Defrosting control method and device of air source heat pump unit and air source heat pump unit

Abstract

The invention relates to the technical field of heat pumps, and provides a defrosting control method and device for an air source heat pump unit and the air source heat pump unit, and the defrosting control method for the air source heat pump unit comprises the steps that under the condition that the air source heat pump unit operates in a heating mode, the temperature change rate of multiple sets of coil pipes of an outdoor heat exchanger of the air source heat pump unit is obtained; and controlling the air source heat pump unit to enter or exit a defrosting mode according to the temperature change rate of the multiple groups of coil pipes of the outdoor heat exchanger of the air source heat pump unit. According to the method, the accuracy of defrosting control can be improved, so that defrosting is timely and accurately carried out, the end of defrosting is timely judged, and the energy efficiency and normal use of the heat pump unit are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pumps, and in particular to a defrosting control method and device for an air source heat pump unit and an air source heat pump unit. Background Art

[0002] When the air source heat pump unit is running for heating in winter, due to the low outdoor ambient temperature, as the air flows through the outdoor heat exchanger coil, it may cause frost on the outdoor heat exchanger coil, affecting the stability and thermal efficiency of the air source heat pump unit.

[0003] At present, the commonly used defrosting methods include: timed defrosting, manual defrosting and defrosting according to coil temperature. These defrosting methods cannot accurately enter and exit defrosting, which can easily lead to misjudgment of defrosting or untimely defrosting, resulting in waste of energy such as electricity and heat energy, and reducing user comfort. Summary of the invention

[0004] The present invention provides a defrost control method and device for an air source heat pump unit and an air source heat pump unit, which can improve the accuracy of defrost control, thereby timely and accurately performing defrosting and timely determining the end of defrosting, thereby ensuring the energy efficiency and normal use of the heat pump unit.

[0005] The present invention provides a defrosting control method for an air source heat pump unit, comprising:

[0006] When the air source heat pump unit is operated in a heating mode, obtaining temperature change rates of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit;

[0007] The air source heat pump unit is controlled to enter or exit a defrost mode according to the temperature change rates of the multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit.

[0008] According to a defrost control method for an air source heat pump unit provided by the present invention, the steps of controlling the air source heat pump unit to enter a defrost mode according to the temperature change rate of multiple groups of coils of an outdoor heat exchanger of the air source heat pump unit specifically include:

[0009] Determine that the temperature change rates of the multiple groups of coils of the outdoor heat exchanger are simultaneously less than zero and greater than or equal to a first preset temperature change rate, and control the air source heat pump unit to enter a defrost mode for defrosting.

[0010] According to a defrost control method for an air source heat pump unit provided by the present invention, the step of controlling the air source heat pump unit to enter a defrost mode for defrosting specifically includes:

[0011] The four-way valve of the air source heat pump unit is controlled to switch to enter the defrost mode, so that the refrigerant discharged from the compressor of the air source heat pump unit flows into the outdoor heat exchanger to heat up and defrost.

[0012] According to a defrosting control method of an air source heat pump unit provided by the present invention, during the defrosting process of the air source heat pump unit, the method comprises:

[0013] Detecting the temperature change rate of multiple groups of coils of the outdoor heat exchanger;

[0014] Determine that the temperature change rates of the multiple groups of coils of the outdoor heat exchanger are simultaneously equal to the second preset temperature change rate, and the second preset temperature change rate is zero, and control the air source heat pump unit to continue defrosting.

[0015] According to a defrost control method for an air source heat pump unit provided by the present invention, the step of detecting the temperature change rate of multiple groups of coils of the outdoor heat exchanger specifically includes:

[0016] If the difference between the temperature change rate of the multiple sets of coils of the outdoor heat exchanger and the second preset temperature change rate is greater than a preset value, the temperature change rate of the multiple sets of coils of the outdoor heat exchanger is detected once every preset time period;

[0017] If the difference between the temperature change rate of the multiple sets of coils of the outdoor heat exchanger and the second preset temperature change rate is less than or equal to a preset value, the temperature change rate of the multiple sets of coils of the outdoor heat exchanger is continuously detected.

[0018] According to a defrost control method for an air source heat pump unit provided by the present invention, the step of controlling the air source heat pump unit to exit the defrost mode according to the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit comprises:

[0019] Determine that the temperature change rates of the multiple groups of coils of the outdoor heat exchanger are simultaneously greater than zero and greater than or equal to a third preset temperature change rate, and control the air source heat pump unit to exit the defrosting mode and resume the heating mode.

[0020] According to a defrost control method for an air source heat pump unit provided by the present invention, the steps of controlling the air source heat pump unit to exit a defrost mode and resume a heating mode specifically include:

[0021] The four-way valve of the air source heat pump unit is controlled to switch direction so that the refrigerant discharged from the compressor of the air source heat pump unit flows into the indoor heat exchanger of the air source heat pump unit.

[0022] According to a defrost control method for an air source heat pump unit provided by the present invention, a first temperature sensor and a second temperature sensor are provided at both ends of the coil of the outdoor heat exchanger;

[0023] The multiple groups of coil temperature change rates of the outdoor heat exchanger include: a first coil temperature change rate and a second coil temperature change rate;

[0024] wherein, according to the current coil temperature and the previous coil temperature detected by the first temperature sensor, the first coil temperature change rate is obtained;

[0025] The second coil temperature change rate is obtained according to the current coil temperature and the previous coil temperature detected by the second temperature sensor.

[0026] The present invention also provides a defrost control device for an air source heat pump unit, comprising:

[0027] An acquisition module, used for acquiring the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit when the air source heat pump unit is operated in a heating mode;

[0028] The control module is used to control the air source heat pump unit to enter or exit the defrost mode according to the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit.

[0029] The present invention also provides an air source heat pump unit, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned defrost control method of the air source heat pump unit when executing the program.

[0030] The defrost control method, device and air source heat pump unit of the air source heat pump unit provided by the present invention can effectively improve the accuracy of defrost control by determining the start and end of defrost according to the temperature change rates of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit, thereby performing defrost in a timely and accurate manner and determining the end of defrost in a timely manner, thereby ensuring the energy efficiency and normal use of the heat pump unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the present invention or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 This is one of the structural schematic diagrams of the air source heat pump unit provided by the present invention;

[0033] Figure 2 It is a schematic diagram of the heating mode principle of the air source heat pump unit provided by the present invention;

[0034] Figure 3It is a schematic diagram of the defrosting mode principle of the air source heat pump unit provided by the present invention;

[0035] Figure 4 It is one of the flow diagrams of the defrosting control method of the air source heat pump unit provided by the present invention;

[0036] Figure 5 This is the second flow chart of the defrosting control method of the air source heat pump unit provided by the present invention;

[0037] Figure 6 This is the third flow chart of the defrosting control method of the air source heat pump unit provided by the present invention;

[0038] Figure 7 This is the fourth flow chart of the defrosting control method of the air source heat pump unit provided by the present invention;

[0039] Figure 8 It is a structural schematic diagram of a defrost control device for an air source heat pump unit provided by the present invention;

[0040] Fig. 9 This is the second structural schematic diagram of the air source heat pump unit provided by the present invention.

[0041] Reference numerals:

[0042] 1: compressor; 2: indoor heat exchanger; 3: outdoor heat exchanger; 4: four-way valve;

[0043] 5: first temperature sensor; 6: second temperature sensor; 7: throttling device;

[0044] 8: outdoor fan; 9: acquisition module; 10: control module;

[0045] 11: processor; 12: communication interface; 13: memory; 14: communication bus. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] In the description of the embodiments of the present invention, it should be noted that the terms “first”, “second”, etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0048] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0049] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0050] Combine the following Figure 1-Figure 9 The present invention describes a defrosting control method and device for an air source heat pump unit and an air source heat pump unit.

[0051] According to one embodiment of the present invention, referring to Figure 1-Figure 3 As shown, the present invention provides an air source heat pump unit, which mainly includes: a compressor 1, an indoor heat exchanger 2, an outdoor heat exchanger 3 and a four-way valve 4. Among them, the exhaust port of the compressor 1 is connected to the first port a of the four-way valve 4, the air intake port of the compressor 1 is connected to the second port b of the four-way valve 4, the indoor heat exchanger 2 is connected to the third port c of the four-way valve 4, the outdoor heat exchanger 3 is connected to the fourth port d of the four-way valve 4, and the indoor heat exchanger 2 is connected to the outdoor heat exchanger 3, and a plurality of temperature sensors are provided at different positions of the coil of the outdoor heat exchanger 3, and the plurality of temperature sensors are used to detect the temperature change rate of the plurality of groups of coils of the outdoor heat exchanger 3.

[0052] In addition, the air source heat pump unit further includes: a controller, the controller is electrically connected to a plurality of temperature sensors, and the controller is configured to control the air source heat pump unit to enter or exit the defrost mode according to the temperature change rate of the plurality of coils of the outdoor heat exchanger 3. The specific control process is described below and will not be repeated here.

[0053] It should be noted that the present invention uses the temperature change rates of multiple groups of coils as the judgment conditions for entering and exiting defrost, so as to quickly and effectively judge the degree of coil temperature change, thereby accurately judging whether the coil of the outdoor heat exchanger 3 is frosted, effectively improving the accuracy of defrost control.

[0054] According to one embodiment of the present invention, referring to Figure 1 As shown, a first temperature sensor 5 and a second temperature sensor 6 are respectively provided at both ends of the inlet and outlet of the coil of the outdoor heat exchanger 3. The temperature change rate of the first coil can be detected by the first temperature sensor 5, and the temperature change rate of the second coil can be detected by the second temperature sensor 6, thereby realizing the detection and judgment of the temperature change rates of the two groups of coils. When the temperature change rates of the two groups of coils simultaneously meet the conditions for entering or exiting the defrost, the air source heat pump unit is controlled to enter the defrost mode or exit the defrost mode, which can effectively improve the accuracy of the defrost control.

[0055] According to one embodiment of the present invention, a throttling device 7 is provided between the indoor heat exchanger 2 and the outdoor heat exchanger 3, and the throttling device 7 is used to throttle the refrigerant in the pipeline.

[0056] According to one embodiment of the present invention, the air source heat pump unit further includes: an outdoor fan 8, which is arranged side by side with the outdoor heat exchanger 3 to improve air flow.

[0057] The working principle of the air source heat pump unit provided by the present invention is described below, including a heating mode and a defrosting mode.

[0058] like Figure 2 As shown, in the heating mode: the four-way valve 4 is turned on in the first direction in which the first port a is turned on with the third port c, and the second port b is turned on with the fourth port d, and the high-temperature and high-pressure refrigerant generated by the compressor 1 flows through the first port a and the third port c of the four-way valve 4 through the indoor heat exchanger 2 to release heat, then flows through the throttling device 7 to be throttled, flows through the outdoor heat exchanger 3 to absorb heat and evaporate, and then flows back to the compressor 1 through the fourth port d and the second port b of the four-way valve 4.

[0059] like Figure 3 As shown, defrost mode: when the defrost conditions are met, the four-way valve 4 is switched to reverse direction, and the four-way valve 4 is conducted in the second conducting direction in which the first port a is conducted with the fourth port d, and the second port b is conducted with the third port c, and the high-temperature and high-pressure refrigerant generated by the compressor 1 flows through the first port a and the fourth port d of the four-way valve 4 through the outdoor heat exchanger 3 to release heat, then flows through the throttling device 7 for throttling, flows through the indoor heat exchanger 2 to absorb heat and evaporate, and then flows back to the compressor 1 through the third port c and the second port b of the four-way valve 4.

[0060] The present invention controls the reversal of the four-way valve 4 in the heating mode, so that the high-temperature and high-pressure refrigerant discharged from the compressor 1 flows in reverse to the outdoor heat exchanger 3, and heats the outdoor heat exchanger 3 to achieve the purpose of defrosting.

[0061] The defrost control method of the air source heat pump unit according to the above embodiment of the present invention is described below.

[0062] According to one embodiment of the present invention, referring to Figure 4 As shown, the defrosting control method of the air source heat pump unit provided by the present invention mainly comprises the following steps:

[0063] S100, when the air source heat pump unit is operating in a heating mode, obtaining temperature change rates of multiple groups of coils of an outdoor heat exchanger of the air source heat pump unit;

[0064] S200, controlling the air source heat pump unit to enter or exit a defrost mode according to the temperature change rates of multiple groups of coils of an outdoor heat exchanger of the air source heat pump unit.

[0065] The defrost control method for an air source heat pump unit provided in an embodiment of the present invention can avoid the misjudgment problem existing in single data by simultaneously detecting the temperature change rates of multiple groups of coils, and determines the defrost entry conditions according to the temperature change rates of multiple groups of coils, thereby avoiding the untimely and inaccurate defects of timed defrosting and manual defrosting. At the same time, the defrost end conditions are determined according to the temperature change rates of multiple groups of coils, thereby avoiding the defect of heat energy waste caused by judging the delay in defrosting end according to the coil temperature.

[0066] The present invention uses the temperature change rates of multiple groups of coils as the judgment conditions for entering and exiting defrost, and can quickly and effectively judge the degree of coil temperature change, thereby accurately judging whether the outdoor heat exchanger coil is frosted, effectively improving the accuracy of defrost control, thereby timely and accurately performing defrost and timely judging the end of defrost, ensuring the energy efficiency and normal use of the heat pump unit.

[0067] According to one embodiment of the present invention, referring to Figure 5 As shown, according to the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit, the steps of controlling the air source heat pump unit to enter the defrost mode specifically include:

[0068] S201, determining that the temperature change rates of multiple groups of coils of an outdoor heat exchanger are simultaneously less than zero and greater than or equal to a first preset temperature change rate, and controlling the air source heat pump unit to enter a defrost mode for defrosting.

[0069] Specifically, when the temperature change rates of multiple groups of coils of the outdoor heat exchanger are less than zero at the same time and greater than or equal to the first preset temperature change rate, it indicates that the temperature of the outdoor heat exchanger coil drops sharply and the outdoor heat exchanger coil is frosted. At this time, the air source heat pump unit is controlled to enter the defrost mode for defrosting.

[0070] According to one embodiment of the present invention, the step of controlling the air source heat pump unit to enter the defrost mode for defrosting specifically includes: controlling the four-way valve of the air source heat pump unit to switch to enter the defrost mode, so that the refrigerant discharged from the compressor of the air source heat pump unit flows into the outdoor heat exchanger to heat up and defrost.

[0071] According to one embodiment of the present invention, referring to Figure 6 As shown, during the defrosting process of the air source heat pump unit, the following steps are included:

[0072] S202, detecting the temperature change rate of multiple groups of coils of the outdoor heat exchanger;

[0073] S203, determining that the temperature change rates of multiple groups of coils of the outdoor heat exchanger are simultaneously equal to the second preset temperature change rate, and the second preset temperature change rate is zero, and controlling the air source heat pump unit to continue defrosting.

[0074] Specifically, when the air source heat pump unit is defrosting in the defrost mode, the temperature change rates of the multiple sets of coils of the outdoor heat exchanger continue to be detected. When the temperature change rates of the multiple sets of coils of the outdoor heat exchanger are equal to the second preset temperature change rate at the same time, and the second preset temperature change rate is zero, it indicates that the coil temperature of the outdoor heat exchanger has hardly changed at this time, indicating that the defrosting has not reached the completion conditions and is still in the defrosting process. At this time, the air source heat pump unit is controlled to continue defrosting to achieve the purpose of complete defrosting.

[0075] The embodiment of the present invention can effectively improve the control accuracy of defrosting by continuing to detect the temperature change rate during the defrosting process, thereby improving the defrosting effect.

[0076] According to one embodiment of the present invention, the step of detecting the temperature change rate of multiple groups of coils of the outdoor heat exchanger specifically includes:

[0077] If the difference between the temperature change rate of the multiple sets of coils of the outdoor heat exchanger and the second preset temperature change rate is greater than the preset value, the temperature change rate of the multiple sets of coils of the outdoor heat exchanger is detected once every preset time period;

[0078] If the difference between the temperature change rate of the multiple sets of coils of the outdoor heat exchanger and the second preset temperature change rate is less than or equal to the preset value, the temperature change rate of the multiple sets of coils of the outdoor heat exchanger is continuously detected.

[0079] Specifically, when detecting the temperature change rates of multiple groups of coils of the outdoor heat exchanger, if the difference between the temperature change rates of the multiple groups of coils of the outdoor heat exchanger and the second preset temperature change rate is greater than the preset value, it means that the temperature change rate of the coils is significantly different from the second preset temperature change rate. At this time, it is sufficient to detect the data at intervals to achieve the purpose of optimized control; if the difference between the temperature change rates of the multiple groups of coils of the outdoor heat exchanger and the second preset temperature change rate is less than or equal to the preset value, it means that the temperature change rate of the coils is close to the second preset temperature change rate. At this time, continuous detection of data can avoid missed judgments, thereby effectively improving the completion of defrosting and improving the defrosting effect.

[0080] According to one embodiment of the present invention, referring to Figure 7As shown, the steps of controlling the air source heat pump unit to exit the defrost mode according to the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit include:

[0081] S204, determining that the temperature change rates of multiple groups of coils of the outdoor heat exchanger are simultaneously greater than zero and greater than or equal to a third preset temperature change rate, and controlling the air source heat pump unit to exit the defrosting mode and resume the heating mode.

[0082] Specifically, during the defrost control process, when the temperature change rates of multiple groups of coils of the outdoor heat exchanger are greater than zero at the same time and greater than or equal to the third preset temperature change rate, it indicates that the temperature of the outdoor heat exchanger coil has risen sharply, the outdoor heat exchanger coil is frost-free, and defrosting has been completed. At this time, the air source heat pump unit can be controlled to exit the defrost mode and resume the heating mode.

[0083] According to one embodiment of the present invention, the steps of controlling the air source heat pump unit to exit the defrost mode and resume the heating mode specifically include: controlling the reversing of the four-way valve of the air source heat pump unit so that the refrigerant discharged from the compressor of the air source heat pump unit flows into the indoor heat exchanger of the air source heat pump unit for heating to ensure the indoor heating effect.

[0084] According to one embodiment of the present invention, a first temperature sensor and a second temperature sensor are provided at both ends of the coil of the outdoor heat exchanger; the multiple groups of coil temperature change rates of the outdoor heat exchanger include: a first coil temperature change rate and a second coil temperature change rate; wherein, the first coil temperature change rate is obtained based on the current coil temperature and the previous coil temperature detected by the first temperature sensor; the second coil temperature change rate is obtained based on the current coil temperature and the previous coil temperature detected by the second temperature sensor.

[0085] It can be understood that the temperature change rate is the ratio of the difference between the current coil temperature and the previous coil temperature to the time change.

[0086] The embodiment of the present invention can avoid misjudgment and improve the accuracy of defrost control by simultaneously detecting the coil temperature change rates at different positions of the coil of the outdoor heat exchanger and performing defrost judgment according to the coil temperature change rates at different positions.

[0087] The defrosting control method of the air source heat pump unit provided by the present invention is described below in conjunction with a specific example, which generally includes:

[0088] (1) Entering defrost control conditions:

[0089] The previous coil temperature detected by the first temperature sensor on the outdoor heat exchanger coil is Te1, and the current coil temperature is Te2. The previous coil temperature detected by the second temperature sensor on the outdoor heat exchanger coil is Te3, and the current coil temperature is Te4. The time change is ΔT1, and the first preset temperature change rate is ΔTeA. Then the first coil temperature change rate is ΔTeA1=(Te2–Te1) / ΔT1, and the second coil temperature change rate is ΔTeA2=(Te4–Te3) / ΔT1. When ΔTeA1 and ΔTeA2 are both less than 0 and greater than or equal to ΔTeA, it indicates that the outdoor heat exchanger coil is frosted and the air source heat pump unit enters the defrost mode.

[0090] (2) Defrost control:

[0091] The four-way valve of the air source heat pump unit is controlled to change direction so that the refrigerant discharged from the compressor of the air source heat pump unit flows into the outdoor heat exchanger for heating and temperature rise, thereby achieving the purpose of defrosting.

[0092] In addition, the previous coil temperature detected by the first temperature sensor on the outdoor heat exchanger coil is Te5, and the current coil temperature is Te6. The previous coil temperature detected by the second temperature sensor on the outdoor heat exchanger coil is Te7, and the current coil temperature is Te8. The time change is ΔT2, and the second preset temperature change rate is ΔTeB. ΔTeB is 0. Then the first coil temperature change rate is ΔTeB1=(Te6–Te5) / ΔT2, and the second coil temperature change rate is ΔTeB2=(Te8–Te7) / ΔT2. When ΔTeB1 and ΔTeB2 are almost equal to ΔTeB, it means that the defrosting has not reached the completion condition and is still in the defrosting process, so defrosting continues.

[0093] (3) Exit defrost conditions:

[0094] During the defrost control process, the previous coil temperature detected by the first temperature sensor on the outdoor heat exchanger coil is Te9, and the current coil temperature is Te10. The previous coil temperature detected by the second temperature sensor on the outdoor heat exchanger coil is Te11, and the current coil temperature is Te12. The time change is ΔT3, and the third preset temperature change rate is ΔTeC. Then, the first coil temperature change rate is ΔTeC1=(Te10–Te9) / ΔT3, and the second coil temperature change rate is ΔTeC2=(Te12–Te11) / ΔT3. When ΔTeC1 and ΔTeC2 are both greater than 0 and greater than or equal to ΔTeC, it means that defrosting has been completed and the defrost mode is exited.

[0095] The defrost control device of the air source heat pump unit provided by the present invention is described below. The defrost control device of the air source heat pump unit described below and the defrost control method of the air source heat pump unit described above can be referred to each other.

[0096] According to one embodiment of the present invention, referring to Figure 8 As shown, the present invention also provides a defrost control device for an air source heat pump unit, which mainly includes: an acquisition module 9 and a control module 10. The acquisition module 9 is used to acquire the temperature change rate of multiple sets of coils of the outdoor heat exchanger of the air source heat pump unit when the air source heat pump unit is running in the heating mode; the control module 10 is used to control the air source heat pump unit to enter or exit the defrost mode according to the temperature change rate of multiple sets of coils of the outdoor heat exchanger of the air source heat pump unit.

[0097] The defrost control device of the air source heat pump unit provided in the embodiment of the present invention can effectively improve the accuracy of defrost control by determining the start and end of defrost according to the temperature change rates of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit, thereby performing defrost in a timely and accurate manner and determining the end of defrost in a timely manner, thereby ensuring the energy efficiency and normal use of the heat pump unit.

[0098] According to one embodiment of the present invention, referring to Fig. 9 As shown, the present invention also provides an air source heat pump unit, which may include: a processor 11, a communication interface 12, a memory 13 and a communication bus 14, wherein the processor 11, the communication interface 12 and the memory 13 communicate with each other through the communication bus 14. The processor 11 may call the logic instructions in the memory 13 to execute the defrost control method of the air source heat pump unit, the method comprising: when the air source heat pump unit is running in a heating mode, obtaining the temperature change rate of multiple sets of coils of the outdoor heat exchanger of the air source heat pump unit; according to the temperature change rate of multiple sets of coils of the outdoor heat exchanger of the air source heat pump unit, controlling the air source heat pump unit to enter or exit the defrost mode.

[0099] In addition, the logic instructions in the above-mentioned memory 13 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0100] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the defrost control method of the air source heat pump unit provided by the above methods, the method including: when the air source heat pump unit is operating in a heating mode, obtaining the temperature change rate of multiple groups of coils of an outdoor heat exchanger of the air source heat pump unit; according to the temperature change rate of the multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit, controlling the air source heat pump unit to enter or exit the defrost mode.

[0101] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it is implemented to execute the defrost control method of the air source heat pump unit provided by the above-mentioned methods. The method includes: when the air source heat pump unit is operating in a heating mode, obtaining the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit; according to the temperature change rate of the multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit, controlling the air source heat pump unit to enter or exit the defrost mode.

[0102] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0103] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A defrosting control method for an air source heat pump unit, It is characterized in that include: When the air source heat pump unit is operated in a heating mode, obtaining temperature change rates of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit; The air source heat pump unit is controlled to enter or exit a defrost mode according to the temperature change rates of the multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit.

2. The defrosting control method of the air source heat pump unit according to claim 1, It is characterized in that The step of controlling the air source heat pump unit to enter a defrost mode according to the temperature change rates of the multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit specifically includes: Determine that the temperature change rates of the multiple groups of coils of the outdoor heat exchanger are simultaneously less than zero and greater than or equal to a first preset temperature change rate, and control the air source heat pump unit to enter a defrost mode for defrosting.

3. The defrosting control method of the air source heat pump unit according to claim 2, It is characterized in that The step of controlling the air source heat pump unit to enter a defrost mode for defrosting specifically includes: The four-way valve of the air source heat pump unit is controlled to switch to enter the defrost mode, so that the refrigerant discharged from the compressor of the air source heat pump unit flows into the outdoor heat exchanger to heat up and defrost.

4. The defrosting control method of the air source heat pump unit according to claim 2, It is characterized in that The defrosting process of the air source heat pump unit includes: Detecting the temperature change rate of multiple groups of coils of the outdoor heat exchanger; Determine that the temperature change rates of the multiple groups of coils of the outdoor heat exchanger are simultaneously equal to the second preset temperature change rate, and the second preset temperature change rate is zero, and control the air source heat pump unit to continue defrosting.

5. The defrosting control method of the air source heat pump unit according to claim 4, It is characterized in that The step of detecting the temperature change rate of the multiple groups of coils of the outdoor heat exchanger specifically includes: If the difference between the temperature change rate of the multiple sets of coils of the outdoor heat exchanger and the second preset temperature change rate is greater than a preset value, detecting the temperature change rate of the multiple sets of coils of the outdoor heat exchanger once every preset time period; If the difference between the temperature change rate of the multiple sets of coils of the outdoor heat exchanger and the second preset temperature change rate is less than or equal to a preset value, the temperature change rate of the multiple sets of coils of the outdoor heat exchanger is continuously detected.

6. The defrosting control method of the air source heat pump unit according to claim 1, It is characterized in that The step of controlling the air source heat pump unit to exit the defrost mode according to the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit comprises: Determine that the temperature change rates of the multiple groups of coils of the outdoor heat exchanger are simultaneously greater than zero and greater than or equal to a third preset temperature change rate, and control the air source heat pump unit to exit the defrosting mode and resume the heating mode.

7. The defrosting control method of the air source heat pump unit according to claim 6, It is characterized in that The step of controlling the air source heat pump unit to exit the defrosting mode and resume the heating mode specifically includes: The four-way valve of the air source heat pump unit is controlled to switch direction so that the refrigerant discharged from the compressor of the air source heat pump unit flows into the indoor heat exchanger of the air source heat pump unit.

8. The defrosting control method for an air source heat pump unit according to any one of claims 1 to 7, It is characterized in that The coil of the outdoor heat exchanger is provided with a first temperature sensor and a second temperature sensor at both ends; The multiple groups of coil temperature change rates of the outdoor heat exchanger include: a first coil temperature change rate and a second coil temperature change rate; wherein, according to the current coil temperature and the previous coil temperature detected by the first temperature sensor, the first coil temperature change rate is obtained; The second coil temperature change rate is obtained according to the current coil temperature and the previous coil temperature detected by the second temperature sensor.

9. A defrost control device for an air source heat pump unit, It is characterized in that include: An acquisition module, used for acquiring the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit when the air source heat pump unit is operated in a heating mode; The control module is used to control the air source heat pump unit to enter or exit the defrost mode according to the temperature change rate of multiple groups of coils of the outdoor heat exchanger of the air source heat pump unit.

10. An air source heat pump unit, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, It is characterized in that When the processor executes the program, the defrost control method for the air source heat pump unit according to any one of claims 1 to 8 is implemented.

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