Air source heat pump unit defrosting control method and device and air source heat pump unit

Abstract

The present invention provides a defrost control method and device for an air source heat pump unit, and an air source heat pump unit; wherein, the method includes: when the air source heat pump unit operates in a preset mode and meets the defrost conditions, if the first outlet water temperature is not less than the first temperature threshold, controlling the air source heat pump unit to defrost in a defrost mode, and obtaining the second outlet water temperature when defrosting is completed; calculating the outlet water temperature difference between the second outlet water temperature and the preset second temperature threshold, and updating the first temperature threshold according to the outlet water temperature difference and the preset difference threshold; controlling the air source heat pump unit to operate in a preset mode, and performing defrost control on the air source heat pump unit according to the updated first temperature threshold. The above control method, by updating the first temperature threshold, ensures the outlet water temperature when entering the defrost mode, thereby avoiding the situation where the air source heat pump unit is forced to exit the defrost mode due to the outlet water temperature being too low, thereby improving the defrost effect.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical equipment, 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] In recent years, air source heat pumps, as a new type of environmentally friendly product, have been widely used in electrical equipment such as floor heating, central air conditioning, and water heaters. When the air source heat pump unit is operating in a low temperature environment, its tube-fin heat exchanger will continue to frost. If the frost is too thick, it will affect the normal operation of the air source heat pump unit. Therefore, it is necessary to defrost the tube-fin heat exchanger in time when it is frosted. During the defrosting process, in order to ensure the reliability of the plate heat exchanger, the existing method usually requires that the outlet water temperature T 出水 ≥T3 (T3 is a preset value, preferably 10℃~20℃). However, due to the low water temperature during antifreeze operation, the defrost may cause the outlet water temperature to be T 出水 In the case of <T3, the air source heat pump unit is forced to exit defrosting, resulting in unclean defrosting. Summary of the Invention

[0003] In view of this, an object of the present invention is to provide a defrost control method and device for an air source heat pump unit and an air source heat pump unit, so as to alleviate the above-mentioned technical problem of unclean defrosting.

[0004] In the first aspect, an embodiment of the present invention provides a defrost control method for an air source heat pump unit, comprising: obtaining temperature parameters when the air source heat pump unit operates in a preset mode; wherein the temperature parameters include: defrost temperature, outdoor ambient temperature and a first water outlet temperature, the first water outlet temperature being used to characterize the water outlet temperature when the air source heat pump unit operates in a preset mode; the preset modes include: anti-freeze mode or heating mode; if the defrost temperature and the outdoor ambient temperature meet the defrost conditions, determining whether the first water outlet temperature is not less than a preset first temperature threshold; if so, controlling the air source heat pump unit to defrost in the defrost mode, and obtaining a second water outlet temperature when defrosting is completed; wherein the second water outlet temperature is used to characterize the water outlet temperature when the air source heat pump unit exits the defrost mode; calculating the water outlet temperature difference between the second water outlet temperature and the preset second temperature threshold, and updating the first temperature threshold according to the water outlet temperature difference and the preset difference threshold; controlling the air source heat pump unit to operate in the preset mode, and performing defrost control on the air source heat pump unit according to the updated first temperature threshold.

[0005] The above-mentioned defrost control method for the air source heat pump unit ensures the outlet water temperature when entering the defrost mode by updating the first temperature threshold, thereby avoiding the situation where the air source heat pump unit is forced to exit the defrost mode due to the outlet water temperature being too low, thereby improving the defrost effect; at the same time, it also avoids the high energy consumption caused by the outlet water temperature being too high, thereby improving the effect of the air source heat pump unit.

[0006] Preferably, the above-mentioned preset difference threshold includes a first difference threshold and a second difference threshold; wherein, the first difference threshold is smaller than the second difference threshold; the step of updating the first temperature threshold according to the outlet water temperature difference and the preset difference threshold includes: determining whether the outlet water temperature difference is not greater than 0; if so, calculating the updated first temperature threshold based on the first temperature threshold and the first difference threshold.

[0007] Preferably, the above-mentioned step of updating the first temperature threshold according to the outlet water temperature difference and the preset difference threshold also includes: if the outlet water temperature difference is greater than 0, determining whether the outlet water temperature difference is greater than the second difference threshold; if so, calculating the difference between the outlet water temperature difference and the second difference threshold, and obtaining the updated first temperature threshold based on the first temperature threshold and the difference.

[0008] Preferably, the step of updating the first temperature threshold according to the outlet water temperature difference and the preset difference threshold further includes: if the outlet water temperature difference is greater than 0 and not greater than the second difference threshold, the first temperature threshold remains unchanged.

[0009] Preferably, before the above-mentioned step of if the defrost temperature and the outdoor ambient temperature meet the defrost conditions, the method also includes: judging whether the difference between the defrost temperature and the outdoor ambient temperature is not greater than a third difference threshold; if so, determining that the defrost temperature and the outdoor ambient temperature meet the defrost conditions.

[0010] Preferably, the above method further comprises: if the difference between the defrost temperature and the outdoor ambient temperature is greater than a third difference threshold, controlling the air source heat pump unit to continue operating in a preset mode.

[0011] Preferably, the above method further includes: if the first outlet water temperature is lower than the first temperature threshold, controlling the air source heat pump unit to operate in a heating mode until the first outlet water temperature is no lower than the first temperature threshold.

[0012] In a second aspect, an embodiment of the present invention further provides a defrost control device for an air source heat pump unit, comprising: an acquisition module for acquiring temperature parameters when the air source heat pump unit operates in a preset mode; wherein the temperature parameters include: defrost temperature, outdoor ambient temperature and a first outlet water temperature, the first outlet water temperature being used to characterize the outlet water temperature when the air source heat pump unit operates in a preset mode; the preset modes include: anti-freeze mode or heating mode; a judgment module for judging whether the first outlet water temperature is not less than a preset first temperature threshold if the defrost temperature and the outdoor ambient temperature meet the defrost conditions. value; a defrost module, for controlling the air source heat pump unit to defrost in accordance with the defrost mode, and obtaining the second outlet water temperature when the defrost is completed; wherein the second outlet water temperature is used to characterize the outlet water temperature when the air source heat pump unit exits the defrost mode; an update module, for calculating the outlet water temperature difference between the second outlet water temperature and a preset second temperature threshold, and updating the first temperature threshold according to the outlet water temperature difference and the preset difference threshold; a control module, for controlling the air source heat pump unit to operate in a preset mode, and performing defrost control on the air source heat pump unit according to the updated first temperature threshold.

[0013] In a third aspect, an embodiment of the present invention further 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 steps of the method of the first aspect when executing the computer program.

[0014] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method in the first aspect are executed.

[0015] The embodiments of the present invention bring the following beneficial effects:

[0016] The embodiment of the present invention provides a defrost control method and device for an air source heat pump unit and an air source heat pump unit. When the air source heat pump unit operates in a preset mode and meets the defrost conditions, if the first outlet water temperature is not less than the first temperature threshold, the air source heat pump unit is controlled to defrost in a defrost mode and obtain the second outlet water temperature when defrosting is completed; the outlet water temperature difference between the second outlet water temperature and the preset second temperature threshold is calculated, and the first temperature threshold is updated according to the outlet water temperature difference and the preset difference threshold; the air source heat pump unit is controlled to operate in a preset mode and defrost control is performed on the air source heat pump unit according to the updated first temperature threshold. The above control method, by updating the first temperature threshold, ensures the outlet water temperature when entering the defrost mode, thereby avoiding the air source heat pump unit being forced to exit the defrost mode due to the outlet water temperature being too low, thereby improving the defrost effect; at the same time, it also avoids the high energy consumption caused by the outlet water temperature being too high, thereby improving the effect of the air source heat pump unit.

[0017] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description and the drawings.

[0018] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. 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 any creative work.

[0020] Figure 1 A schematic structural diagram of an air source heat pump unit provided by an embodiment of the present invention;

[0021] Figure 2 A flow chart of a defrost control method for an air source heat pump unit provided by an embodiment of the present invention;

[0022] Figure 3 A flow chart of another defrost control method for an air source heat pump unit provided by an embodiment of the present invention;

[0023] Figure 4 A schematic diagram of a defrost control device for an air source heat pump unit provided by an embodiment of the present invention;

[0024] Figure 5 A schematic structural diagram of another air source heat pump unit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0026] For air source heat pump units, such as Figure 1As shown, it includes: a compressor 11, a four-way valve 12, a tube-fin heat exchanger 13, a plate heat exchanger 14, an electric heater 15 and a water pump 16; in addition, an electronic expansion valve 171 and a capillary tube 172 are provided between the tube-fin heat exchanger 13 and the plate heat exchanger 14, and an antifreeze pressure switch 173 is provided between the four-way valve 12 and the plate heat exchanger 14; and also includes a collection device, a target flow switch 191 and an exhaust valve 192. Here, the collection device includes but is not limited to a first temperature collection module 181, a second temperature collection module 182, a third temperature collection module 183 and a fourth temperature collection module 184. It should be noted that the specific structure of the air source heat pump unit can refer to the existing air source heat pump unit, and the embodiment of the present invention will not be described in detail here.

[0027] The first temperature acquisition module 181 is used to acquire the defrost temperature, the second temperature acquisition module 182 is used to acquire the outdoor ambient temperature, the third temperature acquisition module 183 is used to acquire the outlet water temperature of the plate heat exchanger 14, and the fourth temperature acquisition module 184 is used to acquire the inlet water temperature of the plate heat exchanger 14. Therefore, by forming a refrigerant flow path on the left side of the plate heat exchanger 14 and a water flow path on the right side, the refrigerant and water exchange heat in the plate heat exchanger 14, thereby achieving heating of the water path.

[0028] In actual applications, when the air source heat pump unit is powered on and not running, the low ambient temperature may cause water to freeze, resulting in water pipes or components freezing and cracking. Therefore, in order to avoid freezing and cracking of water pipes, the air source heat pump unit is equipped with an anti-freeze function. Specifically, when the outdoor ambient temperature T 外环 <0℃ and water outlet temperature T 出水 ≤T1 (T1 is a preset value, preferably 5℃~20℃), considering that the outlet water temperature is low and there is a risk of freezing and cracking, and the outlet water temperature is high, the energy consumption is high. At this time, the air source heat pump unit is controlled to heat to increase the outlet water temperature. When the outlet water temperature T is detected, 出水 ≥T2 (here T2 is a preset value, preferably 10℃~30℃, T2>T1), the air source heat pump unit is controlled to shut down.

[0029] However, when the air source heat pump unit is in antifreeze operation for a long time, the outdoor unit may be frosted and it is necessary to enter the defrost mode. The water temperature is usually low when the antifreeze mode is running. The temperature of the plate heat exchanger 14 is low during defrosting, which may cause the water in the plate heat exchanger 14 to freeze, thereby causing the plate heat exchanger 14 to crack. Therefore, in order to ensure the reliability of the plate heat exchanger 14 and ensure normal defrosting, the existing method usually requires the outlet water temperature T 出水 ≥T3 (T3 is a preset value, preferably 10℃~20℃). Since the water temperature is relatively low during antifreeze, the outlet water temperature T may appear during defrosting. 出水In the case of <T3, the air source heat pump unit is forced to exit defrosting, resulting in unclean defrosting.

[0030] Based on this, an embodiment of the present invention provides an air source heat pump unit defrost control method, device and air source heat pump unit. By updating the first temperature threshold, the outlet water temperature is guaranteed when entering the defrost mode, thereby avoiding the air source heat pump unit being forced to exit the defrost mode due to the outlet water temperature being too low, thereby improving the defrost effect; at the same time, it also avoids high energy consumption caused by the outlet water temperature being too high, thereby improving the effect of the air source heat pump unit.

[0031] To facilitate understanding of this embodiment, the embodiment of the present invention is described in detail below.

[0032] The embodiment of the present invention provides a defrost control method for an air source heat pump unit, such as Figure 2 As shown, the method includes the following steps:

[0033] Step S202: When the air source heat pump unit operates in a preset mode, temperature parameters are obtained; wherein the temperature parameters include: defrost temperature, outdoor ambient temperature, and first outlet water temperature;

[0034] Specifically, the above-mentioned preset modes include: anti-freezing mode or heating mode, that is, when the air source heat pump unit operates in anti-freezing mode or heating mode, the controller of the air source heat pump unit or the control device connected to the air source heat pump unit in communication obtains the temperature parameters of the air source heat pump unit, where the temperature parameters include but are not limited to the defrost temperature T collected by the first temperature acquisition module 181. 除霜 , the outdoor ambient temperature T collected by the second temperature collection module 182 外环 And the outlet water temperature T of the plate heat exchanger 14 collected by the third temperature collection module 183 出水 In order to distinguish the outlet water temperature in different operation modes or at different times, the embodiment of the present invention defines the outlet water temperature when the air source heat pump unit operates in a preset mode as the first outlet water temperature T 出水1 .

[0035] It should be noted that the temperature acquisition module for collecting the above-mentioned multiple temperature parameters can be a temperature sensor or a temperature sensing package, and the specific configuration can be based on actual conditions. Furthermore, the above-mentioned temperature parameters can be acquired in real time or periodically at preset intervals. Here, real-time acquisition is preferred, so that the air source heat pump unit can be judged based on the temperature parameters whether defrosting is required, thereby improving the timeliness of defrost control.

[0036] Step S204: If the defrost temperature and the outdoor ambient temperature meet the defrost condition, determine whether the first outlet water temperature is not less than a preset first temperature threshold;

[0037] For air source heat pump units, the frost condition of the air source heat pump unit is determined based on the temperature parameters obtained in real time, so as to determine whether the air source heat pump unit meets the defrost condition, that is, to determine whether the air source heat pump unit has a defrost demand. Specifically, it is determined whether the difference between the defrost temperature and the outdoor ambient temperature is not greater than the third difference threshold; if so, it is determined that the defrost temperature and the outdoor ambient temperature meet the defrost condition; otherwise, the defrost temperature and the outdoor ambient temperature do not meet the defrost condition. That is, when T 除霜 -T 外环 When ≤△T3, it is determined that the outdoor unit of the air source heat pump unit is severely frosted and needs to be defrosted, so the defrosting temperature and outdoor ambient temperature are determined to meet the defrosting conditions; when T 除霜 -T 外环 When the third difference threshold △T3 exceeds △T3, it is determined that the outdoor unit of the air source heat pump unit is not frosted or the frosting is not severe, and no defrosting is required. Therefore, it is determined that the defrost temperature and the outdoor ambient temperature do not meet the defrost conditions. At this time, the air source heat pump unit is controlled to continue operating according to the preset mode. It should be noted that the value range of the third difference threshold △T3 is 0℃ to 10℃, and the specific value of △T3 can be set according to actual conditions.

[0038] When the defrost temperature and the outdoor ambient temperature meet the defrost conditions, that is, when the air source heat pump unit has a defrost demand, it is further determined whether the first outlet water temperature is not less than the preset first temperature threshold, that is, whether T 出水1 ≥Ts1. The first temperature threshold value Ts1 preset here is used to represent that when the outlet water temperature of the air source heat pump unit is greater than Ts1, the outlet water temperature of the air source heat pump unit during defrosting is not less than T3, thereby avoiding the situation where the air source heat pump unit is forced to exit the defrost mode due to the outlet water temperature being less than T3. Therefore, by setting the first temperature threshold value Ts1 before the air source heat pump unit enters the defrost mode, and judging whether the air source heat pump unit enters the defrost mode based on the first outlet water temperature and Ts1, the problem of unclean defrosting is solved and the defrost effect of the air source heat pump unit is improved.

[0039] The initial value range of the first temperature threshold Ts1 is 20℃~30℃. 出水1 ≥Ts1, the air source heat pump unit is controlled to directly enter the defrost mode for defrosting; when T 出水1 When Ts1 is less than 1, the air source heat pump unit is controlled to operate in the heating mode to heat the outlet water until the first outlet water temperature is not less than the first temperature threshold, that is, T 出水1 ≥Ts1.

[0040] Step S206: If yes, control the air source heat pump unit to perform defrosting in the defrosting mode, and obtain the second outlet water temperature when defrosting is completed;

[0041] When T出水1 When ≥Ts1, the air source heat pump unit is controlled to defrost directly according to the defrost mode. Figure 1 The air source heat pump unit in the system mainly defrosts by reversing the four-way valve. Specifically, in the anti-freeze mode or heating mode, the air source heat pump unit compresses the refrigerant in the system into a high-temperature and high-pressure gas, which then enters the plate heat exchanger to exchange heat with water to heat the water. After the refrigerant is fully condensed in the plate heat exchanger, it is depressurized and throttled by the electronic expansion valve, and then enters the tube-fin heat exchanger to exchange heat with the ambient temperature to extract the heat energy in the air. In the defrost mode, the flow direction of the refrigerant is changed by the four-way valve. At this time, the tube-fin heat exchanger acts as a condenser and the plate heat exchanger acts as an evaporator. The air source heat pump unit compresses the refrigerant into a high-temperature and high-pressure gas, which enters the tube-fin heat exchanger to exchange heat with the ambient air. After the refrigerant is fully released and condensed in the tube-fin heat exchanger, the refrigerant liquid is depressurized and throttled by the electronic expansion valve, and then enters the plate heat exchanger to exchange heat with water to extract the heat energy in the water. The flow direction of the refrigerant in the pipeline is changed by the four-way valve to achieve the purpose of defrosting. It should be noted that in some cases, defrosting can also be combined with electric heating to improve defrosting efficiency and defrosting effect.

[0042] In addition, during the defrosting process, the defrosting temperature T is also detected in real time. 除霜 , and according to the defrost temperature T 除霜 Determine whether defrosting is completed. Specifically, when T 除霜 Not less than the preset defrost threshold T 除霜阈值 When, that is, T 除霜 ≥T 除霜阈值 At this time, the temperature of the condenser is high, and it is determined that the frost on the outdoor unit has been cleared, and the air source heat pump unit can exit the defrost mode; on the contrary, if T 除霜 <T 除霜阈值 , it means that the frost on the outdoor unit of the air source heat pump unit has not been cleared clean, and the air source heat pump unit needs to continue to defrost according to the defrost mode until T 除霜 ≥T 除霜阈值 Exit defrost mode when T 除霜阈值 The value range is 8℃~15℃.

[0043] And, when the defrosting is completed, that is, the air source heat pump unit exits the defrosting mode, the outlet water temperature at this time is obtained. For the sake of distinction and explanation, the outlet water temperature when the air source heat pump unit exits the defrosting mode is defined as the second outlet water temperature T 出水2 , so that according to the second outlet water temperature T 出水2 The first temperature threshold Ts1 is updated to ensure that the air source heat pump unit will not be forced to exit the defrost mode when it is defrosted next time, further ensuring the defrost result of the air source heat pump unit when it is defrosted next time.

[0044] Step S208, calculating the outlet water temperature difference between the second outlet water temperature and a preset second temperature threshold, and updating the first temperature threshold according to the outlet water temperature difference and the preset difference threshold;

[0045] During the defrosting process of the air source heat pump unit, when the outlet water temperature of the plate heat exchanger is T 出水 When Ts2 is less than T3, due to the risk of the plate heat exchanger freezing and cracking, the air source heat pump unit is forced to exit the defrost mode to ensure the reliable operation of the air source heat pump unit. Therefore, when the air source heat pump unit exits the defrost mode, it is necessary to compare the outlet water temperature at the time of exit with T3 to determine whether the air source heat pump unit is forced to exit the defrost mode. Therefore, the above-mentioned preset second temperature threshold Ts2 is preferably Ts2 = T3, that is, the second temperature threshold Ts2 is preferably 10℃ to 20℃.

[0046] Specifically, the outlet water temperature when the air source heat pump unit exits the defrost mode, that is, the second outlet water temperature T 出水2 Then, the outlet water temperature difference between the second outlet water temperature and the preset second temperature threshold is calculated, that is, ΔT=T 出水2 -Ts2; then, the first temperature threshold Ts1 is updated according to the outlet water temperature difference △T and the preset difference threshold to adjust the outlet water temperature condition of the air source heat pump unit when it enters defrost next time.

[0047] The preset difference thresholds include a first difference threshold ΔT1 and a second difference threshold ΔT2, and the first difference threshold ΔT1 is smaller than the second difference threshold ΔT2. Preferably, the value range of ΔT1 is 3°C to 5°C, and the value range of ΔT2 is 5°C to 10°C. The process of updating the first temperature threshold Ts1 according to the outlet water temperature difference ΔT and the preset difference threshold is as follows:

[0048] (1) If △T≤0℃, that is, T 出水2 -Ts2≤0℃; then the updated first temperature threshold is calculated based on the first temperature threshold and the first difference threshold. Here, it is preferred to add the first difference threshold △T1 on the basis of the existing first temperature threshold Ts1, that is, the adjusted Ts1=Ts1+△T1; since T 出水1 When ≥Ts1, the air source heat pump unit enters the defrost mode. Therefore, Ts1 is updated by △T1, which increases the outlet water temperature when the air source heat pump unit enters the defrost mode next time. This avoids the situation where the air source heat pump unit is forced to exit the defrost mode due to the outlet water temperature being too low during the next defrost, thereby improving the defrost effect next time.

[0049] (2) If △T>△T2, that is, T 出水2 -Ts2>△T2; then calculate the difference between the water temperature difference and the second difference threshold, and calculate the updated first temperature threshold based on the first temperature threshold and the difference. Specifically, when T出水2 -Ts2>△T2, indicating that the outlet water temperature T of the air source heat pump unit when it exits the defrost mode 出水2 The outlet water temperature T3 (i.e., Ts2) is much higher than the forced exit defrost mode. Since the high outlet water temperature leads to high energy consumption of the air source heat pump unit, the outlet water temperature condition when the air source heat pump unit enters the defrost mode next time can be appropriately lowered, that is, the first temperature threshold Ts1 is lowered to reduce energy consumption. At this time, the adjusted Ts1 = Ts1-(△T-△T2) = Ts1-(T 出水2 -Ts2-△T2); thus ensuring a maximum upper limit for the outlet water temperature. On the basis of meeting normal defrosting (i.e., the outlet water temperature when the air source heat pump unit exits the defrost mode is T3, i.e., Ts2), △T2 is higher, which not only meets the defrosting reliability requirements of the air source heat pump unit, but also avoids high energy consumption;

[0050] (3) If 0℃<△T≤△T2, it means that Ts1 can not only avoid the situation where the air source heat pump unit is forced to exit the defrost mode due to the low outlet water temperature during the next defrost, but also avoid the problem of high energy consumption caused by the high outlet water temperature. At this time, the first temperature threshold Ts1 is controlled to remain unchanged.

[0051] Therefore, the first temperature threshold is updated by the outlet water temperature difference and the preset difference threshold, which ensures that during the operation of the air source heat pump unit, not only does it enter the defrost mode for defrosting when the outlet water temperature is greater than the first temperature threshold, but it also avoids the situation where the air source heat pump unit is forced to exit the defrost mode due to the outlet water temperature being too low during defrosting; the first temperature threshold is also updated by the outlet water temperature when exiting the defrost mode, that is, the second outlet water temperature and the second temperature threshold, which ensures that the next defrost will not occur due to the outlet water temperature being too low, resulting in forced exit from the defrost mode, and at the same time avoids the situation where the outlet water temperature is too high, resulting in higher energy consumption, thereby improving the defrost effect and reliable operation of the air source heat pump unit.

[0052] Step S210: Control the air source heat pump unit to operate according to a preset mode, and perform defrost control on the air source heat pump unit according to the updated first temperature threshold.

[0053] After the above-mentioned update of the first temperature threshold is completed, return to step S202, that is, control the air source heat pump unit to continue to operate in the preset mode, repeat the above process, and perform defrost control on the air source heat pump unit according to the updated first temperature threshold, so that the first temperature threshold is updated by the second outlet water temperature and the second temperature threshold each time the air source heat pump unit exits the mode. This not only ensures that the air source heat pump unit will not be forced to exit the defrost mode due to the low outlet water temperature during the next defrost, but also avoids the situation where the outlet water temperature is too high and the energy consumption is high, thereby improving the defrosting effect and reliable operation of the air source heat pump unit.

[0054] The defrost control method for an air source heat pump unit provided in an embodiment of the present invention ensures the outlet water temperature when entering the defrost mode by updating the first temperature threshold, thereby avoiding the air source heat pump unit being forced to exit the defrost mode due to the outlet water temperature being too low, thereby improving the defrost effect; at the same time, it also avoids the high energy consumption caused by the outlet water temperature being too high, thereby improving the effect of the air source heat pump unit.

[0055] For ease of understanding, the default mode is the anti-freeze mode as an example. Figure 3 As shown, the following steps are included:

[0056] Step S302: The air source heat pump unit operates in an anti-freeze mode; at the same time, during the operation, temperature parameters are obtained in real time; wherein the temperature parameters include: defrost temperature, outdoor ambient temperature, and first outlet water temperature;

[0057] Step S304, determining whether there is a defrost requirement; that is, determining whether the defrost temperature and the outdoor ambient temperature meet the defrost conditions. If so, executing step S306; if not, returning to step S302 and continuing to operate in the anti-freeze mode;

[0058] Step S306, determine T 出水1 ≥Ts1, that is, determine whether the first outlet water temperature is not less than the preset first temperature threshold. If not, execute step S308; if yes, execute step S310; wherein, the initial value range of the first temperature threshold Ts1 is: 20℃~30℃.

[0059] Step S308: Control the air source heat pump unit to operate in heating mode to heat the outlet water until T 出水1 ≥Ts1;

[0060] Step S310, the air source heat pump unit is defrosted according to the defrost mode;

[0061] Step S312, obtaining the second outlet water temperature T when defrosting is completed 出水2 ;

[0062] Step S314, determine T 出水2 -Ts2≤0℃; if yes, go to step S316; if no, go to step S318;

[0063] Step S316, Ts1=Ts1+ΔT1; and return to step S302, that is, based on the existing first temperature threshold Ts1, the first difference threshold ΔT1 is increased to increase the outlet water temperature when the air source heat pump unit enters the defrost mode next time;

[0064] Step S318, determine T 出水2-Ts2≤△T2; if yes, go to step S320; if no, go to step S322;

[0065] Step S320, Ts1 remains unchanged and returns to step S302;

[0066] Step S322, Ts1=Ts1-(T 出水2 -Ts2-△T2); and return to step S302, that is, appropriately lowering the first temperature threshold Ts1 of the outlet water temperature condition when the air source heat pump unit enters the defrost mode next time to reduce energy consumption.

[0067] Therefore, the above-mentioned defrost control method for an air-source heat pump unit ensures the outlet water temperature when entering the defrost mode by updating the first temperature threshold, thereby avoiding the air-source heat pump unit being forced to exit the defrost mode due to excessively low outlet water temperature, thereby improving the defrost effect; at the same time, it also avoids high energy consumption caused by excessively high outlet water temperature, thereby improving the effect of the air-source heat pump unit. It should be noted that the above-mentioned steps can be specifically referred to in the aforementioned embodiment, and the embodiment of the present invention will not be described in detail here.

[0068] Corresponding to the above method embodiment, the embodiment of the present invention also provides a defrost control device for an air source heat pump unit, such as Figure 4 As shown, it includes: an acquisition module 41, a judgment module 42, a defrost module 43, an update module 44 and a control module 45; wherein the functions of each module are as follows:

[0069] An acquisition module 41 is configured to acquire temperature parameters when the air source heat pump unit operates in a preset mode. The temperature parameters include a defrost temperature, an outdoor ambient temperature, and a first outlet water temperature. The first outlet water temperature is used to represent the outlet water temperature when the air source heat pump unit operates in a preset mode. The preset mode includes an anti-freeze mode or a heating mode.

[0070] A judgment module 42 is configured to judge whether the first outlet water temperature is not less than a preset first temperature threshold if the defrost temperature and the outdoor ambient temperature meet the defrost condition;

[0071] The defrost module 43 is used to control the air source heat pump unit to defrost according to the defrost mode and obtain the second outlet water temperature when the defrost is completed; wherein the second outlet water temperature is used to represent the outlet water temperature when the air source heat pump unit exits the defrost mode;

[0072] An updating module 44 is configured to calculate a water outlet temperature difference between the second water outlet temperature and a preset second temperature threshold, and to update the first temperature threshold according to the water outlet temperature difference and the preset difference threshold;

[0073] The control module 45 is used to control the air source heat pump unit to operate according to a preset mode and perform defrost control on the air source heat pump unit according to the updated first temperature threshold.

[0074] The defrost control device for an air source heat pump unit provided in an embodiment of the present invention ensures the outlet water temperature when entering the defrost mode by updating the first temperature threshold, thereby avoiding the air source heat pump unit being forced to exit the defrost mode due to the outlet water temperature being too low, thereby improving the defrost effect; at the same time, it also avoids high energy consumption caused by the outlet water temperature being too high, thereby improving the effect of the air source heat pump unit.

[0075] Preferably, the above-mentioned preset difference threshold includes a first difference threshold and a second difference threshold; wherein, the first difference threshold is smaller than the second difference threshold; the above-mentioned update module 44 is also used to: determine whether the water temperature difference is not greater than 0; if so, the updated first temperature threshold is calculated based on the first temperature threshold and the first difference threshold.

[0076] Preferably, the above-mentioned update module 44 is also used to: if the outlet water temperature difference is greater than 0, determine whether the outlet water temperature difference is greater than the second difference threshold; if so, calculate the difference between the outlet water temperature difference and the second difference threshold, and calculate the updated first temperature threshold based on the first temperature threshold and the difference.

[0077] Preferably, the updating module 44 is further configured to: if the outlet water temperature difference is greater than 0 and not greater than a second difference threshold, keep the first temperature threshold unchanged.

[0078] Preferably, before the defrost temperature and the outdoor ambient temperature meet the defrost condition, the device also includes: judging whether the difference between the defrost temperature and the outdoor ambient temperature is not greater than a third difference threshold; if so, determining that the defrost temperature and the outdoor ambient temperature meet the defrost condition.

[0079] Preferably, the above device further comprises: if the difference between the defrost temperature and the outdoor ambient temperature is greater than a third difference threshold, controlling the air source heat pump unit to continue operating in a preset mode.

[0080] Preferably, the above device further includes: if the first outlet water temperature is lower than the first temperature threshold, controlling the air source heat pump unit to operate in a heating mode until the first outlet water temperature is no lower than the first temperature threshold.

[0081] The defrost control device for an air source heat pump unit provided in an embodiment of the present invention has the same technical features as the defrost control method for an air source heat pump unit provided in the above embodiment, and therefore can also solve the same technical problems and achieve the same technical effects.

[0082] An embodiment of the present invention further provides an air source heat pump unit, comprising a processor and a memory, wherein the memory stores machine executable instructions that can be executed by the processor, and the processor executes the machine executable instructions to implement the above-mentioned defrost control method of the air source heat pump unit.

[0083] See also Figure 5 As shown, the air source heat pump unit includes a processor 100 and a memory 101. The memory 101 stores machine executable instructions that can be executed by the processor 100. The processor 100 executes the machine executable instructions to implement the above-mentioned air source heat pump unit defrost control method.

[0084] Furthermore, Figure 5 The air source heat pump unit shown further includes a bus 102 and a communication interface 103 , and the processor 100 , the communication interface 103 and the memory 101 are connected via the bus 102 .

[0085] Among them, the memory 101 may include high-speed random access memory (RAM), and may also include non-volatile memory (non-volatile memory), such as at least one disk storage. The communication connection between the system network element and at least one other network element is realized through at least one communication interface 103 (which can be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. can be used. The bus 102 can be an ISA (Industrial Standard Architecture, industrial standard structure bus) bus, PCI (Peripheral Component Interconnect, peripheral component interconnect standard) bus or EISA (Enhanced Industry Standard Architecture, extended industry standard architecture) bus, etc. The above-mentioned bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, Figure 5 Only one bidirectional arrow is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0086] The processor 100 may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method can be completed by hardware integrated logic circuits in the processor 100 or software instructions. The above processor 100 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in conjunction with the embodiments of the present invention can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium well-known in the art, such as a random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or register. The storage medium is located in the memory 101. The processor 100 reads the information in the memory 101 and, in conjunction with its hardware, completes the steps of the method of the aforementioned embodiment.

[0087] This embodiment also provides a machine-readable storage medium, which stores machine-executable instructions. When the machine-executable instructions are called and executed by a processor, the machine-executable instructions prompt the processor to implement the above-mentioned air source heat pump unit defrost control method.

[0088] The defrost control method and device for an air source heat pump unit and the computer program product for an air source heat pump unit provided in the embodiments of the present invention include a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the method described in the previous method embodiments. For specific implementation, please refer to the method embodiments and will not be repeated here.

[0089] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described systems and devices can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0090] In addition, in the description of the embodiments of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0091] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present invention, 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. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0092] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0093] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed by the present invention, or replace some of the technical features therein with equivalents. Such modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A defrost control method for an air source heat pump unit, characterized in that: include: When the air source heat pump unit operates in a preset mode, temperature parameters are obtained; wherein the temperature parameters include: a defrost temperature, an outdoor ambient temperature, and a first outlet water temperature, the first outlet water temperature being used to represent the outlet water temperature when the air source heat pump unit operates in the preset mode; the preset mode includes: an anti-freeze mode or a heating mode; If the defrost temperature and the outdoor ambient temperature meet the defrost condition, determining whether the first outlet water temperature is not less than a preset first temperature threshold; If so, controlling the air source heat pump unit to perform defrosting in a defrosting mode, and obtaining a second outlet water temperature when defrosting is completed; wherein the second outlet water temperature is used to represent the outlet water temperature when the air source heat pump unit exits the defrosting mode; Calculating a water outlet temperature difference between the second water outlet temperature and a preset second temperature threshold, and updating the first temperature threshold according to the water outlet temperature difference and the preset difference threshold; The air source heat pump unit is controlled to operate according to the preset mode, and defrost control is performed on the air source heat pump unit according to the updated first temperature threshold.

2. The method according to claim 1, characterized in that The preset difference threshold includes a first difference threshold and a second difference threshold; wherein the first difference threshold is smaller than the second difference threshold; The step of updating the first temperature threshold according to the outlet water temperature difference and a preset difference threshold comprises: Determine whether the outlet water temperature difference is not greater than 0; If so, an updated first temperature threshold is calculated according to the first temperature threshold and the first difference threshold.

3. The method according to claim 2, characterized in that The step of updating the first temperature threshold according to the outlet water temperature difference and a preset difference threshold further includes: If the outlet water temperature difference is greater than 0, determining whether the outlet water temperature difference is greater than the second difference threshold; If so, the difference between the outlet water temperature difference and the second difference threshold is calculated, and the updated first temperature threshold is calculated based on the first temperature threshold and the difference.

4. The method according to claim 3, characterized in that The step of updating the first temperature threshold according to the outlet water temperature difference and a preset difference threshold further includes: If the outlet water temperature difference is greater than 0 and not greater than the second difference threshold, the first temperature threshold remains unchanged.

5. The method according to claim 1, wherein Before the step of if the defrost temperature and the outdoor ambient temperature meet the defrost condition, the method further includes: determining whether a difference between the defrost temperature and the outdoor ambient temperature is not greater than a third difference threshold; If so, it is determined that the defrost temperature and the outdoor ambient temperature meet the defrost condition.

6. The method according to claim 5, characterized in that The method further comprises: If the difference between the defrost temperature and the outdoor ambient temperature is greater than the third difference threshold, the air source heat pump unit is controlled to continue operating according to the preset mode.

7. The method according to claim 1, characterized in that The method further comprises: If the first outlet water temperature is lower than the first temperature threshold, the air source heat pump unit is controlled to operate in the heating mode until the first outlet water temperature is no lower than the first temperature threshold.

8. A defrost control device for an air source heat pump unit, characterized in that: include: an acquisition module, configured to acquire temperature parameters when the air source heat pump unit operates in a preset mode; wherein the temperature parameters include: a defrost temperature, an outdoor ambient temperature, and a first outlet water temperature, wherein the first outlet water temperature is used to represent the outlet water temperature when the air source heat pump unit operates in the preset mode; the preset mode includes: an anti-freeze mode or a heating mode; a judgment module, configured to judge whether the first outlet water temperature is not less than a preset first temperature threshold if the defrost temperature and the outdoor ambient temperature meet a defrost condition; a defrost module, configured to control the air source heat pump unit to defrost in a defrost mode and obtain a second outlet water temperature when defrosting is completed; wherein the second outlet water temperature is used to represent the outlet water temperature when the air source heat pump unit exits the defrost mode; an updating module, configured to calculate a water outlet temperature difference between the second water outlet temperature and a preset second temperature threshold, and update the first temperature threshold according to the water outlet temperature difference and the preset difference threshold; A control module is used to control the air source heat pump unit to operate according to the preset mode and to perform defrost control on the air source heat pump unit according to the updated first temperature threshold.

9. An air source heat pump unit, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are executed.

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