A compressed air energy storage system with integrated HVAC function and control method thereof

Abstract

The present invention provides a compressed air energy storage system with integrated HVAC functions and a control method thereof, wherein the system includes a first compressor, a second compressor, a third compressor, an air storage chamber, a first heat exchanger, a second heat exchanger, a third heat exchanger, a first air heater, a second air heater, a low-temperature storage tank, a high-temperature storage tank, a high-temperature delivery pump, a variable frequency pump, a low-temperature delivery pump, a first turbine, a second turbine and a generator, wherein the variable frequency pump is used to adjust the flow of the heat exchange medium entering the second air heater, change the compressed air inlet temperature of the second turbine, adjust the exhaust temperature of the second turbine to the required heating or cooling, and directly enter the heating or cooling space through the HVAC pipe network. The present invention utilizes the compressed air energy storage system to achieve peak power regulation, and at the same time, the turbine exhaust temperature can be controlled in real time through adjustment means, and the cold and hot air are directly delivered to the space that needs cooling or heating, thereby obtaining additional use value.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage, and in particular relates to a compressed air energy storage system with integrated HVAC functions and a control method thereof. Background Art

[0002] Energy storage technology is the key to building a new power system and promoting the green and low-carbon transformation of energy. Compressed air energy storage has the advantages of large scale, high efficiency, low cost and environmental protection, and is considered to be one of the most promising large-scale new energy storage technologies.

[0003] In addition to electricity demand, many existing compressed air energy storage planning projects also require cooling or heat supply at the user end. Directly using high-grade electricity for heating and cooling causes a certain degree of energy waste.

[0004] The use of compressed air energy storage systems to achieve combined heat, cooling and power generation can not only promote the consumption of renewable energy such as wind and solar power, but also greatly improve energy utilization efficiency through the complementary integration and cascade utilization of cold, heat, electricity and other energies. It is low-carbon and environmentally friendly, which is very in line with energy development needs. Summary of the invention

[0005] In view of the above problems, the present invention provides a compressed air energy storage system with integrated HVAC functions and a control method thereof, which greatly improves energy utilization efficiency and is low-carbon and environmentally friendly.

[0006] A compressed air energy storage system with integrated HVAC function, comprising a first compressor, a second compressor, a third compressor, an air storage chamber, a first heat exchanger, a second heat exchanger, a third heat exchanger, a first air heater, a second air heater, a low-temperature storage tank, a high-temperature storage tank, a high-temperature delivery pump, a variable frequency pump, a low-temperature delivery pump, a first turbine, a second turbine and a generator; wherein the inlet of the first compressor is connected to an air pipeline, the air side of the first heat exchanger is connected to the outlet of the first compressor and the inlet of the second compressor through a pipeline, and the air side of the second heat exchanger is connected to the outlet of the second compressor and the inlet of the third compressor through a pipeline. The air side of the third heat exchanger is connected to the outlet of the third compressor and the air inlet of the air storage chamber through a pipeline, the air outlet of the air storage chamber is connected to the first pipeline, the air side of the first air heater, the second pipeline and the inlet of the first turbine in sequence, the outlet of the first turbine is connected to the air side of the second air heater, the third pipeline and the inlet of the second turbine in sequence, the outlet of the second turbine is connected to the HVAC network, the first turbine and the second turbine are used to drive the generator to work; the outlet of the low-temperature storage tank is connected to the inlet of the low-temperature delivery pump, and the outlet of the low-temperature delivery pump is connected to the inlet of the low-temperature delivery pump. The first end of the heat exchange medium side of the high temperature storage tank is connected to the first end of the heat exchange medium side of the high temperature storage tank, and the second end of the heat exchange medium side of the high temperature storage tank is connected to the first end of the heat exchange medium side of the high temperature storage tank. The first end of the heat exchange medium side of the high temperature storage tank is connected to the first end of the heat exchange medium side of the high temperature delivery pump and the first end of the heat exchange medium side of the first air heater in sequence. The second end of the heat exchange medium side of the first air heater is connected to the first end of the fourth pipeline and the first end of the fifth pipeline respectively. The second end of the fourth pipeline is connected to the heat exchange medium side of the high temperature storage tank. The user and the inlet of the low-temperature storage tank are connected in sequence, and the second end of the fifth pipeline is connected in sequence with the inlet of the low-temperature storage tank; the second outlet of the high-temperature storage tank is connected in sequence with the variable frequency pump and the first end of the heat exchange medium side of the second air heater, and the second end of the heat exchange medium side of the second air heater is connected with the first end of the fourth pipeline and the first end of the fifth pipeline respectively; the variable frequency pump is used to adjust the flow rate of the heat exchange medium entering the second air heater, change the compressed air inlet temperature of the second turbine, adjust the exhaust temperature of the second turbine to the requirements of heating or cooling, and directly enter the heating or cooling space through the HVAC pipeline network.

[0007] Further, a cooling tower is also included;

[0008] Wherein, the cooling tower is arranged at the front end of the inlet of the low-temperature storage tank, and a bypass is provided in the cooling tower. The first end of the bypass is connected to the second end of the fifth pipeline and the heat user, and the second end of the bypass is connected to the inlet of the low-temperature storage tank. A temperature sensor is arranged in front of the first end of the bypass.

[0009] Furthermore, the first pipeline is provided with an air source auxiliary regulating valve or an air source auxiliary regulating valve group.

[0010] Furthermore, a first inlet regulating valve is provided on the second pipeline, and a second inlet regulating valve is provided on the third pipeline.

[0011] Furthermore, the fourth pipeline is provided with a first flow regulating valve, and the fifth pipeline is provided with a second flow regulating valve.

[0012] Furthermore, a silencer is provided between the outlet of the second turbine and the HVAC pipe network.

[0013] Further, a third air heater is included;

[0014] Among them, the two ends of the air side of the third air heater are respectively connected to the air side of the second air heater and the third pipeline, and the two ends of the heat exchange medium side of the third air heater are respectively connected to the variable frequency pump and the first end of the heat exchange medium side of the second air heater.

[0015] Furthermore, a first bypass valve is provided on the heat exchange medium side of the third air heater, and a second bypass valve is provided on the air side of the third air heater.

[0016] Furthermore, an air filter is provided on the air duct.

[0017] Furthermore, the gas storage chamber includes a plurality of independent chambers.

[0018] The present invention also provides a control method for the compressed air energy storage system with integrated HVAC function, comprising the following steps:

[0019] The first compressor, the second compressor and the third compressor are driven by an electric motor to compress the air;

[0020] The heat exchange medium is transported from the low-temperature storage tank to the heat exchange medium side of the first heat exchanger, the heat exchange medium side of the second heat exchanger, and the heat exchange medium side of the third heat exchanger through a low-temperature delivery pump to exchange heat with the high-temperature air at the outlets of the first compressor, the second compressor, and the third compressor, and the high-temperature heat exchange medium after heat exchange is transported to the high-temperature storage tank for storage, and the high-pressure air after heat exchange is stored in the air storage chamber;

[0021] When high-pressure air is delivered from the air storage chamber to the air side of the first air heater through the first pipeline, a heat exchange medium is delivered to the heat exchange medium side of the first air heater through a high-temperature delivery pump to heat the compressed air on the air side of the first pipeline, and the compressed air that has obtained the stored heat is input to the first turbine through the second pipeline to expand and perform work;

[0022] The heat exchange medium is transported to the heat exchange medium side of the second air heater through the variable frequency pump to heat the compressed air on the air side of the second air heater. The heated compressed gas enters the second turbine through the third pipeline and drives the generator to work through the first turbine and the second turbine.

[0023] The flow rate of heat exchange medium entering the second air heater is adjusted by the variable frequency pump, the compressed air inlet temperature of the second turbine is changed, the exhaust steam temperature of the second turbine is adjusted to the heating or cooling requirement, and directly enters the heating or cooling space through the HVAC pipe network;

[0024] The heat exchange medium flowing out of the heat exchange medium side of the first air heater and the heat exchange medium side of the second air heater is distributed through the fourth pipeline or the fifth pipeline to provide heat to heat users.

[0025] Further, adjusting the exhaust temperature of the second turbine to the required temperature for heating or cooling includes the following steps:

[0026] Preset the throttling degree for the first inlet regulating valve on the second pipeline and the second inlet regulating valve on the third pipeline, and when the exhaust temperature of the second turbine is higher than the first preset value, open the second inlet regulating valve, or open the first inlet regulating valve and the second inlet regulating valve;

[0027] When the exhaust temperature of the second turbine is lower than the second preset value, the second inlet regulating valve may be closed, or the first inlet regulating valve and the second inlet regulating valve may be closed.

[0028] Further, adjusting the exhaust temperature of the second turbine to a temperature required for heating or cooling also includes the following steps:

[0029] When the exhaust temperature of the second turbine is lower than the second preset value, the flow rate of the heat exchange medium is increased by the variable frequency pump, so that the temperature of the compressed air entering the second turbine is increased;

[0030] When the exhaust temperature of the second turbine is higher than the first preset value, the flow rate of the heat exchange medium is reduced by the variable frequency pump, so that the temperature of the compressed air entering the second turbine is reduced.

[0031] Beneficial effects of the present invention:

[0032] 1. The present invention utilizes the compressed air energy storage system to achieve peak power regulation. At the same time, the turbine exhaust temperature can be controlled in real time through adjustment means, and the cold and hot wind (air) are directly sent to the space that needs cooling or heating, thereby obtaining additional use value. At the same time, the real-time control of cold and heat is also achieved, and there is no need to set up a cold storage device or a heating hot water storage tank, so the system is simpler.

[0033] 2. Compared with the conventional cooling, heat and power combined compressed air energy storage system, the present invention directly supplies turbine exhaust gas to the space requiring cooling or heating, thereby reducing the heat exchange link, resulting in less power generation loss, saving investment costs, and reducing operation and maintenance costs.

[0034] 3. The present invention is suitable for comprehensive energy consumption areas such as urban transportation hubs. The cooling or heating period basically coincides with the turbine power generation period. There is no need to consume electricity or other energy for cooling and heating during peak hours, and the operating cost is low. In addition, the system has a large turbine exhaust volume, and the amount of fresh air delivered to the transportation hub is also large, which is a very healthy and environmentally friendly cooling and heating solution.

[0035] 4. The HVAC system of the present invention is applied to areas with high humidity, which will greatly improve the comfort level.

[0036] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 A schematic structural diagram of a first embodiment of a compressed air energy storage system with integrated HVAC functions according to the present invention is shown;

[0039] Figure 2 A schematic structural diagram of a second embodiment of a compressed air energy storage system with integrated HVAC functions according to the present invention is shown.

[0040] In the figure: 1. air filter; 2. electric motor; 3. first compressor; 4. first heat exchanger; 5. second compressor; 6. second heat exchanger; 7. third compressor; 8. third heat exchanger; 9. air storage chamber; 10. air source auxiliary regulating valve; 11. first air heater; 12. first turbine; 13. second air heater; 14. second turbine; 15. muffler; 16. generator; 17. high temperature storage tank; 18. high temperature delivery pump; 19. variable frequency pump; 20. first flow regulating valve; 21. second flow regulating valve; 22. cooling tower; 23. low temperature storage tank; 24. low temperature delivery pump; 25. HVAC pipe network; 26. first inlet regulating valve; 27. second inlet regulating valve; 28. first bypass valve; 29. ​​second bypass valve; 30. third air heater. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. 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.

[0042] It should be noted that the terms "first", "second" etc. in the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged in appropriate circumstances, so that the embodiments of the present application described here. In the present application, the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" etc. are based on the orientation or positional relationship shown in the accompanying drawings.

[0043] In order to facilitate the understanding of the embodiments of the present application, the compressed air energy storage technology is briefly introduced below.

[0044] Compressed air energy storage technology converts surplus electricity into pressure potential energy and heat of air and stores them separately. During peak electricity demand periods, the stored heat is returned to low-temperature and high-pressure air, and the high-temperature and high-pressure air drives the turbine to do work. In addition to electricity demand, the user end also needs cold or heat supply; the reasonable design of the compressed air energy storage system to achieve combined cooling, heating and power not only saves equipment investment, but also improves the comprehensive utilization efficiency of energy. It is an efficient energy utilization model worthy of promotion.

[0045] like Figure 1As shown, an embodiment of the present invention provides a compressed air energy storage system with integrated HVAC functions, including an air compression storage system, a heat storage system, a turbine power generation system and a HVAC pipeline network 25.

[0046] The air compression storage system includes a multi-stage compressor driven by an electric motor 2 and an air storage chamber 9, wherein the multi-stage compressor includes a first compressor 3, a second compressor 5 and a third compressor 7, wherein the inlet of the first compressor 3 is connected to an air pipeline at normal temperature and pressure, and an air filter 1 is provided on the air pipeline at normal temperature and pressure.

[0047] The heat storage system includes a first heat exchanger 4, a second heat exchanger 6, a third heat exchanger 8, a first air heater 11, a second air heater 13, a low temperature storage tank 23, a high temperature storage tank 17, a cooling tower 22, a high temperature delivery pump 18, a variable frequency pump 19 and a low temperature delivery pump 24. The turbine power generation system includes a first turbine 12, a second turbine 14 and a generator 16.

[0048] In one embodiment, the two ends of the air side of the first heat exchanger 4 are connected to the outlet of the first compressor 3 and the inlet of the second compressor 5 through pipelines, the two ends of the air side of the second heat exchanger 6 are connected to the outlet of the second compressor 5 and the inlet of the third compressor 7 through pipelines, the two ends of the air side of the third heat exchanger 8 are connected to the outlet of the third compressor 7 and the air inlet end of the air storage chamber 9 through pipelines, the air outlet end of the air storage chamber 9 is connected to one end of the air side of the first air heater 11 through the first pipeline, the other end of the air side of the first air heater 11 is connected to the inlet of the first turbine 12 through the second pipeline, the outlet of the first turbine 12 is connected to the air side of the second air heater 13, the third pipeline and the inlet of the second turbine 14 in sequence, the outlet of the second turbine 14 is connected to the HVAC pipeline network 25, the first turbine 12 and the second turbine 14 drive the generator 16 to complete the conversion of compressed air storage energy into electrical energy.

[0049] The outlet of the low-temperature storage tank 23 is connected to the inlet of the low-temperature delivery pump 24, and the outlet of the low-temperature delivery pump 24 is respectively connected to the first end of the heat exchange medium side of the third heat exchanger 8, the first end of the heat exchange medium side of the second heat exchanger 6 and the first end of the heat exchange medium side of the first heat exchanger 4, the second end of the heat exchange medium side of the third heat exchanger 8, the second end of the heat exchange medium side of the second heat exchanger 6 and the second end of the heat exchange medium side of the first heat exchanger 4 are connected to the inlet of the high-temperature storage tank 17, the first outlet of the high-temperature storage tank 17 is connected to the first end of the heat exchange medium side of the high-temperature delivery pump 18 and the first air heater 11 in sequence, the second end of the heat exchange medium side of the first air heater 11 is connected to the first end of the fourth pipeline and the first end of the fifth pipeline respectively, the second end of the fourth pipeline is connected to the heat user, the cooling tower 22 and the inlet of the low-temperature storage tank 23 in sequence, and the second end of the fifth pipeline is connected to the cooling tower 22 and the inlet of the low-temperature storage tank 23 in sequence.

[0050] The second outlet of the high temperature storage tank 17 is connected to the variable frequency pump 19 and the first end of the heat exchange medium side of the second air heater 13 in sequence, and the second end of the heat exchange medium side of the second air heater 13 is connected to the first end of the fourth pipeline and the first end of the fifth pipeline respectively.

[0051] In one embodiment, an air source auxiliary regulating valve 10 or an air source auxiliary regulating valve group is provided on the first pipeline, a first inlet regulating valve 26 is provided on the second pipeline, a second inlet regulating valve 27 is provided on the third pipeline, a first flow regulating valve 20 is provided on the fourth pipeline, and a second flow regulating valve 21 is provided on the fifth pipeline.

[0052] In one embodiment, a silencer 15 is disposed between the outlet of the second turbine 14 and the HVAC pipe network 25 .

[0053] The working process of the compressed air energy storage system of this embodiment is as follows: During the compressed energy storage process, air at normal temperature and pressure passes through the air filter 1 and enters the first compressor 3, the second compressor 5, and the third compressor 7 driven by the motor 2 in sequence. The first heat exchanger 4, the second heat exchanger 6, and the third heat exchanger 8 of the heat storage system cool the high-temperature air at the outlet of each compressor, and the heat is transferred from the compressed air to the heat exchange medium, so that the compression heat obtained by the conversion of the valley electricity is decoupled and stored from the pressure potential energy of the air. The heat exchange medium is stored in the low-temperature storage tank 23 and the high-temperature storage tank 17 respectively.

[0054] During the heat storage process, the low-temperature delivery pump 24 delivers the heat exchange medium from the low-temperature storage tank 23 to the first heat exchanger 4, the second heat exchanger 6, and the third heat exchanger 8 respectively, and the high-temperature heat exchange medium after heat exchange is stored in the high-temperature storage tank 17. The high-pressure air cooled by the heat exchange medium is stored in the air storage chamber 9. During the energy release process, the heat exchange medium is delivered to the first air heater 11 and the second air heater 13 by the high-temperature delivery pump 18 and the variable frequency pump 19 respectively to heat the compressed air. The high-pressure air enters the first air heater 11 after passing through the air source auxiliary regulating valve 10. The air that obtains the stored heat enters the first turbine 12 after passing through the first inlet regulating valve 26 to expand and do work. The compressed air after expansion and cooling enters the second air heater 13 again, and enters the second turbine 14 after heating. The first turbine 12 and the second turbine 14 drive the generator 16 to complete the conversion of the compressed air storage energy into electrical energy.

[0055] Different from the conventional compressed air energy storage power generation process, the compressed air energy storage system of the embodiment of the present invention is provided with a high temperature delivery pump 18 and a variable frequency pump 19 on the fluid pipeline from the high temperature storage tank 17 to the first air heater 11 and the second air heater 13. The variable frequency pump 19 adjusts the flow of the heat exchange medium entering the second air heater 13, thereby changing the compressed air inlet temperature of the second turbine 14. According to the change of seasons, the exhaust temperature of the second turbine 14 is adjusted to the heating or cooling requirement, and directly enters the heating or cooling space through the HVAC pipe network 25. The heat exchange medium flowing out of the first air heater 11 and the second air heater 13 is distributed through the first flow regulating valve 20 or the second flow regulating valve 21 to provide heat to the heat user. A bypass is provided in the cooling tower 22, the first end of the bypass is connected to the second end of the fifth pipeline and the heat user, and the second end of the bypass is connected to the inlet of the low temperature storage tank 23. A temperature sensor is provided in front of the first end of the bypass to obtain the temperature of the heat exchange medium at the inlet of the first end of the bypass. The operating state can be adjusted according to the temperature of the heat exchange medium at the inlet of the first end of the bypass, that is, whether the cooling tower 22 is put into operation can be controlled.

[0056] For example, if the temperature of the heat exchange medium entering the first end of the bypass meets the preset value, it does not need to be put into the cooling tower 22. When the temperature of the heat exchange medium entering the first end of the bypass is higher than the preset value, the cooling tower 22 is started to cool the heat exchange medium input from the heat user or the fifth pipeline before entering the low-temperature storage tank 23. When the temperature before the first end of the bypass is lower than the preset value, the heat exchange medium directly enters the low-temperature storage tank 23 through the bypass. By setting a bypass in the cooling tower 22, the operation of the cooling tower is controlled by the temperature of the inlet heat exchange medium, reducing the ineffective working time of the cooling tower 22, thereby reducing energy consumption.

[0057] In one embodiment, when water is used as the preferred heat exchange medium, hot water can be directly supplied to heat users, thus saving the heat exchange step, and using water as the heat exchange medium has a lower cost.

[0058] It should be noted that water is only an example of a heat exchange medium, and other media can also be used to achieve the same technical effect.

[0059] like Figure 2 As shown, in one embodiment, the heat storage system also includes a third air heater 30, wherein two ends of the air side of the third air heater 30 are respectively connected to the air side of the second air heater 13 and the third pipeline, and two ends of the heat exchange medium side of the third air heater 30 are respectively connected to the variable frequency pump 19 and the first end of the heat exchange medium side of the second air heater 13.

[0060] Furthermore, a first bypass valve 28 is provided on the heat exchange medium side of the third air heater 30 , and a second bypass valve 29 is provided on the air side of the third air heater 30 .

[0061] In this embodiment, the second air heater 13 is changed to a type in which the second air heater 13 and the third air heater 30 are connected in series. When the exhaust temperature of the second turbine 14 is too high, the first bypass valve 28 and the second bypass valve 29 are opened to change the heat exchange end difference, thereby reducing the inlet temperature and exhaust temperature of the second turbine 14, and further improving the ability of the turbine to regulate its exhaust temperature when operating in variable conditions.

[0062] In one embodiment, in order to ensure full load operation and sufficient operating adjustment range after the stored gas is partially consumed, the gas storage chamber 9 is preferably configured as more than two independent chambers, or pipeline steel is used to store and release compressed air in groups.

[0063] It should be understood by those skilled in the art that increasing or decreasing the number of compressors in an air compression storage system and increasing or decreasing the number of turbines in a turbine power generation system do not depart from the spirit and scope of the technical solutions of the various embodiments of the present invention.

[0064] An embodiment of the present invention further provides a control method for a compressed air energy storage system with integrated HVAC function, comprising the following steps:

[0065] S1. The first compressor 3, the second compressor 5 and the third compressor 7 are driven by the electric motor 2 to compress the air at normal temperature and pressure.

[0066] S2. The heat exchange medium is transported from the low-temperature storage tank 23 to the heat exchange medium side of the first heat exchanger 4, the heat exchange medium side of the second heat exchanger 6, and the heat exchange medium side of the third heat exchanger 8 through the low-temperature delivery pump 24 to exchange heat with the high-temperature air at the outlets of the first compressor 3, the second compressor 5, and the third compressor 7, and the high-temperature heat exchange medium after heat exchange is transported to the high-temperature storage tank 17 for storage, and the high-pressure air after heat exchange is stored in the air storage chamber 9.

[0067] S3. When high-pressure air is transported from the air storage chamber 9 to the air side of the first air heater 11 through the first pipeline, heat exchange medium is transported to the heat exchange medium side of the first air heater 11 through the high-temperature delivery pump 18 to heat the compressed air on the air side of the first pipeline, and the compressed air that obtains the stored heat is input into the first turbine 12 through the second pipeline to expand and perform work.

[0068] S4. The heat exchange medium is transported to the heat exchange medium side of the second air heater 13 through the variable frequency pump 19 to heat the compressed air on the air side of the second air heater 13. The heated compressed gas enters the second turbine 14 through the third pipeline, and drives the generator 16 to work through the first turbine 12 and the second turbine 14.

[0069] S5. The flow rate of the heat exchange medium entering the second air heater 13 is adjusted by the variable frequency pump 19, the compressed air inlet temperature of the second turbine 14 is changed, the exhaust steam temperature of the second turbine 14 is adjusted to the heating or cooling requirement, and directly enters the heating or cooling space through the HVAC pipe network 25.

[0070] In this step, the exhaust temperature of the second turbine 14 is adjusted to the required temperature for heating or cooling as follows:

[0071] S51. When the exhaust temperature of the second turbine 14 is lower than the second preset value, the flow rate of the heat exchange medium is increased by the variable frequency pump 19, so that the temperature of the compressed air entering the second turbine 14 increases, and the exhaust temperature also increases accordingly.

[0072] S52. When the exhaust temperature of the second turbine 14 exceeds the first preset value, the flow rate of the heat exchange medium is reduced by the variable frequency pump 19, so that the temperature of the compressed air entering the second turbine 14 is reduced, and the exhaust temperature is also reduced accordingly.

[0073] In this step, the turbine exhaust temperature regulation capability is further improved by controlling the variable frequency pump 19, and the HVAC function can be fully realized.

[0074] S53. Preset the throttling degree for the first inlet regulating valve 26 on the second pipeline and the second inlet regulating valve 27 on the third pipeline. When the exhaust temperature of the second turbine 14 is too high, that is, exceeds the first preset value, open the second inlet regulating valve 27, or open the first inlet regulating valve 26 and the second inlet regulating valve 27. At this time, the expansion pressure ratio of each stage of the turbine increases and the exhaust temperature decreases accordingly.

[0075] S54, when the exhaust temperature of the second turbine 14 is too low, that is, lower than the second preset value, the second inlet regulating valve 27 can be closed, or the first inlet regulating valve 26 and the second inlet regulating valve 27 can be closed. As the turbine expansion pressure ratio decreases, the exhaust temperature increases accordingly.

[0076] In this step, bidirectional regulation of the exhaust temperature of the second turbine 14 can be achieved by adjusting the opening of the first inlet regulating valve 26 and the second inlet regulating valve 27.

[0077] S6. The heat exchange medium flowing out of the heat exchange medium side of the first air heater 11 and the heat exchange medium side of the second air heater 13 is distributed through the fourth pipeline or the fifth pipeline to provide heat to heat users.

[0078] The compressed air energy storage system of the embodiment of the present invention can realize peak power regulation while controlling the turbine exhaust temperature in real time through adjustment means, and directly deliver cold and hot wind (air) to the space that needs cooling or heating, thereby obtaining additional use value; at the same time, it also realizes real-time control of cold and heat, and does not need to set up cold storage devices or heating water storage tanks, making the energy storage system simpler. Compared with the existing combined cooling, heat and power compressed air energy storage system, the compressed air energy storage system of the embodiment of the present invention directly supplies turbine exhaust to the space that needs cooling or heating, reducing the heat exchange link and the power generation loss; it does not require a fan coil system, eliminating a large number of fin tube heat exchangers, saving investment costs while also reducing operating and maintenance (heat exchanger cleaning, etc.) costs.

[0079] The compressed air energy storage system of the embodiment of the present invention is suitable for comprehensive energy consumption areas such as urban transportation hubs. The cooling or heating period basically coincides with the turbine power generation period. It does not need to consume electricity or other energy for cooling and heating during peak hours, and the operating cost is low. In addition, the system has a large turbine exhaust volume, and the amount of fresh air sent to the transportation hub is also large, which is a very healthy and environmentally friendly cooling and heating solution. After the air is compressed to more than 7MPa and cooled to below 40℃, almost all the moisture is precipitated. It can also be used as a HVAC system in areas with high humidity, which will greatly improve the comfort level.

[0080] Taking the application of the compressed air energy storage system of the embodiment of the present invention to the HVAC load of a certain station of a certain city subway project as an example, the compressed air energy storage system is configured as follows: Figure 1 As shown. The lighting and equipment load of the station is 112.12kW, the infiltration load of the entrance and exit is 12.4kW, the peak load of personnel is 146.57kW, the heat transfer load of the shielding door is 126.54kW, the total heat that needs to be taken away from the station is 397.63kW, and the fresh air volume demand of the station is 60.6kg / S (based on 12.6m3 / h·person, meeting the "Metro Design Specifications" and "Urban Rail Transit Technical Specifications"); the air of the compressed air heat storage system can be used as fresh air after filtration, which is different from the central air conditioning of the chiller, which needs to extract hot air from the outside for cooling as fresh air, so this part of the heat load of 107.17kW can be excluded. The subway can be equipped with two sets of compressed air energy storage systems with integrated HVAC functions, adopting a three-stage compression and two-stage expansion scheme, and using pressurized water as the heat exchange medium. Taking the summer cooling condition as an example, the main data of the specific scheme are summarized in Table 1:

[0081] Table 1

[0082]

[0083]

[0084] It can be seen from Table 1 that when the terminal difference is 10°C, the turbine exhaust temperature is 25.2°C, which fully meets the heating demand of the subway station. With the assistance of the turbine inlet regulating valve, the HVAC function can be fully realized. The air storage chamber is preferably made of pipeline steel, which stores and releases compressed air in groups, so that the turbine can operate at close to the rated pressure and flow during peak hours in the morning and evening. It can be seen from the above examples that the control method of the compressed air energy storage system of the embodiment of the present invention can be fully realized by combining the design with the specific comprehensive energy demand.

[0085] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A compressed air energy storage system with integrated HVAC function, characterized in that: It includes a first compressor, a second compressor, a third compressor, an air storage chamber, a first heat exchanger, a second heat exchanger, a third heat exchanger, a first air heater, a second air heater, a low-temperature storage tank, a high-temperature storage tank, a high-temperature delivery pump, a variable frequency pump, a low-temperature delivery pump, a first turbine, a second turbine and a generator; The inlet of the first compressor is connected to an air duct, the air side of the first heat exchanger is connected to the outlet of the first compressor and the inlet of the second compressor through a pipeline, the air side of the second heat exchanger is connected to the outlet of the second compressor and the inlet of the third compressor through a pipeline, the air side of the third heat exchanger is connected to the outlet of the third compressor and the air inlet of the air storage chamber through a pipeline, the air outlet of the air storage chamber is connected to the first pipeline, the air side of the first air heater, the second pipeline and the inlet of the first turbine in sequence, the outlet of the first turbine is connected to the air side of the second air heater, the third pipeline and the inlet of the second turbine in sequence, the outlet of the second turbine is connected to a HVAC network, and the first turbine and the second turbine are used to drive a generator to work; The outlet of the low-temperature storage tank is communicated with the inlet of the low-temperature delivery pump, and the outlet of the low-temperature delivery pump is communicated with the first end of the heat exchange medium side of the third heat exchanger, the first end of the heat exchange medium side of the second heat exchanger and the first end of the heat exchange medium side of the first heat exchanger respectively, the second end of the heat exchange medium side of the third heat exchanger, the second end of the heat exchange medium side of the second heat exchanger and the second end of the heat exchange medium side of the first heat exchanger are communicated with the inlet of the high-temperature storage tank, the first outlet of the high-temperature storage tank is communicated with the high-temperature delivery pump and the first end of the heat exchange medium side of the first air heater in sequence, the second end of the heat exchange medium side of the first air heater is communicated with the first end of the fourth pipeline and the first end of the fifth pipeline respectively, the second end of the fourth pipeline is communicated with the heat user and the inlet of the low-temperature storage tank in sequence, and the second end of the fifth pipeline is communicated with the inlet of the low-temperature storage tank; The second outlet of the high-temperature storage tank is connected with the variable frequency pump and the first end of the heat exchange medium side of the second air heater in sequence, and the second end of the heat exchange medium side of the second air heater is connected with the first end of the fourth pipeline and the first end of the fifth pipeline respectively; the variable frequency pump is used to adjust the flow rate of the heat exchange medium entering the second air heater, change the compressed air inlet temperature of the second turbine, adjust the exhaust temperature of the second turbine to the requirements of heating or cooling, and directly enter the heating or cooling space through the HVAC pipeline network.

2. The compressed air energy storage system with integrated HVAC function according to claim 1, characterized in that: It also includes cooling towers; Wherein, the cooling tower is arranged at the front end of the inlet of the low-temperature storage tank, and a bypass is provided in the cooling tower. The first end of the bypass is connected to the second end of the fifth pipeline and the heat user, and the second end of the bypass is connected to the inlet of the low-temperature storage tank. A temperature sensor is arranged in front of the first end of the bypass.

3. The compressed air energy storage system with integrated HVAC function according to claim 1, characterized in that: The first pipeline is provided with an air source auxiliary regulating valve or an air source auxiliary regulating valve group.

4. The compressed air energy storage system with integrated HVAC function according to claim 1, characterized in that: The second pipeline is provided with a first inlet regulating valve, and the third pipeline is provided with a second inlet regulating valve.

5. The compressed air energy storage system with integrated HVAC function according to claim 1, characterized in that: The fourth pipeline is provided with a first flow regulating valve, and the fifth pipeline is provided with a second flow regulating valve.

6. The compressed air energy storage system with integrated HVAC function according to claim 1, characterized in that: A silencer is arranged between the outlet of the second turbine and the HVAC pipe network.

7. The compressed air energy storage system with integrated HVAC function according to any one of claims 1 to 6, characterized in that: Also included is a third air heater; Among them, the two ends of the air side of the third air heater are respectively connected to the air side of the second air heater and the third pipeline, and the two ends of the heat exchange medium side of the third air heater are respectively connected to the variable frequency pump and the first end of the heat exchange medium side of the second air heater.

8. The compressed air energy storage system with integrated HVAC function according to claim 7, characterized in that: A first bypass valve is provided on the heat exchange medium side of the third air heater, and a second bypass valve is provided on the air side of the third air heater.

9. The compressed air energy storage system with integrated HVAC function according to any one of claims 1 to 6, characterized in that: An air filter is arranged on the air duct.

10. The compressed air energy storage system with integrated HVAC function according to any one of claims 1 to 6, characterized in that: The gas storage chamber includes a plurality of independent chambers.

11. A control method for a compressed air energy storage system with integrated HVAC functions according to any one of claims 1 to 10, characterized in that: The following steps are involved: The first compressor, the second compressor and the third compressor are driven by an electric motor to compress the air; The heat exchange medium is transported from the low-temperature storage tank to the heat exchange medium side of the first heat exchanger, the heat exchange medium side of the second heat exchanger, and the heat exchange medium side of the third heat exchanger through a low-temperature delivery pump to exchange heat with the high-temperature air at the outlets of the first compressor, the second compressor, and the third compressor, and the high-temperature heat exchange medium after heat exchange is transported to the high-temperature storage tank for storage, and the high-pressure air after heat exchange is stored in the air storage chamber; When high-pressure air is delivered from the air storage chamber to the air side of the first air heater through the first pipeline, a heat exchange medium is delivered to the heat exchange medium side of the first air heater through a high-temperature delivery pump to heat the compressed air on the air side of the first pipeline, and the compressed air that has obtained the stored heat is input to the first turbine through the second pipeline to expand and perform work; The heat exchange medium is transported to the heat exchange medium side of the second air heater through the variable frequency pump to heat the compressed air on the air side of the second air heater. The heated compressed gas enters the second turbine through the third pipeline and drives the generator to work through the first turbine and the second turbine. The flow rate of heat exchange medium entering the second air heater is adjusted by the variable frequency pump, the compressed air inlet temperature of the second turbine is changed, the exhaust steam temperature of the second turbine is adjusted to the heating or cooling requirement, and directly enters the heating or cooling space through the HVAC pipe network; The heat exchange medium flowing out of the heat exchange medium side of the first air heater and the heat exchange medium side of the second air heater is distributed through the fourth pipeline or the fifth pipeline to provide heat to heat users.

12. The control method of the compressed air energy storage system with integrated HVAC function according to claim 11, characterized in that: Adjusting the exhaust temperature of the second turbine to the required heating or cooling temperature includes the following steps: Preset the throttling degree for the first inlet regulating valve on the second pipeline and the second inlet regulating valve on the third pipeline, and when the exhaust temperature of the second turbine is higher than the first preset value, open the second inlet regulating valve, or open the first inlet regulating valve and the second inlet regulating valve; When the second turbine exhaust temperature is lower than the second preset value, the second inlet regulating valve is closed, or the first inlet regulating valve and the second inlet regulating valve are closed.

13. The control method of the compressed air energy storage system with integrated HVAC function according to claim 12, characterized in that: Adjusting the exhaust temperature of the second turbine to the required temperature for heating or cooling also includes the following steps: When the exhaust temperature of the second turbine is lower than the second preset value, the flow rate of the heat exchange medium is increased by the variable frequency pump, so that the temperature of the compressed air entering the second turbine is increased; When the exhaust temperature of the second turbine is higher than the first preset value, the flow rate of the heat exchange medium is reduced by the variable frequency pump, so that the temperature of the compressed air entering the second turbine is reduced.

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