A heat pump air conditioner defrosting control method, device and equipment

Abstract

The present application provides a control method, device and equipment for defrosting a heat pump air conditioner. In the method, the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the suction pressure of the compressor are obtained; the temperature difference between the two ends of the evaporator is determined according to the ambient temperature and the fin temperature; the thickness of the frost layer is calculated according to the temperature difference between the two ends of the evaporator, the frosting time and the air humidity; based on the thickness of the frost layer, the ambient temperature, the fin temperature, the evaporation temperature and the suction pressure of the compressor, it is judged whether the defrosting entry conditions are met; if the defrosting entry conditions are met, the heat pump air conditioner is controlled to enter the defrosting operation, and the defrosting time of the defrosting operation is obtained; when the frost layer thickness and / or the defrosting time reach the defrosting exit conditions, the defrosting operation is exited. The above method can more accurately determine the timing of the defrosting operation by determining the thickness of the frost layer, and combining the frost layer thickness and more data, effectively avoiding the situation of mistaken defrosting.

Description

Technical Field

[0001] The present application relates to the field of defrosting technology, and in particular to a control method, device and equipment for defrosting a heat pump air conditioner. Background Art

[0002] Heat pump air conditioners refer to air conditioning systems that use heat pump technology for cooling and heating. During the operation of heat pump air conditioners, frost easily forms on the evaporator surface, affecting heat exchange efficiency and system performance. Therefore, effective defrost control logic is crucial to maintain the normal operation of heat pump air conditioners.

[0003] At present, a method commonly used in rail heat pump air conditioners is referred to as the TT (Temperature-Time) defrost control method. This method takes the outdoor coil temperature into account based on the amount of time. It is a further method of timed defrosting. When the sensor measures that the surface temperature of the evaporator fin tube and the heating time of the heat pump have reached the set value, defrosting begins. This method has a single control logic calculation method, which is prone to false defrosting when the actual operating environment is complex and changeable. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide a heat pump air conditioner defrosting control method, device and equipment to effectively avoid the situation of false defrosting.

[0005] To achieve the above objectives, the present application discloses the following technical solutions:

[0006] In a first aspect, the present application provides a heat pump air conditioner defrosting control method, comprising:

[0007] Obtain the ambient temperature, evaporator frosting time, air humidity, evaporation temperature, evaporator fin temperature, and compressor suction pressure;

[0008] Determining a temperature difference between two ends of the evaporator according to the ambient temperature and the fin temperature;

[0009] Calculating the thickness of the frost layer according to the temperature difference between the two ends of the evaporator, the frosting time and the air humidity;

[0010] determining whether a defrost entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature, and the compressor suction pressure;

[0011] If the defrost entry condition is met, the heat pump air conditioner is controlled to enter the defrost operation, and the defrost time of the defrost operation is obtained;

[0012] When the frost layer thickness and / or the defrost time of the defrost operation reaches a defrost exit condition, the defrost operation is exited.

[0013] Optionally, the method further includes: obtaining the working time and the working frequency of the compressor, and judging whether the defrost entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure, including:

[0014] If the first and second conditions are met, the defrost entry conditions are met:

[0015] The first condition includes: the ambient temperature is in a first preset temperature interval, and the first difference between the ambient temperature and the fin temperature is greater than or equal to a first temperature threshold, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to a second temperature threshold, and the frost layer thickness is greater than or equal to a frost layer thickness setting value; or, the ambient temperature is in a second preset temperature interval, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to a third temperature threshold, and the frost layer thickness is greater than or equal to the frost layer thickness setting value;

[0016] The second condition includes: the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working time of the compressor meets the defrost time condition; the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working frequency of the compressor meets the preset working frequency threshold condition and reaches the preset working time.

[0017] Optionally, if it is determined that the first condition and the second condition are met, then determining that the defrost entry condition is met includes:

[0018] If it is determined that the first condition, the second condition, the third condition and the fourth condition are met, it is determined that the defrost entry condition is met; wherein the third condition includes: the fin temperature is less than or equal to a fourth temperature threshold;

[0019] The fourth condition includes: the ambient temperature is less than or equal to a fifth temperature threshold.

[0020] Optionally, the method further comprises: obtaining the air supply temperature of the heat pump air conditioner;

[0021] The defrost exit condition includes any one of the following:

[0022] The frost layer thickness is lower than a preset thickness threshold;

[0023] The defrost time of the defrost operation reaches the preset defrost time;

[0024] When the supply air temperature is greater than or equal to a sixth temperature threshold, the sum of the evaporation temperature and the supply air temperature is less than a seventh temperature threshold; or, when the supply air temperature is less than the sixth temperature threshold, the evaporation temperature is less than an eighth temperature threshold.

[0025] Optionally, the method further includes:

[0026] Determine the actual defrost time of the defrost operation;

[0027] The preset defrost time is updated based on the actual defrost time.

[0028] Optionally, the updating of the preset defrost time based on the actual defrost time includes:

[0029] Determining that the actual defrost time is within a percentage interval of the preset defrost time;

[0030] Based on the percentage interval, the preset defrost time is updated.

[0031] Optionally, the method further includes: obtaining the return air temperature of the heat pump air conditioner, and judging whether the defrosting entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure, including:

[0032] Whether the defrost entry condition is met is determined based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature, the compressor suction pressure and the return air temperature.

[0033] Optionally, the method further includes: acquiring the working time of the compressor, and the interval time between the time of entering the defrost operation and the last defrost operation;

[0034] Then, judging whether the defrost entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure includes:

[0035] Whether a defrost entry condition is met is determined based on the working time, the interval time, the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure.

[0036] In a second aspect, the present application provides a heat pump air conditioner defrosting control device, comprising:

[0037] An acquisition unit, used for acquiring the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the suction pressure of the compressor;

[0038] a determination unit, configured to determine a temperature difference between two ends of the evaporator according to the ambient temperature and the fin temperature;

[0039] A calculation unit, used for calculating according to the temperature difference between the two ends of the evaporator, the frosting time and the air humidity to obtain the thickness of the frost layer;

[0040] a judging unit, configured to judge whether a defrosting entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure;

[0041] An entry unit, used for controlling the heat pump air conditioner to enter a defrost operation if a defrost entry condition is met, and obtaining a defrost time for the defrost operation;

[0042] The exit unit is used to exit the defrost operation when the frost layer thickness and / or the defrost time of the defrost operation reaches a defrost exit condition.

[0043] In a third aspect, the present application provides a heat pump air conditioner defrosting control device, comprising:

[0044] Memory for storing computer programs;

[0045] A processor is used to execute the computer program stored in the memory to implement the steps of the method for controlling defrosting of a heat pump air conditioner as provided in the first aspect.

[0046] The present application provides a heat pump air conditioner defrosting control method, device and equipment, in which the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the compressor suction pressure are obtained; the temperature difference at both ends of the evaporator is determined according to the ambient temperature and the fin temperature; the thickness of the frost layer is calculated according to the temperature difference at both ends of the evaporator, the frosting time and the air humidity; based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure, it is judged whether the defrosting entry conditions are met; if the defrosting entry conditions are met, the heat pump air conditioner is controlled to enter the defrosting operation, and the defrosting time of the defrosting operation is obtained; when the frost layer thickness and / or the defrosting time reach the defrosting exit conditions, the defrosting operation is exited. The above method can more accurately determine the timing of the defrosting operation by determining the frost layer thickness, and combining the frost layer thickness and more data, effectively avoiding the situation of mistaken defrosting. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application, and a person skilled in the art can also obtain other drawings based on these drawings.

[0048] Figure 1 is a schematic diagram of the principle of a heat pump system for an air conditioner provided in an embodiment of the present application;

[0049] Figure 2 It is a flow chart of a heat pump air conditioner defrosting control method provided in an embodiment of the present application;

[0050] Figure 3 It is a schematic diagram of an actual defrost time being within a percentage interval of a preset defrost time provided by an embodiment of the present application;

[0051] Figure 4 It is a schematic diagram of a process for updating a preset defrost time provided in an embodiment of the present application;

[0052] Figure 5 It is a schematic diagram of the operating status of various components of a heat pump air conditioner in the defrost stage provided by an embodiment of the present application;

[0053] Figure 6 It is a logic diagram of a heat pump air conditioner defrosting control method provided in an embodiment of the present application;

[0054] Figure 7 It is a structural schematic diagram of a defrost device for defrosting a heat pump air conditioner provided in an embodiment of the present application. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0056] To facilitate understanding of the technical solution provided by this application, the background technology involved in this application will be described below.

[0057] like Figure 1 As shown, Figure 1 It is a schematic diagram of the principle of a heat pump system for an air conditioner provided in an embodiment of the present application; the system is mainly composed of four major components: a compressor, a condenser, an expansion valve and an evaporator, and is connected by pipes to form a closed circulation system.

[0058] In cooling mode, see Figure 1In the middle dotted line, the low-temperature, low-pressure gaseous refrigerant is sucked in and compressed by the compressor to become a high-temperature, high-pressure gaseous refrigerant. Subsequently, the high-temperature, high-pressure gaseous refrigerant enters the condenser, where it exchanges heat with the outside air (condensing fan), and the refrigerant releases heat, gradually cools and liquefies into a high-temperature, high-pressure liquid refrigerant. Next, the liquid refrigerant passes through the expansion valve, where the pressure drops sharply and the temperature also drops, becoming a low-temperature, low-pressure liquid and gaseous mixed refrigerant. Finally, the low-temperature, low-pressure mixed refrigerant enters the evaporator, where it absorbs heat from the indoor air (ventilator), and the refrigerant quickly evaporates into a low-temperature, low-pressure gaseous refrigerant, thereby achieving the purpose of lowering the indoor temperature.

[0059] In heating mode, see Figure 1 In the solid line part, the flow direction of the refrigerant is changed by the four-way reversing valve. At this time, the evaporator becomes the condenser, and the condenser becomes the evaporator. After being compressed by the compressor, the low-temperature and low-pressure gaseous refrigerant enters the evaporator (the condenser at this time), releases heat to the room, and raises the indoor temperature; while in the condenser (the evaporator at this time), the refrigerant absorbs heat from the outdoor environment.

[0060] During the whole process, the refrigerant circulates continuously to realize the cooling and heating functions of the air conditioner. During the patrol process of the system, when the surface temperature of the evaporator is lower than the air dew point temperature and lower than 0°C, the water vapor in the air will condense and frost on the surface of the evaporator. The increase of frost layer will increase the heat transfer resistance of the evaporator, reduce the heat exchange efficiency, increase energy consumption, and may even cause system failure.

[0061] At present, a method commonly used by heat pump air conditioners is referred to as TT (Temperature-Time) defrost control method. This method considers the outdoor coil temperature based on the amount of time. It is a further method of timed defrosting. When the sensor measures that the surface temperature of the evaporator fin tube and the heating time of the heat pump have reached the set value, defrosting begins. However, the unreasonable installation position of the temperature sensor can easily lead to inaccurate judgment of the end of frosting, incomplete defrosting, and cannot take into account the changes in ambient temperature and humidity, which is prone to false defrosting. In addition, since the defrost timer is often automatically reset after shutdown, the unit cannot avoid the phenomenon of "no frost removal" caused by "no defrosting during shutdown" under partial load operation.

[0062] The existing defrost control method has a single control logic calculation method, which can easily lead to problems such as reduced heating capacity, reduced energy efficiency ratio (Coefficient Of Performance, COP), loss of heating capacity, and poor user comfort.

[0063] Based on this, the present application provides a heat pump air conditioner defrosting control method, device and equipment. In a heat pump air conditioner defrosting control method, the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the compressor suction pressure are obtained; the temperature difference at both ends of the evaporator is determined according to the ambient temperature and the fin temperature; the frost layer thickness is calculated according to the temperature difference at both ends of the evaporator, the frosting time, and the air humidity; based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature, and the compressor suction pressure, it is determined whether the defrosting entry conditions are met; if the defrosting entry conditions are met, the heat pump air conditioner is controlled to enter the defrosting operation; when the defrosting exit conditions are met, the defrosting operation is exited. The above method can more accurately determine the timing of the defrosting operation by determining the frost layer thickness, and combining the frost layer thickness and more data, effectively avoiding the situation of mistaken defrosting.

[0064] To facilitate understanding of the technical solution provided by the present application, a heat pump air conditioner defrost control method provided by the present application will be described below in conjunction with the accompanying drawings. The present application does not limit the specific application scenarios of the method. As an example, the defrost control method can be applied to a vehicle to control the heat pump air conditioner on the vehicle.

[0065] See also Figure 2 , this figure is a flow chart of a heat pump air conditioner defrosting control method provided in an embodiment of the present application, and the method includes S101-S106.

[0066] S101: Acquire the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the suction pressure of the compressor.

[0067] In the embodiment of the present application, the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the suction pressure of the compressor can be obtained through sensors or related monitoring devices. For example, the ambient temperature and the fin temperature of the evaporator can be obtained through a temperature sensor, the air humidity can be obtained through a humidity sensor, the evaporator starts to frost through the sensor, and the frosting time of the evaporator can be determined through a clock controller.

[0068] It is understandable that the ambient temperature is the fresh air temperature, which can represent the temperature of the evaporator inlet side. The evaporation temperature refers to the saturation temperature of the refrigerant corresponding to the evaporation pressure. The present application can calculate the saturation temperature of the refrigerant after obtaining the pressure based on the pressure sensor, thereby obtaining the evaporation temperature.

[0069] S102: Determine the temperature difference between two ends of the evaporator according to the ambient temperature and the fin temperature.

[0070] The present application does not limit the specific method of determining the temperature difference between the two ends of the evaporator based on the ambient temperature and the fin temperature. As an example, the present application can directly regard the fin temperature of the evaporator as the air outlet temperature of the evaporator. By subtracting the ambient temperature from the air outlet temperature of the evaporator, the temperature difference between the two ends of the evaporator can be obtained.

[0071] It is understandable that the temperature at the evaporator outlet will actually have an error with the fin temperature. As another example, the present application can determine the temperature correction value between the evaporator outlet temperature and the fin temperature in advance through experiments. When the fin temperature is obtained, the evaporator outlet temperature can be obtained by adding the temperature correction value to the fin temperature, and then the evaporator outlet temperature can be subtracted from the ambient temperature to obtain the temperature difference between the two ends of the evaporator.

[0072] S103: Calculate the thickness of the frost layer according to the temperature difference between the two ends of the evaporator, the frosting time and the air humidity.

[0073] It is understandable that the frost layer thickness represents the thickness of the frost on the evaporator. The present application does not limit the specific method of calculating the frost layer thickness based on the temperature difference between the two ends of the evaporator, the frosting time and the air humidity.

[0074] S104: Determine whether defrost entry conditions are met based on frost layer thickness, ambient temperature, fin temperature, evaporation temperature, and compressor suction pressure.

[0075] In the embodiment of the present application, after the frost layer thickness is obtained, it is determined whether the defrost entry conditions are met based on the frost layer thickness, ambient temperature, fin temperature, evaporation temperature and compressor suction pressure.

[0076] The present application does not limit the specific determination of whether the defrost entry condition is met based on the frost layer thickness, ambient temperature, fin temperature, evaporation temperature and compressor suction pressure. As an example, the present application may also obtain the working time of the compressor and the working frequency of the compressor. Then S104 determines whether the defrost entry condition is met based on the frost layer thickness, ambient temperature, fin temperature, evaporation temperature and compressor suction pressure, including: if it is determined that the first condition and the second condition are met, then it is determined that the defrost entry condition is met:

[0077] The first condition includes: the ambient temperature is in a first preset temperature range, and the first difference between the ambient temperature and the fin temperature is greater than or equal to the first temperature threshold, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to the second temperature threshold, and the frost layer thickness is greater than or equal to the frost layer thickness setting value; or, the ambient temperature is in a second preset temperature range, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to the third temperature threshold, and the frost layer thickness is greater than or equal to the frost layer thickness setting value.

[0078] It can be understood that the first condition is divided into two situations. The first situation is: when the ambient temperature is in the first preset temperature range, the first difference between the ambient temperature and the fin temperature is greater than or equal to the first temperature threshold, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to the second temperature threshold, and the frost layer thickness is greater than or equal to the frost layer thickness setting value. The second situation is: when the ambient temperature is in the second preset temperature range, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to the third temperature threshold, and the frost layer thickness is greater than or equal to the frost layer thickness setting value.

[0079] The present application does not limit the relationship between the first preset temperature interval and the second preset temperature interval. As an example, the temperature value of the first preset temperature interval may be greater than the temperature value of the second preset temperature interval, so that the second temperature threshold is greater than the third temperature threshold. As an example, the first preset temperature interval is [-5,12], the second preset temperature interval is [-15,5), the first temperature threshold is 12.5°C, the second temperature threshold is 16°C, and the third temperature threshold is 8°C.

[0080] The first case that satisfies the first condition is: -5 ℃ ≤ ambient temperature ≤ 12 ℃, and ambient temperature - fin temperature ≥ 12.5 ℃, and ambient temperature - evaporation temperature ≥ 16 ℃, and frost thickness ≥ frost thickness setting value. The second case that satisfies the first condition is when -15 ℃ ≤ ambient temperature < -5 ℃, ambient temperature - evaporation temperature ≥ 8 ℃; frost thickness ≥ frost thickness setting value. This application does not limit the specific value of the frost thickness setting value, and the frost thickness setting value can be determined according to actual needs.

[0081] The second condition includes: the compressor suction pressure meets the preset pressure threshold, and it is determined that the compressor working time meets the defrost time condition; the compressor suction pressure meets the preset pressure threshold, and it is determined that the compressor working frequency meets the preset working frequency threshold and reaches the preset working time.

[0082] It can be understood that the second condition is also divided into two situations. The first situation is that the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working time of the compressor meets the defrosting time condition. The second situation is that the suction pressure of the compressor meets the preset pressure threshold, the working frequency of the compressor meets the preset working frequency threshold condition and reaches the preset working time.

[0083] The present application does not limit the specific value of the preset pressure threshold. As an example, the preset pressure threshold can be determined according to the return air temperature, which is equivalent to the indoor temperature. Specifically, the preset pressure threshold can be determined by the following formula:

[0084] Y = P(Tdf);

[0085] Wherein, Tdf=X-return air temperature, X is the set value, which can be set in the range of (-10 ℃ ~+5 ℃), Y represents the preset pressure threshold, and P represents the functional relationship between temperature and the preset pressure threshold. If Y≤0.25Mpa is calculated, then Y=0.25Mpa. As an example, the present application can take Tdf as the bubble point temperature of R407C refrigerant.

[0086] The present application does not limit the specific content of the preset operating frequency threshold condition. As an example, the preset operating frequency threshold condition may be the minimum operating frequency of the compressor, and the preset operating time may be 60 seconds.

[0087] That is, the second situation in the second condition includes: the suction pressure of the compressor meets the preset pressure threshold, and the duration of the compressor working at the minimum operating frequency reaches 60 seconds.

[0088] The specific method of determining whether the working time of the compressor meets the defrost time condition in this application is, as an example, the application can determine whether the working time of the compressor meets the defrost time condition according to the following formula:

[0089] Z = T1 / TM1n + T2 / TM2n;

[0090] TM1n= TM1 (n-1) +5*c;

[0091] TM2n= TM2(n-1)+5*c;

[0092] ;

[0093] In the formula, Z represents the working time ratio, T1 represents the working time of the compressor at a temperature greater than or equal to the preset ambient temperature, and T2 represents the working time of the compressor at a temperature less than the preset ambient temperature. Indicates the thickness of the frost layer, Indicates the set value of frost thickness, n indicates the number of defrosts. TM1n indicates the function of the time threshold of the compressor at a temperature greater than or equal to the preset ambient temperature, TM2n indicates the function of the time threshold of the compressor at a temperature less than the preset ambient temperature, c indicates the relevant parameter, and the value of c is related to the thickness of the frost layer; when n is 1, it indicates the first defrost. For the first defrost, TM1n defaults to 30 minutes and TM2n defaults to 60 minutes. During the second defrost, TM1n and TM2n are updated using the above formula. The preset ambient temperature can be -8 ℃.

[0094] The present application can determine the working time proportion Z, and when it is determined that the working time proportion Z is greater than 100%, it is determined that the working time of the compressor meets the defrost time condition. As an example, the present application resets the cumulative number of defrost times after mode switching or power failure and power on again. When the present application is applied to a vehicle, the mode switching may include: switching of precooling, preheating, cooling, heating, ventilation, emergency ventilation, and car wash modes.

[0095] The present application can more accurately determine the timing of the defrost operation through the above-mentioned first condition and the second condition, and effectively avoid the situation of mistaken defrosting.

[0096] As a possible implementation manner, if it is determined that the first condition and the second condition are met, then it is determined that the defrost entry condition is met, including: if it is determined that the first condition, the second condition, the third condition and the fourth condition are met, then it is determined that the defrost entry condition is met.

[0097] Wherein, the third condition includes: the fin temperature is less than or equal to the fourth temperature threshold. The fourth condition includes: the ambient temperature is less than or equal to the fifth temperature threshold.

[0098] The present application does not limit specific values ​​of the fourth temperature threshold and the fifth temperature threshold. As an example, the fourth temperature threshold may be -4°C; the fifth temperature threshold may be 15°C.

[0099] It is understandable that the present application also needs to meet the third condition and the fourth condition at the same time. By judging whether to enter the defrost process through more conditions, the timing of the defrost operation can be determined more accurately, effectively avoiding the situation of mistaken defrosting.

[0100] S105: If the defrost entry condition is met, the heat pump air conditioner is controlled to enter the defrost operation, and the defrost time of the defrost operation is obtained.

[0101] In the embodiment of the present application, after determining that the defrost entry condition is met, the heat pump air conditioner is controlled to perform a defrost operation, and the defrost time of the defrost operation is recorded. The defrost time of the defrost operation in the embodiment of the present application can be determined by the time from when the four-way valve is powered off to when the defrost exit condition is met.

[0102] S106: When the frost layer thickness and / or the defrost time of the defrost operation reaches a defrost exit condition, exit the defrost operation.

[0103] The present application does not limit the specific content of the defrost exit condition. As an example, the defrost exit condition includes any one of the following a, b, and c:

[0104] a: The frost layer thickness is lower than the preset thickness threshold.

[0105] It is understandable that the present application can pre-set a preset thickness threshold, and by monitoring the frost layer thickness, when the frost layer thickness is lower than the preset thickness threshold, the defrost operation can be exited. It is understandable that the present application does not limit the specific value of the preset thickness threshold, and the preset thickness threshold can be set according to actual needs.

[0106] As an example, the present application can also set a preset percentage of the frost layer thickness below a preset thickness threshold before exiting the defrosting operation, more effectively ensuring thorough defrosting. The present application does not limit the specific value of the preset percentage, which can be 75% as an example.

[0107] b: The defrost time of the defrost operation reaches the preset defrost time.

[0108] In the embodiment of the present application, a preset defrost time can be set in advance, and when it is determined that the defrost time of the defrost operation reaches the preset defrost time, the defrost operation can be exited.

[0109] c: When the supply air temperature is greater than or equal to the sixth temperature threshold, the sum of the evaporation temperature and the supply air temperature is less than the seventh temperature threshold; or, when the supply air temperature is less than the sixth temperature threshold, the evaporation temperature is less than the eighth temperature threshold.

[0110] It is understandable that the present application can also obtain the air supply temperature, which indicates the air temperature delivered by the air conditioning unit into the room or the compartment. The specific values ​​of the sixth temperature threshold, the seventh temperature threshold and the eighth temperature threshold are not limited. As an example, the sixth temperature threshold may be 12°C, the seventh temperature threshold may be 0°C, and the eighth temperature threshold may be -2°C.

[0111] As a possible implementation, when condition c is used as the exit condition, the duration of the condition also needs to meet a preset duration. As an example, the preset duration may be 6 seconds.

[0112] As a possible implementation manner, the defrost exit condition may also include the following d.

[0113] d: Inverter power current protection occurs.

[0114] It is understandable that the present application sets a variety of defrost exit conditions, including the above four a, b, c, d, and only needs to meet any one of the above conditions to exit the defrost operation, which can effectively reduce the situation where the defrost time is too long. Of course, the present application can also exit the defrost operation when multiple of the above a, b, c, d are met.

[0115] Through the above method, the thickness of the frost layer can be determined, and the entry time of the defrost operation can be determined by combining the frost layer thickness with better data such as ambient temperature, air humidity, compressor suction pressure, etc., so as to realize the judgment of the optimal defrost control point and effectively avoid the situation of false defrosting.

[0116] As a possible implementation, a heat pump air conditioner defrosting control method provided in the present application further includes the following steps A1-A2:

[0117] A1: Determine the actual defrost time of the defrost operation.

[0118] It is understandable that the present application can determine the actual defrost time of the defrost operation by determining the time from when the four-way valve is powered off to when the defrost exit condition is met. In the present application, the actual defrost can be accumulated when the evaporator temperature is ≤-2°C in the heating mode and the compressor is turned on in the non-defrosting state. The compressor is stopped and the defrosting is not completed normally, so as to effectively avoid the phenomenon of frost not being removed.

[0119] A2: Update the preset defrost time based on the actual defrost time.

[0120] After determining the actual defrost time, the preset defrost time may also be updated. The present application does not limit the specific manner of updating the preset defrost time based on the actual defrost time. As an example, the present application updates the preset defrost time based on the actual defrost time, including:

[0121] A21: Determine whether the actual defrost time is within the percentage range of the preset defrost time.

[0122] It is understandable that, in the present application, the actual defrost time may be divided by the preset defrost time to obtain a percentage interval of the actual defrost time within the preset defrost time.

[0123] A22: Update the preset defrost time based on the percentage interval.

[0124] The present application does not limit the specific method of updating the preset defrost time based on the percentage interval. As an example, the present application can pre-establish a correspondence between the percentage interval of the actual defrost time and the adjustment coefficient, so that after obtaining the percentage interval, the adjustment coefficient can be determined based on the percentage interval and the correspondence, and the preset defrost time can be updated based on the adjustment coefficient.

[0125] See also Figure 3 , Figure 3A schematic diagram of an actual defrost time in a percentage interval of a preset defrost time provided in an embodiment of the present application. It can be understood that if the actual defrost time is in an interval less than 75% of the preset defrost time, it means that the actual defrost time is in a suboptimal area, and the adjustment coefficient corresponding to this interval is (1-20%). If the actual defrost time is in the area of ​​75%~100% of the preset defrost time, it is in the optimal area, and the adjustment coefficient corresponding to the optimal area is 1, which can also indicate that there is no adjustment coefficient. If the actual defrost time is in the area of ​​100~200% of the preset defrost time, it is in an over-optimal area, and the adjustment coefficient of the over-optimal area is (1+20%); if the actual defrost time is in an area greater than 200% of the preset defrost time, the adjustment coefficient of this area is (1+60%).

[0126] See also Figure 4 , Figure 4 A schematic diagram of a process for updating a preset defrost time is provided for an embodiment of the present application. After defrosting is completed, the present application can update the preset defrost time by determining the actual defrost time, so as to determine the next defrost based on the updated preset defrost time. Figure 4 Tr represents the actual defrost time, Ts represents the preset defrost time, and Ts(n-1) represents the last preset defrost time.

[0127] It can be understood that, assuming that the actual defrost time for the nth time is 40 minutes, the preset defrost time is 60 minutes, and the preset defrost time changes during the entire defrost cycle, the actual defrost time is 66% < 75% of the preset defrost time, then the N+1 preset defrost time is the calculated value multiplied by the adjustment coefficient (1-20%).

[0128] For example, the actual defrost time for the nth time is 50 minutes, and the preset defrost time is 60 minutes (this value changes during the entire defrost cycle). At this time, the actual defrost time is 83% of the preset defrost time. If it is between 75% and 100%, the preset defrost time for N+1 is the calculated value without adjustment coefficient.

[0129] For example, the actual defrost time for the nth time is 80 minutes, and the preset defrost time is 60 minutes (this value changes during the entire defrost cycle). At this time, the actual defrost time is 133% of the preset defrost time, which is between (100~200%). Then the N+1 preset defrost time is the calculated value multiplied by the adjustment coefficient (1+20%).

[0130] For example, the actual defrost time for the nth time is 90 minutes, and the preset defrost time is 40 minutes (this value changes during the entire defrost cycle). At this time, the actual defrost time is 225% of the preset defrost time, which is greater than 200%. Then the N+1 preset defrost time is the calculated value multiplied by the adjustment coefficient (1+60%).

[0131] By updating the preset defrost time, you can effectively avoid situations where the defrost time is too long or the defrost is incomplete, avoid the reduction in the heating capacity of the heat pump air conditioner, the loss of heating capacity, and the reduction in energy efficiency, and improve the user experience of using the heat pump air conditioner.

[0132] As a possible implementation method, a heat pump air conditioner defrost control method provided in the present application also includes: obtaining the return air temperature, and judging whether the defrost entry conditions are met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporating temperature and the compressor suction pressure, including: judging whether the defrost entry conditions are met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporating temperature, the compressor suction pressure and the return air temperature.

[0133] It is understandable that the present application will also obtain the return air temperature of the heat pump air conditioner, and judge whether the defrost entry conditions are met in combination with the return air temperature. It is understandable that the present application can judge whether the fifth condition is met based on the return air temperature when judging whether the defrost entry conditions are met based on the frost layer thickness, ambient temperature, fin temperature, the evaporation temperature and compressor suction pressure. The fifth condition is: the return air temperature is greater than or equal to the ninth temperature threshold. The present application does not limit the specific value of the ninth temperature threshold. As an example, the ninth temperature threshold can be 15°C.

[0134] It is understandable that when the above-mentioned defrost entry conditions are met based on the frost layer thickness, ambient temperature, fin temperature, evaporating temperature and compressor suction pressure, it is also necessary to determine whether the return air temperature meets the fifth condition, and then determine that the defrost entry conditions are met.

[0135] By combining the return air temperature, more data can be used to more accurately determine the timing of the defrost operation, effectively avoiding the situation of false defrosting.

[0136] As a possible implementation, a heat pump air conditioner defrosting control method provided by the present application further includes: further including: obtaining the working time of the compressor, and the interval time between the time of entering the defrosting operation and the last defrosting operation;

[0137] Whether the defrost entry conditions are met is judged based on the frost layer thickness, ambient temperature, fin temperature, evaporating temperature and the compressor suction pressure, including: judging whether the defrost entry conditions are met based on the working time, the interval time, the frost layer thickness, the ambient temperature, the fin temperature, the evaporating temperature and the compressor suction pressure.

[0138] It is understandable that, in the present application, in addition to judging whether the defrost entry condition is met based on the frost layer thickness, ambient temperature, fin temperature, the evaporation temperature and compressor suction pressure, the sixth condition is also judged based on the compressor working time and the interval time of the last defrost operation. The sixth condition is: the compressor working time meets the first preset time length, and the time between the time of entering the defrost operation and the interval time of the last defrost operation meets the second preset time length.

[0139] The present application does not limit the specific values ​​of the first preset time length and the second preset time length. As an example, the first preset time length and the second preset time length may both be 5 minutes.

[0140] It can be understood that the time to enter the defrost operation is when the defrost entry conditions are met based on the frost layer thickness, ambient temperature, fin temperature, evaporating temperature and compressor suction pressure. It is also necessary to determine the working time of the compressor, and the interval time between the time to enter the defrost operation and the last defrost operation meets the sixth condition, then it is determined that the defrost entry conditions are met.

[0141] By combining the working time of the compressor, as well as the interval between the time of entering the defrost operation and the last defrost operation, more data can be used to more accurately determine the timing of the defrost operation and effectively avoid false defrosting.

[0142] As a possible implementation, the present application can control the heat pump air conditioner to enter the defrost operation when the first condition, the second condition, the third condition, the fourth condition, the fifth condition and the sixth condition are met at the same time. The timing of the defrost operation can be more accurately determined by combining more data, effectively avoiding the situation of false defrosting.

[0143] This application does not limit the operating status of each component of the heat pump air conditioner during the defrosting stage. As an example, see Figure 5 , Figure 5A schematic diagram of the operating status of each component of a heat pump air conditioner in the defrost stage provided by an embodiment of the present application. Among them, when the compressor meets the defrost condition, the operating frequency of the compressor runs at 30 HZ for 20 seconds, and then increases to 70 HZ; when the defrost exit condition is met, the compressor operating frequency is adjusted to 30 HZ, runs for 10 seconds, and then increases to 50 HZ, runs for 60 seconds, and then enters automatic adjustment. The indoor fan is always in operation. Outdoor fan: When the defrost condition is met, the outdoor fan runs (ON) for 15 seconds and then stops (OFF); when the defrost exit condition is met, it is turned on (ON) after 10 seconds. Four-way reversing valve: When the defrost condition is met, it loses power "OFF" after 15 seconds of timing, and is powered on (ON) after 10 seconds of timing when the defrost exit condition is met. Liquid circuit solenoid valve: When the defrost condition is met, the liquid circuit solenoid valve is powered (ON) after 16 seconds of timing; when the defrost exit condition is met, it loses power (OFF) after 11 seconds of timing. Expansion valve (EXV): When the defrost condition is met, the opening of EXV is set to 70% after 16 seconds; when the defrost exit condition is met, EXV is the initial heating opening, which lasts for 40 seconds and then automatically adjusts. Electric heating: When the defrost condition is met, it is turned off for 20 seconds and then turned on; when the defrost exit condition is met, the electric heating is turned off. It is understandable that the operating time of the above components and the related operating frequency, opening and other information are only examples, and this application is not limited to this.

[0144] See also Figure 6 , Figure 6 A logic diagram of a heat pump air conditioner defrosting control method provided in an embodiment of the present application. In the present application, the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the suction pressure of the compressor can be obtained by the controller. Through the above data, the thickness of the frost layer is first sensed, that is, the thickness of the frost layer is obtained by the calculation recorded above, and the present application can monitor the growth of the frost layer through real-time calculation, that is, monitor the change of the thickness of the frost layer. By combining the thickness of the frost layer, the ambient temperature, the fin temperature, the evaporation temperature and the suction pressure of the compressor, it is judged whether the defrost entry conditions are met, and by combining multiple conditions to judge, it is realized to enter the defrost operation at the optimal defrost control point, and when the frost layer thickness and / or the defrost time of the defrost operation reach the defrost exit conditions, the defrost operation is exited.

[0145] See also Figure 7 , Figure 7 A schematic diagram of the structure of a heat pump air conditioner defrost control device provided in an embodiment of the present application, the device includes: an acquisition unit 701, a determination unit 702, a calculation unit 703, a judgment unit 704, an entry unit 705, and an exit unit 706.

[0146] The acquisition unit 701 is used to acquire the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the suction pressure of the compressor;

[0147] A determination unit 702, configured to determine a temperature difference between two ends of the evaporator according to the ambient temperature and the fin temperature;

[0148] A calculation unit 703, configured to calculate the thickness of the frost layer according to the temperature difference between the two ends of the evaporator, the frosting time and the air humidity;

[0149] A judgment unit 704 is used to judge whether a defrost entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure;

[0150] Entering unit 705, for controlling the heat pump air conditioner to enter a defrost operation if a defrost entry condition is met, and obtaining a defrost time of the defrost operation;

[0151] The exit unit 706 is used to exit the defrost operation when the frost layer thickness and / or the defrost time of the defrost operation reaches a defrost exit condition.

[0152] As a possible implementation, the acquisition unit 701 is further configured to acquire the working time of the compressor and the working frequency of the compressor.

[0153] The judgment unit 704 is specifically configured to determine that the defrost entry condition is met if the first condition and the second condition are met:

[0154] The first condition includes: the ambient temperature is in a first preset temperature interval, and the first difference between the ambient temperature and the fin temperature is greater than or equal to a first temperature threshold, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to a second temperature threshold, and the frost layer thickness is greater than or equal to a frost layer thickness setting value; or, the ambient temperature is in a second preset temperature interval, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to a third temperature threshold, and the frost layer thickness is greater than or equal to a frost layer thickness setting value;

[0155] The second condition includes: the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working time of the compressor meets the defrost time condition; the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working frequency of the compressor meets the preset working frequency threshold condition and reaches the preset working time.

[0156] As a possible implementation, the judgment unit 704 is specifically configured to: if it is determined that the first condition, the second condition, the third condition and the fourth condition are met, then determine that the defrost entry condition is met; wherein the third condition includes: the fin temperature is less than or equal to a fourth temperature threshold;

[0157] The fourth condition includes: the ambient temperature is less than or equal to a fifth temperature threshold.

[0158] As a possible implementation, the acquisition unit is further used to acquire the supply air temperature;

[0159] The defrost exit condition includes any one of the following:

[0160] The frost layer thickness is lower than the preset thickness threshold;

[0161] The defrost time of the defrost operation reaches the preset defrost time;

[0162] When the supply air temperature is greater than or equal to a sixth temperature threshold, the sum of the evaporation temperature and the supply air temperature is less than a seventh temperature threshold; or, when the supply air temperature is less than the sixth temperature threshold, the evaporation temperature is less than an eighth temperature threshold.

[0163] As a possible implementation manner, the device further includes:

[0164] The determining unit 701 is also used to determine the actual defrosting time of the defrosting operation;

[0165] An updating unit is used to update the preset defrost time based on the actual defrost time.

[0166] As a possible implementation, the updating unit is specifically used to determine that the actual defrost time is within a percentage interval of the preset defrost time;

[0167] Based on the percentage interval, the preset defrost time is updated.

[0168] As a possible implementation, the acquisition unit 701 is also used to acquire the return air temperature;

[0169] The judgment unit 704 is used to judge whether the defrost entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature, the compressor suction pressure and the return air temperature.

[0170] As a possible implementation, the acquisition unit 701 is further used to acquire the working time of the compressor and the interval time of the last defrosting operation;

[0171] The judgment unit 704 is further used to judge whether the defrost entry condition is met based on the working time, the interval time, the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure.

[0172] It should be noted that the heat pump air conditioner defrost control device provided in the embodiment of the present application has the technical effects of any of the above embodiments, and the embodiment of the present application will not be described in detail here.

[0173] The present application also provides a heat pump air conditioner defrosting control device, which may include a memory and a processor, wherein a computer program is stored in the memory, and when the processor calls the computer program in the memory, the steps provided in the above embodiment may be implemented. Of course, the terminal may also include various network interfaces, power supplies and other components.

[0174] It should be noted that the heat pump air conditioner defrost control device provided in the embodiment of the present application has the technical effects of any of the above embodiments, and the embodiment of the present application will not be described in detail here.

[0175] The present application also provides a computer-readable storage medium on which a computer program is stored, and when the computer program is executed, the steps provided in the above embodiment can be implemented. The storage medium may include: 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, and other media that can store program codes.

[0176] It should be noted that a computer-readable storage medium provided in an embodiment of the present application has the technical effects of any of the above embodiments, and the embodiments of the present application are not described in detail here.

[0177] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0178] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0179] Specific examples are used herein to illustrate the principles and implementation methods of the present application, and the description of the above embodiments is only used to help understand the method and core ideas of the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A heat pump air conditioner defrosting control method, characterized in that: The method comprises: Obtain the ambient temperature, evaporator frosting time, air humidity, evaporation temperature, evaporator fin temperature, and compressor suction pressure; Acquire the working time of the compressor and the working frequency of the compressor; Determining a temperature difference between two ends of the evaporator according to the ambient temperature and the fin temperature; Calculating the thickness of the frost layer according to the temperature difference between the two ends of the evaporator, the frosting time and the air humidity; Judging whether a defrost entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature, and the compressor suction pressure includes: If the first and second conditions are met, the defrost entry conditions are met: The first condition includes: the ambient temperature is in a first preset temperature interval, and the first difference between the ambient temperature and the fin temperature is greater than or equal to a first temperature threshold, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to a second temperature threshold, and the frost layer thickness is greater than or equal to a frost layer thickness setting value; or, the ambient temperature is in a second preset temperature interval, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to a third temperature threshold, and the frost layer thickness is greater than or equal to the frost layer thickness setting value; the temperature value of the first preset temperature interval is greater than the temperature value of the second preset temperature interval; The second condition includes: the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working time of the compressor meets the defrosting time condition; or, the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working frequency of the compressor meets the preset working frequency threshold condition and reaches the preset working time; If the defrost entry condition is met, the heat pump air conditioner is controlled to enter the defrost operation, and the defrost time of the defrost operation is obtained; When the frost layer thickness and / or the defrost time of the defrost operation reaches a defrost exit condition, the defrost operation is exited.

2. The method according to claim 1, characterized in that If it is determined that the first condition and the second condition are met, then it is determined that the defrost entry condition is met, including: If it is determined that the first condition, the second condition, the third condition and the fourth condition are met, it is determined that the defrost entry condition is met; wherein the third condition includes: the fin temperature is less than or equal to a fourth temperature threshold; The fourth condition includes: the ambient temperature is less than or equal to a fifth temperature threshold.

3. The method according to claim 1, characterized in that The method further comprises: obtaining the air supply temperature of the heat pump air conditioner; The defrost exit condition includes any one of the following: The thickness of the frost layer is lower than a preset thickness threshold; The defrost time of the defrost operation reaches the preset defrost time; When the supply air temperature is greater than or equal to a sixth temperature threshold, the sum of the evaporation temperature and the supply air temperature is less than a seventh temperature threshold; or, when the supply air temperature is less than the sixth temperature threshold, the evaporation temperature is less than an eighth temperature threshold.

4. The method according to claim 3, characterized in that The method further comprises: Determine the actual defrost time of the defrost operation; The preset defrost time is updated based on the actual defrost time.

5. The method according to claim 4, characterized in that The updating of the preset defrost time based on the actual defrost time includes: Determining that the actual defrost time is within a percentage interval of the preset defrost time; Based on the percentage interval, the preset defrost time is updated.

6. The method according to claim 1, characterized in that The method further includes: obtaining the return air temperature of the heat pump air conditioner, and judging whether the defrosting entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure, including: Whether the defrost entry condition is met is determined based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature, the compressor suction pressure and the return air temperature.

7. The method according to claim 1, characterized in that The method further includes: obtaining the working time of the compressor, and the interval time between the time of entering the defrost operation and the last defrost operation; Then, judging whether the defrost entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure includes: Whether a defrost entry condition is met is determined based on the working time, the interval time, the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure.

8. A heat pump air conditioner defrosting control device, characterized in that: The device comprises: An acquisition unit, used for acquiring the ambient temperature, the frosting time of the evaporator, the air humidity, the evaporation temperature, the fin temperature of the evaporator, and the suction pressure of the compressor; a determination unit, configured to determine a temperature difference between two ends of the evaporator according to the ambient temperature and the fin temperature; A calculation unit, used for calculating according to the temperature difference between the two ends of the evaporator, the frosting time and the air humidity to obtain the thickness of the frost layer; a judging unit, configured to judge whether a defrosting entry condition is met based on the frost layer thickness, the ambient temperature, the fin temperature, the evaporation temperature and the compressor suction pressure; The judgment unit is specifically configured to determine that the defrost entry condition is met if the first condition and the second condition are met: The first condition includes: the ambient temperature is in a first preset temperature interval, and the first difference between the ambient temperature and the fin temperature is greater than or equal to a first temperature threshold, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to a second temperature threshold, and the frost layer thickness is greater than or equal to a frost layer thickness setting value; or, the ambient temperature is in a second preset temperature interval, and the second difference between the ambient temperature and the evaporation temperature is greater than or equal to a third temperature threshold, and the frost layer thickness is greater than or equal to a frost layer thickness setting value; the temperature value of the first preset temperature interval is greater than the temperature value of the second preset temperature interval; The second condition includes: the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working time of the compressor meets the defrosting time condition; or, the suction pressure of the compressor meets the preset pressure threshold, and it is determined that the working frequency of the compressor meets the preset working frequency threshold condition and reaches the preset working time; An entry unit, used for controlling the heat pump air conditioner to enter a defrost operation if a defrost entry condition is met, and obtaining a defrost time for the defrost operation; The exit unit is used to exit the defrost operation when the frost layer thickness and / or the defrost time of the defrost operation reaches a defrost exit condition.

9. A heat pump air conditioner defrosting control device, characterized in that: include: Memory for storing computer programs; A processor is used to execute the computer program stored in the memory to implement the steps of the heat pump air conditioner defrosting control method according to any one of claims 1 to 7.

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