Control method and device of electronic expansion valve, air source water heater and storage medium

Abstract

The present application provides a control method, device, air source water heater and storage medium for an electronic expansion valve, which is applied to the field of heat pumps, and includes: after the air source water heater is defrosted, obtaining a water temperature control parameter of the air source water heater, determining a first opening of the electronic expansion valve of the air source water heater corresponding to the water temperature control parameter, and obtaining a thermal condition parameter of the air source water heater, determining an opening adjustment parameter of the electronic expansion valve based on the thermal condition parameter, determining a second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, and adjusting the opening of the electronic expansion valve according to the second opening. The method determines the opening of the electronic expansion valve after the air source water heater is defrosted by jointly determining the opening of the electronic expansion valve through the water temperature control parameter and the thermal condition parameter, thereby achieving accurate control of the flow rate of the refrigerant in the air source water heater, improving the smoothness of the flow of the refrigerant in the air source water heater, and avoiding oil blockage in the air source water heater.

Description

Technical Field

[0001] The present application relates to the field of heat pumps, and more specifically, to a control method and device for an electronic expansion valve, an air source water heater and a storage medium in the field of heat pumps. Background Art

[0002] Air source water heaters (air source heat pump water heaters) are a new type of green energy industry. Compared with traditional gas and electric water heaters, they are safer, energy-saving and environmentally friendly. When using an air source water heater in a low-temperature environment, the condenser temperature is lower than the dew point temperature of the outdoor environment, causing the water vapor in the air to condense into water on the condenser surface, and then form frost at low temperatures. In order for the air source water heater to operate normally, the air source water heater needs to be defrosted.

[0003] When defrosting is completed, the low-temperature refrigerant and lubricating oil will flow into the indoor heat exchanger through the throttling device during the defrosting process. At this time, the oil viscosity is relatively large, and at high water temperature, the high and low pressure difference of the system is small. Oil blockage is likely to occur when the electronic expansion valve is not opened properly. Summary of the invention

[0004] The present application provides a control method and device for an electronic expansion valve, an air source water heater and a storage medium. The method determines the opening of the electronic expansion valve after the air source water heater is defrosted by jointly determining water temperature control parameters and thermal condition parameters, thereby achieving accurate control of the flow rate of the refrigerant in the air source water heater, maintaining the smoothness of the flow of the refrigerant in the air source water heater, and avoiding oil blockage in the air source water heater.

[0005] In a first aspect, a control method for an electronic expansion valve is provided, the method comprising: obtaining a water temperature control parameter of the air source water heater after defrosting of the air source water heater is completed; determining a first opening of the electronic expansion valve of the air source water heater corresponding to the water temperature control parameter, and obtaining a thermal condition parameter of the air source water heater; determining an opening adjustment parameter of the electronic expansion valve based on the thermal condition parameter; determining a second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, and adjusting the opening of the electronic expansion valve according to the second opening.

[0006] By adopting the above scheme, after the air source water heater completes defrosting, the first opening of the electronic expansion valve of the air source water heater is preliminarily determined based on the acquired water temperature control parameters, and the opening adjustment parameters of the electronic expansion valve are determined according to the thermal condition parameters of the air source water heater. Then, the second opening of the electronic expansion valve is determined based on the first opening and the opening adjustment parameters, and the opening of the electronic expansion valve is adjusted according to the second opening. The opening of the electronic expansion valve after the air source water heater completes defrosting is jointly determined by the water temperature control parameters and the thermal condition parameters, thereby achieving accurate control of the flow of the refrigerant in the air source water heater, thereby maintaining the smoothness of the flow of the refrigerant in the air source water heater, avoiding the separation of the refrigerant and the lubricating oil, and causing oil blockage in the air source water heater.

[0007] In combination with the first aspect, in some possible implementations, the thermal condition parameters include return air temperature, target return air superheat, refrigerant temperature, target oil blockage temperature, and target set temperature, and the opening adjustment parameters of the electronic expansion valve are determined based on the thermal condition parameters, including: determining the superheat control parameter and the superheat correction parameter based on the return air temperature, the refrigerant temperature and the target return air superheat; determining the difference between the refrigerant temperature and the target oil blockage temperature as the oil blockage control parameter; determining the oil blockage correction parameter based on the refrigerant temperature, the target oil blockage temperature, and the target set temperature; determining the opening adjustment parameter of the electronic expansion valve based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter and the oil blockage correction parameter.

[0008] By adopting the above scheme, the opening adjustment parameters of the electronic expansion valve are determined by the return air temperature, target return air temperature, refrigerant temperature, target oil blockage temperature and target set temperature. Since the first opening is adjusted in real time by the thermal condition parameters of the air source water heater, the opening of the electronic expansion valve can be accurately adjusted in time according to the operating conditions of the air source water heater.

[0009] In combination with the first aspect, in some possible implementations, the opening adjustment parameter of the electronic expansion valve is determined based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter and the oil blockage correction parameter, including: determining a first product of the superheat control parameter and the superheat correction parameter; determining a second product of the oil blockage control parameter and the oil blockage correction parameter; and determining the sum of the first product and the second product as the opening adjustment parameter of the electronic expansion valve.

[0010] By adopting the above scheme, the opening adjustment parameter is determined by the first product obtained by the superheat control parameter and the superheat correction parameter, and the second product of the oil blockage control parameter and the oil blockage correction parameter, thereby strengthening the association between the superheat control parameter and the superheat correction parameter and between the oil blockage control parameter and the oil blockage correction parameter, reducing the performance fluctuation caused by improper parameter setting, avoiding the phenomenon that the electronic expansion valve of the air source water heater is too large, resulting in a slow establishment of superheat of the air source water heater system, and achieving more precise control of the superheat of the air source water heater and avoiding the oil blockage problem.

[0011] In combination with the first aspect, in some possible implementations, superheat control parameters and superheat correction parameters are determined based on the return air temperature, the refrigerant temperature and the target return air superheat, including: determining the difference between the return air temperature and the refrigerant temperature as the return air superheat; determining the difference between the return air superheat and the target return air superheat as the superheat control parameter; determining the superheat correction parameter based on the return air superheat and the target return air superheat.

[0012] By adopting the above scheme, the return air superheat is determined by the difference between the return air temperature and the refrigerant temperature, and then the superheat control parameter and the superheat correction parameter are determined, thereby achieving accurate determination of the superheat control parameter and the superheat correction parameter.

[0013] In combination with the first aspect, in some possible implementations, determining the second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter includes: rounding up the difference between the first opening and the opening adjustment parameter to obtain the second opening of the electronic expansion valve.

[0014] By adopting the above scheme, the second opening degree that the electronic expansion valve needs to adjust is determined by rounding up, which can ensure that the opening degree of the electronic expansion valve will not be lower than the necessary threshold, thereby avoiding the problem of insufficient refrigerant due to too small an opening, which affects the flow of refrigerant.

[0015] In combination with the first aspect, in some possible implementations, determining a first opening of an electronic expansion valve of an air source water heater corresponding to a water temperature control parameter includes: determining the interval between the current moment and the moment when the air source water heater completes defrosting; determining the first opening of the electronic expansion valve corresponding to the interval duration and the water temperature control parameter in a relationship mapping table based on the interval duration and the water temperature control parameter, the relationship mapping table being used to characterize the correspondence between the interval duration, the water temperature control parameter and the first opening.

[0016] By adopting the above scheme, the first opening of the electronic expansion valve corresponding to the water temperature control parameters at different interval lengths is determined through a relationship mapping table. Since the first opening of the electronic expansion valve is determined according to different interval lengths and water temperature control parameters, it is possible to accurately obtain the first opening of the electronic expansion valve according to the operating parameters of the air source water heater.

[0017] In combination with the first aspect, in some possible implementations, after determining the interval between the current moment and the moment when the air source water heater completes defrosting, it also includes: if the interval is within the first duration threshold, controlling the opening of the electronic expansion valve to a third opening.

[0018] By adopting the above scheme, when the interval between the current moment and the moment when the air source water heater completes defrosting is at the first time threshold, the opening of the electronic expansion valve is controlled to be the third opening, ensuring that when the interval is at the first time interval, the refrigerant flow of the air source water heater is sufficient to maintain stable operation of the system and avoid oil blockage in the air source water heater.

[0019] In a second aspect, a control device for an electronic expansion valve is provided, the device comprising: an acquisition unit, for acquiring a water temperature control parameter of an air source water heater after defrosting of the air source water heater is completed; a first determination unit, for determining a first opening of the electronic expansion valve of the air source water heater corresponding to the water temperature control parameter, and acquiring a thermal condition parameter of the air source water heater; a second determination unit, for determining an opening adjustment parameter of the electronic expansion valve based on the thermal condition parameter; an adjustment unit, for determining a second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, and adjusting the opening of the electronic expansion valve according to the second opening.

[0020] In a third aspect, an air source water heater is provided, characterized in that the water heater comprises: a memory for storing executable program code; a processor for calling and running the executable program code from the memory, so that the water heater executes the method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0021] In a fourth aspect, a computer program product is provided, comprising: a computer program code, which, when executed on a computer, enables the computer to execute the method in the first aspect or any possible implementation of the first aspect.

[0022] In a fifth aspect, a computer-readable storage medium is provided, which stores a computer program code. When the computer program code runs on a computer, the computer executes the method in the above-mentioned first aspect or any possible implementation manner of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of an air source water heater provided in an embodiment of the present application;

[0024] Figure 2 It is a flow chart of a control method of an electronic expansion valve provided in an embodiment of the present application;

[0025] Figure 3It is a flow chart of a control method of an electronic expansion valve provided in an embodiment of the present application;

[0026] Figure 4 It is a flow chart of a control method of an electronic expansion valve provided in an embodiment of the present application;

[0027] Figure 5 It is a scenario schematic diagram of a control method of an electronic expansion valve provided in an embodiment of the present application;

[0028] Figure 6 It is a flow chart of a control method of an electronic expansion valve provided in an embodiment of the present application;

[0029] Figure 7 is a structural schematic diagram of a control device for an electronic expansion valve provided in an embodiment of the present application;

[0030] Figure 8 is a structural schematic diagram of a control device for an electronic expansion valve provided in an embodiment of the present application;

[0031] Fig. 9 It is a structural schematic diagram of an air source water heater provided in an embodiment of the present application.

[0032] Reference numerals:

[0033] DETAILED DESCRIPTION

[0034] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0035] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0036] Figure 1 It is a structural schematic diagram of an air source water heater provided in an embodiment of the present application.

[0037] When the amount of flammable refrigerant charged is small for safety reasons, the system pressure of the air source water heater is small, the viscosity of the lubricating oil increases, and it is easy to accumulate at the electronic expansion valve to form oil blockage. And after the defrost mode ends, the air source water heater returns to the heating mode, but the low-temperature refrigerant and lubricating oil may still remain in the system. At this time, if high water temperature and low pressure difference coexist, the lubricating oil may accumulate at the throttling device again, causing oil blockage.

[0038] Based on this, a control method of an electronic expansion valve is proposed in the embodiment of the present application, which is applied to an air source water heater. The main structure of the air source water heater is as follows: Figure 1 shown.

[0039] The air source water heater comprises a compressor 1, a four-way valve 2, an indoor heat exchanger 3, an outdoor heat exchanger 7, a first filter 4, a second filter 6, and an electronic expansion valve 5. A refrigerant temperature sensor 11 is installed in the outdoor heat exchanger 7, which collects the refrigerant temperature on the evaporation side of the outdoor heat exchanger 7 outside the non-subcooling flow path.

[0040] Optionally, the air source water heater also includes a pressure sensor 9, which is installed between the refrigerant outlet of the outdoor heat exchanger 7 and the four-way valve 2 to obtain the pressure value of the refrigerant flowing from the outdoor heat exchanger 7 to the four-way valve 2, and then obtain the saturated evaporation temperature of the refrigerant based on the pressure value. The saturated evaporation temperature of the refrigerant is determined by the actual detected pressure value of the refrigerant, and the saturated evaporation temperature of the refrigerant can be accurately obtained.

[0041] Optionally, the air source water heater further includes an outdoor temperature sensor, which is installed on the outdoor heat exchanger 7 to obtain the outdoor ambient temperature of the air source water heater. In the embodiment of the present application, the outdoor ambient temperature of the air source water heater is directly obtained by the outdoor temperature sensor, so that the outdoor ambient temperature of the air source water heater can be accurately obtained.

[0042] Optionally, the air source water heater also includes a return air temperature sensor 10 installed at the air intake of the compressor 1, which collects the return air temperature of the refrigerant at the air intake of the compressor. In the embodiment of the present application, the return air temperature is one of the thermal condition parameters of the air source water heater.

[0043] Optionally, the air source water heater further comprises a water outlet temperature sensor 8 installed at the water outlet of the indoor heat exchanger 3 , which collects the water outlet temperature at the water outlet of the indoor heat exchanger 3 .

[0044] By installing the above components, after the air source water heater completes defrosting, it obtains the water temperature control parameters of the air source water heater (including the outdoor ambient temperature and the water outlet temperature), preliminarily determines the first opening of the electronic expansion valve of the air source water heater based on the water temperature control parameters, and determines the opening adjustment parameters of the electronic expansion valve according to the thermal condition parameters of the air source water heater, and then determines the second opening of the electronic expansion valve based on the first opening and the opening adjustment parameters, adjusts the opening of the electronic expansion valve according to the second opening, and jointly determines the opening of the electronic expansion valve after the air source water heater completes defrosting through the water temperature control parameters and the thermal condition parameters, thereby achieving accurate control of the flow of the refrigerant in the air source water heater, thereby maintaining the smoothness of the flow of the refrigerant in the air source water heater, avoiding the separation of the refrigerant and the lubricating oil, and causing oil blockage in the air source water heater.

[0045] based on Figure 1 The structural diagram shown below will be combined with Figure 2-Figure 9 , the control method of the electronic expansion valve provided in the embodiment of the present application is introduced in detail.

[0046] See also Figure 2 , is a flow chart of a method for controlling an electronic expansion valve provided in an embodiment of the present application. Figure 2 As shown, the method of the embodiment of the present application may include the following steps S101-S104.

[0047] S101, after the air source water heater is defrosted, obtaining water temperature control parameters of the air source water heater;

[0048] In one embodiment, when the air source water heater is defrosted, the pressure in the system will change, which may cause the flow of lubricating oil in the system to change as well, or even accumulate in certain parts, causing oil blockage. Therefore, in the embodiment of the present application, after the air source water heater is defrosted, it is necessary to adjust the opening of the electronic expansion valve to control the flow of the refrigerant in the air source water heater and maintain the smooth flow of the refrigerant in the air source water heater.

[0049] The water temperature control parameter refers to the parameter that affects the heat exchange between the refrigerant and water in the air source water heater, which is any one of the outdoor ambient temperature and the water outlet temperature at the water outlet of the indoor heat exchanger 3, or a combination of the two.

[0050] S102, determining a first opening degree of an electronic expansion valve of the air source water heater corresponding to a water temperature control parameter, and obtaining a thermal condition parameter of the air source water heater;

[0051] In one embodiment, after the water temperature control parameter is obtained, a first opening of the electronic expansion valve corresponding to the water temperature control parameter is determined, wherein the first opening refers to the opening of the electronic expansion valve preliminarily determined according to the water temperature control parameter.

[0052] In one embodiment, when the water temperature control parameter includes the outlet water temperature and the outdoor ambient temperature, the first initial opening of the electronic expansion valve corresponding to the water temperature control parameter is first determined, and then the second initial opening of the electronic expansion valve corresponding to the outdoor ambient temperature is determined, and then the first opening of the electronic expansion valve corresponding to the water temperature control parameter is determined to be the average of the first initial opening and the second initial opening. It can be understood that in the embodiment of the present application, the first initial opening corresponding to the outlet water temperature and the second initial opening corresponding to the outdoor ambient temperature can be established in advance through experimental data.

[0053] In another embodiment, a mapping relationship between water temperature control parameters (including water outlet temperature and outdoor ambient temperature) and the first opening degree can be established. Thus, after obtaining the water outlet temperature and the outdoor ambient temperature, the water temperature control parameters can be obtained according to the water outlet temperature and the outdoor ambient temperature, and then the first opening degree corresponding to the water temperature control parameters can be obtained. By way of example, the first opening degree corresponding to the water temperature control parameters can be 205.

[0054] The air source water heater obtains the thermal condition parameters of the air source water heater while obtaining the first opening of the electronic expansion valve, wherein the thermal condition parameters refer to the parameters that affect the flow of the refrigerant in the air source water heater.

[0055] S103, determining an opening adjustment parameter of the electronic expansion valve based on the thermal condition parameter;

[0056] In one embodiment, after obtaining the thermal condition parameters, the opening adjustment parameters of the electronic expansion valve that currently need to be adjusted are determined based on the thermal condition parameters of the air source water heater, wherein the opening adjustment parameters refer to the opening that needs to be further adjusted based on the first opening of the electronic expansion valve.

[0057] The thermal condition parameters include return air superheat and target return air superheat. For example, if the difference between the return air superheat and the target return air superheat is 15°C, and the coefficient between the difference between the return air superheat and the target return air superheat and the opening adjustment parameter is 0.3, then the opening adjustment parameter is determined to be 5.

[0058] S104, determining a second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, and adjusting the opening of the electronic expansion valve according to the second opening.

[0059] In one embodiment, after the first opening degree and the opening degree adjustment parameter are determined, the second opening degree of the electronic expansion valve is determined according to the first opening degree and the opening degree adjustment parameter. Exemplarily, the second opening degree may be 210.

[0060] In an embodiment of the present application, after the air source water heater completes defrosting, the first opening of the electronic expansion valve of the air source water heater is preliminarily determined based on the acquired water temperature control parameters, and the opening adjustment parameters of the electronic expansion valve are determined according to the thermal condition parameters of the air source water heater. Then, the second opening of the electronic expansion valve is determined based on the first opening and the opening adjustment parameters, and the opening of the electronic expansion valve is adjusted according to the second opening. The opening of the electronic expansion valve after the air source water heater completes defrosting is jointly determined by the water temperature control parameters and the thermal condition parameters, thereby achieving accurate control of the flow rate of the refrigerant in the air source water heater, thereby maintaining the smoothness of the flow of the refrigerant in the air source water heater, avoiding the separation of the refrigerant and the lubricating oil, and causing oil blockage in the air source water heater.

[0061] See also Figure 3 , is a flow chart of a method for controlling an electronic expansion valve provided in an embodiment of the present application. Figure 3 As shown, the method of the embodiment of the present application may include the following steps S201-S204.

[0062] S201, determining a superheat control parameter and a superheat correction parameter based on the return air temperature, the refrigerant temperature and the target return air superheat;

[0063] In one embodiment, the thermal condition parameters include return air temperature, target return air superheat, refrigerant temperature, target oil blockage temperature, and target set temperature, wherein the return air temperature refers to the temperature of the refrigerant after leaving the outdoor heat exchanger and before being sucked into the compressor, the refrigerant temperature refers to the temperature of the refrigerant when it leaves the outdoor heat exchanger, the target return air superheat refers to the difference between the preset return air temperature and the saturated evaporation temperature of the refrigerant, the target oil blockage temperature refers to the temperature set to prevent the air source water heater from being blocked, and the target set temperature refers to the refrigerant temperature set when exiting defrost.

[0064] In one embodiment, in this embodiment, the return air superheat (Tesh) of the refrigerant flowing into the compressor can be obtained by the difference between the return air temperature and the refrigerant temperature. Then, the superheat control parameter is calculated by the difference between the return air superheat and the target return air superheat (Esh); and the superheat correction parameter X is obtained by substituting the return air superheat and the target return air superheat into the superheat correction function.

[0065] In one embodiment, this embodiment can also calculate the refrigerant saturated evaporation temperature of the refrigerant through the pressure value obtained by the pressure sensor 9 installed between the refrigerant outlet of the outdoor heat exchanger 7 and the four-way valve 2, and calculate the difference between the return air temperature and the refrigerant saturated evaporation temperature to obtain the return air superheat, and then calculate the superheat control parameter according to the difference between the return air superheat and the target return air superheat; the superheat correction parameter obtained subsequently is similar to the above-mentioned embodiment and will not be repeated here.

[0066] Return air superheat (Tesh=) return air temperature - refrigerant temperature (saturated evaporation temperature);

[0067] Superheat control parameter (A) = return air superheat (Tesh) - target return air superheat (Esh);

[0068] Superheat correction parameter (X) = f1(Tesh, Esh).

[0069] S202, determining the difference between the refrigerant temperature and the target oil blockage temperature as an oil blockage control parameter;

[0070] S203, determining an oil blockage correction parameter based on the refrigerant temperature, the target oil blockage temperature, and the target set temperature;

[0071] In one embodiment, the oil blockage control parameter is determined as the difference between the refrigerant temperature (T1) and the target oil blockage temperature (T2). After the oil blockage control parameter is obtained, the oil blockage correction parameter is further determined according to the oil blockage control parameter (B), the target oil blockage temperature and the target set temperature. Specifically, the oil blockage correction parameter (Y) is obtained by substituting the refrigerant temperature, the target oil blockage temperature and the target set temperature (T3) into the oil blockage correction function.

[0072] Oil blockage control parameter (B) = refrigerant temperature (T1) - target oil blockage temperature (T2);

[0073] Oil blockage correction parameter (Y) = f2 (T1, T2, T3).

[0074] S204: determining an opening adjustment parameter of the electronic expansion valve based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter, and the oil blockage correction parameter.

[0075] Further, in an embodiment of the present application, after determining the superheat control parameter, the superheat correction parameter, the oil blockage control parameter and the oil blockage correction parameter, the first product of the superheat control parameter and the superheat correction parameter, and the second product of the oil blockage control parameter and the oil blockage correction parameter are determined, and the sum of the first product and the second product is determined as the opening adjustment parameter of the electronic expansion valve.

[0076] Opening adjustment parameter (C) = A*X+B*Y.

[0077] Furthermore, after the opening adjustment parameter is obtained, the difference between the first opening and the opening adjustment parameter is rounded up to obtain the second opening of the electronic expansion valve.

[0078] The second opening = RoundUp (the first opening - the opening adjustment parameter (C), 0).

[0079] Exemplarily, if the first opening is 350 and the opening adjustment parameter is 14.6, then the second opening is determined to be 336.

[0080] In the embodiment of the present application, the opening adjustment parameter of the electronic expansion valve is determined by the return air temperature, the target return air temperature, the refrigerant temperature, the target oil blockage temperature and the target set temperature. Since the first opening is adjusted in real time by the thermal condition parameter of the air source water heater, the opening of the electronic expansion valve can be accurately adjusted in time according to the operating conditions of the air source water heater; and the opening adjustment parameter is determined by the first product obtained by the superheat control parameter and the superheat correction parameter, and the second product of the oil blockage control parameter and the oil blockage correction parameter, thereby strengthening the association between the superheat control parameter and the superheat correction parameter and the oil blockage control parameter and the oil blockage correction parameter, thereby reducing the risk of accidents caused by improper parameter settings. The performance fluctuations caused by this can be avoided, and the electronic expansion valve of the air source water heater can be avoided from being opened too wide, which leads to a slower superheat temperature establishment, thereby achieving more accurate control of the superheat of the air source water heater and avoiding oil blockage problems; and the return air superheat is determined by the difference between the return air temperature and the refrigerant temperature, and then the superheat control parameters and the superheat correction parameters are determined, thereby achieving accurate determination of the superheat control parameters and the superheat correction parameters; and the second opening that the electronic expansion valve needs to be adjusted is determined by rounding up, which can ensure that the opening of the electronic expansion valve will not be lower than the necessary threshold, thereby avoiding the problem of insufficient refrigerant due to too small an opening, which affects the flow of refrigerant.

[0081] See also Figure 4 , is a flow chart of a method for controlling an electronic expansion valve provided in an embodiment of the present application. Figure 4 As shown, the method of the embodiment of the present application may include the following steps S301-S305.

[0082] S301, after the air source water heater is defrosted, obtaining water temperature control parameters of the air source water heater;

[0083] In one embodiment, when the air source water heater is defrosted, the pressure in the system will change, which may cause the flow of lubricating oil in the system to change as well, or even accumulate in certain parts, causing oil blockage. Therefore, in the embodiment of the present application, after the air source water heater is defrosted, it is necessary to adjust the opening of the electronic expansion valve to control the flow of the refrigerant in the air source water heater and maintain the smooth flow of the refrigerant in the air source water heater.

[0084] Optionally, the air source water heater can obtain water temperature control parameters through sensors.

[0085] S302, determining the interval between the current time and the time when the air source water heater completes defrosting;

[0086] S303, based on the interval time and the water temperature control parameter, determining in a relationship mapping table a first opening of the electronic expansion valve corresponding to the interval time and the water temperature control parameter, the relationship mapping table being used to characterize the corresponding relationship between the interval time, the water temperature control parameter and the first opening, and obtaining the thermal condition parameter of the air source water heater;

[0087] In one embodiment, after the air source water heater completes defrosting, it starts a timer to count the interval between the current time and the time when defrosting is completed, and then determines the first opening of the corresponding electronic expansion valve in the relationship mapping table based on the interval time and water temperature control parameters.

[0088] Optionally, see Figure 5 In the embodiment of the present application, the water temperature control parameter is illustrated by taking the outdoor ambient temperature as an example. In the embodiment of the present application, the relationship mapping table is as follows: Figure 5 As shown, it includes a first mapping curve and a second mapping curve. If the interval duration is at the second duration threshold, the first opening is determined in the first mapping curve corresponding to the second duration threshold based on the outdoor ambient temperature; if the interval duration is at the third duration threshold, the first opening is determined in the second mapping curve corresponding to the third duration threshold based on the outdoor ambient temperature. Exemplarily, the second duration threshold is (60, 90], and the third duration threshold may be (90, 120]. If the interval duration is at the second duration threshold and the outdoor ambient temperature is -10°C, the first opening is determined to be 300; if the interval duration is at the third duration threshold and the outdoor ambient temperature is -10°C, the first opening is determined to be 200. Optionally, the opening adjustment parameter may also be a positive value or a negative value.

[0089] Further, in the embodiment of the present application, if it is determined that the interval between the current moment and the moment when the air source water heater completes defrosting is at the first time threshold, the opening of the electronic expansion valve is controlled to be the third opening. Exemplarily, the first time threshold may be (0, 60], and the third opening is 480.

[0090] Further, in an embodiment of the present application, if it is determined that the interval between the current moment and the moment when the air source water heater completes defrosting is greater than the third time threshold, the opening of the electronic expansion valve can be freely adjusted. For example, the current opening of the electronic expansion valve can be maintained.

[0091] S304, determining an opening adjustment parameter of the electronic expansion valve based on the thermal condition parameter;

[0092] S305, determining a second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, and adjusting the opening of the electronic expansion valve according to the second opening.

[0093] Optionally, in an embodiment of the present application, the second opening of the electronic expansion valve is obtained based on the first opening and the opening adjustment parameter.

[0094] It can be understood that in the embodiment of the present application, after the opening adjustment parameter of the electronic expansion valve is determined by the thermal condition parameter, the second opening of the electronic expansion valve is further determined based on the opening adjustment parameter and the first opening, and then the opening of the electronic expansion valve is increased according to the second opening.

[0095] Exemplarily, in an embodiment of the present application, when the air source water heater is in defrost mode, the opening of the electronic expansion valve is 200, and the opening adjustment parameter is -30. Since the opening adjustment parameter is a negative value, the second opening is determined to be 230, and the opening of the electronic expansion valve is increased according to the second opening.

[0096] In an embodiment of the present application, the first opening of the electronic expansion valve corresponding to the water temperature control parameters at different interval durations is determined through a relationship mapping table. Since the first opening of the electronic expansion valve is determined according to different interval durations and the water temperature control parameters, it is possible to accurately obtain the first opening of the electronic expansion valve according to the operating parameters of the air source water heater; and when the interval duration between the current moment and the moment when the air source water heater completes defrosting is at a first duration threshold, the opening of the electronic expansion valve is controlled to be a third opening, ensuring that when the interval duration is at the first duration interval, the refrigerant flow of the air source water heater meets the requirements for maintaining stable operation of the system to avoid oil blockage in the air source water heater.

[0097] The following will be combined Figure 6 The control of the electronic expansion valve provided in the embodiment of the present application is described in detail with a specific example.

[0098] S1, obtain water temperature control parameters; S2, determine the interval time between the current moment and the moment when the air source water heater completes defrosting; S3, if the interval time is within the first time threshold, determine the opening of the electronic expansion valve to be the third opening; S4, if the interval time is within the second time threshold, determine the first opening of the electronic expansion valve according to the first mapping curve corresponding to the second time threshold; S5, if the interval time is within the third time threshold, determine the first opening of the electronic expansion valve according to the second mapping curve corresponding to the third time threshold; S6, determine the opening adjustment parameter of the electronic expansion valve based on the thermal condition parameter; S7, determine the second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, and adjust the opening of the electronic expansion valve according to the second opening.

[0099] In an embodiment of the present application, after the air source water heater completes defrosting, the first opening of the electronic expansion valve of the air source water heater is preliminarily determined based on the acquired water temperature control parameters, and the opening adjustment parameters of the electronic expansion valve are determined according to the thermal condition parameters of the air source water heater. Then, the second opening of the electronic expansion valve is determined based on the first opening and the opening adjustment parameters, and the opening of the electronic expansion valve is adjusted according to the second opening. The opening of the electronic expansion valve after the air source water heater completes defrosting is jointly determined by the water temperature control parameters and the thermal condition parameters, thereby achieving accurate control of the flow rate of the refrigerant in the air source water heater, thereby maintaining the smoothness of the flow of the refrigerant in the air source water heater, avoiding the separation of the refrigerant and the lubricating oil, and causing oil blockage in the air source water heater.

[0100] based on Figure 1 The structural diagram of Figure 7-Figure 8 , the control device of the electronic expansion valve provided in the embodiment of the present application is introduced in detail. It should be noted that, Figure 7-Figure 8 The electronic expansion valve control device is used to implement the present application Figure 2-Figure 6 For the convenience of explanation, only the part related to the embodiment of the present application is shown. For the specific technical details not disclosed, please refer to the present application. Figure 2-Figure 6 The embodiment shown.

[0101] like Figure 7 As shown, the control device of the electronic expansion valve includes: an acquisition unit, a first determination unit, a second determination unit and an adjustment unit.

[0102] An acquisition unit 11 is used to acquire a water temperature control parameter of the air source water heater after defrosting of the air source water heater is completed;

[0103] A first determination unit 12 is used to determine a first opening degree of an electronic expansion valve of the air source water heater corresponding to a water temperature control parameter, and obtain a thermal condition parameter of the air source water heater;

[0104] A second determination unit 13, configured to determine an opening adjustment parameter of the electronic expansion valve based on a thermal condition parameter;

[0105] The adjustment unit 14 is used to determine the second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, and adjust the opening of the electronic expansion valve according to the second opening.

[0106] Optionally, the second determining unit 13 includes:

[0107] A first determination subunit 131 is used to determine a superheat control parameter and a superheat correction parameter based on the return air temperature, the refrigerant temperature and the target return air superheat;

[0108] The second determining subunit 132 determines the difference between the refrigerant temperature and the target oil blockage temperature as an oil blockage control parameter;

[0109] The third determination subunit 133 determines the oil blockage correction parameter based on the refrigerant temperature, the target oil blockage temperature, and the target set temperature;

[0110] The fourth determining subunit 134 determines an opening adjustment parameter of the electronic expansion valve based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter and the oil blockage correction parameter.

[0111] Optionally, the fourth determining subunit 134 is specifically configured to:

[0112] determining a first product of a superheat control parameter and a superheat correction parameter;

[0113] Determine a second product of the oil blockage control parameter and the oil blockage correction parameter;

[0114] The sum of the first product and the second product is determined as the opening adjustment parameter of the electronic expansion valve.

[0115] Optionally, the first determining subunit 131 is specifically configured to:

[0116] Determine the difference between the return air temperature and the refrigerant temperature as the return air superheat;

[0117] Determine the difference between the return air superheat and the target return air superheat as the superheat control parameter;

[0118] A superheat correction parameter is determined based on the return air superheat and the target return air superheat.

[0119] Optionally, the adjusting unit 14 includes: an adjusting subunit 141 .

[0120] The adjusting subunit 141 is used to round up the difference between the first opening and the opening adjustment parameter to obtain the second opening of the electronic expansion valve.

[0121] Optionally, the first determining unit 12 includes: a fifth determining subunit 121 and a sixth determining subunit 122 .

[0122] The fifth determining subunit 121 is used to determine the interval between the current moment and the moment when the air source water heater completes defrosting;

[0123] The sixth determination subunit 122 is used to determine the first opening of the electronic expansion valve corresponding to the interval duration and the water temperature control parameter in the relationship mapping table based on the interval duration and the water temperature control parameter. The relationship mapping table is used to characterize the correspondence between the interval duration, the water temperature control parameter and the first opening.

[0124] Optionally, see Figure 8The control device of the electronic expansion valve also includes: a control unit 15.

[0125] The control unit 15 is configured to control the opening degree of the electronic expansion valve to be a third opening degree if the interval duration is within the first duration threshold.

[0126] In an embodiment of the present application, after the air source water heater completes defrosting, the first opening of the electronic expansion valve of the air source water heater is preliminarily determined based on the acquired water temperature control parameters, and the opening adjustment parameters of the electronic expansion valve are determined according to the thermal condition parameters of the air source water heater. Then, the second opening of the electronic expansion valve is determined based on the first opening and the opening adjustment parameters, and the opening of the electronic expansion valve is adjusted according to the second opening. The opening of the electronic expansion valve after the air source water heater completes defrosting is jointly determined by the water temperature control parameters and the thermal condition parameters, thereby achieving accurate control of the flow rate of the refrigerant in the air source water heater, thereby maintaining the smoothness of the flow of the refrigerant in the air source water heater, avoiding the separation of the refrigerant and the lubricating oil, and causing oil blockage in the air source water heater.

[0127] See also Fig. 9 , is a schematic diagram of the structure of an air source water heater provided in an embodiment of the present application. Fig. 9 As shown, the air source water heater 500 includes a processor 501 and a memory 502. The processor 501 is electrically connected to the memory 502.

[0128] The processor 501 is the control center of the air source water heater 500 and may include one or more processing cores. The processor 501 uses various interfaces and lines to connect various parts of the entire air source water heater 500, and executes various functions and processes data of the air source water heater 500 by running or calling computer programs stored in the memory 502, and calling data stored in the memory 502, so as to control the air source water heater 500 as a whole. Optionally, the processor 501 can be implemented in at least one hardware form of digital signal processing (DSP), field programmable gate array (FPGA), and programmable logic array (PLA). The processor 501 can integrate one or a combination of CPU, graphics processing unit (GPU), modem, etc. Among them, the CPU mainly processes the operating system, user pages, and applications; the GPU is responsible for rendering and drawing display content; and the modem is used to process wireless communications. It can be understood that the above-mentioned modem may not be integrated into the processor 501, but may be implemented separately through a communication chip.

[0129] The memory 502 can be used to store software programs and modules, and the processor 501 executes various functional applications and data processing by running the computer programs and modules stored in the memory 502. The memory 502 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, a computer program required for at least one function, etc.; the data storage area can store data created according to the use of the air source water heater 500, etc.

[0130] In addition, the memory 502 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage device. Accordingly, the memory 502 may also include a memory controller to provide the processor 501 with access to the memory 502.

[0131] In this embodiment, the processor 501 in the air source water heater 500 will load the instructions corresponding to the processes of one or more computer programs into the memory 502 according to the following steps, and the processor 501 will run the computer program stored in the memory 502 to implement various functions, as follows:

[0132] After the air source water heater is defrosted, the water temperature control parameters of the air source water heater are obtained;

[0133] Determine a first opening degree of an electronic expansion valve of the air source water heater corresponding to a water temperature control parameter, and obtain a thermal condition parameter of the air source water heater;

[0134] Determining an opening adjustment parameter of the electronic expansion valve based on the thermal condition parameter;

[0135] A second opening degree of the electronic expansion valve is determined based on the first opening degree and the opening degree adjustment parameter, and the opening degree of the electronic expansion valve is adjusted according to the second opening degree.

[0136] Optionally, the thermal condition parameters include return air temperature, target return air superheat, refrigerant temperature, target oil blockage temperature, and target set temperature. When the processor 501 determines the opening adjustment parameters of the electronic expansion valve based on the thermal condition parameters, it specifically executes:

[0137] Determine a superheat control parameter and a superheat correction parameter based on the return air temperature, the refrigerant temperature and the target return air superheat;

[0138] Determine the difference between the refrigerant temperature and the target oil blockage temperature as the oil blockage control parameter;

[0139] Determine the oil blockage correction parameter based on the refrigerant temperature, the target oil blockage temperature, and the target set temperature;

[0140] The opening adjustment parameter of the electronic expansion valve is determined based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter and the oil blockage correction parameter.

[0141] Optionally, when the processor 501 determines the opening adjustment parameter of the electronic expansion valve based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter, and the oil blockage correction parameter, the processor 501 specifically performs:

[0142] determining a first product of a superheat control parameter and a superheat correction parameter;

[0143] Determine a second product of the oil blockage control parameter and the oil blockage correction parameter;

[0144] The sum of the first product and the second product is determined as the opening adjustment parameter of the electronic expansion valve.

[0145] Optionally, when the processor 501 determines the superheat control parameter and the superheat correction parameter based on the return air temperature, the refrigerant temperature and the target return air superheat, the processor 501 specifically performs:

[0146] Determine the difference between the return air temperature and the refrigerant temperature as the return air superheat;

[0147] Determine the difference between the return air superheat and the target return air superheat as the superheat control parameter;

[0148] Determine the superheat correction parameter based on the return air superheat and the target return air superheat. Optionally, when the processor 501 determines the second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, specifically executes:

[0149] The difference between the first opening degree and the opening degree adjustment parameter is rounded up to obtain the second opening degree of the electronic expansion valve.

[0150] Optionally, when the processor 501 determines the first opening of the electronic expansion valve of the air source water heater corresponding to the water temperature control parameter, the processor 501 specifically performs:

[0151] Determine the interval between the current time and the time when the air source water heater completes defrosting;

[0152] Based on the interval time and the water temperature control parameter, the first opening of the electronic expansion valve corresponding to the interval time and the water temperature control parameter is determined in the relationship mapping table, and the relationship mapping table is used to characterize the correspondence between the interval time, the water temperature control parameter and the first opening.

[0153] Optionally, after determining the interval between the current moment and the moment when the air source water heater completes defrosting, the processor 501 may further execute:

[0154] If the interval duration is within the first duration threshold, the opening degree of the electronic expansion valve is controlled to be a third opening degree.

[0155] It should be understood that the device provided in the embodiment of the present application is used to execute the above-mentioned control method of an electronic expansion valve, and thus can achieve the same effect as the above-mentioned implementation method.

[0156] In the case of an integrated unit, the device may include a processing module and a storage module. When the device is applied to an air source water heater, the processing module may be used to control and manage the actions of the air source water heater. The storage module may be used to support the air source water heater to execute related program codes, etc.

[0157] The processing module may be a processor or a controller, which may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of this application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module may be a memory.

[0158] In addition, the device provided in the embodiment of the present application can specifically be a chip, a component or a module, and the chip may include a connected processor and a memory; wherein the memory is used to store instructions, and when the processor calls and executes the instructions, the chip can execute a control method for an electronic expansion valve provided in the above embodiment.

[0159] An embodiment of the present application also provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is executed on a computer, the computer executes the above-mentioned related method steps to implement a control method for an electronic expansion valve provided in the above embodiment.

[0160] This embodiment further provides a computer program product. When the computer program product is run on a computer, the computer is enabled to execute the above-mentioned related steps to implement a control method for an electronic expansion valve provided in the above embodiment.

[0161] Among them, the device, computer-readable storage medium, computer program product or chip provided in this embodiment is used to execute the corresponding method provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method provided above, and will not be repeated here.

[0162] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0163] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0164] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A control method for an electronic expansion valve, characterized in that: The method comprises: After the air source water heater is defrosted, obtaining water temperature control parameters of the air source water heater; Determine a first opening degree of the electronic expansion valve of the air source water heater corresponding to the water temperature control parameter, and obtain a thermal condition parameter of the air source water heater; determining an opening adjustment parameter of the electronic expansion valve based on the thermal condition parameter; The thermal condition parameters include return air temperature, target return air superheat, refrigerant temperature, target oil blockage temperature, and target set temperature. The target oil blockage temperature refers to the temperature set to prevent the air source water heater from being blocked. The target set temperature refers to the refrigerant temperature set when exiting defrosting. The opening adjustment parameters of the electronic expansion valve are determined based on the thermal condition parameters, including: Determining a superheat control parameter and a superheat correction parameter based on the return air temperature, the refrigerant temperature, and the target return air superheat; Determine the difference between the refrigerant temperature and the target oil blockage temperature as an oil blockage control parameter; determining an oil blockage correction parameter based on the refrigerant temperature, the target oil blockage temperature, and the target set temperature; determining an opening adjustment parameter of the electronic expansion valve based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter, and the oil blockage correction parameter; A second opening of the electronic expansion valve is determined based on the first opening and the opening adjustment parameter, and the opening of the electronic expansion valve is adjusted according to the second opening.

2. The method according to claim 1, characterized in that: The determining of the opening adjustment parameter of the electronic expansion valve based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter and the oil blockage correction parameter comprises: determining a first product of the superheat control parameter and the superheat correction parameter; determining a second product of the oil blockage control parameter and the oil blockage correction parameter; The sum of the first product and the second product is determined as an opening adjustment parameter of the electronic expansion valve.

3. The method according to claim 1, characterized in that: The determining of the superheat control parameter and the superheat correction parameter based on the return air temperature, the refrigerant temperature and the target return air superheat comprises: Determine the difference between the return air temperature and the refrigerant temperature as the return air superheat; Determine the difference between the return air superheat and the target return air superheat as the superheat control parameter; The superheat correction parameter is determined based on the return air superheat and the target return air superheat.

4. The method according to claim 1, characterized in that: The determining the second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter comprises: The difference between the first opening and the opening adjustment parameter is rounded up to obtain a second opening of the electronic expansion valve.

5. The method according to claim 1, characterized in that The determining of a first opening degree of the electronic expansion valve of the air source water heater corresponding to the water temperature control parameter comprises: Determine the interval between the current time and the time when the air source water heater completes defrosting; Based on the interval duration and the water temperature control parameter, the first opening of the electronic expansion valve corresponding to the interval duration and the water temperature control parameter is determined in a relationship mapping table, and the relationship mapping table is used to characterize the correspondence between the interval duration, the water temperature control parameter and the first opening.

6. The method according to claim 5, characterized in that After determining the interval between the current moment and the moment when the air source water heater completes defrosting, the method further includes: If the interval duration is within the first duration threshold, the opening degree of the electronic expansion valve is controlled to be a third opening degree.

7. A control device for an electronic expansion valve, characterized in that: The device comprises: An acquisition unit, configured to acquire a water temperature control parameter of the air source water heater after defrosting of the air source water heater is completed; A first determination unit is used to determine a first opening of the electronic expansion valve of the air source water heater corresponding to the water temperature control parameter, and obtain thermal condition parameters of the air source water heater, wherein the thermal condition parameters include return air temperature, target return air superheat, refrigerant temperature, target oil blockage temperature, and target set temperature. The target oil blockage temperature refers to a temperature set to prevent the air source water heater from being blocked, and the target set temperature refers to a refrigerant temperature set when exiting defrosting; a second determination unit, for determining a superheat control parameter and a superheat correction parameter based on the return air temperature, the refrigerant temperature and the target return air superheat; determining a difference between the refrigerant temperature and the target oil blockage temperature as an oil blockage control parameter; determining an oil blockage correction parameter based on the refrigerant temperature, the target oil blockage temperature and the target set temperature; determining an opening adjustment parameter of the electronic expansion valve based on the superheat control parameter, the superheat correction parameter, the oil blockage control parameter and the oil blockage correction parameter; An adjusting unit is used to determine a second opening of the electronic expansion valve based on the first opening and the opening adjustment parameter, and adjust the opening of the electronic expansion valve according to the second opening.

8. An air source water heater, characterized in that: The water heater comprises: A memory for storing executable program codes; A processor is used to call and run the executable program code from the memory, so that the water heater executes the method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program code, and when the computer program code is executed, the method according to any one of claims 1 to 6 is implemented.

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