CN115235138B

CN115235138B - Control method of three-pipe air conditioning system, three-pipe air conditioning system and storage medium

Info

Publication number: CN115235138B
Application number: CN202210710029.3A
Authority: CN
Inventors: 梁科琳; 陈磊; 廖振华
Original assignee: GD Midea Air Conditioning Equipment Co Ltd; Midea Group Wuhan HVAC Equipment Co Ltd
Current assignee: GD Midea Air Conditioning Equipment Co Ltd; Midea Group Wuhan HVAC Equipment Co Ltd
Priority date: 2022-06-22
Filing date: 2022-06-22
Publication date: 2023-09-26
Anticipated expiration: 2042-06-22
Also published as: CN115235138A

Abstract

The application discloses a control method of a three-pipe air conditioning system, the three-pipe air conditioning system and a storage medium, wherein the control method of the three-pipe air conditioning system comprises the following steps: in the refrigeration mode, when receiving an oil return signal, adjusting the supercooling throttle valve from the current opening to the initial opening; detecting the exhaust temperature in real time, wherein the exhaust temperature is the temperature of an exhaust port of a compressor; and adjusting the target opening of the supercooling throttle valve according to the exhaust temperature and the initial opening so as to enable lubricating oil in the system to return to the compressor. The application realizes the oil return of the lubricating oil of the compressor.

Description

Control method of three-pipe air conditioning system, three-pipe air conditioning system and storage medium

Technical Field

The application relates to the technical field of intelligent air conditioners, in particular to a control method of a three-pipe air conditioning system, the three-pipe air conditioning system and a storage medium.

Background

With the continuous improvement of the living standard of people, the air conditioning system is installed in the living and indoor working environments to improve the comfort of the living and working environments, so that the air conditioning system becomes an important choice for improving the comfort requirement of people. The three-pipe air conditioning system can cool and heat simultaneously, and can well meet the requirements of users. However, the three-pipe air conditioning system is complex, needs periodic oil return control, and is provided with a third pipe, namely a high-pressure pipe, so that the functional requirement can be met, the reliable operation of the system can be ensured, the refrigerant change amount is large in the oil return process based on the three-pipe air conditioning system in a refrigeration mode, the shutdown is easily caused by faults, and the oil return process is abnormal.

Disclosure of Invention

The application mainly aims to provide a control method of a three-pipe air conditioning system, the three-pipe air conditioning system and a storage medium, and aims to solve the problem of how to improve the abnormal refrigerating and oil returning process of the three-pipe air conditioning system.

In order to achieve the above object, the present application provides a triple-tube air conditioning system, which comprises a first high-pressure tube, a second high-pressure tube, a low-pressure tube and a switching device, wherein the switching device is arranged between an outdoor unit and an indoor unit and is used for controlling the indoor unit to execute a refrigeration mode, a heating mode or a simultaneous refrigeration and heating mode, the switching device comprises a supercooling throttle valve, the supercooling throttle valve is arranged on the low-pressure tube connected with the first high-pressure tube, and one side of the supercooling throttle valve is connected with a plate in a switching way.

In an embodiment, the switching device comprises a capillary tube disposed between the second high pressure tube and the low pressure tube.

In an embodiment, the switching device further comprises a solenoid valve and a check valve connected in series with the capillary tube, the solenoid valve and the check valve being connected in series and disposed between the second high pressure tube and the low pressure tube.

In order to achieve the above object, the present application provides a control method of a three-pipe air conditioning system, the control method of the three-pipe air conditioning system comprising the steps of:

in the refrigeration mode, when receiving an oil return signal, adjusting the supercooling throttle valve from the current opening to the initial opening;

detecting the exhaust temperature in real time, wherein the exhaust temperature is the temperature of an exhaust port of a compressor;

and adjusting the target opening of the supercooling throttle valve according to the exhaust temperature and the initial opening so as to enable lubricating oil in the system to return to the compressor.

In an embodiment, the step of adjusting the target opening degree of the supercooling throttle according to the exhaust temperature and the initial opening degree includes:

if the exhaust temperature is increased at a first speed, determining the target opening according to a preset first opening and a real-time opening, wherein the real-time opening comprises an initial opening;

and if the exhaust temperature is reduced at the second speed, determining the target opening according to a preset second opening and a real-time opening.

In one embodiment, after the step of detecting the exhaust temperature in real time, the method further includes:

and if the exhaust temperature is greater than the preset temperature, adjusting the supercooling throttle valve to the current opening.

In one embodiment, the control method of the three-pipe air conditioning system includes:

detecting an air conditioning mode of the three-pipe air conditioning system after the three-pipe air conditioning system runs for a preset time period;

if the air conditioning mode is a refrigeration mode, opening an electromagnetic valve and a one-way valve which are connected in series with the capillary tube so as to drain the accumulated liquid in the second high-pressure tube into the low-pressure tube.

In an embodiment, the step of opening the solenoid valve corresponding to the capillary tube includes:

and opening the electromagnetic valve and the one-way valve which are connected in series with the capillary tube according to the opening time, wherein the opening time is determined by the pipe diameter and the pipe length of the second high-pressure pipe.

In order to achieve the above object, the present application also provides a triple-control air conditioning system including a memory, a processor, and a control program of the triple-control air conditioning system stored in the memory and executable on the processor, the control program of the triple-control air conditioning system realizing the respective steps of the control method of the triple-control air conditioning system as described above when being executed by the processor.

In order to achieve the above object, the present application also provides a computer-readable storage medium storing a control program of a triple-tube air conditioning system, which when executed by a processor, implements the respective steps of the control method of the triple-tube air conditioning system as described above.

The application provides a control method of a three-pipe air conditioning system, the three-pipe air conditioning system and a storage medium, wherein a supercooling throttle valve is adjusted to an initial opening from a current opening when receiving an oil return signal in a refrigeration mode; detecting the exhaust temperature in real time, wherein the exhaust temperature is the temperature of an exhaust port of the compressor; and adjusting the target opening of the supercooling throttle valve according to the exhaust temperature and the initial opening so as to enable the lubricating oil in the system to return to the compressor. By adjusting the opening of the supercooling throttle valve, oil return of lubricating oil of the compressor is realized under the condition that the exhaust temperature is normal.

Drawings

Fig. 1 is a schematic hardware structure of a three-pipe air conditioning system according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a three-tube air conditioning system according to the present application;

FIG. 3 is a schematic diagram of the refrigerant flow direction in the cooling mode or heating mode of the three-tube air conditioning system of the present application;

FIG. 4 is a schematic diagram of the refrigerant flow direction in the simultaneous cooling and heating mode of the three-tube air conditioning system of the present application;

FIG. 5 is a flow chart of a control method of a three-pipe air conditioning system according to a first embodiment of the present application;

FIG. 6 is a flow chart of a second embodiment of a control method of a triple-tube air conditioning system according to the present application;

fig. 7 is a schematic diagram of the position of a capillary tube in a three-tube air conditioning system according to the present application.

Reference numerals	Name of the name	Reference numerals	Name of the name
				11	First high-pressure pipe	12	Second high-pressure pipe
13	Low pressure pipe	20	Switching device
				21	Supercooling throttle valve	22	Plate changer
23	Capillary tube	24	Electromagnetic valve
				25	One-way valve	30	Outdoor unit
40	Indoor machine

The achievement of the objects, functional features and advantages of the present application will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.

In order that the above-described aspects may be better understood, exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The main solutions of the embodiments of the present application are: in the refrigeration mode, when receiving an oil return signal, adjusting the supercooling throttle valve from the current opening to the initial opening; detecting the exhaust temperature in real time, wherein the exhaust temperature is the temperature of an exhaust port of the compressor; and adjusting the target opening of the supercooling throttle valve according to the exhaust temperature and the initial opening so as to enable the lubricating oil in the system to return to the compressor. By adjusting the opening of the supercooling throttle valve, oil return of lubricating oil of the compressor is realized under the condition that the exhaust temperature is normal.

As one implementation, a triple-tube air conditioning system may be as shown in fig. 1.

The embodiment of the application relates to a three-pipe air conditioning system, which comprises: a processor 101, such as a CPU, a memory 102, and a communication bus 103. Wherein the communication bus 103 is used to enable connected communication among the components.

The memory 102 may be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. As shown in fig. 1, a control program of a triple-tube air conditioning system may be included in a memory 102 as a computer-readable storage medium; and the processor 101 may be configured to invoke the control program of the triple-control air conditioning system stored in the memory 102 and perform the following operations:

In one embodiment, the processor 101 may be configured to invoke a control program of the triple-control air conditioning system stored in the memory 102 and perform the following operations:

Referring to fig. 2, the triple-tube air conditioning system of the present application includes a first high pressure tube 11, a second high pressure tube 12, a low pressure tube 13, and a switching device 20 disposed between an outdoor unit 30 and an indoor unit 40 for controlling the indoor unit 40 to perform a cooling mode, a heating mode, or a simultaneous cooling and heating mode, the switching device 20 includes a supercooling throttle valve 21, the supercooling throttle valve 21 is disposed at the low pressure tube 13 connected to the first high pressure tube 11, and one side of the supercooling throttle valve 21 is connected to a plate switch 22.

Alternatively, the switching device 20 is an MS device, and the switching device 20 is configured to control the plurality of indoor units 40 to perform a cooling mode, a heating mode, or a simultaneous cooling and heating mode. Alternatively, when the three-pipe air conditioning system performs the cooling mode or the heating mode, as shown in fig. 3, the refrigerant flows into the indoor unit from the second high pressure pipe 12 and flows out of the indoor unit from the first high pressure pipe 11 in the heating mode, and the refrigerant flows into the indoor unit 40 from the first high pressure pipe 11 and flows out of the indoor unit from the low pressure pipe 13 in the cooling mode.

Alternatively, in the simultaneous cooling and heating mode, there is a simultaneous cooling mode performed by the indoor unit 40, and the indoor unit 40 performs the heating mode, for example, different air conditioning modes may be performed by the indoor units 40 in different rooms. Alternatively, the three-pipe air conditioning system performs both the cooling and heating modes, as shown in fig. 4, the refrigerant flows into the indoor unit of the cooling mode from the first high pressure pipe 11 and flows out from the low pressure pipe 13; the refrigerant flows into the indoor unit 40 of the heating mode from the second high-pressure pipe 12, and flows out from the low-pressure pipe 13.

In order to allow the refrigerant of the second high-pressure pipe 12 to flow slowly, it is not excessively condensed into a liquid state, and the liquid discharging capability of the capillary tube 23 is not lowered too quickly. Optionally, the switching device 20 comprises a liquid-repellent capillary tube 23, the capillary tube 23 being arranged between the second high-pressure tube 12 and the low-pressure tube 13. Alternatively, the capillary 23 has a length of 600-100 mm and a diameter of phi 3.2 x 1.9. In the pure refrigeration mode, the second high-pressure pipe 12 is at a high-pressure saturation temperature, liquid accumulation can not be continued, the exhaust temperature is stabilized below 80 ℃ and cannot rise, and the refrigeration effect is obviously improved.

Optionally, the switching device 20 further comprises a solenoid valve 24 and a check valve 25 connected in series with the capillary tube 23, the solenoid valve 24 and the check valve 25 being connected in series and being arranged between the second high pressure tube 12 and the low pressure tube 13. Wherein the solenoid valve 24 is an SVP solenoid valve. In the pure refrigeration mode, the electromagnetic valve 24 intermittently opens the liquid discharge, thereby further supplementing the control of insufficient liquid discharge capacity of the capillary tube 23. The oil return operation can not cause system stop and can not refrigerate due to abrupt change of the opening of the valve body under extreme working conditions of the refrigeration system, such as outdoor high temperature and indoor low temperature. Through the regulation and control of the variable supercooling throttle valve, the refrigerant circulation quantity of the main path system is not reduced too much, only 33% is reduced at maximum, and quick oil return is realized.

Based on the hardware architecture of the three-pipe air conditioning system, the embodiment of the control method of the three-pipe air conditioning system is provided.

Referring to fig. 5, fig. 5 is a first embodiment of a control method of a triple-tube air conditioning system according to the present application, the control method of the triple-tube air conditioning system includes the steps of:

step S10, in a refrigeration mode, when receiving an oil return signal, adjusting the supercooling throttle valve from the current opening to the initial opening;

step S20, detecting the exhaust temperature in real time, wherein the exhaust temperature is the temperature of an exhaust port of the compressor;

and step S30, adjusting the target opening degree of the supercooling throttle valve according to the exhaust temperature and the initial opening degree so as to enable the lubricating oil in the system to return to the compressor.

Specifically, after the three-pipe air conditioning system is operated for a certain time, in order to ensure the operation safety of the compressor, the lubricating oil discharged to the three-pipe air conditioning system needs to be circulated back into the compressor, so that the compressor is ensured to have enough lubricating oil lubrication, and therefore, the refrigerating system is required to perform oil return control. After the system is operated for a period of time, the valve body controlled by supercooling is closed after the system is started for 2 hours or continuously operated for 8 hours, the flow rate of the refrigerant in the main pipeline is increased, lubricating oil stored in the internal machine and the pipeline is brought back to the outdoor machine, and oil return operation is carried out for a certain period of time.

When the system carries out high-temperature refrigeration of an outside environment temperature of 52 ℃ and an inside environment temperature of 17 ℃ and a fully-opened internal machine meets the oil return operation requirement, the switching device directly closes the supercooling throttle valve from the current opening after receiving an oil return signal, the flow is suddenly reduced, the exhaust temperature of the compressor is rapidly increased to the protection temperature of 115 ℃, and the system is stopped and cannot refrigerate. The reason why the cooling failure occurs is that when the outside condensation temperature is higher and the inside evaporation temperature is lower, especially when the inside evaporation temperature is close to the lowest set temperature, the throttle valves of the indoor units are closed relatively small, so that the flow rate of the indoor units is small, at the moment, if the supercooling throttle valve is closed suddenly, the flow rate is reduced sharply, and the exhaust temperature is increased until the exhaust temperature is protected at the low flow rate and the high condensation temperature. Statistics data show that after the supercooling throttle valve is closed, the return air pressure gradually decreases from 0.75MPa to 0.49MPa, the flow rate decreases from 0.23Kg/s to 0.104Kg/s, the flow rate decreasing amplitude is up to 65% in 4 minutes, the pressure ratio increases from 4.23 to 6.72, and the return air superheat degree increases from 2 to 17.6.

Based on the above, in the refrigeration mode of the three-pipe air conditioning system, the embodiment adjusts the supercooling throttle valve from the current opening to the initial opening when receiving the oil return signal, wherein the supercooling throttle valve is an EEVA unidirectional electromagnetic valve. Optionally, the initial opening is a minimum opening.

Detecting the exhaust temperature in real time, wherein the exhaust temperature is the temperature of an exhaust port of a compressor; and adjusting the target opening of the supercooling throttle valve according to the exhaust temperature and the initial opening so as to enable lubricating oil in the system to return to the compressor.

Optionally, if the exhaust temperature increases at a first speed, determining a target opening according to a preset first opening and a real-time opening, where the real-time opening includes an initial opening, and the first speed is 5 ℃/30s, the preset first opening is +5pls, and if the real-time opening is the initial opening 5pls, the target opening is 10pls; if the exhaust temperature is cooled at the second speed, determining a target opening according to a preset second opening and a real-time opening, wherein the second speed is 5 ℃/1min, the preset second opening is-5 pls, and if the real-time opening is 10pls, the target opening is 5pls. The real-time opening is the real-time opening of the supercooling throttle valve in the oil return process.

Optionally, if the exhaust temperature is greater than the preset temperature, the supercooling throttle valve is adjusted to the current opening before oil return. The preset temperature is, for example, 110 ℃.

According to the control method in this embodiment, the refrigerant flow path is only reduced by 33%, and compared with the prior art, the refrigerant circulation amount is improved by half, and the exhaust temperature is at most 106 ℃, as shown in the following table:

in the technical scheme of the embodiment, in a refrigeration mode, when receiving an oil return signal, the supercooling throttle valve is adjusted from the current opening to the initial opening; detecting the exhaust temperature in real time, wherein the exhaust temperature is the temperature of an exhaust port of the compressor; and adjusting the target opening of the supercooling throttle valve according to the exhaust temperature and the initial opening so as to enable the lubricating oil in the system to return to the compressor. By adjusting the opening of the supercooling throttle valve, oil return of lubricating oil of the compressor is realized under the condition that the exhaust temperature is normal.

Referring to fig. 6, fig. 6 is a second embodiment of a control method of a triple-tube air conditioning system according to the present application, and based on the first embodiment, the method further includes the steps of:

step S40, detecting an air conditioning mode of the three-pipe air conditioning system after the three-pipe air conditioning system runs for a preset time period;

and S50, if the air conditioning mode is a refrigerating mode, opening an electromagnetic valve and a one-way valve which are connected in series with the capillary tube so as to drain the accumulated liquid in the second high-pressure tube into the low-pressure tube.

Specifically, in order to meet the requirements of simultaneous cooling and heating, a third pipe, namely a second high-pressure pipe, is arranged, the second high-pressure pipe is directly connected with an exhaust pipe of a compressor, a four-way valve is not arranged in the middle, and high-pressure and low-pressure switching cannot be performed, so that a capillary tube for preventing effusion is additionally arranged between the second high-pressure pipe and the low-pressure pipe, as shown by an arrow in fig. 7, and is arranged on the outdoor machine side, at the moment, the diameter of the capillary tube for preventing effusion cannot be too large, the length cannot be too short, otherwise, the problems of poor refrigerating or heating effect of a system, abnormal oil return of the system and the like are easily caused.

In order to realize the functions of partial refrigeration and partial heating of different indoor units of a three-pipe air conditioning system, a switching device is added between the indoor units and the outdoor units, and the switching device is used for switching refrigerants to different indoor units. In the refrigerating process, the switching device is used for setting supercooling control for solving the problem that refrigerant flowing sound, namely high-pressure gas-liquid two-phase refrigerant sent by the outdoor unit is split into a part of refrigerant throttling, and the refrigerant entering the indoor units is cooled into liquid refrigerant as much as possible through plate exchange and heat exchange with the main-path refrigerant, and then enters each indoor unit for evaporation refrigeration. Through tests and analysis, the capillary tube for preventing liquid accumulation between the second high-pressure tube and the low-pressure tube is arranged in the outdoor unit, and the refrigerant of the high-pressure tube is condensed into liquid state when being discharged to the low-pressure tube quickly due to strong heat exchange of the outside fan, so that the refrigerant quantity of the circulating system is reduced, and the refrigerating or heating effect of the system is easily deteriorated.

Based on the above situation, in order to make the high-pressure gas pipe refrigerant flow slowly, the refrigerant is not excessively condensed into liquid state, and the liquid discharging capability of the capillary tube is not reduced too quickly. Optionally, the switching device includes a capillary tube for preventing liquid accumulation, and the capillary tube is disposed between the second high-pressure tube and the low-pressure tube. Optionally, the length of the capillary tube is 600-100 mm, and the diameter of the capillary tube is phi 3.2 x 1.9. In the pure refrigeration mode, the second high-pressure pipe is at a high-pressure saturation temperature, liquid accumulation can not be continued, the exhaust temperature is stabilized below 80 ℃ and cannot rise, and the refrigeration effect is obviously improved.

Optionally, detecting an air conditioning mode of the three-pipe air conditioning system after the three-pipe air conditioning system runs for a preset time period; if the air conditioning mode is a refrigerating mode, the electromagnetic valve and the one-way valve which are connected in series with the capillary tube are opened, so that the accumulated liquid in the second high-pressure tube is discharged into the low-pressure tube, and the defect of insufficient liquid discharging capability of the capillary tube is further overcome.

Optionally, the electromagnetic valve and the one-way valve connected in series with the capillary tube are opened according to the opening time, and the opening time is determined by the pipe diameter and the pipe length of the second high-pressure pipe. Optionally, the opening duration is also affected by the system's bad working conditions and system capacity. Alternatively, the opening duration is generally 2.5 to 3.5 minutes, preferably 3 minutes.

In the technical scheme of the embodiment, after a three-pipe air conditioning system runs for a preset time, detecting an air conditioning mode of the three-pipe air conditioning system; if the air conditioning mode is a refrigeration mode, opening an electromagnetic valve and a one-way valve which are connected in series with the capillary tube so as to drain the accumulated liquid in the second high-pressure tube into the low-pressure tube. The liquid accumulation in the second high-pressure pipe is discharged, the refrigerant quantity in the three-pipe air conditioning system is ensured, and the refrigerating or refrigerating effect of the system is ensured.

The present application also provides a three-tube air conditioning system, which includes a memory, a processor, and a control program of the three-tube air conditioning system stored in the memory and executable on the processor, wherein the control program of the three-tube air conditioning system, when executed by the processor, implements the steps of the control method of the three-tube air conditioning system as described in the above embodiment.

The present application also provides a computer-readable storage medium storing a control program of a triple-tube air conditioning system, which when executed by a processor, implements the steps of the control method of the triple-tube air conditioning system described in the above embodiment.

The foregoing embodiment numbers of the present application are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, system, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, system, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, system, article, or apparatus that comprises the element.

From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment system may be implemented by means of software plus necessary general purpose hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a computer readable storage medium (e.g. ROM/RAM, magnetic disk, optical disk) as described above, comprising instructions for causing a terminal device (which may be a mobile phone, a computer, a parking management device, an air conditioner, or a network device, etc.) to execute the system according to the embodiments of the present application.

The foregoing description is only of the preferred embodiments of the present application, and is not intended to limit the scope of the application, but rather is intended to cover any equivalents of the structures or equivalent processes disclosed herein or in the alternative, which may be employed directly or indirectly in other related arts.

Claims

1. The utility model provides a three control air conditioning system, three control air conditioning system includes first high-pressure pipe, second high-pressure pipe, low pressure pipe and auto-change over device, auto-change over device sets up between off-premises station and indoor set for control indoor set carries out the refrigeration mode, perhaps heats the mode, perhaps refrigerates simultaneously heats the mode, its characterized in that, auto-change over device includes the supercooling choke, the supercooling choke set up in with first high-pressure pipe connection the low pressure pipe, supercooling choke one side is traded with the board and is connected, wherein, three control air conditioning system's control method includes: in the refrigeration mode, when receiving an oil return signal, adjusting the supercooling throttle valve from the current opening to the initial opening; detecting the exhaust temperature in real time, wherein the exhaust temperature is the temperature of an exhaust port of a compressor; if the exhaust temperature is increased at a first speed, determining a target opening according to a preset first opening and a real-time opening, wherein the real-time opening comprises an initial opening; and if the exhaust temperature is reduced at the second speed, determining the target opening according to the preset second opening and the real-time opening so as to enable the lubricating oil in the system to return to the compressor.

2. The triple tube air conditioning system of claim 1 wherein the switching device comprises a capillary tube disposed between the second high pressure tube and the low pressure tube.

3. The triple tube air conditioning system of claim 2 wherein the switching device further comprises a solenoid valve and a one-way valve in parallel with the capillary tube, the solenoid valve and the one-way valve being in series and disposed between the second high pressure tube and the low pressure tube.

4. A control method of a triple-tube air conditioning system, characterized by being applied to the triple-tube air conditioning system of any one of claims 1 to 3, the control method of the triple-tube air conditioning system comprising:

if the exhaust temperature is increased at a first speed, determining a target opening according to a preset first opening and a real-time opening, wherein the real-time opening comprises an initial opening; and if the exhaust temperature is reduced at the second speed, determining the target opening according to the preset second opening and the real-time opening so as to enable the lubricating oil in the system to return to the compressor.

5. The method for controlling a triple-tube air conditioning system according to claim 4, wherein after the step of detecting the temperature of the exhaust gas in real time, further comprising:

6. The control method of a triple-tube air conditioning system according to claim 4, comprising:

if the air conditioning mode is a refrigeration mode, opening an electromagnetic valve and a one-way valve which are connected in parallel with the capillary tube so as to drain the accumulated liquid in the second high-pressure tube into the low-pressure tube.

7. The method of controlling a triple tube air conditioning system according to claim 6, wherein the step of opening the solenoid valve and the check valve connected in parallel with the capillary tube comprises:

and opening the electromagnetic valve and the one-way valve which are connected with the capillary tube in parallel according to the opening time, wherein the opening time is determined by the pipe diameter and the pipe length of the second high-pressure pipe.

8. A triple-tube air conditioning system comprising a memory, a processor, and a control program of the triple-tube air conditioning system stored in the memory and executable on the processor, the control program of the triple-tube air conditioning system, when executed by the processor, implementing the steps of the control method of the triple-tube air conditioning system of any of claims 4-7.

9. A computer-readable storage medium storing a control program of a triple-tube air conditioning system, which when executed by a processor, implements the respective steps of the control method of the triple-tube air conditioning system according to any one of claims 4 to 7.