Water heater water pump rotating speed control method, device and system
By monitoring and adjusting the water pump speed in real time, the noise and cavitation problems of gas water heaters during peak water usage periods have been solved, achieving stable water pressure and equipment safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGDONG VANWARD NEW ELECTRIC CO LTD
- Filing Date
- 2026-03-17
- Publication Date
- 2026-05-12
AI Technical Summary
When water pressure fluctuates during peak water usage periods, the inlet pressure of the water pump in existing gas water heaters is lower than the saturated vapor pressure, resulting in noticeable noise and cavitation caused by bubble formation.
By monitoring the pump outlet pressure and speed in real time, the pump speed is adjusted to maintain the outlet pressure at or above the corresponding cavitation noise lower limit. When necessary, the pressure recovery threshold and the set pressure range are adjusted to achieve step or continuous adjustment of the speed.
It effectively reduces noise and cavitation, ensures stable water pressure, prevents water heater damage, and extends service life.
Smart Images
Figure CN122015294A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of water heater control technology, and in particular to a method, device and system for controlling the speed of a water heater pump. Background Technology
[0002] To achieve zero-cold-water preheating or pressurization functions, existing gas water heaters install a water pump inside. The pump's operation allows hot water to circulate to the point of use in advance, or ensures a sufficient flow rate during normal water usage. When the pump is running, the water heater typically controls it to operate at a fixed maximum power. However, during peak water usage periods, when water pressure fluctuates, a sudden drop in pressure may occur. If the pump operates at maximum power, the inlet pressure may fall below the saturated vapor pressure, easily causing air bubbles to form and burst, resulting in noticeable abnormal noise. Summary of the Invention
[0003] The first technical problem solved by this invention is to provide a water pump speed control method for water heaters, which can effectively reduce noise and cavitation.
[0004] The second technical problem solved by the present invention is to provide a water heater pump speed control device that can effectively reduce noise and cavitation.
[0005] The third technical problem solved by this invention is to provide a water heater pump speed control system that can effectively reduce noise and cavitation.
[0006] The first technical problem mentioned above is solved by the following technical solution: A method for controlling the speed of a water pump in a water heater, applied to a control motherboard; the method includes: after the water pump starts, acquiring the current water pump outlet pressure and the current water pump speed in real time; if the current water pump outlet pressure is lower than the current lower limit of water pressure corresponding to the current water pump speed that generates cavitation noise, reducing the current water pump speed until the latest current water pump outlet pressure is not lower than the latest current lower limit of water pressure corresponding to the current water pump speed that generates cavitation noise; wherein, the relationship between the lower limit of water pressure and the water pump speed is positively correlated; the rate of change of the water pump outlet pressure with the water pump speed is less than the rate of change of the lower limit of water pressure with the water pump speed.
[0007] Compared with the prior art, the water pump speed control method of the present invention has the following advantages: In the present invention, after the water pump starts, the current water pump outlet pressure and the current water pump speed are acquired in real time. Furthermore, the current water pump speed can be used to determine the current lower limit of water pressure that generates cavitation noise. Then, the judgment of the current water pump outlet pressure and the current lower limit of water pressure is used to identify whether the water pump generates noise and cavitation. When the current water pump outlet pressure is lower than the current lower limit of water pressure, it indicates that the water pump may generate noise and cavitation. Since the relationship between the lower limit of water pressure and the water pump speed is positively correlated, by reducing the current water pump speed, both the water pump outlet pressure and the lower limit of water pressure will decrease. Moreover, the rate of change of the water pump outlet pressure with the water pump speed is less than the rate of change of the lower limit of water pressure with the water pump speed. During the process of reducing the current water pump speed, the latest current water pump outlet pressure will not be lower than the current lower limit of water pressure that generates cavitation noise corresponding to the latest current water pump speed, thereby effectively reducing the generation of noise and cavitation.
[0008] In one embodiment, the method further includes: if the current water pump outlet pressure is not lower than the current lower limit of water pressure corresponding to the current water pump speed that generates cavitation noise, determining whether the current water pump outlet pressure is higher than a pressure recovery threshold; wherein, the pressure recovery threshold is the current lower limit of water pressure plus a specified pressure increment, or a specified multiple of the current lower limit of water pressure; the specified multiple is greater than 1; if not, maintaining the current water pump speed; if yes, adjusting the water pump speed according to the relationship between the current water pump outlet pressure and the set pressure range.
[0009] In one embodiment, the step of adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range includes: increasing the current pump speed if the current pump outlet pressure is less than the lower limit of the set pressure range; decreasing the current pump speed if the current pump outlet pressure is greater than the upper limit of the set pressure range; and maintaining the current pump speed if the current pump outlet pressure is within the set pressure range.
[0010] In one embodiment, the lower limit of the pressure range is the specified pressure minus the first set pressure, and the upper limit is the specified pressure plus the second set pressure; when the current working mode is water boosting mode, the specified pressure is the third set pressure; when the current working mode is not water boosting mode, the specified pressure is the minimum value between the preset upper limit of water pressure and the first pressure value, wherein the first pressure value is the sum of the starting water pressure and the fourth set pressure.
[0011] In one embodiment, before the step of adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range, the method further includes: obtaining the current pump power; determining whether the current pump power is less than or equal to a power threshold; if not, reducing the current pump speed; if yes, continuing to execute the step of adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range.
[0012] In one embodiment, before the step of adjusting the water pump speed based on the relationship between the current water pump outlet pressure and the set pressure range, the method further includes: obtaining the current demand load of the water heater; determining whether the current demand load is less than or equal to the maximum load; if not, reducing the current water pump speed; if the current demand load is not less than or equal to the preset load, maintaining the current water pump speed; if the current demand load is less than or equal to the preset load, continuing to execute the step of adjusting the water pump speed based on the relationship between the current water pump outlet pressure and the set pressure range.
[0013] In one embodiment, before the step of adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range, the method further includes: determining whether the current pump speed has reached the maximum speed; if yes, maintaining the current pump speed; if no, continuing to perform the step of adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range.
[0014] In one embodiment, the pump speed is adjusted using a stepped adjustment method or a continuous adjustment method.
[0015] The second technical problem mentioned above is also solved by the following technical solution: A water heater pump speed control device is applied to a control mainboard. The device includes: a pressure and speed acquisition module for acquiring the current pump outlet pressure and current pump speed in real time after the pump starts; and a speed adjustment module for reducing the current pump speed if the current pump outlet pressure is lower than the current lower water pressure limit corresponding to the current pump speed causing cavitation noise, until the latest current pump outlet pressure is not lower than the latest current lower water pressure limit corresponding to the current pump speed causing cavitation noise. The relationship between the lower water pressure limit and the pump speed is positively correlated; the rate of change of the pump outlet pressure with the pump speed is less than the rate of change of the lower water pressure limit with the pump speed.
[0016] Compared with the prior art, the water pump speed control device of the present invention has the following advantages: In the present invention, the pressure and speed acquisition module acquires the current water pump outlet pressure and the current water pump speed in real time after the water pump starts. The speed adjustment module can determine the current lower limit of water pressure that corresponds to the generation of cavitation noise based on the current water pump speed. Then, it identifies whether the water pump generates noise and cavitation by judging the current water pump outlet pressure and the current lower limit of water pressure. When the current water pump outlet pressure is lower than the current lower limit of water pressure, it indicates that the water pump may generate noise and cavitation. Since the relationship between the lower limit of water pressure and the water pump speed is positively correlated, by reducing the current water pump speed, both the water pump outlet pressure and the lower limit of water pressure will decrease. Moreover, the rate of change of the water pump outlet pressure with the water pump speed is less than the rate of change of the lower limit of water pressure with the water pump speed. During the process of reducing the current water pump speed, the latest current water pump outlet pressure will not be lower than the current lower limit of water pressure that corresponds to the generation of cavitation noise, thereby effectively reducing the generation of noise and cavitation.
[0017] The third technical problem mentioned above is also solved by the following technical solution: A water heater pump speed control system includes a water pump, a water pressure sensor, and a control main board installed in the water heater; the water pressure sensor is installed at the outlet of the water pump and is communicatively connected to the control main board; the water pump is communicatively connected to the control main board; the water pressure sensor is used to detect the current outlet pressure of the water pump in real time after the water pump is turned on and send it to the control main board; the control main board is used to execute the method described in the water heater pump speed control method.
[0018] Compared with the prior art, the water pump speed control system for water heaters described in this invention has the following advantages: The system includes a water pump, a water pressure sensor, and a control mainboard installed in the water heater; the water pressure sensor is installed at the outlet of the water pump and is communicatively connected to the control mainboard; the water pump and the control mainboard are communicatively connected; the water pressure sensor is used to detect the current water pump outlet pressure in real time after the water pump is turned on and send it to the control mainboard; the control mainboard is used to obtain the current water pump outlet pressure and the current water pump speed in real time after the water pump starts, and further determine the current water pressure lower limit corresponding to the generation of cavitation noise through the current water pump speed, and then determine the current water pressure lower limit based on the current water pump outlet pressure and the current water pressure lower limit. The lower limit is used to identify whether the water pump is generating noise and cavitation. When the current water pump outlet pressure is lower than the current lower limit, it indicates that the water pump may be generating noise and cavitation. Since there is a positive correlation between the lower limit and the pump speed, reducing the current pump speed will decrease both the pump outlet pressure and the lower limit. Moreover, the rate of change of the pump outlet pressure with the pump speed is less than the rate of change of the lower limit with the pump speed. During the process of reducing the current pump speed, the latest current pump outlet pressure will not be lower than the current lower limit of water pressure that generates cavitation noise corresponding to the latest current pump speed, thereby effectively reducing the generation of noise and cavitation. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0020] Figure 1 A schematic diagram of a water heater pump speed control provided in this application embodiment; Figure 2 A flowchart of a water heater pump speed control method provided in this application embodiment; Figure 3 A flowchart of another water heater pump speed control method provided in this application embodiment; Figure 4 A flowchart of another water heater pump speed control method provided in this application embodiment; Figure 5 This is a structural block diagram of a water heater pump speed control device provided in an embodiment of this application. Detailed Implementation
[0021] The technical solutions of this application will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0022] The existing water pump control method, which controls the water pump to operate at maximum power, is prone to causing the water pump inlet pressure to drop below the saturated vapor pressure when the water pressure fluctuates during peak water usage periods. This results in the generation and rupture of bubbles, creating noticeable abnormal noise.
[0023] Based on this, embodiments of this application provide a method, apparatus, and system for controlling the speed of a water heater pump, which can effectively reduce noise and cavitation when water pressure drops suddenly during peak water usage periods. To facilitate understanding of this embodiment, a detailed description of the water heater pump speed control method disclosed in this application embodiment will be provided first.
[0024] This application provides a method for controlling the speed of a water heater pump, which is applied to a control motherboard; see also Figure 1 As shown, the control board is communicatively connected to the water pump and water pressure sensor in the water heater; the water pressure sensor is located at the outlet of the water pump; after the water pump starts, the water pressure sensor will detect the current water pump outlet pressure in real time and send the current water pump outlet pressure to the control board so that the control board can adjust the water pump speed according to the current water pump outlet pressure. Figure 2 A flowchart of a water heater pump speed control method provided in this embodiment specifically includes the following steps: Step S202: After the water pump starts, the current water pump outlet pressure and the current water pump speed are obtained in real time. When the water pump is first started, the pump speed is controlled to run at an initial speed, typically set to 5000 r / min. As the pump rotates, a water pressure sensor located at the pump outlet collects the current outlet pressure in real time and transmits it to the control board. In other words, the control board obtains the current outlet pressure of the pump in real time. Furthermore, the control board is communicatively connected to the pump, allowing it to obtain the current pump speed in real time.
[0025] Step S204: If the current water pump outlet pressure is lower than the current water pressure lower limit corresponding to the current water pump speed that generates cavitation noise, reduce the current water pump speed until the latest current water pump outlet pressure is not lower than the latest current water pressure lower limit corresponding to the current water pump speed that generates cavitation noise; wherein, the relationship between the water pressure lower limit and the water pump speed is positively correlated; the rate of change of the water pump outlet pressure with the water pump speed is less than the rate of change of the water pressure lower limit with the water pump speed.
[0026] In practical applications, there is a certain correlation between the pump speed and the corresponding lower limit of water pressure that generates cavitation noise. Each pump speed N has a corresponding lower limit of water pressure PNlim, and this correlation can be experimentally determined and stored in the controller. Generally speaking, the higher the pump speed, the higher the corresponding lower limit of water pressure; the two are directly proportional.
[0027] In this step, after obtaining the current pump outlet pressure and the current pump speed, the current pump speed is first determined according to the correspondence between the pump speed and the lower limit of water pressure. Then, it is further determined whether the current pump outlet pressure is lower than the current lower limit of water pressure. If so, the current pump speed is reduced until the latest current pump outlet pressure is not lower than the current lower limit of water pressure that generates cavitation noise corresponding to the latest current pump speed.
[0028] In the water heater pump speed control method provided in this application embodiment, after the water pump starts, the current water pump outlet pressure and the current water pump speed are acquired in real time. Further, the current water pump speed can be used to determine the current lower limit of water pressure that corresponds to cavitation noise. Then, the determination of the current water pump outlet pressure and the current lower limit of water pressure identifies whether the water pump is generating noise and cavitation. When the current water pump outlet pressure is lower than the current lower limit of water pressure, it indicates that the water pump may be generating noise and cavitation. Since the relationship between the lower limit of water pressure and the water pump speed is positively correlated, reducing the current water pump speed will decrease both the water pump outlet pressure and the lower limit of water pressure. Furthermore, the rate of change of the current water pump outlet pressure with the water pump speed is less than the rate of change of the lower limit of water pressure with the water pump speed. During the process of reducing the current water pump speed, the latest current water pump outlet pressure will not be lower than the current lower limit of water pressure corresponding to the latest current water pump speed that generates cavitation noise, thereby effectively reducing the generation of noise and cavitation.
[0029] This application also provides another method for controlling the speed of a water heater pump, which is implemented based on the above embodiments.
[0030] See Figure 3 As shown, the above method includes the following steps: Step S301: After the water pump starts, the current water pump outlet pressure and the current water pump speed are obtained in real time. Step S302: Determine whether the current water pump outlet pressure is lower than the current water pressure lower limit that generates cavitation noise corresponding to the current water pump speed; If so, proceed to step S303, reduce the current pump speed until the latest current pump outlet pressure is not lower than the current lower limit of water pressure that generates cavitation noise corresponding to the latest current pump speed; wherein, the relationship between the lower limit of water pressure and the pump speed is positively correlated; the rate of change of the pump outlet pressure with the pump speed is less than the rate of change of the lower limit of water pressure with the pump speed.
[0031] If not, proceed to step S304 to determine whether the current water pump outlet pressure is higher than the pressure recovery threshold; wherein, the pressure recovery threshold is the current lower limit of water pressure plus a specified pressure increment, or a specified multiple of the current lower limit of water pressure; the specified multiple is greater than 1; For example, the pressure recovery threshold PNcov can be set to PNlim + ΔP, where ΔP is typically 0.05 MPa to 0.1 MPa; or it can be set to XPNlim, where X is typically 110% to 130%. The pump speed adjustment described above can be achieved using a stepped or continuous adjustment method, which can be designed according to the actual system accuracy requirements. Typically, during pump operation, controlling the corresponding pump speed will cause a slight change in the actual pump speed, approximately 100 to 150 r / min. The impact of speed fluctuations should be avoided during speed adjustment.
[0032] If not, proceed to step S305 to maintain the current pump speed; if yes, proceed to step S306 to adjust the pump speed according to the relationship between the current pump outlet pressure and the set pressure range.
[0033] In one preferred embodiment, the lower limit of the aforementioned set pressure range is the specified pressure minus the first set pressure (e.g., P2 - 0.03 MPa), and the upper limit is the specified pressure plus the second set pressure (e.g., P2 + 0.03 MPa). When the current working mode is water boosting mode, the specified pressure is the third set pressure (P2 = 0.75 MPa). When the current working mode is not water boosting mode (e.g., zero cold water mode), the specified pressure is the minimum value between the preset upper limit water pressure Pmax and the first pressure value (e.g., P2 = min(P0 + P1, Pmax)), where the first pressure value is the sum of the starting water pressure P0 and the fourth set pressure P1.
[0034] That is, if the current pump outlet pressure P is higher than the pressure recovery threshold PNcov, then P is compared with (P2-0.03MPa~P2+0.03MPa) and the pump speed is adjusted to ensure the pressurization effect.
[0035] Furthermore, the steps described above for adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range include the following three scenarios: (1) If the current pump outlet pressure is less than the lower limit of the set pressure range, increase the current pump speed; that is, when P is less than the lower limit of the range (P2-0.03MPa~P2+0.03MPa) P2-0.03MPa, increase the current pump speed.
[0036] (2) If the current pump outlet pressure is greater than the upper limit of the set pressure range, reduce the current pump speed; that is, when P is greater than the upper limit of the range (P2-0.03MPa~P2+0.03MPa) P2+0.03MPa, reduce the current pump speed.
[0037] (3) If the current pump outlet pressure is within the set pressure range, maintain the current pump speed. That is, if P is in the range of (P2-0.03MPa~P2+0.03MPa), maintain the current pump speed.
[0038] It should be noted that if the pressure recovery threshold mentioned above is not designed, and if the pressure is greater than the lower limit of water pressure PNlim, it will be directly compared with (P2-0.03MPa~P2+0.03MPa). Since the lower limit of water pressure PNlim is lower than P2-0.03MPa, the pump speed will be increased, causing the lower limit of water pressure PNlim to rise. Then the current water pressure may be lower than the current lower limit of water pressure PNlim, resulting in repeated adjustments of decreasing and increasing the pump speed.
[0039] In this embodiment, by comparing the current water pump outlet pressure with the pressure recovery threshold, it can quickly and reasonably respond to changes in water pressure. When the water pressure returns to normal (e.g., greater than the upper limit of the range), it actively increases the speed, thus ensuring a reasonable pressurization effect.
[0040] This application also provides another method for controlling the speed of a water heater pump, which is implemented based on the above embodiments.
[0041] See Figure 4 As shown, the entire process includes the following steps: Step 1: After the water pump is started, run the water pump at the initial speed N0, N0=5000r / min.
[0042] Step 2: Determine whether the current water pump outlet pressure P is greater than the lower limit of water pressure PNlim; If no (e.g.) Figure 4 (N), proceed to step 3; if (e.g.) Figure 4 (Y), proceed to step 4; Step 3: The water pump speed decreases. Further determine whether the water pump speed has reached the minimum value; if yes, proceed to step 5; if no, return to step 2. Step 4: Determine if the current pump outlet pressure P is greater than the pressure recovery threshold PNlim+0.05; if not, proceed to step 5; if yes, proceed to step 6. Step 5: Maintain the water pump speed and return to Step 2; Step 6: Obtain the current water pump power; determine if the current water pump power is less than or equal to the power threshold (e.g., ...). Figure 4If the threshold is 400W, proceed to step 3; if yes, proceed to step 7. In this embodiment, the current water pump power is compared with the power threshold. When the current water pump power is greater than the power threshold, the current water pump speed is reduced to ensure that the water pump power does not exceed the power threshold. This can effectively avoid damage to the water heater caused by excessive power, as well as the effects of excessive power such as increased noise, fluctuating water pressure, extremely high power consumption, and unstable hot water circulation.
[0043] In another implementation, when it is determined that the current water pump power is less than or equal to the power threshold, step 10, which compares the current water pump outlet pressure with the set pressure range, can be executed directly. In this implementation, the process of determining the current demand load of the water heater can continue, as in step 7.
[0044] Step 7: Obtain the current demand load Q (T) of the water heater 设 -T 进 ); Determine the current demand load Q(T) 设 -T 进 Is it less than or equal to the maximum load? Figure 4 (PSVmax as shown); if no, proceed to step 3; if yes, proceed to step 8; In this embodiment, the current demand load is compared with the maximum load. When the current demand load is greater than the maximum load, the current water pump speed is reduced. This can keep the current demand load below the maximum load, thereby effectively avoiding the adverse effects on the water heater when the current demand load exceeds the maximum load, and ensuring the normal operation and service life of the water heater.
[0045] Step 8: Determine the maximum load PSVmax and the current demand load Q(T) 设 -T 进 Is the difference greater than or equal to the specified load threshold (e.g.) Figure 4 The 10%PSVmax shown indicates whether the current demand load is less than or equal to the preset load; this preset load is between 80% and 95% of the maximum load. In practical applications, this preset load can be set differently depending on the situation. Optimal values for the preset load include... Figure 4 The value shown is 1 - 10% = 90%; if not, proceed to step 5; if yes, proceed to step 9. If the current demand load is not less than or equal to the preset load, the current pump speed is maintained so that the current demand load is kept within a relatively high reasonable load range; if it is less than or equal to the preset load, the comparison process between the current pump speed and the maximum speed is continued. Alternatively, in another embodiment, the comparison process between the current pump outlet pressure and the set pressure range in step 10 can be directly executed to indirectly increase the current demand load and bring it into a reasonable range.
[0046] Step 9: Determine if the current water pump speed has reached the maximum speed; if yes, proceed to step 5; if no, proceed to step 10. When the current pump speed reaches its maximum speed, maintain the current pump speed to avoid various adverse effects such as increased noise and power consumption caused by the current pump speed exceeding the maximum speed.
[0047] Step 10: Determine the relationship between the current pump outlet pressure P and the set pressure range (P2-0.03~P2+0.03); if P exceeds the range (P2-0.03~P2+0.03), proceed to step 3; if P is below the range (P2-0.03~P2+0.03), proceed to step 11; if P is within the range (P2-0.03~P2+0.03), proceed to step 5. Step 11: The water pump speed increases.
[0048] It should be noted that there is no absolute order between steps 6, 7, and 9 above; their order can be interchanged or adjusted.
[0049] Users typically have a booster pump installed at their home entrance, resulting in relatively high water pressure. Further pressurization by the pump inside the water heater could lead to excessive pressure on the pipes, causing structural failure, rupture, and leakage. To avoid this, the embodiments of this application also include the following method steps: If the current water pump outlet pressure P exceeds the preset upper limit of water pressure Pmax, the water pump speed will be reduced until the water pressure is lower than Pmax. Pmax is the safe pressure of the water heater system, usually between 0.7MPa and 1.0MPa.
[0050] The above methods can avoid excessive water pressure, reduce the peak pressure the system can withstand, and ensure the lifespan of the water heater.
[0051] The water heater pump speed control method provided in this application has the following beneficial effects: 1. Monitor water pressure in real time and adjust the water pump speed to avoid excessive water pressure, reduce the peak pressure that the system can withstand, and ensure the service life of the water heater.
[0052] 2. Reduce the rotation speed when the water pressure is low. During peak water usage periods, the water pressure drops sharply, which can effectively reduce noise and cavitation.
[0053] 3. It responds quickly to changes in water pressure and actively increases speed when the water pressure returns to normal to ensure a reasonable pressurization effect.
[0054] Based on the above method embodiments, this application also provides a water heater pump speed control device, which is applied to the control motherboard; see also Figure 5As shown, the device includes: a pressure and speed acquisition module 52, used to acquire the current water pump outlet pressure and the current water pump speed in real time after the water pump starts; and a speed adjustment module 54, used to reduce the current water pump speed if the current water pump outlet pressure is lower than the current lower limit of water pressure that generates cavitation noise corresponding to the current water pump speed, until the latest current water pump outlet pressure is not lower than the latest current lower limit of water pressure that generates cavitation noise corresponding to the current water pump speed; wherein, the relationship between the lower limit of water pressure and the water pump speed is positively correlated; the rate of change of the water pump outlet pressure with the water pump speed is less than the rate of change of the lower limit of water pressure with the water pump speed.
[0055] Furthermore, the aforementioned speed adjustment module 54 is also used to determine whether the current water pump outlet pressure is higher than the pressure recovery threshold if the current water pump outlet pressure is not lower than the current water pressure lower limit corresponding to the current water pump speed generating cavitation noise; wherein, the pressure recovery threshold is the current water pressure lower limit plus a specified pressure increment, or a specified multiple of the current water pressure lower limit; the specified multiple is greater than 1; if not, maintain the current water pump speed; if yes, adjust the water pump speed according to the relationship between the current water pump outlet pressure and the set pressure range.
[0056] Furthermore, the aforementioned speed adjustment module 54 is also used to increase the current water pump speed if the current water pump outlet pressure is less than the lower limit of the set pressure range; decrease the current water pump speed if the current water pump outlet pressure is greater than the upper limit of the set pressure range; and maintain the current water pump speed if the current water pump outlet pressure is within the set pressure range.
[0057] Furthermore, the lower limit of the aforementioned pressure range is the specified pressure minus the first set pressure, and the upper limit is the specified pressure plus the second set pressure; when the current working mode is water boosting mode, the specified pressure is the third set pressure; when the current working mode is not water boosting mode, the specified pressure is the minimum value between the preset upper limit of water pressure and the first pressure value, wherein the first pressure value is the sum of the starting water pressure and the fourth set pressure.
[0058] Furthermore, the aforementioned speed adjustment module 54 is also used to obtain the current water pump power before the step of adjusting the water pump speed based on the relationship between the current water pump outlet pressure and the set pressure range; determine whether the current water pump power is less than or equal to the power threshold; if not, reduce the current water pump speed; if yes, continue to execute the step of adjusting the water pump speed based on the relationship between the current water pump outlet pressure and the set pressure range.
[0059] Furthermore, the aforementioned speed adjustment module 54 is also used to obtain the current demand load of the water heater; determine whether the current demand load is less than or equal to the maximum load; if not, reduce the current water pump speed; if the current demand load is not less than or equal to the preset load, maintain the current water pump speed; if the current demand load is less than or equal to the preset load, continue to execute the step of adjusting the water pump speed according to the relationship between the current water pump outlet pressure and the set pressure range.
[0060] Furthermore, the aforementioned speed adjustment module 54 is also used to determine whether the current water pump speed has reached the maximum speed; if so, maintain the current water pump speed; if not, continue to execute the step of adjusting the water pump speed according to the relationship between the current water pump outlet pressure and the set pressure range.
[0061] Furthermore, the above-mentioned water pump speed adjustment adopts a step-type adjustment method or a continuous adjustment method.
[0062] The device provided in this application embodiment has the same implementation principle and technical effect as the aforementioned method embodiment. For the sake of brevity, any parts of the device embodiment not mentioned can be referred to the corresponding content in the aforementioned method embodiment.
[0063] Based on the above method embodiments, this application also provides a water heater pump speed control system, see [link to relevant documentation]. Figure 1 As shown, the system includes a water pump, a water pressure sensor, and a control mainboard installed in the water heater; the water pressure sensor is installed at the outlet of the water pump and is communicatively connected to the control mainboard; the water pump is communicatively connected to the control mainboard; the water pressure sensor is used to detect the current water pump outlet pressure in real time after the water pump is turned on and send it to the control mainboard; the control mainboard is used to execute the method described in the aforementioned method embodiments.
[0064] The system provided in this application embodiment has the same implementation principle and technical effects as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the system embodiment can be referred to the corresponding content in the aforementioned method embodiment.
[0065] This application also provides a computer-readable storage medium storing computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions cause the processor to implement the above-described method. For specific implementation details, please refer to the foregoing method embodiments, which will not be repeated here.
[0066] The computer program products of the methods, apparatus, and electronic devices provided in the embodiments of this application include a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods described in the preceding method embodiments. For specific implementations, please refer to the method embodiments, which will not be repeated here.
[0067] Unless otherwise specifically stated, the relative steps, numerical expressions, and values of the components and steps described in these embodiments do not limit the scope of this application.
[0068] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0069] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0070] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the technical scope disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.
Claims
1. A method for controlling the speed of a water heater pump, characterized in that, The method is applied to control a motherboard; the method includes: After the water pump starts, the current water pump outlet pressure and the current water pump speed are obtained in real time. If the current water pump outlet pressure is lower than the current water pressure lower limit that generates cavitation noise corresponding to the current water pump speed, reduce the current water pump speed until the latest current water pump outlet pressure is not lower than the latest current water pressure lower limit that generates cavitation noise corresponding to the current water pump speed. Among them, the relationship between the lower limit of water pressure and the pump speed is positively correlated; the rate of change of the pump outlet pressure with the pump speed is less than the rate of change of the lower limit of water pressure with the pump speed.
2. The method according to claim 1, characterized in that, The method further includes: If the current water pump outlet pressure is not lower than the current lower limit of water pressure corresponding to the current water pump speed that generates cavitation noise, determine whether the current water pump outlet pressure is higher than the pressure recovery threshold; wherein, the pressure recovery threshold is the current lower limit of water pressure plus a specified pressure increment, or a specified multiple of the current lower limit of water pressure; the specified multiple is greater than 1; If not, maintain the current pump speed; If so, adjust the pump speed according to the relationship between the current pump outlet pressure and the set pressure range.
3. The method according to claim 2, characterized in that, The steps for adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range include: If the current pump outlet pressure is less than the lower limit of the set pressure range, increase the current pump speed; if the current pump outlet pressure is greater than the upper limit of the set pressure range, decrease the current pump speed; if the current pump outlet pressure is within the set pressure range, maintain the current pump speed.
4. The method according to claim 2, characterized in that, The lower limit of the set pressure range is the specified pressure minus the first set pressure, and the upper limit is the specified pressure plus the second set pressure; When the current working mode is water pressurization mode, the specified pressure is the third set pressure; When the current working mode is not the water pressurization mode, the specified pressure is the minimum value between the preset water pressure upper limit and the first pressure value, wherein the first pressure value is the sum of the starting water pressure and the fourth set pressure.
5. The method according to claim 2, characterized in that, Before adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range, the following steps are also included: Get the current water pump power; Determine whether the current water pump power is less than or equal to the power threshold; If not, reduce the current water pump speed; If so, continue with the step of adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range.
6. The method according to claim 2, characterized in that, Before adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range, the following steps are also included: Obtain the current demand load of the water heater; Determine whether the current demand load is less than or equal to the maximum load; If not, reduce the current water pump speed; If the current demand load is not less than or equal to the preset load, then maintain the current pump speed; If the current demand load is less than or equal to the preset load, the step of adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range continues.
7. The method according to claim 6, characterized in that, Before adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range, the following steps are also included: Determine whether the current water pump speed has reached the maximum speed; If so, maintain the current water pump speed; If not, continue with the step of adjusting the pump speed based on the relationship between the current pump outlet pressure and the set pressure range.
8. The method according to claim 1, characterized in that, The water pump speed is adjusted using either a stepped adjustment method or a continuous adjustment method.
9. A water pump speed control device for a water heater, characterized in that, The device is used to control the motherboard; the device includes: The pressure and speed acquisition module is used to acquire the current water pump outlet pressure and the current water pump speed in real time after the water pump starts. The speed adjustment module is used to reduce the current water pump speed if the current water pump outlet pressure is lower than the current water pressure lower limit that generates cavitation noise corresponding to the current water pump speed, until the latest current water pump outlet pressure is not lower than the latest current water pressure lower limit that generates cavitation noise corresponding to the current water pump speed. Among them, the relationship between the lower limit of water pressure and the pump speed is positively correlated; the rate of change of the pump outlet pressure with the pump speed is less than the rate of change of the lower limit of water pressure with the pump speed.
10. A water heater pump speed control system, characterized in that, The system includes a water pump, a water pressure sensor, and a control motherboard installed in the water heater; the water pressure sensor is installed at the outlet of the water pump and is communicatively connected to the control motherboard; the water pump is communicatively connected to the control motherboard; the water pressure sensor is used to detect the current water pump outlet pressure in real time after the water pump is turned on and send it to the control motherboard; the control motherboard is used to execute the method as described in any one of claims 1-8.