Control method of water purification system and water purifier

Abstract

This invention discloses a control method for a water purification system and a water purifier, belonging to the field of water purification technology. The control method for the water purification system includes: when the controller receives a pure water intake command, the controller controls the booster pump to start; real-time acquisition of the current water flow rate at the pure water outlet and the remaining service life of the reverse osmosis filter element; and adjustment of the booster pump speed according to the current water flow rate and the remaining service life to maintain the current water flow rate within a set flow range. The water purifier includes a casing, a water purification system, and a controller. The water purification system is housed within the casing, and the controller uses the aforementioned control method to control the water purification system. When adjusting the booster pump speed, the speed is adjusted according to the current water flow rate and the remaining service life to ensure that the booster pump speed matches the lifespan of the reverse osmosis filter element, thereby maintaining a stable current water flow rate.

Description

Technical Field

[0001] This invention relates to the field of water purification technology, and in particular to a control method for a water purification system and a water purifier. Background Technology

[0002] A water purifier is a device that purifies tap water into pure water. The core components of the purification system are a booster pump and a reverse osmosis filter cartridge. The power of the booster pump and the membrane area of ​​the reverse osmosis membrane determine the machine's water flow rate. The greater the power of the booster pump or the larger the membrane area, the greater the water flow rate.

[0003] In existing water purification systems, booster pumps mostly use 24V or 36V DC brushed water pumps. Because the voltage of the booster pump is fixed, its power cannot be automatically adjusted, resulting in a fixed water flow rate. However, in actual use, as the reverse osmosis membrane becomes clogged with impurities, leading to a decrease in water flow rate and unstable water output, resulting in a poor user experience.

[0004] Some water purification systems use variable frequency adjustable booster pumps, adjusting the operating parameters of the booster pump according to the water flow rate. However, they still do not consider the impact of the reverse osmosis membrane's lifespan on the water production rate, resulting in a mismatch between the booster pump's operating parameters and the reverse osmosis membrane's lifespan. Long-term adjustments cannot achieve a stable water flow rate. Summary of the Invention

[0005] The purpose of this invention is to provide a control method for a water purification system and a water purifier, so as to solve the technical problem of unstable water flow rate in existing water purifiers.

[0006] Based on the above concept, the technical solution adopted by this invention is as follows:

[0007] A method for controlling a water purification system, comprising:

[0008] When the controller receives a pure water intake command, it controls the booster pump to start.

[0009] The system obtains the current water flow rate at the pure water outlet in real time and the remaining service life of the reverse osmosis filter element. Based on the current water flow rate and the remaining service life, the speed of the booster pump is adjusted to maintain the current water flow rate within the set flow range.

[0010] Preferably, the remaining service life of the reverse osmosis filter element is determined by:

[0011] Obtain the raw water temperature and the current current of the booster pump;

[0012] The corrected current is obtained by correcting the set current based on the raw water temperature;

[0013] The remaining lifespan of the reverse osmosis filter cartridge is determined by comparing the current current with the corrected current.

[0014] Preferably, the set current is corrected based on the raw water temperature to obtain the corrected current, including:

[0015] The current is set as Im, and the corrected current value is In, where In = k * Im, k is the current correction coefficient and k is a function of the raw water temperature T.

[0016] Preferably, during the adjustment of the booster pump speed, the lower and upper limits of the set flow range are corrected based on the raw water temperature and remaining service life.

[0017] Preferably, the lower limit is set to Q1, and the corrected lower limit is Qm, where Qm = k1 * Q1, k1 is the first flow correction coefficient, and k1 is a function of the raw water temperature T and the remaining service life ts.

[0018] Preferably, if the current outflow rate is less than the first set flow rate, the speed increase range is determined, and the speed of the booster pump is increased based on the speed increase range.

[0019] When determining the increment of rotational speed, the increment of rotational speed is determined based on the difference between the first set flow rate and the current outflow rate, as well as the remaining service life.

[0020] The first set flow rate is the lower limit of the set flow rate range.

[0021] Preferably, when determining the increase, the following are included:

[0022] The lifespan of the reverse osmosis filter cartridge is divided into several lifespan intervals from 0 to 100%, and each lifespan interval has a corresponding amplitude value. The corresponding amplitude value is determined based on the remaining lifespan and is denoted as Δv1.

[0023] The flow difference between the first set flow rate and the current outflow rate is divided into several flow difference intervals. Each flow difference interval has a corresponding amplitude value. The corresponding amplitude value is determined based on the flow difference between the first set flow rate and the current outflow rate and is denoted as Δv2.

[0024] We calculate the weighted sum of Δv1 and Δv2 to determine the magnitude of the increase in the speed of the booster pump each time, denoted as Δv, where Δv = a*Δv1 + b*Δv2, and a and b are constants.

[0025] Preferably, if the current outflow rate is greater than the second set flow rate, the speed of the booster pump is reduced; the reduction in speed each time is a fixed value; wherein, the second set flow rate is the upper limit of the set flow rate range.

[0026] Preferably, during the process of adjusting the speed of the booster pump, the cumulative adjustment time is calculated. If the cumulative adjustment time is greater than or equal to the first set time and the current water flow rate is not within the set flow rate range, the controller will issue the first prompt message.

[0027] A water purifier includes a housing, a water purification system, and a controller. The water purification system is disposed within the housing, and the controller controls the water purification system using the control method described above.

[0028] The beneficial effects of this invention are:

[0029] The control method for the water purification system proposed in this invention involves the controller receiving a pure water intake command, indicating a demand for pure water at the outlet. The controller then activates the booster pump. It continuously monitors the current pure water flow rate and the remaining lifespan of the reverse osmosis filter element. Based on these parameters, the booster pump's speed is adjusted to maintain the current flow rate within a set range. Furthermore, the booster pump's speed is matched to the lifespan of the reverse osmosis filter element to ensure a stable current flow rate. Attached Figure Description

[0030] Figure 1 This is a flowchart of the control method for the water purification system provided in the embodiments of the present invention. Figure 1 ;

[0031] Figure 2 This is a flowchart of the control method for the water purification system provided in the embodiments of the present invention. Figure 2 ;

[0032] Figure 3 This is a flowchart of the control method for the water purification system provided in the embodiments of the present invention. Figure 3 ;

[0033] Figure 4 This is a schematic diagram of a water purifier provided in an embodiment of the present invention.

[0034] In the picture:

[0035] 1. Main water pipe; 2. Domestic water pipe; 3. Pure water pipe; 4. Wastewater pipe; 5. Inlet valve; 6. Pre-filter; 7. Booster pump; 8. Reverse osmosis filter; 9. Post-filter; 10. High-pressure switch; 11. Flow meter; 12. First valve; 13. Second valve; 14. Third valve; 15. First check valve; 16. Second check valve; 17. Third check valve; 18. Flushing pipe. Detailed Implementation

[0036] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0037] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0038] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0039] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0040] See Figures 1 to 4 This invention provides a control method for a water purification system, comprising: when a controller receives a pure water intake command, the controller controls a booster pump 7 to start; real-time acquisition of the current water flow rate at the pure water outlet and the remaining service life of the reverse osmosis filter element 8; and adjusting the speed of the booster pump 7 according to the current water flow rate and the remaining service life to maintain the current water flow rate within a set flow range. When adjusting the speed of the booster pump 7, the speed is adjusted according to the current water flow rate and the remaining service life to ensure that the speed of the booster pump 7 matches the service life of the reverse osmosis filter element 8, thereby maintaining a stable current water flow rate.

[0041] For example, the controller receives instructions in real time, including operating mode instructions and water dispensing instructions; the controller executes different actions according to different instructions. When the controller receives a pure water dispensing instruction, indicating a demand for water at the pure water outlet, the controller controls the booster pump 7 to start to ensure that pure water can be dispensed from the outlet. If the controller does not receive a pure water dispensing instruction, but receives other instructions, such as a filter flushing instruction, the controller executes the corresponding instruction; if the controller receives neither a pure water dispensing instruction nor other instructions, the controller remains in the state of receiving instructions in real time.

[0042] For example, in a mechanical faucet, a high-pressure switch 10 is installed on the pure water pipeline 3. The signal output by the high-pressure switch 10 determines whether there is a demand for pure water. When the high-pressure switch outputs a first signal to the controller, it indicates that the pressure in the pure water pipeline 3 is high and there is no demand for water. When the high-pressure switch 10 outputs a second signal to the controller, it indicates that the pressure in the pure water pipeline 3 has decreased, and the controller controls the booster pump 7 to start based on the second signal. For example, in a touch-sensitive faucet, there are touch buttons. When different buttons are triggered, they represent different water dispensing commands, and the controller controls the booster pump 7 to start based on the commands of the touch buttons.

[0043] The current outlet flow rate of the pure water can be obtained by using an existing flow meter 11 to monitor the flow rate in real time. For example, the flow meter 11 is electrically connected to the controller, and the flow meter 11 transmits the monitored outlet flow rate to the controller.

[0044] When adjusting the speed of booster pump 7, the current water flow rate at the pure water outlet is re-acquired each time the speed of booster pump 7 is adjusted, and it is determined whether the current water flow rate is within the set flow rate range. If it is, booster pump 7 maintains the current speed; otherwise, the speed of booster pump 7 is adjusted.

[0045] The set flow rate range has a lower limit and an upper limit. The first set flow rate is the lower limit of the set flow rate range, and the second set flow rate is the upper limit of the set flow rate range. The set flow rate range can be determined through multiple experiments based on different gallon counts of the machine.

[0046] Adjusting the speed of booster pump 7 according to the current water flow rate and remaining service life includes: if the current water flow rate is less than the first set flow rate, determining the speed increase range and increasing the speed of booster pump 7 based on the speed increase range; when determining the speed increase range, determining the speed increase range each time based on the flow rate difference between the first set flow rate and the current water flow rate and the remaining service life.

[0047] If the current outflow rate is less than the first set flow rate, it means that the current outflow rate is low and the speed of the booster pump 7 needs to be increased. However, the increase in speed is not a fixed value. Instead, it is determined based on the difference between the first set flow rate and the current outflow rate, as well as the remaining service life. This fully considers the actual working conditions and makes the increase in speed of the booster pump 7 more in line with reality, so as to quickly and accurately adjust the current outflow rate to the set flow rate range.

[0048] When determining the increase range, the following steps are taken: the service life of the reverse osmosis filter element 8 is divided into several service life intervals from 0 to 100%, each service life interval has a corresponding range value, and the corresponding range value is determined based on the remaining service life and recorded as Δv1; the flow difference between the first set flow rate and the outlet flow rate is divided into several flow difference intervals, each flow difference interval has a corresponding range value, and the corresponding range value is determined based on the flow difference between the first set flow rate and the current outlet flow rate and recorded as Δv2; Δv1 and Δv2 are weighted and calculated to determine the increase range of the speed of the booster pump 7 each time, recorded as Δv, where Δv = a*Δv1 + b*Δv2, and a and b are constants.

[0049] Therefore, based on the flow difference between the first set flow rate and the current outlet flow rate, and the remaining service life, the increment of the rotational speed is determined for each iteration, fully considering the influence of both the flow difference and the remaining service life on the increase in the rotational speed of the booster pump 7. A larger flow difference results in a larger increase, while a larger remaining service life results in a smaller increase. Therefore, multiple sets of data are obtained through repeated experiments to fit and obtain the specific values ​​of a and b. The fitting mentioned in this embodiment can be performed using current data processing software, such as Origin software; the fitting principle will not be elaborated upon here.

[0050] If, during the process of increasing the speed of booster pump 7, the speed of booster pump 7 equals the maximum speed value, and the current outlet water flow is less than the first set flow rate, the controller will issue a second prompt message. If the speed of booster pump 7 has been increased to the maximum speed value, but the current outlet water flow is still lower than the first set flow rate, i.e., lower than the lower limit of the set flow rate range, there may be insufficient water pressure, severe clogging of the reverse osmosis filter element 8 or other filter elements, or other malfunctions. The controller will issue a second prompt message to facilitate timely action by the user.

[0051] The speed of booster pump 7 is adjusted based on the current outlet flow rate and its remaining service life. This includes: if the current outlet flow rate is greater than the second set flow rate, the speed of booster pump 7 is reduced; the reduction in speed is constant each time. If the current outlet flow rate is greater than the second set flow rate, it indicates a large outlet flow rate, requiring a reduction in the speed of booster pump 7. The reduction in speed can also be constant each time. Since the remaining service life of the reverse osmosis filter element 8 has little impact on the deceleration of booster pump 7, setting the reduction to a constant value simplifies the adjustment process.

[0052] For example, each time the speed of the booster pump 7 is increased, the current water flow rate at the pure water outlet is reacquired, and it is determined whether the current water flow rate is within the set flow rate range. If so, the booster pump 7 maintains the current speed; otherwise, it is determined whether the speed of the booster pump 7 is equal to the maximum speed value.

[0053] If the speed of booster pump 7 is equal to the maximum speed, the controller determines whether the current water flow rate is less than the first set flow rate or greater than the second set flow rate based on the newly acquired pure water outlet current flow rate. If the current water flow rate is less than the first set flow rate, the controller issues a second prompt message; if the current water flow rate is greater than the second set flow rate, the speed of booster pump 7 is reduced.

[0054] In some embodiments, during the adjustment of the speed of the booster pump 7, the adjustment time is accumulated. If the accumulated adjustment time is greater than or equal to a first set time and the current water flow rate is not within the set flow rate range, the controller issues a first prompt message. If the accumulated adjustment time is greater than or equal to the first set time and the current water flow rate is not within the first set flow rate range, it indicates that the adjustment has been in place for a relatively long time, but the water flow rate still cannot be maintained within the set flow rate range. This may indicate that the booster pump 7 is damaged, the reverse osmosis filter element 8 or other filter elements are severely clogged, or there may be other malfunctions. In this case, the controller issues a first prompt message to facilitate timely action by the user.

[0055] The remaining service life of the reverse osmosis filter element 8 can be determined based on its usage time. For example, the cumulative usage time of the reverse osmosis filter element 8 shows an inverse relationship between usage time and remaining service life; the longer the usage time, the shorter the remaining service life. Therefore, by conducting multiple experiments, a one-to-one correspondence between usage time and remaining service life can be established, and the remaining service life can be obtained based on the usage time.

[0056] In this embodiment, obtaining the remaining service life of the reverse osmosis filter element 8 includes: obtaining the raw water temperature and the current current of the booster pump 7; correcting the set current based on the raw water temperature to obtain a corrected current; and comparing the current current with the corrected current to determine the remaining service life of the reverse osmosis filter element 8. Typically, the current of the booster pump 7 is inversely proportional to the remaining service life of the reverse osmosis filter element 8; the higher the current current of the booster pump 7, the shorter the remaining service life of the reverse osmosis filter element 8. This embodiment not only reflects the remaining service life of the reverse osmosis filter element 8 through the current current of the booster pump 7, but also fully considers the influence of temperature on the reverse osmosis filter element 8, correcting the set current based on the raw water temperature to make the corrected current closer to the actual operating conditions, thus obtaining a more accurate remaining service life.

[0057] The lifespan of the reverse osmosis filter element 8 is divided into several lifespan intervals from 0 to 100%. The number of lifespan intervals can be set according to actual needs. The more lifespan intervals there are, the more accurate the calculation results will be. For example, the four lifespan intervals of the reverse osmosis filter element 8 are (0, s1%), (s1%, s2%), (s2%, s3%), and (s3%, 100%). The values ​​of s1, s2, and s3 can be set according to actual needs, for example, 10, 40, and 70, respectively. Then, the four lifespan intervals of the reverse osmosis filter element 8 are (0, 10%), (10%, 40%), (40%, 70%), and (70%, 100%).

[0058] As mentioned above, the current of the booster pump 7 is inversely proportional to the remaining service life of the reverse osmosis filter element 8. Based on different gallons of the entire unit, through multiple experiments, with the raw water temperature remaining constant, the current of the booster pump 7 was recorded throughout the entire lifespan of the reverse osmosis filter element 8. The number of current intervals is equal to the number of lifespan intervals. Based on the upper and lower limits of the lifespan intervals, and using the experimentally recorded data, the current of the booster pump 7 is divided into several current intervals from Imin to Imax. For example, the four current intervals of the booster pump 7 are [Imin, I1), [I1, I2), [I2, Imax), and [Imax, +∞). The values ​​of Imin, I1, I2, and Imax can be set according to actual needs. For example, the four current intervals of the booster pump 7 can be [1, 3), [3, 5), [5, 7), and [7, +∞), with the unit of current being amperes.

[0059] Correspondingly, if the current current of the booster pump 7 is greater than or equal to Imax, the remaining service life of the reverse osmosis filter element 8 is less than s1%, and the user needs to be reminded to replace the filter element in time. If the current current of the booster pump 7 is greater than or equal to I2 and less than Imax, the remaining service life of the reverse osmosis filter element 8 is greater than s1% and less than or equal to s2%; if the current current of the booster pump 7 is greater than or equal to I1 and less than I2, the remaining service life of the reverse osmosis filter element 8 is greater than s2% and less than or equal to s3%; if the current current of the booster pump 7 is greater than or equal to Imin and less than I1, the remaining service life of the reverse osmosis filter element 8 is greater than s3% and less than or equal to 100%.

[0060] The set current is corrected based on the raw water temperature to obtain the corrected current. This includes: a set current of Im, and a corrected current of In, where In = k * Im, and k is the current correction coefficient, a function of the raw water temperature T. Therefore, the set current is corrected using the current correction coefficient k, which corrects the upper and lower limits of each current range to obtain the corresponding corrected current, i.e., the corrected current ranges.

[0061] Correspondingly, after correcting the set current using the current correction coefficient k, the four corrected current ranges of the booster pump 7 are [k*Imin, k*I1), [k*I1, k*I2), [k*I2, k*Imax), and [k*Imax, +∞). Correspondingly, if the current of the booster pump 7 is greater than or equal to k*Imax, the remaining service life of the reverse osmosis filter element 8 is less than s1%, and an alarm device can be triggered to remind the user to replace the reverse osmosis filter element 8 in time; if the current of the booster pump 7 is greater than or equal to k*I2 and less than k*Imax, the remaining service life of the reverse osmosis filter element 8 is greater than s1% and less than or equal to s2%; if the current of the booster pump 7 is greater than or equal to k*I1 and less than k*I2, the remaining service life of the reverse osmosis filter element 8 is greater than s2% and less than or equal to s3%; if the current of the booster pump 7 is greater than or equal to k*Imin and less than k*I1, the remaining service life of the reverse osmosis filter element 8 is greater than s3% and less than or equal to 100%.

[0062] Therefore, by calculating the current correction coefficient k based on the raw water temperature and comparing the current of the booster pump 7 with the correction current, the remaining service life of the reverse osmosis filter element 8 can be obtained. The smaller the interval division, the more accurate the remaining service life of the reverse osmosis filter element 8 will be.

[0063] For example, k = AB * T, where A and B are constants. The specific values ​​of A and B can be obtained by fitting multiple sets of raw water temperature and current data from experiments. It is understood that k can be a linear function of temperature or other functions; the appropriate function can be selected based on the specific data. For example, k = 1.5 - 0.02 * T, where T represents the raw water temperature in °C.

[0064] For a single machine, the set flow rate range is not absolutely fixed. As the machine is used for longer periods, the reverse osmosis filter element 8 becomes increasingly clogged, and the set flow rate range should be adjusted accordingly. In addition, the influence of raw water temperature on the permeate rate of the reverse osmosis filter element 8 can also cause a mismatch between the fixed set flow rate range and the actual operating conditions of the entire machine.

[0065] In this embodiment, during the process of adjusting the speed of the booster pump 7, the lower and upper limits of the set flow range are corrected based on the raw water temperature and remaining service life.

[0066] For example, a lower limit value is set to Q1, and a corrected lower limit value is set to Qm, where Qm = k1 * Q1, and k1 is the first flow correction coefficient, which is a function of the raw water temperature T and the remaining service life ts. Therefore, the set lower limit value Q1 is corrected using the first flow correction coefficient k1 to make it more consistent with actual operating conditions. Since k1 is a function of the raw water temperature T and the remaining service life ts, multiple sets of data can be obtained from multiple experiments, and the result can be calculated through fitting.

[0067] For example, an upper limit value is set to Q2, and a corrected upper limit value is set to Qn, where Qn = k2 * Q2, and k2 is a second flow correction coefficient that is a function of the raw water temperature T and the remaining service life ts. Therefore, the lower limit value Q2 is corrected using the second flow correction coefficient k2 to make it more consistent with actual operating conditions. Since k2 is a function of the raw water temperature T and the remaining service life ts, multiple sets of data can be obtained from various experiments, and the result can be calculated through fitting.

[0068] This invention also provides a water purifier, including a housing, a water purification system, and a controller. The water purification system is disposed inside the housing, and the controller controls the water purification system using the control method described above.

[0069] The water purification system includes a main pipeline 1, a domestic water pipeline 2, a pure water pipeline 3, and a wastewater pipeline 4. The main pipeline 1 is equipped with an inlet valve 5 and a pre-filter 6. One end of the domestic water pipeline 2 is connected to the downstream of the pre-filter 6, and the other end is used to discharge domestic water. The pure water pipeline 3 is equipped with a booster pump 7, a reverse osmosis filter 8, a post-filter 9, a high-pressure switch 10, and a flow meter 11. A first valve 12 is installed between the booster pump 7 and the reverse osmosis filter 8. A first check valve 15 is installed between the reverse osmosis filter 8 and the post-filter 9. A second check valve 16 is installed between the post-filter 9 and the high-pressure switch 10. One end of the wastewater pipeline 4 is connected to the wastewater outlet of the reverse osmosis filter 8. A second valve 13 is installed on the wastewater pipeline 4, and the other end is used to discharge wastewater.

[0070] The water purification system also includes a flushing pipe 18, one end of which is connected to the downstream of the second check valve 16. A third check valve 17 and a third valve 14 are sequentially installed on the flushing pipe 18. The other end of the wastewater pipe 4 is connected to the upstream of the booster pump 7.

[0071] The water purification system also includes a temperature sensor, which is installed on the main pipeline 1 to obtain the raw water temperature. The booster pump 7, flow meter 11, and temperature sensor are all electrically connected to the controller.

[0072] The opening and closing of the domestic water outlet and the purified water outlet can be controlled by buttons on the casing. For example, pressing the first button opens the purified water outlet and allows purified water to flow out; pressing the first button again closes the purified water outlet. Pressing the second button opens the domestic water outlet and allows domestic water to flow out; pressing the second button again closes the domestic water outlet.

[0073] For example, when the user presses the first button, the controller receives a pure water intake command and controls the booster pump 7 to start; it obtains the current water flow rate of the pure water outlet in real time, as well as the raw water temperature and the current current of the booster pump 7; it corrects the set current according to the raw water temperature to obtain a corrected current; and it compares the current current with the corrected current to determine the remaining service life of the reverse osmosis filter element 8.

[0074] If the current outflow rate is less than the first set flow rate, the increment of the rotation speed is determined based on the difference between the first set flow rate and the current outflow rate, as well as the remaining service life; and the rotation speed of the booster pump 7 is increased based on the increment of the rotation speed.

[0075] If the current outflow rate is greater than the second set flow rate, the speed of the booster pump 7 will be reduced; the reduction in speed each time is a fixed value.

[0076] If the current outflow rate is greater than or equal to the first set flow rate and less than or equal to the second set flow rate, the booster pump 7 will maintain the current speed.

[0077] Each time the speed of the booster pump 7 is adjusted, the current water flow rate at the pure water outlet is retrieved again. It is then determined whether the current water flow rate is within the set flow rate range. If so, the booster pump 7 maintains the current speed; otherwise, the speed of the booster pump 7 is adjusted according to the current water flow rate and the remaining service life to ensure that the current water flow rate is maintained within the set flow rate range.

[0078] The above embodiments merely illustrate the basic principles and characteristics of the present invention. The present invention is not limited to the above embodiments. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A control method for a water purification system, characterized in that, include: When the controller receives a pure water intake command, it controls the booster pump to start. The system obtains the current water flow rate at the pure water outlet in real time and the remaining service life of the reverse osmosis filter element. Based on the current water flow rate and the remaining service life, the speed of the booster pump is adjusted to maintain the current water flow rate within the set flow range.

2. The control method for the water purification system according to claim 1, characterized in that, To determine the remaining lifespan of the reverse osmosis filter cartridge, including: Obtain the raw water temperature and the current current of the booster pump; The corrected current is obtained by correcting the set current based on the raw water temperature; The remaining lifespan of the reverse osmosis filter cartridge is determined by comparing the current current with the corrected current.

3. The control method for the water purification system according to claim 2, characterized in that, The corrected current is obtained by correcting the set current based on the raw water temperature, including: The current is set as Im, and the corrected current value is In, where In = k * Im, k is the current correction coefficient and k is a function of the raw water temperature T.

4. The control method for the water purification system according to claim 1, characterized in that, During the adjustment of the booster pump speed, the lower and upper limits of the set flow range are corrected based on the raw water temperature and remaining service life.

5. The control method for the water purification system according to claim 4, characterized in that, The lower limit is set to Q1, and the corrected lower limit is Qm, where Qm = k1 * Q1, k1 is the first flow correction coefficient, and k1 is a function of the raw water temperature T and the remaining service life ts.

6. The control method for the water purification system according to claim 1, characterized in that, If the current outflow rate is less than the first set flow rate, the speed increase range is determined, and the speed of the booster pump is increased based on the speed increase range. When determining the increment of rotational speed, the increment of rotational speed is determined based on the difference between the first set flow rate and the current outflow rate, as well as the remaining service life. The first set flow rate is the lower limit of the set flow rate range.

7. The control method for the water purification system according to claim 6, characterized in that, When determining the magnitude of the increase, the following should be included: The lifespan of the reverse osmosis filter cartridge is divided into several lifespan intervals from 0 to 100%, and each lifespan interval has a corresponding amplitude value. The corresponding amplitude value is determined based on the remaining lifespan and is denoted as Δv1. The flow difference between the first set flow rate and the current outflow rate is divided into several flow difference intervals. Each flow difference interval has a corresponding amplitude value. The corresponding amplitude value is determined based on the flow difference between the first set flow rate and the current outflow rate and is denoted as Δv2. We calculate the weighted sum of Δv1 and Δv2 to determine the magnitude of the increase in the speed of the booster pump each time, denoted as Δv, where Δv = a*Δv1 + b*Δv2, and a and b are constants.

8. The control method for the water purification system according to claim 1, characterized in that, If the current outflow rate is greater than the second set flow rate, the speed of the booster pump will be reduced; the reduction in speed each time is a fixed value; where the second set flow rate is the upper limit of the set flow rate range.

9. The control method for the water purification system according to any one of claims 1-8, characterized in that, During the adjustment of the booster pump speed, the cumulative adjustment time is recorded. If the cumulative adjustment time is greater than or equal to the first set time and the current outflow rate is not within the set flow rate range, the controller will issue the first prompt message.

10. A water purifier, characterized in that, The device includes a housing, a water purification system, and a controller. The water purification system is disposed within the housing, and the controller controls the water purification system using the control method of the water purification system according to any one of claims 1-9.

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