A photovoltaic power generation and energy storage system for coal mining subsidence areas

Abstract

This utility model discloses a photovoltaic power generation and energy storage system for coal mining subsidence areas, comprising: a booster unit, an energy storage unit, a control unit, and multiple sets of photovoltaic power generation units; the photovoltaic power generation units are connected to the booster unit, the energy storage units are connected to the booster unit, and the booster unit is connected to the power grid; the control unit is connected to the photovoltaic power generation units and the energy storage units. Constructing a photovoltaic power generation and energy storage system in a coal mining subsidence area can provide power to grid-connected loads, while simultaneously storing energy when the grid has sufficient power and providing power to the grid when it needs it. The application of the energy storage system enhances the integrity and flexibility of the photovoltaic power generation system. Furthermore, the system has a simple structure, low cost, and is easy to use.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic power generation technology, and in particular to a photovoltaic power generation and energy storage system for coal mining subsidence areas. Background Technology

[0002] Coal mining subsidence areas are regions where geological structures have changed due to underground coal mining, leading to surface subsidence, cracks, and other deformations. The governance and transformation of these areas has become a core issue for the sustainable development of resource-based cities. Integrating photovoltaic projects with the governance of coal mining subsidence areas represents an innovative model for energy transformation and ecological restoration in my country. This approach can alleviate land scarcity in central and eastern China, improve land utilization efficiency, and achieve a "win-win" situation for both ecological restoration and power generation revenue. Photovoltaic power generation converts light energy into electrical energy by having solar panels absorb photons, generate electron-hole pairs, and form an electric current.

[0003] In existing technologies, when photovoltaic power plants are built in coal mining subsidence areas to transmit electricity to the grid, energy utilization is insufficient during periods of low grid load. However, by constructing energy storage devices to combine solar photovoltaic power generation in coal mining subsidence areas with energy storage technology to store excess energy, grid stability can be improved. Utility Model Content

[0004] The purpose of this utility model is to provide a photovoltaic power generation and energy storage system for coal mining subsidence areas, so as to solve the problem of resource waste in coal mining subsidence areas, make full use of resources in coal mining subsidence areas according to local conditions, and solve the problems of limited application scenarios and incomplete functions of current photovoltaic power generation and energy storage systems in coal mining subsidence areas.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a photovoltaic power generation and energy storage system for coal mining subsidence areas, comprising: a booster unit, an energy storage unit, a control unit, and multiple sets of photovoltaic power generation units; the photovoltaic power generation units are connected to the booster unit, the energy storage units are connected to the booster unit, and the booster unit is connected to the power grid; the control unit is connected to the photovoltaic power generation units and the energy storage units; The photovoltaic power generation unit includes: photovoltaic power generation modules, string inverters, and photovoltaic-side transformer substations. Several sets of photovoltaic power generation modules are connected in series to form photovoltaic strings; multiple sets of photovoltaic strings are connected to the same string inverter; multiple string inverters are connected to the same photovoltaic-side transformer substations; and multiple photovoltaic-side transformer substations are connected to a step-up unit. The boosting unit includes a switching station and a boosting station. Multiple photovoltaic-side transformers are connected to a switching station, and the switching station is connected to the boosting station. Electricity is then fed into the power grid through the boosting station. The energy storage unit includes: an energy storage side transformer and several energy storage subsystems. Each energy storage subsystem includes: an energy storage battery compartment and an energy storage converter. Multiple energy storage battery compartments and one energy storage converter are connected. The energy storage converters in the multiple energy storage subsystems are connected to the energy storage side transformer. The energy storage side transformer is connected to a switchgear. The control unit is communicatively connected to the photovoltaic power generation unit, the boost unit, and the energy storage unit.

[0006] Furthermore, the photovoltaic power generation module is a monocrystalline silicon bifacial photovoltaic power generation module, used to convert solar energy into direct current. Several sets of photovoltaic modules are connected in series at the DC end of a string inverter, which converts the direct current into alternating current.

[0007] Furthermore, the photovoltaic power generation module is installed in the coal mining subsidence area using a fixed bracket and is above the flood level; the photovoltaic power generation module is installed at a fixed tilt angle; the foundation of the fixed bracket is made of high-strength prestressed concrete pipe piles; and the fixed bracket is treated with anti-corrosion measures.

[0008] Furthermore, the string inverter is mounted on the fixed bracket of the photovoltaic array via clamps and steel supports.

[0009] Furthermore, the coal mining subsidence area is divided into multiple photovoltaic power generation unit areas. The photovoltaic side transformer is located in the center of the photovoltaic power generation unit area. The foundation of the photovoltaic side transformer adopts high-strength concrete prestressed pipe piles + steel platform foundation. The platform is higher than the flood level. The switch station, energy storage side transformer, and booster station are located on the land side of the coal mining subsidence area.

[0010] Furthermore, in the energy storage subsystem, the DC terminal of the energy storage converter is connected to the energy storage battery compartment, and the AC terminal of the energy storage converter is connected to the energy storage side transformer; the energy storage converter can convert current in both directions.

[0011] Furthermore, the energy storage battery compartment uses lithium batteries; a gas fire suppression system is installed inside the energy storage battery compartment, with each battery module having its own fire suppression nozzle, based on a single battery cabinet; the gas fire suppression system has both manual and automatic activation modes, and can automatically activate to control fire hazards in the event of a fire.

[0012] Furthermore, the energy storage battery compartment is equipped with an emergency ventilation system to remove any gases that may be generated. It can also be used for ventilation. In the event of a fire, it should be able to automatically cut off the power supply to the ventilation fan.

[0013] Furthermore, the control unit is communicatively connected to the photovoltaic power generation unit, the boost unit, and the energy storage unit to acquire measurement data and status signals of the main equipment, and to summarize, analyze, store, and report the obtained information. It is also responsible for communication with remote dispatch to realize the transmission of data and status quantities and the communication of control commands.

[0014] Compared with existing technologies, the advantages of this invention are as follows: Constructing a photovoltaic power generation and energy storage system in a coal mining subsidence area can provide power to grid-connected loads, store electricity when the grid has sufficient power, and supply power to the grid when it needs it. The application of the energy storage system enhances the integrity and flexibility of the photovoltaic power generation system. Furthermore, the system has a simple structure, low cost, and is easy to use. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model.

[0016] Figure 2 This is another structural schematic diagram of the present utility model.

[0017] Figure 3 This is a schematic diagram showing the location of the photovoltaic-side transformer box of this utility model.

[0018] In the diagram: 1. Photovoltaic power generation unit; 2. Step-up unit; 3. Energy storage unit; 4. Control unit; 5. Power grid; 6. Photovoltaic power generation module; 7. Fixed support; 8. String inverter; 9. Photovoltaic side transformer; 10. Switching station; 11. Step-up substation; 12. Energy storage side transformer; 13. Energy storage converter; 14. Energy storage battery compartment; 15. Emergency ventilation system; 16. Coal mining subsidence area. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] Please see Figure 1 A photovoltaic power generation and energy storage system for coal mining subsidence areas is disclosed. The control unit 4 controls the photovoltaic power generation unit 1, the boost unit 2, and the energy storage unit 3. The control unit 4 controls multiple photovoltaic power generation units 1 to generate electricity, which is then supplied to the power grid 5 via the boost unit 2. The control unit 4 can also control the electricity generated by the photovoltaic power generation units 1 to charge the energy storage unit 3 for energy storage. The control unit 4 charges the energy storage unit 3 during the off-peak period of the power grid 5 and discharges it during the peak period of the power grid 5 for peak regulation. The control unit 4 participates in the dispatching of the power grid 5 as an excellent regulating power source. The control unit 4 is connected to the dispatching system of the power grid 5 and is responsible for the dispatching of the photovoltaic power generation and energy storage system by the dispatching system.

[0021] Please see Figure 2 A photovoltaic power generation and energy storage system for coal mining subsidence areas, wherein, The photovoltaic power generation unit 1 includes: photovoltaic power generation modules 6, string inverters 8, and photovoltaic-side transformer substations 9. Several sets of the photovoltaic power generation modules 6 are connected in series to form photovoltaic strings. The photovoltaic power generation unit 1 has several photovoltaic strings, string inverters 8, and photovoltaic-side transformer substations 9. Multiple sets of photovoltaic strings are connected to the same string inverter 8. Multiple string inverters 8 are connected to the same photovoltaic-side transformer substation 9. Multiple photovoltaic-side transformer substations 9 are connected to the boost unit 2.

[0022] The booster unit 2 includes a switch station 10 and a booster station 11, with multiple photovoltaic-side transformers 9 connected to one switch station 10.

[0023] The control unit 4 is communicatively connected to the photovoltaic power generation unit 1, the boost unit 2, and the energy storage unit 3.

[0024] The photovoltaic power generation module 6 is a monocrystalline silicon bifacial photovoltaic power generation module 6, used to convert solar energy into direct current. Several sets of photovoltaic power generation modules 6 are connected in series to form a photovoltaic string. Several sets of photovoltaic strings are connected to the DC terminal of the string inverter 8, which converts the direct current into alternating current. The photovoltaic power generation modules 6 are installed in the coal mining subsidence area 16 using fixed brackets 7, with the photovoltaic power generation modules 6 being more than 2m above the water surface to avoid the photovoltaic power generation modules 6 being affected by the rising water level. At the same time, under the premise of saving costs and obtaining the best sunlight, this system adopts a fixed tilt angle to install the photovoltaic power generation modules 6. In order to stably install the fixed brackets 7 in the coal mining subsidence area, this utility model uses high-strength concrete prestressed pipe piles as the foundation of the fixed brackets 7 and the fixed brackets 7 are treated with anti-corrosion. The output terminals of multiple sets of string inverters 8 are connected to the input terminals of photovoltaic side transformer substations 9, and the output terminals of multiple sets of photovoltaic side transformer substations 9 are connected to the switchgear 10. The energy storage unit 3 includes: an energy storage side transformer substation 12 and several energy storage subsystems. The switchgear 10 is connected to the energy storage side transformer substation 12, which is connected to multiple energy storage subsystems. Each energy storage subsystem includes an energy storage converter 13 and multiple energy storage battery compartments 14. The DC terminal of the energy storage converter 13 is connected to the energy storage battery compartment 14, and the AC terminal of the energy storage converter 13 is connected to the energy storage side transformer substation 12. The energy storage converter 13 can convert current in both directions to meet the charging and discharging needs of the energy storage unit 3. The batteries in the energy storage battery compartment 14 are lithium batteries. A gas fire extinguishing system is installed in the energy storage battery compartment 14. The gas fire extinguishing system has both manual and automatic start-up modes and can be automatically activated to control fire hazards. An emergency exhaust ventilation system 15 is also installed in the energy storage battery compartment 14 to exhaust any gases that may be generated. It can also be used for ventilation. In the event of a fire, it should be able to automatically cut off the power supply to the ventilation fan.

[0025] The switching station 10 is connected to the booster station 11, and supplies power to the power grid 5 through the booster station 11.

[0026] Please see Figure 3 Photovoltaic power generation unit 1 and photovoltaic side transformer 9 are located in coal mining subsidence area 16. Photovoltaic side transformer 9 is arranged in the center of the photovoltaic power generation unit 1 area, which is convenient for maintenance and saves on cables. In the description of this utility model, it should be understood that the terms "center", "upper", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0027] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0028] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A coal mining subsidence area photovoltaic power generation and energy storage system, characterized in that, include: A boost unit (2), an energy storage unit (3), a control unit (4), and a photovoltaic power generation unit (1); multiple sets of the photovoltaic power generation units (1) are connected to the boost unit (2), the energy storage unit (3) is connected to the boost unit (2), and the boost unit (2) is connected to the power grid (5); the control unit (4) is connected to the photovoltaic power generation unit (1) and the energy storage unit (3); The photovoltaic power generation unit (1) includes: photovoltaic power generation modules (6), string inverters (8), and photovoltaic side transformers (9). Several sets of photovoltaic power generation modules (6) are connected in series to form photovoltaic strings; multiple sets of photovoltaic strings are connected to the same string inverter (8); multiple string inverters (8) are connected to the same photovoltaic side transformers (9); and multiple photovoltaic side transformers (9) are connected to the boost unit (2). The boosting unit (2) includes a switch station (10) and a boosting station (11). Multiple photovoltaic-side transformers (9) are connected to a switch station (10). The switch station (10) is connected to the boosting station (11), and the power is sent to the power grid (5) through the boosting station (11). The energy storage unit (3) includes: an energy storage side transformer (12) and several energy storage subsystems. The energy storage subsystems include: an energy storage battery compartment (14) and an energy storage converter (13). Multiple energy storage battery compartments (14) and one energy storage converter (13) are connected. The energy storage converters (13) in the several energy storage subsystems are connected to the energy storage side transformer (12). The energy storage side transformer (12) is connected to the switchgear (10). The control unit (4) is communicatively connected to the photovoltaic power generation unit (1), the boost unit (2), and the energy storage unit (3).

2. The coal mining subsidence area photovoltaic power generation and energy storage system according to claim 1, characterized in that, The photovoltaic power generation module (6) is a monocrystalline silicon bifacial photovoltaic power generation module (6), which is used to convert solar energy into direct current. Several sets of photovoltaic modules are connected to the DC end of the string inverter (8), and the string inverter converts the direct current into alternating current.

3. The coal mining subsidence area photovoltaic power generation and energy storage system according to claim 1, characterized in that, The photovoltaic power generation module (6) is installed in the coal mining subsidence area (16) using a fixed bracket (7) and the photovoltaic power generation module (6) is higher than the historical highest flood level; the photovoltaic power generation module (6) is installed at a fixed tilt angle; the foundation of the fixed bracket (7) is made of high-strength concrete prestressed pipe piles; the fixed bracket (7) is treated with anti-corrosion.

4. The coal mining subsidence area photovoltaic power generation and energy storage system according to claim 3, characterized in that, The string inverter is mounted on the photovoltaic array fixed bracket (7) by means of clamps and steel brackets.

5. The coal mining subsidence area photovoltaic power generation and energy storage system according to claim 1, characterized in that, In the coal mining subsidence area (16), multiple photovoltaic power generation units (1) are divided into areas. The photovoltaic side transformer (9) is located in the center of the photovoltaic power generation unit (1) area. The foundation of the photovoltaic side transformer (9) adopts high-strength concrete prestressed pipe piles + steel platform foundation. The platform is higher than the highest historical flood level. The switch station (10), energy storage side transformer (12), and booster station (11) are located on the land side of the coal mining subsidence area (16).

6. The coal mining subsidence area photovoltaic power generation and energy storage system according to claim 1, characterized in that, The DC end of the energy storage converter (13) in the energy storage subsystem is connected to the energy storage battery compartment (14), and the AC end of the energy storage converter (13) is connected to the energy storage side transformer (12); the energy storage converter (13) can convert power bidirectionally as needed.

7. The coal mining subsidence area photovoltaic power generation and energy storage system according to claim 6, characterized in that, The battery in the energy storage battery compartment (14) is a lithium battery; a gas fire extinguishing system is installed in the energy storage battery compartment (14); the gas fire extinguishing system has two start-up modes, manual and automatic, and can be automatically started to control the fire hazard once there is a fire hazard.

8. The coal mining subsidence area photovoltaic power generation and energy storage system according to claim 6, characterized in that, An emergency ventilation system (15) is installed inside the energy storage battery compartment (14) to remove any gases that may be generated. It can also be used for ventilation. In the event of a fire, it should be able to automatically cut off the power supply to the ventilation fan.

9. The coal mining subsidence area photovoltaic power generation and energy storage system according to claim 1, characterized in that, The control unit (4) is connected to the photovoltaic power generation unit (1), the boost unit (2) and the energy storage unit (3) to obtain the measurement data and status signals of the main equipment, and to summarize, analyze, store and report the obtained information. It is also responsible for communication with the remote dispatcher to realize the transmission of data and status quantities and the transmission of control commands.

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