Control method, control device, readable storage medium, water pump and air supply device

Abstract

The invention relates to the technical field of pumps, and discloses a control method, a control device, a readable storage medium, a water pump and an air supply device.The method comprises the following steps that the actual rotating speed r0 of the water pump is obtained; judging whether the actual rotating speed r0 is equal to the rated rotating speed r or not; if not, the PWM real-time duty ratio t of the water pump is controlled to be increased or decreased by X, so that the actual rotating speed r0 of the water pump is adjusted. When the actual rotating speed r0 of the water pump is not equal to the rated rotating speed r, the PWM real-time duty ratio t of the water pump is controlled to be increased or decreased by X, so that the actual rotating speed r0 of the water pump is adjusted, the actual rotating speed r0 of the water pump is closer to or equal to the rated rotating speed r, stability and consistency of water flow of the water pump are guaranteed, and water flow fluctuation is reduced; therefore, the user experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of pumps, and in particular to a control method, a control device, a readable storage medium, a water pump and an air supply device. Background Art

[0002] Submersible pumps can work underwater and can be used to pump and transport groundwater, rainwater, wastewater and other liquids. For example, when used in air supply devices such as evaporative cooling fans, the submersible pump is directly immersed in the bottom of the water tank, and the water level needs to completely cover the surface of the submersible pump. The submersible pump is used to pump water to the top of the wet curtain and pour it down. The wind passes through the wet curtain and uses the principle of water evaporation and heat absorption to achieve a cooling effect.

[0003] Existing submersible pumps are prone to stalling and have weak anti-stalling capabilities, which causes the water flow from the submersible pump to the wet curtain to fluctuate, affecting the user experience. Summary of the invention

[0004] In view of this, the present invention provides a control method, a control device, a readable storage medium, a water pump and an air supply device to solve the problem in the prior art that the submersible pump is prone to stalling and has weak anti-stalling ability, which causes the water flow pumped from the submersible pump to the wet curtain to fluctuate.

[0005] A first aspect of the present invention provides a control method for controlling a water pump, the control method comprising the following steps:

[0006] Obtaining the actual rotation speed r0 of the water pump;

[0007] Determine whether the actual speed r0 of the water pump is equal to the rated speed r;

[0008] If not, the PWM real-time duty cycle t of the water pump is controlled to increase or decrease by ΔX to adjust the actual rotation speed r0 of the water pump.

[0009] The control method of the present application, when the actual speed r0 of the water pump is not equal to the rated speed r, controls the PWM real-time duty cycle t of the water pump to increase or decrease △X, so as to adjust the actual speed r0 of the water pump, so that the actual speed r0 of the water pump is closer to or equal to the rated speed r, thereby ensuring the stability and consistency of the water flow of the water pump, reducing water flow fluctuations, and thus improving the user experience.

[0010] In some embodiments, the PWM real-time duty cycle t of the water pump is controlled to increase or decrease by ΔX, and ΔX satisfies the following relationship:

[0011] △X=|(r / r0)t-t|

[0012] t0=(r / r0)×t

[0013] Wherein, t0 is the PWM rated duty cycle of the water pump, and ΔX is the absolute value of the difference between the PWM rated duty cycle of the water pump and the PWM real-time duty cycle of the water pump.

[0014] Beneficial effect: In the above relationship, r0, r, t0 are all known parameters. △X and t can be calculated through the above relationship. According to △X, the PWM real-time duty cycle t of the water pump can be quickly adjusted to make the PWM real-time duty cycle t of the water pump equal to the PWM rated duty cycle, thereby ensuring that the actual speed r0 of the water pump is equal to the rated speed r, so that the water pump always runs at the rated speed r, ensuring the stability of the water flow of the water pump, reducing water flow fluctuations, and thus improving user experience.

[0015] It can be understood that when the water pump is operating normally, the actual speed of the water pump is equal to the rated speed. When there are more impurities in the water, the actual speed of the water pump is lower than the rated speed due to the increase in load. When a large number of bubbles are generated in the water, or the water level is too low and there is a shortage of water, the actual speed of the water pump is higher than the rated speed due to the reduction in load. Based on the above-mentioned situation where the actual speed is not equal to the rated speed, the present application can adjust the actual speed r0 of the water pump by adjusting the PWM real-time duty cycle t of the water pump to make the actual speed r0 equal to the rated speed r, thereby realizing the functions of constant speed and constant flow of the water pump, and improving the situation where the water flow fluctuates and is unstable due to dirty blockage.

[0016] In some embodiments, after the step of controlling the PWM real-time duty cycle t of the water pump to increase or decrease ΔX, the step further includes:

[0017] Determine whether the actual speed r0 of the water pump after adjustment is equal to the rated speed r;

[0018] If not, the PWM real-time duty cycle t of the water pump is controlled to increase or decrease by X, and the actual speed r0 of the water pump is monitored until the actual speed r0 of the water pump is equal to the rated speed r.

[0019] Beneficial effect: The above steps can eliminate the error after the initial adjustment, avoid the situation where the actual speed r0 of the water pump after adjustment is still not equal to the rated speed r, and ensure the accuracy of the adjustment. Specifically, when it is determined that the actual speed r0 of the water pump after adjustment is not equal to the rated speed r, the PWM real-time duty cycle t of the water pump is further controlled to increase or decrease by X, and the actual speed r0 of the water pump is monitored until the actual speed r0 of the water pump is equal to the rated speed r, thereby ensuring that the water pump always runs at the rated speed r.

[0020] In some embodiments, the step of monitoring the actual speed r0 of the water pump until the actual speed r0 of the water pump is equal to the rated speed r comprises:

[0021] Determine whether the actual speed r0 of the water pump is equal to the rated speed r;

[0022] If not, control the PWM real-time duty cycle t of the water pump to continue to increase or decrease by X, and continue to judge whether the adjusted actual speed r0 is equal to the rated speed r, and repeat this cycle until the actual speed r0 of the water pump is equal to the rated speed r.

[0023] Beneficial effect: When it is determined that the actual speed r0 of the water pump after adjustment is not equal to the rated speed r, the PWM real-time duty cycle t of the water pump is controlled to continue to increase or decrease by X, and continue to determine whether the actual speed r0 after adjustment is equal to the rated speed r, and repeat this cycle until the actual speed r0 of the water pump is equal to the rated speed r. By adjusting the PWM real-time duty cycle t of the water pump by an amplitude of X each time, when the actual speed r0 of the water pump after adjustment is not equal to the rated speed r, the PWM real-time duty cycle t of the water pump is returned to continue to increase or decrease by X until the actual speed r0 of the water pump is equal to the rated speed r, and the small amplitude multiple adjustment judgments of the actual speed r0 of the water pump are realized, avoiding the situation where the actual speed r0 and the rated speed r are difficult to match due to the single adjustment amplitude being too large.

[0024] In some embodiments, if not, controlling the PWM real-time duty cycle t of the water pump to increase or decrease by X includes:

[0025] Based on the fact that the actual speed r0 is less than the rated speed r, the PWM real-time duty cycle t of the water pump is controlled to increase by X, so as to increase the actual speed r0 of the water pump;

[0026] Based on the fact that the actual speed r0 is greater than the rated speed r, the PWM real-time duty cycle t of the water pump is controlled to decrease by X, so as to reduce the actual speed r0 of the water pump.

[0027] Beneficial effect: Through the above steps, when the actual speed r0 of the water pump is less than or greater than the rated speed r, the PWM real-time duty cycle t of the water pump can be increased or decreased to increase or decrease the actual speed r0 of the water pump to keep it equal to the rated speed r, thereby ensuring the water flow stability of the water pump.

[0028] In some embodiments, 0<X≤20%, and the value of X increased or decreased each time is equal.

[0029] Beneficial effect: X is limited to 0-20%, so that the PWM real-time duty cycle t of the water pump increases or decreases by 0-20% each time, and the X value increased or decreased each time is equal, that is, the adjustment amplitude is equal, so that the actual speed r0 of the water pump increases or decreases proportionally within a certain range, ensuring the adjustment accuracy.

[0030] In some embodiments, X is 1%.

[0031] Beneficial effect: X is set to 1%, so that the adjustment range is at a smaller level, so that the actual speed r0 of the water pump has more value points, which is easier to match with the rated speed r of the water pump, and the adjustment accuracy is improved.

[0032] In some embodiments, in the step of controlling the PWM real-time duty cycle t of the water pump to increase or decrease by ΔX, the PWM real-time duty cycle t of the water pump is adjusted by adjusting the voltage U input to the water pump.

[0033] Beneficial effect: By adjusting the water input voltage U, the PWM real-time duty cycle t is adjusted, and then the actual speed r0 of the water pump is adjusted, which is convenient for adjustment. For example, increasing the water pump input voltage U can increase the PWM real-time duty cycle t, and conversely, reducing the water pump input voltage U can reduce the PWM real-time duty cycle t.

[0034] A second aspect of the present invention provides a control device, which is used to implement the control method of the present invention. The control device includes an acquisition module, a judgment module and an adjustment module. The acquisition module is used to obtain the actual speed r0 of the water pump, the judgment module is used to judge whether the actual speed r0 of the water pump is equal to the rated speed r, and the adjustment module is used to adjust the PWM real-time duty cycle t of the water pump to increase or decrease △X.

[0035] Beneficial effects: Since the control device of the present invention is used to implement the control method of the present invention, the control device of the present invention has the same technical effects as the control method, which will not be described in detail herein.

[0036] A third aspect of the present invention provides a readable storage medium, wherein the readable storage medium stores computer instructions, and when the computer instructions are executed, the control method of the present invention is executed.

[0037] Beneficial effect: Since the computer instructions stored in the readable storage medium of the present invention execute the control method of the present invention when they are executed, the readable storage medium of the present invention has the same technical effect as the control method, which will not be repeated here.

[0038] A fourth aspect of the present invention provides a water pump, which is controlled by the control method of the present invention. The water pump includes a pump casing, an impeller assembly, a speed detection element and a control main board. The pump casing has a water inlet and a water outlet. The impeller assembly is arranged inside the pump casing, and the impeller assembly is located between the water inlet and the water outlet. The speed detection element is used to detect the actual speed of the impeller assembly. The control main board is electrically connected to the speed detection element. The control main board can control the PWM real-time duty cycle of the water pump to increase or decrease △X to adjust the actual speed of the water pump.

[0039] Beneficial effect: When the water pump of the present application is working, water flows into the water pump from the water inlet, and is transported to the water outlet and discharged from the water pump through the rotation of the impeller assembly. When the speed detection element detects that the actual speed of the impeller assembly is not equal to the rated speed, the control main board increases or decreases △X by adjusting the PWM real-time duty cycle of the water pump, so as to adjust the actual speed of the impeller assembly to make it equal to the rated speed, ensure that the water pump always runs at the rated speed, realize the function of constant speed and constant flow of the water pump, and improve the situation of water flow fluctuation caused by dirty blockage in the water pump.

[0040] In some embodiments, the rotation speed detection element is a photoelectric encoder.

[0041] Beneficial effect: Setting the speed detection element as a photoelectric encoder can achieve fine control, and the photoelectric encoder has a simple structure and is easy to maintain.

[0042] In some embodiments, the impeller assembly includes an axle, an impeller and a ballast cover, the axle is rotatably disposed in the pump casing, the impeller is fixedly sleeved on the axle, the impeller cover is disposed at the water inlet of the pump casing, and the impeller cover has a water outlet.

[0043] Beneficial effect: When the wheel shaft rotates, it drives the impeller to rotate synchronously. The impeller rotates and beats the water to the outlet. The impeller cover has the function of filtering large particles of impurities. Impurities with a particle size larger than the water outlet are blocked outside the water pump, thereby alleviating the problem of dirty and blocked water pumps.

[0044] In some embodiments, the water pump further comprises a front cover, wherein the front cover is fixedly connected to the pump casing, the front cover is disposed on the blade compartment cover, and the front cover can perform primary filtration on the water flowing into the pump casing.

[0045] Beneficial effect: The front cover performs primary filtration on the water flowing into the pump casing, and at the same time, the front cover can further protect the internal impeller, impeller cover and other structures.

[0046] A fifth aspect of the present invention provides an air supply device, comprising a water tank, a wet curtain and the water pump of the present invention, wherein the water pump is arranged in the water tank, and the water pump is used to transport water in the water tank to the wet curtain.

[0047] Beneficial effect: Since the air supply device of the present invention includes the water pump of the present invention, the air supply device of the present invention has the same technical effect as the water pump, which will not be repeated here.

[0048] In some embodiments, the air supply device is an evaporative cooling fan.

[0049] When the evaporative cooling fan is running, the water flow of the water pump remains stable, so that the water delivered to the wet curtain remains constant, and the humidity of the wet curtain is kept in a stable range, ensuring the stability of the evaporative cooling effect of the evaporative cooling fan and avoiding large temperature fluctuations. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0051] Figure 1 A flow chart showing the main steps of a control method according to an embodiment of the present invention is shown;

[0052] Figure 2 One of the partial step flow charts of the control method according to one embodiment of the present invention is shown;

[0053] Figure 3 A second flowchart showing some steps of a control method according to an embodiment of the present invention;

[0054] Figure 4 A schematic diagram showing the structure of a control device according to an embodiment of the present invention is shown;

[0055] Figure 5 A schematic diagram of a three-dimensional disassembled structure of a water pump according to an embodiment of the present invention is shown;

[0056] Figure 6 A schematic structural diagram of an air supply device according to an embodiment of the present invention is shown.

[0057] Description of reference numerals:

[0058] 100. Water pump;

[0059] 1. Pump housing; 11. Water inlet; 12. Water outlet; 2. Impeller assembly; 21. Impeller; 22. Axle; 23. Magnet; 24. Front bearing; 25. Rear bearing; 26. Bearing sleeve; 27. Blade cover; 3. Speed ​​detection element; 4. Control main board; 5. Stator assembly; 51. Wire rack; 52. Enameled wire; 6. Front cover; 7. Screws; 8. Wire buckle; 9. Hall element; 10. Power cord; 20. Rear cover;

[0060] 200, control device; 201, acquisition module; 202, judgment module; 203, control module; 204, adjustment module; 205, monitoring module;

[0061] 300, water tank; 400, wet curtain. DETAILED DESCRIPTION

[0062] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0063] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by terms such as "top", "side", "inside" and "outside" are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0064] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0065] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0066] In the related technology, the submersible pump is a permanent magnet brushed DC motor. The mechanical characteristics of the permanent magnet brushed DC motor are relatively rigid. The speed and torsion of the submersible pump fluctuate less with the load. The power supply is usually a constant voltage input, and the input voltage will not be adjusted according to the actual situation. That is, when the actual speed of the submersible pump is inconsistent with the rated speed, it will not be adjusted in real time, which leads to the submersible pump being easily blocked when there are impurities or large particles at the water inlet.

[0067] Combine the following Figures 1 to 6 , describing an embodiment of the present invention.

[0068] like Figures 1 to 3 As shown, according to an embodiment of the present invention, on the one hand, a control method is disclosed for controlling a water pump 100, and the control method comprises the following steps:

[0069] Obtain the actual rotation speed r0 of the water pump 100;

[0070] Determine whether the actual speed r0 of the water pump 100 is equal to the rated speed r;

[0071] If not, the PWM real-time duty cycle t of the water pump 100 is controlled to increase or decrease by ΔX to adjust the actual rotation speed r0 of the water pump 100 .

[0072] The control method of the present application, when the actual speed r0 of the water pump 100 is not equal to the rated speed r, controls the PWM real-time duty cycle t of the water pump 100 to increase or decrease △X, so as to adjust the actual speed r0 of the water pump 100, so that the actual speed r0 of the water pump 100 is closer to or equal to the rated speed r, thereby ensuring the stability and consistency of the water flow of the water pump 100, reducing water flow fluctuations, and thus improving the user experience.

[0073] The water pump 100 may be a submersible pump, which is a special type of pumping equipment that uses compressed air as a power source and can pump various corrosive liquids, liquids containing particles, high viscosity, volatile, flammable, and highly toxic liquids. However, this is not limited to this. In other embodiments, the type of the water pump 100 may also be selected as needed.

[0074] In some embodiments, the PWM real-time duty cycle t of the water pump 100 is controlled to increase or decrease ΔX, and ΔX satisfies the following relationship:

[0075] △X=|(r / r0)t-t|

[0076] t0=(r / r0)×t

[0077] Wherein, t0 is the PWM rated duty cycle of the water pump 100 , and ΔX is the absolute value of the difference between the PWM rated duty cycle of the water pump 100 and the PWM real-time duty cycle of the water pump 100 .

[0078] In the above relationship, r0, r, t0 are all known parameters. The above relationship can be used to calculate the PWM real-time duty cycle t, △X, and t of the water pump 100. According to △X, the PWM real-time duty cycle t of the water pump 100 can be quickly adjusted to make the PWM real-time duty cycle t of the water pump 100 equal to the PWM rated duty cycle t0, thereby ensuring that the actual speed r0 of the water pump 100 is equal to the rated speed r, so that the water pump 100 always runs at the rated speed, ensuring the stability of the water flow of the water pump 100, reducing water flow fluctuations, and improving user experience.

[0079] In this embodiment, the rated speed r is equal to 2000 rpm, the actual speed r0 is equal to 1800 rpm, and the corresponding PWM rated duty cycle t0 is equal to 30%. Then r / r0=2000 / 1800=10 / 9, t=t0 / (r / r0)=30% / (10 / 9)=27%, △X=|(r / r0)t-t|=|(10 / 9)×27%-27%|=3%, and the PWM real-time duty cycle t(27%) of the water pump 100 is controlled to increase by 3%, so that the PWM real-time duty cycle t of the water pump 100 and the PWM rated duty cycle t0 are equal, so that the actual speed r0 of the water pump 100 is equal to or close to the rated speed r.

[0080] It can be understood that when the water pump 100 operates normally, the actual speed r0 of the water pump 100 is equal to the rated speed r. When there are more impurities in the water, the actual speed r0 of the water pump 100 is less than the rated speed r due to the increase in load. When a large number of bubbles are generated in the water, or the water level is too low and there is a shortage of water, the actual speed r0 of the water pump 100 is greater than the rated speed r due to the reduction in load. Based on the above-mentioned situation where the actual speed r0 and the rated speed r are not equal, the present application can adjust the actual speed r0 of the water pump 100 by adjusting the PWM real-time duty cycle t of the water pump 100 to make the actual speed r0 equal to the rated speed r, thereby realizing the functions of constant speed and constant flow of the water pump 100, and improving the situation where the water flow of the water pump 100 fluctuates and is unstable due to dirty blockage.

[0081] Specifically, the load of the water pump 100 may be increased due to silt blockage by adding sediment to the water to simulate the situation. When the sediment increases to a certain amount, the actual rotation speed r0 of the water pump 100 is less than the rated rotation speed r, indicating that the water pump 100 is blocked. The actual rotation speed r0 of the water pump 100 may be increased by controlling the PWM real-time duty cycle t of the water pump 100 to increase by △X, thereby improving the load capacity of the water pump 100 and alleviating the blocking of the water pump 100.

[0082] It can be understood that PWM is the abbreviation of Pulse Width Modulation, and the PWM real-time duty cycle t refers to the ratio of the time the high level is maintained in the output PWM waveform to the modulation period of the PWM.

[0083] The actual rotation speed r0 of the water pump 100 is obtained.

[0084] The actual speed r0 of the water pump 100 is equal to the actual speed of the rotor inside the water pump 100. The actual speed of the rotor of the water pump 100 can be obtained by setting a speed detection element 3 such as a photoelectric encoder or a magnetic encoder to obtain the actual speed r0 of the water pump 100.

[0085] It is determined whether the actual rotation speed r0 of the water pump 100 is equal to the rated rotation speed r.

[0086] Whether the actual rotation speed r0 of the water pump 100 is equal to the rated rotation speed r may be determined by comparing the difference between the actual rotation speed r0 of the water pump 100 and the rated rotation speed r with 0.

[0087] Specifically, let r0-r=A, if:

[0088] A>0, it means that the actual speed r0 of the water pump 100 is greater than the rated speed r;

[0089] A<0, it means that the actual speed r0 of the water pump 100 is less than the rated speed r;

[0090] A=0, which means that the actual rotation speed r0 of the water pump 100 is equal to the rated rotation speed r.

[0091] After the step of determining whether the actual speed r0 of the water pump 100 is equal to the rated speed r, the following steps are further included:

[0092] If yes, the water pump 100 is controlled to run at the actual rotation speed r0.

[0093] Only when the actual speed r0 of the water pump 100 is equal to the rated speed r, the control motherboard 4 will control the water pump 100 to run at the actual speed r0, so that the water pump 100 maintains the actual speed r0 and the rated speed r equal to run, ensuring stable water flow.

[0094] Assuming that the force required for the impeller of the water pump 100 to rotate is F1, the corresponding torque is T1, and the average voltage of the power input power signal is U1, the PWM real-time duty cycle of the water pump 100 in this state is t, the rated speed of the water pump 100 is r, and the actual speed of the water pump 100 obtained is r0, the following relationship can be obtained:

[0095] T1=F1 × R (R is the rotation radius)

[0096] T1=Ct × Φ × Ia

[0097] Ia=T1 / (Ct × Φ)

[0098] U1=t × U high (high level voltage)

[0099] r=U1 / (Ce×Φ)-Ra / (Ce×Φ)×Ia

[0100] From the above formula, we can get r = (U1×Ct×Φ-Ra×T1) / (Ce×Φ / 2×Ct)

[0101] In summary, once the model of the water pump 100 and its motor model are determined, Ce (motor back electromotive force constant), Ct (motor torque constant), Ra (motor internal resistance), Ia (motor current), and Φ (motor flux) are constant, and the rated speed r is proportional to the PWM real-time duty cycle t. The rated speed r can be adjusted by adjusting the PWM real-time duty cycle t. The relationship between the PWM real-time duty cycle t of the water pump 100 and the PWM rated duty cycle t0 can be simplified to a linear relationship, that is, t0=K×t, K=r / r0. However, it can be seen from the above that the relationship is a simplified relationship and has a certain error. Therefore, although the above-mentioned adjustment of the PWM real-time duty cycle t of the water pump 100 according to the △X value can achieve rapid adjustment, there is a certain error, and the PWM real-time duty cycle t and the PWM rated duty cycle t0 will not be equal.

[0102] In view of the above defects, in some embodiments, after the step of controlling the PWM real-time duty cycle t of the water pump 100 to increase or decrease by ΔX, the following steps are further included:

[0103] Determine whether the actual speed r0 of the water pump 100 after adjustment is equal to the rated speed r;

[0104] If not, the PWM real-time duty cycle t of the water pump 100 is controlled to increase or decrease by X, and the actual speed r0 of the water pump 100 is monitored until the actual speed r0 of the water pump 100 is equal to the rated speed r.

[0105] The above steps can eliminate the error after the initial adjustment, avoid the situation where the actual speed r0 of the water pump 100 is still not equal to the rated speed r after adjustment, and ensure the accuracy of the adjustment. Specifically, when it is determined that the actual speed r0 of the water pump 100 after adjustment is not equal to the rated speed r, the PWM real-time duty cycle t of the water pump 100 is further controlled to increase or decrease by X, and the actual speed r0 of the water pump 100 is monitored until the actual speed r0 of the water pump 100 is equal to the rated speed r, thereby ensuring that the water pump 100 always runs at the rated speed r.

[0106] In this embodiment, the PWM real-time duty cycle t of the water pump 100 is first roughly adjusted, that is, the PWM real-time duty cycle t of the water pump 100 is reversely calculated using the rated speed r and the actual speed r0 of the water pump 100, and then the absolute value △X of the difference between the PWM real-time duty cycle t of the water pump 100 and the PWM rated duty cycle t0 of the water pump 100 is obtained. △X can be used to adjust the PWM real-time duty cycle t of the water pump 100 and the PWM rated duty cycle t0 of the water pump 100 to be equal or close in one step, and then fine adjustment is performed. High-precision adjustment is performed according to the error value between the actual speed r0 and the rated speed r of the water pump 100 after adjustment. The PWM real-time duty cycle t of the water pump 100 is controlled to increase or decrease by X each time until the actual speed r0 of the water pump 100 is equal to the rated speed r, thereby taking into account both adjustment efficiency and reliability.

[0107] In some embodiments, the actual speed r0 of the water pump 100 is monitored until the actual speed r0 of the water pump 100 is equal to the rated speed r, including:

[0108] Determine whether the actual speed r0 of the water pump 100 after adjustment is equal to the rated speed r;

[0109] If not, the PWM real-time duty cycle t of the water pump 100 is controlled to continue to increase or decrease by X, and the actual speed r0 after adjustment is determined to be equal to the rated speed r, and this cycle is repeated until the actual speed r0 of the water pump 100 is equal to the rated speed r.

[0110] When it is determined that the actual speed r0 of the water pump 100 after adjustment is not equal to the rated speed r, the PWM real-time duty cycle t of the water pump 100 is controlled to continue to increase or decrease by X, and it is continued to be determined whether the actual speed r0 after adjustment is equal to the rated speed r, and this cycle is repeated until the actual speed r0 of the water pump 100 is equal to the rated speed r. By adjusting the PWM real-time duty cycle t of the water pump 100 by an amplitude of X each time, when the actual speed r0 of the water pump 100 after adjustment is not equal to the rated speed r, the PWM real-time duty cycle t of the water pump 100 is returned to continue to increase or decrease by X until the actual speed r0 of the water pump 100 is equal to the rated speed r, so as to realize multiple small-amplitude adjustments and judgments on the actual speed r0 of the water pump, and avoid the situation where the actual speed r0 and the rated speed r are difficult to match due to a single adjustment amplitude that is too large.

[0111] It is determined whether the actual rotation speed r0 of the water pump 100 after adjustment is equal to the rated rotation speed r.

[0112] Whether the actual speed r0 of the adjusted water pump 100 is equal to the rated speed r can be determined by comparing the difference between the actual speed r0 of the adjusted water pump 100 and the rated speed r with 0. Specifically, if the difference between the actual speed r0 of the adjusted water pump 100 and the rated speed r is greater than 0, it means that the actual speed r0 of the adjusted water pump 100 is greater than the rated speed r; if the difference between the actual speed r0 of the adjusted water pump 100 and the rated speed r is less than 0, it means that the actual speed r0 of the adjusted water pump 100 is less than the rated speed r; if the difference between the actual speed r0 of the adjusted water pump 100 and the rated speed r is equal to 0, it means that the actual speed r0 of the adjusted water pump 100 is equal to the rated speed r.

[0113] In some embodiments, if not, adjusting the PWM real-time duty cycle t of the water pump 100 to increase or decrease by X includes:

[0114] Based on the fact that the actual speed r0 is less than the rated speed r, the PWM real-time duty cycle t of the water pump 100 is controlled to increase by X, so as to increase the actual speed r0 of the water pump 100;

[0115] Based on the fact that the actual speed r0 is greater than the rated speed r, the PWM real-time duty cycle t of the water pump 100 is controlled to decrease by X, so as to reduce the actual speed r0 of the water pump 100 .

[0116] Through the above steps, when the actual speed r0 of the water pump 100 is less than or greater than the rated speed r, the PWM real-time duty cycle t of the water pump 100 can be increased or decreased to increase or decrease the actual speed r0 of the water pump 100 to keep it equal to the rated speed r, thereby ensuring the water flow stability of the water pump 100.

[0117] In some embodiments, 0<X≤20%, and the value of X increased or decreased each time is equal.

[0118] X is limited to 0-20%, so that the PWM real-time duty cycle t of the water pump 100 increases or decreases by 0-20% each time, and the X value increased or decreased each time is equal, that is, the adjustment amplitude is equal, so that the actual speed r0 of the water pump 100 increases or decreases proportionally within a certain range, ensuring the adjustment accuracy.

[0119] In some embodiments, X is 1%.

[0120] Beneficial effect: X is set to 1%, so that the adjustment range is at a smaller level, so that the actual speed r0 of the water pump 100 has more value points, which is easier to match with the rated speed r of the water pump 100, and the adjustment accuracy is improved.

[0121] Of course, in other alternative implementations, X can be set as needed. For example, X can also be set to 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, etc., which is not limited to this embodiment.

[0122] In this embodiment, X is 1% for exemplary description. For example, after the PWM real-time duty cycle t(27%) controlling the water pump 100 is increased by 3% for initial adjustment, if the actual speed r0=1990 rpm of the water pump 100 is less than the rated speed r=2000 rpm, the PWM real-time duty cycle t(27%) is controlled to increase by 1% to t=27%+1%=28%, and the actual speed r0 of the water pump 100 will increase accordingly, and it is judged whether the actual speed r0 is equal to the rated speed r=2000 rpm. If r0≠r, the PWM real-time duty cycle t(28%) is controlled to increase by another 1% to t=28%+1%=29%, and then it is judged whether the actual speed r0 is equal to the rated speed r=2000 rpm. The cycle is repeated in sequence until it is judged that the actual speed r0 of the water pump 100 is equal to the rated speed r=2000 rpm, and the cycle is exited.

[0123] On the contrary, when the actual speed r0 of the water pump 100 is greater than the rated speed r, the PWM duty cycle t is controlled to decrease by 1% to t-1%, and it is judged whether the actual speed r0 is equal to the rated speed r. If r0≠r, the PWM duty cycle t is controlled to decrease by another 1% to t-1%-1%, and then it is judged whether the actual speed r0 is equal to the rated speed r. The cycle is repeated until it is judged that r0=r, and the cycle is exited.

[0124] Further, if not, in the step of increasing or decreasing the PWM duty cycle t of the water pump 100 by adjusting the voltage U input to the water pump 100, the PWM duty cycle t of the water pump 100 is adjusted, thereby adjusting the actual speed r0 of the water pump 100, and the adjustment is convenient. For example, increasing the voltage U input to the water pump 100 can increase the PWM duty cycle t, and conversely, decreasing the voltage U input to the water pump 100 can reduce the PWM duty cycle t.

[0125] Preferably, the voltage U is the average voltage input to the water pump 100 .

[0126] like Figure 4As shown, according to an embodiment of the present invention, on the other hand, a control device is also disclosed. The control device 200 is used to implement the control method of the present invention. The control device 200 includes an acquisition module 201, a judgment module 202 and an adjustment module 204, wherein the acquisition module 201 is used to acquire the actual speed r0 of the water pump, the judgment module 202 is used to judge whether the actual speed r0 of the water pump is equal to the rated speed r, and the adjustment module 204 is used to adjust the PWM real-time duty cycle t of the water pump to increase or decrease △X.

[0127] Since the control device 200 of the present invention is used to implement the control method of the present invention, the control device 200 of the present invention has the same technical effect as the control method, which will not be described in detail herein.

[0128] According to an embodiment of the present invention, on another aspect, a readable storage medium is disclosed. The readable storage medium stores computer instructions. When the computer instructions are executed, the control method of the present invention is executed.

[0129] Since the control method of the present invention is executed when the computer instructions stored in the readable storage medium of the present invention are executed, the readable storage medium of the present invention has the same technical effect as the control method, which will not be described in detail here.

[0130] Exemplarily, the readable storage medium may be a storage CD, a USB flash drive, a hard disk, a magnetic disk, etc., but is not limited thereto. Any readable storage medium that meets the above conditions is within the scope of protection defined in this application.

[0131] like Figure 5 As shown, according to an embodiment of the present invention, on the other hand, a water pump is also disclosed. The water pump 100 is controlled by the control method of the present invention. The water pump 100 includes a pump casing 1, an impeller assembly 2, a speed detection element 3 and a control mainboard 4, wherein the pump casing 1 has a water inlet 11 and a water outlet 12, the impeller assembly 2 is arranged inside the pump casing 1, and the impeller assembly 2 is located between the water inlet 11 and the water outlet 12. The speed detection element 3 is used to detect the actual speed of the impeller assembly 2. The control mainboard 4 is electrically connected to the speed detection element 3, and the control mainboard 4 can control the PWM real-time duty cycle of the water pump 100 to increase or decrease X to adjust the actual speed of the water pump 100.

[0132] When the water pump 100 of the present application is working, water flows into the water pump 100 from the water inlet 11, and is transported to the water outlet 12 and discharged from the water pump 100 through the rotation of the impeller assembly 2. When the speed detection element 3 detects that the actual speed of the impeller assembly 2 is not equal to the rated speed, the control motherboard 4 increases or decreases △X by adjusting the PWM real-time duty cycle of the water pump 100, so as to adjust the actual speed of the impeller assembly 2 to be equal to the rated speed, thereby ensuring that the water pump 100 always runs at the rated speed, realizing the functions of constant speed and constant flow of the water pump 100, and improving the situation where the water flow of the water pump 100 fluctuates due to dirty blockage.

[0133] It should be noted that the actual rotation speed of the impeller assembly 2 is equal to the actual rotation speed of the water pump 100 .

[0134] It can be understood that when the water pump 100 operates normally, the actual speed of the impeller assembly 2 (the actual speed of the water pump 100) is equal to the rated speed. When there are more impurities in the water, the actual speed of the impeller assembly 2 is less than the rated speed due to the increase in load. When a large number of bubbles are generated in the water, or the water level is too low and there is a lack of water, the actual speed of the impeller assembly 2 is greater than the rated speed due to the reduction in load. Based on the above-mentioned situation where the actual speed and the rated speed are not equal, the present application can adjust the actual speed of the impeller assembly 2 to make the actual speed equal to the rated speed, thereby realizing the functions of constant speed and constant flow of the water pump 100, and improving the situation of water flow fluctuation and instability caused by dirty and blocked water in the water pump 100.

[0135] like Figure 5 As shown, in some embodiments, the water inlet 11 is located on the side of the pump casing 1, the water outlet 12 is located on the top of the pump casing 1, the speed detection element 3 is arranged inside the pump casing 1, and the speed detection element 3 is located on the side of the impeller assembly 2 away from the water inlet 11.

[0136] With the above arrangement, water enters the water pump 100 from the water inlet 11 on the side, and is driven by the impeller assembly 2 to flow to the water outlet 12 on the top, so that the water can be transported to the top of the water pump 100. The speed detection element 3 is arranged on the side of the impeller assembly 2 away from the water inlet 11, which can reduce the space occupied on the side of the water inlet 11.

[0137] In some embodiments, the impeller assembly 2 includes an impeller 21 and an axle 22, wherein the impeller 21 has an axial hole, the axle 22 is installed in the axial hole, the axle 22 and the impeller 21 can rotate synchronously to transport water flowing into the water inlet 11 to the water outlet 12, and the speed detection element 3 is used to detect the actual speed of the axle 22.

[0138] When the wheel shaft 22 rotates, it drives the impeller 21 to rotate synchronously. The impeller 21 rotates and beats the water to flow toward the water outlet 12. Since the wheel shaft 22 and the impeller 21 rotate synchronously, the speed detection element 3 detects that the actual speed of the wheel shaft 22 is equal to the actual speed of the impeller assembly 2.

[0139] like Figure 5 As shown, the impeller assembly 2 also includes a magnet 23, a front bearing 24, a rear bearing 25, a bearing sleeve 26 and a blade cover 27, wherein the wheel shaft 22 is embedded in the middle of the magnet 23 to form the core of the rotor, the front bearing 24 and the rear bearing 25 are respectively sleeved on the front and rear of the wheel shaft 22, the bearing sleeve 26 is sleeved on the rear bearing 25, and the blade cover 27 is fixedly connected to the pump housing 1 and arranged corresponding to the water inlet 11 to protect the internal impeller 21 and other components. Water flows into the submersible pump 100 from the blade cover 27 at the water inlet 11, and the wheel shaft 22 rotates while driving the impeller 21 to pump water, and the impeller 21 rotates at a high speed and flows out from the water outlet 12.

[0140] It is understandable that the impeller cover 27 has a water outlet for facilitating water flow, and the impeller cover 27 has the function of filtering large particles of impurities. Impurities with a particle size larger than the water outlet are blocked outside the water pump 100, thereby alleviating the dirtiness and blockage of the impeller 21.

[0141] Specifically, the vane cover 27 can be fixedly connected to the pump housing 1 by screws 7, which is convenient for disassembly and assembly. Specifically, the circumference of the ballast cover can be connected and fixed to the pump housing 1 by multiple screws 7.

[0142] In some embodiments, the impeller assembly 2 also includes a front cover 6, which is fixedly connected to the pump casing 1. The front cover 6 is covered on the impeller compartment cover 27. The front cover 6 can perform initial filtration on the water flowing into the pump casing 1. At the same time, the front cover 6 can further protect the internal impeller compartment cover 27, impeller 21 and other structures.

[0143] In some embodiments, the rotation speed detection element 3 is a photoelectric encoder.

[0144] Setting the speed detection element 3 as a photoelectric encoder can achieve fine control, and the photoelectric encoder has a simple structure and is easy to maintain.

[0145] The photoelectric encoder is a rotation position detector based on photoelectric detection technology, which can convert mechanical motion into digital or analog signals. The working principle of the photoelectric encoder is to detect the gap on the fixed encoder code disk, judge the position of the rotor by photoelectric detection, and output the motion state of the rotor. Since the principle of using the photoelectric encoder to detect the actual speed of the impeller assembly 2 is a prior art, it will not be repeated in this embodiment.

[0146] Of course, in an alternative implementation, the rotation speed detection element 3 may also be a magnetic encoder, and the actual rotation speed of the impeller assembly 2 may also be detected by using the magnetic encoder.

[0147] In some embodiments, the water pump 100 further includes a stator assembly 5 , which is disposed inside the pump housing 1 , and is electrically connected to the control main board 4 , and is used to drive the impeller assembly 2 to rotate.

[0148] The stator assembly 5 is configured to drive the impeller assembly 2 to rotate when powered on, thereby driving water to flow from the water inlet 11 to the water outlet 12 .

[0149] In some embodiments, the stator assembly 5 includes a wire rack 51 and an enameled wire 52, wherein the wire rack 51 is fixed inside the pump housing 1, a stator sheet is arranged on the wire rack 51, the enameled wire 52 is wound on the stator sheet, and the enameled wire 52 is electrically connected to the control main board 4.

[0150] In this embodiment, two stator sheets are arranged on the wire rack 51, and two enameled wires 52 are arranged and are wound one by one on the two stator sheets.

[0151] In some embodiments, the water pump 100 also includes a Hall element 9, which is welded on the control main board 4 and is used to detect the specific rotation position of the impeller assembly 2. This signal will be transmitted to the IC chip on the control main board 4 through the power line 10.

[0152] Furthermore, a wire buckle 8 may be provided, the wire buckle 8 is connected to the pump housing 1 , a wire hole is provided on the wire buckle 8 , and the power cord 10 extends to the outside of the water pump 100 through the wire buckle 8 .

[0153] In some embodiments, the water pump 100 further includes a rear cover 20, which is fixedly connected to the pump housing 1 and covers the control main board 4. The rear cover 20 can protect internal structures such as the stator assembly 5 and the control main board 4.

[0154] Specifically speaking, the rear cover 20 and the pump housing 1 can be fixed by snap connection, which is convenient for disassembly and assembly.

[0155] like Figure 6 As shown, according to an embodiment of the present invention, on the other hand, an air supply device is disclosed, including a water tank 300, a wet curtain 400 and a water pump 100 of the present invention, wherein the water pump 100 is arranged in the water tank 300, and the water pump 100 is used to transport the water in the water tank 300 to the wet curtain 400.

[0156] Since the air supply device of the present invention includes the water pump 100 of the present invention, the air supply device of the present invention has the same technical effect as the water pump 100.

[0157] Exemplarily, the air supply device can be an evaporative cooling fan, and the water pump 100 is directly immersed in the bottom of the water tank 300, and the water level is required to completely cover the surface of the water pump 100. The water inside the water tank 300 is pumped to the top of the wet curtain 400 and poured down by the water pump 100. The wind passes through the wet curtain 400 and uses the principle of heat absorption by evaporation of water to achieve a cooling effect. Since the water flow rate of the water pump 100 remains stable, the humidity of the wet curtain 400 is maintained in a stable range, ensuring the stability of the evaporative cooling effect of the evaporative cooling fan and avoiding large temperature fluctuations.

[0158] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the present application.

Claims

1. A control method for controlling a water pump (100), characterized in that: The control method comprises the following steps: Obtaining the actual rotation speed r0 of the water pump (100); Determining whether the actual rotation speed r0 of the water pump (100) is equal to the rated rotation speed r; If not, the PWM real-time duty cycle t of the water pump (100) is controlled to increase or decrease by ΔX, so as to adjust the actual rotation speed r0 of the water pump (100).

2. The control method according to claim 1, characterized in that: The PWM real-time duty cycle t for controlling the water pump (100) increases or decreases by ΔX, and ΔX satisfies the following relationship: △X=|(r / r0)t-t| t0=(r / r0)×t Wherein, t0 is the PWM rated duty cycle of the water pump (100), and ΔX is the absolute value of the difference between the PWM rated duty cycle of the water pump (100) and the PWM real-time duty cycle of the water pump (100).

3. The control method according to claim 2, characterized in that: After the step of controlling the PWM real-time duty cycle t of the water pump (100) to increase or decrease by ΔX, the step further includes: Determining whether the actual rotation speed r0 of the water pump (100) after adjustment is equal to the rated rotation speed r; If not, the PWM real-time duty cycle t of the water pump (100) is controlled to increase or decrease by X, and the actual rotation speed r0 of the water pump (100) is monitored until the actual rotation speed r0 of the water pump (100) is equal to the rated rotation speed r.

4. The control method according to claim 3, characterized in that: The method of monitoring the actual rotation speed r0 of the water pump (100) until the actual rotation speed r0 of the water pump (100) is equal to the rated rotation speed r comprises: Determining whether the actual rotation speed r0 of the water pump (100) is equal to the rated rotation speed r; If not, the PWM real-time duty cycle t of the water pump (100) is controlled to continue to increase or decrease by X, and it is continued to be determined whether the adjusted actual speed r0 is equal to the rated speed r, and this cycle is repeated until the actual speed r0 of the water pump (100) is equal to the rated speed r.

5. The control method according to claim 3, characterized in that: If not, controlling the PWM real-time duty cycle t of the water pump (100) to increase or decrease by X comprises: Based on the actual rotation speed r0 being less than the rated rotation speed r, controlling the PWM real-time duty cycle t of the water pump (100) to increase by X, so as to increase the actual rotation speed r0 of the water pump (100); Based on the fact that the actual speed r0 is greater than the rated speed r, the PWM real-time duty cycle t of the water pump (100) is controlled to decrease by X, so as to reduce the actual speed r0 of the water pump (100).

6. The control method according to any one of claims 3 to 5, characterized in that: 0<X≤20%, and the X value increased or decreased each time is equal.

7. The control method according to claim 6, characterized in that: X is 1%.

8. The control method according to any one of claims 1 to 5, characterized in that: In the step of controlling the PWM real-time duty cycle t of the water pump (100) to increase or decrease by ΔX if not, the PWM real-time duty cycle t of the water pump (100) is adjusted by adjusting the voltage U input to the water pump (100).

9. A control device, characterized in that: The control device (200) is used to implement the control method according to any one of claims 1 to 8, and the control device (200) comprises: An acquisition module (201), used for acquiring an actual rotation speed r0 of a water pump (100); A judgment module (202) is used to judge whether the actual rotation speed r0 of the water pump (100) is equal to the rated rotation speed r; The regulating module (204) is used to regulate the PWM real-time duty cycle t of the water pump (100) to increase or decrease ΔX.

10. A readable storage medium, characterized in that: The readable storage medium stores computer instructions, and when the computer instructions are executed, the control method according to any one of claims 1 to 8 is executed.

11. A water pump, characterized in that: The water pump (100) is controlled by the control method according to any one of claims 1 to 8, and the water pump (100) comprises: A pump housing (1) having a water inlet (11) and a water outlet (12); An impeller assembly (2) is arranged inside the pump casing (1), and the impeller assembly (2) is located between the water inlet (11) and the water outlet (12); A rotation speed detection element (3) for detecting the actual rotation speed of the impeller assembly (2); A control mainboard (4) is electrically connected to the rotation speed detection element (3), and the control mainboard (4) is capable of controlling the PWM real-time duty cycle of the water pump (100) to increase or decrease by ΔX, so as to adjust the actual rotation speed of the water pump (100).

12. The water pump according to claim 11, characterized in that The rotation speed detection element (3) is a photoelectric encoder.

13. The water pump according to claim 11, characterized in that The impeller assembly (2) comprises: A wheel shaft (22) rotatably disposed in the pump housing (1); An impeller (21) is fixedly sleeved on the wheel shaft (22); A blade compartment cover (27) is arranged at the water inlet (11) of the pump housing (1), and the blade compartment cover (27) has a water outlet.

14. The water pump according to claim 13, characterized in that The water pump (100) further comprises a front cover (6), wherein the front cover (6) is fixedly connected to the pump casing (1), the front cover (6) is arranged to cover the blade compartment cover (27), and the front cover (6) can perform primary filtration on water flowing into the pump casing (1).

15. An air supply device, characterized in that: include: Water tank (300); Wet curtain (400); The water pump (100) according to any one of claims 11 to 14, wherein the water pump (100) is arranged in the water tank (300), and the water pump (100) is used to transport the water in the water tank (300) to the wet curtain (400).

16. The air supply device according to claim 15, characterized in that: The air supply device is an evaporative cooling fan.

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