Double-head four-stage magnetic suspension air energy heat pump cold and hot water unit and working method

Abstract

The application discloses a double-head four-stage magnetic suspension air energy heat pump cold and hot water unit, which comprises low-temperature stage magnetic suspension two-stage compressors, high-temperature stage magnetic suspension two-stage compressors and a plurality of medium heat exchange assemblies. The inlet end of the first one-way valve and the outlet end of the second one-way valve of the one-way valve pipe group of each medium heat exchange assembly are connected with the outlet end of the corresponding condenser in communication, the inlet end of the second one-way valve and the inlet end of the third one-way valve are connected with the outlet end of the corresponding first main electronic expansion valve and second main electronic expansion valve in communication, the outlet end of the third one-way valve and the inlet end of the fourth one-way valve are connected with the inlet end of the corresponding fin evaporator in communication, and the outlet end of the first one-way valve and the outlet end of the fourth one-way valve are connected with the inlet end of the corresponding first main electronic expansion valve and second main electronic expansion valve in communication. The application has the advantages of reducing pressure ratio, being stable, energy-saving, high-energy-efficient, low-failure and accurate throttling.

Description

TECHNICAL FIELD

[0001] The application relates to the field of magnetic suspension air energy heat pumps, in particular to a working method of a double-head four-stage magnetic suspension air energy heat pump cold and hot water unit. BACKGROUND

[0002] At present, a single double-stage magnetic suspension compressor is used for an air energy (air-cooled) heat pump, but the pressure ratio of the magnetic suspension compressor is too large when the magnetic suspension compressor is operated at a low ambient temperature and a high water temperature, so that the magnetic suspension compressor is prone to surge, and therefore the existing technology cannot be used for a magnetic suspension air energy (air-cooled) heat pump. SUMMARY

[0003] The application aims to provide a double-head four-stage magnetic suspension air energy heat pump cold and hot water unit and a working method, which have the advantages of reduced pressure ratio, stability, energy saving, high energy efficiency, low failure, accurate throttling, stable heating water temperature without shutdown for defrosting of heating grouping, and only one compressor operated for refrigeration.

[0004] The above technical purpose of the application is achieved by the following technical scheme.

[0005] The double-head four-stage magnetic suspension air energy heat pump cold and hot water unit comprises a low-temperature-stage magnetic suspension double-stage compressor, a high-temperature-stage magnetic suspension double-stage compressor and a plurality of medium heat exchange assemblies.

[0006] The outlet end of the low-temperature-stage magnetic suspension double-stage compressor is connected to the inlet end of the high-temperature-stage magnetic suspension double-stage compressor, and a one-way valve is arranged at the connection position, the inlet end of the one-way valve is connected to the outlet end of the low-temperature-stage magnetic suspension double-stage compressor, and the outlet end of the one-way valve is connected to the inlet end of the high-temperature-stage magnetic suspension double-stage compressor.

[0007] Each group of medium heat exchange assemblies comprises a condenser, a one-way valve pipe group, a first main electronic expansion valve, a second main electronic expansion valve and a fin evaporator, the first main electronic expansion valve and the second main electronic expansion valve are arranged in parallel, the one-way valve pipe group comprises a first one-way valve, a second one-way valve, a third one-way valve and a fourth one-way valve, the inlet end of the first one-way valve and the outlet end of the second one-way valve are connected to the first outlet end of the corresponding condenser, the inlet end of the second one-way valve and the inlet end of the third one-way valve are connected to the outlet ends of the corresponding first main electronic expansion valve and second main electronic expansion valve, the outlet end of the third one-way valve and the inlet end of the fourth one-way valve are connected to the inlet end of the corresponding fin evaporator, and the outlet end of the first one-way valve and the outlet end of the fourth one-way valve are connected to the inlet ends of the corresponding first main electronic expansion valve and second main electronic expansion valve.

[0008] Each of the outlet ends of the finned evaporators is provided with a four-way valve, the outlet end of each of the finned evaporators is communicated with the second outlet end of its corresponding four-way valve, the first inlet end of each of the condensers is communicated with the first outlet end of its corresponding four-way valve, the second inlet ends of the four-way valves are communicated, and a gas-liquid separator is arranged at the communication position, the outlet end of the gas-liquid separator is respectively communicated with the inlet end of the high-temperature stage magnetic suspension two-stage compressor and the inlet end of the low-temperature stage magnetic suspension two-stage compressor, a second one-way valve is arranged between the outlet end of the gas-liquid separator and the inlet end of the high-temperature stage magnetic suspension two-stage compressor, the outlet end of the first one-way valve is communicated with the outlet end of the second one-way valve and the inlet end of the high-temperature stage magnetic suspension two-stage compressor, and the outlet end of the high-temperature stage magnetic suspension two-stage compressor is respectively communicated with the first inlet end of the four-way valve.

[0009] The second inlet and the second outlet of the condenser are provided with two water route medium pipelines.

[0010] The preferred scheme is as follows:

[0011] Preferably, the plate-type economic heat exchanger, the enthalpy-increasing electronic expansion valve, the first three-way valve and the second three-way valve are further included.

[0012] The outlet end of each of the first one-way valves, the outlet end of the fourth one-way valve, the inlet end of the first main electronic expansion valve and the inlet end of the second main electronic expansion valve are communicated with the first port of the first three-way valve, the second port of the first three-way valve is communicated with the motor cooling and driving cooling port of the high-temperature stage magnetic suspension two-stage compressor, the third port of the first three-way valve is communicated with the first port of the second three-way valve, the second port of the second three-way valve is communicated with the first inlet end of the plate-type economic heat exchanger, the first outlet end of the plate-type economic heat exchanger is communicated with the inlet end of the enthalpy-increasing electronic expansion valve, the outlet end of the enthalpy-increasing electronic expansion valve is communicated with the second inlet end of the plate-type economic heat exchanger, and the second outlet end of the plate-type economic heat exchanger is communicated with the enthalpy-increasing port of the low-temperature stage magnetic suspension two-stage compressor.

[0013] The third port of the first three-way valve is additionally provided with the second three-way valve at the communication position with the first inlet end of the plate-type economic heat exchanger, and the second three-way valve is communicated with the motor cooling and driving cooling port of the low-temperature stage magnetic suspension two-stage compressor.

[0014] Preferably, the inlet end of the gas-liquid separator and the outlet end of the high-temperature stage magnetic suspension two-stage compressor are provided with an auxiliary electronic expansion valve, the inlet of the auxiliary electronic expansion valve is communicated with the first inlet end of the four-way valve, and the outlet of the auxiliary electronic expansion valve is communicated with the inlet end of the gas-liquid separator.

[0015] A working method of a double-head four-stage magnetic suspension air energy heat pump cold and hot water unit,

[0016] The working method includes a heating mode, a cooling mode, a defrosting mode and a temperature reduction mode.

[0017] Heating mode:

[0018] Step one: low-temperature stage magnetic suspension double-stage compressor, high-temperature stage magnetic suspension double-stage compressor work, the refrigerant heat medium flow in the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system;

[0019] Step two: the medium-temperature and medium-pressure liquid refrigerant enters the first one-way valve from the condenser, and the medium-temperature and medium-pressure refrigerant enters the first main electronic expansion valve and the second main electronic expansion valve through the first one-way valve, respectively, the first main electronic expansion valve and the second main electronic expansion valve throttle, depressurize and cool the refrigerant, and then the low-temperature and low-pressure gaseous refrigerant formed enters the third one-way valve;

[0020] The low-temperature and low-pressure gaseous refrigerant entering the third one-way valve enters the finned evaporator, and the low-temperature and low-pressure gaseous refrigerant enters the finned evaporator and exchanges heat with air to evaporate to form medium-temperature and medium-pressure gaseous refrigerant;

[0021] Step three: the medium-temperature and medium-pressure gaseous refrigerant formed by the finned evaporators of the plurality of medium-temperature and medium-pressure gaseous refrigerant heat exchange assemblies enters the second outlet end of the corresponding four-way valve, then enters the gas-liquid separator inlet end from the second inlet end of the plurality of four-way valves, and finally enters the low-temperature stage magnetic suspension double-stage compressor for compression from the outlet end of the gas-liquid separator, the low-temperature and low-pressure gaseous refrigerant enters the low-temperature stage magnetic suspension double-stage compressor to form high-temperature and high-pressure gaseous refrigerant, and then the high-temperature and high-pressure gaseous refrigerant enters the high-temperature stage magnetic suspension double-stage compressor through the first one-way valve to form super-high-temperature and high-pressure gaseous refrigerant, at this time the high-temperature and high-pressure gaseous refrigerant resists the second one-way valve;

[0022] Step four: the super-high-temperature and high-pressure gaseous refrigerant enters the first inlet end of the plurality of four-way valves, and then enters the corresponding condenser through the first outlet end of the plurality of four-way valves to exchange heat with the water medium in the condenser, forming medium-temperature and medium-pressure refrigerant, and the water medium after heat exchange in the condenser enters the indoor unit through the water medium pipeline;

[0023] Step five: repeat steps two, three and four;

[0024] Cooling and defrosting mode:

[0025] Step one: the high-temperature stage magnetic suspension double-stage compressor works, and the heat exchange medium flows in the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system;

[0026] Step two: the high-temperature and high-pressure gaseous refrigerant in the high-temperature stage magnetic suspension double-stage compressor enters the first inlet end of the plurality of four-way valves, and enters the plurality of finned evaporators through the second outlet end of the plurality of four-way valves to exchange heat with air, depressurize and cool, forming medium-temperature and medium-pressure liquid refrigerant;

[0027] The medium-temperature medium-pressure liquid refrigerant enters the fourth one-way valve, passes through the fourth one-way valve to the first main electronic expansion valve and the second main electronic expansion valve, the first main electronic expansion valve and the second main electronic expansion valve throttle, depressurize and cool the refrigerant, and become low-temperature low-pressure gaseous refrigerant, and then the low-temperature low-pressure gaseous refrigerant enters the second one-way valve;

[0028] Step three: The low-temperature low-pressure gaseous refrigerant enters the corresponding condenser through the second one-way valve and exchanges heat with the water medium in the condenser, evaporates into medium-temperature medium-pressure gaseous refrigerant, and then enters the first outlet end of the four-way valve from the condenser, enters the second inlet end of the four-way valve from the first outlet end of the four-way valve, and finally enters the second one-way valve from the outlet end of the gas-liquid separator, while resisting the first one-way valve, so that the medium-temperature medium-pressure gaseous refrigerant does not enter the low-temperature level magnetic suspension double-stage compressor, and then enters the high-temperature level magnetic suspension double-stage compressor from the second one-way valve, and is compressed, and the medium-temperature medium-pressure gaseous refrigerant enters the high-temperature level magnetic suspension double-stage compressor to form high-temperature high-pressure gaseous refrigerant after compression;

[0029] Step four: Repeat steps two to three;

[0030] Defrosting mode:

[0031] When the following conditions are met simultaneously: ambient temperature ≤ set defrosting ring temperature; double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system cumulative running time ≥ set defrosting interval time, ambient temperature - return air temperature ≥ set ambient temperature - return air temperature, and the duration ≥ 3 minutes, at this time, the low-temperature level magnetic suspension double-stage compressor and the medium heat exchange assembly enter defrosting;

[0032] Only the same two groups of medium heat exchange assemblies in a number of medium heat exchange assemblies are allowed to defrost at the same time, and the other medium heat exchange assemblies continue to work, and when the two groups of medium heat exchange assemblies are defrosted, they start to enter normal work, and the other two groups of medium heat exchange assemblies in the same group can enter defrosting, and the other systems continue to work;

[0033] Low-temperature level magnetic suspension double-stage compressor enthalpy increase and cooling mode:

[0034] The medium-temperature medium-pressure liquid refrigerant enters the plate-type economic heat exchanger through the second three-way, and then enters the enthalpy increase electronic expansion valve for throttling, and the low-temperature low-pressure liquid refrigerant after throttling enters the plate-type economic heat exchanger again to evaporate into medium-temperature medium-pressure gaseous refrigerant, and then enters the enthalpy increase port of the low-temperature level magnetic suspension double-stage compressor; The medium-temperature medium-pressure liquid refrigerant enters the motor cooling and driving cooling port of the low-temperature level magnetic suspension double-stage compressor through the third port of the second three-way at the same time

[0035] High-temperature level magnetic suspension double-stage compressor cooling mode:

[0036] The medium-temperature and medium-pressure refrigerant enters the motor cooling and driving cooling port of the high-temperature stage magnetic suspension double-stage compressor from the first three-way.

[0037] In summary, the present application has the following beneficial effects:

[0038] 1. By the series connection of the low-temperature stage magnetic suspension double-stage compressor and the high-temperature stage magnetic suspension double-stage compressor, the four-stage compression of the magnetic suspension double-stage compressor can be realized during heating, and the magnetic suspension double-stage compressor is in a more stable and energy-saving working state;

[0039] 2. By the arrangement of the plurality of medium heat exchange assemblies, the throttling is more accurate, the energy-saving effect is better, the defrosting is independent, and the heating water temperature is more stable;

[0040] 3. By the arrangement of the auxiliary road electronic expansion valve, the low-temperature stage magnetic suspension double-stage compressor and the high-temperature stage magnetic suspension double-stage compressor can be prevented from surging when starting.

[0041] 4. By the arrangement of the enthalpy increasing electronic expansion valve, the heating capacity is higher at a lower ambient temperature during heating, and the operation is more stable. During refrigeration, the refrigerating capacity is higher at a high ambient temperature, and the high pressure is more stable during operation. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 is a frame schematic diagram of example one;

[0043] Figure 2 is a frame schematic diagram of the heating mode of example one;

[0044] Figure 3 is a frame schematic diagram of the refrigeration mode of example one;

[0045] Figure 4 is a frame schematic diagram of the one-way valve group of example one and example two;

[0046] Figure 5 is a frame schematic diagram of example two;

[0047] Figure 6 is a frame schematic diagram of the heating mode of example two;

[0048] Figure 7 is a frame schematic diagram of the refrigeration mode of example two;

[0049] Figure 8 is a frame schematic diagram of example three;

[0050] Figure 9 is a frame schematic diagram of the heating mode of example three;

[0051] Figure 10 is a frame diagram of the refrigeration mode of embodiment three.

[0052] In the figure, 1 is a low-temperature stage magnetic suspension two-stage compressor; 2 is a high-temperature stage magnetic suspension two-stage compressor; 3 is a medium heat exchange assembly; 4 is a first one-way valve; 5 is a condenser; 6 is a one-way valve pipe group; 7 is a first main electronic expansion valve; 8 is a second main electronic expansion valve; 9 is a fin evaporator; 10 is a first one-way valve; 11 is a second one-way valve; 12 is a third one-way valve; 13 is a fourth one-way valve; 14 is a four-way valve; 15 is a gas-liquid separator; 16 is a second one-way valve; 17 is a water route medium pipeline; 18 is a plate-type economic heat exchanger; 19 is an enthalpy-increasing electronic expansion valve; 20 is a first three-way valve; 21 is a second three-way valve; 22 is an auxiliary route electronic expansion valve; 23 is a shell-and-tube heat exchanger; and 24 is a third three-way valve. DETAILED DESCRIPTION

[0053] The application will be further described in detail below with reference to the accompanying drawings.

[0054] Embodiment one:

[0055] As shown in Figures 1-4 ,

[0056] The double-head four-stage magnetic suspension air energy heat pump cold and hot water unit comprises a low-temperature stage magnetic suspension two-stage compressor 1, a high-temperature stage magnetic suspension two-stage compressor 2, a plurality of medium heat exchange assemblies 3, a plate-type economic heat exchanger 18, an enthalpy-increasing electronic expansion valve 19, a first three-way valve 20, and a second three-way valve 21.

[0057] The outlet end of the low-temperature stage magnetic suspension two-stage compressor 1 is in communication with the inlet end of the high-temperature stage magnetic suspension two-stage compressor 2, and a first one-way valve 4 is arranged at the communication position. The inlet end of the first one-way valve 4 is in communication with the outlet end of the low-temperature stage magnetic suspension two-stage compressor 1, and the outlet end of the first one-way valve 4 is in communication with the inlet end of the high-temperature stage magnetic suspension two-stage compressor 2.

[0058] Each group of medium heat exchange assembly 3 includes condenser 5, one-way valve pipe group 6, first main electronic expansion valve 7, second main electronic expansion valve 8, finned evaporator 9, first main electronic expansion valve 7, second main electronic expansion valve 8 are placed in parallel, one-way valve pipe group 6 includes first one-way valve 10, second one-way valve 11, third one-way valve 12, fourth one-way valve 13; The inlet end of first one-way valve 10, the outlet end of second one-way valve 11 are all communicated with the first outlet end of its corresponding condenser 5, the inlet end of second one-way valve 11, the inlet end of third one-way valve 12 are all communicated with the outlet end of its corresponding first main electronic expansion valve 7, second main electronic expansion valve 8, the outlet end of third one-way valve 12, the inlet end of fourth one-way valve 13 are all communicated with the inlet end of its corresponding finned evaporator 9, the outlet end of first one-way valve 10, the outlet end of fourth one-way valve 13 are all communicated with the inlet end of its corresponding first main electronic expansion valve 7, second main electronic expansion valve 8;

[0059] The outlet end of each finned evaporator 9 is provided with four-way valve 14, the outlet end of each finned evaporator 9 is communicated with the second outlet end of its corresponding four-way valve 14, the first inlet end of each condenser 5 is communicated with the first outlet end of its corresponding four-way valve 14, the second inlet end of several four-way valves 14 is communicated and the communicated place is provided with gas-liquid separator 15, the outlet end of gas-liquid separator 15 is respectively communicated with the inlet end of high-temperature level magnetic suspension double-stage compressor 2 and the inlet end of low-temperature level magnetic suspension double-stage compressor 1, the communicated place between the outlet end of gas-liquid separator 15 and the inlet end of high-temperature level magnetic suspension double-stage compressor 2 is provided with second one-way valve 16, the outlet end of first one-way valve 4 is communicated with the outlet end of second one-way valve 16 and the inlet end of high-temperature level magnetic suspension double-stage compressor 2, the outlet end of high-temperature level magnetic suspension double-stage compressor 2 is respectively communicated with the first inlet end of several four-way valves 14;

[0060] The second inlet and the second outlet of several condensers 5 are provided with two water route medium pipes 17.

[0061] The communicated place of the outlet end of each first one-way valve 10, the outlet end of fourth one-way valve 13, the inlet end of first main electronic expansion valve 7, the inlet end of second main electronic expansion valve 8 is communicated with the first port of first three-way pipe 20, the second port of first three-way pipe 20 is communicated with the motor cooling and driving cooling port of high-temperature level magnetic suspension double-stage compressor 2, the third port of first three-way pipe 20 is communicated with the first port of second three-way pipe 21, the second port of second three-way pipe 21 is communicated with the first inlet end of plate type economic heat exchanger 18, the first outlet end of plate type economic heat exchanger 18 is communicated with the inlet end of enthalpy-increasing electronic expansion valve 19, the outlet end of enthalpy-increasing electronic expansion valve 19 is communicated with the second inlet end of plate type economic heat exchanger 18, the second outlet end of plate type economic heat exchanger 18 is communicated with the enthalpy-increasing port of low-temperature level magnetic suspension double-stage compressor 1;

[0062] The third port of the first three-way pipe 20 is additionally provided with a second three-way pipe 21 at the position where the first inlet end of the plate-type economic heat exchanger 18 is communicated, and the second three-way pipe 21 is communicated with the motor cooling and driving cooling port of the low-temperature stage magnetic suspension double-stage compressor 1.

[0063] The auxiliary road electronic expansion valve 22 is arranged between the inlet end of the gas-liquid separator 15 and the outlet end of the high-temperature stage magnetic suspension double-stage compressor 2, the inlet of the auxiliary road electronic expansion valve 22 is communicated with the first inlet end of the plurality of four-way valves 14, and the outlet of the auxiliary road electronic expansion valve 22 is communicated with the inlet end of the gas-liquid separator 15.

[0064] Working method of double-machine-head four-stage magnetic suspension air energy heat pump cold and hot water unit,

[0065] The working method comprises a heating mode, a cooling mode, a defrosting mode and a temperature reduction mode.

[0066] Heating mode:

[0067] Step one: the low-temperature stage magnetic suspension double-stage compressor 1 and the high-temperature stage magnetic suspension double-stage compressor 2 work, and the refrigerant heat exchange medium in the double-machine-head four-stage magnetic suspension air energy heat pump cold and hot water unit system flows;

[0068] Step two: the medium-temperature medium-pressure liquid refrigerant enters the first one-way valve 10 from the condenser 5, the medium-temperature medium-pressure refrigerant enters the first main electronic expansion valve 7 and the second main electronic expansion valve 8 through the first one-way valve 10, respectively, the first main electronic expansion valve 7 and the second main electronic expansion valve 8 throttle, depressurize and cool the refrigerant, and then the low-temperature low-pressure gaseous refrigerant enters the third one-way valve 12;

[0069] The low-temperature low-pressure gaseous refrigerant entering the third one-way valve 12 enters the finned evaporator 9, and the low-temperature low-pressure gaseous refrigerant evaporates after heat exchange with air in the finned evaporator 9 to form medium-temperature medium-pressure gaseous refrigerant;

[0070] Step three: the medium-temperature medium-pressure gaseous refrigerant formed by the finned evaporator 9 of the plurality of medium-temperature medium-pressure gaseous refrigerant heat exchange assemblies 3 enters the second outlet end of the corresponding four-way valve 14, then enters the inlet end of the gas-liquid separator 15 from the second inlet end of the plurality of four-way valves 14, and finally enters the low-temperature stage magnetic suspension double-stage compressor 1 for compression from the outlet end of the gas-liquid separator 15, the low-temperature low-pressure gaseous refrigerant enters the low-temperature stage magnetic suspension double-stage compressor 1 to form high-temperature high-pressure gaseous refrigerant, and then the high-temperature high-pressure gaseous refrigerant enters the high-temperature stage magnetic suspension double-stage compressor 2 through the first one-way valve 4 to form super-high-temperature high-pressure gaseous refrigerant, at this time, the high-temperature high-pressure gaseous refrigerant resists the second one-way valve 16;

[0071] Step four: the high-temperature and high-pressure gaseous refrigerant enters the first inlet end of the plurality of four-way valves 14, and then enters the corresponding condenser 5 through the first outlet end of the plurality of four-way valves 14, exchanges heat with the water medium in the condenser 5, and forms a medium-temperature and medium-pressure refrigerant. The water medium after heat exchange in the condenser 5 enters the indoor unit for heat exchange through the water medium pipeline 17;

[0072] Step five: repeat steps two, three, and four;

[0073] Refrigeration and defrosting mode:

[0074] Step one: the high-temperature stage magnetic suspension double-stage compressor 2 works, and the heat exchange medium in the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system flows;

[0075] Step two: the high-temperature and high-pressure gaseous refrigerant in the high-temperature stage magnetic suspension double-stage compressor 2 enters the first inlet end of the plurality of four-way valves 14, and then enters the plurality of finned evaporators 9 through the second outlet end of the plurality of four-way valves 14 to exchange heat with air and reduce pressure and temperature, forming a medium-temperature and medium-pressure liquid refrigerant;

[0076] The medium-temperature and medium-pressure liquid refrigerant enters the fourth one-way valve 13, and then enters the first main electronic expansion valve 7 and the second main electronic expansion valve 8 through the fourth one-way valve 13. The first main electronic expansion valve 7 and the second main electronic expansion valve 8 throttle, depressurize, and cool the refrigerant to become a low-temperature and low-pressure gaseous refrigerant, which then enters the second one-way valve 11;

[0077] Step three: the low-temperature and low-pressure gaseous refrigerant enters the corresponding condenser 5 through the second one-way valve 11 and exchanges heat with the water medium in the condenser 5, and then evaporates into a medium-temperature and medium-pressure gaseous refrigerant. The medium-temperature and medium-pressure gaseous refrigerant enters the first outlet end of the corresponding four-way valve 14 from the condenser 5, enters from the first outlet end of the four-way valve 14, then enters the gas-liquid separator 15 from the second inlet end, and finally enters the second one-way valve 16 from the outlet end of the gas-liquid separator 15. The low-temperature stage magnetic suspension double-stage compressor 1 inlet is closed, the medium-temperature and medium-pressure gaseous refrigerant enters the high-temperature stage magnetic suspension double-stage compressor 2 for compression, and the medium-temperature and medium-pressure gaseous refrigerant forms a high-temperature and high-pressure gaseous refrigerant after compression in the high-temperature stage magnetic suspension double-stage compressor 2;

[0078] Step four: repeat steps two to three;

[0079] Defrosting mode:

[0080] When the following conditions are met simultaneously: ambient temperature ≤ set entering defrosting ring temperature; double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system cumulative running time ≥ set entering defrosting interval time, ambient temperature - return air temperature ≥ set ambient temperature - return air temperature, and the duration ≥ 3 minutes, at this time, the low-temperature stage magnetic suspension two-stage compressor 1 and the medium heat exchange assembly 3 enter defrosting;

[0081] Only two groups of medium heat exchange assemblies 3 in the same group of several medium heat exchange assemblies 3 are allowed to defrost at the same time, and the other medium heat exchange assemblies 3 continue to work. When the defrosting of the two groups of medium heat exchange assemblies 3 is completed, the normal work is started, and the other two groups of medium heat exchange assemblies 3 in the same group can enter defrosting, and the other systems continue to work;

[0082] Low-temperature stage magnetic suspension two-stage compressor 1 enthalpy increasing and cooling mode:

[0083] The low-temperature low-pressure liquid refrigerant after the throttling of the enthalpy increasing electronic expansion valve 19 enters the plate-type economic heat exchanger 18 again to evaporate into medium-temperature medium-pressure gaseous refrigerant and then enters the enthalpy increasing port of the low-temperature stage magnetic suspension two-stage compressor 1; the medium-temperature medium-pressure liquid refrigerant enters the motor cooling and driving cooling port of the low-temperature stage magnetic suspension two-stage compressor 1 through the second three-way valve 21 at the same time

[0084] High-temperature stage magnetic suspension two-stage compressor 2 cooling mode:

[0085] The medium-temperature medium-pressure refrigerant enters the motor cooling and driving cooling port of the high-temperature stage magnetic suspension two-stage compressor 2 through the first three-way valve 21.

[0086] Example two:

[0087] As shown in Figures 4-7 ,

[0088] The double-head four-stage magnetic suspension air energy heat pump cold and hot water unit includes a low-temperature stage magnetic suspension two-stage compressor 1, a high-temperature stage magnetic suspension two-stage compressor 2, a plurality of medium heat exchange assemblies 3, a plate-type economic heat exchanger 18, an enthalpy increasing electronic expansion valve 19, a first three-way valve 20, and a second three-way valve 21.

[0089] Each group of medium heat exchange assembly 3 includes condenser 5, one-way valve pipe group 6, first main electronic expansion valve 7, second main electronic expansion valve 8, finned evaporator 9, first main electronic expansion valve 7, second main electronic expansion valve 8 are placed in parallel, one-way valve pipe group 6 includes first one-way valve 10, second one-way valve 11, third one-way valve 12, fourth one-way valve 13; The inlet end of first one-way valve 10, the outlet end of second one-way valve 11 are all communicated with the outlet end of its corresponding condenser 5, the inlet end of second one-way valve 11, the inlet end of third one-way valve 12 are all communicated with the outlet end of its corresponding first main electronic expansion valve 7, second main electronic expansion valve 8, the outlet end of third one-way valve 12, the inlet end of fourth one-way valve 13 are all communicated with the inlet end of its corresponding finned evaporator 9, the outlet end of first one-way valve 10, the outlet end of fourth one-way valve 13 are all communicated with the inlet end of its corresponding first main electronic expansion valve 7, second main electronic expansion valve 8;

[0090] The outlet end of low-temperature stage magnetic suspension double-stage compressor 1 is provided with four-way valve 14, the outlet end of several finned evaporators 9 is all communicated with the second outlet end of four-way valve 14 of low-temperature stage magnetic suspension double-stage compressor 1;

[0091] The first inlet end of four-way valve 14 is communicated with the outlet end of low-temperature stage magnetic suspension double-stage compressor 1, the first outlet end of four-way valve 14 is communicated with the inlet end of high-temperature stage magnetic suspension double-stage compressor 2, the first inlet end of several condensers 5 is all communicated with the first outlet end of four-way valve 14, the second inlet end of four-way valve 14 is communicated with the inlet end of low-temperature stage magnetic suspension double-stage compressor 1, the second inlet end of four-way valve 14 and low-temperature stage magnetic suspension double-stage compressor 1 are provided with gas-liquid separator 15, the first outlet end of four-way valve 14 is also simultaneously communicated with the inlet end of high-temperature stage magnetic suspension double-stage compressor 2, the outlet end of high-temperature stage magnetic suspension double-stage compressor 2 is provided with one-way valve 4, the outlet end of one-way valve 4 is also simultaneously communicated with the first inlet end of several condensers 5 respectively, the first outlet end of four-way valve 14 and the first inlet end of several condensers 5 are provided with two-way valve 16, the outlet end of two-way valve 16 is communicated with the first outlet end of four-way valve 14;

[0092] The second inlet and the second outlet of several condensers 5 are connected by two water route medium pipes 17 respectively.

[0093] The outlet end of each first one-way valve 10, the outlet end of the fourth one-way valve 13, the inlet end of the first main electronic expansion valve 7, and the inlet end of the second main electronic expansion valve 8 are connected to the first port of the first three-way valve 20, the third port of the first three-way valve 20 is connected to the first port of the second three-way valve, the second port of the second three-way valve 20 is connected to the first inlet end of the plate-type economic heat exchanger 18, the motor cooling and driving cooling port of the high-temperature stage magnetic suspension two-stage compressor 2 is connected to the second end of the first three-way valve 20, the first outlet end of the plate-type economic heat exchanger 18 is connected to the inlet end of the enthalpy-increasing electronic expansion valve 19, and the outlet end of the enthalpy-increasing electronic expansion valve 19 is connected to the enthalpy-increasing port of the low-temperature stage magnetic suspension two-stage compressor 1.

[0094] A second three-way valve 21 is additionally arranged near the third port of the first three-way valve 20 connected to the first inlet end of the plate-type economic heat exchanger 18, and the third port of the second three-way valve 21 is connected to the motor cooling and driving cooling port of the low-temperature stage magnetic suspension two-stage compressor 1.

[0095] The medium heat exchange assembly 3 is also provided with an auxiliary road electronic expansion valve 22 in parallel.

[0096] The working method of the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit includes a heating mode, a cooling mode, a defrosting mode, and a temperature reduction mode.

[0097] Heating mode:

[0098] Step one: the low-temperature stage magnetic suspension two-stage compressor 1 and the high-temperature stage magnetic suspension two-stage compressor 2 work, and the refrigerant heat exchange medium in the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system flows;

[0099] Step two: the medium-temperature and medium-pressure refrigerant enters the first one-way valve 10 from the condenser 5, the medium-temperature and medium-pressure refrigerant enters the first main electronic expansion valve 7 and the second main electronic expansion valve 8 through the first one-way valve 10, the first main electronic expansion valve 7 and the second main electronic expansion valve 8 throttle, depressurize, and cool the refrigerant, and then form low-temperature and low-pressure gaseous refrigerant into the third one-way valve 12;

[0100] The low-temperature and low-pressure gaseous refrigerant entering the third one-way valve 12 enters the finned evaporator 9, and the low-temperature and low-pressure gaseous refrigerant entering the finned evaporator 9 exchanges heat with air to evaporate to form medium-temperature and medium-pressure gaseous refrigerant;

[0101] Step three: the medium temperature and pressure gaseous refrigerant in the finned evaporator 9 of several medium heat exchange assemblies 3 enters the second outlet end of the four-way valve 14, then enters the second inlet end of the four-way valve 14 to the inlet end of the gas-liquid separator 15, and finally enters the low-temperature stage magnetic suspension double-stage compressor 1 from the outlet end of the gas-liquid separator 15 for compression. The low-temperature and low-pressure gaseous refrigerant enters the low-temperature stage magnetic suspension double-stage compressor 1 for compression to form high-temperature and high-pressure gaseous refrigerant. Then the high-temperature and high-pressure gaseous refrigerant enters the high-temperature stage magnetic suspension double-stage compressor 2 through the first outlet end of the four-way valve 14 to form super-high-temperature and high-pressure gaseous refrigerant.

[0102] Step four: the super-high-temperature and high-pressure gaseous refrigerant enters the several condensers 5 and exchanges heat with the water medium in the condenser 5 through the first one-way valve 4 to form medium-temperature and pressure refrigerant.

[0103] Step five: repeat steps two, three, and four.

[0104] Refrigeration mode:

[0105] Step one: the low-temperature stage magnetic suspension double-stage compressor 1 works, and the refrigerant medium in the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system flows.

[0106] Step two: the high-temperature and high-pressure gaseous refrigerant enters the several finned evaporators 9 through the second inlet end of the four-way valve 14 to exchange heat with air and reduce pressure and temperature to form medium-temperature and pressure liquid refrigerant. Then the refrigerant enters the fourth one-way valve 13, and then enters the first main electronic expansion valve 7 and the second main electronic expansion valve 8 through the fourth one-way valve 13. The first main electronic expansion valve 7 and the second main electronic expansion valve 8 throttle, depressurize, and cool the refrigerant to become low-temperature and low-pressure gaseous refrigerant. Then the low-temperature and low-pressure gaseous refrigerant enters the second one-way valve 11.

[0107] Step three: the low-temperature and low-pressure gaseous refrigerant enters the condenser 5 and exchanges heat with the water medium in the condenser 5 through the second one-way valve 11, and then evaporates into medium-temperature and pressure gaseous refrigerant. The medium-temperature and pressure gaseous refrigerant enters the second one-way valve 16 from the condenser 5, enters the first outlet end of the four-way valve 14, then enters the second inlet end of the gas-liquid separator 15, and finally enters the low-temperature stage magnetic suspension double-stage compressor 1 from the outlet end of the gas-liquid separator 15 for compression. The medium-temperature and pressure gaseous refrigerant enters the low-temperature stage magnetic suspension double-stage compressor 1 for compression to form high-temperature and high-pressure gaseous refrigerant.

[0108] Step four: repeat steps two to three.

[0109] Defrosting mode:

[0110] When the following conditions are met simultaneously: ambient temperature ≤ set entering defrosting ring temperature; double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system cumulative running time ≥ set entering defrosting interval time, ambient temperature - return air temperature ≥ set ambient temperature - return air temperature, and the duration ≥ 3 minutes, at this time, the low-temperature stage magnetic suspension two-stage compressor 1 and the medium heat exchange assembly 3 enter defrosting;

[0111] Only two groups of medium heat exchange assemblies 3 in the same group of several medium heat exchange assemblies 3 are allowed to defrost at the same time, and the other medium heat exchange assemblies 3 continue to work. When the defrosting of the two groups of medium heat exchange assemblies 3 is completed, the normal work is started, and the other two groups of medium heat exchange assemblies 3 in the same group can enter defrosting, and the other systems continue to work.

[0112] Low-temperature stage magnetic suspension two-stage compressor 1 enthalpy increasing and cooling mode:

[0113] The low-temperature stage magnetic suspension two-stage compressor 1 enthalpy increasing and cooling mode:

[0114] High-temperature stage magnetic suspension two-stage compressor 2 cooling mode:

[0115] The high-temperature stage magnetic suspension two-stage compressor 2 cooling mode:

[0116] Example three:

[0117] As shown in Figures 8-10 ,

[0118] The double-head four-stage magnetic suspension air energy heat pump cold and hot water unit includes a low-temperature stage magnetic suspension two-stage compressor 1, a high-temperature stage magnetic suspension two-stage compressor 2, a shell and tube heat exchanger 23, a first main electronic expansion valve 7, a plurality of finned evaporators 9, and a four-way valve 14.

[0119] The plurality of finned evaporators 9 are connected in parallel.

[0120] The first inlet end of the four-way valve 14 is connected to the outlet end of the low-temperature stage magnetic suspension two-stage compressor 1, the outlet end of the plurality of finned evaporators 9 is connected to the second outlet end of the four-way valve 14, the second inlet end of the four-way valve 14 is provided with a gas-liquid separator 15, the outlet end of the gas-liquid separator 15 is connected to the inlet end of the low-temperature stage magnetic suspension two-stage compressor 1, and the first outlet end of the four-way valve 14 is connected to the inlet end of the high-temperature stage magnetic suspension two-stage compressor 2.

[0121] The outlet end of the high-temperature magnetic suspension two-stage compressor 2 is provided with a one-way valve 4, the outlet end of the one-way valve 4 is connected with the inlet end of the shell-and-tube heat exchanger 23, the outlet end of the shell-and-tube heat exchanger 23 is provided with a first three-way valve 20 and a first main electronic expansion valve 7, the second port of the first three-way valve 20 is connected with the first main electronic expansion valve 7, and the first main electronic expansion valve 7 is connected with the inlet end of the plurality of finned evaporators 9;

[0122] The inlet end of the shell-and-tube heat exchanger 23 is also provided with a second one-way valve 16, and the outlet end of the second one-way valve 16 is connected with the first outlet end of the four-way valve 14.

[0123] The system further comprises a plate-type economic heat exchanger 18, an enthalpy-increasing electronic expansion valve 19, a second three-way valve 21 and a third three-way valve 24.

[0124] The third port of the third three-way valve 24 is connected with the motor cooling and driving cooling port of the low-temperature magnetic suspension two-stage compressor 1.

[0125] The third port of the second three-way valve 21 is connected with the first inlet of the plate-type economic heat exchanger 18, the first outlet end of the plate-type economic heat exchanger 18 is connected with the inlet end of the enthalpy-increasing electronic expansion valve 19, the outlet end of the enthalpy-increasing electronic expansion valve 19 is connected with the second inlet of the plate-type economic heat exchanger 18, and the second outlet of the plate-type economic heat exchanger 18 is connected with the enthalpy-increasing port of the low-temperature magnetic suspension two-stage compressor 1.

[0126] The second port of the third three-way valve 24 is connected with the motor cooling and driving cooling port of the high-temperature magnetic suspension two-stage compressor 2.

[0127] The inlet end of the shell-and-tube heat exchanger 23 is connected with the outlet end of the plurality of finned evaporators 9 through an auxiliary electronic expansion valve 22.

[0128] A working method of the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit,

[0129] The working method comprises a heating mode, a cooling mode, a defrosting mode and a temperature-reducing mode.

[0130] The heating mode:

[0131] Step one: the low-temperature magnetic suspension two-stage compressor 1 and the high-temperature magnetic suspension two-stage compressor 2 work, and the refrigerant medium in the system of the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit flows;

[0132] Step two: the medium-temperature and medium-pressure liquid refrigerant enters the first main electronic expansion valve 7 from the outlet end of the shell-and-tube heat exchanger 23 to throttle, depressurize and cool the refrigerant, then the low-temperature and low-pressure gaseous refrigerant formed by throttling, depressurizing and cooling enters the finned evaporator 9, and the low-temperature and low-pressure gaseous refrigerant exchanges heat with air in the finned evaporator 9 to form the medium-temperature and medium-pressure gaseous refrigerant.

[0133] Step three: the medium temperature and medium pressure gaseous refrigerant formed by the several finned evaporators 9 enters from the second outlet end of the four-way valve 14, then from the second inlet end of the four-way valve 14 to the inlet end of the gas-liquid separator 15, and finally from the outlet end of the gas-liquid separator 15 into the low-temperature stage magnetic suspension two-stage compressor 1 for compression, the low-temperature and low-pressure gaseous refrigerant enters the low-temperature stage magnetic suspension two-stage compressor 1 for compression to form high-temperature and high-pressure gaseous refrigerant, and then the high-temperature and high-pressure gaseous refrigerant passes through the first inlet end and then the first outlet end of the four-way valve 14, and then enters from the first outlet end of the four-way valve 14 into the high-temperature stage magnetic suspension two-stage compressor 2 for compression to form super-high-temperature and high-pressure gaseous refrigerant;

[0134] Step four: the super-high-temperature and high-pressure gaseous refrigerant enters the one-way valve 4, and then enters the shell-and-tube heat exchanger 23 through the one-way valve 4 for heat exchange to form medium-temperature and medium-pressure liquid refrigerant;

[0135] Step five: repeat steps two, three, and four;

[0136] Step six: in the lower ambient temperature case in the heating mode, the enthalpy increase is started to improve the heating capacity by 10-20;

[0137] Refrigeration and defrosting mode:

[0138] Step one: the low-temperature stage magnetic suspension two-stage compressor 1 works, and the refrigerant medium in the dual-head four-stage magnetic suspension air energy heat pump cold and hot water unit system flows;

[0139] Step two: the high-temperature and high-pressure gaseous refrigerant in the low-temperature stage magnetic suspension two-stage compressor 1 enters the first inlet end of the four-way valve 14, and then enters the several finned evaporators 9 through the second outlet end of the four-way valve 14 for heat exchange with air to reduce pressure and temperature, forming medium-temperature and medium-pressure liquid refrigerant;

[0140] Then, the medium-temperature and medium-pressure liquid refrigerant enters the first main electronic expansion valve 7, which throttles, depressurizes, and cools the refrigerant to become low-temperature and low-pressure gaseous refrigerant;

[0141] Then the low-temperature and low-pressure gaseous refrigerant enters the shell-and-tube heat exchanger 23 for heat exchange with water medium and temperature reduction and evaporation, forming medium-temperature and medium-pressure gaseous refrigerant.

[0142] The medium-temperature and medium-pressure liquid refrigerant also simultaneously exits from the third port of the first three-way valve 20, passes through the second three-way valve 21, enters the third three-way valve 24, and enters the cooling mode;

[0143] The medium-temperature and medium-pressure liquid refrigerant enters the motor cooling and driving cooling port of the low-temperature stage magnetic suspension two-stage compressor 1 through the third port of the third three-way valve 24;

[0144] When the higher ambient temperature is refrigerated, the enthalpy-increasing electronic expansion valve 19 is opened, the liquid refrigerant at medium temperature and medium pressure enters the plate-type economic heat exchanger 18 through the third port of the second three-way valve 21, enters the enthalpy-increasing electronic expansion valve 19 for throttling, and the gaseous refrigerant at low temperature and low pressure after throttling of the enthalpy-increasing electronic expansion valve 19 enters the plate-type economic heat exchanger 18 again, evaporates into gaseous refrigerant at medium temperature and medium pressure, and then enters the enthalpy-increasing port of the low-temperature-stage magnetic suspension two-stage compressor 1;

[0145] Step three: the gaseous refrigerant at medium temperature and medium pressure enters the second one-way valve 16 from the outlet end of the shell-and-tube heat exchanger 23, then enters the first outlet end of the four-way valve 14 from the outlet end of the second one-way valve 16, enters the four-way valve 14 from the first outlet end, then enters the gas-liquid separator 15 from the second inlet end, and finally enters the low-temperature-stage magnetic suspension two-stage compressor 1 from the outlet end of the gas-liquid separator 15 for compression, the gaseous refrigerant at medium temperature and medium pressure enters the low-temperature-stage magnetic suspension two-stage compressor 1 for compression to form gaseous refrigerant at high temperature and high pressure;

[0146] Step four: repeat steps two to three;

[0147] Defrosting mode:

[0148] When the following conditions are met simultaneously: ambient temperature ≤ set entering defrosting ambient temperature; cumulative running time of the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system ≥ set entering defrosting interval time, ambient temperature - return air temperature ≥ set ambient temperature - return air temperature difference, and the duration ≥ 3 minutes, the low-temperature-stage double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system enters defrosting.

[0149] The specific embodiment is only an explanation of the present application, and is not a limitation of the present application, and those skilled in the art can make modifications to the embodiment without creative contribution according to the needs after reading the specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. Double-head four-stage magnetic levitation air energy heat pump hot and cold water unit, characterized in that: The application relates to a magnetic suspension double-stage compressor system. The outlet end of the low-temperature stage magnetic suspension double-stage compressor (1) is connected with the inlet end of the high-temperature stage magnetic suspension double-stage compressor (2), and a first one-way valve (4) is arranged at the connecting position; the inlet end of the first one-way valve (4) is connected with the outlet end of the low-temperature stage magnetic suspension double-stage compressor (1); and the outlet end of the first one-way valve (4) is connected with the inlet end of the high-temperature stage magnetic suspension double-stage compressor (2). Each group of medium heat exchange assemblies (3) comprises a condenser (5), a one-way valve pipe group (6), a first main electronic expansion valve (7), a second main electronic expansion valve (8) and a finned evaporator (9); the first main electronic expansion valve (7) and the second main electronic expansion valve (8) are arranged in parallel; the one-way valve pipe group (6) comprises a first one-way valve (10), a second one-way valve (11), a third one-way valve (12) and a fourth one-way valve (13); the inlet end of the first one-way valve (10) and the outlet end of the second one-way valve (11) are connected with the first outlet end of the corresponding condenser (5); the inlet end of the second one-way valve (11) and the inlet end of the third one-way valve (12) are connected with the outlet end of the corresponding first main electronic expansion valve (7) and second main electronic expansion valve (8); the outlet end of the third one-way valve (12) and the inlet end of the fourth one-way valve (13) are connected with the inlet end of the corresponding finned evaporator (9); and the outlet end of the first one-way valve (10) and the outlet end of the fourth one-way valve (13) are connected with the inlet end of the corresponding first main electronic expansion valve (7) and second main electronic expansion valve (8). The outlet end of each finned evaporator (9) is provided with a four-way valve (14); the outlet end of each finned evaporator (9) is connected with the second outlet end of the corresponding four-way valve (14); the first inlet end of each condenser (5) is connected with the first outlet end of the corresponding four-way valve (14); the second inlet ends of the four-way valves (14) are connected with each other and are provided with a gas-liquid separator (15) at the connecting position; the outlet end of the gas-liquid separator (15) is connected with the inlet end of the high-temperature stage magnetic suspension double-stage compressor (2) and the inlet end of the low-temperature stage magnetic suspension double-stage compressor (1); a second one-way valve (16) is arranged between the outlet end of the gas-liquid separator (15) and the inlet end of the high-temperature stage magnetic suspension double-stage compressor (2); the outlet end of the first one-way valve (4) is connected with the outlet end of the second one-way valve (16) and the inlet end of the high-temperature stage magnetic suspension double-stage compressor (2); and the outlet end of the high-temperature stage magnetic suspension double-stage compressor (2) is connected with the first inlet end of each four-way valve (14). The second inlet and the second outlet of each condenser (5) are provided with two water route medium pipelines (17).

2. The double-head four-stage magnetic levitation air energy heat pump hot and cold water chiller set according to claim 1, characterized in that: The application further comprises a plate-type economic heat exchanger (18), an enthalpy-increasing electronic expansion valve (19), a first three-way valve (20) and a second three-way valve (21). The outlet end of each first one-way valve (10), the outlet end of the fourth one-way valve (13), the inlet end of the first main electronic expansion valve (7), and the inlet end of the second main electronic expansion valve (8) are connected to the first port of the first three-way valve (20), the second port of the first three-way valve (20) is connected to the motor cooling and driving cooling port of the high-temperature stage magnetic suspension two-stage compressor (2), the third port of the first three-way valve (20) is connected to the first port of the second three-way valve (21), the second port of the second three-way valve (21) is connected to the first inlet end of the plate-type economic heat exchanger (18), the first outlet end of the plate-type economic heat exchanger (18) is connected to the inlet end of the enthalpy-increasing electronic expansion valve (19), the outlet end of the enthalpy-increasing electronic expansion valve (19) is connected to the second inlet end of the plate-type economic heat exchanger (18), and the second outlet end of the plate-type economic heat exchanger (18) is connected to the enthalpy-increasing port of the low-temperature stage magnetic suspension two-stage compressor (1); The third port of the first three-way valve (20) is additionally provided with the second three-way valve (21) connected to the first inlet end of the plate-type economic heat exchanger (18) and the motor cooling and driving cooling port of the low-temperature stage magnetic suspension two-stage compressor (1).

3. The double-head four-stage magnetic levitation air energy heat pump hot and cold water chiller set according to claim 2, characterized in that: The inlet end of the gas-liquid separator (15) is provided with the auxiliary road electronic expansion valve (22) connected between the outlet end of the high-temperature stage magnetic suspension two-stage compressor (2), the inlet of the auxiliary road electronic expansion valve (22) is connected to the first inlet end of the plurality of four-way valves (14), and the outlet of the auxiliary road electronic expansion valve (22) is connected to the inlet end of the gas-liquid separator (15).

4. A working method of a double-head four-stage magnetic suspension air energy heat pump cold and hot water unit, used in the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit of claim 3, characterized in that: It comprises a heating mode, a cooling mode, a defrosting mode, and a temperature reduction mode. In the heating mode: Step one: the low-temperature stage magnetic suspension two-stage compressor (1) and the high-temperature stage magnetic suspension two-stage compressor (2) work, and the refrigerant heat medium in the double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system flows; Step two: the medium-temperature and medium-pressure liquid refrigerant enters the first one-way valve (10) from the condenser (5), the medium-temperature and medium-pressure refrigerant enters the first main electronic expansion valve (7) and the second main electronic expansion valve (8) through the first one-way valve (10), the first main electronic expansion valve (7) and the second main electronic expansion valve (8) throttle, depressurize, and cool the refrigerant, and then the low-temperature and low-pressure gaseous refrigerant formed enters the third one-way valve (12); The low-temperature and low-pressure gaseous refrigerant entering the third one-way valve (12) enters the finned evaporator (9), and the low-temperature and low-pressure gaseous refrigerant entering the finned evaporator (9) exchanges heat with air to evaporate and form medium-temperature and medium-pressure gaseous refrigerant; Step 3: The medium-temperature and medium-pressure gaseous refrigerant formed by the finned evaporator (9) of several medium heat exchange components (3) enters from the second outlet end of its corresponding four-way valve (14), then from the second inlet end of several four-way valves (14) to the inlet end of the gas-liquid separator (15), and finally from the outlet end of the gas-liquid separator (15) into the low-temperature magnetic levitation two-stage compressor (1) for compression. The low-temperature and low-pressure gaseous refrigerant enters the low-temperature magnetic levitation two-stage compressor (1) to form a high-temperature and high-pressure gaseous refrigerant. Then, the high-temperature and high-pressure gaseous refrigerant passes through the first check valve (4) and enters the high-temperature magnetic levitation two-stage compressor (2) to form an ultra-high-temperature and high-pressure gaseous refrigerant. At this time, the high-temperature and high-pressure gaseous refrigerant blocks the second check valve (16). Step 4: The ultra-high temperature and high pressure gaseous refrigerant enters the first inlet end of several four-way valves (14), and then enters the corresponding condenser (5) through the first outlet end of several four-way valves (14), where it exchanges heat with the water medium in the condenser (5) to form a medium temperature and medium pressure refrigerant. The water medium after heat exchange in the condenser (5) enters the indoor unit for heat exchange through the water medium pipeline (17). Step 5: Repeat steps 2, 3, and 4; Cooling and defrosting modes: Step 1: The high-temperature magnetic levitation two-stage compressor (2) is working, and the heat exchange medium flows in the dual-head four-stage magnetic levitation air source heat pump chiller system. Step 2: The high-temperature and high-pressure gaseous refrigerant in the high-temperature magnetic levitation two-stage compressor (2) enters the first inlet end of several four-way valves (14), and enters several finned evaporators (9) through the second outlet end of several four-way valves (14) to exchange heat with air, reduce pressure and temperature, and form a medium-temperature and medium-pressure liquid refrigerant. Medium-temperature and medium-pressure liquid refrigerant enters the fourth check valve (13), and through the fourth check valve (13) it enters the first main electronic expansion valve (7) and the second main electronic expansion valve (8). The first main electronic expansion valve (7) and the second main electronic expansion valve (8) throttle, reduce pressure and cool the refrigerant, turning it into a low-temperature and low-pressure gaseous refrigerant. Subsequently, the low-temperature and low-pressure gaseous refrigerant enters the second check valve (11). Step 3: The low-temperature and low-pressure gaseous refrigerant enters its corresponding condenser (5) through the second one-way valve (11) and exchanges heat with the water medium in the condenser (5). After evaporation, it becomes a medium-temperature and medium-pressure gaseous refrigerant. The medium-temperature and medium-pressure gaseous refrigerant enters the first outlet end of its corresponding four-way valve (14) from the condenser (5). The medium-temperature and medium-pressure gaseous refrigerant enters from the first outlet end of the four-way valve (14), then from the second inlet end to the inlet end of the gas-liquid separator (15), and finally from the outlet end of the gas-liquid separator (15) into the second one-way valve (16). At the same time, the first one-way valve is blocked to prevent the medium-temperature and medium-pressure gaseous refrigerant from entering the low-temperature stage magnetic levitation two-stage compressor (1). It enters the high-temperature stage magnetic levitation two-stage compressor (2) from the second one-way valve (16) and is compressed. The medium-temperature and medium-pressure gaseous refrigerant enters the high-temperature stage magnetic levitation two-stage compressor (2) and is compressed to form a high-temperature and high-pressure gaseous refrigerant. Step 4: Repeat steps 2 and 3; Defrosting mode: When the following conditions are met simultaneously: ambient temperature ≤ set entering defrosting ring temperature; double-head four-stage magnetic suspension air energy heat pump cold and hot water unit system cumulative running time ≥ set entering defrosting interval time, ambient temperature - return air temperature ≥ set ambient temperature - return air temperature, and the duration ≥ 3 minutes, at this time, the low-temperature stage magnetic suspension two-stage compressor (1) and the medium heat exchange assembly (3) enter defrosting; Only two groups of medium heat exchange assemblies (3) in the same group of several medium heat exchange assemblies (3) are allowed to defrost at the same time, and the other medium heat exchange assemblies (3) continue to work. When the defrosting of the two groups of medium heat exchange assemblies (3) is completed, start to enter normal work, and the other two groups of medium heat exchange assemblies (3) in the same group can enter defrosting, and other systems continue to work; Low-temperature stage magnetic suspension two-stage compressor (1) enthalpy increasing and cooling mode: The medium-temperature medium-pressure liquid refrigerant enters the plate-type economic heat exchanger (18) from the second three-way (21) through the first three-way (20), and then enters the enthalpy increasing electronic expansion valve (19) after throttling. The low-temperature low-pressure liquid refrigerant after throttling enters the plate-type economic heat exchanger (18) again to evaporate into medium-temperature medium-pressure gaseous refrigerant, and then enters the enthalpy increasing port of the low-temperature stage magnetic suspension two-stage compressor (1). The medium-temperature medium-pressure liquid refrigerant enters the motor cooling and driving cooling port of the low-temperature stage magnetic suspension two-stage compressor (1) through the third port of the second three-way (21) at the same time High-temperature stage magnetic suspension two-stage compressor (2) cooling mode: The medium-temperature medium-pressure refrigerant enters the motor cooling and driving cooling port of the high-temperature stage magnetic suspension two-stage compressor (2) from the first three-way (20).

Images