Gas water heating equipment and control method and control device thereof

Abstract

The invention discloses gas water heating equipment and a control method and a control device thereof, and the control method comprises the following steps: when an instruction of transferring fire to a target combustion unit is received, the current fan rotating speed and the current secondary pressure of a gas proportional valve are obtained; the current fan rotating speed is adjusted to the fire transfer fan rotating speed FC, and the current gas proportional valve secondary pressure is adjusted to the fire transfer secondary pressure CH; in the process of adjusting the secondary pressure of the gas proportional valve, the mapping relation P = f (r) between the secondary pressure of the gas proportional valve and the rotating speed of a fan is controlled to be kept, so that the air-fuel ratio of the gas water heating equipment is constantly within a preset interval, ensuring that the secondary pressure of the gas proportional valve at any moment in the adjusting process is greater than a secondary pressure flameout threshold value CH'min corresponding to the rotating speed of the fan at the same moment; and the target section valve corresponding to the target combustion unit is controlled to be opened. According to the technical scheme, the problem of poor fire transfer during segmented combustion can be solved, the fire transfer reliability is improved, and then the quality reliability of the gas water heating equipment is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas water heaters, and in particular to a gas water heater and a control method and a control device thereof. Background Art

[0002] At present, most of the burners of gas water heaters (such as gas water heaters or wall-mounted boilers) are segmented burners. The segmented burner includes multiple combustion units, each of which includes a number of burner monoliths assembled side by side. The segmented combustion is achieved by controlling the opening and closing of the segmented valves corresponding to each combustion unit, so as to meet the large-volume hot water demand of multiple water points in winter and the small-volume hot water demand of a single tap in summer.

[0003] However, in the process of segmented flame transmission of traditional gas water heaters, the secondary gas pressure and fan speed often change suddenly, and the speed of change of the two is inconsistent, which easily leads to the phenomenon of air-fuel ratio mismatch. When the fan speed is too high, it is easy to blow out the flame, and then the gas water heater will restart, and the user will experience hot and cold phenomena when using it. Generally, after multiple flame transmission and flameout, the gas water heater will report an unexpected flameout failure, and the user needs to restart the gas water heater before continuing to use it. Even after restarting, it still frequently reports an unexpected flameout failure, and it cannot be used normally, which seriously affects the user experience. Therefore, flame transmission and flameout, and hot and cold water temperature are currently an important customer complaint quality issue of gas water heaters. Summary of the invention

[0004] The main purpose of the present invention is to propose a control method for a gas water heater, aiming to solve the problem of poor fire transmission during segmented combustion, improve the reliability of fire transmission, and further improve the quality reliability of the gas water heater.

[0005] To achieve the above object, the control method of the gas water heater proposed in the present invention comprises the following steps:

[0006] When receiving the instruction to transmit fire to the target combustion unit, the current fan speed and the current secondary pressure of the gas proportional valve are obtained;

[0007] Adjust the current fan speed to the flame transfer fan speed FC and adjust the current gas proportional valve secondary pressure to the flame transfer secondary pressure CH; during the adjustment of the gas proportional valve secondary pressure, control the mapping relationship between the gas proportional valve secondary pressure and the fan speed P = f (r) to keep the air-fuel ratio of the gas water heater constant in the preset range, and ensure that the gas proportional valve secondary pressure at any time during the adjustment process is greater than the secondary pressure flameout threshold CH' corresponding to the fan speed at the same time min ;

[0008] The target segmented valve corresponding to the target combustion unit is controlled to open so that the target combustion unit can burn.

[0009] In one embodiment, the steps of adjusting the current fan speed to the flame transfer fan speed FC and adjusting the current gas proportional valve secondary pressure to the flame transfer secondary pressure CH include:

[0010] Under the condition that the time required for the secondary pressure of the gas proportional valve to decrease from the maximum secondary pressure PH to the minimum secondary pressure PL is the same as the time required for the fan speed to decrease from the maximum fan speed FH to the minimum fan speed FL, determine the speed change rate of the fan and the pressure change rate of the secondary pressure of the gas proportional valve;

[0011] The secondary pressure of the gas proportional valve is controlled according to the speed change rate and the pressure change rate to start adjusting at the same time as the fan speed, until the fan speed is adjusted to the flame transfer fan speed FC, and the secondary pressure of the gas proportional valve is adjusted to the flame transfer secondary pressure CH.

[0012] In one embodiment, the fire transmission secondary pressure CH is set to be greater than the secondary pressure CH' corresponding to the fire transmission fan speed FC according to the mapping relationship P=f(r).

[0013] In one embodiment, before the step of controlling the target segmented valve corresponding to the target combustion unit to open, the method further includes:

[0014] Get the moment when the fan speed starts to be adjusted;

[0015] The time for opening the target sectional valve is determined according to the time when the fan speed starts to be adjusted and the preset time, so that the time when the target sectional valve is opened is delayed by the preset time compared with the time when the fan speed starts to be adjusted, and the time when the target sectional valve completes opening is no earlier than the time when the fan speed drops to the fire transmission fan speed FC.

[0016] In one embodiment, the step of controlling the opening of the target segmented valve corresponding to the target combustion unit is specifically:

[0017] The target sectional valve is controlled to open when the fan speed drops to the fire transfer fan speed FC; or, the target sectional valve is controlled to open after the fan speed drops to the fire transfer fan speed FC.

[0018] In one embodiment, the flameout secondary pressure threshold CH' corresponding to the flameout fan speed FC min Less than the minimum secondary pressure of the fire transmission CH min , where the minimum secondary pressure of the fire transmission is CH min It is the minimum value of the secondary pressure drop when the target sectional valve is opened.

[0019] In one embodiment, the average value of the maximum secondary pressure PH and the minimum secondary pressure PL of the gas proportional valve is taken as the reference secondary pressure P, and the value of the flame transmission secondary pressure CH is within the range of [P±10%].

[0020] In one embodiment, before the step of receiving the instruction to transmit fire to the target combustion unit, the method further includes:

[0021] Determine whether the combustion of the current combustion unit meets the hot water demand under the current working conditions;

[0022] If the hot water demand is not met, the fan speed under the current working condition is adjusted to the maximum fan speed FH, and the secondary pressure of the gas proportional valve is adjusted to the maximum secondary pressure PH;

[0023] Determine whether the current combustion unit meets the hot water demand under the adjusted working conditions;

[0024] If the hot water demand is not met, a command is issued to transfer fire to the target combustion unit.

[0025] The present invention also provides a control device for a gas water heater, comprising:

[0026] A memory, wherein the memory stores a control program of the gas water heater;

[0027] A processor, wherein the processor is used to execute the control program of the gas water heater to implement the control method of the gas water heater as described above.

[0028] The present invention also provides a gas water heater, wherein the gas water heater uses the control method of the gas water heater as described above;

[0029] Or include the control device of the gas water heater as described above.

[0030] The technical solution of the present invention controls the mapping relationship between the secondary pressure of the gas proportional valve and the fan speed to maintain P = f (r) during the adjustment process of the secondary pressure of the gas proportional valve, so that the air-fuel ratio of the gas water heater is constant in a preset range, ensuring that the secondary pressure of the gas proportional valve at any time during the adjustment process is greater than the secondary pressure flameout threshold CH' corresponding to the fan speed at the same time min , thereby preventing the fan speed from being too high and blowing out the flame, and avoiding the risk of flame transmission and flameout, thereby solving the problem of poor flame transmission during segmented combustion, improving the reliability of flame transmission, and thus improving the quality reliability of the gas water heater. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] 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.

[0032] Figure 1 It is a structural schematic diagram of an embodiment of a gas water heater of the present invention;

[0033] Figure 2 for Figure 1 Schematic diagram of the matching structure of the middle burner and the gas distribution rod;

[0034] Figure 3 for Figure 2 A schematic diagram of the matching structure of the middle burner and the gas distribution rod from another perspective;

[0035] Figure 4 This is a schematic diagram of fan speed, secondary pressure and sectional valve opening when the existing control method is used to transmit fire;

[0036] Figure 5 This is a schematic diagram of the fan speed, secondary pressure and sectional valve opening when the existing control method is used for fire transmission (the secondary pressure fluctuates and decreases at the moment of valve opening);

[0037] Figure 6 A schematic diagram of fan speed, secondary pressure and sectional valve opening when the control method of one embodiment of the present invention is used for fire transmission;

[0038] Figure 7 A schematic diagram of fan speed, secondary pressure and sectional valve opening when the control method of another embodiment of the present invention is used for fire transmission;

[0039] Figure 8 A schematic diagram of fan speed, secondary pressure and sectional valve opening when the control method according to another embodiment of the present invention is used for fire transmission;

[0040] Fig. 9 It is a flow chart of a control method of a gas water heater according to a first embodiment of the present invention;

[0041] Fig.10 It is a flow chart of a control method of a gas water heater according to a second embodiment of the present invention;

[0042] Fig.11 It is a flowchart of a control method of a gas water heater according to a third embodiment of the present invention;

[0043] Fig.12 Schematic diagram of a flow chart of a control method for a gas water heater according to a fourth embodiment of the present invention.

[0044] Description of Figure Numbers:

[0045] Label name Label name 100 Gas water heater 61 First section valve 10 case 62 Second section valve 20 Hood 63 The third section valve 30 Heat Exchanger 70 Fan 40 Burner 80 Water Proportional Valve 41 The first combustion unit 90 Controller 42 Second combustion unit 11 Air intake connector 43 The third combustion unit 12 Cold water inlet connector 50 Gas Proportional Valve 13 Hot water outlet connector 60 Gas rod 14 Power cord

[0046] 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

[0047] 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.

[0048] 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 in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0049] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0050] See also Figure 1 , is a schematic diagram of the structure of a gas water heater 100 according to an embodiment of the present invention. The gas water heater 100 includes but is not limited to a gas water heater or a wall-mounted boiler.

[0051] The gas water heater 100 comprises a housing 10, and components such as a smoke hood 20, a heat exchanger 30, a burner 40, a gas proportional valve 50, a gas distribution rod 60, a fan 70, a water proportional valve 80 and a controller 90 arranged in the housing 10. The smoke hood 20 is arranged on the top of the heat exchanger 30, the heat exchanger 30 is arranged on the top of the burner 40, and the fan 70 and the gas distribution rod 60 are both arranged on the bottom of the burner 40. The housing 10 is also provided with an air inlet joint 11, a cold water inlet joint 12, a hot water outlet joint 13 and a power line 14. Among them, the air inlet connector 11 is connected to the burner 40 via the gas proportional valve 50 and the gas distribution rod 60. The gas proportional valve 50 can be used to adjust the amount of gas delivered to the burner 40, and the gas distribution rod 60 can be used to distribute gas to the burner 40; the fan 70 is used to deliver air to the burner 40, and the amount of air delivered to the burner 40 can be adjusted by adjusting the rotation speed of the fan 70; the cold water inlet connector 12 is connected to the water inlet pipe of the heat exchanger 30, the water proportional valve 80 is arranged on the water inlet pipe, and the water outlet pipe of the heat exchanger 30 is connected to the hot water outlet connector 13. When the gas water heater 100 is working, air and gas are mixed in a certain ratio in the burner 40 to form an air-fuel mixture. After the burner 40 is ignited, the air-fuel mixture burns in the combustion chamber of the burner 40 to generate high-temperature flue gas. The high-temperature flue gas exchanges heat with the heat exchanger 30, thereby heating the cold water transported to the heat exchanger 30 from the cold water inlet connector 12 to form hot water. The hot water in the heat exchanger 30 is output through the hot water outlet connector 13 to meet the user's hot water needs. The specific working principles of the gas water heater and the wall-mounted boiler are well known to those skilled in the art and will not be described in detail here.

[0052] The burner 40 of the gas water heater 100 specifically relates to a segmented burner 40 capable of segmented combustion. Specifically, the burner 40 includes at least two segments of combustion units, each group of combustion units includes a number of burner monoliths arranged side by side, and a gas distribution channel is provided in the gas distribution rod 60 corresponding to each group of combustion units, and the air inlet end of each gas distribution channel is provided with a segmented valve (specifically, a solenoid valve) for controlling the on-off of the air inlet, and the air outlet end of each gas distribution channel is provided with a nozzle that is the same as the number of gas monoliths of the corresponding combustion unit and corresponds to each other. The gas is ejected from the nozzle of the gas distribution rod 60, and the surrounding air (i.e., primary air) is drawn into the flow channel of the burner 40, and after mixing, it is ejected from the fire hole at the top of the burner 40. The tip of the ignition needle is placed above the fire hole of a burner monolith, ignites the air-fuel mixture ejected from the fire hole, forms a flame, and then transmits it to the other burner monoliths on both sides. The following mainly takes a burner 40 capable of four-segmented combustion as an example for explanation.

[0053] like Figure 2 and Figure 3As shown, in one embodiment, the burner 40 of the gas water heater 100 includes 18 burner monoliths arranged side by side, and the 18 burner monoliths can be divided into 1-11 burner monoliths, 12-15 burner monoliths, and 16-18 burner monoliths from left to right. Among them, 12-15 burner monoliths constitute the first combustion unit 41, 16-18 burner monoliths constitute the second combustion unit 42, and 1-11 burner monoliths constitute the third combustion unit 43. Correspondingly, a first gas distribution channel corresponding to the first combustion unit 41, a second gas distribution channel corresponding to the second combustion unit 42, and a third gas distribution channel corresponding to the third combustion unit 43 are provided in the gas distribution rod 60. A first segment valve 61 is provided at the air inlet end of the first gas distribution channel; a second segment valve 62 is provided at the air inlet end of the second gas distribution channel; and a third segment valve 63 is provided at the air inlet end of the third gas distribution channel. The outlet end of the first gas distribution channel corresponds to the 12-15 burner monolith with a 12-15 nozzle; the outlet end of the second gas distribution channel corresponds to the 16-18 burner monolith with a 16-18 nozzle; the outlet end of the third gas distribution channel corresponds to the 1-11 burner monolith with a 1-11 nozzle. An ignition needle is correspondingly arranged above the first combustion unit 41 (i.e., the 12-15 burner monolith).

[0054] When igniting, first open the first segment valve 61, ignite the air-fuel mixture of the 12-15 burner monolithic, and realize that 12-15 burners, a total of 4 monolithic burners, burn. When it is necessary to further increase the combustion firepower, open the second segment valve 62, and the flame of the first combustion unit 41 is transferred to the second combustion unit 42 (i.e., 16-18 burner monolithic), and realize that 12-18 burners, a total of 7 monolithic burners, burn. When it is necessary to further increase the combustion firepower, open the third segment valve 63, and the flame of the first combustion unit 41 is transferred to the third combustion unit 43 (i.e., 1-11 burner monolithic), and then the first combustion unit 41 and the second combustion unit 42 are extinguished, and realize that 1-11 burners, a total of 11 monolithic burners, burn. When the first segment valve 61, the second segment valve 62 and the third segment valve 63 are all opened, it can be realized that 18 monolithic burners, a total of 18 monolithic burners, burn. In this way, the burner 40 described above can realize 4-7-11-18 four-stage combustion.

[0055] The flame transfer process of the burner 40 is analyzed below.

[0056] The controller 90 sets the maximum secondary pressure PH and the maximum fan speed FH of the gas proportional valve, and the air-fuel ratio of the two is matched; the secondary pressure CH and the fan speed FC of the fire transmission are set, and the air-fuel ratio of the two is matched. After ignition, the first segmented valve 61 is opened to ignite the air-fuel mixture of the 12-15 burner monolith, and the first combustion unit 41 is used for combustion at this time. When the secondary pressure is PH and the fan speed is FH, the combustion of the first combustion unit 41 cannot meet the user's hot water demand, then the second segmented valve 62 is opened, and the flame is transferred to the 16-18 burner monolith, and the first combustion unit 41 and the second combustion unit 42 are used for combustion together. When the secondary pressure is PH and the fan speed is FH, the first combustion unit 41 and the second combustion unit 42 still cannot meet the user's hot water demand by burning together, then the third segmented valve 63 is opened, the flame is transferred to the 1-11 burner monolith, and then the flame of the 12-18 burner monolith is extinguished, and the third combustion unit 43 is used for combustion. At this time, since the flames of the seven burner pieces 12-18 will be extinguished, the risk of flameout in this fire transmission is the highest.

[0057] When the first combustion unit 41 and the second combustion unit 42 (i.e., seven burner chips 12-18) are combined to burn and still cannot meet the user's hot water demand, it is necessary to transfer fire to the third combustion unit 43 (i.e., 11 burner chips 1-11) and use the third combustion unit 43 for combustion. Figure 4 As shown, the existing control program is to simultaneously (for example, at time t1) reduce the fan speed from the highest fan speed FH to the flame transfer fan speed FC, reduce the secondary pressure of the gas proportional valve from the maximum secondary pressure PH to the flame transfer secondary pressure CH, and open the third segment valve 63 at the same time. However, due to inertia, the fan speed, the secondary pressure of the gas proportional valve, and the segment valve cannot achieve sudden changes, but take a period of time to change to the target value. Among them, the time for the fan speed to drop is ΔT1, and the time for the gas proportional valve secondary pressure to drop is ΔT2, ΔT1 = t2-t1,, ΔT2 = t3-t1, due to the inherent properties of the fan 70 and the gas proportional valve 50, ΔT2 < < ΔT1, the gas secondary pressure quickly drops from the maximum secondary pressure PH to the flame transfer secondary pressure CH, but the fan speed is still in the process of decreasing. At this time, the air-fuel ratio does not match, the fan speed is much higher than the required speed value, and higher than the flameout threshold, so the flame is extinguished.

[0058] And, if Figure 5As shown, the existing control program will open the third segmented valve 63 at time t1, and the opening time of the third segmented valve 63 (ΔT3=t4-t1) is shorter than the time when the secondary pressure drops, that is, ΔT3<ΔT2<<ΔT1. When the third segmented valve 63 is opened, the first segmented valve 61 and the second segmented valve 62 will remain open for a short time. During this time period, the three segmented valves remain open at the same time, and the secondary pressure will drop for a short time. This drop in secondary pressure makes the air-fuel ratio more mismatched, the fan speed is higher than the required speed value, and is higher than the flameout threshold, so the flame is easier to extinguish.

[0059] Based on the problem of poor fire transmission in traditional gas water heaters 100, the present invention proposes a control method for the gas water heater 100, which can solve the problem of poor fire transmission during segmented combustion, improve the reliability of fire transmission, and further improve the quality reliability of the gas water heater 100.

[0060] Please refer to Figures 1 to 3 In one embodiment of the present invention, the gas water heater 100 includes a burner 40, a gas proportional valve 50 and a fan 70. The gas proportional valve 50 is used to control the amount of gas entering the burner 40. The fan 70 is used to control the amount of air entering the burner 40. The burner 40 includes at least two combustion units, and the air inlet end of each of the combustion units is respectively provided with a sectional valve for controlling the on-off of the air inlet.

[0061] It should be noted that the gas water heater 100 includes but is not limited to a gas water heater or a wall-mounted boiler; the gas water heater may be a strong drum type gas water heater with a fan 70 placed below, or a strong extraction type gas water heater with a fan 70 placed above. The burner 40 of the gas water heater 100 is a segmented burner, which may be two-segment, three-segment, four-segment, etc. Figures 1 to 3 The control method of a strong drum type gas water heater is used as an example for illustration. Of course, the control method of the gas water heater 100 can also be applied to other types of gas water heaters and wall-mounted boilers, all of which are within the scope of protection of the present invention. Figures 1 to 3 The specific structure of the strong drum type gas water heater shown has been described in detail above and will not be repeated here.

[0062] Please refer to Fig. 9 In one embodiment of the present invention, the control method of the gas water heater 100 comprises the following steps:

[0063] S1. When receiving the instruction to transmit fire to the target combustion unit, obtain the current fan speed and the current secondary pressure of the gas proportional valve;

[0064] Specifically, when the gas water heater receives an instruction to transfer fire to the target combustion unit, the current fan speed and the current secondary pressure of the gas proportional valve are obtained. It is understandable that when the current combustion unit is in the maximum firepower condition (that is, the condition of the highest fan speed and the maximum secondary pressure of the gas proportional valve) and the combustion still does not meet the user's hot water demand, it is necessary to transfer fire to the target combustion unit. That is, when executing the fire transfer instruction, the current fan speed is generally the highest fan speed or close to the highest fan speed, and the current gas proportional valve secondary pressure is generally the maximum secondary pressure of the gas proportional valve or close to the maximum secondary pressure of the gas proportional valve. Of course, in some cases, when the current combustion unit has not yet received the fire transfer instruction under the maximum firepower condition, the fire transfer step can also be executed.

[0065] S2, adjust the current fan speed to the flame transfer fan speed FC and adjust the current gas proportional valve secondary pressure to the flame transfer secondary pressure CH; during the adjustment of the gas proportional valve secondary pressure, control the mapping relationship between the gas proportional valve secondary pressure and the fan speed P = f (r) to keep the air-fuel ratio of the gas water heater constant in the preset range, and ensure that the gas proportional valve secondary pressure at any time during the adjustment process is greater than the secondary pressure flameout threshold CH' corresponding to the fan speed at the same time min ;

[0066] Specifically, take the current fan speed as the maximum fan speed FH, and the current gas proportional valve secondary pressure as the maximum secondary pressure PH as an example; adjust the fan speed from the maximum fan speed FH to the flame transmission fan speed FC, and adjust the gas proportional valve secondary pressure from the maximum secondary pressure PH to the flame transmission secondary pressure CH. Among them, the flame transmission fan speed FC and the flame transmission secondary pressure CH are preset values ​​pre-stored in the control program. During the adjustment process of the gas proportional valve secondary pressure (for example, during the entire decrease process of the gas proportional valve secondary pressure), the mapping relationship between the gas proportional valve secondary pressure and the fan speed is controlled to be maintained P=f(r). Among them, P represents the gas proportional valve secondary pressure, and f(r) is a functional relationship with the fan speed as a variable, so that the gas proportional valve secondary pressure can change with the change of the fan speed. Since the size of the gas proportional valve secondary pressure is related to the amount of gas delivered to the burner, and the size of the fan speed is related to the amount of air delivered to the burner, the air-fuel ratio of the gas water heater is constant in the preset interval during the adjustment process of the gas proportional valve secondary pressure. The preset interval can be an interval that fluctuates above and below the optimal air-fuel ratio to achieve the optimal combustion state. That is, during the adjustment of the secondary pressure of the gas proportional valve, the air-fuel ratio of the gas water heater is always matched. In this way, it can be ensured that the secondary pressure of the gas proportional valve at any time during the adjustment process is greater than the secondary pressure flameout threshold CH' corresponding to the fan speed at the same time. min , thus preventing the fan from spinning too fast and blowing out the flame.

[0067] S3. Control the target segmented valve corresponding to the target combustion unit to open, so that the target combustion unit burns.

[0068] Specifically, at the moment when the fan speed begins to be adjusted or thereafter, the target segmented valve is controlled to open. After the target segmented valve is opened, the gas distribution channel corresponding to the target combustion unit is opened, and gas can be delivered to the target combustion unit. The flame transmitted by the current combustion unit ignites the air-fuel mixture of the target combustion unit to make the target combustion unit burn; the fire transfer process is thus completed. After the fire transfer is completed, the current combustion unit can continue to burn, or the segmented valve corresponding to the current combustion unit can be closed, and the current combustion unit is extinguished. For example, Figure 3 As shown, the burner 40 includes a first combustion unit 41, a second combustion unit 42 and a third combustion unit 43. When the first combustion unit 41 and the second combustion unit 42 (i.e., seven burner monoliths 12-18 in total) are jointly burned under the conditions of the highest fan speed FH and the maximum secondary pressure PH and still cannot meet the user's large hot water demand, it is necessary to transfer fire to the third combustion unit 43 (i.e., 11 burner monoliths 1-11 in total). At this time, the first combustion unit 41 and the second combustion unit 42 can be regarded as the current combustion unit, the third combustion unit 43 can be regarded as the target combustion unit, and the third segment valve 63 corresponding to the third combustion unit 43 is the target segment valve.

[0069] In the prior art, the fan speed and the secondary pressure of the gas proportional valve are adjusted independently, and there is no correlation between the two. Due to the inherent properties of the fan 70 and the gas proportional valve 50, the time required for the secondary pressure of the gas proportional valve to decrease from the maximum secondary pressure PH to the secondary pressure CH is much shorter than the time required for the fan speed to decrease from the maximum fan speed FH to the fan speed CH. When the secondary pressure of the gas proportional valve is rapidly reduced to the secondary pressure CH, the fan speed is still in the process of decreasing. At this time, the air-fuel ratio does not match, the fan speed is much higher than the required speed value, and higher than the flameout threshold, so the flame is extinguished.

[0070] The technical solution of the present invention controls the mapping relationship between the secondary pressure of the gas proportional valve and the fan speed to maintain P = f (r) during the adjustment process of the secondary pressure of the gas proportional valve, so that the air-fuel ratio of the gas water heater is constant in a preset range, ensuring that the secondary pressure of the gas proportional valve at any time during the adjustment process is greater than the secondary pressure flameout threshold CH' corresponding to the fan speed at the same time min , thereby preventing the fan from blowing out the flame due to excessive speed, and avoiding the risk of flame transmission and flameout, thereby solving the problem of poor flame transmission during staged combustion, improving the reliability of flame transmission, and further improving the quality reliability of the gas water heater 100.

[0071] Please refer to Fig.10In one embodiment, the steps of adjusting the current fan speed to the flame transfer fan speed FC and adjusting the current gas proportional valve secondary pressure to the flame transfer secondary pressure CH include:

[0072] S21, when the time required for the secondary pressure of the gas proportional valve to decrease from the maximum secondary pressure PH to the minimum secondary pressure PL is the same as the time required for the fan speed to decrease from the maximum fan speed FH to the minimum fan speed FL, determine the speed change rate of the fan and the pressure change rate of the secondary pressure of the gas proportional valve;

[0073] S22. Control the secondary pressure of the gas proportional valve and the fan speed to start adjusting at the same time according to the speed change rate and the pressure change rate, until the fan speed is adjusted to the flame transfer fan speed FC, and the secondary pressure of the gas proportional valve is adjusted to the flame transfer secondary pressure CH.

[0074] Specifically, during the development process, the maximum speed FH and the minimum speed FL of the fan, as well as the maximum secondary pressure PH and the minimum secondary pressure PL of the gas proportional valve are pre-set, wherein the air-fuel ratio of the maximum speed FH and the maximum secondary pressure PH matches, and the air-fuel ratio of the minimum speed FL and the minimum secondary pressure PL matches. Figure 8 As shown, it takes time ΔT=t3-t1 for the fan to decrease from the highest speed FH to the lowest speed FL. The decreasing speed of the secondary pressure of the gas proportional valve can be reduced by program setting, so that the time required to decrease from the maximum secondary pressure PH to the minimum secondary pressure PL is also ΔT=t3-t1; thereby, during the decrease of the secondary pressure of the gas proportional valve, the air-fuel ratio of the gas water heater is constant in the preset range, and the fan speed and the secondary pressure always keep the air-fuel ratio matched.

[0075] Furthermore, the secondary pressure CH of the fire transmission is set to be greater than the secondary pressure CH′ corresponding to the speed FC of the fire transmission fan according to the mapping relationship P=f(r). Figure 8 As shown, when the secondary pressure drops from the maximum secondary pressure PH to the fire transfer secondary pressure CH, the secondary pressure is maintained at the fire transfer secondary pressure CH and no longer drops; and the fan speed will continue to drop. When the fan speed is about to reach the fire transfer fan speed FC, the secondary pressure CH′ corresponding to the fire transfer fan speed FC according to the mapping relationship P=f(r) is less than the fire transfer secondary pressure CH; that is, when the secondary pressure drops to the fire transfer secondary pressure CH, in the process of the fan speed continuing to drop, the secondary pressure of the gas proportional valve is relatively large, and the flameout phenomenon due to the excessively high fan speed will not occur, which can further improve the fire transfer stability.

[0076] like Fig.11 As shown, in one embodiment, before the step of controlling the target segmented valve corresponding to the target combustion unit to open, it also includes:

[0077] S301, obtaining the time when the fan speed starts to be adjusted;

[0078] S302. Determine the time to control the opening of the target sectional valve according to the time when the fan speed starts to be adjusted and the preset time, so that the time when the target sectional valve is opened is delayed by the preset time compared with the time when the fan speed starts to be adjusted, and the time when the target sectional valve completes opening is no earlier than the time when the fan speed drops to the fire transmission fan speed FC.

[0079] In this embodiment, the moment when the target sectional valve is controlled to open is delayed by a preset time period compared to the moment when the fan speed starts to be adjusted, so that the target sectional valve is opened when the fan speed drops to the fire transfer fan speed FC or later, thereby reducing the risk of blowing out the flame due to excessive fan speed caused by secondary pressure drop at the moment of valve opening.

[0080] For example, Figure 6 As shown, in one embodiment, the time when the fan speed starts to be adjusted from the highest fan speed FH is t1, and the time when the fan speed drops to the fire transfer fan speed FC is t2; after t1 and before t2, at t4 (i.e., t1<t4<t2), the target segmented valve (e.g., the third segmented valve 63) is controlled to open, so that the target segmented valve completes opening at t2, i.e., the time when the valve is completed coincides with the time when the fan speed drops to the fire transfer fan speed FC. For another example, Figure 7 As shown, in another embodiment, the target segmented valve (e.g., the third segmented valve 63) can also be controlled to open at time t5 after time t4 (i.e., t5>t4), so that the target segmented valve completes opening at time t6 (t6>t2), that is, the target segmented valve completes opening at a time later than the time when the fan speed drops to the flame transfer fan speed FC. After the fan speed drops to the flame transfer fan speed FC, the fan speed remains constant, and even if the secondary pressure of the gas proportional valve fluctuates from falling to rising, as long as it is not lower than the secondary pressure threshold of flameout, the flameout will not occur.

[0081] In one embodiment, the step of controlling the opening of the target segmented valve corresponding to the target combustion unit is specifically:

[0082] The target sectional valve is controlled to open when the fan speed drops to the fire transfer fan speed FC; or, the target sectional valve is controlled to open after the fan speed drops to the fire transfer fan speed FC.

[0083] In this embodiment, the target sectional valve is opened when the fan speed drops to the flame transmission fan speed FC or later, which can ensure that the target sectional valve is opened later than the fan speed drops to the flame transmission fan speed FC. This can reduce the risk of the flame being blown out by the excessive fan speed due to the secondary pressure drop generated at the moment of valve opening.

[0084] In order to further eliminate the risk of flameout due to the secondary pressure drop at the moment of valve opening, in one embodiment, the flameout secondary pressure threshold CH' corresponding to the flame transfer fan speed FC min Less than the minimum secondary pressure of the fire transmission CH min , where the minimum secondary pressure of the fire transmission is CH min It is the minimum value of the secondary pressure drop when the target sectional valve is opened.

[0085] Specifically, the flameout secondary pressure threshold and the flame transmission fan speed can be pre-set during the development process. The specific setting method is to measure the minimum value of the flame transmission secondary pressure drop at the moment when the target segment valve is opened as the flame transmission secondary pressure minimum CH min ; Set the speed of the flame-transmitting fan FC, and ensure that the flame-transmitting fan speed FC corresponds to the secondary pressure threshold CH' min Less than the minimum secondary pressure of the fire transmission CH min In this way, since the target sectional valve is opened no earlier than the moment when the fan speed drops to the flame transmission fan speed FC, at the moment when the target sectional valve is opened, the fan speed is kept at a constant flame transmission fan speed FC. Even if the secondary pressure of the gas proportional valve fluctuates downward and then upward, as long as the flame transmission secondary pressure reaches the minimum value CH min Not less than the flameout secondary pressure threshold CH' corresponding to the flameout fan speed FC min , there will be no flameout, thereby eliminating the risk of flameout caused by the secondary pressure drop at the moment of valve opening, thereby further improving the flame transmission reliability and further improving the quality reliability of the gas water heater 100.

[0086] In one embodiment, the average value of the maximum secondary pressure PH and the minimum secondary pressure PL of the gas proportional valve is used as the reference secondary pressure P, and the value of the secondary pressure CH for the fire transmission is within the range of [P±10%]. Specifically, P=(PH+PL) / 2, and the secondary pressure CH for the fire transmission is set within the range of [P±10%]. When the fire transmission is completed, the difference between the secondary pressure of the gas proportional valve rising to the maximum secondary pressure PH and falling to the minimum secondary pressure PL is basically the same.

[0087] Based on the above embodiments, Fig.12 As shown, in one of the embodiments, before the step of receiving the instruction to transmit fire to the target combustion unit, the step also includes:

[0088] S01, determining whether the combustion of the current combustion unit under the current working conditions meets the hot water demand;

[0089] S02. If the hot water demand is not met, the fan speed under the current working condition is adjusted to the maximum fan speed FH, and the secondary pressure of the gas proportional valve is adjusted to the maximum secondary pressure PH;

[0090] S03, judging whether the combustion of the current combustion unit under the adjusted working condition meets the hot water demand;

[0091] S04. If the hot water demand is not met, a command to transfer fire to the target combustion unit is issued.

[0092] Specifically, when the gas water heater 100 is turned on, a smaller fire level may be used for heating; for example, Figure 2 and Figure 3 As shown, when igniting, first open the first segment valve 61, ignite the air-fuel mixture of the 12-15 burner monolith, and realize the combustion of the first combustion unit 41 (12-15 has 4 burner monoliths); the corresponding fan speed under this working condition can be between the maximum fan speed FH and the minimum low fan speed FL, and the corresponding gas proportional valve secondary pressure under this working condition can be between the maximum secondary pressure PH and the minimum secondary pressure PL, as long as the air-fuel ratio is matched. The outlet water temperature can be detected by a temperature sensor and compared with the target hot water temperature set by the user. When the detected outlet water temperature does not reach the target hot water temperature, it indicates that the current combustion unit (such as the first combustion unit 41) does not meet the heat demand under the current working condition. When the hot water demand is not met, the firepower gear can be increased by adjusting the fan speed to the maximum fan speed FH and the secondary pressure of the gas proportional valve to the maximum secondary pressure PH. It should be noted that if in the initial state, the current combustion unit is already burning under the conditions of the highest fan speed FH and the maximum secondary pressure PH, steps S02 and S03 can be omitted.

[0093] It is determined whether the combustion of the current combustion unit (e.g., the first combustion unit 41) meets the hot water demand under the conditions of the highest fan speed FH and the maximum secondary pressure PH; if the hot water demand is not met, the controller 90 issues a command to transfer fire to the target combustion unit (e.g., the second combustion unit 42); then the fire can be transferred by delaying the adjustment of the secondary pressure and / or delaying the opening of the valve in the aforementioned embodiment, thereby realizing the combustion of the first combustion unit 41 and the second combustion unit 42 (12-18, a total of 7 burner single pieces). Continue to determine whether the current combustion unit (e.g., the first combustion unit 41 and the second combustion unit 42) meets the hot water demand under the conditions of the highest fan speed FH and the maximum secondary pressure PH; if the hot water demand is still not met, the controller 90 issues an instruction to transfer the fire to the next target combustion unit (e.g., the third combustion unit 43); then the fire can be transferred in accordance with the method of delaying the adjustment of the secondary pressure and / or delaying the opening of the valve in the aforementioned embodiment, and after the fire transfer is stable, the first segment valve 61 and the second segment valve 62 are closed, so that the third combustion unit 43 (1-11, a total of 11 burner monoliths) can be burned. In this way, by performing combustion in a segmented fire transfer manner, the burner 40 can be adjusted to different firepower levels, thereby meeting different hot water needs of users, and the fire transfer performance is reliable, which can improve the quality reliability of the gas water heater 100.

[0094] It should be noted that the above is a description of a specific embodiment of the present specification. Other embodiments are within the scope of the appended claims. Unless otherwise specified, the above steps S1, S2 and S3 are not limited to a sequential order. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0095] The present invention also provides a control device for a gas water heater 100, comprising:

[0096] A memory, wherein the memory stores a control program of the gas water heater;

[0097] A processor, wherein the processor is used to execute a control program of the gas water heater to implement a control method of the gas water heater 100 as described in any of the above embodiments.

[0098] Specifically, when the control program of the gas water heater stored in the memory is executed by the processor, at least the control method of the gas water heater 100 of any one of the above-mentioned embodiments is implemented. It can be understood that since the control device of the gas water heater 100 of the present invention implements the control method of the gas water heater 100 of any one of the above-mentioned embodiments, the embodiment of the control device of the gas water heater 100 of the present invention includes all the technical solutions of all the embodiments of the control method of the above-mentioned gas water heater 100, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0099] In addition, the present invention also proposes a gas water heater 100, on which the control method of the gas water heater 100 described in any of the above embodiments is used or the control device of the gas water heater 100 described in any of the above embodiments is included. It can be understood that since the present invention uses the control method or control device of the gas water heater 100 of any of the above embodiments on the gas water heater 100, the embodiment of the gas water heater 100 of the present invention includes all technical solutions of all embodiments of the control method or control device of the gas water heater 100, and the technical effects achieved are also exactly the same, which will not be repeated here. Among them, the gas water heater 100 includes but is not limited to a gas water heater or a wall-mounted boiler; the gas water heater can be a strong drum type gas water heater with a fan 70 placed below, or a strong extraction type gas water heater with a fan 70 placed above. The burner 40 of the gas water heater 100 is a segmented burner, which can be two segments, three segments, four segments, etc., which are not specifically limited here.

[0100] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A control method for a gas water heater, characterized in that: The following steps are involved: When receiving the instruction to transmit fire to the target combustion unit, the current fan speed and the current secondary pressure of the gas proportional valve are obtained; Adjust the current fan speed to the flame transfer fan speed FC and adjust the current gas proportional valve secondary pressure to the flame transfer secondary pressure CH; during the adjustment of the gas proportional valve secondary pressure, control the mapping relationship between the gas proportional valve secondary pressure and the fan speed P = f (r) to keep the air-fuel ratio of the gas water heater constant in the preset range, and ensure that the gas proportional valve secondary pressure at any time during the adjustment process is greater than the secondary pressure flameout threshold CH' corresponding to the fan speed at the same time min ; The target segmented valve corresponding to the target combustion unit is controlled to open so that the target combustion unit can burn.

2. The control method of the gas water heater according to claim 1, characterized in that: The steps of adjusting the current fan speed to the flame transfer fan speed FC and adjusting the current gas proportional valve secondary pressure to the flame transfer secondary pressure CH include: Under the condition that the time required for the secondary pressure of the gas proportional valve to decrease from the maximum secondary pressure PH to the minimum secondary pressure PL is the same as the time required for the fan speed to decrease from the maximum fan speed FH to the minimum fan speed FL, determine the speed change rate of the fan and the pressure change rate of the secondary pressure of the gas proportional valve; The secondary pressure of the gas proportional valve is controlled according to the speed change rate and the pressure change rate to start adjusting at the same time as the fan speed, until the fan speed is adjusted to the flame transfer fan speed FC, and the secondary pressure of the gas proportional valve is adjusted to the flame transfer secondary pressure CH.

3. The control method of the gas water heater according to claim 2, characterized in that: The fire transmission secondary pressure CH is set to be greater than the secondary pressure CH' corresponding to the fire transmission fan speed FC according to the mapping relationship P=f(r).

4. The control method of the gas water heater according to claim 1, characterized in that: Before the step of controlling the target segmented valve corresponding to the target combustion unit to open, the method further includes: Get the moment when the fan speed starts to be adjusted; The time for opening the target sectional valve is determined according to the time when the fan speed starts to be adjusted and the preset time, so that the time when the target sectional valve is opened is delayed by the preset time compared with the time when the fan speed starts to be adjusted, and the time when the target sectional valve completes opening is no earlier than the time when the fan speed drops to the fire transmission fan speed FC.

5. The control method of the gas water heater according to claim 1, characterized in that: The steps of controlling the opening of the target segmented valve corresponding to the target combustion unit are specifically as follows: The target sectional valve is controlled to open when the fan speed drops to the fire transfer fan speed FC; or, the target sectional valve is controlled to open after the fan speed drops to the fire transfer fan speed FC.

6. The control method of the gas water heater according to claim 1, characterized in that: The flameout secondary pressure threshold CH' corresponding to the flame transmission fan speed FC min Less than the minimum secondary pressure of the fire transmission CH min , where the minimum secondary pressure of the fire transmission is CH min It is the minimum value of the secondary pressure drop when the target sectional valve is opened.

7. The control method of the gas water heater according to claim 1, characterized in that: The average value of the maximum secondary pressure PH and the minimum secondary pressure PL of the gas proportional valve is taken as the reference secondary pressure P, and the value of the flame transmission secondary pressure CH is within the range of [P±10%].

8. The control method of the gas water heater according to any one of claims 1 to 7, characterized in that: Before the step of receiving the instruction to transmit fire to the target combustion unit, the method further includes: Determine whether the combustion of the current combustion unit meets the hot water demand under the current working conditions; If the hot water demand is not met, the fan speed under the current working condition is adjusted to the maximum fan speed FH, and the secondary pressure of the gas proportional valve is adjusted to the maximum secondary pressure PH; Determine whether the current combustion unit meets the hot water demand under the adjusted working conditions; If the hot water demand is not met, a command is issued to transfer fire to the target combustion unit.

9. A control device for a gas water heater, characterized in that: include: A memory, wherein the memory stores a control program of the gas water heater; A processor, wherein the processor is used to execute the control program of the gas water heater to implement the control method of the gas water heater as described in any one of claims 1 to 8.

10. A gas water heater, characterized in that: The gas water heater uses the control method of the gas water heater according to any one of claims 1 to 8; Or it may include the control device of the gas water heater as claimed in claim 9.

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