Lubricating oil supply device, carbon dioxide energy storage system and control method thereof

Abstract

This invention discloses a lubricating oil supply device, a carbon dioxide energy storage system, and a control method thereof. The lubricating oil supply device includes a first supply unit, a second supply unit, and a third supply unit respectively connected between a lubricating oil tank and an energy storage component and an energy release component. The first supply unit is configured to supply a first quantity of lubricating oil to the energy storage component and the energy release component at a first power. The second supply unit is configured to supply a second quantity of lubricating oil to the energy storage component and the energy release component at a second power. The third supply unit is configured to supply emergency lubricating oil to the energy storage component and the energy release component. The first and second supply units switch oil supply according to the operating conditions of the energy storage component and the energy release component, with the second power being less than the first power and the second oil quantity being less than the first oil quantity. This invention not only reduces system energy consumption and lubricating oil loss, thus lowering costs, but also improves system operational safety.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon dioxide energy storage, and in particular to a lubricating oil supply device, a carbon dioxide energy storage system and a control method thereof. Background Art

[0002] Using clean energy such as solar energy and wind energy to slow down the consumption of non-renewable traditional energy such as coal and oil has become an inevitable choice. Due to the intermittent, volatile, and peak-shifting characteristics of clean energy, energy storage technology has become one of the key technologies for the development of clean energy. At present, energy storage technology based on the gas-liquid phase change cycle of carbon dioxide uses excess electricity or clean energy to compress and condense gaseous carbon dioxide at room temperature and pressure in the gas storage unit into liquid carbon dioxide and store it in the liquid storage unit during the off-peak period of electricity consumption, and stores the heat energy generated during the compression process. During the peak period of electricity consumption, the stored heat energy is used to heat the liquid carbon dioxide to gaseous state. The gaseous carbon dioxide drives the turbine to drive the generator to generate electricity, and the gaseous carbon dioxide after work returns to the gas storage unit for recycling. It has the advantages of simple structure, flexible layout, and high energy storage efficiency, and has gradually attracted widespread attention.

[0003] The CO2 energy storage system contains high-speed rotating mechanical equipment, mainly including compressors on the energy storage side and turbines on the energy release side. These high-speed rotating mechanical equipment need to be equipped with corresponding lubricating oil supply devices. In addition, in the CO2 energy storage system, the energy storage process and the energy release process are usually not carried out at the same time. Its working principle requires the units on the energy storage side and the units on the energy release side to start and stop alternately and frequently (the so-called "cyclic load").

[0004] At present, the lubricating oil supply device in the carbon dioxide energy storage system adopts a similar oil supply device to that in the generator set in the traditional thermal power generation system, which mainly includes 1 or 2 (one for use and one for standby) main working oil pumps driven by AC asynchronous motors + 1 emergency oil pump driven by DC motors, such as the technical solution disclosed in patent CN219262465U. During the operation of the carbon dioxide energy storage system, whether in the startup operating condition or the shutdown cranking condition, the main working oil pump needs to continuously supply lubricating oil to the compressor on the energy storage side and the turbine on the energy release side, and the main working oil pump needs to be driven by a high-power motor, which is usually designed according to the oil supply required for the maximum operating condition of the equipment. However, when the compressor on the energy storage side is shut down and cranked or the turbine on the energy release side is shut down and cranked, the equipment only needs a small amount of lubricating oil to meet the cranking condition requirements, but at this time the main working oil pump still supplies oil according to the larger amount of lubricating oil required to meet the startup operating condition of the equipment, which not only increases the energy consumption of the system, but also increases the loss of lubricating oil. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a lubricating oil supply device, a carbon dioxide energy storage system and a control method thereof, so as to reduce the energy consumption of the system and reduce the loss of lubricating oil.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The first aspect of the present invention is to provide a lubricating oil supply device, which is applied to a carbon dioxide energy storage system, wherein the carbon dioxide energy storage system includes an energy storage component and an energy release component, and the lubricating oil supply device includes a first oil supply unit, a second oil supply unit and a third oil supply unit respectively connected between a lubricating oil tank and the energy storage component and the energy release component; the first oil supply unit is configured to be driven by a first power to provide a first amount of lubricating oil to the energy storage component and the energy release component; the second oil supply unit is configured to be driven by a second power to provide a second amount of lubricating oil to the energy storage component and the energy release component; the third oil supply unit is configured to provide emergency lubricating oil to the energy storage component and the energy release component;

[0008] The first oil supply unit and the second oil supply unit switch oil supply according to the operating conditions of the energy storage component and the energy release component, the second power is less than the first power, and the second oil quantity is less than the first oil quantity.

[0009] In a specific embodiment, the first oil amount is 2 to 3 times the second oil amount.

[0010] In a specific solution, the first oil supply unit includes a first oil pump, a first pipeline and a first driving mechanism, the first oil pump is arranged in the lubricating oil tank, the first oil pump is connected to the energy storage component and the energy release component through the first pipeline, and the first driving mechanism is configured to drive the first oil pump with the first power to provide the first oil volume; and / or,

[0011] The second oil supply unit comprises a second oil pump, a second pipeline and a second driving mechanism, the second oil pump is arranged in the lubricating oil tank, the second oil pump is connected to the energy storage component and the energy release component through the second pipeline, and the second driving mechanism is configured to drive the second oil pump with the second power to provide the second oil volume; and / or,

[0012] The third oil supply unit includes a third oil pump, a third pipeline and a third driving mechanism. The third oil pump is arranged in the lubricating oil tank. The third oil pump is connected to the energy storage component and the energy release component through the third pipeline. The third driving mechanism is used to drive the third oil pump to provide the emergency lubricating oil.

[0013] In a specific solution, the first pipeline includes a first oil supply main pipeline, a first oil supply branch pipeline and a second oil supply branch pipeline, the first end of the first oil supply main pipeline is connected to the output end of the first oil pump, the first end of the first oil supply branch pipeline and the first end of the second oil supply branch pipeline are respectively connected to the second end of the first oil supply main pipeline, the second end of the first oil supply branch pipeline is connected to the energy storage component, the second end of the second oil supply branch pipeline is connected to the energy release component, the first oil supply branch pipeline is provided with a first oil supply valve, and the second oil supply branch pipeline is provided with a second oil supply valve;

[0014] The second pipeline includes a second oil supply main line, a third oil supply branch line and a fourth oil supply branch line, the first end of the second oil supply main line is connected to the output end of the second oil pump, the first end of the third oil supply branch line and the first end of the fourth oil supply branch line are respectively connected to the second end of the second oil supply main line, the second end of the third oil supply branch line is connected to the energy storage component, the second end of the fourth oil supply branch line is connected to the energy release component, the third oil supply branch line is provided with a third oil supply valve, and the fourth oil supply branch line is provided with a fourth oil supply valve;

[0015] The third pipeline includes a third oil supply main line, a first end of the third oil supply main line is connected to an output end of the third oil pump, and a second end of the third oil supply main line is connected to the first oil supply main line.

[0016] In a specific solution, the first driving mechanism and the second driving mechanism are driving motors respectively.

[0017] In a specific embodiment, the carbon dioxide energy storage system further includes a liquid storage unit, which is used to store liquid carbon dioxide and contains high-pressure carbon dioxide gas; the third driving mechanism includes:

[0018] A vane type rotary cylinder, connected to the third oil pump, and used for rotationally driving the third oil pump;

[0019] A gas transmission pipeline, connected between the liquid storage unit and the blade type rotary cylinder, for transmitting the high-pressure carbon dioxide gas in the liquid storage unit to the blade type rotary cylinder to drive the blade type rotary cylinder to rotate;

[0020] The energized normally closed solenoid valve is connected to the gas transmission pipeline.

[0021] In a specific embodiment, the carbon dioxide energy storage system also includes a shaft sealing gas storage container, which is used to store shaft sealing gas; the third driving mechanism also includes an exhaust pipeline, which is connected between the blade type rotary cylinder and the shaft sealing gas storage container, and is used to transport the carbon dioxide gas discharged from the blade type rotary cylinder to the shaft sealing gas storage container.

[0022] In a specific solution, a gas pressure regulating valve is provided on the gas transmission pipeline.

[0023] The second aspect of the present invention is to provide a carbon dioxide energy storage system, which includes a gas storage unit, an energy storage assembly, a liquid storage unit and an energy release assembly connected in a closed loop in sequence, and also includes the lubricating oil supply device as described above.

[0024] A third aspect of the present invention is to provide a control method for the carbon dioxide energy storage system as described above, the control method comprising:

[0025] When the energy storage component is in an energy storage operating condition and the energy release component is in a cranking operating condition, controlling the first oil supply unit to supply lubricating oil to the energy storage component, and controlling the second oil supply unit to supply lubricating oil to the energy release component;

[0026] When the energy release component is in an energy release operating condition and the energy storage component is in a cranking operating condition, controlling the first oil supply unit to supply lubricating oil to the energy release component, and controlling the second oil supply unit to supply lubricating oil to the energy storage component;

[0027] When the energy storage component and the energy release component are both in a cranking operation state, controlling the second oil supply unit to supply lubricating oil to the energy storage component and the energy release component respectively;

[0028] When the carbon dioxide energy storage system fails and the first oil supply unit and the second oil supply unit are unable to supply oil, the third oil supply unit is started to provide emergency lubricating oil to the energy storage component and the energy release component at the same time.

[0029] The lubricating oil supply device, carbon dioxide energy storage system and control method thereof provided by the embodiment of the present invention are provided with a first oil supply unit and a second oil supply unit which can be independently controlled respectively in the lubricating oil supply device: when the energy storage component or the energy release component is in the starting operation condition, the first oil supply unit with a larger power is controlled to provide a larger amount of lubricating oil required for the equipment starting operation condition; when the energy storage component or the energy release component is in the cranking operation condition, the second oil supply unit with a smaller power is controlled to provide a smaller amount of lubricating oil required for the equipment cranking operation condition. Therefore, the scheme not only reduces the energy consumption of the system, but also reduces the loss of lubricating oil and reduces the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a structural schematic diagram of a carbon dioxide energy storage system in an embodiment of the present invention;

[0031] Figure 2 It is a structural schematic diagram of a lubricating oil supply device in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical scheme and advantages of the present invention clearer, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. Examples of these preferred embodiments are illustrated in the accompanying drawings. The embodiments of the present invention shown in the accompanying drawings and described according to the accompanying drawings are merely exemplary, and the present invention is not limited to these embodiments.

[0033] It should be noted that the same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0034] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions according to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0035] See also Figure 1 and Figure 2 The embodiment of the present invention first provides a lubricating oil supply device 50 and a carbon dioxide energy storage system 100 including the lubricating oil supply device 50 .

[0036] Specifically, Figure 1As shown, the carbon dioxide energy storage system 100 mainly includes a gas storage unit 10, an energy storage component 20, a liquid storage unit 30 and an energy release component 40 which are connected in a closed loop in sequence. Among them, the gas storage unit 10 is used to store gaseous carbon dioxide at normal pressure, and the liquid storage unit 30 is used to store liquid carbon dioxide. The gaseous carbon dioxide flowing out of the gas storage unit 10 is converted into liquid carbon dioxide with a preset energy storage pressure through the energy storage component 20, and flows into the liquid storage unit 30, and energy storage is completed in this process. The liquid carbon dioxide output from the liquid storage unit 30 is converted into gaseous carbon dioxide at normal pressure by releasing energy through the energy release component 40, and flows into the gas storage unit 10, and energy release and application are completed in this process. Usually, the energy storage component 20 compresses and liquefies the gaseous carbon dioxide into liquid carbon dioxide during the off-peak period of electricity consumption or by utilizing wind and solar power abandonment, and stores it in the liquid storage unit 30, converting the energy into compression energy and heat energy storage; during the peak period of electricity consumption, the energy release component 40 gasifies and expands the liquid carbon dioxide to do work, and releases the stored energy and converts it into electrical energy for use.

[0037] The specific composition structures of the gas storage unit 10, the energy storage assembly 20, the liquid storage unit 30 and the energy release assembly 40 can be realized by referring to the existing technologies, such as the technical solutions disclosed in the existing patent documents CN116221616A, CN117628836A, and CN116857027A. The liquid storage unit 30 preferably uses a matrix self-balancing liquid storage unit as disclosed in the patent document CN222026765U.

[0038] As a specific example, in this embodiment, Figure 1 As shown, the energy storage assembly 20 mainly includes a compressor 21, an energy storage side heat exchanger 22 and a condenser 23 which are sequentially connected between the gas storage unit 10 and the liquid storage unit 30. In the compression heat release energy storage loop, the gaseous carbon dioxide is compressed by the compressor 21 and cooled by the energy storage side heat exchanger 22, and then liquefied by the condenser 23 to form liquid carbon dioxide and stored in the liquid storage unit 30.

[0039] As a specific example, in this embodiment, Figure 1 As shown, the energy release component 40 mainly includes an evaporator 41, an energy release side heat exchanger 42 and a turbine 43 which are sequentially connected between the liquid storage unit 30 and the gas storage unit 10. In the heat absorption and expansion energy release circuit, the liquid carbon dioxide absorbs heat and vaporizes and expands in the evaporator 41, is further heated and heated by the energy release side heat exchanger 42, and then releases energy by performing work (such as power generation) externally through the turbine 43, and is converted into gaseous carbon dioxide at normal pressure and stored in the gas storage unit 10.

[0040] Among them, the energy storage component 20 and the energy release component 40 both contain high-speed rotating mechanical equipment, mainly the compressor 21 in the energy storage component 20 and the turbine 43 in the energy release component 40. These high-speed rotating mechanical equipment need to be equipped with corresponding lubricating oil supply devices. In the existing related technologies, the lubricating oil supply device in the carbon dioxide energy storage system adopts a similar oil supply device to the generator set in the traditional thermal power generation system, which mainly includes 1 or 2 (one for use and one for backup) main working oil pumps driven by AC asynchronous motors + 1 emergency oil pump driven by DC motors. When the power generation system is operating normally, the generator set is provided with a large amount of lubricating oil (based on the requirements of the starting operating conditions) by the high-power main working oil pump, whether it is in the starting operating condition or the cranking operating condition. However, during the operation of the carbon dioxide energy storage system, the energy storage process and the energy release process are usually not carried out at the same time. Its working principle requires the energy storage component 20 and the energy release component 40 to be started and stopped alternately and frequently (the so-called "cyclic load"), that is, whether it is the compressor 21 in the energy storage component 20 or the turbine 43 in the energy release component 40, it is necessary to alternately and frequently switch between the starting operation condition and the cranking operation condition, that is, the total time of the high-speed rotating mechanical equipment in the cranking operation condition is relatively long, and in the cranking operation condition, the equipment only needs a small amount of lubricating oil to meet the cranking requirements. Therefore, if the same oil supply device and oil supply method as the generator set in the traditional thermal power generation system are directly used, not only the energy consumption of the system is increased, but also the loss of lubricating oil is increased.

[0041] It should be noted that the cranking operation condition refers to the following: when the rotating equipment just enters the shutdown state from the high-speed operation state, it often has a higher body temperature. In order to prevent the uneven temperature field distribution after the equipment is shut down and the thermal stress caused by the large temperature difference between the upper and lower cylinders, it is necessary to continuously turn the machine to eliminate the thermal stress caused by the temperature difference between the upper and lower cylinders until it finally stops completely.

[0042] In order to solve the above problems, the embodiment of the present invention provides a lubricating oil supply device 50, which is mainly used in the carbon dioxide energy storage system 100, that is, Figure 1 and 2 The carbon dioxide energy storage system 100 provided in the above embodiment of the present invention further includes a lubricating oil supply device 50 .

[0043] Specifically, Figure 1 and Figure 2As shown, the lubricating oil supply device 50 provided in this embodiment mainly includes a lubricating oil tank 54 and a first oil supply unit 51, a second oil supply unit 52 and a third oil supply unit 53. The first oil supply unit 51, the second oil supply unit 52 and the third oil supply unit 53 are respectively connected between the lubricating oil tank 54 and the energy storage assembly 20 and the energy release assembly 40.

[0044] The first oil supply unit 51 is configured to be driven by a first power to provide a first amount of lubricating oil to the energy storage component 20 and the energy release component 40. The second oil supply unit 52 is configured to be driven by a second power to provide a second amount of lubricating oil to the energy storage component 20 and the energy release component 40. The third oil supply unit 53 is configured to provide emergency lubricating oil to the energy storage component 20 and the energy release component 40. The second power is less than the first power, and the second amount of oil is less than the first amount of oil.

[0045] Based on the lubricating oil supply device 50 as described above, a first oil supply unit 51 and a second oil supply unit 52 which can be independently controlled are provided, and the first oil supply unit 51 and the second oil supply unit 52 switch the oil supply according to the operating conditions of the energy storage component 20 and the energy release component 40. Specifically, when the energy storage component 20 or the energy release component 40 is in the starting operating condition, the first oil supply unit 51 provides a larger first amount of lubricating oil to the energy storage component 20 or the energy release component 40 with a larger power. The first amount of lubricating oil refers to the amount of lubricating oil that can meet the starting operating conditions of the energy storage component 20 and the energy release component 40; when the energy storage component 20 or the energy release component 40 is in the cranking operating condition, the second oil supply unit 52 provides a smaller second amount of lubricating oil to the energy storage component 20 or the energy release component 40 with a smaller power. The second amount of lubricating oil refers to the amount of lubricating oil that can meet the cranking operating conditions of the energy storage component 20 and the energy release component 40. Therefore, the lubricating oil supply device 50 not only reduces the energy consumption of the system, but also reduces the loss of lubricating oil and reduces costs.

[0046] When the carbon dioxide energy storage system 100 fails and the first oil supply unit 51 and the second oil supply unit 52 are unable to supply oil, the third oil supply unit 53 is started to provide emergency lubricating oil to the energy storage component 20 and the energy release component 40 at the same time.

[0047] It should be noted that providing lubricating oil to the energy storage component 20 and the energy release component 40 as described above refers to providing lubricating oil to the rotating mechanical equipment in the energy storage component 20 and the energy release component 40, specifically the compressor 21 in the energy storage component 20 and the turbine 43 in the energy release component 40.

[0048] As a preferred solution, in this embodiment, the first oil amount is 2 to 3 times the second oil amount.

[0049] In this embodiment, Figure 2 As shown, the first oil supply unit 51 mainly includes a first oil pump 51a, a first pipeline 51b and a first driving mechanism 51c. The first oil pump 51a is disposed in the lubricating oil tank 54, and the first oil pump 51a is connected to the energy storage component 20 and the energy release component 40, specifically to the compressor 21 and the turbine 43, through the first pipeline 51b. The first driving mechanism 51c is configured to drive the first oil pump 51a at the first power to provide the first amount of lubricating oil.

[0050] Specifically, the first pipeline 51b includes a first oil supply main pipeline 511, a first oil supply branch pipeline 512, and a second oil supply branch pipeline 513. The first end of the first oil supply main pipeline 511 is connected to the output end of the first oil pump 51a, and the first end of the first oil supply branch pipeline 512 and the first end of the second oil supply branch pipeline 513 are respectively connected to the second end of the first oil supply main pipeline 511. The second end of the first oil supply branch pipeline 512 is connected to the energy storage component 20, specifically to the compressor 21. The second end of the second oil supply branch pipeline 513 is connected to the energy release component 40, specifically to the turbine 43.

[0051] Furthermore, the first oil supply branch 512 is provided with a first oil supply valve 514, and the second oil supply branch 513 is provided with a second oil supply valve 515. By controlling the opening and closing states of the first oil supply valve 514 and the second oil supply valve 515, the first oil supply unit 51 can selectively supply oil to the energy storage assembly 20 and / or the energy release assembly 40.

[0052] The first driving mechanism 51c is selected as a driving motor, specifically an AC driving motor.

[0053] In this embodiment, Figure 2 As shown, the second oil supply unit 52 mainly includes a second oil pump 52a, a second pipeline 52b and a second driving mechanism 52c. The second oil pump 52a is disposed in the lubricating oil tank 54, and the second oil pump 52a is connected to the energy storage assembly 20 and the energy release assembly 40, specifically to the compressor 21 and the turbine 43, through the second pipeline 52b. The second driving mechanism 52c is configured to drive the second oil pump 52a with the second power to provide the second oil quantity of lubricating oil.

[0054] Specifically, the second pipeline 52b includes a second main oil supply line 521, a third oil supply branch line 522 and a fourth oil supply branch line 523. The first end of the second main oil supply line 521 is connected to the output end of the second oil pump 52a, and the first end of the third oil supply branch line 522 and the first end of the fourth oil supply branch line 523 are respectively connected to the second end of the second main oil supply line 521. The second end of the third oil supply branch line 522 is connected to the energy storage component 20, specifically to the compressor 21. The second end of the fourth oil supply branch line 523 is connected to the energy release component 40, specifically to the turbine 43.

[0055] Furthermore, a third oil supply valve 524 is provided on the third oil supply branch 522, and a fourth oil supply valve 525 is provided on the fourth oil supply branch 523; by controlling the opening and closing states of the third oil supply valve 524 and the fourth oil supply valve 525, the second oil supply unit 52 can selectively supply oil to the energy storage component 20 and / or the energy release component 40.

[0056] The second driving mechanism 52c is selected as a driving motor, specifically an AC driving motor.

[0057] Among them, the power of the second driving mechanism 52c is less than the power of the first driving mechanism 51c. For example, the power of the first driving mechanism 51c is the first power, and the power of the second driving mechanism 52c is the second power. In some specific implementation schemes, the second power is 30%-50% of the first power, and the energy consumption is reduced by 40%-60%.

[0058] In this embodiment, Figure 2 As shown, the third oil supply unit 53 includes a third oil pump 53a, a third pipeline 53b and a third driving mechanism 53c. The third oil pump 53a is disposed in the lubricating oil tank 54, and the third oil pump 53a is connected to the energy storage component 20 and the energy release component 40, specifically to the compressor 21 and the turbine 43, through the third pipeline 53b. The third driving mechanism 53c is used to drive the third oil pump 53a to provide the accident lubricating oil.

[0059] Specifically, the third pipeline 53b includes a third oil supply main pipeline 531, a first end of the third oil supply main pipeline 531 is connected to the output end of the third oil pump 53a, a second end of the third oil supply main pipeline 531 is connected to the first oil supply main pipeline 511, and then connected to the compressor 21 and the turbine 43 through the first oil supply branch 512 and the second oil supply branch 513, that is, in this embodiment, the third oil supply unit 53 and the first oil supply unit 51 share a part of the oil supply pipeline. Of course, in some other embodiments, an independent oil supply branch can be set at the second end of the third oil supply main pipeline 531 to be directly connected to the compressor 21 and the turbine 43 respectively.

[0060] As described above, when the carbon dioxide energy storage system 100 fails, the third oil supply unit 53 is started to provide emergency lubricating oil to the energy storage component 20 and the energy release component 40 at the same time. In the present embodiment, the third oil supply unit 53 and the first oil supply unit 51 share the first oil supply branch 512 and the second oil supply branch 513 connected to the compressor 21 and the turbine 43. In some faults, such as a power outage in the factory causing the carbon dioxide energy storage system 100 to lose power, the first oil supply branch 512 and the second oil supply branch 513 should be kept connected. Therefore, in the present embodiment, the first oil supply valve 514 on the first oil supply branch 512 and the second oil supply valve 515 on the second oil supply branch 513 are selected as solenoid valves that are closed with power and opened without power. When the energy storage system loses power and causes the first oil supply valve 514 and the second oil supply valve 515 to lose power, both are in the open state, and the first oil supply branch 512 and the second oil supply branch 513 are kept in a connected state.

[0061] Among them, the third driving mechanism 53c can be selected as a driving motor, for example, a DC driving motor used in an existing oil supply device. In this case, it is necessary to equip the carbon dioxide energy storage system 100 with an independent DC battery and a corresponding electronic control system, so that when an accident occurs, the third oil supply unit 53 can be quickly started to provide emergency lubricating oil to ensure emergency shutdown of the unit.

[0062] In the existing related technologies, the electronic control system of the emergency oil pump (corresponding to the third oil pump 53a in the embodiment of the present invention) is relatively complex, and there are many nodes that need to be controlled, resulting in a high failure rate. The reliability of the emergency oil pump needs to be improved. If the emergency oil pump cannot be started in an emergency, it will cause a safety accident and huge economic losses. In the process of exploring solutions to this problem, the applicant of the present invention found that the reliability of the emergency oil pump can be improved by combining the power source unique to the carbon dioxide energy storage system itself and changing the driving mode of the emergency oil pump. Specifically, in the current carbon dioxide energy storage system 100, the liquid storage container provided in the liquid storage unit 30 for storing liquid carbon dioxide has a large amount of high-pressure carbon dioxide gas in the pressure-maintaining pipeline at the top of the liquid storage container during the energy storage condition or the energy release condition. This part of the high-pressure carbon dioxide gas can be used as a power source to drive the third oil pump 53a to supply oil.

[0063] Based on the above concept, in this embodiment, as a preferred solution, Figure 2 As shown, the third driving mechanism 53c includes a vane-type rotary cylinder 532, an air supply pipeline 533 and an electrically powered normally closed solenoid valve 534. The vane-type rotary cylinder 532 is connected to the third oil pump 53a, and is used to rotationally drive the third oil pump 53a. The air supply pipeline 533 is connected between the liquid storage unit 30 and the vane-type rotary cylinder 532, and is used to deliver the high-pressure carbon dioxide gas in the liquid storage unit 30 to the vane-type rotary cylinder 532, so as to drive the vane-type rotary cylinder 532 to rotate. The electrically powered normally closed solenoid valve 534 is connected to the air supply pipeline 533, and is used to control the on-off of the air supply pipeline 533, and further control whether to start the third oil pump 53a. It should be noted that the electrically powered normally closed solenoid valve 534 refers to a normally closed solenoid valve that is closed when powered on and opened when powered off.

[0064] As described above, the third driving mechanism 53c only needs to control the energized normally closed solenoid valve 534 to be powered off and opened, so that the gas transmission pipeline 533 can be conducted, thereby inputting the high-pressure carbon dioxide gas in the liquid storage unit 30 into the blade-type rotary cylinder 532, driving the blade-type rotary cylinder 532 to rotate, and then driving the third oil pump 53a to provide the accident lubricating oil. The drive control structure and the drive control process are simpler, faster and more reliable, effectively improving the reliability of the third oil supply unit (accident oil supply unit) 53, and improving the safety performance of the operation of the carbon dioxide energy storage system. In particular, when the carbon dioxide energy storage system 100 loses power, the energized normally closed solenoid valve 534 automatically loses power and opens, thereby providing the accident lubricating oil in time, with a very high response speed.

[0065] Furthermore, a gas pressure regulating valve 535 is provided on the gas supply pipeline 533 , and the pressure of the high-pressure carbon dioxide gas input to the blade-type rotary cylinder 532 is controlled by the gas pressure regulating valve 535 , thereby adjusting the rotation speed of the blade-type rotary cylinder 532 .

[0066] Typically, see Figure 1 and Figure 2 The carbon dioxide energy storage system 100 further includes a shaft sealing gas storage container 60, which is used to store shaft sealing gas. The shaft sealing gas storage container 60 is mainly used to provide shaft sealing gas to the compressor 21 and the turbine 43. In this embodiment, Figure 2 As shown, the third driving mechanism 53c also includes an exhaust pipeline 536, which is connected between the blade-type rotary cylinder 532 and the shaft-sealing gas storage container 60, and is used to transport the carbon dioxide gas exhausted from the blade-type rotary cylinder 532 to the shaft-sealing gas storage container 60. Since the high-pressure carbon dioxide gas input from the liquid storage unit 30 to the blade-type rotary cylinder 532 is the circulating working fluid of the carbon dioxide energy storage system 100, this part of the high-pressure carbon dioxide gas drives the blade-type rotary cylinder 532 to rotate and is then recovered to the shaft-sealing gas storage container 60, and can subsequently be returned to the circulation pipeline of the energy storage system through the shaft-sealing gas pipeline, thereby avoiding the loss of the circulating working fluid.

[0067] Based on the lubricating oil supply device 50 and its corresponding carbon dioxide energy storage system 100 provided in the above embodiment, the embodiment of the present invention further provides a control method of the carbon dioxide energy storage system 100. The control method includes:

[0068] (a) When the energy storage assembly 20 is in the energy storage operating condition and the energy release assembly is in the cranking operating condition, the first oil supply unit 51 is controlled to provide lubricating oil to the energy storage assembly 20 , and the second oil supply unit 52 is controlled to provide lubricating oil to the energy release assembly 40 .

[0069] Specifically, when the carbon dioxide energy storage system 100 operates normally, and the energy storage assembly 20 is in the energy storage operating condition and the energy release assembly 20 is in the cranking operating condition: in the first oil supply unit 51, the first driving mechanism 51c drives the first oil pump 51a to start, controls the first oil supply valve 514 to open, and controls the second oil supply valve 515 to close, and the first oil quantity of lubricating oil provided by the first oil pump 51a is delivered to the compressor 21 in the energy storage assembly 20 via the first oil supply main line 511 and the first oil supply branch line 512. In the second oil supply unit 52, the second driving mechanism 52c drives the second oil pump 52a to start, controls the third oil supply valve 524 to close, and controls the fourth oil supply valve 525 to open, and the second oil quantity of lubricating oil provided by the second oil pump 52a is delivered to the turbine 43 in the energy release assembly 40 via the second oil supply main line 521 and the fourth oil supply branch line 523.

[0070] (b) When the energy release assembly 40 is in the energy release operating condition and the energy storage assembly 20 is in the cranking operating condition, the first oil supply unit 51 is controlled to provide lubricating oil to the energy release assembly 40 , and the second oil supply unit 52 is controlled to provide lubricating oil to the energy storage assembly 20 .

[0071] Specifically, when the carbon dioxide energy storage system 100 operates normally, and the energy release component 40 is in the energy release operating condition and the energy storage component 20 is in the cranking operating condition: in the first oil supply unit 51, the first driving mechanism 51c drives the first oil pump 51a to start, controls the first oil supply valve 514 to be closed, and controls the second oil supply valve 515 to be opened, and the first oil quantity of lubricating oil provided by the first oil pump 51a is delivered to the turbine 43 in the energy release component 40 via the first oil supply main line 511 and the second oil supply branch line 513. In the second oil supply unit 52, the second driving mechanism 52c drives the second oil pump 52a to start, controls the third oil supply valve 524 to be opened, and controls the fourth oil supply valve 525 to be closed, and the second oil quantity of lubricating oil provided by the second oil pump 52a is delivered to the compressor 21 in the energy storage component 20 via the second oil supply main line 521 and the third oil supply branch line 522.

[0072] (c) When the energy storage assembly 20 and the energy release assembly 40 are both in the cranking operation state, the second oil supply unit 52 is controlled to supply lubricating oil to the energy storage assembly 20 and the energy release assembly 40 respectively.

[0073] Specifically, when the carbon dioxide energy storage system 100 operates normally, and the energy storage component 20 and the energy release component 40 are both in the cranking operation state, the first oil supply unit 51 is closed, and in the second oil supply unit 52, the second drive mechanism 52c drives the second oil pump 52a to start, and the third oil supply valve 524 and the fourth oil supply valve 525 are controlled to be open, and the second amount of lubricating oil provided by the second oil pump 52a is input into the second oil supply main line 521, and then transported to the compressor 21 in the energy storage component 20 by the third oil supply branch line 522, and transported to the turbine 43 in the energy release component 40 by the fourth oil supply branch line 523.

[0074] (d) When the carbon dioxide energy storage system 100 fails and the first oil supply unit 51 and the second oil supply unit 52 are unable to supply oil, the third oil supply unit 53 is started to provide emergency lubricating oil to the energy storage assembly 20 and the energy release assembly 40 at the same time.

[0075] Specifically, when the carbon dioxide energy storage system 100 fails and the first oil supply unit 51 and the second oil supply unit 52 cannot supply oil, the first oil supply valve 514 and the second oil supply valve 515 are controlled to be opened, and in the third oil supply unit 53, the energized normally closed solenoid valve 534 is controlled to be de-energized and opened, and the high-pressure carbon dioxide gas in the liquid storage unit 30 is input into the vane-type rotary cylinder 532, driving the vane-type rotary cylinder 532 to rotate, thereby driving the third oil pump 53a to provide emergency lubricating oil, which is input into the first oil supply branch 512 through the third oil supply main line 531, and then transported to the compressor 21 in the energy storage component 20 through the first oil supply branch 512, and transported to the turbine 43 in the energy release component 40 through the second oil supply branch 513, until all the units of the energy storage system are shut down.

[0076] In summary, the lubricating oil supply device, carbon dioxide energy storage system and control method thereof provided by the above embodiments of the present invention are provided by arranging a first oil supply unit and a second oil supply unit which can be independently controlled respectively in the lubricating oil supply device: when the energy storage component or the energy release component is in the starting operation condition, the first oil supply unit with a larger power is controlled to provide a larger amount of lubricating oil required to meet the equipment starting operation condition; when the energy storage component or the energy release component is in the cranking operation condition, the second oil supply unit with a smaller power is controlled to provide a smaller amount of lubricating oil required to meet the equipment cranking operation condition. In a preferred solution, the high-pressure carbon dioxide gas in the energy storage system is used as a power source to drive the second oil supply unit to supply accidental lubricating oil, thereby improving the accident response speed. Therefore, this solution not only reduces the energy consumption of the system, reduces the loss of lubricating oil, reduces costs, but also improves the safety of system operation.

[0077] The above is only a specific implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A control method for a carbon dioxide energy storage system, characterized in that: The carbon dioxide energy storage system includes an energy storage component and an energy release component, and the control method includes: When the energy storage component is in an energy storage operating condition and the energy release component is in a cranking operating condition, controlling the first oil supply unit to supply a first amount of lubricating oil to the energy storage component, and controlling the second oil supply unit to supply a second amount of lubricating oil to the energy release component; When the energy release component is in an energy release operating condition and the energy storage component is in a cranking operating condition, controlling the first oil supply unit to supply a first amount of lubricating oil to the energy release component, and controlling the second oil supply unit to supply a second amount of lubricating oil to the energy storage component; When the energy storage component and the energy release component are both in a cranking operation state, controlling the second oil supply unit to supply a second amount of lubricating oil to the energy storage component and the energy release component respectively; When the carbon dioxide energy storage system fails and the first oil supply unit and the second oil supply unit are unable to supply oil, the third oil supply unit is started to simultaneously supply emergency lubricating oil to the energy storage component and the energy release component; Wherein, the second oil amount is smaller than the first oil amount.

2. A lubricating oil supply device, characterized in that: The lubricating oil supply device is applied to the control method of the carbon dioxide energy storage system as claimed in claim 1 to supply oil to the energy storage component and the energy release component; the lubricating oil supply device comprises a first oil supply unit, a second oil supply unit and a third oil supply unit respectively connected between the lubricating oil tank and the energy storage component and the energy release component; the first oil supply unit is configured to be driven by a first power to provide a first amount of lubricating oil to the energy storage component and the energy release component; the second oil supply unit is configured to be driven by a second power to provide a second amount of lubricating oil to the energy storage component and the energy release component; the third oil supply unit is configured to provide emergency lubricating oil to the energy storage component and the energy release component; The second power is less than the first power.

3. The lubricating oil supply device according to claim 2, characterized in that: The first oil amount is 2 to 3 times the second oil amount.

4. The lubricating oil supply device according to claim 2, characterized in that: The first oil supply unit includes a first oil pump, a first pipeline and a first driving mechanism, wherein the first oil pump is disposed in the lubricating oil tank, the first oil pump is connected to the energy storage component and the energy release component through the first pipeline, and the first driving mechanism is configured to drive the first oil pump with the first power to provide the first oil volume; and / or, The second oil supply unit comprises a second oil pump, a second pipeline and a second driving mechanism, the second oil pump is arranged in the lubricating oil tank, the second oil pump is connected to the energy storage component and the energy release component through the second pipeline, and the second driving mechanism is configured to drive the second oil pump with the second power to provide the second oil quantity; and / or, The third oil supply unit includes a third oil pump, a third pipeline and a third driving mechanism. The third oil pump is arranged in the lubricating oil tank. The third oil pump is connected to the energy storage component and the energy release component through the third pipeline. The third driving mechanism is used to drive the third oil pump to provide the emergency lubricating oil.

5. The lubricating oil supply device according to claim 4, characterized in that: The first pipeline includes a first oil supply main pipeline, a first oil supply branch pipeline and a second oil supply branch pipeline, wherein a first end of the first oil supply main pipeline is connected to an output end of the first oil pump, a first end of the first oil supply branch pipeline and a first end of the second oil supply branch pipeline are respectively connected to a second end of the first oil supply main pipeline, a second end of the first oil supply branch pipeline is connected to the energy storage component, and a second end of the second oil supply branch pipeline is connected to the energy release component, a first oil supply valve is provided on the first oil supply branch pipeline, and a second oil supply valve is provided on the second oil supply branch pipeline; The second pipeline includes a second oil supply main line, a third oil supply branch line and a fourth oil supply branch line, the first end of the second oil supply main line is connected to the output end of the second oil pump, the first end of the third oil supply branch line and the first end of the fourth oil supply branch line are respectively connected to the second end of the second oil supply main line, the second end of the third oil supply branch line is connected to the energy storage component, the second end of the fourth oil supply branch line is connected to the energy release component, the third oil supply branch line is provided with a third oil supply valve, and the fourth oil supply branch line is provided with a fourth oil supply valve; The third pipeline includes a third oil supply main line, a first end of the third oil supply main line is connected to an output end of the third oil pump, and a second end of the third oil supply main line is connected to the first oil supply main line.

6. The lubricating oil supply device according to claim 4, characterized in that: The first driving mechanism and the second driving mechanism are driving motors respectively.

7. The lubricating oil supply device according to any one of claims 4 to 6, characterized in that: The carbon dioxide energy storage system further includes a liquid storage unit, which is used to store liquid carbon dioxide and contains high-pressure carbon dioxide gas; the third driving mechanism includes: A vane type rotary cylinder, connected to the third oil pump, and used for rotationally driving the third oil pump; A gas transmission pipeline, connected between the liquid storage unit and the blade type rotary cylinder, for transmitting the high-pressure carbon dioxide gas in the liquid storage unit to the blade type rotary cylinder to drive the blade type rotary cylinder to rotate; The energized normally closed solenoid valve is connected to the gas transmission pipeline.

8. The lubricating oil supply device according to claim 7, characterized in that: The carbon dioxide energy storage system also includes a shaft sealing gas storage container, which is used to store shaft sealing gas; the third driving mechanism also includes an exhaust pipeline, which is connected between the blade-type rotary cylinder and the shaft sealing gas storage container, and is used to transport the carbon dioxide gas discharged from the blade-type rotary cylinder to the shaft sealing gas storage container.

9. The lubricating oil supply device according to claim 7, characterized in that: A gas pressure regulating valve is arranged on the gas transmission pipeline.

10. A carbon dioxide energy storage system, characterized in that: It comprises an air storage unit, an energy storage assembly, a liquid storage unit and an energy release assembly which are sequentially connected in a closed loop, and also comprises a lubricating oil supply device as described in any one of claims 2-9.

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