Air conditioning system and control method thereof

Abstract

The application discloses an air conditioning system and a control method thereof, relates to the technical field of air conditioners, and aims to solve the problem that the air conditioner is prone to frosting. The application comprises a compressor and a refrigerant main circuit, wherein the refrigerant main circuit is sequentially connected with an indoor heat exchanger, a throttling device and an outdoor heat exchanger assembly in series; the outdoor heat exchanger assembly comprises a first outdoor heat exchanger and a second outdoor heat exchanger which are connected in parallel with each other; a first control valve is arranged on the refrigerant main circuit; a second control valve is arranged on a pipeline between the first outdoor heat exchanger and the compressor and is connected in parallel with the second outdoor heat exchanger; a third control valve is arranged on a pipeline between the second outdoor heat exchanger and the throttling device and is connected in parallel with the first outdoor heat exchanger; one end of a connecting branch is communicated with the second control valve; the other end of the connecting branch is communicated with the third control valve; the second control valve controls the first outdoor heat exchanger to be communicated with the compressor or the connecting branch; and the third control valve controls the second outdoor heat exchanger to be communicated with the connecting branch or the throttling device.

Description

TECHNICAL FIELD

[0001] The present application relates to the air conditioning technical field, and especially relates to an air conditioning system and a control method thereof. BACKGROUND

[0002] Air conditioner is a common household appliance, which is composed of refrigeration compressor, condenser, capillary, evaporator, electromagnetic reversing valve, filter and refrigerant to realize refrigeration or heating purpose.

[0003] The existing air conditioner is prone to frost formation on the outdoor heat exchanger during heating operation in winter, and frequent defrosting is required. The indoor heating is stopped during the defrosting process, which will cause the indoor comfort to be poor. SUMMARY

[0004] The present application provides an air conditioning system and a control method thereof, which is used to solve the problem of frost formation in the prior art.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical scheme:

[0006] In a first aspect, the present application provides an air conditioning system, comprising: a compressor; a refrigerant main circuit, the refrigerant main circuit connects the exhaust port of the compressor and the suction port of the compressor as a circuit, and the refrigerant main circuit is sequentially connected with an indoor heat exchanger, a throttling device and an outdoor heat exchanger assembly, the outdoor heat exchanger assembly comprises a first outdoor heat exchanger and a second outdoor heat exchanger which are connected in parallel with each other; a first control valve, the first control valve is installed on the refrigerant main circuit, and the first control valve is used to control the exhaust port of the compressor to communicate with the outdoor heat exchanger assembly, the suction port of the compressor to communicate with the indoor heat exchanger, or the exhaust port of the compressor to communicate with the indoor heat exchanger, and the suction port of the compressor to communicate with the outdoor heat exchanger assembly; a connecting branch; a second control valve, the second control valve is installed on the pipeline between the first outdoor heat exchanger and the compressor, and is connected in parallel with the second outdoor heat exchanger; a third control valve, the third control valve is installed on the pipeline between the second outdoor heat exchanger and the throttling device, and is connected in parallel with the first outdoor heat exchanger, one end of the connecting branch communicates with the second control valve, and the other end of the connecting branch communicates with the third control valve, the second control valve is used to control the first outdoor heat exchanger to communicate with the compressor or the connecting branch, and the third control valve is used to control the second outdoor heat exchanger to communicate with the connecting branch or the throttling device.

[0007] In some possible embodiments of the present application, the air conditioning system further comprises a heat recovery branch and a heat recovery device, the heat recovery branch is connected between the compressor and the throttling device in parallel with the indoor heat exchanger; the heat recovery device comprises a first heat exchange flow path and a second heat exchange flow path which exchange heat with each other, the first heat exchange flow path is connected to the pipeline between the outdoor heat exchanger assembly and the throttling device, and the second heat exchange flow path is connected to the heat recovery branch, so that heating defrosting can be performed simultaneously and liquid hammer can be prevented.

[0008] In some possible embodiments of the present application, the air conditioning system further comprises a first regulating valve, the first regulating valve is installed on the heat recovery branch and located between the second heat exchange flow path of the heat recovery device and the throttling device.

[0009] In some possible embodiments of the present application, the air conditioning system further comprises a second regulating valve, the second regulating valve is installed on the heat recovery branch and located between the second heat exchange flow path of the heat recovery device and the compressor.

[0010] In the second aspect, the present application provides a control method for the air conditioning system, comprising the following steps: when a heating control signal is received, the first control valve controls the exhaust port of the compressor to communicate with the indoor heat exchanger, the suction port of the compressor to communicate with the outdoor heat exchanger assembly, the second control valve controls the first outdoor heat exchanger to communicate with the suction port of the compressor, and the third control valve controls the second outdoor heat exchanger to communicate with the throttling device; when a refrigeration control signal is received, the first control valve controls the exhaust port of the compressor to communicate with the outdoor heat exchanger assembly, the suction port of the compressor to communicate with the indoor heat exchanger, the second control valve controls the first outdoor heat exchanger to communicate with the connecting branch, and the third control valve controls the second outdoor heat exchanger to communicate with the connecting branch.

[0011] In some possible embodiments of the present application, the air conditioning system further comprises a first regulating valve and a second regulating valve, the first regulating valve is installed on the regenerative branch and located between the second regenerative flow path of the regenerator and the throttling device, the second regulating valve is installed on the regenerative branch and located between the second regenerative flow path of the regenerator and the compressor, and the control method further comprises: when it is detected that the air conditioning system meets the defrosting condition, the first control valve controls the exhaust port of the compressor to communicate with the indoor heat exchanger, the suction port of the compressor to communicate with the outdoor heat exchanger assembly, the second control valve controls the first outdoor heat exchanger to communicate with the suction port of the compressor, the third control valve controls the second outdoor heat exchanger to communicate with the throttling device, and the first regulating valve and the second regulating valve are opened; when it is detected that the air conditioning system meets the defrosting stop condition, the first regulating valve and the second regulating valve are closed.

[0012] In some possible embodiments of the present application, after the first regulating valve and the second regulating valve are opened, the control method of the air conditioning system further comprises: when it is detected that the refrigerant pressure at the opening close to the compressor end of the regenerative branch is different from the refrigerant pressure at the opening close to the compressor end of the indoor heat exchanger, the opening degree of the first regulating valve is adjusted.

[0013] In some possible embodiments of the present application, the control method of the air conditioning system further comprises: after receiving the refrigeration control signal, when it is detected that the suction superheat degree of the air conditioning system is in a first preset temperature range and the duration that the suction superheat degree of the air conditioning system is in the first preset temperature range is greater than a preset time, the first regulating valve and the second regulating valve are opened; when the suction superheat degree of the air conditioning system is in a second preset temperature range, the first regulating valve is closed.

[0014] In some possible embodiments of the present application, after the first regulating valve and the second regulating valve are opened, the control method of the air conditioning system further comprises: when it is detected that the refrigerant pressure at the opening close to the first control valve end of the regenerative branch is different from the refrigerant pressure at the opening close to the throttling device end of the indoor heat exchanger, the opening degree of the second regulating valve is adjusted.

[0015] The air conditioning system and the control method thereof provided by the application, the air conditioning system comprises a compressor, an indoor heat exchanger, a throttling device and an outdoor heat exchanger assembly which are connected in series on a refrigerant main circuit, a first control valve on the refrigerant main circuit can control the exhaust port of the compressor to communicate with the outdoor heat exchanger assembly, the suction port of the compressor to communicate with the indoor heat exchanger, or control the exhaust port of the compressor to communicate with the indoor heat exchanger, the suction port of the compressor to communicate with the outdoor heat exchanger assembly, so as to realize switching of the refrigeration or heating operation mode of the air conditioner. Compared with the prior art, the outdoor heat exchanger assembly of the embodiment of the application comprises a first outdoor heat exchanger and a second outdoor heat exchanger which are connected in parallel, a second control valve, a third control valve and a connecting branch, the second control valve is installed on the pipeline between the first outdoor heat exchanger and the compressor and is connected in parallel with the second outdoor heat exchanger, the third control valve is installed on the pipeline between the second outdoor heat exchanger and the throttling device and is connected in parallel with the first outdoor heat exchanger, one end of the connecting branch communicates with the second control valve, and the other end of the connecting branch communicates with the third control valve. When the air conditioning system is in the heating mode, the first outdoor heat exchanger and the second outdoor heat exchanger are both on the low-pressure side of the refrigerant main circuit and are sensitive to the pressure loss of the refrigerant, so it is necessary to reduce the pressure loss of the refrigerant in the outdoor heat exchanger assembly as much as possible, therefore, the first outdoor heat exchanger can be controlled by the second control valve to communicate with the suction port of the compressor, the second outdoor heat exchanger can be controlled by the third control valve to communicate with the throttling device, that is, the first outdoor heat exchanger and the second outdoor heat exchanger are connected in parallel, the refrigerant from the throttling device is divided into two paths and enters the first outdoor heat exchanger and the second outdoor heat exchanger respectively, compared with the refrigerant from the throttling device entering the first outdoor heat exchanger and the second outdoor heat exchanger in sequence, the pressure loss of the single-path pipeline is reduced, the frosting problem of the outdoor heat exchanger assembly is alleviated, so that the comfort of the indoor temperature is not affected by frequent defrosting, the outlet pressure of the outdoor heat exchanger assembly and the heat exchange efficiency of the outdoor heat exchanger assembly are improved; when the air conditioning system is in the refrigeration mode, the first outdoor heat exchanger and the second outdoor heat exchanger are both on the high-pressure side of the refrigerant main circuit and are not sensitive to the pressure loss of the refrigerant, therefore, the first outdoor heat exchanger can be controlled by the second control valve to communicate with the connecting branch, the second outdoor heat exchanger can be controlled by the third control valve to communicate with the connecting branch, that is, the first outdoor heat exchanger and the second outdoor heat exchanger are connected in series, the refrigerant from the throttling device enters the first outdoor heat exchanger and the second outdoor heat exchanger in sequence, so that the heat exchange time of the refrigerant in the outdoor heat exchanger assembly is prolonged and the heat exchange efficiency is higher. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only represent some of the embodiments of the present application, and for those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0017] Figure 1 The refrigerant flow schematic diagram of the air conditioning system in the embodiment of the present application in the heating defrosting cycle;

[0018] Figure 2 The refrigerant flow schematic diagram of the air conditioning system in the embodiment of the present application in the heating cycle;

[0019] Figure 3 The refrigerant flow schematic diagram of the air conditioning system in the embodiment of the present application in the refrigeration anti-liquid strike cycle;

[0020] Figure 4 The refrigerant flow schematic diagram of the air conditioning system in the embodiment of the present application in the refrigeration cycle. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments only represent some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative effort fall within the protection scope of the present application.

[0022] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection; it can be directly connected, or indirectly connected through intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0023] In the description of the present application, "and / or" is only a description of the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects have an "or" relationship.

[0024] An air conditioner performs a refrigeration cycle of the air conditioner by using a compressor, a condenser, an expansion valve, and an evaporator. The refrigeration cycle includes a series of processes involving compression, condensation, expansion, and evaporation, and supplies refrigerant to air that has been adjusted and heat-exchanged.

[0025] The compressor compresses refrigerant gas in a high-temperature and high-pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

[0026] The expansion valve expands the liquid-phase refrigerant in a high-temperature and high-pressure state condensed in the condenser into a low-pressure liquid phase. The evaporator evaporates the refrigerant expanded in the expansion valve and returns refrigerant gas in a low-temperature and low-pressure state to the compressor. The evaporator can achieve a refrigeration effect by heat-exchanging with a material to be cooled using latent heat of evaporation of the refrigerant. Throughout the cycle, the air conditioner can adjust the temperature of an indoor space.

[0027] The outdoor unit of the air conditioner refers to a portion of the refrigeration cycle including the compressor and the outdoor heat exchanger, the indoor unit of the air conditioner includes the indoor heat exchanger, and the expansion valve can be provided in the indoor unit or the outdoor unit.

[0028] The indoor heat exchanger and the outdoor heat exchanger function as a condenser or an evaporator. When the indoor heat exchanger functions as a condenser, the air conditioner functions as a heater in a heating mode, and when the indoor heat exchanger functions as an evaporator, the air conditioner functions as a cooler in a cooling mode.

[0029] Reference Figure 1 and Figure 2The air conditioning system of the embodiment of the present application comprises a compressor 1, a refrigerant main circuit connecting the exhaust port of the compressor 1 and the suction port of the compressor 1 into a loop, an indoor heat exchanger 2, a throttling device 3 and an outdoor heat exchanger assembly 4 connected in series on the refrigerant main circuit, wherein the outdoor heat exchanger assembly 4 comprises a first outdoor heat exchanger 41 and a second outdoor heat exchanger 42 connected in parallel with each other, and a first control valve 5 is installed on the refrigerant main circuit, the first control valve 5 being used to control the communication between the exhaust port of the compressor 1 and the outdoor heat exchanger assembly 4, the communication between the suction port of the compressor 1 and the indoor heat exchanger 2, or the communication between the exhaust port of the compressor 1 and the indoor heat exchanger 2, and the communication between the suction port of the compressor 1 and the outdoor heat exchanger assembly 4. The air conditioning system further comprises a second control valve 6, a third control valve 7 and a connecting branch 11, wherein the second control valve 6 is installed on the pipeline between the first outdoor heat exchanger 41 and the compressor 1 and connected in parallel with the second outdoor heat exchanger 42, the third control valve 7 is installed on the pipeline between the second outdoor heat exchanger 42 and the throttling device 3 and connected in parallel with the first outdoor heat exchanger 41, one end of the connecting branch 11 is communicated with the second control valve 6, and the other end of the connecting branch 11 is communicated with the third control valve 7, the second control valve 6 is used to control the communication between the first outdoor heat exchanger 41 and the compressor 1 or the connecting branch 11, and the third control valve 7 is used to control the communication between the second outdoor heat exchanger 42 and the connecting branch 11 or the throttling device 3.

[0030] The air conditioning system of the embodiment of the present application comprises a compressor 1, an indoor heat exchanger 2, a throttling device 3, an outdoor heat exchanger assembly 4 connected in series on a refrigerant main circuit, and a first control valve 5 on the refrigerant main circuit, which can control the communication of the exhaust port of the compressor 1 with the outdoor heat exchanger assembly 4 and the communication of the suction port of the compressor 1 with the indoor heat exchanger 2, or control the communication of the exhaust port of the compressor 1 with the indoor heat exchanger 2 and the communication of the suction port of the compressor 1 with the outdoor heat exchanger assembly 4, so as to realize the switching of the refrigeration or heating operation mode of the air conditioner. Compared with the prior art, the outdoor heat exchanger assembly 4 of the embodiment of the present application comprises a first outdoor heat exchanger 41 and a second outdoor heat exchanger 42 connected in parallel with each other, a second control valve 6, a third control valve 7, and a connecting branch 11, the second control valve 6 is installed on the pipeline between the first outdoor heat exchanger 41 and the compressor 1 and is connected in parallel with the second outdoor heat exchanger 42, the third control valve 7 is installed on the pipeline between the second outdoor heat exchanger 42 and the throttling device 3 and is connected in parallel with the first outdoor heat exchanger 41, one end of the connecting branch 11 is communicated with the second control valve 6, and the other end of the connecting branch 11 is communicated with the third control valve 7. When the air conditioning system is in the heating mode, the first outdoor heat exchanger 41 and the second outdoor heat exchanger 42 are both on the low-pressure side of the refrigerant main circuit and are relatively sensitive to the pressure loss of the refrigerant, so it is necessary to reduce the pressure loss of the refrigerant in the outdoor heat exchanger assembly 4 as much as possible, and therefore the first outdoor heat exchanger 41 can be controlled to communicate with the suction port of the compressor 1 by the second control valve 6, and the second outdoor heat exchanger 42 can be controlled to communicate with the throttling device 3 by the third control valve 7, that is, the first outdoor heat exchanger 41 and the second outdoor heat exchanger 42 are connected in parallel, the refrigerant from the throttling device 3 is divided into two paths and enters the first outdoor heat exchanger 41 and the second outdoor heat exchanger 42 respectively, compared with the refrigerant from the throttling device 3 entering the first outdoor heat exchanger 41 and the second outdoor heat exchanger 42 in sequence, the pressure loss of the single-pass pipeline is reduced, the frosting problem of the outdoor heat exchanger assembly is alleviated, so as to avoid the frequent defrosting from affecting the comfort of the indoor temperature and improve the outlet pressure of the outdoor heat exchanger assembly and the heat exchange efficiency of the outdoor heat exchanger assembly; when the air conditioning system is in the refrigeration mode, the first outdoor heat exchanger 41 and the second outdoor heat exchanger 42 are both on the high-pressure side of the refrigerant main circuit and are not sensitive to the pressure loss of the refrigerant, so the first outdoor heat exchanger 41 can be controlled to communicate with the connecting branch 11 by the second control valve 6, and the second outdoor heat exchanger 42 can be controlled to communicate with the connecting branch 11 by the third control valve 7, that is, the first outdoor heat exchanger 41 and the second outdoor heat exchanger 42 are connected in series, the refrigerant from the throttling device 3 enters the first outdoor heat exchanger 41 and the second outdoor heat exchanger 42 in sequence, and the heat exchange time of the refrigerant in the outdoor heat exchanger assembly can be prolonged, and the heat exchange efficiency is relatively high.

[0031] In some possible embodiments of the present application, the air conditioning system further comprises a regenerative branch 12 and a regenerator 8, wherein the regenerative branch 12 is connected between the compressor 1 and the throttling device 3 in parallel with the indoor heat exchanger 2; the regenerator 8 comprises a first heat exchange flow path 81 and a second heat exchange flow path 82 which exchange heat with each other, the first heat exchange flow path 81 is connected to the pipeline between the outdoor heat exchanger assembly 4 and the throttling device 3, and the second heat exchange flow path 82 is connected to the regenerative branch 12. Figure 1 When the air conditioning system is in the heating defrosting mode, the high-temperature refrigerant in the second heat exchange flow path 82 of the regenerator 8 can increase the temperature of the refrigerant in the first heat exchange flow path 81 of the regenerator 8, so that the refrigerant entering the outdoor heat exchanger assembly 4 has a higher temperature, which can defrost the outdoor heat exchanger assembly 4. The air conditioning system can simultaneously perform the heating and defrosting processes, avoid the start and stop of the compressor 1, the frequent change of the state of the first control valve 5 (such as frequent reversing), the faster defrosting speed, the higher indoor comfort, and the longer service life of the air conditioning system. Figure 3 When the air conditioning system is in the refrigeration mode, the high-temperature refrigerant in the first heat exchange flow path 81 of the regenerator 8 can increase the temperature of the refrigerant in the second heat exchange flow path 82 of the regenerator 8, so that the temperature of the refrigerant entering the indoor heat exchanger 2 is reduced, i.e., the refrigerant entering the indoor heat exchanger 2 is pre-cooled, so that the heat exchange of the indoor heat exchanger 2 is more sufficient. After the refrigerant from the indoor heat exchanger 2 and the refrigerant from the second heat exchange flow path 82 of the regenerator 8 with a higher temperature are combined, the temperature of the combined refrigerant can be increased, and the amount of liquid refrigerant in the combined refrigerant can be reduced, thereby effectively avoiding the risk of liquid strike of the compressor 1 and prolonging the service life of the compressor 1.

[0032] In order to ensure that the pressure of the refrigerant from the regenerative branch 12 is the same as the pressure of the refrigerant from the indoor heat exchanger 2 in the heating mode of the air conditioning system to avoid the problem of refrigerant backflow caused by the pressure difference, the air conditioning system of the present application further comprises a first regulating valve 9 installed on the regenerative branch 12 and located between the second heat exchange flow path 82 of the regenerator 8 and the throttling device 3.

[0033] Similarly, in order to ensure that the pressure of the refrigerant from the regenerative branch 12 is the same as the pressure of the refrigerant from the indoor heat exchanger 2 in the refrigeration mode of the air conditioning system to avoid the problem of refrigerant backflow caused by the pressure difference, the air conditioning system of the present application further comprises a second regulating valve 10 installed on the regenerative branch 12 and located between the second heat exchange flow path 82 of the regenerator 8 and the compressor 1.

[0034] It should be noted that the first control valve 5 is an electronic reversing valve or an electromagnetic reversing valve, the second control valve 6 and the third control valve 7 are three-way control valves, the first regulating valve 9 and the second regulating valve 10 are electronic expansion valves, and the throttling device 3 is also an electronic expansion valve.

[0035] The embodiment of the present application also includes a control method for the air conditioning system in the above embodiment, comprising the following steps:

[0036] When receiving the heating control signal, the first control valve controls the discharge port of the compressor to communicate with the indoor heat exchanger, the suction port of the compressor to communicate with the outdoor heat exchanger assembly, the second control valve controls the first outdoor heat exchanger to communicate with the suction port of the compressor, and the third control valve controls the second outdoor heat exchanger to communicate with the throttling device.

[0037] When receiving the cooling control signal, the first control valve controls the discharge port of the compressor to communicate with the outdoor heat exchanger assembly, the suction port of the compressor to communicate with the indoor heat exchanger, the second control valve controls the first outdoor heat exchanger to communicate with the connecting branch, and the third control valve controls the second outdoor heat exchanger to communicate with the connecting branch.

[0038] The control method of the air conditioning system in the embodiment of the present application can achieve the same technical effects as the air conditioning system in the above embodiment, which will not be described here.

[0039] For the air conditioning system, the first regulating valve and the second regulating valve are further included, the first regulating valve is installed on the heat recovery branch and located between the second heat recovery flow path of the heat recovery device and the throttling device, and the second regulating valve is installed on the heat recovery branch and located between the second heat recovery flow path of the heat recovery device and the compressor, and the control method further comprises:

[0040] When detecting that the air conditioning system meets the defrosting condition, the first control valve controls the discharge port of the compressor to communicate with the indoor heat exchanger, the suction port of the compressor to communicate with the outdoor heat exchanger assembly, the second control valve controls the first outdoor heat exchanger to communicate with the suction port of the compressor, the third control valve controls the second outdoor heat exchanger to communicate with the throttling device, and the first regulating valve and the second regulating valve are opened.

[0041] When detecting that the air conditioning system meets the defrosting stop condition, the first regulating valve and the second regulating valve are closed.

[0042] The defrosting condition and the defrosting stop condition are both prior art. For example, the defrosting condition is that the temperature of the refrigerant in the first outdoor heat exchanger (or the second outdoor heat exchanger, or the first outdoor heat exchanger and the second outdoor heat exchanger) is less than a first preset defrosting temperature, and the duration that the temperature of the refrigerant in the first outdoor heat exchanger is less than the first preset defrosting temperature is greater than a first preset time. The defrosting stop condition is that the temperature of the refrigerant in the first outdoor heat exchanger (or the second outdoor heat exchanger, or the first outdoor heat exchanger and the second outdoor heat exchanger) is greater than a second preset defrosting temperature. The temperature sensor is installed in the outdoor heat exchanger assembly, and the temperature sensor is used to detect the temperature of the refrigerant in the first outdoor heat exchanger, or to detect the temperature of the refrigerant in the second outdoor heat exchanger, or to detect the temperature of the refrigerant in the first outdoor heat exchanger and the second outdoor heat exchanger. The air conditioning system further comprises a timer, and the timer is used to time the duration that the temperature of the refrigerant in the first outdoor heat exchanger (or the second outdoor heat exchanger, or the first outdoor heat exchanger and the second outdoor heat exchanger) is less than the first preset defrosting temperature.

[0043] The control step can realize simultaneous heating and defrosting, avoid starting and stopping of the compressor, have a faster defrosting speed, and have higher indoor comfort.

[0044] After the first adjusting valve and the second adjusting valve are opened, the control method further comprises the following steps of:

[0045] When the refrigerant pressure at the opening near the compressor on the regenerative branch is different from the refrigerant pressure at the opening near the compressor on the indoor heat exchanger, the opening degree of the first adjusting valve is adjusted.

[0046] The first pressure sensor is installed at the opening near the compressor on the regenerative branch, and the first pressure sensor can detect the refrigerant pressure at the opening near the compressor on the regenerative branch. The second pressure sensor is installed at the opening near the compressor on the indoor heat exchanger, and the second pressure sensor can detect the refrigerant pressure at the opening near the compressor on the indoor heat exchanger. By adjusting the opening degree of the first adjusting valve, the refrigerant pressure at the opening near the compressor on the regenerative branch can be ensured to be the same as the refrigerant pressure at the opening near the compressor on the indoor heat exchanger, thereby avoiding the problem of reverse flow of refrigerant.

[0047] Based on the above embodiment, the control method of the air conditioning system further comprises the following steps of:

[0048] After the refrigeration control signal is received, when the suction superheat degree of the air conditioning system is in a first preset temperature range, and the duration that the suction superheat degree of the air conditioning system is in the first preset temperature range is greater than a preset time, the first adjusting valve and the second adjusting valve are opened.

[0049] When the suction superheat of the air conditioning system is in the second preset temperature range, the first regulating valve is closed.

[0050] The suction superheat of the air conditioning system in the first preset temperature range can be that the suction superheat of the air conditioning system is lower than a preset temperature (such as 0℃), the suction superheat is equal to the suction temperature minus the saturation temperature corresponding to the suction pressure, the suction temperature is the temperature of the refrigerant entering the compressor, the suction temperature is detected by the temperature sensor installed at the suction port of the compressor, the suction pressure is detected by the pressure sensor installed at the suction port of the compressor, and the duration of the suction superheat of the air conditioning system being lower than the preset temperature is timed by the timer. The suction superheat of the air conditioning system in the second preset temperature range can be that the suction superheat of the air conditioning system is in the range of 0℃ to 5℃.

[0051] When the air conditioning system is in the refrigeration mode, the suction superheat of the air conditioning system is detected to be in the first preset temperature range, and the duration of the suction superheat of the air conditioning system being in the first preset temperature range is greater than a preset time (i.e. meeting the anti-liquid impact condition), by opening the first regulating valve and the second regulating valve (the air conditioning system enters the refrigeration anti-liquid impact mode), the temperature of the refrigerant flowing out of the second heat exchange channel of the regenerator and the refrigerant flowing out of the indoor heat exchanger after merging can be improved, the amount of liquid refrigerant in the merged refrigerant can be reduced, thereby avoiding the risk of effectively avoiding the injection of liquid refrigerant into the compressor, and prolonging the service life of the compressor. When the suction superheat of the air conditioning system is in the second preset temperature range (i.e. meeting the anti-liquid impact end condition), in combination with Figure 3 As shown in Figure 4 the first regulating valve 9 and the second regulating valve 10 are closed, so that the refrigerant enters the indoor heat exchanger.

[0052] Similarly, in the refrigeration anti-liquid impact mode of the air conditioning system, the control method further comprises, after opening the first regulating valve and the second regulating valve:

[0053] When the refrigerant pressure at the opening near one end of the first control valve on the regenerative branch is detected to be different from the refrigerant pressure at the opening near one end of the throttling device on the indoor heat exchanger, the opening degree of the second regulating valve is adjusted.

[0054] A third pressure sensor is installed at the opening near one end of the first control valve on the regenerative branch, which can detect the refrigerant pressure at the opening near one end of the first control valve on the regenerative branch. A fourth pressure sensor is installed at the opening near one end of the throttling device on the indoor heat exchanger, which can detect the refrigerant pressure at the opening near one end of the throttling device on the indoor heat exchanger. The control method can ensure that the refrigerant pressure at the opening near one end of the first control valve on the regenerative branch is the same as the refrigerant pressure at the opening near one end of the throttling device on the indoor heat exchanger by adjusting the opening degree of the second regulating valve, thereby avoiding the problem of refrigerant backflow.

[0055] It should be noted that for the above air conditioning system, when the defrosting stop condition is met, the first regulating valve and the second regulating valve are closed, a preset time (such as 3 minutes) is waited, and whether the defrosting condition is met is verified again, if met, the defrosting mode is entered again, so as to ensure the defrosting effect. Similarly, when the anti-liquid impact end condition is met, the first regulating valve and the second regulating valve are closed, a preset time (such as 3 minutes) is waited, and whether the anti-liquid impact condition is met is verified again, if met, the anti-liquid impact mode is entered again, so as to ensure the safety of the air conditioning system.

[0056] In the description of the present specification, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0057] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within 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, characterized in that, include: compressor; The refrigerant main circuit connects the compressor's discharge port and the compressor's suction port into a loop. An indoor heat exchanger, a throttling device, and an outdoor heat exchanger assembly are connected in series on the refrigerant main circuit. The outdoor heat exchanger assembly includes a first outdoor heat exchanger and a second outdoor heat exchanger connected in parallel. A first control valve is installed on the refrigerant main circuit. The first control valve is used to control the compressor's discharge port to connect with the outdoor heat exchanger assembly and the compressor's suction port to connect with the indoor heat exchanger, or to control the compressor's discharge port to connect with the indoor heat exchanger and the compressor's suction port to connect with the outdoor heat exchanger assembly. Connecting branch lines; The second control valve is installed on the pipeline between the first outdoor heat exchanger and the compressor, and is connected in parallel with the second outdoor heat exchanger; The third control valve is installed on the pipeline between the second outdoor heat exchanger and the throttling device and is connected in parallel with the first outdoor heat exchanger. One end of the connecting branch is connected to the second control valve, and the other end of the connecting branch is connected to the third control valve. The second control valve is used to control the first outdoor heat exchanger to connect with the compressor or the connecting branch, and the third control valve is used to control the second outdoor heat exchanger to connect with the connecting branch or the throttling device. A regenerative branch is connected between the compressor and the throttling device, and is connected in parallel with the indoor heat exchanger; The regenerator includes a first heat exchange flow path and a second heat exchange flow path that exchange heat with each other. The first heat exchange flow path is connected to the pipeline between the outdoor heat exchanger assembly and the throttling device, and the second heat exchange flow path is connected to the regenerator branch.

2. The air conditioning system according to claim 1, characterized in that, Also includes: A first regulating valve is installed on the regenerating branch and located between the second regenerating flow path of the regenerator and the throttling device.

3. The air conditioning system according to claim 1 or 2, characterized in that, Also includes: The second regulating valve is installed on the regenerating branch and located between the second regenerating flow path of the regenerator and the compressor.

4. A control method for an air conditioning system according to any one of claims 1 to 3, characterized in that, Includes the following steps: When a heating control signal is received, the first control valve controls the compressor's exhaust port to connect with the indoor heat exchanger and the compressor's suction port to connect with the outdoor heat exchanger assembly; the second control valve controls the first outdoor heat exchanger to connect with the compressor's suction port; and the third control valve controls the second outdoor heat exchanger to connect with the throttling device. When a refrigeration control signal is received, the first control valve controls the compressor's exhaust port to connect with the outdoor heat exchanger assembly and the compressor's suction port to connect with the indoor heat exchanger; the second control valve controls the first outdoor heat exchanger to connect with the connecting branch; and the third control valve controls the second outdoor heat exchanger to connect with the connecting branch.

5. The control method for the air conditioning system according to claim 4, characterized in that, The method also includes a first regulating valve and a second regulating valve. The first regulating valve is installed on the regenerating branch and located between the second regenerating flow path of the regenerator and the throttling device. The second regulating valve is installed on the regenerating branch and located between the second regenerating flow path of the regenerator and the compressor. The control method further includes: When the air conditioning system is detected to meet the defrosting conditions, the first control valve controls the compressor's exhaust port to connect with the indoor heat exchanger and the compressor's suction port to connect with the outdoor heat exchanger assembly; the second control valve controls the first outdoor heat exchanger to connect with the compressor's suction port; the third control valve controls the second outdoor heat exchanger to connect with the throttling device; and the first regulating valve and the second regulating valve are opened. When the air conditioning system is detected to meet the defrost stop condition, the first regulating valve and the second regulating valve are closed.

6. The control method for an air conditioning system according to claim 5, characterized in that, After opening the first regulating valve and the second regulating valve, the method further includes: When the refrigerant pressure at the end of the regenerator branch near the compressor is detected to be different from the refrigerant pressure at the end of the indoor heat exchanger near the compressor, the opening of the first regulating valve is adjusted.

7. The control method for an air conditioning system according to claim 5, characterized in that, Also includes: Upon receiving a cooling control signal, when the superheat of the air intake of the air conditioning system is detected to be within a first preset temperature range, and the duration of the superheat of the air intake of the air conditioning system within the first preset temperature range is greater than a preset time, the first regulating valve and the second regulating valve are opened. When the intake superheat of the air conditioning system is within the second preset temperature range, the first regulating valve is closed.

8. The control method for an air conditioning system according to claim 7, characterized in that, After opening the first regulating valve and the second regulating valve, the method further includes: When the refrigerant pressure at the opening near the first control valve on the regenerative branch is detected to be different from the refrigerant pressure at the opening near the throttling device on the indoor heat exchanger, the opening of the second regulating valve is adjusted.

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