Car-type pumping system of pumped storage power station

Abstract

The present invention discloses a car-type pumping system of a pumped-storage power station, which includes a first reservoir and a second reservoir that are independent of each other, adjacent to each other and connected by a water pipe; the water level of the first reservoir is higher than that of the second reservoir to ensure sufficient power generation height difference; a pumping-generating integrated machine, which pumps water from the second reservoir to the first reservoir during the off-peak period of electricity consumption to clear the storage capacity of the second reservoir; during the peak period of electricity consumption, the water flow from the first reservoir into the second reservoir is used to generate electricity; a telescopic water pipe connected to the water pipe is connected above the pumping-generating integrated machine; the pumping-generating integrated machine is located in a car, and the car can be raised and lowered in the second reservoir to change its height; the telescopic water pipe can change its working length as the car is raised and lowered; the car is also provided with a sensor, which monitors the relative position of the car and the water surface of the second reservoir.

Description

Technical Field

[0001] The present invention belongs to the field of physical energy storage in electric energy storage systems, and in particular relates to a car-type pumping system of a pumped energy storage power station. Background Art

[0002] As the construction of new power systems continues to advance, they are characterized by a high proportion of renewable energy and power electronic equipment. However, renewable energy generation technologies such as wind and solar power suffer from instability, randomness, and intermittency, making them prone to supply and demand mismatches. Specifically, wind and photovoltaic power stations generate the most power in the early morning and midday, respectively, while peak electricity consumption occurs at 10 a.m. and 8 p.m. The distribution of these power stations' peak generation times is significantly misaligned with peak load times. This mismatch between peak generation and peak demand results in excess electricity being wasted during peak generation periods. However, peak demand periods are not peak generation periods, leading to grid overload and insufficient supply. Furthermore, seasonal and weather factors exacerbate the instability of energy generation. As the proportion of volatile and intermittent renewable energy in the power supply structure continues to grow, the supply side will also show random fluctuations. Grid frequency control is becoming increasingly important, and the demand for peak and frequency regulation is becoming increasingly urgent. An effective way to solve this problem is to use an energy storage system to store a large amount of abundant low-priced electricity during peak power generation periods, and use the energy storage system to smooth the output of power system power generation and shave peaks and fill valleys, thereby balancing the load on the power grid.

[0003] Electric energy storage includes various methods, including mechanical, electrochemical, electromagnetic, thermal, and chemical. The most common electrochemical method uses a large number of batteries for charging and discharging. Mechanical methods include pumped hydro, gravity, and compressed air. Pumped hydro is also a form of gravity storage, leveraging the abundant, low-cost electricity available from the grid during peak power generation periods to pump water to a higher reservoir (such as a mountaintop reservoir). During peak power demand, the water is then diverted to a generator set for hydroelectric generation, utilizing the water's potential energy. A common method of mountaintop reservoir storage involves pumping water from a low-lying area to a higher-lying reservoir, such as a mountaintop. During peak power demand, gates are opened to release the water, which impacts the impellers of a hydroelectric generator, generating electricity. Another method involves directly utilizing natural lakes, caves, or mines, diverting water from rivers and lakes above these low-lying areas directly to the lower mines for power generation. This approach, by leveraging naturally occurring favorable terrain or utilizing it for secondary use, can significantly reduce the construction cost of energy storage power stations and further increase profitability. This approach has been widely exploited in recent years, as surveys have revealed the presence of such favorable terrain in many areas of my country, such as Fujian and Zhejiang. However, unlike traditional artificial reservoirs built at elevated locations for energy storage, these reservoirs have the generator impeller located below. When the water that propels the impeller enters lower-lying rivers or natural lakes, the water level below the impeller is largely unaffected by the reservoir's capacity. However, in low-lying locations like mines, such as those used to build energy storage power stations, as hydroelectric power generation continues, the water level within the pit will gradually rise, due to the limited storage capacity of the mine pit. At this point, the generator impeller, located at the lowest point to maximize the use of hydraulic potential energy, gradually sinks into the water, creating resistance and reducing efficiency. Furthermore, excessively long diversion pipes reduce the pump's head capacity during pumping, increasing energy consumption. Energy storage power stations themselves generate profits by taking advantage of the price difference between peak and low electricity consumption periods. Therefore, they are very sensitive to their own operating efficiency. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a car-type pumping system for a pumped energy storage power station, which can change the position of the impeller or unit at any time according to the change of water level, thereby improving the operation efficiency.

[0005] To solve the above problems, the present invention provides a car-type pumping system for a pumped-storage power station. The pumped-storage power station includes a first reservoir and a second reservoir that are independent of each other but adjacent to each other. The water level of the first reservoir is higher than that of the second reservoir, and the bottom of the second reservoir is lower than that of the first reservoir to ensure sufficient head height for power generation. The first reservoir and the second reservoir are connected by a water pipe.

[0006] A pumping generator, which operates as a water pump during off-peak periods, pumping water from the second reservoir to the first reservoir to free up the second reservoir's capacity. A telescopic water conduit is connected to the top of the pumping generator, allowing for variable length.

[0007] The impeller of the pumped hydro generator is located below the end of the water conduit of the second reservoir. During peak electricity consumption, the pumped hydro generator operates as a generator, generating hydroelectric power by utilizing the water level difference between the first and second reservoirs. The pumped hydro generator is located in a car, and the car structure moves up and down along a vertical guide rail vertically disposed in the second reservoir.

[0008] The pumping and power generation unit is located in the car, and a water pipe with a retractable length is installed above the car. The outlet of the water pipe is located at the water surface of the first reservoir. The impeller of the pumping and power generation unit is located at the end of the water pipe at the second reservoir.

[0009] The peak period of electricity consumption and the valley period of electricity consumption refer to the load status of the external social public power grid; the peak period of electricity consumption is the power generation stage of the pumped storage power station, and the valley period of electricity consumption is the energy storage stage of the pumped storage power station.

[0010] Furthermore, the first reservoir is a natural river, stream, lake or other natural water resource whose storage capacity can be regarded as unlimited, and the impact of its water level fluctuation on the pumped storage power station can be ignored.

[0011] Furthermore, the second reservoir is lower than the first reservoir and has a sufficient height difference with the first reservoir to carry out hydroelectric power generation; the second reservoir is a mine, pond, cave or other water storage landform with a certain storage capacity located in a low-lying area; the second reservoir serves as a water storage facility of a pumped storage power station.

[0012] Furthermore, the pumped energy storage power station also includes a control system, which is connected to the pumped power generator and the car to monitor their working status and control their operation.

[0013] Furthermore, the water pipe between the first reservoir and the second reservoir is also provided with a first electric gate valve, the switch of which is controlled by the control system to adjust or cut off the water flow between the first reservoir and the second reservoir.

[0014] Furthermore, the impeller of the integrated pumped generator is connected to the end of the water pipe and is located above the water surface of the second reservoir; the water of the first reservoir is led to the impeller of the generator through the water pipe and the water pipe, driving the impeller to rotate to achieve power generation; when the pumped energy storage power station is in the power generation state, the water level of the second reservoir gradually rises, and the control system controls the car to move upward, raising the car where the integrated pumped generator and its impeller are located, so as to ensure that the impeller is always above the water surface of the second reservoir, reducing the operating resistance of the impeller and achieving the highest water flow utilization rate.

[0015] Furthermore, a sensing device is installed in the car, which can sense the water surface and measure the relative distance between the impeller and the water surface of the second reservoir. When the water level of the second reservoir changes, the sensing device links the control system to control the lifting and lowering of the car, so that the impeller always remains in the position with the most efficient water flow utilization, thereby improving the power generation efficiency.

[0016] Furthermore, the integrated pumping and power generation machine pumps water from the second reservoir to the first reservoir. During the energy storage stage of pumping water to the first reservoir, the height of the car is maintained so that the impeller of the water pump is below the water surface of the second reservoir; when continuous pumping causes the water level of the second reservoir to drop, the car also gradually descends along the guide rail in the shaft to keep the relative position of the impeller and the water surface of the second reservoir unchanged, so as to reduce the operating load of the water pump and reduce energy consumption.

[0017] Furthermore, the car is raised and lowered along the guide rail by a hoisting winch system arranged at the top that retracts and extends the steel cable connecting the car, so that the car moves up and down along the guide rail in the second reservoir, adjusts its relative position with the water surface of the second reservoir, and links the retractable water pipe to retract and extend together.

[0018] Furthermore, the car is raised and lowered along the guide rail by the relative movement between the gear driven by the motor fixed on the car and the rack on the guide rail; the rack extends along the guide rail and is fixed on the guide rail, and the gear driven by the motor is engaged with the teeth on the rack. When the motor drives the gear to rotate, the gear and the fixed rack are phase-shifted, thereby synchronously driving the car to be raised and lowered.

[0019] Furthermore, the telescopic water pipe with variable length is a multi-layer sleeve structure or a bellows structure.

[0020] Furthermore, the car also includes a brake system, which can lock the connection between the car and the guide rail to prevent sliding when the car does not need to be raised or lowered.

[0021] Furthermore, the integrated pumping and power generation machine can be replaced by independent water pumps and generators, which are respectively connected to their own retractable water pipes.

[0022] Furthermore, the guide rail is arranged inside the water pipe and integrated with the water pipe, saving external installation space.

[0023] Furthermore, the guide rail is arranged outside the water pipe to form a single guide rail or a guide rail of a portal structure, thereby improving load capacity and stability.

[0024] The car-type pumping system of the pumped-storage power station described in the present invention, by arranging the pumping and generator integrated machine of the pumped-storage power station in a liftable car structure, enables the car to move up and down with changes in water level, always keeping the water pump or generator in an optimized operating position, further improving the operating efficiency, maximizing the energy storage efficiency of the entire pumped-storage power station, and achieving higher economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of a first embodiment of a car-type pumping system of a pumped energy storage power station of the present invention, which is a sleeve-type guide rail-free structure.

[0026] Figure 2 This is a schematic diagram of a second embodiment of the car-type pumping system of the pumped energy storage power station of the present invention, including a guide rail system.

[0027] Figure 3 This is an enlarged view of the structure inside the car of the car-type pumping system of the present invention, including the end of the water pipe, the impeller, the pumping and power generation integrated machine and the related supporting platform.

[0028] 1 is the second reservoir (abandoned mine, cave, etc.), 2 is the pit body, 3 is the telescopic water pipe (sleeve), 4 is the first reservoir (river, lake, etc.), 5 is the water pipe or diversion channel, 6 is the energy storage power station building, 7 is the winch, 8 is the (electric) valve, 9 is the car drive wire rope, 10 is the sealing ring, 11 is the transmission bevel gear, 12 is the coupling, 13 is the pumping power generation integrated machine, 14 is the sensing device (water surface sensor), 15 is the car, 16 is the impeller, and 17 is the guide rail. Implementation Method

[0029] The following is a specific embodiment of the present invention in conjunction with the accompanying drawings, which clearly and completely describes the technical solutions in the present invention, but the present invention is not limited to the following embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. According to the following description and claims, the advantages and features of the present invention will be clearer. It should be noted that the drawings are all in a very simplified form and use non-precise ratios, which are only used to conveniently and clearly assist in explaining the embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] The present invention can be implemented in different forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, providing these embodiments will make the disclosure thorough and complete and fully convey the scope of the present invention to those skilled in the art. In the accompanying drawings, for clarity, the sizes and relative sizes of layers and regions may be exaggerated, and the same reference numerals represent the same elements throughout. In the description of this application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0031] The present invention discloses a car-type pumping system for a pumped energy storage power station. The pumped energy storage power station is an energy storage system that is constructed by basically utilizing the natural environment or abandoned artificial environment. Figure 1 As shown, it includes a first reservoir 4 and a second reservoir 1 that are independent of each other and adjacent to each other; the water level of the first reservoir 4 is higher than that of the second reservoir 1, and the bottom of the second reservoir 1 is much lower than the water level of the first reservoir to ensure sufficient power generation height difference; the first reservoir 4 can be a natural river, river, lake or other natural water resources, and its water resource storage capacity can be regarded as an unlimited water resource for this energy storage power station system, and the impact of its water level difference fluctuation on the pumped storage power station described in the present invention can be ignored.

[0032] The second reservoir 1 is located lower than the first reservoir 4 and has a sufficient water level difference with the first reservoir to generate hydroelectric power. The second reservoir 1 is located in a low-lying abandoned mine, pond, natural deep pit, cave, or other water storage landform with a certain storage capacity; the second reservoir 1 serves as the water storage facility of the pumped storage power station.

[0033] The first reservoir and the second reservoir are connected by a water pipeline or a diversion channel, and the connection form is not limited. The water pipeline also has a valve or an electric valve, which is controlled by the control system and can adjust or cut off the water flow between the first reservoir and the second reservoir when necessary.

[0034] The car includes a pumping power generation unit and corresponding supporting structures. Figure 1 Combined with attachment Figure 3 As shown, during off-peak periods (i.e., when electricity prices are relatively low), the pumped hydro generator pumps water from the second reservoir into the first reservoir to free up the second reservoir's capacity, representing the energy storage phase. A telescopic water conduit (sleeve-shaped) 3 is connected to the top of the pumped hydro generator. During peak periods (i.e., when electricity prices are relatively high), the pumped hydro generator operates as a generator, utilizing the water level difference between the first and second reservoirs to generate hydroelectric power during peak periods.

[0035] Of course, the aforementioned integrated pumping and power generation unit 13 is an integrated design that is currently widely used and has a more compact structure. In some applications, a traditional design of an independent water pump + generator can also be adopted to independently perform the functions of pumping and power generation. When a design method in which the water pump and generator are each independent is adopted, it is necessary to connect the water pump and generator to their own equally retractable water conduits. Those skilled in the art should be able to understand and implement their design and working methods. The present invention will not be elaborated in detail here, and the embodiments of the present invention will still be described using an integrated design.

[0036] The pumping power generation integrated machine is in the car, and a water pipe 3 with a retractable and variable length is installed above it. One end of the water pipe is connected to the water supply pipe or the diversion channel, and the outlet of the water pipe is located at the impeller position on the water surface of the first reservoir; the impeller 16 of the pumping power generation integrated machine is located at the end of the water pipe at the water surface position of the second reservoir.

[0037] The retractable water conduit can be designed as a sleeve or a bellows. In the design without guide rails, a sleeve-type connection structure can be used, which can ensure the retractability and at the same time the water conduit of the sleeve structure can have sufficient support strength to support the weight of the entire car including the impact of water flow. Figure 1 shown.

[0038] In addition, the present invention also provides an additional embodiment 2, such as Figure 2 The figure shows a lifting system that includes a guide rail structure. The entire car structure moves up and down along the guide rails. The guide rails help support the entire car and resist water impact. Therefore, the water conduit can adopt a sleeve structure or a bellows structure, which provides greater flexibility. The lifting and lowering of the car structure is achieved by the hoisting winch system 7 and wire rope 9.

[0039] The guide rail can be set as a single guide rail structure, integrated into the sleeve-type water pipe, or a double guide rail can be used to form a gantry system located outside the water pipe, which has the highest structural strength. The appropriate solution can be freely selected according to actual conditions. Figure 2 The single guide rail structure shown in FIG is located outside the water pipe 3 , and the entire car platform rises and falls along the guide rail.

[0040] In some applications, the elevator car can be raised and lowered by fixing an electric motor in the car and installing a rack on the entire guide rail. The motor drives a gear that meshes with the rack. When the gear rotates, it moves up and down along the rack, thereby driving the entire elevator car platform up and down. This can replace the aforementioned hoisting system and omit the wire rope and pulley system.

[0041] The car also includes a sensor capable of sensing the position of the water surface or monitoring the relative position of the car and the water surface of the second reservoir, and transmitting the corresponding position information to a control system. The control system controls the raising and lowering of the car platform based on the water level information sensed by the sensor to ensure that the relative position of the impeller and the water surface meets the design expectations.

[0042] The control system of the pumped energy storage power station is connected to the pumped power generation integrated machine and the car to monitor their working status and control their operation.

[0043] The peak and valley periods of electricity consumption refer to the load status of the external public power grid; the peak period of electricity consumption is the power generation phase of the pumped-storage power station, and the valley period of electricity consumption is the energy storage phase of the pumped-storage power station. The peak period of electricity consumption has higher city electricity prices, while the valley period of electricity consumption has cheaper city electricity prices. The pumped-storage power generation unit uses cheaper city electricity for pumping and energy storage during valley periods, and uses hydropower for power generation during peak periods. The generated electricity is sold to the public power grid, and profits are realized by taking advantage of the higher city electricity prices at this time.

[0044] During the power generation phase:

[0045] At this time, the water level of the second reservoir is at a low water level that basically empties the storage capacity. The pumped-water generator is working in a power generation state. The impeller is connected to the end of the water guide pipe and is located above the water surface of the second reservoir. The water from the first reservoir is led to the impeller of the pumped-water generator through the water pipe and the water guide pipe, driving the impeller to rotate to achieve power generation. When the pumped-water energy storage power station is in a power generation state, the water surface of the second reservoir gradually rises. A water level sensor is installed in the car. The water level sensor can sense the position of the water level, measure the relative distance between the impeller and the water surface of the second reservoir, and send water level information to the control system.

[0046] The control system receives a water level control signal and controls the car to move upward, raising the pumped-water generator set and its impeller to ensure that the impeller is always above the water surface of the second reservoir, thereby reducing the operating resistance of the impeller and achieving the highest water flow utilization rate.

[0047] During the energy storage phase:

[0048] The pumping generator is now operating in a pumping state, and the second reservoir is at a high water level that is basically full of water. The water from the second reservoir is pumped to the first reservoir. During the energy storage stage of pumping water to the first reservoir, the height of the car is maintained so that the impeller of the pumping generator is located below the water surface of the second reservoir, rather than being completely submerged in the deeper bottom of the second reservoir, so as to achieve the shortest possible working length of the water pipe to reduce operating resistance; when continuous pumping causes the water level of the second reservoir to drop, the car also gradually descends along the guide rail or directly by the sleeve structure to keep the relative position of the impeller and the water surface of the second reservoir unchanged. This reduces the operating load of the pumping generator and reduces energy consumption.

[0049] The car is raised and lowered along the guide rails by a hoisting winch system installed at the top of the shaft, which retracts and extends the steel cable connecting the car, causing the car to move up and down in the second reservoir and adjust its relative position to the water surface of the second reservoir. Alternatively, the car can be raised and lowered by the relative movement of a gear driven by an electric motor fixed to the car and a rack mounted on the guide rails in the shaft. The rack extends along the guide rails and is fixed to the guide rails, and the gear driven by the motor meshes with the teeth on the rack. When the motor drives the gear to rotate, the gear and the fixed rack are phase-shifted, synchronously driving the car up and down.

[0050] When the car moves up and down due to changes in water level, the water pipe needs to be synchronously extended and retracted to change its length to match the position of the car. The water pipe can adopt a sleeve structure or a bellows structure, which can be achieved in conjunction with a corresponding guiding device.

[0051] The car also includes a brake system, which can lock the connection between the car and the guide rail to prevent sliding when the car does not need to be raised or lowered.

[0052] The car-type pumping system of the pumped-storage power station described in the present invention, by arranging the pumped-water generator of the pumped-water generator in a liftable car structure, enables the car to move up and down with changes in the water level, always keeping the impeller of the pumped-water generator in an optimized operating position, further improving the operating efficiency, maximizing the energy storage efficiency of the entire pumped-storage power station, and achieving higher economic benefits.

[0053] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A car-type pumping system for a pumped energy storage power station, characterized by: The pumped storage power station comprises a first reservoir and a second reservoir which are independent of each other but adjacent to each other; the water level of the first reservoir is higher than that of the second reservoir, and the bottom of the second reservoir is lower than that of the first reservoir to ensure sufficient height difference for power generation; the first reservoir and the second reservoir are connected by a water pipe; A pumping generator, which operates as a water pump during off-peak periods, pumping water from the second reservoir to the first reservoir to free up the second reservoir's capacity. A telescopic water pipe is connected to the top of the pumping generator, allowing the pipe length to be adjusted by telescoping. The impeller of the pumped-water generator is located below the end of the water conduit of the second reservoir. During peak electricity consumption, the pumped-water generator operates in a generator state, utilizing the water level difference between the first reservoir and the second reservoir to generate hydroelectric power. The pumped-water generator is located in a car that can move up and down perpendicular to the water surface of the second reservoir. The car can move up and down with changes in the water level of the second reservoir. During the power generation phase, the height of the car ensures that the impeller of the pumped-water generator is above the water surface of the second reservoir. During the energy storage phase, the height of the car ensures that the impeller of the pumped-water generator is below the water surface of the second reservoir. The peak period of electricity consumption and the valley period of electricity consumption refer to the load status of the external social public power grid; the peak period of electricity consumption is the power generation stage of the pumped storage power station, and the valley period of electricity consumption is the energy storage stage of the pumped storage power station.

2. The car-type pumping system of the pumped energy storage power station according to claim 1, characterized in that: The first reservoir is a natural river, stream, lake or other natural water resource whose storage capacity can be regarded as unlimited, and the impact of its water level fluctuation on the pumped storage power station can be ignored.

3. The car-type pumping system of the pumped energy storage power station according to claim 2, characterized in that: The second reservoir is lower than the first reservoir and has a sufficient height difference with the first reservoir to carry out hydroelectric power generation; the second reservoir is a mine, pond, cave or other water storage landform with a certain storage capacity located in a low-lying area; the second reservoir serves as a water storage facility of a pumped storage power station.

4. The car-type pumping system of the pumped energy storage power station according to claim 1, characterized in that: The pumped energy storage power station further includes a control system, which is connected to the pumped power generator and the car to monitor their working conditions and control their operation.

5. The car-type pumping system of the pumped storage power station according to claim 4, characterized in that: The water pipe between the first reservoir and the second reservoir is further provided with a first electric gate valve, the switch of which is controlled by the control system to adjust or cut off the water flow between the first reservoir and the second reservoir.

6. The car-type pumping system of the pumped storage power station according to claim 1, characterized in that: The water from the first reservoir is led to the impeller of the pumped-water generator through a water pipe and a water guide pipe, driving the impeller to rotate to generate electricity; when the pumped-water energy storage power station is in a power generation state, the water level of the second reservoir gradually rises, and the control system controls the car to move upward, raising the car where the pumped-water generator and its impeller are located, so as to ensure that the impeller is always above the water surface of the second reservoir, reduce the operating resistance of the impeller, and achieve the highest water flow utilization rate.

7. The car-type pumping system of the pumped storage power station according to claim 6, characterized in that: A sensing device is installed in the car, which can sense the water surface and measure the relative distance between the impeller and the water surface of the second reservoir. When the water level of the second reservoir changes, the sensing device links the control system to control the lifting and lowering of the car, so that the impeller always remains in the position with the most efficient water flow utilization, thereby improving the power generation efficiency.

8. The car-type pumping system of the pumped energy storage power station according to claim 5, characterized in that: During the energy storage stage of pumping water to the first reservoir, the pumping power generation integrated machine pumps water from the second reservoir to the first reservoir, and the height of the car is maintained so that the impeller of the water pump is below the water surface of the second reservoir; when continuous pumping causes the water level of the second reservoir to drop, the car also gradually descends along the guide rail in the shaft to keep the relative position of the impeller and the water surface of the second reservoir unchanged, so as to reduce the operating load of the water pump and reduce energy consumption.

9. The car-type pumping system of the pumped energy storage power station according to claim 1, characterized in that: The car can move up and down perpendicular to the water surface of the second reservoir, and is raised and lowered along a vertical guide rail. The steel cable connecting the car is retracted and pulled by a lifting winch system arranged at the top, so that the car can move up and down along the guide rail in the second reservoir, adjust its relative position with the water surface of the second reservoir, and link the retractable water pipe to retract and retract together.

10. The car-type pumping system of the pumped storage power station according to claim 1, characterized in that: The car can move up and down perpendicular to the water surface of the second reservoir, and is raised and lowered along a vertical guide rail. The raising and lowering of the car is achieved by relative movement between a gear driven by an electric motor fixed on the car and a rack on the guide rail; the rack extends along the guide rail and is fixed on the guide rail, and the gear driven by the motor meshes with the teeth on the rack. When the motor drives the gear to rotate, the gear and the fixed rack are phase-displaced, thereby synchronously driving the raising and lowering of the car.

11. The car-type pumping system of the pumped storage power station according to claim 1, characterized in that: The telescopic water pipe with variable length is a multi-layer sleeve structure or a bellows structure.

12. The car-type pumping system of the pumped storage power station according to claim 1, characterized in that: The car also includes a brake system, which can lock the connection between the car and the guide rail to prevent sliding when the car does not need to be raised or lowered.

13. The car-type pumping system of the pumped storage power station according to claim 1, characterized in that: The integrated pumping and power generation machine can be replaced by independent water pumps and generators, which are respectively connected to their own retractable water pipes.

14. The car-type pumping system of a pumped storage power station according to claim 9 or 10, characterized in that: The guide rail is arranged inside the water pipe and integrated with the water pipe, saving external installation space.

15. The car-type pumping system of the pumped storage power station according to claim 9 or 10, characterized in that: The guide rail is arranged outside the water pipe to form a single guide rail or a guide rail of a portal structure, thereby improving the load capacity and stability.

Images