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

Abstract

The invention discloses a heat pump water heater control method and device, a storage medium and a heat pump water heater, and belongs to the technical field of water heaters. After the heat storage mode is started, the current heat storage amount is obtained; the water temperature correction value of the water inlet temperature or the water outlet temperature of the hydraulic module is determined according to the current heat storage amount and the set heat storage amount; according to the water temperature correction value, the target water outlet temperature is determined, the heat pump water heater is controlled to operate according to the target water outlet temperature, and according to the difference value between the current actual heat storage amount and the set needed heat storage amount and the actual heat storage amount change value, the target water temperature correction value is determined; the target water outlet temperature of the heat pump hot water unit is corrected, so that the final target water outlet temperature is obtained, the target automatic water temperature process of the heat pump is finely controlled, and the control process is more stable and reliable.

Description

Technical Field

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

[0002] In the existing technical solutions, most of the heat pump water heaters on the market 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. To overcome this drawback, a new phase change heat storage 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. When using hot water, heat is released again to meet the user's demand for 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 required temperature. Because the heat storage material has a phase change process, it is impossible to accurately control the heat storage amount only by the outlet water temperature.

[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 object of the present invention is to provide a control method, device, storage medium and heat pump water heater for a heat pump water heater, aiming to solve the technical problem that the heat storage amount cannot be accurately controlled only by the outlet water temperature.

[0005] To achieve the above object, the present invention provides a control method 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 the user's water use pipeline. The first heat exchange water circuit is used for heat storage. The second heat exchange water circuit is used for heat exchange with the first heat exchange water circuit and the phase change material. The control method for the heat pump water heater includes the following steps:

[0006] After starting the heat storage mode, obtain the current heat storage amount;

[0007] Determine the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module according to the current heat storage amount and the set heat storage amount; and,

[0008] Determine the target outlet water temperature according to the water temperature correction value, and control the operation of the heat pump water heater according to the target outlet water temperature.

[0009] Optionally, the obtaining of the current heat storage amount includes:

[0010] Detecting the current temperature of the heat storage module;

[0011] Obtaining the phase change temperature of the phase change material; and,

[0012] Determining the current heat storage amount according to the current temperature of the heat storage module and the phase change temperature.

[0013] Optionally, the determining of the current heat storage amount according to the current temperature of the heat storage module and the phase change temperature includes:

[0014] When the current temperature of the heat storage module is greater than the phase change temperature, calculating the liquid sensible heat, the solid sensible heat and the latent heat of phase change according to the initial outlet water temperature, the set temperature of the heat storage module, the mass of the phase change material, the phase change temperature, the liquid specific heat, the solid specific heat and the enthalpy difference of phase change; and,

[0015] Calculating the current heat storage amount according to the liquid sensible heat, the solid sensible heat and the latent heat of phase change.

[0016] Optionally, the determining of the current heat storage amount according to the current temperature of the heat storage module and the phase change temperature includes:

[0017] When the current temperature of the heat storage module is less than or equal to the phase change temperature, calculating the solid sensible heat according to the initial outlet water temperature, the mass of the phase change material, the solid specific heat and the phase change temperature, and taking the solid sensible heat as the current heat storage amount.

[0018] Optionally, the determining of the water temperature correction value according to the current heat storage amount and the set heat storage amount includes:

[0019] Obtaining the difference in heat storage amount between the current heat storage amount and the set heat storage amount;

[0020] Comparing the current heat storage amount with the heat storage amount at the previous moment to obtain the trend of heat storage amount change; and,

[0021] Determining the water temperature correction value according to the difference in heat storage amount and the trend of heat storage amount change.

[0022] Optionally, the determining of the target outlet water temperature according to the water temperature correction value includes:

[0023] When the water temperature correction value is greater than the set threshold, performing positive compensation according to the water temperature correction value to obtain the target outlet water temperature.

[0024] Optionally, the method further includes:

[0025] When the water temperature correction value is less than the set threshold, a negative compensation is performed on the reference outlet water temperature according to the water temperature correction value to obtain the target outlet water temperature, where the reference outlet water temperature is the minimum value among the current actual outlet water temperature, the current automatic water temperature for charging the heat storage module, and the historical target outlet water temperature.

[0026] 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 path and a second heat exchange water path. The heat storage module is connected to the hydraulic module through the first heat exchange water path. The second heat exchange water path is connected to the user water pipe. The first heat exchange water path is used for heat storage, and the second heat exchange water path is used for heat exchange with the first heat exchange water path and the phase change material.

[0027] The control device for the heat pump water heater includes:

[0028] An acquisition module, configured to acquire the current heat storage amount after the heat storage mode is turned on;

[0029] A calculation module, configured to determine a water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module according to the current heat storage amount and the set heat storage amount; and

[0030] A control module, configured to determine the target outlet water temperature according to the water temperature correction value and control the operation of the heat pump water heater according to the target outlet water temperature.

[0031] In addition, to achieve the above object, the present invention also provides a heat pump water heater, which 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 as described above.

[0032] In addition, to achieve the above object, the present invention also provides a storage medium, on which a heat pump water heater control program is stored. When the heat pump water heater control program is executed by a processor, it implements the heat pump water heater control method as described above.

[0033] After the heat storage mode is turned on, the present invention obtains the current heat storage amount; determines the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module according to the current heat storage amount and the set heat storage amount; and determines the target outlet water temperature according to the water temperature correction value, and controls the operation of the heat pump water heater according to the target outlet water temperature. By the above method, according to the difference between the current actual heat storage amount and the set required heat storage amount and the change value of the actual heat storage amount, the determined target water temperature correction value is used to correct the target outlet water temperature of the heat pump water heater unit, so as to obtain the final target outlet water temperature, and the automatic water temperature process of the heat pump target is finely controlled, making the control process more stable and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] 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;

[0035] Figure 2 is a schematic flowchart of the first embodiment of the control method of the heat pump water heater of the present invention;

[0036] Figure 3 is a schematic structural diagram of a phase change water heater in an embodiment of the control method of the heat pump water heater of the present invention;

[0037] Figure 4 is a schematic flowchart of the second embodiment of the control method of the heat pump water heater of the present invention;

[0038] Figure 5 is a schematic flowchart of the third embodiment of the control method of the heat pump water heater of the present invention;

[0039] Figure 6 is a structural block diagram of the first embodiment of the control device of the heat pump water heater of the present invention.

[0040] DESCRIPTION OF THE REFERENCE NUMERALS:

[0041] Label Name Label Name 10 Heat pump main unit 17 Water-fluorine heat exchanger 20 Hydraulic module 21 Electric auxiliary heating device 30 Heat storage module 22 Flow switch 11 Gas-liquid separator 23 Water pump 12 Compressor 24 Expansion tank 13 Reversing device 25 First sensor 14 Outdoor heat exchanger 31 First heat exchange water circuit 15 Outdoor fan 32 Second heat exchange water circuit 16 Expansion valve 33 Second sensor

[0042] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] 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.

[0044] Refer to Figure 1 , 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.

[0045] Such as Figure 1As shown in the figure, 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 and an input unit such as a 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 (RAM) or a stable 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.

[0046] Those skilled in the art can understand that Figure 1 the structure shown in the figure does not constitute a limitation on the heat pump water heater, and it may include more or fewer components than shown in the figure, or combine some components, or have different component arrangements.

[0047] As Figure 1 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 control program.

[0048] In Figure 1 the heat pump water heater shown in the figure, 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 users; the processor 1001 and the memory 1005 in the heat pump water heater of the present invention may be arranged in the heat pump water heater. The heat pump water heater calls the heat pump water heater control 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.

[0049] The embodiments of the present invention provide a heat pump water heater control method. Referring to Figure 2 , Figure 2 it is a schematic flowchart of the first embodiment of a heat pump water heater control method of the present invention.

[0050] In this embodiment, the heat pump water heater control method includes the following steps:

[0051] Step S10: After the heat storage mode is turned on, obtain the current heat storage amount.

[0052] In this embodiment, the execution subject of this embodiment can 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 can be the controller inside the heat pump water heater. Of course, it can 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.

[0053] It should be noted that in the existing technical solutions, most of the heat pump water heaters on the market are storage-type, and the water in the water tank is heated by the heat pump system. The water stored in the water tank is in a "stagnant water" state. To overcome this drawback, a new phase change heat storage 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. When using hot water, heat is released again to meet the user's demand for 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 required temperature. Because the heat storage material has a phase change process, it is impossible to accurately control the heat storage amount only by the outlet water temperature.

[0054] To solve the above technical problems, in this embodiment, after the heat storage mode is turned on, the current heat storage amount is obtained; the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module is determined according to the current heat storage amount and the set heat storage amount; and, the target outlet water temperature is determined according to the water temperature correction value, and the heat pump water heater is controlled to operate according to the target outlet water temperature. By the above method, according to the difference between the current actual heat storage amount and the set required heat storage amount and the change value of the actual heat storage amount, the determined target water temperature correction value is used to correct the target outlet water temperature of the heat pump water heater unit, so as to obtain the final target outlet water temperature, and the target automatic water temperature process of the heat pump is finely controlled, making the control process more stable and reliable. Specifically, it can be implemented in the following manner.

[0055] It is worth noting that the heat pump water heater mentioned in this embodiment and the following embodiments refers to Figure 3 the phase change heat pump water heater shown in the figure. 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 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.

[0056] 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 host 10. The greater the rotational speed of the outdoor fan 15, the greater the heating output of the heat pump host 10, and the smaller the rotational speed of the outdoor fan 14, the smaller the heating output capacity of the heat pump host 10.

[0057] 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 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 and the phase change material.

[0058] 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 an outdoor heat exchanger. After the refrigerant exchanges heat through the water-fluorine heat exchanger 17, it sequentially 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 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 in the hydraulic module.

[0059] 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 sequentially 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 to realize 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.

[0060] In the heat storage module, tap water enters the second heat exchange pipeline 32 of the heat storage module through the check valve in the user water pipeline, and 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 water.

[0061] 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 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 can together form the heat storage water tank.

[0062] The heat storage module heat exchanger can be composed of a finned tube heat exchanger and a phase change material filled in its gaps. There are two water circuits in the finned tube heat exchanger. 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, and exchanges heat with the phase change material to realize the heat charging and energy storage process of the heat storage module. The other is connected to the user's 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 circuit in the heat storage module heat exchanger to realize the heat release of the phase change material, so as to increase the temperature of the user's water use, meet 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 water use.

[0063] In specific implementation, in this embodiment, it is necessary to first detect whether the heat pump water heater has enabled the heat storage mode. After enabling the heat storage mode, the current heat storage amount is obtained in this embodiment. The current heat storage amount can be determined by parameters such as the parameters of the phase change material, the outlet water temperature, and the temperature of the heat storage module itself.

[0064] Step S20: Determine the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module according to the current heat storage amount and the set heat storage amount.

[0065] In specific implementation, after obtaining the current heat storage amount of the heat pump water heater, in this embodiment, it is necessary to combine the current heat storage amount and the set heat storage amount to determine the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module. The set heat storage amount in this embodiment can be calculated from the set water tank temperature, the mass of the phase change material, the phase change temperature Tpc, the liquid specific heat, the solid specific heat, the phase change enthalpy difference, and the initial outlet water temperature. For example, QS = Q1 + Q2 + Q3, the liquid sensible heat Q1 = mc1(TSpcm - Tpc), the solid sensible heat Q2 = mc2(Tpc - T0), the phase change latent heat Q3 = mΔH, where QS represents the set heat storage amount, m represents the mass of the phase change material, c1 represents the liquid specific heat, c2 represents the solid specific heat, Tpc represents the phase change temperature, ΔH represents the phase change enthalpy difference, TSpcm represents the set water tank temperature, that is, the set temperature of the heat storage module, and T0 represents the initial outlet water temperature.

[0066] Further, in this embodiment, the heat storage difference between the current heat storage amount and the set heat storage amount can be calculated, and then the current heat storage amount is compared with the heat storage amount at the previous moment. Based on the magnitude relationship between the current heat storage amount and the heat storage amount at the previous moment, the heat storage change trend corresponding to the current heat storage amount is determined. For example, if the current heat storage amount is greater than the heat storage amount at the previous moment, the corresponding heat storage change trend is an upward trend. Based on this change trend, in this embodiment, the change value between the current heat storage amount and the heat storage amount at the previous moment can also be obtained. For example, the change value △E_Qn = Qn(n) - Qn(n - 1), where Qn(n) represents the current heat storage amount and Qn(n - 1) represents the heat storage amount at the previous moment. The heat storage difference between the current heat storage amount and the set heat storage amount is, for example, E_Qn = Qn - QS, where Qn represents the current heat storage amount and QS represents the set heat storage amount. Based on the above △E_Qn and E_Qn, the water temperature correction value can be determined.

[0067] Step S30: Determine the target outlet water temperature according to the water temperature correction value, and control the operation of the heat pump water heater according to the target outlet water temperature.

[0068] In a specific implementation, after determining the water temperature correction value, in this embodiment, the currently set target outlet water temperature can be corrected according to this water temperature correction value to obtain the final target outlet water temperature. Finally, the heat pump water heater can operate according to the target outlet water temperature.

[0069] In this embodiment, after the heat storage mode is turned on, the current heat storage amount is obtained; the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module is determined according to the current heat storage amount and the set heat storage amount; and, the target outlet water temperature is determined according to the water temperature correction value, and the operation of the heat pump water heater is controlled according to the target outlet water temperature. By the above method, according to the difference between the current actual heat storage amount and the set required heat storage amount and the actual heat storage change value, the determined target water temperature correction value is used to correct the target outlet water temperature of the heat pump water heater unit, so as to obtain the final target outlet water temperature, and the target automatic water temperature process of the heat pump is finely controlled, making the control process more stable and reliable.

[0070] Reference Figure 4 , Figure 4 is a schematic flowchart of the second embodiment of a control method for a heat pump water heater according to the present invention.

[0071] Based on the above first embodiment, in the control method of the heat pump water heater in this embodiment, the step S10 specifically includes:

[0072] Step S101: Detect the current temperature of the heat storage module.

[0073] In this embodiment, the heat storage module is provided with a second sensor, and the current temperature of the heat storage module can be collected through the second sensor.

[0074] Step S102: Obtain the phase change temperature of the phase change material.

[0075] In a specific implementation, the heat pump water heater in this solution is a phase change water heater. The phase change water heater exchanges heat through the phase change material to achieve heat charging and energy storage. When determining the current heat storage amount, it is necessary to obtain the phase change temperature of the phase change material.

[0076] Step S103: Determine the current heat storage amount according to the current heat storage module temperature and the phase change temperature.

[0077] In a specific implementation, based on the magnitude relationship between the current heat storage module temperature and the phase change temperature, different methods will be used in this embodiment to determine the current heat storage amount.

[0078] If the current heat storage module temperature is greater than the phase change temperature, in this embodiment, the current heat storage amount is calculated according to the initial water outlet temperature, the set heat storage module temperature, the mass of the phase change material, the phase change temperature, the liquid specific heat, the solid specific heat, and the phase change enthalpy difference. Specifically, the liquid sensible heat, the solid sensible heat, and the latent heat of phase change can be calculated according to the above parameters. For example, the liquid sensible heat Q1n = mc1(Tpcm1 - Tpc), Q2n = mc2(Tpc - T0), Q3n = mΔH, where m represents the mass of the phase change material, c1 represents the liquid specific heat, c2 represents the solid specific heat, Tpc represents the phase change temperature, ΔH represents the phase change enthalpy difference, TSpcm1 represents the current heat storage module temperature, and T0 represents the initial water outlet temperature. Finally, the current heat storage amount can be obtained according to the liquid sensible heat, the solid sensible heat, and the latent heat of phase change. The current heat storage amount Qn = Q1n + Q2n + Q3n.

[0079] If the current heat storage module temperature is less than or equal to the phase change temperature, in this embodiment, the current heat storage amount is calculated according to the initial water outlet temperature, the mass of the phase change material, the solid specific heat, and the phase change temperature. Specifically, the solid sensible heat can be calculated according to the initial water outlet temperature, the mass of the phase change material, the solid specific heat, and the phase change temperature. For example, Q2n = mc2(Tpc - T0), and the parameter meanings are as described above and will not be elaborated here. At this time, the solid sensible heat is the current heat storage amount.

[0080] In this embodiment, by detecting the current heat storage module temperature, obtaining the phase change temperature of the phase change material, and determining the current heat storage amount according to the current heat storage module temperature and the phase change temperature, and selecting different methods to calculate the current heat storage amount based on the magnitude relationship between the current heat storage module temperature and the phase change temperature, the accurate actual heat storage amount of the heat pump water heater can be obtained for different scenarios through the above method, so as to ensure the correction accuracy of the subsequent water outlet temperature.

[0081] Reference Figure 5 , Figure 5Schematic flowchart of the third embodiment of a control method for a heat pump water heater according to the present invention.

[0082] Based on the above first embodiment, a third embodiment of a control method for a heat pump water heater according to the present invention is proposed.

[0083] In this embodiment, step S30 further includes:

[0084] Step S301: When the water temperature correction value is greater than the set threshold, perform positive compensation according to the water temperature correction value to obtain the target outlet water temperature.

[0085] It should be noted that after obtaining the water temperature correction value based on the difference between the actual heat storage amount and the set heat storage amount and the change value of the implemented heat storage amount, in this embodiment, compensation can be performed according to the water temperature correction value to obtain the target outlet water temperature.

[0086] In specific implementation, in this embodiment, the water temperature correction value is first compared with the set threshold, where the set threshold can be set to 0. If the water temperature correction value is greater than the set threshold, that is, when the water temperature correction value is greater than 0, in this embodiment, positive compensation is performed based on the current heat storage module charging automatic water temperature according to the water temperature correction value to obtain the target outlet water temperature. For example, when ΔTWsB>0, TWsB = TWsO + ΔTWsB, where TWsB represents the target outlet water temperature and TWsO represents the current heat storage module charging automatic water temperature. If the water temperature correction value is less than the set threshold, that is, when the water temperature correction value is less than 0, in this embodiment, negative compensation is performed based on the reference outlet water temperature according to the water temperature correction value to obtain the target outlet water temperature. For example, TWsB = ΔTWsB + TW 1 , where TW 1＝ min(TWsr, TWsO, TWsB(n - 1)), ΔTWsB represents the water temperature correction value, TW 1 represents the reference outlet water temperature, TWsr represents the current actual outlet water temperature, TWsO represents the current heat storage module charging automatic water temperature, and TWsB(n - 1) represents the historical target outlet water temperature, which can be the target outlet water temperature calculated by the previous control algorithm.

[0087] In this embodiment, when the water temperature correction value is greater than the set threshold, positive compensation is performed according to the water temperature correction value to obtain the target outlet water temperature, and when the water temperature correction value is less than the set threshold, negative compensation is performed on the reference outlet water temperature according to the water temperature correction value to obtain the target outlet water temperature. Different compensation methods are adopted according to the magnitude of the water temperature correction value to obtain the target outlet water temperature. Through the above method, an accurate outlet water temperature can be obtained based on the change of the actual heat storage amount, and the heat pump target automatic water temperature process can be finely controlled, making the control process more stable and reliable.

[0088] In addition, an embodiment of the present invention further provides a storage medium, on which a heat pump water heater control program is stored. When the heat pump water heater control program is executed by a processor, the steps of the heat pump water heater control method described above are implemented.

[0089] Since this storage medium adopts all the technical solutions of the above-mentioned all embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated one by one here.

[0090] Refer to Figure 6 , Figure 6 which is a structural block diagram of the first embodiment of the heat pump water heater control device of the present invention.

[0091] As Figure 6 shown, the heat pump water heater control device proposed by the embodiment of the present invention includes:

[0092] An acquisition module 100, configured to acquire the current heat storage amount after the heat storage mode is turned on.

[0093] It should be noted that in the prior art solutions, most heat pump water heaters on the market are storage-type, and the water in the water tank is heated by a heat pump system, and 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 is released when using hot water to meet the user's demand for 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 required temperature. Because the heat storage material has a phase change process, the heat storage amount cannot be accurately controlled only by the outlet water temperature.

[0094] To solve the above technical problems, in this embodiment, after the heat storage mode is turned on, the current heat storage amount is acquired; the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module is determined according to the current heat storage amount and the set heat storage amount; and, the target outlet water temperature is determined according to the water temperature correction value, and the heat pump water heater is controlled to operate according to the target outlet water temperature. By the above method, according to the difference between the current actual heat storage amount and the set required heat storage amount and the change value of the actual heat storage amount, the determined target water temperature correction value is used to correct the target outlet water temperature of the heat pump water heater unit, so as to obtain the final target outlet water temperature, and the target automatic water temperature process of the heat pump is finely controlled, making the control process more stable and reliable. Specifically, it can be implemented in the following manner.

[0095] It is worth noting that the heat pump water heater mentioned in this embodiment and the following embodiments refers to such as Figure 3The phase change heat pump water heater shown, 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 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.

[0096] 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 rotational speed of the outdoor fan 15, the greater the heating output of the heat pump main unit 10, and the smaller the rotational speed of the outdoor fan 14, the smaller the heating output capacity of the heat pump main unit 10.

[0097] 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 and the phase change material.

[0098] 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 reversing device 13. Through the selected terminal D-C of the reversing 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 sequentially passes through the expansion valve 16, the outdoor heat exchanger 14, the selected terminal E-S of the reversing device 13 and the gas-liquid separator 11 and 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.

[0099] In the hydraulic module, water is supplied to the water-fluorine heat exchanger 17 by a water pump, so that the water in the pipeline passes through the water-fluorine heat exchanger 17 for heating, 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 flowing back to the expansion tank 24 or the water pump 23 to participate in the next water-fluorine heat exchange.

[0100] In the heat storage module, tap water enters the second heat exchange water path 32 of the heat storage module through the one-way valve in the user water pipeline. The second heat exchange water path 32 exchanges heat with the phase change material filled in the heat storage module to raise the temperature of the user's water.

[0101] 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 can together form the heat storage water tank.

[0102] 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. There are two water paths in the finned tube heat exchanger. One is connected to the hydraulic module, and the hot water provided by the hydraulic module pipeline 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 outlet water temperature and meet the user's demand for the water temperature of the used water.

[0103] In the specific implementation, in this embodiment, it is necessary to first detect whether the heat pump water heater has enabled the heat storage mode. After enabling the heat storage mode, in this embodiment, the current heat storage amount is obtained. The current heat storage amount can be determined by parameters such as the parameters of the phase change material, the outlet water temperature, and the temperature of the heat storage module itself.

[0104] The calculation module 200 is used to determine the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module according to the current heat storage amount and the set heat storage amount.

[0105] In a specific implementation, after obtaining the current heat storage amount of the heat pump water heater, in this embodiment, it is necessary to combine the current heat storage amount with the set heat storage amount to determine the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module. The set heat storage amount in this embodiment can be calculated from the set water tank temperature, the mass of the phase change material, the phase change temperature Tpc, the liquid specific heat, the solid specific heat, the phase change enthalpy difference, and the initial outlet water temperature. For example, QS = Q1 + Q2 + Q3, the liquid sensible heat Q1 = mc1(TSpcm - Tpc), the solid sensible heat Q2 = mc2(Tpc - T0), the latent heat of phase change Q3 = mΔH, where QS represents the set heat storage amount, m represents the mass of the phase change material, c1 represents the liquid specific heat, c2 represents the solid specific heat, Tpc represents the phase change temperature, ΔH represents the phase change enthalpy difference, TSpcm represents the set water tank temperature, that is, the set temperature of the heat storage module, and T0 represents the initial outlet water temperature.

[0106] Further, in this embodiment, the heat storage amount difference between the current heat storage amount and the set heat storage amount can be calculated, and then the current heat storage amount is compared with the heat storage amount at the previous moment. Based on the magnitude between the current heat storage amount and the heat storage amount at the previous moment, the heat storage amount change trend corresponding to the current heat storage amount is determined. For example, if the current heat storage amount is greater than the heat storage amount at the previous moment, the corresponding heat storage amount change trend is an upward trend. Based on this change trend, in this embodiment, the change value between the current heat storage amount and the heat storage amount at the previous moment can also be obtained. For example, the change value △E_Qn = Qn(n) - Qn(n - 1), where Qn(n) represents the current heat storage amount, Qn(n - 1) represents the heat storage amount at the previous moment, and the heat storage amount difference between the current heat storage amount and the set heat storage amount is, for example, E_Qn = Qn - QS, Qn represents the current heat storage amount, and QS represents the set heat storage amount. Based on the above △E_Qn and E_Qn, the water temperature correction value can be determined.

[0107] The control module 300 is configured to determine a target outlet water temperature according to the water temperature correction value and control the operation of the heat pump water heater according to the target outlet water temperature.

[0108] In a specific implementation, after determining the water temperature correction value, in this embodiment, the currently set target outlet water temperature can be corrected according to the water temperature correction value to obtain the final target outlet water temperature. Finally, the heat pump water heater can operate according to the target outlet water temperature.

[0109] In this embodiment, after the heat storage mode is turned on, the current heat storage amount is obtained; a water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module is determined according to the current heat storage amount and the set heat storage amount; and, a target outlet water temperature is determined according to the water temperature correction value, and the heat pump water heater is controlled to operate according to the target outlet water temperature. By the above method, according to the difference between the current actual heat storage amount and the set required heat storage amount and the change value of the actual heat storage amount, the determined target water temperature correction value is used to correct the target outlet water temperature of the heat pump water heater unit, so as to obtain the final target outlet water temperature, and the automatic water temperature process of the heat pump target is finely controlled, making the control process more stable and reliable.

[0110] In one embodiment, the obtaining module 100 is further configured to detect the current temperature of the heat storage module; obtain the phase change temperature of the phase change material; and determine the current heat storage amount according to the current temperature of the heat storage module and the phase change temperature.

[0111] In one embodiment, when the current temperature of the heat storage module is greater than the phase change temperature, the obtaining module 100 is further configured to calculate the sensible heat of the liquid state, the sensible heat of the solid state, and the latent heat of phase change according to the initial outlet water temperature, the set temperature of the heat storage module, the mass of the phase change material, the phase change temperature, the specific heat of the liquid state, the specific heat of the solid state, and the phase change enthalpy difference; and calculate the current heat storage amount according to the sensible heat of the liquid state, the sensible heat of the solid state, and the latent heat of phase change.

[0112] In one embodiment, when the current temperature of the heat storage module is less than or equal to the phase change temperature, the obtaining module 100 is further configured to calculate the sensible heat of the solid state according to the initial outlet water temperature, the mass of the phase change material, the specific heat of the solid state, and the phase change temperature, and use the sensible heat of the solid state as the current heat storage amount.

[0113] In one embodiment, the calculating module 200 is further configured to obtain the difference in heat storage amount between the current heat storage amount and the set heat storage amount; compare the current heat storage amount with the heat storage amount at the previous moment to obtain the change trend of the heat storage amount; and determine the water temperature correction value according to the difference in heat storage amount and the change trend of the heat storage amount.

[0114] In one embodiment, when the water temperature correction value is greater than the set threshold, the control module 300 is further configured to perform positive compensation according to the water temperature correction value to obtain the target outlet water temperature.

[0115] In one embodiment, when the water temperature correction value is less than the set threshold, the control module 300 is further configured to perform negative compensation on the reference outlet water temperature according to the water temperature correction value to obtain the target outlet water temperature, where the reference outlet water temperature is the minimum value among the current actual outlet water temperature, the current heat storage module charging automatic water temperature, and the historical target outlet water temperature.

[0116] It should be understood that the above is only for illustration purposes and does not constitute any limitation to the technical solution of the present invention. In specific applications, those skilled in the art can set it according to needs, and the present invention does not limit this.

[0117] 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.

[0118] 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, and details will not be repeated here.

[0119] In addition, it should be noted that in this article, the term "comprising", "including" or any other variant thereof is 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 also includes elements inherent to such process, method, article or system. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of another identical element in the process, method, article or system including that element.

[0120] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0121] Through the description of the above embodiments, those skilled in the art can clearly understand that the above embodiment 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 method. 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.

[0122] 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 specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be included in the patent protection scope of the present invention by the same token.

[0123] It should be understood that although the steps in the flowchart in the embodiments of the present application are sequentially shown according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps has no strict order restriction, and they can be executed in other orders. Moreover, at least a part of the steps in the figure may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be executed alternately or alternately with at least a part of other steps or sub-steps or stages of other steps.

Claims

1. A control method 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 pipe. The first heat exchange water circuit is used for heat storage. The second heat exchange water circuit is used for heat exchange with the first heat exchange water circuit and the phase change material; the control method for the heat pump water heater includes: after the heat storage mode is turned on, obtaining the current heat storage amount; determining a water temperature correction value for the inlet water temperature or the outlet water temperature of the hydraulic module according to the current heat storage amount and the set heat storage amount; and, determining a target outlet water temperature according to the water temperature correction value and controlling the operation of the heat pump water heater according to the target outlet water temperature.

2. The control method for the heat pump water heater according to claim 1, characterized in that, the obtaining of the current heat storage amount includes: detecting the current temperature of the heat storage module; obtaining the phase change temperature of the phase change material; and, determining the current heat storage amount according to the current temperature of the heat storage module and the phase change temperature.

3. The control method for the heat pump water heater according to claim 2, characterized in that, the determining of the current heat storage amount according to the current temperature of the heat storage module and the phase change temperature includes: when the current temperature of the heat storage module is greater than the phase change temperature, calculating the liquid sensible heat, the solid sensible heat and the latent heat of phase change according to the initial outlet water temperature, the set temperature of the heat storage module, the mass, the phase change temperature, the liquid specific heat, the solid specific heat and the phase change enthalpy difference of the phase change material; and, calculating the current heat storage amount according to the liquid sensible heat, the solid sensible heat and the latent heat of phase change.

4. The control method for the heat pump water heater according to claim 2, characterized in that, the determining of the current heat storage amount according to the current temperature of the heat storage module and the phase change temperature includes: when the current temperature of the heat storage module is less than or equal to the phase change temperature, calculating the solid sensible heat according to the initial outlet water temperature, the mass, the solid specific heat and the phase change temperature of the phase change material, and taking the solid sensible heat as the current heat storage amount.

5. The control method for the heat pump water heater according to claim 1, characterized in that, the determining of the water temperature correction value according to the current heat storage amount and the set heat storage amount includes: obtaining the difference in heat storage amount between the current heat storage amount and the set heat storage amount; comparing the current heat storage amount with the heat storage amount at the previous moment to obtain the trend of change in heat storage amount; and, determining the water temperature correction value according to the difference in heat storage amount and the trend of change in heat storage amount.

6. The control method for the heat pump water heater according to claim 1, characterized in that, the determining of the target outlet water temperature according to the water temperature correction value includes: when the water temperature correction value is greater than the set threshold, performing positive compensation according to the water temperature correction value to obtain the target outlet water temperature.

7. The control method for the heat pump water heater according to claim 6, Characterized in that, The method further includes: When the water temperature correction value is less than the set threshold, negatively compensate the reference outlet water temperature according to the water temperature correction value to obtain the target outlet water temperature, and the reference outlet water temperature is the minimum value among the current actual outlet water temperature, the current heat storage module charging automatic water temperature, and the historical target outlet water temperature.

8. A heat pump water heater control device, 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 path and a second heat exchange water path. The heat storage module is connected to the hydraulic module through the first heat exchange water path. The second heat exchange water path is connected to the user water pipe. The first heat exchange water path is used for heat storage, and the second heat exchange water path is used for heat exchange with the first heat exchange water path and the phase change material; The heat pump water heater control device includes: An acquisition module, configured to acquire the current heat storage amount after the heat storage mode is turned on; A calculation module, configured to determine the water temperature correction value of the inlet water temperature or the outlet water temperature of the hydraulic module according to the current heat storage amount and the set heat storage amount; and, A control module, configured to determine the target outlet water temperature according to the water temperature correction value and control the operation of the heat pump water heater according to 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, The storage medium stores a heat pump water heater control program, and 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.

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