A solar-powered heating and cooling system and its control method

Abstract

The present invention relates to the field of combining solar thermal technology with buildings, and provides a composite heating and cooling system utilizing solar energy and a control method thereof. During the heating season, during the day, the system operates in a gravity heat pipe or power heat pipe mode, utilizing solar energy to heat the room. At night, the system switches to an air source heat pump operation mode, which does not require a heat storage device and can still meet the indoor heating needs. During the cooling season, a four-way reversing valve is used to switch to a vapor compression refrigeration mode, and the room is cooled through the second indoor heat exchanger. During the transition season, the system operates in a gravity heat pipe mode with no operating energy consumption. The refrigerant absorbs solar radiation heat in the first outdoor heat exchanger and transfers the heat to a hot water tank to provide free domestic hot water indoors. The present invention meets the heating, cooling, and domestic hot water needs of buildings in different seasons. The system switches to different operating modes through valve adjustment, making full use of solar heat to reduce building energy consumption.

Description

Technical Field

[0001] The present invention relates to the field of combining solar thermal technology with architecture, and in particular to a composite heating and cooling system utilizing solar energy and a control method thereof. Background Art

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

[0003] With increasing energy demand and increasingly prominent environmental issues, solar energy as a clean, renewable energy source has attracted considerable attention. Solar thermal systems combine multiple functions, such as heating and domestic hot water production. When combined with buildings, they can effectively reduce building energy consumption while meeting some energy needs. However, the temporal discontinuity of solar energy resources presents difficulties in practical application. Solar thermal systems often require large-capacity heat storage devices and auxiliary heat sources. With increasing demands for indoor space, current energy utilization rates are low, and the system cannot autonomously switch between indoor and outdoor conditions, resulting in high building energy consumption. Summary of the Invention

[0004] In order to address the deficiencies of the prior art, the present invention provides a composite heating and cooling system utilizing solar energy and a control method thereof, which can improve energy utilization efficiency and system adaptability, can switch between different operating modes according to different outdoor conditions, and achieve reduction in building energy consumption through reasonable and effective operation control methods.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A first aspect of the present invention provides a combined heating and cooling system utilizing solar energy.

[0007] A solar-powered heating and cooling system includes a control module, an outdoor pipeline, an indoor pipeline, a compression pipeline, and a regulating pipeline, all connected to the control module; the outdoor pipeline is connected to one end of the regulating pipeline, the other end of the regulating pipeline is connected to the indoor pipeline, and both ends of the indoor pipeline, the outdoor pipeline, and the compression pipeline are connected to a reversing valve;

[0008] The outdoor pipeline includes a first outdoor pipeline and a second outdoor pipeline connected in parallel, the first outdoor pipeline includes a first outdoor side heat exchanger and a first control valve connected in series, and the second outdoor pipeline includes a second outdoor side heat exchanger and a second control valve connected in series;

[0009] The regulating pipeline includes an expansion valve and a fluorine pump connected in series, the expansion valve is connected in parallel with the third control valve, and the inlet of the fluorine pump is connected to the fourth control valve and then in parallel with the fifth control valve;

[0010] The indoor pipeline includes a first indoor pipeline and a second indoor pipeline connected in parallel, the second indoor side heat exchanger is connected in series with the sixth control valve, and the inlet of the first indoor side heat exchanger is connected to the seventh control valve;

[0011] The compression pipeline includes a compressor, the inlet of the compressor is connected to the eighth control valve and then connected in parallel with the ninth control valve;

[0012] The control module is used to obtain the season type, select the operation mode of the heating and cooling composite system according to the season type, and selectively open or close the pipeline where the control valve is located according to the operation mode.

[0013] Furthermore, a first temperature sensor is provided at the tube wall of the first outdoor heat exchanger for obtaining the tube wall temperature of the first outdoor heat exchanger; a second temperature sensor is provided at the refrigerant inlet of the first outdoor heat exchanger for obtaining the refrigerant inlet temperature of the first outdoor heat exchanger; a third temperature sensor is provided at the refrigerant outlet of the first outdoor heat exchanger for obtaining the refrigerant outlet temperature of the first outdoor heat exchanger; a fourth temperature sensor is provided on the surface of the second indoor heat exchanger for obtaining the surface temperature of the second indoor heat exchanger.

[0014] Furthermore, the control module is also used to obtain the tube wall temperature of the first outdoor heat exchanger, the surface temperature of the second indoor heat exchanger, the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger during the heating season; obtain the heat pipe driving temperature difference according to the difference between the tube wall temperature of the first outdoor heat exchanger and the surface temperature of the second indoor heat exchanger; obtain the refrigerant inlet and outlet temperature difference according to the difference between the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger; determine the operation mode of the heating and cooling composite system according to the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference, and selectively open or close the pipeline where the control valve is located.

[0015] Furthermore, the control module is further configured to, in response to the heat pipe driving temperature difference being less than a first set value, control the system in an air source heat pump mode, and control the second control valve, the fifth control valve, the sixth control valve, and the eighth control valve to be open, and the first control valve, the third control valve, the fourth control valve, the seventh control valve, and the ninth control valve to be closed, so that the compressor and the expansion valve are started, and the fluorine pump is turned off;

[0016] Furthermore, the control module is further configured to, in response to the heat pipe driving temperature difference being greater than or equal to a first set value and the refrigerant inlet and outlet temperature difference being less than or equal to a second set value, control the system in a gravity-type heat pipe operation mode, and control the first control valve, the third control valve, the fifth control valve, the sixth control valve, and the ninth control valve to be open, and the second control valve, the fourth control valve, the seventh control valve, and the eighth control valve to be closed, so that the compressor, the expansion valve, and the fluorine pump are all turned off;

[0017] Furthermore, the control module is also used to control the first control valve, the third control valve, the fourth control valve, the sixth control valve and the ninth control valve to open, and the second control valve, the fifth control valve, the seventh control valve and the eighth control valve to close in response to the heat pipe driving temperature difference being greater than or equal to the first set value and the refrigerant inlet and outlet temperature difference being greater than the second set value, so that the fluorine pump is started and the compressor and the expansion valve are closed in the power type heat pipe operation mode.

[0018] Furthermore, the control module is also used to control the system in vapor compression refrigeration mode during the cooling season, and control the second control valve, the fifth control valve, the sixth control valve and the eighth control valve to open, and the first control valve, the third control valve, the fourth control valve, the seventh control valve and the ninth control valve to close, so that the compressor and the expansion valve are started and the fluorine pump is turned off.

[0019] Furthermore, the control module is also used to control the system in gravity heat pipe mode during the transition season, and control the first control valve, the third control valve, the fifth control valve, the seventh control valve and the ninth control valve to open, and the second control valve, the fourth control valve, the sixth control valve and the eighth control valve to close, so that the compressor, the expansion valve and the fluorine pump are all turned off.

[0020] A second aspect of the present invention provides a control method for a combined heating and cooling system utilizing solar energy.

[0021] A control method for a combined heating and cooling system utilizing solar energy, using the combined heating and cooling system utilizing solar energy according to the first aspect, comprises:

[0022] Get the season type;

[0023] Select the operation mode of the heating and cooling system according to the season type;

[0024] Depending on the operating mode, the pipeline where the control valve is located is selectively opened or closed.

[0025] Furthermore, the process of selecting the operating mode of the heating and cooling composite system according to the season type includes: in the heating season, obtaining the tube wall temperature of the first outdoor heat exchanger, the surface temperature of the second indoor heat exchanger, the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger; obtaining the heat pipe driving temperature difference according to the difference between the tube wall temperature of the first outdoor heat exchanger and the surface temperature of the second indoor heat exchanger; obtaining the refrigerant inlet and outlet temperature difference according to the difference between the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger; and determining the operating mode of the heating and cooling composite system according to the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference.

[0026] Furthermore, the process of determining the operating mode of the heating and cooling composite system based on the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is less than a first set value, selecting the air source heat pump mode, the second outdoor heat exchanger acts as an evaporator to absorb heat from the air, the working fluid is vaporized and enters the compressor through the refrigerant pipe, the working fluid temperature and pressure increase in the compressor, enters the second indoor heat exchanger, releases heat to the room, condenses into a liquid, is throttled by the expansion valve to a low temperature and low pressure state, and then returns to the second outdoor heat exchanger;

[0027] Furthermore, the process of determining the operating mode of the heating and cooling composite system based on the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is greater than or equal to a first set value, and the refrigerant inlet and outlet temperature difference is less than or equal to a second set value, selecting the gravity-type heat pipe operating mode, the first outdoor heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes a gas, the density decreases, and enters the second indoor heat exchanger along the refrigerant pipe under the action of buoyancy, after exchanging heat with the indoor cold air, part or all of the working fluid becomes a liquid, the density increases, and returns to the first outdoor heat exchanger along the refrigerant pipe under the action of gravity;

[0028] Furthermore, the process of determining the operating mode of the heating and cooling composite system based on the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is greater than or equal to the first set value, and the refrigerant inlet and outlet temperature difference is greater than the second set value, the dynamic heat pipe operation mode is selected, the first outdoor heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes gas and enters the second indoor heat exchanger through the refrigerant pipe, becomes liquid after exchanging heat with the indoor cold air, and returns to the first outdoor heat exchanger along the refrigerant pipe driven by the fluorine pump.

[0029] Furthermore, the process of selecting the operating mode of the combined heating and cooling system according to the seasonal type further includes: in the cooling season, selecting the vapor compression cooling mode, wherein the second indoor heat exchanger acts as an evaporator to absorb heat from the indoor air, and the working fluid is vaporized and enters the compressor, where the temperature and pressure of the working fluid increase, and then enters the second outdoor heat exchanger, where it releases heat to the outdoor air and condenses into a liquid state, and then passes through the expansion valve for throttling and pressure reduction, and then returns to the second indoor heat exchanger;

[0030] Furthermore, the process of selecting the operating mode of the heating and cooling composite system according to the seasonal type also includes: in the transition season, selecting the gravity heat pipe mode, the first outdoor heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes gas, the density decreases, and enters the first indoor heat exchanger along the refrigerant pipe under the action of buoyancy. After exchanging heat with tap water, part or all of the working fluid becomes liquid, the density increases, and returns to the first outdoor heat exchanger along the refrigerant pipe under the action of gravity.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The present invention combines solar thermal technology with a multi-mode switching heating and cooling composite system, making full use of solar energy for free heating during the day and switching to air source heat pump heating at night without the need for a heat storage device.

[0033] 2. The present invention improves the system's adaptability to the building's heating and cooling needs under different outdoor conditions by adjusting the operating mode of the valve switching system, achieving multi-functional output in a simple system form, and meeting the needs of heating, cooling, and domestic hot water supply in buildings in different seasons.

[0034] 3. The present invention uses Freon as a refrigerant to transport heat. Compared with the water refrigerant in traditional solar thermal systems, on the one hand, it solves the problem of water pipe freezing in northern winter; on the other hand, due to phase change heat transfer, the required refrigerant flow rate is lower and the heat exchange efficiency is higher, which not only saves pump consumption, but also saves the heat exchange area of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0036] Figure 1 This is a structural diagram of a composite heating and cooling system utilizing solar energy;

[0037] In the figure: 1. Solar collector; 2. First outdoor heat exchanger; 3. Second outdoor heat exchanger; 4. Compressor; 5. Four-way reversing valve; 6. First indoor heat exchanger; 7. Second indoor heat exchanger; 8. Expansion valve; 9. Fluorine pump; 10. Hot water tank; 11-1. First temperature sensor; 11-2. Second temperature sensor; 11-3. Third temperature sensor; 11-4. Fourth temperature sensor; 12-1. First control valve; 12-2. Second control valve; 12-3. Third control valve; 12-4. Fourth control valve; 12-5. Fifth control valve; 12-6. Sixth control valve; 12-7. Seventh control valve; 12-8. Eighth control valve; 12-9. Ninth control valve. DETAILED DESCRIPTION

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0039] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0040] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0041] In the present invention, terms such as "connected" and "connection" should be interpreted broadly to mean a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediary. Relevant researchers or technicians in this field may determine the specific meanings of these terms in the present invention based on specific circumstances, and they should not be construed as limitations on the present invention.

[0042] In the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0043] Example 1

[0044] like Figure 1 As shown, a combined heating and cooling system utilizing solar energy includes: a first outdoor heat exchanger 2 and a second outdoor heat exchanger 3 are connected in parallel and connected to a four-way reversing valve 5 through a refrigerant pipe, and the inlet and outlet of a compressor 4 are both connected to the four-way reversing valve 5 through a refrigerant pipe; a first indoor heat exchanger 6 and a second indoor heat exchanger 7 are connected in parallel and connected to the four-way reversing valve 5 through a refrigerant pipe.

[0045] Specifically, the first outdoor heat exchanger 2 is connected in series with the first control valve 12-1; the second outdoor heat exchanger 3 is connected in series with the second control valve 12-2; the expansion valve 8 is connected in parallel with the third control valve 12-3; the inlet of the fluorine pump 9 is connected to the fourth control valve 12-4 and in parallel with the fifth control valve 12-5; the second indoor heat exchanger 7 is connected in series with the sixth control valve 12-6; the inlet of the first indoor heat exchanger 6 is connected to the seventh control valve 12-7; the inlet of the compressor 4 is connected to the eighth control valve 12-8 and in parallel with the ninth control valve 12-9.

[0046] More specifically, the first outdoor heat exchanger 2 is combined with the solar collector 1 to directly absorb solar energy to obtain heat; the first indoor heat exchanger 6 is placed in the hot water tank 10 to heat water.

[0047] The second outdoor heat exchanger 3 is a fin-tube heat exchanger, and the second indoor heat exchanger 7 is a ceiling radiation panel.

[0048] The refrigerant pipes use Freon such as R134a and R410A.

[0049] The temperature sensors are located on the tube wall of the first outdoor heat exchanger 2, the refrigerant inlet and outlet of the first outdoor heat exchanger 2, and the surface of the second indoor heat exchanger 7. Specifically:

[0050] The first temperature sensor 11 - 1 is located on the tube wall 2 of the first outdoor heat exchanger, and obtains the tube wall temperature T1 of the first outdoor heat exchanger 2;

[0051] The second temperature sensor 11-2 is located at the refrigerant inlet of the first outdoor heat exchanger 2, and obtains the refrigerant inlet temperature T2 of the first outdoor heat exchanger 2;

[0052] The third temperature sensor 11-3 is located at the refrigerant outlet of the first outdoor heat exchanger 2, and obtains the refrigerant outlet temperature T3 of the first outdoor heat exchanger 2;

[0053] The fourth temperature sensor 11 - 4 is located on the surface of the second indoor heat exchanger 7 and obtains the surface temperature T4 of the second indoor heat exchanger 7 .

[0054] According to the heat pipe driving temperature difference ΔT1 = (T1-T4) and the refrigerant inlet and outlet temperature difference ΔT2 = (T3-T2) of the first outdoor heat exchanger 2, the system is switched to different operating modes by adjusting the control valve, specifically:

[0055] (1) Heating season

[0056] When the heat pipe driving temperature difference ΔT1 is less than the first set value, the separate heat pipe cannot start normally, and the system operates in the air source heat pump mode. At this time, the compressor 4 and the expansion valve 8 are connected in series to the loop, and the fluorine pump 9 is bypassed. Specifically:

[0057] When ΔT1 is less than the first set value, the system operates in air source heat pump mode, the second control valve 12-2, the fifth control valve 12-5, the sixth control valve 12-6 and the eighth control valve 12-8 are opened, the first control valve 12-1, the third control valve 12-3, the fourth control valve 12-4, the seventh control valve 12-7 and the ninth control valve 12-9 are closed, the compressor 4 and the expansion valve 8 are started, and the fluorine pump 9 is turned off.

[0058] When the heat pipe driving temperature difference ΔT1 is greater than or equal to the first set value and the refrigerant inlet and outlet temperature difference ΔT2 of the first outdoor heat exchanger 2 is less than or equal to the second set value, the system switches to the gravity heat pipe operation mode. At this time, the compressor 4, expansion valve 8 and fluorine pump 9 in the loop are bypassed. Specifically:

[0059] When ΔT1 is greater than or equal to the first set value and ΔT2 is less than or equal to the second set value, the system operates in gravity heat pipe mode, the first control valve 12-1, the third control valve 12-3, the fifth control valve 12-5, the sixth control valve 12-6 and the ninth control valve 12-9 are opened, the second control valve 12-2, the fourth control valve 12-4, the seventh control valve 12-7 and the eighth control valve 12-8 are closed, and the compressor 4, the expansion valve 8 and the fluorine pump 9 are all closed.

[0060] When the heat pipe driving temperature difference ΔT1 is greater than or equal to the first set value and the refrigerant inlet and outlet temperature difference ΔT2 of the first outdoor heat exchanger 2 is greater than the second set value, the system switches to the dynamic heat pipe operation mode. At this time, the fluorine pump 9 is connected in series to the loop, and the compressor 4 and the expansion valve 8 are bypassed. Specifically:

[0061] When ΔT1 is greater than or equal to the first set value and ΔT2 is greater than the second set value, the system operates in the dynamic heat pipe mode, the first control valve 12-1, the third control valve 12-3, the fourth control valve 12-4, the sixth control valve 12-6 and the ninth control valve 12-9 are opened, the second control valve 12-2, the fifth control valve 12-5, the seventh control valve 12-7 and the eighth control valve 12-8 are closed, the fluorine pump 9 is started, and the compressor 4 and the expansion valve 8 are closed.

[0062] (2) Cooling season

[0063] Rotate the four-way reversing valve 5, the system operates in vapor compression refrigeration mode, the second control valve 12-2, the fifth control valve 12-5, the sixth control valve 12-6 and the eighth control valve 12-8 are opened, the first control valve 12-1, the third control valve 12-3, the fourth control valve 12-4, the seventh control valve 12-7 and the ninth control valve 12-9 are closed, the compressor 4 and the expansion valve 8 are started, and the fluorine pump 9 is turned off.

[0064] (3) Transition Season

[0065] The system operates in gravity heat pipe mode, the first control valve 12-1, the third control valve 12-3, the fifth control valve 12-5, the seventh control valve 12-7 and the ninth control valve 12-9 are open, the second control valve 12-2, the fourth control valve 12-4, the sixth control valve 12-6 and the eighth control valve 12-8 are closed, and the compressor 4, the expansion valve 8 and the fluorine pump 9 are all closed.

[0066] Air source heat pump mode: The second outdoor heat exchanger 3 acts as an evaporator to absorb heat from the air. After the working fluid is vaporized, it enters the compressor 4 through the refrigerant pipe. The temperature and pressure of the working fluid increase in the compressor 4, and then enters the second indoor heat exchanger 7. After releasing heat to the room, it condenses into liquid. Then, it is throttled by the expansion valve to become a low-temperature and low-pressure state, and then returns to the second outdoor heat exchanger 3.

[0067] Vapor compression refrigeration mode: The second indoor heat exchanger 7 acts as an evaporator to absorb heat from the indoor air. The working fluid is vaporized and enters the compressor 4. The working fluid temperature and pressure increase in the compressor 4, and then enters the second outdoor heat exchanger 3. After releasing heat to the outdoor air, it condenses into liquid. It then passes through the expansion valve for throttling and pressure reduction, and then returns to the second indoor heat exchanger 7.

[0068] Gravity-type heat pipe mode: The first outdoor heat exchanger 2 acts as an evaporator to absorb heat from the solar collector 1. The working fluid absorbs heat and undergoes a phase change. Part or all of the working fluid becomes gas, and the density decreases. Under the action of buoyancy, it enters the second indoor heat exchanger 7 (heating season) or the first indoor heat exchanger 6 (transition season) along the refrigerant pipe. After exchanging heat with the indoor cold air (heating season) or tap water (transition season), part or all of the working fluid becomes liquid, and the density increases. Under the action of gravity, it returns to the first outdoor heat exchanger 2 along the refrigerant pipe.

[0069] Power type heat pipe mode: The first outdoor heat exchanger 2 acts as an evaporator to absorb heat from the solar collector 1. The working fluid absorbs heat and undergoes a phase change. Part or all of the working fluid becomes gas and enters the second indoor heat exchanger 7 through the refrigerant pipe. After exchanging heat with the indoor cold air, it becomes liquid and returns to the first outdoor heat exchanger 2 along the refrigerant pipe under the drive of the fluorine pump 9.

[0070] Example 2

[0071] Embodiment 2 of the present invention provides a control method for a combined heating and cooling system utilizing solar energy, and the combined heating and cooling system utilizing solar energy described in embodiment 1 includes:

[0072] Get the season type;

[0073] Select the operation mode of the heating and cooling system according to the season type;

[0074] Depending on the operating mode, the pipeline where the control valve is located is selectively opened or closed.

[0075] As one or more implementation methods, the process of selecting the operating mode of the heating and cooling composite system according to the season type includes: in the heating season, obtaining the tube wall temperature of the first outdoor heat exchanger, the surface temperature of the second indoor heat exchanger, the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger; obtaining the heat pipe driving temperature difference according to the difference between the tube wall temperature of the first outdoor heat exchanger and the surface temperature of the second indoor heat exchanger; obtaining the refrigerant inlet and outlet temperature difference according to the difference between the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger; and determining the operating mode of the heating and cooling composite system according to the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference.

[0076] As one or more embodiments, the process of determining the operating mode of the combined heating and cooling system based on the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is less than a first set value, selecting the air source heat pump mode, the second outdoor heat exchanger acts as an evaporator to absorb heat from the air, the working fluid is vaporized and enters the compressor through the refrigerant pipe, the working fluid temperature and pressure increase in the compressor, enters the second indoor heat exchanger, releases heat to the room, and condenses into a liquid state, is throttled by the expansion valve to a low-temperature and low-pressure state, and then returns to the second outdoor heat exchanger;

[0077] As one or more implementation methods, the process of determining the operating mode of the heating and cooling composite system based on the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is greater than or equal to a first set value, and the refrigerant inlet and outlet temperature difference is less than or equal to a second set value, selecting the gravity-type heat pipe operation mode, the first outdoor heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes a gas, the density decreases, and enters the second indoor heat exchanger along the refrigerant pipe under the action of buoyancy. After exchanging heat with the indoor cold air, part or all of the working fluid becomes a liquid, the density increases, and returns to the first outdoor heat exchanger along the refrigerant pipe under the action of gravity;

[0078] As one or more implementation methods, the process of determining the operating mode of the heating and cooling composite system based on the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is greater than or equal to the first set value, and the refrigerant inlet and outlet temperature difference is greater than the second set value, the dynamic heat pipe operation mode is selected, the first outdoor heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes gas and enters the second indoor heat exchanger through the refrigerant pipe, becomes liquid after exchanging heat with the indoor cold air, and returns to the first outdoor heat exchanger along the refrigerant pipe driven by the fluorine pump.

[0079] In one or more embodiments, the process of selecting an operating mode of the combined heating and cooling system according to the seasonal type further includes: in the cooling season, selecting a vapor compression cooling mode, wherein the second indoor heat exchanger acts as an evaporator to absorb heat from the indoor air, and the working fluid vaporizes and enters the compressor, where the temperature and pressure of the working fluid increase, and then enters the second outdoor heat exchanger, where it releases heat to the outdoor air and condenses into a liquid state, and then passes through an expansion valve for throttling and pressure reduction, and then returns to the second indoor heat exchanger;

[0080] As one or more implementation methods, the process of selecting the operating mode of the heating and cooling composite system according to the season type also includes: in the transition season, selecting the gravity heat pipe mode, the first outdoor outside heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes gas, the density decreases, and enters the first indoor inside heat exchanger along the refrigerant pipe under the action of buoyancy. After exchanging heat with tap water, part or all of the working fluid becomes liquid, the density increases, and returns to the first outdoor outside heat exchanger along the refrigerant pipe under the action of gravity.

[0081] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A solar-powered heating and cooling system, characterized in that: include: A control module and an outdoor pipeline, an indoor pipeline, a compression pipeline and a regulating pipeline all connected to the control module, wherein the outdoor pipeline is connected to one end of the regulating pipeline, the other end of the regulating pipeline is connected to the indoor pipeline, and both ends of the indoor pipeline, the outdoor pipeline and the compression pipeline are connected to the reversing valve; The outdoor pipeline includes a first outdoor pipeline and a second outdoor pipeline connected in parallel, the first outdoor pipeline includes a first outdoor side heat exchanger and a first control valve connected in series, and the second outdoor pipeline includes a second outdoor side heat exchanger and a second control valve connected in series; The regulating pipeline includes an expansion valve and a fluorine pump connected in series, the expansion valve is connected in parallel with the third control valve, and the inlet of the fluorine pump is connected to the fourth control valve and then in parallel with the fifth control valve; The indoor pipeline includes a first indoor pipeline and a second indoor pipeline connected in parallel, the second indoor side heat exchanger is connected in series with the sixth control valve, and the inlet of the first indoor side heat exchanger is connected to the seventh control valve; The compression pipeline includes a compressor, the inlet of the compressor is connected to the eighth control valve and then connected in parallel with the ninth control valve; A control module is used to obtain the season type, select the operation mode of the heating and cooling composite system according to the season type, and selectively open or close the pipeline where the control valve is located according to the operation mode; The control module is also used to determine the operating mode of the heating and cooling composite system during the heating season based on the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference, and selectively open or close the pipeline where the control valve is located; the operating modes include air source heat pump mode, gravity heat pipe operation mode, and power heat pipe operation mode; The heat pipe driving temperature difference is the difference between the tube wall temperature of the first outdoor heat exchanger and the surface temperature of the second indoor heat exchanger; the refrigerant inlet and outlet temperature difference is the difference between the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger; the first outdoor heat exchanger is combined with a solar collector to directly absorb solar heat; The control module is also used to control the system in a vapor compression refrigeration mode during the cooling season; The control module is further configured to control the system in a gravity heat pipe mode during transition seasons.

2. The solar energy heating and cooling system according to claim 1, characterized in that: A first temperature sensor is provided at the tube wall of the first outdoor heat exchanger, for obtaining the tube wall temperature of the first outdoor heat exchanger; a second temperature sensor is provided at the refrigerant inlet of the first outdoor heat exchanger, for obtaining the refrigerant inlet temperature of the first outdoor heat exchanger; a third temperature sensor is provided at the refrigerant outlet of the first outdoor heat exchanger, for obtaining the refrigerant outlet temperature of the first outdoor heat exchanger; a fourth temperature sensor is provided on the surface of the second indoor heat exchanger, for obtaining the surface temperature of the second indoor heat exchanger.

3. The solar energy heating and cooling combined system according to claim 2, characterized in that: The control module is also used to obtain the tube wall temperature of the first outdoor heat exchanger, the surface temperature of the second indoor heat exchanger, the refrigerant outlet temperature of the first outdoor heat exchanger, and the refrigerant inlet temperature of the first outdoor heat exchanger during the heating season.

4. The solar energy heating and cooling combined system according to claim 3, characterized in that: The control module is further configured to, in response to the heat pipe driving temperature difference being less than a first set value, control the system in an air source heat pump mode and control the second control valve, the fifth control valve, the sixth control valve, and the eighth control valve to be open, and the first control valve, the third control valve, the fourth control valve, the seventh control valve, and the ninth control valve to be closed, so that the compressor and the expansion valve are started, and the fluorine pump is turned off; or, The control module is further configured to, in response to the heat pipe driving temperature difference being greater than or equal to a first set value and the refrigerant inlet and outlet temperature difference being less than or equal to a second set value, control the system in a gravity-type heat pipe operation mode and control the first control valve, the third control valve, the fifth control valve, the sixth control valve, and the ninth control valve to be open, and the second control valve, the fourth control valve, the seventh control valve, and the eighth control valve to be closed, so that the compressor, the expansion valve, and the fluorine pump are all turned off; or, The control module is also used to control the first control valve, the third control valve, the fourth control valve, the sixth control valve and the ninth control valve to open, and the second control valve, the fifth control valve, the seventh control valve and the eighth control valve to close in response to the heat pipe driving temperature difference being greater than or equal to the first set value and the refrigerant inlet and outlet temperature difference being greater than the second set value, so that the fluorine pump is started and the compressor and the expansion valve are closed in the power type heat pipe operation mode.

5. The solar energy heating and cooling combined system according to claim 1, characterized in that: The control module is also used to control the system in vapor compression refrigeration mode during the cooling season, and control the second control valve, the fifth control valve, the sixth control valve and the eighth control valve to open, and the first control valve, the third control valve, the fourth control valve, the seventh control valve and the ninth control valve to close, so that the compressor and the expansion valve are started and the fluorine pump is turned off.

6. The solar energy heating and cooling combined system according to claim 1, characterized in that: The control module is also used to control the system in gravity heat pipe mode during the transition season, and control the first control valve, the third control valve, the fifth control valve, the seventh control valve and the ninth control valve to open, and the second control valve, the fourth control valve, the sixth control valve and the eighth control valve to close, so that the compressor, the expansion valve and the fluorine pump are all turned off.

7. A control method for a combined heating and cooling system utilizing solar energy, characterized in that: The solar energy heating and cooling composite system according to any one of claims 1 to 6 comprises: Get the season type; Select the operation mode of the heating and cooling system according to the season type; Selectively open or close the pipeline where the control valve is located according to the operating mode; The process of selecting the operating mode of the heating and cooling composite system according to the season type includes: in the heating season, obtaining the tube wall temperature of the first outdoor heat exchanger, the surface temperature of the second indoor heat exchanger, the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger; obtaining the heat pipe driving temperature difference according to the difference between the tube wall temperature of the first outdoor heat exchanger and the surface temperature of the second indoor heat exchanger; obtaining the refrigerant inlet and outlet temperature difference according to the difference between the refrigerant outlet temperature of the first outdoor heat exchanger and the refrigerant inlet temperature of the first outdoor heat exchanger; and determining the operating mode of the heating and cooling composite system according to the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference.

8. The control method of the solar energy heating and cooling system according to claim 7, characterized in that: The process of determining the operation mode of the heating and cooling composite system according to the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is less than a first set value, selecting the air source heat pump mode, the second outdoor heat exchanger acts as an evaporator to absorb heat from the air, the working fluid is vaporized and enters the compressor through the refrigerant pipe, the working fluid temperature and pressure increase in the compressor, enters the second indoor heat exchanger, releases heat to the room, condenses into a liquid, is throttled by the expansion valve to a low temperature and low pressure state, and then returns to the second outdoor heat exchanger; or, The process of determining the operation mode of the heating and cooling composite system according to the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is greater than or equal to a first set value, and the refrigerant inlet and outlet temperature difference is less than or equal to a second set value, selecting the gravity type heat pipe operation mode, the first outdoor heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes gas, the density decreases, and enters the second indoor heat exchanger along the refrigerant pipe under the action of buoyancy, after exchanging heat with the indoor cold air, part or all of the working fluid becomes liquid, the density increases, and returns to the first outdoor heat exchanger along the refrigerant pipe under the action of gravity; or, The process of determining the operating mode of the heating and cooling composite system based on the heat pipe driving temperature difference and / or the refrigerant inlet and outlet temperature difference includes: if the heat pipe driving temperature difference is greater than or equal to a first set value, and the refrigerant inlet and outlet temperature difference is greater than a second set value, selecting the dynamic heat pipe operating mode, the first outdoor heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes gas and enters the second indoor heat exchanger through the refrigerant pipe, becomes liquid after exchanging heat with the indoor cold air, and returns to the first outdoor heat exchanger along the refrigerant pipe under the drive of the fluorine pump.

9. The control method of the solar energy heating and cooling system according to claim 7, characterized in that: The process of selecting an operating mode of the combined heating and cooling system according to the seasonal type further includes: in the cooling season, selecting a vapor compression cooling mode, wherein the second indoor heat exchanger acts as an evaporator to absorb heat from the indoor air, and the working fluid is vaporized and enters the compressor, where the temperature and pressure of the working fluid increase, and then enters the second outdoor heat exchanger, where it releases heat to the outdoor air and condenses into a liquid state, and then passes through the expansion valve for throttling and pressure reduction, and then returns to the second indoor heat exchanger; or, The process of selecting the operating mode of the heating and cooling composite system according to the seasonal type also includes: in the transition season, selecting the gravity heat pipe mode, the first outdoor side heat exchanger acts as an evaporator to absorb heat from the solar collector, the working fluid absorbs heat and undergoes a phase change, part or all of the working fluid becomes gas, the density decreases, and enters the first indoor side heat exchanger along the refrigerant pipe under the action of buoyancy. After exchanging heat with tap water, part or all of the working fluid becomes liquid, the density increases, and returns to the first outdoor side heat exchanger along the refrigerant pipe under the action of gravity.

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