Defrosting control method, device, equipment and medium for heat pump water heater

Abstract

The present application belongs to the field of intelligent household appliances, and particularly relates to a defrosting control method, device, equipment and medium of a heat pump water heater. The present application aims to solve the problem of how to defrost in the process of heating water for a new air source heat pump water heater. The defrosting control method, device, equipment and medium of the heat pump water heater provided by the present application determine different defrosting schemes according to the temperature of the water tank when the outdoor heat exchanger needs to be defrosted. When the temperature of the water tank is high, more high-temperature and high-pressure refrigerant flows to the outdoor heat exchanger for defrosting; when the temperature of the water tank is low, more high-temperature and high-pressure refrigerant flows to the water tank for heating the water in the water tank. The present application realizes defrosting while heating water by controlling the amount of refrigerant flowing to the outdoor heat exchanger and the water tank, and the energy distribution optimization degree of heating water and defrosting is relatively high.

Description

Technical Field

[0001] The embodiments of the present invention belong to the field of smart home appliances, specifically relating to the defrosting control method, device, equipment and medium for heat pump water heaters. Background Technology

[0002] With the development of technology and the improvement of people's living standards, the number and types of home appliances in people's homes are increasing, such as water heaters, air conditioners, refrigerators, and washing machines. As for water heaters, they have evolved from the original electric water heaters and gas water heaters to the current air source heat pump water heaters.

[0003] In existing technologies, traditional air source heat pump water heaters typically only include hot water production, while indoor cooling and heating are usually handled by separate cooling and heating equipment. This not only results in low equipment utilization rates for traditional air source heat pump water heaters and cooling / heating equipment, but also occupies a large installation space, leading to low space utilization. To address this, related technologies provide a novel air source heat pump water heater that integrates hot water production, cooling, and heating functions into one unit, giving it a multi-functional feature and improving both equipment and space utilization.

[0004] However, how to defrost the new air source heat pump water heater during the hot water production process still needs further research. Summary of the Invention

[0005] In order to solve the above-mentioned problems in the prior art, namely, how to defrost a new type of air source heat pump water heater during the hot water production process, the present invention provides a defrosting control method, device, equipment and medium for a heat pump water heater.

[0006] In a first aspect, embodiments of the present invention provide a defrosting control method for a heat pump water heater, applied to a processor in the heat pump water heater. The heat pump water heater includes the processor, a water tank, and a hot water heat exchanger, an electric heater, a compressor, an indoor heat exchanger, an outdoor heat exchanger, and a control valve assembly connected to the processor. The control valve assembly includes a four-way reversing valve, a main control valve, a hot water control valve, and a heating control valve. The compressor is connected to the outdoor heat exchanger and the indoor heat exchanger respectively through the four-way reversing valve. The indoor heat exchanger is connected to the hot water heat exchanger through the heating control valve and the hot water control valve. The hot water heat exchanger is connected to the water tank for heating the water tank. The hot water heat exchanger is connected to the outdoor heat exchanger through the hot water control valve and the main control valve. The electric heater is located inside the water tank for electrically heating the water tank. The method includes:

[0007] When the preset defrosting conditions are met, the temperature of the water tank is obtained;

[0008] The operating status of each control valve in the compressor, the electric heater, and the control valve assembly is controlled according to the temperature of the water tank and the preset water tank temperature.

[0009] In the preferred embodiment of the defrosting control method for the above-mentioned heat pump water heater, the step of controlling the operating state of the compressor, the electric heater, and each control valve in the control valve assembly according to the temperature of the water tank and the preset water tank temperature includes:

[0010] When the temperature of the water tank is greater than or equal to the preset water tank temperature, the first hot water opening degree of the hot water control valve, the first control opening degree of the main control valve, the heating opening degree of the heating control valve, the working state of the electric heater, the connection direction of the four-way reversing valve, and the working frequency of the compressor are determined.

[0011] The system controls the hot water control valve to be at the first hot water opening degree, the main control valve to be at the first control opening degree, the heating control valve to be at the heating opening degree, the electric heater to be in the working state, the four-way reversing valve to be switched to the communication direction, and the compressor to be in the working frequency.

[0012] In the preferred embodiment of the defrosting control method for the above-mentioned heat pump water heater, the step of controlling the operating state of the compressor, the electric heater, and each control valve in the control valve assembly according to the temperature of the water tank and the preset water tank temperature includes:

[0013] When the temperature of the water tank is lower than the preset water tank temperature, the current indoor ambient temperature is obtained;

[0014] The second hot water opening degree of the hot water control valve is determined based on the indoor ambient temperature.

[0015] The second control opening degree of the main control valve, the heating opening degree of the heating control valve, the heating working state of the electric heater, the connection direction of the four-way reversing valve, and the operating frequency of the compressor are determined.

[0016] The system controls the hot water control valve to the second hot water opening degree, the main control valve to the second control opening degree, the heating control valve to the heating opening degree, the electric heater to operate in the heating working state, the four-way reversing valve to switch to the communication direction, and the compressor to operate at the operating frequency.

[0017] In the preferred embodiment of the defrosting control method for the above-mentioned heat pump water heater, determining the second hot water opening degree of the hot water control valve based on the indoor ambient temperature includes:

[0018] When the indoor ambient temperature is greater than or equal to a preset upper limit temperature value, the second hot water opening degree of the hot water control valve is determined to be a first percentage.

[0019] When the indoor ambient temperature is less than or equal to a preset lower limit temperature value, the second hot water opening degree of the hot water control valve is determined to be a second percentage.

[0020] When the indoor ambient temperature is greater than the preset lower limit temperature value and less than the preset upper limit temperature value, the second hot water opening degree of the hot water control valve is determined to be the third percentage.

[0021] Wherein, the preset lower limit temperature value is less than the preset upper limit temperature, and the third percentage is greater than the second percentage and less than the first percentage.

[0022] In the preferred embodiment of the above-mentioned defrosting control method for heat pump water heaters, the method further includes:

[0023] Receive a heat recovery command, the heat recovery command being used to indicate entering heat recovery mode;

[0024] Based on the heat recovery command, the heating operation time of the hot water heat exchanger is obtained;

[0025] The frosting information of the outdoor heat exchanger is determined based on the heating operation duration;

[0026] Based on the frosting information of the outdoor heat exchanger, the heating circuit of at least one space served by the heat pump water heater is turned on, and the heating circuit is turned on to recover heat from the at least one space.

[0027] In the preferred embodiment of the above-mentioned defrosting control method for heat pump water heaters, the step of controlling the opening of the heating circuit of at least one space served by the heat pump water heater based on the frosting information of the outdoor heat exchanger includes:

[0028] When the amount of frost on the outdoor heat exchanger is less than the preset amount of frost, the heating circuit of the first space where the heat pump water heater is used is turned on and the heating circuit of the second space where the heat pump water heater is used is turned off.

[0029] When the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost, the heating circuits of all spaces served by the heat pump water heater are turned on.

[0030] In the preferred embodiment of the above-mentioned defrosting control method for heat pump water heaters, the method further includes:

[0031] When the amount of frost on the outdoor heat exchanger is less than the preset amount of frost, determine the third hot water opening of the hot water control valve, the third control opening of the main control valve, the heating opening of the heating control valve, the connection direction of the four-way reversing valve, and the operating frequency of the compressor.

[0032] The hot water control valve is controlled to be at the third hot water opening degree, the main control valve is controlled to be at the third control opening degree, the heating control valve is controlled to be at the heating opening degree, the four-way reversing valve is switched to the communication direction, and the compressor operates at the operating frequency.

[0033] In the preferred embodiment of the above-mentioned defrosting control method for heat pump water heaters, the method further includes:

[0034] When the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost, the fourth hot water opening degree of the hot water control valve, the fourth control opening degree of the main control valve, the heating opening degree of the heating control valve, the connection direction of the four-way reversing valve, and the operating frequency of the compressor are determined.

[0035] The hot water control valve is controlled to be at the fourth hot water opening degree, the main control valve is controlled to be at the fourth control opening degree, the heating control valve is controlled to be at the heating opening degree, the four-way reversing valve is switched to the communication direction, and the compressor operates at the operating frequency.

[0036] In the preferred embodiment of the above-mentioned defrosting control method for heat pump water heaters, the method further includes:

[0037] Obtain the current temperature and humidity within the first space;

[0038] Based on the current temperature and the current humidity, determine whether the heat recovery of the at least one space has been completed;

[0039] When heat recovery in at least one space is completed, the heat recovery mode is exited.

[0040] Secondly, embodiments of the present invention provide a defrosting control device for a heat pump water heater, comprising a processor integrated into the heat pump water heater. The heat pump water heater includes the processor, a water tank, and a hot water heat exchanger, an electric heater, a compressor, an indoor heat exchanger, an outdoor heat exchanger, and a control valve assembly connected to the processor. The control valve assembly includes a four-way reversing valve, a main control valve, a hot water control valve, and a heating control valve. The compressor is connected to the outdoor heat exchanger and the indoor heat exchanger respectively through the four-way reversing valve. The indoor heat exchanger is connected to the hot water heat exchanger through the heating control valve and the hot water control valve. The hot water heat exchanger is connected to the water tank for heating the water tank. The hot water heat exchanger is connected to the outdoor heat exchanger through the hot water control valve and the main control valve. The electric heater is located inside the water tank for electrically heating the water tank. The device includes:

[0041] The acquisition module is used to acquire the temperature of the water tank when a preset defrosting condition is detected.

[0042] The control module is used to control the operating status of the compressor, the electric heater, and each control valve in the control valve assembly according to the temperature of the water tank and the preset water tank temperature.

[0043] Thirdly, embodiments of the present invention provide a heat pump water heater, comprising:

[0044] The processor, memory, communication interface, water tank, and hot water heat exchanger, electric heater, compressor, indoor heat exchanger, outdoor heat exchanger, and control valve assembly connected to the processor;

[0045] The control valve assembly includes a four-way directional valve, a main control valve, a hot water control valve, and a heating control valve.

[0046] The compressor is connected to the outdoor heat exchanger and the indoor heat exchanger via the four-way reversing valve. The indoor heat exchanger is connected to the hot water heat exchanger via the heating control valve and the hot water control valve. The hot water heat exchanger is connected to the water tank for heating the water tank. The hot water heat exchanger is connected to the outdoor heat exchanger via the hot water control valve and the main control valve. The electric heater is located inside the water tank for electrically heating the water tank.

[0047] The memory is used to store the executable instructions of the processor;

[0048] The processor is the defrosting control device described in the second aspect above.

[0049] Fourthly, embodiments of the present invention provide a readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the defrosting control method for a heat pump water heater as described in any of the first aspects.

[0050] Fifthly, embodiments of the present invention provide a computer program product, including a computer program, which, when executed by a processor, is used to implement the defrosting control method for a heat pump water heater as described in any of the first aspects.

[0051] Those skilled in the art will understand that the defrosting control method, apparatus, equipment, and medium for heat pump water heaters provided in this invention determine different defrosting schemes based on the water tank temperature when the outdoor heat exchanger needs defrosting. When the water tank temperature is high, more high-temperature, high-pressure refrigerant flows to the outdoor heat exchanger for defrosting; when the water tank temperature is low, more high-temperature, high-pressure refrigerant flows to the water tank to heat the water in the tank. This scheme achieves simultaneous hot water production and defrosting by controlling the amount of refrigerant flowing to the outdoor heat exchanger and the water tank, and the energy distribution for hot water production and defrosting is highly optimized. Attached Figure Description

[0052] A preferred embodiment of the defrosting control method for a heat pump water heater according to the present invention will now be described with reference to the accompanying drawings. The drawings are as follows:

[0053] Figure 1 A schematic diagram of the structure of a heat pump water heater provided by the present invention;

[0054] Figure 2 A schematic flowchart of Embodiment 1 of the defrosting control method for a heat pump water heater provided by the present invention;

[0055] Figure 3 A schematic flowchart of Embodiment 2 of the defrosting control method for a heat pump water heater provided by the present invention;

[0056] Figure 4 A schematic flowchart of Embodiment 3 of the defrosting control method for a heat pump water heater provided by the present invention;

[0057] Figure 5 A schematic flowchart of Embodiment 4 of the defrosting control method for a heat pump water heater provided by the present invention;

[0058] Figure 6 A schematic flowchart of Embodiment 5 of the defrosting control method for a heat pump water heater provided by the present invention;

[0059] Figure 7 A schematic flowchart of Embodiment Six of the defrosting control method for a heat pump water heater provided by the present invention;

[0060] Figure 8A schematic flowchart of Embodiment 7 of the defrosting control method for a heat pump water heater provided by the present invention;

[0061] Figure 9 A schematic flowchart of Embodiment 8 of the defrosting control method for a heat pump water heater provided by the present invention;

[0062] Figure 10 A schematic flowchart of Embodiment Nine of the defrosting control method for a heat pump water heater provided by the present invention;

[0063] Figure 11 A schematic diagram of the structure of a first embodiment of the defrosting control device for a heat pump water heater provided by the present invention;

[0064] Figure 12 A schematic diagram of the structure of a second embodiment of the defrosting control device for a heat pump water heater provided by the present invention;

[0065] Figure 13 A schematic diagram of the structure of the heat pump water heater provided by the present invention. Detailed Implementation

[0066] First, those skilled in the art should understand that these embodiments are merely for explaining the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0067] Secondly, it should be noted that in the description of the embodiments of the present invention, the terms "inner" and "outer", etc., which indicate the direction or positional relationship, are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention.

[0068] Furthermore, it should be noted that, in the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.

[0069] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0070] With the development of technology, water heaters have met people's needs for hot water, and air conditioners have met their needs for heating and cooling. However, neither hot water production equipment nor heating and cooling equipment operates at full capacity 24 hours a day, which leads to low space utilization and equipment utilization.

[0071] To address this, researchers have proposed a novel air-source heat pump water heater. This new air-source heat pump water heater can serve multiple purposes, simultaneously meeting users' needs for heating, cooling, and hot water. Compared to traditional air-source heat pump water heaters and cooling / heating equipment, this not only improves equipment utilization and energy efficiency but also reduces the installation space required indoors, thus significantly increasing space utilization.

[0072] However, when the new air source heat pump water heater is running in winter, the outdoor heat exchanger will usually frost up, which requires defrosting. The method of defrosting the new air source heat pump water heater during the hot water production process still needs to be studied.

[0073] This embodiment provides a defrosting control method for a heat pump water heater. When defrosting the outdoor heat exchanger is required, the water tank temperature is fully considered. When the water tank temperature is high, more of the high-temperature, high-pressure refrigerant generated by the compressor flows to the outdoor heat exchanger for defrosting, and a small amount flows to the water tank to heat the water. When the water tank temperature is low, more refrigerant flows to the water tank to heat the water, and a small amount flows to the outdoor heat exchanger for defrosting. This method achieves defrosting while maintaining a high water tank temperature, meeting user needs.

[0074] The principles and features of the embodiments of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the embodiments of the present invention and are not intended to limit the scope of the embodiments of the present invention.

[0075] Figure 1 A schematic diagram of the structure of the heat pump water heater provided by the present invention is shown below. Figure 1As shown, this embodiment of the invention provides a heat pump water heater, which can also be called an air source heat pump water heater. A heat pump water heater may include: a processor 100, a water tank 103, and a hot water heat exchanger 102, an electric heater 104, a compressor 101, an indoor heat exchanger 109, an outdoor heat exchanger 111, and a control valve assembly connected to the processor; the control valve assembly includes a four-way reversing valve 110, a main control valve 113, a hot water control valve 107, and a heating control valve 108; the compressor 101 is connected to the outdoor heat exchanger 111 and the indoor heat exchanger 109 respectively through the four-way reversing valve 110; the indoor heat exchanger 109 is connected to the hot water heat exchanger 102 through the heating control valve 108 and the hot water control valve 107; the hot water heat exchanger 102 is connected to the water tank 103 for heating the water in the water tank 103; the hot water heat exchanger 103 is connected to the outdoor heat exchanger 111 through the hot water control valve 107 and the main control valve 113; and the electric heater 104 is located inside the water tank 103 for electrically heating the water in the water tank 103.

[0076] When hot water is produced and defrosted simultaneously, the heat pump water heater has two circuits to achieve hot water production and defrosting respectively. For the hot water production circuit, high-temperature and high-pressure refrigerant is output from the compressor 101, passes through the three-way port to the hot water heat exchanger 102, and heats the water in the water tank 103. The refrigerant then passes from the hot water heat exchanger 102 through the hot water control valve 107, the three-way port and the heating control valve 108 to the indoor heat exchanger 109 for heat exchange. The refrigerant then flows back from the indoor heat exchanger 109 through the four-way reversing valve 110 to the compressor 110. For the defrosting circuit, high-temperature and high-pressure refrigerant is output from the compressor 101, passes through the four-way reversing valve 110 to reach the outdoor heat exchanger 111 for heat exchange and defrosting. The refrigerant then passes from the outdoor heat exchanger 111 through the main control valve 113 and the three-way port to merge with the refrigerant in the hot water circuit, passes through the heating control valve 108 to reach the indoor heat exchanger 109, and then flows back from the indoor heat exchanger 109 through the four-way reversing valve 110 to the compressor 110.

[0077] It should be noted that, from Figure 1 As can be seen, the heat pump water heater may also include an economizer, and the control valve assembly may include an auxiliary control valve 114. The economizer is connected between the main control valve 113 and the compressor 101, and the auxiliary control valve 114 is connected between the main control valve 113 and the economizer. Specifically, the roles of the economizer and the auxiliary control valve 114 in the heat pump water heater can be referred to the description in related technologies, and will not be further elaborated in this embodiment.

[0078] The heat pump water heater provided in this embodiment can achieve defrosting while producing hot water through a hot water production circuit and a defrosting circuit. In addition, the energy distribution for hot water production and defrosting can be optimized by controlling the opening of the main control valve and the heating valve.

[0079] The technical solution of this application will now be described in detail with reference to the accompanying drawings and the structure of the heat pump water heater, through specific embodiments. It should be noted that the following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0080] Figure 2 A schematic flowchart of Embodiment 1 of the defrosting control method for a heat pump water heater provided by the present invention is shown below. Figure 2 As shown, the defrosting control method for this heat pump water heater specifically includes the following steps:

[0081] S201: When the preset defrosting conditions are met, the temperature of the water tank is obtained.

[0082] When operating a heat pump water heater at low temperatures, the outdoor heat exchanger may frost up, affecting the operation of the heat pump water heater, so defrosting is necessary.

[0083] In this step, when the preset defrosting conditions are detected, the temperature of the water tank 103 is obtained so that the defrosting scheme can be determined based on the temperature of the water tank 103.

[0084] It should be noted that the method for detecting whether a heat pump water heater meets the preset defrost conditions can be: the heat pump water heater performs timed defrost, and the preset defrost conditions are met when the time reaches a certain duration. Another method is: the heat pump water heater detects the outdoor ambient temperature, and the preset defrost conditions are met when the outdoor ambient temperature is lower than a preset ambient temperature, such as -5 degrees Celsius, -8 degrees Celsius, or -10 degrees Celsius. Yet another method is: the preset defrost conditions are met when the compressor 101 operates in heating mode for a preset first duration, such as 30 minutes, 1 hour, or 2 hours. This embodiment of the invention does not specifically limit the method for detecting whether the heat pump water heater meets the preset defrost conditions, nor does it specifically limit the preset ambient temperature or the preset first duration; these can be selected and set according to actual conditions.

[0085] It should be noted that a first temperature sensor 105 may be installed on the upper part of the water tank 103 of the heat pump water heater, and a second temperature sensor 106 may be installed on the lower part of the water tank 103. The first temperature sensor 105 and the second temperature sensor 106 are used to detect the temperature of the water tank. The heat pump water heater can obtain the water tank temperature by using only the first temperature sensor 105; it can also obtain the two temperatures using the first temperature sensor 105 and the second temperature sensor 106, and then calculate the average value as the water tank temperature; or it can obtain the water tank temperature using only the second temperature sensor 106. This embodiment of the invention does not limit the method by which the heat pump water heater obtains the water tank temperature, and can be selected according to the actual situation.

[0086] S202: Control the operating status of each control valve in the compressor, electric heater and control valve assembly according to the temperature of the water tank and the preset water tank temperature.

[0087] In this step, after the heat pump water heater obtains the temperature of the water tank 103, it controls the operating status of the compressor 101, the electric heater 104, and each control valve in the control valve assembly based on the temperature of the water tank 103 and the preset water tank temperature. When the temperature of the water tank 103 is higher than the preset water tank temperature, it means that relatively less energy can be used for hot water production, and more energy can be used for defrosting. This can be achieved by controlling the main control valve 113 in the control valve assembly to be at a larger opening and the hot water control valve 107 to be at a smaller opening. When the temperature of the water tank 103 is less than or equal to the preset water tank temperature, it means that relatively more energy can be used for hot water production, and less energy can be used for defrosting. This can be achieved by controlling the main control valve 113 in the control valve assembly to be at a smaller opening and the hot water control valve 107 to be at a larger opening.

[0088] It should be noted that the preset water tank temperature is set by staff or the user in the heat pump water heater before the implementation of this solution, to determine its relationship with the water tank temperature. The preset water tank temperature can be 40 degrees Celsius, 45 degrees Celsius, or even 50 degrees Celsius. This embodiment of the invention does not specifically limit the preset water tank temperature, and it can be set according to the actual situation.

[0089] It should be noted that when the heat pump water heater detects that defrosting is complete, it exits the defrosting process and restores the working state of the compressor 101, electric heater 104, and each control valve in the control valve assembly to the working state before defrosting.

[0090] It should be noted that the defrosting completion detection method for a heat pump water heater can be as follows: The temperature of the outdoor heat exchanger is detected, and defrosting is considered complete when the outdoor heat exchanger temperature reaches a preset defrosting completion temperature; this preset defrosting completion temperature can be 10 degrees Celsius, 15 degrees Celsius, or even 20 degrees Celsius. Alternatively, the defrosting completion detection method can be based on the compressor's operating time during the defrosting process; defrosting is considered complete when the operating time reaches a preset second duration; this preset second duration can be 8 minutes, 10 minutes, or even 15 minutes. This embodiment of the invention does not limit the method for detecting defrosting completion in the heat pump water heater, nor does it specifically limit the preset defrosting completion temperature or the preset second duration; these can be selected and set according to actual conditions.

[0091] The defrosting control method for heat pump water heaters provided in this embodiment determines the defrosting scheme based on the obtained water tank temperature when defrosting is required. When the water tank temperature is higher, more energy is used for defrosting; when the water tank temperature is lower, more energy is used for hot water production. This allows for simultaneous hot water production and defrosting, with a high degree of energy allocation optimization.

[0092] Figure 3 A schematic flowchart of Embodiment 2 of the defrosting control method for a heat pump water heater provided by the present invention is shown below. Figure 3 As shown, based on the above embodiments, step S202 in Embodiment 1 can be implemented through the following steps:

[0093] S301: When the water tank temperature is greater than or equal to the preset water tank temperature, determine the first hot water opening degree of the hot water control valve, the first control opening degree of the main control valve, the heating opening degree of the heating control valve, the working status of the electric heater, the connection direction of the four-way reversing valve, and the working frequency of the compressor.

[0094] In this step, after the heat pump water heater obtains the temperature of the water tank 103, it compares it with the preset water tank temperature. When the temperature of the water tank 103 is greater than or equal to the preset water tank temperature, the following settings are determined: the opening degree of the hot water control valve 107 is the first hot water opening degree; the opening degree of the main control valve 113 is the first control opening degree; the opening degree of the heating control valve 108 is the heating opening degree; the operating state of the electric heater 104 is determined; the connection direction of the four-way reversing valve 110 is determined; and the operating frequency of the compressor 101 is determined. The connection direction of the four-way reversing valve 104 is as follows: port a is connected to port c, allowing the compressor 101 to connect to the outdoor heat exchanger 111 through the four-way reversing valve 110; port b is connected to port d, allowing the indoor heat exchanger 109 to connect to the compressor through the four-way reversing valve 110.

[0095] It should be noted that the first hot water opening degree can be 10%, 15%, or even 20%. The first control opening degree can be 70%, 80%, or even 90%. The heating opening degree can be 80%, 90%, or even 100%. The operating frequency of the compressor 101 can be 50Hz, 60Hz, or even 70Hz. This embodiment of the invention does not limit the first hot water opening degree, the first control opening degree, the heating opening degree, or the operating frequency of the compressor 101; these can be set according to actual conditions.

[0096] It should be noted that the operating state of the electric heater 104 can be either a heating state or a non-heating state. The operating state of the electric heater 104 can be determined by: the operator pre-setting this operating state in the heat pump water heater, which can then directly determine it. Alternatively, the operating state of the electric heater 104 can be determined by: defining the operating state of the electric heater 104 before defrosting as the operating state of the electric heater 104. It should be noted that this embodiment of the invention does not limit the method of determining the operating state of the electric heater 104; it can be selected according to the actual situation.

[0097] S302: Controls the hot water control valve to the first hot water opening, the main control valve to the first control opening, the heating control valve to the heating opening, the electric heater to the working state, the four-way reversing valve to the connecting direction, and the compressor to the working frequency.

[0098] In this step, the heat pump water heater determines the opening degree of the hot water control valve 107, the main control valve 113, the heating control valve 108, the working state of the electric heater 104, the connection direction of the four-way reversing valve 110, and the working frequency of the compressor 101. Then, it controls the hot water control valve 107 to the first hot water opening degree, the main control valve 113 to the first control opening degree, the heating control valve 108 to the heating opening degree, the electric heater 104 to the working state, the four-way reversing valve 110 to the connection direction, and the compressor 101 to the working frequency.

[0099] It should be noted that the heat pump water heater can also control the auxiliary control valve 114 to close and control the fan 112 to close.

[0100] Specifically, when the hot water control valve 107 is at a smaller first hot water opening degree and the main control valve 113 is at a larger first control opening degree, for hot water production, high-temperature and high-pressure refrigerant is output from the compressor 101, flowing sequentially through the three-way port, hot water heat exchanger 102, hot water valve 107, heating valve 108, indoor heat exchanger 109, port b of the four-way reversing valve 110, and port d of the four-way reversing valve 110, before returning to the compressor 101. For defrosting, high-temperature and high-pressure refrigerant is output from the compressor 101, flowing sequentially through the three-way port, port a of the four-way reversing valve 110, port c of the four-way reversing valve 110, outdoor heat exchanger 111, main control valve 113, heating valve 108, indoor heat exchanger 109, port b of the four-way reversing valve 110, and port d of the four-way reversing valve 110, before returning to the compressor 101. The amount of refrigerant flowing through the hot water production circuit is relatively small, while the amount flowing through the defrosting circuit is relatively large.

[0101] The defrosting control method for heat pump water heaters provided in this embodiment controls the hot water control valve to a smaller opening and the main control valve to a larger opening when the water tank temperature is greater than or equal to a preset water tank temperature. This results in more energy being used for defrosting and less energy being used for hot water production. This solution can both produce hot water and defrost, while ensuring that the water temperature in the tank is relatively high and improving defrosting efficiency. The energy distribution for hot water production and defrosting is more reasonable.

[0102] Figure 4 A schematic flowchart of Embodiment 3 of the defrosting control method for a heat pump water heater provided by the present invention is shown below. Figure 4 As shown, based on the above embodiments, step S202 in Embodiment 1 can be implemented through the following steps:

[0103] S401: Obtain the current indoor ambient temperature when the water tank temperature is lower than the preset water tank temperature.

[0104] In this step, after the heat pump water heater obtains the temperature of the water tank 103, it compares it with the preset water tank temperature. If the temperature of the water tank 103 is lower than the preset water tank temperature, it means that the temperature of the water in the water tank 103 is low. In order to meet the user's hot water needs, more energy needs to be used to produce hot water. This requires obtaining the current indoor ambient temperature so that the energy used for producing hot water can be allocated according to the ambient temperature.

[0105] S402: Determine the second hot water opening degree of the hot water control valve based on the indoor ambient temperature.

[0106] In this step, after the heat pump water heater obtains the indoor ambient temperature, in order to provide a better user experience, the higher the indoor ambient temperature, the faster the hot water needs to be produced. Therefore, the second hot water opening of the hot water control valve needs to be determined according to the indoor ambient temperature.

[0107] It should be noted that when the temperature of water tank 103 is lower than the preset water tank temperature, more energy is needed to produce hot water compared to when the temperature of water tank 103 is greater than or equal to the preset water tank temperature. Therefore, the first hot water opening degree in Embodiment 2 is required to be less than the second hot water opening degree. The second hot water opening degree can be 30%, 50%, or 90%. This embodiment of the invention does not specifically limit the second hot water opening degree, and it can be selected according to the actual situation.

[0108] S403: Determine the second control opening of the main control valve, the heating opening of the heating control valve, the heating operation status of the electric heater, the connection direction of the four-way reversing valve, and the operating frequency of the compressor.

[0109] In this step, when the heat pump water heater determines that the temperature of the water tank 103 is lower than the preset water tank temperature, it also determines the opening degree of the main control valve 113 to the second control opening degree, the opening degree of the heating control valve 108 to the heating opening degree, the heating working state of the electric heater 104, the connection direction of the four-way reversing valve 110, and the operating frequency of the compressor 101. The connection direction of the four-way reversing valve 104 is as follows: port a is connected to port c, which allows the compressor 101 to connect to the outdoor heat exchanger 111 through the four-way reversing valve 110; port b is connected to port d, which allows the indoor heat exchanger 109 to connect to the compressor through the four-way reversing valve 110. In order to quickly produce hot water, the electric heater 104 is in the heating working state.

[0110] It should be noted that the heating setting can be 80%, 90%, or even 100%. The operating frequency of the compressor 101 can be 50Hz, 60Hz, or even 70Hz. This embodiment of the invention does not limit the heating setting or the operating frequency of the compressor 101; they can be set according to actual conditions.

[0111] It should be noted that when the temperature of water tank 103 is lower than the preset water tank temperature, less energy is needed for defrosting compared to when the temperature of water tank 103 is greater than or equal to the preset water tank temperature. Therefore, the first control opening degree in Embodiment 2 is required to be greater than the second control opening degree. The second control opening degree can be 30%, 40%, or 50%. This embodiment of the invention does not specifically limit the second control opening degree, and it can be selected according to the actual situation.

[0112] It should be noted that the execution order of the steps from obtaining the indoor ambient temperature to determining the second hot water opening degree and step S403 can be as follows: first, the step from obtaining the indoor ambient temperature to determining the second hot water opening degree is executed, and then step S403 is executed; second, step S403 is executed first, and then the step from obtaining the indoor ambient temperature to determining the second hot water opening degree is executed; third, the steps from obtaining the indoor ambient temperature to determining the second hot water opening degree and step S403 are executed simultaneously. This embodiment of the invention does not limit the execution order of the steps from obtaining the indoor ambient temperature to determining the second hot water opening degree and step S403, and it can be determined according to the actual situation.

[0113] S404: Controls the hot water control valve to the second hot water opening position, the main control valve to the second control opening position, the heating control valve to the heating opening position, the electric heater to the heating working state, the four-way reversing valve to the connecting direction, and the compressor to the working frequency.

[0114] In this step, the heat pump water heater determines the opening degree of the hot water control valve 107, the main control valve 113, the heating control valve 108, the working state of the electric heater 104, the connection direction of the four-way reversing valve 110, and the working frequency of the compressor 101. Then, it controls the hot water control valve 107 to the second hot water opening degree, the main control valve 113 to the second control opening degree, the heating control valve 108 to the heating opening degree, the electric heater 104 to the working state, the four-way reversing valve 110 to the connection direction, and the compressor 101 to the working frequency.

[0115] It should be noted that the heat pump water heater can also control the auxiliary control valve 114 to close and control the fan 112 to close.

[0116] Specifically, when the hot water control valve 107 is at a larger second hot water opening degree and the main control valve 113 is at a smaller second control opening degree, for hot water production, high-temperature and high-pressure refrigerant is output from the compressor 101, flowing sequentially through the three-way port, hot water heat exchanger 102, hot water valve 107, heating valve 108, indoor heat exchanger 109, port b of the four-way reversing valve 110, and port d of the four-way reversing valve 110, before returning to the compressor 101. For defrosting, high-temperature and high-pressure refrigerant is output from the compressor 101, flowing sequentially through the three-way port, port a of the four-way reversing valve 110, port c of the four-way reversing valve 110, outdoor heat exchanger 111, main control valve 113, heating valve 108, indoor heat exchanger 109, port b of the four-way reversing valve 110, and port d of the four-way reversing valve 110, before returning to the compressor 101. The amount of refrigerant flowing through the hot water production circuit is relatively larger, while the amount flowing through the defrosting circuit is relatively smaller.

[0117] The defrosting control method for heat pump water heaters provided in this embodiment determines the opening degree of the hot water control valve based on the indoor ambient temperature when the water tank temperature is lower than the preset water tank temperature. This opening degree is relatively small, while the main control valve is at a larger opening, resulting in less energy being used for defrosting and more energy being used for hot water production. This solution can both produce hot water and defrost, while ensuring that the water temperature in the tank remains relatively high, resulting in a more rational energy distribution between hot water production and defrosting.

[0118] Figure 5 A schematic flowchart of Embodiment 4 of the defrosting control method for a heat pump water heater provided by the present invention is shown below. Figure 5 As shown, based on the above embodiments, step S402 in Embodiment 3 can be implemented through the following steps:

[0119] S501: When the indoor ambient temperature is greater than or equal to the preset upper limit temperature value, the second hot water opening degree of the hot water control valve is determined to be the first percentage.

[0120] In this step, after the heat pump water heater obtains the current indoor ambient temperature, when the indoor ambient temperature is greater than or equal to the preset upper limit temperature value, it determines the second hot water opening degree of the hot water control valve 107 to be the first percentage.

[0121] It should be noted that the preset upper limit temperature value and the first percentage are set by the staff or user in the heat pump water heater before the implementation of this solution, and are used to determine the second hot water opening degree. The preset upper limit temperature value can be 23 degrees Celsius, 25 degrees Celsius, or 28 degrees Celsius. The first percentage can be 60%, 65%, or 70%. This embodiment of the invention does not specifically limit the preset upper limit temperature value and the first percentage, and can be set according to the actual situation.

[0122] S502: When the indoor ambient temperature is less than or equal to the preset lower limit temperature value, the second hot water opening degree of the hot water control valve is determined to be the second percentage.

[0123] In this step, after the heat pump water heater obtains the current indoor ambient temperature, when the indoor ambient temperature is less than or equal to the preset lower limit temperature value, it determines the second hot water opening degree of the hot water control valve 107 to be the second percentage.

[0124] It should be noted that the preset lower limit temperature value and the second percentage are set by the staff or user in the heat pump water heater before the implementation of this solution, and are used to determine the second hot water opening degree. The preset upper limit temperature value can be 17 degrees Celsius, 20 degrees Celsius, or 22 degrees Celsius. The second percentage can be 45%, 50%, or 55%. This embodiment of the invention does not specifically limit the preset lower limit temperature value and the second percentage, and can be set according to the actual situation.

[0125] S503: When the indoor environmental temperature is greater than the preset lower limit temperature value and less than the preset upper limit temperature, determine that the second hot water opening degree of the hot water control valve is the third percentage.

[0126] In this step, after the heat pump water heater obtains the current indoor environmental temperature, when the indoor environmental temperature is greater than the preset lower limit temperature value and less than the preset upper limit temperature, determine that the second hot water opening degree of the hot water control valve 107 is the third percentage.

[0127] It should be noted that the third percentage is set in the heat pump water heater by the staff or user before the implementation of this solution and is used to determine the second hot water opening degree. The third percentage can be 30%, 35%, or 40%. The embodiments of the present invention do not specifically limit the third percentage, and it can be set according to the actual situation.

[0128] It should be noted that the preset lower limit temperature value is less than the preset upper limit temperature, and the third percentage is greater than the second percentage and less than the first percentage.

[0129] Exemplarily, the relationship between the indoor environmental temperature and the second hot water opening degree is shown in Table 1:

[0130] Table 1

[0131] Indoor ambient temperature Second hot water opening T≥25℃ 65％ 20℃<T<25℃ 50％ T≤20℃ 35％

[0132] As shown in Table 1, T represents the indoor environmental temperature, the preset upper limit temperature value is 25°C, and the preset lower limit temperature value is 20°C. When T≥25°C, the second hot water opening degree is 65%; when 20°C < T < 25°C, the second hot water opening degree is 50%; when T≤20°C, the second hot water opening degree is 35%;

[0133] It should be noted that Table 1 is only an example of the relationship between the indoor environmental temperature and the second hot water opening degree, and does not limit the indoor environmental temperature, the second hot water opening degree, the preset upper limit temperature value, and the preset lower limit temperature value therein, which can be determined and set according to the actual situation.

[0134] It should be noted that the numbers of steps S501, S502, and S503 are not the execution order of the three steps, but which step to execute is determined according to the relationship between the indoor environmental temperature and the preset upper limit temperature value and the preset lower limit temperature value.

[0135] The defrosting control method of the heat pump water heater provided in this embodiment effectively improves the accuracy of determining the second hot water opening degree by determining the second hot water opening degree of the hot water control valve according to the relationship between the indoor environmental temperature and the preset upper limit temperature value and the preset lower limit temperature value.

[0136] Figure 6A schematic flowchart of Embodiment 5 of the defrosting control method for a heat pump water heater provided by the present invention is shown below. Figure 6 As shown, the defrosting control method for this heat pump water heater also includes the following steps:

[0137] S601: Receives heat recovery commands.

[0138] After showering or cooking, when the temperature in the bathroom or kitchen is high, users can activate the heat recovery mode, and the recovered energy can be used to produce hot water and defrost.

[0139] In this step, the user activates the heat recovery mode, and the heat pump water heater receives the heat recovery command, which is used to indicate that the heat recovery mode should be entered.

[0140] It should be noted that users can activate the heat recovery mode in several ways: First, through voice control, where the user speaks a heat recovery command, which the heat pump water heater receives. Second, the user can directly operate the heat pump water heater, such as clicking a corresponding button, which the heat pump water heater then receives. Third, the user can send the heat recovery command to a server via a terminal device, and the server then forwards the command to the heat pump water heater, which receives the command. This embodiment of the invention does not limit the method by which the user activates the heat recovery mode; the method can be chosen according to the actual situation.

[0141] S602: Obtain the heating operation time of the hot water heat exchanger based on the heat recovery command.

[0142] S603: Determine the frosting information of the outdoor heat exchanger based on the heating operation duration.

[0143] In the above steps, after receiving the heat recovery command, the heat pump water heater needs to obtain the heating operation time of the hot water heat exchanger 102 (which is also the heating operation time of the compressor 101) based on the heat recovery command in order to determine which heating circuits in which spaces to activate. Then, based on the heating operation time, it determines the frosting information of the outdoor heat exchanger 111. This frosting information is used to subsequently determine which heating circuits in which spaces to activate. The frosting information indicates the amount of frost on the outdoor heat exchanger 111.

[0144] For example, if the heating operation duration is greater than or equal to a preset third duration, such as 50 minutes, then the amount of frost on the outdoor heat exchanger 111 is determined to be greater than or equal to a preset frost amount; if the heating operation duration is less than the preset third duration, then the amount of frost on the outdoor heat exchanger 111 is determined to be less than the preset frost amount. The preset third duration can also be 40 minutes or 1 hour. This embodiment of the invention does not limit the preset third duration and can be set according to actual conditions.

[0145] Optionally, the frosting information of the outdoor heat exchanger 111 can also be determined by installing an infrared sensor on the outdoor heat exchanger 111 to directly obtain the frosting thickness on the outdoor heat exchanger 111. If the frosting thickness is greater than or equal to a preset thickness, for example, a preset thickness of 5 mm, then the frosting amount of the outdoor heat exchanger 111 is determined to be greater than or equal to the preset frosting amount; if the frosting thickness is less than the preset thickness, then the frosting amount of the outdoor heat exchanger 111 is determined to be less than the preset frosting amount. The preset thickness can also be 6 mm or 8 mm. This application embodiment does not specifically limit the preset thickness and can set it according to the actual situation.

[0146] Optionally, the frosting information of the outdoor heat exchanger 111 can also be determined by: determining the frosting information of the outdoor heat exchanger 111 based on its temperature. If the temperature of the outdoor heat exchanger 111 is less than or equal to a preset frosting temperature, for example, a frosting temperature of -5 degrees Celsius, then the frosting amount of the outdoor heat exchanger 111 is determined to be greater than or equal to the preset frosting amount; if the temperature of the outdoor heat exchanger 111 is greater than the preset frosting temperature, then the frosting amount of the outdoor heat exchanger 111 is determined to be less than the preset frosting amount. The preset frosting temperature can also be 0 degrees Celsius or 5 degrees Celsius. This embodiment of the invention does not specifically limit the preset frosting temperature; it can be set according to actual conditions.

[0147] It should be noted that the embodiments of the present invention do not limit the method of determining the frosting information of the outdoor heat exchanger 111, and can be selected according to the actual situation.

[0148] S604: Based on the frosting information of the outdoor heat exchanger, control the opening of the heating circuit of at least one space served by the heat pump water heater.

[0149] In this step, after determining the frosting status of the outdoor heat exchanger 111, the heat pump water heater controls the opening of the heating circuit for at least one space served by the heat pump water heater based on the frosting information of the outdoor heat exchanger. The opening of the heating circuit is used to recover heat from at least one space. When the frosting amount 111 of the outdoor heat exchanger is less than the preset frosting amount, it indicates that less energy is required for defrosting, and the heating circuit for fewer spaces can be opened. When the frosting amount 111 of the outdoor heat exchanger is greater than or equal to the preset frosting amount, it indicates that more energy is required for defrosting, and the heating circuit for more spaces can be opened.

[0150] The defrosting control method for heat pump water heaters provided in this embodiment involves the heat pump water heater determining to activate the heating circuit of at least one space based on the frost information of the outdoor heat exchanger after receiving a heat recovery command. This enables heat recovery and reduces energy waste.

[0151] Figure 7 A schematic flowchart of Embodiment Six of the defrosting control method for a heat pump water heater provided by the present invention is shown below. Figure 7As shown, based on the above embodiments, step S604 in Embodiment 5 can be implemented through the following steps:

[0152] S701: When the amount of frost on the outdoor heat exchanger is less than the preset amount of frost, the heating circuit of the first space served by the heat pump water heater is opened and the heating circuit of the second space served by the heat pump water heater is closed.

[0153] In this step, after the heat pump water heater determines the frost information of the outdoor heat exchanger 111, when the frost amount of the outdoor heat exchanger 111 is less than the preset frost amount, it controls the heating circuit of the first space where the heat pump water heater is used to open and the heating circuit of the second space where the heat pump water heater is used to close.

[0154] Specifically, a temperature sensor can be installed in each space served by the heat pump water heater, and each temperature sensor is connected to the processor of the heat pump water heater. When the amount of frost on the outdoor heat exchanger 111 is less than the preset amount of frost, it indicates that less energy is required for defrosting, and the heating circuit of at least one space can be turned on. The first space can be determined by the temperature of each space, sorted from high to low, with the space with the highest temperature designated as the first space, or the spaces corresponding to the first three temperatures designated as the first space. All spaces served by the heat pump water heater except the first space are designated as the second space. This embodiment of the invention does not limit the number of spaces included in the first space, and can be set according to actual conditions.

[0155] Optionally, the first and second spaces served by the heat pump water heater can be determined as follows: After the heat pump water heater is installed, the user can set which spaces' heating circuits are activated, and the heat pump water heater can then designate these spaces as the first spaces. The spaces other than the first spaces among all the spaces served by the heat pump water heater are designated as the second spaces.

[0156] It should be noted that the embodiments of the present invention do not limit the method of determining the first space and the second space where the heat pump water heater is applied, and can be selected according to the actual situation.

[0157] S702: When the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost, control the opening of the heating circuits in all spaces served by the heat pump water heater.

[0158] In this step, after the heat pump water heater determines the frost information of the outdoor heat exchanger 111, when the amount of frost on the outdoor heat exchanger is greater than or equal to the preset frost amount, it controls the energy required for defrosting to be greater, and determines that the heating circuit of all spaces served by the heat pump water heater is turned on.

[0159] Optionally, when the frost amount 111 of the outdoor heat exchanger is greater than or equal to the preset frost amount, after the heat pump water heater is installed, the user can set which space heating circuits to activate, so that the heat pump water heater can directly determine which space heating circuits to activate.

[0160] It should be noted that the numbers S701 and S702 do not indicate the execution order of the two steps, but rather determine which step to execute based on the relationship between the amount of frost on the outdoor heat exchanger and the preset amount of frost.

[0161] The defrosting control method for heat pump water heaters provided in this embodiment determines which heating circuits to activate based on the relationship between the amount of frost on the outdoor heat exchanger and the preset amount of frost, effectively improving the accuracy of energy recovery.

[0162] Figure 8 A schematic flowchart of Embodiment Seven of the defrosting control method for a heat pump water heater provided by the present invention is shown below. Figure 8 As shown, based on the above embodiments five and six, the defrosting control method for this heat pump water heater further includes the following steps:

[0163] S801: When the amount of frost on the outdoor heat exchanger is less than the preset amount of frost, determine the third hot water opening of the hot water control valve, the third control opening of the main control valve, the heating opening of the heating control valve, the connection direction of the four-way reversing valve, and the operating frequency of the compressor.

[0164] In this step, after the heat pump water heater determines the frosting information of the outdoor heat exchanger 111, when the amount of frosting on the outdoor heat exchanger 111 is less than the preset amount of frosting, it determines the opening degree of the hot water control valve 107 to the third hot water opening degree, the opening degree of the main control valve 113 to the third control opening degree, the opening degree of the heating control valve 108 to the heating opening degree, the connection direction of the four-way reversing valve 110, and the operating frequency of the compressor 101. The connection direction of the four-way reversing valve 104 is as follows: port a is connected to port c, which allows the compressor 101 to connect to the outdoor heat exchanger 111 through the four-way reversing valve 110; port b is connected to port d, which allows the indoor heat exchanger 109 to connect to the compressor through the four-way reversing valve 110.

[0165] It should be noted that the third hot water opening degree can be 70%, 90%, or even 100%. The third control opening degree can be 10%, 20%, or even 30%. The heating opening degree can be 80%, 90%, or even 100%. The operating frequency of the compressor 101 can be 50Hz, 60Hz, or even 70Hz. This embodiment of the invention does not limit the third hot water opening degree, the third control opening degree, the heating opening degree, or the operating frequency of the compressor 101; these can be set according to actual conditions.

[0166] S802: Controls the hot water control valve to the third hot water opening position, the main control valve to the third control opening position, the heating control valve to the heating opening position, the four-way reversing valve to switch to the connecting direction, and the compressor to operate at the operating frequency.

[0167] In this step, after the heat pump water heater determines the opening degree of the hot water control valve 107, the main control valve 113, and the heating control valve 108, the connection direction of the four-way reversing valve 110, and the operating frequency of the compressor 101, it controls the hot water control valve 107 to the third hot water opening degree, the main control valve 113 to the third control opening degree, the heating control valve 108 to the heating opening degree, the four-way reversing valve 110 to the connection direction, and the compressor 101 to operate at the operating frequency.

[0168] It should be noted that the heat pump water heater can also control the auxiliary control valve 114 to close and control the fan 112 to close.

[0169] Specifically, when the hot water control valve 107 is at a larger third hot water opening and the main control valve 113 is at a smaller third control opening, for hot water production, high-temperature and high-pressure refrigerant is output from compressor 101, flowing sequentially through the three-way port, hot water heat exchanger 102, hot water valve 107, heating valve 108, indoor heat exchanger 109, port b of four-way reversing valve 110, and port d of four-way reversing valve 110, before returning to compressor 101. For defrosting, high-temperature and high-pressure refrigerant is output from compressor 101, flowing sequentially through the three-way port, port a of four-way reversing valve 110, port c of four-way reversing valve 110, outdoor heat exchanger 111, main control valve 113, heating valve 108, indoor heat exchanger 109, port b of four-way reversing valve 110, and port d of four-way reversing valve 110, before returning to compressor 101. The amount of refrigerant flowing through the hot water production circuit is relatively larger, while the amount flowing through the defrosting circuit is relatively smaller.

[0170] The defrosting control method for heat pump water heaters provided in this embodiment controls the hot water control valve to a larger opening and the main control valve to a smaller opening when the amount of frost on the outdoor heat exchanger is less than the preset amount of frost. This allows the energy recovered from heat to be used for defrosting and hot water production, and the energy distribution is more reasonable.

[0171] Figure 9 A schematic flowchart of Embodiment 8 of the defrosting control method for a heat pump water heater provided by the present invention is shown below. Figure 9 As shown, based on the above embodiments five and six, the defrosting control method for this heat pump water heater further includes the following steps:

[0172] S901: When the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost, determine the fourth hot water opening of the hot water control valve, the fourth control opening of the main control valve, the heating opening of the heating control valve, the connection direction of the four-way reversing valve, and the operating frequency of the compressor.

[0173] In this step, after the heat pump water heater determines the frosting information of the outdoor heat exchanger 111, when the frosting amount of the outdoor heat exchanger 111 is greater than or equal to the preset frosting amount, it determines the opening degree of the hot water control valve 107 to be the fourth hot water opening degree, the opening degree of the main control valve 113 to be the fourth control opening degree, the opening degree of the heating control valve 108 to be the heating opening degree, the connection direction of the four-way reversing valve 110, and the operating frequency of the compressor 101. The connection direction of the four-way reversing valve 104 is as follows: port a is connected to port c, which allows the compressor 101 to be connected to the outdoor heat exchanger 111 through the four-way reversing valve 110; port b is connected to port d, which allows the indoor heat exchanger 109 to be connected to the compressor through the four-way reversing valve 110.

[0174] It should be noted that the heating setting can be 80%, 90%, or even 100%. The operating frequency of the compressor 101 can be 50Hz, 60Hz, or even 70Hz. This embodiment of the invention does not limit the heating setting or the operating frequency of the compressor 101; they can be set according to actual conditions.

[0175] It should be noted that when the frost amount on the outdoor heat exchanger 111 is greater than or equal to the preset frost amount, more energy is required for defrosting compared to when the frost amount on the outdoor heat exchanger 111 is less than the preset frost amount. Therefore, in Embodiment Seven, the third hot water opening degree must be greater than the fourth hot water opening degree, and the third control opening degree must be less than the fourth control opening degree. The fourth hot water opening degree can be 10%, 20%, or 30%. The fourth control opening degree can be 70%, 80%, or 90%. This embodiment of the invention does not limit the fourth control opening degree or the fourth hot water opening degree; they can be set according to actual conditions.

[0176] S902: Controls the hot water control valve to the fourth hot water opening position, the main control valve to the fourth control opening position, the heating control valve to the heating opening position, the four-way reversing valve to switch to the connecting direction, and the compressor to operate at the operating frequency.

[0177] In this step, after the heat pump water heater determines the opening degree of the hot water control valve 107, the main control valve 113, and the heating control valve 108, the connection direction of the four-way reversing valve 110, and the operating frequency of the compressor 101, it controls the hot water control valve 107 to the fourth hot water opening degree, the main control valve 113 to the fourth control opening degree, the heating control valve 108 to the heating opening degree, the four-way reversing valve 110 to the connection direction, and the compressor 101 to operate at the operating frequency.

[0178] It should be noted that the heat pump water heater can also control the auxiliary control valve 114 to close and control the fan 112 to close.

[0179] Specifically, when the hot water control valve 107 is at a smaller fourth hot water opening degree and the main control valve 113 is at a larger fourth control opening degree, for hot water production, high-temperature and high-pressure refrigerant is output from the compressor 101, flowing sequentially through the three-way port, hot water heat exchanger 102, hot water valve 107, heating valve 108, indoor heat exchanger 109, port b of the four-way reversing valve 110, and port d of the four-way reversing valve 110, before returning to the compressor 101. For defrosting, high-temperature and high-pressure refrigerant is output from the compressor 101, flowing sequentially through the three-way port, port a of the four-way reversing valve 110, port c of the four-way reversing valve 110, outdoor heat exchanger 111, main control valve 113, heating valve 108, indoor heat exchanger 109, port b of the four-way reversing valve 110, and port d of the four-way reversing valve 110, before returning to the compressor 101. The amount of refrigerant flowing through the hot water production circuit is relatively small, while the amount flowing through the defrosting circuit is relatively large.

[0180] The defrosting control method for heat pump water heaters provided in this embodiment controls the hot water control valve to a smaller opening and the main control valve to a larger opening when the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost. This allows the energy recovered from heat to be used for defrosting and hot water production, and the energy distribution is more reasonable.

[0181] Figure 10 A schematic flowchart of Embodiment Nine of the defrosting control method for heat pump water heaters provided by the present invention is shown below. Figure 10 As shown, based on the above embodiments five and six, the defrosting control method for this heat pump water heater further includes the following steps:

[0182] S1001: Obtain the current temperature and humidity in the first space.

[0183] S1002: Based on the current temperature and humidity, determine whether heat recovery has been completed in at least one space.

[0184] S1003: Exit heat recovery mode when heat recovery is completed in at least one space.

[0185] In the above steps, to determine when to exit the heat recovery mode, it is necessary to obtain the current temperature and humidity in the first space, and then, based on the current temperature and humidity, determine whether heat recovery in at least one space has been completed. The heat recovery mode exits when heat recovery in at least one space is complete.

[0186] Specifically, when the current temperature is lower than the preset recovery completion temperature and the humidity is lower than the preset recovery completion humidity, the heat recovery of the first space is determined to be complete, the heat recovery mode is exited, and the space contained in the heat pump water heater is restored to its state before heat recovery. The preset recovery completion temperature can be 20 degrees Celsius, 25 degrees Celsius, or 27 degrees Celsius. The preset recovery completion humidity can be 40%, 50%, or 55%. This embodiment of the invention does not limit the preset recovery completion temperature and preset recovery completion humidity; they can be set according to actual conditions.

[0187] Optionally, when the heat pump water heater detects that defrosting is complete, it can also exit the heat recovery mode and restore the heat pump water heater to the state before heat recovery.

[0188] The defrosting control method for heat pump water heaters provided in this embodiment determines when to exit the heat recovery mode by measuring the temperature and humidity in the first space, thereby improving the accuracy of heat pump water heater control.

[0189] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0190] Figure 11 This is a schematic diagram of the structure of a first embodiment of the defrosting control device for a heat pump water heater provided by the present invention; as shown below. Figure 11 As shown, the defrosting control device of the heat pump water heater is integrated into the processor of the heat pump water heater. The heat pump water heater includes a processor, a water tank, and a hot water heat exchanger, an electric heater, a compressor, an indoor heat exchanger, an outdoor heat exchanger, and a control valve assembly connected to the processor. The control valve assembly includes a four-way reversing valve, a main control valve, a hot water control valve, and a heating control valve. The compressor is connected to the outdoor heat exchanger and the indoor heat exchanger respectively through the four-way reversing valve. The indoor heat exchanger is connected to the hot water heat exchanger through the heating control valve and the hot water control valve. The hot water heat exchanger is connected to the water tank for heating the water tank. The hot water heat exchanger is connected to the outdoor heat exchanger through the hot water control valve and the main control valve. The electric heater is located inside the water tank for electrically heating the water tank. The defrosting control device 1100 of the heat pump water heater includes:

[0191] The acquisition module 1101 is used to acquire the temperature of the water tank when a preset defrosting condition is detected.

[0192] The control module 1102 is used to control the working status of each control valve in the compressor, the electric heater and the control valve assembly according to the temperature of the water tank and the preset water tank temperature.

[0193] Furthermore, the control module 1102 is specifically used for:

[0194] When the temperature of the water tank is greater than or equal to the preset water tank temperature, the first hot water opening degree of the hot water control valve, the first control opening degree of the main control valve, the heating opening degree of the heating control valve, the working state of the electric heater, the connection direction of the four-way reversing valve, and the working frequency of the compressor are determined.

[0195] The system controls the hot water control valve to be at the first hot water opening degree, the main control valve to be at the first control opening degree, the heating control valve to be at the heating opening degree, the electric heater to be in the working state, the four-way reversing valve to be switched to the communication direction, and the compressor to be in the working frequency.

[0196] Furthermore, the acquisition module 1101 is specifically used to acquire the current indoor ambient temperature when the temperature of the water tank is lower than the preset water tank temperature;

[0197] Furthermore, the control module 1102 is specifically used for:

[0198] The second hot water opening degree of the hot water control valve is determined based on the indoor ambient temperature.

[0199] The second control opening degree of the main control valve, the heating opening degree of the heating control valve, the heating working state of the electric heater, the connection direction of the four-way reversing valve, and the operating frequency of the compressor are determined.

[0200] The system controls the hot water control valve to the second hot water opening degree, the main control valve to the second control opening degree, the heating control valve to the heating opening degree, the electric heater to operate in the heating working state, the four-way reversing valve to switch to the communication direction, and the compressor to operate at the operating frequency.

[0201] Furthermore, the control module 1102 is specifically used for:

[0202] When the indoor ambient temperature is greater than or equal to a preset upper limit temperature value, the second hot water opening degree of the hot water control valve is determined to be a first percentage.

[0203] When the indoor ambient temperature is less than or equal to a preset lower limit temperature value, the second hot water opening degree of the hot water control valve is determined to be a second percentage.

[0204] When the indoor ambient temperature is greater than the preset lower limit temperature value and less than the preset upper limit temperature value, the second hot water opening degree of the hot water control valve is determined to be the third percentage.

[0205] Wherein, the preset lower limit temperature value is less than the preset upper limit temperature, and the third percentage is greater than the second percentage and less than the first percentage.

[0206] The defrosting control device for the heat pump water heater provided in this embodiment is used to execute the technical solution of the processor in the heat pump water heater in any of the aforementioned method embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0207] Figure 12 This is a schematic diagram of the structure of Embodiment 2 of the defrosting control device for a heat pump water heater provided by the present invention; as shown. Figure 12 As shown, the defrosting control device 1100 of the heat pump water heater also includes:

[0208] Receiving module 1103: Receives a heat recovery command, the heat recovery command being used to indicate entering heat recovery mode;

[0209] The acquisition module 1101 is also used to acquire the heating operation time of the hot water heat exchanger based on the heat recovery command;

[0210] Furthermore, the control module 1102 is also used for:

[0211] The frosting information of the outdoor heat exchanger is determined based on the heating operation duration;

[0212] Based on the frosting information of the outdoor heat exchanger, the heating circuit of at least one space served by the heat pump water heater is turned on, and the heating circuit is turned on to recover heat from the at least one space.

[0213] Furthermore, the control module 1102 is specifically used for:

[0214] When the amount of frost on the outdoor heat exchanger is less than the preset amount of frost, the heating circuit of the first space where the heat pump water heater is used is turned on and the heating circuit of the second space where the heat pump water heater is used is turned off.

[0215] When the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost, the heating circuits of all spaces served by the heat pump water heater are turned on.

[0216] Furthermore, the control module 1102 is specifically used for:

[0217] When the amount of frost on the outdoor heat exchanger is less than the preset amount of frost, determine the third hot water opening of the hot water control valve, the third control opening of the main control valve, the heating opening of the heating control valve, the connection direction of the four-way reversing valve, and the operating frequency of the compressor.

[0218] The hot water control valve is controlled to be at the third hot water opening degree, the main control valve is controlled to be at the third control opening degree, the heating control valve is controlled to be at the heating opening degree, the four-way reversing valve is switched to the communication direction, and the compressor operates at the operating frequency.

[0219] Furthermore, the control module 1102 is specifically used for:

[0220] When the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost, the fourth hot water opening degree of the hot water control valve, the fourth control opening degree of the main control valve, the heating opening degree of the heating control valve, the connection direction of the four-way reversing valve, and the operating frequency of the compressor are determined.

[0221] The hot water control valve is controlled to be at the fourth hot water opening degree, the main control valve is controlled to be at the fourth control opening degree, the heating control valve is controlled to be at the heating opening degree, the four-way reversing valve is switched to the communication direction, and the compressor operates at the operating frequency.

[0222] The acquisition module 1101 is also used to acquire the current temperature and current humidity in the first space;

[0223] Furthermore, the control module 1102 is also used to determine whether the heat recovery of the at least one space has been completed based on the current temperature and the current humidity;

[0224] When heat recovery in at least one space is completed, the heat recovery mode is exited.

[0225] The defrosting control device for the heat pump water heater provided in this embodiment is used to execute the technical solution of the processor in the heat pump water heater in any of the aforementioned method embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0226] Figure 13 This is a schematic diagram of the structure of the heat pump water heater provided by the present invention. Figure 13 As shown, the heat pump water heater 1300 includes:

[0227] The processor 1301, memory 1302, communication interface 1303, water tank 1304, and hot water heat exchanger 1305, electric heater 1306, compressor 1307, indoor heat exchanger 1308, outdoor heat exchanger 1309 and control valve assembly 1310 connected to the processor 1301.

[0228] The control valve assembly 1310 includes a four-way reversing valve, a main control valve, a hot water control valve, and a heating control valve;

[0229] The compressor 1307 is connected to the outdoor heat exchanger 1309 and the indoor heat exchanger 1308 respectively through the four-way reversing valve. The indoor heat exchanger 1308 is connected to the hot water heat exchanger 1305 through the heating control valve and the hot water control valve. The hot water heat exchanger 1305 is connected to the water tank 1304 for heating the water tank 1304. The hot water heat exchanger 1305 is connected to the outdoor heat exchanger 1309 through the hot water control valve and the main control valve. The electric heater 1306 is located inside the water tank 1304 for electrically heating the water tank 1304.

[0230] The memory 1302 is used to store the executable instructions of the processor 1301;

[0231] The processor 1301 is configured to execute the technical solution of the processor in the heat pump water heater in any of the foregoing method embodiments by executing the executable instructions.

[0232] The processor 1301 is the defrosting control device in the above-described device embodiment.

[0233] Optionally, the memory 1302 can be either standalone or integrated with the processor 1301.

[0234] Optionally, when the memory 1302 is a device independent of the processor 1301, the heat pump water heater 1300 may further include:

[0235] A bus is used to connect the aforementioned devices.

[0236] The heat pump water heater is used to implement the technical solution of the heat pump water heater in any of the aforementioned method embodiments. Its implementation principle and technical effect are similar, and will not be repeated here.

[0237] This invention also provides a readable storage medium storing a computer program thereon, which, when executed by a processor, implements the technical solutions provided in any of the foregoing method embodiments.

[0238] This invention also provides a computer program product, including a computer program, which, when executed by a processor, is used to implement the technical solutions provided in any of the foregoing method embodiments.

[0239] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A defrosting control method for a heat pump water heater, applied to a processor in the heat pump water heater, characterized in that, The heat pump water heater includes a processor, a water tank, and a hot water heat exchanger, an electric heater, a compressor, an indoor heat exchanger, an outdoor heat exchanger, and a control valve assembly connected to the processor. The control valve assembly includes a four-way reversing valve, a main control valve, a hot water control valve, and a heating control valve. The compressor is connected to the outdoor heat exchanger and the indoor heat exchanger via the four-way reversing valve. The indoor heat exchanger is connected to the hot water heat exchanger via the heating control valve and the hot water control valve. The hot water heat exchanger is connected to the water tank for heating the water tank. The hot water heat exchanger is connected to the outdoor heat exchanger via the hot water control valve and the main control valve. The electric heater is located inside the water tank for electrically heating the water tank. The method includes: When the preset defrosting conditions are met, the temperature of the water tank is obtained; Based on the temperature of the water tank and the preset water tank temperature, the operating status of each control valve in the compressor, the electric heater, and the control valve assembly is controlled; The step of controlling the operating state of the compressor, the electric heater, and each control valve in the control valve assembly based on the temperature of the water tank and a preset water tank temperature includes: When the temperature of the water tank is lower than the preset water tank temperature, the current indoor ambient temperature is obtained; The second hot water opening degree of the hot water control valve is determined based on the indoor ambient temperature. The second control opening degree of the main control valve, the heating opening degree of the heating control valve, the heating working state of the electric heater, the connection direction of the four-way reversing valve, and the operating frequency of the compressor are determined. The system controls the hot water control valve to the second hot water opening degree, the main control valve to the second control opening degree, the heating control valve to the heating opening degree, the electric heater to operate in the heating working state, the four-way reversing valve to switch to the communication direction, and the compressor to operate at the operating frequency.

2. The method according to claim 1, characterized in that, The step of controlling the operating state of the compressor, the electric heater, and each control valve in the control valve assembly based on the temperature of the water tank and a preset water tank temperature includes: When the temperature of the water tank is greater than or equal to the preset water tank temperature, the first hot water opening degree of the hot water control valve, the first control opening degree of the main control valve, the heating opening degree of the heating control valve, the working state of the electric heater, the connection direction of the four-way reversing valve, and the working frequency of the compressor are determined. The system controls the hot water control valve to be at the first hot water opening degree, the main control valve to be at the first control opening degree, the heating control valve to be at the heating opening degree, the electric heater to be in the working state, the four-way reversing valve to be switched to the communication direction, and the compressor to be in the working frequency.

3. The method according to claim 1, characterized in that, Determining the second hot water opening degree of the hot water control valve based on the indoor ambient temperature includes: When the indoor ambient temperature is greater than or equal to a preset upper limit temperature value, the second hot water opening degree of the hot water control valve is determined to be a first percentage. When the indoor ambient temperature is less than or equal to a preset lower limit temperature value, the second hot water opening degree of the hot water control valve is determined to be a second percentage. When the indoor ambient temperature is greater than the preset lower limit temperature value and less than the preset upper limit temperature value, the second hot water opening degree of the hot water control valve is determined to be the third percentage. Wherein, the preset lower limit temperature value is less than the preset upper limit temperature value, and the third percentage is greater than the second percentage and less than the first percentage.

4. The method according to any one of claims 1 to 3, characterized in that, The method further includes: Receive a heat recovery command, the heat recovery command being used to indicate entering heat recovery mode; Based on the heat recovery command, the heating operation time of the hot water heat exchanger is obtained; The frosting information of the outdoor heat exchanger is determined based on the heating operation duration; Based on the frosting information of the outdoor heat exchanger, the heating circuit of at least one space served by the heat pump water heater is turned on, and the heating circuit is turned on to recover heat from the at least one space.

5. The method according to claim 4, characterized in that, The step of controlling the heating circuit of at least one space served by the heat pump water heater to be turned on based on the frosting information of the outdoor heat exchanger includes: When the amount of frost on the outdoor heat exchanger is less than the preset amount of frost, the heating circuit of the first space where the heat pump water heater is used is turned on and the heating circuit of the second space where the heat pump water heater is used is turned off. When the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost, the heating circuits of all spaces served by the heat pump water heater are turned on.

6. The method according to claim 5, characterized in that, The method further includes: When the amount of frost on the outdoor heat exchanger is less than the preset amount of frost, determine the third hot water opening of the hot water control valve, the third control opening of the main control valve, the heating opening of the heating control valve, the connection direction of the four-way reversing valve, and the operating frequency of the compressor. The hot water control valve is controlled to be at the third hot water opening degree, the main control valve is controlled to be at the third control opening degree, the heating control valve is controlled to be at the heating opening degree, the four-way reversing valve is switched to the communication direction, and the compressor operates at the operating frequency.

7. The method according to claim 5, characterized in that, The method further includes: When the amount of frost on the outdoor heat exchanger is greater than or equal to the preset amount of frost, the fourth hot water opening degree of the hot water control valve, the fourth control opening degree of the main control valve, the heating opening degree of the heating control valve, the connection direction of the four-way reversing valve, and the operating frequency of the compressor are determined. The hot water control valve is controlled to be at the fourth hot water opening degree, the main control valve is controlled to be at the fourth control opening degree, the heating control valve is controlled to be at the heating opening degree, the four-way reversing valve is switched to the communication direction, and the compressor operates at the operating frequency.

8. The method according to claim 5, characterized in that, The method further includes: Obtain the current temperature and humidity within the first space; Based on the current temperature and the current humidity, determine whether the heat recovery of the at least one space has been completed; When heat recovery in at least one space is completed, the heat recovery mode is exited.

9. A defrosting control device for a heat pump water heater, integrated into a processor within the heat pump water heater, characterized in that, The heat pump water heater includes a processor, a water tank, and a hot water heat exchanger, an electric heater, a compressor, an indoor heat exchanger, an outdoor heat exchanger, and a control valve assembly connected to the processor. The control valve assembly includes a four-way reversing valve, a main control valve, a hot water control valve, and a heating control valve. The compressor is connected to the outdoor heat exchanger and the indoor heat exchanger via the four-way reversing valve. The indoor heat exchanger is connected to the hot water heat exchanger via the heating control valve and the hot water control valve. The hot water heat exchanger is connected to the water tank for heating the water tank. The hot water heat exchanger is connected to the outdoor heat exchanger via the hot water control valve and the main control valve. The electric heater is located inside the water tank for electrically heating the water tank. The device includes: The acquisition module is used to acquire the temperature of the water tank when a preset defrosting condition is detected. The control module is used to control the operating status of each control valve in the compressor, the electric heater, and the control valve assembly according to the temperature of the water tank and the preset water tank temperature. The control module is specifically used to obtain the current indoor ambient temperature when the temperature of the water tank is lower than the preset water tank temperature; The second hot water opening degree of the hot water control valve is determined based on the indoor ambient temperature. The second control opening degree of the main control valve, the heating opening degree of the heating control valve, the heating working state of the electric heater, the connection direction of the four-way reversing valve, and the operating frequency of the compressor are determined. The system controls the hot water control valve to the second hot water opening degree, the main control valve to the second control opening degree, the heating control valve to the heating opening degree, the electric heater to operate in the heating working state, the four-way reversing valve to switch to the communication direction, and the compressor to operate at the operating frequency.

10. A heat pump water heater, characterized in that, include: The processor, memory, communication interface, water tank, and hot water heat exchanger, electric heater, compressor, indoor heat exchanger, outdoor heat exchanger, and control valve assembly connected to the processor; The control valve assembly includes a four-way directional valve, a main control valve, a hot water control valve, and a heating control valve. The compressor is connected to the outdoor heat exchanger and the indoor heat exchanger via the four-way reversing valve. The indoor heat exchanger is connected to the hot water heat exchanger via the heating control valve and the hot water control valve. The hot water heat exchanger is connected to the water tank for heating the water tank. The hot water heat exchanger is connected to the outdoor heat exchanger via the hot water control valve and the main control valve. The electric heater is located inside the water tank for electrically heating the water tank. The memory is used to store the executable instructions of the processor; The processor is the defrosting control device as described in claim 9.

11. A readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the defrosting control method for the heat pump water heater according to any one of claims 1 to 8.

12. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, is used to implement the defrosting control method for a heat pump water heater according to any one of claims 1 to 8.

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