A distributed energy storage system and method coupled with a micro gas turbine

Abstract

The present invention belongs to the field of energy storage technologies and relates to a distributed energy storage system coupled with a micro gas turbine, comprising: a renewable energy power generation device; a micro gas turbine; a heat storage module for storing the heat in the air; a second turbine, the inlet of which is connected to the outlet of the heat storage module, and a first generator is connected to the output shaft of the second turbine; a cold storage module for storing the cold in the air; and an electric energy storage and utilization module for storing the electric energy generated by the first generator during the low electricity consumption period and delivering the electric energy generated by the first generator and the stored electric energy to the power grid during the high electricity consumption period. The present invention can store heat and cold while storing electric energy, not only realizes the efficient storage and utilization of the unstable electric energy generated by renewable energy power generation, avoids the power grid fluctuation problem caused by direct grid connection, but also provides reliable power, heat and cold supply for rural areas, and improves the utilization efficiency of renewable energy.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage, and relates to a distributed energy storage system and method coupled with a micro gas turbine. Background Art

[0002] The energy demand in rural areas is becoming increasingly diversified, covering various forms such as electricity and heat energy. Renewable energy sources, such as solar energy and wind energy, provide rich energy sources for rural areas. These energy sources are not only renewable but also widely distributed. Especially in rural areas, solar and wind energy resources are particularly abundant. By utilizing these renewable energy sources, rural areas can meet their own energy demands and reduce their dependence on external energy. However, with the large-scale application of renewable energy, the problems of intermittency and instability of energy have become increasingly prominent.

[0003] At present, in the aspect of energy storage for renewable energy power generation, an energy storage system coupled with a micro gas turbine is mostly adopted. The energy storage system coupled with a micro gas turbine smooths the fluctuations generated by the intermittency and instability of renewable energy on the power grid, thereby reducing the impact on the power grid.

[0004] However, since the energy storage system coupled with a micro gas turbine is mostly designed for single electric energy supply, lacking the consideration of multiple application scenarios and the ability of multi-energy co-production, its efficiency in storing and utilizing the unstable electric energy generated by renewable energy power generation is relatively low. This not only affects the utilization efficiency of renewable energy but also makes it difficult to provide other forms of energy for rural areas. Summary of the Invention

[0005] The purpose of the present invention is to provide a distributed energy storage system and method coupled with a micro gas turbine, which can store heat and cold while storing electric energy, not only realizing the efficient storage and utilization of the unstable electric energy generated by renewable energy power generation but also providing reliable power, heat, and cold supply for rural areas.

[0006] To achieve the above purpose, the technical solution provided by the present invention is as follows:

[0007] A distributed energy storage system coupled with a micro gas turbine, comprising:

[0008] Renewable energy power generation equipment for generating electricity using renewable energy.

[0009] A micro gas turbine, including a compressor, a first turbine, and a heating element. The inlet of the compressor is used to introduce normal temperature and pressure air. The outlet of the compressor is connected to the inlet of the heating element. The outlet of the heating element is connected to the inlet of the first turbine. The heating element is electrically connected to the renewable energy power generation equipment and is used to heat the compressed air.

[0010] A heat storage module, with its inlet connected to the outlet of the first turbine, is used to store the heat in the air.

[0011] A second turbine, with its inlet connected to the outlet of the heat storage module. The output shaft of the second turbine is connected to a first generator. The output shafts of the first turbine and the second turbine are coaxially connected to the drive shaft of the compressor.

[0012] A cold storage module, with its inlet connected to the outlet of the second turbine, is used to store the cold in the air.

[0013] An electric energy storage and utilization module is used to store the electric energy generated by the first generator during the low electricity consumption period and deliver the electric energy generated by the first generator and the stored electric energy to the power grid during the high electricity consumption period.

[0014] The features of the present invention also lie in:

[0015] Among them, the heat storage module includes:

[0016] A high-temperature heat exchanger, with its first inlet connected to the outlet of the first turbine. The first outlet of the high-temperature heat exchanger is connected to the inlet of the second turbine.

[0017] A heat storage tank, which stores a heat storage medium inside. The outlet of the heat storage tank is connected to the second inlet of the high-temperature heat exchanger, and the inlet of the heat storage tank is connected to the second outlet of the high-temperature heat exchanger.

[0018] Among them, the cold storage module includes:

[0019] A low-temperature heat exchanger, with its first inlet connected to the outlet of the second turbine. The first outlet of the low-temperature heat exchanger is connected to the atmosphere.

[0020] A cold storage tank, which stores a cold storage medium inside. The first outlet of the cold storage tank is connected to the second inlet of the low-temperature heat exchanger, and the first inlet of the cold storage tank is connected to the second outlet of the low-temperature heat exchanger.

[0021] Among them, the electric energy storage and utilization module includes:

[0022] At least one energy storage tank, which stores nitrogen inside.

[0023] A water storage tank, which stores water at normal temperature and pressure inside.

[0024] A first water pump, with its inlet connected to the first outlet of the water storage tank. The outlet of the first water pump is respectively connected to the first inlet and the second inlet of the energy storage tank. The first water pump is electrically connected to the first generator. The first water pump is used to pressurize the water at normal temperature and pressure in the water storage tank to become water at normal temperature and high pressure and deliver it into the energy storage tank.

[0025] An energy release component, which is connected to the energy storage tank and is used to convert the pressure energy in the stored water at normal temperature and high pressure into electric energy and deliver it to the power grid during the high electricity consumption period.

[0026] The energy release component includes:

[0027] A water turbine, whose inlet is connected to the outlet of the energy storage tank, the outlet of the water turbine is connected to the first inlet of the water storage tank, and the output end of the water turbine is connected with a second generator, and the electric energy generated by the second generator is transmitted to the power grid.

[0028] A preheater, which is connected to the renewable energy power generation equipment.

[0029] A second water pump, whose inlet is connected to the second outlet of the water storage tank, and the outlet of the second water pump is connected to the inlet of the preheater.

[0030] A heat exchanger, which is arranged on the energy storage tank and whose inlet is connected to the outlet of the preheater.

[0031] The outlet of the heat exchanger is connected to the second inlet of the cold storage tank, and the second outlet of the cold storage tank is connected to the second inlet of the water storage tank.

[0032] A distributed energy storage method coupled with a micro gas turbine includes the following steps:

[0033] Introduce normal temperature and pressure air into the compressor for pressurization, so that the normal temperature and pressure air becomes high temperature and high pressure air.

[0034] Introduce the high temperature and high pressure air into the heating element, and the electric energy generated by the renewable energy power generation equipment powers the heating element, and the heating element heats the high temperature and high pressure air, so that the high temperature and high pressure air becomes ultra-high temperature and high pressure air.

[0035] Introduce the ultra-high temperature and high pressure air into the first turbine for expansion work, the ultra-high temperature and high pressure air becomes high temperature and medium pressure air, and the heat in the high temperature and medium pressure air is stored in the heat storage module through the heat storage module, and the high temperature and medium pressure air becomes normal temperature and medium pressure air.

[0036] Introduce the normal temperature and medium pressure air into the second turbine for expansion work, the normal temperature and medium pressure air becomes low temperature and normal pressure air, and the cold in the low temperature and normal pressure air is stored in the cold storage module through the cold storage module, and the low temperature and normal pressure air becomes normal temperature and normal pressure air and is discharged.

[0037] During the low electricity consumption period, the electric energy generated by the first turbine and the second turbine driving the first generator is stored through the electric energy storage and utilization module. During the high electricity consumption period, the electric energy generated by the first turbine and the second turbine driving the first generator is directly transmitted to the power grid. At the same time, the electric energy stored in the electric energy storage and utilization module is transmitted to the power grid.

[0038] Among them, during the low electricity consumption period, the specific steps of storing the electric energy generated by the first turbine and the second turbine driving the first generator through the electric energy storage and utilization module are as follows:

[0039] The electric energy generated by driving the first generator with the first turbine and the second turbine is transmitted to the first water pump to start the first water pump. The first water pump pressurizes the normal temperature and pressure water in the water storage tank to become normal temperature and high pressure water. Part of the high temperature and high pressure water enters the water storage tank through the first inlet of the water storage tank for storage, and the other part of the high temperature and high pressure water enters the water storage tank through the second inlet of the water storage tank for spraying operation to cool the nitrogen, so that the nitrogen is isothermally compressed.

[0040] During the peak electricity consumption period, the specific steps for transmitting the electric energy stored in the electric energy storage and utilization module to the power grid are as follows:

[0041] The normal temperature and high pressure water in the energy storage tank is introduced into the water turbine. The electric energy generated by driving the second generator with the water turbine is transmitted to the power grid, and the normal temperature and high pressure water becomes normal temperature and pressure water and returns to the water storage tank.

[0042] Start the second water pump. The second water pump introduces the normal temperature water in the water storage tank into the preheater, and heats the normal temperature and pressure water through the low-grade heat generated by renewable energy, so that the normal temperature and pressure water becomes high temperature and pressure water. The high temperature and pressure water enters the heat exchanger to exchange heat with the nitrogen that expands and cools, so that the nitrogen keeps isothermal expansion, and the high temperature and pressure water becomes low temperature and pressure water.

[0043] The low temperature and pressure water is introduced into the heat storage tank. After storing the cold in the heat storage tank, it becomes normal temperature and pressure water and returns to the water storage tank.

[0044] Among them, the temperature of the normal temperature and pressure air is 15°C to 25°C, the pressure is 1 bar, the temperature of the high temperature and high pressure air is 150°C to 300°C, the pressure is 2 bar to 6 bar, the temperature of the ultra-high temperature and high pressure air is 650°C to 1200°C, the pressure is 2 bar to 6 bar, the temperature of the high temperature and medium pressure air is 150°C to 300°C, the pressure is 1.2 bar to 3 bar, the temperature of the normal temperature and medium pressure air is 25°C to 50°C, the pressure is 1.2 bar to 3 bar, the temperature of the low temperature and pressure air is -10°C to 15°C, the pressure is 1 bar, the temperature of the normal temperature and high pressure water is 20°C to 30°C, the pressure is 10 bar to 200 bar, the temperature of the high temperature and pressure water is 60°C to 90°C, the pressure is 1 bar, and the temperature of the low temperature and pressure water is 0°C to 15°C, the pressure is 1 bar.

[0045] A distributed energy storage system and method coupling a micro gas turbine of the present invention have the following advantages:

[0046] First, through the cooperation of the micro gas turbine, the second turbine, the heat storage module, the cold storage module and the electric energy storage and utilization module, it is possible to store heat and cold while storing electric energy, which not only realizes the efficient storage and utilization of the unstable electric energy generated by renewable energy power generation, avoids the power grid fluctuation problem caused by direct grid connection, but also provides reliable power, heat and cold supply for rural areas, improving the utilization efficiency of renewable energy.

[0047] Second, the present invention takes the micro gas turbine as the core, which is small in size, light in weight and compact in structure, making it particularly suitable for distributed deployment. The distributed design can fully adapt to the scenarios where the energy demands are scattered, such as rural areas and small factories. The system does not need to rely on large-scale centralized energy storage devices, nor does it require special terrain conditions. It can be independently deployed at multiple distributed nodes such as villages and factories, realizing flexible layout according to needs and quickly responding to local energy demands.

[0048] Third, the present invention can provide a stable energy input by combining the micro gas turbine with the unstable electric energy generated by renewable energy power generation, and uses the air in the external atmosphere as the working medium. Without high-pressure storage tanks or electrochemical energy storage devices, the distributed operation mode not only reduces the construction complexity and investment cost, but also enables each node to have the ability of independent operation. Even when the centralized power grid fails, it can maintain the reliable supply of local energy.

[0049] Fourth, the present invention adopts a modular design. Key devices such as energy storage tanks and heat exchangers are all of compact structure. The energy storage tanks can be flexibly arranged, supporting being buried underground or dispersed installation, greatly reducing the occupation of ground space, while improving the concealment and safety of the devices. The modular design also enables the system to flexibly expand the capacity according to actual needs and adapt to the energy demand fluctuations in different regions.

[0050] Fifth, through the distributed energy storage system, the present invention can flexibly adjust the energy release capacity during peak electricity consumption. By using the combined power generation of the micro gas turbine and the air turbine, and cooperating with the heat storage and cold storage devices, it realizes the comprehensive supply of electric energy, heat energy and cold energy. This distributed energy supply method is particularly suitable for the diversified energy demands of rural areas and small factories, providing reliable and efficient comprehensive energy solutions for users.

[0051] Sixth, the present invention can make full use of the characteristics of unstable electric energy in renewable energy (such as photovoltaic and wind power generation), convert it into stored heat energy, cold energy and potential energy, avoid the power grid fluctuation problem that may be caused by direct grid connection. At the same time, under the operation of distributed nodes, each micro gas turbine can independently cooperate with renewable energy to achieve efficient energy conversion and consumption, further optimizing the energy structure and increasing the proportion of clean energy in the system. Brief Description of the Drawings

[0052] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0053] Figure 2 This is a schematic diagram of the overall process structure of the present invention.

[0054] Figure 3 This is a schematic diagram of the energy release process structure of the present invention.

[0055] Reference numerals:

[0056] 1. Renewable energy power generation equipment, 2. Compressor, 3. Air heater, 4. First turbine, 5. High-temperature heat exchanger, 6. Heat storage tank, 7. Second turbine, 8. Low-temperature heat exchanger, 9. Cold storage tank, 10. First water pump, 11. Energy storage tank, 12. Heat exchanger, 13. Water turbine, 14. Water storage tank, 15. Second water pump, 16. Preheater, 17. Electric heater, 18. First control valve, 19. Second control valve, 20. Third control valve, 21. Fourth control valve, 22. Fifth control valve, 23. Sixth control valve, 24. Seventh control valve, 25. Eighth control valve, 26. Ninth control valve, 27. Tenth control valve, 28. First generator, 29. Second generator. Detailed implementation manners

[0057] Next, the technical solutions in the present application will be clearly and elaborately described in conjunction with the accompanying drawings. Among them, in the description of the embodiments of the present application, unless otherwise specified, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present application, "a plurality" means two or more than two. The following terms "first" and "second" are only used for descriptive purposes and cannot be construed as implying or indicating relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0058] As Figure 1As shown, the present invention provides a distributed energy storage system and method coupled with a micro gas turbine, comprising a micro gas turbine, a second turbine 7, a heat storage module, a cold storage module and an electric energy storage and utilization module, a renewable energy power generation device 1, which utilizes renewable energy to generate electricity, such as photovoltaic power generation, wind power generation, etc. The micro gas turbine comprises a compressor 2, a first turbine 4 and a heating element, the inlet of the compressor 2 is used to introduce air at normal temperature and pressure, and compress the air at normal temperature and pressure, the outlet of the compressor 2 is connected to the inlet of the heating element, the outlet of the heating element is connected to the inlet of the first turbine 4, the heating element is electrically connected to the renewable energy power generation device 1, the heating element is used to heat the compressed air, the inlet of the heat storage module is connected to the outlet of the first turbine 4, the heat storage module is used to store heat in the air, the inlet of the second turbine 7 is connected to the outlet of the heat storage module, the output shaft of the second turbine 7 is connected to the first generator 28, the output shaft of the first turbine 4, the output shaft of the second turbine 7, the drive shaft of the compressor 2 and the drive shaft of the first generator 28 are coaxially connected, In the initial stage, only a small amount of electric energy is needed to drive the compressor 2 to operate. After the entire system is running, the first turbine 4 and the second turbine 7 can drive the first motor to rotate and generate electricity during the rotation process, and drive the compressor 2 to rotate to provide kinetic energy for the operation of the compressor 2. The inlet of the cold storage module is connected to the outlet of the second turbine 7. The cold storage module is used to store the cold in the air, that is, the cold generated by the expansion work of the second turbine 7. The electric energy storage and utilization module is used to store the electric energy generated by the first generator 28 when the power consumption is low, and transmit the electric energy generated by the first generator 28 and the stored electric energy to the power grid when the power consumption is peak. Through the cooperation of the micro gas turbine, the second turbine 7, the heat storage module, the cold storage module and the electric energy storage and utilization module, heat and cold can be stored while storing electric energy, which not only realizes the efficient storage and utilization of the unstable electric energy generated by renewable energy power generation, avoids the power grid fluctuation problem caused by direct grid connection, but also provides reliable power, heat and cold supply for rural areas, and improves the utilization efficiency of renewable energy.

[0059] like Figure 1 As shown, based on the micro gas turbine, a compressor 2, a first turbine 4 and a heating element are used to replace the original micro gas turbine, so as to directly utilize the electric energy generated by the renewable energy power generation equipment 1 to replace the original combustible gas combustion, thereby avoiding the waste and pollution caused by the use of non-renewable energy.

[0060] like Figure 1As shown in the figure, the heating element consists of an air heater 3 and an electric heater 17. The inlet of the air heater 3 is connected to the outlet of the compressor 2, and the outlet of the air heater 3 is connected to the inlet of the first turbine 4. The electric heater 17 is electrically connected to the renewable energy power generation device 1, and the electric energy generated by the renewable energy power generation device 1 powers the electric heater 17. The heat generated by the operation of the electric heater 17 is supplied to the air heater 3 to heat the compressed air in the air heater 3.

[0061] As Figure 1 shown in the figure, the heat storage module includes a high-temperature heat exchanger 5 and a heat storage tank 6. The first inlet of the high-temperature heat exchanger 5 is connected to the outlet of the first turbine 4, the first outlet of the high-temperature heat exchanger 5 is connected to the inlet of the second turbine 7, the heat storage medium is stored inside the heat storage tank 6, the outlet of the heat storage tank 6 is connected to the second inlet of the high-temperature heat exchanger 5, and the inlet of the heat storage tank 6 is connected to the second outlet of the high-temperature heat exchanger 5.

[0062] As Figure 1 shown in the figure, the cold storage module includes a low-temperature heat exchanger 8 and a cold storage tank 9. The first inlet of the low-temperature heat exchanger 8 is connected to the outlet of the second turbine 7, the first outlet of the low-temperature heat exchanger 8 is connected to the atmosphere, which is convenient for discharging the normal-temperature and normal-pressure air into the atmosphere. The normal-temperature and normal-pressure air in the external atmosphere is used as the working medium, eliminating the need for high-pressure storage tanks or electrochemical energy storage devices. The cold storage medium is stored inside the cold storage tank 9, the first outlet of the cold storage tank 9 is connected to the second inlet of the low-temperature heat exchanger 8, and the first inlet of the cold storage tank 9 is connected to the second outlet of the low-temperature heat exchanger 8.

[0063] As Figure 1As shown in the figure, the electric energy storage and utilization module includes at least one energy storage tank 11, a water storage tank 14, a first water pump 10 and an energy release component. At least one energy storage tank 11 stores nitrogen gas inside. The number of energy storage tanks 11 can be arranged according to needs. The water storage tank 14 stores water at normal temperature and pressure. The inlet of the first water pump 10 is connected to the first outlet of the water storage tank 14. The outlet of the first water pump 10 is respectively connected to the first inlet and the second inlet of the energy storage tank 11. The first inlet is located at the lower part of the energy storage tank 11, and the second inlet is located at the upper part of the energy storage tank 11 and is provided with a spraying structure. The first water pump 10 is electrically connected to the first generator 28. The first water pump 10 is used to pressurize the water at normal temperature and pressure in the water storage tank 14 to become water at normal temperature and high pressure and transport it into the energy storage tank 11. A part of the water at normal temperature and high pressure directly enters the energy storage tank 11 for storage. During the storage process, the water at normal temperature and high pressure will compress the nitrogen gas. Another part of the water at normal temperature and high pressure is used to cool the nitrogen gas. This part of the water at normal temperature and high pressure enters the spraying structure through the second inlet and is sprayed into the energy storage tank 11 through the spraying structure to cool the compressed nitrogen gas inside. The energy release component is connected to the energy storage tank 11. The energy release component is used to convert the pressure energy in the stored water at normal temperature and high pressure into electric energy and transport it to the power grid during peak electricity consumption. The main purpose of setting nitrogen gas is to provide a buffering effect for the high-pressure water, mainly considering safety. Nitrogen gas has good compressibility and can play a buffering role when there are pressure fluctuations in the energy storage tank 11, reducing the system explosion risk and stress concentration. And directly storing water at normal temperature and high pressure will generate a large impact on the energy storage tank 11. The buffering effect of nitrogen gas can extend the service life of the energy storage tank 11.

[0064] As Figure 1 shown, the energy release component includes a water turbine 13, a preheater 16, a second water pump 15 and a heat exchanger 12. The inlet of the water turbine 13 is connected to the outlet of the energy storage tank 11. The outlet of the water turbine 13 is connected to the first inlet of the water storage tank 14. The output end of the water turbine 13 is connected to a second generator 29. The second generator 29 is driven to generate electricity by the rotation of the water turbine 13. The electric energy generated by the second generator 29 is transported to the power grid. The preheater 16 is connected to the renewable energy power generation device 1. The preheater 16 is used to receive the low-grade heat generated by the renewable energy power generation device 1. Low-grade heat refers to the heat energy generated during the energy conversion process, with relatively low quality or difficult to directly utilize. The inlet of the second water pump 15 is connected to the second outlet of the water storage tank 14. The outlet of the second water pump 15 is connected to the inlet of the preheater 16. The heat exchanger 12 is arranged on the energy storage tank 11. The inlet of the heat exchanger 12 is connected to the outlet of the preheater 16.

[0065] As Figure 1As shown in the figure, a first control valve 18 is provided at the inlet of the compressor 1, and the atmosphere is connected by opening and closing the first control valve 18. A second control valve 19 is provided at the outlet of the first water pump 10. A third control valve 20 is provided at the first inlet of the energy storage tank 11. A fourth control valve 21 is provided at the second inlet of the energy storage tank 11. The flow rates of the normal temperature and high-pressure water of the compressed nitrogen and the normal temperature and high-pressure water of the spray nitrogen are controlled by the third control valve 20 and the fourth control valve 21 respectively. Two outlets are provided on the energy storage tank 11, which are the first outlet and the second outlet respectively. A fifth control valve 22 is provided at the first outlet of the energy storage tank 11. A sixth control valve 23 is provided at the second outlet of the energy storage tank 11. The flow rate of water is controlled by the fifth control valve 22 and the sixth control valve 23. A seventh control valve 24 is provided at the inlet of the heat exchanger 12. The flow rate of the high-temperature and normal-pressure water entering the heat exchanger 12 is controlled by the seventh control valve 24. An eighth control valve 25 is provided at the second inlet of the water storage tank 14. A ninth control valve 26 is provided at the second outlet of the water storage tank 14. A tenth control valve 27 is provided at the inlet of the preheater 16.

[0066] As Figure 1 shown, the outlet of the heat exchanger 12 is connected to the second inlet of the cold storage tank 9, and the second outlet of the cold storage tank 9 is connected to the second inlet of the water storage tank 14.

[0067] As Figure 2 shown, the present invention also provides a distributed energy storage method coupled with a micro gas turbine, which includes the following steps:

[0068] Introduce normal temperature and normal pressure air into the compressor 2 for pressurization, so that the normal temperature and normal pressure air becomes high temperature and high pressure air.

[0069] Introduce the high temperature and high pressure air into the heating element, and the electric energy generated by the renewable energy power generation device 1 powers the heating element. The heating element heats the high temperature and high pressure air, so that the high temperature and high pressure air becomes ultra-high temperature and high pressure air.

[0070] Introduce the ultra-high temperature and high pressure air into the first turbine 4 for expansion work. The ultra-high temperature and high pressure air becomes high temperature and medium pressure air. The heat in the high temperature and medium pressure air is stored in the heat storage module through the heat storage module, and the high temperature and medium pressure air becomes normal temperature and medium pressure air.

[0071] Introduce the normal temperature and medium pressure air into the second turbine 7 for expansion work. The normal temperature and medium pressure air becomes low temperature and normal pressure air. The cold in the low temperature and normal pressure air is stored in the cold storage module through the cold storage module, and the low temperature and normal pressure air is discharged as normal temperature and normal pressure air.

[0072] During the low electricity consumption period, the electric energy generated by driving the first generator 28 by the first turbine 4 and the second turbine 7 is stored through the electric energy storage and utilization module. During the high electricity consumption period, the electric energy generated by driving the first generator 28 by the first turbine 4 and the second turbine 7 is directly transmitted to the power grid. At the same time, the electric energy stored in the electric energy storage and utilization module is transmitted to the power grid.

[0073] As Figure 2 shown, during the low electricity consumption period, the specific steps for storing the electric energy generated by driving the first generator 28 by the first turbine 4 and the second turbine 7 through the electric energy storage and utilization module are as follows:

[0074] Transmit the electric energy generated by driving the first generator 28 by the first turbine 4 and the second turbine 7 to the first water pump 10, start the first water pump 10, and the first water pump 10 pressurizes the normal temperature and normal pressure water in the water storage tank 14 to become normal temperature and high pressure water. Part of the high temperature and high pressure water enters the water storage tank 14 through the first inlet of the water storage tank 14 for storage, and the other part of the high temperature and high pressure water enters the water storage tank 14 through the second inlet of the water storage tank 14 for spraying operation to cool the nitrogen gas, so that the nitrogen gas is isothermally compressed.

[0075] As Figure 3 shown, during the high electricity consumption period, the specific steps for transmitting the electric energy stored in the electric energy storage and utilization module to the power grid are as follows:

[0076] Introduce the normal temperature and high pressure water in the energy storage tank 11 into the water turbine 13. The electric energy generated by driving the second generator 29 by the water turbine 13 is transmitted to the power grid, and the normal temperature and high pressure water becomes normal temperature and normal pressure water and returns to the water storage tank 14.

[0077] Start the second water pump 15. The second water pump 15 introduces the normal temperature water in the water storage tank 14 into the preheater 16, and heats the normal temperature and normal pressure water through the low-grade heat generated by the renewable energy power generation device 1, so that the normal temperature and normal pressure water becomes high temperature and normal pressure water. The high temperature and normal pressure water enters the heat exchanger 12 to exchange heat with the expanded and cooled nitrogen gas, so that the nitrogen gas maintains isothermal expansion, and the high temperature and normal pressure water becomes low temperature and normal pressure water.

[0078] Introduce the low temperature and normal pressure water into the heat storage tank 6, store the cold quantity in the heat storage tank 6, and then become normal temperature and normal pressure water and return to the water storage tank 14.

[0079] Among them, the temperature of normal temperature and pressure air is 15°C to 25°C, the pressure is 1 bar; the temperature of high temperature and pressure air is 150°C to 300°C, the pressure is 2 bar to 6 bar; the temperature of ultra-high temperature and pressure air is 650°C to 1200°C, the pressure is 2 bar to 6 bar; the temperature of high temperature and medium pressure air is 150°C to 300°C, the pressure is 1.2 bar to 3 bar; the temperature of normal temperature and medium pressure air is 25°C to 50°C, the pressure is 1.2 bar to 3 bar; the temperature of low temperature and pressure air is -10°C to 15°C, the pressure is 1 bar; the temperature of normal temperature and high pressure water is 20°C to 30°C, the pressure is 10 bar to 200 bar; the temperature of high temperature and pressure water is 60°C to 90°C, the pressure is 1 bar; the temperature of low temperature and pressure water is 0°C to 15°C, the pressure is 1 bar; the initial temperature of the heat storage medium is 50°C to 100°C, the highest temperature is 300°C to 500°C; the initial temperature of the cold storage medium is 5°C to 10°C, the lowest temperature is -5°C to -10°C.

[0080] Working principle: In the initial state, all the first control valve 18 to the tenth control valve 27 are closed, and the device is in a shutdown state.

[0081] When the user is in the low electricity consumption period, the fifth control valve 22, the sixth control valve 23, the seventh control valve 24, the eighth control valve 25, the ninth control valve 26, and the tenth control valve 27 are closed, and the first control valve 18, the second control valve 19, the third control valve 20, and the fourth control valve 21 are opened. The energy storage part starts to work. The normal temperature and pressure air in the atmosphere enters the compressor 2 for pressurization, so that the normal temperature and pressure air becomes high temperature and pressure air. The high temperature and pressure air enters the air heater 3. The electric energy generated by the renewable energy power generation device 1 powers the electric heater 17. The heat generated by the operation of the electric heater 17 is supplied to the air heater 3, so that the high temperature and pressure air becomes ultra-high temperature and pressure air. The ultra-high temperature and pressure air enters the first turbine 4 for power generation. The ultra-high temperature and pressure air becomes high temperature and medium pressure air. The high temperature and medium pressure air enters the high temperature heat exchanger 5 to exchange heat with the heat storage medium from the heat storage tank 6. The high temperature and medium pressure air becomes normal temperature and medium pressure air. The heat storage medium enters the heat storage tank 6 for storage, and is used for rural agriculture, rural factories and central heating. The normal temperature and medium pressure air enters the second turbine 7 for power generation. The normal temperature and medium pressure air becomes low temperature and pressure air. The low temperature and pressure air enters the low temperature heat exchanger 8 to exchange heat with the cold storage medium from the cold storage tank 9. The low temperature and pressure air becomes normal temperature and pressure air and is discharged. The cold storage medium returns to the cold storage tank 9 for storage and is used for the cold chain industry, etc.

[0082] The electric energy generated by driving the first generator 28 by the first turbine 4 and the second turbine 7 is transmitted to the first water pump 10 to start the first water pump 10. The first water pump 10 pressurizes the normal temperature and normal pressure water in the water storage tank 14 to become normal temperature and high pressure water and transmits it into the energy storage tank 11. A part of the normal temperature and high pressure water enters the energy storage tank 11 through the first inlet of the energy storage tank 11 for storage, and nitrogen is compressed during the storage process. Another part of the normal temperature and high pressure water enters the spraying structure through the second inlet of the energy storage tank 11, and high pressure water is sprayed into the energy storage tank 11 through the spraying structure for spraying operation to cool the compressed nitrogen so that the nitrogen can be isothermally compressed.

[0083] When the user is at the peak of power consumption, the second control valve 19 and the fourth control valve 21 are closed, and the first control valve 18, the fifth control valve 22, the sixth control valve 23, the seventh control valve 24, the eighth control valve 25, the ninth control valve 26, and the tenth control valve 27 are opened. The energy release part starts to work, and the compressor 2, the air heater 3, the electric heater 17, the first turbine 4, and the second turbine 7 continue to work, converting the unstable electric energy generated by the renewable energy power generation device 1 into stable electric energy and directly transmitting the stable electric energy to the power grid, and stopping power supply to the first water pump 10.

[0084] The first water pump 10 stops working, and the normal temperature and high pressure water in the energy storage tank 11 is introduced into the water turbine 13 to drive the water turbine 13 to generate electricity. The electric energy generated by driving the second generator 29 by the water turbine 13 is transmitted to the power grid. The normal temperature and high pressure water becomes normal temperature and normal pressure water and returns to the water storage tank 14. At the same time, the electric energy generated by the renewable energy power generation device 1 is used to supply power to the second water pump 15 to start the second water pump 15. The second water pump 15 introduces the normal temperature water in the water storage tank 14 into the preheater 16, and heats the normal temperature and normal pressure water through the low-grade heat generated by the renewable energy power generation device 1 so that the normal temperature and normal pressure water becomes high temperature and normal pressure water. The high temperature and normal pressure water enters the heat exchanger 12 to exchange heat with the nitrogen that expands and cools, so that the nitrogen maintains isothermal expansion. The high temperature and normal pressure water becomes low temperature and normal pressure water. The low temperature and normal pressure water is introduced into the heat storage tank 6, and the cold energy is stored in the heat storage tank 6 and then becomes normal temperature and normal pressure water and returns to the water storage tank 14 to complete the energy release process.

[0085] It can be understood that the present invention is described through some embodiments. Those skilled in the art know that without departing from the spirit and scope of the present invention, various changes or equivalent replacements can be made to these features and embodiments. In addition, under the teaching of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the scope protected by the present invention.

Claims

1. A distributed energy storage system coupled with a micro gas turbine, characterized in that, Comprising: Renewable energy power generation equipment (1) for generating electricity using renewable energy; A micro gas turbine including a compressor (2), a first turbine (4) and a heating element. The inlet of the compressor (2) is used to introduce ambient air at normal temperature and pressure. The outlet of the compressor (2) is connected to the inlet of the heating element. The outlet of the heating element is connected to the inlet of the first turbine (4). The heating element is electrically connected to the renewable energy power generation equipment (1) and is used to heat the compressed air; A heat storage module with an inlet connected to the outlet of the first turbine (4) for storing the heat in the air; A second turbine (7) with an inlet connected to the outlet of the heat storage module. The output shaft of the second turbine (7) is connected to a first generator (28). The output shafts of the first turbine (4) and the second turbine (7) and the drive shaft of the compressor (2) are coaxially connected; A cold storage module with an inlet connected to the outlet of the second turbine (7) for storing the cold in the air; An electric energy storage and utilization module for storing the electric energy generated by the first generator (28) during low electricity consumption periods and delivering the electric energy generated by the first generator (28) and the stored electric energy to the power grid during high electricity consumption periods; The electric energy storage and utilization module includes: At least one energy storage tank (11) storing nitrogen inside; A water storage tank (14) storing water at normal temperature and pressure inside; A first water pump (10) with an inlet connected to the first outlet of the water storage tank (14). The outlet of the first water pump (10) is respectively connected to the first inlet and the second inlet of the energy storage tank (11). The first water pump (10) is electrically connected to the first generator (28) and is used to pressurize the water at normal temperature and pressure in the water storage tank (14) to become water at normal temperature and high pressure and deliver it into the energy storage tank (11); An energy release component connected to the energy storage tank (11) for converting the pressure energy in the stored water at normal temperature and high pressure into electric energy and delivering it to the power grid during high electricity consumption periods; The energy release component includes: A water turbine (13) with an inlet connected to the outlet of the energy storage tank (11). The outlet of the water turbine (13) is connected to the first inlet of the water storage tank (14). The output end of the water turbine (13) is connected to a second generator (29). The electric energy generated by the second generator (29) is delivered to the power grid; A preheater (16) connected to the renewable energy power generation equipment (1); A second water pump (15) with an inlet connected to the second outlet of the water storage tank (14). The outlet of the second water pump (15) is connected to the inlet of the preheater (16); A heat exchanger (12) provided on the energy storage tank (11) with an inlet connected to the outlet of the preheater (16).

2. The distributed energy storage system coupled with a micro gas turbine according to claim 1, wherein, The heat storage module includes: A high-temperature heat exchanger (5) with a first inlet connected to the outlet of the first turbine (4). The first outlet of the high-temperature heat exchanger (5) is connected to the inlet of the second turbine (7); A heat storage tank (6) storing a heat storage medium inside. The outlet of the heat storage tank (6) is connected to the second inlet of the high-temperature heat exchanger (5). The inlet of the heat storage tank (6) is connected to the second outlet of the high-temperature heat exchanger (5).

3. A distributed energy storage system coupled with a micro gas turbine according to claim 2, characterized in that, The cold storage module includes: A low-temperature heat exchanger (8), the first inlet of which is connected to the outlet of the second turbine (7), and the first outlet of the low-temperature heat exchanger (8) is connected to the atmosphere; A cold storage tank (9) stores a cold storage medium inside. The first outlet of the cold storage tank (9) is connected to the second inlet of the low-temperature heat exchanger (8), and the first inlet of the cold storage tank (9) is connected to the second outlet of the low-temperature heat exchanger (8).

4. A distributed energy storage system coupled with a micro gas turbine according to claim 3, characterized in that The outlet of the heat exchanger (12) is connected to the second inlet of the cold storage tank (9), and the second outlet of the cold storage tank (9) is connected to the second inlet of the water storage tank (14).

5. A distributed energy storage method for coupling a micro gas turbine, characterized in that, Using a distributed energy storage system coupled with a micro gas turbine as described in claim 4, comprising the following steps: Introduce normal temperature and pressure air into the compressor (2) for pressurization, so that the normal temperature and pressure air becomes high temperature and high pressure air; Introduce the high temperature and high pressure air into a heating element. The electric energy generated by the renewable energy power generation device (1) powers the heating element, and the heating element heats the high temperature and high pressure air, so that the high temperature and high pressure air becomes ultra-high temperature and high pressure air; Introduce the ultra-high temperature and high pressure air into the first turbine (4) for expansion work. The ultra-high temperature and high pressure air becomes high temperature and medium pressure air. The heat in the high temperature and medium pressure air is stored in the heat storage module through the heat storage module, and the high temperature and medium pressure air becomes normal temperature and medium pressure air; Introduce the normal temperature and medium pressure air into the second turbine (7) for expansion work. The normal temperature and medium pressure air becomes low temperature and normal pressure air. The cold in the low temperature and normal pressure air is stored in the cold storage module through the cold storage module, and the low temperature and normal pressure air is discharged as normal temperature and normal pressure air; During the low electricity consumption period, the electric energy generated by the first turbine (4) and the second turbine (7) driving the first generator (28) is stored through the electric energy storage and utilization module. During the high electricity consumption period, the electric energy generated by the first turbine (4) and the second turbine (7) driving the first generator (28) is directly transmitted to the power grid. At the same time, the electric energy stored in the electric energy storage and utilization module is transmitted to the power grid; During the low electricity consumption period, the specific steps for storing the electric energy generated by the first turbine (4) and the second turbine (7) driving the first generator (28) through the electric energy storage and utilization module are as follows: Transmit the electric energy generated by the first turbine (4) and the second turbine (7) driving the first generator (28) to the first water pump (10). Start the first water pump (10). The first water pump (10) pressurizes the normal temperature and pressure water in the water storage tank (14) to become normal temperature and high pressure water. Part of the normal temperature and high pressure water enters the water storage tank (14) through the first inlet of the water storage tank (14) for storage, and the other part of the normal temperature and high pressure water enters the water storage tank (14) through the second inlet of the water storage tank (14) for spraying operation to cool the nitrogen, so that the nitrogen is isothermally compressed; During the high electricity consumption period, the specific steps for transmitting the electric energy stored in the electric energy storage and utilization module to the power grid are as follows: Introduce the normal temperature and high pressure water in the energy storage tank (11) into the water turbine (13). The electric energy generated by the water turbine (13) driving the second generator (29) is transmitted to the power grid, and the normal temperature and high pressure water becomes normal temperature and pressure water and returns to the water storage tank (14); Start the second water pump (15). The second water pump (15) introduces the normal temperature and pressure water in the water storage tank (14) into the preheater (16), heats the normal temperature and pressure water through the low-grade heat generated by the renewable energy power generation device (1), so that the normal temperature and pressure water becomes high-temperature and pressure water. The high-temperature and pressure water enters the heat exchanger (12) to exchange heat with the expanding and cooling nitrogen gas, so that the nitrogen gas keeps isothermal expansion, and the high-temperature and pressure water becomes low-temperature and pressure water; Introduce the low-temperature and pressure water into the cold storage tank (9). After storing the cold in the cold storage tank (9), it becomes normal temperature and pressure water and returns to the water storage tank (14).

6. A distributed energy storage method for coupling a micro gas turbine according to claim 5, characterized in that, The temperature of the normal temperature and pressure air is 15°C to 25°C, and the pressure is 1 bar; the temperature of the high-temperature and high-pressure air is 150°C to 300°C, and the pressure is 2 bar to 6 bar; the temperature of the ultra-high-temperature and high-pressure air is 650°C to 1200°C, and the pressure is 2 bar to 6 bar; the temperature of the high-temperature and medium-pressure air is 150°C to 300°C, and the pressure is 1.2 bar to 3 bar; the temperature of the normal temperature and medium-pressure air is 25°C to 50°C, and the pressure is 1.2 bar to 3 bar; the temperature of the low-temperature and pressure air is -10°C to 15°C, and the pressure is 1 bar; the temperature of the normal temperature and high-pressure water is 20°C to 30°C, and the pressure is 10 bar to 200 bar; the temperature of the high-temperature and pressure water is 60°C to 90°C, and the pressure is 1 bar; the temperature of the low-temperature and pressure water is 0°C to 15°C, and the pressure is 1 bar.

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