air conditioner

Abstract

The present invention relates to an air conditioner, comprising: a refrigerant circuit, in which the refrigerant circulates in sequence through a compressor, an indoor heat exchanger, a first expansion valve, a flash evaporator, a second expansion valve and an outdoor heat exchanger; an indoor heat exchanger; an outdoor temperature sensor; an inlet water temperature sensor; an exhaust temperature sensor; an outlet water temperature sensor; and a controller, configured to: when the outdoor temperature is lower than a first preset temperature, perform a first logical operation based on the current outdoor temperature and the inlet water temperature to obtain a target intake superheat; adjust the action opening of the second expansion valve to achieve the target intake superheat; perform a second logical operation based on the current frequency of the compressor to obtain a target exhaust superheat; when the exhaust superheat and the target exhaust superheat meet a first condition, after a first preset time period, increase the target intake superheat; when the exhaust superheat and the target exhaust superheat meet a second condition, after a first preset time period, reduce the target intake superheat to ensure a heating effect.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioners, and in particular to an air conditioner. Background Art

[0002] Air conditioners typically include a refrigerant circuit, where the refrigerant circulates through the compressor, condenser, expansion valve, and evaporator. The outdoor unit of the air conditioner is equipped with an outdoor temperature sensor to detect the outdoor temperature, and the water inlet is equipped with an inlet temperature sensor to detect the inlet water temperature.

[0003] In areas with lower outdoor temperatures, a flash evaporator is installed in the refrigerant circuit to ensure indoor heating needs. This evaporator replenishes air to the compressor, thereby improving compressor efficiency. The flash evaporator eliminates liquid on the suction side of the compressor, making it crucial to control the air conditioner's suction superheat.

[0004] In the prior art, the target intake superheat is not adjusted based on the outdoor temperature. Instead, it is fixed, and the refrigerant flow is controlled via the expansion valve to meet the target intake superheat temperature. This results in inaccurate intake superheat control and inaccurate control of the refrigerant status on the compressor intake side. In areas with lower outdoor temperatures, the intake superheat detection results are also affected, and the prior art is unable to correct the intake superheat to meet indoor heating requirements.

[0005] In view of this, this application is filed. Summary of the Invention

[0006] The present invention solves one of the technical problems in the related art at least to a certain extent.

[0007] To this end, the present application aims to provide an air conditioner to facilitate precise heating control of the air conditioner and improve the heating effect.

[0008] To achieve the above object, the present invention provides an air conditioner, comprising:

[0009] A compressor comprising a first air supply port, an air intake port, and an air discharge port;

[0010] The flash evaporator comprises a first refrigerant port, a second refrigerant port and a second air supply port, wherein the first air supply port and the second air supply port are connected;

[0011] The refrigerant circuit is a refrigerant circuit in which the refrigerant is discharged through the exhaust port of the compressor, passes through the indoor heat exchanger and the first expansion valve in sequence, and then flows into the flash evaporator through the first refrigerant port; the refrigerant in the flash evaporator flows out through the second refrigerant port on one side, passes through the second expansion valve and the outdoor heat exchanger, and then flows into the compressor through the air intake port; the refrigerant in the flash evaporator flows out through the second air supply port on the other side, passes through the first air supply port, and then flows into the compressor to circulate;

[0012] The indoor heat exchanger includes a water inlet and a water outlet. The heat exchange medium enters the water inlet to exchange heat with the refrigerant circuit and then flows out through the water outlet.

[0013] An outdoor temperature sensor is provided on the outdoor unit of the air conditioner and is used to detect the outdoor temperature;

[0014] The water inlet temperature sensor is located at the water inlet and is used to detect the water inlet temperature.

[0015] An exhaust temperature sensor is provided at the exhaust port of the compressor and is used to detect the exhaust temperature of the compressor;

[0016] The outlet water temperature sensor is provided at the outlet to detect the outlet water temperature;

[0017] The controller is configured to: when the indoor heat exchanger operates as a condenser, define the difference between the exhaust temperature and the outlet water temperature as the exhaust superheat;

[0018] When the outdoor temperature is lower than a first preset temperature, a first logic operation is performed based on the current outdoor temperature and the inlet water temperature to obtain a target suction superheat; and the opening of the second expansion valve is adjusted to achieve the target suction superheat.

[0019] Performing a second logic operation based on the current compressor frequency to obtain a target exhaust gas superheat;

[0020] When the exhaust gas superheat and the target exhaust gas superheat meet a first condition, after a first preset time period, the target intake air superheat is increased;

[0021] When the exhaust gas superheat and the target exhaust gas superheat satisfy a second condition, the target intake air superheat is reduced after a first preset time period.

[0022] In some embodiments of the present application, the controller is configured to:

[0023] When the outdoor temperature is lower than the second preset temperature and not lower than the first preset temperature, a first logical operation is performed based on the current outdoor temperature and the inlet water temperature to obtain a target intake superheat; and the opening of the second expansion valve is adjusted to achieve the target intake superheat.

[0024] In some embodiments of the present application, the controller is configured to: when the outdoor temperature is not lower than a second preset temperature, set the target intake superheat to a preset superheat value, and adjust the opening of the second expansion valve to reach the preset superheat value.

[0025] In some embodiments of the present application, the controller is configured as follows: a target intake superheat value range is preset in the controller, and when the target intake superheat increases to the maximum value of its value range, the target intake superheat is controlled not to increase any further.

[0026] In some embodiments of the present application, the controller is configured to: when the target intake air superheat decreases to the minimum value of its value range, control the target intake air superheat to not decrease any further.

[0027] In some embodiments of the present application, the controller is configured to: periodically detect the outdoor temperature using an outdoor temperature sensor, and obtain a target suction air superheat within a corresponding period based on the detected outdoor temperature.

[0028] In some embodiments of the present application, further comprising:

[0029] An intake temperature sensor is provided at the intake port of the compressor and is used to detect the intake temperature of the compressor;

[0030] An outdoor coil temperature sensor is provided on the outdoor heat exchanger and is used to detect the coil temperature of the outdoor heat exchanger;

[0031] The difference between the suction temperature and the coil temperature is defined as the suction superheat;

[0032] Define the difference between the suction superheat in the current cycle and the target suction superheat as the suction superheat adjustment value;

[0033] A proportional component is obtained by calculation based on the suction superheat adjustment value;

[0034] Define the difference between the suction superheat adjustment value in the current cycle and the suction superheat adjustment value in the previous cycle as the suction superheat change difference;

[0035] The proportional component is obtained by calculation based on the difference in suction superheat change;

[0036] A third logical operation is performed based on the proportional component and the differential component to obtain the operating opening degree of the second expansion valve.

[0037] In some embodiments of the present application, the controller is configured to obtain a target opening of the second expansion valve based on the sum of the current opening of the second expansion valve and the action opening of the second expansion valve.

[0038] In some embodiments of the present application, the indoor heat exchange is a plate heat exchanger, and the heat exchange medium is water.

[0039] Another aspect of the present invention provides an air conditioner, comprising:

[0040] A compressor comprising a first air supply port, an air intake port, and an air discharge port;

[0041] The flash evaporator comprises a first refrigerant port, a second refrigerant port and a second air supply port, wherein the first air supply port and the second air supply port are connected;

[0042] The refrigerant circuit is a refrigerant circuit in which the refrigerant is discharged through the exhaust port of the compressor, passes through the indoor heat exchanger and the first expansion valve in sequence, and then flows into the flash evaporator through the first refrigerant port; the refrigerant in the flash evaporator flows out through the second refrigerant port on one side, passes through the second expansion valve and the outdoor heat exchanger, and then flows into the compressor through the air intake port; the refrigerant in the flash evaporator flows out through the second air supply port on the other side, passes through the first air supply port, and then flows into the compressor to circulate;

[0043] The indoor heat exchanger includes a water inlet and a water outlet. The heat exchange medium enters the water inlet to exchange heat with the refrigerant circuit and then flows out through the water outlet.

[0044] An outdoor temperature sensor is provided on the outdoor unit of the air conditioner and is used to detect the outdoor temperature;

[0045] The water inlet temperature sensor is located at the water inlet and is used to detect the water inlet temperature.

[0046] An exhaust temperature sensor is provided at the exhaust port of the compressor and is used to detect the exhaust temperature of the compressor;

[0047] The outlet water temperature sensor is provided at the outlet to detect the outlet water temperature;

[0048] The controller is configured to: when the indoor heat exchanger operates as a condenser, define the difference between the exhaust temperature and the outlet water temperature as the exhaust superheat;

[0049] When the outdoor temperature is lower than a first preset temperature, a first logic operation is performed based on the current outdoor temperature and the inlet water temperature to obtain a target suction superheat; and the opening of the second expansion valve is adjusted to achieve the target suction superheat.

[0050] Performing a second logic operation based on the current compressor frequency to obtain a target exhaust gas superheat;

[0051] When the difference between the exhaust gas superheat and the target exhaust gas superheat satisfies a third condition, the target intake superheat is increased after a first preset time period.

[0052] When the difference between the exhaust gas superheat and the target exhaust gas superheat satisfies a fourth condition, the target intake air superheat is lowered after a first preset time period.

[0053] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 is a schematic diagram of the system structure of an air conditioner according to one embodiment of the present application;

[0055] Figure 2is a schematic diagram of a refrigerant circulation in a heating mode of an air conditioner according to one embodiment of the present application;

[0056] Figure 3 is a schematic diagram of a refrigerant circulation in a cooling mode of an air conditioner according to one embodiment of the present application;

[0057] Figure 4 This is a first control process for regulating the suction superheat of an air conditioner according to one embodiment of the present application;

[0058] Figure 5 This is a second control process for regulating the suction superheat of an air conditioner according to one embodiment of the present application;

[0059] Figure 6 This is a third control process for regulating the suction superheat of an air conditioner according to one embodiment of the present application;

[0060] Figure 7 This is a general flow chart for regulating and controlling the suction superheat of an air conditioner according to one embodiment of the present application;

[0061] Figure 8 This is a control process for adjusting the suction air superheat of an air conditioner according to another embodiment of the present application;

[0062] Figure 9 This is a general flow chart for regulating and controlling the suction superheat of an air conditioner according to another embodiment of the present application;

[0063] Figure 10 This is a flow chart of the opening control of the second expansion valve of the air conditioner according to one embodiment of the present application;

[0064] Figure 11 This is a hardware configuration block diagram according to one embodiment of the present application.

[0065] In the above figures: compressor 1; first air supply port 11; air intake port 12; exhaust port 13; exhaust temperature sensor 2; four-way valve 3; indoor heat exchanger 4; water inlet 41; water outlet 42; first expansion valve 5; flash evaporator 6; first refrigerant port 61; second refrigerant port 62; second air supply port 63; second expansion valve 7; controller 71; bus 81; memory 82; processor 83; communication interface 84; outdoor heat exchanger 9; outdoor coil temperature sensor 10. DETAILED DESCRIPTION

[0066] The present invention is described in detail below by way of exemplary embodiments, but it should be understood that elements, structures, and features of one embodiment may be beneficially combined in other embodiments without further description.

[0067] In the following, reference will be made to the Figures 1-11 The embodiments of the present application are described in detail.

[0068] In this application, the air conditioner includes an indoor air conditioner and an outdoor air conditioner. When the air conditioner operates in cooling mode, the air conditioner performs a refrigeration cycle of the indoor air conditioner by using a compressor 1, an outdoor heat exchanger 9, a first expansion valve 5, a flash evaporator 6, a second expansion valve 7, and an indoor heat exchanger 4.

[0069] The refrigeration cycle includes a series of processes involving compression, condensation, expansion and evaporation, and supplies refrigerant to the heat exchange medium that has been conditioned and heat exchanged. The refrigerant absorbs heat to provide cooling to the heat exchange medium, thereby achieving temperature regulation of the indoor heat exchange medium.

[0070] Compressor 1 compresses low-temperature, low-pressure refrigerant gas and discharges high-temperature, high-pressure refrigerant gas, which flows into outdoor heat exchanger 9. Outdoor heat exchanger 9 condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

[0071] The first expansion valve 5 or the second expansion valve 7 expands the high-temperature and high-pressure liquid-phase refrigerant condensed in the outdoor heat exchanger 9 into a low-pressure liquid-phase refrigerant.

[0072] The flash evaporator 6 is used to separate the low-pressure liquid refrigerant into the gaseous refrigerant to replenish the compressor 1.

[0073] The indoor heat exchanger 4 evaporates the expanded refrigerant and returns the low-temperature and low-pressure refrigerant gas to the compressor 1. The indoor heat exchanger 4 can achieve a cooling effect by utilizing the latent heat of evaporation of the refrigerant to exchange heat with the indoor heat exchange medium.

[0074] During the entire refrigeration cycle, the air conditioner indoor unit can regulate the temperature of the indoor heat exchange medium.

[0075] When the air conditioner operates in heating mode, the air conditioner performs a heating cycle of the indoor unit of the air conditioner through the compressor 1 , the outdoor heat exchanger 9 , the expansion valve and the indoor heat exchanger 4 .

[0076] The heating cycle includes a series of processes involving compression, condensation, expansion and evaporation, and supplies refrigerant to the heat exchange medium that has been conditioned and heat exchanged. The refrigerant provides heat to the heat exchange medium through the heat release process, thereby achieving temperature regulation of the indoor heat exchange medium.

[0077] During the heating cycle, compressor 1 compresses low-temperature, low-pressure refrigerant gas and discharges it into high-temperature, high-pressure refrigerant gas, which then flows into indoor heat exchanger 4. Indoor heat exchanger 4 condenses the compressed refrigerant into a liquid phase, and the heat generated by the condensation is exchanged with the indoor air flowing through indoor heat exchanger 4, thereby raising the temperature of the heat exchange medium.

[0078] The first expansion valve 5 or the second expansion valve 7 expands the high-temperature and high-pressure liquid-phase refrigerant condensed in the outdoor heat exchanger 9 into a low-pressure liquid-phase refrigerant.

[0079] The flash evaporator 6 is used to separate the low-pressure liquid refrigerant into the gaseous refrigerant to replenish the compressor 1.

[0080] The outdoor heat exchanger 9 evaporates the expanded refrigerant and returns the refrigerant gas at low temperature and low pressure to the compressor 1. The outdoor heat exchanger 9 can achieve temperature regulation of the indoor heat exchange medium by utilizing the condensation heat release of the refrigerant to exchange heat with the heat exchange medium.

[0081] During the entire heating cycle, the air conditioner indoor unit can adjust the temperature of the indoor heat exchange medium.

[0082] The indoor heat exchanger 4 and the outdoor heat exchanger 9 function as a condenser or an evaporator. When the indoor heat exchanger 4 functions as a condenser, the air conditioner indoor unit functions as a heater in heating mode, and when the indoor heat exchanger 4 functions as an evaporator, the air conditioner indoor unit functions as a cooler in cooling mode.

[0083] As attached Figures 1-11 As shown, in one embodiment of the air conditioner of the present invention.

[0084] The air conditioner includes a compressor 1, a flash evaporator 6, an indoor heat exchanger 4, an outdoor heat exchanger 9, a first expansion valve 5, a second expansion valve 7, a four-way valve 3 and a refrigerant circuit.

[0085] Both the indoor heat exchanger 4 and the outdoor heat exchanger 9 are connected to the compressor 1 via the four-way valve 3. The first expansion valve 5 and the second expansion valve 7 are electronic expansion valves. In heating mode, the second expansion valve 7 can expand the liquid refrigerant that has undergone the condensation process into a low-pressure liquid refrigerant. In cooling mode, the first expansion valve 5 can expand the liquid refrigerant that has undergone the condensation process into a low-pressure liquid refrigerant.

[0086] The compressor 1 includes a first air supply port 11, an air intake port 12 and an air exhaust port 13. The refrigerant that absorbs heat and undergoes an evaporation process enters the compressor 1 from the air intake port 12. The compressor 1 compresses the gaseous refrigerant into a high-temperature and high-pressure state and then discharges it from the exhaust port 13. The first air supply port 11 is connected to the flash evaporator 6, and the flash evaporator 6 is used to supply air to the compressor 1 to reduce the enthalpy value, thereby ensuring the heating efficiency of the compressor 1.

[0087] The indoor heat exchanger 4 and the outdoor heat exchanger 9 are respectively connected to the compressor 1 via a four-way valve 3 in the refrigerant circuit. The four-way valve 3 includes a first valve port, a second valve port, a third valve port, and a fourth valve port. The intake port 12 of the compressor 1 is fixedly connected to the first valve port, the exhaust port 13 of the compressor 1 is fixedly connected to the third valve port, the second valve port is connected to the indoor heat exchanger 4, and the fourth valve port is connected to the outdoor heat exchanger 9.

[0088] When the air conditioner is in cooling mode, the first valve port is connected to the second valve port, and the third valve port is connected to the fourth valve port. When the air conditioner is in heating mode, the first valve port is connected to the fourth valve port, and the second valve port is connected to the third valve port.

[0089] The flash evaporator 6 includes a first refrigerant port 61 , a second refrigerant port 62 and a second air supply port 63 . The first air supply port 11 of the compressor 1 is connected to the second refrigerant port 62 of the flash evaporator 6 .

[0090] In the refrigerant circuit of the heating cycle, the refrigerant is discharged through the exhaust port 13 of the compressor 1, passes through the indoor heat exchanger 4, the first expansion valve 5, and then flows into the flash evaporator 6 through the first refrigerant port 61. The refrigerant in the flash evaporator 6 flows out through the second refrigerant port 62, passes through the second expansion valve 7 and the outdoor heat exchanger 9, and then flows into the compressor 1 through the air intake port 12. The refrigerant in the flash evaporator 6 also flows out through the second air supply port 63, passes through the first air supply port 11, and flows into the compressor 1 to circulate. In the heating cycle, the indoor heat exchanger 4 acts as a condenser, and the outdoor heat exchanger 9 acts as an evaporator.

[0091] The indoor heat exchanger 4 can be a plate-type heat exchanger and includes a water inlet 41 and a water outlet 42. A heat exchange medium enters through the water inlet 41 to exchange heat with the refrigerant circuit, and after heat exchange, the heat exchange medium flows out through the water outlet 42. The heat exchange medium can be water, and after heat exchange with the refrigerant, the water temperature rises, providing domestic hot water for users.

[0092] The air conditioner also includes a controller 71 to control the operation of various components within the air conditioner, enabling them to function and achieve their intended functions. Controller 71 is a device that generates operational control signals based on command opcodes and timing signals, instructing the air conditioner to execute control commands. For example, in response to a power-on or power-off command issued by a user, controller 71 can execute operations related to the object selected in the power-on or power-off command.

[0093] The air conditioner is also provided with a control device, which is illustratively a remote controller that communicates with the controller 71 using infrared or other communication methods. The remote controller allows the user to control the air conditioner in various ways, thereby enabling interaction between the user and the air conditioner.

[0094] The embodiment of the present application further provides a hardware structure diagram of a controller 71, which includes a processor 83 and, optionally, a memory 82 and a communication interface 84 connected to the processor 83. The processor 83, the memory 82, and the communication interface 84 are connected via a bus 81.

[0095] The processor 83 can be a central processing unit 83 (CPU), a general-purpose processor 83, a network processor 83 (NP), a digital signal processor 83 (DSP), a microprocessor 83, a microcontroller 718, a programmable logic device (PLD), or any combination thereof. The processor 83 can also be any other device with processing functionality, such as a circuit, a device, or a software module. The processor 83 can also include multiple CPUs, and the processor 83 can be a single-core (single-CPU) processor 83 or a multi-core (multi-CPU) processor 83. The processor 83 here can refer to one or more devices, circuits, or processing cores for processing data (such as computer program instructions).

[0096] The memory 82 can be a read-only memory 82 (ROM) or other types of static storage devices that can store static information and instructions, a random access memory 82 (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory 82 (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer. The embodiment of the present application does not impose any restrictions on this. The memory 82 can exist independently or be integrated with the processor 83. Among them, the memory 82 can contain computer program code. The processor 83 is used to execute the computer program code stored in the memory 82, thereby realizing the control method of the air conditioner provided in the embodiment of the present application.

[0097] The communication interface 84 can be used to communicate with other devices or communication networks (such as Ethernet, radio access network (RAN), wireless local area network (WLAN), etc.). The communication interface 84 can be a module, a circuit, a transceiver or any device that can achieve communication.

[0098] The bus 81 may be a peripheral component interconnect (PCI) bus 81 or an extended industry standard architecture (EISA) bus 81. The bus 81 may be divided into an address bus 81, a data bus 81, a control bus 81, etc. Figure 11 Only one thick line is used in the figure, but it does not mean that there is only one bus 81 or only one type of bus 81.

[0099] In some embodiments, the air conditioner further includes an outdoor temperature sensor, a water inlet temperature sensor, an exhaust temperature sensor 2 , a water outlet temperature sensor, an air intake temperature sensor and an outdoor coil temperature sensor 10 .

[0100] The outdoor temperature sensor is provided in the outdoor unit of the air conditioner and is used to detect the outdoor temperature. The outdoor temperature sensor is electrically connected to the controller 71 , and detects the outdoor temperature and sends the outdoor temperature to the controller 71 in the form of an electrical signal.

[0101] The inlet water temperature sensor is located at the water inlet 41 of the indoor heat exchanger 4 and is used to detect the inlet water temperature. The inlet water temperature sensor is electrically connected to the controller 71. The inlet water temperature sensor detects the inlet water temperature of the heat exchange medium and transmits the inlet water temperature to the controller 71 in the form of an electrical signal.

[0102] The exhaust temperature sensor 2 is provided at the exhaust port 13 of the compressor 1 and is used to detect the exhaust temperature of the compressor 1. The exhaust temperature sensor 2 is electrically connected to the controller 71. The exhaust temperature sensor 2 detects the exhaust temperature of the heat exchange medium and sends the exhaust temperature to the controller 71 in the form of an electrical signal.

[0103] The outlet water temperature sensor is located at the outlet 42 of the indoor heat exchanger 4 and is used to detect the outlet water temperature. The outlet water temperature sensor is electrically connected to the controller 71 and detects the outlet water temperature of the heat exchange medium and transmits the outlet water temperature to the controller 71 in the form of an electrical signal.

[0104] The intake air temperature sensor is located at the intake port 12 of the compressor 1 and is used to detect the intake air temperature of the compressor 1. The intake air temperature sensor is electrically connected to the controller 71. The intake air temperature sensor detects the intake air temperature of the compressor 1 and sends the intake air temperature to the controller 71 in the form of an electrical signal.

[0105] The outdoor coil temperature sensor 10 is located at the middle coil of the outdoor heat exchanger 9 and is used to detect the coil temperature of the outdoor heat exchanger 9. The outdoor coil temperature sensor 10 is electrically connected to the controller 71. The outdoor coil temperature sensor 10 detects the coil temperature of the outdoor heat exchanger 9 and transmits the coil temperature of the outdoor heat exchanger 9 to the controller 71 in the form of an electrical signal.

[0106] The controller 71 is configured to define the difference between the exhaust gas temperature and the outlet water temperature as the exhaust gas superheat when the indoor heat exchanger 4 operates as a condenser.

[0107] When the outdoor temperature is lower than the first preset temperature, a first logical operation is performed based on the current outdoor temperature and the inlet water temperature to obtain a target intake superheat, and the controller 71 controls the opening of the second expansion valve 7 to achieve the target intake superheat.

[0108] A second logical operation is performed based on the current frequency of the compressor 1 to obtain a target exhaust gas superheat.

[0109] When the exhaust superheat and the target exhaust superheat meet a first condition, the target intake superheat is increased after a first preset time period. When the exhaust superheat and the target exhaust superheat meet a second condition, the target intake superheat is decreased after a first preset time period.

[0110] In this application, when the outdoor temperature sensor detects that the outdoor temperature is lower than the first preset temperature, it indicates that the outdoor temperature is low. At low outdoor temperatures, the outdoor coil temperature detected by the outdoor coil temperature sensor 10 may deviate significantly, thereby affecting the accuracy of suction superheat detection. Therefore, controlling the opening of the second expansion valve 7 solely based on suction superheat detection may result in significant deviations in the actual suction superheat value.

[0111] When the outdoor temperature is high, the indoor temperature is high in heating mode. This application uses the more accurate exhaust superheat data to correct the target intake superheat value when the outdoor temperature is low, thereby achieving more accurate intake superheat control. Optionally, the first preset temperature can be set to -15°C.

[0112] In some embodiments, when the outdoor temperature is lower than a second preset temperature but not lower than the first preset temperature, a first logical operation is performed based on the current outdoor temperature and the inlet water temperature to obtain a target intake superheat. The opening of the second expansion valve 7 is adjusted to achieve the target intake superheat. The second preset temperature can be set to 3°C, and the first preset temperature can be set to -15°C.

[0113] At this time, through the first logical operation, the action opening of the second electronic expansion valve is continuously adjusted, so that the current exhaust superheat is continuously close to the target exhaust superheat, thereby improving the control accuracy of the suction superheat, ensuring that there is no liquid on the suction side of the compressor 1, and improving the protection for the low-temperature heating operation of the compressor 1.

[0114] In some embodiments, when the outdoor temperature is not lower than a second preset temperature, the target intake superheat is set to a preset superheat value, and the opening of the second expansion valve 7 is adjusted to achieve the preset superheat value. Optionally, the second preset temperature may be set to 3°C, the preset superheat value may be a fixed value, and the preset superheat value may be set to 0.

[0115] In some embodiments, the first logical operation is: target intake superheat = (Toutdoor + K1) * K2 + (K3 - Twaterin) * K4 + K5. Where Toutdoor is the outdoor temperature, Twaterin is the inlet water temperature, and K1, K2, K3, K4, and K5 are constants. For example, K1 = 12; K2 = 0.05; K3 = 36; K4 = 0.08; and K5 = 1.

[0116] When calculating the target intake superheat, the present application only uses the detected outdoor temperature and water inlet temperature to calculate the target intake superheat. Fewer parameter values ​​are required for calculation, and it is easier to measure. The accumulation of deviations in the calculation of multiple parameter values ​​can be reduced, and the calculation accuracy of the obtained target intake superheat can be improved. The target intake superheat obtained by controlling and adjusting the second expansion valve 7 by the controller 71 is more accurate, thereby improving the heating efficiency of the air conditioner during low-temperature heating.

[0117] In some embodiments, the second logical operation is: target exhaust superheat = A*compressor 1 frequency + B, wherein A and B are constants, which can be set to A=0.24 and B=20.

[0118] The first condition is: exhaust superheat ≤ target exhaust superheat - E, where E is a constant and can be set to E=5.

[0119] That is, when the exhaust superheat is less than or equal to the target exhaust superheat - E, the exhaust superheat is low and the target exhaust superheat is high. While adjusting the exhaust superheat to the target exhaust superheat, the target intake superheat is corrected. After the first preset time period, the target intake superheat is increased.

[0120] It can be set that after every first preset time period, the target suction superheat degree=current target suction superheat degree+F, wherein F is a constant and F can be set to 1. The first preset time period can be set to 5 minutes.

[0121] In some embodiments, the controller 71 is pre-set with a target intake superheat value range. When the target intake superheat value increases to a maximum value within the value range, the target intake superheat value is controlled to stop increasing. The maximum value within the value range of the target intake superheat value can be set to 0.

[0122] In some embodiments, when the difference between the exhaust gas superheat and the target exhaust gas superheat satisfies a third condition, the target intake air superheat is increased after a first preset time period.

[0123] The third condition is: exhaust superheat - target exhaust superheat ≤ -E, where E is a constant and can be set to E=5.

[0124] That is, when exhaust superheat - target exhaust superheat ≤ -E, the exhaust superheat is low and the target exhaust superheat is high. When adjusting the exhaust superheat to the target exhaust superheat, the target intake superheat is corrected. After the first preset time period, the target intake superheat is increased.

[0125] It can be set that after every first preset time period, the target suction superheat degree=current target suction superheat degree+F, wherein F is a constant and F can be set to 1. The first preset time period can be set to 5 minutes.

[0126] In some embodiments, the controller 71 is pre-set with a target intake superheat value range. When the target intake superheat value increases to a maximum value within the value range, the target intake superheat value is controlled to stop increasing. The maximum value within the value range of the target intake superheat value can be set to 0.

[0127] In some embodiments, the second condition is: exhaust superheat ≥ target exhaust superheat + C, where C is a constant, which can be set to C=4.

[0128] That is, when the exhaust superheat ≥ the target exhaust superheat + C, the exhaust superheat is high and the target exhaust superheat is low. While adjusting the exhaust superheat to the target exhaust superheat, the target intake superheat is corrected. After the first preset time period, the target intake superheat is lowered.

[0129] It can be set that after every first preset time period, the target suction superheat degree=current target suction superheat degree-D, wherein D is a constant and D can be set to 1. The first preset time period can be set to 5 minutes.

[0130] In some embodiments, the controller 71 is preset with a target intake superheat value range. When the target intake superheat value decreases to the minimum value of the value range, the target intake superheat value is controlled to not decrease any further. The minimum value of the target intake superheat value range can be set to -2.

[0131] In some embodiments, when the difference between the exhaust gas superheat and the target exhaust gas superheat satisfies a fourth condition, the target intake air superheat is reduced after a first preset time period.

[0132] The fourth condition is: exhaust gas superheat - target exhaust gas superheat ≥ C, where C is a constant and may be set to C=4.

[0133] That is, when exhaust superheat - target exhaust superheat ≥ C, the exhaust superheat is high and the target exhaust superheat is low. When adjusting the exhaust superheat to the target exhaust superheat, the target intake superheat is corrected. After the first preset time period, the target intake superheat is lowered.

[0134] It can be set that after every first preset time period, the target suction superheat degree=current target suction superheat degree-D, wherein D is a constant and D can be set to 1. The first preset time period can be set to 5 minutes.

[0135] In some embodiments, the controller 71 is preset with a target intake superheat value range. When the target intake superheat value decreases to the minimum value of the value range, the target intake superheat value is controlled to not decrease any further. The minimum value of the target intake superheat value range can be set to -2.

[0136] In some embodiments, an outdoor temperature sensor periodically detects the outdoor temperature, and a target intake superheat for each period is determined based on the detected outdoor temperature. The target intake superheat is used to control the opening of the second expansion valve 7, thereby periodically adjusting the current intake superheat to the target intake superheat. This allows for precise control of the target intake superheat, improves the heating performance of the compressor 1, and prevents the intake side of the compressor 1 from drawing in liquid refrigerant.

[0137] In some embodiments, the difference between the suction air temperature and the coil temperature is defined as the suction air superheat, and the difference between the suction air superheat in the current cycle and the target suction air superheat is defined as the suction air superheat adjustment value.

[0138] The method for controlling the actuation degree of the second expansion valve 7 using the target intake superheat is as follows: a proportional component is calculated based on the intake superheat adjustment value. The difference between the intake superheat adjustment value in the current cycle and the intake superheat adjustment value in the previous cycle is defined as the intake superheat change difference. A differential component is calculated based on the intake superheat change difference. A third logical operation is performed on the proportional component and the differential component to determine the desired actuation degree of the second expansion valve 7.

[0139] In the step of calculating and obtaining the proportional component based on the intake air superheat adjustment value, the proportional component = the intake air superheat adjustment value * P, where P is a constant.

[0140] In the step of calculating the differential component based on the suction air superheat variation difference, the differential component=the suction air superheat variation difference*D, where D is a constant.

[0141] In some embodiments, the third logical operation includes: performing an operation through a proportional component, a differential component, and a constant Gain to obtain a desired action opening degree of the second expansion valve 7 .

[0142] The third logic is: (proportional component+differential component) / constant Gain=required opening degree of the second expansion valve 7 .

[0143] The target opening degree of the second expansion valve 7 is obtained by summing the current actuation opening degree of the second expansion valve 7 and the required actuation opening degree of the second expansion valve 7 .

[0144] When the required action opening of the second expansion valve 7 is a positive number, the controller 71 controls the second expansion valve 7 to increase its action opening to reach the target opening of the second expansion valve 7, thereby achieving precise control of the suction superheat by controlling the second expansion valve 7.

[0145] When the required action opening of the second expansion valve 7 is a negative number, the controller 71 controls the second expansion valve 7 to reduce its action opening to reach the target opening of the second expansion valve 7, thereby achieving precise control of the suction superheat by controlling the second expansion valve 7.

[0146] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0147] In the present invention, unless otherwise expressly specified or limited, the terms "installed," "connected," "connect," "fixed," and the like should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections, electrical connections, or communication between them; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components, unless otherwise expressly limited. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0148] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

[0149] In the present invention, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Therefore, a feature specified as "first," "second," "third," and "fourth" may explicitly or implicitly include one or more of the features.

[0150] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is at a higher level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0151] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0152] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. An air conditioner, characterized in that: include: A compressor comprising a first air supply port, an air intake port, and an air discharge port; The flash evaporator comprises a first refrigerant port, a second refrigerant port and a second air supply port, wherein the first air supply port and the second air supply port are connected; A refrigerant circuit, in which the refrigerant is discharged through the exhaust port of the compressor, passes through the indoor heat exchanger and the first expansion valve in sequence, and then flows into the flash evaporator through the first refrigerant port; the refrigerant in the flash evaporator flows out through the second refrigerant port on one route, passes through the second expansion valve and the outdoor heat exchanger, and then flows into the compressor through the air intake port; the refrigerant in the flash evaporator flows out through the second air supply port on another route, passes through the first air supply port, and flows into the compressor for circulation; The indoor heat exchanger includes a water inlet and a water outlet. The heat exchange medium enters through the water inlet to exchange heat with the refrigerant circuit and then flows out through the water outlet. An outdoor temperature sensor is provided on the outdoor unit of the air conditioner and is used to detect the outdoor temperature; an inlet water temperature sensor, which is arranged at the water inlet and is used to detect the inlet water temperature; an exhaust temperature sensor, which is provided at the exhaust port of the compressor and is used to detect the exhaust temperature of the compressor; An outlet water temperature sensor is provided at the water outlet and is used to detect the outlet water temperature; an intake air temperature sensor, which is arranged at the intake port of the compressor and is used to detect the intake air temperature of the compressor; an outdoor coil temperature sensor, which is provided on the outdoor heat exchanger and is used to detect the coil temperature of the outdoor heat exchanger; The difference between the suction temperature and the coil temperature is defined as suction superheat; The controller is configured to: when the indoor heat exchanger operates as a condenser, define the difference between the exhaust temperature and the outlet water temperature as the exhaust superheat; When the outdoor temperature is lower than a first preset temperature, a first logical operation is performed based on the current outdoor temperature and the inlet water temperature to obtain a target intake superheat; the opening of the second expansion valve is adjusted to achieve the target intake superheat; wherein the first logical operation is: target intake superheat = (Toutdoor + K1) * K2 + (K3 - Twaterin) * K4 + K5; wherein Toutdoor is the outdoor temperature, Twaterin is the inlet water temperature, and K1, K2, K3, K4, and K5 are constants; A second logical operation is performed based on the current frequency of the compressor to obtain a target exhaust gas superheat; wherein the second logical operation is: target exhaust gas superheat = A*compressor frequency + B, where A and B are constants; When the exhaust superheat and the target exhaust superheat meet a first condition, after a first preset time period, the target intake superheat is increased; wherein the first condition is: exhaust superheat ≤ target exhaust superheat - E, where E is a constant; When the exhaust superheat and the target exhaust superheat meet a second condition, the target intake superheat is reduced after a first preset time period; the second condition is: exhaust superheat ≥ target exhaust superheat + C, where C is a constant.

2. The air conditioner according to claim 1, characterized in that The controller is configured as: When the outdoor temperature is lower than a second preset temperature and not lower than the first preset temperature, a first logical operation is performed based on the current outdoor temperature and the inlet water temperature to obtain a target intake superheat; and the opening degree of the second expansion valve is adjusted to achieve the target intake superheat.

3. The air conditioner according to claim 1, characterized in that The controller is configured to: when the outdoor temperature is not lower than a second preset temperature, set the target intake superheat to a preset superheat value, and adjust the opening of the second expansion valve to achieve the preset superheat value.

4. The air conditioner according to claim 1, wherein: The controller is configured to: a value range of the target intake air superheat is preset in the controller, and when the target intake air superheat increases to a maximum value of the value range, the target intake air superheat is controlled not to increase any further.

5. The air conditioner according to claim 4, characterized in that The controller is configured to: when the target intake air superheat degree decreases to a minimum value within its value range, control the target intake air superheat degree to no longer decrease.

6. The air conditioner according to claim 1, characterized in that The controller is configured to: the outdoor temperature sensor periodically detects the outdoor temperature, and obtain a target suction air superheat in a corresponding period based on the detected outdoor temperature.

7. The air conditioner according to claim 6, characterized in that Also includes: defining the difference between the suction superheat in the current cycle and the target suction superheat as the suction superheat adjustment value; Obtaining a proportional component by calculation based on the suction superheat adjustment value; Define the difference between the suction superheat adjustment value in the current cycle and the suction superheat adjustment value in the previous cycle as the suction superheat change difference; Obtaining a differential component by calculation based on the suction air superheat change difference; A third logical operation is performed based on the proportional component and the differential component to obtain a required opening degree of the second expansion valve.

8. The air conditioner according to claim 7, characterized in that The controller is configured to obtain a target opening degree of the second expansion valve based on a sum of a current actuation opening degree of the second expansion valve and a required actuation opening degree of the second expansion valve.

9. The air conditioner according to claim 1, wherein: The indoor heat exchange is a plate heat exchanger, and the heat exchange medium is water.

10. An air conditioner, characterized in that: include: A compressor comprising a first air supply port, an air intake port, and an air discharge port; The flash evaporator comprises a first refrigerant port, a second refrigerant port and a second air supply port, wherein the first air supply port and the second air supply port are connected; A refrigerant circuit, in which the refrigerant is discharged through the exhaust port of the compressor, passes through the indoor heat exchanger and the first expansion valve in sequence, and then flows into the flash evaporator through the first refrigerant port; the refrigerant in the flash evaporator flows out through the second refrigerant port on one route, passes through the second expansion valve and the outdoor heat exchanger, and then flows into the compressor through the air intake port; the refrigerant in the flash evaporator flows out through the second air supply port on another route, passes through the first air supply port, and flows into the compressor for circulation; The indoor heat exchanger includes a water inlet and a water outlet. The heat exchange medium enters through the water inlet to exchange heat with the refrigerant circuit and then flows out through the water outlet. An outdoor temperature sensor is provided on the outdoor unit of the air conditioner and is used to detect the outdoor temperature; an inlet water temperature sensor, which is arranged at the water inlet and is used to detect the inlet water temperature; an exhaust temperature sensor, which is provided at the exhaust port of the compressor and is used to detect the exhaust temperature of the compressor; An outlet water temperature sensor is provided at the water outlet and is used to detect the outlet water temperature; an intake air temperature sensor, which is arranged at the intake port of the compressor and is used to detect the intake air temperature of the compressor; an outdoor coil temperature sensor, which is provided on the outdoor heat exchanger and is used to detect the coil temperature of the outdoor heat exchanger; The difference between the suction temperature and the coil temperature is defined as suction superheat; The controller is configured to: when the indoor heat exchanger operates as a condenser, define the difference between the exhaust temperature and the outlet water temperature as the exhaust superheat; When the outdoor temperature is lower than a first preset temperature, a first logical operation is performed based on the current outdoor temperature and the inlet water temperature to obtain a target intake superheat; the opening of the second expansion valve is adjusted to achieve the target intake superheat; wherein the first logical operation is: target intake superheat = (Toutdoor + K1) * K2 + (K3 - Twaterin) * K4 + K5; wherein Toutdoor is the outdoor temperature, Twaterin is the inlet water temperature, and K1, K2, K3, K4, and K5 are constants; A second logical operation is performed based on the current frequency of the compressor to obtain a target exhaust gas superheat; wherein the second logical operation is: target exhaust gas superheat = A*compressor frequency + B, where A and B are constants; When the difference between the exhaust superheat and the target exhaust superheat satisfies a third condition, the target intake superheat is increased after a first preset time period. The third condition is: exhaust superheat - target exhaust superheat ≤ -E, where E is a constant. When the difference between the exhaust superheat and the target exhaust superheat satisfies a fourth condition, the target intake superheat is reduced after a first preset time period; wherein the fourth condition is: exhaust superheat - target exhaust superheat ≥ C, wherein C is a constant.

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