Solar energy coupled jet-main circulation system and control method

Abstract

The application belongs to the technical field of solar energy coupling jet-main cycle, and provides a solar energy coupling jet-main cycle system and a control method. According to the solar radiation intensity and scene demand, the solar energy direct heating mode, the solar energy coupling jet heating mode and / or the CO2 double-stage compression cycle heating mode are coupled to enter the combined working mode, so that the best working condition is ensured in the variable environment, and the maximum heating capacity is obtained with the minimum energy consumption. Through reasonable allocation of multiple working conditions, the application realizes multiple modes such as solar energy heating, CO2 double-stage compression heating, solar energy jet heating, solar energy jet CO2 coupling heating and the like.

Description

Technical Field

[0001] This invention belongs to the field of solar coupled jet-main circulation technology, specifically relating to a solar coupled jet-main circulation system and control method. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Air source heat pumps based on vapor compression cycles have become the most suitable method for promotion due to their advantages of high efficiency, energy saving, and cost-effectiveness, and have been widely used in many regions. However, when used in cold regions, air source heat pumps face challenges such as low ambient temperature, large intake specific volume, small system working fluid circulation volume, high pressure ratio, high exhaust temperature, poor lubrication, and frost formation on the evaporator surface, which limit their widespread application.

[0004] Existing technologies mainly include solar-assisted CO2 single-stage compression heat pump systems, solar CO2 cascade heat pump systems, solar thermal driven CO2 jet compression mixing systems, and direct expansion solar CO2 heat pump systems. These existing technologies suffer from low solar energy utilization and limited control strategies. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a solar-coupled jet-main-cycle system and its control method. This invention can achieve optimal operating conditions under varying environments, obtaining maximum heating capacity with minimal energy consumption. Furthermore, it utilizes CO2 as a refrigerant to overcome the problem of low refrigeration efficiency caused by excessive throttling losses in traditional vapor compression refrigeration, ensuring that temperature glide matches refrigeration demand. By working in conjunction with a radiative refrigeration system, it fully utilizes natural cold sources. The addition of a novel plate heat exchanger avoids energy waste caused by frequent start-stop cycles of jet refrigeration, further improving energy efficiency.

[0006] According to some embodiments, the present invention adopts the following technical solution: A solar-coupled jet-main circulation system includes a solar-coupled jet unit, a main circulation unit, and a water supply unit, wherein: The solar coupled jet unit includes a solar thermal panel, which is connected to a high-temperature hot water storage tank. The high-temperature hot water storage tank is connected to a steam generator. The steam generator is connected to a condenser through an ejector. One end of the condenser is connected to an intermediate heat exchanger, which connects the steam generator and an auxiliary evaporator. The main circulation unit includes a low-pressure compressor, a high-pressure compressor, a gas cooler, an interstage heat exchanger, and a mixing chamber. One end of the mixing chamber is connected to the high-pressure compressor through a second gas-liquid separator. The high-pressure compressor is connected to the gas cooler. The gas cooler is also connected to the auxiliary evaporator. The interstage heat exchanger is connected to the low-pressure compressor through a user heat exchange device and a first gas-liquid separator. The water supply unit includes a medium-temperature hot water storage tank and a plate heat exchanger. One end of the medium-temperature hot water storage tank is connected to a condenser, and the other end is connected to a high-temperature hot water storage tank and a plate heat exchanger via pipelines. The plate heat exchanger is connected to the low-pressure compressor and the other end of the mixing chamber. An expansion valve or solenoid valve is installed on the connecting pipeline; When the solar radiation intensity is greater than the set value, the solar collector panel has sufficient heat and enters the direct solar heating mode. When the solar radiation intensity is less than the set value, the heat stored in the high-temperature hot water storage tank provides heat to the steam generator, which in turn provides heat to the carbon dioxide working fluid of the solar thermal injection unit, thus entering the solar coupled injection heating mode. When the solar radiation intensity is less than the set value and the heat source stored in the high-temperature hot water storage tank has been exhausted, the main circulation unit provides heat and enters the CO2 two-stage compression cycle heating mode. Depending on the solar radiation intensity and scenario requirements, the solar direct heating mode, the solar coupled jet heating mode, and / or the CO2 two-stage compression cycle heating mode are coupled to enter a joint working mode, so as to ensure that the best working conditions are achieved in the variable environment and obtain the maximum heat output with the minimum energy consumption.

[0007] As an alternative implementation, a first water pump is installed on the connecting pipe between the solar thermal panel and the high-temperature hot water storage tank; a second water pump is installed on the connecting pipe between the high-temperature hot water storage tank and the steam generator; a first electronic expansion valve is installed between the intermediate heat exchanger and the auxiliary evaporator; a first solenoid valve is installed on the connecting pipe between the high-temperature hot water storage tank and the gas cooler; and a refrigerant pump is connected between the steam generator and the intermediate heat exchanger. One end of the interstage heat exchanger is connected to a second electronic expansion valve, and the other end of the interstage heat exchanger is connected to the user heat exchange device. A third electronic expansion valve is installed on the connecting pipe. A second solenoid valve and a third solenoid valve are installed on the connecting pipe between the interstage heat exchanger and the intermediate heat exchanger. A fifth solenoid valve is installed on the connecting pipe between the medium-temperature hot water storage tank and the high-temperature hot water storage tank, a sixth solenoid valve is installed on the connecting pipe between the medium-temperature hot water storage tank and the plate heat exchanger, and a third water pump is installed between the condenser and the medium-temperature hot water storage tank.

[0008] The control method based on the above system includes the following steps: When the solar radiation intensity is greater than the set value, the solar collector panel has sufficient heat and enters the direct solar heating mode. When the solar radiation intensity is less than the set value, the heat stored in the high-temperature hot water storage tank provides heat to the steam generator, which in turn provides heat to the carbon dioxide working fluid of the solar thermal injection unit, thus entering the solar coupled injection heating mode. When the solar radiation intensity is less than the set value and the heat source stored in the high-temperature hot water storage tank has been exhausted, the main circulation unit provides heat and enters the CO2 two-stage compression cycle heating mode. Depending on the solar radiation intensity and scenario requirements, the solar direct heating mode, the solar coupled jet heating mode, and / or the CO2 two-stage compression cycle heating mode are coupled to enter a joint working mode, so as to ensure that the best working conditions are achieved in the variable environment and obtain the maximum heat output with the minimum energy consumption.

[0009] As an optional implementation method, the process of entering the solar coupled jet heating mode includes: when the solar radiation intensity is greater than the set value, resulting in sufficient heat from the solar collector, the high-temperature hot water storage tank is used to directly supply heat, the first solenoid valve is opened, the other solenoid valves are closed, the solar collector absorbs heat into the high-temperature hot water storage tank for heat storage, and then enters the gas cooler through the first solenoid valve to supply heat to the user.

[0010] As an optional implementation, the process of entering the solar coupled jet heating mode includes: when solar radiation is less than a set value, resulting in insufficient heat from the solar collector, solar coupled jet heating is used. When the high-temperature hot water storage tank stores heat to provide heat to the steam generator, the first electronic expansion valve opens, while the other electronic expansion valves and solenoid valves close. The high-temperature hot water storage tank provides heat to the working fluid, which enters the steam generator through pipelines to provide heat to the CO2 working fluid of the solar thermal jet unit, making it into a high-temperature and high-pressure superheated state. After releasing heat, the working fluid returns to the high-temperature hot water storage tank for reheating. The high-temperature and high-pressure CO2 flowing out of the steam generator enters the jet chamber of the ejector, entrains the low-temperature and low-pressure working fluid from the auxiliary evaporator, mixes it, and discharges it to the condenser. The liquid working fluid is cooled and depressurized by the first electronic expansion valve, absorbs heat in the auxiliary evaporator, and returns to the ejector. The gaseous working fluid returns to the steam generator through the fluorine pump.

[0011] As an optional implementation, the process of entering the CO2 two-stage compression cycle heating mode includes: when solar radiation is less than a set value, the solar collector cannot provide heat at all, and the heat source stored in the high-temperature hot water storage tank is exhausted, the high-temperature medium-pressure superheated gaseous refrigerant from the low-pressure compressor outlet enters one end of the mixing chamber and mixes with the medium-temperature medium-pressure gaseous and liquid refrigerant entering the upper end of the mixing chamber. The saturated gaseous refrigerant then flows out from the other end of the mixing chamber and enters the second gas-liquid separator. From the second gas-liquid separator, it reaches the high-pressure compressor, where, under the action of the high-pressure compressor, the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature high-pressure superheated gaseous refrigerant. The high-temperature high-pressure superheated gaseous refrigerant enters the gas cooler, where it is cooled by the hot water circulation loop to become a medium-temperature high-pressure refrigerant. One refrigerant path directly enters the upper inlet of one side of the interstage heat exchanger, while another path is throttled by the second electronic expansion valve to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant, which then enters the lower inlet of one side of the interstage heat exchanger. The two refrigerant paths then exchange heat in the interstage heat exchanger. The medium-temperature, medium-pressure refrigerant entering the upper inlet of one side of the interstage heat exchanger enters the third electronic expansion valve through the lower outlet of one side. The other path, a medium-temperature, medium-pressure gaseous and liquid mixed refrigerant entering the lower inlet of the other side of the interstage heat exchanger, enters the mixing chamber through the upper right outlet, where it mixes with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor. The refrigerant entering the third electronic expansion valve is throttled from medium-temperature, medium-pressure to low-temperature, low-pressure, and then enters the user's heat exchange device for heating. After absorbing heat, the refrigerant changes from low-temperature, low-pressure to medium-temperature, low-pressure and enters the low-pressure compressor side.

[0012] As an optional implementation method, the process of entering the solar direct heating combined with solar coupled jet heating mode includes: when the solar radiation is greater than the set value, resulting in sufficient heat on the solar collector, the high-temperature hot water storage tank direct heating and solar coupled jet heating operate simultaneously. The solar collector absorbs heat into the high-temperature storage tank for heat storage and then enters the gas cooler through the first solenoid valve to provide heat to the user. When the high-temperature hot water storage tank stores heat to provide heat to the steam generator, it also provides heat to the working fluid. This heat is then introduced into the steam generator through pipelines to provide heat to the CO2 working fluid, causing it to become a superheated state under high temperature and pressure. After releasing heat, the working fluid returns to the high-temperature hot water storage tank for reheating.

[0013] As an alternative implementation method, the process of entering the solar direct heating combined with CO2 two-stage compression cycle heating mode includes: When solar radiation is strong, resulting in sufficient heat from the solar collectors, the system operates simultaneously with direct heating from a high-temperature hot water storage tank and a dual-pressure circulation system. Heat is absorbed by the solar collectors and stored in the high-temperature storage tank before passing through a first solenoid valve and entering a gas cooler to supply heat to users. High-temperature, medium-pressure superheated gaseous refrigerant from the low-pressure compressor outlet enters one inlet of the mixing chamber and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber. Saturated gaseous refrigerant flows out from the other end of the mixing chamber and enters the second gas-liquid separator. From the second gas-liquid separator, it reaches the high-pressure compressor, where it transforms from a medium-pressure saturated gaseous refrigerant into a high-temperature, high-pressure superheated gaseous refrigerant. This high-temperature, high-pressure superheated gaseous refrigerant then enters the gas cooler, where it is cooled by the hot water circulation loop to become a medium-temperature, high-pressure refrigerant. After cooling, the medium-temperature, high-pressure refrigerant enters directly into the upper inlet of one side of the interstage heat exchanger, while the other path is throttled by the second electronic expansion valve to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant, which then enters the lower inlet of the other side of the interstage heat exchanger. The two refrigerants then exchange heat in the interstage heat exchanger. The medium-temperature, medium-pressure refrigerant entering the upper inlet of one side of the interstage heat exchanger enters the third electronic expansion valve through the lower left outlet, while the other medium-temperature, medium-pressure gaseous and liquid mixed refrigerant entering the lower inlet of one side of the interstage heat exchanger enters the mixing chamber through the upper right outlet, mixing with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor. The refrigerant entering the third electronic expansion valve is throttled from medium-temperature, medium-pressure to low-temperature, low-pressure, and then enters the user's heat exchange device for heating. After absorbing heat, the refrigerant changes from low-temperature, low-pressure to medium-temperature, low-pressure and enters the low-pressure compressor.

[0014] As an optional implementation, the process of entering the solar coupled jet combined with CO2 two-stage compression cycle heating mode includes: when the solar radiation is less than the set value, causing the solar collector to be unable to provide heat at all, and the heat source stored in the high-temperature hot water storage tank is exhausted, solar coupled jet and two-stage compression cycle are used for heating. When the heat stored in the high-temperature hot water storage tank provides heat to the steam generator, the high-temperature hot water storage tank provides heat to the working fluid, which enters the steam generator through the pipeline to provide heat to the CO2 working fluid, making it into a high-temperature and high-pressure superheated state. After releasing heat, the working fluid returns to the high-temperature hot water storage tank for reheating. High-temperature, high-pressure CO2 flowing from the steam generator enters the ejector chamber of the ejector, entraining the low-temperature, low-pressure working fluid from the auxiliary evaporator. The mixture is then discharged to the condenser. The liquid working fluid, after being cooled and depressurized by the first electronic expansion valve, absorbs heat in the auxiliary evaporator and returns to the ejector. The gaseous working fluid returns to the steam generator via the refrigerant pump for the next cycle. High-temperature, medium-pressure superheated gaseous refrigerant from the low-pressure compressor outlet enters the left inlet of the mixing chamber and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber. The saturated gaseous refrigerant then flows out from one end of the mixing chamber and enters the second gas-liquid separator. From the second gas-liquid separator, it reaches the high-pressure compressor. Under the action of the high-pressure compressor, the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. This high-temperature, high-pressure superheated gaseous refrigerant enters the gas cooler, where it is heated. The water circulation loop cools the medium-temperature, high-pressure refrigerant. The cooled medium-temperature, high-pressure refrigerant enters directly into the upper inlet of one side of the interstage heat exchanger, while the other path is throttled by the second electronic expansion valve to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant, which then enters the lower inlet of the other side of the interstage heat exchanger. The two refrigerants then exchange heat in the interstage heat exchanger. The medium-temperature, medium-pressure refrigerant entering the upper inlet of one side of the interstage heat exchanger enters the third electronic expansion valve through the lower left outlet. The other path, the medium-temperature, medium-pressure gaseous and liquid mixed refrigerant entering the lower inlet of the other side of the interstage heat exchanger, enters the mixing chamber through the upper right outlet, mixing with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor. The refrigerant entering the third electronic expansion valve is throttled from medium-temperature, medium-pressure to low-temperature, low-pressure, and then enters the user's heat exchange device for heating. After absorbing heat, the refrigerant changes from low-temperature, low-pressure to medium-temperature, low-pressure and enters the low-pressure compressor.

[0015] As an alternative implementation method, the process of entering the combined heating mode of direct solar power supply, coupled injection and CO2 two-stage compression cycle includes: the solar collector absorbs heat into the high-temperature heat storage box for heat storage, and then enters the gas cooler through the first solenoid valve to provide heat to the user. The high-temperature hot water storage tank provides heat to the working fluid, which enters the steam generator through pipelines to provide heat to the CO2 working fluid, making it into a superheated state with high temperature and high pressure. After releasing heat, the working fluid returns to the high-temperature hot water storage tank for reheating. The high-temperature, high-pressure CO2 flowing out of the steam generator enters the ejector chamber, entrains the low-temperature, low-pressure working fluid from the auxiliary evaporator, mixes and is discharged to the condenser. The liquid working fluid is cooled and depressurized by the first electronic expansion valve, absorbs heat in the auxiliary evaporator, and returns to the ejector. The gaseous working fluid is returned to the steam generator by the fluorine pump for the next cycle. The high-temperature, medium-pressure superheated gaseous refrigerant exiting the low-pressure compressor enters one inlet of the mixing chamber and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber. The saturated gaseous refrigerant then flows out from one outlet of the mixing chamber and enters the second gas-liquid separator. From the second gas-liquid separator, it reaches the high-pressure compressor. Under the action of the high-pressure compressor, the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. This high-temperature, high-pressure superheated gaseous refrigerant enters the gas cooler, where it is cooled by the hot water circulation loop to become a medium-temperature, high-pressure refrigerant. The cooled medium-temperature, high-pressure refrigerant then enters either directly at the upper inlet of one side of the interstage heat exchanger or is throttled by the second electronic expansion valve to become... The low-temperature, medium-pressure gaseous and liquid refrigerant mixture then enters the other lower inlet of the interstage heat exchanger. The two refrigerants then exchange heat in the interstage heat exchanger. The medium-temperature, medium-pressure refrigerant entering the upper inlet on one side of the interstage heat exchanger enters the third electronic expansion valve through the lower left outlet. The other medium-temperature, medium-pressure gaseous and liquid refrigerant entering the other lower inlet of the interstage heat exchanger enters the mixing chamber through the upper right outlet, mixing with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor. The refrigerant entering the third electronic expansion valve is throttled from medium-temperature, medium-pressure to low-temperature, low-pressure, and then enters the user's heat exchange device for heating. After absorbing heat, the refrigerant changes from low-temperature, low-pressure to medium-temperature, low-pressure and enters the low-pressure compressor.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention achieves optimal operating conditions in varying environments, maximizing heating capacity with minimal energy consumption. It utilizes CO2 as a refrigerant to overcome the low refrigeration efficiency caused by excessive throttling losses in traditional vapor compression refrigeration, ensuring that temperature glide matches refrigeration demand. By working in conjunction with a radiant refrigeration system, it fully utilizes natural cold sources. In this embodiment, a novel plate heat exchanger is incorporated to avoid energy waste caused by frequent start-stop cycles of jet refrigeration, further improving energy efficiency.

[0017] This invention employs CO2 two-stage compression technology and is equipped with an interstage heat exchanger to effectively reduce exhaust pressure and improve cycle thermal efficiency.

[0018] This invention employs interstage injection technology to reduce heat loss in intermediate heat exchange stages.

[0019] This invention uses solar water heating and heat storage to collect solar energy, effectively avoiding the problem of pressure leakage in the collector.

[0020] This invention adds an intermediate hot water storage tank and, through reasonable allocation of various operating conditions, realizes multiple modes such as solar heating, CO2 two-stage compression heating, solar jet heating, and solar jet CO2 coupled heating.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0023] Figure 1 This is a schematic diagram of a solar coupled jet-main circulation system according to one embodiment. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0026] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0027] Where there is no conflict, the embodiments and features described in this application may be combined with each other.

[0028] Example 1 Solar coupled jet-main circulation system, such as Figure 1As shown, the system includes a solar-coupled injection unit (A), comprising a solar thermal panel (1), a high-temperature hot water storage tank (2), a steam generator (3), an ejector (4), a condenser (5), an intermediate heat exchanger (6), an auxiliary evaporator (7), a refrigerant pump (8), a first water pump (9), a second water pump (10), a first electronic expansion valve (11), and a first solenoid valve (12) arranged sequentially on the circulation pipeline, which are connected by pipelines to form a circulation; and a main circulation unit (B), comprising a low-pressure compressor (13) and a high-pressure compressor (14). The gas cooler (15), interstage heat exchanger (16), mixing chamber (17), first gas-liquid separator (18), second gas-liquid separator (19), user heat exchange device (20), second electronic expansion valve (21), third electronic expansion valve (22), second solenoid valve (23) and third solenoid valve (24) are connected by pipes to form a circulation; the water supply unit (C) includes a medium-temperature hot water storage tank (25), plate heat exchanger (26), third water pump (27), fourth solenoid valve (28), fifth solenoid valve (29), sixth solenoid valve (30) and seventh solenoid valve (31) are connected by pipes to form a circulation.

[0029] A first water pump (9) is installed on the connecting pipe between the solar thermal panel (1) and the high-temperature hot water storage tank (2); a second water pump (10) is installed on the connecting pipe between the high-temperature hot water storage tank (2) and the steam generator; a first electronic expansion valve (11) is installed between the intermediate heat exchanger (6) and the auxiliary evaporator (7); a first solenoid valve (12) is installed on the connecting pipe between the high-temperature hot water storage tank (2) and the gas cooler (15); and a fluorine pump (8) is connected between the steam generator (3) and the intermediate heat exchanger (6). One end of the interstage heat exchanger (16) is connected to a second electronic expansion valve (21), and the other end of the interstage heat exchanger (16) is connected to the user heat exchange device (20). A third electronic expansion valve (22) is provided on the connecting pipe. A second solenoid valve (23) and a third solenoid valve (24) are provided on the connecting pipe between the interstage heat exchanger (16) and the intermediate heat exchanger (6). A fifth solenoid valve (29) is installed on the connecting pipe between the medium-temperature hot water storage tank (25) and the high-temperature hot water storage tank (2), a sixth solenoid valve (30) is installed on the connecting pipe between the medium-temperature hot water storage tank (25) and the plate heat exchanger (26), and a third water pump (27) is installed between the condenser (5) and the medium-temperature hot water storage tank (25).

[0030] The control methods of the above system operate in different modes, specifically as follows: Operating mode 1: Direct solar heating mode.

[0031] When solar radiation is strong and the solar collector (1) has sufficient heat, the high-temperature hot water storage tank (2) directly supplies heat. The first solenoid valve (12) is opened and the other solenoid valves are closed. The solar collector (1) absorbs heat into the high-temperature hot water storage tank (2) for heat storage and then enters the gas cooler (15) through the first solenoid valve (12) to supply heat to the user.

[0032] Operating Mode 2: Solar Coupled Jet Heating Mode When solar radiation is weak, resulting in insufficient heat from the solar collector (1), solar coupled jet heating is used. When the high-temperature hot water storage tank (2) stores heat to provide heat to the steam generator (3), the first electronic expansion valve (11) opens, and the remaining electronic expansion valves and solenoid valves close. The high-temperature hot water storage tank (2) provides heat to the working fluid, which enters the steam generator (3) through the pipeline to provide heat to the CO2 working fluid of the solar coupled jet unit (A), making it into a high-temperature and high-pressure superheated state. After releasing heat, the working fluid returns to the high-temperature hot water storage tank (2) for heating. The high-temperature and high-pressure CO2 flowing out of the steam generator (3) enters the jet chamber of the ejector (4), entrains the low-temperature and low-pressure working fluid from the auxiliary evaporator (7), mixes and discharges to the condenser (5). The liquid working fluid is cooled and depressurized by the first electronic expansion valve (11), absorbs heat in the auxiliary evaporator (7), and returns to the ejector (4). The gaseous working fluid returns to the steam generator (3) through the fluorine pump (8) for the next cycle.

[0033] Operating Mode 3: CO2 Two-Stage Compression Cycle Heating Mode When solar radiation is weak, causing the solar collector (1) to be unable to provide heat at all, and the heat source stored in the high-temperature hot water storage tank (2) is exhausted, requiring the main circulation unit (B) to provide heat, the high-temperature medium-pressure superheated gaseous refrigerant from the outlet of the low-pressure compressor (13) enters the left inlet of the mixing chamber (17) and mixes with the medium-temperature medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber (17). The saturated gaseous refrigerant flows out from the right outlet of the mixing chamber (17) and enters the second gas-liquid separator (18). The second gas-liquid separator exits to the high-pressure compressor (14), and under the action of the high-pressure compressor (14), the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature high-pressure superheated gaseous refrigerant. The high-temperature high-pressure superheated gaseous refrigerant enters the gas cooler (15), where it is cooled by the hot water circulation loop to become a medium-temperature high-pressure refrigerant. The cooled medium-temperature high-pressure refrigerant then directly enters the stage. One path of refrigerant enters the upper left inlet of the interstage heat exchanger (16), which is throttled by the second electronic expansion valve (21) to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant. This then enters the lower right inlet of the interstage heat exchanger (16). The two refrigerants then exchange heat in the interstage heat exchanger (16). The medium-temperature, medium-pressure refrigerant entering the upper left inlet of the interstage heat exchanger (16) enters the third electronic expansion valve (22) through the lower left outlet. The other path enters the lower right inlet of the interstage heat exchanger (16). The gaseous and liquid mixed refrigerant at medium and high temperature enters the mixing chamber (17) through the upper right outlet, mixes with the high temperature and medium pressure gaseous refrigerant discharged from the low-pressure compressor (13), and the refrigerant after entering the third electronic expansion valve (22) is throttled from medium temperature and medium pressure refrigerant to low temperature and low pressure refrigerant. Then it enters the user heat exchange device (20) for heating. After absorbing heat, the refrigerant changes from low temperature and low pressure refrigerant to medium temperature and low pressure and enters the left side of the low-pressure compressor (13).

[0034] Working Mode 4: Direct Solar Heating Combined with Solar Coupled Jet Heating Mode When solar radiation is strong, resulting in sufficient heat from the solar collector (1), the high-temperature hot water storage tank (2) directly supplies heat and the solar coupled jet operates simultaneously. The first electronic expansion valve (11) and the first solenoid valve (12) are open, while the remaining electronic expansion valves and solenoid valves are closed. The solar collector (1) absorbs heat into the high-temperature hot water storage tank (2) for heat storage, and then passes through the first solenoid valve (12) into the gas cooler (15) to supply heat to the user. When the high-temperature hot water storage tank (2) stores heat to provide heat to the steam generator (3), the high-temperature hot water storage tank (2) provides heat to the working fluid, which enters the steam generator (3) through the pipeline to provide heat to the CO2 working fluid of the jet refrigeration system, making it into a superheated state with high temperature and high pressure. After releasing heat, the working fluid returns to the high-temperature hot water storage tank (2) for reheating. In the jet refrigeration system: the high-temperature and high-pressure CO2 flowing out from the steam generator (3) enters the jet chamber of the ejector (4), entrains the low-temperature and low-pressure working fluid from the auxiliary evaporator (7), mixes and discharges to the condenser (5). The liquid working fluid is cooled and depressurized by the first electronic expansion valve (11), absorbs heat in the auxiliary evaporator (7), and returns to the ejector (4). The gaseous working fluid returns to the steam generator (3) through the fluorine pump (8) for the next cycle.

[0035] Operating Mode 5: Solar direct heating combined with CO2 two-stage compression cycle heating mode When solar radiation is strong, resulting in sufficient heat from the solar collector (1), the high-temperature hot water storage tank (2) directly supplies heat and operates in a dual-pressure circulation mode simultaneously. The first solenoid valve (12), the second solenoid valve (23), and the third solenoid valve (24) are opened, while the remaining solenoid valves are closed. The solar collector (1) absorbs heat into the high-temperature hot water storage tank (2) for heat storage, and then passes through the first solenoid valve (12) into the gas cooler (15) to supply heat to the user. The high-temperature medium-pressure superheated gaseous refrigerant from the outlet of the low-pressure compressor (13) enters the mixed... The refrigerant, which is a mixture of medium-temperature, medium-pressure gaseous and liquid refrigerant, enters the mixing chamber (17) through the left inlet and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber (17). The saturated gaseous refrigerant then flows out from the right outlet of the mixing chamber (17) and enters the second gas-liquid separator (18). From the second gas-liquid separator, the refrigerant flows to the high-pressure compressor (14). Under the action of the high-pressure compressor (14), the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. The high-temperature, high-pressure superheated gaseous refrigerant then enters the gas cooler (15) and is cooled by the gas cooler. The refrigerant in the heat exchanger (15) is cooled into a medium-temperature, high-pressure refrigerant by the hot water circulation loop. After cooling, the medium-temperature, high-pressure refrigerant enters the upper left inlet of the interstage heat exchanger (16) directly, and the other enters the lower right inlet of the interstage heat exchanger (16) through the second electronic expansion valve (21) to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant. The two refrigerants then exchange heat in the interstage heat exchanger (16). The medium-temperature, medium-pressure refrigerant that enters the upper left inlet of the interstage heat exchanger (16) enters the third electronic expansion valve (22) through the lower left outlet. Another path enters the medium-temperature and medium-pressure gaseous and liquid mixed refrigerant at the lower right inlet of the interstage heat exchanger (16) and enters the mixing chamber (17) through the upper right outlet. It mixes with the high-temperature and medium-pressure gaseous refrigerant discharged from the low-pressure compressor (13). The refrigerant after entering the third electronic expansion valve (22) is throttled from medium-temperature and medium-pressure refrigerant to low-temperature and low-pressure refrigerant. Then it enters the user heat exchange device (20) for heating. After absorbing heat, the refrigerant changes from low-temperature and low-pressure refrigerant to medium-temperature and low-pressure refrigerant and enters the left side of the low-pressure compressor (13).

[0036] Operating Mode Six: Solar Coupled Jet Combined with CO2 Two-Stage Compression Cycle Heating Mode When solar radiation is weak, causing the solar collector (1) to be unable to provide heat at all, and the heat source stored in the high-temperature hot water storage tank (2) is exhausted, heat is supplied by solar coupling injection and two-stage compression cycle. When the first solenoid valve (7) and the second solenoid valve (8) are closed and the remaining solenoid valves are open, the heat stored in the high-temperature hot water storage tank (2) provides heat to the steam generator (3). When the first electronic expansion valve (11) is opened and the remaining electronic expansion valves and solenoid valves are closed, the high-temperature hot water storage tank (2) provides heat to the working fluid, which enters the steam generator (3) through the pipeline to provide heat to the CO2 working fluid of the solar coupling injection unit (A), making it into a superheated state of high temperature and high pressure. After releasing heat, the working fluid returns to the high-temperature hot water storage tank (2) for heating. The high-temperature, high-pressure CO2 flowing out of the steam generator (3) enters the ejector chamber of the ejector (4), entrains the low-temperature, low-pressure working fluid from the auxiliary evaporator (7), mixes and is discharged to the condenser (5). The liquid working fluid is cooled and depressurized by the first electronic expansion valve (11), absorbs heat in the auxiliary evaporator (7), and returns to the ejector (4). The gaseous working fluid returns to the steam generator (3) via the refrigerant pump (8) for the next cycle. The high-temperature, medium-pressure superheated gaseous refrigerant from the outlet of the low-pressure compressor (13) enters the mixing chamber. The refrigerant, which is a mixture of medium-temperature, medium-pressure gaseous and liquid refrigerant, enters the mixing chamber (17) through the left inlet and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber (17). The saturated gaseous refrigerant then flows out from the right outlet of the mixing chamber (17) and enters the second gas-liquid separator (18). From the second gas-liquid separator, the refrigerant flows to the high-pressure compressor (14). Under the action of the high-pressure compressor (14), the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. The high-temperature, high-pressure superheated gaseous refrigerant then enters the gas cooler (15) and is cooled by the gas cooler. The refrigerant in the heat exchanger (15) is cooled into a medium-temperature, high-pressure refrigerant by the hot water circulation loop. After cooling, the medium-temperature, high-pressure refrigerant enters the upper left inlet of the interstage heat exchanger (16) directly, and the other enters the lower right inlet of the interstage heat exchanger (16) through the second electronic expansion valve (21) to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant. The two refrigerants then exchange heat in the interstage heat exchanger (16). The medium-temperature, medium-pressure refrigerant that enters the upper left inlet of the interstage heat exchanger (16) enters the third electronic expansion valve (22) through the lower left outlet. Another path enters the medium-temperature and medium-pressure gaseous and liquid mixed refrigerant at the lower right inlet of the interstage heat exchanger (16) and enters the mixing chamber (17) through the upper right outlet. It mixes with the high-temperature and medium-pressure gaseous refrigerant discharged from the low-pressure compressor (13). The refrigerant after entering the third electronic expansion valve (22) is throttled from medium-temperature and medium-pressure refrigerant to low-temperature and low-pressure refrigerant. Then it enters the user heat exchange device (20) for heating. After absorbing heat, the refrigerant changes from low-temperature and low-pressure refrigerant to medium-temperature and low-pressure refrigerant and enters the left side of the low-pressure compressor (13).

[0037] Operating Mode 7: Combined Heating Mode of Direct Solar Supply, Coupled Injection, and CO2 Two-Stage Compression Cycle When solar radiation is strong and the solar collector (1) has sufficient heat, the high-temperature hot water storage tank (2) directly supplies heat, and the solar coupled jet and dual-stage pressure circulation operate simultaneously. The solar collector (1) absorbs heat into the high-temperature hot water storage tank (2) for heat storage, and then enters the gas cooler (15) through the first solenoid valve (12) to supply heat to the user. The high-temperature hot water storage tank (2) provides heat to the working fluid, which enters the steam generator (3) through the pipeline to provide heat to the CO2 working fluid of the solar coupled jet unit (A), making it into a high-temperature and high-pressure superheated state. After releasing heat, the working fluid returns to the high-temperature hot water storage tank (2) for heating. The high-temperature, high-pressure CO2 flowing out of the steam generator (3) enters the ejector chamber of the ejector (4), entrains the low-temperature, low-pressure working fluid from the auxiliary evaporator (7), mixes and is discharged to the condenser (5). The liquid working fluid is cooled and depressurized by the first electronic expansion valve (11), absorbs heat in the auxiliary evaporator (7), and returns to the ejector (4). The gaseous working fluid is returned to the steam generator (3) by the refrigerant pump (8) for the next cycle. The high-temperature, medium-pressure, superheated gaseous refrigerant from the outlet of the low-pressure compressor (13) enters the mixing chamber. The refrigerant, which is a mixture of medium-temperature, medium-pressure gaseous and liquid refrigerant, enters the mixing chamber (17) through the left inlet and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber (17). The saturated gaseous refrigerant then flows out from the right outlet of the mixing chamber (17) and enters the second gas-liquid separator (18). From the second gas-liquid separator, the refrigerant flows to the high-pressure compressor (14). Under the action of the high-pressure compressor (14), the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. The high-temperature, high-pressure superheated gaseous refrigerant then enters the gas cooler (15) and is cooled by the gas cooler. The refrigerant in the heat exchanger (15) is cooled into a medium-temperature, high-pressure refrigerant by the hot water circulation loop. After cooling, the medium-temperature, high-pressure refrigerant enters the upper left inlet of the interstage heat exchanger (16) directly, and the other enters the lower right inlet of the interstage heat exchanger (16) through the second electronic expansion valve (21) to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant. The two refrigerants then exchange heat in the interstage heat exchanger (16). The medium-temperature, medium-pressure refrigerant that enters the upper left inlet of the interstage heat exchanger (16) enters the third electronic expansion valve (22) through the lower left outlet. Another path enters the medium-temperature and medium-pressure gaseous and liquid mixed refrigerant at the lower right inlet of the interstage heat exchanger (16) and enters the mixing chamber (17) through the upper right outlet. It mixes with the high-temperature and medium-pressure gaseous refrigerant discharged from the low-pressure compressor (13). The refrigerant after entering the third electronic expansion valve (22) is throttled from medium-temperature and medium-pressure refrigerant to low-temperature and low-pressure refrigerant. Then it enters the user heat exchange device (20) for heating. After absorbing heat, the refrigerant changes from low-temperature and low-pressure refrigerant to medium-temperature and low-pressure refrigerant and enters the left side of the low-pressure compressor (13).

[0038] Operating Mode 8: Nighttime CO2 Dual-Stage Compression Cycle Heating Mode At night, the main circulation unit (B) is used for heating. The high-temperature, medium-pressure superheated gaseous refrigerant from the low-pressure compressor (13) enters the left inlet of the mixing chamber (17) and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber (17). The saturated gaseous refrigerant flows out from the right outlet of the mixing chamber (17) and enters the second gas-liquid separator (18). The second gas-liquid separator exits to the high-pressure compressor (14). Under the action of the high-pressure compressor (14), the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. The high-temperature, high-pressure superheated gaseous refrigerant enters the gas cooler (15) and is cooled into a medium-temperature, high-pressure refrigerant by the hot water circulation loop in the gas cooler (15). The cooled medium-temperature, high-pressure refrigerant directly enters the upper left inlet of the interstage heat exchanger (16) and passes through the second electric... The sub-expansion valve (21) throttles the refrigerant into a low-temperature, medium-pressure gaseous and liquid mixture, which then enters the lower right inlet of the interstage heat exchanger (16). The two refrigerants then exchange heat in the interstage heat exchanger (16). The medium-temperature, medium-pressure refrigerant that enters the upper left inlet of the interstage heat exchanger (16) enters the third electronic expansion valve (22) through the lower left outlet. The other medium-temperature, medium-pressure gaseous and liquid mixture that enters the lower right inlet of the interstage heat exchanger (16) enters the mixing chamber (17) through the upper right outlet, where it mixes with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor (13). The refrigerant that enters the third electronic expansion valve (22) is throttled from a medium-temperature, medium-pressure refrigerant to a low-temperature, low-pressure refrigerant, and then enters the user heat exchange device (20) for heating. After absorbing heat, the refrigerant changes from a low-temperature, low-pressure refrigerant to a medium-temperature, low-pressure refrigerant and enters the left side of the low-pressure compressor (13).

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art without creative effort within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A solar-coupled jet-main-cycle system, characterized in that, It includes a solar-coupled jet unit, a main circulation unit, and a water supply unit, wherein: The solar coupled jet unit includes a solar thermal panel, which is connected to a high-temperature hot water storage tank. The high-temperature hot water storage tank is connected to a steam generator. The steam generator is connected to a condenser through an ejector. One end of the condenser is connected to an intermediate heat exchanger, which connects the steam generator and an auxiliary evaporator. The main circulation unit includes a low-pressure compressor, a high-pressure compressor, a gas cooler, an interstage heat exchanger, and a mixing chamber. One end of the mixing chamber is connected to the high-pressure compressor through a second gas-liquid separator. The high-pressure compressor is connected to the gas cooler. The gas cooler is also connected to the auxiliary evaporator. The interstage heat exchanger is connected to the low-pressure compressor through a user heat exchange device and a first gas-liquid separator. The water supply unit includes a medium-temperature hot water storage tank and a plate heat exchanger. One end of the medium-temperature hot water storage tank is connected to a condenser, and the other end is connected to a high-temperature hot water storage tank and a plate heat exchanger via pipelines. The plate heat exchanger is connected to the low-pressure compressor and the other end of the mixing chamber. An expansion valve or solenoid valve is installed on the connecting pipeline; When the solar radiation intensity is greater than the set value, the solar collector panel has sufficient heat and enters the direct solar heating mode. When the solar radiation intensity is less than the set value, the heat stored in the high-temperature hot water storage tank provides heat to the steam generator, which in turn provides heat to the carbon dioxide working fluid of the solar thermal injection unit, thus entering the solar coupled injection heating mode. When the solar radiation intensity is less than the set value and the heat source stored in the high-temperature hot water storage tank has been exhausted, the main circulation unit provides heat and enters the CO2 two-stage compression cycle heating mode. Depending on the solar radiation intensity and scenario requirements, the solar direct heating mode, the solar coupled jet heating mode, and / or the CO2 two-stage compression cycle heating mode are coupled to enter a joint working mode, so as to ensure that the best working conditions are achieved in the variable environment and obtain the maximum heat output with the minimum energy consumption.

2. The solar-coupled jet-main-cycle system as described in claim 1, characterized in that, A first water pump is installed on the connecting pipe between the solar thermal panel and the high-temperature hot water storage tank; a second water pump is installed on the connecting pipe between the high-temperature hot water storage tank and the steam generator; a first electronic expansion valve is installed between the intermediate heat exchanger and the auxiliary evaporator; a first solenoid valve is installed on the connecting pipe between the high-temperature hot water storage tank and the gas cooler; and a refrigerant pump is connected between the steam generator and the intermediate heat exchanger. One end of the interstage heat exchanger is connected to a second electronic expansion valve, and the other end of the interstage heat exchanger is connected to the user heat exchange device. A third electronic expansion valve is installed on the connecting pipe. A second solenoid valve and a third solenoid valve are installed on the connecting pipe between the interstage heat exchanger and the intermediate heat exchanger. A fifth solenoid valve is installed on the connecting pipe between the medium-temperature hot water storage tank and the high-temperature hot water storage tank, a sixth solenoid valve is installed on the connecting pipe between the medium-temperature hot water storage tank and the plate heat exchanger, and a third water pump is installed between the condenser and the medium-temperature hot water storage tank.

3. A control method based on the system described in claim 1 or 2, characterized in that, Includes the following steps: When the solar radiation intensity is greater than the set value, the solar collector panel has sufficient heat and enters the direct solar heating mode. When the solar radiation intensity is less than the set value, the heat stored in the high-temperature hot water storage tank provides heat to the steam generator, which in turn provides heat to the carbon dioxide working fluid of the solar thermal injection unit, thus entering the solar coupled injection heating mode. When the solar radiation intensity is less than the set value and the heat source stored in the high-temperature hot water storage tank has been exhausted, the main circulation unit provides heat and enters the CO2 two-stage compression cycle heating mode. Depending on the solar radiation intensity and scenario requirements, the solar direct heating mode, the solar coupled jet heating mode, and / or the CO2 two-stage compression cycle heating mode are coupled to enter a joint working mode, so as to ensure that the best working conditions are achieved in the variable environment and obtain the maximum heat output with the minimum energy consumption.

4. The control method as described in claim 1, characterized in that, The process of entering the solar coupled jet heating mode includes: when the solar radiation intensity is greater than the set value, resulting in sufficient heat from the solar collector, the high-temperature hot water storage tank directly supplies heat, the first solenoid valve opens, the other solenoid valves close, the solar collector absorbs heat into the high-temperature storage tank for heat storage, and then passes through the first solenoid valve into the gas cooler to supply heat to the user.

5. The control method as described in claim 1, characterized in that, The process of entering the solar coupled jet heating mode includes: when solar radiation is less than the set value, resulting in insufficient heat from the solar collector, solar coupled jet heating is used. When the high-temperature hot water storage tank stores heat to provide heat to the steam generator, the first electronic expansion valve opens, while the other electronic expansion valves and solenoid valves close. The high-temperature hot water storage tank provides heat to the working fluid, which enters the steam generator through pipelines to provide heat to the CO2 working fluid of the solar thermal jet unit, making it into a high-temperature and high-pressure superheated state. After releasing heat, the working fluid returns to the high-temperature hot water storage tank for reheating. The high-temperature and high-pressure CO2 flowing out of the steam generator enters the jet chamber of the ejector, entrains the low-temperature and low-pressure working fluid from the auxiliary evaporator, mixes, and discharges to the condenser. The liquid working fluid is cooled and depressurized by the first electronic expansion valve, absorbs heat in the auxiliary evaporator, and returns to the ejector. The gaseous working fluid returns to the steam generator via the refrigerant pump.

6. The control method as described in claim 1, characterized in that, The process of entering the CO2 two-stage compression cycle heating mode includes: when solar radiation is less than the set value, the solar collectors cannot provide heat at all, and the heat source stored in the high-temperature hot water storage tank is exhausted, the high-temperature medium-pressure superheated gaseous refrigerant from the low-pressure compressor outlet enters one end of the mixing chamber and mixes with the medium-temperature medium-pressure gaseous and liquid refrigerant entering the upper end of the mixing chamber. The saturated gaseous refrigerant then flows out from the other end of the mixing chamber and enters the second gas-liquid separator. From the second gas-liquid separator, it reaches the high-pressure compressor. Under the action of the high-pressure compressor, the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. The high-temperature, high-pressure superheated gaseous refrigerant enters the gas cooler, where it is cooled by the hot water circulation loop to become a medium-temperature, high-pressure refrigerant. The cooled medium-temperature, high-pressure refrigerant then flows through... The refrigerant enters directly from the upper inlet on one side of the interstage heat exchanger. One path is throttled by the second electronic expansion valve to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant, which then enters the lower inlet on one side of the interstage heat exchanger. The two refrigerants then exchange heat in the interstage heat exchanger. The medium-temperature, medium-pressure refrigerant entering from the upper inlet on one side of the interstage heat exchanger enters the third electronic expansion valve through the lower outlet on one side. The other path, a medium-temperature, medium-pressure gaseous and liquid mixed refrigerant entering from the lower inlet on the other side of the interstage heat exchanger, enters the mixing chamber through the upper right outlet, where it mixes with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor. The refrigerant entering the third electronic expansion valve is throttled from medium-temperature, medium-pressure to low-temperature, low-pressure, and then enters the user's heat exchange device for heating. After absorbing heat, the refrigerant changes from low-temperature, low-pressure to medium-temperature, low-pressure and enters the low-pressure compressor side.

7. The control method as described in claim 1, characterized in that, The process of entering the solar direct heating combined with solar coupled jet heating mode includes: when the solar radiation is greater than the set value, resulting in sufficient heat from the solar collector, the high-temperature hot water storage tank direct heating and solar coupled jet heating operate simultaneously. The solar collector absorbs heat into the high-temperature storage tank for heat storage and then enters the gas cooler through the first solenoid valve to provide heat to the user. When the high-temperature hot water storage tank stores heat to provide heat to the steam generator, it also provides heat to the working fluid. This heat is then introduced into the steam generator through pipelines to provide heat to the CO2 working fluid, causing it to become a superheated state under high temperature and pressure. After releasing heat, the working fluid returns to the high-temperature hot water storage tank for reheating.

8. The control method as described in claim 1, characterized in that, The process of entering the solar direct heating combined with CO2 two-stage compression cycle heating mode includes: When solar radiation is strong, resulting in sufficient heat from the solar collectors, the system operates simultaneously with direct heating from a high-temperature hot water storage tank and a dual-pressure circulation system. Heat is absorbed by the solar collectors and stored in the high-temperature storage tank before passing through a first solenoid valve and entering a gas cooler to supply heat to users. High-temperature, medium-pressure superheated gaseous refrigerant from the low-pressure compressor outlet enters one inlet of the mixing chamber and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber. Saturated gaseous refrigerant flows out from the other end of the mixing chamber and enters the second gas-liquid separator. From the second gas-liquid separator, it reaches the high-pressure compressor, where it transforms from a medium-pressure saturated gaseous refrigerant into a high-temperature, high-pressure superheated gaseous refrigerant. This high-temperature, high-pressure superheated gaseous refrigerant then enters the gas cooler, where it is cooled by the hot water circulation loop to become a medium-temperature, high-pressure refrigerant. After cooling, the medium-temperature, high-pressure refrigerant enters directly into the upper inlet of one side of the interstage heat exchanger, while the other path is throttled by the second electronic expansion valve to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant, which then enters the lower inlet of the other side of the interstage heat exchanger. The two refrigerants then exchange heat in the interstage heat exchanger. The medium-temperature, medium-pressure refrigerant entering the upper inlet of one side of the interstage heat exchanger enters the third electronic expansion valve through the lower left outlet, while the other medium-temperature, medium-pressure gaseous and liquid mixed refrigerant entering the lower inlet of one side of the interstage heat exchanger enters the mixing chamber through the upper right outlet, mixing with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor. The refrigerant entering the third electronic expansion valve is throttled from medium-temperature, medium-pressure to low-temperature, low-pressure, and then enters the user's heat exchange device for heating. After absorbing heat, the refrigerant changes from low-temperature, low-pressure to medium-temperature, low-pressure and enters the low-pressure compressor.

9. The control method as described in claim 1, characterized in that, The process of entering the solar coupled jet combined with CO2 two-stage compression cycle heating mode includes: when the solar radiation is less than the set value, causing the solar collector to be unable to provide heat at all, and the heat source stored in the high-temperature hot water storage tank is exhausted, solar coupled jet and two-stage compression cycle are used for heating. When the heat stored in the high-temperature hot water storage tank provides heat to the steam generator, the high-temperature hot water storage tank provides heat to the working fluid, which enters the steam generator through the pipeline to provide heat to the CO2 working fluid, making it into a high-temperature and high-pressure superheated state. After releasing heat, the working fluid returns to the high-temperature hot water storage tank for reheating. High-temperature, high-pressure CO2 flowing from the steam generator enters the ejector chamber of the ejector, entraining the low-temperature, low-pressure working fluid from the auxiliary evaporator. The mixture is then discharged to the condenser. The liquid working fluid, after being cooled and depressurized by the first electronic expansion valve, absorbs heat in the auxiliary evaporator and returns to the ejector. The gaseous working fluid returns to the steam generator via the refrigerant pump for the next cycle. High-temperature, medium-pressure superheated gaseous refrigerant from the low-pressure compressor outlet enters the left inlet of the mixing chamber and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber. The saturated gaseous refrigerant then flows out from one end of the mixing chamber and enters the second gas-liquid separator. From the second gas-liquid separator, it reaches the high-pressure compressor. Under the action of the high-pressure compressor, the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. This high-temperature, high-pressure superheated gaseous refrigerant enters the gas cooler, where it is heated. The water circulation loop cools the medium-temperature, high-pressure refrigerant. The cooled medium-temperature, high-pressure refrigerant enters directly into the upper inlet of one side of the interstage heat exchanger, while the other path is throttled by the second electronic expansion valve to become a low-temperature, medium-pressure gaseous and liquid mixed refrigerant, which then enters the lower inlet of the other side of the interstage heat exchanger. The two refrigerants then exchange heat in the interstage heat exchanger. The medium-temperature, medium-pressure refrigerant entering the upper inlet of one side of the interstage heat exchanger enters the third electronic expansion valve through the lower left outlet. The other path, the medium-temperature, medium-pressure gaseous and liquid mixed refrigerant entering the lower inlet of the other side of the interstage heat exchanger, enters the mixing chamber through the upper right outlet, mixing with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor. The refrigerant entering the third electronic expansion valve is throttled from medium-temperature, medium-pressure to low-temperature, low-pressure, and then enters the user's heat exchange device for heating. After absorbing heat, the refrigerant changes from low-temperature, low-pressure to medium-temperature, low-pressure and enters the low-pressure compressor.

10. The control method as described in claim 1, characterized in that, The process of entering the combined heating mode of direct solar power supply, coupled injection and CO2 two-stage compression cycle includes: the solar collector absorbs heat into the high-temperature heat storage box for heat storage, and then enters the gas cooler through the first solenoid valve to provide heat to the user. The high-temperature hot water storage tank provides heat to the working fluid, which enters the steam generator through pipelines to provide heat to the CO2 working fluid, making it into a superheated state with high temperature and high pressure. After releasing heat, the working fluid returns to the high-temperature hot water storage tank for reheating. The high-temperature, high-pressure CO2 flowing out of the steam generator enters the ejector chamber, entrains the low-temperature, low-pressure working fluid from the auxiliary evaporator, mixes and is discharged to the condenser. The liquid working fluid is cooled and depressurized by the first electronic expansion valve, absorbs heat in the auxiliary evaporator, and returns to the ejector. The gaseous working fluid is returned to the steam generator by the fluorine pump for the next cycle. The high-temperature, medium-pressure superheated gaseous refrigerant exiting the low-pressure compressor enters one inlet of the mixing chamber and mixes with the medium-temperature, medium-pressure gaseous and liquid refrigerant entering the upper inlet of the mixing chamber. The saturated gaseous refrigerant then flows out from one outlet of the mixing chamber and enters the second gas-liquid separator. From the second gas-liquid separator, it reaches the high-pressure compressor. Under the action of the high-pressure compressor, the refrigerant changes from a medium-pressure saturated gaseous refrigerant to a high-temperature, high-pressure superheated gaseous refrigerant. This high-temperature, high-pressure superheated gaseous refrigerant enters the gas cooler, where it is cooled by the hot water circulation loop to become a medium-temperature, high-pressure refrigerant. The cooled medium-temperature, high-pressure refrigerant then enters either directly at the upper inlet of one side of the interstage heat exchanger or is throttled by the second electronic expansion valve to become... The low-temperature, medium-pressure gaseous and liquid refrigerant mixture then enters the other lower inlet of the interstage heat exchanger. The two refrigerants then exchange heat in the interstage heat exchanger. The medium-temperature, medium-pressure refrigerant entering the upper inlet on one side of the interstage heat exchanger enters the third electronic expansion valve through the lower left outlet. The other medium-temperature, medium-pressure gaseous and liquid refrigerant entering the other lower inlet of the interstage heat exchanger enters the mixing chamber through the upper right outlet, mixing with the high-temperature, medium-pressure gaseous refrigerant discharged from the low-pressure compressor. The refrigerant entering the third electronic expansion valve is throttled from medium-temperature, medium-pressure to low-temperature, low-pressure, and then enters the user's heat exchange device for heating. After absorbing heat, the refrigerant changes from low-temperature, low-pressure to medium-temperature, low-pressure and enters the low-pressure compressor.

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