Air source heat pump water heater and control method, device and storage medium thereof

Abstract

The present invention provides an air-source heat pump water heater, as well as a control method, device, and storage medium. The control method includes obtaining the outer ring temperature, return water temperature, and real-time high-pressure pressure when entering defrost mode; determining a target high-pressure pressure based on the outer ring temperature and return water temperature; and controlling the compressor frequency based on the target high-pressure pressure and the real-time high-pressure pressure. The present invention addresses the problem that the technical solutions in related arts fail to effectively improve defrost efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning, and in particular to an air source heat pump water heater and a control method, device and storage medium thereof. Background Art

[0002] In the prior art, air-source heat pump water heaters are prone to high-pressure protection during defrosting. Unlike conventional air conditioners, air-source heat pump water heaters use a plate heat exchanger as the evaporating end during defrosting, with high-temperature hot water as the heat source. Improper settings of the compressor frequency, the outdoor unit valve steps, and the conditions for exiting defrost during defrosting can all lead to high-pressure protection during the defrosting process. To address this issue, prior art controls use frequency as the control target during defrosting, correcting the frequency based on the high-pressure pressure. However, prior art controls on compressor frequency are imprecise, often setting a target frequency. When the high-pressure pressure reaches a threshold, the frequency can easily overshoot, leading to large system fluctuations and reduced defrosting efficiency.

[0003] It can be seen that the problem existing in the related art is that the technical solutions in the related art cannot effectively improve the defrosting efficiency. Summary of the Invention

[0004] The problem solved by the present invention is that the technical solutions in the related art cannot effectively improve the defrosting efficiency.

[0005] To solve the above problems, a first object of the present invention is to provide a control method for an air source heat pump water heater.

[0006] A second object of the present invention is to provide a control device for an air source heat pump water heater.

[0007] A third object of the present invention is to provide an air source heat pump water heater.

[0008] A fourth object of the present invention is to provide a readable storage medium.

[0009] To achieve the first objective of the present invention, an embodiment of the present invention provides a control method for an air source heat pump water heater, the control method comprising:

[0010] When entering defrost mode, obtain the outer ring temperature, return water temperature and real-time high pressure;

[0011] Determine the target high pressure according to the outer ring temperature and return water temperature;

[0012] The compressor frequency is controlled according to the target high pressure and the real-time high pressure.

[0013] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: in the solution of this embodiment, fuzzy control is performed according to the target high pressure and the real-time high pressure when the unit is defrosted. Compared with setting the target frequency and then reducing the frequency after the high pressure reaches a certain value, the control method of the present invention is more precise, not easy to overshoot, and effectively improves the stability and efficiency of the defrosting process.

[0014] In one embodiment of the present invention, controlling the compressor frequency according to the target high pressure and the real-time high pressure includes:

[0015] Determine the difference E and the high pressure change rate f based on the target high pressure and the real-time high pressure;

[0016] Determine the compressor frequency adjustment period and period frequency adjustment amount based on the difference E and the high pressure change rate f;

[0017] The compressor performs frequency adjustment every other compressor frequency adjustment period, and the frequency adjustment amount each time is a periodic frequency adjustment amount.

[0018] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: in the process of adjusting the compressor frequency, it is necessary to periodically adjust the compressor frequency, and determine the compressor frequency adjustment period and the periodic frequency adjustment amount according to the difference E and the high pressure change rate f, which can make the compressor frequency adjustment process more accurate and further improve the reliability of the control method of the present invention.

[0019] In one embodiment of the present invention, determining the difference and the high pressure change rate based on the target high pressure and the real-time high pressure includes:

[0020] Subtract the target high pressure from the real high pressure to determine the difference E;

[0021] Get the historical high pressure before the rated time t and calculate the high pressure change rate f.

[0022]

[0023] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: through the solution of this embodiment, the difference E and the high-voltage change rate f can be accurately determined, thereby effectively improving the reliability of the control method of the present invention.

[0024] In one embodiment of the present invention, determining the compressor frequency adjustment period and the periodic frequency adjustment amount according to the difference E and the high pressure change rate f includes:

[0025] According to the difference E, the compressor frequency adjustment period is determined;

[0026] The periodic frequency adjustment amount is determined based on the difference E and the high voltage change rate f.

[0027] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: through the solution of this embodiment, a more accurate compressor frequency adjustment period and period frequency adjustment amount can be determined, thereby improving the stability of the control method of the present invention.

[0028] In one embodiment of the present invention, determining the compressor frequency adjustment period according to the difference E includes:

[0029] When the absolute value of the difference E is greater than the first threshold, the compressor frequency adjustment period is the first period;

[0030] When the absolute value of the difference E is less than the first threshold value and greater than the second threshold value, the compressor frequency adjustment period is the second period;

[0031] When the absolute value of the difference E is less than the second threshold, the compressor frequency remains unchanged;

[0032] The first period is smaller than the second period.

[0033] Compared with the prior art, the technical effect achieved by adopting this technical solution is: through the solution of this embodiment, the compressor frequency adjustment period can be determined more accurately according to actual conditions, thereby effectively improving the reliability of the control method of the present invention.

[0034] In one embodiment of the present invention, determining the periodic frequency adjustment amount according to the difference E and the high voltage change rate f includes:

[0035] According to the difference E, the initial cycle frequency adjustment amount is determined;

[0036] Determine the correction coefficient based on the difference E and the high pressure change rate f;

[0037] The initial period frequency adjustment amount is multiplied by the correction coefficient to determine the period frequency adjustment amount.

[0038] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: in the solution of this embodiment, the initial periodic frequency adjustment amount is first determined based on the difference E, and then the correction coefficient is determined based on the difference E and the high-voltage change rate f, so that a periodic frequency adjustment amount with higher accuracy can be obtained, thereby effectively improving the stability of the control method of the present invention.

[0039] In one embodiment of the present invention, the greater the high-voltage change rate f, the smaller the correction coefficient; and the greater the absolute value of the difference E, the greater the correction coefficient.

[0040] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: according to the difference E and the high voltage change rate f, different correction coefficients are adaptively determined, which can make the periodic frequency adjustment amount more accurate, thereby effectively improving the reliability of the control method of the present invention.

[0041] In one embodiment of the present invention, after controlling the compressor frequency according to the target high pressure and the real-time high pressure, the control method further includes:

[0042] After exiting the defrost mode, obtain the actual defrost time of the defrost;

[0043] According to the actual defrost time and the target high pressure, a new target high pressure is determined at the outer ring temperature and the return water temperature.

[0044] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: taking high pressure as the control target, stabilizing the high pressure pressure within an efficient defrost range, and then correcting the target high pressure pressure of the next defrost at the same outer ring temperature and return water temperature according to the defrost time, which can ensure clean defrosting and accelerate the defrost process.

[0045] In one embodiment of the present invention, determining a new target high pressure at an outer ring temperature and a return water temperature according to the actual defrost time and the target high pressure includes:

[0046] When the actual defrost time is greater than the preset time threshold, a new target high pressure pressure is determined based on the actual defrost time and the target high pressure pressure;

[0047] in,

[0048] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: the control method of this embodiment corrects the target high pressure of the next defrost at the same outer ring temperature and return water temperature according to the defrost time, effectively improving the defrost efficiency.

[0049] In one embodiment of the present invention, the control method further includes:

[0050] After exiting the defrost mode, the compressor frequency drops to the lowest operating frequency, the outdoor fan runs at a high speed, and after the four-way valve is reversed, the unit enters soft start control.

[0051] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: in the solution of this embodiment, turning on the fan can not only take away the condensed water generated by defrosting, but also prevent it from frosting quickly again, and reduce the switching noise, thereby effectively improving the reliability of the control method of the present invention.

[0052] To achieve the second purpose of the present invention, an embodiment of the present invention provides a control device for an air source heat pump water heater, the control device including: a detection module, the detection module is used to obtain the outer ring temperature, return water temperature and real-time high pressure when entering the defrost mode; a calculation module, the calculation module is used to determine the target high pressure according to the outer ring temperature and the return water temperature; a control module, the control module is used to control the compressor frequency according to the target high pressure and the real-time high pressure.

[0053] The control device of the air source heat pump water heater in an embodiment of the present invention implements the steps of the control method of the air source heat pump water heater in any embodiment of the present invention, and thus has all the beneficial effects of the control method of the air source heat pump water heater in any embodiment of the present invention, which will not be repeated here.

[0054] To achieve the third purpose of the present invention, an embodiment of the present invention provides an air source heat pump water heater, which includes: a processor, a memory, and a program or instruction stored in the memory and runnable on the processor. When the program or instruction is executed by the processor, the steps of the control method of the air source heat pump water heater of any embodiment of the present invention are implemented.

[0055] The air source heat pump water heater of an embodiment of the present invention implements the steps of the control method of the air source heat pump water heater of any embodiment of the present invention, and thus has all the beneficial effects of the control method of the air source heat pump water heater of any embodiment of the present invention, which will not be repeated here.

[0056] To achieve the fourth purpose of the present invention, an embodiment of the present invention provides a readable storage medium, which stores a program or instruction. When the program or instruction is executed by a processor, the steps of the control method of the air source heat pump water heater in any embodiment of the present invention are implemented.

[0057] The readable storage medium of an embodiment of the present invention implements the steps of the control method of the air source heat pump water heater of any embodiment of the present invention, and thus has all the beneficial effects of the control method of the air source heat pump water heater of any embodiment of the present invention, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is a flowchart of the steps of a control method for an air source heat pump water heater according to some embodiments of the present invention. DETAILED DESCRIPTION

[0059] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0060] See also Figure 1 This embodiment provides a control method for an air source heat pump water heater, the control method comprising:

[0061] S100: When entering the defrost mode, obtain the outer ring temperature, return water temperature and real-time high pressure;

[0062] S200: Determine the target high pressure according to the outer ring temperature and the return water temperature;

[0063] S300: Controlling the compressor frequency according to the target high pressure and the real-time high pressure.

[0064] In this embodiment, the air source heat pump water heater is prone to high-pressure protection during defrosting. Improper settings of the compressor frequency, external unit valve steps, and defrosting exit conditions during defrosting may all lead to high-pressure protection during the defrosting process. In the prior art, frequency is used as the control target during defrosting, and the frequency is corrected according to the high-pressure pressure. Since the control and adjustment of the compressor frequency is not precise enough, the target frequency is often set. When the high-pressure pressure reaches the threshold, the frequency reduction is prone to overshoot in this case, resulting in large system fluctuations and reduced defrosting efficiency.

[0065] Before S100, the control method also includes judging whether the unit meets the defrost conditions. When it is judged to be yes, the unit enters the defrost mode and executes the control method of S100. It should be noted that the defrost conditions in this embodiment are the same as the common defrost conditions in the prior art, and will not be described in detail here. For example, when it is judged that the unit meets the defrost conditions, the compressor frequency is controlled to drop to the lowest frequency of 20HZ (low frequency operation, reducing the high and low pressure difference of the system and reducing the switching noise). After running for 40s, the four-way valve is controlled to reverse, and the fan is closed 2s in advance. After reversing, the target high pressure pressure is quickly reached.

[0066] Furthermore, in S100, when entering the defrost mode, the outer ring temperature, return water temperature and real-time high pressure are obtained; it should be noted that the outer ring temperature is the external ambient temperature, the return water temperature is the temperature of the water returning from the air source heat pump water heater, and the real-time high pressure is the high pressure measured by the compressor in real time.

[0067] Furthermore, in S200 , a target high-pressure pressure is determined based on the outer ring temperature and the return water temperature. The target high-pressure pressure is the high-pressure pressure that the unit needs to reach. At this target high-pressure pressure, the unit achieves higher defrost efficiency. The higher the outer ring temperature, the higher the target high-pressure pressure; and the higher the return water temperature, the higher the target high-pressure pressure. For example, the relationship between the outer ring temperature, return water temperature, and target high-pressure pressure is shown in Table 1.

[0068] Table 1: Target high pressure reference table

[0069]

[0070] Furthermore, in S300 , the compressor frequency is controlled according to the target high pressure and the real-time high pressure. By controlling the compressor frequency, the real-time high pressure is brought closer to the target high pressure, thereby improving the defrosting efficiency.

[0071] It can be understood that in the scheme of this embodiment, fuzzy control is performed based on the target high pressure and the real-time high pressure when the unit is defrosted. Compared with setting the target frequency and then reducing the frequency after the high pressure reaches a certain value, the control method of the present invention is more precise, not prone to overshoot, and effectively improves the stability and efficiency of the defrosting process.

[0072] Furthermore, in a specific embodiment, controlling the compressor frequency according to the target high pressure and the real-time high pressure includes:

[0073] Determine the difference E and the high pressure change rate f based on the target high pressure and the real-time high pressure;

[0074] Determine the compressor frequency adjustment period and period frequency adjustment amount based on the difference E and the high pressure change rate f;

[0075] The compressor performs frequency adjustment every other compressor frequency adjustment period, and the frequency adjustment amount each time is a periodic frequency adjustment amount.

[0076] It can be understood that in the process of adjusting the compressor frequency, it is necessary to adjust the compressor frequency periodically. Determining the compressor frequency adjustment period and the periodic frequency adjustment amount based on the difference E and the high pressure change rate f can make the compressor frequency adjustment process more accurate and further improve the reliability of the control method of the present invention.

[0077] Furthermore, in a specific embodiment, determining the difference and the high pressure change rate based on the target high pressure and the real-time high pressure includes:

[0078] Subtract the target high pressure from the real high pressure to determine the difference E;

[0079] Get the historical high pressure before the rated time t and calculate the high pressure change rate f.

[0080]

[0081] In this embodiment, the high pressure change rate f is the rate of change of the real-time high pressure. The greater the high pressure change rate f, the greater the change value of the real-time high pressure per unit time.

[0082] It can be understood that, through the solution of this embodiment, the difference E and the high voltage change rate f can be accurately determined, thereby effectively improving the reliability of the control method of the present invention.

[0083] Furthermore, in a specific embodiment, determining the compressor frequency adjustment period and the periodic frequency adjustment amount according to the difference E and the high pressure change rate f includes:

[0084] According to the difference E, the compressor frequency adjustment period is determined;

[0085] The periodic frequency adjustment amount is determined based on the difference E and the high voltage change rate f.

[0086] In this embodiment, the difference E can reflect the difference between the real-time high-pressure pressure and the target high-pressure pressure. When the difference is large, the compressor frequency adjustment cycle can be appropriately reduced to make the real-time high-pressure pressure reach the target high-pressure pressure faster; the high-pressure change rate f can intuitively reflect the rate of change of the high-pressure pressure. According to the difference E and the high-pressure change rate f, the periodic frequency adjustment amount can be determined more accurately.

[0087] It can be understood that, through the solution of this embodiment, a more accurate compressor frequency adjustment period and period frequency adjustment amount can be determined, thereby improving the stability of the control method of the present invention.

[0088] Furthermore, in a specific embodiment, determining the compressor frequency adjustment period according to the difference E includes:

[0089] When the absolute value of the difference E is greater than the first threshold, the compressor frequency adjustment period is the first period;

[0090] When the absolute value of the difference E is less than the first threshold value and greater than the second threshold value, the compressor frequency adjustment period is the second period;

[0091] When the absolute value of the difference E is less than the second threshold, the compressor frequency remains unchanged;

[0092] The first period is smaller than the second period.

[0093] In this embodiment, when the absolute value of the difference E is greater than the first threshold value, it means that the difference is large at this time, so it is necessary to reduce the compressor frequency adjustment cycle so that the high-pressure pressure can reach the target high-pressure pressure faster, so the compressor frequency adjustment cycle is controlled to be the first cycle; when the absolute value of the difference E is less than the first threshold value and greater than the second threshold value, it means that the difference is small at this time, and the real-time high-pressure pressure is already relatively close to the target high-pressure pressure, so the compressor frequency adjustment cycle is the second cycle to avoid frequent adjustment of the compressor frequency to affect the accuracy of the control method; when the absolute value of the difference E is less than the second threshold value, it means that the real-time high-pressure pressure is basically the same as the target high-pressure pressure, and the compressor frequency can be controlled to remain unchanged.

[0094] Preferably, the first threshold value is -5, the second threshold value is 1, the first period value is 2s, and the second period value is 10s.

[0095] It should be noted that in actual application, when the unit enters the defrost mode, the real-time high-pressure pressure is often less than the target high-pressure pressure, that is, the difference E is generally a negative number. Therefore, in actual application, when E is less than 0, the control of the compressor frequency adjustment cycle can be more refined; when the water temperature is high, the real-time high-pressure pressure may be greater than the target high-pressure pressure. This situation rarely occurs, so the control of the compressor frequency adjustment cycle can be simpler at this time.

[0096] For example, when E≤-5, the compressor frequency adjustment cycle is 2s; when -5<E≤-1, the compressor frequency adjustment cycle is 10s; when -1<E≤1, the compressor frequency remains unchanged; when 1<E≤5, the compressor frequency adjustment cycle is 10s; when 5<E, the compressor frequency adjustment cycle is 2s.

[0097] Preferably, when E≤-5, the compressor frequency adjustment cycle is 2s; when -5<E<0, the compressor frequency adjustment cycle is 10s; when 0≤E<1, the compressor frequency remains unchanged; when 1≤E<4, the compressor frequency adjustment cycle is 10s.

[0098] It can be understood that, through the solution of this embodiment, the compressor frequency adjustment period can be determined more accurately according to actual conditions, thereby effectively improving the reliability of the control method of the present invention.

[0099] Furthermore, in a specific embodiment, determining the periodic frequency adjustment amount according to the difference E and the high voltage change rate f includes:

[0100] According to the difference E, the initial cycle frequency adjustment amount is determined;

[0101] Determine the correction coefficient based on the difference E and the high pressure change rate f;

[0102] The initial period frequency adjustment amount is multiplied by the correction coefficient to determine the period frequency adjustment amount.

[0103] In this embodiment, the initial cycle frequency adjustment amount is determined based on the difference E; when the difference is a negative number, it means that the real-time high-pressure pressure is less than the target high-pressure pressure, and the initial cycle frequency adjustment amount is determined to be a, where a is a constant greater than 0; when the difference is in interval b, interval b includes 0, which means that the real-time high-pressure pressure is approximately equal to the target high-pressure pressure, and the compressor frequency position can be controlled to remain unchanged; when the difference is on the right side of interval b, it means that the real-time high-pressure pressure is greater than the target high-pressure pressure. At this time, the initial cycle frequency adjustment amount is determined to be a negative number, and the real-time high-pressure pressure is reduced by reducing the compressor frequency.

[0104] For example, when E≤-5, the initial cycle frequency adjustment amount is 1Hz; when -5<E<0, the initial cycle frequency adjustment amount is 1Hz; when 0≤E<1, the compressor frequency remains unchanged; when 1≤E<4, the initial cycle frequency adjustment amount is -0.1*the current operating frequency of the compressor.

[0105] It can be understood that in the scheme of this embodiment, the initial periodic frequency adjustment amount is first determined based on the difference E, and then the correction coefficient is determined based on the difference E and the high voltage change rate f, so that a periodic frequency adjustment amount with higher accuracy can be obtained, thereby effectively improving the stability of the control method of the present invention.

[0106] Furthermore, in a specific embodiment, the greater the high-voltage change rate f is, the smaller the correction coefficient is; and the greater the absolute value of the difference E is, the greater the correction coefficient is.

[0107] In this embodiment, the larger the high-pressure change rate f, the faster the real-time high-pressure pressure changes. At this time, the correction coefficient can be appropriately reduced to reduce the periodic frequency adjustment amount, thereby avoiding frequency overshoot; the larger the absolute value of the difference E, the larger the difference between the real-time high-pressure pressure and the target high-pressure pressure. At this time, the correction coefficient can be increased to increase the periodic frequency adjustment amount, speed up the speed at which the real-time high-pressure pressure reaches the target high-pressure pressure, and improve the defrosting efficiency.

[0108] For example, see Table 2.

[0109] Table 2: Correction coefficient table

[0110] E≤-5 -5＜E＜0 0≤E＜1 1≤E＜4 f≥0.5 1.2 0.5 0 0.5 0.3＜f＜0.5 1.3 0.6 0 0.6 0.1≤f≤0.3 1.4 0.7 0 0.7 f＜0.1 1.5 0.8 0 0.8

[0111] It can be understood that adaptively determining different correction coefficients according to the difference E and the high voltage change rate f can make the periodic frequency adjustment amount more accurate, thereby effectively improving the reliability of the control method of the present invention.

[0112] Furthermore, in a specific embodiment, after controlling the compressor frequency according to the target high pressure and the real-time high pressure, the control method further includes:

[0113] After exiting the defrost mode, obtain the actual defrost time of the defrost;

[0114] According to the actual defrost time and the target high pressure, a new target high pressure is determined at the outer ring temperature and the return water temperature.

[0115] It should be noted that the actual defrost time is the defrost end time minus the defrost start time.

[0116] It can be understood that taking high pressure as the control target, stabilizing the high pressure pressure within an efficient defrost range, and then correcting the target high pressure pressure of the next defrost at the same outer ring temperature and return water temperature according to the defrost time can ensure clean defrost and speed up the defrost process.

[0117] Furthermore, in a specific embodiment, determining a new target high pressure at the outer ring temperature and the return water temperature according to the actual defrost time and the target high pressure includes:

[0118] When the actual defrost time is greater than the preset time threshold, a new target high pressure pressure is determined based on the actual defrost time and the target high pressure pressure;

[0119] in,

[0120] In this embodiment, when the actual defrost time is greater than the preset time threshold, it indicates that the defrost efficiency is low, and the target high pressure at the current outer ring temperature and return water temperature can be appropriately increased.

[0121] It should be noted that the unit of the actual defrost time is seconds, the unit of the coefficient is bar / min, and the new target high pressure is the target high pressure in the next defrost mode under the current outer ring temperature and return water temperature.

[0122] Preferably, the coefficient is 2 bar / min.

[0123] It can be understood that the control method of this embodiment corrects the target high pressure of the next defrost at the same outer ring temperature and return water temperature according to the defrost time, thereby effectively improving the defrost efficiency.

[0124] Furthermore, in a specific embodiment, the control method further includes:

[0125] After exiting the defrost mode, the compressor frequency drops to the lowest operating frequency, the outdoor fan runs at a high speed, and after the four-way valve is reversed, the unit enters soft start control.

[0126] It can be understood that in the solution of this embodiment, turning on the fan can not only take away the condensed water generated by defrosting, but also prevent it from frosting quickly again, and reduce the switching noise, thereby effectively improving the reliability of the control method of the present invention.

[0127] Furthermore, this embodiment provides a control device for an air source heat pump water heater, which includes: a detection module, which is used to obtain the outer ring temperature, return water temperature and real-time high-pressure pressure when entering the defrost mode; a calculation module, which is used to determine the target high-pressure pressure based on the outer ring temperature and the return water temperature; and a control module, which is used to control the compressor frequency based on the target high-pressure pressure and the real-time high-pressure pressure.

[0128] The control device of the air source heat pump water heater in an embodiment of the present invention implements the steps of the control method of the air source heat pump water heater in any embodiment of the present invention, and thus has all the beneficial effects of the control method of the air source heat pump water heater in any embodiment of the present invention, which will not be repeated here.

[0129] Furthermore, this embodiment provides an air source heat pump water heater, which includes: a processor, a memory, and a program or instruction stored in the memory and executable on the processor. When the program or instruction is executed by the processor, the steps of the control method of the air source heat pump water heater of any embodiment of the present invention are implemented.

[0130] The air source heat pump water heater of an embodiment of the present invention implements the steps of the control method of the air source heat pump water heater of any embodiment of the present invention, and thus has all the beneficial effects of the control method of the air source heat pump water heater of any embodiment of the present invention, which will not be repeated here.

[0131] Furthermore, this embodiment provides a readable storage medium storing a program or instruction. When the program or instruction is executed by a processor, the steps of the control method of the air source heat pump water heater according to any embodiment of the present invention are implemented.

[0132] The readable storage medium of an embodiment of the present invention implements the steps of the control method of the air source heat pump water heater of any embodiment of the present invention, and thus has all the beneficial effects of the control method of the air source heat pump water heater of any embodiment of the present invention, which will not be repeated here.

[0133] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the claims.

Claims

1. A control method for an air source heat pump water heater, characterized in that: The control method includes: When entering defrost mode, obtain the outer ring temperature, return water temperature and real-time high pressure; determining a target high pressure according to the outer ring temperature and the return water temperature; controlling the compressor frequency according to the target high pressure and the real-time high pressure; The controlling the compressor frequency according to the target high-pressure pressure and the real-time high-pressure pressure includes: Determining a difference E and a high pressure change rate f according to the target high pressure and the real-time high pressure; Determining the compressor frequency adjustment period and the periodic frequency adjustment amount according to the difference E and the high pressure change rate f; The compressor performs frequency adjustment every other compressor frequency adjustment period, and the frequency adjustment amount each time is the period frequency adjustment amount.

2. The control method according to claim 1, characterized in that: The determining of the difference and the high pressure change rate according to the target high pressure and the real-time high pressure includes: Subtracting the target high pressure from the real-time high pressure to determine the difference E; Obtain the historical high pressure before the rated time t, calculate the high pressure change rate f, 。 3. The control method according to claim 1, wherein: The step of determining the compressor frequency adjustment period and the periodic frequency adjustment amount according to the difference E and the high pressure change rate f includes: Determining the compressor frequency adjustment period according to the difference E; The periodic frequency adjustment amount is determined according to the difference E and the high voltage change rate f.

4. The control method according to claim 3, characterized in that: Determining the compressor frequency adjustment period according to the difference E includes: When the absolute value of the difference E is greater than a first threshold, the compressor frequency adjustment period is a first period; When the absolute value of the difference E is less than the first threshold value and greater than the second threshold value, the compressor frequency adjustment period is the second period; When the absolute value of the difference E is less than the second threshold, the compressor frequency remains unchanged; The first period is smaller than the second period.

5. The control method according to claim 3, characterized in that: The determining the periodic frequency adjustment amount according to the difference E and the high voltage change rate f includes: Determining the initial period frequency adjustment amount according to the difference E; Determining a correction coefficient according to the difference E and the high pressure change rate f; The initial period frequency adjustment amount is multiplied by the correction coefficient to determine the period frequency adjustment amount.

6. The control method according to claim 5, characterized in that: The larger the high-pressure change rate f is, the smaller the correction coefficient is; the larger the absolute value of the difference E is, the larger the correction coefficient is.

7. The control method according to claim 1, characterized in that: After controlling the compressor frequency according to the target high-pressure pressure and the real-time high-pressure pressure, the control method further includes: After exiting the defrost mode, obtaining the actual defrost time of the defrost; A new target high pressure is determined at the outer ring temperature and the return water temperature according to the actual defrost time and the target high pressure.

8. The control method according to claim 7, characterized in that: According to the actual defrosting time and the target The target high pressure is determined at the outer ring temperature and the return water temperature, including: When the actual defrost time is greater than a preset time threshold, determining the new target high pressure according to the actual defrost time and the target high pressure; in, .

9. The control method according to any one of claims 1 to 8, characterized in that: The control method further includes: After exiting the defrost mode, the compressor frequency drops to the lowest operating frequency, the external fan runs at a high speed, and after the four-way valve is reversed, the unit enters soft start control.

10. A control device for an air source heat pump water heater, characterized in that: The steps of the control method according to any one of claims 1 to 9 can be implemented, and the control device includes: A detection module, wherein the detection module is used to obtain the outer ring temperature, the return water temperature and the real-time high pressure when entering the defrost mode; a calculation module, configured to determine a target high pressure according to the outer ring temperature and the return water temperature; A control module is configured to control a compressor frequency according to the target high-pressure pressure and the real-time high-pressure pressure.

11. An air source heat pump water heater, characterized in that: The air source heat pump water heater includes: a processor, a memory, and a program or instruction stored in the memory and executable on the processor. When the program or instruction is executed by the processor, the steps of the control method according to any one of claims 1 to 9 are implemented.

12. A readable storage medium, characterized in that: The readable storage medium stores a program or instruction, and when the program or instruction is executed by a processor, the steps of the control method according to any one of claims 1 to 9 are implemented.

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