CN113865013A

CN113865013A - Variable-load adjusting air conditioning system and control method thereof

Info

Publication number: CN113865013A
Application number: CN202111265943.3A
Authority: CN
Inventors: 皇甫启捷; 黄明月; 梁祥飞; 黄泽清; 徐璐
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2021-10-28
Filing date: 2021-10-28
Publication date: 2021-12-31
Anticipated expiration: 2041-10-28
Also published as: CN113865013B

Abstract

The present disclosure provides a variable load adjustment air conditioning system and a control method thereof, the variable load adjustment air conditioning system including: the outdoor heat exchanger can be controlled to be opened, and the outdoor third heat exchanger can be controlled to be closed when the load is greater than or equal to a first preset value; and when the load is less than or equal to a second preset value, the second outdoor heat exchanger can be controlled to be closed, and the third outdoor heat exchanger can be controlled to be opened, wherein the first preset value is more than or equal to the second preset value. According to the method, a component separation method can be adopted, so that the capacity of the non-azeotropic working medium is adjusted under different working conditions, the energy efficiency of the system is improved, meanwhile, the operating range of the working conditions of the system is widened, the efficient operation under different loads is realized, and the heat exchange efficiency is improved while the capacity of the system is adjusted; the problems that the outdoor unit of the system is frosted under severe working conditions, and the comfort of the indoor environment is reduced when defrosting and defrosting are carried out can be solved.

Description

Variable-load adjusting air conditioning system and control method thereof

Technical Field

The disclosure relates to the technical field of air conditioners, in particular to a variable load adjusting air conditioning system and a control method thereof.

Background

When the non-azeotropic working medium is applied to an air conditioning system, from the perspective of system circulation, the non-azeotropic mixed working medium can approach Lorenz circulation in the heat exchange process due to temperature slippage and temperature-enthalpy nonlinear relation in the heat exchange process, so that the circulation efficiency is improved. However, from the perspective of heat exchange, the heat transfer of the non-azeotropic working medium is deteriorated due to mass transfer resistance in the heat exchange process, the heat exchange coefficients of evaporation and condensation are all smaller than those of the pure working medium, and the larger the slippage temperature of the non-azeotropic working medium is, the more obvious the heat exchange performance is deteriorated.

Because the mixed working medium air-conditioning circulation system in the prior art has the technical problems that the heat exchange efficiency is low when the working condition load changes, better heat exchange efficiency cannot be obtained when various working conditions are met, the system operation efficiency is low, various changing working condition loads cannot be met, and the like, the variable-load adjusting air-conditioning system and the control method thereof are researched and designed.

BRIEF SUMMARY OF THE PRESENT DISCLOSURE

Therefore, the technical problem to be solved by the present disclosure is to overcome the defect that the heat exchange efficiency of the mixed working medium air conditioning circulation system is low when the working condition load changes, which results in lower system operation energy efficiency, in the prior art, thereby providing a variable load regulation air conditioning system and a control method thereof.

In order to solve the above problems, the present disclosure provides a variable load adjustment air conditioning system, which includes:

the air-conditioning system comprises a compressor, an outdoor first heat exchanger, an outdoor second heat exchanger, an outdoor third heat exchanger, an indoor first heat exchanger and a gas-liquid separator, wherein the gas-liquid separator comprises a first end, a second end and a third end, the air-conditioning system comprises a first boiling point refrigerant and a second boiling point refrigerant, the boiling point of the first boiling point refrigerant is less than that of the second boiling point refrigerant, one end of the outdoor first heat exchanger can be communicated to an exhaust end or a suction end of the compressor, and the other end of the outdoor first heat exchanger can be communicated to the first end of the gas-liquid separator;

the second end is a gas end, the gas separated from the gas-liquid separator can be communicated with one end of the outdoor second heat exchanger through the second end, the third end is a liquid end, and the liquid separated from the gas-liquid separator can be communicated with one end of the outdoor third heat exchanger through the third end;

the other end of the outdoor second heat exchanger and the other end of the outdoor third heat exchanger can be communicated with the fourth end of the indoor first heat exchanger after being mixed, and the fifth end of the indoor first heat exchanger can be communicated to the suction end or the exhaust end of the compressor;

when the load is larger than or equal to a first preset value, the outdoor second heat exchanger can be controlled to be opened, and the outdoor third heat exchanger can be controlled to be closed; when the load is less than or equal to a second preset value, the outdoor second heat exchanger can be controlled to be closed, the outdoor third heat exchanger can be controlled to be opened, and the first preset value is greater than or equal to the second preset value;

the other end of the outdoor second heat exchanger is converged with the other end of the outdoor third heat exchanger and then communicated to one end of the first throttling device through the seventh pipeline, the other end of the first throttling device is communicated to the fourth end of the indoor first heat exchanger through the eighth pipeline, and the fifth end of the indoor first heat exchanger is communicated to the suction end or the exhaust end of the compressor through the ninth pipeline;

the pipeline system also comprises a thirteenth pipeline and a fourteenth pipeline, wherein one end of the thirteenth pipeline is communicated with the fourth end, the other end of the thirteenth pipeline is communicated to the ninth pipeline, one end of the fourteenth pipeline is communicated with the fifth end, and the other end of the fourteenth pipeline is communicated to the eighth pipeline.

In some embodiments, the system further comprises a third control valve, a fourth control valve, a fifth control valve and a sixth control valve, wherein the third control valve is arranged on the pipe section between the eighth pipeline and the fourth end, the fourth control valve is arranged on the thirteenth pipeline, the fifth control valve is arranged on the fourteenth pipeline, and the sixth control valve is arranged on the pipe section between the ninth pipeline and the fifth end.

In some embodiments, the first end and the third end are both located at the bottom of the gas-liquid separator and the second end is located above half the height of the gas-liquid separator.

In some embodiments, one end of the outdoor first heat exchanger is communicated to a discharge end or a suction end of the compressor through a first pipeline, the other end is communicated to the first end of the gas-liquid separator through a second pipeline, the second end of the gas-liquid separator is communicated with one end of the outdoor second heat exchanger through a third pipeline, and the third end is communicated with one end of the outdoor third heat exchanger through a fourth pipeline.

In some embodiments, the other end of the outdoor second heat exchanger is communicated to one end of a fifth pipeline, the other end of the outdoor third heat exchanger is communicated to one end of a sixth pipeline, the other end of the fifth pipeline is merged with the other end of the sixth pipeline, the fifth pipeline is provided with a first control valve, and the sixth pipeline is provided with a second control valve;

when the load is larger than or equal to a first preset value, the first control valve is opened by controlling the outdoor second heat exchanger to be opened, and the second control valve is closed by controlling the outdoor third heat exchanger to be closed; when the load is less than or equal to a second preset value, the mode of controlling the outdoor second heat exchanger to be closed is to close the first control valve, and the mode of controlling the outdoor third heat exchanger to be opened is to open the second control valve.

In some embodiments, the air conditioner further comprises a first throttling device, a seventh pipeline, an eighth pipeline and a ninth pipeline, wherein the fifth pipeline is merged with the sixth pipeline and then communicated to one end of the first throttling device through the seventh pipeline, the other end of the first throttling device is communicated to one end of the indoor first heat exchanger through the eighth pipeline, and the other end of the indoor first heat exchanger is communicated to the air suction end or the air exhaust end of the compressor through the ninth pipeline.

In some embodiments, the air conditioner further comprises a four-way valve, the four-way valve comprises an E end, an S end, a C end and a D end, the E end is communicated with the ninth pipeline, the S end is communicated with the air suction end of the compressor, the C end is communicated with the first pipeline, the D end is communicated with the air discharge end of the compressor, and the first communication state of the four-way valve is as follows: the end E is communicated with the end S, the end C is communicated with the end D, at the moment, the indoor operation is in a refrigerating state, and the second communication state of the four-way valve is as follows: the end E is communicated with the end D, the end S is communicated with the end C, and at the moment, the indoor operation is in a heating state; the four-way valve can be switched between the first communication state and the second communication state.

In some embodiments, the system further comprises a tenth pipeline and an indoor second heat exchanger, wherein one end of the tenth pipeline is communicated with the first pipeline and penetrates into the gas-liquid separator for heat exchange, and the other end of the tenth pipeline is communicated to one end of the indoor second heat exchanger.

In some embodiments, the indoor heat exchanger further comprises an eleventh pipeline and a second throttling device, the other end of the indoor second heat exchanger is communicated to the eighth pipeline through the eleventh pipeline, and the eleventh pipeline is provided with the second throttling device;

or the other end of the indoor second heat exchanger is communicated to one end of the indoor third heat exchanger through an eleventh pipeline, the eleventh pipeline is provided with a second throttling device, and the other end of the indoor third heat exchanger is communicated to the ninth pipeline through a twelfth pipeline.

In some embodiments, the portion of the tubing that extends into the gas-liquid separator through the tenth conduit is fluidly sealed from communication with the interior of the gas-liquid separator; and/or the part of the pipe section, penetrating into the gas-liquid separator, of the tenth pipeline is a serpentine pipe section.

In some embodiments, the air conditioner further comprises a first fan, wherein the first fan can drive the air flow in the chamber to firstly flow through the first indoor heat exchanger and then flow through the second indoor heat exchanger, namely, the second indoor heat exchanger is positioned at the downstream side of the first indoor heat exchanger along the air flow direction.

In some embodiments, when further comprising an indoor third heat exchanger, the first fan is capable of driving an indoor air flow through the indoor first heat exchanger, the indoor third heat exchanger, and the indoor second heat exchanger in sequence.

In some embodiments, further comprising a second fan:

the second fan can drive outdoor airflow to flow through the outdoor second heat exchanger firstly and then flow through the outdoor first heat exchanger, namely the outdoor first heat exchanger is positioned on the downstream side of the outdoor second heat exchanger along the airflow flowing direction; and/or the second fan can drive outdoor airflow to firstly flow through the outdoor third heat exchanger and then flow through the outdoor first heat exchanger, namely the outdoor first heat exchanger is positioned on the downstream side of the outdoor third heat exchanger along the airflow flowing direction.

In some embodiments, the outdoor second heat exchanger and the outdoor third heat exchanger are located in parallel along the airflow flowing direction, that is, the outdoor second heat exchanger and the outdoor third heat exchanger are located in a cross section perpendicular to the airflow flowing direction.

The present disclosure also provides a method of controlling a variable load modulated air conditioning system as set forth in any of the preceding claims, comprising:

detecting the operation mode and the load working condition of the air conditioning system;

judging, namely judging the relation between the load working condition and the first preset value and the second preset value;

a control step, when the air conditioner is operated in a cooling mode: when the load is larger than or equal to a first preset value, the outdoor second heat exchanger is controlled to be opened, and the outdoor third heat exchanger is controlled to be closed; when the load is less than or equal to a second preset value, the outdoor second heat exchanger is controlled to be closed, and the outdoor third heat exchanger is controlled to be opened; when the load is smaller than the first preset value and the second preset value, the outdoor second heat exchanger is controlled to be opened, and the outdoor third heat exchanger is controlled to be opened; wherein the first preset value is more than or equal to the second preset value.

In some embodiments, when further comprising a first control valve and a second control valve:

in the control step, when the load is larger than or equal to a first preset value, the first control valve is opened, and the second control valve is closed; when the load is less than or equal to a second preset value, closing the first control valve and opening the second control valve; opening the first control valve and opening the second control valve when the second preset value is less than the load and less than the first preset value.

In some embodiments, the detecting step can also detect the outdoor ambient temperature T_{Outer cover}；

The judging step of judging T_{Outer cover}The relationship between the first preset temperature and the second preset temperature and the fourth preset temperature, and whether the heating working condition is judged;

the control step comprises the following steps of: when the third preset temperature is less than or equal to T_{Outer cover}When the temperature is not higher than a fourth preset temperature, controlling the outdoor second heat exchanger and the outdoor third heat exchanger to be communicated; when T is_{Outer cover}When the temperature is lower than the third preset temperature, controlling the outdoor second switchThe heat exchanger and the outdoor third heat exchanger are alternately communicated.

in the control step, when the third preset temperature is less than or equal to T_{Outer cover}When the temperature is not higher than a fourth preset temperature, controlling the first control valve and the second control valve to be opened; when T is_{Outer cover}And when the temperature is lower than the third preset temperature, controlling the first control valve and the second control valve to be opened alternately.

In some embodiments, when a third control valve, a fourth control valve, a fifth control valve, and a sixth control valve are included,

in the control step, when the refrigeration mode is operated, the third control valve is controlled to be opened, the fourth control valve is controlled to be closed, the fifth control valve is controlled to be closed, and the sixth control valve is controlled to be opened; and when the heating mode is operated, the third control valve is controlled to be closed, the fourth control valve is controlled to be opened, the fifth control valve is controlled to be opened and the sixth control valve is controlled to be closed.

The variable load regulation air conditioning system and the control method thereof have the following beneficial effects:

the air conditioning system can select and control specific opening work of the outdoor second heat exchanger and the outdoor third heat exchanger according to the size of load working conditions, enables the outdoor second heat exchanger to work when the load is larger, adopts the low-boiling point refrigerant to evaporate and exchange heat, can increase the heat exchange effect in the refrigeration mode, has more circulating low-boiling point components in the system and larger volume refrigerating capacity, the refrigerating device can refrigerate the condition of large load (such as high indoor temperature); when the load is small, the outdoor third heat exchanger works, the high-boiling-point refrigerant is adopted for evaporation and heat exchange, the circulating high-boiling-point components in the system are more, the volume refrigerating capacity is small, and the refrigeration can be carried out under the condition of small load (such as low indoor temperature); by adopting a component separation method, the capacity of a non-azeotropic working medium under different working conditions is adjusted, the energy efficiency of the system is improved, the operating range of the working conditions of the system is expanded, the efficient operation under different loads is realized, the capacity adjustment of the system is realized, the heat exchange efficiency can be improved, and the heat exchange performance of the evaporation and condensation heat exchange processes of the system is improved; the problems that the outdoor unit of the system is frosted under severe working conditions, and the comfort of the indoor environment is reduced when defrosting and defrosting are carried out can be solved; the reheating technology is adopted, so that the air supply temperature can be effectively increased, and the comfort of air supply is improved.

Drawings

FIG. 1 is a schematic diagram of a non-azeotropic working medium system cycle (refrigeration mode) according to a main embodiment of the present disclosure;

FIG. 2 is a schematic diagram of the non-azeotropic working medium system cycle (heating mode) according to the main embodiment of the present disclosure;

FIG. 3 is a schematic diagram of the cycle of the non-azeotropic working medium system according to the main embodiment of the present disclosure (defrosting mode 1);

FIG. 4 is a schematic diagram of the cycle of the non-azeotropic working medium system according to the main embodiment of the present disclosure (defrosting mode 2);

FIG. 5 is a schematic view of a refrigeration mode cycle in accordance with an alternative embodiment of the present disclosure;

FIG. 6 is a schematic view of a heating mode cycle according to an alternative embodiment of the present disclosure;

FIG. 7 is a schematic view of a defrost mode cycle according to an alternative embodiment of the present disclosure;

fig. 8 is a schematic view of a defrosting mode cycle according to an alternative embodiment of the present disclosure.

The reference numerals are represented as:

10. a compressor; 21. an outdoor first heat exchanger; 22. an outdoor second heat exchanger; 23. an outdoor third heat exchanger; 31. a first throttling device; 32. a second throttling device; 41. an indoor first heat exchanger; 41a, a fourth end; 41b, a fifth end; 42. an indoor second heat exchanger; 43. an indoor third heat exchanger; 51. a gas-liquid separator; 51a, a first end; 51b, a second end; 51c, a third end; 61. a four-way valve; E. an E end; s, S end; C. a C terminal; D. a D end; 71. a first control valve; 72. a second control valve; 73. a third control valve; 74. a fourth control valve; 75. a fifth control valve; 76. a sixth control valve; 81. a first fan; 82. a second fan;

101. a first pipeline; 102. a second pipeline; 103. a third pipeline; 104. a fourth pipeline; 105. a fifth pipeline; 106. a sixth pipeline; 107. a seventh pipeline; 108. an eighth pipeline; 109. a ninth conduit; 110. a tenth pipeline; 111. an eleventh line; 112. a twelfth pipeline; 113. a thirteenth pipeline; 114. a fourteenth line.

Detailed Description

Primary embodiment, as shown in fig. 1-4, the present disclosure provides a variable load regulating air conditioning system comprising:

the air-conditioning system comprises a compressor 10, an outdoor first heat exchanger 21, an outdoor second heat exchanger 22, an outdoor third heat exchanger 23, an indoor first heat exchanger 41 and a gas-liquid separator 51, wherein the gas-liquid separator 51 comprises a first end 51a, a second end 51b and a third end 51c, the air-conditioning system comprises a first boiling point refrigerant and a second boiling point refrigerant, the boiling point of the first boiling point refrigerant is less than that of the second boiling point refrigerant, one end of the outdoor first heat exchanger 21 can be communicated to a gas discharge end or a gas suction end of the compressor 10, and the other end of the outdoor first heat exchanger 21 can be communicated to the first end 51a of the gas-liquid separator 51;

the second end 51b is a gas end, the gas separated in the gas-liquid separator 51 can be communicated with one end of the outdoor second heat exchanger 22 through the second end 51b, the third end 51c is a liquid end, and the liquid separated in the gas-liquid separator 51 can be communicated with one end of the outdoor third heat exchanger 23 through the third end 51 c;

the other end of the outdoor second heat exchanger 22 and the other end of the outdoor third heat exchanger 23 can be communicated with the fourth end 41a of the indoor first heat exchanger 41 after being mixed, and the fifth end 41b of the indoor first heat exchanger 41 can be communicated to the suction end or the exhaust end of the compressor 10;

when the load is greater than or equal to a first preset value, the outdoor second heat exchanger 22 can be controlled to be opened, and the outdoor third heat exchanger 23 can be controlled to be closed; when the load is less than or equal to a second preset value, the outdoor second heat exchanger 22 can be controlled to be closed, and the outdoor third heat exchanger 23 can be controlled to be opened, wherein the first preset value is more than or equal to the second preset value;

the other end of the outdoor second heat exchanger 22 is merged with the other end of the outdoor third heat exchanger 23 and then communicated to one end of the first throttling device 31 through the seventh pipeline 107, the other end of the first throttling device 31 is communicated to the fourth end 41a of the indoor first heat exchanger 41 through the eighth pipeline 108, and the fifth end 41b of the indoor first heat exchanger 41 is communicated to the suction end or the exhaust end of the compressor 10 through the ninth pipeline 109;

a thirteenth pipeline 113 and a fourteenth pipeline 114 are further included, one end of the thirteenth pipeline 113 is communicated with the fourth end 41a, the other end is communicated to the ninth pipeline 109, one end of the fourteenth pipeline 114 is communicated with the fifth end 41b, and the other end is communicated to the eighth pipeline 108.

The air conditioning system for the non-azeotropic refrigerant is provided with the gas-liquid separator, the outdoor second heat exchanger and the outdoor third heat exchanger, so that the refrigerant condensed by the outdoor first heat exchanger in a refrigeration mode enters the gas-liquid separator for gas-liquid separation, the separated gas low-boiling-point refrigerant can enter the outdoor second heat exchanger, the separated liquid high-boiling-point refrigerant can enter the outdoor third heat exchanger for heat exchange, the air conditioning system can select and control specific opening work of the outdoor second heat exchanger and the outdoor third heat exchanger according to the size of the load working condition, the outdoor second heat exchanger works when the load is large, the low-boiling-point refrigerant is adopted for evaporation heat exchange, the heat exchange effect can be increased in a refrigeration mode, the circulating low-boiling-point components in the system are excessive, the volume refrigerating capacity is large, and the refrigeration can be carried out under the condition of large load (such as high indoor temperature); when the load is small, the outdoor third heat exchanger works, the high-boiling-point refrigerant is adopted for evaporation and heat exchange, the circulating high-boiling-point components in the system are more, the volume refrigerating capacity is small, and the refrigeration can be carried out under the condition of small load (such as low indoor temperature); by adopting a component separation method, the capacity of a non-azeotropic working medium under different working conditions is adjusted, the energy efficiency of the system is improved, the operating range of the working conditions of the system is expanded, the efficient operation under different loads is realized, the capacity adjustment of the system is realized, the heat exchange efficiency can be improved, and the heat exchange performance of the evaporation and condensation heat exchange processes of the system is improved; the problems that the outdoor unit of the system is frosted under severe working conditions, and the comfort of the indoor environment is reduced when defrosting and defrosting are carried out can be solved; the reheating technology is adopted, so that the air supply temperature can be effectively increased, and the comfort of air supply is improved. This is disclosed sets up thirteenth pipeline and fourteenth pipeline through the business turn over, export at indoor first heat exchanger, thereby can make no matter under refrigeration, the working condition of heating through control, the homoenergetic makes the heat exchanger countercurrent exchange of indoor side, reduces the heat transfer difference in temperature, reduces heat transfer process's irreversible loss.

In some embodiments, a third control valve 73, a fourth control valve 74, a fifth control valve 75 and a sixth control valve 76 are further included, the third control valve 73 is disposed on a section between the eighth line 108 and the fourth end 41a, the fourth control valve 74 is disposed on the thirteenth line 113, the fifth control valve 75 is disposed on the fourteenth line 114, and the sixth control valve 76 is disposed on a section between the ninth line 109 and the fifth end 41 b. When in the cooling mode of operation, the third control valve 73 is controlled to be opened, the fourth control valve 74 is controlled to be closed, the fifth control valve 75 is controlled to be closed, and the sixth control valve 76 is controlled to be opened; when in the heating mode of operation, the third control valve 73 is controlled to be closed, the fourth control valve 74 is controlled to be opened, the fifth control valve 75 is controlled to be opened, and the sixth control valve 76 is controlled to be closed.

This disclosure sets up four control valves (third control valve 73, fourth control valve 74, fifth control valve 75 and sixth control valve 76) through the business turn over, the export at indoor first heat exchanger to no matter make under refrigeration, the working condition of heating, the homoenergetic makes the heat exchanger adverse current heat transfer of indoor side, reduces the heat transfer difference in temperature, reduces the irreversible loss of heat transfer process.

The method can achieve the purpose of adjusting the system capacity by changing the concentration ratio of the non-azeotropic mixed working medium by utilizing the different characteristics of the non-azeotropic working medium and the different refrigerant volume heating capacity.

Therefore, the present disclosure provides a novel air conditioning system based on the above two points, the system adopts a component separation technology, fully exerts the heat exchange characteristics of the non-azeotropic working medium, reduces the influence of heat transfer deterioration of the non-azeotropic working medium on the system, and simultaneously realizes the change of the operating component concentration of the refrigerant in the system through the switching of the valve, thereby changing the system capacity, adjusting the system load, widening the operating condition of the system, and enabling the system to operate near the optimal state point under different operating conditions.

The invention solves the following technical problems:

1. the problem that the running energy efficiency of a conventional mixed working medium air-conditioning system is too low is solved;

2. the problem of low heat exchange efficiency of a conventional mixed working medium circulating system is solved;

3. the problems that the deviation of the running condition of the compressor is large and the energy efficiency of the system is low are solved.

Has the advantages that: the technical effects of this application: the heat exchange characteristic of a non-azeotropic working medium is fully utilized, and the condensation side adopts a fractional condensation mode, so that the influence of non-condensable gas on the heat exchange process in the heat exchange process is reduced, and the heat exchange efficiency is improved; meanwhile, the adopted component separation method also reduces the influence of mass transfer resistance on the heat exchange process in the evaporation process. The concentration of refrigerant circulating components in the system is adjusted through switching the component separation device and the valve, and after high-efficiency operation under different loads is realized, the operation condition of the system is widened, so that the system can operate near an optimal state point under different loads. During heating operation, the temperature slippage characteristic of the non-azeotropic working medium is fully utilized, the defrosting and defrosting effects of the air conditioning unit under severe working conditions are remarkable, and the comfort of the indoor environment of the heating operation is improved.

In the condensation process, the high-boiling point refrigerant is first condensed, so that the proportion of the high-boiling point component in the gas phase is gradually reduced (the proportion of the low-boiling point component is increased), and the proportion of the high-boiling point component in the liquid phase is increased. Therefore, after condensing for a period of time, vapor-liquid separation is carried out, so that the separated liquid refrigerant is mainly high-boiling point working medium, and the separated gaseous refrigerant is mainly low-boiling point working medium.

The system can respectively operate the refrigerants with different components through component separation, and as mentioned above, the physical properties of the refrigerants are different, and the volumetric refrigerating capacities of the refrigerants are different. Therefore, under the same frequency, the system can have different operation capacities, and the frequency conversion technology of the compressor is combined, so that the operation range of the system is widened.

Such as: if the capacity and the load of the system need to be improved, the concentration of low boiling point components in the system can be increased by a component separation method, and the volume refrigerating capacity is increased; if the load of the system is to be reduced, the concentration of the high boiling point component in the system needs to be increased.

The improvement of this disclosure lies in:

the air conditioning system is applied to:

1. different from a conventional refrigeration system, the proposal adopts a non-azeotropic refrigerant;

2. by adopting a component separation method, the capacity of the system is adjusted, the heat exchange efficiency is improved, and the heat exchange performance of the evaporation and condensation heat exchange processes of the system is improved.

3. Through the switching of the valve, the non-azeotropic working medium capacity adjustment under different working conditions is realized, the energy efficiency of the system is improved, meanwhile, the operating range of the working conditions of the system is widened, and the high-efficiency operation under different loads is realized.

4. The problem of the system outdoor unit frosting under abominable operating mode, indoor environment travelling comfort descends when defrosting changes frost is solved.

5. And the reheating technology is adopted, so that the air supply temperature is increased, and the air supply comfort is improved.

The problem of defrosting and defrosting is solved by sacrificing a small part of heat exchange area. When in heating operation, 3 heat exchangers are arranged outdoors and are all used as evaporators. The non-azeotropic working medium has the temperature gradually increased during heat exchange in the evaporator due to the temperature slip characteristic, so that the evaporation temperature of the refrigerant in the auxiliary heat exchanger (the outdoor second heat exchanger and the outdoor third heat exchanger) is lower than the dew point temperature of the outdoor working condition, the outdoor second heat exchanger frosts, due to the temperature slip characteristic, the temperature of the refrigerant coming out of the outdoor second heat exchanger 22 is higher than the dew point temperature, then the refrigerant enters the outdoor first heat exchanger 21 for heat exchange, and the temperature of the refrigerant exchanging heat in the non-azeotropic working medium is higher than the dew point temperature and lower than the outdoor dry bulb temperature, so that the outdoor first heat exchanger cannot frost. When the frost layer of the outdoor second heat exchanger 22 is built up to a certain extent, the second control valve 72 is closed and the first control valve 71 is opened, so that the outdoor third heat exchanger 23 operates in place of the outdoor second heat exchanger 22. So as to realize frosting and defrosting in turn without stopping the machine.

In some embodiments, the first end 51a and the third end 51c are both located at the bottom of the gas-liquid separator 51, and the second end 51b is located above half the height of the gas-liquid separator 51 (the first end, the second end, and the third end are all ends of a pipeline). The first end is the inlet end of the gas-liquid separator in the refrigeration mode, and fluid (including gas-liquid two phases) condensed by the outdoor first heat exchanger can be effectively introduced through the bottom of the gas-liquid separator, so that the refrigerant can smoothly flow to the evaporator for evaporation in the heating process; the second end is a gas outlet end of the gas-liquid separator in the refrigeration mode, and the gas outlet end is arranged above the half height position of the gas-liquid separator and can lead out gas at the upper part of the gas separator so as to lead out the gas to the indoor second heat exchanger; the liquid outlet end of the gas-liquid separator can lead the liquid at the bottom of the gas-liquid separator to the indoor third heat exchanger when the third end is in a refrigeration mode, so that the gas and liquid after gas-liquid separation can be respectively led out, and low-boiling-point refrigerant heat exchange or high-boiling-point refrigerant heat exchange is realized according to different working condition loads, so that different refrigeration capacities are output, and the heat exchange efficiency is improved.

In some embodiments, one end of the outdoor first heat exchanger 21 is communicated to a discharge end or a suction end of the compressor 10 through a first pipeline 101, the other end is communicated to the first end 51a of the gas-liquid separator 51 through a second pipeline 102, the second end 51b of the gas-liquid separator 51 is communicated with one end of the outdoor second heat exchanger 22 through a third pipeline 103, and the third end 51c is communicated with one end of the outdoor third heat exchanger 23 through a fourth pipeline 104. The first pipeline can guide the compressor exhaust gas to the outdoor first heat exchanger 21 for condensation and heat release in the refrigeration mode, and can guide the refrigerant coming out of the outdoor first heat exchanger back to the air suction end of the compressor in the heating mode, and the second pipeline can conduct the outdoor first heat exchanger with the gas-liquid separator so as to guide the gas-liquid two-phase refrigerant condensed in the outdoor first heat exchanger to the gas-liquid separator for gas-liquid separation in the refrigeration mode; the third pipeline and the fourth pipeline are respectively used for leading out the gas outlet end of the gas separator to the indoor second heat exchanger and leading out the liquid outlet end of the gas separator to the indoor third heat exchanger, so that the gas and liquid after gas-liquid separation are respectively led out, low-boiling-point refrigerant heat exchange or high-boiling-point refrigerant heat exchange is realized according to different working condition loads, different refrigerating capacities are output, and the heat exchange efficiency is improved.

In some embodiments, the other end of the outdoor second heat exchanger 22 is connected to one end of a fifth pipeline 105, the other end of the outdoor third heat exchanger 23 is connected to one end of a sixth pipeline 106, the other end of the fifth pipeline 105 is merged with the other end of the sixth pipeline 106, the fifth pipeline 105 is provided with a first control valve 71, and the sixth pipeline 106 is provided with a second control valve 72;

when the load is larger than or equal to a first preset value, the first control valve 71 is opened by controlling the outdoor second heat exchanger 22 to be opened, and the second control valve 72 is closed by controlling the outdoor third heat exchanger 23 to be closed; when the load is less than or equal to a second preset value, the first control valve 71 is closed in the manner of controlling the outdoor second heat exchanger 22 to be closed, and the second control valve 72 is opened in the manner of controlling the outdoor third heat exchanger 23 to be opened.

The first control valve is arranged on a fifth pipeline communicated with the outdoor second heat exchanger, and the second control valve is arranged on a sixth pipeline communicated with the outdoor third heat exchanger, so that whether the outdoor second heat exchanger and the outdoor third heat exchanger are connected or not can be controlled respectively; when the load is large, the outdoor second heat exchanger works, the low-boiling-point refrigerant is adopted for evaporation and heat exchange, the heat exchange effect can be increased in a refrigeration mode, the circulating low-boiling-point components in the system are more, the volume refrigerating capacity is large, and the refrigeration can be carried out under the condition of large load (such as high indoor temperature); when the load is small, the outdoor third heat exchanger works, the high-boiling-point refrigerant is adopted for evaporation and heat exchange, the circulating high-boiling-point components in the system are more, the volume refrigerating capacity is small, and the refrigeration can be carried out under the condition of small load (such as low indoor temperature); by adopting a component separation method, the capacity of the non-azeotropic working medium under different working conditions is adjusted, the energy efficiency of the system is improved, meanwhile, the operating range of the working conditions of the system is widened, the high-efficiency operation under different loads is realized, the capacity of the system is adjusted, meanwhile, the heat exchange efficiency can be improved, and the heat exchange performance of the evaporation and condensation heat exchange processes of the system is improved.

In some embodiments, the air conditioner further comprises a first throttling device 31, a seventh pipeline 107, an eighth pipeline 108 and a ninth pipeline 109, the fifth pipeline 105 and the sixth pipeline 106 are merged and then communicated to one end of the first throttling device 31 through the seventh pipeline 107, the other end of the first throttling device 31 is communicated to one end of the indoor first heat exchanger 41 through the eighth pipeline 108, and the other end of the indoor first heat exchanger 41 is communicated to the suction end or the exhaust end of the compressor 10 through the ninth pipeline 109. This is the further preferred structural style of this disclosure, can carry out effectual switch-on with indoor first heat exchanger with outdoor second heat exchanger and outdoor third heat exchanger through seventh pipeline and eighth pipeline to can carry out the effect of throttle step-down to indoor outer refrigerant through first throttling arrangement, the ninth pipeline can be with indoor first heat exchanger and compressor switch-on, indoor first heat exchanger and compressor suction end intercommunication during the mode of refrigerating, indoor first heat exchanger and compressor discharge end switch-on during the mode of heating.

In some embodiments, further comprises a four-way valve 61, the four-way valve comprises an E-end E, S end S, C end C and a D-end D, the E-end E is communicated with the ninth pipeline 109, the S-end S is communicated with the suction end of the compressor 10, the C-end C is communicated with the first pipeline 101, the D-end D is communicated with the discharge end of the compressor 10, and the first communication state of the four-way valve is: the E end E is communicated with the S end S, the C end C is communicated with the D end D, at the moment, the indoor operation is in a refrigerating state, and the second communication state of the four-way valve is as follows: the E end E is communicated with the D end D, the S end S is communicated with the C end C, and at the moment, the indoor operation is in a heating state; the four-way valve 61 is switchable between the first communication state and the second communication state. This is a further preferred structural form of the present disclosure, and the indoor first heat exchanger, the outdoor first heat exchanger, and the compressor can be connected into an integrated system by the four-way valve, and can be switched to realize switching control between the cooling mode and the heating mode.

In some embodiments, the system further comprises a tenth pipeline 110 and an indoor second heat exchanger 42, wherein one end of the tenth pipeline 110 is communicated with the first pipeline 101 and penetrates into the gas-liquid separator 51 for heat exchange, and the other end is communicated to one end of the indoor second heat exchanger 42. This openly still through the setting of tenth pipeline and indoor second heat exchanger, can draw high temperature high pressure refrigerant in order to get into the gas-liquid separation in the gas branch and heat in the gas branch from the compressor exhaust under the refrigeration mode to improve gas-liquid separation's effect, and reach the tenth pipeline after the heat transfer to indoor second heat exchanger in, can carry out reheat effect to the indoor air after the indoor first heat exchanger refrigeration, in order to improve the comfort level of indoor air.

The main embodiment, as shown in fig. 1 to 4, in some embodiments, further includes an eleventh pipeline 111 and a second throttling device 32, the other end of the indoor second heat exchanger 42 is connected to the eighth pipeline 108 through the eleventh pipeline 111, and the second throttling device 32 is disposed on the eleventh pipeline 111. The structure in the main embodiment of the present disclosure is that the other end of the indoor second heat exchanger is connected to the eighth pipeline, that is, the position between the first throttling device and the indoor first heat exchanger (merging action), and after merging, the indoor second heat exchanger enters the indoor first heat exchanger to evaporate and absorb heat, and finally returns to the air suction end of the compressor together.

5-8, the first alternative embodiment further includes an eleventh pipeline 111, a second throttling device 32, an indoor third heat exchanger 43 and a twelfth pipeline 112, the other end of the indoor second heat exchanger 42 is communicated to one end of the indoor third heat exchanger 43 through the eleventh pipeline 111, the eleventh pipeline 111 is provided with the second throttling device 32, and the other end of the indoor third heat exchanger 43 is communicated to the ninth pipeline 109 through the twelfth pipeline 112. The structure in the first alternative embodiment of the present disclosure is that the other end of the indoor second heat exchanger is connected to the second throttling device and the indoor third heat exchanger, so as to evaporate and absorb heat in the indoor third heat exchanger, join with the refrigerant after evaporating and absorbing heat from the indoor first heat exchanger, and finally return to the suction end of the compressor together. Can improve like this to indoor refrigeration evaporation heat transfer effect, realize refrigerating step by step, control as required, improve the comfort level to finally through reheat in order to improve the comfort level, realize the effect of intelligence refrigeration cooling.

An indoor third heat exchanger 43 is added behind the second throttling device, so that the refrigerant coming out of the second throttling device 32 is mixed with the refrigerant coming out of the indoor first heat exchanger 41 after heat exchange is completed in the indoor third heat exchanger 43, and the mixed refrigerant enters the suction port of the compressor through a four-way valve 61, thereby completing the whole cycle: other operating conditions and valve switching are consistent with the main embodiment.

In some embodiments, the portion of the pipe segment that the tenth pipe 110 penetrates into the gas-liquid separator 51 is not in communication with the fluid seal inside the gas-liquid separator 51; and/or, a part of the pipe section of the tenth pipe 110 penetrating into the gas-liquid separator 51 is a serpentine pipe section. This is this the preferred structural style of this disclosure's tenth pipeline, and it does not take place to leak in getting into the gas branch, only carries out the heat transfer effect, guarantees not to influence the heat transfer performance of the refrigerant in the gas branch, and snakelike bend section can increase heat transfer area, improves heat transfer effect.

In some embodiments, a first fan 81 is further included, and the first fan 81 can drive the indoor air flow to flow through the indoor first heat exchanger 41 and then flow through the indoor second heat exchanger 42, that is, the indoor second heat exchanger 42 is located at the downstream side of the indoor first heat exchanger 41 along the air flow direction. This is openly through the setting of first fan to indoor second heat exchanger sets up in the downstream side of the air current flow direction of indoor first heat exchanger, can make the room air earlier through indoor first heat exchanger refrigeration cooling, and the effect of reheating through indoor second heat exchanger can improve the comfort level of room air.

In some embodiments, when an indoor third heat exchanger 43 is further included, the first fan 81 can drive the indoor air flow to pass through the indoor first heat exchanger 41, the indoor third heat exchanger 43, and the indoor second heat exchanger 42 in sequence. This is the preferred structural style of this first alternative embodiment of this disclosure, still is provided with indoor third heat exchanger between indoor first heat exchanger and indoor second heat exchanger, can realize the process of cooling down and rising temperature step by step to the room air to control as required, improve indoor comfort level.

In some embodiments, a second fan 82 is also included:

the second fan 82 can drive the outdoor air flow to flow through the outdoor second heat exchanger 22 first and then flow through the outdoor first heat exchanger 21, that is, the outdoor first heat exchanger 21 is located on the downstream side of the outdoor second heat exchanger 22 along the air flow direction; and/or the second fan 82 can drive the outdoor air flow to firstly flow through the outdoor third heat exchanger 23 and then flow through the outdoor first heat exchanger 21, that is, the outdoor first heat exchanger 21 is located on the downstream side of the outdoor third heat exchanger 23 in the air flow direction. According to the outdoor heat exchanger, the second fan is arranged, the outdoor second heat exchanger is arranged on the upstream side of the airflow flowing direction of the outdoor first heat exchanger, so that indoor air can exchange heat through the outdoor second heat exchanger firstly and then through the outdoor first heat exchanger, and the temperature of the outdoor first heat exchanger is higher than that of the outdoor second heat exchanger, so that heat exchange of small temperature difference gradual temperature rise can be realized, and the heat exchange effect is improved; the outdoor third heat exchanger is arranged on the upstream side of the airflow flowing direction of the outdoor first heat exchanger, so that indoor air can exchange heat through the outdoor third heat exchanger firstly and then exchange heat through the outdoor first heat exchanger, and the heat exchange of small temperature difference gradual temperature rise can be realized due to the fact that the temperature of the outdoor first heat exchanger is higher than that of the outdoor third heat exchanger, and the heat exchange effect is improved.

In some embodiments, the outdoor second heat exchanger 22 and the outdoor third heat exchanger 23 are located in parallel along the airflow flowing direction, that is, the outdoor second heat exchanger 22 and the outdoor third heat exchanger 23 are located in a cross section perpendicular to the airflow flowing direction. The outdoor second heat exchanger and the outdoor third heat exchanger are in parallel positions in the airflow flowing direction, namely the outdoor second heat exchanger and the outdoor third heat exchanger are not distinguished by priority, and airflow can simultaneously flow through the outdoor second heat exchanger and the outdoor third heat exchanger to perform heat exchange.

The present disclosure also provides a method of controlling a variable load adjustment air conditioning system as set forth in any of the preceding claims, comprising:

a control step, when the air conditioner is operated in a cooling mode: when the load is greater than or equal to a first preset value, the outdoor second heat exchanger 22 is controlled to be opened, and the outdoor third heat exchanger 23 is controlled to be closed; when the load is less than or equal to a second preset value, the outdoor second heat exchanger 22 is controlled to be closed, and the outdoor third heat exchanger 23 is controlled to be opened; when the load is smaller than the second preset value and smaller than the first preset value, the outdoor second heat exchanger 22 is controlled to be opened, and the outdoor third heat exchanger 23 is controlled to be opened; wherein the first preset value is more than or equal to the second preset value.

The air conditioning system shown in fig. 1 includes a compressor 10, an outdoor first heat exchanger 21, an outdoor second heat exchanger 22, an outdoor third heat exchanger 23, a first throttle device 31, a second throttle device 32, an indoor first heat exchanger 41, an indoor second heat exchanger 42, a gas-liquid separator 51, a first control valve 71, a second control valve 72, a first fan 81, a second fan 82, and the like.

The system circularly adopts non-azeotropic refrigerants, and the standard boiling points of the non-azeotropic refrigerants have certain difference, so that the non-azeotropic refrigerants can have different heat exchange characteristics from pure working media (or near-azeotropic working media) in the heat exchange process. In the evaporation process, the low boiling point working medium is firstly evaporated, so that the low boiling point working medium components in the gaseous refrigerant are continuously increased, and the concentration of the high boiling point components in the liquid refrigerant is gradually increased. Similarly, during the condensation process, the high boiling point component is condensed first, the concentration of the high boiling point component in the gaseous refrigerant is gradually reduced, and the concentration of the high boiling point component in the liquid refrigerant is gradually increased. Therefore, the system cycle makes full use of the above characteristics of the non-azeotropic working medium, and combines the component separation technology to provide a new system cycle, and the specific implementation mode is as follows:

in some embodiments, when further comprising a first control valve 71 and a second control valve 72:

in the control step, when the load is larger than or equal to a first preset value, the first control valve 71 is opened, and the second control valve 72 is closed; when the load is less than or equal to a second preset value, closing the first control valve 71 and opening the second control valve 72; when the second preset value < load < first preset value, the first control valve 71 is opened, and the second control valve 72 is opened.

1. In the refrigeration mode of fig. 1, the adjustment of the system load is realized by switching the valves. Generally, the volume refrigerating capacity of the low boiling point is large, the volume refrigerating capacity of the high boiling point is small, the component concentrations of refrigerant with high boiling point and low boiling point in the system are adjusted under the same compressor displacement and frequency, the adjustment of system load is achieved, meanwhile, the non-azeotropic capacity adjusting characteristic is coupled with the compressor frequency conversion technology, the system capacity adjustment under wider working conditions is achieved, therefore, the system can run near the optimal state point under different working conditions, meanwhile, in order to fully utilize the temperature slippage characteristic of the non-azeotropic working medium, the indoor first heat exchanger 41 is suitable for selecting and using multiple rows of heat exchangers, and other heat exchangers are similar. The specific implementation mode is as follows:

a. under the refrigeration working condition, when the load is large, the concentration of the high-pressure component (low boiling point) is increased, at the moment, the second control valve 72 is closed, and the first control valve 71 is opened.

The high-temperature and high-pressure refrigerant discharged from the compressor 10 is divided into two paths, one path enters the outdoor first heat exchanger 21, is condensed into a vapor-liquid two-phase state, and then enters the gas-liquid separator 51 (a mixed refrigerant with a certain volume is stored in the gas-liquid separator), at this time, the liquid phase in the gas-liquid separator is mainly a low-pressure component (high boiling point), and the gas phase is mainly a high-pressure component (low boiling point). As the first control valve 71 (preferably, two-way valve) is opened and the second control valve 72 (preferably, two-way valve) is closed, the gaseous refrigerant with the high-pressure component (low-boiling point) component being abundant enters the outdoor second heat exchanger 22 to be condensed into a liquid state, and then is throttled and depressurized through the first throttling means 31; and the other path of refrigerant from the compressor enters the built-in spiral coil in the gas-liquid separator 51 to heat the liquid refrigerant in the gas-liquid separator, so that the low-boiling point refrigerant in the liquid refrigerant is volatilized, and the separation purity is improved. The refrigerant that comes out from spiral coil gets into indoor second heat exchanger 42 heat transfer, improves indoor air supply temperature, improves air supply travelling comfort, after second throttling arrangement 32 throttle step-down afterwards, mixes with the main road refrigerant that comes out from first throttling arrangement 31, and the refrigerant after the mixture gets into indoor first heat exchanger 41 heat transfer, then gets into the induction port of compressor through four-way valve 61, is discharged after the completion of the compression to accomplish whole refrigeration cycle. In this mode, the number of circulating low-boiling components in the system is large, the volume refrigerating capacity is large, and the load is large.

b. In the refrigeration condition, when the load is small, the concentration of the low-pressure component (high boiling point) is increased, and at this time, the second control valve 72 is opened and the first control valve 71 is closed.

The high-temperature and high-pressure refrigerant discharged from the compressor 10 is divided into two paths, one of which enters the outdoor first heat exchanger 21, is condensed into a gas-liquid two-phase state, and then enters the gas-liquid separator 51 (where a certain amount of refrigerant is stored), where the liquid phase is mainly low-pressure (high-boiling point) refrigerant and the vapor phase is mainly high-pressure (low-boiling point) refrigerant. As the second control valve 72 is opened, the first control valve 71 is closed, and the liquid refrigerant mainly containing low-pressure (high-boiling point) components enters the outdoor third heat exchanger 23 to be further subcooled, and then is throttled and depressurized by the first throttling device 31; the other path of refrigerant from the compressor enters the built-in spiral coil in the gas-liquid separator 51, and heats the liquid refrigerant in the gas-liquid separator to volatilize high-pressure components (low boiling point) in the liquid refrigerant, thereby increasing the concentration of high-boiling point components in the liquid refrigerant in the gas-liquid separator. The refrigerant coming out of the spiral coil enters the indoor second heat exchanger 42 for heat exchange, then is throttled and depressurized by the second throttling device 32, is mixed with the refrigerant mainly with a high boiling point coming out of the first throttling device 31, then enters the indoor first heat exchanger 41 for heat exchange, passes through the four-way valve 61 after heat exchange is completed, enters an air suction port of the compressor, is discharged after compression is completed, and accordingly the whole refrigeration cycle is completed. In this mode, the high boiling point components circulating in the system are more, the volume refrigerating capacity is smaller, and the load is smaller.

c. Under the refrigeration working condition, when the compressor operates in a normal proportion, the first control valve 71 and the second control valve 72 are both opened.

High-temperature and high-pressure refrigerant gas discharged by the compressor 10 is divided into two paths, one path of the high-temperature and high-pressure refrigerant gas directly enters the outdoor first heat exchanger 21 for heat exchange, the high-temperature and high-pressure refrigerant gas is condensed into a gas-liquid two-phase state and then enters the gas-liquid separator 51, the liquid phase in the gas-liquid separator is mainly low-pressure components (high boiling point), the gas phase is mainly high-pressure components (low boiling point), and the refrigerant with a large proportion of gaseous high-pressure components (low boiling point) enters the outdoor second heat exchanger 22 for heat exchange and is condensed into a liquid state; the refrigerant with a large liquid low-pressure component (high boiling point) ratio enters the outdoor third heat exchanger 23 to be further subcooled, then the two paths of refrigerants are mixed, and the throttling and pressure reduction are carried out through the first throttling device 31; and the other path of refrigerant discharged from the compressor enters a spiral coil arranged in the gas-liquid separator 51, the liquid refrigerant in the gas-liquid separator 51 is heated to improve the separation purity, then the refrigerant sequentially passes through the indoor second heat exchanger 42 and the second throttling device 32 and is finally mixed with the refrigerant discharged from the first throttling device 31, the mixed refrigerant enters the indoor first heat exchanger 41 for heat exchange, enters an air suction port of the compressor through the four-way valve 61 after the heat exchange is finished, is compressed and discharged, and the whole refrigeration cycle is finished.

In some embodiments, the detecting step can also detect the outdoor ambient temperature T;

the judging step is to judge the relation between the T outside and a third preset temperature and judge whether the heating working condition is met;

the control step comprises the following steps of: when the third preset temperature is not less than T and not more than the fourth preset temperature, controlling the outdoor second heat exchanger 22 and the outdoor third heat exchanger 23 to be communicated; and when Tout is less than a third preset temperature, controlling the outdoor second heat exchanger 22 and the outdoor third heat exchanger 23 to be alternately communicated.

in the control step, when the third preset temperature is not more than T and not more than the fourth preset temperature, the first control valve 71 and the second control valve 72 are both controlled to be opened; and when Tout < the third preset temperature, controlling the first control valve 71 and the second control valve 72 to be opened alternately.

2. When the heating working condition is operated (figure 2), the system can realize alternate defrosting and defrosting of the outdoor heat exchanger through switching of the valve without stopping, thereby ensuring normal indoor heating. Meanwhile, the temperature slippage characteristic of the non-azeotropic working medium is fully utilized, because the non-azeotropic working medium gradually slips to the dew point temperature from the bubble point temperature in the heat exchange process in the evaporator, the temperature is gradually increased, and the slippage temperature of the non-azeotropic working medium is higher, the phenomenon is more obvious. Therefore, in the cold and dry season in the north, the dry bulb temperature and the dew point temperature of the outdoor air are different greatly, and the system can give full advantage. By the control program, during heating operation, the evaporating temperature of the outdoor second heat exchanger 22 and the outdoor third heat exchanger 23 is lower than the dew-point temperature of the outdoor environment, and the evaporating temperature of the outdoor first heat exchanger 22 is higher than the dew-point temperature of the outdoor environment but lower than the dry bulb temperature of the outdoor environment. Therefore, when the outdoor first heat exchanger 21 is operated in a severe working condition and a refrigerating mode, frosting can not occur, frosting can only occur on the outdoor second heat exchanger 22 and the outdoor third heat exchanger 23, and then heating operation and defrosting are carried out simultaneously through switching of the valves, and continuity and stability of system operation and comfort of a heating environment are improved. The specific operation mode is as follows:

a. in the heating operation under the common working condition (the outdoor heat exchanger does not frost), the first control valve 71 and the second control valve 72 are both opened, and the second throttling device 32 is closed;

at this time, the high-temperature and high-pressure exhaust gas of the compressor enters the indoor first heat exchanger 41 through the four-way valve 61, exchanges heat with indoor air, is condensed into liquid after exchanging heat, then enters the outdoor second heat exchanger 22 and the outdoor third heat exchanger 23 respectively after being throttled and depressurized by the first throttling device 31 to exchange heat, absorbs heat of an outdoor environment, then enters the outdoor first heat exchanger 21 after passing through the gas-liquid separator 51 (the gas-liquid separator 51 is equivalent to a liquid storage tank), enters an air suction port of the compressor through the four-way valve after completing heat exchange, is compressed and discharged, and accordingly the whole heating cycle is completed.

b. When the outdoor heat exchanger is operated under a severe working condition (frosting occurs), the first control valve 71 and the second control valve 72 are opened in turn, and only one valve is opened and the second throttling device 32 is closed during operation.

At this time, the high-temperature and high-pressure exhaust gas of the compressor is subjected to heat exchange by the indoor first heat exchanger 41, and then is throttled and depressurized by the first throttling device 31. At this time, the first control valve 71 is opened and the second control valve 72 is closed. At this time, because the environment temperature of the outdoor side is lower, the evaporation temperature is also lower and is lower than the dew point temperature of the outdoor environment, the outdoor heat exchanger is easy to frost, the refrigerant frosts after heat exchange through the outdoor second heat exchanger 22, but the non-azeotropic working medium has the temperature slip characteristic, the temperature of the refrigerant after heat exchange in the outdoor second heat exchanger 22 is increased, and through the early-stage system matching and control, the temperature of the refrigerant coming out of the outdoor second heat exchanger 22 is increased and is higher than the dew point temperature of the outdoor environment but is lower than the dry bulb temperature of the outdoor environment; then, the refrigerant passes through the gas-liquid separator 51 (which only corresponds to one liquid storage tank), enters the outdoor first heat exchanger 21 for heat exchange, enters the suction port of the compressor through the four-way valve 61 after the heat exchanger is finished, is compressed and discharged, and then the whole heating cycle is finished. As the system is continuously operated, frost on the outdoor second heat exchanger 22 becomes thicker and thicker, and heat exchange becomes worse. At this time, the first control valve 71 is closed, the second control valve 72 is opened, and the outdoor third heat exchanger 23 is operated in place of the outdoor second heat exchanger 22, and the system operation is performed in the same manner as described above. At this time, the outdoor second heat exchanger 22 is subjected to defrosting treatment. When the defrosting treatment of the outdoor second heat exchanger 22 is completed and the frosting heat exchange of the outdoor third heat exchanger 23 is poor, the control valves are switched, so that the first control valve 71 is opened and the second control valve 72 is closed, and the process is repeated in this way, and only one outdoor second heat exchanger 22 and one outdoor third heat exchanger 23 in the system participate in circulation each time, so that the system does not stop during heating operation and continuously defrosts and defrosts. And the stability of the system operation is ensured.

In conclusion, the system innovatively applies the non-azeotropic refrigerant to the cooling and heating unit, and fully utilizes the capacity regulating property (refrigeration) and the temperature slip property of the non-azeotropic working medium. The system can run efficiently and stably under different working conditions.

During refrigeration operation, the capacity of the non-azeotropic working medium is coupled with the frequency conversion technology of the compressor, so that the system can efficiently operate under a wider working condition. The condensation side adopts a component separation mode, and the change of the operation concentration component of the refrigerant in the system (the change of the concentration component of the refrigerant in the system and the corresponding change of the volume refrigerating capacity) is realized by switching the valve, so that the adjustment of the system capacity is realized. Through the component separation mode of adoption, alleviate the heat transfer "aggravation" effect of refrigerant in the heat transfer process, promote the heat exchange efficiency of system. Meanwhile, a spiral coil is arranged in the gas-liquid separator 51, and high-temperature exhaust gas is used for heating liquid in the gas-liquid separator, so that low-boiling-point working media in a liquid phase are volatilized, and the separation purity is improved. The indoor second heat exchanger 42 heats the cooled and dehumidified air, so that the temperature of the outlet air is not too low, and the comfort of the indoor environment temperature is improved.

When the heat exchanger is used for heating, the temperature slip characteristic of the non-azeotropic working medium is fully utilized, a small part of the area of the outdoor heat exchanger is sacrificed, and the frosting prevention of the main body of the heat exchanger is ensured. Therefore, the system can run stably and continuously, the machine does not need to be stopped when heating and defrosting are carried out, and the comfort of the indoor environment is ensured.

In some embodiments, when third control valve 73, fourth control valve 74, fifth control valve 75, and sixth control valve 76 are included,

the control step, when in the cooling mode, controls the third control valve 73 to be opened, the fourth control valve 74 to be closed, the fifth control valve 75 to be closed and the sixth control valve 76 to be opened; when in the heating mode of operation, the third control valve 73 is controlled to be closed, the fourth control valve 74 is controlled to be opened, the fifth control valve 75 is controlled to be opened, and the sixth control valve 76 is controlled to be closed.

The above description is only exemplary of the present disclosure and should not be taken as limiting the disclosure, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure. The foregoing is only a preferred embodiment of the present disclosure, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present disclosure, and these modifications and variations should also be regarded as the protection scope of the present disclosure.

Claims

1. A variable load air conditioning system is characterized in that: the method comprises the following steps:

the air-conditioning system comprises a compressor (10), an outdoor first heat exchanger (21), an outdoor second heat exchanger (22), an outdoor third heat exchanger (23), an indoor first heat exchanger (41) and a gas-liquid separator (51), wherein the gas-liquid separator (51) comprises a first end (51a), a second end (51b) and a third end (51c), the air-conditioning system comprises a first boiling point refrigerant and a second boiling point refrigerant, the boiling point of the first boiling point refrigerant is less than that of the second boiling point refrigerant, one end of the outdoor first heat exchanger (21) can be communicated to a gas discharge end or a gas suction end of the compressor (10), and the other end of the outdoor first heat exchanger can be communicated to the first end (51a) of the gas-liquid separator (51);

the second end (51b) is a gas end, the gas separated in the gas-liquid separator (51) can be communicated with one end of the outdoor second heat exchanger (22) through the second end (51b), the third end (51c) is a liquid end, and the liquid separated in the gas-liquid separator (51) can be communicated with one end of the outdoor third heat exchanger (23) through the third end (51 c);

the other end of the outdoor second heat exchanger (22) and the other end of the outdoor third heat exchanger (23) can be communicated with the fourth end (41a) of the indoor first heat exchanger (41) after being mixed, and the fifth end (41b) of the indoor first heat exchanger (41) can be communicated to the suction end or the exhaust end of the compressor (10);

when the load is larger than or equal to a first preset value, the outdoor second heat exchanger (22) can be controlled to be opened, and the outdoor third heat exchanger (23) can be controlled to be closed; when the load is less than or equal to a second preset value, the outdoor second heat exchanger (22) can be controlled to be closed, the outdoor third heat exchanger (23) can be controlled to be opened, and the first preset value is greater than or equal to the second preset value;

the other end of the outdoor second heat exchanger (22) is converged with the other end of the outdoor third heat exchanger (23) and then communicated to one end of the first throttling device (31) through a seventh pipeline (107), the other end of the first throttling device (31) is communicated to a fourth end (41a) of the indoor first heat exchanger (41) through an eighth pipeline (108), and a fifth end (41b) of the indoor first heat exchanger (41) is communicated to a suction end or a discharge end of the compressor (10) through a ninth pipeline (109);

the device also comprises a thirteenth pipeline (113) and a fourteenth pipeline (114), one end of the thirteenth pipeline (113) is communicated with the fourth end (41a), the other end of the thirteenth pipeline is communicated to the ninth pipeline (109), one end of the fourteenth pipeline (114) is communicated with the fifth end (41b), and the other end of the fourteenth pipeline is communicated to the eighth pipeline (108).

2. The variable load modulating air conditioning system of claim 1 wherein:

the pipeline joint is characterized by further comprising a third control valve (73), a fourth control valve (74), a fifth control valve (75) and a sixth control valve (76), wherein the third control valve (73) is arranged on a pipeline section between the eighth pipeline (108) and the fourth end (41a), the fourth control valve (74) is arranged on a thirteenth pipeline (113), the fifth control valve (75) is arranged on a fourteenth pipeline (114), and the sixth control valve (76) is arranged on a pipeline section between the ninth pipeline (109) and the fifth end (41 b).

3. The variable load modulating air conditioning system of claim 1 wherein:

the first end (51a) and the third end (51c) are both located at the bottom of the gas-liquid separator (51), and the second end (51b) is located above half the height of the gas-liquid separator (51).

4. The variable load modulating air conditioning system of claim 1 wherein:

one end of the outdoor first heat exchanger (21) is communicated to a discharge end or a suction end of the compressor (10) through a first pipeline (101), the other end of the outdoor first heat exchanger is communicated to the first end (51a) of the gas-liquid separator (51) through a second pipeline (102), the second end (51b) of the gas-liquid separator (51) is communicated with one end of the outdoor second heat exchanger (22) through a third pipeline (103), and the third end (51c) is communicated with one end of the outdoor third heat exchanger (23) through a fourth pipeline (104).

5. The variable load regulated air conditioning system of claim 4, wherein:

the other end of the outdoor second heat exchanger (22) is communicated to one end of a fifth pipeline (105), the other end of the outdoor third heat exchanger (23) is communicated to one end of a sixth pipeline (106), the other end of the fifth pipeline (105) is converged with the other end of the sixth pipeline (106), a first control valve (71) is arranged on the fifth pipeline (105), and a second control valve (72) is arranged on the sixth pipeline (106);

when the load is larger than or equal to a first preset value, the first control valve (71) is opened in the mode that the outdoor second heat exchanger (22) is controlled to be opened, and the second control valve (72) is closed in the mode that the outdoor third heat exchanger (23) is controlled to be closed; when the load is less than or equal to a second preset value, the mode that the outdoor second heat exchanger (22) is controlled to be closed is to close the first control valve (71), and the mode that the outdoor third heat exchanger (23) is controlled to be opened is to open the second control valve (72).

6. The variable load regulated air conditioning system of claim 5, wherein:

the four-way valve further comprises a four-way valve (61), the four-way valve comprises an E end (E), an S end (S), a C end (C) and a D end (D), the E end (E) is communicated with the ninth pipeline (109), the S end (S) is communicated with the air suction end of the compressor (10), the C end (C) is communicated with the first pipeline (101), the D end (D) is communicated with the air exhaust end of the compressor (10), and the first communication state of the four-way valve is as follows: the E end (E) is communicated with the S end (S), the C end (C) is communicated with the D end (D), at the moment, the indoor operation is in a refrigerating state, and the second communication state of the four-way valve is as follows: the end E is communicated with the end D, the end S is communicated with the end C, and the indoor operation is in a heating state; the four-way valve (61) can be switched between the first communication state and the second communication state.

7. The variable load regulated air conditioning system of claim 6, wherein:

the heat exchanger further comprises a tenth pipeline (110) and an indoor second heat exchanger (42), wherein one end of the tenth pipeline (110) is communicated with the first pipeline (101) and then penetrates into the gas-liquid separator (51) for heat exchange, and the other end of the tenth pipeline is communicated to one end of the indoor second heat exchanger (42).

8. The variable load modulated air conditioning system of claim 7, wherein:

the other end of the indoor second heat exchanger (42) is communicated to the eighth pipeline (108) through the eleventh pipeline (111), and the eleventh pipeline (111) is provided with a second throttling device (32);

or the heat exchanger further comprises an eleventh pipeline (111), a second throttling device (32), an indoor third heat exchanger (43) and a twelfth pipeline (112), the other end of the indoor second heat exchanger (42) is communicated to one end of the indoor third heat exchanger (43) through the eleventh pipeline (111), the eleventh pipeline (111) is provided with the second throttling device (32), and the other end of the indoor third heat exchanger (43) is communicated to the ninth pipeline (109) through the twelfth pipeline (112).

9. The variable load regulated air conditioning system according to claim 8, wherein:

the part of the pipe section of the tenth pipeline (110) penetrating into the gas-liquid separator (51) is not communicated with the fluid seal inside the gas-liquid separator (51); and/or the part of the pipe section, penetrating into the gas-liquid separator (51), of the tenth pipeline (110) is a serpentine pipe bending section.

10. A variable load modulating air conditioning system as claimed in any one of claims 7 to 9 wherein:

the air conditioner further comprises a first fan (81), wherein the first fan (81) can drive the indoor air flow to firstly flow through the indoor first heat exchanger (41) and then flow through the indoor second heat exchanger (42), namely the indoor second heat exchanger (42) is positioned on the downstream side of the indoor first heat exchanger (41) along the air flow direction.

11. The variable load regulated air conditioning system according to claim 10, wherein:

when the indoor heat exchanger (43) is further included, the first fan (81) can drive indoor air flow to sequentially pass through the indoor first heat exchanger (41), the indoor third heat exchanger (43) and the indoor second heat exchanger (42).

12. A variable load modulating air conditioning system as claimed in any one of claims 1 to 11 wherein:

further comprising a second fan (82):

the second fan (82) can drive outdoor airflow to firstly flow through the outdoor second heat exchanger (22) and then flow through the outdoor first heat exchanger (21), namely the outdoor first heat exchanger (21) is positioned on the downstream side of the outdoor second heat exchanger (22) along the airflow flowing direction; and/or the second fan (82) can drive the outdoor air flow to firstly flow through the outdoor third heat exchanger (23) and then flow through the outdoor first heat exchanger (21), namely the outdoor first heat exchanger (21) is positioned on the downstream side of the outdoor third heat exchanger (23) along the air flow direction.

13. A variable load modulating air conditioning system as claimed in claim 12, wherein:

the outdoor second heat exchanger (22) and the outdoor third heat exchanger (23) are located in parallel along the airflow flowing direction, namely, the outdoor second heat exchanger (22) and the outdoor third heat exchanger (23) are located in a cross section perpendicular to the airflow flowing direction.

14. A control method of a variable load adjustment air conditioning system according to any one of claims 1 to 13, characterized by: the method comprises the following steps:

a control step, when the air conditioner is operated in a cooling mode: when the load is larger than or equal to a first preset value, the outdoor second heat exchanger (22) is controlled to be opened, and the outdoor third heat exchanger (23) is controlled to be closed; when the load is less than or equal to a second preset value, the outdoor second heat exchanger (22) is controlled to be closed, and the outdoor third heat exchanger (23) is controlled to be opened; when the load is smaller than the second preset value and smaller than the first preset value, the outdoor second heat exchanger (22) is controlled to be opened, and the outdoor third heat exchanger (23) is controlled to be opened; wherein the first preset value is more than or equal to the second preset value.

15. The control method according to claim 14, characterized in that:

when further comprising a first control valve (71) and a second control valve (72):

in the control step, when the load is larger than or equal to a first preset value, the first control valve (71) is opened, and the second control valve (72) is closed; when the load is less than or equal to a second preset value, closing the first control valve (71) and opening the second control valve (72); -opening said first control valve (71), and-opening said second control valve (72), when the second preset value < load < first preset value.

16. The control method according to claim 14, characterized in that:

the detecting step can also detect the outdoor ambient temperature T_{Outer cover}；

the control step comprises the following steps of: when the third preset temperature is less than or equal to T_{Outer cover}When the temperature is less than or equal to a fourth preset temperature, controlling the outdoor second heat exchanger (22) and the outdoor third heat exchanger (23) to be communicated; when T is_{Outer cover}When the temperature is lower than a third preset temperature, controlling the outdoor second heat exchanger (22) and the outdoor third heat exchanger (23) to be alternately communicated; wherein the third preset temperature is less than the fourth preset temperature.

17. The control method according to claim 16, characterized in that:

in the control step, when the third preset temperature is less than or equal to T_{Outer cover}When the temperature is less than or equal to a fourth preset temperature, controlling the first control valve (71) and the second control valve (72) to be opened; when T is_{Outer cover}And when the temperature is lower than a third preset temperature, controlling the first control valve (71) and the second control valve (72) to be opened alternately.

18. The control method according to claim 14, characterized in that:

when the third control valve (73), the fourth control valve (74), the fifth control valve (75) and the sixth control valve (76) are included,

the control step is that when the refrigeration mode is operated, the third control valve (73) is controlled to be opened, the fourth control valve (74) is controlled to be closed, the fifth control valve (75) is controlled to be closed, and the sixth control valve (76) is controlled to be opened; when the heating mode is operated, the third control valve (73) is controlled to be closed, the fourth control valve (74) is controlled to be opened, the fifth control valve (75) is controlled to be opened, and the sixth control valve (76) is controlled to be closed.