A power grid power regulation system and a power grid power regulation method

Abstract

This specification discloses a power grid power regulation system and a power grid power regulation method, which relate to the field of energy storage technologies. Based on nitrogen gas tanks, compressors, water-nitrogen coexistence tanks, motors, compressors, pumps, water-nitrogen coexistence tanks, first water turbines, first generators, water tanks, motors, and pumps, the present invention forms a pumped storage device including a nitrogen pressure regulation module, a pumped storage module, and a water release energy release module. When the power grid is in a non-peak regulation state and a low load state, the power grid powers the charging piles, and the pumped storage module performs a pumping energy storage process to obtain and store energy from the power grid. When the power grid is in a peak regulation state or a high load state, the power supply from the power grid to the charging piles is cut off, and the water release energy release module performs a water release energy release process to supply power to the charging piles using the pumped storage device. The present invention reduces the impact of the charging station on the power grid through corresponding regulation in different states and improves the stability of the power grid.

Description

Technical Field

[0001] This application relates to the technical field of energy storage, and particularly to a power grid power regulation system. Background Art

[0002] Currently, the new energy vehicle industry in China has developed rapidly, and the national electric vehicle ownership has increased rapidly. Due to the continuous improvement of people's requirements for travel convenience, the charging power has gradually increased to meet the needs of large-capacity batteries and fast charging. However, when multiple high-power vehicle charging piles operate simultaneously, the peak power of the charging station will increase sharply, which will impact the power grid and affect the stability of the power grid. At the same time, the power of the charging station changes with the number of charging vehicles, and the power volatility and uncertainty are high, further deepening the impact on the power grid.

[0003] Energy storage technology, as an important measure to regulate the balance of the power system and improve the stability of the power grid, is a key research direction in the energy field. The current energy storage technologies mainly include pumped-storage energy storage, compressed air energy storage, electromagnetic energy storage, and electrochemical energy storage, etc. Among them, electromagnetic energy storage and electrochemical energy storage are limited by scale levels and economic costs, while pumped-storage energy storage requires the construction of an upper reservoir and a lower reservoir to achieve the conversion of electrical energy into gravitational potential energy, so it has high requirements for terrain and occupies a large area. Compressed air energy storage requires a large-volume gas storage tank due to the low gas density. For the above reasons, both of them cannot be deployed near fast charging stations.

[0004] It can be seen that the current energy storage technology cannot be directly applied to the charging station scenario, and the charging station has a high impact on the power grid, resulting in poor stability of the power grid under the impact. Summary of the Invention

[0005] A power grid power regulation method of a power grid power regulation system provided in an embodiment of this specification is used to partially solve the problems existing in the prior art.

[0006] The embodiments of this specification adopt the following technical solutions:

[0007] This specification provides a power grid power regulation system, including:

[0008] A pumped-storage energy storage device, including a nitrogen pressure regulating module, a pumped-storage energy storage module, and a water release and energy release module;

[0009] The nitrogen pressure regulating module includes a nitrogen tank, a compressor, a water-nitrogen coexistence tank, and an electric motor. Among them, the nitrogen tank, the compressor, and the water-nitrogen coexistence tank are connected in sequence, and the electric motor is connected to the compressor for driving the compressor to pressurize the nitrogen in the nitrogen tank and send it into the water-nitrogen coexistence tank;

[0010] The pumped - storage energy storage module includes a water - nitrogen co - existence tank, a pump, a water tank, and a motor. Among them, the water tank, the pump, and the water - nitrogen co - existence tank are connected in sequence, and the motor is connected to the pump to drive the pump to pressurize and transport the liquid in the water tank to the water - nitrogen co - existence tank;

[0011] The water - releasing and energy - releasing module includes a water - nitrogen co - existence tank, a first water turbine, a first generator, and a water tank. Among them, the water - nitrogen co - existence tank, the first water turbine, and the water tank are connected in sequence, and the first generator is connected to the first water turbine;

[0012] The data acquisition module is electrically connected to the pumped - storage energy storage device, the power grid, and the charging pile respectively;

[0013] The regulation and decision - making module is electrically connected to the data acquisition module and the pumped - storage energy storage device respectively;

[0014] When the data acquisition module simultaneously obtains the state information that the energy storage capacity of the pumped - storage energy storage device is less than the maximum energy storage capacity, the power grid is in a non - peak - shaving state, and the power grid is in a low - load state, a pumped - storage energy storage instruction is sent to the pumped - storage energy storage module through the regulation and decision - making module. The pumped - storage energy storage module pressurizes and sends the liquid in the water tank into the water - nitrogen co - existence tank through the pump; The charging pile is powered by the power grid;

[0015] When the data acquisition module obtains the state information that the power grid is in a peak - shaving state or a high - load state, and at the same time the energy storage capacity of the pumped - storage energy storage device is greater than the minimum energy - releasing capacity, the power supply from the power grid to the charging pile is cut off; And a water - releasing and energy - releasing instruction is sent to the water - releasing and energy - releasing module through the regulation and decision - making module. The water - releasing and energy - releasing module controls the water - nitrogen co - existence tank to release the liquid and enter the first water turbine to drive the first generator to generate electricity, and the first generator supplies power to the charging pile.

[0016] Optionally, the pumped - storage energy storage device further includes: a pressure - stabilizing tank, a first control valve, a second control valve, a third control valve, a fourth control valve, and a fifth control valve;

[0017] The water - nitrogen co - existence tank includes a first inlet, a second inlet, and a first outlet;

[0018] The outlet of the nitrogen tank is connected to the inlet of the compressor through the second control valve, the outlet of the compressor is connected to the inlet of the pressure - stabilizing tank, the first outlet of the pressure - stabilizing tank is connected to the first inlet of the water - nitrogen co - existence tank through the third control valve, and the second outlet of the pressure - stabilizing tank is connected to the inlet of the nitrogen tank through the first control valve;

[0019] The first outlet of the water - nitrogen co - existence tank is connected to the inlet of the first water turbine through the fourth control valve, the outlet of the first water turbine is connected to the first inlet of the water tank, and the first water turbine is connected to the first generator;

[0020] The first outlet of the water tank is connected to the inlet of the pump through a fifth control valve, and the outlet of the pump is connected to the second inlet of the water-nitrogen coexistence tank;

[0021] The motor is connected to the compressor through a first coupling, and the motor is connected to the pump through a second coupling.

[0022] Optionally, the pumped-storage device further includes: a sixth control valve, a seventh control valve, an eighth control valve, a second water turbine, a third coupling, and a fourth coupling;

[0023] The first outlet of the water-nitrogen coexistence tank is divided into two paths. The first path is connected to the inlet of the first water turbine through a fourth control valve, and the second path converges with the outlet of the first water turbine through the eighth control valve;

[0024] After convergence, it is further divided into two branches. The first branch is connected to the inlet of the second water turbine through a sixth control valve, and the second branch is connected to the outlet of the second water turbine through a seventh control valve and then enters the first inlet of the water tank;

[0025] The first generator is connected to the first water turbine through a third coupling, and the first generator is connected to the second water turbine through a fourth coupling;

[0026] The first water turbine and the second water turbine are arranged in series or in parallel.

[0027] Optionally, the pumped-storage device further includes: a ninth control valve, a third water turbine, and a second generator; the water-nitrogen coexistence tank further includes a second outlet;

[0028] The second outlet of the water-nitrogen coexistence tank is connected to the inlet of the third water turbine through a ninth control valve, and the outlet of the third water turbine is connected to the second inlet of the water tank.

[0029] Optionally, the water-nitrogen coexistence tank includes a hydraulic pump, a hydraulic rod, a partition plate, and a tank body; the regulation decision-making module is connected to the hydraulic pump;

[0030] The regulation decision-making module drives the hydraulic rod through the hydraulic pump to generate pressure or tension on the partition plate, adjusting the pressure of the water in the water-nitrogen coexistence tank.

[0031] Optionally, the partition plate is a variable-resistance partition plate, and the output power of the pumped-storage device is adjusted by adjusting the friction between the partition plate and the tank body;

[0032] When the friction increases, the movement speed of the partition plate decreases, the water outlet pressure of the water-nitrogen coexistence tank decreases, and the output power of the pumped-storage device decreases;

[0033] When the friction decreases, the movement speed of the partition plate increases, the water outlet pressure of the water-nitrogen coexistence tank increases, and the output power of the pumped-storage device increases.

[0034] Optionally, the nitrogen gas tank is also used to supplement nitrogen to the water-nitrogen coexistence tank through a compressor as needed; alternatively, the first control valve is also used to open as needed to allow the nitrogen gas in the pressure stabilizing tank to flow back to the nitrogen gas tank, so as to reduce the nitrogen gas pressure in the water-nitrogen coexistence tank and regulate the energy storage capacity of the pumped storage device.

[0035] This specification provides a power grid regulation method based on a power grid power regulation system, including:

[0036] Initialize the states of all valves in the power grid power regulation system, and send nitrogen gas into the water-nitrogen coexistence tank through the nitrogen pressure regulation module according to the preset maximum energy storage capacity until the preset pressure corresponding to the maximum energy storage capacity is reached;

[0037] The data acquisition module continuously acquires the load status of the power grid and the energy storage capacity of the pumped storage device under the operating power of the charging pile;

[0038] When the power grid is in a low-load and non-peak shaving state, the power grid supplies power to the charging pile; at the same time, if the pumped storage device has not reached the maximum energy storage capacity, a pumping energy storage instruction is sent to the pumped storage module through the regulation decision module, so that the pumped storage device executes the pumping energy storage process to obtain and store energy from the power grid;

[0039] When the power grid is in a high-load or peak shaving state, and the pumped storage device is greater than the minimum energy release capacity, the charging pile is disconnected from the power grid, and a water release energy storage instruction is sent to the pumped storage module through the regulation decision module, so that the pumped storage device executes the water release energy storage process to supply power to the charging pile.

[0040] The above at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0041] The present invention forms a nitrogen pressure regulation module based on a nitrogen gas tank, a compressor, a water-nitrogen coexistence tank, and a motor, forms a pumped storage module and a water release energy storage module based on the water-nitrogen coexistence tank, a first water turbine, a first generator, a water tank, a pump, and a motor, and forms a pumped storage device with the nitrogen pressure regulation module, the pumped storage module, and the water release energy storage module. The maximum storage capacity of the pumped storage device is set through the nitrogen pressure regulation module. When the power grid is in a non-peak shaving state and a low-load state, the power grid supplies power to the charging pile, and the pumped storage module executes the pumping energy storage process to obtain and store energy from the power grid. When the power grid is in a peak shaving state or a high-load state, the power supply from the power grid to the charging pile is cut off, and the water release energy storage module executes the water release energy storage process to supply power to the charging pile using the pumped storage device. The present invention reduces the impact of the charging station on the power grid through corresponding regulation in different states and improves the stability of the power grid. Description of the Drawings

[0042] The accompanying drawings described herein are used to provide a further understanding of the present application and form a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation of the present application. In the drawings:

[0043] Figure 1 A schematic diagram of a power grid power regulation system provided in this specification;

[0044] Figure 2 A schematic diagram of a pumped storage device provided in this specification;

[0045] Figure 3 A schematic diagram of a water-nitrogen coexistence tank provided in this specification;

[0046] Figure 4 A power grid power regulation method based on the power grid power regulation system provided in this specification;

[0047] Figure 5 A power grid power regulation method based on an optimized power grid power regulation system provided in this specification;

[0048] Figure 6 A power grid power stability regulation method based on the power grid power regulation system provided in this specification. Detailed implementation manners

[0049] To make the objectives, technical solutions, and advantages of this specification clearer, the technical solutions of the present application will be clearly and completely described below in conjunction with the specific embodiments of this specification and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in this specification, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present application.

[0050] The following will detail the technical solutions provided by each embodiment of the present application in conjunction with the drawings.

[0051] Current energy storage technologies mainly include pumped storage, compressed gas energy storage, electromagnetic energy storage, and electrochemical energy storage, etc. Among them, electromagnetic energy storage and electrochemical energy storage are limited by scale levels and economic costs, while pumped storage and compressed air energy storage are restricted by terrain and cannot be deployed near fast charging stations.

[0052] Therefore, there is an urgent need to configure suitable energy storage devices and their operation methods for high-power power consumption systems such as charging stations to stabilize input and output, reduce the impact on the power grid, and improve power grid stability.

[0053] Figure 1 A schematic diagram of a power grid power regulation system in this specification, consisting of Figure 1It can be seen that it includes: a data acquisition module, a regulation and decision-making module, a nitrogen pressure regulation module, a pumped storage module, and a water release and energy release module. Among them, the nitrogen pressure regulation module, the pumped storage module, and the water release and energy release module form a pumped storage device. Figure 1 The power grid, a fast charging pile, and an electric vehicle are also shown. The electric vehicle is charged through the fast charging pile. On the one hand, the fast charging pile is connected to the power grid and is powered by the power grid when needed. On the other hand, it is connected to the pumped storage device and can be powered by the pumped storage device when needed.

[0054] Figure 2 This is a schematic diagram of a pumped storage device in this specification. In one or more embodiments of this specification, the pumped storage device includes a nitrogen pressure regulation module, a pumped storage module, and a water release and energy release module.

[0055] The nitrogen pressure regulation module includes a nitrogen tank 1, a compressor 2, a water-nitrogen coexistence tank 4, and a motor 9. Among them, the nitrogen tank 1, the compressor 2, and the water-nitrogen coexistence tank 4 are connected in sequence. The motor 9 is connected to the compressor 2 and is used to drive the compressor 2 to pressurize the nitrogen in the nitrogen tank 1 and send it into the water-nitrogen coexistence tank 4 until the preset pressure is reached.

[0056] The pumped storage module includes a water-nitrogen coexistence tank 4, a pump 8, a water tank 12, and a motor 9. Among them, the water tank 12, the pump 8, and the water-nitrogen coexistence tank 4 are connected in sequence. The motor 9 is connected to the pump 8 and is used to drive the pump 8 to pressurize and transport the liquid in the water tank 12 to the water-nitrogen coexistence tank 4. The motor 9 is powered by the power grid.

[0057] The water release and energy release module includes a water-nitrogen coexistence tank 4, a first water turbine 5, a first generator 10, and a water tank 12. Among them, the water-nitrogen coexistence tank 4, the first water turbine 5, and the water tank 12 are connected in sequence. The first generator 10 is connected to the first water turbine 5.

[0058] The data acquisition module is electrically connected to the pumped storage device, the power grid, and the charging pile (or fast charging pile) of the charging station respectively. The regulation and decision-making module is electrically connected to the data acquisition module and the pumped storage device respectively.

[0059] When the data acquisition module simultaneously obtains the state information that the energy storage capacity of the pumped storage device is less than the maximum energy storage capacity, the power grid is in a non-peak regulation state, and the power grid is in a low-load state, it sends a pumped storage instruction to the pumped storage module through the regulation and decision-making module. The pumped storage module pressurizes and sends the liquid in the water tank 12 into the water-nitrogen coexistence tank 4 through the pump 8. At this time, the charging pile is powered by the power grid.

[0060] When the data acquisition module obtains the state information that the power grid is in the peak shaving state or the high load state, and at the same time the energy storage capacity of the pumped storage device is greater than the minimum energy release capacity, the power supply from the power grid to the charging pile is cut off, and a water release energy instruction is sent to the water release energy module through the regulation decision module. The water release energy module controls the water-nitrogen coexistence tank 4 to release liquid and enter the first water turbine 5 to drive the first generator 10 to generate electricity, and the first generator 10 supplies power to the charging piles of the charging station. That is, at this time, the charging piles are powered by the pumped storage device.

[0061] In addition, in one or more embodiments of the present specification, the pumped storage device may further include: a pressure stabilizing tank 3, a first control valve 13, a second control valve 14, a third control valve 15, a fourth control valve 17, and a fifth control valve 20.

[0062] The water-nitrogen coexistence tank 4 may include a first inlet 201, a second inlet 202, and a first outlet 203, as Figure 3 shown, Figure 3 which is a schematic diagram of a water-nitrogen coexistence tank in this specification.

[0063] The outlet of the nitrogen tank 1 is connected to the inlet of the compressor 2 through the second control valve 14, the outlet of the compressor 2 is connected to the inlet of the pressure stabilizing tank 3, the first outlet of the pressure stabilizing tank 3 is connected to the first inlet 201 of the water-nitrogen coexistence tank 4 through the third control valve 15, and the second outlet of the pressure stabilizing tank 3 is connected to the inlet of the nitrogen tank 1 through the first control valve 13.

[0064] The first outlet 203 of the water-nitrogen coexistence tank 4 is connected to the inlet of the first water turbine 5 through the fourth control valve 17, the outlet of the first water turbine 5 is connected to the first inlet of the water tank 12, and the first water turbine 5 is connected to the first generator 10.

[0065] The first outlet of the water tank 12 is connected to the inlet of the pump 8 through the fifth control valve 20, and the outlet of the pump 8 is connected to the second inlet 202 of the water-nitrogen coexistence tank 4.

[0066] The motor 9 is connected to the compressor 2 through the first coupling 22, and the motor 9 is connected to the pump 8 through the second coupling 23.

[0067] Based on this, the present specification also provides a power grid power regulation method based on a power grid power regulation system, as Figure 4 shown, which specifically includes the following steps:

[0068] S201: The data acquisition module obtains load peak shaving information from the power grid, obtains output power information from the charging piles, obtains energy storage capacity information from the pumped storage device, and transmits the above information to the regulation decision module.

[0069] Of course, before the normal operation of the pumped-storage energy storage device, it is necessary to initialize the states of all valves in the grid power regulation system. All valves should be in the closed state under the initial built state.

[0070] It is also necessary to initialize the nitrogen pressure regulation module, that is, according to the preset maximum energy storage capacity, send nitrogen into the water-nitrogen coexistence tank through the nitrogen pressure regulation module until the preset pressure corresponding to the maximum energy storage capacity is reached. Specifically, the second control valve 14 and the third control valve 15 can be opened, the first coupling 22 can be closed, the motor 9 rotates to drive the compressor 2 to work, and the nitrogen in the nitrogen tank 1 is pressurized and enters the pressure stabilizing tank and the water-nitrogen coexistence tank 4. When the preset pressure is reached, the motor 9, the compressor 2, and the second control valve 14 are closed, the first coupling 22 is disconnected, and the third control valve 15 remains open. Thus, the initialization of the nitrogen pressure regulation module is completed.

[0071] S202: The regulation decision-making module receives the information from the data acquisition module. First, it judges the grid information. Currently, the load is lower than the preset value, the grid is in a low-load state, and the peak shaving information is judged to be in a non-peak shaving state. Secondly, it judges the pumped-storage energy storage device information. At this time, the energy storage capacity is less than the maximum energy storage capacity, and it is judged that there is still room for the energy storage capacity. Finally, it judges the charging pile information. The charging power of the vehicle is less than the high-power critical value, and it is judged to be in a non-high-power output working condition.

[0072] S203: Based on the above information, the regulation decision-making module issues the following instructions: The pumping energy storage module of the pumped-storage energy storage device starts to work, obtains electric energy from the grid, enters the energy storage state, and the water release energy module stops working.

[0073] S204: When the information processed by the regulation decision-making module is that the grid load is greater than the preset value or the peak shaving state starts or the fast charging power is greater than the high-power critical value or the energy storage capacity is equal to the maximum energy storage capacity, a stop work instruction is sent to the pumping energy storage module.

[0074] At this time, the charging pile is directly connected to the grid, and the electric energy from the grid is used to charge the electric vehicle. When the pumped-storage energy storage device has not reached the maximum capacity, the pumping energy storage module of the pumped-storage energy storage device starts to work: open the fifth control valve 20, close the second coupling 23, and other valves and couplings are in the fully closed state. The motor 9 rotates to drive the pump 8 to pressurize the normal temperature and pressure water in the water tank 12 and store it in the water-nitrogen coexistence tank 4.

[0075] When the information processed by the regulation decision-making module is that the grid load is greater than the preset value or the peak shaving state starts or the fast charging power is greater than the high-power critical value or the energy storage capacity is equal to the maximum energy storage capacity, the regulation decision-making module issues a shutdown instruction, closes the motor 9, the pump 8, and the fifth control valve 20, and disconnects the second coupling 23 to complete the energy storage stage.

[0076] Further, in one or more embodiments of this specification, the pumped storage device may further include: a sixth control valve 18, a seventh control valve 19, an eighth control valve 16, a second water turbine 6, a third coupling 24, and a fourth coupling 25.

[0077] The first outlet 203 of the water-nitrogen coexistence tank 4 is divided into two paths. The first path is connected to the inlet of the first water turbine 5 through the fourth control valve 17, and the second path converges with the outlet of the first water turbine 5 through the eighth control valve 16.

[0078] After convergence, it is further divided into two branches. The first branch is connected to the inlet of the second water turbine 6 through the sixth control valve 18, and the second branch converges with the outlet of the second water turbine 6 through the seventh control valve 19. After convergence, it is connected to the first inlet of the water tank 12.

[0079] The first generator 10 is connected to the first water turbine 5 through the third coupling 24, and the first generator 10 is connected to the second water turbine 6 through the fourth coupling 25.

[0080] The first water turbine 5 and the second water turbine 6 are arranged in series or in parallel. When the first water turbine 5 and the second water turbine 6 are arranged in series, the series arrangement of the first water turbine 5 and the second water turbine 6 facilitates the separate adjustment of the guide vane angles of the two water turbines to improve the energy utilization rate. When the first water turbine 5 and the second water turbine 6 are arranged in parallel, the overall power of the device can be increased without affecting the operation of the first water turbine 5 and the second water turbine 6, achieving a higher output power. Multiple pipes and control valves can also be arranged around the first water turbine 5 and the second water turbine 6, which can achieve the disconnection of any water turbine to adjust the system output power.

[0081] Furthermore, in one or more embodiments of this specification, the pumped storage device further includes: a ninth control valve 21, a third water turbine 7, and a second generator 11; the water-nitrogen coexistence tank 4 further includes a second outlet 204;

[0082] The second outlet 204 of the water-nitrogen coexistence tank 4 is connected to the inlet of the third water turbine 7 through the ninth control valve 21, and the outlet of the third water turbine 7 is connected to the second inlet of the water tank 12.

[0083] In addition, in one or more embodiments of this specification, the water-nitrogen coexistence tank 4 may further include a hydraulic pump 205, a hydraulic rod 206, a partition plate 207, and a tank body 208; the regulation and decision-making module is connected to the hydraulic pump 205.

[0084] The regulation and decision-making module drives the hydraulic rod 206 through the hydraulic pump 205 to generate pressure or tension on the partition plate 207, and adjusts the pressure of the water in the water-nitrogen coexistence tank 4.

[0085] Based on this, this specification also provides a grid power regulation method based on an optimized grid power regulation system, as Figure 5 shown, which specifically includes the following steps:

[0086] S301: The data acquisition module obtains load peak shaving information from the grid, output power information from the charging pile, and energy storage capacity information from the pumped storage device, and transmits the above information to the regulation and control decision-making module.

[0087] S302: After receiving the information from the data acquisition module, the regulation and control decision-making module first judges the grid information. Currently, the load is higher than the preset value, the grid is in a high-load state, and the peak shaving information is judged to be in a non-peak shaving state. Secondly, it judges the information of the pumped storage device. At this time, the energy storage capacity is greater than the minimum energy release capacity, and it is judged that energy can be released. Finally, it judges the information of the charging pile. The charging power of the vehicle is greater than the high-power critical value, and it is judged to be in a high-power output working condition.

[0088] S303: Based on the above information, the regulation and control decision-making module issues the following instructions: The pumping and energy release module of the pumped storage device starts to work, stops obtaining electric energy from the grid, provides electric energy to the charging pile, enters the energy release state, and the pumping energy storage module stops working.

[0089] At this time, the charging pile is disconnected from the grid. According to the energy release instruction issued by the regulation and control decision-making module, the water release and energy release module of the pumped storage device executes the first gear load mode: open the fourth control valve 17 and the seventh control valve 19, and close the third coupling 24. The other valves and couplings remain closed. The liquid in the water-nitrogen coexistence tank 4 flows out, enters the first water turbine 5, drives the first generator 10 to rotate and generate electricity, and inputs the generated electric energy into the charging pile to meet the needs of the fast charging power.

[0090] When the power demand of the charging pile further increases, the regulation and control decision-making module issues a load increase instruction. The hydraulic pump 205 starts to boost pressure, drives the hydraulic rod 206 to transmit the pressure to the partition plate 207, the pressure of the water in the tank increases, and the device power increases. When the second gear load critical value is reached, the water release and energy release module executes the second gear load mode, the hydraulic pump 205 stops working, the pressure in the water-nitrogen coexistence tank 4 gradually recovers, and on this basis, the seventh control valve 19 is closed, the sixth control valve 18 is opened, the fourth coupling 25 is closed, and the second water turbine 6 is put into operation. The first water turbine 5 and the second water turbine 6 jointly drive the first generator 10 to generate electricity, and the electric energy is input into the charging pile to meet the needs of the increasing charging load.

[0091] When the power of the charging pile needs to be further increased, the regulation decision-making module issues a parallel load-increasing command. The hydraulic pump 205 starts to increase the pressure, driving the hydraulic rod 206 to transfer the pressure to the partition plate 207. The pressure of the water in the tank increases, and the power of the device increases. When the critical value of the third gear load is reached, the water release energy module executes the third gear load mode. The hydraulic pump 205 stops working, and the pressure in the water-nitrogen coexistence tank 4 gradually recovers. On this basis, the ninth control valve 21 is opened, and the third water turbine 7 is put into operation. The high-pressure water in the water-nitrogen coexistence tank 4 enters the third water turbine 7 to do work, driving the second generator 11 to generate electricity. At this time, all three water turbines are put into operation, and the two generators generate electricity simultaneously, and the electric energy is input into the charging pile. At this time, the maximum output power of the pumped-storage device reaches the maximum output power of the charging pile.

[0092] S304: When the information processed by the regulation decision-making module is that the grid load is less than the preset value, or the fast charging power is less than the high-power critical value, or the energy storage capacity is less than the minimum energy release capacity, a stop work command is sent to the water release energy module.

[0093] This can be achieved by closing the fourth control valve 17, the sixth control valve 18, and the ninth control valve 21, and disconnecting the third coupling 24 and the fourth coupling 25.

[0094] Based on the grid power regulation system in one or more of the above embodiments, this specification also provides a grid power stable regulation method based on the grid power regulation system, as Figure 6 shown, which specifically includes the following steps:

[0095] S401: The data acquisition module obtains the load peak shaving information from the grid, the output power information from the charging pile, and the energy storage capacity information from the pumped-storage device, and transfers the above information to the regulation decision-making module.

[0096] S402: After receiving the information from the data acquisition module, the regulation decision-making module first judges the grid information. Currently, the load is higher than the preset value, the grid is in a high-load state, and the peak shaving information is judged to be in the peak shaving state. Secondly, it judges the information of the pumped-storage device. At this time, the energy storage capacity is greater than the minimum energy release capacity, and it is judged that energy can be released. Finally, it judges the information of the charging pile. The charging power of the vehicle is greater than the high-power critical value, and it is judged to be in the high-power output working condition.

[0097] S403: Based on the above information, the regulation decision-making module issues the following commands: The pumped-storage device water release energy module starts to work, provides electric energy to the grid, provides electric energy to the charging pile, enters the energy release state, and the pumped-storage module stops working.

[0098] On the premise of ensuring that the charging pile outputs stably at the required power, according to the need of the power grid's peak shaving load, the pumped storage device can switch between the first gear, the second gear, and the third gear of load according to different load instructions issued by the regulation decision-making module. The regulation decision-making module can control the hydraulic pump 205 in the water-nitrogen coexistence tank 4 to drive the hydraulic rod 206 according to the collected power grid and charging pile load information, so that the hydraulic rod 206 generates pressure or tension on the partition plate 207, thereby realizing the change of the water pressure in the tank and achieving power matching under different loads, so as to achieve the purpose of stable input and output.

[0099] S404: When the information processed by the regulation decision-making module is that the power grid load is less than the preset value, or the fast charging power is less than the high-power critical value, or the energy storage capacity is less than the minimum energy release capacity, a stop work instruction is sent to the water release and energy release module.

[0100] Specifically, the fourth control valve 17, the sixth control valve 18, and the ninth control valve 21 can be closed, and the third coupling 24 and the fourth coupling 25 can be disconnected.

[0101] It should also be noted that the term "including", "comprising" or any other variant thereof in this specification is intended to cover non-exclusive inclusion, that is, in addition to the elements listed in this specification, other elements not expressly listed may also be included.

[0102] Each embodiment in this specification is described in a progressive manner. The same or similar parts between each embodiment can be referred to each other, and the key points of each embodiment are the differences from other embodiments.

[0103] The above is only the embodiment of this specification and is not used to limit this specification. For those skilled in the art, various changes and modifications can be made to this specification. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this specification shall be included within the scope of the claims of this specification.

Claims

1. A power grid power regulation system, characterized in that: include: A pumped energy storage device, including a nitrogen pressure regulating module, a pumped energy storage module, and a water release module; The nitrogen pressure regulating module comprises a nitrogen tank (1), a compressor (2), a water-nitrogen coexistence tank (4) and a motor (9), wherein the nitrogen tank (1), the compressor (2) and the water-nitrogen coexistence tank (4) are connected in sequence, and the motor (9) is connected to the compressor (2) and is used to drive the compressor (2) to pressurize the nitrogen in the nitrogen tank (1) and send it into the water-nitrogen coexistence tank (4); The pumped energy storage module comprises a water-nitrogen coexistence tank (4), a pump (8), a water tank (12) and a motor (9), wherein the water tank (12), the pump (8) and the water-nitrogen coexistence tank (4) are connected in sequence, and the motor (9) is connected to the pump (8) and is used to drive the pump (8) to pressurize and transport the liquid in the water tank (12) to the water-nitrogen coexistence tank (4); The water-energy release module comprises a water-nitrogen coexistence tank (4), a first water turbine (5), a first generator (10) and a water tank (12), wherein the water-nitrogen coexistence tank (4), the first water turbine (5) and the water tank (12) are connected in sequence, and the first generator (10) is connected to the first water turbine (5); The data acquisition module is electrically connected to the pumped energy storage device, the power grid, and the charging pile respectively; The control decision module is electrically connected to the data acquisition module and the pumped energy storage device respectively; When the data acquisition module simultaneously obtains status information that the energy storage capacity of the pumped energy storage device is less than the maximum energy storage capacity, the power grid is in a non-peak-shaving state, and the power grid is in a low-load state, the control decision module sends a pumped energy storage instruction to the pumped energy storage module, and the pumped energy storage module pressurizes the liquid in the water tank (12) and sends it into the water-nitrogen coexistence tank (4) through a pump (8); the charging pile is powered by the power grid; When the data acquisition module obtains information that the power grid is in a peak load state or a high load state, and the energy storage capacity of the pumped energy storage device is greater than the minimum energy release capacity, the power grid supplies power to the charging pile; and the control decision module issues a water energy release instruction to the water energy release module, and the water energy release module controls the water-nitrogen coexistence tank (4) to release liquid into the first turbine (5) to drive the first generator (10) to generate electricity, and the first generator (10) supplies power to the charging pile; The pumped energy storage device further comprises: a pressure stabilizing tank (3), a first control valve (13), a second control valve (14), a third control valve (15), a fourth control valve (17), and a fifth control valve (20); The water-nitrogen coexistence tank (4) comprises a first inlet (201), a second inlet (202), and a first outlet (203); The outlet of the nitrogen tank (1) is connected to the inlet of the compressor (2) through the second control valve (14), the outlet of the compressor (2) is connected to the inlet of the pressure stabilizing tank (3), the first outlet of the pressure stabilizing tank (3) is connected to the first inlet (201) of the water-nitrogen coexistence tank (4) through the third control valve (15), and the second outlet of the pressure stabilizing tank (3) is connected to the inlet of the nitrogen tank (1) through the first control valve (13); The first outlet (203) of the water-nitrogen coexistence tank (4) is connected to the inlet of the first water turbine (5) through the fourth control valve (17), and the outlet of the first water turbine (5) is connected to the first inlet of the water tank (12); The first outlet of the water tank (12) is connected to the inlet of the pump (8) through the fifth control valve (20), and the outlet of the pump (8) is connected to the second inlet (202) of the water-nitrogen coexistence tank (4); The motor (9) is connected to the compressor (2) via a first coupling (22), and the motor (9) is connected to the pump (8) via a second coupling (23); The pumped energy storage device further comprises: a sixth control valve (18), a seventh control valve (19), an eighth control valve (16), a second water turbine (6), a third coupling (24), and a fourth coupling (25); The first outlet (203) of the water-nitrogen coexistence tank (4) is divided into two paths, the first path is connected to the inlet of the first water turbine (5) through the fourth control valve (17), and the second path is connected to the outlet of the first water turbine (5) through the eighth control valve (16); After merging, the water flows are further divided into two branches, the first branch being connected to the inlet of the second water turbine (6) through a sixth control valve (18), and the second branch being connected to the outlet of the second water turbine (6) through a seventh control valve (19) and then entering the first inlet of the water tank (12); The first generator (10) is connected to the first turbine (5) via a third coupling (24), and the first generator (10) is connected to the second turbine (6) via a fourth coupling (25); The first water turbine (5) and the second water turbine (6) are arranged in series or in parallel; The pumped energy storage device further comprises: a ninth control valve (21), a third water turbine (7), and a second generator (11); the water-nitrogen coexistence tank (4) further comprises a second outlet (204); The second outlet (204) of the water-nitrogen coexistence tank (4) is connected to the inlet of the third water turbine (7) through a ninth control valve (21), and the outlet of the third water turbine (7) is connected to the second inlet of the water tank (12); The water-nitrogen coexistence tank (4) comprises a hydraulic pump (205), a hydraulic rod (206), a partition (207), and a tank body (208); the control decision module is connected to the hydraulic pump (205); The control decision module drives the hydraulic rod (206) through the hydraulic pump (205), so that the hydraulic rod (206) generates pressure or tension on the partition (207), thereby adjusting the pressure of water in the water-nitrogen coexistence tank (4); When the power grid is in a high-load state and the energy storage capacity of the pumped energy storage device is greater than the minimum energy release capacity, the charging pile is disconnected from the power grid. According to the energy release instruction issued by the control decision module, the water release module of the pumped energy storage device executes the first load mode: the fourth control valve (17) and the seventh control valve (19) are opened, the third coupling (24) is closed, and the other valves and couplings remain closed. The liquid in the water-nitrogen coexistence tank (4) flows out and enters the first turbine (5), driving the first generator (10) to rotate and generate electricity, and the generated electric energy is input into the charging pile to meet the needs of fast charging power. When the power demand of the charging pile increases to a value greater than the first threshold, the control decision module issues a load increase instruction, the hydraulic pump (205) starts to increase pressure, drives the hydraulic rod (206) to transmit pressure to the partition (207), the water pressure in the tank increases, and the device power increases. When the second load critical value is reached, the water release module executes the second load mode, the hydraulic pump (205) stops working, the pressure in the water-nitrogen coexistence tank (4) gradually recovers, the seventh control valve (19) is closed, the sixth control valve (18) is opened, the fourth coupling (25) is closed, the second turbine (6) is put into operation, the first turbine (5) and the second turbine (6) jointly drive the first generator (10) to generate electricity, and the electric energy is input into the charging pile to meet the needs of the increased charging load. When the power demand of the charging pile increases to a value greater than the second threshold, the control decision module issues a parallel load increase instruction, the hydraulic pump (205) starts to increase pressure, drives the hydraulic rod (206) to transmit the pressure to the partition (207), the water pressure in the tank increases, and the power of the device increases. When the third load critical value is reached, the water release module executes the third load mode, the hydraulic pump (205) stops working, the pressure in the water-nitrogen coexistence tank (4) gradually recovers, the ninth control valve (21) is opened, the third turbine (7) is put into operation, and the high-pressure water in the water-nitrogen coexistence tank (4) enters the third turbine (7) to perform work, driving the second generator (11) to generate electricity. The two generators generate electricity simultaneously and input electrical energy into the charging pile.

2. The power grid power regulation system according to claim 1, characterized in that: The partition (207) is a variable resistance partition, and the output power of the pumped energy storage device is adjusted by adjusting the friction between the partition (207) and the tank body (208); When the friction force increases, the movement speed of the partition (207) decreases, the water pressure at the outlet of the water-nitrogen coexistence tank (4) decreases, and the output power of the pumped energy storage device decreases; When the friction force decreases, the movement speed of the partition (207) increases, the water pressure at the outlet of the water-nitrogen coexistence tank (4) increases, and the output power of the pumped water energy storage device increases.

3. The power grid power regulation system according to claim 1, characterized in that: The nitrogen tank (1) is also used to supplement the water-nitrogen coexistence tank (4) with nitrogen through a compressor as required; or, the first control valve (13) is also used to open as required to allow the nitrogen in the pressure regulating tank (3) to flow back to the nitrogen tank (1), so as to reduce the nitrogen pressure in the water-nitrogen coexistence tank (4) and regulate the energy storage capacity of the pumped energy storage device.

4. A power grid power regulation method based on a power grid power regulation system, characterized in that: include: Initialize the status of all valves in the power regulation system of the power grid, and according to the preset maximum energy storage capacity, supply nitrogen to the water-nitrogen coexistence tank through the nitrogen pressure regulating module until the preset pressure corresponding to the maximum energy storage capacity is reached; The data acquisition module collects the load status of the power grid and the energy storage capacity of the pumped energy storage device under the operating power of the charging pile in real time; When the power grid is in a low-load and non-peak-shaving state, the charging pile is powered by the power grid; at the same time, if the pumped energy storage device has not reached the maximum energy storage capacity, the pumped energy storage module is issued a pumped energy storage instruction through the control decision module, so that the pumped energy storage device executes the pumped energy storage process to obtain energy from the power grid and store it; When the power grid is in a high load or peak load state, and the pumped energy storage device is greater than the minimum energy release capacity, the charging pile is disconnected from the power grid, and a water energy release instruction is issued to the pumped energy storage module through the control decision module, so that the pumped energy storage device executes the water release process to power the charging pile; When the power grid is in a high-load state and the energy storage capacity of the pumped energy storage device is greater than the minimum energy release capacity, the charging pile is disconnected from the power grid. According to the energy release instruction issued by the control decision module, the water release module of the pumped energy storage device executes the first load mode, and the liquid in the water-nitrogen coexistence tank flows out and enters the first turbine, driving the first generator to rotate and generate electricity, and the generated electricity is input into the charging pile to meet the needs of fast charging power. When the power demand of the charging pile increases to a value greater than the first threshold, the control decision module issues a load increase command, the hydraulic pump starts to increase pressure, drives the hydraulic rod to transfer pressure to the partition, the water pressure in the tank increases, and the device power increases. When the second-level load critical value is reached, the water release module executes the second-level load mode, the hydraulic pump stops working, and the pressure in the water-nitrogen coexistence tank gradually recovers. The second turbine is put into operation, and the first turbine and the second turbine jointly drive the first generator to generate electricity, and input electrical energy into the charging pile to meet the needs of increased charging load. When the power demand of the charging pile increases to a value greater than the second threshold, the control decision module issues a parallel load increase command, the hydraulic pump starts to increase pressure, drives the hydraulic rod to transfer pressure to the partition, the water pressure in the tank increases, and the power of the device increases. When the third-level load critical value is reached, the water release module executes the third-level load mode, the hydraulic pump stops working, the pressure in the water-nitrogen coexistence tank gradually recovers, the third turbine is put into operation, and the high-pressure water in the water-nitrogen coexistence tank enters the third turbine to perform work, driving the second generator to generate electricity. The two generators generate electricity simultaneously and input electrical energy into the charging pile.

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