Heat storage defrosting control device, control method and computer-readable storage medium

Abstract

The present invention provides a heat storage defrost control device, a control method and a computer-readable storage medium for an air conditioning system, including an outdoor heat exchanger outlet temperature acquisition module; a timing module that counts the duration T when the outdoor heat exchanger outlet temperature is less than a first preset value; a judgment module that judges whether the air conditioning system is operating in a heating mode, whether the heat storage entry condition is satisfied, and whether the defrost entry condition is satisfied; the heat storage entry condition is that the outdoor heat exchanger outlet temperature is less than a second preset value or the duration T is not less than a first duration threshold; the defrost entry condition is that the outdoor heat exchanger outlet temperature is less than a third preset value or the duration T is greater than a second duration threshold; a control module that controls the air conditioning system to enter a heat storage mode when the heat storage entry condition of the air conditioning system is satisfied; and controls the air conditioning system to exit the heat storage mode and enter a defrost mode when the defrost entry condition is satisfied. The present invention enables the indoor unit and the air conditioning piping to increase in temperature and store heat through the heat storage mode, effectively shortening the defrost time.

Description

Technical Field

[0001] The present invention relates to the field of air conditioners, and specifically to a heat storage defrost control device, a control method and a computer-readable storage medium. Background Art

[0002] The defrost experiment test data of multi-connected air conditioners shows that under the same outdoor unit configuration and indoor unit configuration conditions, with the same defrost control program, the defrost time of the long refrigerant pipe is about 13.04%-19.17% shorter than that of the short refrigerant pipe. Analyzing the reasons in depth, due to the large cumulative volume of the long refrigerant pipe, it has a relatively considerable heat storage capacity. The heat stored in the long refrigerant pipe during defrost can melt the frost and provide a considerable heat source. The lack of heat storage defrost program control in the existing defrost control of multi-connected air conditioner systems using the direct switching mode is the main reason for the long defrost time.

[0003] The existing defrost control of multi-connected air conditioner systems generally uses the direct switching mode for defrost and uses special materials for heat storage and heat release for defrost. The defrost time of the direct switching mode is relatively long, and the indoor side cannot supply heat for a long time, resulting in poor comfort. The auxiliary structure of using special materials for heat storage and heat release for defrost has a large volume and a high design cost, making it difficult to be widely promoted in the market on a large scale. Summary of the Invention

[0004] In view of the above problems, the present invention provides a heat storage defrost control device, a control method and a computer-readable storage medium, which can improve the temperature rise and heat storage of the indoor heat exchanger and the refrigerant pipe through a control optimization program, effectively shorten the defrost time, and improve the defrost efficiency.

[0005] The present invention provides a heat storage defrost control device for an air conditioning system, including a temperature acquisition module for real-time acquisition of the temperature at the outlet of the outdoor heat exchanger; a timing module for counting the duration T of the temperature at the outlet of the outdoor heat exchanger being less than a first preset value; a judgment module for judging whether the air conditioning system is operating in the heating mode, judging whether the air conditioning system meets the heat storage entry condition, and judging whether the air conditioning system meets the defrost entry condition; wherein, the heat storage entry condition is: the temperature at the outlet of the outdoor heat exchanger is less than a second preset value or the duration T is not less than a first duration threshold; the defrost entry condition is: whether the temperature at the outlet of the outdoor heat exchanger is less than a third preset value or the duration T is greater than a second duration threshold; the first duration threshold is the preset maximum defrost time, and the second duration threshold is greater than the first duration threshold; the first preset value, the second preset value, and the third preset value decrease in sequence; a control module for controlling the air conditioning system to enter the heat storage mode when the air conditioning system meets the heat storage entry condition; and controlling the air conditioning system to exit the heat storage mode and enter the defrost mode when the air conditioning system meets the defrost entry condition.

[0006] The present invention monitors the temperature at the outlet of the outdoor heat exchanger in real time, and takes different control measures according to the different temperature at the outlet of the outdoor heat exchanger or the duration that the temperature at the outlet of the outdoor heat exchanger is lower than a preset value, and performs defrosting hierarchically, which can improve the heat storage of the air-conditioning system, improve the defrosting efficiency, shorten the defrosting time, and avoid poor indoor comfort caused by long-term defrosting operation.

[0007] In an alternative technical solution of the present invention, the air-conditioning system includes a compressor, an oil separator, a four-way valve, an indoor unit, a throttling element, an outdoor heat exchanger, and a gas-liquid separator that are connected in sequence to form a refrigerant circulation circuit. The indoor unit includes a plurality of sub-indoor units arranged in parallel. Each sub-indoor unit is internally provided with an internal fan and an electronic expansion valve. A temperature acquisition module is provided at the outlet of the outdoor heat exchanger, and the temperature acquisition module is a temperature sensing package at the outlet of the outdoor heat exchanger.

[0008] According to this technical solution, the structure of the air-conditioning system is simple, and the heat storage defrost control device of the present invention can be applied to different air-conditioning systems, with a wide range of applications.

[0009] In an alternative technical solution of the present invention, in the heat storage mode, the wind speed of the internal fan of the sub-indoor unit in the on state is forced to be reduced to the lowest wind speed; the electronic expansion valve of the sub-indoor unit in the off state is controlled to open to a fixed opening degree, and the corresponding internal fan remains closed.

[0010] According to this technical solution, in the heat storage mode, forcing the wind speed of the internal fan of the sub-indoor unit in the on state to be reduced to the lowest wind speed can reduce the heat loss in the sub-indoor unit and improve the heat storage in the sub-indoor unit; controlling the electronic expansion valve of the sub-indoor unit in the off state to open to a fixed opening degree and keeping the corresponding internal fan closed can ensure that high-temperature refrigerant enters the sub-indoor unit for heat storage, improve the heat storage capacity of the air-conditioning system, and during defrosting, the high-temperature refrigerant in both the on state and the off state can flow to the outdoor heat exchanger, improving the defrosting capacity of the outdoor heat exchanger and shortening the defrosting time.

[0011] In an alternative technical solution of the present invention, it further includes an outdoor ambient temperature acquisition module for acquiring the outdoor ambient temperature; a preset module for presetting the longest defrosting time corresponding to different outdoor ambient temperatures; and a control module for determining a first duration threshold according to the mapping relationship between the outdoor ambient temperature and the longest defrosting time.

[0012] According to this technical solution, the longest defrosting time corresponding to different outdoor ambient temperatures is different. Therefore, when performing heat storage and defrosting judgment, the accuracy of the heat storage and defrosting time nodes is improved, heat storage and defrosting are performed in a timely manner, and the user experience is improved; at the same time, it is avoided that frequent heat storage and defrosting or long-term non-execution of heat storage and defrosting result in too thick frost layer, affecting the normal use of the outdoor heat exchanger.

[0013] The present invention further provides a heat storage defrost control method for an air conditioning system, including the following steps: determining whether the air conditioning system is operating in a heating mode; when the air conditioning system is operating in the heating mode, obtaining the outlet temperature of the outdoor heat exchanger in real time; determining whether the outlet temperature of the outdoor heat exchanger is less than a first preset value, and counting the duration T during which the outlet temperature of the outdoor heat exchanger is less than the first preset value; determining whether the air conditioning system meets the heat storage entry condition, and when the air conditioning system meets the heat storage entry condition, controlling the air conditioning system to enter the heat storage mode; determining whether the air conditioning system meets the defrost entry condition, and when the air conditioning system meets the defrost entry condition, controlling the air conditioning system to exit the heat storage mode and enter the defrost mode; wherein, the heat storage entry condition is that the outlet temperature of the outdoor heat exchanger is less than a second preset value or the duration T is not less than a first duration threshold; the defrost entry condition is that the outlet temperature of the outdoor heat exchanger is less than a third preset value or the duration T is greater than a second duration threshold; the first duration threshold is the preset longest defrost time, and the second duration threshold is greater than the first duration threshold; the first preset value, the second preset value, and the third preset value decrease in sequence.

[0014] In an alternative technical solution of the present invention, the first preset value is 0°C, the first preset value is -9°C, and the third preset value is -12°C.

[0015] According to this technical solution, when the outlet temperature of the outdoor heat exchanger is lower than 0°C, timing starts, and heat storage begins when the outlet temperature of the outdoor heat exchanger is lower than -9°C to store heat for subsequent defrosting. When the outlet temperature of the outdoor heat exchanger is lower than -12°C, the defrosting program is executed. By real-time monitoring the outlet temperature of the outdoor heat exchanger and controlling the defrosting program to be executed when the outlet temperature of the outdoor heat exchanger is lower than the specified value and lasts for the specified time according to the duration counted by the timing module or the outlet temperature of the outdoor heat exchanger, it is possible to avoid too long frosting time, resulting in thick frost layer and extended defrosting time.

[0016] In an alternative technical solution of the present invention, the air conditioning system includes a compressor, an oil separator, a four-way valve, an indoor unit, a throttling element, an outdoor heat exchanger, and a gas-liquid separator that are connected in sequence to form a refrigerant circulation loop. The indoor unit includes a plurality of sub-indoor units arranged in parallel, each sub-indoor unit is correspondingly provided with an indoor fan, and an outdoor heat exchanger outlet temperature sensor is provided at the outlet of the outdoor heat exchanger.

[0017] In an alternative technical solution of the present invention, in the heat storage mode, the control module controls to send an instruction to the indoor unit: forcibly reducing the air volume of the indoor fan of the sub-indoor unit in the on state to the lowest air volume; opening the electronic expansion valve of the sub-indoor unit in the off state to a fixed opening degree, and the corresponding indoor fan remains closed.

[0018] In an alternative technical solution of the present invention, it further includes: obtaining the outdoor ambient temperature; presetting the longest defrost time corresponding to different outdoor ambient temperatures; and determining the first duration threshold according to the mapping relationship between the outdoor ambient temperature and the longest defrost time.

[0019] The present invention further provides a computer-readable storage medium, including a memory storing a computer program, and the computer program executes the above-mentioned heat storage defrosting control method. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of the heat storage defrosting control device in the embodiment of the present invention.

[0021] Figure 2 It is a schematic structural diagram of the air-conditioning system in the embodiment of the present invention.

[0022] Figure 3 It is a schematic flowchart of the heat storage defrosting control method in the embodiment of the present invention.

[0023] Reference Signs:

[0024] Temperature acquisition module 1; timing module 2; judgment module 3; control module 4; compressor 51, oil separator 52, four-way valve 53, sub-indoor unit 54, throttling element 55, outdoor heat exchanger 56, gas-liquid separator 57; check valve 58; oil return capillary 59; outdoor ambient temperature acquisition module 6; preset module 7. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0026] Please refer to Figure 1 As shown, the present invention provides a heat storage defrosting control device for an air-conditioning system, including a temperature acquisition module 1 for real-time acquisition of the temperature T1 at the outlet of the outdoor heat exchanger; a timing module 2 for counting the duration T of the temperature T1 at the outlet of the outdoor heat exchanger being less than a first preset value; a judgment module 3 for judging whether the air-conditioning system is operating in a heating mode, judging whether the air-conditioning system meets the heat storage entry condition, and judging whether the air-conditioning system meets the defrosting entry condition; wherein, the heat storage entry condition is: the temperature T1 at the outlet of the outdoor heat exchanger is less than a second preset value or the duration T is not less than a first duration threshold; the defrosting entry condition is: whether the temperature T1 at the outlet of the outdoor heat exchanger is less than a third preset value or the duration T is greater than a second duration threshold; the first duration threshold is a preset maximum defrosting time, and the second duration threshold is greater than the first duration threshold; the first preset value, the second preset value, and the third preset value decrease in sequence; a control module 4 for controlling the air-conditioning system to enter the heat storage mode when the air-conditioning system meets the heat storage entry condition; and controlling the air-conditioning system to exit the heat storage mode and enter the defrosting mode when the air-conditioning system meets the defrosting entry condition.

[0027] The present invention monitors the temperature T1 at the outlet of the outdoor heat exchanger in real time, and takes different control measures according to the difference of the temperature T1 at the outlet of the outdoor heat exchanger or the duration that the temperature T1 at the outlet of the outdoor heat exchanger is lower than a preset value, and performs defrosting hierarchically, which can improve the heat storage of the air-conditioning system, improve the defrosting efficiency, shorten the defrosting time, and avoid poor indoor comfort caused by long-term defrosting operation.

[0028] In a preferred embodiment of the present invention, as Figure 2 shown, the air-conditioning system includes a compressor 51, an oil separator 52, a four-way valve 53, an indoor unit, a throttling element 55, an outdoor heat exchanger 56, and a gas-liquid separator 57 that are connected in sequence to form a refrigerant circulation circuit. The indoor unit includes a plurality of sub-indoor units 54 arranged in parallel. Each sub-indoor unit 54 is internally provided with an internal fan (not shown in the figure) and an electronic expansion valve (not shown in the figure). A temperature acquisition module 1 is provided at the outlet of the outdoor heat exchanger 56, and the temperature acquisition module 1 is a temperature sensing bulb at the outlet of the outdoor heat exchanger. Further, a check valve 58 and an oil return capillary 59 are further included. The check valve 58 is connected in parallel on both sides of the throttling element 55. The check valve 58 is conductive during refrigeration and non-conductive during heating. Both ends of the oil return capillary 59 are respectively communicated with the suction port of the compressor 51 and the outlet of the oil separator 52. In the embodiment of the present invention, the structure of the air-conditioning system is simple, and the heat storage defrosting control device of the present invention can be applied to different air-conditioning systems, and has a wide application range.

[0029] In a preferred embodiment of the present invention, in the heat storage mode, the air volume of the internal fan of the sub-indoor unit 54 in the on state is forced to be reduced to the lowest air volume; the electronic expansion valve of the sub-indoor unit 54 in the off state is controlled to be opened to a fixed opening degree, and the corresponding internal fan remains closed.

[0030] By the above method, in the heat storage mode, forcing the air volume of the internal fan of the sub-indoor unit in the on state to be reduced to the lowest air volume can reduce the heat loss in the sub-indoor unit and improve the heat storage in the sub-indoor unit; controlling the electronic expansion valve of the sub-indoor unit in the off state to be opened to a fixed opening degree and keeping the corresponding internal fan closed can ensure that high-temperature refrigerant enters the sub-indoor unit for heat storage, improve the heat storage capacity of the air-conditioning system, and during defrosting, the high-temperature refrigerant in the sub-indoor units 54 in the on state and the off state can flow to the outdoor heat exchanger 56, improve the defrosting capacity of the outdoor heat exchanger 56, and shorten the defrosting time.

[0031] In a preferred embodiment of the present invention, it further includes an outdoor ambient temperature acquisition module 6 for acquiring the outdoor ambient temperature; a preset module 7 for presetting the longest defrosting time / first duration threshold corresponding to different outdoor ambient temperatures; and a control module 4 for determining the first duration threshold according to the mapping relationship between the outdoor ambient temperature and the longest defrosting time / first duration threshold.

[0032] In the above manner, the longest defrosting time corresponding to different outdoor ambient temperatures is different. Thus, when performing heat storage and defrosting judgment, the accuracy of the time nodes for entering heat storage and defrosting is improved, heat storage and defrosting are carried out in a timely manner, and the user experience is enhanced. At the same time, frequent heat storage and defrosting or long-term non-execution of heat storage and defrosting are avoided, which may cause excessive frost layer and affect the normal use of the outdoor heat exchanger 56.

[0033] Please refer to Figure 3 As shown in the figure, the present invention further provides a heat storage and defrosting control method for an air conditioning system, including the following steps:

[0034] S101: When it is detected that the compressor 51 is running, enter S102;

[0035] S102: Determine whether the air conditioning system is operating in the heating mode; if it is in the heating mode, enter the operation of S103. If it is in the cooling mode, return to the operation of S101.

[0036] S103: When the air conditioning system is operating in the heating mode, obtain the outlet temperature T1 of the outdoor heat exchanger in real time; determine whether the outlet temperature T1 of the outdoor heat exchanger is less than the first preset value. If it is satisfied, enter the operation of S104. Otherwise, return to the operation of S102.

[0037] S104: Count the duration T during which the outlet temperature T1 of the outdoor heat exchanger is less than the first preset value; enter S105;

[0038] S105: Determine whether the air conditioning system meets the heat storage entry condition. When the air conditioning system meets the heat storage entry condition, control the air conditioning system to enter the heat storage mode; the heat storage entry condition is: the outlet temperature T1 of the outdoor heat exchanger is less than the second preset value or the duration T is not less than the first duration threshold; if it is satisfied, enter the operation of S106. Otherwise, return to the operation of S104.

[0039] S106: The control module 4 controls to send an instruction to the indoor unit: force the air damper of the internal fan of the sub-indoor unit in the on state to be reduced to the lowest air damper; control the electronic expansion valve of the sub-indoor unit in the off state to be opened to a fixed opening degree, and the corresponding internal fan remains closed.

[0040] S107: Determine whether the air conditioning system meets the defrosting entry condition. When the air conditioning system meets the defrosting entry condition, control the air conditioning system to exit the heat storage mode and enter the defrosting mode, and the indoor unit is controlled according to the defrosting instruction; the defrosting entry condition is: whether the outlet temperature T1 of the outdoor heat exchanger is less than the third preset value or the duration T is greater than the second duration threshold;

[0041] Among them, the first duration threshold is the preset longest defrosting time, the second duration threshold is greater than the first duration threshold; the first preset value, the second preset value, and the third preset value decrease in sequence.

[0042] In a preferred embodiment of the present invention, the first preset value is 0 °C, the second preset value is -9 °C, and the third preset value is -12 °C. When the outlet temperature T1 of the outdoor heat exchanger is lower than 0 °C, timing starts, and when the outlet temperature T1 of the outdoor heat exchanger is lower than -9 °C, heat storage begins to store heat for defrosting later. When the outlet temperature T1 of the outdoor heat exchanger is lower than -12 °C, the defrosting program is executed. By monitoring the outlet temperature T1 of the outdoor heat exchanger in real time and controlling the defrosting program to be executed when the outlet temperature T1 of the outdoor heat exchanger is lower than the specified value and lasts for a specified time according to the duration counted by the timing module 2 or the outlet temperature T1 of the outdoor heat exchanger, it is possible to avoid too long frosting time, resulting in a thick frost layer, extending the defrosting time, thereby improving the defrosting efficiency, shortening the defrosting time, and reducing the defrosting difficulty.

[0043] In a preferred embodiment of the present invention, it further includes step S108: obtaining the outdoor ambient temperature; presetting the maximum defrosting time corresponding to different outdoor ambient temperatures; and determining the first duration threshold according to the mapping relationship between the outdoor ambient temperature and the maximum defrosting time. The order of S108 can be adjusted as needed. Preferably, it is located before step S101.

[0044] In a preferred embodiment of the present invention, the second duration threshold = the first duration threshold + 300 s, that is, when it is detected that the operation time of the heat storage mode reaches 5 min, the defrosting program is entered, which can ensure the stored heat and control the thickness of the frost layer, so that the air-conditioning system generates more heat and defrosts quickly.

[0045] As an example, the multi-connected air-conditioning system operates in the heating mode at an ambient temperature of 2 °C. The t value of the 2 °C ambient temperature, that is, the maximum defrosting time set by the main control program, is 75 min. When T1 < 0 °C, the system enters the defrosting time accumulation, and the timing module 2 starts. When any of the following conditions is met: Condition 1: The outlet temperature T1 of the outdoor heat exchanger is detected in real time and the following judgment is made: T1 < -9 °C? Condition 2: The duration T counted by the timing module 2 ≥ t? The air-conditioning system enters the heat storage mode, and the control module 4 issues the following instructions to the indoor unit: Forcefully reduce the air volume of the internal fan of the sub-indoor unit 54 in the on state to the lowest air volume; Open the electronic expansion valve of the sub-indoor unit 54 in the off state to a fixed opening, and the corresponding internal fan remains closed. When any of the following conditions is met: Condition 1: The outlet temperature T1 of the outdoor heat exchanger is detected in real time and the following judgment is made: T1 < -12 °C? Condition 2: The duration T counted by the timing module 2 ≥ t + 300S? The air-conditioning system exits the heat storage mode and enters the normal defrosting mode. The embodiment of the present invention makes the indoor unit and the air-conditioning piping warm up and store heat by means of the heat storage mode, which can effectively shorten the defrosting time.

[0046] The present invention further provides a computer-readable storage medium, including a memory storing a computer program, and the computer program executes the above-mentioned heat storage defrosting control method.

[0047] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A heat storage defrosting control device for an air conditioning system, characterized in that, including a temperature acquisition module for acquiring the outlet temperature of the outdoor heat exchanger in real time; a timing module for counting the duration T during which the outlet temperature of the outdoor heat exchanger is less than a first preset value; a judgment module for judging whether the air-conditioning system is operating in a heating mode, judging whether the air-conditioning system meets the heat storage entry condition, and judging whether the air-conditioning system meets the defrosting entry condition; wherein, the heat storage entry condition is: the outlet temperature of the outdoor heat exchanger is less than a second preset value or the duration T is not less than a first duration threshold; the defrosting entry condition is: whether the outlet temperature of the outdoor heat exchanger is less than a third preset value or the duration T is greater than a second duration threshold; the first duration threshold is the preset longest defrosting time, and the second duration threshold is greater than the first duration threshold; the first preset value, the second preset value, and the third preset value decrease in sequence; a control module for controlling the air-conditioning system to enter the heat storage mode when the air-conditioning system meets the heat storage entry condition; and for controlling the air-conditioning system to exit the heat storage mode and enter the defrosting mode when the air-conditioning system meets the defrosting entry condition; the air-conditioning system includes a compressor, an oil separator, a four-way valve, an indoor unit, a throttling element, an outdoor heat exchanger, and a gas-liquid separator that are connected in sequence to form a refrigerant circulation loop. The indoor unit includes a plurality of sub-indoor units connected in parallel. Each sub-indoor unit is internally provided with an internal fan and an electronic expansion valve. The temperature acquisition module is provided at the outlet of the outdoor heat exchanger, and the temperature acquisition module is a temperature sensing bulb at the outlet of the outdoor heat exchanger; in the heat storage mode, the control module controls to send an instruction to the indoor unit: forcibly reducing the air damper of the internal fan of the sub-indoor unit in the on state to the lowest air damper; controlling the electronic expansion valve of the sub-indoor unit in the off state to open to a fixed opening degree, and the corresponding internal fan remains closed.

2. The heat storage defrosting control device for the air conditioning system according to claim 1, wherein It further includes an outdoor ambient temperature acquisition module for acquiring the outdoor ambient temperature; a preset module for presetting the longest defrosting time corresponding to different outdoor ambient temperatures; and the control module determines the first duration threshold according to the mapping relationship between the outdoor ambient temperature and the longest defrosting time.

3. A heat storage defrosting control method for an air conditioning system, characterized in that, including the following steps: judging whether the air-conditioning system is operating in a heating mode; when the air-conditioning system is operating in a heating mode, acquiring the outlet temperature of the outdoor heat exchanger in real time; judging whether the outlet temperature of the outdoor heat exchanger is less than a first preset value, and counting the duration T during which the outlet temperature of the outdoor heat exchanger is less than the first preset value; judging whether the air-conditioning system meets the heat storage entry condition, and controlling the air-conditioning system to enter the heat storage mode when the air-conditioning system meets the heat storage entry condition; judging whether the air-conditioning system meets the defrosting entry condition, and controlling the air-conditioning system to exit the heat storage mode and enter the defrosting mode when the air-conditioning system meets the defrosting entry condition; wherein, the heat storage entry condition is: the outlet temperature of the outdoor heat exchanger is less than a second preset value or the duration T is not less than a first duration threshold; the defrosting entry condition is: whether the outlet temperature of the outdoor heat exchanger is less than a third preset value or the duration T is greater than a second duration threshold; The first duration threshold is a preset maximum defrosting time, and the second duration threshold is greater than the first duration threshold; the first preset value, the second preset value, and the third preset value decrease in sequence; The air conditioning system includes a compressor, an oil separator, a four-way valve, an indoor unit, a throttling element, an outdoor heat exchanger, and a gas-liquid separator that are connected in sequence to form a refrigerant circulation loop. The indoor unit includes a plurality of sub-indoor units arranged in parallel. Each sub-indoor unit is internally provided with an internal blower and an electronic expansion valve. A temperature acquisition module is provided at the outlet of the outdoor heat exchanger, and the temperature acquisition module is a temperature sensing bulb at the outlet of the outdoor heat exchanger; In the heat storage mode, the control module controls to send an instruction to the indoor unit: forcibly reduce the air volume of the internal blower of the sub-indoor unit in the on state to the lowest air volume; control the electronic expansion valve of the sub-indoor unit in the off state to open to a fixed opening degree, and the corresponding internal blower remains closed.

4. The heat storage defrosting control method of the air conditioning system according to claim 3, characterized in that, The first preset value is 0 °C, the second preset value is -9 °C, and the third preset value is -12 °C.

5. The defrosting control method with heat storage for the air conditioning system according to claim 3, characterized in that, It further includes: obtaining the outdoor ambient temperature; The maximum defrosting time corresponding to different outdoor ambient temperatures is preset; Determine the first duration threshold according to the mapping relationship between the outdoor ambient temperature and the maximum defrosting time.

6. A computer-readable storage medium, characterized in that, A memory stores a computer program, and when the computer program is executed, it is the heat storage defrosting control method according to any one of claims 3 to 5.

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