Gravity energy storage power recovery system based on hydraulic compressed air energy storage

Abstract

The utility model discloses a gravity energy storage power recovery system based on hydraulic compressed air energy storage. The gravity energy storage power recovery system comprises a gravity energy storage system and a kinetic energy recovery system. A generator motor of the gravity energy storage system is sequentially connected with an energy storage driving clutch, an energy storage driving clutch, a brake device and a winding drum through a gearbox by utilizing a rotating shaft; the kinetic energy recovery system clutch is connected with one side of the winding drum, the other side of the winding drum is connected with the variable pump / turbine through the gearbox, an inlet and an outlet of the variable pump / turbine are connected with the oil tank and the energy accumulator respectively, and an inlet and an outlet of the overflow valve are connected with the energy accumulator and the oil tank respectively. In the stopping stage when the weight block of the gravity energy storage system is lifted and energy release is finished, the kinetic energy recovery system absorbs waste kinetic energy transmitted by the gravity energy storage system and converts the waste kinetic energy into liquid compressed air energy to be stored; and in the starting stage of starting lifting of the weight block and starting of energy release, the liquid compressed air energy is released and used for accelerating the weight block to the speed close to the rated running speed of the weight block, and recycling of kinetic energy is achieved.

Description

Technical Field

[0001] The utility model belongs to the technical field of gravity energy storage, and in particular relates to a gravity energy storage power recovery system based on hydraulic compressed air energy storage. Background Art

[0002] During the energy storage process, the weight block of the gravity energy storage system is driven by an electric motor to be lifted from a low position to a high position. During the energy release process, the weight block releases its gravitational potential energy from a high position and falls back to a low position, driving the generator to generate electricity and supply electricity to the power grid.

[0003] During the startup phase when the heavy object begins to be lifted and energy is released, it is necessary to consider how to accelerate the heavy object to the rated operating speed so as to drive the motor to generate electricity and connect to the grid normally. Currently, a frequency converter is usually used to configure an asynchronous generator or other acceleration means are used to accelerate the running speed of the heavy object to the rated operating speed of the synchronous generator.

[0004] During the shutdown stage when the heavy object is lifted and the energy is released, it is usually necessary to use a brake system to slow down and brake, and adjust the running speed of the heavy object from the rated value to a static state. Due to the huge mass of the heavy object, if the brake is used solely for deceleration and braking, it will cause a large energy loss. Utility Model Content

[0005] In response to the problems existing in the prior art, the utility model provides a gravity energy storage power recovery system based on hydraulic compressed air energy storage, which can recover the operating kinetic energy of heavy objects at the end of lifting and the end of energy release and the shutdown stage, and convert it into liquid potential difference energy release and compressed air compression energy for storage; in the startup stage when the heavy object starts to be lifted and the energy release begins, the stored energy is released to accelerate the heavy object from static to close to the rated operating speed, thereby further improving the overall efficiency of the gravity energy storage system.

[0006] The utility model is realized by the following technical solutions:

[0007] A gravity energy storage power recovery system based on hydraulic compressed air energy storage, comprising a gravity energy storage system and a kinetic energy recovery system;

[0008] The gravity energy storage system is used to absorb the surplus power of the power grid when the load demand of the power grid is low. The electric motor is used to lift the vertical height of the weight block. When the load demand of the power grid is high, the weight block is lowered to release the gravity potential energy to drive the generator to generate electricity to supplement the power gap of the power grid. The gravity energy storage system transfers part of the kinetic energy of the weight block to the kinetic energy recovery system during the shutdown stage when the weight block is lifted and the energy is released.

[0009] The kinetic energy recovery system is used to absorb the waste kinetic energy and a small amount of gravitational potential energy transmitted by the gravity energy storage system during the shutdown stage when the gravity energy storage system finishes lifting the heavy object block and releasing the energy, and convert them into liquid compressed air energy for storage; in the startup stage when the heavy object block starts to be lifted and the energy release begins, the liquid compressed air energy is released to accelerate the heavy object block to a speed close to the rated operating speed of the heavy object block, thereby realizing the reuse of kinetic energy recovery.

[0010] A further improvement of the utility model is that the gravity energy storage system includes a generator motor, a first gearbox, an energy storage drive clutch, a drum, a wire rope, a heavy object and a brake device;

[0011] The generator motor is connected with the energy storage drive clutch, the energy storage drive clutch, the brake device and the drum in sequence through the first gearbox by using the rotating shaft; the wire rope is wound on the drum, and the free end of the wire rope is connected to the heavy object.

[0012] A further improvement of the utility model is that the generator motor has a generator function and a motor function at the same time.

[0013] A further improvement of the utility model is that the kinetic energy recovery system includes a kinetic energy recovery clutch, a second gearbox, a variable pump / turbine, a relief valve, a liquid compressed air accumulator and a fuel tank;

[0014] One side of the drum is connected to the kinetic energy recovery clutch and the second gearbox in sequence by a rotating shaft, and the outlet of the second gearbox is connected to the variable pump / turbine; the liquid compressed air accumulator interface is connected to the variable pump / turbine by an oil pipeline and connected to the oil tank, the overflow valve inlet is connected from the liquid compressed air accumulator interface oil pipeline, and the overflow valve outlet is connected to the oil tank.

[0015] A further improvement of the utility model is that both the energy storage drive clutch and the kinetic energy recovery clutch have a bidirectional power transmission function and an interlocking function.

[0016] A further improvement of the utility model is that the variable pump / turbine has the pump functions of conveying and pressurizing during the energy absorption process of the kinetic energy recovery system.

[0017] A further improvement of the utility model is that the variable displacement pump / turbine has a turbine driving function during the energy release process.

[0018] Compared with the prior art, the utility model has at least the following beneficial technical effects:

[0019] A liquid compressed air device is used as a kinetic energy recovery system and combined with a gravity energy storage system to realize gravity energy storage. During the energy storage stage, when the weight block is lifted and the energy release is completed, part of the kinetic energy of the weight block is transferred to the kinetic energy recovery system to store the energy in the form of liquid compressed air potential energy, rather than all of it being braked by the brake system and dissipated and wasted in the form of heat.

[0020] Furthermore, the utility model realizes that the gravity energy storage system releases the potential energy of the liquid compressed air stored in the kinetic energy recovery system at the beginning stage of energy release, that is, the startup stage when the weight block starts to be lifted and the energy release starts, so as to accelerate the weight block to a speed close to the rated operating speed of the weight block, thereby realizing the recovery and reuse of kinetic energy, thereby effectively reducing the energy consumption during the startup process of the gravity energy storage system.

[0021] Furthermore, an interlocking energy storage drive clutch and kinetic energy recovery clutch are used to achieve close workflow coordination between the kinetic energy recovery system and the gravity energy storage system during the energy absorption process and the start and end stages of energy release, thereby achieving continuity and stability in system operation.

[0022] Furthermore, a variable pump / turbine device is used so that the kinetic energy recovery system has a pump function in the process of absorbing energy and a turbine drive function in the process of releasing energy, and the system connection is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of a gravity energy storage kinetic energy recovery system based on liquid compressed air energy storage described in an example of the utility model.

[0024] Description of reference numerals:

[0025] 1-generator motor, 2-energy storage drive clutch, 3-reel, 4-kinetic energy recovery clutch, 5-variable pump / turbine, 6-overflow valve, 7-liquid compressed air accumulator, 8-oil tank, 9-wire rope, 10-heavy object, 11-first gearbox, 12-second gearbox, 13-brake device. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below in conjunction with specific implementation methods, which are intended to explain the present invention rather than to limit it.

[0027] like Figure 1 As shown, the utility model provides a gravity energy storage power recovery system based on hydraulic compressed air energy storage, including a gravity energy storage system and a kinetic energy recovery system.

[0028] Among them, the gravity energy storage system includes a generator motor 1, a first gearbox 11, an energy storage drive clutch 2, a drum 3, a wire rope 9, a heavy object 10, a brake device 13 and other equipment; the kinetic energy recovery system includes a kinetic energy recovery clutch 4, a second gearbox 12, a variable pump / turbine 5, a relief valve 6, a liquid compressed air accumulator 7 and an oil tank and other equipment.

[0029] The above-mentioned generator motor 1 has a power generation function and also a motor function; the energy storage drive clutch 2 and the kinetic energy recovery clutch 4 both have a two-way power transmission function and an interlocking function, that is, when the energy storage drive clutch 2 is disengaged, the kinetic energy recovery clutch 4 is engaged at the same time, and when the energy storage drive clutch 2 is engaged, the kinetic energy recovery clutch 4 is disengaged at the same time; the variable pump / turbine 5 has a conveying and pressurizing pump function during the energy absorption process of the kinetic energy recovery system, and has a turbine drive function during the energy release process.

[0030] The connection methods of each device are as follows:

[0031] The generator motor 1 is connected to the energy storage drive clutch 2, the energy storage drive clutch 2, the brake device 13, and the drum 3 in sequence through the first gearbox 11 by means of a rotating shaft; the wire rope 9 is wound around the drum 3, and the free end is connected to the heavy object 10;

[0032] One side of the reel 3 is connected to the kinetic energy recovery clutch 4 and the second gearbox 12 in sequence by a rotating shaft, and the outlet of the second gearbox 12 is connected to the variable pump / turbine 5; the interface of the liquid compressed air accumulator 7 is connected to the variable pump / turbine 5 by an oil pipeline, and is connected to the oil tank 8, the inlet of the overflow valve 6 is connected from the oil pipeline of the interface of the liquid compressed air accumulator 7, and the outlet of the overflow valve 6 is connected to the oil tank 8.

[0033] The energy absorption working process of the kinetic energy recovery system is as follows:

[0034] When the weight block 10 of the gravity energy storage system is in the lifting and energy release stage, the energy storage drive clutch 2 is in the engaged state, the kinetic energy recovery clutch 4 is in the disengaged state, and the variable pump / turbine 5 is in the oil pump working state;

[0035] At the beginning of the shutdown phase when the gravity energy storage system has finished lifting the heavy object and releasing the energy, the energy storage drive clutch 2 is switched to the disengaged state, and the kinetic energy recovery clutch 4 is switched to the engaged state. The reel 3 drives the variable pump / turbine 5 through the clutch 4 and the gearbox 12, and drives the variable pump / turbine 5 to transport the oil in the oil tank 8 to the liquid compressed air accumulator 7 to increase its liquid level and compressed air pressure, store energy, and realize kinetic energy recovery; due to the large damping of the kinetic energy recovery system, the reel 3 and the heavy object 10 are quickly decelerated during the kinetic energy recovery and storage process; if the liquid compressed air accumulator 7 is over-pressurized, the overflow valve 6 is automatically opened, and the working oil overflows from the compressed air accumulator 7 to the oil tank 8;

[0036] When the reel 3 and the weight 10 are unable to drive the variable displacement pump / turbine 5 to normally deliver oil to the liquid compressed air accumulator 7, the gravity energy storage brake device 13 brakes to stop the reel 3 and the weight 10.

[0037] The energy release working process of the kinetic energy recovery system is:

[0038] When the weight block 10 of the gravity energy storage system is in a stationary state, that is, before the energy storage is increased or released, the energy storage drive clutch 2 is in a disengaged state, the kinetic energy recovery clutch 4 is in an engaged state, the brake device 13 is in a braking state, and the variable pump / turbine 5 is switched to a turbine working mode;

[0039] After the energy storage or release of the gravity energy storage system begins, the brake device 13 switches to the released state, and at the same time, the compressed air in the liquid compressed air accumulator 7 drives the working oil into the variable pump / turbine 5 to work, driving the reel 3 and the heavy object 10 to start accelerating;

[0040] When the liquid compressed air accumulator 7 can no longer drive the drum 3 and the heavy object 10 to continue accelerating, the energy storage drive clutch 2 switches to the engaged state, while the kinetic energy recovery clutch 4 switches to the disengaged state, and the generator motor 1 enters the working state to generate electricity or drive the drum 3 to continue working.

[0041] The utility model can realize that when the load demand of the power grid is low, the gravity energy storage system consumes the surplus power of the power grid, and uses the motor to increase the vertical height of the weight block. When the load demand of the power grid is high, the weight block is lowered to release the gravity potential energy to drive the generator to generate electricity to supplement the power gap of the power grid. The gravity energy storage system transfers part of the kinetic energy of the weight block to the kinetic energy recovery system during the shutdown stage when the weight block is lifted and the energy is released.

[0042] During the shutdown stage of the gravity energy storage system when the weight block is lifted and the energy release is completed, the kinetic energy recovery system absorbs the waste kinetic energy and a small amount of gravitational potential energy transmitted by the gravity energy storage system, and converts them into liquid compressed air energy for storage; during the startup stage when the weight block is lifted and the energy release begins, the liquid compressed air energy is released to accelerate the weight block to a speed close to the rated operating speed of the weight block, thereby realizing the reuse of kinetic energy recovery.

[0043] The above description is only a preferred specific implementation method of the utility model, and does not limit the patent scope of the utility model. Any use of the contents of the utility model specification and drawings directly or indirectly in other related technical fields is also included in the patent protection scope of the utility model.

Claims

1. A gravity energy storage power recovery system based on hydraulic compressed air energy storage, characterized in that: Including gravity energy storage system and kinetic energy recovery system; The gravity energy storage system comprises a generator motor (1), a first gearbox (11), an energy storage drive clutch (2), a drum (3), a steel wire rope (9), a heavy object (10) and a brake device (13); the generator motor (1) is connected to the energy storage drive clutch (2), the energy storage drive clutch (2), the brake device (13) and the drum (3) in sequence through a rotating shaft through the first gearbox (11); the steel wire rope (9) is wound around the drum (3), and the free end of the steel wire rope (9) is connected to the heavy object (10); The kinetic energy recovery system comprises a kinetic energy recovery clutch (4), a second gearbox (12), a variable pump / turbine (5), a liquid compressed air accumulator (7) and an oil tank; one side of the reel (3) is connected to the kinetic energy recovery clutch (4) and the second gearbox (12) in sequence by means of a rotating shaft, and the outlet of the second gearbox (12) is connected to the variable pump / turbine (5); the interface of the liquid compressed air accumulator (7) is connected to the variable pump / turbine (5) by means of an oil pipeline, and is also connected to the oil tank (8).

2. A gravity energy storage power recovery system based on hydraulic compressed air energy storage according to claim 1, characterized in that: The generator motor (1) has a generator function and a motor function at the same time.

3. A gravity energy storage power recovery system based on hydraulic compressed air energy storage according to claim 1, characterized in that: The kinetic energy recovery system also includes a relief valve (6), the inlet of the relief valve (6) is connected to an oil pipeline of an interface of a liquid compressed air accumulator (7), and the outlet of the relief valve (6) is connected to an oil tank (8).

4. A gravity energy storage power recovery system based on hydraulic compressed air energy storage according to claim 1, characterized in that: The energy storage drive clutch (2) has a bidirectional power transmission function and an interlocking function.

5. A gravity energy storage power recovery system based on hydraulic compressed air energy storage according to claim 1, characterized in that: The kinetic energy recovery clutch (4) has a bidirectional power transmission function and an interlocking function.

6. A gravity energy storage power recovery system based on hydraulic compressed air energy storage according to claim 1, characterized in that: The variable displacement pump / turbine (5) has the pump functions of conveying and boosting during the energy absorption process of the kinetic energy recovery system.

7. A gravity energy storage power recovery system based on hydraulic compressed air energy storage according to claim 1, characterized in that: The variable displacement pump / turbine (5) has the function of turbine drive during the energy release process.

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