Photovoltaic temperature adjusting system and method utilizing waste heat of combined cycle unit

Abstract

The invention provides a photovoltaic temperature adjusting system and method utilizing waste heat of a combined cycle unit. The system comprises the combined cycle unit, a photovoltaic assembly and a temperature adjusting assembly. The flue gas waste heat recovery heat exchanger is used for recovering flue gas heat energy through a first heat exchange fluid; the temperature adjusting assembly comprises a first heat exchanger and a second heat exchanger. The first heat exchanger is connected with the photovoltaic module; the first input end of the second heat exchanger is connected with the output end of the flue gas waste heat recovery heat exchanger, and the first output end of the second heat exchanger is connected with the input end of the flue gas waste heat recovery heat exchanger; the second input end of the second heat exchanger is connected with the output end of the first heat exchanger, and the second output end of the second heat exchanger is connected with the input end of the first heat exchanger. One technical effect of the invention is that not only is the photoelectric conversion efficiency enhanced by reasonably regulating and controlling the working temperature of the photovoltaic module, but also the low-temperature heat energy of the exhaust smoke of the waste heat boiler unit is recovered, and the heat efficiency of the waste heat boiler unit is improved.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic power generation technology, specifically relating to a photovoltaic temperature regulation system and method that utilizes waste heat from a combined cycle unit. Background Technology

[0002] As the penetration rate of photovoltaic (PV) power generation technology in new power system installations continues to rise, its inherent intermittency and volatility pose a severe challenge to the stable operation of the power grid. Against this backdrop, gas-steam combined cycle (GSCB) units, with their rapid start-up and shutdown capabilities and wide load regulation range, have become a major choice for flexible power sources due to their high efficiency, low carbon emissions, and environmental advantages. The coupling of PV power generation technology with GSCB units to form distributed energy systems will be an important future development trend in the power generation field. However, both technologies have some drawbacks when operating independently. The performance of PV modules is closely related to their operating temperature. If the operating temperature of PV modules is too high, for example, for every 1°C increase, the photoelectric conversion efficiency will decrease by 0.3% to 0.5%. Furthermore, if the local temperature difference is too large, a hot spot effect will occur, severely damaging the lifespan of the PV modules. Conversely, if the operating temperature of PV modules is too low, surface icing or snow accumulation will not only affect light absorption and reduce photoelectric conversion efficiency but may also alter the physical properties of the materials, affecting the module's lifespan. In addition, the energy loss of combined cycle units mainly comes from the flue gas loss of the waste heat boiler and the cold end loss of the condenser. In order to avoid low-temperature corrosion, the flue gas temperature of the waste heat boiler is usually greater than 90°C. The water in the flue gas mainly exists in the form of water vapor, which contains a large amount of latent heat of vaporization. Directly discharging it into the air will result in a huge waste of heat energy.

[0003] In summary, there is an urgent need for a photovoltaic temperature control system and method that utilizes the waste heat of combined cycle units in distributed energy systems. This system should be able to reasonably regulate the operating temperature of photovoltaic modules and recover and utilize the flue gas heat energy from the waste heat boiler in the combined cycle unit, thereby greatly improving the overall energy utilization efficiency of distributed energy systems. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art, and to provide a new technical solution for a photovoltaic temperature control system and method that utilizes waste heat from a combined cycle unit.

[0005] According to a first aspect of the present invention, a photovoltaic temperature control system utilizing waste heat from a combined cycle unit is provided, comprising:

[0006] A combined cycle unit, the combined cycle unit including a flue gas waste heat recovery heat exchanger, the flue gas waste heat recovery heat exchanger being used to recover flue gas heat energy through a first heat exchange fluid;

[0007] The photovoltaic module and the temperature control module are provided. The temperature control module includes a first heat exchanger and a second heat exchanger. The first heat exchanger is connected to the photovoltaic module for heat exchange. The first input terminal of the second heat exchanger is connected to the output terminal of the flue gas waste heat recovery heat exchanger, and the first output terminal of the second heat exchanger is connected to the input terminal of the flue gas waste heat recovery heat exchanger. The second input terminal of the second heat exchanger is connected to the output terminal of the first heat exchanger, and the second output terminal of the second heat exchanger is connected to the input terminal of the first heat exchanger.

[0008] When the temperature of the photovoltaic module is lower than the first preset temperature, the first heat exchange fluid heats the second heat exchange fluid circulating through the first and second heat exchangers in the second heat exchanger, so as to heat the photovoltaic module.

[0009] Optionally, the temperature control assembly further includes a lithium bromide refrigeration unit;

[0010] The first input terminal of the lithium bromide chiller is connected to the output terminal of the flue gas waste heat recovery heat exchanger, and the first output terminal of the lithium bromide chiller is connected to the input terminal of the flue gas waste heat recovery heat exchanger; the second input terminal of the lithium bromide chiller is connected to the output terminal of the first heat exchanger, and the second output terminal of the lithium bromide chiller is connected to the input terminal of the first heat exchanger.

[0011] When the temperature of the photovoltaic module is higher than the second preset temperature, the first heat exchange fluid is cooled down by the lithium bromide refrigeration unit and then the second heat exchange fluid circulating through the first heat exchanger and the lithium bromide refrigeration unit is cooled down to cool the photovoltaic module; wherein, the second preset temperature is higher than the first preset temperature.

[0012] Optionally, the temperature control component further includes a heat storage device;

[0013] The output end of the heat storage device is connected to the input end of the flue gas waste heat recovery heat exchanger.

[0014] The first heat exchange fluid circulates through the flue gas waste heat recovery heat exchanger and the heat storage device to store heat in the heat storage device.

[0015] Optionally, the combined cycle unit further includes a gas turbine unit, a waste heat boiler unit, and a steam turbine unit; wherein the waste heat boiler unit is connected to the flue gas waste heat recovery heat exchanger;

[0016] The gas turbine unit is connected to the waste heat boiler unit; the waste heat boiler unit is connected to the steam turbine unit.

[0017] The gas turbine unit uses natural gas to generate high-temperature and high-pressure gas for power generation. After completing its work, the gas enters the waste heat boiler unit and exchanges heat with water in stages to generate high-temperature and high-pressure steam of different grades. The heat of the flue gas in the waste heat boiler unit is recovered through the flue gas waste heat recovery heat exchanger.

[0018] The steam turbine unit uses high-temperature and high-pressure steam of different grades generated by the waste heat boiler unit to generate electricity.

[0019] Optionally, the gas turbine unit includes a compressor, a combustion chamber, a turbine, and a first generator;

[0020] Air is compressed by the compressor in the gas turbine unit and then enters the combustion chamber to mix with natural gas and burn to form high-temperature and high-pressure gas, which drives the turbine to do work and drive the first generator to generate electricity.

[0021] Optionally, the steam turbine unit includes a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder, a second generator, a condenser, and a condensate pump;

[0022] The high-temperature and high-pressure steam of different grades generated by the waste heat boiler unit enters the high-pressure cylinder, medium-pressure cylinder and low-pressure cylinder in sequence to do work and drive the second generator to generate electricity; the exhaust steam after doing work enters the condenser to condense into water, and is then transported to the waste heat boiler unit for recycling via the condensate pump.

[0023] Optionally, the second heat exchanger and the lithium bromide refrigeration unit are respectively connected to the heat storage device;

[0024] The heat stored in the heat storage device can heat the second heat exchange fluid that circulates through the first and second heat exchangers in the second heat exchanger, thereby heating the photovoltaic module.

[0025] The heat stored in the heat storage device can also be cooled in the lithium bromide refrigeration unit to cool the second heat exchange fluid that circulates through the first heat exchanger and the lithium bromide refrigeration unit, thereby cooling the photovoltaic module.

[0026] According to a second aspect of the present invention, a photovoltaic temperature control method utilizing waste heat from a combined cycle unit is provided, applied to a photovoltaic temperature control system utilizing waste heat from a combined cycle unit as described in the first aspect, comprising the following steps:

[0027] The heat energy of the flue gas is recovered through the first heat exchange fluid;

[0028] When the temperature of the photovoltaic module is lower than the first preset temperature, the first heat exchange fluid that recovers the heat energy of the flue gas heats the second heat exchange fluid that circulates through the first heat exchanger and the second heat exchanger in the second heat exchanger, so as to heat the photovoltaic module.

[0029] When the temperature of the photovoltaic module is higher than the second preset temperature, the first heat exchange fluid that recovers the heat energy of the flue gas is cooled down by the lithium bromide refrigeration unit and then used to cool down the second heat exchange fluid that circulates through the first heat exchanger and the lithium bromide refrigeration unit, so as to cool down the photovoltaic module; wherein, the second preset temperature is higher than the first preset temperature.

[0030] Optionally, the first heat exchange fluid that recovers the heat energy from the flue gas circulates through the heat storage device to store the heat in the heat storage device.

[0031] Optionally, when the temperature of the photovoltaic module is lower than the first preset temperature, the heat stored in the heat storage device heats the second heat exchange fluid circulating through the first heat exchanger and the second heat exchanger in the second heat exchanger, so as to heat the photovoltaic module.

[0032] When the temperature of the photovoltaic module is higher than the second preset temperature, the heat stored in the heat storage device is cooled down in the lithium bromide refrigeration unit and then used to cool down the second heat exchange fluid that circulates through the first heat exchanger and the lithium bromide refrigeration unit, so as to cool down the photovoltaic module.

[0033] One technical advantage of this invention is that:

[0034] In this embodiment of the application, when the temperature of the photovoltaic module is lower than the first preset temperature, the first heat exchange fluid heats the second heat exchange fluid circulating through the first heat exchanger and the second heat exchanger in the second heat exchanger, so as to heat the photovoltaic module.

[0035] Therefore, the photovoltaic temperature control system and method utilizing the waste heat of the combined cycle unit can enhance the photoelectric conversion efficiency by reasonably controlling the operating temperature of the photovoltaic modules, avoid the hot spot effect caused by excessive local temperature difference and surface icing or snow accumulation, and improve the service life of the photovoltaic modules.

[0036] Furthermore, the photovoltaic temperature control system and method utilizing the waste heat of the combined cycle unit recovers the low-temperature heat energy from the exhaust gas of the waste heat boiler unit, improves the thermal efficiency of the waste heat boiler unit, reduces the energy loss of the combined cycle unit, and thus improves the overall efficiency of the combined cycle unit.

[0037] In addition, the photovoltaic temperature control system and method that utilizes the waste heat of the combined cycle unit can achieve deep coupling between photovoltaic modules and the combined cycle unit under various operating modes, effectively improving the inherent shortcomings of the two power generation technologies and greatly enhancing the comprehensive energy utilization efficiency of the distributed energy system. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of a photovoltaic temperature control system utilizing waste heat from a combined cycle unit, according to an embodiment of the present invention.

[0039] Figure 2 This is a schematic diagram of a photovoltaic temperature control system utilizing waste heat from a combined cycle unit, according to an embodiment of the present invention.

[0040] In the diagram: 1. Photovoltaic module; 2. First heat exchanger; 3. Lithium bromide refrigeration unit; 4. Second heat exchanger; 5. Thermal storage device; 6. First circulating pump; 7. First valve; 8. Second valve; 9. Third valve; 10. Fourth valve; 11. Fifth valve; 12. Sixth valve; 13. Second circulating pump; 14. Third circulating pump; 15. Flue gas waste heat recovery heat exchanger; 16. Compressor; 17. Combustion chamber; 18. Turbine; 19. First generator; 20. Waste heat boiler unit; 21. High-pressure cylinder; 22. Medium-pressure cylinder; 23. Low-pressure cylinder; 24. Second generator; 25. Condenser; 26. Condensate pump. Detailed Implementation

[0041] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0042] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0043] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0044] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0045] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0046] According to a first aspect of the invention, see Figure 1 A photovoltaic temperature control system utilizing waste heat from a combined cycle unit is provided, comprising:

[0047] A combined cycle unit, the combined cycle unit including a flue gas waste heat recovery heat exchanger 15, the flue gas waste heat recovery heat exchanger 15 being used to recover flue gas heat energy through a first heat exchange fluid;

[0048] The photovoltaic module 1 and the temperature control component include a first heat exchanger 2 and a second heat exchanger 4. The first heat exchanger 2 is connected to the photovoltaic module 1 for heat exchange. The first input terminal of the second heat exchanger 4 is connected to the output terminal of the flue gas waste heat recovery heat exchanger 15, and the first output terminal of the second heat exchanger 4 is connected to the input terminal of the flue gas waste heat recovery heat exchanger 15. The second input terminal of the second heat exchanger 4 is connected to the output terminal of the first heat exchanger 2, and the second output terminal of the second heat exchanger 4 is connected to the input terminal of the first heat exchanger 2.

[0049] When the temperature of the photovoltaic module 1 is lower than the first preset temperature, the first heat exchange fluid heats the second heat exchange fluid circulating through the first heat exchanger 2 and the second heat exchanger 4 in the second heat exchanger 4, so as to heat the photovoltaic module 1.

[0050] In this embodiment of the application, when the temperature of the photovoltaic module 1 is lower than the first preset temperature, the first heat exchange fluid heats the second heat exchange fluid circulating through the first heat exchanger 2 and the second heat exchanger 4 in the second heat exchanger 4, so as to heat the photovoltaic module 1.

[0051] Therefore, the photovoltaic temperature control system that utilizes the waste heat of the combined cycle unit can enhance the photoelectric conversion efficiency by reasonably regulating the operating temperature of the photovoltaic module 1, avoid the hot spot effect caused by excessive local temperature difference, and improve the service life of the photovoltaic module 1.

[0052] Furthermore, the photovoltaic temperature control system utilizing the waste heat of the combined cycle unit recovers the low-temperature heat energy from the exhaust of the waste heat boiler unit 20, improves the thermal efficiency of the waste heat boiler unit 20, reduces the energy loss of the combined cycle unit, and thus improves the overall efficiency of the combined cycle unit.

[0053] In addition, the photovoltaic temperature control system that utilizes the waste heat of the combined cycle unit can achieve deep coupling between the photovoltaic module 1 and the combined cycle unit under various operating modes, effectively improving the inherent shortcomings of the two power generation technologies and greatly enhancing the comprehensive energy utilization efficiency of the distributed energy system.

[0054] Optionally, the temperature control assembly further includes a lithium bromide refrigeration unit 3;

[0055] The first input terminal of the lithium bromide chiller 3 is connected to the output terminal of the flue gas waste heat recovery heat exchanger 15, and the first output terminal of the lithium bromide chiller 3 is connected to the input terminal of the flue gas waste heat recovery heat exchanger 15; the second input terminal of the lithium bromide chiller 3 is connected to the output terminal of the first heat exchanger 2, and the second output terminal of the lithium bromide chiller 3 is connected to the input terminal of the first heat exchanger 2.

[0056] When the temperature of the photovoltaic module 1 is higher than the second preset temperature, the first heat exchange fluid is cooled down by the lithium bromide refrigeration unit 3, and then the second heat exchange fluid circulating through the first heat exchanger 2 and the lithium bromide refrigeration unit 3 is cooled down to cool the photovoltaic module 1; wherein, the second preset temperature is higher than the first preset temperature.

[0057] In the above embodiments, when the temperature of the photovoltaic module 1 is too high, the photovoltaic temperature regulation system and method utilizing the waste heat of the combined cycle unit can reasonably cool down the operating temperature of the photovoltaic module 1, preventing ice formation or snow accumulation on the surface of the photovoltaic module 1, enhancing the photoelectric conversion efficiency, and improving the service life of the photovoltaic module 1.

[0058] Optionally, the temperature control assembly further includes a heat storage device 5;

[0059] The output end of the heat storage device 5 is connected to the input end of the flue gas waste heat recovery heat exchanger 15.

[0060] The first heat exchange fluid circulates through the flue gas waste heat recovery heat exchanger 15 and the heat storage device 5 to store heat in the heat storage device 5.

[0061] In the above embodiments, the low-temperature heat energy of the exhaust gas of the waste heat boiler unit 20 is effectively recovered, the thermal efficiency of the waste heat boiler unit 20 is improved, and it helps to achieve deep coupling between the photovoltaic module 1 and the combined cycle unit in various operating modes.

[0062] Optionally, the combined cycle unit further includes a gas turbine unit, a waste heat boiler unit 20, and a steam turbine unit; wherein the waste heat boiler unit 20 is connected to the flue gas waste heat recovery heat exchanger 15;

[0063] The gas turbine unit is connected to the waste heat boiler unit 20; the waste heat boiler unit 20 is connected to the steam turbine unit.

[0064] The gas turbine unit uses natural gas to generate high-temperature and high-pressure gas for power generation. After completing its work, the gas enters the waste heat boiler unit 20 and exchanges heat with water in stages to generate high-temperature and high-pressure steam of different levels. The waste heat recovery heat exchanger 15 recovers the heat from the flue gas in the waste heat boiler unit 20.

[0065] The steam turbine unit uses high-temperature and high-pressure steam of different grades generated by the waste heat boiler unit 20 to generate electricity.

[0066] In the above embodiments, the design of the combined cycle unit is relatively reasonable, which helps to make full and effective use of the waste heat of the combined cycle unit.

[0067] Optionally, the gas turbine unit includes a compressor 16, a combustion chamber 17, a turbine 18, and a first generator 19;

[0068] After being compressed by the compressor 16 in the gas turbine unit, the air enters the combustion chamber 17 and is mixed with natural gas to form high-temperature and high-pressure gas, which drives the turbine 18 to do work and drive the first generator 19 to generate electricity.

[0069] In the above embodiment, the gas turbine unit helps to generate high-temperature and high-pressure gas for use by the waste heat boiler unit 20, and also helps the first generator 19 to generate electricity.

[0070] Optionally, the steam turbine unit includes a high-pressure cylinder 21, an intermediate-pressure cylinder 22, a low-pressure cylinder 23, a second generator 24, a condenser 25, and a condensate pump 26;

[0071] The high-temperature and high-pressure steam of different grades generated by the waste heat boiler unit 20 enters the high-pressure cylinder 21, the medium-pressure cylinder 22 and the low-pressure cylinder 23 in sequence to do work and drive the second generator 24 to generate electricity; the exhaust steam after doing work enters the condenser 25 to condense into water, and is transported to the waste heat boiler unit 20 for recycling by the condensate pump 26.

[0072] In the above embodiments, it is helpful for the waste heat boiler unit 20 to make full use of the high temperature and high pressure gas generated by the gas turbine unit.

[0073] Optionally, see Figure 2 The second heat exchanger 4 and the lithium bromide refrigeration unit 3 are respectively connected to the heat storage device 5;

[0074] The heat stored in the heat storage device 5 can heat the second heat exchange fluid that circulates through the first heat exchanger 2 and the second heat exchanger 4 in the second heat exchanger 4, so as to heat the photovoltaic module 1.

[0075] The heat stored in the heat storage device 5 can also be cooled in the lithium bromide refrigeration unit 3 to cool the second heat exchange fluid that circulates through the first heat exchanger 2 and the lithium bromide refrigeration unit 3, thereby cooling the photovoltaic module 1.

[0076] In the above embodiments, the heat from the flue gas of the waste heat boiler unit 20 can be used to heat the photovoltaic module 1 as needed, and it also helps to cool down the photovoltaic module 1, making it very convenient to use.

[0077] According to a second aspect of the present invention, a photovoltaic temperature control method utilizing waste heat from a combined cycle unit is provided, applied to a photovoltaic temperature control system utilizing waste heat from a combined cycle unit as described in the first aspect, comprising the following steps:

[0078] The heat energy of the flue gas is recovered through the first heat exchange fluid;

[0079] When the temperature of the photovoltaic module 1 is lower than the first preset temperature, the first heat exchange fluid that recovers the heat energy of the flue gas heats the second heat exchange fluid that circulates through the first heat exchanger 2 and the second heat exchanger 4 in the second heat exchanger 4 to heat the photovoltaic module 1.

[0080] When the temperature of the photovoltaic module 1 is higher than the second preset temperature, the first heat exchange fluid that recovers the heat energy of the flue gas is cooled down by the lithium bromide refrigeration unit 3, and then the second heat exchange fluid that circulates through the first heat exchanger 2 and the lithium bromide refrigeration unit 3 is cooled down, so as to cool down the photovoltaic module 1; wherein, the second preset temperature is higher than the first preset temperature.

[0081] In the above embodiments, the photovoltaic temperature regulation method utilizing the waste heat of the combined cycle unit can enhance the photoelectric conversion efficiency by reasonably regulating the operating temperature of the photovoltaic module 1, avoid the hot spot effect caused by excessive local temperature difference, and improve the service life of the photovoltaic module 1.

[0082] Optionally, the first heat exchange fluid that recovers the heat energy from the flue gas circulates through the heat storage device 5 to store the heat in the heat storage device 5.

[0083] In the above embodiments, the low-temperature heat energy of the exhaust gas of the waste heat boiler unit 20 is effectively recovered, the thermal efficiency of the waste heat boiler unit 20 is improved, and it helps to achieve deep coupling between the photovoltaic module 1 and the combined cycle unit in various operating modes.

[0084] Optionally, see Figure 2 When the temperature of the photovoltaic module 1 is lower than the first preset temperature, the heat stored in the heat storage device 5 heats the second heat exchange fluid circulating through the first heat exchanger 2 and the second heat exchanger 4 in the second heat exchanger 4, so as to heat the photovoltaic module 1.

[0085] When the temperature of the photovoltaic module 1 is higher than the second preset temperature, the heat stored in the heat storage device 5 is cooled down in the lithium bromide refrigeration unit 3 and then used to cool down the second heat exchange fluid that circulates through the first heat exchanger 2 and the lithium bromide refrigeration unit 3, so as to cool down the photovoltaic module 1.

[0086] When the combined cycle unit is shut down, it can also heat or cool down the photovoltaic module 1, thereby enabling reasonable control of the operating temperature of the photovoltaic module 1, enhancing the photoelectric conversion efficiency, avoiding hot spot effect caused by excessive local temperature difference, and preventing surface icing or snow accumulation, thus improving the service life of the photovoltaic module 1.

[0087] It should be noted that the basic principle of the photovoltaic temperature control system and method utilizing waste heat from combined cycle units provided in this application embodiment is as follows:

[0088] When photovoltaic module 1 and the combined cycle unit are operating simultaneously, if photovoltaic module 1 needs cooling, the first heat exchange fluid first absorbs exhaust heat energy and heats up in the flue gas waste heat recovery heat exchanger 15. Then, the first heat exchange fluid enters the lithium bromide chiller 3 to cool the second heat exchange fluid. Finally, the second heat exchange fluid passes through the first heat exchanger 2 to cool photovoltaic module 1. If photovoltaic module 1 needs heating, the first heat exchange fluid first absorbs exhaust heat energy and heats up in the flue gas waste heat recovery heat exchanger 15. Then, the first heat exchange fluid enters the second heat exchanger 4 to heat the second heat exchange fluid. Finally, the second heat exchange fluid passes through the first heat exchanger 2 to heat photovoltaic module 1. When photovoltaic module 1 and the combined cycle unit are operating during off-peak hours, the first heat exchange fluid first absorbs exhaust heat energy and heats up in the flue gas waste heat recovery heat exchanger 15. Then, the heat is stored in the heat storage device 5. Then, according to the temperature regulation requirements of photovoltaic module 1, the heat energy in the heat storage device 5 is used to directly heat photovoltaic module 1 or to first cool and then cool photovoltaic module 1. That is, after the first heat exchange fluid absorbs heat in the flue gas recovery heat exchanger, it can enter the heat storage device 5 to store heat, or it can enter the second heat exchanger 4 to exchange heat with the second heat exchange fluid, or it can enter the lithium bromide refrigeration unit 3 to cool the second heat exchange fluid. The second heat exchange fluid exchanges heat with the photovoltaic module 1 through the first heat exchanger 2, thereby achieving the purpose of temperature regulation of the photovoltaic module 1.

[0089] In one implementation, see Figure 1 A first circulation branch is formed between the first heat exchanger 2 and the second heat exchanger 4. A first circulation pump 6 and a second valve 8 are installed on this first circulation branch. The second valve 8 is located near the second input end of the second heat exchanger 4, and the first circulation pump 6 is located near the second output end of the second heat exchanger 4. A second circulation branch is formed between the first heat exchanger 2 and the lithium bromide refrigeration unit 3. The first circulation pump 6 is located on this second circulation branch, and a first valve 7 is installed on this second circulation branch, located near the second input end of the lithium bromide refrigeration unit 3. A third circulation branch is formed between the flue gas waste heat recovery heat exchanger 15 and the heat storage device 5. A third valve 9, a sixth valve 12, and a third circulation pump 14 are all located on this third circulation branch. The third valve 9 is located near the output end of the heat storage device 5, the sixth valve 12 is located near the input end of the heat storage device 5, and the third circulation pump 14 is located near the output end of the flue gas waste heat recovery heat exchanger 15. A fourth circulation branch is formed between the flue gas waste heat recovery heat exchanger 15 and the second heat exchanger 4. The third circulation pump 14 and the third valve 9 are both located in the third circulation branch and the fourth circulation branch. The fifth valve 11 is located in the fourth circulation branch and is close to the first input end of the second heat exchanger 4. A fifth circulation branch is formed between the flue gas waste heat recovery heat exchanger 15 and the lithium bromide refrigeration unit 3. The third circulation pump 14 and the third valve 9 are both located in the fifth circulation branch. The fourth valve 10 is located in the fifth circulation branch and is close to the first input end of the lithium bromide refrigeration unit 3.

[0090] In another implementation, see Figure 2A sixth circulation branch is formed between the second heat exchanger 4 and the heat storage device 5, and the second circulation pump 13 is located in the sixth circulation branch. A seventh circulation branch is formed between the lithium bromide refrigeration unit 3 and the heat storage device 5, and the second circulation pump 13 is located in the seventh circulation branch.

[0091] In this embodiment, the photovoltaic temperature control system and method utilizing waste heat from a combined cycle unit has the following five operating modes:

[0092] See Figure 1 The first operating mode is photovoltaic module 1 operation + combined cycle unit operation + photovoltaic module 1 cooling.

[0093] That is, firstly, open the first valve 7, the third valve 9, and the fourth valve 10, close the second valve 8, the fifth valve 11, and the sixth valve 12, and start the first circulation pump 6 and the third circulation pump 14. The first heat exchange fluid first absorbs heat from the flue gas in the flue gas waste heat recovery heat exchanger 15 to raise its temperature, and then is transported to the lithium bromide refrigeration unit 3 via the third circulation pump 14 to cool the second heat exchange fluid. After that, it returns to the flue gas waste heat recovery heat exchanger 15 via the third valve 9 to continue heating. The second heat exchange fluid is cooled down by the lithium bromide refrigeration unit 3 and then transported by the first circulation pump 6 to the first heat exchanger 2 to cool the photovoltaic module 1. After absorbing heat and raising its temperature, it enters the lithium bromide refrigeration unit 3 via the first valve 7 to continue cooling.

[0094] See Figure 1 The second operating mode is photovoltaic module operation + combined cycle unit operation + photovoltaic module heating.

[0095] That is, firstly, open the second valve 8, the third valve 9, and the fifth valve 11, close the first valve 7, the fourth valve 10, and the sixth valve 12, and start the first circulation pump 6 and the third circulation pump 14. The first heat exchange fluid first absorbs heat from the flue gas in the flue gas waste heat recovery heat exchanger 15 to raise its temperature, and then is transported to the second heat exchanger 4 by the third circulation pump 14 to heat the second heat exchange fluid. After that, it returns to the flue gas waste heat recovery heat exchanger 15 through the third valve 9 to continue heating. After the second heat exchange fluid is heated by the second heat exchanger 4, it is transported to the first heat exchanger 2 by the first circulation pump 6 to heat the photovoltaic module 1. After releasing heat and cooling down, it enters the second heat exchanger 4 through the first valve 7 to continue heating.

[0096] See Figure 1 The third operating mode is photovoltaic module shutdown + combined cycle unit operation.

[0097] That is, first open the third valve 9 and the sixth valve 12, close the first valve 7, the second valve 8, the fourth valve 10 and the fifth valve 11, start the third circulation pump 14 and shut down the first circulation pump 6. The first heat exchange fluid first absorbs heat from the flue gas in the flue gas waste heat recovery heat exchanger 15 and is heated up. Then it is transported to the heat storage device 5 by the third circulation pump 14. The first heat exchange fluid releases heat in the heat storage device and stores the heat in the heat storage material. After that, it returns to the flue gas waste heat recovery heat exchanger 15 through the third valve 9 to continue heating.

[0098] See Figure 2 The fourth operating mode is photovoltaic module operation + combined cycle unit shutdown + photovoltaic module cooling.

[0099] That is, firstly, open the first valve 7, the fourth valve 10, and the sixth valve 12, close the second valve 8, the third valve 9, and the fifth valve 11, start the first circulation pump 6 and the second circulation pump 13, and shut down the third circulation pump 14. The first heat exchange fluid first absorbs heat from the heat storage material in the heat storage device 5 and is heated up. Then, it is transported to the lithium bromide refrigerator unit 3 via the second circulation pump 13 to cool the second heat exchange fluid. After that, it returns to the heat storage device 5 to continue heating. After being cooled down by the lithium bromide refrigerator unit 3, the second heat exchange fluid is transported to the first heat exchanger 2 by the first circulation pump 6 to cool the photovoltaic module 1. After absorbing heat and being heated up, it enters the lithium bromide refrigerator unit 3 via the first valve 7 for further cooling.

[0100] See Figure 2 The fifth operating mode is photovoltaic module operation + combined cycle unit shutdown + photovoltaic module heating.

[0101] That is, firstly, open the second valve 8, the fifth valve 11, and the sixth valve 12, close the first valve 7, the third valve 9, and the fourth valve 10, start the first circulation pump 6 and the second circulation pump 13, and shut down the third circulation pump 14. The first heat exchange fluid first absorbs heat from the flue gas in the heat storage device 5 and is heated up. The second circulation pump 13 delivers it to the second heat exchanger 4 to heat the second heat exchange fluid, and then returns to the heat storage device 5 for further heating. After the second heat exchange fluid is heated up in the second heat exchanger 4, it is delivered by the first circulation pump 6 to the first heat exchanger 2 to heat the photovoltaic module 1. After releasing heat and cooling down, it enters the second heat exchanger 4 through the first valve 7 for further heating.

[0102] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A photovoltaic temperature control system utilizing waste heat from a combined cycle power unit, characterized in that, include: A combined cycle unit, the combined cycle unit including a flue gas waste heat recovery heat exchanger, the flue gas waste heat recovery heat exchanger being used to recover flue gas heat energy through a first heat exchange fluid; The photovoltaic module and the temperature control module are provided. The temperature control module includes a first heat exchanger and a second heat exchanger. The first heat exchanger is connected to the photovoltaic module for heat exchange. The first input terminal of the second heat exchanger is connected to the output terminal of the flue gas waste heat recovery heat exchanger, and the first output terminal of the second heat exchanger is connected to the input terminal of the flue gas waste heat recovery heat exchanger. The second input terminal of the second heat exchanger is connected to the output terminal of the first heat exchanger, and the second output terminal of the second heat exchanger is connected to the input terminal of the first heat exchanger. When the temperature of the photovoltaic module is lower than the first preset temperature, the first heat exchange fluid heats the second heat exchange fluid circulating through the first and second heat exchangers in the second heat exchanger, so as to heat the photovoltaic module.

2. The photovoltaic temperature control system utilizing waste heat from a combined cycle unit according to claim 1, characterized in that, The temperature control component also includes a lithium bromide refrigeration unit; The first input terminal of the lithium bromide chiller is connected to the output terminal of the flue gas waste heat recovery heat exchanger, and the first output terminal of the lithium bromide chiller is connected to the input terminal of the flue gas waste heat recovery heat exchanger; the second input terminal of the lithium bromide chiller is connected to the output terminal of the first heat exchanger, and the second output terminal of the lithium bromide chiller is connected to the input terminal of the first heat exchanger. When the temperature of the photovoltaic module is higher than the second preset temperature, the first heat exchange fluid is cooled down by the lithium bromide refrigeration unit and then the second heat exchange fluid circulating through the first heat exchanger and the lithium bromide refrigeration unit is cooled down to cool the photovoltaic module; wherein, the second preset temperature is higher than the first preset temperature.

3. The photovoltaic temperature control system utilizing waste heat from a combined cycle unit according to claim 2, characterized in that, The temperature control component also includes a heat storage device; The output end of the heat storage device is connected to the input end of the flue gas waste heat recovery heat exchanger. The first heat exchange fluid circulates through the flue gas waste heat recovery heat exchanger and the heat storage device to store heat in the heat storage device.

4. The photovoltaic temperature control system utilizing waste heat from a combined cycle unit according to claim 3, characterized in that, The combined cycle unit also includes a gas turbine unit, a waste heat boiler unit, and a steam turbine unit; wherein the waste heat boiler unit is connected to the flue gas waste heat recovery heat exchanger. The gas turbine unit is connected to the waste heat boiler unit; the waste heat boiler unit is connected to the steam turbine unit. The gas turbine unit uses natural gas to generate high-temperature and high-pressure gas for power generation. After completing its work, the gas enters the waste heat boiler unit and exchanges heat with water in stages to generate high-temperature and high-pressure steam of different grades. The heat of the flue gas in the waste heat boiler unit is recovered through the flue gas waste heat recovery heat exchanger. The steam turbine unit uses high-temperature and high-pressure steam of different grades generated by the waste heat boiler unit to generate electricity.

5. The photovoltaic temperature control system utilizing waste heat from a combined cycle unit according to claim 4, characterized in that, The gas turbine unit includes a compressor, a combustion chamber, a turbine, and a first generator; Air is compressed by the compressor in the gas turbine unit and then enters the combustion chamber to mix with natural gas and burn to form high-temperature and high-pressure gas, which drives the turbine to do work and drive the first generator to generate electricity.

6. The photovoltaic temperature control system utilizing waste heat from a combined cycle unit according to claim 5, characterized in that, The steam turbine unit includes a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder, a second generator, a condenser, and a condensate pump; The high-temperature and high-pressure steam of different grades generated by the waste heat boiler unit enters the high-pressure cylinder, medium-pressure cylinder and low-pressure cylinder in sequence to do work and drive the second generator to generate electricity; the exhaust steam after doing work enters the condenser to condense into water, and is then transported to the waste heat boiler unit for recycling via the condensate pump.

7. The photovoltaic temperature control system utilizing waste heat from a combined cycle unit according to claim 6, characterized in that, The second heat exchanger and the lithium bromide refrigeration unit are respectively connected to the heat storage device; The heat stored in the heat storage device can heat the second heat exchange fluid that circulates through the first and second heat exchangers in the second heat exchanger, thereby heating the photovoltaic module. The heat stored in the heat storage device can also be cooled in the lithium bromide refrigeration unit to cool the second heat exchange fluid that circulates through the first heat exchanger and the lithium bromide refrigeration unit, thereby cooling the photovoltaic module.

8. A photovoltaic temperature regulation method utilizing waste heat from a combined cycle unit, characterized in that, The photovoltaic temperature control system for utilizing waste heat from a combined cycle unit as described in claim 7 includes the following steps: The heat energy of the flue gas is recovered through the first heat exchange fluid; When the temperature of the photovoltaic module is lower than the first preset temperature, the first heat exchange fluid that recovers the heat energy of the flue gas heats the second heat exchange fluid that circulates through the first heat exchanger and the second heat exchanger in the second heat exchanger, so as to heat the photovoltaic module. When the temperature of the photovoltaic module is higher than the second preset temperature, the first heat exchange fluid that recovers the heat energy of the flue gas is cooled down by the lithium bromide refrigeration unit and then used to cool down the second heat exchange fluid that circulates through the first heat exchanger and the lithium bromide refrigeration unit, so as to cool down the photovoltaic module; wherein, the second preset temperature is higher than the first preset temperature.

9. The photovoltaic temperature regulation method utilizing waste heat from a combined cycle unit according to claim 8, characterized in that, The first heat exchange fluid that recovers the heat energy from the flue gas circulates through the heat storage device to store the heat in the heat storage device.

10. The photovoltaic temperature regulation method utilizing waste heat from a combined cycle unit according to claim 9, characterized in that, When the temperature of the photovoltaic module is lower than the first preset temperature, the heat stored in the heat storage device heats the second heat exchange fluid circulating through the first heat exchanger and the second heat exchanger in the second heat exchanger, so as to heat the photovoltaic module. When the temperature of the photovoltaic module is higher than the second preset temperature, the heat stored in the heat storage device is cooled down in the lithium bromide refrigeration unit and then used to cool down the second heat exchange fluid that circulates through the first heat exchanger and the lithium bromide refrigeration unit, so as to cool down the photovoltaic module.

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