Heat exchanger control system and method of controlling the same

Abstract

This invention discloses a heat exchanger control system and its control method, belonging to the field of photovoltaic power generation technology. The heat exchanger control system of this invention includes: a photothermal-electric conversion device, comprising a transparent plate, a solar power generation heat exchange component with heat exchange channels, and a shell with a vacuum chamber. The solar power generation heat exchange component is disposed within the shell, and an opening is provided on one side of the shell. The opening is fitted with a transparent plate that is sealed to and blocks the shell; a four-way valve, having an intake port, an exhaust port, a first interface, and a second interface; and a compressor, the compressor's intake pipe being connected to the intake port. By setting the internal space of the shell to a vacuum state, and by spaced the heat exchange plate and solar cells from the bottom of the shell, the heat conduction area with the shell can be reduced. Therefore, during winter days, heat from sunlight irradiating into the shell can be collected through the heat exchange plate, improving the efficiency of photothermal conversion.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic power generation technology, and more specifically to a heat exchanger control system and its control method. Background Technology

[0002] Solar photovoltaic / thermal (PV / T) technology combines photovoltaics and heat to improve the utilization rate of solar energy. Current PV / T heat pump systems are significantly affected by seasonal variations in system utilization. In summer, with longer sunshine hours and higher temperatures, solar energy can be fully utilized; however, in winter, especially in northern regions and some frigid areas at high altitudes, temperatures are low and sunshine hours are short. Since solar collectors generally have good thermal conductivity, they suffer greater heat loss due to the low external temperature environment, reducing the efficiency of photothermal conversion. Summary of the Invention

[0003] The objective of this invention is to at least solve the problem of low photothermal conversion efficiency in existing PV / T heat pump systems during winter. This objective is achieved through the following technical solution:

[0004] A first aspect of the present invention provides a heat exchanger control system, comprising:

[0005] A photothermal-electric conversion device includes a transparent plate, a solar power generation heat exchange component with a heat exchange channel, and a shell with a vacuum chamber. The solar power generation heat exchange component is disposed inside the shell. An opening is provided on one side of the shell, and the opening is provided with a transparent plate that is sealed to the shell and blocks itself.

[0006] The four-way valve has an intake port, an exhaust port, a first interface, and a second interface.

[0007] The compressor has an intake pipe connected to the intake port and an exhaust pipe connected to the exhaust port.

[0008] The first insulated water tank has a first drain pipe at its bottom and a valve on the first drain pipe.

[0009] The second heat exchange tube is located inside the first insulated water tank. One end of the second heat exchange tube is connected to the first interface through the first pipeline, and the other end is connected to the heat exchange channel through the second pipeline. The outlet of the heat exchange channel is connected to the second interface through the third pipeline. The second heat exchange tube is filled with refrigerant.

[0010] A throttling element is provided on the second pipeline.

[0011] According to the present invention, a photothermal-electric conversion device for a heat exchanger control system is provided, wherein the internal space of the shell is set to a vacuum state, which can reduce the heat conduction area with the shell, thereby collecting the heat irradiated by sunlight into the shell through the heat exchange plate during the daytime in winter, thus improving the efficiency of photothermal conversion.

[0012] In addition, the photothermal-electric conversion device for a heat exchanger control system according to the present invention may also have the following additional technical features:

[0013] In some embodiments of the present invention, the solar power generation heat exchange component includes a solar cell, a photovoltaic backsheet, and a heat exchange plate. The solar cell is disposed inside the housing and spaced apart from the transparent plate. The photovoltaic backsheet is disposed at the bottom of the solar cell. The heat exchange plate is disposed at the bottom of the photovoltaic backsheet and spaced apart from the bottom of the housing. The heat exchange plate forms the heat exchange channel inside.

[0014] In some embodiments of the present invention, the heat exchange channel is provided with a plurality of spaced baffles made of shape memory alloy material, each baffle being connected to the side wall of the heat exchange channel, each baffle having a flat state and a bent state at different temperatures, and the temperature of the flat state being lower than the temperature of the bent state.

[0015] When the baffle is in a straight state, the baffle is in contact with one side of the heat exchange channel;

[0016] When the baffle is in a bent state, the baffle is raised in the heat exchange channel, and the raised end of the baffle and the side wall of the heat exchange channel on the same side as the raised end of the baffle are separated by a gap.

[0017] In some embodiments of the present invention, at least one side wall of the housing is provided with a first heat exchange tube, the first heat exchange tube being used to heat the housing.

[0018] In some embodiments of the present invention, the heat exchanger control system further includes a three-way valve, one outlet of which is connected to the inlet of the first heat exchange tube, and the other outlet of which is connected to the inlet of the heat exchange channel, wherein the first heat exchange tube and the heat exchange channel share a single outlet.

[0019] The other end of the second heat exchange tube is connected to the inlet of the three-way valve through a second pipeline.

[0020] In some embodiments of the present invention, the heat exchanger control system further includes two pressure detection elements respectively located at the inlet and outlet of the heat exchange channel.

[0021] In some embodiments of the present invention, the heat exchanger control system further includes a second insulated water tank, a water pump, a drain valve, and a second drain pipe. The first drain pipe is connected to the second insulated water tank, and a water pump is provided on the first drain pipe. The bottom of the second insulated water tank is connected to the second drain pipe, and a drain valve is provided on the second drain pipe. The height of the second insulated water tank is greater than the height of the first insulated water tank.

[0022] In some embodiments of the present invention, the heat exchanger control system further includes at least one inline generator disposed on the second drain pipe.

[0023] A second aspect of the present invention provides a control method for a heat exchanger control system, the control method being applied to the heat exchanger control system described in the first aspect, the control method comprising:

[0024] The outdoor ambient light intensity and the voltage value of the solar cells of the photothermal-electric conversion device are obtained;

[0025] Based on the condition that the light intensity is greater than or equal to a preset light intensity and the voltage value is less than a preset voltage value, the three-way valve is controlled to switch to the first position to connect the second heat exchange tube with the first heat exchange tube of the photothermal-electric conversion device, and the four-way valve is controlled to adjust to the first reversing position to allow the first heat exchange tube to release heat and the second heat exchange tube to absorb heat, until the voltage value is greater than or equal to the preset voltage value, the four-way valve is controlled to switch to the second reversing position to allow the first heat exchange tube to absorb heat and the second heat exchange tube to release heat.

[0026] According to a control method for a heat exchanger control system of the present invention, when frost and snow accumulate on the transparent plate, it affects the light transmission of the photothermal-electric conversion device. Therefore, it is necessary to remove the frost and snow from the surface of the transparent plate. This problem can be solved by using the first heat exchange tube as the condenser of the heat pump. Specifically, the weather conditions can be judged based on the light intensity. When the weather is good and there is sufficient sunshine, but the voltage value of the solar cells is low, it indicates insufficient light transmission. It is determined that frost or snow has accumulated on the outer surface of the transparent plate, and defrosting or snow removal is required. At this time, the four-way valve can be used to switch the second heat exchange tube, which was originally used as a condenser, to act as an evaporator, and the first heat exchange tube to act as a condenser. The hot water in the water tank is used for heat exchange to perform defrosting or snow removal.

[0027] When the liquid refrigerant in the heat exchange channel is not completely evaporated, the refrigerant at too low a temperature will cause the baffle to deform, with one end tilting up, reducing the cross-sectional area of ​​part of the heat exchange channel. At the same time, it increases the flow resistance and reduces the refrigerant flow rate. The pressure difference between the two ends of the heat exchange channel outlet will change due to the deformation of the baffle. Therefore, the pressure difference between the two ends of the heat exchange channel outlet can be used to determine whether there is a problem of incomplete refrigerant evaporation, and then the operating frequency of the compressor can be adjusted to prevent the generation of a large amount of liquid refrigerant.

[0028] In addition, the control method for a heat exchanger control system according to the present invention may also have the following additional technical features:

[0029] In some embodiments of the present invention, the control method further includes:

[0030] Obtain the pressure value at the inlet of the heat exchange channel and the pressure value at the outlet of the heat exchange channel;

[0031] If the pressure difference between the inlet pressure of the heat exchange channel and the outlet pressure of the heat exchange channel is greater than or equal to a preset pressure difference, the compressor is controlled to run at a first frequency, the three-way valve is controlled to switch to a second position so that the heat exchange channel between the second heat exchange tube and the heat exchange plate is connected, and the second reversing position of the four-way valve remains unchanged.

[0032] If the pressure difference between the inlet pressure of the heat exchange channel and the outlet pressure is less than a preset pressure difference, the compressor is controlled to operate at a second frequency, and the second reversing position of the four-way valve is kept unchanged, wherein the first frequency is less than the second frequency. Attached Figure Description

[0033] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0034] Figure 1 A schematic diagram of the piping of an embodiment of the heat exchanger control system of the present invention is shown.

[0035] Figure 2 An internal structural view of an embodiment of the photothermoelectric conversion device of the present invention is shown schematically.

[0036] Figure 3 An internal structural view of yet another embodiment of the photothermoelectric conversion device of the present invention is shown schematically.

[0037] Figure 4An isometric view schematically illustrating an embodiment of the photothermoelectric conversion device of the present invention is shown.

[0038] Figure 5 A cross-sectional view of an embodiment of the heat exchange channel on the heat exchange plate of the present invention is shown schematically.

[0039] Figure 6 A schematic partial longitudinal cross-sectional view of an embodiment of the heat exchange channel on the heat exchange plate of the present invention is shown with the baffles in a straight state.

[0040] Figure 7 A schematic partial longitudinal cross-sectional view of an embodiment of the heat exchange channel on the heat exchange plate of the present invention is shown in a bent and warped state.

[0041] Figure 8 A flowchart illustrating the control method of the heat exchanger control system of the present invention is shown schematically.

[0042] The attached figures are labeled as follows:

[0043] 10. Photothermal-electric conversion device; 11. Housing; 11a. Mounting groove; 11b. Inner shell; 11c. Outer shell; 12. Transparent plate; 13. Solar cell; 14. EVA film; 15. Photovoltaic backsheet; 16. Heat exchange plate; 161. Heat exchange channel; 162. Baffle; 17. Three-way valve; 18. First heat exchange tube;

[0044] 20. Four-way valve; 30. Compressor; 40. First insulated water tank; 50. Second insulated water tank; 60. Second heat exchange tube; 70. Throttling element; 80. Pressure detection element; 90. Water pump; 100. Drain valve; 110. Second drain pipe; 120. Pipeline generator; 130. Valve; 140. Inlet pipe; 150. Inlet valve. Detailed Implementation

[0045] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0046] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0047] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0048] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented as "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0049] According to an embodiment of the present invention, a heat exchanger control system is proposed, such as... Figures 1-3As shown, the device includes a photothermal-electric conversion device 10, a four-way valve 20, a compressor 30, a first insulated water tank 40, a second heat exchange tube 60, and a throttling element 70. The photothermal-electric conversion device 10 includes a transparent plate 12, a solar power generation heat exchange component with a heat exchange channel 161, and a shell 11 with a vacuum chamber. The solar power generation heat exchange component is disposed inside the shell 11. An opening is provided on one side of the shell 11, and the opening is fitted with a transparent plate 12 that is sealed to and blocks the shell 11. The four-way valve 20 has an intake port, an exhaust port, a first interface, and a second interface; the intake pipe of the compressor 30 is connected to the intake port, and the exhaust pipe of the compressor 30 is connected to the exhaust port; the bottom of the first insulated water tank 40 is provided with a first drain pipe, and a valve 130 is provided on the first drain pipe; the second heat exchange tube 60 is located inside the first insulated water tank 40, one end of the second heat exchange tube 60 is connected to the first interface through the first pipe, and the other end of the second heat exchange tube 60 is connected to the heat exchange channel 161 through the second pipe; the outlet of the heat exchange channel 161 is connected to the second interface through a third pipe; the second heat exchange tube 60 is filled with refrigerant. A throttling element 70 is located on the second pipe.

[0050] In one embodiment, the transparent plate 12 can be a glass plate or a plastic plate. The glass plate can be selected from glass with good light transmittance, and a TiO2 film can be provided on the side of the transparent plate 12 facing the outside of the housing 11, so that the surface of the transparent plate 12 can have a good smoothness. TiO2 itself can act as a photocatalyst to remove dust, thereby reducing the light reflectivity and ensuring good light transmittance.

[0051] The four-way valve 20, compressor 30, second heat exchange tube 60, throttling element 70, heat exchange plate 16, first pipeline, second pipeline, and third pipeline form a heat pump system. An oil-gas separation device can be installed on the heat pump system, specifically on the exhaust side pipeline of the compressor 30. This oil-gas separation device is existing technology and not the focus of this invention; therefore, it will not be described in detail here.

[0052] The throttling element 70 can be a throttling valve or an expansion valve.

[0053] The photothermal-electric conversion device 10 converts a portion of the light into electrical energy to generate electricity, while the remaining portion is collected and stored as heat in the first insulated water tank 40 for daily use. Especially in winter, when the ambient temperature is low, the internal space of the shell is set to a vacuum state, which reduces the heat conduction area with the shell, thereby reducing heat loss during thermal radiation and improving the efficiency of photothermal conversion.

[0054] In one embodiment, such as Figure 2 and Figure 3As shown, the solar power generation heat exchange module includes solar cells 13, a photovoltaic backsheet 15, and a heat exchange plate 16. The solar cells 13 are disposed inside the housing 11 and spaced apart from the transparent plate 12; the photovoltaic backsheet 15 is disposed at the bottom of the solar cells 13; the heat exchange plate 16 is disposed at the bottom of the photovoltaic backsheet 15 and spaced apart from the bottom of the housing 11, and a heat exchange channel 161 is formed inside the heat exchange plate 16.

[0055] An EVA film 14 (ethylene-vinyl acetate copolymer) can be coated on both sides of the solar cell 13. The EVA film 14 not only has good light transmittance, but also has the characteristics of corrosion resistance and moisture resistance, which can protect the solar cell 13.

[0056] The photovoltaic backsheet 15 is located at the bottom of the solar cell 13, meaning that the solar cell 13 coated with EVA film 14 is attached to one side of the photovoltaic backsheet 15, and the solar cell 13 is located between the transparent plate 12 and the photovoltaic backsheet 15.

[0057] The heat exchange channel 161 is filled with a refrigerant having a low evaporation temperature. The heat exchange channel 161 is connected to a heat pump system and can be used as a condenser or evaporator for the system. This allows the photothermal-electric conversion device 10 to collect solar heat even in winter. The refrigerant can be, but is not limited to, R22, R134a, R404a, etc. Optionally, the heat exchange channel 161 can be a serpentine heat exchange channel.

[0058] By setting the internal space of the housing 11 to a vacuum state, and by setting the heat exchange plate 16 and the solar cell 13 at intervals from the bottom of the housing 11, the heat conduction area with the housing 11 can be further reduced. Thus, during the daytime in winter, most of the heat radiated by sunlight into the housing 11 can be collected through the heat exchange plate 16, further reducing the heat loss transferred from the photovoltaic backsheet 15 to the heat exchange plate 16, thereby improving the efficiency of photothermal conversion.

[0059] In some embodiments of the present invention, such as Figures 4-6 As shown, the heat exchange channel 161 is provided with a plurality of spaced baffles 162 made of shape memory alloy material. Each baffle 162 is connected to the side wall of the heat exchange channel 161. Each baffle 162 has a flat state and a bent state at different temperatures, and the temperature of the flat state is lower than the temperature of the bent state.

[0060] When the baffle 162 is in a straight position, the baffle 162 is in contact with one side of the heat exchange channel 161;

[0061] When the baffle 162 is in a bent state, the baffle 162 is raised inside the heat exchange channel 161, and the raised end of the baffle 162 and the side wall of the heat exchange channel 161 on the same side as the raised end of the baffle 162 are separated by a gap.

[0062] One end of the baffle 162 can be welded or connected to a side wall of the heat exchange channel 161 by screws, while the other end is a free end and is in a straight state when no phase change occurs.

[0063] Baffle 162 can be made of shape memory alloy material that undergoes a phase change at low temperatures, such as Ni-Ti alloys like NiTiFe3, NiTiCr3, and TiNiFeV. Taking NiTiFe3 as an example, its phase change temperature is around -36.5℃. The heat exchanger control system operates at low pressure, approximately 0.15-0.25 MPa. The refrigerant evaporation temperature is low, causing baffle 162 to deform and warp. In summer, when the ambient temperature is higher, the heat pump system can operate at high pressure, above 1.2 MPa. At this pressure, the refrigerant evaporation temperature is higher than the phase change temperature of baffle 162, keeping it in a flat state.

[0064] In some embodiments of the present invention, such as Figure 2 and Figure 3 As shown, at least one side wall of the housing 11 is provided with a first heat exchange tube 18, which is used to heat the housing 11.

[0065] In some embodiments of the present invention, such as Figure 1 and Figure 2 As shown, the housing 11 has two sets of spaced columns inside, and each set of columns is fixed with a mounting groove 11a. The solar cell 13, photovoltaic backsheet 15 and heat exchange plate 16 are embedded in the mounting grooves 11a of the two sets of columns, which can reduce the contact area between the solar cell 13, photovoltaic backsheet 15 and heat exchange plate 16 and the housing 11, and reduce the heat loss in the photothermal conversion process.

[0066] Optional, such as Figure 3 As shown, the shell 11 can be, but is not limited to, a double-layer shell 11, that is, the shell 11 has an inner shell 11b and an outer shell 11c, and a first heat exchange tube 18 is arranged in the space between the inner shell 11b and the outer shell 11c. The first heat exchange tube 18 transfers heat to the transparent plate 12 for defrosting or snow removal.

[0067] When defrosting or snow removal is required, the first heat exchange tube 18 can be used as a condenser for the heat pump system.

[0068] In some embodiments of the present invention, such as Figure 3 As shown, the photothermal-electric conversion device 10 also includes a three-way valve 17. One outlet of the three-way valve 17 is connected to the inlet of the first heat exchange tube 18, and the other outlet of the three-way valve 17 is connected to the inlet of the heat exchange channel 161. The first heat exchange tube 18 and the heat exchange channel 161 share a common outlet. The other end of the second heat exchange tube 60 is connected to the inlet of the three-way valve 17 through a second pipeline.

[0069] The three-way valve 17 can be a solenoid valve or a manual valve; a solenoid valve is more convenient for control.

[0070] The three-way valve 17 allows for the switching of refrigerant between the first heat exchange tube 18 and the heat exchange channel 161. When defrosting or snow removal is required, the vacuum inside the casing 11 makes it difficult to transfer heat to the transparent plate 12 for defrosting or snow removal through the heat exchange channel 161. To address this issue, a first heat exchange tube 18 is installed on the side wall of the casing 11. Heat is transferred to the transparent plate 12 through heat conduction between the first heat exchange tube 18 and the casing 11. Alternatively, a thermally conductive metal strip or plate can be installed on the casing 11 to facilitate heat transfer through contact with the transparent plate 12. The casing 11 can also be made of metal. No specific limitations are specified here.

[0071] In some embodiments of the present invention, the heat exchanger control system further includes two pressure sensing elements 80 respectively located at the inlet and outlet of the heat exchange channel 161. The pressure sensing elements 80 may be pressure sensors or pressure gauges.

[0072] The pressure at the inlet and outlet of the heat exchange plate 16 can be detected by the pressure detection element 80. When the heat exchange system is running in winter and summer, the state of the baffle 162 is different, and the pressure difference between the inlet and outlet of the heat exchange plate 16 is also different. The operating frequency of the compressor 30 can be automatically adjusted according to the pressure difference between the inlet and outlet of the heat exchange plate 16 to meet the normal operation of the system in winter and summer.

[0073] The photothermal-electric conversion device 10 is integrated with a heat pump system. Through the switching of the three-way valve 17 and the four-way valve 20, the photothermal-electric conversion device 10 can perform defrosting and snow removal functions in winter. Specifically, the first heat exchange tube 18 and the second heat exchange tube 60 are connected. The first heat exchange tube 18 acts as a condenser to release heat, using the heated water in the first insulated water tank 40 as the heat source. The second heat exchange tube 60 acts as an evaporator to absorb heat, and the refrigerant after heat absorption is transported to the first heat exchange tube 18 to release heat, defrosting or melting snow on the transparent plate 12. When the heat exchanger control system is running, the refrigerant in the heat exchange plate 16 may not evaporate completely due to its low heat absorption. In winter, when the refrigerant temperature of the heat exchange plate 16 is too low, the baffle 162 on the photothermal-electric conversion device 10 will deform and tilt upwards due to the low temperature, so as to reduce the flow of refrigerant entering the heat exchange channel 161, so that the refrigerant can fully absorb heat and evaporate and flow back into the compressor 30, increasing the heat exchange time to ensure full conversion of photothermal energy. At the same time, it also avoids the problem of liquid slugging caused by a large amount of liquid refrigerant entering the compressor 30.

[0074] In some embodiments of the present invention, such as Figure 1As shown, the heat exchanger control system also includes a second insulated water tank 50, a water pump 90, a drain valve 100, and a second drain pipe 110. The first drain pipe is connected to the second insulated water tank 50, and the water pump 90 is installed on the first drain pipe. The bottom of the second insulated water tank 50 is connected to the second drain pipe 110, and the drain valve 100 is installed on the second drain pipe 110. The height of the second insulated water tank 50 is greater than the height of the first insulated water tank 40.

[0075] When the first insulated water tank 40 is full, during the day, the heat exchange plate 16 acts as the evaporator of the heat pump system to absorb heat. The high-temperature, high-pressure refrigerant discharged from the compressor 30 enters the second heat exchange tube 60 inside the first insulated water tank 40 to heat the water. When the water boils, excess heat cannot be absorbed and stored. To store this excess heat, the water in the first insulated water tank 40 is pumped to the second insulated water tank 50 by the water pump 90, and tap water is injected into the first insulated water tank 40 for reheating. The water in the second insulated water tank 50 can be stored for users' domestic use. The height of the second insulated water tank 50 is greater than that of the first insulated water tank 40, allowing water to be stored using potential energy. During use, the water flows out due to gravity.

[0076] In one embodiment, the first insulated water tank 40 is further provided with a water inlet pipe 140, and the water inlet pipe 140 is provided with a water inlet valve 150. The water inlet pipe 140 can inject tap water into the first insulated water tank 40.

[0077] In one embodiment, a liquid level sensor can be installed near the top of the first insulated water tank 40 to monitor the water level in the first insulated water tank 40 and prevent water overflow during the filling process.

[0078] In one embodiment, the heat exchanger control system further includes at least one inline generator 120 disposed on the second drain line 110. Potential energy can be converted into electrical energy for use by the heat exchanger control system or by the user.

[0079] The heat exchanger control system also includes a battery. Solar panels 13 and a tubular generator 120 are connected to the battery charger to charge the battery and store excess electrical energy for normal operation of the heat exchanger control system. The battery can power the heat exchanger control system; multiple batteries can be used, with some providing power during operation and others storing excess energy for backup.

[0080] According to an embodiment of the present invention, a control method for a heat exchanger control system is proposed, wherein the control method is applied to the heat exchanger control system, such as... Figure 8 As shown, the control method may include steps S1-S5, as detailed below:

[0081] S1. Obtain the outdoor ambient light intensity and the voltage value of the solar cell 13 of the photothermal-electric conversion device 10.

[0082] Pressure gauges can be installed at the positive and negative terminals of the output end of the solar cell 13 to monitor the pressure value.

[0083] Light sensors can be installed in outdoor environments to monitor the intensity of light in those environments.

[0084] S2. Based on the light intensity being greater than or equal to the preset light intensity and the voltage value being less than the preset voltage value, control the three-way valve 17 to switch to the first position so that the second heat exchange tube 60 is connected to the first heat exchange tube 18 of the photothermal-electric conversion device 10, and control the four-way valve 20 to adjust to the first reversing position so that the first heat exchange tube 18 releases heat and the second heat exchange tube 60 absorbs heat, until the voltage value is greater than or equal to the preset voltage value, control the four-way valve 20 to switch to the second reversing position so that the first heat exchange tube 18 absorbs heat and the second heat exchange tube 60 releases heat.

[0085] If the light intensity is greater than or equal to the preset light intensity, it indicates that the heat exchanger control system can collect light energy. If the voltage value is less than the preset voltage value, it indicates that less light passes through the transparent plate 12 and reaches the solar cell 13, and there is snow or frost accumulation on the outer surface of the transparent plate 12, requiring defrosting. At this time, the three-way valve 17 is controlled so that the first heat exchange tube 18 acts as the heat source, and the second heat exchange tube 60 acts as the heat absorber, absorbing the heat from the heated hot water to defrost or melt the snow.

[0086] Once the voltage value is greater than or equal to the preset voltage value, the heat exchanger control system switches to normal operating mode for photoelectric and photothermal conversion. Switching the heat exchanger control system to normal operating mode means that heat exchange plate 16 acts as the heat absorption source (evaporator), and the second heat exchange tube 60 acts as the heat release source (condenser).

[0087] S3. Obtain the pressure value at the inlet of heat exchange channel 161 and the pressure value at the outlet of heat exchange channel 161.

[0088] A pressure sensor can be installed at the inlet and outlet of the heat exchange channel 161 for measurement. The pressure value measured at the inlet of the heat exchange channel 161 is P1, and the pressure value measured at the outlet of the heat exchange channel 161 is P2.

[0089] S4. Based on the fact that the pressure difference between the inlet pressure value and the outlet pressure value of the heat exchange channel 161 is greater than or equal to the preset pressure difference value, i.e., P1-P2≥ΔP, where ΔP is the preset pressure difference value; control the compressor 30 to run at the first frequency, control the three-way valve 17 to switch to the second position so that the second heat exchange tube 60 and the heat exchange channel 161 of the heat exchange plate 16 are connected, and maintain the second reversing position of the four-way valve 20 unchanged.

[0090] During the operation of the heat exchanger control system, the inlet pressure of heat exchange channel 161 is greater than the outlet pressure. This is due to the pressure loss of the refrigerant within the heat exchange pipe. In winter, the ambient temperature is low, and the temperature difference between the refrigerant evaporation temperature in heat exchange channel 161 and the ambient temperature is small, resulting in a longer evaporation time. If the flow velocity in heat exchange channel 161 is high, incomplete evaporation of the refrigerant may occur, leading to a large amount of liquid refrigerant, affecting the operation of the entire system. The baffles 162 in heat exchange channel 161 can undergo a phase change at low temperatures, tilting upwards to increase the flow resistance of heat exchange channel 161, thereby reducing the refrigerant flow rate and allowing the refrigerant to spend more time in heat exchange channel 161, facilitating the full absorption of heat generated by sunlight. At this time, the pressure difference between the inlet and outlet of heat exchange channel 161 will further increase. By monitoring the pressure at the inlet and outlet of heat exchange channel 161, it is possible to determine whether there is liquid accumulation in the refrigerant within heat exchange channel 161. When P1-P2≥ΔP, it is determined that liquid may accumulate in heat exchange channel 161. It is necessary to reduce the operating frequency of compressor 30 to reduce the operating pressure of the heat exchanger control system and reduce the generation of a large amount of liquid.

[0091] S5. Based on the fact that the pressure difference between the inlet pressure of heat exchange channel 161 and the outlet pressure of heat exchange channel 161 is less than the preset pressure difference, i.e., P1-P2<ΔP; control the compressor 30 to run at the second frequency and maintain the second reversing position of the four-way valve 20 unchanged, wherein the first frequency is less than the second frequency.

[0092] At this time, the refrigerant in the heat exchange channel 161 can be completely evaporated. Especially in summer, the refrigerant evaporation temperature is high, the baffle 162 will not deform, and the flow resistance of the heat exchange channel 161 is relatively low.

[0093] In steps S1-S2, defrosting or snow removal is required before proceeding to steps S3-S5. If there is significant snow or frost accumulation on the transparent plate 12, less sunlight will pass through, generating less heat and causing incomplete evaporation of the refrigerant within the heat exchange channel 161. This results in a lower temperature in the heat exchange channel 161. Furthermore, the raised baffle 162 increases the flow resistance of the refrigerant and leads to a larger pressure difference between the inlet and outlet of the heat exchange channel 161. Therefore, defrosting or snow removal must be completed before proceeding to steps S3-S5 to determine if there is a problem with the complete evaporation of the refrigerant on the heat exchange plate 16.

[0094] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A heat exchanger control system, characterized by, include: A photothermal-electric conversion device includes a transparent plate, a solar power generation heat exchange component with a heat exchange channel, and a shell with a vacuum chamber. The solar power generation heat exchange component is disposed inside the shell. An opening is provided on one side of the shell, and the opening is provided with a transparent plate that is sealed to the shell and blocks itself. The four-way valve has an intake port, an exhaust port, a first interface, and a second interface. The compressor has an intake pipe connected to the intake port and an exhaust pipe connected to the exhaust port. The first insulated water tank has a first drain pipe at its bottom and a valve on the first drain pipe. The second heat exchange tube is located inside the first insulated water tank. One end of the second heat exchange tube is connected to the first interface through the first pipeline, and the other end is connected to the heat exchange channel through the second pipeline. The outlet of the heat exchange channel is connected to the second interface through the third pipeline. The second heat exchange tube is filled with refrigerant. A throttling element is provided on the second pipeline; The heat exchange channel is provided with multiple spaced baffles made of shape memory alloy material. Each baffle is connected to the side wall of the heat exchange channel. Each baffle has a flat state and a bent state at different temperatures, and the temperature of the flat state is higher than the temperature of the bent state. When the baffle is in a straight state, the baffle is in contact with one side of the heat exchange channel; When the baffle is in a bent state, the baffle is raised in the heat exchange channel, and the raised end of the baffle and the side wall of the heat exchange channel on the same side as the raised end of the baffle are separated by a gap.

2. The heat exchanger control system of claim 1, wherein, The solar power generation heat exchange component includes solar cells, a photovoltaic backsheet, and a heat exchange plate. The solar cells are disposed inside the housing and spaced apart from the transparent plate. The photovoltaic backsheet is disposed at the bottom of the solar cells. The heat exchange plate is disposed at the bottom of the photovoltaic backsheet and spaced apart from the bottom of the housing. The heat exchange plate forms the heat exchange channel inside.

3. The heat exchanger control system of claim 1, wherein, At least one side wall of the housing is provided with a first heat exchange tube, which is used to heat the housing.

4. The heat exchanger control system of claim 3, wherein, The heat exchanger control system also includes a three-way valve, one outlet of which is connected to the inlet of the first heat exchange tube, and the other outlet of which is connected to the inlet of the heat exchange channel. The first heat exchange tube and the heat exchange channel share a single outlet. The other end of the second heat exchange tube is connected to the inlet of the three-way valve through a second pipeline.

5. The heat exchanger control system of claim 4, wherein, The heat exchanger control system also includes two pressure detection elements located at the inlet and outlet of the heat exchange channel, respectively.

6. The heat exchanger control system according to claim 5, characterized in that, The heat exchanger control system also includes a second insulated water tank, a water pump, a drain valve, and a second drain pipe. The first drain pipe is connected to the second insulated water tank and is equipped with a water pump. The bottom of the second insulated water tank is connected to the second drain pipe, and a drain valve is provided on the second drain pipe. The height of the second insulated water tank is greater than the height of the first insulated water tank.

7. The heat exchanger control system of claim 6, wherein, The heat exchanger control system also includes at least one inline generator installed on the second drain pipe.

8. A control method of a heat exchanger control system, the control method being applied to the heat exchanger control system according to any one of claims 5 to 7, characterized by The control method includes: The outdoor ambient light intensity and the voltage value of the solar cells of the photothermal-electric conversion device are obtained; Based on the condition that the light intensity is greater than or equal to a preset light intensity and the voltage value is less than a preset voltage value, the three-way valve is controlled to switch to the first position to make the second heat exchange tube connect with the first heat exchange tube of the photothermal-electric conversion device, and the four-way valve is controlled to adjust to the first reversing position to make the first heat exchange tube release heat and the second heat exchange tube absorb heat, until the voltage value is greater than or equal to the preset voltage value, the four-way valve is controlled to switch to the second reversing position to make the first heat exchange tube absorb heat and the second heat exchange tube release heat.

9. The control method according to claim 8, characterized by, The control method further includes: Obtain the pressure value at the inlet of the heat exchange channel and the pressure value at the outlet of the heat exchange channel; If the pressure difference between the inlet pressure of the heat exchange channel and the outlet pressure of the heat exchange channel is greater than or equal to a preset pressure difference, the compressor is controlled to run at a first frequency, the three-way valve is controlled to switch to a second position to make the second heat exchange tube connected to the heat exchange channel, and the second reversing position of the four-way valve is kept unchanged. If the pressure difference between the inlet pressure of the heat exchange channel and the outlet pressure is less than a preset pressure difference, the compressor is controlled to operate at a second frequency, and the second reversing position of the four-way valve is kept unchanged, wherein the first frequency is less than the second frequency.

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