CN104764240A - Air conditioning system having defrosting function and control method thereof - Google Patents

Abstract

The invention discloses an air conditioning system with a defrosting function and a control method thereof, comprising an outdoor unit and an indoor unit. The outdoor unit is provided with a main four-way directional valve and a heat storage four-way directional valve. The opening and closing of the four-way reversing valve and heat storage four-way reversing valve and other solenoid valves realizes the simultaneous operation of the parallel heating and defrosting process of the air conditioning system, the single-machine heating and single-unit defrosting operation, and the parallel heating and heat storage operation at the same time conduct. The beneficial effects of the present invention are: the air-conditioning system in the present invention can realize simultaneous operation of parallel heating and defrosting, single-machine heating and single-unit defrosting operation, parallel heating and heat storage simultaneous operation, and when defrosting and heat storage The indoor mechanism heats up and runs without stopping, which can provide users with a better experience and greatly improve the comfort.

Description

An air conditioning system with defrosting function and its control method

technical field

The invention relates to the field of air conditioning system control, and more specifically relates to an air conditioning system with a defrosting function and a control method thereof.

Background technique

Air conditioning is air conditioning, which refers to the process of adjusting and controlling the temperature, humidity, cleanliness, speed and other parameters of the ambient air in the building/structure by artificial means. The structure of the air conditioner mainly includes: compressor, condenser, evaporator, Composed of four-way valve and one-way valve capillary assembly.

In the south, the indoor temperature is low in winter, and it is often necessary to use the air conditioner to heat the indoor air. However, when the air conditioner is heating, when the evaporation temperature drops, the outdoor heat exchanger will be frosted, and the frosting of the outdoor heat exchanger will seriously affect The heating performance of the air conditioner.

The commonly used defrosting systems in the prior art are mainly the hot gas bypass method and the four-way valve reversing method. The basic principle of the hot gas bypass method is to distribute part of the heat-bearing gas discharged from the compressor to the outdoor heat exchanger through a branch circuit for defrosting, but this defrosting method will divert part of the heat generated by the compressor and affect the performance of the air conditioner. Heating performance, and using the hot gas bypass method for defrosting not only takes a long time but also has poor defrosting effect. The basic principle of the four-way valve reversing method is to use the four-way reversing valve to defrost the outdoor heat exchanger and heat the room respectively by switching different channels of the four-way valve. The working condition of the reversing valve changes the air-conditioning system from a heating state to a cooling state, so that continuous heat supply to the room cannot be guaranteed, resulting in reduced comfort and poor user experience.

Contents of the invention

One object of the present invention is to propose an air-conditioning system that can run the heating process and the defrosting process at the same time, and the heating process and the heat storage process can be carried out simultaneously, that is, the heating operation does not stop during the defrosting and heat storage processes .

Another object of the present invention is to propose a control method for an air-conditioning system with a defrosting function, which can realize the simultaneous operation of the heating process and the defrosting process, and the simultaneous operation of the heating process and the heat storage process.

For reaching this purpose, the present invention adopts following technical scheme:

An air conditioning system with a defrosting function, comprising an outdoor unit and an indoor unit, the outdoor unit is provided with a main four-way reversing valve and a heat storage four-way reversing valve;

Port d of the heat storage four-way reversing valve is connected to the outlet of the first compressor, and an outdoor condenser and an outdoor electronic expansion valve are connected in series between ports c and e of the heat storage four-way reversing valve , heat storage electronic expansion valve, phase change heat accumulator, the s port of the heat storage four-way reversing valve is connected in parallel with the s port of the main four-way reversing valve and then connected in series to the inlet of the gas-liquid separator, the The two outlets of the gas-liquid separator are respectively connected to the inlets of the first compressor and the second compressor;

Port d of the main four-way reversing valve is connected to the outlet of the second compressor, and port e of the main four-way reversing valve is connected to one end of the indoor unit through a gas pipe stop valve;

There is also a first branch connected in parallel with the thermal storage electronic expansion valve between the outdoor electronic expansion valve and the thermal storage electronic expansion valve. A cut-off valve, connected to the other end of the indoor unit through the liquid pipe stop valve;

A solenoid valve is connected in parallel between port d of the heat storage four-way reversing valve and port d of the main four-way reversing valve.

Further, a first oil separator and a first one-way valve are sequentially connected between the first compressor and port d of the heat storage four-way reversing valve.

Further, a second oil separator and a second one-way valve are sequentially connected between the second compressor and port d of the main four-way reversing valve.

Further, outdoor one-way valves are connected in parallel at both ends of the outdoor electronic expansion valve.

Further, a capillary is provided between port c and port s of the main four-way reversing valve.

Further, the indoor unit is provided with at least one set of heating branch circuits, and the heating branch circuits include an indoor evaporator and an indoor electronic expansion valve arranged in series.

A control method applied to the above-mentioned air-conditioning system with a defrosting function, comprising:

Parallel heating and defrosting process, including: controlling the main four-way reversing valve to be energized, the thermal storage electronic expansion valve works normally, the indoor electronic expansion valve is opened, the thermal storage four-way reversing valve is not energized, and the outdoor electronic expansion valve is closed ;

The single-machine heating and single-machine defrosting process includes: controlling the main four-way reversing valve to be energized, the thermal storage electronic expansion valve to work normally, the indoor electronic expansion valve to be opened, the thermal storage four-way reversing valve to be de-energized, and the outdoor electronic expansion valve to be turned on. closed, the solenoid valve is closed;

The parallel heating and heat storage operation process includes: controlling the main four-way reversing valve to be energized, the heat storage four-way reversing valve to be energized, the heat storage electronic expansion valve to open, the outdoor electronic expansion valve to work normally, and the indoor electronic expansion valve to open ;

The cooling operation process includes: controlling the opening of the indoor electronic expansion valve, de-energizing the main four-way reversing valve, de-energizing the heat storage four-way reversing valve, closing the heat storage electronic expansion valve, and closing the outdoor electronic expansion valve.

The beneficial effects of the present invention are:

(1) The air conditioning system in the present invention can realize simultaneous operation of parallel heating and defrosting, simultaneous operation of parallel heating and heat storage, and single-machine heating and single-machine defrosting operation. Shutdown operation can provide users with a better experience and greatly improve comfort;

(2) The air-conditioning system in the present invention has fewer pipelines connected to the heat accumulator, which is conducive to modularizing the heat accumulator and effectively reducing the complexity of the system;

(3) The heat accumulator in the present invention is directly connected to the exhaust outlet of the compressor. Since the temperature of the exhaust outlet is higher, there are more types of phase change materials for the heat accumulator to choose from;

(4) In the control method of the present invention, by adjusting the switching states of the double four-way reversing valve and the solenoid valve, etc., it is possible to realize simultaneous operation of parallel heating and defrosting, simultaneous operation of parallel heating and heat storage, and single-machine heating and Stand-alone defrosting operation, which can ensure the internal mechanism heating without stopping during the defrosting operation.

Description of drawings

Fig. 1 is a schematic diagram of refrigerant flow when the air-conditioning system with defrosting function provided by the specific embodiment of the present invention is running in parallel heating and defrosting process;

Fig. 2 is a schematic diagram of refrigerant flow when the air-conditioning system with defrosting function provided by the specific embodiment of the present invention is in the process of single-machine heating and single-unit defrosting;

Fig. 3 is a schematic diagram of refrigerant flow when the air-conditioning system with defrosting function provided by the specific embodiment of the present invention is in parallel heating and heat storage operation;

Fig. 4 is a schematic diagram of refrigerant flow when the air-conditioning system with defrosting function provided by a specific embodiment of the present invention is in cooling operation.

In the picture:

1. The first compressor; 2. The second compressor; 3. The first oil separator; 4. The second oil separator; 5. The heat storage four-way reversing valve; 6. The main four-way reversing valve; 7 , capillary tube; 8. Outdoor condenser; 9. Outdoor electronic expansion valve; 10. Outdoor one-way valve; 11. High pressure liquid receiver; 12. Liquid pipe stop valve; 13. Indoor electronic expansion valve; 14. Indoor evaporator; 15. Tracheal shut-off valve; 16. Gas-liquid separator; 17. Thermal storage electronic expansion valve; 18. Phase change heat accumulator; 19. Solenoid valve; 20. First one-way valve; 21. Second one-way valve; A. Outdoor unit; B. Indoor unit.

Detailed ways

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and through specific implementation methods.

As shown in Figures 1-4, it is an air conditioning system with defrosting function proposed by the present invention, including an outdoor unit A and an indoor unit B. The outdoor unit A is provided with a main four-way reversing valve 6 and heat storage The four-way reversing valve 5; the indoor unit B is provided with at least one set of heating branches, and the heating branches include an indoor evaporator 14 and an indoor electronic expansion valve 13 arranged in series. Wherein, the d port of the heat storage four-way reversing valve 5 is connected to the outlet of the first compressor 1, and the first compressor 1 is connected to the d port of the heat storage four way reversing valve 5 in sequence There is a first oil separator 3 and a first one-way valve 20 . An outdoor condenser 8, an outdoor electronic expansion valve 9, a thermal storage electronic expansion valve 17, and a phase change heat accumulator 18 are sequentially connected in series between the c port and the e port of the heat storage four-way reversing valve 5. An outdoor one-way valve 10 is connected in parallel at both ends of the expansion valve 9 . The s port of the heat storage four-way reversing valve 5 is connected in parallel with the s port of the main four-way reversing valve 6, connected in series to the gas-liquid separator 16, and then connected to the port of the first compressor 1 or the second compressor 2 Inlet; a capillary 7 is provided between port c and port s of the main four-way reversing valve 6 .

The port d of the main four-way reversing valve 6 is connected to the outlet of the second compressor 2, wherein, the second compressor 2 and the port d of the main four-way reversing valve 6 are sequentially connected with The second oil separator 4 and the second one-way valve 21. The e port of the main four-way reversing valve 6 is connected to one end of the indoor unit B through the air pipe stop valve 15; the outdoor electronic expansion valve 9 and the thermal storage electronic expansion valve 17 are also provided with the The first branch connected in parallel with the thermal storage electronic expansion valve 17, the first branch is connected in series with the high-pressure liquid reservoir 11 and the liquid pipe shut-off valve 12, and is connected to the indoor unit through the liquid pipe shut-off valve 12 The other end of B; a solenoid valve 19 is connected in parallel between port d of the heat storage four-way reversing valve 5 and port d of the main four-way reversing valve 6 .

The air conditioning system in the present invention can realize simultaneous operation of parallel heating and defrosting, simultaneous operation of parallel heating and heat storage, single-machine heating and single-machine defrosting operation, and indoor mechanism heating without shutting down during defrosting and heat storage. It can provide users with a better experience of use and greatly improve the comfort; there are fewer pipelines connecting the air conditioning system and the heat accumulator, which is conducive to the modularization of the heat accumulator and effectively reduces the complexity of the system; the heat accumulator and the compression It is directly connected to the exhaust outlet of the machine. Since the temperature of the exhaust outlet is higher, there are more types of phase change materials for the heat accumulator to choose from.

The present invention also proposes a control method applied to the above-mentioned air-conditioning system with defrosting function, including: parallel heating and defrosting process, single-machine heating and single-unit defrosting process, parallel heating and heat storage operation process, cooling operation process.

As shown in Figure 1, during the parallel heating and defrosting process, the main four-way reversing valve 6 is controlled to be energized, the thermal storage electronic expansion valve 17 works normally, the indoor electronic expansion valve 13 is opened, and the thermal storage four-way switching The valve 5 is not energized, and the outdoor electronic expansion valve 9 is closed. At this time, the refrigerant flow in the air conditioning system forms three circuits, one is the defrosting circuit, and the other two are the first parallel heating circuit during the defrosting process and the second parallel heating circuit during the defrosting process.

The defrosting circuit includes: the high-temperature and high-pressure refrigerant coming out of the first compressor 1 passes through the first oil separator 3 and the first one-way valve 20 in sequence, and enters the heat storage four-way through the d port of the heat storage four-way reversing valve 5 The reversing valve 5, and then the refrigerant coming out of the c port of the heat storage four-way reversing valve 5 enters into the The refrigerant coming out of port e of the heat storage four-way reversing valve 5 and the s port of the heat storage four-way reversing valve 5 returns to the first compressor 1 through the gas-liquid separator 16 to complete the defrosting process.

The first parallel heating circuit in the defrosting process includes: the high-temperature and high-pressure refrigerant coming out of the first compressor 1 passes through the first oil separator 3, the first one-way valve 20, and the solenoid valve 19 to enter the main four-way reversing valve. 6, the refrigerant coming out of the e port of the main four-way reversing valve 6 enters the indoor unit B through the gas pipe stop valve 15, passes through the indoor evaporator and the indoor electronic expansion valve 13 for heat exchange, and then passes through the liquid pipe stop valve 12. The high-pressure liquid accumulator 11, thermal storage electronic expansion valve 17, and phase-change heat accumulator 18 enter the e port of the thermal storage four-way reversing valve 5, and the refrigerant coming out of the s port of the thermal storage four-way reversing valve 5 The agent returns to the first compressor 1 after passing through the gas-liquid separator 16.

The second parallel heating circuit in the defrosting process includes: the high-temperature and high-pressure refrigerant coming out of the second compressor 2 sequentially passes through the second oil separator 4 and the second check valve 21 and enters the d port of the main four-way reversing valve 6 , the refrigerant coming out of the e port of the main four-way reversing valve 6 enters the indoor unit B through the air pipe stop valve 15, passes through the indoor evaporator 14, and the indoor electronic expansion valve 13 for heat exchange, then passes through the liquid pipe stop valve 12, high pressure The liquid accumulator 11, heat storage electronic expansion valve 17, and phase change heat accumulator 18 enter the e port of the heat storage four-way reversing valve 5, and the refrigerant coming out of the s port of the heat storage four-way reversing valve 5 passes through the gas After the liquid separator 16 returns to the second compressor 2.

As shown in Figure 2, during the single-machine heating and single-machine defrosting operation, the main four-way reversing valve 6 is controlled to be energized, the heat storage electronic expansion valve 17 works normally, the indoor electronic expansion valve 13 is opened, and the heat storage four-way The reversing valve 5 is not energized, the outdoor electronic expansion valve 9 is closed, and the solenoid valve 19 is closed. At this time, the refrigerant flow direction in the air conditioning system forms two circuits, one is a single-unit defrosting circuit, and the other is a single-machine heating circuit.

The stand-alone defrosting circuit includes: the high-temperature and high-pressure refrigerant coming out of the first compressor 1 passes through the first oil separator 3 and the first one-way valve 20 through the d port of the heat storage four-way reversing valve 5 and enters the heat storage In the four-way reversing valve 5, and go out from the c port through the outdoor condenser 8, the outdoor one-way valve 10, the heat storage electronic expansion valve 17, the phase change heat accumulator 18, and the e of the heat storage four-way reversing valve 5 port, the s port of the heat storage four-way reversing valve 5, and the gas-liquid separator 16 return to the first compressor 1.

The single-machine heating circuit includes: the high-temperature and high-pressure refrigerant coming out of the second compressor 2 passes through the second oil separator 4, the second check valve 21 enters the main four-way reversing valve 6 from port d, and flows from the main four-way reversing valve. The refrigerant coming out of port e of the reversing valve 6 enters the indoor evaporator 14 and the indoor electronic expansion valve 13 of the indoor unit B through the air pipe stop valve 15 for heat exchange, and returns to the outdoor unit through the liquid pipe stop valve 12 In A, the refrigerant then passes through the high-pressure accumulator 11, the heat storage electronic expansion valve 17, the phase change heat accumulator 18, the e port of the heat storage four-way reversing valve 5, and the heat storage four-way reversing valve 5 in sequence. port s, the gas-liquid separator 16 returns to the second compressor 2 .

As shown in Figure 3, during the parallel heating and heat storage process, the main four-way reversing valve 6 is controlled to be energized, the heat storage four-way reversing valve 5 is energized, the heat storage electronic expansion valve 17 is opened, and the outdoor electronic expansion The valve 9 works normally, and the indoor electronic expansion valve 13 is opened. At this time, the flow direction of the refrigerant in the air conditioning system forms three circuits, one is the heat storage circuit, and the other two are the first parallel heating circuit in the heat storage process and the second parallel heating circuit in the heat storage process.

The heat storage circuit includes: the high temperature and high pressure refrigerant coming out of the first compressor 1 passes through the first oil separator 3, the first check valve 20, the d port of the heat storage four-way reversing valve 5, the heat storage four-way switch The port e of the valve 5 reaches the phase change heat accumulator 18 for heat storage, and then passes through the heat storage electronic expansion valve 17, the outdoor electronic expansion valve 9, the outdoor condenser 8, the c port of the heat storage four-way reversing valve 5, The s port of the heat storage four-way reversing valve 5 and the gas-liquid separator 16 return to the first compressor 1 .

The first parallel heating circuit in the heat storage process includes: the high-temperature and high-pressure refrigerant coming out of the first compressor 1 passes through the first oil separator 3, the first check valve 20, the solenoid valve 19, and the main four-way reversing valve 6 port d of the main four-way reversing valve 6, and the air pipe cut-off valve 15 enter the indoor evaporator 14 and the indoor electronic expansion valve 13 of the indoor unit B for heat exchange, and then pass through the liquid pipe stop valve 12, high-pressure storage Liquid container 11, outdoor electronic expansion valve 9, outdoor condenser 8, port c of heat storage four-way reversing valve 5, port s of heat storage four-way reversing valve 5, gas-liquid separator 16 return to the first compressor 1 in.

The second parallel heating circuit in the heat storage process includes: the high-temperature and high-pressure refrigerant coming out of the second compressor 2 passes through the second oil separator 4, the second one-way valve 21, and the d port of the main four-way reversing valve 6 in sequence , the e port of the main four-way reversing valve 6, and the air pipe shut-off valve 15 enter the indoor evaporator 14 and the indoor electronic expansion valve 13 of the indoor unit B for heat exchange, and then pass through the liquid pipe shut-off valve 12, high-pressure liquid reservoir 11, The outdoor electronic expansion valve 9, the outdoor condenser 8, the c port of the heat storage four-way reversing valve 5, the s port of the heat storage four-way reversing valve 5, and the gas-liquid separator 16 return to the second compressor 2.

As shown in Figure 4, during the refrigeration process, the indoor electronic expansion valve 13 is controlled to open, the main four-way reversing valve 6 is not energized, the heat storage four-way reversing valve 5 is not energized, and the heat storage electronic expansion valve 17 is closed , the outdoor electronic expansion valve 17 is closed. At this time, the refrigerant flows in the air conditioning system to form three refrigeration circuits.

The first refrigeration circuit includes: the high-temperature and high-pressure refrigerant coming out of the first compressor 1 passes through the first oil separator 3, the first one-way valve 20, the d port of the heat storage four-way reversing valve 5, and the heat storage four-way reversing valve. Port c of reversing valve 5, outdoor condenser 8, outdoor one-way valve 10, high-pressure liquid receiver 11, liquid pipe stop valve 12, indoor electronic expansion valve 13, indoor evaporator 14, air pipe stop valve 15, main four The e port of the reversing valve 6, the s port of the main four-way reversing valve 6, and the gas-liquid separator 16 return to the first compressor 1.

The second refrigeration circuit includes: the high-temperature and high-pressure refrigerant coming out of the second compressor 2 passes through the second oil separator 4, the second one-way valve 21, the solenoid valve 19, and the d port of the heat storage four-way reversing valve 5 in sequence , port c of heat storage four-way reversing valve 5, outdoor condenser 8, outdoor one-way valve 10, high-pressure liquid receiver 11, liquid pipe stop valve 12, indoor electronic expansion valve 13, indoor evaporator 14, air pipe stop valve 15. Port e of the main four-way reversing valve 6, port s of the main four-way reversing valve 6, and the gas-liquid separator 16 return to the second compressor 2.

The third refrigeration circuit includes: the high-temperature and high-pressure refrigerant coming out of the second compressor 2 passes through the second oil separator 4, the second check valve 21, the d port of the main four-way reversing valve 6, and the main four-way reversing valve. Return to the second compressor 2 to the c port of the valve 6, the capillary 7, and the gas-liquid separator 16.

Using the air-conditioning control method in the present invention, by adjusting the switching states of the double four-way reversing valve and the solenoid valve, etc., it is possible to realize the simultaneous operation of parallel heating and defrosting, the simultaneous operation of parallel heating and heat storage, and the simultaneous operation of single-machine heating and single-machine heating. Defrost operation, to ensure that the internal mechanism heating does not stop during the defrost operation.

The above describes the technical principles of the present invention in conjunction with specific embodiments. These descriptions are only for explaining the principles of the present invention, and cannot be construed as limiting the protection scope of the present invention in any way. Based on the explanations herein, those skilled in the art can think of other specific implementation modes of the present invention without creative efforts, and these modes will all fall within the protection scope of the present invention.

Claims (7)

1. An air-conditioning system with defrosting function, comprising an outdoor unit (A) and an indoor unit (B), characterized in that the outdoor unit (A) is equipped with a main four-way reversing valve (6) and an accumulator Hot four-way reversing valve (5); Port d of the heat storage four-way reversing valve (5) is connected to the outlet of the first compressor (1), and ports c and e of the heat storage four-way reversing valve (5) are sequentially connected in series There are outdoor condenser (8), outdoor electronic expansion valve (9), heat storage electronic expansion valve (17), phase change heat accumulator (18), the s port of the heat storage four-way reversing valve (5) is connected with The port s of the main four-way reversing valve (6) is connected in parallel to the inlet of the gas-liquid separator (16), and the two outlets of the gas-liquid separator (16) are respectively connected to the first compressor (1 ) and the inlet of the second compressor (2); Port d of the main four-way reversing valve (6) is connected to the outlet of the second compressor (2), and port e of the main four-way reversing valve (6) is connected to the One end of the indoor unit (B); A first branch circuit connected in parallel with the thermal storage electronic expansion valve (17) is also provided between the outdoor electronic expansion valve (9) and the thermal storage electronic expansion valve (17), and the first branch circuit in turn A high-pressure liquid reservoir (11) and a liquid pipe shut-off valve (12) are connected in series, and connected to the other end of the indoor unit (B) through the liquid pipe shut-off valve (12); A solenoid valve (19) is connected in parallel between port d of the heat storage four-way reversing valve (5) and port d of the main four-way reversing valve (6). 2. The air conditioning system with defrosting function according to claim 1, characterized in that, between the first compressor (1) and port d of the heat storage four-way reversing valve (5) The first oil separator (3) and the first one-way valve (20) are connected in sequence. 3. The air-conditioning system with defrosting function according to claim 2, characterized in that the connection between the second compressor (2) and the port d of the main four-way reversing valve (6) is in sequence A second oil separator (4) and a second one-way valve (21) are connected. 4. The air-conditioning system with defrosting function according to claim 3, characterized in that an outdoor one-way valve (10) is connected in parallel at both ends of the outdoor electronic expansion valve (9). 5 . The air conditioning system with defrosting function according to claim 4 , characterized in that a capillary ( 7 ) is arranged between port c and port s of the main four-way reversing valve ( 6 ). 6. The air-conditioning system with defrosting function according to claim 5, characterized in that at least one set of heating branches are arranged in the indoor unit (B), and the heating branches include series arrangement indoor evaporator (14) and indoor electronic expansion valve (13). 7. A control method applied to an air-conditioning system with a defrosting function as claimed in claim 6, characterized in that it comprises: The parallel heating and defrosting process includes: controlling the main four-way reversing valve (6) to be energized, the heat storage electronic expansion valve (17) to work normally, the indoor electronic expansion valve (13) to open, and the heat storage four-way reversing The valve (5) is not powered, and the outdoor electronic expansion valve (9) is closed; The single-machine heating and single-machine defrosting process includes: controlling the main four-way reversing valve (6) to be energized, the thermal storage electronic expansion valve (17) to work normally, the indoor electronic expansion valve (13) to open, and the thermal storage four-way switching The pilot valve (5) is not energized, the outdoor electronic expansion valve (9) is closed, and the solenoid valve (19) is closed; The parallel heating and heat storage operation process includes: controlling the main four-way reversing valve (6) to be energized, the heat storage four-way reversing valve (5) to be energized, the heat storage electronic expansion valve (17) to be opened, and the outdoor electronic expansion valve (17) to be opened. The valve (9) works normally, and the indoor electronic expansion valve (13) is opened; The refrigeration operation process includes: controlling the opening of the indoor electronic expansion valve (13), de-energizing the main four-way reversing valve (6), de-energizing the heat-storage four-way reversing valve (5), and de-energizing the heat-storage electronic expansion valve (17 ) is closed, and the outdoor electronic expansion valve (17) is closed.