KR20210096481A - Air conditioner - Google Patents

Abstract

The present invention relates to an air conditioner. The air conditioner according to an embodiment of the present invention includes a compressor for compressing and discharging a refrigerant, an accumulator for recovering a liquid refrigerant contained in the refrigerant flowing into the compressor, and an ejector for discharging a mixed refrigerant by mixing the refrigerant discharged from the compressor and the liquid refrigerant recovered by the accumulator, wherein the mixed refrigerant discharged from the ejector can be injected into the compressor. In addition, various embodiments are possible. The air conditioner of the present invention can improve the efficiency of a heating operation through a gas refrigerant injection cycle using the liquid refrigerant recovered by the accumulator.

Description

Air conditioner {AIR CONDITIONER}

The present invention relates to an air conditioner, and more particularly, to an air conditioner using a gas phase refrigerant injection cycle.

The air conditioner is installed to provide a more comfortable indoor environment to humans by discharging cold and hot air into the room to adjust the indoor temperature and purify the indoor air in order to create a comfortable indoor environment. In general, an air conditioner includes an indoor unit configured as a heat exchanger and installed indoors, and an outdoor unit configured as a compressor and a heat exchanger and supplying a refrigerant to the indoor unit.

The air conditioner is operated for cooling or heating according to the flow of refrigerant. During cooling operation, high-temperature and high-pressure liquid refrigerant is supplied to the indoor unit from the outdoor unit's compressor through the outdoor unit's heat exchanger, and as the refrigerant expands and vaporizes in the indoor unit's heat exchanger, the ambient air temperature decreases, Accordingly, the cold air is discharged into the room. During heating operation, high-temperature and high-pressure gaseous refrigerant is supplied from the compressor of the outdoor unit to the indoor unit, and air heated by the energy released as the high-temperature and high-pressure gaseous refrigerant is liquefied in the heat exchanger of the indoor unit is released into the indoor unit according to the operation of the indoor unit fan. is discharged with

On the other hand, an air conditioner introduces a vapor injection cycle in which a gaseous refrigerant (hereinafter, gaseous refrigerant) is injected and injected into a compressor that compresses the refrigerant in order to improve cooling or heating capacity. .

In the case of the conventional gas phase refrigerant injection cycle, the pipe between the indoor heat exchanger and the outdoor heat exchanger is branched and connected to the injection unit provided in the compressor, and the branched pipe includes an expansion valve for expanding the refrigerant and a heat exchanger for exchanging the expanded refrigerant. A supercooling heat exchanger (hereinafter, a supercooler) is further provided. This structure is to allow the branched refrigerant to expand under reduced pressure and then heat exchange to inject and inject the superheated gaseous refrigerant into the compressor.

This gas phase refrigerant injection cycle can increase the amount of circulated refrigerant by overcoming the limitation of refrigerant suction limited by the density of the refrigerant sucked into the compressor and the volume of the compression chamber, thereby improving the compression capacity of the compressor, The performance of cooling operation or heating operation is improved.

However, in the case of the conventional gas phase refrigerant injection cycle, if the superheat of the injected refrigerant is high, it may cause overheating and reduced efficiency of the compressor. There was a problem of overloading the compressor and causing damage. In addition, since a configuration such as a supercooler or a flash tank must be provided to prevent liquid refrigerant from flowing into the compressor in the gas phase refrigerant injection cycle, there is a problem in that the production cost is increased.

An object of the present invention is to provide an air conditioner capable of improving operating efficiency during heating operation through a gas phase refrigerant injection cycle using liquid refrigerant recovered from an accumulator.

In order to achieve the above object, an air conditioner according to various embodiments of the present invention includes a compressor for compressing and discharging a refrigerant, an accumulator for recovering liquid refrigerant contained in the refrigerant flowing into the compressor, and a refrigerant discharged from the compressor and the accumulator. It includes an ejector that mixes the recovered liquid refrigerant and discharges the mixed refrigerant, and the mixed refrigerant discharged from the ejector may be injected into the compressor.

According to various embodiments of the present invention, through the gas phase refrigerant injection cycle using the liquid refrigerant recovered from the accumulator, the flow rate of the refrigerant to the condenser and the evaporator can be increased and the discharge temperature of the compressor can be lowered, so that during heating operation It can improve the operation efficiency and expand the operation range.

In addition, according to various embodiments of the present invention, a gas phase refrigerant injection cycle can be configured without a configuration such as a supercooler or a flash tank, thereby improving price competitiveness.

Further scope of applicability of the present invention will become apparent from the following detailed description. However, it should be understood that the detailed description and specific embodiments such as preferred embodiments of the present invention are given by way of illustration only, since various changes and modifications within the spirit and scope of the present invention may be clearly understood by those skilled in the art.

1 is a diagram illustrating the configuration of an air conditioner according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of an outdoor unit and an indoor unit of FIG. 1 .
3 is a diagram schematically illustrating an internal structure of an ejector.
4 is a block diagram of an air conditioner according to an embodiment of the present invention.
5A and 5B are flowcharts illustrating a method of operating an air conditioner according to an embodiment of the present invention.
6 is a view showing a PH diagram showing the state of the refrigerant of the air conditioner using the gas phase refrigerant injection cycle, according to an embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

Spatially relative terms "below", "beneath", "lower", "above", "upper", etc. It can be used to easily describe the correlation between a component of , and another component. Spatially relative terms should be understood as terms including different orientations of components in use or operation in addition to the orientation shown in the drawings. For example, when a component shown in the drawing is turned over, a component described as “beneath” or “beneath” of another component may be placed “above” of the other component. can Accordingly, the exemplary term “below” may include both directions below and above. Components may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to orientation.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. As used herein, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, "comprises" and/or "comprising" means that a referenced component, step and/or action excludes the presence or addition of one or more other components, steps and/or actions. I never do that.

Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly specifically defined.

In the drawings, the thickness or size of each component is exaggerated, omitted, or schematically illustrated for convenience and clarity of description. In addition, the size and area of each component do not fully reflect the actual size or area.

The suffixes "module" and "~ part" for the components used in the following description are given or mixed in consideration of only the ease of writing the specification, and do not have a meaning or role distinct from each other by themselves.

At this time, it will be understood that each block of the flowchart diagrams and combinations of the flowchart diagrams may be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, such that the instructions performed by the processor of the computer or other programmable data processing equipment are not described in the flowchart block(s). It creates a means to perform functions. These computer program instructions may also be stored in a computer-usable or computer-readable memory that may direct a computer or other programmable data processing equipment to implement a function in a particular manner, and thus the computer-usable or computer-readable memory. It is also possible that the instructions stored in the flow chart block(s) produce an article of manufacture containing instruction means for performing the function described in the flowchart block(s). The computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to create a computer or other programmable data processing equipment. It is also possible that instructions for performing the processing equipment provide steps for performing the functions described in the flowchart block(s).

Additionally, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative implementations it is also possible for the functions recited in blocks to occur out of order. For example, two blocks shown one after another may in fact be performed substantially simultaneously, or it is possible that the blocks are sometimes performed in the reverse order according to the corresponding function.

Also, in this specification, terms such as first and second may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another.

1 is a diagram illustrating the configuration of an air conditioner according to an embodiment of the present invention.

Referring to FIG. 1 , the air conditioner 100 according to an embodiment of the present invention may include an indoor unit 31 and an outdoor unit 21 connected to the indoor unit 31 .

The indoor unit 31 of the air conditioner may be any of a stand-type air conditioner, a wall-mounted air conditioner, and a ceiling-type air conditioner, but in the drawings, the stand-type indoor unit 31 is exemplified.

Meanwhile, the air conditioner 100 may further include at least one of a ventilator, an air purifier, a humidifier, and a heater, and may operate in conjunction with the operation of the indoor unit and the outdoor unit.

The outdoor unit 21 includes a compressor (not shown) that receives and compresses a refrigerant, an outdoor heat exchanger (not shown) that exchanges heat between the refrigerant and outdoor air, and an accumulator (not shown) that extracts a gaseous refrigerant from the supplied refrigerant and supplies it to the compressor. ), and/or may include a four-way valve (not shown) for selecting a flow path of the refrigerant according to the heating operation. In addition, the outdoor unit 21 may further include a plurality of valves, an oil recovery unit, and the like, but a description of the configuration thereof will be omitted below.

The outdoor unit 21 may include a plurality of sensors (not shown), and a detailed description thereof will be described with reference to FIG. 3 .

The outdoor unit 21 may operate a compressor and an outdoor heat exchanger to compress or heat exchange the refrigerant according to a setting to supply the refrigerant to the indoor unit 31 . The outdoor unit 21 may be driven by a remote controller (not shown) or a demand from the indoor unit 31 . In this case, as the cooling/heating capacity is varied in response to the driven indoor unit, the number of outdoor units and the number of compressors installed in the outdoor unit may vary. In this case, the outdoor unit 21 may supply the compressed refrigerant to the connected indoor unit 31 .

The indoor unit 31 may receive refrigerant from the outdoor unit 21 and discharge cold and hot air into the room. The indoor unit 31 may include an indoor heat exchanger (not shown), an indoor unit fan (not shown), an expansion valve (not shown) through which the supplied refrigerant is expanded, and/or a plurality of sensors (not shown).

At this time, the outdoor unit 21 and the indoor unit 31 are connected through a communication line to transmit and receive data, and are connected to a remote controller (not shown) by wire or wirelessly, and operate according to the control of the remote controller (not shown). can do.

A remote controller (not shown) may be connected to the indoor unit 31 , input a user's control command to the indoor unit 31 , and receive and display status information of the indoor unit 31 . In this case, the remote control may communicate with the indoor unit 31 by wire or wirelessly depending on the connection type.

FIG. 2 is a schematic diagram of the outdoor unit and indoor unit of FIG. 1 , and FIG. 3 is a diagram schematically illustrating an internal structure of the ejector.

Referring to FIG. 2 , the air conditioner 100 according to an embodiment of the present invention may be largely divided into an outdoor unit 21 and an indoor unit 31 .

The outdoor unit 21 includes a compressor 102 serving to compress a refrigerant, a compressor motor 102b for driving the compressor 102, an outdoor heat exchanger 104 serving to radiate heat from the compressed refrigerant, and an outdoor unit. An outdoor blower 105 comprising an outdoor fan 105a disposed on one side of the heat exchanger 104 to promote heat dissipation of the refrigerant and a motor 105b for an outdoor fan rotating the outdoor fan 105a, which expands the condensed refrigerant The main expansion mechanism 106 (eg, electronic expansion valves (EEV)), the cooling/heating switching valve 110 that changes the flow path of the compressed refrigerant, temporarily stores the vaporized refrigerant to remove moisture and foreign substances. Then, it may include an accumulator 103 that supplies a refrigerant of a constant pressure to the compressor.

The outdoor unit 21 may further include an ejector 111 including a first inlet 112 , a second inlet 113 , and an outlet 114 . The ejector 111 may mix and discharge the fluid introduced through the first inlet 112 and the fluid introduced through the second inlet 113 .

The first inlet 112 of the ejector 111 may be connected to a flow path through which the refrigerant discharged from the compressor 102 flows so that the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 102 flows. The second inlet 113 of the ejector 111 may be connected to the accumulator 103 so that the liquid refrigerant recovered from the accumulator 103 flows, and may be connected to the first flow path 121 through which the liquid refrigerant flows.

In this case, the ejector 111 may discharge a mixed refrigerant obtained by mixing the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 102 and the liquid refrigerant recovered from the accumulator 103 .

Referring to FIG. 3 , the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 102 may be introduced into the ejector 111 through the first inlet 112 and pass through the nozzle unit 310 at high speed. In this case, the flow rate of the gaseous refrigerant introduced through the first inlet 112 may increase while passing through the nozzle 310 , and the pressure may decrease. Meanwhile, according to the pressure of the gaseous refrigerant lowered while passing through the nozzle unit 310 , the liquid refrigerant recovered from the accumulator 103 may be introduced into the second inlet unit 113 by a pressure difference.

The gaseous refrigerant ejected through the nozzle unit 310 and the liquid refrigerant introduced through the second inlet 113 may be mixed in the mixing unit 320, and the mixed refrigerant in which the gaseous refrigerant and the liquid refrigerant are mixed As it passes through the diffuser unit 330 , the flow rate decreases and the pressure increases, so that it may be discharged from the ejector 111 through the discharge unit 114 . The mixed refrigerant discharged from the ejector 111 may be injected into the compressor 102 through the second flow path 122 . For example, the mixed refrigerant discharged from the ejector 111 may be injected into the compressor 102 through an injection unit (not shown) of the compressor 102 . As the mixed refrigerant discharged from the ejector 111 is injected into the compressor 102 , it is possible to reduce the operating load of the compressor 102 and increase the flow rate of the refrigerant flowing to the compressor 102 , etc. capacity can be obtained.

Meanwhile, a first valve 115 for controlling the flow rate of the fluid may be disposed in the first flow path 121 , and a second valve 116 for controlling the flow rate of the fluid may be disposed in the second flow path 122 . can be The first valve 115 and the second valve 116 may be an electronic expansion valve (EEV).

A check valve 117 for allowing the fluid to flow in one direction may be further disposed in the first flow path 121 . That is, in the first flow path 121 , the fluid can flow from the accumulator 103 to the ejector 111 by the check valve 117 , and the reverse flow from the ejector 111 to the accumulator 103 can be blocked. there is.

The indoor unit 31 includes an indoor heat exchanger 108 disposed indoors to perform a cooling/heating function, an indoor fan 109a disposed at one side of the indoor heat exchanger 108 to promote heat dissipation of the refrigerant, and an indoor unit. It may include an indoor blower 109 including a motor 109b for an indoor fan that rotates the fan 109a.

At least one indoor heat exchanger 108 may be installed. At least one of an inverter compressor and a constant speed compressor may be used as the compressor 102 .

In addition, the air conditioner 100 may be configured as an air conditioner for cooling the room, or may be configured as a heat pump for cooling or heating the room.

4 is a block diagram of an air conditioner according to an embodiment of the present invention.

Referring to FIG. 4 , the air conditioner 100 may include a fan driving unit 410 , a compressor driving unit 420 , a sensor unit 430 , a valve unit 440 , and/or a control unit 450 . The air conditioner 100 according to various embodiments of the present invention may further include various components not shown in FIG. 3 .

The fan driving unit 410 may drive a fan provided in the air conditioner 100 . For example, the fan driving unit 410 may drive the outdoor fan 105a and/or the indoor fan 109a.

The fan driving unit 410 includes a rectifying unit (not shown) that rectifies and outputs AC power into DC power, a dc stage capacitor for storing the pulsating voltage from the rectifier, and a plurality of switching elements, and provides a smoothed DC power supply with a predetermined frequency. The inverter may include an inverter (not shown) that converts and outputs the three-phase AC power and/or a motor that drives the fan according to the three-phase AC power output from the inverter.

On the other hand, the fan driving unit 410 may have a configuration for driving the outdoor fan 105a and the indoor fan 109a separately.

The fan driving unit 410 may change the rotation speed of the fan according to the control of the controller 450 . For example, the fan driving unit 410 may change the frequency of the three-phase AC power output to the outdoor fan motor 105b under the control of the controller 450 to change the rotation speed of the outdoor fan 105a. there is. For example, the fan driving unit 410 may change the frequency of the three-phase AC power output to the indoor fan motor 109b to change the rotation speed of the indoor fan 109a under the control of the controller 450 . there is.

The compressor driving unit 420 may drive the compressor 102 . For example, the compressor driving unit 420 includes a rectifying unit (not shown) for rectifying AC power into DC power and outputting it, a dc terminal capacitor for storing the pulsating voltage from the rectifying unit, and a plurality of switching elements, and a smoothed direct current It may include an inverter (not shown) that converts power to three-phase AC power of a predetermined frequency and outputs, and/or a compressor motor 102b that drives the compressor 102 according to the three-phase AC power output from the inverter there is.

The compressor driving unit 420 may change the operating frequency of the compressor 102 under the control of the control unit 450 . For example, the compressor driving unit 420 may change the operating frequency of the compressor 102 by changing the frequency of the three-phase AC power output to the compressor motor 102b under the control of the control unit 450 . .

The sensor unit 430 may include a plurality of sensors, and may transmit data on detection values detected through the plurality of sensors to the controller 450 . For example, the sensor unit 430 is disposed inside the outdoor heat exchanger 104 and includes a heat exchanger temperature sensor (not shown) that detects a condensation temperature or an evaporation temperature, and each pipe of the air conditioner 100 . A pressure sensor (not shown) for detecting the pressure of the refrigerant flowing through the pipe temperature sensor (not shown) for detecting the temperature of the refrigerant flowing through each pipe of the air conditioner 100, It may include an indoor temperature sensor (not shown), an outdoor temperature sensor (not shown) for detecting the outdoor temperature, and the like.

The valve unit 440 may include at least one valve. At least one valve included in the valve unit 440 may operate under the control of the controller 450 . For example, the valve unit 440 may include a cooling/heating switching valve 110 , a first valve 115 , and/or a second valve 116 .

The controller 450 may be connected to each component provided in the air conditioner 100 and may control the overall operation of each component. The controller 450 may transmit/receive data to and from each component provided in the air conditioner 100 .

The controller 450 may include at least one processor. Here, the processor may be a general processor such as a central processing unit (CPU). Of course, the processor may be a dedicated device such as an ASIC or other hardware-based processor.

The controller 450 may be provided in at least one of the indoor unit 31 and/or a central controller (not shown) as well as the outdoor unit 21 .

The controller 450 may check the operation mode of the air conditioner 100 , and may control the operation of each component provided in the air conditioner 100 according to the operation mode of the air conditioner 100 . . For example, when the operation mode of the air conditioner 100 is the heating operation mode in consideration of the amount of liquid refrigerant recovered from the accumulator 103 , the control unit 450 may include the first valve 115 and the second valve 115 . The valve 116 may be controlled to be opened, and in the cooling operation mode, the first valve 115 and the second valve 116 may be controlled to be closed.

The controller 450 may acquire data related to each configuration provided in the air conditioner 100 . In this case, the controller 450 may acquire data related to each configuration provided in the air conditioner 100 at a predetermined time interval according to a predetermined period in consideration of the computational load. Here, the data related to each component included in the air conditioner 100 includes the operating frequency of the compressor 102 , the discharge temperature of the compressor 102 , the inlet pipe temperature of the outdoor heat exchanger 104 , and the outdoor heat exchange. The outlet pipe temperature of the unit 104 , the inlet pipe temperature of the indoor heat exchanger 108 , the pipe temperature of the second flow path 122 connected to the compressor 102 , and the outlet pipe of the indoor heat exchanger 108 . Temperature, the suction pressure of the indoor heat exchanger 108 , the discharge pressure of the indoor heat exchanger 108 , the opening degree of the main expansion mechanism 106 , the opening degree of the first valve 115 , and the second valve 116 . may include the amount of opening of

The control unit 450 may control the operation of at least one valve included in the valve unit 440 based on data related to each configuration provided in the air conditioner 100 .

The controller 450 may control the operation of the first valve 115 and/or the second valve 116 according to the temperature of the mixed refrigerant discharged from the ejector 111 . For example, the control unit 450 may check the temperature of the mixed refrigerant based on the pipe temperature of the second flow path 122 .

The controller 450 may calculate a target temperature of the mixed refrigerant discharged from the ejector 111 based on data related to each configuration provided in the air conditioner 100 . Here, the target temperature may be the temperature of the mixed refrigerant corresponding to the optimum pressure of the gaseous refrigerant injected and injected into the compressor 102 , which is optimized to maximize the efficiency of the compressor 102 . For example, in the heating operation mode, the control unit 450 relates to the temperature of the refrigerant flowing into the outdoor heat exchanger 104 , the temperature of the refrigerant discharged from the indoor heat exchanger 108 , and the operating frequency of the compressor 102 . Based on the data and/or the pressure of the refrigerant flowing into the indoor heat exchanger 108 , the target temperature of the mixed refrigerant discharged from the ejector 111 may be calculated. In this case, the controller 450 may include a temperature of the refrigerant flowing into the outdoor heat exchanger 104 , a temperature of the refrigerant discharged from the indoor heat exchanger 108 , data regarding the operating frequency of the compressor 102 , and/or indoor heat exchange. The target temperature of the mixed refrigerant discharged from the ejector 111 may be calculated based on a regression equation based on the pressure of the refrigerant flowing into the unit 108 .

The controller 450 may compare the calculated target temperature with the temperature of the mixed refrigerant, and may control the operation of the first valve 115 and/or the second valve 116 based on the comparison result.

When the temperature of the mixed refrigerant is equal to or less than the target temperature, the controller 450 may determine whether the temperature of the mixed refrigerant is less than the minimum reference temperature. Here, the minimum reference temperature may mean a temperature corresponding to the minimum temperature at which the liquid refrigerant is not injected into the compressor 102 , which is lower than the target temperature, and may be set by the user. For example, the lowest reference temperature may be a temperature 1°C lower than the target temperature.

When the temperature of the mixed refrigerant is equal to or greater than the minimum temperature and equal to or less than the target temperature, the controller 450 may control the opening degrees of the first valve 115 and the second valve 116 to be maintained.

When the temperature of the mixed refrigerant is less than the minimum reference temperature, the controller 450 may control the opening amount of the first valve 115 to be small. At this time, when the opening amount of the first valve 115 is reduced, the amount of liquid refrigerant flowing into the ejector 111 is reduced, and the temperature of the mixed refrigerant may increase.

When the temperature of the mixed refrigerant exceeds the target temperature, the controller 450 may determine whether the flow rate of the mixed refrigerant is insufficient. For example, when the flow rate of the mixed refrigerant is insufficient, the discharge temperature of the compressor 102 is increased, and the temperature of the gaseous refrigerant flowing into the ejector 111 is increased. As a result, the temperature of the mixed refrigerant may also be excessively high.

When the flow rate of the mixed refrigerant is insufficient, the control unit 450 controls the first valve 115 and the second valve 116 to increase the flow rate of the mixed refrigerant delivered to the compressor 102 through the second flow path 122 . can be controlled to increase the opening degree of Meanwhile, when the flow rate of the mixed refrigerant is not insufficient, the controller 450 may control the opening amount of the first valve 115 to increase. At this time, when the opening amount of the first valve 115 is increased while the opening amount of the second valve 116 is maintained, the inflow amount of the liquid refrigerant flowing into the ejector 111 increases, so that the temperature of the mixed refrigerant may decrease. there is.

5A and 5B are flowcharts illustrating a method of operating an air conditioner according to an embodiment of the present invention.

Referring to FIG. 5A , in operation S510 , the air conditioner 100 may determine whether the operation mode of the air conditioner 100 is the heating operation mode.

In operation S520 , the air conditioner 100 may control the first valve 115 and the second valve 116 to be opened when the operation mode is the heating operation mode. In this case, the first valve 115 and the second valve 116 may be opened according to a preset initial opening amount.

The air conditioner 100 may acquire data related to each configuration provided in the air conditioner 100 in operation S530, and target temperature of the mixed refrigerant discharged from the ejector 111 based on the acquired data. can be calculated. For example, in the air conditioner 100 , the operating frequency of the compressor 102 , the discharge temperature of the compressor 102 , the inlet piping temperature of the outdoor heat exchanger 104 , and the outlet of the outdoor heat exchanger 104 . side pipe temperature, the inlet pipe temperature of the indoor heat exchanger 108 , the pipe temperature of the second flow path 122 connected to the compressor 102 , the outlet pipe temperature of the indoor heat exchanger 108 , the indoor heat exchanger Data on the suction pressure of 108 , the discharge pressure of the indoor heat exchanger 108 , the opening degree of the main expansion mechanism 106 , the opening degree of the first valve 115 , the opening degree of the second valve 116 , etc. can be obtained, and the target temperature of the mixed refrigerant can be calculated based on the obtained data.

The air conditioner 100 may control the operations of the first valve 115 and the second valve 116 according to the temperature of the mixed refrigerant in operation S540 . In this case, the air conditioner 100 may check the temperature of the mixed refrigerant based on the pipe temperature of the second flow path 122 .

Referring to FIG. 5B , in operation S541 , the air conditioner 100 may compare the target temperature calculated in operation S530 with the temperature of the mixed refrigerant. For example, the air conditioner 100 may determine whether the temperature of the mixed refrigerant exceeds a target temperature.

In operation S542 , the air conditioner 100 may determine whether the flow rate of the mixed refrigerant is insufficient when the temperature of the mixed refrigerant exceeds the target temperature. For example, the air conditioner 100 may determine that the flow rate of the mixed refrigerant is insufficient when the opening amount of the second valve 116 is equal to or less than a preset minimum opening amount.

When it is determined that the flow rate of the mixed refrigerant is insufficient in operation S543 , the air conditioner 100 may control the opening amounts of the first valve 115 and the second valve 116 to increase. In this case, the air conditioner 100 may control the opening amount of the first valve 115 and the second valve 116 to be increased by a preset opening amount.

Meanwhile, when it is determined that the flow rate of the mixed refrigerant is not insufficient in operation S544 , the air conditioner 100 may determine whether the opening degree of the first valve 115 is the maximum.

In operation S545, when the opening degree of the first valve 115 is the maximum, the air conditioner 100 determines that the temperature of the refrigerant discharged from the compressor 102 is higher than a predetermined standard, and determines that an error has occurred. can do. In this case, the air conditioner 100 may control the operating frequency of the compressor 102 to be lowered according to a preset standard.

Meanwhile, in operation S546 , when the opening amount of the first valve 115 is not the maximum, the air conditioner 100 may control the opening amount of the first valve 115 to increase. At this time, when the opening amount of the first valve 115 is increased while the opening amount of the second valve 116 is maintained, the inflow amount of the liquid refrigerant flowing into the ejector 111 increases, so that the temperature of the mixed refrigerant may decrease. there is.

Meanwhile, in operation S547 , the air conditioner 100 may determine whether the temperature of the mixed refrigerant is less than the minimum reference temperature when the temperature of the mixed refrigerant is less than or equal to the target temperature. For example, the lowest reference temperature may be a temperature 1°C lower than the target temperature.

In operation S548, when the temperature of the mixed refrigerant is less than the minimum reference temperature, the air conditioner 100 may control the opening amount of the first valve 115 to be small. At this time, when the opening amount of the first valve 115 is reduced, the amount of liquid refrigerant flowing into the ejector 111 is reduced, and the temperature of the mixed refrigerant may increase.

Meanwhile, in operation S549, when the temperature of the mixed refrigerant is equal to or greater than the minimum temperature and equal to or less than the target temperature, the air conditioner 100 may control the opening amount of the first valve 115 and the second valve 116 to be maintained. .

Referring back to FIG. 5A , the air conditioner 100 may determine whether the heating operation mode is terminated in operation S550 . For example, when the operation mode of the air conditioner 100 is changed from the heating operation mode to the cooling operation mode, or when the power of the air conditioner 100 is turned off, the heating operation mode is terminated. can judge

When the operation mode of the air conditioner 100 is maintained in the heating operation mode, the air conditioner 100 branches to operation S530 and ejects the ejector based on data related to each configuration provided in the air conditioner 100 . The target temperature of the mixed refrigerant discharged in (111) can be calculated.

On the other hand, the air conditioner 100, in operation S560, when the operation mode of the air conditioner 100 is not the heating operation mode, considering that the amount of liquid refrigerant recovered from the accumulator 103 is not sufficient. , the first valve 115 and the second valve 116 may be controlled to be closed.

6 is a diagram illustrating a P-H diagram showing a state of a refrigerant of an air conditioner using a gas phase refrigerant injection cycle according to an embodiment of the present invention.

Referring to FIG. 6 , the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 102 is condensed in the indoor heat exchanger 108 , expanded in the main expansion mechanism 106 , and in the outdoor heat exchanger 104 . It can be moved from 'a' to 'b' on the PH diagram through the evaporation of .

On the other hand, some of the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 102 may be introduced into the ejector 111 through the first inlet 112 , and the liquid refrigerant recovered from the accumulator 103 is the second It may be introduced into the ejector 111 through the inlet 113 . At this time, the liquid refrigerant recovered from the accumulator 103 may be located at 'c' on the P-H diagram.

The gaseous refrigerant introduced through the first inlet 112 may move from 'a' to 'd' on the P-H diagram by increasing the flow rate and decreasing the pressure while passing through the nozzle unit 310 .

Meanwhile, the gaseous refrigerant introduced through the first inlet 112 and the liquid refrigerant introduced through the second inlet 113 may be mixed in the mixing unit 320 . At this time, the mixed refrigerant mixed in the mixing unit 320 may be located at 'e' on the P-H diagram.

The mixed refrigerant in which the gaseous refrigerant and the liquid refrigerant are mixed may be discharged from the ejector 111 through the discharging unit 114 through the diffuser unit 330 . At this time, as the mixed refrigerant passes through the diffuser unit 330 , the flow rate is decreased and the pressure is increased, so that it can move from 'e' to 'f' on the PH diagram, and the compressor 102 through the second flow path 122 ) can be injected and sprayed. On the other hand, as the mixed refrigerant is injected and injected into the compressor 102, the discharge temperature of the compressor 102 is lowered compared to the case where the mixed refrigerant is not injected and injected into the compressor 102, and moves to 'a' on the PH diagram it can be confirmed that

As described above, according to various embodiments of the present invention, through a gas phase refrigerant injection cycle using the liquid refrigerant recovered from the accumulator 103, without a configuration such as a supercooler or a flash tank, the refrigerant flowing through the condenser, the evaporator, etc. It is possible to increase the flow rate of the compressor 102, it is possible to lower the discharge temperature of the compressor 102, it is possible to improve the operating efficiency during the heating operation, it is possible to expand the operating range. In addition, it is possible to secure price competitiveness while solving the problems that heating capacity and COP (Coefficient of Performance) decrease as compression efficiency and refrigerant flow rate decrease in cold regions and cold regions.

The accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and the technical spirit disclosed herein is not limited by the accompanying drawings, and all changes and equivalents included in the spirit and scope of the present invention It should be understood to include water or substitutes.

Likewise, although acts are depicted in the drawings in a particular order, it should not be construed that such acts must be performed in that particular order or sequential order shown, or that all depicted acts must be performed in order to achieve desirable results. . In certain cases, multitasking and parallel processing may be advantageous.

In addition, although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above, and the technical field to which the present invention belongs without departing from the gist of the present invention as claimed in the claims In addition, various modifications are possible by those of ordinary skill in the art, and these modifications should not be individually understood from the technical spirit or perspective of the present invention.

Claims (9)

In the air conditioner,
a compressor for compressing and discharging the refrigerant;
an accumulator for recovering the liquid refrigerant contained in the refrigerant flowing into the compressor; and
an ejector for discharging the mixed refrigerant by mixing the refrigerant discharged from the compressor and the liquid refrigerant recovered from the accumulator;
The mixed refrigerant discharged from the ejector is injected into the compressor. According to claim 1,
a first valve installed in a first flow path connecting the accumulator and the ejector to control a flow rate of the liquid refrigerant delivered to the ejector; and
a second valve installed in a second flow path connecting the discharge unit of the ejector through which the mixed refrigerant is discharged and the injection unit of the compressor through which the mixed refrigerant is injected, to control the flow rate of the mixed refrigerant delivered to the compressor; Air conditioner, characterized in that it further comprises. 3. The method of claim 2,
and a check valve installed in the second flow path to allow the liquid refrigerant to flow in one direction. 4. The method of claim 3,
a temperature sensor for sensing a temperature of the mixed refrigerant injected into the compressor; and
Further comprising a control unit for controlling the operation of the first valve and the second valve,
The control unit is
When the operation mode of the air conditioner is a heating operation mode, based on the temperature of the mixed refrigerant, the operation of the first valve and the second valve are controlled,
and controlling the first valve and the second valve to be closed when the operation mode of the air conditioner is not the heating operation mode. 5. The method of claim 4,
The control unit is
When the operation mode of the air conditioner is a heating operation mode, data for each configuration provided in the air conditioner is obtained,
Based on the data for each configuration, calculating the target temperature,
and comparing the calculated target temperature with the temperature of the mixed refrigerant to control the operation of the first valve and the second valve. 6. The method of claim 5,
The control unit is
If the temperature of the mixed refrigerant is less than or equal to the target temperature, it is determined whether the temperature of the mixed refrigerant is less than a minimum reference temperature that is lower than the target temperature by a predetermined temperature,
When the temperature of the mixed refrigerant is equal to or higher than the minimum reference temperature, controlling the opening degrees of the first valve and the second valve to be maintained,
The air conditioner according to claim 1, wherein when the temperature of the mixed refrigerant is less than the minimum reference temperature, the opening degree of the first valve is controlled to be small. 7. The method of claim 6,
The control unit is
When the temperature of the mixed refrigerant exceeds the target temperature, it is determined whether the flow rate of the mixed refrigerant is insufficient,
When the flow rate of the mixed refrigerant is insufficient, controlling the opening degree of the first valve and the second valve to increase,
The air conditioner according to claim 1, wherein when the flow rate of the mixed refrigerant is not insufficient, the opening degree of the first valve is controlled to increase. 8. The method of claim 7,
The control unit, when the temperature of the mixed refrigerant exceeds the target temperature,
When the opening amount of the second valve corresponds to the minimum opening amount, it is determined that the flow rate of the mixed refrigerant is insufficient,
and when the opening amount of the second valve exceeds the minimum opening amount and the opening amount of the first valve is less than the maximum opening amount, it is determined that the flow rate of the mixed refrigerant is not insufficient. 9. The method of claim 8,
The data for each configuration includes, in the heating operation mode, data on the temperature of the refrigerant flowing into the outdoor heat exchanger, data on the temperature of the refrigerant discharged from the indoor heat exchanger, data on the operating frequency of the compressor, and the Air conditioner, characterized in that it includes data on the pressure of the refrigerant flowing into the indoor heat exchanger.

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