Solar heat pump heat supply system based on quasi-two-stage compression and heat supply method thereof

Abstract

According to the solar heat pump heat supply system based on quasi-two-stage compression and the heat supply method of the solar heat pump heat supply system, the concept is novel, the design is optimized and ingenious, the condensation heat exchange amount can be effectively increased through an air supply enthalpy increasing compressor, the exhaust temperature of the compressor can be effectively reduced through the air supply technology, and efficient and stable operation of the system under the ultralow-temperature large-temperature-area variable working condition is achieved; meanwhile, the air supply enthalpy increasing compressor and the heat storage water tank are arranged, the condensation heat exchange amount can be effectively increased, and therefore circulating air with the higher temperature can be obtained; solar energy is adopted as an auxiliary heat source, the evaporation temperature of the heat pump system can be increased, then the efficiency of the whole solar heat pump heat supply system is improved, efficient heating is achieved, and meanwhile uninterrupted supply of domestic hot water can be achieved; a solar heat collection technology and a quasi-two-stage compression heat pump technology are coupled, advantage complementation of the two systems is achieved, the energy efficiency ratio of the whole solar heat pump heat supply system is improved, the service life of equipment is prolonged, and the annual operation efficiency, reliability and economical efficiency of a solar heat pump unit are improved.

Description

Technical Field

[0001] The invention relates to the technical field of solar heat pump heating, and in particular to a solar heat pump heating system based on quasi-two-stage compression and a heating method thereof. Background Art

[0002] Affected by seasonal factors, the biggest drawback of solar energy utilization is that it is not continuous and stable. When only solar energy is used as a single heat source, it is impossible to provide heat to users continuously and stably. The heat pump is a stable and effective heating equipment. By utilizing the energy in the low-temperature heat source and consuming a small amount of electricity, a large amount of heat can be obtained. It can effectively utilize low-grade energy that is not enough for direct application, thereby achieving the goal of energy saving. Therefore, combining solar energy technology and heat pump technology can make the heating system more efficient and stable.

[0003] However, in the existing solar heat pump coupling system, the compressor exhaust temperature is too high under ultra-low temperature ambient temperature, resulting in a significant reduction in the system heat exchange and COP (heating performance coefficient, i.e. heating capacity per unit power), and the system cannot continue to operate efficiently. Summary of the invention

[0004] The purpose of the present invention is to provide a solar heat pump heating system based on quasi-two-stage compression and a heating method thereof, which adopts solar energy as an auxiliary heat source, can increase the evaporation temperature of the heat pump system, and thus improve the efficiency of the heat pump system; at the same time, the quasi-two-stage compression heat pump system adopts an air-injection enthalpy-increasing compressor, which can effectively reduce the compressor exhaust temperature by air injection, so as to solve the problems faced by the existing solar heat pump coupling system under ultra-low temperature and large temperature difference conditions, such as excessively high exhaust temperature, serious heating capacity attenuation, and the system cannot operate efficiently and stably.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a solar heat pump heating system based on quasi-two-stage compression, including a quasi-two-stage compression heat pump system and a solar heat collection system, wherein the quasi-two-stage compression heat pump system includes a compressor, a condenser, a liquid storage device, a drying filter, a plate heat exchanger 1, an evaporator, an evaporation fan, a plate heat exchanger 2, a gas-liquid separator, an expansion water tank, a fan coil, a water pump 1, a water pump 2, a hot water storage tank, an intermediate heat exchanger 1 and an intermediate heat exchanger 2, and the solar heat collection system includes a solar heat collector, a water pump 3, a water pump 4, a water pump 5 and a hot water supply device, wherein:

[0007] The inlet of the compressor is connected to the interface pipes of the evaporator and the plate heat exchanger 2 through the gas-liquid separator, the outlet of the compressor is connected to the interface pipe of the condenser through a multi-way valve, the outlet of the drying filter is connected to the inlet of the plate heat exchanger 1, and the outlet of the plate heat exchanger 1 is divided into two routes: one route is connected to the inlet of the evaporator and the plate heat exchanger 2 through the throttle valve 1, and the other route is connected to the air supply port of the compressor through the throttle valve 2, the plate heat exchanger 1, and the valve 1; the compressor is an air supply enthalpy increase compressor;

[0008] The expansion water tank is connected to the condenser through a pipeline and the first water pump, the inlet and outlet of the fan coil are connected to the expansion water tank through a pipeline, and the second water pump is arranged on the connecting pipeline between the fan coil and the expansion water tank, and the fan coil is arranged in the room; the evaporator is connected to the evaporation fan, and the evaporator and the evaporation fan are connected to the air duct of the room through an air duct;

[0009] The intermediate heat exchanger 1 and the intermediate heat exchanger 2 are arranged inside the heat storage tank, the inlet and outlet of the solar collector are connected to the outlet and inlet of the intermediate heat exchanger 1 through pipes, and the water pump 3 is arranged on the connecting pipe between the solar collector and the intermediate heat exchanger 1; the outlet and inlet of the intermediate heat exchanger 2 are connected to the inlet and outlet of the plate heat exchanger 2 through pipes, and the water pump 5 is arranged on the connecting pipe between the intermediate heat exchanger 2 and the plate heat exchanger 2; the outlet and inlet of the heat storage tank are connected to the inlet and outlet of the hot water supply device through pipes, and the valve 2 and the water pump 4 are arranged on the connecting pipe between the heat storage tank and the hot water supply device.

[0010] Preferably, the air-injection and heat-increasing compressor is a fixed-frequency compressor with an air-injection and heat-increasing function, a variable-speed compressor with an air-injection and heat-increasing function, or a digital scroll compressor with an air-injection and heat-increasing function.

[0011] Preferably, the multi-way valve is a four-way valve, the gas-liquid separator is connected to the evaporator via the four-way valve, and the gas-liquid separator is connected to the second plate heat exchanger via the four-way valve.

[0012] Preferably, the refrigerant inlet of the evaporator and the refrigerant inlet of the second plate heat exchanger are respectively provided with a first solenoid valve and a second solenoid valve.

[0013] Preferably, the condenser is a shell and tube heat exchanger or a plate heat exchanger; the evaporator is a parallel flow heat exchanger or a fin-tube heat exchanger; the intermediate heat exchanger 1 and the intermediate heat exchanger 2 are coil heat exchangers; and the solar collector is a trough solar collector or a flat plate solar collector.

[0014] Preferably, the evaporation fan is a variable frequency fan, a fixed frequency fan or a speed-adjustable fan.

[0015] Preferably, the throttle valve 1 and the throttle valve 2 are any one of a thermal expansion valve, an electronic expansion valve, a manual expansion valve, a choke expansion valve and a float expansion valve.

[0016] Preferably, the water pump one, the water pump two, the water pump three, the water pump four and the water pump five are all volumetric water pumps or vane pumps.

[0017] The present invention further proposes a heating method of the solar heat pump heating system based on quasi-two-stage compression as described in any one of the above, comprising:

[0018] Refrigerant side circulation mode: the high-temperature and high-pressure gas from the compressor enters the condenser through the multi-way valve, and after being cooled into a low-temperature and high-pressure liquid by the condenser, it passes through the liquid storage device and the drying filter in sequence and enters the plate heat exchanger 1, and then is divided into two paths: one path passes through the throttle valve 1 to become a low-temperature and low-pressure liquid, and then enters the evaporator and the plate heat exchanger 2 to evaporate and absorb heat to become a superheated gas, and then enters the compressor through the gas-liquid separator for compression; the other path passes through the throttle valve 2 and enters the plate heat exchanger 1 again, and then enters the compressor through the air supply opening of the compressor;

[0019] Fan coil water side circulation mode: the circulating water in the expansion water tank passes through the water pump 1 to perform heat exchange with the high-temperature and high-pressure refrigerant in the condenser, and the circulating water heated by heat exchange enters the expansion water tank; at the same time, the circulating water heated by heat exchange passes through the water pump 2 to enter the fan coil and perform heat exchange with the return air in the room;

[0020] Solar collector water side circulation mode: After the circulating water is heated by the solar collector, it enters the intermediate heat exchanger 1 to exchange heat with the circulating water in the hot water storage tank, and then returns to the solar collector through the water pump 3; after the circulating water in the intermediate heat exchanger 2 exchanges heat with the circulating water in the hot water storage tank, it exchanges heat with the refrigerant in the plate heat exchanger 2 through the water pump 5; at the same time, the circulating water in the hot water storage tank flows into the hot water supply device through the water pump 4 and the valve 2 to provide domestic water;

[0021] Evaporator air side circulation mode: the room return air is cooled and dehumidified after passing through the evaporator, and the circulating air after dehumidification is sent back to the room by the evaporator fan;

[0022] Fan coil air side circulation mode: the room return air is heated after passing through the fan coil, and the heated circulating air is sent into the room for heating.

[0023] Compared with the prior art, the present invention has achieved the following technical effects:

[0024] The solar heat pump heating system and heating method based on quasi-two-stage compression proposed in the present invention have novel concept and ingenious unit design optimization. Compared with the prior art, they have the following advantages and outstanding effects:

[0025] (1) In the existing solar heat pump system, the compressor exhaust temperature is too high under ultra-low temperature environment, resulting in a significant attenuation of the system heat exchange and COP of the solar heat pump system, and the system cannot continue to operate efficiently. The system of the present invention adopts an air-injection enthalpy-increasing compressor to effectively increase the condensation heat exchange. The air-injection technology can effectively reduce the compressor exhaust temperature, and realize efficient and stable operation of the system under ultra-low temperature and large temperature range variable working conditions.

[0026] (2) The simultaneous installation of an air-supplying and heat-increasing compressor and a heat storage tank can effectively increase the condensation heat exchange capacity, thereby obtaining circulating air with a higher temperature;

[0027] (3) Using solar energy as an auxiliary heat source can increase the evaporation temperature of the heat pump system, thereby improving the efficiency of the entire solar heat pump heating system. While providing efficient heating, it can also achieve an uninterrupted supply of domestic hot water;

[0028] (4) The system adopts multiple heat exchangers, which can effectively reduce the humidity of the circulating air;

[0029] (5) The coupling of solar thermal collection technology and quasi-two-stage compression heat pump technology realizes the complementary advantages of the two systems. It not only solves the key technical problem of the inability to continuously, stably and efficiently provide heat when using solar energy as a single heat source, but also solves the existing solar heat pump system's problems of excessively high compressor exhaust temperature, greatly reduced heating capacity and COP, and the inability of the system to operate efficiently and stably for a long time under ultra-low temperature and large temperature difference environments. It improves the energy efficiency ratio of the entire solar heat pump heating system, extends the service life of the equipment, and improves the efficiency, reliability and economy of the solar heat pump unit's operation throughout the year. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 This is a system schematic diagram of a solar heat pump heating system based on quasi-two-stage compression disclosed in an embodiment of the present invention.

[0032] Figure 2 This is a working diagram of a solar heat pump heating system based on quasi-two-stage compression disclosed in an embodiment of the present invention (arrows in the diagram indicate the flow direction of corresponding media in the system).

[0033] In the figure: 100, a solar heat pump heating system based on quasi-two-stage compression; 1, compressor; 2, multi-way valve; 3, condenser; 4, non-return valve; 5, liquid storage tank; 6, drying filter; 7, plate heat exchanger one; 8, throttle valve one; 9, evaporator; 10, evaporating fan; 11, plate heat exchanger two; 12, gas-liquid separator; 13, throttle valve two; 14, valve one; 15, solenoid valve one; 16, solenoid valve two; 17, expansion water tank; 18, fan coil; 19, water pump one; 20, water pump two; 21, room; 22, hot water storage tank; 23, intermediate heat exchanger one; 24, intermediate heat exchanger two; 25, solar collector; 26, water pump three; 27, water pump four; 28, valve two; 29, water pump five; 30, hot water supply device. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] One of the purposes of the present invention is to provide a solar heat pump heating system based on quasi-two-stage compression, which uses solar energy as an auxiliary heat source, which can increase the evaporation temperature of the heat pump system, thereby improving the efficiency of the heat pump system; at the same time, the quasi-two-stage compression heat pump system uses an air-injection enthalpy-increasing compressor, which can effectively reduce the compressor exhaust temperature by air injection, so as to solve the problems faced by the existing solar heat pump coupling system under ultra-low temperature and large temperature difference conditions, such as excessively high exhaust temperature, serious heating capacity attenuation, and the system cannot operate efficiently and stably.

[0036] Another object of the present invention is to provide a heating method for the above-mentioned solar heat pump heating system based on quasi-two-stage compression.

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] This embodiment proposes a solar heat pump heating system 100 based on quasi-two-stage compression, including a quasi-two-stage compression heat pump system, a solar heat collection system and connecting pipes between various components. The quasi-two-stage compression heat pump system includes a compressor 1, a condenser 3, a one-way valve 4, a liquid storage tank 5, a drying filter 6, a plate heat exchanger 1 7, an evaporator 9, an evaporating fan 10, a plate heat exchanger 2 11, a gas-liquid separator 12, an expansion water tank 17, a fan coil 18, a water pump 1 19, a water pump 2 20, a hot water storage tank 22, an intermediate heat exchanger 1 23 and an intermediate heat exchanger 2 24. The solar heat collection system includes a solar collector 25, a water pump 3 26, a water pump 4 27, a valve 2 28, a water pump 5 29 and a hot water supply device 30. Specifically:

[0039] like Figure 1 As shown, the inlet of the compressor 1 is connected to the interface pipes of the evaporator 9 and the plate heat exchanger 11 through the gas-liquid separator 12, the outlet of the compressor 1 is connected to the interface pipe of the condenser 3 through the multi-way valve 2, the outlet of the drying filter 6 is connected to the inlet of the plate heat exchanger 17, and the outlet of the plate heat exchanger 17 is divided into two routes: one is the main route, which is connected to the inlet of the evaporator 9 and the plate heat exchanger 11 through the throttle valve 18, and the other is the supplementary route, which is connected to the air supply port of the compressor 1 through the throttle valve 13, the plate heat exchanger 17, and the valve 14. The above-mentioned compressor 1 can be any form of a fixed-frequency compressor with air supply and enthalpy increase function, a variable speed compressor, or a digital scroll compressor;

[0040] The expansion water tank 17 is connected to the condenser 3 through a pipeline and a water pump 19. The inlet and outlet of the fan coil 18 are connected to the expansion water tank 17 through a pipeline, and a water pump 20 is provided on the connecting pipeline between the fan coil 18 and the expansion water tank 17. The fan coil 18 is generally arranged in a room 21 of a building. The evaporator 9 is connected to the evaporating fan 10, and the evaporator 9 and the evaporating fan 10 are connected to the air duct of the room 21 through an air duct. Based on this, the evaporator 9, the evaporating fan 10 and the room 21 are connected to form a closed-loop circulation air duct. The control end of the evaporator 9 and the evaporating fan 10 is generally located in the room 21;

[0041] The hot water storage tank 22 is provided with an intermediate heat exchanger 1 23 and an intermediate heat exchanger 2 24. The inlet and outlet of the solar collector 25 are connected to the outlet and inlet of the intermediate heat exchanger 1 23 through pipes, and a water pump 3 26 is provided on the connecting pipe between the solar collector 25 and the intermediate heat exchanger 1 23; the outlet and inlet of the intermediate heat exchanger 2 24 are connected to the inlet and outlet on the same side of the plate heat exchanger 2 11 through pipes, and a water pump 5 29 is provided on the connecting pipe between the intermediate heat exchanger 2 24 and the plate heat exchanger 2 11. The outlet and inlet of the hot water storage tank 22 are connected to the inlet and outlet of the hot water supply device 30 through pipes, and a valve 2 28 and a water pump 4 27 are provided on the connecting pipe between the hot water storage tank 22 and the hot water supply device 30.

[0042] In this embodiment, the multi-way valve 2 connected to the outlet of the compressor 1 is preferably a four-way valve, and the gas-liquid separator 12 and the evaporator 9, as well as the gas-liquid separator 12 and the plate heat exchanger 11, can also be connected through the four-way valve, and the opening and closing of each pipeline can be controlled by the four-way valve.

[0043] In this embodiment, Figure 1 and Figure 2 As shown, preferably, a one-way valve 4 is provided on the pipeline connected to the inlet of the liquid storage tank 5, the pipeline connected to the evaporator 9, and the pipeline connected to the plate heat exchanger 11 to ensure the one-way operation of the refrigerant and avoid backflow.

[0044] In this embodiment, Figure 1 and Figure 2 As shown, preferably, a solenoid valve 15 and a solenoid valve 2 16 are respectively provided on the pipeline connected to the refrigerant inlet of the evaporator 9 and the pipeline connected to the refrigerant inlet of the plate heat exchanger 2 11 to control the circulation of the refrigerant.

[0045] In this embodiment, the condenser 3 can be any structure of a shell and tube heat exchanger or a plate heat exchanger; the evaporator 9 can be any structure of a parallel flow heat exchanger or a fin tube heat exchanger; the intermediate heat exchanger 1 23 and the intermediate heat exchanger 2 24 are preferably coil heat exchangers; the solar collector 25 can be any structure of a trough type or a flat plate type. The evaporating fan 10 can be any form of a variable frequency fan, a fixed frequency fan, or a variable speed fan; the throttle valve 1 8 and the throttle valve 2 13 can be any throttling mechanism form of a thermal expansion valve, an electronic expansion valve, a manual expansion valve, a flow-blocking expansion valve, or a floating ball expansion valve; the water pump 1 19, the water pump 2 20, the water pump 3 26, the water pump 4 27, and the water pump 5 29 can be any form of a positive displacement water pump or a vane pump.

[0046] The heating method of the solar heat pump heating system 100 based on quasi-two-stage compression is as follows:

[0047] (I) Refrigerant side circulation mode: The high-temperature and high-pressure gas from the compressor 1 passes through the multi-way valve 2 and enters the condenser 3. After being cooled by the condenser 3 into a low-temperature and high-pressure liquid, it passes through the liquid storage tank 5 and the drying filter 6 and enters the plate heat exchanger 1 7 in turn. It is then divided into two routes: the main route passes through the throttle valve 1 8 and becomes a low-temperature and low-pressure liquid. It then enters the evaporator 9 and the plate heat exchanger 2 11 to evaporate and absorb heat to become a superheated gas. It then passes through the gas-liquid separator 12 and enters the compressor 1 for compression. The other supplementary route passes through the throttle valve 2 13 and enters the plate heat exchanger 1 7 again. It finally returns to the air supply opening of the compressor 1 and enters the compressor 1, and the cycle is repeated in sequence. Figure 1 and Figure 2As shown, in order to ensure the correct flow direction of the refrigerant, a one-way valve 4 is also provided on the pipeline from the condenser 3 to the liquid storage tank 5.

[0048] (II) Water-side circulation mode of fan coil unit 18: The circulating water in expansion water tank 17 exchanges heat with high-temperature and high-pressure refrigerant in condenser 3 through water pump 1 19, and the circulating water heated by heat exchange enters expansion water tank 17 and circulates in sequence. At the same time, the high-temperature circulating water enters fan coil unit 18 through water pump 2 20, exchanges heat with return air in room 21, and the air heated by heat exchange is sent to room 21.

[0049] (III) Solar collector 25 water side circulation mode: After being heated by the solar collector 25, the circulating water enters the intermediate heat exchanger 1 23 in the hot water storage tank 22, exchanges heat with the circulating water in the hot water storage tank 22 and cools down, then returns to the solar collector 25 through the water pump 3 26, and circulates in sequence. After the circulating water in the intermediate heat exchanger 2 24 exchanges heat with the circulating water in the hot water storage tank 22 and heats up, it exchanges heat with the refrigerant in the plate heat exchanger 2 11 through the water pump 5 29 and cools down. At the same time, the circulating water in the hot water storage tank 22 passes through the water pump 4 27 and the valve 2 28 and flows into the hot water supply device 30 to provide domestic water.

[0050] (IV) Evaporator 9 air side circulation mode: The return air from room 21 is cooled and dehumidified after passing through evaporator 9, and the circulating air after dehumidification is sent back to room 21 by evaporator fan 10.

[0051] (V) Air circulation mode of the fan coil unit 18: The return air from the room 21 is heated after passing through the fan coil unit 18, and the heated circulating air is sent to the room 21 for heating.

[0052] The solar heat pump heating system 100 and heating method based on quasi-two-stage compression proposed in the present invention are novel in conception and ingenious in unit design optimization. Compared with the prior art, they have the following advantages and outstanding effects:

[0053] (1) In the existing solar heat pump system, the compressor exhaust temperature is too high under ultra-low temperature environment, resulting in a significant attenuation of the system heat exchange and COP of the solar heat pump system, and the system cannot continue to operate efficiently. The system of the present invention adopts an air-injection enthalpy-increasing compressor to effectively increase the condensation heat exchange. The air-injection technology can effectively reduce the compressor exhaust temperature, and realize efficient and stable operation of the system under ultra-low temperature and large temperature range variable working conditions.

[0054] (2) The simultaneous installation of an air-supplying and heat-increasing compressor and a heat storage tank can effectively increase the condensation heat exchange capacity, thereby obtaining circulating air with a higher temperature;

[0055] (3) Using solar energy as an auxiliary heat source can increase the evaporation temperature of the heat pump system, thereby improving the efficiency of the entire solar heat pump heating system. While providing efficient heating, it can also achieve an uninterrupted supply of domestic hot water;

[0056] (4) The system adopts multiple heat exchangers, which can effectively reduce the humidity of the circulating air;

[0057] (5) The coupling of solar thermal collection technology and quasi-two-stage compression heat pump technology realizes the complementary advantages of the two systems. It not only solves the key technical problem of the inability to continuously, stably and efficiently provide heat when using solar energy as a single heat source, but also solves the existing solar heat pump system's problems of excessively high compressor exhaust temperature, greatly reduced heating capacity and COP, and the inability of the system to operate efficiently and stably for a long time under ultra-low temperature and large temperature difference environments. It improves the energy efficiency ratio of the entire solar heat pump heating system, extends the service life of the equipment, and improves the efficiency, reliability and economy of the solar heat pump unit's operation throughout the year.

[0058] It can be seen that the solar heat pump heating system 100 and its heating method based on quasi-two-stage compression proposed in the present invention combine solar thermal collection technology and quasi-two-stage compression heat pump technology, which can make the entire heating system more efficient and stable. The heat pump system has a wide adjustable range of operating parameters and flexible and convenient control, while the solar thermal collection system has deficiencies such as intermittent and instability. Therefore, the present invention uses the solar thermal collection system as an auxiliary heat source, which can not only overcome the deficiencies such as low solar energy density and unstable heat collection, effectively improve the utilization rate of solar energy resources, but also improve the thermal performance of the heat pump system, improve its COP, and achieve the complementary advantages of the two systems. The operating parameters can be automatically adjusted to adapt to changes in environmental parameters to ensure efficient and reliable heating and heating of the system. The present invention combines the large temperature difference and variable working condition characteristics of the solar-quasi-two-stage compression heat pump system, which is expected to further improve the operating reliability and adaptability of the heating system under different climatic conditions, promote the overall improvement of system performance and economic benefits, and further promote the application scope of the solar heat pump heating system.

[0059] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A solar heat pump heating system based on quasi-two-stage compression, characterized in that: It includes a quasi-two-stage compression heat pump system and a solar heat collection system. The quasi-two-stage compression heat pump system includes a compressor, a condenser, a liquid storage tank, a drying filter, a plate heat exchanger 1, an evaporator, an evaporating fan, a plate heat exchanger 2, a gas-liquid separator, an expansion water tank, a fan coil, a water pump 1, a water pump 2, a hot water storage tank, an intermediate heat exchanger 1 and an intermediate heat exchanger 2. The solar heat collection system includes a solar collector, a water pump 3, a water pump 4, a water pump 5 and a hot water supply device, wherein: The inlet of the compressor is connected to the interface pipes of the evaporator and the plate heat exchanger 2 through the gas-liquid separator, the outlet of the compressor is connected to the interface pipe of the condenser through a multi-way valve, the outlet of the drying filter is connected to the inlet of the plate heat exchanger 1, and the outlet of the plate heat exchanger 1 is divided into two routes: one route is connected to the inlet of the evaporator and the plate heat exchanger 2 through the throttle valve 1, and the other route is connected to the air supply port of the compressor through the throttle valve 2, the plate heat exchanger 1, and the valve 1; the compressor is an air supply enthalpy increase compressor; The expansion water tank is connected to the condenser through a pipeline and the first water pump, the inlet and outlet of the fan coil are connected to the expansion water tank through a pipeline, and the second water pump is arranged on the connecting pipeline between the fan coil and the expansion water tank, and the fan coil is arranged in the room; the evaporator is connected to the evaporation fan, and the evaporator and the evaporation fan are connected to the air duct of the room through an air duct; The intermediate heat exchanger 1 and the intermediate heat exchanger 2 are arranged inside the heat storage tank, the inlet and outlet of the solar collector are connected to the outlet and inlet of the intermediate heat exchanger 1 through pipes, and the water pump 3 is arranged on the connecting pipe between the solar collector and the intermediate heat exchanger 1; the outlet and inlet of the intermediate heat exchanger 2 are connected to the inlet and outlet of the plate heat exchanger 2 through pipes, and the water pump 5 is arranged on the connecting pipe between the intermediate heat exchanger 2 and the plate heat exchanger 2; the outlet and inlet of the heat storage tank are connected to the inlet and outlet of the hot water supply device through pipes, and the valve 2 and the water pump 4 are arranged on the connecting pipe between the heat storage tank and the hot water supply device.

2. The solar heat pump heating system based on quasi-two-stage compression according to claim 1 is characterized in that: The air-inflation and heat-increasing compressor is a fixed-frequency compressor with an air-inflation and heat-increasing function, a variable-speed compressor with an air-inflation and heat-increasing function, or a digital scroll compressor with an air-inflation and heat-increasing function.

3. The solar heat pump heating system based on quasi-two-stage compression according to claim 1 is characterized in that: The multi-way valve is a four-way valve, the gas-liquid separator is connected to the evaporator through the four-way valve, and the gas-liquid separator is connected to the second plate heat exchanger through the four-way valve.

4. The solar heat pump heating system based on quasi-two-stage compression according to claim 1 is characterized in that: The refrigerant inlet of the evaporator and the refrigerant inlet of the second plate heat exchanger are respectively provided with a first solenoid valve and a second solenoid valve.

5. The solar heat pump heating system based on quasi-two-stage compression according to any one of claims 1 to 4, characterized in that: The condenser is a shell and tube heat exchanger or a plate heat exchanger; the evaporator is a parallel flow heat exchanger or a fin-tube heat exchanger; the intermediate heat exchanger 1 and the intermediate heat exchanger 2 are coil heat exchangers; the solar collector is a trough solar collector or a flat plate solar collector.

6. The solar heat pump heating system based on quasi-two-stage compression according to any one of claims 1 to 4, characterized in that: The evaporation fan is a variable frequency fan, a fixed frequency fan or a speed regulating fan.

7. The solar heat pump heating system based on quasi-two-stage compression according to any one of claims 1 to 4, characterized in that: The throttle valve 1 and the throttle valve 2 are any one of a thermal expansion valve, an electronic expansion valve, a manual expansion valve, a choke expansion valve and a float expansion valve.

8. The solar heat pump heating system based on quasi-two-stage compression according to any one of claims 1 to 4, characterized in that: The water pump one, the water pump two, the water pump three, the water pump four and the water pump five are all volumetric water pumps or vane pumps.

9. A heating method of a solar heat pump heating system based on quasi-two-stage compression according to any one of claims 1 to 8, characterized in that: include: Refrigerant side circulation mode: the high-temperature and high-pressure gas from the compressor enters the condenser through the multi-way valve, and after being cooled into a low-temperature and high-pressure liquid by the condenser, it passes through the liquid storage device and the drying filter in sequence and enters the plate heat exchanger 1, and then is divided into two paths: one path passes through the throttle valve 1 to become a low-temperature and low-pressure liquid, and then enters the evaporator and the plate heat exchanger 2 to evaporate and absorb heat to become a superheated gas, and then enters the compressor through the gas-liquid separator for compression; the other path passes through the throttle valve 2 and enters the plate heat exchanger 1 again, and then enters the compressor through the air supply opening of the compressor; Fan coil water side circulation mode: the circulating water in the expansion water tank passes through the water pump 1 to perform heat exchange with the high-temperature and high-pressure refrigerant in the condenser, and the circulating water heated by heat exchange enters the expansion water tank; at the same time, the circulating water heated by heat exchange passes through the water pump 2 to enter the fan coil and perform heat exchange with the return air in the room; Solar collector water side circulation mode: After the circulating water is heated by the solar collector, it enters the intermediate heat exchanger 1 to exchange heat with the circulating water in the hot water storage tank, and then returns to the solar collector through the water pump 3; after the circulating water in the intermediate heat exchanger 2 exchanges heat with the circulating water in the hot water storage tank, it exchanges heat with the refrigerant in the plate heat exchanger 2 through the water pump 5; at the same time, the circulating water in the hot water storage tank flows into the hot water supply device through the water pump 4 and the valve 2 to provide domestic water; Evaporator air side circulation mode: the room return air is cooled and dehumidified after passing through the evaporator, and the circulating air after dehumidification is sent back to the room by the evaporator fan; Fan coil air side circulation mode: the room return air is heated after passing through the fan coil, and the heated circulating air is sent into the room for heating.

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