阅读说明：本技术 一种模块化可调功率易扩容的重力储能系统 (Modular gravity energy storage system with adjustable power and easy capacity expansion ) 是由 薛志恒 贾晨光 邢乐强 杨可 何欣欣 陈会勇 赵杰 王伟锋 张朋飞 孟勇 王兴 于 2021-06-08 设计创作，主要内容包括：本发明公开了一种模块化可调功率易扩容的重力储能系统,包括发电/电动一体机和N个单组储能/发电模块；所述的单组储能/发电模块包括单个钢丝绳索卷轴筒单元、M-i个储能单元、1根钢丝绳索、1组钢丝绳索末端滑轮支撑装置单元及钢丝绳末端固定及受力监测装置单元；所述M-i个储能单元首尾相接、连续排列,M-i个储能单元布置在单个钢丝绳索卷轴筒单元的一侧且固定在储能塔模块地面上,M-i个储能单元排列末端的地面位置布置钢丝绳索末端滑轮支撑装置单元及钢丝绳末端固定及受力监测装置单元。本发明的发电过程具有输出功率稳定、可调的特点,系统储能容量及发电功率易实现扩容,系统安全性高。(The invention discloses a modularized power-adjustable and capacity-expandable gravity energy storage system, which comprises a power generation/electric integrated machine and N single-group energy storage/power generation modules; the single-group energy storage/power generation module comprises a single steel wire rope reel drum unit and an M i The energy storage unit, 1 steel wire rope, 1 group of steel wire rope tail end pulley supporting device units and the steel wire rope tail end fixing and stress monitoring device unit are arranged; the M is i The energy storage units are connected end to end and arranged continuously, M i The energy storage units are arranged at one side of the single steel wire rope reel drum unit and fixed on the ground of the energy storage tower module, M i The ground position of the tail end of the energy storage unit arrangement is provided with a steel wire rope tail end pulley supporting device unit and a steel wire rope tail end fixing and stress monitoring device unit. The power generation process of the invention has the characteristics of stable and adjustable output power, the capacity expansion of the system energy storage capacity and the power generation power is easy to realize, and the system safety is high.)

1. A modularized power-adjustable and capacity-expandable gravity energy storage system is characterized by comprising a power generation/electric integrated machine (1) and N single-group energy storage/power generation modules (13);

the single group of energy storage/power generation modules (13) comprises a single wire rope reel drum unit (14) and an M_iThe energy storage unit (16), 1 steel wire rope (7), 1 group of steel wire rope tail end pulley supporting device unit (5) and the steel wire rope tail end fixing and stress monitoring device unit (9);

the M is_iThe energy storage units (16) are arranged end to end and are arranged in series, M_iThe energy storage units (16) are arranged on one side of the single wire rope reel drum unit (14) and fixed on the energy storage tower module ground (10), M_iThe ground position of the tail end of the energy storage unit (16) array is provided with a steel wire rope tail end pulley supporting device unit (5) and a steel wire rope tail end fixing and stress monitoring device unit (9).

2. The modular adjustable power expandable gravity energy storage system according to claim 1, wherein the single wire rope reel drum unit (14) comprises a wire rope reel drum support device (3), a wire rope reel drum (2) and a rotating shaft (17);

the rotating shaft (17) penetrates through the steel wire rope reel barrel (2) and is fixed and supported by the steel wire rope reel barrel supporting device (3);

a clutch is arranged between the rotating shaft (17) and the steel wire rope reel drum (2), is a part of the steel wire rope reel drum (2) and is used for realizing the engagement and disconnection of the two-way rotation between the steel wire rope reel drum (2) and the rotating shaft (17);

couplings are arranged on two sides of the rotating shaft (17) and used for realizing connection between adjacent steel wire rope reel drum units (14), so that the steel wire rope reel drum units (14) realize expansibility.

3. The modular adjustable power expandable gravity energy storage system according to claim 1, wherein the energy storage unit (16) comprises a unit energy storage tower (15), a weight box (6), a weight box movable pulley block (12), an energy storage tower module top platform fixed pulley block and support device (4) and an energy storage unit rain shelter (8);

the number M of energy storage units (16)_iNot less than 1, no upper limit of theoretical amount;

the number M of each energy storage unit (16) in the N single-group energy storage/power generation modules (13)_iCan be different, and the quantity M of the energy storage units (16) in any single-group energy storage/power generation module (13) can be expanded and increased at any time after the unit is put into operation_iThe energy storage capacity of the unit is increased;

g is the same for all the weight boxes (6), the weight boxes (6) are placed inside the unit system energy storage tower (15), and a weight box movable pulley block (12) is arranged in the center of the top of each weight box (6);

the energy storage working medium materials filled in the weight box (6) can be sand, cement, metal and other solid materials with stable chemical properties and liquid materials with stable chemical properties, and the larger the density of the working medium materials is, the larger the energy storage capacity of the system is;

the effective lifting height H of the weight of each unit energy storage tower (15)_iMay be the same or different;

an energy storage unit rain-proof shed (8) is arranged at the top of the unit energy storage tower (15);

the lower layer of the energy storage unit rain-proof shed (8) is provided with an energy storage tower module top platform fixed pulley block and a supporting device (4), and the energy storage tower module top platform fixed pulley block and the supporting device (4) comprise fixed pulleys and a bearing system.

4. The modular power-adjustable and capacity-expandable gravity energy storage system as claimed in claim 1, wherein the steel wire rope end pulley support device unit (5) and the steel wire rope end fixing and stress monitoring device unit (9) are used for monitoring the tension of the steel wire rope (7), and have functions of alarming, fault diagnosis and operation shutdown protection interlocking, and the steel wire rope (7) end is fixed.

5. The modular power-adjustable and capacity-expandable gravity energy storage system as claimed in claim 1, wherein one end of the steel wire rope (7) is fixed on the steel wire rope end fixing and stress monitoring device unit (9) of the energy storage/power generation module (13), and sequentially passes through the steel wire rope end pulley supporting device unit (5) of the energy storage/power generation module (13) and the M-shaped pulley supporting device units arranged in tandem to pass through_iThe energy storage tower module top platform fixed pulley block of each energy storage unit (16), the fixed pulley block of each supporting device unit (4) and the heavy case movable pulley block (12) finally penetrate through the energy storage tower module top platform fixed pulley block of each tail end energy storage unit (16) and the fixed pulley block of each supporting device unit (4) and then are connected to the steel wire rope reel drum (2) of the single steel wire rope reel drum unit (14) in the energy storage/power generation module (13).

6. The modular adjustable power and expandable gravity energy storage system according to claim 1, wherein the number of the single group of energy storage/power generation modules (13) and the number N of the steel wire ropes (7) are even and are evenly distributed on two sides of the rotating shaft of the integrated power generation/motor machine (1); after the unit is put into operation, the capacity of the unit can be expanded at any time, the number N of the single-group energy storage/power generation modules (13) can be increased, and the energy storage capacity and the external output maximum power of the unit are increased accordingly.

7. The modular adjustable power expandable gravity energy storage system according to claim 1, wherein the gravity energy storage system has the following characteristics during stable operation of energy storage or power generation:

(a) no matter the number M of the energy storage units (16) in a single group_iThe theoretical tension on a single steel wire rope (7) is always 0.5G under the condition of neglecting the resistance of the pulley block;

(b) assuming that the rotation angular velocity of the generator is omega, the maximum external output power of the energy storage system in the power generation process is shown in the formula (1), and at the moment, all the energy storage/power generation modules (13) release energy at the same time; the minimum output power of the energy storage unit is shown in formula (2), and only 1 group of energy storage/power generation modules 13 release energy at the moment;

in the formula: p_maxOutputting maximum power, kW, to the outside for the energy storage system; n is the number of the single group of energy storage/power generation modules 13; r is the radius of the steel wire rope reel barrel, m; omega is the rated rotation speed of the generator, r/min; g is the weight of a single weight, N;

in the formula: p_minOutputting the minimum power, kW, to the outside for the energy storage system; n is the number of the single group of energy storage/power generation modules 13; r is the radius of the steel wire rope reel barrel, m; omega is the rated rotation speed of the generator, r/min; g is the weight of a single weight, N;

(c) assuming that the generator speed is ω, the total energy storage maximum capacity of the energy storage system is shown as formula (3):

in the formula: w_totThe maximum energy storage capacity of the energy storage system, kWh; n is the number of the single group of energy storage/power generation modules 13; g is the weight of a single weight, N, M_iThe number of the energy storage units (16) of each group of energy storage/generation modules (13) is one; h_iAnd manufacturing an energy storage tower weight for each unit of each group of energy storage/power generation module to effectively lift the height m.

Technical Field

The invention relates to the technical field of gravity energy storage and power generation, in particular to a modularized gravity energy storage system with adjustable power and easy capacity expansion.

Background

The output power of the wind power, solar energy and other new energy power generation systems is limited by objective conditions, and the systems have randomness, intermittency and instability. And a large amount of new energy is installed and expanded, so that the time supply and demand balance difference between the power generation side and the power grid user side is enlarged, and the instability of power grid operation is increased.

The existing mainstream energy storage systems, such as pumped storage, battery energy storage, compressed air energy storage and the like, can find that the existing energy storage systems have certain defects or have low efficiency, such as compressed air energy storage and pumped storage; or short cycle life such as battery storage; or the environment is not environment-friendly enough, such as damage of pumped storage power stations to the environment and battery energy storage; or the cost is higher in the existing modes; or the requirements on the geographical position are severe, such as pumped storage and large-scale compressed air storage. This results in the existing energy storage systems being only suitable for small-scale experimental exploration, but not for large-scale application.

At present, the main type of foreign gravity energy storage systems is based on cement block working media or rail type, and a complex transshipment stacking mechanism is adopted, so that the complexity and the loss of the system are increased, and the capacity expansion of the energy storage system is difficult. In China, the gravity energy storage is still in the theoretical research stage, and the development of a low-cost and easily-expandable gravity energy storage system has important significance.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention aims to provide a modularized power-adjustable and easily-expandable gravity energy storage system, wherein any chemically stable solid material such as sand, stone, cement, metal and the like and any chemically stable liquid material can be used as the working medium to participate in the energy storage and power generation processes, the power generation process has the characteristics of stable and adjustable output power, the capacity expansion of the system energy storage capacity and the power generation power is easily realized, and the system safety is high.

In order to achieve the purpose, the invention adopts the technical scheme that:

a modularized power-adjustable and capacity-expandable gravity energy storage system comprises a power generation/electric integrated machine 1 and N single-group energy storage/power generation modules 13;

the single group of energy storage/power generation modules 13 comprises a single wire rope reel barrel unit 14, M_iThe energy storage unit 16, 1 steel wire rope 7, 1 group of steel wire rope tail end pulley supporting device unit 5 and the steel wire rope tail end fixing and stress monitoring device unit 9;

the M is_iThe energy storage units 16 are arranged end to end and are arranged in series, M_iThe energy storage units 16 are arranged on one side of the single wire rope reel unit 14 and fixed on the energy storage tower module ground 10, M_iThe ground position of the tail end of the energy storage unit 16 is provided with a steel wire rope tail end pulley supporting device unit 5 and a steel wire rope tail end fixing and stress monitoring device unit 9.

The single wire rope reel barrel unit 14 comprises a wire rope reel barrel supporting device 3, a wire rope reel barrel 2 and a rotating shaft 17;

the rotating shaft 17 penetrates through the steel wire rope reel barrel 2 and is fixed and supported by the steel wire rope reel barrel supporting device 3;

a clutch is arranged between the rotating shaft 17 and the steel wire rope reel drum 2, is a part of the steel wire rope reel drum 2 and is used for realizing the engagement and disconnection of the two-way rotation between the steel wire rope reel drum 2 and the rotating shaft 17;

couplings are arranged on two sides of the rotating shaft 17 and used for realizing connection between adjacent steel wire rope reel drum units 14, so that the expansibility of the steel wire rope reel drum units 14 is realized, and the capacity expansion can be realized by adding one group of steel wire rope reel drum units 14 only by connecting the couplings and increasing the energy storage capacity and the power generation capacity.

The energy storage unit 16 comprises a unit energy storage tower 15, a weight box 6, a weight box sliding pulley group 12, an energy storage tower module top platform fixed pulley group and supporting device 4 and an energy storage unit rain shed 8;

number M of energy storage units 16_iNot less than 1, no upper limit of theoretical amount;

the number M of each energy storage unit 16 in the N single-group energy storage/power generation modules 13_iDifferent, after the unit is put into operation, the quantity M of the energy storage units 16 in any single-unit energy storage/power generation module 13 can be expanded and increased at any time_iThe energy storage capacity of the unit is increased;

g is the same for all the weight boxes 6, the weight boxes 6 are placed inside the unit energy storage tower 15, and a weight box movable pulley block 12 is arranged in the center of the top of each weight box 6;

the energy storage working medium material filled in the weight box 6 can be sand, cement, metal and other solid materials with stable chemical properties and liquid materials with stable chemical properties, and the larger the density of the working medium material is, the larger the energy storage capacity of the system is;

the effective lifting height H of each unit energy storage tower 15 weight_iMay be the same or different;

an energy storage unit rain-proof shed 8 is arranged at the top of the unit energy storage tower 15;

the lower layer of the energy storage unit rain-proof shed 8 is provided with an energy storage tower module top platform fixed pulley block and a supporting device 4, and the energy storage tower module top platform fixed pulley block and the supporting device 4 comprise fixed pulleys and a bearing system.

The steel wire rope tail end pulley supporting device unit 5 and the steel wire rope tail end fixing and stress monitoring device unit 9 are used for monitoring the tensile force of the steel wire rope 7, have the functions of alarming, fault diagnosis and operation shutdown protection interlocking, and fix the tail end of the steel wire rope 7.

One end of the steel wire rope 7 is fixed on the steel wire rope tail end fixing and stress monitoring device unit 9 of the energy storage/power generation module 13, sequentially passes through the steel wire rope tail end pulley supporting device unit 5 of the energy storage/power generation module 13 and passes through the M arranged in front and back_iThe energy storage tower module top platform fixed pulley block of each energy storage unit 16, the fixed pulley block of the supporting device unit 4 and the heavy box movable pulley block 12 finally pass through the energy storage tower module top platform fixed pulley block of the tail end energy storage unit 16 and the fixed pulley block of the supporting device unit 4 and then are connected to the steel wire rope reel barrel 2 of the single steel wire rope reel barrel unit 14 in the energy storage/power generation module 13.

The number of the single group of energy storage/power generation modules 13 and the number N of the steel wire ropes 7 are even numbers and are evenly distributed on two sides of a rotating shaft of the power generation/electric integrated machine 1; after the unit is put into operation, the capacity of the unit can be expanded at any time to increase the number N of the single-group energy storage/power generation modules 13, and the energy storage capacity and the external output maximum power of the unit are increased accordingly.

The gravity energy storage system has the following characteristics in the stable operation process of energy storage or power generation:

(a) no matter the number M of the energy storage units 16 in a single group_iThe theoretical tension on the single steel wire rope 7 is always 0.5G under the condition of neglecting the resistance of the pulley block;

(b) assuming that the rotational angular velocity of the generator is ω, the maximum external output power of the energy storage system during the power generation process is shown in formula (1), and at this time, all the energy storage/power generation modules 13 release energy at the same time; the minimum output power of the energy storage unit is shown in formula (2), and only 1 group of energy storage/power generation modules 13 release energy at the moment;

in the formula: p_maxOutputting maximum power, kW, to the outside for the energy storage system; n is single group energy storageNumber of power generation modules 13; r is the radius of the steel wire rope reel barrel, m; omega is the rated rotation speed of the generator, r/min; g is the weight of a single weight, N;

in the formula: p_minOutputting the minimum power, kW, to the outside for the energy storage system; n is the number of the single-group energy storage/power generation modules 13; r is the radius of the steel wire rope reel barrel, m; omega is the rated rotation speed of the generator, r/min; g is the weight of a single weight, N;

(c) assuming that the generator speed is ω, the total energy storage maximum capacity of the energy storage system is shown as formula (3):

in the formula: w_totThe maximum energy storage capacity of the energy storage system, kWh; n is the number of the single group of energy storage/power generation modules 13; g is the weight of a single weight, N. M_iThe number of the energy storage units 16 for each group of energy storage/generation modules 13; h_iAnd manufacturing an energy storage tower weight for each unit of each group of energy storage/power generation module to effectively lift the height m.

The invention has the beneficial effects that:

(1) through the design of the unit modular gravity energy storage system, the complicated transshipment stacking mechanism design of the gravity energy storage system in a stacking mode is avoided, and the system configuration and operation are simpler and more reliable;

(2) no matter how many energy storage modules are added, the stress of the steel wire rope is always kept constant in the energy storage and power generation processes, and the safety of the system is greatly improved;

(3) the load output in the generating process of the unit is stable. In the power generation process, the torque applied to the generator shaft is kept constant at all times, so that the power generation load can be stable;

(4) the energy storage working media are diversified, sand, stone, metal, liquid and the like can be used as the energy storage working media, and the energy storage investment cost can be greatly reduced;

(5) the energy storage power generation system can be built in any place, and the desert edge, the mountain side, the rural useless land and the like can be used as the site for building the energy storage power generation system.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a side view of the present invention.

FIG. 3 is a top view of the present invention.

Fig. 4 is a schematic view of the overall structure of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 1 to 4, the modular power-adjustable and capacity-expandable gravity energy storage system mainly includes a power generation/electric integration machine 1 and N single-group energy storage/power generation modules 13, where N in the drawing of this example is 4.

The single set of energy storage/generation modules 13 comprises: single wire rope reel unit 14, M_iAn energy storage unit 16, 1 steel wire rope 7, 1 group of steel wire rope tail end pulley supporting device units 5, a steel wire rope tail end fixing and stress monitoring device unit 9 and the like, wherein M in the drawing of the example_iAre all 4.

For a single set of energy storage/generation modules 13, M_iThe energy storage units 16 are arranged end to end and are arranged in series, are arranged on one side of the single wire rope reel drum unit 14 and are fixed on the ground 10 of one energy storage tower module.

The steel wire rope tail end pulley supporting device unit 5 and the steel wire rope tail end fixing and stress monitoring device unit 9 are arranged at M_iThe ground location of the end of the array of energy storage cells 16.

The single wire rope reel unit 14 includes: a steel wire rope reel barrel supporting device 3, a steel wire rope reel barrel 2 and a rotating shaft 17.

The rotating shaft 17 penetrates through the wire rope reel barrel 2 and is fixed and supported by the wire rope reel barrel supporting device 3.

A clutch is arranged between the rotating shaft 17 and the steel wire rope reel barrel 2, the clutch is a part of the steel wire rope reel barrel 2, and the engagement and the disconnection of the two-way rotation between the steel wire rope reel barrel 2 and the rotating shaft 17 can be realized.

The shaft couplings are arranged on two sides of the rotating shaft 17, and the connection between the adjacent steel wire rope reel drum units 14 can be realized, so that the expansibility of the steel wire rope reel drum units 14 is realized, and the capacity expansion can be realized by adding one group of steel wire rope reel drum units 14 only by connecting the shaft couplings and storing energy capacity and generating power.

The energy storage unit 16 includes: the device comprises a unit energy storage tower 15, a weight box 6, a weight box movable pulley block 12, an energy storage tower module top platform fixed pulley block and supporting device 4 and an energy storage unit rain-proof shed 8.

Number M of energy storage units 16_iNot less than 1, and no upper limit on the theoretical amount.

The number M of each energy storage unit 16 in the N single-group energy storage/power generation modules 13_iDifferent, after the unit is put into operation, the quantity M of the energy storage units 16 in any single-unit energy storage/power generation module 13 can be expanded and increased at any time_iThe energy storage capacity of the unit is increased.

All the weight boxes 6 are same in weight G, the weight boxes 6 are placed inside the unit energy storage tower 15, and the center of the top of each weight box 6 is provided with a weight box movable pulley block 12.

The energy storage working medium material filled in the weight box 6 can be sand, cement, metal and other solid materials with stable chemical properties and liquid materials with stable chemical properties, and the larger the density of the working medium material is, the larger the energy storage capacity of the system is.

Effective lifting height H of each unit energy storage tower 15 weight_iMay be the same or different.

An energy storage unit rain-proof shed 8 is arranged at the top of the unit energy storage tower 15.

The lower layer of the energy storage unit rainproof shed 8 at the top of the unit energy storage tower 15 is provided with an energy storage tower module top platform fixed pulley block and supporting device 4 which comprises a fixed pulley and a bearing system.

The steel wire rope tail end pulley supporting device unit 5 and the steel wire rope tail end fixing and stress monitoring device unit 9 have the functions that: the tension of the steel wire rope 7 is monitored, and the steel wire rope tension monitoring device has the functions of alarming, fault diagnosis and operation shutdown protection interlocking and is used for fixing the tail end of the steel wire rope 7.

One end of the steel wire rope 7 is fixed on the steel wire rope tail end fixing and stress monitoring device unit 9 of the energy storage/power generation module 13, sequentially passes through the steel wire rope tail end pulley supporting device unit 5 of the energy storage/power generation module 13 and passes through the M arranged in front and back_iThe energy storage tower module top platform fixed pulley block of each energy storage unit 16, the fixed pulley block of the supporting device unit 4 and the heavy box movable pulley block 12 finally pass through the energy storage tower module top platform fixed pulley block of the tail end energy storage unit 16 and the fixed pulley block of the supporting device unit 4 and then are connected to the steel wire rope reel barrel 2 of the single steel wire rope reel barrel unit 14 in the energy storage/power generation module 13.

The number of the single group of energy storage/power generation modules 13 and the number N of the steel wire ropes 7 are even numbers and are evenly distributed on two sides of a rotating shaft of the power generation/electric integrated machine 1; after the unit is put into operation, the capacity of the unit can be expanded at any time to increase the number N of the single-group energy storage/power generation modules 13, and the energy storage capacity and the external output maximum power of the unit are increased accordingly.

In the stable operation process of energy storage or power generation, the following characteristics are provided:

(a) no matter the number M of the energy storage units 16 in a single group_iThe theoretical tension on the single steel wire rope 7 is always 0.5G under the condition of neglecting the resistance of the pulley block;

(b) assuming that the rotational angular velocity of the generator is ω, the maximum external output power of the energy storage system during the power generation process is shown in formula (1), and at this time, all the energy storage/power generation modules 13 release energy at the same time; the minimum output power of the energy storage unit is shown in formula (2), and only 1 group of energy storage/power generation modules 13 release energy at the moment;

in the formula: p_maxOutputting maximum power, kW, to the outside for the energy storage system; n is the number of the single-group energy storage/power generation modules 13; r is a steel wire ropeRadius of the cable reel drum, m; omega is the rated rotation speed of the generator, r/min; g is the weight of a single weight, N.

In the formula: p_minOutputting the minimum power, kW, to the outside for the energy storage system; n is the number of the single-group energy storage/power generation modules 13; r is the radius of the steel wire rope reel barrel, m; omega is the rated rotation speed of the generator, r/min; g is the weight of a single weight, N.

(c) Assuming that the generator speed is ω, the total energy storage maximum capacity of the energy storage system is shown as formula (3):

in the formula: w_totThe maximum energy storage capacity of the energy storage system, kWh; n is the number of the single group of energy storage/power generation modules 13; g is the weight of a single weight, N. M_iThe number of the energy storage units 16 for each group of energy storage/generation modules 13; h_iAnd manufacturing an energy storage tower weight for each unit of each group of energy storage/power generation module to effectively lift the height m.

The energy storage system can obviously change the mode of synchronously completing power production, transmission and use, realizes the staggered utilization of electric energy in the time dimension, and is a key factor for the rapid development and the effective utilization of new energy.

Compared with the existing energy storage technology, the emerging gravity energy storage system can theoretically realize high efficiency, environmental protection, low cost, good expansibility and no region limitation, the efficiency can reach more than 90% theoretically, the problem of environmental pollution does not exist, the geographical position adaptability is strong, and the cost after large-scale application can be obviously reduced. Therefore, the gravity energy storage technology is an effective direction for solving the problem of stable operation of a power grid under the new energy power generation condition in the future.

The working principle of the invention is as follows:

(1) in the energy storage process, the power generation/electric integration machine 1 is positionedThe motor working mode drives the wire rope reel drum 2 in the wire rope reel drum unit 14 to rotate, the steel wire rope 7 is continuously wound on the wire rope reel drum 2, the pulling force on the steel wire rope 7 is the gravity of a single weight box 6, the weight box 6 is connected with the pulling force of the steel wire rope 7 on the weight box movable pulley block 12, and the height is continuously lifted from the ground until the design height H is reached_iThe system stops the energy storage process. The system stores a lot of gravitational potential energy, since a lot of heavy boxes 6 with large mass are lifted to a certain vertical height during the energy storage.

(2) In the power generation process, the weight box 6 moves downwards under the action of gravity, in the uniform-speed movement process, the tension of the steel wire rope 7 is kept unchanged, the steel wire rope reel 2 and the power generation/electric integrated machine 1 are driven to rotate, at the moment, the power generation/electric integrated machine 1 is in a power generation mode, the gravitational potential energy of a large number of weight boxes 6 is continuously released, and the gravitational potential energy is converted into electric energy through the power generation/electric integrated machine 1 to be output.

Examples illustrate that:

as shown in table 1, the basic design parameters of the modular adjustable power expandable gravity energy storage system shown in fig. 1 are shown.

In this design system, the length x width x height of the weight box is: the effective lifting average height H of each unit energy storage tower weight is 100m, the number of the energy storage/power generation modules is 4, and the number of the energy storage units of a single group of energy storage/power generation modules is 4.

In the example shown in fig. 1, the calculation result shows that the floor area of the energy storage system is 2041m2, the maximum power output by the energy storage system is 15.268MW when the weight is sand, the maximum power output by the energy storage system is 22.902MW when the weight is cement block, and the maximum power output by the energy storage system is 60.309MW when the weight is sand. The rated rotation speed of the generator is 300rpm, the total energy storage capacity is 2.12MW when the weight is sand, the total energy storage capacity is 3.18MW when the weight is a cement block, and the total energy storage capacity is 8.37MW when the weight is a cement block.

By expanding the number of the energy storage/generation modules and the number of the energy storage units in the single group of energy storage/generation modules, the energy storage capacity of the unit and the external output maximum power of the energy storage system can be obviously increased.

The drawings are only for purposes of illustrating the invention and are not to be construed as limiting the scope of the invention, which is intended to be covered by the claims, since certain insubstantial modifications and adaptations of the invention may occur to those skilled in the art in light of the foregoing description.

TABLE 1 basic design parameters of modularized gravity energy storage system with stable and adjustable output power and expandable power and capacity