Energy conversion system

Abstract

The invention provides an energy conversion system which comprises a first pipeline which is communicated between a second medium outlet of a first heat exchange device and a fifth medium inlet of a second heat exchange device, so that first fluid flowing out of the second medium outlet of the first heat exchange device flows into the second heat exchange device; the second pipeline is communicated between the first medium outlet of the heat energy storage device and the second medium inlet of the first heat exchange device; and the third pipeline is communicated between the first medium outlet of the heat energy storage device and the fifth medium inlet of the second heat exchange device. According to the technical scheme, the problem that the heat energy utilization rate is low in the prior art is effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage, and in particular to an energy conversion system. Background Art

[0002] With the progress of society and the rapid development of science and technology, the rapid increase in total energy consumption has led to the excessive use of fossil fuels, and the large-scale combustion of fossil fuels will also produce a large amount of carbon dioxide. Therefore, in order to ensure that carbon peak and carbon neutrality can be successfully completed, efforts need to be made in multiple directions, among which changing the composition of energy is an important means. With the rapid increase in the installed capacity of renewable energy power generation such as wind power and solar power, the proportion of fossil energy in the power generation field is gradually decreasing, and the harmful substances after the combustion of fossil energy are also gradually decreasing. Renewable energy such as wind power and solar power will be affected by the weather. In the absence of wind and sun, the power generation system cannot generate electricity. The amount of electricity it generates has the disadvantages of randomness and uncontrollability, but power-consuming equipment will not stop using electricity due to weather conditions. Therefore, relevant renewable energy power plants must adopt practical technical means to improve the stability of unit power generation and meet the energy needs in larger energy-consuming areas.

[0003] As a method of storing electric energy from renewable energy power generation systems, energy storage technology has the advantages of improving energy utilization and absorption capacity, enhancing the stability and reliability of the power grid, and optimizing the economy of the power system. It can provide energy to surrounding energy-consuming areas with renewable energy power plants as the center. Energy storage technologies include thermal energy storage technology, mechanical energy storage technology, chemical energy storage technology, electrochemical energy storage technology, electrical energy storage technology, and hybrid energy storage technology. At the same time, in order to avoid the low economic benefits caused by the large initial investment and operating costs of the energy storage system, it is often necessary to consider the surrounding geographical and geological conditions to avoid excessive initial investment and low operating efficiency. At present, different energy storage systems are installed in combination with the surrounding conditions of the power plant to achieve electric energy storage and ensure the stability and reliability of the electric energy required by power-consuming equipment. For example, pumped energy storage and compressed air energy storage require corresponding geographical and geological conditions.

[0004] The above adjustment scheme has the following disadvantages:

[0005] 1. The energy storage technologies currently used in renewable energy power generation systems include thermal energy storage, mechanical energy storage, chemical energy storage, electrochemical energy storage, electrical energy storage and other energy storage technologies, among which pumped storage, compressed air storage and battery storage are more common. Pumped storage and compressed air storage have high site selection requirements, long construction periods and large investment amounts, and the flexibility of the energy storage system is very low.

[0006] 2. With the increase of installed capacity of renewable energy power generation, the volatility and flexibility of the power operation characteristics of renewable energy power generation systems need to be further improved. Under certain constraints, common energy storage technologies are difficult to match with power generation systems and cannot guarantee the power demand of power grids and users. Therefore, it is necessary to further improve the installation flexibility and system performance of energy storage technology, reduce system costs, and respond to the needs of renewable energy power generation systems and users.

[0007] Furthermore, when the cold water stored in the energy storage stage is completely used in the energy release stage, the hot water stored in the energy storage stage may not be completely used, that is, there may be a surplus of stored hot water, which results in the waste of stored thermal energy. Summary of the invention

[0008] The main purpose of the present invention is to provide an energy conversion system to solve the problem of low thermal energy utilization rate in the related art.

[0009] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, there is provided an energy conversion system, comprising: a first power generation device; an energy storage subsystem, the energy storage subsystem comprising a heat energy storage device for storing a first fluid and a cold energy storage device for storing a second fluid, the heat energy storage device having a first medium inlet and a first medium outlet; a conversion subsystem, the conversion subsystem comprising a first circulation loop, a compressor is provided on the first circulation loop, the first power generation device can drive the compressor to work, heat exchange can be performed between the first circulation loop and the heat energy storage device; an energy release subsystem, the energy release subsystem comprising a second circulation loop, heat exchange can be performed between the second circulation loop and the cold energy storage device, a first heat exchange device and an expansion device are provided on the second circulation loop, the first heat exchange device has a second medium inlet, a second medium outlet, a third medium inlet and a third medium outlet, the second medium inlet and the second medium outlet are connected, the third medium inlet and the third medium outlet are connected and are both located in the second circulation loop, the second medium inlet of the first heat exchange device is connected to the heat energy storage device The first medium outlet is connected to heat the third fluid in the second circulation loop through the first fluid, and the expansion device is connected to the third medium outlet; the second power generation device, the expansion device expands the third fluid in the second circulation loop so that the second power generation device generates electricity; the second heat exchange device, the second heat exchange device has a fourth medium inlet, a fourth medium outlet, a fifth medium inlet and a fifth medium outlet, the fourth medium inlet and the fourth medium outlet are connected, the fifth medium inlet and the fifth medium outlet are connected, and the fourth medium inlet and the fourth medium outlet are both connected to the consumption module; the first pipeline, the first pipeline is connected between the second medium outlet of the first heat exchange device and the fifth medium inlet of the second heat exchange device, so that the first fluid flowing out of the second medium outlet of the first heat exchange device flows into the second heat exchange device; the second pipeline, the second pipeline is connected between the first medium outlet of the thermal energy storage device and the second medium inlet of the first heat exchange device; the third pipeline, the third pipeline is connected between the first medium outlet of the thermal energy storage device and the fifth medium inlet of the second heat exchange device.

[0010] Furthermore, heat exchange is performed between the first circulation loop and the cold energy storage device, and the energy release subsystem also includes a third heat exchange device, which includes a sixth medium inlet, a sixth medium outlet, a seventh medium inlet and a seventh medium outlet, the sixth medium inlet and the sixth medium outlet are connected, the seventh medium inlet and the seventh medium outlet are connected, the sixth medium inlet is connected to the expansion device, the sixth medium outlet is connected to the third medium inlet of the first heat exchange device, and the seventh medium inlet is connected to the cold energy storage device, so that the second fluid flows into the third heat exchange device.

[0011] Furthermore, the energy release subsystem also includes a pressurizing device, which is arranged on the second circulation loop and is located between the sixth medium outlet of the third heat exchange device and the third medium inlet of the first heat exchange device.

[0012] Furthermore, the energy release subsystem also includes a first storage device, which is arranged on the second circulation loop and located between the sixth medium outlet of the third heat exchange device and the pressurizing device.

[0013] Furthermore, the energy storage subsystem also includes a second storage device, and the second storage device is connected to the seventh medium outlet of the third heat exchange device.

[0014] Further, the conversion subsystem includes a fourth heat exchange device and a fifth heat exchange device arranged on the first circulation loop, the fourth heat exchange device has an eighth medium inlet, an eighth medium outlet, a ninth medium inlet and a ninth medium outlet, the eighth medium inlet and the eighth medium outlet are connected, and the ninth medium inlet and the ninth medium outlet are connected, the fifth heat exchange device has a tenth medium inlet, a tenth medium outlet, an eleventh medium inlet and an eleventh medium outlet, the tenth medium inlet and the tenth medium outlet are connected, and the eleventh medium inlet and the eleventh medium outlet are connected, the second storage device is connected between the seventh medium outlet of the third heat exchange device and the ninth medium inlet of the fourth heat exchange device, the eighth medium outlet of the fourth heat exchange device is connected to the tenth medium inlet of the fifth heat exchange device, and the eleventh medium outlet of the fifth heat exchange device is connected to the thermal energy storage device to heat the first fluid flowing into the eleventh medium inlet.

[0015] Further, the fifth medium outlet of the second heat exchange device is communicated with the eleventh medium inlet of the fifth heat exchange device.

[0016] Furthermore, the eighth medium inlet of the fourth heat exchange device is connected to the tenth medium outlet of the fifth heat exchange device, and the ninth medium outlet of the fourth heat exchange device is connected to the cold energy storage device, so that the second fluid flows into the cold energy storage device.

[0017] Further, the compressor is arranged between the eighth medium outlet of the fourth heat exchange device and the tenth medium inlet of the fifth heat exchange device.

[0018] Furthermore, the conversion subsystem also includes an expansion valve, which is connected between the tenth medium outlet of the fifth heat exchange device and the eighth medium inlet of the fourth heat exchange device.

[0019] By applying the technical solution of the present invention, the first power generation device can drive the compressor to work. The energy storage subsystem includes a heat energy storage device and a cold energy storage device, and the cold energy storage device can store a second fluid. The heat energy storage device can store a first fluid, and the heat energy storage device has a first medium inlet and a first medium outlet. The first medium inlet can allow the first fluid to flow in, and the first medium outlet allows the first fluid to flow out. The conversion subsystem includes a first circulation loop, and the compressor is arranged on the first circulation loop, and the first circulation loop can exchange heat with the heat energy storage device. The energy release subsystem includes a second circulation loop, and the second circulation loop is provided with a first heat exchange device and an expansion device. The first heat exchange device has a second medium inlet, a second medium outlet connected to the second medium inlet, a third medium inlet, and a third medium outlet connected to the third medium inlet. The first fluid flowing out of the first medium outlet can flow into the first heat exchange device through the second medium inlet, and can heat the third fluid flowing in through the third medium inlet and flowing out through the third medium inlet to achieve heat exchange. The third fluid flowing out through the third medium inlet enters the expansion device and expands, thereby enabling the second power generation device to generate electricity. The second heat exchange device has a fourth medium inlet, a fourth medium outlet connected to the fourth medium inlet, a fifth medium inlet, and a fifth medium outlet connected to the fifth medium inlet. The first fluid flowing out of the second medium outlet can flow through the first pipeline and into the second heat exchange device through the fifth medium inlet, so that the second heat exchange device can exchange heat with the consumption module. The second pipeline allows the first fluid flowing out of the first medium outlet to flow to the second medium inlet, and then the first fluid can flow into the first heat exchange device. The third pipeline is connected between the first medium outlet of the thermal energy storage device and the fifth medium inlet of the second heat exchange device, so that when the second circulation loop is completed, the remaining first fluid in the thermal energy storage device can flow into the second heat exchange device through the fifth medium inlet, so that the second heat exchange device can exchange heat with the consumption module. Therefore, the technical solution of the present application effectively solves the problem of low thermal energy utilization in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1 A schematic diagram showing a principle of an embodiment of an energy conversion system according to the present invention is shown.

[0022] The above drawings include the following reference numerals:

[0023] 10. First power generation device; 20. Energy storage subsystem; 21. Heat energy storage device; 211. First medium inlet; 212. First medium outlet; 22. Cold energy storage device; 23. Second storage device; 30. Conversion subsystem; 31. Compressor; 32. Fourth heat exchange device; 321. Eighth medium inlet; 322. Eighth medium outlet; 323. Ninth medium inlet; 324. Ninth medium outlet; 33. Fifth heat exchange device; 331. Tenth medium inlet; 332. Tenth medium outlet; 333. Eleventh medium inlet; 334. Eleventh medium outlet; 34. Expansion valve; 35. Gas-liquid separation device; 36. Third storage device; 40. Energy release subsystem system; 41, first heat exchange device; 411, second medium inlet; 412, second medium outlet; 413, third medium inlet; 414, third medium outlet; 42, expansion device; 43, third heat exchange device; 431, sixth medium inlet; 432, sixth medium outlet; 433, seventh medium inlet; 434, seventh medium outlet; 44, pressurizing device; 45, first storage device; 50, second power generation device; 60, second heat exchange device; 61, fourth medium inlet; 62, fourth medium outlet; 63, fifth medium inlet; 64, fifth medium outlet; 70, first pipeline; 80, second pipeline; 90, third pipeline; 100, consumption module. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0026] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0027] like Figure 1As shown, the energy conversion system of this embodiment includes: a first power generation device 10, an energy storage subsystem 20, a conversion subsystem 30, an energy release subsystem 40, a second power generation device 50, a second heat exchange device 60, a first pipeline 70, a second pipeline 80 and a third pipeline 90. The energy storage subsystem 20 includes a heat storage device 21 for storing a first fluid and a cold storage device 22 for storing a second fluid, and the heat storage device 21 has a first medium inlet 211 and a first medium outlet 212. The conversion subsystem 30 includes a first circulation loop, and a compressor 31 is provided on the first circulation loop. The first power generation device 10 can drive the compressor 31 to work, and heat exchange can be performed between the first circulation loop and the heat storage device 21. The energy release subsystem 40 includes a second circulation loop, and heat exchange can be performed between the second circulation loop and the cold energy storage device 22. The second circulation loop is provided with a first heat exchange device 41 and an expansion device 42. The first heat exchange device 41 has a second medium inlet 411, a second medium outlet 412, a third medium inlet 413 and a third medium outlet 414. The second medium inlet 411 is connected to the second medium outlet 412, and the third medium inlet 413 is connected to the third medium outlet 414 and both are located in the second circulation loop. The second medium inlet 411 of the first heat exchange device 41 is connected to the first medium outlet 212 of the thermal energy storage device 21 to heat the third fluid in the second circulation loop through the first fluid, and the expansion device 42 is connected to the third medium outlet 414. The expansion device 42 expands the third fluid in the second circulation loop so that the second power generation device 50 generates electricity. The second heat exchange device 60 has a fourth medium inlet 61, a fourth medium outlet 62, a fifth medium inlet 63 and a fifth medium outlet 64. The fourth medium inlet 61 is connected to the fourth medium outlet 62, the fifth medium inlet 63 is connected to the fifth medium outlet 64, and the fourth medium inlet 61 and the fourth medium outlet 62 are both connected to the consumption module 100. The first pipeline 70 is connected between the second medium outlet 412 of the first heat exchange device 41 and the fifth medium inlet 63 of the second heat exchange device 60, so that the first fluid flowing out of the second medium outlet 412 of the first heat exchange device 41 flows into the second heat exchange device 60. The second pipeline 80 is connected between the first medium outlet 212 of the thermal energy storage device 21 and the second medium inlet 411 of the first heat exchange device 41. The third pipeline 90 is connected between the first medium outlet 212 of the thermal energy storage device 21 and the fifth medium inlet 63 of the second heat exchange device 60.

[0028] By applying the technical solution of this embodiment, the first power generation device 10 can drive the compressor 31 to work. The energy storage subsystem 20 includes a thermal energy storage device 21 and a cold energy storage device 22, and the cold energy storage device 22 can store a second fluid. The thermal energy storage device 21 can store a first fluid, and the thermal energy storage device 21 has a first medium inlet 211 and a first medium outlet 212. The first medium inlet 211 can allow the first fluid to flow in, and the first medium outlet 212 allows the first fluid to flow out. The conversion subsystem 30 includes a first circulation loop, and the compressor 31 is arranged on the first circulation loop, and the first circulation loop can exchange heat with the thermal energy storage device 21. The energy release subsystem 40 includes a second circulation loop, on which a first heat exchange device 41 and an expansion device 42 are arranged. The first heat exchange device 41 has a second medium inlet 411, a second medium outlet 412 connected to the second medium inlet 411, a third medium inlet 413, and a third medium outlet 414 connected to the third medium inlet 413. The first fluid flowing out through the first medium outlet 212 can flow into the first heat exchange device 41 through the second medium inlet 411, and can heat the third fluid flowing in through the third medium inlet 413 and flowing out through the third medium inlet 413 to achieve heat exchange. The third fluid flowing out through the third medium inlet 413 enters the expansion device 42 to expand, thereby enabling the second power generation device 50 to generate electricity. The second heat exchange device 60 has a fourth medium inlet 61, a fourth medium outlet 62 connected to the fourth medium inlet 61, a fifth medium inlet 63, and a fifth medium outlet 64 connected to the fifth medium inlet 63. The first fluid flowing out of the second medium outlet 412 can flow into the second heat exchange device 60 through the first pipeline 70 and the fifth medium inlet 63, so that the second heat exchange device 60 can exchange heat with the consumption module 100. The second pipeline 80 allows the first fluid flowing out of the first medium outlet 212 to flow to the second medium inlet 411, and then the first fluid can flow into the first heat exchange device 41. The third pipeline 90 is connected between the first medium outlet 212 of the thermal energy storage device 21 and the fifth medium inlet 63 of the second heat exchange device 60, so that when the second circulation loop is completed, the remaining first fluid in the thermal energy storage device 21 can flow into the second heat exchange device 60 through the fifth medium inlet 63, so that the second heat exchange device 60 can exchange heat with the consumption module 100. Therefore, the technical solution of this embodiment effectively solves the problem of low thermal energy utilization in the related art.

[0029] like Figure 1As shown, in this embodiment, heat exchange is performed between the first circulation loop and the cold energy storage device 22, and the energy release subsystem 40 further includes a third heat exchange device 43, which includes a sixth medium inlet 431, a sixth medium outlet 432, a seventh medium inlet 433 and a seventh medium outlet 434. The sixth medium inlet 431 is connected to the sixth medium outlet 432, the seventh medium inlet 433 is connected to the seventh medium outlet 434, the sixth medium inlet 431 is connected to the expansion device 42, the sixth medium outlet 432 is connected to the third medium inlet 413 of the first heat exchange device 41, and the seventh medium inlet 433 is connected to the cold energy storage device 22, so that the second fluid flows into the third heat exchange device 43. The third fluid can flow into the third heat exchange device 43 through the expansion device 42 and then through the sixth medium inlet 431. The second fluid flows out of the cold energy storage device 22 and then flows into the third heat exchange device 43 through the seventh medium inlet 433. In this way, the second fluid and the third fluid can exchange heat in the third heat exchange device 43, that is, the heat of the second fluid can be exchanged to the third fluid.

[0030] like Figure 1 As shown, in this embodiment, the energy release subsystem 40 further includes a pressurizing device 44, which is disposed on the second circulation loop and is located between the sixth medium outlet 432 of the third heat exchange device 43 and the third medium inlet 413 of the first heat exchange device 41. The pressurizing device 44 can pressurize the third fluid to facilitate the third fluid to work in the expansion device 42.

[0031] like Figure 1 As shown, in this embodiment, the energy release subsystem 40 further includes a first storage device 45, which is disposed on the second circulation loop and located between the sixth medium outlet 432 of the third heat exchange device 43 and the pressurizing device 44. The first storage device 45 can store a first fluid.

[0032] like Figure 1 As shown, in this embodiment, the energy storage subsystem 20 further includes a second storage device 23, and the second storage device 23 is connected to the seventh medium outlet 434 of the third heat exchange device 43. The second storage device 23 can store a second fluid.

[0033] like Figure 1As shown, in this embodiment, the conversion subsystem 30 includes a fourth heat exchange device 32 and a fifth heat exchange device 33 arranged on the first circulation loop, the fourth heat exchange device 32 has an eighth medium inlet 321, an eighth medium outlet 322, a ninth medium inlet 323 and a ninth medium outlet 324, the eighth medium inlet 321 is connected to the eighth medium outlet 322, the ninth medium inlet 323 is connected to the ninth medium outlet 324, the fifth heat exchange device 33 has a tenth medium inlet 331, a tenth medium outlet 332, an eleventh medium inlet and an eleventh medium outlet 33 4, the tenth medium inlet 331 is connected to the tenth medium outlet 332, the eleventh medium inlet 333 is connected to the eleventh medium outlet 334, the second storage device 23 is connected between the seventh medium outlet 434 of the third heat exchange device 43 and the ninth medium inlet 323 of the fourth heat exchange device 32, the eighth medium outlet 322 of the fourth heat exchange device 32 is connected to the tenth medium inlet 331 of the fifth heat exchange device 33, and the eleventh medium outlet 334 of the fifth heat exchange device 33 is connected to the thermal energy storage device 21, so as to heat the first fluid flowing into the eleventh medium inlet 333. The second fluid flowing out of the second storage device 23 can flow into the fourth heat exchange device 32 through the ninth medium inlet 323 and flow out through the ninth medium outlet 324 of the fourth heat exchange device 32, so that the second fluid can exchange heat with the fourth fluid in the fourth heat exchange device 32. The fourth fluid can flow in through the eighth medium inlet 321 , flow out through the eighth medium inlet 321 , and then flow into the fifth heat exchange device 33 through the tenth medium inlet 331 , so that the fourth fluid can exchange heat with the first fluid in the fifth heat exchange device 33 .

[0034] like Figure 1 As shown, in this embodiment, the fifth medium outlet 64 of the second heat exchange device 60 is communicated with the eleventh medium inlet 333 of the fifth heat exchange device 33. This allows the first fluid to flow into the fifth heat exchange device 33.

[0035] The first fluid flowing out of the first heat exchange device 41 flows into the second heat exchange device 60 and is stored. When the first circulation loop circulates, the first fluid in the second heat exchange device 60 flows out.

[0036] like Figure 1 As shown, in this embodiment, the eighth medium inlet 321 of the fourth heat exchange device 32 is connected to the tenth medium outlet 332 of the fifth heat exchange device 33, and the ninth medium outlet 324 of the fourth heat exchange device 32 is connected to the cold energy storage device 22, so that the second fluid flows into the cold energy storage device 22. The fourth fluid can flow to the eighth medium inlet 321 through the tenth medium outlet 332 and flow into the fourth heat exchange device 32. After the heat exchange of the fourth heat exchange device 32 is completed, the second fluid can flow into the cold energy storage device 22 through the ninth medium outlet 324.

[0037] like Figure 1 As shown, in this embodiment, the compressor 31 is disposed between the eighth medium outlet 322 of the fourth heat exchange device 32 and the tenth medium inlet 331 of the fifth heat exchange device 33. The compressor 31 can pressurize the fourth fluid flowing out of the eighth medium outlet 322, and the pressurized fourth fluid can flow into the fifth heat exchange device 33 through the tenth medium inlet 331.

[0038] like Figure 1 As shown, in this embodiment, the conversion subsystem 30 further includes an expansion valve 34, which is connected between the tenth medium outlet 332 of the fifth heat exchange device 33 and the eighth medium inlet 321 of the fourth heat exchange device 32. The expansion valve 34 can reduce the pressure of the fourth fluid.

[0039] The conversion subsystem 30 further includes a gas-liquid separation device 35, which is disposed between the compressor 31 and the fifth heat exchange device 33. The gas-liquid separation device 35 is in communication with the tenth medium inlet 331 of the fifth heat exchange device 33.

[0040] The conversion subsystem 30 further includes a third storage device 36, which is disposed between the expansion valve 34 and the fourth heat exchange device 32. The third storage device 36 is in communication with the tenth medium outlet 332 of the fifth heat exchange device 33.

[0041] The first power generation device 10 is a renewable energy power generation device. The heat energy storage device 21 is a first water storage tank. The cold energy storage device 22 is a second water storage tank. The compressor 31 is a carbon dioxide transcritical compressor 31. The first heat exchange device 41 is a first heat exchanger. The expansion device 42 is a carbon dioxide transcritical expander. The second power generation device 50 is a generator. The second heat exchange device 60 is a third water storage tank. The consumption module 100 is a building. The third heat exchange device 43 is a second heat exchanger. The pressurizing device 44 is a working fluid pump. The first storage device 45 is a first liquid storage tank. The second storage device 23 is a fourth water storage tank. The fourth heat exchange device 32 is a third heat exchanger. The fifth heat exchange device 33 is a fourth heat exchanger. The expansion valve 34 is an electronic expansion valve 34. The gas-liquid separation device 35 is a gas-liquid separator. The third storage device 36 is a second liquid storage tank.

[0042] The first fluid is water. The second fluid is water. The third fluid is carbon dioxide. The fourth fluid is carbon dioxide.

[0043] There is a fifth fluid in the consumption module 100. The fifth fluid is water.

[0044] The fifth fluid flows out of the consumption module 100, enters the second heat exchange device 60 through the fourth medium inlet, and exchanges heat with the first fluid flowing in through the fifth medium inlet to heat the fifth fluid, and then the fifth fluid flows back to the consumption module through the fourth medium outlet.

[0045] The fourth heat exchange device 32, the compressor 31, the gas-liquid separation device 35, the fifth heat exchange device 33, the expansion valve 34, and the third storage device 36 are all arranged on the first circulation loop.

[0046] The first storage device 45, the pressurizing device 44, the first heat exchange device 41, the expansion device 42, and the third heat exchange device 43 are all arranged on the second circulation loop.

[0047] This embodiment provides an energy conversion system, which is a carbon dioxide transcritical heat pump energy storage coupled building heating system. When the electric energy generated by the first power generation device 10 is greater than the power load, the electric energy can be converted into heat energy and cold energy through the carbon dioxide transcritical heat pump system cycle and stored in water. When the power load is greater than the power generation, the energy stored in the water drives the carbon dioxide transcritical power cycle, converts it into electric energy, and supplies it to power-consuming equipment. At the same time, by supplying the remaining heat energy in the energy release stage to the surrounding buildings, and by improving the utilization rate of the stored energy in the energy storage stage, it is possible to simultaneously meet the building's electric energy and heat energy needs.

[0048] The first circulation loop is a carbon dioxide transcritical heat pump system. The second circulation loop is a carbon dioxide transcritical heat engine system.

[0049] The energy conversion system of this embodiment mainly includes a carbon dioxide transcritical heat pump system, an energy storage coupled building heating system and a carbon dioxide transcritical heat engine system. Among them, the carbon dioxide transcritical heat pump system is composed of a third storage device 36, a fourth heat exchange device 32, a compressor 31, a first power generation device 10, a gas-liquid separation device 35, a fifth heat exchange device 33 and an expansion valve 34, the energy storage coupled building heating system is composed of a second storage device 23, a cold energy storage device 22, a second heat exchange device 60 and a heat energy storage device 21, and the carbon dioxide transcritical heat engine system is composed of a first storage device 45, a pressurizing device 44, a first heat exchange device 41, an expansion device 42, a second power generation device 50 and a third heat exchange device 43.

[0050] When the power generation of the first power generation device 10 is greater than the power load, the low-temperature and low-pressure carbon dioxide in the third storage device 36 enters the fourth heat exchange device 32 to absorb heat and become high-temperature and low-pressure carbon dioxide. At the same time, the normal temperature and normal pressure water in the second storage device 23 enters the fourth heat exchange device 32 to release heat and become low-temperature and normal pressure water. The low-temperature and normal pressure water flowing out of the fourth heat exchange device 32 enters the cold energy storage device 22 to complete the cold storage. The high-temperature and low-pressure carbon dioxide flowing out of the fourth heat exchange device 32 enters the compressor 31. The excess electricity generated by the first power generation device 10 drives the compressor 31 to compress the high-temperature and low-pressure carbon dioxide into high-temperature and high-pressure carbon dioxide. The high-temperature and high-pressure carbon dioxide flowing out of the compressor 31 enters the gas-liquid separation device 35 for Gas-liquid separation, the high-temperature and high-pressure carbon dioxide flowing out of the gas-liquid separation device 35 enters the fifth heat exchange device 33 to release heat and then becomes low-temperature and high-pressure carbon dioxide. At the same time, the normal-temperature and high-pressure water in the second heat exchange device 60 enters the fifth heat exchange device 33 to absorb heat and then becomes high-temperature and high-pressure water. The high-temperature and high-pressure water flowing out of the fifth heat exchange device 33 enters the thermal energy storage device 21 to complete heat storage. The low-temperature and high-pressure carbon dioxide flowing out of the fifth heat exchange device 33 enters the expansion valve 34 to throttle and reduce the pressure and then becomes low-temperature and low-pressure carbon dioxide. The low-temperature and low-pressure carbon dioxide flowing out of the expansion valve 34 enters the third storage device 36 to complete the carbon dioxide transcritical heat pump cycle, and the electrical energy generated by the first power generation device 10 is converted into heat energy and cold energy for storage respectively.

[0051] When the power generation of the first power generation device 10 is less than the power load, the low-temperature and low-pressure carbon dioxide flowing out of the first storage device 45 flows into the pressurizing device 44, and the low-temperature and low-pressure carbon dioxide is pressurized by the pressurizing device 44 to become low-temperature and high-pressure carbon dioxide. The low-temperature and high-pressure carbon dioxide flowing out of the pressurizing device 44 enters the first heat exchange device 41 to absorb heat and become high-temperature and high-pressure carbon dioxide. At the same time, the high-temperature and high-pressure water in the thermal energy storage device 21 enters the first heat exchange device 41 to release heat and become medium-temperature and high-pressure water. The medium-temperature and high-pressure water flowing out of the first heat exchange device 41 enters the second heat exchange device 60 to complete the heat release. The high-temperature and high-pressure carbon dioxide flowing out of the first heat exchange device 41 enters the expansion device 42, and the high-temperature and high-pressure carbon dioxide After entering the expansion device 42, it expands and does work and becomes high-temperature, low-pressure carbon dioxide. The expansion device 42 drives the second power generation device 50 to output electrical energy. The high-temperature, low-pressure carbon dioxide flowing out of the expansion device 42 enters the third heat exchange device 43 to release heat and becomes low-temperature, low-pressure carbon dioxide. At the same time, the low-temperature, normal-pressure water in the cold energy storage device 22 enters the third heat exchange device 43 to absorb heat and become normal-temperature, normal-pressure water. The normal-temperature, normal-pressure water flowing out of the third heat exchange device 43 enters the second storage device 23 to complete the release of cold energy. The low-temperature, low-pressure carbon dioxide flowing out of the third heat exchange device 43 enters the first storage device 45 to complete the carbon dioxide transcritical heat engine cycle, and the stored heat energy and cold energy are converted into electrical energy to supply corresponding power-consuming equipment.

[0052] After the carbon dioxide transcritical heat engine cycle is completed, the remaining high-temperature and high-pressure water in the thermal energy storage device 21 enters the second heat exchange device 60 and is mixed with the medium-temperature and high-pressure water flowing out of the first heat exchange device 41 in the second heat exchange device 60. The water in the second heat exchange device 60 becomes medium-temperature and high-pressure water, and the normal-temperature and normal-pressure water flowing out of the consumption module 100 enters the second heat exchange device 60 to absorb heat and become medium-temperature and normal-pressure water. At the same time, the medium-temperature and high-pressure water in the second heat exchange device 60 releases heat and becomes normal-temperature and high-pressure water. The medium-temperature and normal-pressure water flowing out of the second heat exchange device 60 enters the heating building to release heat, thereby realizing building heating.

[0053] After the second circulation loop is completed, at this time, the second fluid in the cold energy storage device 22 is used up, that is, there is no cold source in the carbon dioxide transcritical heat engine cycle. If there is still hot water in the thermal energy storage device 21, the third pipeline 90 is connected to directly connect the first medium outlet 212 of the thermal energy storage device 21 and the fifth medium inlet 63 of the second heat exchange device 60, so that the remaining high-temperature and high-pressure water in the thermal energy storage device 21 enters the second heat exchange device 60.

[0054] Whether the second fluid in the cold energy storage device 22 is used up can be measured by a liquid level gauge provided on the cold energy storage device 22, that is, whether the liquid level of water in the cold energy storage device 22 is lower than the height of the liquid level gauge.

[0055] The liquid level gauge may be installed at the very bottom of the cold energy storage device, or may be installed at a position close to the bottom of the cold energy storage device.

[0056] The energy conversion system also includes a controller, which is connected to the liquid level meter signal to receive a detection signal from the liquid level meter.

[0057] The energy conversion system also includes a display device, which is connected to the controller signal and can receive information from the controller. For example, after the detection signal of the liquid level meter is transmitted to the controller, the controller transmits it to the display device, and the liquid level height is displayed on the display device.

[0058] When the second circulation loop circulates, the second fluid enters the second storage device 23 for temporary storage after completing heat exchange in the third heat exchange device 43. When the first circulation loop circulates, the second fluid flows out of the second storage device and enters the fourth heat exchange device 32 for heat exchange.

[0059] When the second circulation loop circulates, after the first fluid completes heat exchange in the first heat exchange device 41, it enters the second heat exchange device 60 for temporary storage. When the first circulation loop circulates, the first fluid flows out of the second heat exchange device 60 and enters the fifth heat exchange device 33 for heat exchange.

[0060] When the first circulation loop circulates, the second fluid flows out of the second storage device and enters the fourth heat exchange device 32 for heat exchange, and then flows back to the cold energy storage device for temporary storage, and then flows out when the second circulation loop circulates.

[0061] When the first circulation loop circulates, the first fluid flows out of the second heat exchange device 60 and enters the fifth heat exchange device 33 for heat exchange, and then flows back to the thermal energy storage device for temporary storage, and then flows out when the second circulation loop circulates.

[0062] The first heat exchange device 41 includes a box body, in which a plurality of heat exchange channel groups are arranged in sequence at intervals in the direction from the first side of the box body to the second side of the box body, each heat exchange channel group includes a first channel and a second channel arranged along the direction from the first side of the box body to the second side of the box body, a first fluid flows through the first channel, a third fluid flows through the second channel, a plurality of first channels are connected to both the second medium inlet 411 and the second medium outlet 412, and a plurality of second channels are connected between the third medium inlet 413 and the third medium outlet 414.

[0063] The first heat exchange device 41 further includes a plurality of first heat exchange fins, and a first heat exchange fin is disposed between the first channel and the second channel.

[0064] The first heat exchange device 41 further includes a plurality of second heat exchange fins, and a second heat exchange fin is disposed between two adjacent heat exchange channel groups.

[0065] That is, a heat exchange channel group closest to the first side of the box has a first channel formed between the first heat exchange plate and the inner wall of the box, and a heat exchange channel group closest to the second side of the box has a second channel formed between the first heat exchange plate and the inner wall of the box.

[0066] Two adjacent heat exchange channel groups, the second channel of a heat exchange channel group close to the first side of the box body and the first channel of a heat exchange channel group far from the first side of the box body are separated by a second heat exchange fin.

[0067] The energy conversion system of this embodiment has the following advantages:

[0068] (1) After releasing heat in the thermal energy storage device 21, the water enters the second heat exchange device 60 and can exchange heat with the heat of the consumption module 100, thereby fully utilizing the heat stored in the energy storage stage, reducing heat loss and improving system energy utilization.

[0069] (2) The cold energy generated by the water in the cold energy storage device 22 during the energy storage stage is used to reduce the condensation temperature of the carbon dioxide transcritical heat engine cycle during the energy release stage, thereby improving the efficiency of the system.

[0070] (3) The energy conversion system of this embodiment can be coupled with energy storage subsystems of corresponding sizes for renewable energy power generation devices with different installed capacities, and has high flexibility and economy.

[0071] (4) The energy conversion system of this embodiment realizes the simultaneous storage of cold and heat in the energy storage stage. The stored cold can reduce the condensation temperature of the carbon dioxide transcritical heat engine cycle and improve the system efficiency.

[0072] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0073] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways, and the spatially relative descriptions used here are interpreted accordingly.

[0074] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0075] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An energy conversion system, characterized in that: include: A first power generation device (10); An energy storage subsystem (20), the energy storage subsystem (20) comprising a heat energy storage device (21) for storing a first fluid and a cold energy storage device (22) for storing a second fluid, the heat energy storage device (21) having a first medium inlet (211) and a first medium outlet (212); A conversion subsystem (30), the conversion subsystem (30) comprising a first circulation loop, a compressor (31) being arranged on the first circulation loop, the first power generation device (10) being capable of driving the compressor (31) to operate, and heat exchange being capable of being performed between the first circulation loop and the thermal energy storage device (21); An energy release subsystem (40), the energy release subsystem (40) comprising a second circulation loop, the second circulation loop and the cold energy storage device (22) being capable of heat exchange, the second circulation loop being provided with a first heat exchange device (41) and an expansion device (42), the first heat exchange device (41) having a second medium inlet (411), a second medium outlet (412), a third medium inlet (413) and a third medium outlet (414), the second medium inlet (411) being connected to the second medium outlet (412), the third medium inlet (413) being connected to the third medium outlet (414) and both being located in the second circulation loop, the second medium inlet (411) of the first heat exchange device (41) being connected to the first medium outlet (212) of the heat energy storage device (21) so as to heat the third fluid in the second circulation loop through the first fluid, the expansion device (42) being connected to the third medium outlet (414); a second power generation device (50), wherein the expansion device (42) causes the third fluid passing through the second circulation loop to expand so that the second power generation device (50) generates electricity; a second heat exchange device (60), the second heat exchange device (60) having a fourth medium inlet (61), a fourth medium outlet (62), a fifth medium inlet (63) and a fifth medium outlet (64), the fourth medium inlet (61) and the fourth medium outlet (62) being in communication, the fifth medium inlet (63) and the fifth medium outlet (64) being in communication, and the fourth medium inlet (61) and the fourth medium outlet (62) being in communication with the consumption module (100); a first pipeline (70), the first pipeline (70) being connected between the second medium outlet (412) of the first heat exchange device (41) and the fifth medium inlet (63) of the second heat exchange device (60), so that the first fluid flowing out of the second medium outlet (412) of the first heat exchange device (41) flows into the second heat exchange device (60); a second pipeline (80), the second pipeline (80) being connected between a first medium outlet (212) of the thermal energy storage device (21) and a second medium inlet (411) of the first heat exchange device (41); A third pipeline (90), the third pipeline (90) is connected between the first medium outlet (212) of the thermal energy storage device (21) and the fifth medium inlet (63) of the second heat exchange device (60).

2. The energy conversion system according to claim 1, characterized in that: Heat exchange is performed between the first circulation loop and the cold energy storage device (22). The energy release subsystem (40) further comprises a third heat exchange device (43). The third heat exchange device (43) comprises a sixth medium inlet (431), a sixth medium outlet (432), a seventh medium inlet (433) and a seventh medium outlet (434). The sixth medium inlet (431) is connected to the sixth medium outlet (432), the seventh medium inlet (433) is connected to the seventh medium outlet (434), the sixth medium inlet (431) is connected to the expansion device (42), the sixth medium outlet (432) is connected to the third medium inlet (413) of the first heat exchange device (41), and the seventh medium inlet (433) is connected to the cold energy storage device (22), so that the second fluid flows into the third heat exchange device (43).

3. The energy conversion system according to claim 2, characterized in that: The energy release subsystem (40) further comprises a pressurizing device (44), which is arranged on the second circulation loop and located between the sixth medium outlet (432) of the third heat exchange device (43) and the third medium inlet (413) of the first heat exchange device (41).

4. The energy conversion system according to claim 3, characterized in that: The energy release subsystem (40) further comprises a first storage device (45), wherein the first storage device (45) is arranged on the second circulation loop and is located between the sixth medium outlet (432) of the third heat exchange device (43) and the pressurizing device (44).

5. The energy conversion system according to claim 2, characterized in that: The energy storage subsystem (20) further comprises a second storage device (23), wherein the second storage device (23) is in communication with a seventh medium outlet (434) of the third heat exchange device (43).

6. The energy conversion system according to claim 5, characterized in that: The conversion subsystem (30) comprises a fourth heat exchange device (32) and a fifth heat exchange device (33) arranged on the first circulation loop, the fourth heat exchange device (32) having an eighth medium inlet (321), an eighth medium outlet (322), a ninth medium inlet (323) and a ninth medium outlet (324), the eighth medium inlet (321) and the eighth medium outlet (322) being in communication, the ninth medium inlet (323) and the ninth medium outlet (324) being in communication, the fifth heat exchange device (33) having a tenth medium inlet (331), a tenth medium outlet (332), an eleventh medium inlet (333) and an eleventh medium outlet (334), the tenth medium inlet (331) and the tenth medium outlet (332) being in communication with each other, The medium inlet (331) is connected to the tenth medium outlet (332), the eleventh medium inlet (333) is connected to the eleventh medium outlet (334), the second storage device (23) is connected between the seventh medium outlet (434) of the third heat exchange device (43) and the ninth medium inlet (323) of the fourth heat exchange device (32), the eighth medium outlet (322) of the fourth heat exchange device (32) is connected to the tenth medium inlet (331) of the fifth heat exchange device (33), and the eleventh medium outlet (334) of the fifth heat exchange device (33) is connected to the thermal energy storage device (21), so as to heat the first fluid flowing into the eleventh medium inlet (333).

7. The energy conversion system according to claim 6, characterized in that: The fifth medium outlet (64) of the second heat exchange device (60) is in communication with the eleventh medium inlet (333) of the fifth heat exchange device (33).

8. The energy conversion system according to claim 6 or 7, characterized in that: The eighth medium inlet (321) of the fourth heat exchange device (32) is connected to the tenth medium outlet (332) of the fifth heat exchange device (33), and the ninth medium outlet (324) of the fourth heat exchange device (32) is connected to the cold energy storage device (22), so that the second fluid flows into the cold energy storage device (22).

9. The energy conversion system according to claim 6 or 7, characterized in that: The compressor (31) is arranged between the eighth medium outlet (322) of the fourth heat exchange device (32) and the tenth medium inlet (331) of the fifth heat exchange device (33).

10. The energy conversion system according to claim 6 or 7, characterized in that: The conversion subsystem (30) further comprises an expansion valve (34), wherein the expansion valve (34) is connected between the tenth medium outlet (332) of the fifth heat exchange device (33) and the eighth medium inlet (321) of the fourth heat exchange device (32).

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