas water heater is operated to pump the water stored in the hot water outlet pipe and return pipe outside the zero cold water gas water heater back to the zero cold water gas water heater for preheating, forming a preheating circulation pipeline to achieve preheating. The zero cold water function can be applied to bathing scenes, and can also be applied to zero cold water scenes for washing. Of course, the preheating function can be started with one button according to user needs, or the user can set the preheating time, preheating temperature, etc. by himself. As the user's needs are different, the preheating temperature is different, and the required heat load is also different. In addition, during the heating process, as the heating time increases, the required heat load also changes. Alternatively, the water pressure, water flow, etc. may also change depending on the user's water use time. Alternatively, the water inlet temperature will also be different depending on the season in which the water heater is used. If the control of the gas water heater is not changed according to the application scenario, for example, if the user requires a low preheating temperature, high-temperature air combustion will be used even in a small load state, which will result in a long preheating time and high energy consumption, making the gas water heater unable to effectively respond to user needs. If the user requires a high preheating temperature, only ordinary combustion will be used in a large load state, which will result in the generation of more pollutants such as NOx and CO.

[0062] To solve the above problems, refer to Figure 1 In one embodiment of the present invention, the gas water heater control method comprises the following steps:

[0063] Step S100, detecting the water inlet temperature and water inlet flow rate of the gas water heater;

[0064] In this embodiment, the inlet water temperature can be detected by a temperature sensor disposed in the water inlet pipe, and the inlet water flow rate can be calculated by a flow meter disposed in the water inlet pipe.

[0065] Step S200, calculating the heat load required for the gas water heater to heat the inlet water from the inlet water temperature to the target temperature according to the inlet water temperature, the inlet water flow rate and the target temperature;

[0066] Specifically, the heat load is calculated according to the following formula:

[0067] Q=C*M*(T2-T1)

[0068] Among them, Q is the heat load; C is the specific heat capacity of water; M is the mass of water and is obtained according to the water inlet flow rate; T2 is the target temperature; and T1 is the water inlet temperature.

[0069] In this embodiment, the inlet water temperature t1 and the inlet water flow rate of the gas water heater are first detected, and the water mass M is obtained according to the detected inlet water flow rate. Then, the inlet water temperature t1, the obtained water mass M and the target temperature T2 are substituted into the above formula to calculate the heat load Q required for the gas water heater to heat the inlet water from the inlet water temperature to the user-set temperature, that is, the target temperature. Then, the heating mode of the gas water heater is determined according to the heat load Q. In the first heating mode and the second heating mode, the preheating burner and the high-temperature air burner can provide a certain range of heat loads. When the calculated heat load is in the first heating mode, the preheating burner is controlled to work. When it is in the second heating mode, the preheating burner and the high-temperature air burner are controlled to work simultaneously.

[0070] Step S300, according to the heat load, select the first heating mode or the second heating mode to perform heating work, so as to heat the inlet water from the inlet water temperature to the target temperature, in the first heating mode, control the preheating burner to work, in the second heating mode, control the preheating burner and the high-temperature air burner to work. And, when controlling the preheating burner and the high-temperature air burner to work, specifically, control the preheating burner to start, so as to burn the high-temperature flue gas formed; and control the high-temperature air burner to work, and connect the preheating burner to generate high-temperature air combustion.

[0071] In this embodiment, when the gas water heater is started, in the first heating mode, only the preheating burner is controlled to work, and the high-temperature air burner is not working at this time. The preheating burner is controlled to burn, and the gas and air entering the preheating combustion chamber are ignited by the preheating burner, so that the mixed gas mixed with gas and air is burned to heat the air in the preheating combustion chamber, and the high-temperature flue gas formed is heat-exchanged with the heat exchanger, thereby meeting the heat load demand under the current user demand. It can be understood that by controlling the heating temperature, the air in the preheating combustion chamber can be heated to the target temperature, which is the temperature required to add the cold water in the heat exchanger to the user's water use, that is, the user-set temperature. In this process, the preheating burner is used to burn the air and gas entering the preheating combustion chamber, and the heat generated is used for heat exchange with the heat exchanger.

[0072] In the second heating mode, the preheating burner and the high-temperature air burner work at the same time, and the combustion of the preheating burner is controlled. The gas and air entering the preheating combustion chamber are ignited by the preheating burner, so that the mixed gas of gas and air burns to heat the air in the preheating combustion chamber to form high-temperature flue gas. After the high-temperature gas after high-temperature preheating is sent to the high-temperature air combustion chamber, the gas is sprayed into the high-temperature air combustion chamber, the gas is combined with the high-temperature gas, and the high-temperature gas ignites the gas to achieve MILD combustion in the high-temperature air combustion chamber. The heat generated by the combustion is heat-exchanged with the heat exchanger, thereby meeting the heat load requirements under the current user water demand. In this process, the preheating burner is used to burn the air and gas entering the preheating combustion chamber, and the heat generated is used for heat exchange with the heat exchanger. After being input into the high-temperature air combustion chamber, MILD combustion is completed. At the same time, the heat generated by the preheating combustion can also be heat-exchanged with the heat exchanger. In practical applications, a valve can be set at the gas inlet of the high-temperature air combustion chamber. In the second heating mode, the valve is controlled to open to supply gas to the high-temperature air combustion chamber, and in the first heating mode, the valve is controlled to close to stop supplying gas to the high-temperature air combustion chamber. At this time, MILD combustion will not be carried out in the high-temperature air combustion chamber. In this way, the high-temperature air burner can be controlled.

[0073] The gas water heater control method of the present invention detects the water inlet temperature and water inlet flow of the gas water heater, calculates the gas water heater to heat the water inlet from the water inlet temperature to the target temperature according to the water inlet temperature, the water inlet flow and the target temperature; and selects the first heating mode or the second heating mode to perform heating according to the heat load, so that the heat exchanger absorbs the heat generated by the combustion of the preheating burner and the combustion of the high-temperature air burner and performs heat exchange with the water inside the heat exchanger, so as to heat the water inlet from the water inlet temperature to the target temperature. In the first heating mode, the preheating burner is controlled to work, and in the second heating mode, the preheating burner and the high-temperature air burner are controlled to work. In this way, according to actual application, the preheating burner is controlled to work in a small load state, and the preheating burner and the high-temperature air burner are controlled to work at the same time in a large load state. The present invention solves the problem that the gas water heater adopts high-temperature air combustion at low load, resulting in a long preheating time and high energy consumption, so that the gas water heater cannot effectively respond to user needs. Or when the user requires a high preheating temperature, only ordinary combustion is used under high load conditions, resulting in the generation of more pollutants such as NOx and CO.

[0074] Reference Figure 2 In one embodiment, the step of selecting the first heating mode or the second heating mode to perform heating according to the heat load specifically includes:

[0075] Step S310: When the required heat load is less than the first preset heat load, select the first heating mode to perform heating;

[0076] Step S320: When the required heat load is greater than or equal to the first preset heat load, select the second heating mode to perform heating.

[0077] Wherein, the first preset heat load is greater than or equal to the minimum output heat load of the high-temperature air burner, and less than or equal to the maximum output heat load of the preheating burner.

[0078] In this embodiment, in the first heating mode, only the preheating burner works, and the heat load generated is limited and can meet the needs of low heat load. In the second heating mode, the preheating burner and the high-temperature air burner work at the same time. Under the action of the preheating burner and the high-temperature air burner, part of the high-temperature flue gas (waste gas rich in N2 and CO2) can be intensively circulated internally in the high-temperature air combustion chamber to dilute the reactants, and then the input fuel gas and air are fully diluted to form a lower oxygen concentration, reduce the combustion reaction rate, and maintain a higher temperature in the high-temperature air combustion chamber to ensure that the temperature is higher than the auto-ignition point of the fuel, achieve auto-ignition, and thus achieve high-temperature air combustion. The heat load generated by this process is relatively high and can meet the needs of high load.

[0079] It should be noted that due to sudden changes in the user's usage environment, such as pressure instability caused by high altitude areas or high floors or peak water usage, the water flow rate becomes intermittent during the combustion process, or the water temperature, such as the water temperature flowing through the pipe exposed to the sun, or the user resetting the target temperature, etc., frequently changes the heat load. If the heating mode is frequently switched directly according to the change of heat load, it is very easy to damage the gas water heater. For this reason, if Figure 8 As shown, in this embodiment, a reserved buffer room can be set to prevent the gas water heater from frequently changing the heating mode.

[0080] Specifically, when the required heat load is less than the first preset heat load and the first heating mode is selected for heating, if the required heat load gradually increases and is less than the maximum load Q1max of the preheating burner, the preheating burner is continuously controlled to operate until the required heat load is greater than the maximum load Q1max of the preheating burner.

[0081] When the required heat load is greater than or equal to the first preset heat load and the second heating mode is selected for heating, if the required heat load gradually decreases and is greater than the minimum load Q2min of the high-temperature air burner, the high-temperature air burner is continuously controlled to operate until the required heat load is less than the minimum load Q2min of the high-temperature air burner.

[0082] The buffer zone can be set between the minimum load Q2min of the high-temperature air burner and the maximum load Q1maxQ of the preheating burner. The minimum load Q2min of the high-temperature air burner is less than the maximum load Q1max of the preheating burner, that is, there is an intersection area between the preheating burner and the high-temperature air burner. In this buffer zone, if the current heating mode is the first heating mode, the first heating mode is maintained until the preheating burner cannot provide a higher heat load in the first heating mode, and then the preheating burner and the high-temperature air burner are switched to work at the same time. Similarly, if the current heating mode is the second heating mode, the first heating mode is maintained until the preheating burner can also provide a lower heat load in the second heating mode, and the high-temperature air burner does not need to work, and then it is switched to only the preheating burner working.

[0083] It is understandable that within the buffer area, the fluctuation area required for frequent changes in heat load caused by fluctuations caused by factors such as water inlet temperature, water inlet flow, or user resetting of target temperature can be satisfied. Of course, in other embodiments, the acquired heat load can also be timed. If the heat load after the change remains stable within a certain period of time, it means that the heat load demand is not suddenly changed due to the external environment, but is caused by the actual needs of the user. Of course, in other embodiments, if the required heat load jumps directly from the buffer zone to the heat load that can be provided by another heating mode, there is no need for buffering, and the jump can be made directly to respond to the needs of the user in a timely manner.

[0084] Reference Figure 3 and Figure 4 In one embodiment, after the step of calculating the heat load required for the gas water heater to heat the inlet water from the inlet water temperature to the target temperature according to the inlet water temperature, the inlet water flow rate and the target temperature, the gas water heater control method further includes the following steps:

[0085] Step S400: adjusting the opening of the gas valve of the gas water heater according to the heat load to adjust the flow output to the combustion chamber where the preheating burner and the high-temperature air burner are located.

[0086] Step S500, and / or, adjusting the speed of the fan of the gas water heater according to the heat load to adjust the air flow output to the combustion chamber where the preheating burner and the high-temperature air burner are located.

[0087] It is understandable that in the process of controlling the operation of the preheating burner and the high-temperature air burner, the inlet water must be heated from the inlet water temperature to the target temperature, and when the high-temperature air burner is burning, the set temperature of the high-temperature preheating air cannot be too low, and should not be lower than 600 degrees Celsius as much as possible. Generally, it is controlled at 600 to 1200 degrees Celsius to ensure that when the high-temperature gas contacts the gas in the high-temperature air combustion chamber, better automatic combustion is achieved, and ignition is no longer required. Among them, to achieve the target temperature and the set temperature required when the high-temperature air burner is working, it can be achieved by controlling the heating time, controlling the ratio of gas to air, keeping warm, and increasing the residence time of the high-temperature gas in the preheating combustion chamber. Specifically, it can be adjusted according to the target temperature, ambient temperature, inlet water flow, outlet water temperature, ambient pressure, etc., and the adjustment ratio and process can be pre-determined and set through experiments.

[0088] In this embodiment, the water inlet temperature t1 and the water inlet flow rate of the gas water heater are detected, and the water mass M is obtained according to the detected water inlet flow rate, and then the heat load Q required for the gas water heater to heat the water from the water inlet temperature to the target temperature is calculated based on the water inlet temperature t1, the obtained water mass M and the target temperature t2, and the corresponding heating mode is selected to control the operation of the preheating burner and the high-temperature air burner. In this heating mode, the valve opening of the gas valve can also be adjusted according to the heat load Q to adapt to the amount of gas required in this heating mode. Specifically, the target opening of the gas valve can be obtained according to the heat load Q required to heat the water from the water inlet temperature to the target temperature, and the gas valve can be adjusted to the target opening. In addition, when the outlet water temperature is consistent with the target temperature t2, the opening of the gas valve can be controlled to remain unchanged.

[0089] Similarly, in this heating mode, the speed of the fan can also be adjusted according to the heat load Q to adapt to the air volume required in this heating mode. Specifically, the target speed of the gas valve can be obtained according to the heat load Q required to heat the inlet water from the inlet water temperature to the target temperature, and the fan speed can be adjusted to the target speed. In addition, when the outlet water temperature is consistent with the target temperature t2, the fan speed can be controlled to remain unchanged.

[0090] It is also understandable that when the preheating combustion chamber and the high temperature air combustion chamber are provided with fuel gas and air, the preheating combustion chamber and / or the high temperature air combustion chamber may be provided with mixed mixer gas. Depending on whether the preheating combustion chamber and the high temperature air combustion chamber require the same ratio of mixed gas, the premixer may be configured as follows:

[0091] When the ratio of the mixed gas required by the two preheating combustion chambers and the high-temperature air combustion chamber is different, the number of premixers of the gas water heater can be two, one of which is used to premix the incoming air and the gas from the gas pipe, and provide the mixed gas to the preheating combustion chamber. Since the premixer provides a mixed gas containing gas and air, the mixed gas is output to the preheating combustion chamber, so that the preheating burner can ignite and burn the mixed gas, thereby achieving high-temperature preheating of air. The other premixer provides a mixed gas to the high-temperature air combustion chamber. Since the premixer provides a mixed gas containing gas and air, the mixed gas is output to the high-temperature air combustion chamber, and the burner pressurizes the mixed gas delivered to the high-temperature air combustion chamber to form a jet gas with a certain jet velocity to cooperate to produce a suction effect, so that the high-temperature flue gas refluxes, on the one hand, to achieve heat preservation so that the temperature is higher than the auto-ignition point of the fuel, so that the gas in the combustion chamber can self-ignite, and on the other hand, the air is diluted by jet suction so that the oxygen concentration is lower than a certain value, so as to achieve uniform combustion, so that high-temperature air combustion occurs in the combustion chamber, which can meet the MILD combustion requirements and reduce CO and NOx emissions.

[0092] When the mixed gas ratio requirements of the two preheating combustion chambers and the high-temperature air combustion chamber are the same, the total air and gas can be mixed, that is, a full premixer can be set. When full premixing is performed, in order to facilitate the mixing of gases, a mixed gas distribution chamber can be set or formed in the preheating burner, and the air inlet of the mixed gas distribution chamber is connected to the full premixer, and the air outlet of the mixed gas distribution chamber is connected to the preheating combustion chamber and the high-temperature air combustion chamber to distribute the mixed gas of the gas delivered to the preheating combustion chamber and the high-temperature air combustion chamber for ignition. The full premixer mixes the incoming air and gas and outputs them to the preheating combustion chamber and the high-temperature air combustion chamber respectively.

[0093] Reference Figure 5 In order to achieve energy conservation and emission reduction and maintain a constant outlet water temperature, in one embodiment, the gas water heater control method further includes the following steps:

[0094] Step S600, obtaining the outlet water temperature of the gas water heater;

[0095] Step S700: When the outlet water temperature reaches the target temperature, the heating modes of the preheating burner and the high-temperature air burner are updated according to the heat load, and the operation of the preheating burner and the high-temperature air burner is controlled.

[0096] In this embodiment, when the outlet water temperature is consistent with the target temperature, it means that the water heater has heated the inlet water from the inlet water temperature to the target temperature. At this time, the gas water heater can be controlled to enter the holding area, and the working mode of the gas water heater is controlled to be maintained in the first working mode, so that the outlet water temperature is consistent with the target temperature, so that the gas water heater has good constant temperature performance and good comfort, and energy saving and emission reduction can be achieved at the same time. Specifically, the current heating mode of the gas water heater can be determined according to the current heat load mode, and the heating mode can be updated to maintain the working mode of the gas water heater in the first working mode. For example, when the current working mode is determined to be the first working mode according to the heat load, the first working mode can be maintained. When the current working mode is determined to be the second working mode according to the heat load, the working mode can be updated to the first working mode to reduce energy consumption and reduce the power consumption of the gas water heater itself. This embodiment can further solve the problem of long preheating time required for small load state, reduce energy consumption, and improve the efficiency of the gas water heater. Therefore, when the heat load is small, the gas water heater can respond quickly, and when the heat load is large, the purpose of low CO&NOX emissions can be achieved. The present invention solves the problem that when the gas water heater is under low load, the preheating time is long and the energy consumption is high, so that the gas water heater cannot effectively respond to the needs of users. Or when the user needs a high preheating temperature, only ordinary combustion is used in a high load state, resulting in more pollutants such as NOx and CO.

[0097] The present invention also proposes a gas water heater control device, which includes a processor, a memory, and a gas water heater control program stored in the memory and executable on the processor, wherein the gas water heater control program implements the steps of the gas water heater control method described above when executed by the processor.

[0098] Reference Figure 6 , Figure 6 It is a schematic diagram of the terminal structure of the hardware operating environment of the gas water heater control device involved in the embodiment of the present invention.

[0099] The terminal of the embodiment of the present invention may be a PC, or a mobile terminal device with a display function such as a smart phone, a tablet computer, an e-book reader, an MP4 (Moving Picture Experts Group Audio Layer IV) player, or a portable computer. Figure 1The terminal may include a processor 1001 (e.g., a CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to realize the connection and communication between these components; the user interface 1003 may include a display screen (Display), an input unit such as a keyboard (Keyboard); the network interface 1004 may optionally include a standard wired interface, a wireless interface (such as a WI-FI interface); the memory 1005 may be a high-speed RAM memory, or a stable memory (non-volatile memory), such as a disk memory, and the memory 1005 may optionally be a storage device independent of the aforementioned processor 1001.

[0100] Those skilled in the art will understand that Figure 7 The terminal structure of the device hardware operating environment shown in the figure does not constitute a limitation on the gas water heater control device of the present invention, and may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0101] Reference Figure 7 Furthermore, in the above embodiment, the gas water heater control device also includes an inlet water temperature sensor T11 arranged on the side of the water inlet pipe, an outlet water temperature sensor T12 arranged on the side of the water outlet pipe, and a water flow sensor A3 arranged in the water inlet pipe. The inlet water temperature is detected by the inlet water temperature sensor T11, and the inlet water flow rate is detected by the water flow sensor A3. The water mass M is obtained according to the detected inlet water temperature and inlet water flow rate, and according to the detected inlet water flow rate, and then the heat load Q required for the gas water heater to heat the inlet water from the inlet water temperature to the target temperature is calculated by the inlet water temperature T1, the obtained water mass M and the target temperature T2. The present invention solves the problem that the gas water heater adopts high-temperature air combustion at low load, resulting in a long preheating time and high energy consumption, so that the gas water heater cannot effectively respond to the needs of users. Or when the temperature required for preheating by the user is high, only ordinary combustion is used in a large load state, resulting in more pollutants such as NOx and CO.

[0102] The present invention further provides a computer-readable storage medium, on which a gas water heater control program is stored. When the gas water heater control program is executed by a processor, the steps of the gas water heater control method described above are implemented.

[0103] The present invention further proposes a computer-readable storage medium, on which a gas water heater control program is stored. When the gas water heater control program is executed by a processor, the steps of the gas water heater control method described above are implemented.

[0104] Reference Figure 7The present invention further proposes a gas water heater, which is provided with a cold water inlet pipe 200 and a hot water outlet pipe 300, and the gas water heater comprises:

[0105] The housing 100 forms a combustion chamber therein;

[0106] A high temperature air burner 10 is installed in the combustion chamber;

[0107] A preheating burner 20 is installed in the combustion chamber and arranged adjacent to the high temperature air burner 10;

[0108] A heat exchanger 30, one end of which is connected to the cold water inlet pipe 200, and the other end of which is connected to the hot water outlet pipe 300, and the heat exchanger 30 is used to absorb the heat generated by the combustion of the preheating burner 20 and the combustion of the high-temperature air burner 10 and to exchange the absorbed heat with the water inside the heat exchanger 30; and,

[0109] As described above, the gas water heater control device is used to select the heating mode of the preheating burner 20 and the high-temperature air burner 10 according to the acquired heat load, so as to heat the inlet water from the inlet water temperature to the target temperature.

[0110] The detailed structure of the gas water heater control device can be referred to the above-mentioned embodiment, which will not be repeated here; it can be understood that since the above-mentioned gas water heater control device is used in the gas water heater of the present invention, the embodiment of the gas water heater of the present invention includes all technical solutions of all embodiments of the above-mentioned gas water heater control device, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0111] In this embodiment, the gas water heater control device is used to detect the inlet water temperature and the inlet water flow of the gas water heater, so as to calculate the gas water heater to heat the inlet water from the inlet water temperature to the target temperature according to the inlet water temperature, the inlet water flow and the target temperature; and select the first heating mode or the second heating mode to perform heating work according to the heat load, so that the heat exchanger 30 absorbs the heat generated by the combustion of the preheating burner 20 and the combustion of the high-temperature air burner 10 and exchanges the absorbed heat with the water inside the heat exchanger 30, so as to heat the inlet water from the inlet water temperature to the target temperature. In the first heating mode, the preheating burner 20 is controlled to work, and in the second heating mode, the preheating burner 20 and the high-temperature air burner 10 are controlled to work.

[0112] In the above embodiment, the gas water heater further includes a fan 40 that can control air entry, a gas valve 50 that controls gas entry, and a gas injection pipe (not shown), which has a gas inlet and a gas outlet. The gas outlet of the gas injection pipe is arranged in the high-temperature air combustion chamber to inject gas into the high-temperature air combustion chamber, so that a high-temperature air combustion reaction is carried out in the high-temperature air combustion chamber. After the high-temperature gas after high-temperature preheating is sent into the high-temperature air combustion chamber, the gas injection pipe is controlled to inject gas, the gas is combined with the high-temperature gas, and the high-temperature gas ignites the gas to realize MILD combustion in the high-temperature air combustion chamber. Since the gas is injected through the gas injection pipe, a suction effect will be formed in the high-temperature air combustion chamber, so that a jet combustion zone and a flue gas recirculation zone are formed in the high-temperature air combustion chamber, so that part of the high-temperature flue gas (waste gas rich in N2 and CO2) is strongly circulated internally in the high-temperature air combustion chamber to dilute the reactants, and then the injected gas and air are fully diluted to form a lower oxygen concentration, reduce the combustion reaction speed, and maintain a higher temperature in the high-temperature air combustion chamber to ensure that the temperature is higher than the auto-ignition point of the fuel, and achieve auto-ignition, thereby realizing high-temperature air combustion. There are two gas valves 50, one for controlling the gas flow entering the preheating combustion chamber, and the other for controlling the gas flow entering the high-temperature air combustion chamber. By controlling the rotation speed of the fan 40 and the opening of the two gas valves 50, the mixing ratio of gas and air can be achieved. In some further embodiments, a booster device can be provided between the fan 40 and the combustion chamber, and / or a booster device can be provided between the gas valve 50 and the combustion chamber to increase the jet velocity of air and / or gas when entering the high-temperature air combustion chamber, thereby meeting the MILD combustion requirements.

[0113] The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A gas water heater control method, characterized in that: The gas water heater comprises a preheating burner and a high-temperature air burner which receives the high-temperature flue gas generated by the preheating burner to generate high-temperature air combustion. The gas water heater control method comprises the following steps: Detecting the water inlet temperature and water inlet flow rate of the gas water heater; Calculating the heat load required for the gas water heater to heat the inlet water from the inlet water temperature to the target temperature according to the inlet water temperature, the inlet water flow rate and the target temperature; and The calculated heat load is matched with the heat load interval range under the first heating mode and the second heating mode respectively to heat the inlet water from the inlet water temperature to the target temperature. When the calculated heat load is in the heat load interval range corresponding to the first heating mode, the preheating burner is controlled to operate; when the calculated heat load is in the heat load interval range corresponding to the second heating mode, the preheating burner and the high-temperature air burner are controlled to operate simultaneously; wherein, in the first heating mode and the second heating mode, the gas water heater can provide a heat load in the corresponding interval range.

2. The gas water heater control method according to claim 1, characterized in that: When the calculated heat load is within the heat load interval corresponding to the first heating mode, the preheating burner is controlled to work; when the calculated heat load is within the heat load interval corresponding to the second heating mode, the preheating burner and the high-temperature air burner are controlled to work simultaneously. The steps specifically include: When the calculated heat load is within the heat load interval corresponding to the first heating mode, controlling the preheating burner to perform heating according to the first heating mode; When the calculated heat load is within the heat load interval corresponding to the second heating mode, the preheating burner and the high-temperature air burner are controlled to perform heating work according to the second heating mode at the same time.

3. The gas water heater control method according to claim 2, characterized in that: In the first heating mode and the second heating mode, the gas water heater can provide a heat load in a corresponding range, and the heat load in the corresponding range provided includes a first preset heat load, which is greater than or equal to the minimum output heat load of the high-temperature air burner and less than the maximum output heat load of the preheating burner; Alternatively, the first preset heat load is greater than the minimum output heat load of the high temperature air burner and less than or equal to the maximum output heat load of the preheating burner.

4. The gas water heater control method according to claim 2, characterized in that: In the first heating mode and the second heating mode, the gas water heater can provide a heat load in a corresponding range, and the heat load in the corresponding range provided includes a first preset heat load. When the required heat load is less than the first preset heat load and the first heating mode is selected for heating, if the required heat load gradually increases and is less than the maximum load Q1max of the preheating burner, the preheating burner is continuously controlled to operate until the required heat load is greater than the maximum load Q1max of the preheating burner.

5. The gas water heater control method according to claim 2, characterized in that: In the first heating mode and the second heating mode, the gas water heater can provide a heat load in a corresponding range, and the heat load in the corresponding range provided includes a first preset heat load. When the required heat load is greater than or equal to the first preset heat load and the second heating mode is selected for heating, if the required heat load gradually decreases and is greater than the minimum load Q2min of the high-temperature air burner, the high-temperature air burner is continuously controlled to operate until the required heat load is less than the minimum load Q2min of the high-temperature air burner.

6. The gas water heater control method according to claim 1, characterized in that: In the second heating mode, the steps of controlling the operation of the preheating burner and the high temperature air burner specifically include: Controlling the preheating burner to start up to burn the formed high-temperature flue gas; and, The high-temperature air burner is controlled to operate, and is connected to the preheating burner to cause high-temperature air combustion.

7. The gas water heater control method according to claim 1, characterized in that: After the step of calculating the heat load required for the gas water heater to heat the inlet water from the inlet water temperature to the target temperature according to the inlet water temperature, the inlet water flow rate and the target temperature, the gas water heater control method further includes the following steps: The opening of the gas valve of the gas water heater is adjusted according to the heat load to adjust the gas flow output to the combustion chamber where the preheating burner and the high-temperature air burner are located.

8. The gas water heater control method according to claim 1, characterized in that: After the step of calculating, according to the inlet water temperature, the inlet water flow rate and the target temperature, that the gas water heater heats the inlet water from the inlet water temperature to the target temperature, the gas water heater control method further comprises the following steps: The speed of the fan of the gas water heater is adjusted according to the heat load to adjust the air flow output to the combustion chamber where the preheating burner and the high-temperature air burner are located.

9. The gas water heater control method according to claim 1, characterized in that: The gas water heater control method further comprises the following steps: Obtaining the outlet water temperature of the gas water heater; and, When the outlet water temperature reaches the target temperature, the heating modes of the preheating burner and the high-temperature air burner are updated according to the heat load, and the operations of the preheating burner and the high-temperature air burner are controlled.

10. The gas water heater control method according to any one of claims 1 to 9, characterized in that: The heat load is calculated according to the following formula: Q=C*M*(T2-T1) Among them, Q is the heat load; C is the specific heat capacity of water; M is the mass of water and is obtained according to the water inlet flow rate; T2 is the target temperature; and T1 is the water inlet temperature.

11. A gas water heater control device, characterized in that: The gas water heater control device includes a processor, a memory, and a gas water heater control program stored in the memory and executable on the processor; wherein, when the gas water heater control program is executed by the processor, the steps of the gas water heater control method as described in any one of claims 1 to 10 are implemented.

12. A gas water heater, provided with a cold water inlet pipe and a hot water outlet pipe, characterized in that: The gas water heater comprises: a casing, the interior of which forms a combustion chamber; A high temperature air burner installed in the combustion chamber; A preheating burner installed in the combustion chamber and arranged adjacent to the high-temperature air burner; a heat exchanger, one end of which is connected to the cold water inlet pipe and the other end of which is connected to the hot water outlet pipe, the heat exchanger being used to absorb the heat generated by the combustion of the preheating burner and the combustion of the high-temperature air burner and to exchange the absorbed heat with the water inside the heat exchanger; and, The gas water heater control device as described in claim 11 is used to adjust the heating mode of the preheating burner and the high-temperature air burner according to the acquired heat load to heat the inlet water from the inlet water temperature to the target temperature.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a gas water heater control program, and when the gas water heater control program is executed by the processor, the steps of the gas water heater control method according to any one of claims 1 to 10 are implemented.

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