阅读说明：本技术 一种空调系统及其控制方法 (Air conditioning system and control method thereof ) 是由 赵桓 梁尤轩 钟权 黄宇杰 于 2021-09-17 设计创作，主要内容包括：本发明公开了一种空调系统及其控制方法,该装置包括：压缩机(1)、室外换热器(61)和室内换热器(63)；压缩机(1)、室外换热器(61)和室内换热器(63)之间,通过管路连通；换热系统采用CO-(2)作为制冷剂；在换热系统中,在室外换热器(61)的第一端口和室内换热器(63)的第一端口之间的管路中设置有膨胀机(43)；在室外换热器(61)的第二端口与压缩机(1)之间的管路中设置有第一四通阀(51),在室外换热器(61)的第一端口与膨胀机(43)之间,设置有第二四通阀(52)。该方案,通过在空调系统采用CO-(2)作为制冷剂时,采用膨胀机节流,能够提高高温制冷时的能效比。(The invention discloses an air conditioning system and a control method thereof, wherein the device comprises: a compressor (1), an outdoor heat exchanger (61) and an indoor heat exchanger (63); the compressor (1), the outdoor heat exchanger (61) and the indoor heat exchanger (63) are communicated through pipelines; the heat exchange system adopts CO 2 As a refrigerant; in the heat exchange system, an expander (43) is arranged in a pipeline between a first port of the outdoor heat exchanger (61) and a first port of the indoor heat exchanger (63); a first four-way valve (51) is provided in a pipeline between the second port of the outdoor heat exchanger (61) and the compressor (1), and a second four-way valve (52) is provided between the first port of the outdoor heat exchanger (61) and the expander (43). The scheme adopts CO in the air conditioning system 2 When the refrigerant is used, the energy efficiency ratio during high-temperature refrigeration can be improved by throttling the refrigerant with an expander.)

1. An air conditioning system, comprising: a compressor (1), an outdoor heat exchanger (61) and an indoor heat exchanger (63); the compressor (1), the outdoor heat exchanger (61) and the indoor heat exchanger (63) are communicated through pipelines; the air conditioning system adopts CO₂As a refrigerant;

in the air conditioning system, an expander (43) is provided in a piping between a first port of the outdoor heat exchanger (61) and a first port of the indoor heat exchanger (63);

a first four-way valve (51) is provided in a pipeline between the second port of the outdoor heat exchanger (61) and the compressor (1), and a second four-way valve (52) is provided between the first port of the outdoor heat exchanger (61) and the expander (43).

2. The air conditioning system of claim 1, further comprising: a generator (42) and an electrical storage device;

the expander (43) capable of driving the generator (42) to generate electricity by using a pressure difference of the refrigerant;

the electric storage device is capable of storing electric energy generated by the generator.

3. Air conditioning system according to claim 1 or 2, wherein a first switching element is provided in a line between the second port of the outdoor heat exchanger (61) and the first four-way valve (51), and a second switching element is provided in a line between the first port of the outdoor heat exchanger (61) and the second four-way valve (52).

4. The air conditioning system according to claim 1 or 2, further comprising: a regenerator (65); the regenerator (65) comprising: a first heat return circuit and a second heat return circuit;

the first heat return line being provided in a line between a first port of the second four-way valve (52) and a first port of the expander (43); a second port of the second four-way valve (52) being communicable to a first port of the outdoor heat exchanger (61); a third port of the second four-way valve (52) connected to a second port of the expander (43); a fourth port of the second four-way valve (52) is communicated to a first port of the indoor heat exchanger (63);

the second heat return pipeline is arranged in a pipeline between a first port of the first four-way valve (51) and a suction port of the compressor (1); a second port of the first four-way valve (51) is communicated to a second port of the indoor heat exchanger (63); a third port of the first four-way valve (51) is communicated to an exhaust port of the compressor (1); a fourth port of the first four-way valve (51) being communicable to a second port of the outdoor heat exchanger (61);

under the condition of refrigerating operation of the air conditioning system, the refrigerant is compressed by the compressor (1), enters the outdoor heat exchanger (61) through the first four-way valve (51), passes through the heat regenerator (65) and then enters the expander (43), and the expander (43) is driven by the refrigerant to rotate and transmits power to the generator (42) to generate electricity;

under the condition of heating operation of the air conditioning system, the refrigerant is compressed by the compressor (1), enters the indoor heat exchanger (63) through the first four-way valve (51), passes through the heat regenerator (65) and enters the expander (43), and the expander (43) is driven by the refrigerant to rotate and transmits power to the generator (42) to generate electricity.

5. The air conditioning system according to claim 4, wherein in a case where the air conditioning system further includes a first switching element and a second switching element, the first switching element includes: a first solenoid valve (81); the second switching element includes: a second solenoid valve (82);

wherein the first solenoid valve (81) is arranged in a pipeline between a fourth port of the first four-way valve (51) and a second port of the outdoor heat exchanger (61); the second electromagnetic valve (82) is arranged in a pipeline between a fourth port of the second four-way valve (52) and a first port of the indoor heat exchanger (63);

under the condition that the air conditioning system is shut down in a refrigeration operation mode, the first electromagnetic valve (81) and the second electromagnetic valve (82) are closed; opening the second solenoid valve (82) under the condition that the pressure difference of the refrigerant between the outdoor heat exchanger (61) and the indoor heat exchanger (63) is enough to drive the expander (43), wherein the refrigerant enters the expander (43) through the second solenoid valve (82) and the second four-way valve (52) to drive the generator (42) to generate electricity;

in the case of shutdown of the air conditioning system heating operation, the first solenoid valve (81) and the second solenoid valve (82) are both closed; and under the condition that the pressure difference of the refrigerant between the indoor heat exchanger (63) and the outdoor heat exchanger (61) is enough to drive the expander (43), the second electromagnetic valve (82) is opened, and the refrigerant enters the expander (43) through the second electromagnetic valve (82) and the second four-way valve (52) to drive the generator (42) to generate electricity.

6. The air conditioning system according to claim 1 or 2, further comprising: a gas-liquid separator (2); and the gas-liquid separator (2) is arranged in an air inlet pipeline of an air suction port of the compressor (1).

7. The air conditioning system according to claim 1 or 2, wherein the outdoor heat exchanger (61) is further provided with an outdoor heat exchange fan (62); and/or the indoor heat exchanger (63) is also provided with an indoor heat exchange fan (64).

8. A control method of an air conditioning system as claimed in any one of claims 1 to 7, characterized by comprising:

controlling the compressor (1), the first four-way valve (51) and the second four-way valve (52) to control the air conditioning system to perform a cooling operation or a heating operation;

in the case that the air conditioning system further comprises a generator (42), controlling the generator (42) to generate electricity under the driving of the expander (43) during the cooling operation or the heating operation of the air conditioning system;

in the case where the air conditioning system further includes a first solenoid valve (81) and a second solenoid valve (82), in the case where the air conditioning system is stopped in cooling operation or heating operation, the switching of the first solenoid valve (81) and the second solenoid valve (82) is controlled, and the generator (42) is controlled to generate electricity under the driving of the expander (43).

9. The control method of an air conditioning system according to claim 8, wherein controlling the opening and closing of the first solenoid valve (81) and the second solenoid valve (82) and controlling the generator (42) to generate power under the driving of the expander (43) in the case where the air conditioning system is stopped in the cooling operation includes:

under the condition that the air conditioning system is shut down in a refrigerating operation mode, controlling the first electromagnetic valve (81) and the second electromagnetic valve (82) to be closed;

acquiring the outdoor environment temperature of the air conditioning system, and recording as a first outdoor environment temperature; acquiring the pressure of an air suction port of the compressor (1), and recording the pressure as a first low-pressure;

determining the temperature of the air conditioning system according to the first low-pressure, and recording the temperature as a first low-pressure temperature;

in the case that the temperature difference between the first outdoor environment temperature and the first low-pressure temperature is larger than a first set temperature, the pressure difference of the refrigerant between the outdoor heat exchanger (61) and the indoor heat exchanger (63) is determined to be enough to drive the expander (43), the second electromagnetic valve (82) is controlled to be opened, and the refrigerant enters the expander (43) through the second electromagnetic valve (82) and the second four-way valve (52) to drive the generator (42) to generate electricity.

10. The control method of an air conditioning system according to claim 8, wherein in a case where the air conditioning system is stopped in a heating operation, controlling the opening and closing of the first solenoid valve (81) and the second solenoid valve (82), and controlling the generator (42) to generate power under the driving of the expander (43), further comprises:

under the condition that the air conditioning system is stopped in heating operation, controlling the first electromagnetic valve (81) and the second electromagnetic valve (82) to be closed;

acquiring the outdoor environment temperature of the air conditioning system, and recording as a second outdoor environment temperature; acquiring the pressure of an air suction port of the compressor (1), and recording the pressure as a second low-pressure;

determining the temperature of the air conditioning system according to the second low-pressure, and recording the temperature as a second low-pressure temperature;

under the condition that the temperature difference between the second low-pressure temperature and the second outdoor environment temperature is larger than a second set temperature, the pressure difference of the refrigerant between the indoor heat exchanger (63) and the outdoor heat exchanger (61) is enough to drive the expander (43), the second electromagnetic valve (82) is controlled to be opened, and the refrigerant enters the expander (43) through the second electromagnetic valve (82) and the second four-way valve (52) to drive the generator (42) to generate electricity.

Technical Field

The invention belongs to the technical field of air conditioning systems, particularly relates to an air conditioning system and a control method thereof, and particularly relates to an environment-friendly air source heat pump system with a power generation function and a control method thereof.

Background

The emission of Freon gas can destroy the atmosphere, cause greenhouse effect and lead to global temperature rise and other environmental problems. The refrigerant is widely used as a working medium of an air conditioning system, and as China officially accepts and executes the Montreal protocol-based California correction Law, the supervision of the fluorine-containing refrigerant is gradually tightened.

CO₂Is one of natural environment-friendly refrigerant working media, can also play a role of fixing carbon if being used as a refrigerant, but because of CO₂The critical temperature is low, and the refrigeration energy efficiency is poor when the environmental temperature is high, so that the wide application is not always realized.

The above is only for the purpose of assisting understanding of the technical aspects of the present invention, and does not represent an admission that the above is prior art.

Disclosure of Invention

The invention aims to provide an air conditioning system and a control method thereof, aiming at solving the problem that CO is adopted in the air conditioning system₂When used as a refrigerant, the refrigerant has poor refrigeration efficiency when the ambient temperature is high, and the purpose is achieved by adopting CO in an air conditioning system₂When the refrigerant is used, the effect of the energy efficiency ratio in high-temperature refrigeration can be improved by throttling the refrigerant with the expander.

The present invention provides an air conditioning system comprising: a compressor, an outdoor heat exchanger and an indoor heat exchanger; the compressor, the outdoor heat exchanger and the indoor heat exchanger are communicated through a pipeline; the air conditioning system adopts CO₂As a refrigerant; in the air conditioning system, an expander is provided in a piping between a first port of the outdoor heat exchanger and a first port of the indoor heat exchanger; change outside the roomA first four-way valve is arranged in a pipeline between the second port of the heat exchanger and the compressor, and a second four-way valve is arranged between the first port of the outdoor heat exchanger and the expander.

In some embodiments, further comprising: a generator and an electrical storage device; the expander can drive the generator to generate power by using the pressure difference of the refrigerant; the electric storage device is capable of storing electric energy generated by the generator.

In some embodiments, a first switching element is disposed in a line between the second port of the outdoor heat exchanger and the first four-way valve, and a second switching element is disposed in a line between the first port of the outdoor heat exchanger and the second four-way valve.

In some embodiments, further comprising: a heat regenerator; the regenerator includes: a first heat return circuit and a second heat return circuit; the first heat return pipeline is arranged in a pipeline between a first port of the second four-way valve and a first port of the expansion machine; the second port of the second four-way valve can be communicated to the first port of the outdoor heat exchanger; a third port of the second four-way valve connected to the second port of the expander; a fourth port of the second four-way valve is communicated to a first port of the indoor heat exchanger; the second heat return pipeline is arranged in a pipeline between a first port of the first four-way valve and a suction port of the compressor; the second port of the first four-way valve is communicated to the second port of the indoor heat exchanger; the third port of the first four-way valve is communicated to the exhaust port of the compressor; a fourth port of the first four-way valve can be communicated to a second port of the outdoor heat exchanger; under the condition that the air conditioning system operates in a refrigerating mode, the refrigerant is compressed by the compressor, enters the outdoor heat exchanger through the first four-way valve, enters the expander through the heat regenerator, is driven to rotate by the refrigerant and transmits power to the generator to generate power; under the condition of heating operation of the air conditioning system, the refrigerant is compressed by the compressor, enters the indoor heat exchanger through the first four-way valve, enters the expander through the heat regenerator, is driven by the refrigerant to rotate, and transmits power to the generator to generate power.

In some embodiments, in a case where the air conditioning system further includes a first switching element and a second switching element, the first switching element includes: a first solenoid valve; the second switching element includes: a second solenoid valve; the first electromagnetic valve is arranged in a pipeline between a fourth port of the first four-way valve and a second port of the outdoor heat exchanger; the second electromagnetic valve is arranged in a pipeline between a fourth port of the second four-way valve and the first port of the indoor heat exchanger; under the condition that the air conditioning system is shut down in refrigeration operation, the first electromagnetic valve and the second electromagnetic valve are both closed; under the condition that the pressure difference of the refrigerant between the outdoor heat exchanger and the indoor heat exchanger is enough to drive the expander, the second electromagnetic valve is opened, the refrigerant enters the expander through the second electromagnetic valve and the second four-way valve, and the generator is driven to generate electricity; under the condition that the air conditioning system is shut down in heating operation, the first electromagnetic valve and the second electromagnetic valve are both closed; and under the condition that the pressure difference of the refrigerant between the indoor heat exchanger and the outdoor heat exchanger is enough to drive the expander, the second electromagnetic valve is opened, and the refrigerant enters the expander through the second electromagnetic valve and the second four-way valve to drive the generator to generate power.

In some embodiments, further comprising: a gas-liquid separator; and the gas-liquid separator is arranged in an air inlet pipeline of an air suction port of the compressor.

In some embodiments, the outdoor heat exchanger is further provided with an outdoor heat exchange fan; and/or the indoor heat exchanger is also provided with an indoor heat exchange fan.

In accordance with another aspect of the present invention, there is provided a method for controlling an air conditioning system, including: controlling the compressor, the first four-way valve and the second four-way valve to control the air-conditioning system to perform cooling operation or heating operation; in the case that the air conditioning system further comprises a generator, controlling the generator to generate electricity under the driving of the expansion machine during the cooling operation or the heating operation of the air conditioning system; under the condition that the air conditioning system further comprises a first electromagnetic valve and a second electromagnetic valve, under the condition that the air conditioning system stops in cooling operation or heating operation, the switches of the first electromagnetic valve and the second electromagnetic valve are controlled, and the generator is controlled to generate electricity under the driving of the expansion machine.

In some embodiments, in the case where the air conditioning system is in a refrigeration operation stop, controlling the switching of the first solenoid valve and the second solenoid valve, and controlling the generator to generate power under the driving of the expander includes: under the condition that the air conditioning system is shut down in refrigeration operation, controlling the first electromagnetic valve and the second electromagnetic valve to be closed; acquiring the outdoor environment temperature of the air conditioning system, and recording as a first outdoor environment temperature; acquiring the pressure of an air suction port of the compressor, and recording the pressure as a first low-pressure; determining the temperature of the air conditioning system according to the first low-pressure, and recording the temperature as a first low-pressure temperature; and under the condition that the temperature difference between the first outdoor environment temperature and the first low-pressure temperature is greater than a first set temperature, determining that the pressure difference of the refrigerant between the outdoor heat exchanger and the indoor heat exchanger is enough to drive the expander, controlling the second electromagnetic valve to be opened, and enabling the refrigerant to enter the expander through the second electromagnetic valve and the second four-way valve to drive the generator to generate power.

In some embodiments, in a case where the air conditioning system is stopped in a heating operation, controlling the switching of the first solenoid valve and the second solenoid valve, and controlling the generator to generate power under the driving of the expander, further includes: under the condition that the air conditioning system is stopped in heating operation, controlling the first electromagnetic valve and the second electromagnetic valve to be closed; acquiring the outdoor environment temperature of the air conditioning system, and recording as a second outdoor environment temperature; acquiring the pressure of an air suction port of the compressor, and recording the pressure as a second low-pressure; determining the temperature of the air conditioning system according to the second low-pressure, and recording the temperature as a second low-pressure temperature; and under the condition that the temperature difference between the second low-pressure temperature and the second outdoor environment temperature is greater than a second set temperature, the pressure difference of the refrigerant between the indoor heat exchanger and the outdoor heat exchanger is enough to drive the expander, the second electromagnetic valve is controlled to be opened, and the refrigerant enters the expander through the second electromagnetic valve and the second four-way valve to drive the generator to generate power.

Thus, the scheme of the invention, by adopting CO₂As a refrigerant of the air conditioning system, an expander (such as an expander 43) is arranged between an outdoor heat exchanger (such as an outdoor heat exchanger 61) and an indoor heat exchanger (such as an indoor heat exchanger 63) of the air conditioning system, a first solenoid valve (such as a first solenoid valve 81) and a first four-way valve (such as a first four-way valve 51) are arranged on a pipeline between the outdoor heat exchanger and a compressor, a second solenoid valve (such as a second solenoid valve 82) and a second four-way valve (such as a second four-way valve 52) are arranged between the outdoor heat exchanger and the expander, and the control of the air conditioning system is realized by controlling the on and off of the first solenoid valve and the second solenoid valve; thus, by using CO in the air conditioning system₂When the refrigerant is used, the energy efficiency ratio during high-temperature refrigeration can be improved by throttling the refrigerant with an expander.

Furthermore, according to the scheme of the invention, a generator (such as a generator 42) and an electric storage device (such as a storage battery or a power grid 41) are also arranged, so that power can be generated by utilizing the pressure difference of the refrigerant, power generation can be realized in both the operation state and the shutdown state of the heat pump, energy conservation and emission reduction are realized, and the comprehensive utilization rate of energy is improved.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of an air conditioning system according to the present invention;

FIG. 2 is a schematic diagram of an embodiment of an air source heat pump system with power generation;

FIG. 3 is a schematic diagram of a control structure of an embodiment of the air source heat pump system with power generation function shown in FIG. 2;

FIG. 4 is a schematic diagram of an embodiment of an air source heat pump system refrigeration cycle;

FIG. 5 is a schematic diagram of an embodiment of a heating cycle of the air-source heat pump system;

FIG. 6 is a schematic diagram of an embodiment of the expander operating in power generation during a refrigeration shutdown of the air source heat pump system;

FIG. 7 is a schematic diagram of an embodiment of an expander power generation operation during a heating shutdown of an air source heat pump system;

FIG. 8 is a flowchart illustrating an embodiment of a method for controlling an air conditioning system according to the present invention;

FIG. 9 is a schematic flow chart illustrating one embodiment of a method of the present invention for controlling a generator to generate power in the event of a shutdown of a cooling operation;

FIG. 10 is a schematic flow chart illustrating an embodiment of the method of the present invention for controlling the generator to generate power in the event of a shutdown of the heating operation.

The reference numbers in the embodiments of the present invention are as follows, in combination with the accompanying drawings:

1-a compressor; 2-a gas-liquid separator; 3-a central controller; 41-accumulator (or grid); 42-a generator; 43-an expander; 51-a first four-way valve; 52-a second four-way valve; 61-outdoor heat exchanger; 62-outdoor heat exchange fan; 63-indoor heat exchanger; 64-indoor heat exchange fan; 65-a heat regenerator; 71-outdoor temperature sensor; 72-a low pressure sensor; 73-high pressure sensor; 81-a first solenoid valve; 82-second solenoid valve.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

According to an embodiment of the present invention, there is provided an air conditioning system. Referring to fig. 1, a schematic diagram of an embodiment of the apparatus of the present invention is shown. The air conditioning system may include: a compressor 1, an outdoor heat exchanger 61, and an indoor heat exchanger 63. The compressor 1, the outdoor heat exchanger 61 and the indoor heat exchanger 63 are communicated through pipelines. The air conditioning system adopts CO₂As a refrigerant.

In the air conditioning system, an expander 43 is provided in a pipe between the outdoor heat exchanger 61 and the indoor heat exchanger 63, and particularly, an expander 43 is provided in a pipe between a first port of the outdoor heat exchanger 61 and a first port of the indoor heat exchanger 63. That is, the expander is disposed in a pipe between the first port of the outdoor heat exchanger 61 and the first port of the indoor heat exchanger 63.

The air conditioning system further includes: a control unit, such as a central controller 3. Wherein the control unit is configured to control the compressor 1 to work so as to at least realize the cooling operation of the air conditioning system.

A first four-way valve 51 is provided in a pipe between the second port of the outdoor heat exchanger 61 and the compressor 1, and a second four-way valve 52 is provided between the first port of the outdoor heat exchanger 61 and the expander 43.

The control unit is further configured to control the first four-way valve 51 and the second four-way valve 52 to control the air conditioning system to operate in a switching manner at least between a cooling mode and a heating mode.

In the scheme of the invention, the heat pump system adopts the expansion machine (such as the expansion agent 43) for throttling, thereby reducing the dryness of the inlet of the evaporator, improving the refrigerating capacity of the refrigerant per unit mass, improving the energy efficiency ratio during high-temperature refrigeration, and solving the problem of using CO for refrigeration₂The heat pump air conditioner has the problem of low refrigeration energy efficiency in a high-temperature environment.

In some embodiments, further comprising: a generator 42 and an electrical storage device. An electrical storage device, such as a battery or grid 41.

The expander 43 is drivingly connected to the generator 42, and can drive the generator 42 to generate electricity by using the pressure difference of the refrigerant.

The electric storage device is connected to the generator 42 and can store electric energy generated by the generator.

In the scheme of the invention, the heat pump system generates power by utilizing pressure difference, realizes power generation under both the operation and shutdown states of the heat pump, and timely stores the generated power in a storage battery or uploads the generated power to a power grid, such as a storage battery (or the power grid) 41, thereby realizing energy conservation and emission reduction, improving the comprehensive utilization rate of energy, and solving the problem that the power consumption of a user is increased due to larger refrigeration power consumption of a heat pump air conditioner.

In some embodiments, a first switching element is disposed in a pipeline between the second port of the outdoor heat exchanger 61 and the first four-way valve 51, and a second switching element is disposed in a pipeline between the first port of the outdoor heat exchanger 61 and the second four-way valve 52. A first switching element such as a first solenoid valve 81 and a second switching element such as a second solenoid valve 82.

That is, an expander 43 is provided in a pipeline between a first port of the outdoor heat exchanger 61 and a first port of the indoor heat exchanger 63, a first switching element and a first four-way valve 51 are provided in a pipeline between a second port of the outdoor heat exchanger 61 and the compressor 1, and a second switching element and a second four-way valve 52 are provided between the first port of the outdoor heat exchanger 61 and the expander 43.

The control unit is further configured to control the switching of a first switching element, such as a first solenoid valve 81, and a second switching element, such as a second solenoid valve 82, to control the air conditioning system to continue generating power in a shutdown state.

The invention provides an air conditioning system (such as an environment-friendly air source heat pump) with a power generation function and a control method thereof, and adopts an environment-friendly working medium CO₂As a refrigerant for air conditioning systems (e.g., heat pump systems), to reduce carbon emissions from heat pump systemsThe high air conditioning system is energy efficient for cooling in high temperature environments. And the expansion work recovery power generation of refrigeration and heating operation is realized through the design of the heat pump system.

In some embodiments, further comprising: a regenerator 65. The regenerator 65 includes: a first heat return circuit and a second heat return circuit. That is, the regenerator 65 has therein a first heat recovery circuit and a second heat recovery circuit that can exchange heat with each other.

The second four-way valve 52 has a first port, a second port, a third port and a fourth port. The first heat return line is provided in a line between the first port of the second four-way valve 52 and the first port of the expander 43. A second port of the second four-way valve 52 is connectable to a first port of the outdoor heat exchanger 61. A third port of the second four-way valve 52 is connected to a second port of the expander 43. The fourth port of the second four-way valve 52 is communicated to the first port of the indoor heat exchanger 63.

The first four-way valve 51 has a first port, a second port, a third port and a fourth port. The second heat circuit is provided in a line between the first port of the first four-way valve 51 and the suction port of the compressor 1. A second port of the first four-way valve 51 is communicated to a second port of the indoor heat exchanger 63. A third port of the first four-way valve 51 is communicated to an exhaust port of the compressor 1. A fourth port of the first four-way valve 51 is connectable to a second port of the outdoor heat exchanger 61.

Fig. 2 is a schematic structural diagram of an embodiment of an air source heat pump system with a power generation function, and fig. 3 is a schematic control structural diagram of an embodiment of the air source heat pump system with a power generation function shown in fig. 2. As shown in fig. 2 and 3, the air source heat pump system having a power generation function includes: a compressor 1, an outdoor heat exchanger 61, an outdoor heat exchange fan 62, a heat regenerator 65, an expander 43, a generator 42, a storage battery (or a power grid) 41, an indoor heat exchanger 63, an indoor heat exchange fan 64, a first four-way valve 51, a second four-way valve 52, the outdoor heat exchange fan 62, the indoor heat exchange fan 64, a refrigerant and the like,the air source heat pump system can apply CO₂The refrigerant is energy-saving and environment-friendly.

In the case of the air conditioning system performing a cooling operation, the refrigerant is compressed by the compressor 1, enters the outdoor heat exchanger 61 through the first four-way valve 51, passes through the heat regenerator 65, and enters the expander 43, and the expander 43 is driven to rotate by the refrigerant and transmits power to the generator 42 to generate power.

Fig. 4 is a schematic structural diagram of an embodiment of a refrigeration operation cycle of the air source heat pump system. Fig. 4 is a schematic diagram of a refrigeration operation cycle of the heat pump system, in which a low-temperature and low-pressure gaseous refrigerant is compressed by the compressor 1 and then changed into a high-temperature and high-pressure state, and the compressed gaseous refrigerant first enters the outdoor heat exchanger 61 through the first four-way valve 51 to be cooled, and then enters the expander 43 through the heat regenerator 65, and the expander 43 is driven by the high-pressure refrigerant to rotate and transmit power to the generator 42 to generate electricity. The electric energy generated by the generator 42 will be stored in the accumulator or uploaded to the grid, i.e. to the accumulator (or grid) 41. The refrigerant expanded by the expander 43 changes into a low-temperature low-pressure gas-liquid two-phase state, enters the indoor heat exchanger 63 for evaporation, passes through the heat regenerator 65, enters the gas-liquid separator 2, finally returns to the air suction port of the compressor 1 for compression, and is circulated continuously.

In summer, the dryness of the refrigerant expanded by the expander 43 at the inlet of the indoor heat exchanger 63 is reduced, thereby increasing the refrigerating capacity per unit mass of the system. In addition, the high-pressure refrigerant drives the expander 43 to generate power, so that the power consumption of the heat pump system is reduced, the refrigerating capacity of the heat pump system can be effectively improved and the refrigerating power consumption can be reduced during refrigerating operation, and under the condition that the pressure of the indoor heat exchanger 63 is unchanged due to the fact that the pressure of the outdoor heat exchanger 61 is higher in high-temperature weather, the pressure difference between two ends of the expander 43 is increased, the kinetic energy for driving the generator 42 is increased, the power generation amount is correspondingly increased, and therefore the high-pressure refrigerant driving expander has a better energy-saving effect under the high-temperature weather.

In the case of the heating operation of the air conditioning system, the refrigerant is compressed by the compressor 1, then enters the indoor heat exchanger 63 through the first four-way valve 51, passes through the heat regenerator 65, and then enters the expander 43, and the expander 43 is driven by the refrigerant to rotate and transmits power to the generator 42 to generate electricity.

Fig. 5 is a schematic structural diagram of an embodiment of a heating operation cycle of the air-source heat pump system. Fig. 5 is a diagram of a heating operation cycle of the heat pump system, and differs from the refrigeration cycle in that both the first four-way valve 51 and the second four-way valve 52 are reversed. At this time, the low-temperature low-pressure gas refrigerant is compressed by the compressor 1 and then becomes a high-temperature high-pressure state, the gas refrigerant firstly enters the indoor heat exchanger 63 through the first four-way valve 51 to exchange heat, the gas refrigerant enters the expander 43 after passing through the heat regenerator 65, the expander 43 is driven to rotate by the high-pressure refrigerant and transmits power to the generator 42 to generate electricity, the generated electricity is stored in the storage battery or is transmitted to the power grid, the refrigerant expanded by the expander 43 becomes a low-temperature low-pressure gas-liquid two-phase state, then enters the outdoor heat exchanger 61 to be evaporated, the gas-liquid separator 2 after passing through the heat regenerator 65, and finally returns to the air suction port of the compressor 1 to be compressed, so that the cycle is continuous.

In winter, the dryness of the refrigerant expanded by the expander 43 at the inlet of the outdoor unit is reduced, so that the unit mass heating capacity of the system is improved, in addition, the high-pressure refrigerant drives the expander 43 to generate electricity and can be used for driving the compressor 1, and the power consumption of the system is reduced, so that the system can effectively improve the heating capacity and reduce the heating power consumption during heating operation, and under the condition of low temperature, because the pressure of the outdoor heat exchanger 61 is lower, under the condition that the pressure of the indoor heat exchanger 63 is unchanged, the pressure difference between two ends of the expander 43 is increased, the kinetic energy for driving the generator 42 is increased, and the generated energy is correspondingly increased, so that the system has a better energy-saving effect under the low temperature.

In some embodiments, in a case where the air conditioning system further includes a first switching element and a second switching element, the first switching element includes: the first solenoid valve 81. The second switching element includes: a second solenoid valve 82.

Wherein, the first solenoid valve 81 is disposed in a pipeline between the fourth port of the first four-way valve 51 and the second port of the outdoor heat exchanger 61. The second solenoid valve 82 is disposed in a pipeline between the fourth port of the second four-way valve 52 and the first port of the indoor heat exchanger 63.

In the case where the air conditioning system is stopped in the cooling operation, both the first solenoid valve 81 and the second solenoid valve 82 are closed. In the case where the pressure difference of the refrigerant between the outdoor heat exchanger 61 and the indoor heat exchanger 63 is sufficient to drive the expander 43, the second solenoid valve 82 is opened, and the refrigerant enters the expander 43 through the second solenoid valve 82 and the second four-way valve 52, thereby driving the generator 42 to generate electricity.

The above is the heat pump system operation power generation mode when the heat pump system is in operation. Next, the power generation mode of the heat pump system in the heat pump system off state will be exemplified.

Fig. 6 is a schematic structural diagram of an embodiment of the power generation operation of the expander in the refrigeration shutdown of the air source heat pump system. At the time of stop of the cooling operation, both the first solenoid valve 81 and the second solenoid valve 82 are closed, disconnecting the outdoor heat exchanger 61 from the first four-way valve 51 and the second four-way valve 52. Since the outdoor ambient temperature is higher than the indoor ambient temperature at this time, the pressure of the refrigerant in the outdoor heat exchanger 61 will be higher than that of the refrigerant in the indoor heat exchanger 63 as the heat exchange is sufficiently performed. As shown in fig. 2 and 3, the outdoor temperature sensor 71 collects a first outdoor ambient temperature T_out1The low pressure sensor 72 transmits the low pressure P of the heat pump system to the central controller 3_s1The refrigerant is fed back to the central controller 3, and can be in a gas-liquid two-phase state under the stop state according to the low-pressure P_s1Calculating to obtain the first low-pressure temperature T of the heat pump system at the moment_s1When the first outdoor ambient temperature T_out1First low-pressure temperature T_s1>When the first set temperature is X1, 5 is equal to or less than the first set temperature X1 is equal to or less than 20, it is determined that the pressure difference between the outdoor heat exchanger 61 and the indoor heat exchanger 63 is sufficient to drive the expander 43 to rotate and do work, at this time, the second electromagnetic valve 82 is opened, as shown in fig. 6, the refrigerant enters the expander 43 through the second electromagnetic valve 82 and the second four-way valve 52, so as to drive the generator 42 to generate power, and the power generation of the heat pump system in the shutdown state in hot days in summer (i.e., when the outdoor ambient temperature is higher than the indoor ambient temperature) is realized.

In accordance with the low pressure P_s1Calculating to obtain the first low-pressure temperature T of the heat pump system at the moment_s1Specifically, the following may be: for a specific refrigerant, in a gas-liquid two-phase state, one pressure value corresponds to one unique temperature value, the pressure and the temperature are in one-to-one correspondence, and the correspondence can be obtained by looking up a table (a correspondence table obtained in advance according to empirical values), and the correspondence is written in a control program.

In the case where the air conditioning system is stopped in the heating operation, both the first solenoid valve 81 and the second solenoid valve 82 are closed. In the case where the pressure difference of the refrigerant between the indoor heat exchanger 63 and the outdoor heat exchanger 61 is sufficient to drive the expander 43, the second solenoid valve 82 is opened, and the refrigerant enters the expander 43 through the second solenoid valve 82 and the second four-way valve 52, thereby driving the generator 42 to generate electricity.

Fig. 7 is a schematic structural diagram of an embodiment of an expander power generation operation in a heating shutdown of the air source heat pump system. At the time of shutdown of the heating operation, both the first solenoid valve 81 and the second solenoid valve 82 are closed, disconnecting the outdoor heat exchanger 61 from the first four-way valve 51 and the second four-way valve 52. Since the indoor ambient temperature is higher than the outdoor ambient temperature at this time, the pressure of the refrigerant in the indoor heat exchanger 63 will be higher than the pressure of the refrigerant in the outdoor heat exchanger 61 as the heat exchange proceeds sufficiently. As shown in fig. 2 and 3, the outdoor temperature sensor 71 collects the second outdoor ambient temperature T_out2The low pressure sensor 72 transmits the system low pressure P to the central controller 3_s2The refrigerant is fed back to the central controller 3, and can be in a gas-liquid two-phase state under the stop state according to the low-pressure P_s2Calculating to obtain a second low-pressure temperature T of the heat pump system at the moment_s2When the second low-pressure temperature T is reached_s2-a second outdoor ambient temperature T_out2>When the second set temperature X2 is greater than or equal to 5 and less than or equal to 20, it is determined that the pressure difference between the indoor heat exchanger 63 and the outdoor heat exchanger 61 is sufficient to drive the expander 43 to do work, and at this time, the second solenoid valve 82 is opened, as shown in FIG. 7, the refrigerant passes through the second solenoid valve 82 and the second four-way valve52 into the expander 43, thereby driving the generator 42 to generate power, and realizing the power generation of the heat pump system in the shutdown state in cold days in winter (i.e. the outdoor ambient temperature is lower than the indoor ambient temperature).

Fig. 2 to 7 illustrate examples of the heat pump system (i.e., an air source heat pump system) in which the first four-way valve 51 and the second four-way valve 52 are changed, and different switching modes of the first four-way valve 51 and the second four-way valve 52 correspond to different heat pump system cycles, that is, different application scenarios.

In the scheme of the invention, the heat pump system can adopt CO₂As refrigerant and use of CO₂The high pressure feature can increase the driving force of the expander 43 to increase the power generation capacity, and CO₂The natural working medium has good environmental protection characteristic and is one of the ultimate choices of future refrigerants. That is, the present invention employs the expander 43 and CO₂The heat pump system is integrally designed, external industrial waste heat is not required for driving, the refrigeration, heating and power generation functions can be realized simultaneously, the temperature difference of the environment can be utilized to generate power in a shutdown state, the refrigeration and heating functions are realized, the power generation function is realized, and the shutdown power generation function is realized by adopting an environment-friendly refrigerant.

In some embodiments, further comprising: a gas-liquid separator 2. The gas-liquid separator 2 is provided in an intake line of an intake port of the compressor 1. In the case where the air conditioning system further includes a regenerator 65, the gas-liquid separator 2 is disposed in a pipe between the second regenerative tube of the regenerator 65 and the suction port of the compressor 1.

In some embodiments, the outdoor heat exchanger 61 is further provided with an outdoor heat exchange fan 62. And/or the indoor heat exchanger 63 is also provided with an indoor heat exchange fan 64.

As shown in fig. 2 and 3, the air source heat pump system with power generation function specifically includes a compressor 1, an outdoor heat exchanger 61, an outdoor heat exchange fan 62, a heat regenerator 65, an expander 43, a generator 42, a central controller 3, a battery (or a power grid) 41, an indoor heat exchanger 63, an indoor heat exchange fan 64, a gas-liquid separator 2, a temperature sensor (e.g., an outdoor temperature sensor 71), a pressure sensor (e.g., a low-pressure sensor 72 and a high-pressure sensor 73), a first four-way valve 51, a second four-way valve 52, the outdoor heat exchange fan 62, the indoor heat exchange fan 64, a first electromagnetic valve 81, a second electromagnetic valve 82, and a refrigerant.

The compressor 1, the indoor and outdoor heat exchange fans (such as the outdoor heat exchange fan 62 and the indoor heat exchange fan 64), the first four-way valve 51, the second four-way valve 52, the first electromagnetic valve 81, the second electromagnetic valve 82, the temperature and pressure sensors (such as the outdoor temperature sensor 71, the low-pressure sensor 72 and the high-pressure sensor 73), the generator 42 and the storage battery (or power grid) 41 are all connected with the central controller 3, and the temperature and pressure sensors (such as the outdoor temperature sensor 71, the low-pressure sensor 72 and the high-pressure sensor 73) feed collected information back to the central controller 3. The central controller 3 is powered by a battery (or grid) 41. The central controller 3 is used to control the compressor 1, the first four-way valve 51, the second four-way valve 52, the first solenoid valve 81, the second solenoid valve 82, and the like. The high pressure sensor 73 can detect the high pressure when the system is running, and as an important reference for controlling the running of the system, the high pressure sensor needs to be stopped for maintenance when the high pressure is abnormal.

As shown in fig. 2 and 3, the expander 43 is connected between the outdoor heat exchanger 61 and the indoor heat exchanger 63, and when the heat pump system is operated, the first solenoid valve 81 and the second solenoid valve 82 are in a communication state, and the high-pressure refrigerant drives the expander 43 to rotate when passing through the expander 43, thereby driving the generator 42 to generate electricity. The electrical energy generated by the generator 42 may be stored in a battery or uploaded to the grid, i.e. to the battery (or grid) 41.

According to the scheme of the invention, based on the principle that the pressure difference of the refrigerant can drive the expander 43 to do work for power generation and effectively recover the power generation, the air conditioning system and the storage battery/power grid charging system are designed in a fusion manner, and the power generated by the expander 43 is fully recovered, so that on one hand, the refrigerating capacity of the heat pump system is improved, and meanwhile, the power consumption of the refrigerating and heating operation can be reduced, and in a shutdown state, the power generation and energy storage can be realized by utilizing the indoor and outdoor temperature difference.

By adopting the technical scheme of the invention, CO is adopted₂As a refrigerant of the air conditioning system, an expander (e.g., expander 43) is disposed between an outdoor heat exchanger (e.g., outdoor heat exchanger 61) and an indoor heat exchanger (e.g., indoor heat exchanger 63) of the air conditioning system, a first solenoid valve (e.g., first solenoid valve 81) and a first four-way valve (e.g., first four-way valve 51) are disposed on a pipeline between the outdoor heat exchanger and the compressor, a second solenoid valve (e.g., second solenoid valve 82) and a second four-way valve (e.g., second four-way valve 52) are disposed between the outdoor heat exchanger and the expander, and the air conditioning system is controlled by controlling the opening and closing of the first solenoid valve and the second solenoid valve. Thus, by using CO in the air conditioning system₂When the refrigerant is used, the energy efficiency ratio during high-temperature refrigeration can be improved by throttling the refrigerant with an expander.

According to an embodiment of the present invention, there is also provided a control method of an air conditioning system corresponding to the air conditioning system, as shown in fig. 8, which is a schematic flow chart of an embodiment of the method of the present invention. The control method of the air conditioning system may include: step S110 to step S130.

At step S110, the compressor 1, the first four-way valve 51, and the second four-way valve 52 are controlled to control the air conditioning system cooling operation or heating operation.

In step S120, in the case where the air conditioning system further includes the generator 42, the generator 42 is controlled to generate power under the driving of the expander 43 during the cooling operation or the heating operation of the air conditioning system.

Specifically, in the case of the air conditioning system performing a cooling operation, the refrigerant is compressed by the compressor 1, enters the outdoor heat exchanger 61 through the first four-way valve 51, passes through the heat regenerator 65, and enters the expander 43, and the expander 43 is driven by the refrigerant to rotate and transmits power to the generator 42 to generate power.

Fig. 4 is a schematic diagram of a refrigeration operation cycle of the heat pump system, in which a low-temperature and low-pressure gaseous refrigerant is compressed by the compressor 1 and then changed into a high-temperature and high-pressure state, and the compressed gaseous refrigerant first enters the outdoor heat exchanger 61 through the first four-way valve 51 to be cooled, and then enters the expander 43 through the heat regenerator 65, and the expander 43 is driven by the high-pressure refrigerant to rotate and transmit power to the generator 42 to generate electricity. The electric energy generated by the generator 42 will be stored in the accumulator or uploaded to the grid, i.e. to the accumulator (or grid) 41. The refrigerant expanded by the expander 43 changes into a low-temperature low-pressure gas-liquid two-phase state, enters the indoor heat exchanger 63 for evaporation, passes through the heat regenerator 65, enters the gas-liquid separator 2, finally returns to the air suction port of the compressor 1 for compression, and is circulated continuously.

In summer, the dryness of the refrigerant expanded by the expander 43 at the inlet of the indoor heat exchanger 63 is reduced, thereby increasing the refrigerating capacity per unit mass of the system. In addition, the high-pressure refrigerant drives the expander 43 to generate power, so that the power consumption of the heat pump system is reduced, the refrigerating capacity of the heat pump system can be effectively improved and the refrigerating power consumption can be reduced during refrigerating operation, and under the condition that the pressure of the indoor heat exchanger 63 is unchanged due to the fact that the pressure of the outdoor heat exchanger 61 is higher in high-temperature weather, the pressure difference between two ends of the expander 43 is increased, the kinetic energy for driving the generator 42 is increased, the power generation amount is correspondingly increased, and therefore the high-pressure refrigerant driving expander has a better energy-saving effect under the high-temperature weather.

In the case of the heating operation of the air conditioning system, the refrigerant is compressed by the compressor 1, then enters the indoor heat exchanger 63 through the first four-way valve 51, passes through the heat regenerator 65, and then enters the expander 43, and the expander 43 is driven by the refrigerant to rotate and transmits power to the generator 42 to generate electricity.

Fig. 5 is a diagram of a heating operation cycle of the heat pump system, and differs from the refrigeration cycle in that both the first four-way valve 51 and the second four-way valve 52 are reversed. At this time, the low-temperature low-pressure gas refrigerant is compressed by the compressor 1 and then becomes a high-temperature high-pressure state, the gas refrigerant firstly enters the indoor heat exchanger 63 through the first four-way valve 51 to exchange heat, the gas refrigerant enters the expander 43 after passing through the heat regenerator 65, the expander 43 is driven to rotate by the high-pressure refrigerant and transmits power to the generator 42 to generate electricity, the generated electricity is stored in the storage battery or is transmitted to the power grid, the refrigerant expanded by the expander 43 becomes a low-temperature low-pressure gas-liquid two-phase state, then enters the outdoor heat exchanger 61 to be evaporated, the gas-liquid separator 2 after passing through the heat regenerator 65, and finally returns to the air suction port of the compressor 1 to be compressed, so that the cycle is continuous.

In winter, the dryness of the refrigerant expanded by the expander 43 at the inlet of the outdoor unit is reduced, so that the unit mass heating capacity of the system is improved, in addition, the high-pressure refrigerant drives the expander 43 to generate electricity and can be used for driving the compressor 1, and the power consumption of the system is reduced, so that the system can effectively improve the heating capacity and reduce the heating power consumption during heating operation, and under the condition of low temperature, because the pressure of the outdoor heat exchanger 61 is lower, under the condition that the pressure of the indoor heat exchanger 63 is unchanged, the pressure difference between two ends of the expander 43 is increased, the kinetic energy for driving the generator 42 is increased, and the generated energy is correspondingly increased, so that the system has a better energy-saving effect under the low temperature.

In step S130, in the case where the air conditioning system further includes the first solenoid valve 81 and the second solenoid valve 82, in the case where the air conditioning system is stopped in the cooling operation or the heating operation, the switching of the first solenoid valve 81 and the second solenoid valve 82 is controlled, and the generator 42 is controlled to generate electricity under the driving of the expander 43. In the case of the cooling operation or the heating operation of the air conditioning system, both the first solenoid valve 81 and the second solenoid valve 82 are opened. The opening of the corresponding solenoid valve of the first solenoid valve 81 and the second solenoid valve 82 indicates the passage of the line controlled by the corresponding solenoid valve; the closing of the corresponding solenoid valve of the first solenoid valve 81 and the second solenoid valve 82 indicates the disconnection of the line controlled by the corresponding solenoid valve.

Specifically, in the case where the air conditioning system is stopped in the cooling operation, both the first solenoid valve 81 and the second solenoid valve 82 are closed. In the case where the pressure difference of the refrigerant between the outdoor heat exchanger 61 and the indoor heat exchanger 63 is sufficient to drive the expander 43, the second solenoid valve 82 is opened, and the refrigerant enters the expander 43 through the second solenoid valve 82 and the second four-way valve 52, thereby driving the generator 42 to generate electricity.

In the case where the air conditioning system is stopped in the heating operation, both the first solenoid valve 81 and the second solenoid valve 82 are closed. In the case where the pressure difference of the refrigerant between the indoor heat exchanger 63 and the outdoor heat exchanger 61 is sufficient to drive the expander 43, the second solenoid valve 82 is opened, and the refrigerant enters the expander 43 through the second solenoid valve 82 and the second four-way valve 52, thereby driving the generator 42 to generate electricity.

In some embodiments, in the case that the air conditioning system is in a cooling operation stop state in step S130, the opening and closing of the first solenoid valve 81 and the second solenoid valve 82 are controlled, and a specific process of generating power by the generator 42 under the driving of the expander 43 is controlled, as shown in the following exemplary description.

The following further describes, with reference to a schematic flow chart of an embodiment of the method of the present invention shown in fig. 9, a specific process of controlling the generator to generate power in step S130 in the case of the cooling operation shutdown, including: step S210 to step S240.

And step S210, controlling the first electromagnetic valve 81 and the second electromagnetic valve 82 to be closed under the condition that the air-conditioning system is in refrigeration operation stop.

Step S220, obtaining an outdoor ambient temperature of the air conditioning system, and recording as a first outdoor ambient temperature. The pressure at the suction port of the compressor 1 is obtained and recorded as a first low pressure.

And step S230, determining the temperature of the air conditioning system according to the first low-pressure, and recording the temperature as the first low-pressure temperature.

In step S240, when the temperature difference between the first outdoor ambient temperature and the first low-pressure temperature is greater than a first set temperature, it is determined that the pressure difference between the outdoor heat exchanger 61 and the indoor heat exchanger 63 is sufficient to drive the expander 43, and the second solenoid valve 82 is controlled to be opened, so that the refrigerant enters the expander 43 through the second solenoid valve 82 and the second four-way valve 52 to drive the generator 42 to generate power.

Fig. 6 is a schematic structural diagram of an embodiment of the power generation operation of the expander in the refrigeration shutdown of the air source heat pump system. At the time of stop of the cooling operation, both the first solenoid valve 81 and the second solenoid valve 82 are closed, disconnecting the outdoor heat exchanger 61 from the first four-way valve 51 and the second four-way valve 52. Because the outdoor environment temperature is at the momentHigher than the indoor ambient temperature, and as the heat exchange proceeds sufficiently, the pressure of the refrigerant in the outdoor heat exchanger 61 will be higher than the pressure of the refrigerant in the indoor heat exchanger 63. As shown in fig. 2 and 3, the outdoor temperature sensor 71 collects a first outdoor ambient temperature T_out1The low pressure sensor 72 transmits the low pressure P of the heat pump system to the central controller 3_s1The refrigerant is fed back to the central controller 3, and can be in a gas-liquid two-phase state under the stop state according to the low-pressure P_s1Calculating to obtain the first low-pressure temperature T of the heat pump system at the moment_s1When the first outdoor ambient temperature T_out1First low-pressure temperature T_s1>When the first set temperature is X1, 5 is equal to or less than the first set temperature X1 is equal to or less than 20, it is determined that the pressure difference between the outdoor heat exchanger 61 and the indoor heat exchanger 63 is sufficient to drive the expander 43 to rotate and do work, at this time, the second electromagnetic valve 82 is opened, as shown in fig. 6, the refrigerant enters the expander 43 through the second electromagnetic valve 82 and the second four-way valve 52, so as to drive the generator 42 to generate power, and the power generation of the heat pump system in the shutdown state in hot days in summer (i.e., when the outdoor ambient temperature is higher than the indoor ambient temperature) is realized.

In some embodiments, in the case that the air conditioning system heating operation is stopped in step S130, the opening and closing of the first solenoid valve 81 and the second solenoid valve 82 are controlled, and a specific process of generating power by the generator 42 under the driving of the expander 43 is controlled, as described in the following exemplary description.

The following further describes, with reference to a schematic flow chart of an embodiment of the method of the present invention shown in fig. 10, a specific process of controlling the generator to generate power in the case of the heating operation shutdown in step S130, including: step S310 to step S340.

In step S310, when the air conditioning system is stopped in the heating operation, both the first solenoid valve 81 and the second solenoid valve 82 are controlled to be closed.

Step S320, obtaining the outdoor ambient temperature of the air conditioning system, and recording as a second outdoor ambient temperature. The pressure at the suction port of the compressor 1 is obtained and recorded as the second low pressure.

And step S330, determining the temperature of the air conditioning system according to the second low-pressure, and recording the temperature as the second low-pressure temperature.

In step S340, when the temperature difference between the second low-pressure temperature and the second outdoor environment temperature is greater than a second set temperature, the pressure difference between the refrigerant in the indoor heat exchanger 63 and the refrigerant in the outdoor heat exchanger 61 is sufficient to drive the expander 43, and the second solenoid valve 82 is controlled to open, so that the refrigerant enters the expander 43 through the second solenoid valve 82 and the second four-way valve 52, and drives the generator 42 to generate power.

Fig. 7 is a schematic structural diagram of an embodiment of an expander power generation operation in a heating shutdown of the air source heat pump system. At the time of shutdown of the heating operation, both the first solenoid valve 81 and the second solenoid valve 82 are closed, disconnecting the outdoor heat exchanger 61 from the first four-way valve 51 and the second four-way valve 52. Since the indoor ambient temperature is higher than the outdoor ambient temperature at this time, the pressure of the refrigerant in the indoor heat exchanger 63 will be higher than the pressure of the refrigerant in the outdoor heat exchanger 61 as the heat exchange proceeds sufficiently. As shown in fig. 2 and 3, the outdoor temperature sensor 71 collects the second outdoor ambient temperature T_out2The low pressure sensor 72 transmits the system low pressure P to the central controller 3_s2The refrigerant is fed back to the central controller 3, and can be in a gas-liquid two-phase state under the stop state according to the low-pressure P_s2Calculating to obtain a second low-pressure temperature T of the heat pump system at the moment_s2When the second low-pressure temperature T is reached_s2-a second outdoor ambient temperature T_out2>When the second set temperature X2 is greater than or equal to 5 and less than or equal to 20, it is determined that the pressure difference between the indoor heat exchanger 63 and the outdoor heat exchanger 61 is sufficient to drive the expander 43 to rotate and apply work, at this time, the second electromagnetic valve 82 is opened, as shown in fig. 7, the refrigerant enters the expander 43 through the second electromagnetic valve 82 and the second four-way valve 52, so as to drive the generator 42 to generate power, and the power generation of the heat pump system in the shutdown state on a cold day in winter (i.e., when the outdoor ambient temperature is lower than the indoor ambient temperature) is realized.

In the scheme of the invention, the heat pump system can adopt CO₂As refrigerant and use of CO₂High pressureThe characteristics can improve the driving force of the expander 43, thereby improving the generating capacity, and simultaneously CO₂The natural working medium has good environmental protection characteristic and is one of the ultimate choices of future refrigerants. That is, the present invention employs the expander 43 and CO₂The heat pump system is integrally designed, external industrial waste heat is not required for driving, the refrigeration, heating and power generation functions can be realized simultaneously, the temperature difference of the environment can be utilized to generate power in a shutdown state, the refrigeration and heating functions are realized, the power generation function is realized, and the shutdown power generation function is realized by adopting an environment-friendly refrigerant.

Since the processing and functions implemented by the method of the present embodiment substantially correspond to the embodiments, principles and examples of the air conditioning system, reference may be made to the related descriptions in the foregoing embodiments without being detailed in the description of the present embodiment.

By adopting the technical scheme of the embodiment, CO is adopted₂As the refrigerant of the air conditioning system, an expander (e.g., expander 43) is provided between an outdoor heat exchanger (e.g., outdoor heat exchanger 61) and an indoor heat exchanger (e.g., indoor heat exchanger 63) of the air conditioning system, a first solenoid valve (e.g. a first solenoid valve 81) and a first four-way valve (e.g. a first four-way valve 51) are provided on a pipeline between the outdoor heat exchanger and the compressor, a second solenoid valve (e.g., second solenoid valve 82) and a second four-way valve (e.g., second four-way valve 52) are provided between the outdoor heat exchanger and the expander, by controlling the switches of the first electromagnetic valve and the second electromagnetic valve, the control of the air conditioning system is realized, the carbon emission of the heat pump system can be reduced, the refrigeration energy efficiency of the air conditioning system in a high-temperature environment is improved, on one hand, the refrigeration capacity of the heat pump system is improved, meanwhile, the power consumption of refrigeration and heating operation can be reduced, and the power generation and energy storage can be realized by utilizing the indoor and outdoor temperature difference in the shutdown state.

In summary, it is readily understood by those skilled in the art that the advantageous modes described above can be freely combined and superimposed without conflict.

The above description is only an example of the present invention, and is not intended to limit the present invention, and it is obvious to those skilled in the art that various modifications and variations can be made in the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.