Air conditioner and control method thereof

Abstract

The invention relates to the technical field of air conditioners, particularly provides an air conditioner and a control method thereof, and aims to solve the problem that an existing air conditioner cannot realize energy conservation and environmental protection while avoiding freezing of a chassis under a low-temperature heating working condition. In order to achieve the purpose, the air conditioner outdoor unit comprises a compressor, an outdoor heat exchanger and a secondary supercooling device, the secondary supercooling device is arranged at the bottom of the outdoor heat exchanger, an exhaust port of the compressor is communicated with an air inlet of an indoor unit, and an exhaust port of the indoor unit is communicated with an air inlet of the secondary supercooling device. The outdoor unit further comprises a base plate heat exchanger, the base plate heat exchanger is arranged on a base plate of the air conditioner, an air inlet of the base plate heat exchanger is communicated with the air outlet of the compressor, and an air outlet of the base plate heat exchanger is communicated with the air inlet of the outdoor heat exchanger. And a first valve is arranged between the air inlet of the chassis heat exchanger and the exhaust port of the compressor, so that the existing problems are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioners, and in particular provides an air conditioner and a control method thereof. Background Art

[0002] When the air conditioner is running in heating mode under low temperature environment, condensed water is easy to freeze on the chassis, blocking the drain port, causing the ice layer to pile up and break the fan, affecting its reliable operation. In order to prevent the air conditioner from icing and stacking during low temperature heating, the prior art usually lays an electric heating tube at the bottom of the condenser, and turns on the electric heating tube to de-ice during low temperature heating. However, in a low temperature environment, the chassis ice is stacked during the entire heating process, and the thickness is relatively large. If the power of the electric heating tube is too small, the de-icing effect cannot be achieved under extremely low temperature conditions; if the power of the electric heating tube is too high, on the one hand, it will cause the chassis to bake yellow, the paint to fall off, and cause chassis corrosion. On the other hand, it will also increase the energy consumption of the equipment, which does not meet the energy-saving requirements. Therefore, how to prevent the chassis from icing under low temperature heating conditions of the air conditioner, while saving energy and protecting the environment, has become a technical problem that needs to be solved urgently in this field.

[0003] In view of this, the art needs a new control method for an air conditioner and an air conditioner to solve the existing problems. Summary of the invention

[0004] The present invention aims to solve the above technical problem, that is, to solve the problem that the existing air conditioner cannot achieve energy saving and environmental protection while avoiding chassis icing under low-temperature heating conditions.

[0005] In a first aspect, the present invention provides an air conditioner, comprising an indoor unit and an outdoor unit, wherein the outdoor unit comprises a compressor, an outdoor heat exchanger and a secondary supercooling device, wherein the secondary supercooling device is arranged at the bottom of the outdoor heat exchanger, the exhaust port of the compressor is connected to the air inlet of the indoor unit, the exhaust port of the indoor unit is connected to the air inlet of the secondary supercooling device, the exhaust port of the secondary supercooling device is connected to the air inlet of the outdoor heat exchanger, the exhaust port of the outdoor heat exchanger is connected to the compressor, and the outdoor unit further comprises a chassis heat exchanger, wherein the chassis heat exchanger is arranged on the chassis of the air conditioner, the air inlet of the chassis heat exchanger is connected to the exhaust port of the compressor, the exhaust port is connected to the air inlet of the outdoor heat exchanger, and a first valve is arranged between the air inlet of the chassis heat exchanger and the exhaust port of the compressor.

[0006] In a specific embodiment of the above-mentioned air conditioner, an economizer, a first refrigerant pipeline and a second refrigerant pipeline are further arranged between the exhaust port of the indoor unit and the air inlet of the secondary supercooling device, the exhaust port of the indoor unit, the economizer and the secondary supercooling device are connected through the first refrigerant pipeline, the exhaust port of the indoor unit, the economizer and the air intake port of the compressor are connected through the second refrigerant pipeline, and a first electronic expansion valve is arranged on the second refrigerant pipeline, and the first electronic expansion valve is communicatively connected to the controller of the air conditioner.

[0007] In a specific embodiment of the above-mentioned air conditioner, the outdoor unit also includes an ambient temperature sensor for obtaining the ambient temperature and a high-pressure pressure sensor for obtaining the high-pressure pressure of the pipeline, and a second electronic expansion valve is arranged at the air inlet of the outdoor heat exchanger, and the ambient temperature sensor, the high-pressure pressure sensor and the second electronic expansion valve are all communicatively connected to the controller of the air conditioner.

[0008] In a specific embodiment of the above-mentioned air conditioner, the outdoor unit also includes a gas-liquid separator, a gas-oil separator and a four-way valve, the four-way valve includes a d port, an e port, a c port and an s port, the air inlet end of the gas-oil separator is connected to the exhaust port of the compressor, the air outlet end is connected to the indoor unit through the d port and the e port of the four-way valve, the return air end is connected to the compressor after passing through a capillary tube, the exhaust port of the outdoor heat exchanger is connected to the air inlet end of the gas-liquid separator through the c port and the s port of the four-way valve, and the exhaust end of the gas-liquid separator is connected to the compressor.

[0009] In a specific embodiment of the above-mentioned air conditioner, the outdoor unit also includes an injection reheat system for replenishing air to the compressor, the injection reheat system is communicatively connected to the controller of the air conditioner, and / or the chassis heat exchanger is laid flat on the outdoor heat exchanger side of the chassis.

[0010] In a second aspect, the present invention also provides a control method for an air conditioner, wherein the air conditioner is the air conditioner described in the above embodiment, and the control method includes: controlling the ambient temperature sensor to obtain the ambient temperature T0; comparing the ambient temperature T0 with the preset ambient temperature; and controlling the opening and closing state of the first valve based on the comparison result.

[0011] In the specific implementation of the above-mentioned control method for the air conditioner, the step of "controlling the opening and closing state of the first valve based on the comparison result" further includes: if T0>T1, then controlling the first valve to be closed; if T0≤T3, then controlling the first valve to be fully open.

[0012] In a specific implementation of the above-mentioned control method for an air conditioner, the control method further includes: obtaining the operating mode of the air conditioner; controlling the ambient temperature sensor to obtain the ambient temperature T0; comparing the ambient temperature T0 with the preset ambient temperature; controlling the opening and closing state of the first valve based on the comparison result and the operating mode of the above-mentioned air conditioner; if T2<T0≤T1, and the air conditioner is in the defrost mode, then controlling the first valve to be fully opened and closed after a first preset time delay after the defrost ends; if T3<T0≤T2, and the air conditioner is in the heating mode, then controlling the first valve to be half open; if T3<T0≤T2, and the air conditioner is in the defrost mode, then controlling the first valve to be fully opened.

[0013] In the specific implementation of the control method for the air conditioner, the outdoor unit further includes an air jet enthalpy increasing system for replenishing air to the compressor, and the air jet enthalpy increasing system is connected to the controller of the air conditioner in communication, and the step "if T0≤T3, then control the first valve to be fully opened" further includes: controlling the high-pressure pressure sensor to obtain the high-pressure pressure P of the pipeline d ; Compare the high pressure P of the pipeline d With the first preset high pressure P d0 The size of P d ≤P d0 , then the jet enthalpy increase system is controlled to start to supply air to the compressor.

[0014] In the specific implementation of the control method for the air conditioner, the control method further includes: obtaining the operating mode of the air conditioner; controlling the high-pressure pressure sensor to obtain the high-pressure pressure P of the pipeline; d ; Compare the high pressure P of the pipeline d and the second preset high pressure P d1 The size of P d ≥P d1 , and the air conditioner is in cooling or heating mode, the opening of the first valve is controlled to increase.

[0015] The technical effect of the present invention is as follows: the air conditioner of the present invention is provided with a secondary supercooling device at the bottom of the outdoor heat exchanger, and a chassis heat exchanger is provided at the bottom of the chassis, and the heat of the refrigerant in the air conditioning pipeline is used to heat the outdoor heat exchanger and the chassis through the secondary supercooling device and the chassis heat exchanger, respectively, thereby avoiding the ice formation on the outdoor heat exchanger and the chassis. At the same time, since the heat in the air conditioning pipeline is used as the heat source, compared with the method of using an electric heating element in the prior art, the energy consumption is reduced on the basis of meeting the deicing demand, and the problem that the existing air conditioner cannot achieve energy saving and environmental protection while avoiding the ice formation of the chassis under low temperature heating conditions is solved. In addition, since the present invention also provides a first valve between the air inlet of the chassis heat exchanger and the exhaust port of the compressor, the air conditioner of the present invention can choose whether to open the first valve to heat the chassis according to the actual use situation, and can also adjust the heating temperature of the chassis by controlling the angle of the first valve, which is more convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which:

[0017] Figure 1 is a structural schematic diagram of an air conditioner of the present invention;

[0018] Figure 2 is a main flow chart of a control method of embodiment 2 of the present invention;

[0019] Figure 3 is a flow chart of step S3 in embodiment 2 of the present invention;

[0020] Figure 4 is a main flow chart of another control method of embodiment 2 of the present invention;

[0021] Figure 5 is a flow chart of step S4 in the second embodiment of the present invention;

[0022] Figure 6 is a flow chart of Embodiment 3 of the present invention;

[0023] Figure 7 It is a flow chart of embodiment 4 of the present invention.

[0024] List of reference numerals:

[0025] 1. Air conditioner; 11. Indoor unit; 12. Outdoor unit; 121. Compressor; 122. Outdoor heat exchanger; 123. Secondary subcooling device; 124. Chassis heat exchanger; 125. First valve; 126. Economizer; 127. First refrigerant pipeline; 128. Second refrigerant pipeline; 1281. First electronic expansion valve; 129. Ambient temperature sensor; 12A. High-pressure pressure sensor; 12B. Second electronic expansion valve; 12C. Gas-liquid separator; 12D. Gas-oil separator; 12E. Four-way valve. DETAILED DESCRIPTION

[0026] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.

[0027] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0028] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] First, the existing air conditioner is described. When the air conditioner is running in heating mode under low temperature environment, condensed water is easy to freeze on the chassis, blocking the drain port, causing the ice layer to stack and break the fan, affecting its reliable operation. In order to prevent the air conditioner from icing and stacking during low temperature heating, the prior art usually lays an electric heating tube at the bottom of the condenser, and turns on the electric heating tube to de-ice during low temperature heating. However, in a low temperature environment, the chassis is stacked during the entire heating process, and the thickness is large. If the power of the electric heating tube is too small, the de-icing effect cannot be achieved under extremely low temperature conditions; if the power of the electric heating tube is too high, on the one hand, it will cause the chassis to bake yellow, the paint to fall off, and cause chassis corrosion. On the other hand, it will also increase the energy consumption of the equipment, which does not meet the energy-saving requirements. Therefore, how to prevent the chassis from icing under low temperature heating conditions, while saving energy and protecting the environment, has become a technical problem that needs to be solved in this field. For this purpose, the following implementation method is proposed.

[0030] Embodiment 1

[0031] like Figure 1 As shown, in order to solve the problem that the existing air conditioner 1 cannot achieve energy saving and environmental protection while avoiding chassis icing under low-temperature heating conditions, the air conditioner 1 of the present invention includes an indoor unit 11 and an outdoor unit 12, the indoor unit 11 includes an air pipe stop valve, a liquid pipe stop valve and two electronic expansion valves, the outdoor unit 12 includes a compressor 121, an air-oil separator 12D, an air-liquid separator 12C, a four-way valve 12E, an outdoor heat exchanger 122, a secondary supercooling device 123, an economizer 126 and a chassis heat exchanger 124, the secondary supercooling device 123 is arranged at the bottom of the outdoor heat exchanger 122, and the chassis heat exchanger 124 is laid flat on the outdoor heat exchanger 122 side of the bottom of the chassis.

[0032] The four-way valve 12E includes a d port, an e port, a c port, and an s port. The exhaust port of the compressor 121 is connected to the air inlet of the gas-oil separator 12D. The air outlet of the gas-oil separator 12D is connected to the gas pipe stop valve of the indoor unit 11 through the d port and the e port of the four-way valve 12E. The return air end of the gasoline separator is connected to the return liquid port of the compressor 121 after passing through a capillary tube. The refrigerant passes through the gas pipe stop valve and two electronic expansion valves of the indoor unit 11 in sequence and then is discharged from the liquid pipe stop valve to the indoor unit 11. An economizer 126 is provided between the liquid pipe stop valve of the indoor unit 11 and the air inlet of the secondary supercooling device 123, and a first refrigerant pipeline 127 and a second refrigerant pipeline 128 are provided between the liquid pipe stop valve and the secondary supercooling device 123. After the refrigerant is discharged from the liquid pipe stop valve of the indoor unit 11, it is connected to the economizer 126 and the secondary supercooling device 123 in sequence through the first refrigerant pipeline 127, and is connected to the economizer 126 and the air intake of the compressor 121 in sequence through the second refrigerant pipeline 128, and flows back to the compressor 121 for reheating and re-pressurization. A first electronic expansion valve 1281 is provided on the second refrigerant pipeline 128, and the first electronic expansion valve 1281 is connected in communication with the controller of the air conditioner 1. After the refrigerant in the first refrigerant pipeline 127 enters the secondary supercooling device 123, it enters the air inlet of the outdoor heat exchanger 122 from the exhaust port of the secondary supercooling device 123, and a second electronic expansion valve 12B is also provided at the air inlet of the outdoor heat exchanger 122, and the second electronic expansion valve 12B is connected in communication with the controller of the air conditioner 1. After the refrigerant flows out from the exhaust port of the outdoor heat exchanger 122, it passes through the c port and the s port of the four-way valve 12E and enters the gas-liquid separator 12C from the air inlet end of the gas-liquid separator 12C, and then flows back from the exhaust end of the gas-liquid separator 12C through the return liquid port of the compressor 121 to the compressor 121 for temperature and pressure increase. The outdoor unit 12 of the air conditioner 1 in this embodiment also includes a chassis heat exchanger 124, the air inlet of the chassis heat exchanger 124 is connected to the exhaust port of the compressor 121, the exhaust port of the chassis heat exchanger 124 is connected to the air inlet of the outdoor heat exchanger 122, and a first valve 125 is also provided between the air inlet of the chassis heat exchanger 124 and the exhaust port of the compressor 121.

[0033] In addition, the outdoor unit 12 of the air conditioner 1 in this embodiment also includes an ambient temperature sensor 129 for obtaining the ambient temperature, a high-pressure pressure sensor 12A for obtaining the high-pressure pressure of the pipeline, and an injection reheat system for replenishing air to the compressor 121. The ambient temperature sensor 129, the high-pressure pressure sensor 12A and the injection reheat system are all communicatively connected to the controller of the air conditioner 1.

[0034] In the case of adopting the above-mentioned embodiment, during the use of the air conditioner 1 of the present invention, when the air conditioner 1 is in a low-temperature heating condition, the first valve 125 is opened, and a part of the high-temperature and high-pressure refrigerant discharged from the compressor 121 can enter the chassis heat exchanger 124 to heat the chassis heat exchanger 124, and then when the temperature of the chassis heat exchanger 124 rises, the chassis can be heated and de-iced to prevent ice from forming on the bottom. The remaining refrigerant discharged from the compressor 121 passes through the d port and the e port of the four-way valve 12E and enters the indoor unit 11 to release heat indoors. After the heat release is completed, a part of the medium-temperature medium-pressure refrigerant passes through the first refrigerant pipeline 127 and the economizer 126 and enters the secondary supercooling device 123 to heat the secondary supercooling device 123. Then, when the temperature of the secondary supercooling device 123 rises, it can de-ice the outdoor heat exchanger 122. At the same time, the refrigerant after the heat exchange with the secondary supercooling device 123 passes through the second electronic expansion valve 12B and enters the outdoor heat exchanger 122 to evaporate, and then passes through the c port and the s port of the four-way valve 12E and enters the gas-liquid separator 12C, and then flows back to the compressor 121. On the other hand, another part of the medium-temperature medium-pressure refrigerant after the heat release of the indoor unit 11 passes through the second refrigerant pipeline 128 and the economizer 126 and the first electronic expansion valve 1281 and flows back to the compressor 121, thereby completing the refrigerant cycle.

[0035] The advantage of the above embodiment is that the air conditioner 1 of the present invention sets a secondary supercooling device 123 at the bottom of the outdoor heat exchanger 122, and sets a chassis heat exchanger 124 at the bottom of the chassis. The heat of the refrigerant in the air-conditioning pipeline is used to heat the outdoor heat exchanger 122 and the chassis through the secondary supercooling device 123 and the chassis heat exchanger 124, respectively, thereby avoiding ice formation on the outdoor heat exchanger 122 and the chassis. At the same time, since the heat in the air-conditioning pipeline is used as the heat source, compared with the method of using electric heating elements in the prior art, energy consumption is reduced on the basis of meeting the deicing requirements, thereby solving the problem that the existing air conditioner 1 cannot achieve energy saving and environmental protection while avoiding chassis icing under low-temperature heating conditions.

[0036] Embodiment 2

[0037] The present invention also provides a control method for an air conditioner 1, wherein the air conditioner 1 is the air conditioner 1 mentioned in the first embodiment. Figure 1-Figure 5 As shown, the control method includes:

[0038] S1, control the ambient temperature sensor 129 to obtain the ambient temperature T0;

[0039] S2, comparing the ambient temperature T0 with the preset ambient temperature;

[0040] S3. Control the opening and closing state of the first valve 125 based on the comparison result.

[0041] In the above steps, step S3 further comprises:

[0042] S31, if T0>T1, control the first valve 125 to close;

[0043] S32: If T0≤T3, control the first valve 125 to be fully open.

[0044] The control method also includes:

[0045] S0, obtaining the operating mode of the air conditioner 1;

[0046] S1, control the ambient temperature sensor 129 to obtain the ambient temperature T0;

[0047] S2, comparing the ambient temperature T0 with the preset ambient temperature;

[0048] S4, controlling the opening and closing state of the first valve 125 based on the comparison result and the operation mode of the air conditioner 1;

[0049] S41, if T2<T0≤T1, and the air conditioner 1 is in the defrosting mode, the first valve 125 is controlled to be fully opened and closed after a first preset time delay after the defrosting is completed;

[0050] S42, if T3<T0≤T2, and the air conditioner 1 is in the heating mode, control the first valve 125 to be half open;

[0051] S43: If T3<T0≤T2, and the air conditioner 1 is in the defrost mode, the first valve 125 is controlled to be fully opened.

[0052] In the case of adopting the above embodiment, the ambient temperature sensor 129 is first controlled to obtain the ambient temperature T0, and T0 is compared with the preset ambient temperature. If T0>T1 (for example, 4°C), it means that the ambient temperature is relatively high at this time, and the chassis will not freeze in any operating mode of the air conditioner. Therefore, the first valve 125 is controlled to be closed, and the condenser can be heated only by the secondary supercooling device 123. If T0≤T3 (for example, -18°C), it means that the ambient temperature is relatively low at this time, and the chassis may freeze in any operating mode of the air conditioner. Therefore, the first valve 125 is controlled to be fully opened at this time, so that the chassis heat exchanger 124 and the secondary supercooling device 123 heat the chassis and the outdoor heat exchanger 122 simultaneously and separately to avoid freezing. If -18℃<T0≤4℃, it is necessary to obtain the operating mode of the air conditioner 1, and compare the ambient temperature with the preset ambient temperature. If 0℃<T0≤4℃, and the air conditioner 1 is in the defrost mode, it means that the ambient temperature is low at this time. At the same time, due to the large amount of condensed water in the defrost mode, the risk of ice formation in the chassis is increased. Therefore, the first valve 125 is controlled to be fully opened to warm up the chassis to prevent it from freezing. When the defrost is completed, the amount of condensed water is relatively small. At this time, the first valve 125 can be closed after delaying for one minute to ensure that the chassis does not freeze. If -18℃<T0≤0℃, and the air conditioner 1 is in the heating mode, it means that the ambient temperature is relatively low at this time, but the amount of condensed water is not large, so the first valve 125 can be controlled to be half open. If -18℃<T0≤0℃, and the air conditioner 1 is in the defrost mode, the amount of condensed water increases due to defrosting at this time, so the first valve 125 is controlled to be fully opened to prevent the chassis from freezing. Therefore, the air conditioner 1 of the present invention can reasonably control the opening and closing and the opening angle of the first valve 125 according to the ambient temperature and the current operating mode of the air conditioner 1, so as to automatically control the heating temperature of the chassis heat exchanger 124, thereby preventing the chassis from freezing and ensuring low energy consumption of the equipment.

[0053] Embodiment 3

[0054] In this embodiment, the outdoor unit 12 further includes an air injection enthalpy increase system for supplying air to the compressor 121, and the air injection enthalpy increase system is communicatively connected to the controller of the air conditioner 1, such as Figure 6 As shown, after step S32, the following steps are also included:

[0055] S33, controlling the high pressure sensor 12A to obtain the high pressure Pd of the pipeline;

[0056] S34, comparing the high pressure Pd of the pipeline with the first preset high pressure Pd0;

[0057] S35 , if Pd≤Pd0, the injection enthalpy increase system is controlled to start to supply air to the compressor 121 .

[0058] When adopting the above-mentioned embodiment, the outdoor unit 12 of the air conditioner 1 of the present invention also includes a jet reheat system, which controls the high-pressure pressure sensor 12A to obtain the high-pressure pressure Pd of the pipeline, and compares Pd with the first preset pressure Pd0. If Pd≤Pd0, it means that the high-pressure pressure of the pipeline is too low at this time, so it is necessary to supplement the compressor 121 with air through the jet reheat system to ensure the high-pressure pressure of the pipeline.

[0059] Embodiment 4:

[0060] The above-mentioned embodiment 3 proposes a solution for handling when the pipeline high pressure is too low. When the air conditioner 1 is running in cooling or heating mode, the pipeline high pressure may be too high. For this reason, this embodiment is proposed. Figure 7 As shown, in this embodiment, the control method includes:

[0061] S0, obtaining the operating mode of the air conditioner 1;

[0062] S33, controlling the high pressure sensor 12A to obtain the high pressure Pd of the pipeline;

[0063] S36, comparing the high pressure Pd of the pipeline with the second preset high pressure Pd1;

[0064] S37 . If Pd≥Pd1 and the air conditioner 1 is in the cooling or heating mode, the opening of the first valve 125 is controlled to increase.

[0065] When adopting the above-mentioned implementation mode, the operating mode of the air conditioner 1 is first obtained, and the high-pressure pressure sensor 12A is controlled to obtain the high-pressure pressure Pd of the pipeline, and the size of Pd is compared with the second preset high-pressure pressure Pd1. If Pd≥Pd1, and the air conditioner 1 is in the cooling or heating mode, the pipeline is depressurized by controlling the opening of the first valve 125 to increase, thereby reducing the pressure in the pipeline and ensuring that the high-pressure pressure of the pipeline is not too large.

[0066] It should be noted that the above-mentioned implementation mode is only used to illustrate the principle of the present invention and is not intended to limit the scope of protection of the present invention. Without departing from the principle of the present invention, those skilled in the art can adjust the above-mentioned structure so that the present invention can be applied to more specific application scenarios.

[0067] Those skilled in the art can understand that the air conditioner 1 also includes some other well-known structures, such as a processor, a controller, a memory, etc., wherein the memory includes but is not limited to a random access memory, a flash memory, a read-only memory, a programmable read-only memory, a volatile memory, a non-volatile memory, a serial memory, a parallel memory or a register, etc., and the processor includes but is not limited to a CPLD / FPGA, a DSP, an ARM processor, a MIPS processor, etc. In order to unnecessarily obscure the embodiments of the present disclosure, these well-known structures are not shown in the drawings.

[0068] Although the various steps in the above embodiment are described in the above order, those skilled in the art can understand that in order to achieve the effect of this embodiment, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in a reverse order. For example, S0 and S1 can be executed simultaneously or one after the other. These simple changes are within the scope of protection of the present invention.

[0069] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. An air conditioner (1), characterized in that: The air conditioner (1) comprises an indoor unit (11) and an outdoor unit (12); the outdoor unit (12) comprises a compressor (121), an outdoor heat exchanger (122) and a secondary supercooling device (123); the secondary supercooling device (123) is arranged at the bottom of the outdoor heat exchanger (122); the exhaust port of the compressor (121) is connected to the air inlet of the indoor unit (11); the exhaust port of the indoor unit (11) is connected to the air inlet of the secondary supercooling device (123); the exhaust port of the secondary supercooling device (123) is connected to the air inlet of the outdoor heat exchanger (122); the exhaust port of the outdoor heat exchanger (122) is connected to the compressor (121); The outdoor unit (12) further comprises a chassis heat exchanger (124), wherein the chassis heat exchanger (124) is arranged on the chassis of the air conditioner (1), wherein the air inlet of the chassis heat exchanger (124) is connected to the exhaust port of the compressor (121), and the exhaust port is connected to the air inlet of the outdoor heat exchanger (122), and a first valve (125) is arranged between the air inlet of the chassis heat exchanger (124) and the exhaust port of the compressor (121).

2. The air conditioner (1) according to claim 1, characterized in that: An economizer (126), a first refrigerant pipeline (127) and a second refrigerant pipeline (128) are also provided between the exhaust port of the indoor unit (11) and the air inlet of the secondary supercooling device (123); the exhaust port of the indoor unit (11), the economizer (126) and the secondary supercooling device (123) are connected via the first refrigerant pipeline (127); the exhaust port of the indoor unit (11), the economizer (126) and the air intake port of the compressor (121) are connected via the second refrigerant pipeline (128); a first electronic expansion valve (1281) is provided on the second refrigerant pipeline (128); and the first electronic expansion valve (1281) is communicatively connected to the controller of the air conditioner (1).

3. The air conditioner (1) according to claim 2, characterized in that: The outdoor unit (12) further comprises an ambient temperature sensor (129) for obtaining the ambient temperature and a high-pressure pressure sensor (12A) for obtaining the high-pressure pressure of the pipeline; a second electronic expansion valve (12B) is provided at the air inlet of the outdoor heat exchanger (122); the ambient temperature sensor (129), the high-pressure pressure sensor (12A) and the second electronic expansion valve (12B) are all communicatively connected to the controller of the air conditioner (1).

4. The air conditioner (1) according to claim 1, characterized in that: The outdoor unit (12) further comprises a gas-liquid separator (12C), a gas-oil separator (12D) and a four-way valve (12E); the four-way valve (12E) comprises a d port, an e port, a c port and an s port; an air inlet end of the gas-oil separator (12D) is connected to an exhaust port of the compressor (121); an air outlet end is connected to the indoor unit (11) through the d port and the e port of the four-way valve (12E); and an air return end is connected to the compressor (121) through a capillary tube. The exhaust port of the outdoor heat exchanger (122) is connected to the air inlet end of the gas-liquid separator (12C) through the c port and the s port of the four-way valve (12E), and the exhaust end of the gas-liquid separator (12C) is connected to the compressor (121).

5. The air conditioner (1) according to claim 1, characterized in that: The outdoor unit (12) further comprises an air jet enthalpy increase system for supplying air to the compressor (121), the air jet enthalpy increase system being communicatively connected to a controller of the air conditioner (1), and / or the chassis heat exchanger (124) is laid flat on the outdoor heat exchanger (122) side of the chassis.

6. A control method for an air conditioner (1), characterized in that: The air conditioner (1) is the air conditioner (1) as claimed in claim 3, and the control method comprises: Controlling the ambient temperature sensor (129) to obtain the ambient temperature T0; Compare the ambient temperature T0 with the preset ambient temperature; The opening and closing state of the first valve (125) is controlled based on the comparison result.

7. The control method for an air conditioner (1) according to claim 6, characterized in that: The step of "controlling the opening and closing state of the first valve (125) based on the comparison result" further comprises: If T0>T1, the first valve (125) is controlled to be closed; If T0≤T3, the first valve (125) is controlled to be fully open.

8. The control method for an air conditioner (1) according to claim 7, characterized in that: The control method further comprises: Obtaining the operating mode of the air conditioner (1); Controlling the ambient temperature sensor (129) to obtain the ambient temperature T0; Compare the ambient temperature T0 with the preset ambient temperature; Controlling the opening and closing state of the first valve (125) based on the comparison result and the operation mode of the air conditioner (1); If T2<T0≤T1, and the air conditioner (1) is in the defrosting mode, the first valve (125) is controlled to be fully opened and closed after a first preset time delay after the defrosting is completed; If T3<T0≤T2, and the air conditioner (1) is in heating mode, the first valve (125) is controlled to be half open; If T3<T0≤T2, and the air conditioner (1) is in the defrost mode, the first valve (125) is controlled to be fully open.

9. The control method for an air conditioner (1) according to claim 7, characterized in that: The outdoor unit (12) further comprises an air injection enthalpy increase system for supplying air to the compressor (121), the air injection enthalpy increase system being in communication connection with the controller of the air conditioner (1), and the step "if T0≤T3, then controlling the first valve (125) to be fully opened" further comprises: Controlling the high-pressure pressure sensor (12A) to obtain the high-pressure pressure Pd of the pipeline; Comparing the high pressure Pd of the pipeline with the first preset high pressure Pd0; If Pd≤Pd0, the injection enthalpy increase system is controlled to start to supply air to the compressor (121).

10. The control method for an air conditioner (1) according to claim 6, characterized in that: The control method further comprises: Obtaining the operating mode of the air conditioner (1); Controlling the high-pressure pressure sensor (12A) to obtain the high-pressure pressure Pd of the pipeline; Comparing the high pressure Pd of the pipeline with the second preset high pressure Pd1; If Pd≥Pd1, and the air conditioner (1) is in cooling or heating mode, the opening degree of the first valve (125) is controlled to increase.

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