Heat pump water heater control method and device, heat pump water heater and storage medium

Abstract

The invention discloses a heat pump water heater control method and device, a heat pump water heater and a storage medium, and belongs to the technical field of heat pump systems. When the heat pump water heater enters the heat storage mode, whether heat storage energy needs to exist or not is judged according to the temperature of the water tank; when heat storage energy needs to exist, whether hot water heating energy needs to exist or not is determined according to the environment temperature; and when the heating water energy requirement exists, the heating water energy requirement of the heat pump water heater is adjusted according to a first temperature difference value and a second temperature difference value, the first temperature difference value is used for representing the water side inlet and outlet water temperature difference value of the water-fluorine heat exchanger, and the second temperature difference value is used for representing the difference value between the outlet water temperature and the target outlet water temperature. In this way, the water heating energy requirement of the heat pump water heater can be adjusted in real time according to the working state of the water-fluorine heat exchanger and the deviation between the water outlet temperature and the target value, and operation and water heating of the heat pump water heater can be controlled more accurately.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pump systems, and particularly to a control method and device for a heat pump water heater, a heat pump water heater, and a storage medium. Background Art

[0002] Conventional heat pump water heaters generally heat the water in the water tank continuously through a heat pump system, so that the water in the water tank maintains a relatively high water temperature for users to use. During the energy storage process, it is generally achieved by controlling whether the outlet water temperature of the heat pump reaches the heat storage required temperature. When the capacities of the matching heat pump hosts are different, precise control cannot be achieved.

[0003] The above content is only used to assist in understanding the technical solution of the present invention, and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The main purpose of the present invention is to provide a control method and device for a heat pump water heater, a heat pump water heater, and a storage medium, aiming to solve the technical problem that the prior art cannot precisely control the heat pump host.

[0005] To achieve the above purpose, the present invention provides a control method for a heat pump water heater. The control method for the heat pump water heater is applied to a heat pump water heater, which includes a heat pump host, a hydraulic module, and a heat storage module. The heat pump host includes a compressor, a reversing device, an outdoor heat exchanger, an outdoor fan, and an expansion valve. The hydraulic module includes a water pump and a water-fluorine heat exchanger. The heat pump host is connected to the hydraulic module through the water-fluorine heat exchanger. The heat storage module includes a first heat exchange water circuit and a second heat exchange water circuit. The heat storage module is connected to the hydraulic module through the first heat exchange water circuit. The second heat exchange water circuit is connected to the user water pipeline. The first heat exchange water circuit is used for heat storage, and the second heat exchange water circuit is used for heat exchange with the first heat exchange water circuit;

[0006] The control method for the heat pump water heater includes:

[0007] When the heat pump water heater enters the heat storage mode, it is determined whether there is a heat storage energy demand according to the water tank temperature;

[0008] When there is a heat storage energy demand, it is determined whether there is a hot water production energy demand according to the ambient temperature;

[0009] When there is a hot water production energy demand, the hot water production energy demand of the heat pump water heater is adjusted according to a first temperature difference and a second temperature difference. The first temperature difference is used to represent the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger, and the second temperature difference is used to represent the difference between the outlet water temperature and the target outlet water temperature.

[0010] Optionally, when the heat pump water heater enters the heat storage mode, determining whether there is a heat storage energy demand according to the water tank temperature includes:

[0011] When the heat pump water heater enters the heat storage mode, obtaining the water tank temperature;

[0012] Determining the water temperature trend according to the outlet water temperature, where the water temperature trend is one of an upward trend or a downward trend;

[0013] Determining whether there is a heat storage energy demand according to the water temperature trend and the water tank temperature.

[0014] Optionally, the determining whether there is a heat storage energy demand according to the water temperature trend and the water tank temperature includes:

[0015] Collecting the water tank temperature, and obtaining the set water tank temperature and the first dead band temperature;

[0016] Determining whether there is a heat storage energy demand according to the water temperature trend, the water tank temperature, the set water tank temperature and the first dead band temperature; or

[0017] Collecting the water tank temperature, and obtaining the set water tank temperature;

[0018] Determining whether there is a heat storage energy demand according to the water temperature trend, the water tank temperature and the set water tank temperature.

[0019] Optionally, when there is a heat storage energy demand, determining whether there is a hot water heating energy demand according to the ambient temperature includes:

[0020] When there is a heat storage energy demand, detecting the ambient temperature, and determining whether the ambient temperature is in the heating start range;

[0021] Determining whether there is a hot water heating energy demand according to the determination result and the water temperature trend.

[0022] Optionally, the determining whether there is a hot water heating energy demand according to the determination result and the water temperature trend includes:

[0023] Obtaining the highest hot water heating temperature, the target outlet water temperature, the second dead band temperature, the third dead band temperature and the fourth dead band temperature;

[0024] Determining whether there is a hot water heating energy demand according to the determination result, the highest hot water heating temperature, the target outlet water temperature, the second dead band temperature, the third dead band temperature, the fourth dead band temperature and the water temperature trend.

[0025] Optionally, when there is a hot water heating energy demand, adjusting the hot water heating energy demand of the heat pump water heater according to the first temperature difference and the second temperature difference includes:

[0026] When there is a need for hot water heating energy, detect the water-side inlet temperature and the water-side outlet temperature of the water-fluorine heat exchanger, and determine a first temperature difference based on the water-side inlet temperature and the water-side outlet temperature;

[0027] Obtain the target outlet water temperature of the hydraulic module, and determine a second temperature difference based on the outlet water temperature and the target outlet water temperature;

[0028] Calculate the target hot water heating energy demand based on the first temperature difference and the second temperature difference, and adjust the hot water heating energy demand of the heat pump water heater according to the target hot water heating energy demand.

[0029] Optionally, the calculating the target hot water heating energy demand based on the first temperature difference and the second temperature difference includes:

[0030] Query a first coefficient look-up table according to the first temperature difference to determine a first correction coefficient;

[0031] Query a second coefficient look-up table according to the second temperature difference to determine a second correction coefficient;

[0032] Calculate the target hot water heating energy demand based on the first correction coefficient, the second correction coefficient and the rated nominal capacity of the heat pump water heater.

[0033] In addition, to achieve the above object, the present invention also provides a control device for a heat pump water heater. The heat pump water heater includes a heat pump main unit, a hydraulic module and a heat storage module. The heat pump main unit includes a compressor, a reversing device, an outdoor heat exchanger, an outdoor fan and an expansion valve. The hydraulic module includes a water pump and a water-fluorine heat exchanger. The heat pump main unit is connected to the hydraulic module through the water-fluorine heat exchanger. The heat storage module includes a first heat exchange water circuit and a second heat exchange water circuit. The heat storage module is connected to the hydraulic module through the first heat exchange water circuit. The second heat exchange water circuit is connected to a user water pipeline. The first heat exchange water circuit is used for heat storage, and the second heat exchange water circuit is used for heat exchange with the first heat exchange water circuit;

[0034] The control device for the heat pump water heater includes:

[0035] A heat storage energy demand judgment module, configured to judge whether there is a heat storage energy demand according to the water tank temperature when the heat pump water heater enters the heat storage mode;

[0036] A hot water heating energy demand judgment module, configured to judge whether there is a hot water heating energy demand according to the ambient temperature when there is a heat storage energy demand;

[0037] The energy demand adjustment module is used to adjust the hot water production energy demand of the heat pump water heater according to the first temperature difference and the second temperature difference when there is a hot water production energy demand. The first temperature difference is used to characterize the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger, and the second temperature difference is used to characterize the difference between the outlet water temperature and the target outlet water temperature.

[0038] In addition, to achieve the above object, the present invention also proposes a heat pump water heater, which includes: a memory, a processor, and a heat pump water heater program stored on the memory and running on the processor. The heat pump water heater program is configured to implement the heat pump water heater control method as described above.

[0039] In addition, to achieve the above object, the present invention also proposes a storage medium on which a heat pump water heater program is stored. When the heat pump water heater program is executed by a processor, it implements the heat pump water heater control method as described above.

[0040] When the heat pump water heater enters the heat storage mode, the present invention determines whether there is a heat storage energy demand according to the water tank temperature; when there is a heat storage energy demand, it determines whether there is a hot water production energy demand according to the ambient temperature; when there is a hot water production energy demand, it adjusts the hot water production energy demand of the heat pump water heater according to the first temperature difference and the second temperature difference. The first temperature difference is used to characterize the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger, and the second temperature difference is used to characterize the difference between the outlet water temperature and the target outlet water temperature. In this way, after the heat pump water heater enters the heat storage mode, it first determines whether there is a heat storage energy demand and a hot water production energy demand. When there are both a heat storage energy demand and a hot water production energy demand, it adjusts the hot water production energy demand of the heat pump water heater by combining the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger and the difference between the outlet water temperature and the target value, so that the hot water production energy demand of the heat pump water heater can be adjusted in real time according to the working state of the water-fluorine heat exchanger and the deviation between the outlet water temperature and the target value, and the operation and hot water production of the heat pump water heater can be controlled more precisely. Description of the Drawings

[0041] Figure 1 is a schematic structural diagram of a heat pump water heater in the hardware operating environment related to the embodiment solution of the present invention;

[0042] Figure 2 is a schematic flowchart of the first embodiment of the heat pump water heater control method of the present invention;

[0043] Figure 3 is a schematic structural diagram of a heat pump water heater in an embodiment of the heat pump water heater control method of the present invention;

[0044] Figure 4 is a schematic flowchart of the second embodiment of the heat pump water heater control method of the present invention;

[0045] Figure 5 This is the structural block diagram of the first embodiment of the control device for the heat pump water heater of the present invention.

[0046] Explanation of the reference numerals:

[0047]

[0048]

[0049] The realization of the object, functional features and advantages of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed implementation manners

[0050] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0051] Refer to Figure 1 , Figure 1 This is the schematic structural diagram of the heat pump water heater for the hardware operating environment involved in the embodiment solution of the present invention.

[0052] As Figure 1 shown, the heat pump water heater may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display) and an input unit such as a keyboard (Keyboard). Optionally, the user interface 1003 may further include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a wireless-fidelity (Wi-Fi) interface). The memory 1005 may be a high-speed random access memory (Random Access Memory, RAM) or a stable non-volatile memory (Non-Volatile Memory, NVM), such as a disk memory. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0053] Those skilled in the art can understand that Figure 1 the structure shown in

[0054] As Figure 1As shown, the memory 1005 as a storage medium may include an operating system, a network communication module, a user interface module, and a heat pump water heater program.

[0055] In Figure 1 In the heat pump water heater shown, the network interface 1004 is mainly used for data communication with a network server; the user interface 1003 is mainly used for data interaction with a user; the processor 1001 and the memory 1005 in the heat pump water heater of the present invention may be provided in the heat pump water heater. The heat pump water heater calls the heat pump water heater program stored in the memory 1005 through the processor 1001 and executes the heat pump water heater control method provided by the embodiments of the present invention.

[0056] The embodiments of the present invention provide a heat pump water heater control method. Referring to Figure 2 , Figure 2 is a schematic flowchart of the first embodiment of a heat pump water heater control method of the present invention.

[0057] In this embodiment, the heat pump water heater control method includes the following steps:

[0058] Step S10: When the heat pump water heater enters the heat storage mode, determine whether there is a heat storage energy demand according to the water tank temperature.

[0059] In this embodiment, the execution subject of this embodiment may be the heat pump water heater control device. The heat pump water heater control device has functions such as data processing, data communication, and program operation. The heat pump water heater control device may be a controller inside the heat pump water heater. Of course, it may also be other devices with similar functions, and this embodiment does not limit this. For the convenience of description, this embodiment is described by taking the heat pump water heater control device as an example.

[0060] It should be noted that most of the heat pump water heaters on the market at present are storage-type, and the water in the water tank is heated by a heat pump system. The water stored in the water tank is in a "dead water" state. To overcome this drawback, a new phase change heat storage type heat pump water heater has emerged on the market. The phase change heat storage material is filled into the gaps between the heat exchange tubes of the heat storage module of the heat pump water heater, and heat exchange is carried out between the hot water in the tube and the phase change heat storage material to complete the phase change energy storage of the phase change heat storage material, and heat release is carried out again when using hot water to meet the user's demand for using hot water. However, during the energy storage process, it is generally achieved by controlling whether the outlet water temperature of the heat pump reaches the heat storage demand temperature. When the capabilities of the matching heat pump hosts are different, precise control cannot be achieved.

[0061] To solve the above technical problems, in this embodiment, after the heat pump water heater enters the heat storage mode, it is first determined whether there is a heat storage energy demand and a hot water production energy demand. When there are both a heat storage energy demand and a hot water production energy demand, the hot water production energy demand of the heat pump water heater is adjusted by combining the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger and the difference between the outlet water temperature and the target value, so that the hot water production energy demand of the heat pump water heater can be adjusted in real time according to the working state of the water-fluorine heat exchanger and the deviation between the outlet water temperature and the target value, and the operation and hot water production of the heat pump water heater can be controlled more precisely.

[0062] It should be noted that the heat pump water heater mentioned in this embodiment and the following embodiments refers to the Figure 3 phase change heat pump water heater shown as follows. The phase change heat pump water heater includes a heat pump main unit 10, a hydraulic module 20, and a heat storage module 30. The heat pump main unit 10 includes a gas-liquid separator 11, a compressor 12, a reversing device 13, an outdoor heat exchanger 14, an outdoor fan 15, and an expansion valve 16. The hydraulic module 20 includes an electric auxiliary heating device 21, a water flow switch 22, a water pump 23, an expansion tank 24, and a water-fluorine heat exchanger 17. The hydraulic module is also provided with a first sensor 25, and the heat storage module 30 is also provided with a second sensor 33. The first sensor 25 is used to collect the outlet water temperature, and the second sensor 33 is used to collect the temperature of the heat storage module. The heat pump main unit is connected to the hydraulic module through the water-fluorine heat exchanger 17.

[0063] Among them, the outdoor fan 15 is used to reduce the coil temperature of the outdoor heat exchanger 14, thereby accelerating the heat exchange between the heat exchanger and the external environment, and further achieving the control of the heating output capacity of the heat pump main unit 10. The greater the rotation speed of the outdoor fan 15, the greater the heating output of the heat pump main unit 10, and the smaller the rotation speed of the outdoor fan 14, the smaller the heating output capacity of the heat pump main unit 10.

[0064] Among them, the heat storage module includes a first heat exchange water path 31 and a second heat exchange water path 32. The first heat exchange water path 31 and the second heat exchange water path 32 together form a heat storage module heat exchanger. The heat storage module is connected to the hydraulic module 20 through the first heat exchange water path 31. The second heat exchange water path 32 is connected to the user's water pipeline. The first heat exchange water path 31 is used to store heat for the phase change material in the heat storage module, and the second heat exchange water path 32 is used to exchange heat with the first heat exchange water path through the phase change material.

[0065] During the operation of the heat pump main unit in the heat storage mode, the compressor 12 outputs high-temperature and high-pressure refrigerant to the commutation device 13. Through the selected terminal D-C of the commutation device 13, the high-temperature and high-pressure refrigerant exchanges heat through the water-fluorine heat exchanger 17. At this time, the water-fluorine heat exchanger 17 is used as an outdoor heat exchanger. After the refrigerant exchanges heat through the water-fluorine heat exchanger 17, it successively passes through the expansion valve 16, the outdoor heat exchanger 14, the selected terminal E-S of the commutation device 13, and the gas-liquid separator 11 and then returns to the compressor. During this process, since the first side of the water-fluorine heat exchanger 17 is connected to the heat pump main unit and the second side is connected to the hydraulic module, when there is high-temperature and high-pressure refrigerant on the first side of the water-fluorine heat exchanger, due to the temperature difference between the two sides of the water-fluorine heat exchanger, the refrigerant on the first side will heat the water flowing through the second side of the water-fluorine heat exchanger, thereby realizing the heating of the water in the pipeline of the hydraulic module.

[0066] In the hydraulic module, water is sent to the water-fluorine heat exchanger 17 by a water pump, so that the water in the pipeline is heated through the water-fluorine heat exchanger 17, and then successively passes through the electric auxiliary heating device 21 and the water flow switch 22 and flows through the first heat exchange water path 31 of the heat storage module, realizing heat exchange with the phase change material filled in the heat storage module, achieving the purpose of heat storage, and finally returning to the expansion tank 24 or the water pump 23 to participate in the next water-fluorine heat exchange.

[0067] In the heat storage module, tap water enters the second heat exchange pipeline 32 of the heat storage module through the one-way valve in the user water pipeline. The second heat exchange pipeline 32 exchanges heat with the phase change material filled in the heat storage module to achieve the purpose of heating the user's water.

[0068] In this embodiment, the heat pump main unit and the hydraulic module can be integrated into one module, that is, the hydraulic part is included in the heat pump main unit, or they can be separately and independently installed. The heat storage water tank can be a separate heat storage module, or the heat storage module and the hydraulic part can together form the heat storage water tank.

[0069] The heat storage module heat exchanger can be composed of a finned tube heat exchanger and the phase change material filled in its gaps. The finned tube heat exchanger has two water paths. One is connected to the hydraulic module, and the hot water provided by the hydraulic module pipeline flows through the heat storage module heat exchanger or the coil of the heat storage module to exchange heat with the phase change material, realizing the heat charging and energy storage process of the heat storage module. The other is connected to the user water pipeline. When the user uses hot water, tap water is supplemented. The external water body exchanges heat with the phase change material through the second heat exchange water path in the heat storage module heat exchanger, realizing the heat release of the phase change material, achieving the process of heating the user's water, meeting the user's demand for using hot water, and can mix water through the bypass tap water branch to control the water outlet temperature and meet the user's demand for the water temperature of the used water.

[0070] It should be noted that when the heat pump water heater stores heat and stores energy, that is, when the heat storage mode is turned on, the water tank temperature is first detected after the heat storage mode. That is, the temperature detected by the second sensor 33 is used as the water tank temperature. Then, according to the water tank temperature, it is judged whether the heat pump water heater has a heat storage energy demand in the current state. Specifically, it is judged whether there is a heat storage energy demand according to the temperature trend of the water tank temperature. Among them, the heat pump water heater having a heat storage energy demand can be understood as: the heat storage module in the heat pump water heater has a heat storage demand.

[0071] Furthermore, in order to accurately judge whether there is a heat storage energy demand according to the water tank temperature, first, when the heat pump water heater enters the heat storage mode, the water tank temperature is collected by the second sensor 33. Specifically, it includes all the data of the water tank temperature within a certain time period including historical records. The specific time period can be any preset time period, for example: 10 minutes, 30 seconds, etc. Then, the water temperature trend is determined according to the water tank temperature. The water temperature trend includes two types, namely the rising trend and the falling trend. The determined water temperature trend is one of the rising trend or the falling trend. It is worth noting that the initial water temperature remaining unchanged is also included in the rising judgment condition, that is, if the outlet water temperature always remains unchanged at the initial water temperature, it is determined to be a rising trend.

[0072] It should be understood that after obtaining the water temperature trend, it is combined with the water temperature trend and the collected water tank temperature to determine whether there is a heat storage energy demand.

[0073] In a specific implementation, the water tank temperature is the temperature of the heat storage module collected by the second sensor 33.

[0074] Furthermore, in order to determine whether there is a heat storage energy demand according to the water tank temperature and the water temperature trend, first, the water tank temperature needs to be collected, and the preset set water tank temperature and the first dead-band temperature need to be obtained. Among them, the set water tank temperature is the target temperature that the water tank is preset to reach, and the first dead-band temperature is also a temperature value arbitrarily taken from 0°C to 10°C preset. This embodiment does not limit this.

[0075] It should be noted that after obtaining the water temperature trend, first, the situation is classified according to the water temperature trend, and then the water tank temperature is compared with the set water tank temperature, and it is determined whether there is a heat storage energy demand according to the comparison result.

[0076] It should be understood that the specific comparison situation varies according to the water temperature trend. When the water temperature trend is rising, it is not necessary to judge whether there is a need for thermal energy storage through the first dead-band temperature. When the water temperature trend is falling, it is necessary to compare the set water tank temperature minus the first dead-band temperature with the water tank temperature to determine whether there is a need for thermal energy storage. The specific comparison method is as follows: when the outlet water temperature of the heat pump water heater is on the rise, the water tank temperature Tpcm1 ≥ the set water tank temperature indicates no need for thermal energy storage, and the water tank temperature Tpcm1 < the set water tank temperature indicates a need for thermal energy storage. When the outlet water temperature of the heat pump water heater unit is on the decline, the water tank temperature Tpcm1 ≥ the set water tank temperature - the first dead-band temperature indicates no need for thermal energy storage, and the water tank temperature Tpcm1 < the set water tank temperature - the first dead-band temperature indicates a need for thermal energy storage.

[0077] Step S20: When there is a need for thermal energy storage, determine whether there is a need for hot water production according to the ambient temperature.

[0078] In a specific implementation, after determining that the current heat pump water heater has a need for thermal energy storage, it is also necessary to determine whether there is a need for hot water production. The specific determination method is based on the ambient temperature, and the ambient temperature is the ambient temperature of the environment where the heat pump main unit is located. Among them, in step S20, when there is a need for thermal energy storage and the heat pump water heater has a need for hot water production, it can be understood that: the heat storage module has a heat storage demand, and the heat pump water heater can heat the heat storage module.

[0079] Furthermore, in order to accurately determine whether there is a need for hot water production, first detect the ambient temperature, specifically by measuring the temperature of the environment where the heat pump main unit (outdoor unit) is located, and then judge whether the ambient temperature of the heat pump water heater is within the heating start range according to the ambient temperature.

[0080] It should be noted that the heating start range is a pre-set temperature range, which can be a temperature range with any value and any span, and this embodiment does not limit it.

[0081] It should be understood that finally, according to the determination result, that is, whether the ambient temperature is within the heating start range and the current water temperature trend, determine whether there is a need for hot water production;

[0082] Further, in order to accurately determine whether there is a need for hot water heating energy, the steps of determining whether there is a need for hot water heating energy according to the determination result and the water temperature trend are specifically as follows: First, obtain the highest hot water temperature, the target outlet water temperature, the second dead band temperature, the third dead band temperature, and the fourth dead band temperature. Among them, the highest hot water temperature is the temperature of the highest achieved hot water temperature of the heat pump water heater, the target outlet water temperature is the target temperature for providing hot water to users set in advance, and the second dead band temperature is any temperature within the range of 0°C to 10°C, the third dead band temperature is any temperature within the range of 0°C to 10°C, and the fourth dead band temperature is any temperature within the range of 0°C to 10°C. The first dead band temperature, the second dead band temperature, and the third dead band temperature are preferably 2°C, and the fourth dead band temperature is preferably 3°C.

[0083] In specific implementation, the judgment basis for specifically determining whether there is a need for hot water heating energy is that when there is a need for thermal energy storage, the ambient temperature T4 is detected, and it is judged whether the heat pump water heater unit is in the operating heating start range. If it exceeds the range, there is no need for hot water heating energy. If it is in the operating heating start range, the next judgment is carried out. When the outlet water temperature of the heat pump water heater unit is on the rise (the initial water temperature remaining unchanged is also included in the rising judgment condition), the outlet water temperature TW1 of the heat pump water heater unit < Min (the highest hot water temperature TWmaxHW of the heat pump water heater, the target outlet water temperature TWs + the second dead band temperature), there is a need for hot water heating energy, otherwise there is no need; when the outlet water temperature of the heat pump water heater unit is on the decline, the outlet water temperature TW1 of the heat pump water heater unit < Min (the highest hot water temperature TWmaxHW of the heat pump water heater - the third dead band temperature, the target outlet water temperature TWs - the fourth dead band temperature), there is a need for hot water heating energy, otherwise there is no need. The target outlet water temperature can also be a set value.

[0084] Step S30: When there is a need for hot water heating energy, adjust the hot water heating energy of the heat pump water heater according to the first temperature difference and the second temperature difference. The first temperature difference is used to characterize the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger, and the second temperature difference is used to characterize the difference between the outlet water temperature and the target outlet water temperature.

[0085] It should be noted that when it is determined that there is a need for hot water heating energy in the heat pump water heater, the target hot water heating energy of the heat pump water heater is determined according to the first temperature difference and the second temperature difference, and then the operating state of the heat pump water heater is adjusted according to the target hot water heating energy. The adjustment of the hot water heating energy of the heat pump water heater in step S30 can be understood as: adjusting the heat output of the heat pump water heater.

[0086] It should be understood that the first temperature difference is the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger, that is, Figure 3 the temperature at both ends of the right part of the water-fluorine heat exchanger 17 in the hydraulic module 20, that is, the water temperatures at both ends connected to the electric auxiliary heating device 21 and the water pump 23.

[0087] In a specific implementation, the second temperature difference is the difference between the outlet water temperature and the target outlet water temperature, specifically, the difference between the actual current outlet water temperature of the hydraulic module and the target value set for the outlet water temperature.

[0088] In this embodiment, after the heat pump water heater enters the heat storage mode, it first determines whether there is a heat storage energy demand and a hot water production energy demand. When there are both a heat storage energy demand and a hot water production energy demand, the hot water production energy demand of the heat pump water heater is adjusted by combining the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger and the difference between the outlet water temperature and the target value, so that the hot water production energy demand of the heat pump water heater can be adjusted in real time according to the working state of the water-fluorine heat exchanger and the deviation between the outlet water temperature and the target value, and the operation and hot water production of the heat pump water heater can be controlled more precisely.

[0089] Reference Figure 4 , Figure 4 is a schematic flow chart of the second embodiment of a control method for a heat pump water heater according to the present invention.

[0090] Based on the above first embodiment, the control method for the heat pump water heater in this embodiment includes the following in step S30:

[0091] Step S301: When there is a hot water production energy demand, detect the water side inlet temperature and the water side outlet temperature of the water-fluorine heat exchanger, and determine a first temperature difference according to the water side inlet temperature and the water side outlet temperature.

[0092] It should be noted that after it is determined that there is a hot water production energy demand, the water side inlet temperature and the water side outlet temperature of the water-fluorine heat exchanger are first detected to determine the first temperature difference. Specifically, the first temperature difference is the absolute value of the difference between the water side inlet temperature and the water side outlet temperature.

[0093] Step S302: Obtain the target outlet water temperature of the hydraulic module, and determine a second temperature difference according to the outlet water temperature and the target outlet water temperature.

[0094] It should be understood that then the target outlet water temperature of the hydraulic module is obtained. The target outlet water temperature is the preset or calculated outlet water temperature target temperature through the heat storage demand, and then the difference between the current outlet water temperature of the hydraulic module and the target outlet water temperature is determined as the second temperature difference.

[0095] Step S303: Calculate the target hot water production energy demand according to the first temperature difference and the second temperature difference, and adjust the hot water production energy demand of the heat pump water heater according to the target hot water production energy demand.

[0096] In specific implementation, after determining the first temperature difference and the second temperature difference, substitute the first temperature difference and the second temperature difference into the calculation formula for calculation, so as to obtain the target hot water production energy demand, and then modify and adjust the nominal capacity of the heat pump water heater through the target hot water production energy demand, thereby realizing precise control of the heat pump water heater. When there is a hot water production energy demand, according to the temperature difference between the inlet and outlet of the water-side heat exchanger of the current heat pump water heater unit and the difference between the outlet water temperature and the target outlet water temperature, correct the rated nominal capacity Qwhrating of the heat pump water heater unit. The heat pump water heater unit can also be multiple units, and the corrected rated nominal capacity is the sum of the rated nominal capacities of multiple units.

[0097] Further, in order to accurately calculate the target hot water production energy demand, first query the first coefficient comparison table according to the first temperature difference to determine the first correction coefficient. Among them, △T_h is the first temperature difference, which is the temperature difference between the inlet and outlet of the water-side heat exchanger of the heat pump water heater unit; K_△Th is the first correction coefficient, specifically the correction coefficient of the temperature difference △T_h between the inlet and outlet of the water-side heat exchanger of the heat pump water heater unit, obtained by querying the first coefficient comparison table. The first coefficient comparison table is shown in Table 1.

[0098] Table 1

[0099] △T_h K_△Th △T_h < 3.0 °C 1.2 3.0 °C ≤ △T_h < 7.0 °C 1.0 7.0 °C ≤ △T_h < 10.0 °C 0.8 △T_h ≥ 10.0 °C 0.5

[0100] It should be noted that then query the second coefficient comparison table according to the second temperature difference, so as to determine the second correction coefficient. Specifically, △TS_h is the second temperature difference, which is the difference between the outlet water temperature of the heat pump water heater unit and the target outlet water temperature; K_△TSh is the second correction coefficient, that is, the correction coefficient of the difference △TS_h between the outlet water temperature of the heat pump water heater unit and the target outlet water temperature, obtained by querying the second coefficient comparison table. The second coefficient comparison table is shown in Table 2.

[0101] Table 2

[0102] △TS_h K_△TSh △TS_h < -6 °C 1.2 -6 °C ≤ △TS_h < -3 °C 1.05 -3 °C ≤ △TS_h < -1 °C 0.8 -1 °C ≤ △TS_h < 1 °C 0.5 △TS_h ≥ 1 °C 0.4

[0103] Finally, obtain the first correction coefficient and the second correction coefficient, and the calculation formula for the target hot water production energy demand is QWn = Qwhrating * K_△Th * K_△TSh. Finally, control the operation of the heat pump water heater according to the target hot water production energy demand.

[0104] In this embodiment, by judging the heat storage energy demand and the energy demand of the heat pump water heater unit, and according to the temperature difference between the inlet and outlet of the water-side heat exchanger of the current heat pump main unit and the difference between the outlet water temperature and the set temperature, correct the rated nominal capacity of the heat pump main unit, so as to obtain the accurate heat pump operation energy demand, and conduct fine control on the heat storage process, and the control process is more stable and reliable.

[0105] In addition, an embodiment of the present invention further provides a storage medium, on which a heat pump water heater program is stored. When the heat pump water heater program is executed by a processor, the steps of the heat pump water heater control method described above are implemented.

[0106] Since this storage medium adopts all the technical solutions of the above-mentioned all embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here one by one.

[0107] Refer to Figure 5 , Figure 5 which is a structural block diagram of the first embodiment of the heat pump water heater control device of the present invention.

[0108] As Figure 5 shown, the heat pump water heater control device proposed by the embodiment of the present invention includes:

[0109] A thermal energy storage demand judgment module 10, configured to judge whether there is a thermal energy storage demand according to the water tank temperature when the heat pump water heater enters the thermal energy storage mode.

[0110] In this embodiment, the execution subject of this embodiment may be the heat pump water heater control device, which has functions such as data processing, data communication, and program operation. The heat pump water heater control device may be a controller inside the heat pump water heater. Of course, it may also be other devices with similar functions, and this embodiment does not limit this. For the convenience of description, this embodiment is described by taking the heat pump water heater control device as an example.

[0111] It should be noted that most of the heat pump water heaters on the market at present are storage-type, and the water in the water tank is heated by a heat pump system. The water stored in the water tank is in a "stagnant water" state. In order to overcome this drawback, a new phase change thermal energy storage heat pump water heater has emerged on the market. The phase change thermal energy storage material is filled into the gaps between the heat exchange tubes of the thermal energy storage module of the heat pump water heater, and heat exchange is carried out between the hot water in the tube and the phase change thermal energy storage material to complete the phase change energy storage of the phase change thermal energy storage material. When using hot water, heat is released again to meet the user's demand for using hot water. However, during the energy storage process, it is generally achieved by controlling whether the outlet water temperature of the heat pump reaches the heat storage demand temperature. When the matching heat pump host capabilities are different, it cannot be accurately controlled.

[0112] To solve the above technical problems, in this embodiment, after the heat pump water heater enters the heat storage mode, it is first determined whether there is a heat storage energy demand and a hot water production energy demand. When there are both a heat storage energy demand and a hot water production energy demand, the hot water production energy demand of the heat pump water heater is adjusted by combining the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger and the difference between the outlet water temperature and the target value, so that the hot water production energy demand of the heat pump water heater can be adjusted in real time according to the working state of the water-fluorine heat exchanger and the deviation between the outlet water temperature and the target value, and the operation and hot water production of the heat pump water heater can be controlled more precisely.

[0113] It should be noted that the heat pump water heater mentioned in this embodiment and the following embodiments refers to a phase change heat pump water heater as shown in Figure 3 The phase change heat pump water heater includes a heat pump main unit 10, a hydraulic module 20, and a heat storage module 30. The heat pump main unit 10 includes a gas-liquid separator 11, a compressor 12, a reversing device 13, an outdoor heat exchanger 14, an outdoor fan 15, and an expansion valve 16. The hydraulic module 20 includes an electric auxiliary heating device 21, a water flow switch 22, a water pump 23, an expansion tank 24, and a water-fluorine heat exchanger 17. The hydraulic module is also provided with a first sensor 25, and the heat storage module 30 is also provided with a second sensor 33. The first sensor 25 is used to collect the outlet water temperature, and the second sensor 33 is used to collect the temperature of the heat storage module. The heat pump main unit is connected to the hydraulic module through the water-fluorine heat exchanger 17.

[0114] Among them, the outdoor fan 15 is used to reduce the coil temperature of the outdoor heat exchanger 14, thereby accelerating the heat exchange between the heat exchanger and the external environment, and further achieving the control of the heating output capacity of the heat pump main unit 10. The greater the rotation speed of the outdoor fan 15, the greater the heating output of the heat pump main unit 10, and the smaller the rotation speed of the outdoor fan 14, the smaller the heating output capacity of the heat pump main unit 10.

[0115] Among them, the heat storage module includes a first heat exchange water path 31 and a second heat exchange water path 32. The first heat exchange water path 31 and the second heat exchange water path 32 together form a heat storage module heat exchanger. The heat storage module is connected to the hydraulic module 20 through the first heat exchange water path 31. The second heat exchange water path 32 is connected to the user's water use pipeline. The first heat exchange water path 31 is used to store heat for the phase change material in the heat storage module, and the second heat exchange water path 32 is used to exchange heat with the first heat exchange water path through the phase change material.

[0116] During the operation of the heat pump host in the heat storage mode, the compressor 12 outputs high-temperature and high-pressure refrigerant to the commutation device 13. Through the selected terminal D-C of the commutation device 13, the high-temperature and high-pressure refrigerant exchanges heat through the water-fluorine heat exchanger 17. At this time, the water-fluorine heat exchanger 17 is used as the outdoor heat exchanger. After the refrigerant exchanges heat through the water-fluorine heat exchanger 17, it successively passes through the expansion valve 16, the outdoor heat exchanger 14, the selected terminal E-S of the commutation device 13, and the gas-liquid separator 11 and then returns to the compressor. During this process, since the first side of the water-fluorine heat exchanger 17 is connected to the heat pump host and the second side is connected to the hydraulic module, when there is high-temperature and high-pressure refrigerant on the first side of the water-fluorine heat exchanger, due to the temperature difference between the two sides of the water-fluorine heat exchanger, the refrigerant on the first side will heat the water flowing through the second side of the water-fluorine heat exchanger, thereby realizing the heating of the water in the pipeline of the hydraulic module.

[0117] In the hydraulic module, water is sent to the water-fluorine heat exchanger 17 by a water pump, so that the water in the pipeline is heated through the water-fluorine heat exchanger 17, and then successively passes through the electric auxiliary heating device 21 and the water flow switch 22 and flows through the first heat exchange water path 31 of the heat storage module, realizing heat exchange with the phase change material filled in the heat storage module to achieve the purpose of heat storage, and finally returns to the expansion tank 24 or the water pump 23 to participate in the next water-fluorine heat exchange.

[0118] In the heat storage module, tap water enters the second heat exchange pipeline 32 of the heat storage module through the one-way valve in the user water pipeline. The second heat exchange pipeline 32 exchanges heat with the phase change material filled in the heat storage module to raise the temperature of the user's water.

[0119] In this embodiment, the heat pump host and the hydraulic module can be integrated into one module, that is, the hydraulic part is included in the heat pump host, or they can be installed separately and independently. The heat storage water tank can be a separate heat storage module, or the heat storage module and the hydraulic part together form the heat storage water tank.

[0120] The heat exchanger of the heat storage module can be composed of a finned tube heat exchanger and the phase change material filled in its gaps. The finned tube heat exchanger has two water paths. One is connected to the hydraulic module, and the hot water provided by the pipeline of the hydraulic module flows through the heat exchanger of the heat storage module or the coil of the heat storage module to exchange heat with the phase change material, realizing the heat charging and energy storage process of the heat storage module. The other is connected to the user water pipeline. When the user uses hot water, tap water is supplemented. The external water body exchanges heat with the phase change material through the second heat exchange water path in the heat exchanger of the heat storage module, realizing the heat release of the phase change material, achieving the process of raising the temperature of the user's water, meeting the user's demand for using hot water, and can mix water through the bypass tap water branch to control the water outlet temperature and meet the user's demand for the water temperature of the used water.

[0121] It should be noted that when the heat pump water heater stores heat and energy, that is, when the heat storage mode is turned on, the water tank temperature is first detected after the heat storage mode. Specifically, the temperature detected by the second sensor 33 is used as the water tank temperature. Then, according to the outlet water temperature, it is determined whether there is a need for heat storage energy in the heat pump water heater in the current state. Specifically, it is determined whether there is a need for heat storage energy according to the temperature trend of the water tank temperature. Among them, the existence of heat storage energy demand in the heat pump water heater can be understood as: the heat storage module in the heat pump water heater has a heat storage demand.

[0122] Furthermore, in order to accurately determine whether there is a need for heat storage energy according to the water tank temperature, first, when the heat pump water heater enters the heat storage mode, the water tank temperature is collected through the second sensor 33. Specifically, it includes all the data of the outlet water temperature within a certain time period including historical records. The specific time period can be any pre-set time period, such as: 10 minutes, 30 seconds, etc. Then, the water temperature trend is determined according to the water tank temperature. The water temperature trend includes two types, namely the rising trend and the falling trend. The determined water temperature trend is one of the rising trend or the falling trend. It is worth noting that the initial water temperature remaining unchanged is also included in the rising judgment condition, that is, if the outlet water temperature always remains unchanged at the initial water temperature, it is determined as the rising trend.

[0123] It should be understood that after obtaining the water temperature trend, it is combined with the water temperature trend and the collected water tank temperature to determine whether there is a need for heat storage energy.

[0124] In a specific implementation, the water tank temperature is the temperature of the heat storage module collected by the second sensor 33.

[0125] Furthermore, in order to determine whether there is a need for heat storage energy according to the water tank temperature and the water temperature trend, first, the water tank temperature needs to be collected, and the pre-set set water tank temperature and the first dead band temperature are obtained. Among them, the set water tank temperature is the target temperature that the water tank reaches as pre-set, and the first dead band temperature is also a temperature value that can be arbitrarily taken within the range of 0°C to 10°C pre-set. This embodiment does not limit this.

[0126] It should be noted that after obtaining the water temperature trend, first, the situation is classified according to the water temperature trend, and then the water tank temperature is compared with the set water tank temperature, and it is determined whether there is a need for heat storage energy according to the comparison result.

[0127] It should be understood that the specific comparison situation varies according to the water temperature trend. When the water temperature trend is rising, it is not necessary to judge whether there is a need for thermal energy storage through the first dead-band temperature. When the water temperature trend is falling, it is necessary to compare the set water tank temperature minus the first dead-band temperature with the water tank temperature to determine whether there is a need for thermal energy storage. The specific comparison method is as follows: when the water outlet temperature of the heat pump water heater is on the rise, if the water tank temperature Tpcm1 ≥ the set water tank temperature, there is no need for thermal energy storage; if the water tank temperature Tpcm1 < the set water tank temperature, there is a need for thermal energy storage. When the water outlet temperature of the heat pump water heater unit is on the decline, if the water tank temperature Tpcm1 ≥ the set water tank temperature - the first dead-band temperature, there is no need for thermal energy storage; if the water tank temperature Tpcm1 < the set water tank temperature - the first dead-band temperature, there is a need for thermal energy storage.

[0128] The hot water production energy demand judgment module 20 is used to determine whether there is a hot water production energy demand according to the ambient temperature when there is a need for thermal energy storage.

[0129] In a specific implementation, after determining that the current heat pump water heater has a need for thermal energy storage, it is also necessary to judge whether there is a hot water production energy demand. The specific judgment method is to judge according to the ambient temperature, and the ambient temperature is the ambient temperature of the environment where the heat pump main unit is located. Among them, in step S20, when there is a need for thermal energy storage and the heat pump water heater has a hot water production energy demand, it can be understood that: the heat storage module has a heat storage demand, and the heat pump water heater can heat the heat storage module.

[0130] Furthermore, in order to accurately determine whether there is a hot water production energy demand, first detect the ambient temperature, specifically by measuring the temperature of the environment where the heat pump main unit (outdoor unit) is located, and then judge whether the ambient temperature of the heat pump water heater is within the heating start range according to the ambient temperature.

[0131] It should be noted that the heating start range is a pre-set temperature range, which can be a temperature range with any value and any span, and this embodiment does not limit this.

[0132] It should be understood that finally, according to the determination result, that is, whether the ambient temperature is within the heating start range and the current water temperature trend, it is determined whether there is a hot water production energy demand;

[0133] Further, in order to accurately determine whether there is a need for hot water heating energy, the steps of determining whether there is a need for hot water heating energy according to the determination result and the water temperature trend are specifically as follows: First, obtain the highest hot water temperature, the target outlet water temperature, the second dead band temperature, the third dead band temperature, and the fourth dead band temperature. Among them, the highest hot water temperature is the temperature of the highest achieved hot water temperature of the heat pump water heater, the target outlet water temperature is the target temperature for providing hot water to users set in advance, and the second dead band temperature is any temperature within the range of 0°C to 10°C, the third dead band temperature is any temperature within the range of 0°C to 10°C, and the fourth dead band temperature is any temperature within the range of 0°C to 10°C. The first dead band temperature, the second dead band temperature, and the third dead band temperature are preferably 2°C, and the fourth dead band temperature is preferably 3°C.

[0134] In specific implementation, the judgment basis for specifically determining whether there is a need for hot water heating energy is that when there is a need for heat storage energy, detect the ambient temperature T4, and judge whether the heat pump water heater unit is in the operating heating start range. If it exceeds the range, there is no need for hot water heating energy. If it is in the operating heating start range, then proceed to the next judgment. When the outlet water temperature of the heat pump water heater unit is on the rise (the initial water temperature remaining unchanged is also included in the rising judgment condition), the outlet water temperature TW1 of the heat pump water heater unit < Min (the highest hot water temperature TWmaxHW of the heat pump water heater, the target outlet water temperature TWs + the second dead band temperature), there is a need for hot water heating energy, otherwise there is no need; when the outlet water temperature of the heat pump water heater unit is on the decline, the outlet water temperature TW1 of the heat pump water heater unit < Min (the highest hot water temperature TWmaxHW of the heat pump water heater - the third dead band temperature, the target outlet water temperature TWs - the fourth dead band temperature), there is a need for hot water heating energy, otherwise there is no need. The target outlet water temperature can also be a set value.

[0135] The energy demand adjustment module 30 is used to adjust the hot water heating energy demand of the heat pump water heater according to the first temperature difference and the second temperature difference when there is a need for hot water heating energy. The first temperature difference is used to characterize the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger, and the second temperature difference is used to characterize the difference between the outlet water temperature and the target outlet water temperature.

[0136] It should be noted that when it is determined that there is a need for hot water heating energy in the heat pump water heater, the target hot water heating energy demand of the heat pump water heater is determined according to the first temperature difference and the second temperature difference, and then the operating state of the heat pump water heater is adjusted according to the target hot water heating energy demand. The adjustment of the hot water heating energy demand of the heat pump water heater in step S30 can be understood as: adjusting the heat output of the heat pump water heater.

[0137] It should be understood that the first temperature difference is the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger, that is Figure 3 the temperatures at both ends of the right part of the water-fluorine heat exchanger 17 in the hydraulic module 20, that is, the water temperatures at both ends connected to the electric auxiliary heating device 21 and the water pump 23.

[0138] In a specific implementation, the second temperature difference is the difference between the outlet water temperature and the target outlet water temperature, specifically, the difference between the actual outlet water temperature of the current hydraulic module and the target value of the set outlet water temperature.

[0139] In one embodiment, the thermal energy storage demand judgment module 10 is further configured to obtain the water tank temperature when the heat pump water heater enters the thermal energy storage mode; determine the water temperature trend according to the water tank temperature, where the water temperature trend is one of an upward trend or a downward trend; and determine whether there is a thermal energy storage demand according to the water temperature trend and the water tank temperature.

[0140] In one embodiment, the thermal energy storage demand judgment module 10 is further configured to collect the water tank temperature and obtain the set water tank temperature and the first dead band temperature; determine whether there is a thermal energy storage demand according to the water temperature trend, the water tank temperature, the set water tank temperature, and the first dead band temperature; or collect the water tank temperature and obtain the set water tank temperature; and determine whether there is a thermal energy storage demand according to the water temperature trend, the water tank temperature, and the set water tank temperature.

[0141] In one embodiment, the hot water production energy demand judgment module 20 is further configured to detect the ambient temperature when there is a thermal energy storage demand and determine whether the ambient temperature is within the heating start range; and determine whether there is a hot water production energy demand according to the determination result and the water temperature trend.

[0142] In one embodiment, the hot water production energy demand judgment module 20 is further configured to obtain the maximum hot water production temperature, the target outlet water temperature, the second dead band temperature, the third dead band temperature, and the fourth dead band temperature; and determine whether there is a hot water production energy demand according to the determination result, the maximum hot water production temperature, the target outlet water temperature, the second dead band temperature, the third dead band temperature, the fourth dead band temperature, and the water temperature trend.

[0143] In one embodiment, the energy demand adjustment module 30 is further configured to detect the water side inlet temperature and the water side outlet temperature of the water-fluorine heat exchanger when there is a hot water production energy demand and determine the first temperature difference according to the water side inlet temperature and the water side outlet temperature; obtain the target outlet water temperature of the hydraulic module and determine the second temperature difference according to the outlet water temperature and the target outlet water temperature; calculate the target hot water production energy demand according to the first temperature difference and the second temperature difference, and adjust the hot water production energy demand of the heat pump water heater according to the target hot water production energy demand.

[0144] In one embodiment, the energy demand adjustment module 30 is further configured to query a first coefficient look-up table according to the first temperature difference to determine a first correction coefficient; query a second coefficient look-up table according to the second temperature difference to determine a second correction coefficient; and calculate a target hot water production energy demand based on the first correction coefficient, the second correction coefficient, and the rated nominal capacity of the heat pump water heater.

[0145] In this embodiment, after the heat pump water heater enters the heat storage mode, it first determines whether there is a heat storage energy demand and a hot water production energy demand. When there are both a heat storage energy demand and a hot water production energy demand, the hot water production energy demand of the heat pump water heater is adjusted in combination with the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger and the difference between the outlet water temperature and the target value, so that the hot water production energy demand of the heat pump water heater can be adjusted in real time according to the working state of the water-fluorine heat exchanger and the deviation between the outlet water temperature and the target value, and the operation and hot water production of the heat pump water heater can be controlled more precisely.

[0146] It should be understood that the above is only an example for illustration and does not constitute any limitation to the technical solution of the present invention. In specific applications, those skilled in the art can set according to needs, and the present invention does not limit this.

[0147] It should be noted that the above-described work process is only illustrative and does not limit the protection scope of the present invention. In actual applications, those skilled in the art can select some or all of them according to actual needs to achieve the purpose of the solution of this embodiment, and there is no limitation here.

[0148] In addition, for the technical details not described in detail in this embodiment, reference can be made to the heat pump water heater control method provided in any embodiment of the present invention, which will not be elaborated here.

[0149] In addition, it should be noted that in this article, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or system. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or system including that element.

[0150] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments.

[0151] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described example methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as a read-only memory (ROM) / RAM, magnetic disk, optical disk), and includes several instructions for causing a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in various embodiments of the present invention.

[0152] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A control method for a heat pump water heater, characterized in that, The control method of the heat pump water heater is applied to a heat pump water heater, which includes a heat pump main unit, a hydraulic module, and a heat storage module. The heat pump main unit includes a compressor, a reversing device, an outdoor heat exchanger, an outdoor fan, and an expansion valve. The hydraulic module includes a water pump and a water-fluorine heat exchanger. The heat pump main unit is connected to the hydraulic module through the water-fluorine heat exchanger. The heat storage module includes a first heat exchange water circuit and a second heat exchange water circuit. The heat storage module is connected to the hydraulic module through the first heat exchange water circuit. The second heat exchange water circuit is connected to the user's water pipeline. The first heat exchange water circuit is used for heat storage, and the second heat exchange water circuit is used for heat exchange with the first heat exchange water circuit; The control method of the heat pump water heater includes: When the heat pump water heater enters the heat storage mode, determine whether there is a heat storage energy demand according to the water tank temperature; When there is a heat storage energy demand, determine whether there is a hot water production energy demand according to the ambient temperature; When there is a hot water production energy demand, adjust the hot water production energy demand of the heat pump water heater according to a first temperature difference and a second temperature difference. The first temperature difference is used to represent the temperature difference between the inlet and outlet water temperatures on the water side of the water-fluorine heat exchanger, and the second temperature difference is used to represent the difference between the outlet water temperature and the target outlet water temperature.

2. The control method for a heat pump water heater according to claim 1, characterized in that, The step of determining whether there is a heat storage energy demand according to the water tank temperature when the heat pump water heater enters the heat storage mode includes: When the heat pump water heater enters the heat storage mode, obtain the water tank temperature; Determine the water temperature trend according to the water tank temperature. The water temperature trend is one of an upward trend or a downward trend; Determine whether there is a heat storage energy demand according to the water temperature trend and the water tank temperature.

3. The control method for a heat pump water heater according to claim 2, characterized in that, The step of determining whether there is a heat storage energy demand according to the water temperature trend and the water tank temperature includes: Collect the water tank temperature, and obtain the set water tank temperature and the first dead band temperature; Determine whether there is a heat storage energy demand according to the water temperature trend, the water tank temperature, the set water tank temperature, and the first dead band temperature; or Collect the water tank temperature, and obtain the set water tank temperature; Determine whether there is a heat storage energy demand according to the water temperature trend, the water tank temperature, and the set water tank temperature.

4. The control method for a heat pump water heater according to claim 2, characterized in that, The step of determining whether there is a hot water production energy demand according to the ambient temperature when there is a heat storage energy demand includes: When there is a heat storage energy demand, detect the ambient temperature, and determine whether the ambient temperature is within the heat pump heating start range; Determine whether there is a hot water production energy demand according to the determination result and the water temperature trend.

5. The control method for a heat pump water heater according to claim 4, characterized in that, The step of determining whether there is a hot water production energy demand according to the determination result and the water temperature trend includes: Obtain the maximum hot water production temperature, the target outlet water temperature, the second dead band temperature, the third dead band temperature, and the fourth dead band temperature; Determine whether there is a hot water production energy demand according to the determination result, the maximum hot water production temperature, the target outlet water temperature, the second dead band temperature, the third dead band temperature, the fourth dead band temperature, and the water temperature trend.

6. The control method for a heat pump water heater according to claim 1, characterized in that, The step of adjusting the hot water production energy demand of the heat pump water heater according to the first temperature difference and the second temperature difference when there is a hot water production energy demand includes: When there is a demand for hot water heating energy, detect the water-side inlet temperature and the water-side outlet temperature of the water-fluorine heat exchanger, and determine a first temperature difference based on the water-side inlet temperature and the water-side outlet temperature; Obtain the target outlet water temperature of the hydraulic module, and determine a second temperature difference based on the outlet water temperature and the target outlet water temperature; Calculate the target hot water heating energy demand based on the first temperature difference and the second temperature difference, and adjust the hot water heating energy demand of the heat pump water heater according to the target hot water heating energy demand.

7. The control method for a heat pump water heater according to claim 6, characterized in that, The calculating the target hot water heating energy demand based on the first temperature difference and the second temperature difference includes: Query a first coefficient look-up table according to the first temperature difference to determine a first correction coefficient; Query a second coefficient look-up table according to the second temperature difference to determine a second correction coefficient; Calculate the target hot water heating energy demand based on the first correction coefficient, the second correction coefficient and the rated nominal capacity of the heat pump water heater.

8. A control device for a heat pump water heater, characterized in that, The heat pump water heater includes a heat pump main unit, a hydraulic module and a heat storage module. The heat pump main unit includes a compressor, a reversing device, an outdoor heat exchanger, an outdoor fan and an expansion valve. The hydraulic module includes a water pump and a water-fluorine heat exchanger. The heat pump main unit is connected to the hydraulic module through the water-fluorine heat exchanger. The heat storage module includes a first heat exchange water circuit and a second heat exchange water circuit. The heat storage module is connected to the hydraulic module through the first heat exchange water circuit. The second heat exchange water circuit is connected to the user water pipeline. The first heat exchange water circuit is used for heat storage, and the second heat exchange water circuit is used for heat exchange with the first heat exchange water circuit; The heat pump water heater control device includes: A heat storage energy demand judgment module, configured to judge whether there is a heat storage energy demand according to the water tank temperature when the heat pump water heater enters the heat storage mode; A hot water heating energy demand judgment module, configured to judge whether there is a hot water heating energy demand according to the ambient temperature when there is a heat storage energy demand; An energy demand adjustment module, configured to adjust the hot water heating energy demand of the heat pump water heater according to the first temperature difference and the second temperature difference when there is a hot water heating energy demand. The first temperature difference is used to characterize the temperature difference between the water-side inlet and outlet water temperatures of the water-fluorine heat exchanger, and the second temperature difference is used to characterize the difference between the outlet water temperature and the target outlet water temperature.

9. A heat pump water heater, characterized in that, The heat pump water heater includes: a memory, a processor, and a heat pump water heater control program stored on the memory and running on the processor. The heat pump water heater control program is configured to implement the heat pump water heater control method according to any one of claims 1 to 7.

10. A storage medium, characterized in that, A heat pump water heater control program is stored on the storage medium. When the heat pump water heater control program is executed by a processor, it implements the heat pump water heater control method according to any one of claims 1 to 7.

Images