A photovoltaic energy storage microgrid power generation device

Abstract

This utility model relates to the field of power supply technology, specifically to a photovoltaic-storage microgrid power generation device, including photovoltaic modules, an energy storage cabinet, a grid-connected cabinet, and an EMS energy management system. The DC power output terminal of the photovoltaic modules is connected to the DC power input terminal of the energy storage cabinet to convert solar energy into DC power. The grid-connected cabinet includes an energy storage grid-connected cabinet and a mains grid-connected cabinet. The energy storage grid-connected cabinet is equipped with a first electricity meter, a first smart circuit breaker, and a second smart circuit breaker. The energy storage grid-connected cabinet also includes a second electricity meter, a reverse current protection device, a third smart circuit breaker, an anti-islanding protection device, an uninterruptible power supply (UPS), and a single-phase switch. The EMS energy management system is the core control unit of the photovoltaic-storage microgrid power generation device, responsible for monitoring, controlling, and managing the entire device. This utility model solves the problem in existing technologies where grid outages during extreme weather in remote areas result in users being unable to use electricity normally.

Description

Technical Field

[0001] This utility model relates to the field of power supply technology, and more specifically, to a photovoltaic-storage microgrid power generation device. Background Technology

[0002] As a core infrastructure of modern society, the power supply system has undergone leapfrog development, evolving from direct current (DC) to alternating current (AC), from single energy sources to multi-energy complementarity, and from manual operation to intelligent control. Power supply devices convert various energy sources (such as coal, hydropower, wind power, and solar energy) into electrical energy, and through transmission, transformation, and distribution, safely, reliably, and economically deliver this energy to various end users. The power supply system consists of power plants, transmission networks, substations, distribution networks, and electrical equipment, and is an indispensable infrastructure of modern society. As the core energy support for industrial production, transportation, communication networks, and residential life, the power supply system is directly related to national economic development, social stability, and people's living standards.

[0003] In existing microgrid energy storage and generation devices, the microgrid energy storage and generation devices are mainly used to provide auxiliary power to the main grid, operating when the main grid's power is insufficient to ensure the stable operation of the load. Existing microgrid systems cannot flexibly determine whether the microgrid energy storage and generation devices operate off-grid or on-grid based on the main grid's power outage and operation states. Furthermore, among existing mainstream microgrid energy storage and generation devices, few support off-grid operation, making them unsuitable for extreme weather, harsh climates, and remote, uncommon terrain.

[0004] However, extreme weather events, such as blizzards, strong winds, torrential rains, and droughts, are frequently encountered during power supply. In some remote, high-altitude, and climate-sensitive areas, natural disasters such as wildfires are prone to occur. When these situations arise, the power company will implement power outage measures to prevent transmission system failures caused by extreme weather or natural disasters, which could result in greater personal and economic losses. However, these measures will impact the user experience and daily life of consumers, causing significant inconvenience to residents in these areas. Summary of the Invention

[0005] The purpose of this application is to provide a photovoltaic-storage microgrid power generation device, which solves the problem in the prior art that the user end cannot use electricity normally when the main grid fails to avoid disaster during extreme weather in remote areas.

[0006] To solve the above-mentioned technical problems, the solution adopted in this application is as follows: A photovoltaic-storage microgrid power generation device includes photovoltaic modules and an energy storage cabinet; The photovoltaic module (1) is used to convert solar energy into DC power, and the DC power output terminal of the photovoltaic module (1) is connected to the DC power input terminal of the energy storage cabinet (2). The energy storage cabinet (2) includes an inverter (22) and an energy storage battery (21). The DC power output terminal of the photovoltaic module (1) is connected to the DC power input terminal of the energy storage battery (21) via a cable; at the same time, the DC power output terminal of the photovoltaic module (1) is connected to the DC power input terminal of the inverter (22) via a cable. The photovoltaic-storage microgrid power generation device also includes a grid-connected cabinet; the grid-connected cabinet includes an energy storage grid-connected cabinet (3) and a mains grid-connected cabinet (4); the energy storage grid-connected cabinet (3) is equipped with a first electricity meter (31), a first smart circuit breaker (32), and a second smart circuit breaker (33); the AC power output terminal of the inverter (22) is connected to the first smart circuit breaker (32) and the second smart circuit breaker (33) through two independent cables, and the other end of the first smart circuit breaker (32) and the second smart circuit breaker (33) is connected to the first electricity meter (31); The mains power grid-connected cabinet (4) is equipped with a second electricity meter (41), an anti-reverse current device (42), a third intelligent circuit breaker (43), and an anti-islanding protection device (44). The power output terminal of the mains power grid-connected cabinet (4) is connected to the power input terminal of the load (5) to supply power to the load (5). One end of the second electricity meter (41) is connected to the main grid (6) power input terminal, and the other end is connected to the anti-reverse current device (42). The other end of the anti-reverse current device (42) is connected to the third intelligent circuit breaker (43), thereby realizing the access of the main grid (6) power. One end of the third intelligent circuit breaker (43) is connected to the anti-islanding protection device (44). The energy storage grid-connected cabinet (3) is equipped with an uninterruptible power supply (UPS) (35) and a single-phase switch (34); one end of the uninterruptible power supply (UPS) (35) is connected to the single-phase switch (34), and the other end of the single-phase switch (34) is connected to the first intelligent circuit breaker (32) and the second intelligent circuit breaker (33). The energy storage battery (21) can charge the uninterruptible power supply (UPS) (35); the other end of the uninterruptible power supply (UPS) (35) is connected to the first electricity meter (31), the second electricity meter (41), the anti-reverse current device (42), the third intelligent circuit breaker (43), and the anti-islanding protection device (44) respectively.

[0007] Preferably, the photovoltaic-storage microgrid power generation device includes an EMS energy management system (7); the EMS energy management system (7) is connected to a second electricity meter (41), an anti-reverse current device (42), a third intelligent circuit breaker (43), and an anti-islanding protection device (44) via an RS485 bus.

[0008] Preferably, the photovoltaic module (1) is a 620Wp photovoltaic module.

[0009] Preferably, the uninterruptible power supply (UPS) (35) has a capacity of 2kVA; the single-phase switch (34) has a specification of 2P25A.

[0010] The technical solution of this application has at least the following advantages and beneficial effects: 1. This utility model includes an energy storage battery, photovoltaic modules, and an inverter. The energy storage battery is connected to the output end of the photovoltaic modules and simultaneously to the power input end of the inverter, ensuring smooth power transmission between the components. This utility model's photovoltaic-energy storage microgrid power generation device stores excess energy through the energy storage battery and releases it at night or when sunlight is insufficient. The energy storage battery supplies power to the user end, ensuring a stable power supply. In the event of a main grid outage, the energy storage battery and photovoltaic modules can simultaneously supply power to the user end, ensuring normal power consumption. This solves the problem of users being unable to use power normally due to main grid outages during extreme weather in remote areas, providing users with comprehensive and reliable power protection. Furthermore, this device can be used in remote areas, high-altitude areas, and areas with abundant or insufficient sunlight resources, exhibiting wide applicability and flexibility.

[0011] 2. This utility model is equipped with an inverter, which can convert the DC power of the photovoltaic module into AC power for the load. It can also invert the DC power of the energy storage battery and output it at night or when there is insufficient sunlight, so as to realize the efficient utilization of electrical energy.

[0012] 3. This utility model is equipped with an EMS energy management device, which can monitor the operating status and parameters of the main grid, photovoltaic modules, energy storage cabinet, and grid-connected cabinet in real time to ensure the stable operation of the system.

[0013] 4. This utility model is equipped with an anti-reverse current device to protect the main grid circuit and prevent current from flowing from the energy storage battery and photovoltaic modules to the main grid circuit. In addition, this device is equipped with an anti-islanding protection device to prevent the formation of an islanding effect, so that the energy storage battery and photovoltaic modules can continue to supply power to the load when the main grid is powered off. Attached Figure Description

[0014] Fig. 1 This is a structural topology diagram of the present invention; Fig. 2 This is a diagram showing the electrical connection relationships of the equipment in this utility model.

[0015] In the diagram: 1-Photovoltaic module, 2-Energy storage cabinet, 21-Energy storage battery, 22-Inverter, 3-Energy storage grid-connected cabinet, 31-First electricity meter, 32-First smart circuit breaker, 33-Second smart circuit breaker, 34-Single-phase switch, 35-Uninterruptible power supply (UPS), 36-Incoming switch at the front end of the energy storage cabinet, 4-Main grid-connected cabinet, 41-Second electricity meter, 42-Anti-backflow device, 43-Third smart circuit breaker, 44-Anti-islanding protection device, 45-Load back-end transmission line, 5-Load, 6-Main grid, 7-EMS energy management system. Detailed Implementation

[0016] 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.

[0017] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. The terms "center," "upper," "lower," "inner," and "outer," indicating orientation or positional relationships based on the orientation or positional relationships shown in the figures, or the orientation or positional relationships commonly used when the product is in use, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operated in a specific orientation, and therefore should not be construed as a limitation on this application. It should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0018] Please refer to Figs. 1-2 This utility model provides a photovoltaic-storage microgrid power generation device, including photovoltaic modules, energy storage cabinet, grid-connected cabinet, and EMS energy management system.

[0019] Furthermore, photovoltaic module 1 is used to convert solar energy into direct current (DC) electricity, providing renewable energy input for the device. The photovoltaic module is installed outdoors, facing the sun.

[0020] In this invention, 35 photovoltaic modules of 620Wp each are used.

[0021] Furthermore, the energy storage cabinet 2 includes an inverter 22 and an energy storage battery 21.

[0022] Specifically, the DC power output terminal of photovoltaic module 1 is connected to the DC power input terminal of the energy storage battery through H1Z2Z2-1*4 cable; at the same time, the DC power output terminal of photovoltaic module 1 is connected to the DC power input terminal of inverter 22 through H1Z2Z2-1*4 cable.

[0023] Specifically, the energy storage battery 21 is used to store electrical energy. When the power generation exceeds the power demand, it stores excess electrical energy and releases electrical energy when the power generation is insufficient or there is a power outage, thus ensuring a stable power supply.

[0024] Specifically, the inverter 22 is used to convert the DC power input from the photovoltaic module into AC power, and can also be used in conjunction with the energy storage battery 21 to realize the grid-connected output and off-grid output of the energy stored in the energy storage battery.

[0025] It should be noted that the grid-connected output is supplied to the user end by photovoltaic module 1, energy storage battery 21, and the main grid 6. The off-grid output is supplied to the user end when the main grid 6 is disconnected from power. Specifically, photovoltaic module 1 does not output power at night or when sunlight is insufficient. The main grid 6 is supplied with mains electricity.

[0026] More specifically, at night or when there is insufficient sunlight, the inverter 22 can convert the DC power stored in the energy storage battery 21 into AC power and output it to power the load; when there is sufficient sunlight, the inverter 22 can convert the DC power output by the photovoltaic module 1 into AC power and transmit it to the load 5 through the subsequent circuit to power the user.

[0027] In this invention, the energy storage battery is a 280Ah lithium iron phosphate battery.

[0028] Furthermore, the grid-connected cabinet includes an energy storage grid-connected cabinet 3 and a mains grid-connected cabinet 4. The energy storage grid-connected cabinet 3 is equipped with a first electricity meter 31, a first intelligent circuit breaker 32, and a second intelligent circuit breaker 33. The first electricity meter 31 is used to measure the amount of electrical energy used in the energy storage circuit during a specific time period. The first intelligent circuit breaker 32 and the second intelligent circuit breaker 33 have opening and closing control and intelligent monitoring functions, used to control the on / off of the circuit, realizing grid-connected and off-grid output of the energy storage.

[0029] Specifically, when the main grid 6 is de-energized, the smart circuit breaker 33 closes, and the energy storage end (photovoltaic module 1, energy storage battery 21) is off-grid output; when the main grid 6 is operating normally, the smart circuit breaker 32 closes, and the energy storage end (photovoltaic module 1, energy storage battery 21) is connected to the grid for output.

[0030] Specifically, the energy storage grid-connected cabinet 3 is also equipped with an uninterruptible power supply UPS 35, hereinafter referred to as UPS.

[0031] Specifically, one end of the UPS is connected to a single-phase switch 34, and the other end of the single-phase switch 34 is connected to the first intelligent circuit breaker 32 and the second intelligent circuit breaker 33. The energy storage battery 21 can charge the UPS. The other end of the UPS is connected to the first electricity meter 31, the second electricity meter 21, the anti-reverse current device 42, the third intelligent circuit breaker 43, and the anti-islanding protection device 44.

[0032] Specifically, when the main grid 6 experiences a power outage, the second intelligent circuit breaker 33 closes, allowing the photovoltaic module 1 and energy storage battery 21 to output power off-grid, while simultaneously charging the UPS through single-phase switch 34. When the main grid 6 is operating normally, the first intelligent circuit breaker 32 closes, allowing the photovoltaic module 1 and energy storage battery 21 to output power back to the grid, while simultaneously charging the UPS through single-phase switch 34. Thus, when the main grid 6 experiences a power outage, the UPS can act as an emergency power source to supply power to load 5.

[0033] It should be noted that the uninterruptible power supply (UPS) has a capacity of 2kVA.

[0034] It should be noted that the specifications for a single-phase switch are 2P 25A.

[0035] Specifically, the AC power output terminal of inverter 22 is connected to the first intelligent circuit breaker 32 and the second intelligent circuit breaker 33 through two independent ZC-YJV22-0.6 / 1KV-4*35+1*25 cables. The other end of the first intelligent circuit breaker 32 and the second intelligent circuit breaker 33 is connected to the first electricity meter 31.

[0036] Specifically, the grid-connected cabinet 4 is equipped with a second electricity meter 41, an anti-reverse current device 42, a third intelligent circuit breaker 43, and an anti-islanding protection device 44. The second electricity meter 41 is used to measure the amount of electrical energy used in the mains circuit during a specific period. The third intelligent circuit breaker 43 has the functions of opening and closing control and intelligent monitoring, and is used to control the connection and disconnection of the main grid circuit 6. The anti-reverse current device 42 is used to protect the main grid circuit 6, which is the mains circuit, and to prevent current from flowing back from the energy storage battery 21 and the photovoltaic module 1 to the main grid circuit. The anti-islanding protection device 44 is used to prevent the formation of an islanding effect, so that when the main grid 6 is de-energized, the energy storage battery 21 and the photovoltaic module 1 can continue to supply power to the load 5.

[0037] It should be noted that in this utility model, the first intelligent circuit breaker 32, the second intelligent circuit breaker 33, and the third intelligent circuit breaker 43 are all 4P 100A.

[0038] Specifically, the grid-connected mains cabinet 4 is used to control the main grid 6 and the energy storage terminal (photovoltaic module 1, energy storage battery 21) of the photovoltaic-storage microgrid power generation device to jointly supply power to the load 5. The power output terminal of the grid-connected mains cabinet 4 is connected to the power input terminal of the load 5 to supply power to the load 5.

[0039] Specifically, the power output terminal of the main grid 6 is connected to one end of the second electricity meter 41 via a cable. The other end of the second electricity meter 41 is connected to the anti-backflow device 42, and the other end of the anti-backflow device 42 is connected to the third intelligent circuit breaker 43, thereby realizing the access of the main grid power. One end of the third intelligent circuit breaker 43 is connected to the anti-islanding protection device 44.

[0040] Specifically, when the main grid 6 is operating normally, the main grid 6 power is connected to the load back-end transmission line 45 by closing the smart circuit breaker 43. At the same time, the front-end incoming switch 36 of the energy storage grid-connected cabinet 3 is closed, connecting the power of the energy storage end of the photovoltaic-storage microgrid power generation device (photovoltaic module 1 and energy storage battery 21) to the load back-end transmission line 45, and jointly outputting power to the load 5 to supply it. When the main grid 6 is de-energized, the smart circuit breaker 43 is opened. At this time, only the power of the energy storage end of the photovoltaic-storage microgrid power generation device (photovoltaic module 1 and energy storage battery 21) is connected to the load back-end transmission line 45 to supply power to the load 5 alone.

[0041] Furthermore, this photovoltaic-storage microgrid power generation device is equipped with an EMS energy management system 7. The EMS energy management system is located inside the energy storage cabinet 2 and is connected to the data transmission interfaces of multiple devices via an RS485 bus. The first electricity meter 31 and the energy storage cabinet 2 transmit data via an RS485 connection. In addition, the EMS energy management system 7 is connected to the second electricity meter 41, the anti-reverse current device 42, the third intelligent circuit breaker 43, and the anti-islanding protection device 44 via an RS485 bus, forming a communication network to collect real-time data such as the operating status and parameters of each device.

[0042] Specifically, the EMS (Energy Management System 7) is the core control unit of the photovoltaic-storage microgrid power generation device, responsible for monitoring, controlling, and managing the entire device. The EMS system collects real-time operating data, fault and protection data from the photovoltaic-storage microgrid power generation device. Real-time operating data includes voltage, current, active power, reactive power, power generation, grid connection status, switch status, energy storage system charging and discharging power, state of charge, temperature, inverter operating mode, and switch status. Fault and protection data includes overcurrent / overvoltage / undervoltage alarms, communication interruption records, and other faults.

[0043] Example 1 This utility model was deployed at a proposed photovoltaic site near Moska Village, Danba County, Ganzi Prefecture. The device mainly consists of a grid-connected cabinet, an energy storage cabinet, photovoltaic modules, and an EMS energy management system. The photovoltaic modules are 162 Tongwei brand 620Wp modules, installed at a 40° south-facing angle; two 50kW inverters are configured; and two 125kW / 261kWh energy storage batteries are used, equipped with liquid cooling and waterproofing.

[0044] Normal operating conditions: When the main grid is supplying power normally, the EMS energy management system monitors the operating status and parameters of the main grid, photovoltaic modules, energy storage cabinets, and grid-connected cabinets in real time. The main grid supplies power to users and energy storage batteries. At the same time, the photovoltaic modules convert solar energy into electrical energy. After conversion by the inverter, a portion is supplied to users, and the remaining electrical energy charges the energy storage batteries, completing the energy storage.

[0045] Main grid outage mode: When the main grid experiences a power outage, the photovoltaic-storage microgrid power generation device operates off-grid, with the photovoltaic modules and energy storage batteries supplying power to users. Specifically, during the day, the photovoltaic modules and energy storage batteries work together to supply power to users; at night, the photovoltaic modules stop generating electricity, and the energy storage batteries alone undertake the power supply task. However, the energy storage batteries will not be charged and discharged simultaneously to ensure stable operation and lifespan of the device.

[0046] This embodiment demonstrates the application of a photovoltaic-storage microgrid power generation device in high-altitude, complex terrain areas to cope with grid outages and mitigate risks.

[0047] It should be noted that all the electronic devices mentioned in the above embodiments are available in domestic and international markets.

[0048] The various embodiments of this utility model have now been described in detail. To avoid obscuring the concept of this utility model, some details known in the art have not been described. Those skilled in the art will fully understand how to implement the technical solution of this utility model based on the above description. The scope of this utility model is defined by the appended claims.

Claims

1. A microgrid power generation device, characterized by comprising: Including photovoltaic modules and energy storage cabinets; The photovoltaic module (1) is used to convert solar energy into DC power, and the DC power output terminal of the photovoltaic module (1) is connected to the DC power input terminal of the energy storage cabinet (2). The energy storage cabinet (2) includes an inverter (22) and an energy storage battery (21). The DC power output terminal of the photovoltaic module (1) is connected to the DC power input terminal of the energy storage battery (21) via a cable; at the same time, the DC power output terminal of the photovoltaic module (1) is connected to the DC power input terminal of the inverter (22) via a cable. The photovoltaic-storage microgrid power generation device also includes a grid-connected cabinet; the grid-connected cabinet includes an energy storage grid-connected cabinet (3) and a mains grid-connected cabinet (4); the energy storage grid-connected cabinet (3) is equipped with a first electricity meter (31), a first smart circuit breaker (32), and a second smart circuit breaker (33); the AC power output terminal of the inverter (22) is connected to the first smart circuit breaker (32) and the second smart circuit breaker (33) through two independent cables, and the other end of the first smart circuit breaker (32) and the second smart circuit breaker (33) is connected to the first electricity meter (31); The mains power grid-connected cabinet (4) is equipped with a second electricity meter (41), an anti-reverse current device (42), a third intelligent circuit breaker (43), and an anti-islanding protection device (44). The power output terminal of the mains power grid-connected cabinet (4) is connected to the power input terminal of the load (5) to supply power to the load (5). One end of the second electricity meter (41) is connected to the main grid (6) power input terminal, and the other end is connected to the anti-reverse current device (42). The other end of the anti-reverse current device (42) is connected to the third intelligent circuit breaker (43), thereby realizing the access of the main grid (6) power. One end of the third intelligent circuit breaker (43) is connected to the anti-islanding protection device (44). The energy storage grid-connected cabinet (3) is equipped with an uninterruptible power supply (UPS) (35) and a single-phase switch (34); one end of the uninterruptible power supply (UPS) (35) is connected to the single-phase switch (34), and the other end of the single-phase switch (34) is connected to the first intelligent circuit breaker (32) and the second intelligent circuit breaker (33). The energy storage battery (21) can charge the uninterruptible power supply (UPS) (35); the other end of the uninterruptible power supply (UPS) (35) is connected to the first electricity meter (31), the second electricity meter (41), the anti-reverse current device (42), the third intelligent circuit breaker (43), and the anti-islanding protection device (44) respectively.

2. The optical storage micro-grid power generation device according to claim 1, characterized in that, The photovoltaic-storage microgrid power generation device includes an EMS energy management system (7); the EMS energy management system (7) is connected to a second electricity meter (41), an anti-reverse current device (42), a third intelligent circuit breaker (43), and an anti-islanding protection device (44) via an RS485 bus.

3. The optical storage micro-grid power generation device according to claim 2, characterized in that, The photovoltaic module (1) is a 620Wp photovoltaic module.

4. The optical storage micro-grid power generation device according to claim 3, characterized in that, The uninterruptible power supply (UPS) (35) has a capacity of 2kVA; the single-phase switch (34) has a specification of 2P 25A.

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