Power generation system and method combining photo-thermal and compressed gas energy storage

Abstract

The invention relates to the field of energy storage, and particularly discloses a photo-thermal and compressed gas energy storage combined power generation system and method.The photo-thermal and compressed gas energy storage combined power generation system comprises a photo-thermal energy storage system, a compressed gas energy storage system, a steam turbine power generation system and a turbine power generation system; the photo-thermal energy storage system collects photo-thermal energy through the compressed gas energy storage system; the turbine power generation system communicates with the compressed gas energy storage system, and the turbine power generation system stores energy through the compressed gas energy storage system to generate power through a turbine. The steam turbine power generation system communicates with the compressed gas energy storage system, and the steam turbine power generation system stores energy through the compressed gas energy storage system for steam power generation. A cooling liquid circulation system; the cooling liquid circulation system communicates with the steam turbine power generation system, the turbine power generation system and the compressed gas energy storage system. The utilization rate of compressed gas energy storage and the utilization rate of cooling water resources can be increased, and power generation is more efficient.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of energy storage, in particular to a power generation system and method of combined photothermal compression gas energy storage. BACKGROUND

[0002] To reduce carbon emissions, efforts are made to build a clean, low-carbon, safe and efficient energy system, improve the level of clean energy utilization and the efficiency of power system operation, and the power industry proposes specific measures to fully play the role of flexible adjustment on the power supply side or reasonable allocation of energy storage. The compressed air energy storage power station has many advantages such as large scale, high efficiency, low cost, long service life, short construction period, clean and pollution-free, etc., and can replace thermal power units to provide rotational inertia for the power system, which is a new emerging power storage technology suitable for large-scale application. However, the traditional compressed air system needs fossil fuel for supplementary combustion, and the traditional fossil fuel has high energy consumption and heavy pollution, and the heat released at the outlet of the last stage of the compressor has low grade and cannot participate in the discharge process, causing waste.

[0003] Photothermal power generation relies on sunlight, resulting in unstable power output (e.g. affected by weather). By connecting the compressed air energy storage system, excess solar energy can be directly used for compressed air energy storage, and energy can be released for power generation during periods without sunlight, achieving continuous and stable power supply and reducing dependence on traditional backup power sources. The existing compressed air energy storage system and photothermal energy storage system alternate energy storage and power generation, and the energy and resource utilization rate is insufficient, especially the photothermal energy storage system cannot make the heated medium reach a high temperature for power generation due to the utilization rate of solar energy. SUMMARY

[0004] The purpose of the present application is to provide a power generation system of combined photothermal compression gas energy storage, which can improve the utilization rate of compressed gas energy storage and the utilization rate of cooling water resources, and make power generation more efficient.

[0005] The purpose of the present application can be achieved by the following technical solutions: A power generation system of combined photothermal compression gas energy storage, comprising: a photothermal energy storage system; a compressed gas energy storage system, the compressed gas energy storage system being in communication with the photothermal energy storage system, and the photothermal energy storage system collecting photothermal energy through the compressed gas energy storage system; a turbine generator system, the turbine generator system being in communication with the compressed gas energy storage system, and the turbine generator system generating power through the compressed gas energy storage system; a steam turbine generator system, the steam turbine generator system being in communication with the compressed gas energy storage system, and the steam turbine generator system generating power through the compressed gas energy storage system; A cooling liquid circulation system is connected with a steam turbine power generation system, a turbine power generation system and a compressed gas energy storage system, and the steam turbine power generation system generates steam which forms cooling water through the cooling liquid circulation system to cool the turbine power generation system and the compressed gas energy storage system.

[0006] In a further aspect, the compressed gas energy storage system comprises a plurality of compressors, a plurality of first oil-gas heat exchangers, a plurality of first gas-water heat exchangers, a cold water tank, a hot water tank, a cold oil tank, a hot oil tank and a gas storage, and the plurality of compressors, the plurality of first oil-gas heat exchangers and the plurality of first gas-water heat exchangers correspond to each other in level. The oil outlet of each first oil-gas heat exchanger is connected to the oil inlet of the photo-thermal energy storage system, the oil outlet of the photo-thermal energy storage system is connected to the hot oil tank, the oil outlet of each first oil-gas heat exchanger is connected to the oil outlet of the cold oil tank, the gas inlet of each first oil-gas heat exchanger is connected to the gas outlet of the corresponding compressor, the gas outlet of each first oil-gas heat exchanger is connected to the gas inlet of the corresponding first gas-water heat exchanger, the gas outlet of the corresponding first gas-water heat exchanger is connected to the gas inlet of the next stage compressor, the gas outlet of the last stage first gas-water heat exchanger is connected to the gas inlet of the gas storage, the gas outlet of each compressor is connected to the gas inlet of a first oil-gas heat exchanger, the water inlet of each first gas-water heat exchanger is connected to the water outlet of the cold water tank, and the water outlet of each first gas-water heat exchanger is connected to the water inlet of the hot water tank.

[0007] In a further aspect, the turbine power generation system comprises a plurality of turbines, a plurality of second oil-gas heat exchangers and a second gas-water heat exchanger, the water inlet of the second gas-water heat exchanger is connected to the water outlet of the hot water tank, the water outlet of the second gas-water heat exchanger is connected to the water inlet of the cold water tank, the plurality of turbines and the plurality of second oil-gas heat exchangers correspond to each other in level, the gas inlet of the second gas-water heat exchanger is connected to the gas storage, the gas outlet of the second gas-water heat exchanger is connected to the gas inlet of the first stage second oil-gas heat exchanger of the plurality of turbines, the gas inlet of each turbine is connected to the gas outlet of the corresponding second oil-gas heat exchanger, the gas outlet of each turbine is connected to the gas inlet of the next stage second oil-gas heat exchanger, the gas outlet of the last stage turbine is not connected to the gas inlet of the next stage second oil-gas heat exchanger, the oil inlet of each second oil-gas heat exchanger is connected to the oil outlet of the hot oil tank, and the oil outlet of each second oil-gas heat exchanger is connected to the oil inlet of the cold oil tank.

[0008] Further, the steam turbine power generation system comprises a steam turbine generator and a steam heat transfer oil heat exchanger, the steam heat transfer oil heat exchanger is communicated with the hot oil tank at an oil inlet end, and communicated with the cold oil tank at an oil outlet end, the steam inlet end of the steam heat transfer oil heat exchanger is communicated with the cooling liquid outlet end of the cooling liquid circulation system, the steam outlet end of the steam heat transfer oil heat exchanger is communicated with the steam inlet end of the steam turbine generator, and the steam outlet end of the steam turbine generator is communicated with the cooling liquid inlet end of the cooling liquid circulation system.

[0009] Further, the cooling liquid circulation system comprises an air cooling device, the cooling liquid inlet end of the air cooling device is communicated with the steam outlet end of the steam turbine generator, and the cooling liquid outlet end of the air cooling device is communicated with the cooling liquid inlet end of each stage compressor and turbine, and the cooling liquid outlet end of each stage compressor and turbine is communicated with the cooling liquid inlet end of the air cooling device.

[0010] Further, the above-mentioned photo-thermal combined compression gas energy storage power generation system further comprises a pump, which is communicated between the outlet and inlet ends of the cold oil tank, the hot oil tank, the cold water tank and / or the hot water tank.

[0011] Further, the photo-thermal energy storage system is a trough type concentrating collector or a tower type concentrating collector.

[0012] The application further provides a photo-thermal combined compression gas energy storage power generation method, comprising the following steps: The gas is compressed by the compression gas energy storage system, and the heat exchange medium is controlled to exchange heat with the compressed gas during the compression of the gas, and the heat exchange medium is heated; The heated heat exchange medium is introduced into the photo-thermal energy storage system to absorb photo-thermal energy storage; The heat exchange medium absorbing the photo-thermal energy storage is controlled to be divided into two paths, one of which is introduced into the turbine power generation system to exchange heat with the compressed gas after heat exchange to increase the temperature of the compressed gas, the compressed gas with the increased temperature is introduced into the turbine power generation system to generate power, and the other path is introduced into the steam turbine power generation system to exchange heat with the steam to increase the temperature of the steam, and the steam with the increased temperature is introduced into the steam turbine power generation system to generate power; The steam after heat exchange in the steam turbine power generation system is condensed into cooling water by the cooling liquid circulation system, and the cooling water is introduced into the turbine power generation system and the compression gas energy storage system to dissipate the heat generated by the turbine power generation system and the compression gas energy storage system.

[0013] In a further scheme, the heat exchange medium comprises heat-conducting oil and water, and the compressed gas is first exchanged with the heat-conducting oil and then with water to recover heat, and then is introduced into the gas storage for storage, when the electricity generated by the heat exchange medium absorbing light heat energy through the steam turbine power generation system exceeds the preset power generation requirement, the excess electricity can be stored in the compressed gas energy storage system, when the electricity generated by the heat exchange medium absorbing light heat energy through the steam turbine power generation system is lower than the preset power generation requirement, the compressed gas stored in the gas storage can be introduced into the turbine power generation system to generate electricity, and the power generation capacity is increased to the preset power generation requirement.

[0014] In a further scheme, the step further comprises introducing the heat-conducting oil into the light heat energy storage system after being exchanged with the oil gas heat exchanger at a temperature of 250 DEG C or higher, and storing the heat-conducting oil in a hot oil tank when the temperature of the heat-conducting oil is greater than or equal to 500 DEG C.

[0015] Advantages of the present application: The light heat energy storage system of the present application can further improve the energy collected by the compressed gas energy storage system, and more energy can be generated by the turbine power generation system and the steam turbine power generation system, and two sets of power generation systems are adopted, wherein the steam turbine power generation system is used for normal power generation of the light heat system, and the turbine power generation system is used for the expansion side of the compressed air energy storage. During the day when the sunlight condition is good, the steam turbine power generation system normally operates, and a part of the system power is used to maintain the power grid supply, and a part is used for the compressed air energy storage; at night, no sunlight is supplied, in order to maintain the system power, the compressed air is released from the gas storage, and the turbine power generation system of the expansion side is put into operation; on cloudy days when the sunlight condition is not good, the compressed air is also released from the gas storage, and the turbine power generation system of the expansion side is put into operation. The steam generated by the steam turbine power generation system is cooled by the cooling liquid circulation system to form cooling water, and then cools the turbine power generation system and the compressed gas energy storage system, and the cooling water is recycled to improve the resource utilization rate.

[0016] Compared with the traditional compressed air energy storage system, the heat exchange medium compressed air energy storage system can make the temperature of the heat exchange medium entering the photo-thermal energy storage system reach above 250 degrees Celsius, and the photo-thermal energy storage system can further heat the heat exchange medium, so that the temperature of the heat exchange medium is increased from 250 degrees Celsius to above 550 degrees Celsius, and the steam in the steam turbine power generation system and / or the gas in the turbine power generation system is preheated, and then the power generation system generates power to supply power to the compressed air energy storage system, so that the high-temperature heat of the photo-thermal energy is directly used to drive the air compression process, the intermediate conversion link is reduced, the overall system efficiency can be improved (estimated to be increased by 10-20%), and energy waste is reduced. The steam turbine power generation system and the turbine power generation system share a closed cooling water system, and the cooling water system can not only cool the compressor and the turbine, but also cool the steam and supply backwater, thereby improving the utilization rate of the cooling water. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0018] Figure 1 It is a photo-thermal combined compressed gas energy storage power generation system in the embodiments of the present application. Figure 2 It is a connection diagram of the cooling liquid circulating system in the embodiments of the present application. In the figure: 1, compressed gas energy storage system; 11, compressor; 12, first oil-gas heat exchanger; 13, first gas-water heat exchanger; 14, cold water tank; 15, hot water tank; 16, cold oil tank; 17, hot oil tank; 18, gas storage; 2, photo-thermal energy storage system; 3, cooling liquid circulating system; 31, air cooling device; 4, steam turbine power generation system; 41, steam turbine generator; 42, steam heat transfer oil heat exchanger; 5, turbine power generation system; 51, turbine; 52, second oil-gas heat exchanger; 53, second gas-water heat exchanger; 6, pump. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0020] As Figure 1As shown, a combined photothermal compression gas energy storage power generation system, comprising: a photothermal energy storage system 2; a compressed gas energy storage system 1, which is in communication with the photothermal energy storage system 2, and the photothermal energy storage system 2 collects photothermal energy through the compressed gas energy storage system 1; a turbine generator system 5, which is in communication with the compressed gas energy storage system 1, and the turbine generator system 5 generates electricity through the compressed gas energy storage system 1; a steam turbine generator system 4, which is in communication with the compressed gas energy storage system 1, and the steam turbine generator system 4 generates electricity through the compressed gas energy storage system 1; a cooling liquid circulation system 3, which is in communication with the steam turbine generator system 4, the turbine generator system 5 and the compressed gas energy storage system 1 respectively, and the steam turbine generator system 4 generates steam, which forms cooling water through the cooling liquid circulation system 3, and then cools the turbine generator system 5 and the compressed gas energy storage system 1.

[0021] The working principle or specific implementation is as follows: the compressed gas energy storage system 1 exchanges heat with the heat exchange medium to heat the heat exchange medium, the compressed gas energy storage system 1 is in communication with the photothermal energy storage system 2, and the heated heat exchange medium is input into the photothermal energy storage system 2 to continue to absorb photothermal energy, and the heat exchange medium absorbing photothermal energy is divided into two paths, the turbine generator system 5 is in communication with the compressed gas energy storage system 1, and one path is input into the turbine generator system 5 to reheat with the heat-exchanged compressed gas to increase the temperature of the compressed gas, and the compressed gas with increased temperature is input into the turbine generator system 5 to generate electricity, the steam turbine generator system 4 is in communication with the compressed gas energy storage system 1, and the other path is input into the steam turbine generator system 4 to exchange heat with the steam to increase the temperature of the steam, and the steam with increased temperature is input into the steam turbine generator system 4 to generate electricity, the cooling liquid circulation system 3 is in communication with the steam turbine generator system 4, the turbine generator system 5 and the compressed gas energy storage system 1 respectively, and the steam exchanged by the steam turbine generator system 4 is condensed into cooling water and input into the turbine generator system 5 and the compressed gas energy storage system 1 to dissipate the heat generated by the work of the turbine generator system 5 and the compressed gas energy storage system 1. The arrows in the figure represent the direction of light or the direction of gas-liquid flow.

[0022] The heat of the compressed gas in the compressed gas energy storage system 1 is absorbed by the heat exchange medium, and the heat of the compressed gas is reduced, so that the compressed gas with low temperature and high pressure can be obtained, which is convenient for stable storage. The heat exchange medium can be reheated by the photo-thermal energy storage system 2. Since the temperature of the heat exchange medium can be increased after heat exchange, the temperature can be further increased to reach the steam heat exchange temperature of the steam turbine power generation system 4, such as 550 degrees Celsius in the present application. The steam heat exchange temperature is used for the steam turbine power generation system 4 heat exchange and power generation. If the power generation amount meets the preset power requirement, such as meeting a certain power requirement, the excess power can be stored by the compressed gas energy storage system 1. When the heating of the heat exchange medium cannot reach the steam heat exchange temperature of the steam turbine power generation system 4 due to insufficient light, the compressed gas stored before can be used to generate power by the turbine power generation system 5 to make up for the insufficient power generation of the steam turbine power generation system 4, so as to realize stable power generation and improve the energy utilization rate. The steam condensed after the steam turbine power generation system 4 heat exchange is cooled into cooling water, and the cooling water is introduced into the turbine power generation system 5 and the compressed gas energy storage system 1 for cooling of the turbine power generation system 5 and the compressed gas energy storage system 1, which can save resources and improve the utilization rate of cooling water. The system integrates the compressed gas energy storage system 1, the photo-thermal energy storage system 2, the cooling liquid circulation system 3, the steam turbine power generation system 4 and the turbine power generation system 5 into a unified system, and the medium temperature and pressure required for stable power generation are obtained through heat exchange between the systems, thereby improving the resource and energy utilization rate.

[0023] In some embodiments, the compressed gas energy storage system 1 comprises a multi-stage compressor 11, a multi-stage first oil-gas heat exchanger 12, a multi-stage first gas-water heat exchanger 13, a cold water tank 14, a hot water tank 15, a cold oil tank 16, a hot oil tank 17 and a gas storage 18. The multi-stage compressor 11, the multi-stage first oil-gas heat exchanger 12 and the multi-stage first gas-water heat exchanger 13 are one-to-one corresponding. The oil outlet end of each first oil-gas heat exchanger 12 is connected to the oil inlet end of the photo-thermal energy storage system 2, and the oil outlet end of the photo-thermal energy storage system 2 is connected to the hot oil tank 17. The oil outlet end of each first oil-gas heat exchanger 12 is connected to the oil outlet end of the cold oil tank 16. The gas inlet end of each first oil-gas heat exchanger 12 is connected to the gas outlet end of the corresponding compressor 11. The gas outlet end of each first oil-gas heat exchanger 12 is connected to the gas inlet end of the corresponding first gas-water heat exchanger 13. The gas outlet end of the corresponding first gas-water heat exchanger 13 is connected to the gas inlet end of the next stage compressor 11. The gas outlet end of the last stage first gas-water heat exchanger 13 is connected to the gas inlet end of the gas storage 18. The gas outlet end of each compressor 11 is connected to the gas inlet end of a first oil-gas heat exchanger 12. The water inlet end of each first gas-water heat exchanger 13 is connected to the water outlet end of the cold water tank 14. The water outlet end of each first gas-water heat exchanger 13 is connected to the water inlet end of the hot water tank 15.

[0024] The compressed gas of each stage compressor 11 is exchanged by each stage oil-gas heat exchanger, and the compressed gas after each stage heat exchange is exchanged again by water-gas heat exchanger, and then is input into the next stage compressor 11. In this way, the compressed gas can obtain stable temperature through multi-stage compression and multi-stage heat exchange, the medium temperature of heat exchange is controlled at the required stable value, the stability of the compressed gas energy storage system 1 is improved, and the heat exchange medium input into the photo-thermal energy storage system 2 reaches the preset temperature requirement. Through heat exchange, the heat of the compressed gas can be reduced for storage, and the heat of the compressed gas is also utilized, thereby improving the energy utilization rate.

[0025] If a 4-stage compressor 11 is adopted, the rated exhaust volume of the first stage compressor 11 is 120 m 3 / min, the compression ratio is 1.5, the inlet pressure is 0.1 MPa, the outlet pressure is 0.15 MPa, and a 4 m 3 buffer tank is matched; the compression ratio of the second stage compressor 11 is 2.0, the outlet pressure is 0.3 MPa, and the buffer tank volume is 6 m 3 ; the compression ratio of the third stage compressor 11 is 3.0, the outlet pressure is 0.9 MPa, and the buffer tank volume is 8 m 3 ; the compression ratio of the last stage compressor 11 is 4.0, the outlet pressure is 3.6 MPa, and the buffer tank volume is 10 m 3 . Each stage compressor 11 adopts a screw structure, and the motor power is 500 kW, 800 kW, 1200 kW and 1800 kW respectively. The heat exchange area of the first oil-gas heat exchanger 12 is 200 m 2 , the shell diameter is 1.2 m, the length is 6 m, 300 heat exchange pipes with φ25*2 mm are arranged inside, the pipe flow rate is 1.5 m / s, and the shell flow rate is 8 m / s. Under the design condition, the inlet compressed gas temperature is 180℃, the outlet temperature is 80℃; the inlet heat conduction oil temperature is 50℃, the outlet temperature is 150℃, the heat exchange amount is 2.5 MW, and the dirt coefficient is 0.0002 m 2 •℃ / W. The gas storage 18 adopts a salt cavern gas storage 18, the effective volume of a single cavern is 500,000 m 3 , the well depth is 1200 m, the casing diameter is 244.5 mm, the production casing material is P110 steel grade. The working pressure range is 8-12 MPa, the maximum working temperature is 50℃, an injection-production integrated pipe column is adopted, the wellhead device pressure rating is 20 MPa, a Rosemount 3051 pressure transmitter and a Pt100 temperature sensor are matched, and the data sampling frequency is 1 time / minute.

[0026] The heat-conducting mineral oil is selected as the heat exchange medium, and air is selected as the compressed gas in the compressed gas energy storage system 1. The heat generated by the compressor 11 when compressing air is used to heat the heat-conducting oil in the oil-gas heat exchanger, so that the heat-conducting oil can be heated to above 250°C, such as 260°C. The heat provided by the photo-thermal energy storage system 2 is used to heat the heat-conducting oil to 550°C, which is used as auxiliary for the first-stage heating of the compressor 11, so as to effectively reduce the area of the photo-thermal mirror field. Through the design of the two-stage heating structure of the heat-conducting oil, the compressed air energy storage system and the photo-thermal energy storage system 2 can share one set of heat-conducting oil circulation loop, and the number of equipment can be further reduced.

[0027] In some embodiments, the turbine power generation system 5 comprises a plurality of stages of turbines 51, a plurality of stages of second oil-gas heat exchangers 52, and a second gas-water heat exchanger 53. The water inlet end of the second gas-water heat exchanger 53 is connected to the water outlet end of the hot water tank 15, and the water outlet end of the second gas-water heat exchanger 53 is connected to the water inlet end of the cold water tank 14. The stages of the plurality of stages of turbines 51 and the plurality of stages of second oil-gas heat exchangers 52 correspond to each other. The air inlet end of the second gas-water heat exchanger 53 is connected to the gas storage 18, and the air outlet end of the second gas-water heat exchanger 53 is connected to the air inlet end of the first-stage second oil-gas heat exchanger 52 in the plurality of stages of turbines 51. The air inlet end of each stage of turbines 51 is connected to the air outlet end of the corresponding stage of second oil-gas heat exchangers 52, and the air outlet end of each stage of turbines 51 is connected to the air inlet end of the next stage of second oil-gas heat exchangers 52. The air outlet end of the last stage of turbines 51 can not be connected to the air inlet end of the next stage of second oil-gas heat exchangers 52. The oil inlet end of each stage of second oil-gas heat exchangers 52 is connected to the oil outlet end of the hot oil tank 17, and the oil outlet end of each stage of second oil-gas heat exchangers 52 is connected to the oil inlet end of the cold oil tank 16.

[0028] The steam turbine power generation system 4 comprises a steam turbine generator 41 and a steam heat transfer oil heat exchanger 42, the oil inlet end of the steam heat transfer oil heat exchanger 42 is communicated with the hot oil tank 17, the oil outlet end of the steam heat transfer oil heat exchanger 42 is communicated with the cold oil tank 16, the steam inlet end of the steam heat transfer oil heat exchanger 42 is communicated with the coolant outlet end of the coolant circulation system 3, the steam outlet end of the steam heat transfer oil heat exchanger 42 is communicated with the steam inlet end of the steam turbine generator 41, and the steam outlet end of the steam turbine generator 41 is communicated with the coolant inlet end of the coolant circulation system 3. Two sets of power generation systems, wherein the steam turbine power generation system 4 adopts a steam turbine for normal power generation of the solar thermal system, and the turbine power generation system 5 adopts a compressed air turbine for the expansion side of the compressed air energy storage. During the day when the sunlight condition is good, the steam turbine power generation system 4 normally operates, and part of the system power is used to maintain the power grid supply, and part of the system power is used for the compressed air energy storage; at night, since there is no sunlight supply, in order to maintain the system power, the compressed air is released from the air storage 18, and the turbine power generation system 5 of the expansion side is put into power generation; when the sunlight condition is poor on cloudy days, in order to maintain the system power, the compressed air is also released from the air storage 18, and the turbine power generation system 5 of the expansion side is put into power generation.

[0029] As shown in Figure 2 In some embodiments, the coolant circulation system 3 comprises an air cooling device 31, the coolant inlet end of the air cooling device 31 is communicated with the steam outlet end of the steam turbine generator 41, the coolant outlet end of the air cooling device 31 is communicated with the coolant inlet end of each stage of compressor 11 and turbine 51, and the coolant outlet end of each stage of compressor 11 and turbine 51 is communicated with the coolant inlet end of the air cooling device 31. The steam turbine power generation system 4 and the turbine power generation system 5 share a closed cooling water system, and the cooling water system can not only cool the compressor 11 and the turbine 51, but also cool the steam and supply backwater, thereby improving the utilization rate of the cooling water.

[0030] As shown in Figure 1 In some embodiments, a pump 6 is further included, the pump 6 is communicated between the outlet and inlet ends of the cold oil tank 16, the hot oil tank 17, the cold water tank 14 and / or the hot water tank 15, and the heat transfer oil is pumped into or pumped out of the cold oil tank 16, the hot oil tank 17, the hot water tank 15 and / or the cold water tank 14 through the pump 6. In this way, the flow of the heat transfer medium is facilitated, and the electric energy used by the pump 6 can be supplied through the above-mentioned power generation system.

[0031] In some embodiments, the solar thermal energy storage system 2 is a trough type concentrating collector or a tower type concentrating collector. The trough type concentrating collector is shown in FIG. 1, and the inclination angle thereof is 25°, facilitating light collection.

[0032] In the embodiment of the present application, a power generation method for the combined solar thermal and compressed gas energy storage is further provided, comprising the following steps: S1, multi-stage compression of the gas by the compressed gas energy storage system 1, and controlling heat exchange between the heat exchange medium and the compressed gas during the compression of the gas to heat the heat exchange medium; S2, passing the heated heat exchange medium into the photo-thermal energy storage system 2 to absorb photo-thermal energy by the photo-thermal energy storage system 2; S3, controlling the heat exchange medium that absorbs the photo-thermal energy to be divided into two paths, controlling one path to be passed into the turbine generator system 5 to re-heat the compressed gas after heat exchange to increase the temperature of the compressed gas for power generation of the turbine generator system 5, and controlling the other path to be passed into the steam turbine generator system 4 to re-heat the steam to increase the temperature of the steam for power generation of the steam turbine generator system 4; S4, condensing the steam after heat exchange of power generation of the steam turbine generator system 4 into cooling water by the cooling liquid circulation system 3 and passing the cooling water into the turbine generator system 5 and the compressed gas energy storage system 1 for cooling of the turbine generator system 5 and the compressed gas energy storage system 1.

[0033] In some embodiments, the heat exchange medium includes heat conducting oil and water, the compressed gas is first heat exchanged with the heat conducting oil and then heat exchanged with the water to recover heat, and then is passed into the gas storage 18 for storage, when the electric quantity generated by the heat exchange medium that absorbs the photo-thermal energy by the steam turbine generator system 4 exceeds the preset power generation requirement, the excess electric quantity can be stored into the compressed gas energy storage system 1 for energy storage, when the electric quantity generated by the heat exchange medium that absorbs the photo-thermal energy by the steam turbine generator system 4 is lower than the preset power generation requirement, the compressed gas stored in the gas storage 18 can be passed into the turbine generator system 5 for power generation to increase the power generation quantity to the preset power generation requirement. For example, when the light intensity fluctuates between 400-700 W / m 2 , the mixed power generation mode is started: the photo-thermal system provides 15 MW of thermal power, 50% of the heat conducting oil 40 m 3 / h is sent into the steam turbine system to generate 12 MW of electric power; the other 50% of the heat conducting oil is sent into the turbine 51 system, and the gas storage 18 releases gas at a flow rate of 800 m 3 / h, drives the turbine 51 group to generate 8 MW of electric power after heating, and the total output is stabilized at 20 MW. The hot water tank 15 maintains a water temperature of 90℃, and the turbine inlet is preheated by the second gas-water heat exchanger 53 to save 15% of the heat conducting oil consumption.

[0034] In some embodiments, the step further comprises passing the heat-conducting oil through the oil-gas heat exchanger after heat exchange above 250 DEG C, and then into the photo-thermal energy storage system 2, and storing the heat-conducting oil in the hot oil tank 17 after the heat-conducting oil is heated by the photo-thermal energy storage system 2 to a temperature greater than or equal to 500 DEG C. The heat-conducting oil at 250 DEG C can be heated to a temperature greater than or equal to 500 DEG C after passing through the photo-thermal energy storage system 2, so that the heat of the compressed gas can be used at a maximum rate by the heat-conducting oil. For example, each stage of the compressor 11 can be connected in series with the cold oil tank 16 to rapidly reduce the temperature of the compressed gas. The number of stages of the compressor 11 can be determined according to the type of the compressor 11, and preferably four stages. The existing four-stage compressor 11 can obtain a better pressure and volume of the compressed gas.

[0035] It should be noted that the terms "first", "second", and the like in the present application are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein.

[0036] In the description of the present application, the description of the terms "one embodiment", "example", "specific example" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0037] The basic principles, main features and advantages of the present application are shown and described above. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only illustrative of the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application.

Claims

1. A solar-thermal combined with compressed gas energy storage power generation system, characterized in that: include: Solar thermal energy storage system (2); A compressed gas energy storage system (1), wherein the compressed gas energy storage system (1) is connected to a photothermal energy storage system (2), and the photothermal energy storage system (2) collects photothermal energy through the compressed gas energy storage system (1); A turbine power generation system (5), wherein the turbine power generation system (5) is connected to the compressed gas energy storage system (1), and the turbine power generation system (5) generates electricity through the energy stored in the compressed gas energy storage system (1); A steam turbine power generation system (4), wherein the steam turbine power generation system (4) is connected to the compressed gas energy storage system (1), and the steam turbine power generation system (4) generates power by storing steam through the compressed gas energy storage system (1); A cooling liquid circulation system (3); the cooling liquid circulation system (3) is connected to the steam turbine power generation system (4), the turbine power generation system (5) and the compressed gas energy storage system (1), respectively; the steam generated by the steam turbine power generation system (4) passes through the cooling liquid circulation system (3) to form cooling water, which cools the turbine power generation system (5) and the compressed gas energy storage system (1).

2. A solar-thermal combined with compressed gas energy storage power generation system according to claim 1, characterized in that: The compressed gas energy storage system (1) comprises a multi-stage compressor (11), a multi-stage first oil-gas heat exchanger (12), a multi-stage first gas-water heat exchanger (13), a cold water tank (14), a hot water tank (15), a cold oil tank (16), a hot oil tank (17) and a gas storage reservoir (18), wherein the multi-stage compressor (11), the multi-stage first oil-gas heat exchanger (12) and the multi-stage first gas-water heat exchanger (13) correspond to each other in terms of levels; The oil outlet of each stage of the first oil-gas heat exchanger (12) is connected to the oil inlet of the photothermal energy storage system (2), the oil outlet of the photothermal energy storage system (2) is connected to the hot oil tank (17), the oil outlet of each stage of the first oil-gas heat exchanger (12) is connected to the oil outlet of the cold oil tank (16), the air inlet of each stage of the first oil-gas heat exchanger (12) is respectively connected to the air outlet of the compressor (11) of the corresponding stage, and the air outlet of each stage of the first oil-gas heat exchanger (12) is respectively connected to the air inlet of the first air-water heat exchanger (13) of the corresponding stage. The air outlet of the first air-water heat exchanger (13) of the corresponding stage is connected to the air inlet of the compressor (11) of the next stage, and the air outlet of the first air-water heat exchanger (13) of the last stage is connected to the air inlet of the gas storage reservoir (18). The compressed gas outlet of each stage compressor (11) is connected to the air inlet of a first oil-gas heat exchanger (12). The water inlet of each stage first air-water heat exchanger (13) is connected to the water outlet of the cold water tank (14), and the water outlet of each stage first air-water heat exchanger (13) is connected to the water inlet of the hot water tank (15).

3. The solar-thermal combined with compressed gas energy storage power generation system according to claim 2 is characterized in that: The turbine power generation system (5) includes a multi-stage turbine (51), a multi-stage second oil-gas heat exchanger (52) and a second air-water heat exchanger (53), wherein the water inlet of the second air-water heat exchanger (53) is connected to the water outlet of the hot water tank (15), and the water outlet of the second air-water heat exchanger (53) is connected to the water inlet of the cold water tank (14). The levels of the multi-stage turbine (51) and the multi-stage second oil-gas heat exchanger (52) are in one-to-one correspondence. The air inlet of the second air-water heat exchanger (53) is connected to the air storage reservoir (18), and the air outlet of the second air-water heat exchanger (53) is connected to the multi-stage turbine (51). The air inlet of the primary second oil-gas heat exchanger (52) in the turbine (51) is connected, the air inlet of each stage of the turbine (51) is connected to the air outlet of the corresponding stage of the second oil-gas heat exchanger (52), and the air outlet of each stage of the turbine (51) is connected to the air inlet of the next stage of the second oil-gas heat exchanger (52); the air outlet of the last stage of the turbine (51) may not be connected to the air inlet of the next stage of the second oil-gas heat exchanger (52); the oil inlet of each stage of the second oil-gas heat exchanger (52) is connected to the oil outlet of the hot oil tank (17), and the oil outlet of each stage of the second oil-gas heat exchanger (52) is connected to the oil inlet of the cold oil tank (16).

4. The solar-thermal combined with compressed gas energy storage power generation system according to claim 2 is characterized in that: The steam turbine power generation system (4) includes a steam turbine generator (41) and a steam thermal oil heat exchanger (42), wherein the oil inlet end of the steam thermal oil heat exchanger (42) is connected to the hot oil tank (17), the oil outlet end of the steam thermal oil heat exchanger (42) is connected to the cold oil tank (16), the steam inlet end of the steam thermal oil heat exchanger (42) is connected to the coolant outlet end of the coolant circulation system (3), the steam outlet end of the steam thermal oil heat exchanger (42) is connected to the steam inlet end of the steam turbine generator (41), and the steam outlet end of the steam turbine generator (41) is connected to the coolant inlet end of the coolant circulation system (3).

5. The solar-thermal combined with compressed gas energy storage power generation system according to claim 4 is characterized in that: The cooling liquid circulation system (3) includes an air cooling device (31), wherein the cooling liquid inlet end of the air cooling device (31) is connected to the steam outlet end of the steam turbine generator (41), the cooling liquid outlet end of the air cooling device (31) is connected to the cooling liquid inlet end of each stage of the compressor (11) and the turbine (51), and the cooling liquid outlet end of each stage of the compressor (11) and the turbine (51) is connected to the cooling liquid inlet end of the air cooling device (31).

6. The solar-thermal combined with compressed gas energy storage power generation system according to claim 4 is characterized in that: The invention also includes a pump (6), which is connected to the inlet and outlet ends of the cold oil tank (16), the hot oil tank (17), the cold water tank (14) and / or the hot water tank (15).

7. The solar-thermal combined with compressed gas energy storage power generation system according to claim 1, characterized in that: The photothermal energy storage system (2) is a trough-type concentrating thermal collector or a tower-type concentrating thermal collector.

8. A method for power generation using solar thermal combined with compressed gas energy storage, characterized in that: The following steps are involved: The gas is compressed in multiple stages by a compressed gas energy storage system (1), and heat exchange between the heat exchange medium and the compressed gas is controlled during the gas compression process to increase the temperature of the heat exchange medium; Passing the heated heat exchange medium into the photothermal energy storage system (2), and absorbing the photothermal energy through the photothermal energy storage system (2); The heat exchange medium for absorbing the solar thermal energy storage is divided into two paths, one of which is controlled to be passed into the turbine power generation system (5) to exchange heat with the compressed gas after heat exchange to increase the temperature of the compressed gas, and the compressed gas with the increased temperature is passed into the turbine power generation system (5) to generate electricity, and the other is controlled to be passed into the steam turbine power generation system (4) to exchange heat with steam to increase the temperature of the steam, and the steam with the increased temperature is passed into the steam turbine power generation system (4) to generate electricity; The steam generated by the steam turbine power generation system (4) after heat exchange is condensed into cooling water through the cooling liquid circulation system (3), and the cooling water is introduced into the turbine power generation system (5) and the compressed gas energy storage system (1), so as to dissipate the heat generated by the work of the turbine power generation system (5) and the compressed gas energy storage system (1).

9. The method for power generation using solar-thermal combined with compressed gas energy storage according to claim 8, characterized in that: The heat exchange medium includes heat transfer oil and water. After the gas is compressed, it is first heat-exchanged with the heat transfer oil and then heat-exchanged with the water to recover heat, and then passed into the gas storage reservoir (18) for storage and standby. When the heat exchange medium that absorbs the light and thermal energy storage generates electricity through the steam turbine power generation system (4) and the amount of electricity generated exceeds the preset power generation requirement, the excess electricity can be stored in the compressed gas energy storage system (1) for energy storage. When the heat exchange medium that absorbs the light and thermal energy storage generates electricity through the steam turbine power generation system (4) and the amount of electricity generated is lower than the preset power generation requirement, the compressed gas stored in the gas storage reservoir (18) can be passed into the turbine power generation system (5) to generate electricity, thereby increasing the power generation to the preset power generation requirement.

10. The method for power generation using solar-thermal combined with compressed gas energy storage according to claim 9, characterized in that: The steps also include heating the heat transfer oil to above 250°C through an oil-gas heat exchanger and then passing it into the photothermal energy storage system (2), and storing the heat transfer oil in a hot oil tank (17) when the temperature of the heat transfer oil is raised to 500°C or higher through the photothermal energy storage system (2).

Images