Air conditioning system and control method, device and storage medium thereof

Abstract

The application provides an air conditioning system and a control method, device and storage medium thereof. The air conditioning system comprises a first conveying pipe of a gas-liquid separator in communication with a second end of an indoor heat exchanger, a second conveying pipe of the gas-liquid separator in communication with a first end of an outdoor heat exchanger, a third conveying pipe of the gas-liquid separator connected to a return gas pipe between a four-way valve and a compressor and in communication with the return gas pipe, or the third conveying pipe of the gas-liquid separator being connected to a medium-pressure cavity of the compressor, and the gas-liquid separator performing gas-liquid separation on refrigerant from the first conveying pipe or the second conveying pipe, and gaseous refrigerant separated out being output from the third conveying pipe. The application performs good gas-liquid separation on refrigerant from the indoor heat exchanger or the outdoor heat exchanger, gaseous refrigerant is not input into the outdoor heat exchanger, and the utilization rate of the heat exchange area of the outdoor heat exchanger, the heat exchange performance and the energy efficiency are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electrical equipment, and particularly relates to an air conditioning system and a control method, device and storage medium thereof. BACKGROUND

[0002] In the air conditioning system, a gas-liquid separator is used to separate gaseous refrigerant and liquid refrigerant. In the related art, under a heating operating condition, the gaseous refrigerant and the liquid refrigerant separated by the gas-liquid separator are both input into an outdoor heat exchanger. However, since the heat exchange coefficient of the gaseous refrigerant in the outdoor heat exchanger is very low, directly inputting the gaseous refrigerant into the outdoor heat exchanger will cause waste of the heat exchange area of the outdoor heat exchanger. Moreover, under a refrigerating operating condition, the refrigerant is output from the outdoor heat exchanger, enters the gas-liquid separator through the outlet of the gas-liquid separator, and in this case, the effect of gas-liquid separation cannot be achieved, so that the refrigerant input into the indoor heat exchanger is gaseous-liquid mixed refrigerant, which leads to reduction of the heat exchange performance of the indoor heat exchanger. SUMMARY

[0003] The present application provides an air conditioning system and a control method, device and storage medium thereof. The gaseous refrigerant and the liquid refrigerant from the indoor heat exchanger or the outdoor heat exchanger are well separated by the gas-liquid separator, which solves the problem of insufficient refrigerating capacity caused by the failure to achieve gas-liquid separation under the refrigerating operating condition in the related art. Moreover, the gaseous refrigerant can not be input into the outdoor heat exchanger, so as to improve the utilization rate of the heat exchange area of the outdoor heat exchanger and improve the heat exchange performance and energy efficiency of the outdoor heat exchanger.

[0004] The first aspect of the present application provides an air conditioning system, comprising a compressor, an outdoor heat exchanger, a gas-liquid separator, an indoor heat exchanger, a four-way valve and a first throttling device.

[0005] The first throttling device is arranged between the first conveying pipe of the gas-liquid separator and the second end of the indoor heat exchanger, the second conveying pipe of the gas-liquid separator is in communication with the first end of the outdoor heat exchanger, the third conveying pipe of the gas-liquid separator is connected to the gas return pipe between the four-way valve and the compressor and is in communication with the gas return pipe, or the third conveying pipe is connected to the first chamber of the compressor and is in communication with the first chamber.

[0006] The gas-liquid separator separates the refrigerant from the first conveying pipe or the second conveying pipe, and the separated gaseous refrigerant is output from the third conveying pipe.

[0007] The embodiment of the second aspect of the application provides a control method of an air conditioning system, a second conveying pipe of a gas-liquid separator in the air conditioning system is communicated with a first end of an outdoor heat exchanger; a third conveying pipe of the gas-liquid separator is connected to a gas return pipe between a four-way valve and a compressor through a first control valve and is communicated with the gas return pipe; or the third conveying pipe is connected to a first chamber of the compressor through the first control valve and is communicated with the first chamber; the gas-liquid separator performs gas-liquid separation on refrigerant from the first conveying pipe or the second conveying pipe, and gaseous refrigerant separated out is output from the third conveying pipe; and the method comprises the following steps:

[0008] In a heating operating mode, whether refrigerant is uniformly distributed between flow paths of the outdoor heat exchanger is detected, and a detection result is obtained;

[0009] A superheat degree of the compressor and a valve closing duration of the first control valve each time the valve is closed are recorded;

[0010] Based on the detection result, the superheat degree of the compressor and the valve closing duration of the first control valve, communication or disconnection of the first control valve is controlled.

[0011] The embodiment of the third aspect of the application provides a control device of the air conditioning system of the first aspect, the device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the processor executes the computer program to implement the method of the second aspect.

[0012] The embodiment of the fourth aspect of the application provides a computer readable storage medium, and a computer program is stored on the computer readable storage medium, and the program is executed by a processor to implement the method of the second aspect.

[0013] The technical scheme provided in the embodiments of the application has at least the following technical effects or advantages:

[0014] In the embodiments of the application, the gas-liquid separator is used to perform good gas-liquid separation on refrigerant from the indoor heat exchanger or the outdoor heat exchanger, and the problem of insufficient refrigeration capacity caused by the inability to perform gas-liquid separation in the related art in a refrigeration operating mode is solved. The third conveying pipe of the gas-liquid separator is connected to the gas return pipe between the four-way valve and the compressor or is connected to the first chamber of the compressor. Gaseous refrigerant is output from the third conveying pipe and flows back to the compressor. In this way, the gaseous refrigerant can not be input to the outdoor heat exchanger, thereby improving the utilization rate of the heat exchange area of the outdoor heat exchanger and improving the heat exchange performance and energy efficiency of the outdoor heat exchanger.

[0015] Further, based on whether the distribution between the flow paths of the outdoor heat exchanger is uniform in the heating process, the first control valve is controlled to be connected or disconnected, which can maximize the uniform distribution of the outdoor heat exchanger, thereby improving the heat exchange performance and energy efficiency of the air conditioning system. By flexibly controlling the connection or disconnection of the first control valve, the gaseous refrigerant input into the outdoor heat exchanger and the direct output of the liquid refrigerant from the third delivery pipe of the gas-liquid separator can be reduced, which helps to reduce the overheat of the compressor or the exhaust gas overheat. In the refrigeration process, the purity of the liquid refrigerant input into the indoor heat exchanger can be maximized, and the mixed gaseous refrigerant can be reduced, thereby reducing the noise of the first throttling device, making the actual maximum flow of the first throttling device consistent with the design value, and improving the heat exchange performance and energy efficiency of the indoor heat exchanger.

[0016] Additional aspects and advantages of the application will be set forth in part in the description that follows, and in part will become apparent to those having ordinary skill in the art upon examination of the following or can be learned from practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0017] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not intended to limit the scope of the application. Moreover, the same reference numerals are used throughout the same figures.

[0018] In the drawings:

[0019] Figure 1 A first structural schematic diagram of an air conditioning system provided by an embodiment of the application is shown;

[0020] Figure 2 A second structural schematic diagram of an air conditioning system provided by an embodiment of the application is shown;

[0021] Figure 3 A third structural schematic diagram of an air conditioning system provided by an embodiment of the application is shown;

[0022] Figure 4 A fourth structural schematic diagram of an air conditioning system provided by an embodiment of the application is shown;

[0023] Figure 5 A schematic diagram of the cross-sectional structure of the gas-liquid separator provided by an embodiment of the application along the axial direction is shown;

[0024] Figure 6 Another schematic diagram of the cross-sectional structure of the gas-liquid separator provided by an embodiment of the application along the axial direction is shown;

[0025] Figure 7Fig. 7 shows a seventh structural schematic diagram of an air conditioning system according to an embodiment of the present application;

[0026] Figure 8 Fig. 6 shows a sixth structural schematic diagram of an air conditioning system according to an embodiment of the present application;

[0027] Figure 9 Fig. 7 shows a seventh structural schematic diagram of an air conditioning system according to an embodiment of the present application;

[0028] Figure 10 Fig. 8 shows an eighth structural schematic diagram of an air conditioning system according to an embodiment of the present application;

[0029] Figure 11 Fig. 9 shows a flow chart of a control method of an air conditioning system according to an embodiment of the present application;

[0030] Figure 12 Fig. 10 shows a control flow chart of a first control valve in a heating condition according to an embodiment of the present application;

[0031] Figure 13 Fig. 11 shows a flow chart of detecting whether each flow path of an outdoor heat exchanger is evenly divided according to an embodiment of the present application;

[0032] Figure 14 Fig. 12 shows a control flow chart of a first control valve in a cooling condition according to an embodiment of the present application;

[0033] Figure 15 Fig. 13 shows another control flow chart of a first control valve in a heating condition according to an embodiment of the present application;

[0034] Figure 16 Fig. 14 shows another control flow chart of a first control valve in a cooling condition according to an embodiment of the present application;

[0035] Figure 17 Fig. 15 shows a structural block diagram of a control device of an air conditioning system according to an embodiment of the present application;

[0036] Figure 18 Fig. 16 shows a structural schematic diagram of a control device of an air conditioning system according to an embodiment of the present application;

[0037] Figure 19 Fig. 17 shows a schematic diagram of a storage medium according to an embodiment of the present application.

[0038] The meanings of the respective labels in the above-mentioned figures are shown as follows:

[0039] 1: compressor, 2: outdoor heat exchanger, 3: gas-liquid separator, 4: indoor heat exchanger, 5: first control valve, 8: second control valve, 9: third control valve, 10: fourth control valve, 11: fifth control valve, 12: low-pressure tank, 13: four-way valve, 14: first chamber, 15: first distributor, 16: second distributor, 17: first throttling device, 18: second throttling device, 19: first temperature sensor, 20: first pressure sensor, 21: second temperature sensor, 22: second pressure sensor; 41: first end of indoor heat exchanger, 42: second end of indoor heat exchanger, 210: first end of outdoor heat exchanger, 220: second end of outdoor heat exchanger;

[0040] i: first conveying pipe, j: second conveying pipe, k: third conveying pipe. DETAILED DESCRIPTION

[0041] Exemplary embodiments of the present application will be described herein below with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it is understood that the present application can be embodied in various forms and should not be limited by 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 application to those skilled in the art.

[0042] It should be noted that, unless otherwise specified, technical or scientific terms used in the present application should be understood as their common meanings to those skilled in the art to which the present application pertains.

[0043] A kind of air conditioning system and its control method, device and storage medium according to the air conditioning system and its control method, device and storage medium according to the embodiments of the present application will be described below in conjunction with the drawings.

[0044] At present, the air conditioning system of the related art adopts a gas-liquid separator to separate gaseous refrigerant and liquid refrigerant. The gas-liquid separator is connected to an outdoor heat exchanger through two groups of branch lines, which are a gas pipe for conveying gaseous refrigerant and a liquid pipe for conveying liquid refrigerant. The gaseous refrigerant separated by the gas-liquid separator is input into the outdoor heat exchanger through the gas pipe, and the liquid refrigerant separated by the gas-liquid separator is input into the outdoor heat exchanger through the liquid pipe. In this way, both the gaseous refrigerant and the liquid refrigerant are input into the outdoor heat exchanger.

[0045] However, the heat exchange coefficient of the gaseous refrigerant in the outdoor heat exchanger is very low. Directly inputting the gaseous refrigerant into the outdoor heat exchanger will cause waste of the heat exchange area of the outdoor heat exchanger. In the case where the refrigerant is output from the outdoor heat exchanger and enters the separation chamber of the gas-liquid separator through the outlet of the gas-liquid separator in a refrigeration mode, the gas-liquid separation effect cannot be achieved, so that the refrigerant input into the indoor heat exchanger is gaseous-liquid mixed refrigerant, which reduces the heat exchange performance of the indoor heat exchanger.

[0046] Based on this, the air conditioning system provided by the embodiments of the present application can realize gas-liquid separation of refrigerant in heating and cooling conditions, reduce the situation that the refrigerant mixed with gas and liquid in the cooling condition enters the indoor heat exchanger to cause insufficient refrigerant circulation, and improve the heat exchange performance and energy efficiency ratio of the indoor heat exchanger in the cooling condition. Moreover, the gaseous refrigerant separated in the heating condition can not be directly input into the outdoor heat exchanger, so that the heat exchange area of the outdoor heat exchanger can be fully utilized, and the heat exchange performance and energy efficiency ratio of the outdoor heat exchanger are improved.

[0047] Referring to Figure 1 , the air conditioning system comprises a compressor 1, an outdoor heat exchanger 2, a gas-liquid separator 3, an indoor heat exchanger 4, a four-way valve 13 and a first throttling device 17.

[0048] The four-way valve 13 is in communication with the compressor 1, the second end 220 of the outdoor heat exchanger 2 and the first end 41 of the indoor heat exchanger 4, respectively. The first throttling device 17 is arranged between the first delivery pipe i of the gas-liquid separator 3 and the second end 42 of the indoor heat exchanger 4, the second delivery pipe j of the gas-liquid separator 3 is in communication with the first end 210 of the outdoor heat exchanger 2, and the third delivery pipe k of the gas-liquid separator 3 is connected to and in communication with the gas return pipe between the four-way valve 13 and the compressor 1. The gas-liquid separator 3 separates the refrigerant from the first delivery pipe i or the second delivery pipe j into gas and liquid, and the separated gaseous refrigerant is output from the third delivery pipe k.

[0049] Alternatively, as shown in Figure 2 , the third delivery pipe k is connected to and in communication with the first chamber 14 of the compressor 1, and the first chamber 14 can comprise a medium-pressure chamber of the compressor 1. Direct delivery of the gaseous refrigerant to the first chamber 14 of the compressor 1 can realize the effect of jet augmenting enthalpy, increase the gas return superheat of the compressor 1, and reduce the exhaust temperature of the compressor 1.

[0050] Figure 1 And 2 , the gas-liquid separator 3 has a bidirectional separation function, and the first delivery pipe i and the second delivery pipe j can both serve as a refrigerant inlet or a refrigerant outlet. The gas-liquid separator 3 can separate the refrigerant entering the separation chamber from the first delivery pipe i or the second delivery pipe j into gas and liquid.

[0051] Figure 1 And 2 , the arrows in the figures all refer to the flow direction of the refrigerant in the air conditioning system in the heating condition. Figure 1 2 In the figures, a low-pressure tank 12 is further connected to the gas return pipe between the four-way valve 13 and the compressor 1. In actual application, the low-pressure tank 12 can also not be arranged on the gas return pipe between the four-way valve 13 and the compressor 1, and the present application does not limit this.​

[0052] Under heating conditions, the refrigerant flows from the outlet of compressor 1, flows into indoor heat exchanger 4 from first end 41 of indoor heat exchanger 4, releases heat in indoor heat exchanger 4, then flows out from second end 42 of indoor heat exchanger 4, passes through first throttling device 17, and flows into gas-liquid separator 3 from first delivery pipe i of gas-liquid separator 3. Gas and liquid are separated in gas-liquid separator 3, and the separated liquid refrigerant with higher purity flows out from second delivery pipe j of gas-liquid separator 3, flows into outdoor heat exchanger 2 from first end 210, and flows out from second end 220 of outdoor heat exchanger 2. It then flows through four-way valve 13 and low-pressure tank 12, and returns to compressor 1 from the inlet. The higher-purity gaseous refrigerant separated by gas-liquid separator 3 can be output from third delivery pipe k of gas-liquid separator 3, passes through low-pressure tank 12, and returns to compressor 1 from the inlet. Under heating conditions, the refrigerant circulates throughout the air-conditioning system in this manner, achieving indoor heating.

[0053] During this process, since the gaseous refrigerant can be output from the third delivery pipe k of the gas-liquid separator 3 back to the compressor 1, the gaseous refrigerant does not need to be directly input into the outdoor heat exchanger 2. The refrigerant input into the outdoor heat exchanger 2 is a liquid refrigerant with higher purity. The heat transfer coefficient of the liquid refrigerant in the outdoor heat exchanger 2 is higher, so that the heat transfer area of ​​the outdoor heat exchanger 2 can be fully utilized, thereby improving the heat transfer performance and energy efficiency of the outdoor heat exchanger 2, and thereby improving the heating performance of the entire air-conditioning system under heating conditions.

[0054] In the cooling condition, the four-way valve 13 is reversed, so that the outlet of the compressor 1 is connected to the second end 220 of the outdoor heat exchanger 2, and the first end 41 of the indoor heat exchanger 4 is connected to the inlet of the compressor 1. The flow direction of the refrigerant is the same as that of the compressor 1. Figure 1 The flow direction in is opposite. Figure 3 As shown, the refrigerant flows out of the outlet of the compressor 1, flows into the outdoor heat exchanger 2 from the second end 220 of the outdoor heat exchanger 2, then flows out of the first end 210 of the outdoor heat exchanger 2, flows into the gas-liquid separator 3 from the second delivery pipe j of the gas-liquid separator 3, undergoes gas-liquid separation in the gas-liquid separator 3, and the separated liquid refrigerant with higher purity flows out of the first delivery pipe i of the gas-liquid separator 3, passes through the first throttling device 17, flows into the indoor heat exchanger 4 from the second end 42 of the indoor heat exchanger 4, flows out from the first end 41 of the indoor heat exchanger 4, and returns to the compressor 1 from the inlet of the compressor 1. The higher-purity gaseous refrigerant separated by the gas-liquid separator 3 can be output from the third delivery pipe k of the gas-liquid separator 3 and returned to the compressor 1 from the inlet of the compressor 1. Under cooling conditions, the refrigerant circulates throughout the air-conditioning system in the above manner, achieving the function of indoor cooling.

[0055] In the case that the third delivery pipe k of the gas-liquid separator 3 is connected to the first chamber 14 of the compressor 1, the flow direction of the refrigerant in the refrigeration mode is as shown in FIG. 4. Figure 4

[0056] In the refrigeration process, the gas-liquid separation can also be realized when the refrigerant is input from the second delivery pipe j of the gas-liquid separator 3, and the separated liquid refrigerant with high purity flows into the indoor heat exchanger 4. In the case that a throttling device is arranged between the gas-liquid separator 3 and the indoor heat exchanger 4, the liquid refrigerant with high purity flows through the throttling device, and the noise of the throttling device is small. Since the maximum flow value of the throttling device is designed based on the liquid refrigerant in the design process, the liquid refrigerant with high purity flows through the throttling device, so that the actual maximum flow of the throttling device is consistent with the design value, the insufficient refrigerant flow into the indoor heat exchanger 4 is reduced, and the insufficient refrigeration capacity and the energy efficiency reduction of the air conditioning system caused by the insufficient refrigerant flow are reduced.

[0057] Since the gas-liquid separation can be realized for the refrigerant input from the first delivery pipe i or the second delivery pipe j in the gas-liquid separator 3 in the heating mode and the refrigeration mode, the problem that the refrigerant input into the gas-liquid separator from the outdoor heat exchanger 2 in the refrigeration mode cannot realize gas-liquid separation in the related art is solved.

[0058] The first throttling device 17 throttles the refrigerant flowing through the pipeline between the gas-liquid separator 3 and the indoor heat exchanger 4. In the refrigeration mode, the liquid refrigerant output from the first delivery pipe i of the gas-liquid separator 3 flows into the indoor heat exchanger 4 after being throttled by the first throttling device 17. Since the liquid refrigerant separated by the gas-liquid separator 3 has high purity, the noise of the first throttling device 17 is reduced, and the actual maximum flow of the first throttling device 17 is consistent with the design value, so that the insufficient system capacity and the energy efficiency reduction caused by the insufficient refrigerant circulation flow in the refrigeration mode are avoided.

[0059] As shown in FIGS. 5 and 6, Figure 1 and 2 The air conditioning system further includes a first control valve 5, a first end of the first control valve 5 is connected to the third delivery pipe k, and a second end of the first control valve 5 is connected to the gas return pipeline between the four-way valve 13 and the compressor 1 or the first chamber 14 of the compressor 1. The pressure in the gas-liquid separator 3 is adjusted by controlling the connection or disconnection of the first control valve 5, so that the separated gaseous refrigerant can be output from the third delivery pipe k.

[0060] In some embodiments of the present application, the gas-liquid separator 3 can realize gas-liquid separation for the refrigerant from the indoor heat exchanger 4 and the outdoor heat exchanger 2. Figure 5 The axial cross-sectional view of the gas-liquid separator 3 is shown in FIG. 7, and the structure of the gas-liquid separator 3 is shown in FIG. 8. Figure 5 ​As shown, the third delivery pipe k of the gas-liquid separator 3 is arranged at the upper portion of the gas-liquid separator 3, and the second delivery pipe j is arranged at the lower portion of the gas-liquid separator 3. The first delivery pipe i is arranged on the side wall of the gas-liquid separator 3, and the position of the first delivery pipe i is lower than the position of the third delivery pipe k and higher than the position of the second delivery pipe j. The port of the second delivery pipe j is oriented in such a way that the refrigerant input from the second delivery pipe j can be sprayed onto the side wall and / or the bottom surface of the gas-liquid separator 3. Figure 5 The angle a is the possible angle range between the port orientation of the third delivery pipe k and the horizontal line, the angle b is the possible angle range between the port orientation of the first delivery pipe i and the horizontal line, and the angle c is the possible angle range between the port orientation of the second delivery pipe j and the horizontal line.

[0061] Figure 5 As shown, the third delivery pipe k of the gas-liquid separator 3 is arranged at the upper portion of the gas-liquid separator 3, and the second delivery pipe j is arranged at the lower portion of the gas-liquid separator 3. The first delivery pipe i is arranged on the side wall of the gas-liquid separator 3, and the position of the first delivery pipe i is lower than the position of the third delivery pipe k and higher than the position of the second delivery pipe j. The port of the second delivery pipe j is oriented in such a way that the refrigerant input from the second delivery pipe j can be sprayed onto the side wall and / or the bottom surface of the gas-liquid separator 3.

[0062] The second delivery pipe j is arranged on the bottom surface of the gas-liquid separator 3, and the port of the second delivery pipe j is oriented in such a way that the refrigerant from the outdoor heat exchanger 2 can be sprayed onto the side wall and / or the bottom surface of the gas-liquid separator 3. The refrigerant sprayed onto the side wall will be subjected to gas-liquid separation under the action of gravity and centrifugal force, and the refrigerant sprayed onto the bottom surface will also be subjected to a certain gas-liquid separation effect under the action of centrifugal force. The separated gaseous refrigerant can be output from the third delivery pipe k at the top, and the separated liquid refrigerant can be output from the first delivery pipe i after accumulating in the gas-liquid separator 3 to be higher than the first delivery pipe i.

[0063] The above-described gas-liquid separator 3 can achieve good gas-liquid separation effect in both heating and cooling conditions, and only one component, i.e., the gas-liquid separator 3, is used to achieve bidirectional gas-liquid separation, thereby reducing product cost.

[0064] In some embodiments of the present application, in the above-described gas-liquid separator 3, the port of the second delivery pipe j is oriented towards the bottom surface or the side wall of the gas-liquid separator 3, and the included angle between the port orientation of the second delivery pipe j and the vertical line of the bottom surface is greater than or equal to 0° and less than a preset angle, which is the obtuse angle between the port orientation of the first delivery pipe i and the vertical line of the bottom surface.

[0065] The port of the second delivery pipe j is directed towards the bottom surface or the side wall of the gas-liquid separator 3, which can ensure that the refrigerant sprayed from the second delivery pipe j can be sprayed onto the side wall and / or the bottom surface of the gas-liquid separator 3, and is conducive to achieving a better gas-liquid separation effect. When the port of the second delivery pipe j is directed towards the bottom surface of the gas-liquid separator 3 and the included angle between the port and the vertical line of the bottom surface is equal to 0°, the refrigerant sprayed from the second delivery pipe j will be sprayed vertically onto the bottom surface of the gas-liquid separator 3.

[0066] When the port of the second delivery pipe j is directed towards the side wall of the gas-liquid separator 3 and the included angle between the port and the vertical line of the bottom surface is close to the preset angle, as shown by the arrow at the second delivery pipe j in the middle, Figure 6 When the port of the second delivery pipe j is directed towards the side wall of the gas-liquid separator 3 and the included angle between the port and the vertical line of the bottom surface is close to the preset angle, as shown by the arrow at the second delivery pipe j in the middle,

[0067] When the port of the second delivery pipe j is directed towards the side wall of the gas-liquid separator 3 and the included angle between the port and the vertical line of the bottom surface is close to the preset angle, as shown by the arrow at the second delivery pipe j in the middle,

[0068] In some embodiments, in the gas-liquid separator 3, the included angle between the port of the third delivery pipe k and the top surface of the gas-liquid separator 3 can be within [0°, 90°], for example, the included angle can be 0°, 30°, 50° or 90°, etc. The port of the third delivery pipe k is directed towards the gas-liquid separator 3, and there are two included angles between the port and the gas-liquid separator 3, and the two included angles are complementary. Here, the included angle within [0°, 90°] refers to the smaller included angle of the two included angles.

[0069] After the gas-liquid separator 3 separates the gaseous refrigerant and the liquid refrigerant, the liquid refrigerant will accumulate at the bottom of the gas-liquid separator 3, and the gaseous refrigerant will fill in the space between the upper surface of the liquid refrigerant and the top of the gas-liquid separator 3. The included angle between the port of the third delivery pipe k and the top surface is within [0°, 90°], which is conducive to the gaseous refrigerant being output from the third delivery pipe k to outside the gas-liquid separator 3.

[0070] In the embodiments of the present application, the port of the first conveying pipe i is inclined towards a direction parallel to the top surface or the bottom surface, and the inclination angle is within the range of (0°, 10°]. Thus, the port of the first conveying pipe i is not directed towards the top surface, so that the refrigerant sprayed from the first conveying pipe i cannot be directly sprayed from the third conveying pipe k to the outside of the bidirectional separator. The inclination angle of the first conveying pipe i towards the bottom surface is within the range of (0°, 10°], so that the refrigerant sprayed from the first conveying pipe i can be sprayed to a position relatively high on the side wall opposite to the side wall where the first conveying pipe i is located, and thus the refrigerant can be better separated under the action of gravity and centrifugal force.

[0071] In the embodiments of the present application, the first conveying pipe i, the second conveying pipe j and the third conveying pipe k can all be pipes arranged on the corresponding surfaces of the gas-liquid separator 3 and do not extend into the separation cavity of the gas-liquid separator 3. The orientations of the ports of the above three conveying pipes can be achieved by setting the inclination angles of the pipes of the three conveying pipes.

[0072] In some other embodiments of the present application, the pipes can also extend into the separation cavity of the gas-liquid separator 3, and the ends of the pipes extending into the separation cavity are provided with openings, which are the ports of the conveying pipes. The inclination directions of the pipes arranged in the separation cavity are set to achieve the orientations of the ports of the above three conveying pipes.

[0073] In some other embodiments of the present application, the air conditioning system further comprises a plurality of control valves, and the bidirectional gas-liquid separation function is achieved by combining one gas-liquid separator and a plurality of control valves. Figure 7 As shown in the figure, the air conditioning system further comprises a second control valve 8, a third control valve 9, a fourth control valve 10 and a fifth control valve 11.

[0074] The second control valve 8 has a first end and a second end, the first end of the second control valve 8 is located between the first conveying pipe i of the gas-liquid separator 3 and the fifth control valve 11, and the second end of the second control valve 8 is located between the third control valve 9 and the first throttling device 17. The fourth control valve 10 has a first end and a second end, the first end of the fourth control valve 10 is located between the third control valve 9 and the second conveying pipe j, and the second end of the fourth control valve 10 is located between the first end 210 of the outdoor heat exchanger 2 and the fifth control valve 11.

[0075] The above-mentioned second control valve 8, third control valve 9, fourth control valve 10 and fifth control valve 11 can be control valves with electrically driven control function, or can be passive control valves such as one-way valves.

[0076] The first delivery pipe i of the gas-liquid separator 3 is a refrigerant inlet, and the second delivery pipe j is a refrigerant outlet. In the heating mode, the second control valve 8 and the fourth control valve 10 are connected, and the third control valve 9 and the fifth control valve 11 are disconnected. The refrigerant from the indoor heat exchanger 4 enters the separation cavity of the gas-liquid separator 3 from the first delivery pipe i of the gas-liquid separator 3 through the second control valve 8, and the separated liquid refrigerant flows out of the second delivery pipe j of the gas-liquid separator 3 and enters the outdoor heat exchanger 2 through the fourth control valve 10. The flow direction of the refrigerant in the heating mode is shown in FIG. 4. Figure 5

[0077] In the cooling mode, the third control valve 9 and the fifth control valve 11 are connected, and the second control valve 8 and the fourth control valve 10 are disconnected. The refrigerant from the outdoor heat exchanger 2 enters the separation cavity of the gas-liquid separator 3 from the first delivery pipe i of the gas-liquid separator 3 through the fifth control valve 11, and the separated liquid refrigerant flows out of the second delivery pipe j of the gas-liquid separator 3 and enters the indoor heat exchanger 4 through the third control valve 9. The flow direction of the refrigerant in the cooling mode is shown in FIG. 5. Figure 8

[0078] Through the structural combination of the gas-liquid separator 3 and the second control valve 8, the third control valve 9, the fourth control valve 10, and the fifth control valve 11, the refrigerant from the outdoor heat exchanger 2 can be delivered to the first delivery pipe i of the gas-liquid separator 3, and then enter the separation cavity for gas-liquid separation. The separated liquid refrigerant is output from the second delivery pipe j and delivered to the indoor heat exchanger 4 through the pipeline where the third control valve 9 is located. In this way, the refrigerant from the indoor heat exchanger 4 or the outdoor heat exchanger 2 can be subjected to gas-liquid separation, so that the flow of the liquid refrigerant entering the indoor heat exchanger 4 in the cooling mode is sufficient, the heat exchange performance of the indoor heat exchanger 4 in the cooling mode is improved, and the cooling performance of the air conditioning system is improved.

[0079] In other embodiments, the third delivery pipe k of the gas-liquid separator 3 is connected to the first control valve 5 through the second throttling device 18, and the first control valve 5 can be directly connected to the first chamber 14 of the compressor 1, so as to realize the effect of jet augmenting enthalpy, increase the superheat degree of the return gas of the compressor 1, and reduce the exhaust temperature of the compressor 1.

[0080] As shown in FIG. 6, the first control valve 5 is directly connected to the first chamber 14 of the compressor 1. Figure 9 FIG. 6 shows a schematic diagram of the flow direction of the refrigerant in the heating mode when the first control valve 5 is directly connected to the first chamber 14 of the compressor 1. Figure 10 FIG. 7 shows a schematic diagram of the flow direction of the refrigerant in the cooling mode when the first control valve 5 is directly connected to the first chamber 14 of the compressor 1.

[0081] In the embodiments of the present application, Figure 1 The first control valve 5 is used to control the connection or disconnection of the pipeline for delivering the gaseous refrigerant from the third delivery pipe k of the gas-liquid separator 3.​​

[0082] As Figures 1-4 , 7-10, the air conditioning system further comprises a low-pressure tank 12. Wherein, the four-way valve 13 is connected with the compressor 1, the first end 41 of the indoor heat exchanger 4, the second end 220 of the outdoor heat exchanger 2 and the inlet of the low-pressure tank 12 respectively; the first end of the first control valve 5 is communicated with the third delivery pipe k of the gas-liquid separator 3. The second end of the first control valve 5 can be connected to the gas return pipe between the four-way valve 13 and the compressor 1.

[0083] The second end of the first control valve 5 is connected to the gas return pipe between the four-way valve 13 and the compressor 1, so that the gaseous refrigerant output by the third delivery pipe k of the gas-liquid separator 3 can be directly output to the gas return pipe between the four-way valve 13 and the compressor 1, thereby the gaseous refrigerant can not be input to the outdoor heat exchanger 2, and the heat exchange performance and energy efficiency of the outdoor heat exchanger 2 are improved. Moreover, directly inputting the gaseous refrigerant to the pipe between the four-way valve 13 and the inlet of the low-pressure tank 12 is conducive to reducing the exhaust temperature of the compressor 1.

[0084] As Figures 1-4 , 7-10, the air conditioning system further comprises a first distributor 15 and a second distributor 16. Wherein, the main pipe end of the first distributor 15 is communicated with the second delivery pipe j, and each branch end of the first distributor 15 is communicated with the first end of each flow path in the outdoor heat exchanger 2 respectively; the main pipe end of the second distributor 16 is communicated with the four-way valve 13, and each branch end of the second distributor 16 is communicated with the second end of each flow path in the outdoor heat exchanger 2 respectively.

[0085] Wherein, each branch of the first distributor 15 and each branch of the second distributor 16 are connected with each flow path in the outdoor heat exchanger 2 one by one. That is, for one flow path in the outdoor heat exchanger 2, one end of the flow path is connected with one branch of the first distributor 15, and the other end of the flow path is connected with one branch of the second distributor 16.

[0086] In the heating operating condition, the refrigerant from the indoor heat exchanger 4 enters the separation cavity of the gas-liquid separator 3 from the first delivery pipe i, and separates into gaseous refrigerant and liquid refrigerant in the separation cavity. Among them, the liquid refrigerant is output from the second delivery pipe j of the gas-liquid separator 3, enters each branch of the first distributor 15 from the main pipe end of the first distributor 15, enters each flow path in the outdoor heat exchanger 2 from each branch end of the first distributor 15, then enters each branch of the second distributor 16 from each flow path of the outdoor heat exchanger 2, and finally converges to the main pipe of the second distributor 16, is output from the main pipe end of the second distributor 16, enters the low-pressure tank 12 after passing through the four-way valve 13, and is input to the compressor 1 from the low-pressure tank 12.

[0087] In the refrigeration mode, the refrigerant outputted from the compressor 1 passes through the four-way valve 13, enters the manifold of the second distributor 16, is branched from the manifold end of the second distributor 16 to each branch of the second distributor 16, and then flows into each flow path of the outdoor heat exchanger 2 from each branch of the second distributor 16. Then, the refrigerant flows into each branch of the first distributor 15 from each flow path of the outdoor heat exchanger 2, and then converges into the manifold of the first distributor 15. The refrigerant is outputted from the manifold of the first distributor 15, enters the separation cavity through the second delivery pipe j of the gas-liquid separator 3, and the separated liquid refrigerant is inputted into the indoor heat exchanger 4 from the first delivery pipe i. Finally, the refrigerant flows back to the compressor 1 from the first end 41 of the indoor heat exchanger 4 through the four-way valve 13 and the low-pressure tank 12.

[0088] The first distributor 15 and the second distributor 16 in the above embodiments can be a distributor in the form of a flute pipe or a capillary tube, Figures 1-4 The first distributor 15 and the second distributor 16 in 7-10 are schematically shown as distributors in the form of flute pipes. The distributors in the form of flute pipes have simpler structure, are standardized, and have low cost. Moreover, the pressure drop of the distributors in the form of flute pipes is smaller, and the use of the distributors in the form of flute pipes helps to reduce the flow path pressure drop in the heating mode, and improve the heat exchange capacity and efficiency of the air conditioning system.

[0089] As shown in 7-10, Figures 1-4 The air conditioning system further comprises a second throttling device 18, one end of the second throttling device 18 being in communication with the third delivery pipe k, and the other end of the second throttling device 18 being in communication with the first end of the first control valve 5.

[0090] As shown in 7-10, Figure 1 、 3 The first temperature sensor 19 is used for detecting the return gas temperature, and the first pressure sensor 20 is used for detecting the return gas pressure.

[0091] Figure 2 、 4 The second temperature sensor 21 is used for detecting the discharge temperature of the compressor 1, and the second pressure sensor 22 is used for detecting the discharge pressure of the compressor 1.

[0092] In the embodiments of the present application, the gas-liquid separator is used to separate the refrigerant from the indoor heat exchanger or the outdoor heat exchanger, thereby solving the problem of insufficient refrigeration capacity caused by the failure to separate the gas-liquid in the related art under the refrigeration condition. The third delivery pipe of the gas-liquid separator is connected to the pipeline between the second end of the outdoor heat exchanger and the compressor through the first control valve, and the gaseous refrigerant is output from the third delivery pipe and flows back to the compressor. In this way, the gaseous refrigerant can not be input into the outdoor heat exchanger, thereby improving the utilization rate of the heat exchange area of the outdoor heat exchanger and improving the heat exchange performance and energy efficiency of the outdoor heat exchanger.

[0093] In the embodiments of the present application, the first control valve is used to control the connection or disconnection of the pipeline through which the third delivery pipe of the gas-liquid separator outputs. Under the heating condition, after the first control valve is connected, the gaseous refrigerant separated in the gas-liquid separator is output from the third delivery pipe, the gas pressure in the separation cavity of the gas-liquid separator changes, and with the extension of time, liquid refrigerant may also flow out of the third delivery pipe. Therefore, the valve needs to be closed after a period of time. After a period of time, the gaseous refrigerant separated in the separation cavity of the gas-liquid separator is more and more, the gas pressure in the separation cavity is high, and a part of the gaseous refrigerant may be pressed out of the second delivery pipe and into the outdoor heat exchanger due to the gas pressure. The gaseous refrigerant entering the outdoor heat exchanger will affect the heat exchange performance of the outdoor heat exchanger. Therefore, under the heating condition, the connection or disconnection of the first control valve needs to be reasonably controlled.

[0094] Under the refrigeration condition, after the first control valve is connected, the gaseous refrigerant separated in the gas-liquid separator is also output from the third delivery pipe, the gas pressure in the separation cavity of the gas-liquid separator changes, and with the extension of time, liquid refrigerant may also flow out of the third delivery pipe. Therefore, the valve needs to be closed after a period of time. After a period of time, the gaseous refrigerant separated in the separation cavity of the gas-liquid separator is more and more, the gas pressure in the separation cavity is high, and a part of the gaseous refrigerant may be pressed out of the first delivery pipe and into the indoor heat exchanger due to the gas pressure. The gaseous refrigerant entering the indoor heat exchanger will affect the heat exchange performance of the indoor heat exchanger. Therefore, under the refrigeration condition, the connection or disconnection of the first control valve also needs to be reasonably controlled.

[0095] The embodiments of the present application provide a control method of the air conditioning system as described in any of the above embodiments, as shown in the method, the method specifically includes the following steps: Figure 11 The method specifically includes the following steps:

[0096] Step 101: under the heating condition, detecting whether the refrigerant is evenly distributed between the flow paths of the outdoor heat exchanger, and obtaining a detection result.

[0097] The execution subject of the embodiment of the application can be a controller in an air conditioning system. In a heating operating condition, the refrigerant first enters the indoor heat exchanger after coming out of the compressor, and then flows out of the indoor heat exchanger and is input into the separation cavity through the first conveying pipe of the gas-liquid separator. After the gaseous refrigerant and the liquid refrigerant are separated in the separation cavity, the gaseous refrigerant is output from the third conveying pipe of the gas-liquid separator. The liquid refrigerant flows out of the second conveying pipe of the gas-liquid separator and is input into the outdoor heat exchanger through the first distributor. The outdoor heat exchanger has a plurality of flow paths, and the refrigerant is distributed among the flow paths. The more uniform the distribution among the flow paths, the better the heat exchange performance of the outdoor heat exchanger. If the distribution among the flow paths is not uniform, the heat dissipation capacity of the outdoor heat exchanger will be attenuated.

[0098] When the first control valve is connected, the gaseous refrigerant is output from the third conveying pipe, and the gaseous refrigerant is not input into the outdoor heat exchanger. In this case, the outdoor heat exchanger inputs the liquid refrigerant with high purity, and the distribution of the flow paths of the outdoor heat exchanger is usually uniform. When the gaseous refrigerant is input into the outdoor heat exchanger, the liquid refrigerant is mixed with the gaseous refrigerant, which causes the distribution of the flow paths of the outdoor heat exchanger to be non-uniform.

[0099] Therefore, in the heating operating condition, when the first control valve is disconnected, whether the distribution of the flow paths of the outdoor heat exchanger is uniform is detected in real time.

[0100] Specifically, when the first control valve is disconnected, the average heat exchange coefficient of the outdoor heat exchanger in a first preset time period is obtained. Based on the fact that the heat exchange coefficients of the outdoor heat exchanger in a second preset time period are all less than the product of the average heat exchange coefficient and a preset attenuation coefficient, it is determined that the distribution of the flow paths of the outdoor heat exchanger is non-uniform. Based on the fact that the heat exchange coefficients of the outdoor heat exchanger in the second preset time period exist a case of being greater than or equal to the product, it is determined that the distribution of the flow paths of the outdoor heat exchanger is uniform.

[0101] The first preset time period is greater than the second preset time period, and the first preset time period can be 5 min, 6 min, 8 min, 10 min, etc. The second preset time period can be 1 min, 1.5 min, 1.8 min, 2 min, etc.

[0102] The heat exchange coefficient of the outdoor heat exchanger is determined every certain time interval within a first preset time period. The certain time interval can be 0.5 min or 1 min, etc. The calculation process of the heat exchange coefficient of the outdoor heat exchanger is as follows: the actual operating parameters of the compressor and the bypass flow in the pipeline of the air conditioning system are obtained. Based on the actual operating parameters of the compressor and the bypass flow, the refrigerant flow through the outdoor heat exchanger is calculated. The enthalpy difference of the air conditioning system is measured, and the product of the refrigerant flow through the outdoor heat exchanger and the enthalpy difference is calculated to obtain the heat exchange capacity of the outdoor heat exchanger. The outdoor ambient temperature is detected by the temperature sensor on the outdoor heat exchanger, and the temperature difference between the outdoor ambient temperature and the saturation temperature is calculated. The ratio of the heat exchange capacity of the outdoor heat exchanger to the temperature difference is calculated, and the ratio is taken as the heat exchange coefficient of the outdoor heat exchanger.

[0103] The actual operating parameters of the compressor can include volume, flow, suction pressure, discharge pressure, etc.

[0104] After the heat exchange coefficients of the outdoor heat exchanger at multiple time points are calculated in the above manner within the first preset time period, the multiple heat exchange coefficients are averaged to obtain the average heat exchange coefficient of the outdoor heat exchanger within the first preset time period. Then, the heat exchange coefficient of the outdoor heat exchanger is obtained every certain time interval, and after the heat exchange coefficient of the outdoor heat exchanger is obtained each time, it is determined whether the heat exchange coefficient is less than the product of the average heat exchange coefficient and a preset attenuation coefficient. The preset attenuation coefficient is a preconfigured attenuation coefficient of the heat exchange efficiency of the outdoor heat exchanger.

[0105] When the heat exchange coefficient is determined to be less than the average heat exchange coefficient for the first time, the timing is started, and the timing duration is compared with a second preset time period. If the timing duration is less than the second preset time period, it is continued to determine whether the heat exchange coefficient obtained each time is less than the average heat exchange coefficient in the above manner. If the heat exchange coefficient obtained at a certain time is determined to be greater than or equal to the second preset time period when the timing duration is less than the second preset time period, it is determined that the distribution among the flow paths of the outdoor heat exchanger is uniform, and the timing duration is cleared. If the heat exchange coefficient obtained each time is less than the average heat exchange coefficient during the timing duration reaches the second preset time period, it is determined that the distribution among the flow paths of the outdoor heat exchanger is not uniform.

[0106] Step 102: record the superheat of the compressor and the valve-closing duration of the first control valve each time the valve is closed.

[0107] In the heating operating condition, the valve-closing duration of the first control valve is also recorded when the first control valve is disconnected. The superheat of the compressor is obtained when the first control valve is connected, and the valve-closing duration of the first control valve is recorded when the first control valve is disconnected. Figures 10-13 In the case that the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the inlet of the compressor in the air conditioning system shown in FIG. 1, the superheat of the compressor is obtained. In the case that the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the outlet of the compressor in the air conditioning system shown in FIG. 2, the subcooling of the compressor is obtained. Figures 14-17The second end of the first control valve in the air conditioning system shown is communicated with the medium pressure cavity of the compressor, and the exhaust superheat degree of the compressor is recorded.

[0108] As shown in the air conditioning system shown in Figure 1 , 3 , 7 and 8, a first temperature sensor arranged on the pipeline between the four-way valve and the low-pressure tank detects the return gas temperature, a first pressure sensor detects the return gas pressure, the saturation temperature corresponding to the detected return gas pressure is obtained, the temperature difference between the return gas temperature and the saturation temperature is calculated, and the temperature difference is taken as the return gas superheat degree of the compressor.

[0109] As shown in the air conditioning system shown in Figure 2 , 4 , 9, 10, a second temperature sensor arranged on the pipeline at the outlet of the compressor detects the exhaust gas temperature, a second pressure sensor detects the exhaust gas pressure, the saturation temperature corresponding to the detected exhaust gas pressure is obtained, the temperature difference between the exhaust gas temperature and the saturation temperature is calculated, and the temperature difference is taken as the exhaust gas superheat degree of the compressor.

[0110] Step 103: based on the detection result, the superheat degree of the compressor and the valve closing time length of the first control valve, the communication or disconnection of the first control valve is controlled.

[0111] In the embodiment of the application, when the heating program opening instruction is detected to start heating, the first control valve is first controlled to be disconnected. The valve closing time length of the first control valve is recorded. It is judged whether the valve closing time length reaches the third preset time length. If not, the first control valve is continuously kept disconnected. If the valve closing time length of the first control valve reaches the third preset time length, the first control valve is controlled to be connected. The superheat degree of the compressor is obtained in real time after the first control valve is connected. It is judged whether the superheat degree of the compressor is lower than the first preset temperature threshold.

[0112] In the case that the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the inlet of the compressor, the return gas superheat degree of the compressor is obtained. In the case that the second end of the first control valve is communicated with the medium pressure cavity of the compressor, the exhaust gas superheat degree of the compressor is obtained. The first preset temperature threshold corresponding to the return gas superheat degree and the exhaust gas superheat degree is different.

[0113] In the case that the return gas superheat degree of the compressor is obtained, it is judged whether the obtained return gas superheat degree is lower than the corresponding first preset temperature threshold. If not, the first control valve is continuously kept connected. If yes, the first control valve is controlled to be disconnected, and the valve closing time length of this disconnection is recorded.

[0114] In the case where the obtained is the exhaust gas superheat degree of the compressor, it is judged whether the obtained exhaust gas superheat degree is lower than the corresponding first preset temperature threshold. If not, the first control valve is continuously kept in communication. If yes, the first control valve is controlled to be disconnected, and the valve closing time length of this disconnection is recorded.

[0115] After the first control valve is controlled to be disconnected this time, it is detected according to the operation of step 101 whether the distribution between the flow paths of the outdoor heat exchanger is uniform, based on the detection result indicating that the distribution is not uniform, and / or the valve closing time length of the first control valve this time reaches a fourth preset time length, the first control valve is controlled to be in communication.

[0116] The fourth preset time length can be 1 min, 1.5 min or 2 min, etc.

[0117] After the first control valve is controlled to be in communication, the superheat degree of the compressor is obtained again, and the communication or disconnection of the first control valve is controlled based on the superheat degree. If the first control valve is controlled to be disconnected after that, the communication or disconnection of the first control valve is controlled again based on the detection result of whether the distribution between the flow paths of the outdoor heat exchanger is uniform or the valve closing time length of the first control valve.

[0118] The communication or disconnection of the first control valve is controlled in the above-mentioned manner until the current heating program ends. In this way, during the entire heating process, the distribution of the outdoor heat exchanger can be kept as uniform as possible, thereby improving the heat exchange performance and energy efficiency of the air conditioning system. Moreover, it helps to reduce the situation that the superheat degree of the compressor is too low.

[0119] In the embodiments of the present application, the communication or disconnection of the first control valve also needs to be flexibly controlled in the refrigeration working condition. Specifically, in the refrigeration working condition, the superheat degree of the compressor and the valve closing time length of the first control valve each time are recorded. Based on the superheat degree or the valve closing time length of the first control valve, the communication or disconnection of the first control valve is controlled.

[0120] Similarly, in the case where the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the inlet of the compressor, the obtained is the superheat degree of the return gas of the compressor. In the case where the second end of the first control valve is in communication with the medium pressure cavity of the compressor, the obtained is the exhaust gas superheat degree of the compressor.

[0121] When the refrigeration program start instruction is detected, the first control valve is controlled to be disconnected, and the valve closing time length of this disconnection is recorded. Based on the valve closing time length of the first control valve reaching a fifth preset time length, the first control valve is controlled to be in communication. The fifth preset time length can be 5 min, 8 min or 10 min, etc.

[0122] After the first flow control valve is connected, based on the overheat degree of the compressor being lower than a second preset temperature threshold, the first control valve is controlled to be disconnected. In the embodiments of the present application, the second preset temperature thresholds corresponding to the overheat degrees of the return gas and the exhaust gas are different. In the case of obtaining the overheat degree of the return gas, based on the overheat degree of the return gas of the compressor being lower than the second preset temperature threshold corresponding to the overheat degree of the return gas, the first control valve is controlled to be disconnected. In the case of obtaining the overheat degree of the exhaust gas, based on the overheat degree of the exhaust gas of the compressor being lower than the second preset temperature threshold corresponding to the overheat degree of the exhaust gas, the first control valve is controlled to be disconnected.

[0123] After the first control valve is controlled to be disconnected, the valve closing time length of this time is also recorded, and based on the valve closing time length of this time of the first control valve reaching a sixth preset time length, the first control valve is controlled to be connected. The sixth preset time length can be 1 min, 1.5 min or 2 min, etc.

[0124] After the first control valve is controlled to be connected, the overheat degree of the compressor is obtained again, and the connection or disconnection of the first control valve is controlled based on the overheat degree. If the first control valve is controlled to be disconnected, the connection or disconnection of the first control valve is controlled again based on the valve closing time length of the first control valve. The connection or disconnection of the first control valve is controlled in the above-mentioned manner until the current refrigeration program ends. In this way, in the entire refrigeration process, the purity of the liquid refrigerant input into the indoor heat exchanger can be maximized, the mixed gaseous refrigerant can be reduced, the noise of the first throttling device can be reduced, the actual maximum flow of the first throttling device can be consistent with the design value, and the heat exchange performance and energy efficiency of the indoor heat exchanger can be improved.

[0125] In order to facilitate understanding of the control method of the air conditioning system provided by the embodiments of the present application, the following will be described with reference to the drawings. Figure 12 The control process of the first control valve in the heating condition is shown in the case where the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the inlet of the compressor. Figure 12 As shown, after the heating program starts, the first control valve is first disconnected, and it is judged whether the valve closing time length reaches a first preset time length. If not, the first control valve is continuously kept disconnected. If yes, the first control valve is controlled to be connected, and it is judged whether the overheat degree of the return gas of the compressor is lower than a threshold. If not, the first control valve is continuously kept connected. If yes, the first control valve is disconnected, and it is judged whether the flow distribution of each flow path of the outdoor heat exchanger is uniform, or it is judged whether the valve closing time length of the first control valve is less than a second preset time length. If yes, the first control valve is continuously kept disconnected. If not, the first control valve is connected.

[0126] The judgment process of judging whether the flow distribution of each flow path of the outdoor heat exchanger is uniform is as shown in Figure 13As shown, the first control valve is opened, and the average heat exchange coefficient of the outdoor heat exchanger in the preset time period after the valve is closed is recorded. It is determined whether the heat exchange coefficient of the outdoor heat exchanger is less than the product of the preset attenuation coefficient and the average heat exchange coefficient and lasts for a certain time period. If yes, it is determined that the flow distribution is uneven, and if no, it is determined that the flow distribution is even.

[0127] Figure 14 As shown, the control process of the first control valve in the heating mode is shown in the case where the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the inlet of the compressor. As shown in the figure, Figure 14 As shown, after the heating program starts, the first control valve is first opened, and it is determined whether the valve closing time period reaches the first preset time period. If no, the first control valve is continuously kept open. If yes, the first control valve is controlled to be connected, and it is determined whether the suction superheat of the compressor is lower than the threshold value. If no, the first control valve is continuously kept connected. If yes, the first control valve is closed, and it is determined whether the valve closing time period of the first control valve is less than the second preset time period. If yes, the first control valve is continuously kept closed. If no, the first control valve is connected.

[0128] Figure 15 As shown, the control process of the first control valve in the heating mode is shown in the case where the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the inlet of the compressor. As shown in the figure, Figure 15 As shown, after the heating program starts, the first control valve is first opened, and it is determined whether the valve closing time period reaches the first preset time period. If no, the first control valve is continuously kept open. If yes, the first control valve is controlled to be connected, and it is determined whether the suction superheat of the compressor is lower than the threshold value. If no, the first control valve is continuously kept connected. If yes, the first control valve is closed, and it is determined whether the valve closing time period of the first control valve is less than the second preset time period. If yes, the first control valve is continuously kept closed. If no, the first control valve is connected.

[0129] Figure 16 As shown, the control process of the first control valve in the heating mode is shown in the case where the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the inlet of the compressor. As shown in the figure, Figure 16 As shown, after the heating program starts, the first control valve is first opened, and it is determined whether the valve closing time period reaches the first preset time period. If no, the first control valve is continuously kept open. If yes, the first control valve is controlled to be connected, and it is determined whether the suction superheat of the compressor is lower than the threshold value. If no, the first control valve is continuously kept connected. If yes, the first control valve is closed, and it is determined whether the valve closing time period of the first control valve is less than the second preset time period. If yes, the first control valve is continuously kept closed. If no, the first control valve is connected.

[0130] In the embodiments of the present application, whether the distribution of the refrigerant between the flow paths of the outdoor heat exchanger is uniform is determined during the heating process, and the connection or disconnection of the first control valve is controlled, so that the uniform distribution of the refrigerant between the flow paths of the outdoor heat exchanger is maintained to the greatest extent, thereby improving the heat exchange performance and energy efficiency of the air conditioning system. By flexibly controlling the connection or disconnection of the first control valve, the gaseous refrigerant input into the outdoor heat exchanger and the case where the liquid refrigerant is directly output from the third delivery pipe of the gas-liquid separator can be reduced, which helps to reduce the case where the suction superheat or discharge superheat of the compressor is too low. During the refrigeration process, the purity of the liquid refrigerant input into the indoor heat exchanger can be maximized, and the mixed gaseous refrigerant can be reduced, thereby reducing the noise of the first throttling device, making the actual maximum flow of the first throttling device consistent with the design value, and improving the heat exchange performance and energy efficiency of the indoor heat exchanger.

[0131] The embodiments of the present application provide a control device of an air conditioning system, which is used to execute the control method of the air conditioning system provided in any of the above embodiments. As shown in the figure, the device comprises: Figure 17

[0132] The detection module 201 is configured to detect whether the distribution of the refrigerant between the flow paths of the outdoor heat exchanger is uniform during the heating process, and obtain a detection result.

[0133] The recording module 202 is configured to record the superheat of the compressor and the valve closing time length of the first control valve each time the valve is closed.

[0134] The control module 203 is configured to control the connection or disconnection of the first control valve based on the detection result, the superheat of the compressor and the valve closing time length of the first control valve.

[0135] The detection module 201 is configured to acquire the average heat exchange coefficient of the outdoor heat exchanger within a first preset time length in the case where the first control valve is disconnected; determine that the detection result is that the distribution of the refrigerant between the flow paths of the outdoor heat exchanger is not uniform based on the fact that the heat exchange coefficients of the outdoor heat exchanger within a second preset time length are all less than the product of the average heat exchange coefficient and a preset attenuation coefficient; and determine that the detection result is that the distribution of the refrigerant between the flow paths of the outdoor heat exchanger is uniform based on the fact that there is a case where the heat exchange coefficients of the outdoor heat exchanger within the second preset time length are greater than or equal to the product.

[0136] The recording module 202 is configured to record the suction superheat of the compressor in the case where the second end of the first control valve is connected to the pipeline between the second end of the outdoor heat exchanger and the inlet of the compressor; or record the discharge superheat of the compressor in the case where the second end of the first control valve is connected to the medium-pressure cavity of the compressor.

[0137] ​The control module 203 is configured to detect the heating program start instruction, control the first control valve to be closed, control the first control valve to be connected based on the first control valve being closed for a third preset time length, control the first control valve to be closed based on the overheat degree of the compressor being lower than a first preset temperature threshold, and control the first control valve to be connected based on the detection result indicating uneven flow distribution and / or the first control valve being closed for a fourth preset time length this time.

[0138] The control module 203 is further configured to, in the refrigeration working condition, record the overheat degree of the compressor and the valve closing time length of the first control valve each time the valve is closed, and control the first control valve to be connected or closed based on the overheat degree or the valve closing time length of the first control valve.

[0139] The control module 203 is further configured to detect the heating program start instruction, control the first control valve to be closed, control the first control valve to be connected based on the first control valve being closed for a third preset time length, control the first control valve to be closed based on the overheat degree of the compressor being lower than a first preset temperature threshold, and control the first control valve to be connected based on the detection result indicating uneven flow distribution and / or the first control valve being closed for a fourth preset time length this time.

[0140] The control device of the air conditioning system provided in the above embodiments of the present application has the same beneficial effects as the method adopted, run or implemented by the application program stored therein, based on the same inventive concept as the control method of the air conditioning system provided in the embodiments of the present application.

[0141] The embodiments of the present application further provide a control device of an air conditioning system for executing the control method of the air conditioning system. The control device of the air conditioning system can be a controller in the air conditioning system. Please refer to Figure 18 which shows a schematic diagram of a control device of an air conditioning system provided by some embodiments of the present application. As shown in Figure 18 The control device of the air conditioning system 40 includes a processor 400, a memory 401, a bus 402 and a communication interface 403, the processor 400, the communication interface 403 and the memory 401 are connected through the bus 402, the memory 401 stores a computer program capable of running on the processor 400, and the processor 400 runs the computer program to execute the control method of the air conditioning system provided in any of the preceding embodiments of the present application.

[0142] The memory 401 can include a high-speed random access memory (RAM) and can also include a non-volatile memory, such as at least one disk memory. The communication connection between the apparatus network element and at least one other network element is realized through at least one communication interface 403 (which can be wired or wireless), and the Internet, a wide area network, a local network, a metropolitan area network, etc. can be used.

[0143] The bus 402 can be an ISA bus, a PCI bus, an EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. The memory 401 is used to store programs, and the processor 400 executes the programs after receiving execution instructions. The control method of the air conditioning system disclosed in any of the embodiments of the present application can be applied to the processor 400 or implemented by the processor 400.

[0144] The processor 400 can be an integrated circuit chip with signal processing capability. In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in the processor 400 or the instruction in the form of software. The processor 400 described above can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a ready-to-program gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. Each method, step and logic block disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as a hardware code processor for execution, or a combination of hardware and software modules in the code processor for execution. The software module can be located in a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, a register, etc. The storage medium in the art. The storage medium is located in the memory 401, and the processor 400 reads the information in the memory 401, and combines the hardware to complete the steps of the above method.

[0145] The control device of the air conditioning system provided in the embodiments of the present application and the control method of the air conditioning system provided in the embodiments of the present application have the same beneficial effects as the method they use, run or implement.

[0146] The embodiment of the present application further provides a computer readable storage medium corresponding to the control method of the air conditioning system provided by the foregoing embodiment, please refer to Figure 19 The computer readable storage medium shown in the embodiment is an optical disc 30, and a computer program (i.e., a program product) is stored on the optical disc 30, and the computer program performs the control method of the air conditioning system provided by any of the foregoing embodiments when being run by a processor.

[0147] It should be noted that examples of the computer readable storage medium can further include, but are not limited to, a phase change memory (PRAM), a static random access memory (SRAM), a dynamic random access memory (DRAM), other types of random access memory (RAM), a read only memory (ROM), an electrically erasable programmable read only memory (EEPROM), a flash memory, or other optical or magnetic storage medium, which are not listed one by one here.

[0148] The computer readable storage medium provided by the foregoing embodiment of the present application and the control method of the air conditioning system provided by the embodiment of the present application have the same beneficial effects as the method adopted, run or implemented by the application program stored therein.

[0149] It should be noted that:

[0150] In the specification provided herein, a large number of specific details are described. However, it can be understood that the embodiments of the present application can be practiced without these specific details. In some examples, well-known structures and techniques are not shown in detail in order not to obscure the understanding of the present specification.

[0151] Similarly, it should be understood that, in order to simplify the present application and help understand one or more of the various inventive aspects, in the above description of the exemplary embodiments of the present application, various features of the present application are sometimes grouped together in a single embodiment, figure, or description thereof. However, this method of disclosure should not be interpreted as reflecting the intention that the claimed present application requires more features than those explicitly recited in each claim. Rather, the inventive aspects are based on less than all of the features of the single embodiment disclosed above, as reflected in the claims below. Therefore, the claims following the detailed description are hereby expressly incorporated into the detailed description, and each claim itself is a separate embodiment of the present application.

[0152] Furthermore, those skilled in the art will recognize that, in the following claims, the singular form "a" and "the" include plural references unless the context clearly dictates otherwise. As such, the claims following depend from claim 1 should be interpreted as including the plural forms as well.

[0153] The above description is only preferred specific embodiments of the present application, but the protection scope of the present application is not limited thereto, any changes or replacements within the technical scope disclosed by the present application can be easily thought by any person skilled in the art, and should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An air conditioning system comprising a compressor (1), an outdoor heat exchanger (2), a gas-liquid separator (3), an indoor heat exchanger (4), a four-way valve (13) and a first throttling device (17), characterized in that, the first throttling device (17) is arranged between a first delivery pipe (i) of the gas-liquid separator (3) and a second end (42) of the indoor heat exchanger (4), a second delivery pipe (j) of the gas-liquid separator (3) is in communication with a first end (210) of the outdoor heat exchanger (2); a third delivery pipe (k) of the gas-liquid separator (3) is connected to a gas return pipe between the four-way valve (13) and the compressor (1) and is in communication with the gas return pipe; or the third delivery pipe (k) is connected to a first chamber (14) of the compressor (1) and is in communication with the first chamber (14); the gas-liquid separator (3) separates the refrigerant from the first delivery pipe (i) or the second delivery pipe (j) into gaseous refrigerant and liquid refrigerant, and the separated gaseous refrigerant is output from the third delivery pipe (k); the system further comprises a first control valve (5), a first end of the first control valve (5) is connected to the third delivery pipe (k), and a second end of the first control valve (5) is connected to the gas return pipe or the first chamber (14); in a heating operating condition, the communication or disconnection of the first control valve (5) is controlled based on a detection result, a recorded superheat degree of the compressor (1) and a recorded valve closing time length of the first control valve (5), and the detection result is obtained according to whether the detection of the refrigerant shunting between the flow paths of the outdoor heat exchanger (2) is uniform.

2. The air conditioning system according to claim 1, characterized in that, the first delivery pipe (i) is arranged on a side wall of the gas-liquid separator (3), the position of the first delivery pipe (i) is lower than that of the third delivery pipe (k) and higher than that of the second delivery pipe (j); the port of the second delivery pipe (j) is oriented so that the refrigerant input from the second delivery pipe (j) can be sprayed onto the side wall and / or the bottom surface of the gas-liquid separator (3).

3. The air conditioning system of claim 1, wherein, The first chamber (14) comprises a medium-pressure chamber of the compressor (1).

4. The air conditioning system of claim 1, wherein, The system further comprises a second control valve (8), a third control valve (9), a fourth control valve (10) and a fifth control valve (11); the second control valve (8) has a first end and a second end, the first end of the second control valve (8) is located between the first delivery pipe (i) and the fifth control valve (11), and the second end of the second control valve (8) is located between the third control valve (9) and the first throttling device (17); the fourth control valve (10) has a first end and a second end, the first end of the fourth control valve (10) is located between the third control valve (9) and the second delivery pipe (j), and the second end of the fourth control valve (10) is located between the first end of the outdoor heat exchanger (2) and the fifth control valve (11).

5. The air conditioning system according to claim 4, characterized in that, In the heating mode, the second control valve (8) and the fourth control valve (10) are connected, the third control valve (9) and the fifth control valve (11) are disconnected, the refrigerant from the indoor heat exchanger (4) enters the separation cavity of the gas-liquid separator (3) from the first delivery pipe (i) through the second control valve (8), and the separated liquid refrigerant flows out from the second delivery pipe (j) and enters the outdoor heat exchanger (2) through the fourth control valve (10).

6. The air conditioning system according to claim 4, wherein, In the cooling mode, the third control valve (9) and the fifth control valve (11) are connected, the second control valve (8) and the fourth control valve (10) are disconnected, the refrigerant from the outdoor heat exchanger (2) enters the separation cavity of the gas-liquid separator (3) from the first delivery pipe (i) through the fifth control valve (11), and the separated liquid refrigerant flows out from the second delivery pipe (j) and enters the indoor heat exchanger (4) through the third control valve (9).

7. The air conditioning system of claim 2, wherein The port of the second delivery pipe (j) is directed towards the bottom surface or the side wall, and the included angle between the port of the second delivery pipe (j) and the normal line of the bottom surface is greater than or equal to 0° and less than a preset angle, and the preset angle is the obtuse angle between the normal line of the bottom surface and the port of the first delivery pipe (i).

8. The air conditioning system of claim 2 or 7, wherein The port of the third delivery pipe (k) is directed towards the top surface of the gas-liquid separator (3) at an included angle within [0°, 90°]; and / or, The port of the first delivery pipe (i) is directed parallel to the top surface or inclined towards the bottom surface at an inclination angle within (0°, 10°].

9. The air conditioning system of claim 1, wherein, The air conditioning system further comprises a low-pressure tank (12); The four-way valve (13) is connected to the compressor (1), the first end (41) of the indoor heat exchanger (4), the second end (220) of the outdoor heat exchanger (2), and the inlet of the low-pressure tank (12), respectively; and the outlet of the low-pressure tank (12) is connected to the inlet of the compressor (1).

10. The air conditioning system of claim 1, wherein, The air conditioning system further comprises a first distributor (15) and a second distributor (16); The manifold end of the first distributor (15) is connected to the second delivery pipe (j), and each branch end of the first distributor (15) is connected to the first end of each flow path in the outdoor heat exchanger (2), respectively. The manifold end of the second distributor (16) is connected to the four-way valve (13), and each branch end of the second distributor (16) is connected to the second end of each flow path in the outdoor heat exchanger (2), respectively.

11. The air conditioning system of claim 10, wherein, The first distributor (15) and / or the second distributor (16) is a distributor in the form of a flute-shaped pipe or a capillary tube.

12. The air conditioning system of claim 3, wherein, The air conditioning system further comprises a second throttling device (18) located between the third delivery pipe (k) and the first control valve (5).

13. A control method of an air conditioning system, characterized by, The control method of the air conditioning system is applied to the air conditioning system of any one of claims 1-12, and the method comprises: In the heating operating mode, whether the refrigerant is evenly distributed among the flow paths of the outdoor heat exchanger (2) is detected to obtain a detection result; The superheat of the compressor (1) and the valve closing duration of the first control valve (5) each time are recorded; Based on the detection result, the superheat of the compressor (1) and the valve closing duration of the first control valve (5), the first control valve (5) is controlled to be connected or disconnected.

14. The method of claim 13, wherein, The detection of whether the refrigerant is evenly distributed among the flow paths of the outdoor heat exchanger (2) obtains a detection result, comprising: In the case that the first control valve (5) is disconnected, the average heat exchange coefficient of the outdoor heat exchanger (2) within a first preset time is obtained; Based on the fact that the heat exchange coefficients of the outdoor heat exchanger (2) within a second preset time are all less than the product of the average heat exchange coefficient and a preset attenuation coefficient, it is determined that the detection result is that the refrigerant is not evenly distributed among the flow paths of the outdoor heat exchanger (2); Based on the fact that the heat exchange coefficients of the outdoor heat exchanger (2) within the second preset time are greater than or equal to the product, it is determined that the detection result is that the refrigerant is evenly distributed among the flow paths of the outdoor heat exchanger (2).

15. The method of claim 13, wherein, The recording of the superheat of the compressor (1) comprises: In the case that the first control valve (5) is connected to the gas return pipeline between the four-way valve (13) and the compressor (1), the gas return superheat of the compressor (1) is recorded; or, In the case that the first control valve (5) is connected to the first chamber (14) of the compressor (1), the exhaust superheat of the compressor (1) is recorded.

16. The method of claim 13, wherein, The control of the first control valve (5) to be connected or disconnected based on the detection result, the superheat of the compressor (1) and the valve closing duration of the first control valve (5) comprises: When a heating program start instruction is detected, the first control valve (5) is controlled to be disconnected; When the valve closing duration of the first control valve (5) reaches a third preset time, the first control valve (5) is controlled to be connected; When the superheat of the compressor (1) is lower than a first preset temperature threshold, the first control valve (5) is controlled to be disconnected; When the detection result indicates uneven distribution, and / or the valve closing duration of the first control valve (5) this time reaches a fourth preset time, the first control valve (5) is controlled to be connected.

17. The method according to any one of claims 13-16, characterized by, The method further comprises: In the refrigeration operating mode, the superheat of the compressor (1) and the valve closing duration of the first control valve (5) each time are recorded; Based on the superheat or the valve closing duration of the first control valve (5), the first control valve (5) is controlled to be connected or disconnected.

18. The method of claim 17, wherein, The control of the first control valve (5) to be connected or disconnected based on the superheat or the valve closing duration of the first control valve (5) comprises: When a refrigeration program start instruction is detected, the first control valve (5) is controlled to be disconnected; When the valve closing duration of the first control valve (5) reaches a fifth preset time, the first control valve (5) is controlled to be connected; When the superheat of the compressor (1) is lower than a second preset temperature threshold, the first control valve (5) is controlled to be disconnected; The first control valve (5) is controlled to be communicated based on that the valve closing time length of the current disconnection of the first control valve (5) reaches a sixth preset time length.

19. A control device for the air conditioning system according to any one of claims 1 to 12, said device comprising a memory, a processor and a computer program stored on said memory and executable on said processor, characterized in that, The processor executes the computer program to implement the method of any one of claims 13-18.

20. A computer readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to implement the method of any one of claims 13-18.

Images