Energy management device of light-storage direct-flexible micro-grid

Abstract

The utility model discloses an energy management device of an optical storage direct flexible micro-grid. The energy management device comprises a data acquisition module, a data storage module and a strategy control module, the strategy control module is connected with the switch. One end of the first switch is connected with the AC bus, and the other end of the first switch is connected with the distribution line; one end of the second switch is connected with the AC load, and the other end of the second switch is connected with the AC bus; one end of the third switch is connected with the direct-current bus, and the other end of the third switch is connected with the alternating-current bus; one end of the fourth switch is connected with the V2G charging pile, and the other end of the fourth switch is connected with the direct current bus; one end of the fifth switch is connected with the direct-current load, and the other end of the fifth switch is connected with the direct-current bus; one end of the sixth switch is connected with the energy storage battery device, and the other end of the sixth switch is connected with the direct current bus; one end of the seventh switch is connected with the photovoltaic power generation device, and the other end of the seventh switch is connected with the direct current bus. The device can realize multi-energy complementation and supply-demand matching, and improves the reliability and economy of the micro-grid.

Description

Technical Field

[0001] This utility model relates to the field of control technology for photovoltaic-storage-DC-flexible microgrids, specifically to an energy management device for photovoltaic-storage-DC-flexible microgrids. Background Technology

[0002] Under the global trend of clean energy transition, photovoltaic-storage-DC-flexible microgrids integrate photovoltaic, energy storage, DC power distribution, and flexible control technologies to achieve localized power self-sufficiency and flexible dispatch, effectively improving the utilization efficiency of renewable energy and reducing grid dependence. However, current system energy management has significant problems: photovoltaic output fluctuates greatly due to weather conditions, and energy storage equipment has limited charging and discharging efficiency and lifespan, making it difficult to dynamically balance power generation, energy storage, and power consumption, resulting in energy waste and increased battery wear.

[0003] Existing energy management devices employ simplistic control strategies and lack global optimization capabilities across multiple energy flows, hindering flexible scheduling based on load and equipment status. Furthermore, they suffer from technical bottlenecks in DC voltage stability control, multi-energy storage coordination, and grid interaction response, making it difficult to meet the demands for intelligent and economical operation. Therefore, developing energy management devices with efficient scheduling, precise control, and intelligent coordination is crucial for improving microgrid performance and promoting distributed energy applications. Summary of the Invention

[0004] To address the aforementioned technical issues, this invention proposes an energy management device for a photovoltaic-storage-DC-flexible microgrid. This device enables flexible energy allocation through intelligent control of switches and mode adjustment of converters, adapting to various operating conditions such as grid-connected / islanded operation, load variations, and fluctuations in renewable energy output. This achieves multi-energy complementarity and supply-demand matching, improving the reliability and economy of the microgrid.

[0005] The technical solution adopted by this utility model is as follows:

[0006] An energy management device for a photovoltaic-storage-DC-flexible microgrid, the device comprising:

[0007] Data acquisition module, data storage module, strategy control module;

[0008] The data acquisition module is connected to the data storage module, the data storage module is connected to the strategy control module, and the strategy control module is connected to the first switch K1, the second switch K2, the third switch K3, the fourth switch K4, the fifth switch K5, the sixth switch K6, and the seventh switch K7 respectively.

[0009] One end of the first switch K1 is connected to the AC bus, and the other end of the first switch K1 is connected to the power distribution line.

[0010] One end of the second switch K2 is connected to the AC load, and the other end of the second switch K2 is connected to the AC bus.

[0011] One end of the third switch K3 is connected to the DC bus, and the other end of the third switch K3 is connected to the AC bus.

[0012] One end of the fourth switch K4 is connected to the V2G charging pile, and the other end of the fourth switch K4 is connected to the DC bus.

[0013] One end of the fifth switch K5 is connected to the DC load, and the other end of the fifth switch K5 is connected to the DC bus.

[0014] One end of the sixth switch K6 is connected to the energy storage battery device, and the other end of the sixth switch K6 is connected to the DC bus.

[0015] One end of the seventh switch K7 is connected to the photovoltaic power generation device, and the other end of the seventh switch K7 is connected to the DC bus.

[0016] The data acquisition module includes a sensor, a signal conditioning module, a data acquisition unit, and a communication interface. The sensor is connected to the signal conditioning module, the signal conditioning module is connected to the data acquisition unit, and the data acquisition unit is connected to the data storage module and the communication interface.

[0017] like Figure 1 As shown, the power distribution network is connected to the other end of the first switch K1 through the power distribution line, and one end of the first switch K1 is connected to the AC bus.

[0018] The AC bus is connected to the other end of the third switch K3 via a DC / AC bidirectional rectifier, and one end of the third switch K3 is connected to the DC bus.

[0019] The DC bus is connected to the other end of the fifth switch K5 via a step-down DC / DC converter, and one end of the fifth switch K5 is connected to the DC load.

[0020] The DC bus is connected to the other end of the sixth switch K6 via an energy storage DC / DC converter, and one end of the sixth switch K6 is connected to the energy storage battery device.

[0021] The DC bus is connected to the other end of the seventh switch K7 via a photovoltaic DC / DC converter, and one end of the seventh switch K7 is connected to a photovoltaic power generation device.

[0022] The aforementioned DC / AC bidirectional rectifier has both rectification and inversion functions. During rectification, it converts AC power to DC power; during inversion, it converts DC power back to AC power. It enables bidirectional energy flow between the AC bus and the DC bus, and is used for energy conversion between the distribution network and the DC system.

[0023] The buck DC / DC converter is mainly used to reduce the DC voltage, converting a higher DC voltage into a lower DC voltage suitable for the operation of the DC load, thus playing a role in voltage matching and regulation, and ensuring that the DC load can operate stably under a suitable voltage.

[0024] The energy storage DC / DC converter is used to control the energy exchange between the energy storage battery device and the DC bus. During charging, the electrical energy from the DC bus is charged into the energy storage battery device with appropriate voltage and current parameters; during discharging, the electrical energy from the energy storage battery device is converted into an output form suitable for the DC bus, thereby realizing the charging and discharging control of the energy storage battery device.

[0025] The photovoltaic DC / DC converter processes the DC power output from the photovoltaic power generation device. By adjusting parameters such as voltage and current, it achieves maximum power point tracking of the photovoltaic cells, improves the conversion efficiency and utilization rate of photovoltaic power, and adapts the photovoltaic power to the voltage level of the DC bus.

[0026] In the aforementioned V2G charging pile, V2G is a bidirectional energy transfer technology between electric vehicles and the power grid, enabling both "vehicle-to-grid charging" (the grid supplies power to the vehicle, similar to conventional charging) and "vehicle-to-grid discharging" (the vehicle feeds back energy to the grid, supporting peak shaving and emergency power supply). Its core is the bidirectional conversion of electrical energy through power electronic conversion devices (such as bidirectional AC-DC converters and bidirectional DC-DC converters). These devices are power electronic components or circuits. During charging, the AC power from the grid is rectified into DC power to charge the vehicle battery (rectification mode); during discharging, the DC power from the vehicle battery is inverted back into AC power to feed back to the grid (inverter mode).

[0027] The photovoltaic power generation device includes photovoltaic panels and a centralized photovoltaic inverter, with multiple photovoltaic panels connected to the centralized photovoltaic inverter.

[0028] The energy storage battery device includes an energy storage battery and an energy storage inverter, with the energy storage battery connected to the energy storage inverter.

[0029] This utility model discloses an energy management device for a photovoltaic-storage-DC-flexible microgrid, with the following technical advantages:

[0030] 1) The voltage and power of each component can be monitored in real time through the data acquisition module. Then, based on this data, the energy management device controls the opening and closing of each switch according to a preset strategy to achieve optimal energy management.

[0031] 2) The device has an island operation mode, an autonomous consumption mode, and a peak shaving and valley filling mode, which can improve the self-consumption rate of photovoltaic power generation and the management level of photovoltaic-storage microgrid.

[0032] 3) The device has a simple and practical structure, is easy to install, and can solve the power reliability problem for users in a small area without the need for large-scale upgrades to the existing grid structure, thus saving investment.

[0033] 4) This utility model energy management device, through comprehensive regulation of photovoltaic power generation devices, energy storage battery devices, DC loads, AC loads, and V2G charging piles, can dynamically adjust the working modes of equipment such as V2G charging piles, energy storage systems, and photovoltaic power generation devices according to factors such as grid peak and valley electricity prices, new energy power generation, and load demand, so as to achieve functions such as peak shaving and valley filling and energy cost optimization. It has the characteristics of high intelligence and automation. Attached Figure Description

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0035] Figure 1 This is a schematic diagram of the connection of the photovoltaic-storage-DC-flexible microgrid system of this utility model.

[0036] Figure 2 This is a schematic diagram of the energy management device for a photovoltaic-storage-DC-flexible microgrid system according to this utility model.

[0037] Figure 3 This is a schematic diagram of the photovoltaic power generation device of this utility model.

[0038] Figure 4 This is a schematic diagram of the energy storage battery device of this utility model.

[0039] Figure 5 This is a schematic diagram of the data acquisition module of this utility model.

[0040] Wherein: K1: First switch; K2: Second switch; K3: Third switch; K4: Fourth switch; K5: Fifth switch; K6: Sixth switch; K7: Seventh switch; 8: Distribution network; 9: Distribution line; 10: AC bus; 11: AC load; 12: DC / AC bidirectional rectifier; 13: DC bus; 14: V2G charging pile; 15: Step-down DC / DC converter; 16: DC load; 17: Energy storage DC / DC converter; 18: Energy storage battery device; 19: Photovoltaic DC / DC converter; 20: Photovoltaic power generation device; 21: Data acquisition module; 22: Data storage module; 23: Strategy control module; 24: Photovoltaic panel; 25: Photovoltaic centralized inverter; 26: Energy storage battery; 27: Energy storage battery inverter; 28: Sensor; 29: Signal conditioning module; 30: Data acquisition module; 31: Communication interface. Detailed Implementation

[0041] like Figure 2 As shown, this utility model embodiment provides an energy management device for a photovoltaic-storage-DC-flexible microgrid system:

[0042] In this invention, the photovoltaic-storage DC-flexible microgrid energy management device collects the electricity consumption information of DC load 16, AC load 11 and V2G charging pile 14 and the operation information of the grid connection point of photovoltaic power generation device 20. After analysis by the strategy control module 23, it outputs control signals to control the operation mode of photovoltaic power generation device 20 and energy storage battery device 18, thereby improving the self-consumption rate of photovoltaic power generation.

[0043] The data acquisition module 21 is connected to the data storage module 22; the storage module 22 is connected to the strategy control module 23; the strategy control module 23 is connected to the first switch K1, the second switch K2, the third switch K3, the fourth switch K4, the fifth switch K5, the sixth switch K6, and the seventh switch K7 respectively.

[0044] One end of the first switch K1 is connected to the AC bus 10, and the other end is connected to the A-phase, B-phase, and C-phase lines of the 380V power distribution line.

[0045] The second switch K2 is connected at one end to the AC load 11 and at the other end to the A, B, and C phases of the 380V power distribution line.

[0046] The third switch K3 is connected to the DC bus 13 at one end and to the A, B and C phases of the 380V power distribution line at the other end.

[0047] The fourth switch K4 is connected at one end to the V2G charging pile 14 and at the other end to the A, B, and C phases of the 380V power distribution line.

[0048] The fifth switch K5 is connected to the DC load 16 at one end and to the A, B and C phases of the 380V power distribution line at the other end.

[0049] The sixth switch K6 is connected at one end to the energy storage battery device 18 and at the other end to the A, B and C phases of the 380V power distribution line.

[0050] The seventh switch K7 is connected at one end to the photovoltaic power generation device 20 and at the other end to the A, B and C phases of the 380V power distribution line.

[0051] Specifically, the data acquisition module 23 includes a sensor 28, a signal conditioning module 29, a data acquisition unit 30, and a communication interface 31. The sensor 28 is connected to the signal conditioning module 29, and the signal conditioning module 29 is connected to the data acquisition unit 30. One end of the data acquisition unit 30 is connected to the data storage module 22, and the other end is connected to the communication interface 31.

[0052] The strategy control module 23 is a control chip. One end of the control chip is connected to the data storage module 22, and the other end is connected to the first switch K1, the second switch K2, the third switch K3, the fourth switch K4, the fifth switch K5, the sixth switch K6, and the seventh switch K7, respectively.

[0053] Furthermore, the data storage module 22 is a data storage device.

[0054] Furthermore, the control principle of the photovoltaic-storage-DC-flexible microgrid energy management device is as follows:

[0055] First, the data acquisition module 21 monitors electrical parameters in real time, such as distribution network voltage / current, bus power, photovoltaic / energy storage status, and load demand. Next, the data storage module 22 stores historical data and real-time monitoring information, providing a basis for strategic control. Finally, based on the collected data, and according to preset strategies (such as power balance, photovoltaic absorption, energy storage optimization, and V2G dispatch), the module controls the switching on and off of switches K1-K7 to manage the power flow of the hardware system.

[0056] Furthermore, the connection between AC bus 10 and distribution network 8 is controlled by the first switch K1. When the DC side (photovoltaic / energy storage) has spare capacity, it can supply power to AC bus 10 through bidirectional DC / AC rectifier 12 to reduce the load on distribution network 8; otherwise, distribution network 8 charges DC bus 13.

[0057] Furthermore, such as Figure 2 As shown, when photovoltaic energy is sufficient, the seventh switch K7 is closed, and the photovoltaic power generation unit 20 discharges through the photovoltaic DC / DC converter 19, prioritizing the supply of power to the DC load 16 and the V2G charging pile 14. The remaining power is stored through the energy storage DC / DC converter 17. When photovoltaic energy is insufficient, the seventh switch K7 is opened, and the sixth switch K6 is closed. The energy storage battery device 18 discharges through the energy storage DC / DC converter 17 to supplement the power of the DC load 16. When the power supply of the energy storage battery device 18 is insufficient, the first switch K1 is closed, and the distribution network 8 and the energy storage battery device 18 jointly supplement the power of the DC load 16.

[0058] Furthermore, based on AC / DC load demand, the opening and closing of the second switch K2 and the fifth switch K5 can be flexibly controlled to dynamically allocate electrical energy (distribution network, photovoltaic, energy storage) and optimize energy utilization efficiency (such as V2G charging during grid off-peak hours and discharging during peak hours to achieve peak shaving and valley filling).

[0059] Furthermore, when the grid is in a low-price period (e.g., low electricity prices at night) or the photovoltaic / energy storage system has surplus power, the fourth switch K4 is closed, and the V2G charging pile 14 draws power from the DC bus 13. Subsequently, the V2G charging pile 14 delivers DC power to the electric vehicle battery, completing charging and energy storage, essentially acting as a "mobile energy storage unit" to store electrical energy. When the grid is in a high-price period (e.g., high electricity prices during the day) or the DC load 16 has high demand, the fourth switch K4 is closed, and the electric vehicle battery discharges: the battery's DC power is directly input into the DC bus via the V2G charging pile 14, supplying the DC load 16 when the fifth switch K5 is closed, reducing the power supply pressure on the distribution network 8. If support for the AC side is required (e.g., high distribution network load), the battery's DC power is converted to AC power via the DC / AC inverter built into the charging pile or with the help of the DC / AC bidirectional rectifier 12 within the system, and fed back to the distribution network 8 through the AC bus 10, realizing energy feedback from "vehicle to grid" and playing a role in peak shaving and valley filling.

[0060] Data storage module 22 uses a data storage device: EM-1000G;

[0061] The strategy control module 23 uses the control chip: TMS320F28377D;

[0062] The DC / AC bidirectional rectifier 12 adopts an AC / DC microgrid rectifier: IPS-9160;

[0063] The step-down DC / DC converter 15 adopts a wide voltage switching step-down DC-DC converter: TX4139;

[0064] The energy storage DC / DC converter 17 adopts a bidirectional energy storage converter: LEG-630K-TT;

[0065] The photovoltaic DC / DC converter 19 adopts a string photovoltaic inverter: SG17T-CN;

[0066] Photovoltaic panel 24 uses photovoltaic panel: TWM-30BHL11A-540W;

[0067] The centralized photovoltaic inverter 25 adopts the centralized photovoltaic inverter: EP-3125-HC-UD;

[0068] Energy storage battery 26 uses lithium iron phosphate battery ERA-5K5;

[0069] Energy storage inverter 27 adopts a three-phase high-voltage energy storage inverter: S6-EH3P(12-20)KH;

[0070] Sensor 28 is a DC voltage sensor: GW16-WBV332U01-S-0.2;

[0071] Signal conditioning module 29 includes an operational amplifier: LM358;

[0072] The data acquisition unit 30 includes a microprocessor MCU: STM32H743;

[0073] Communication interface 31 adopts a short-range communication interface: RS485.

[0074] This utility model discloses an energy management device for a photovoltaic-storage-DC-flexible microgrid, which has the following features:

[0075] 1. It encompasses a hybrid AC / DC power system architecture, integrating various energy sources and equipment such as distribution networks, photovoltaic power generation, energy storage systems, and V2G charging stations. Flexible connection and control of each component are achieved through switches and converters. This highly integrated system effectively combines different energy forms, achieving multi-energy complementarity. Compared to single-energy systems, it has significant advantages in energy utilization efficiency and power supply reliability.

[0076] 2. It possesses comprehensive data acquisition, storage, and strategy control modules. The data acquisition module monitors the operating parameters of various parts of the system in real time, while the strategy control module intelligently adjusts the switch status based on this data, achieving precise management of power flow and distribution. It can dynamically adjust the operating modes of equipment such as V2G charging piles and energy storage systems according to factors such as grid peak-valley electricity prices, renewable energy generation, and load demand, achieving functions such as peak shaving and valley filling, and optimizing energy costs. It features a high degree of intelligence and automation.

[0077] 3. The system is suitable for various application scenarios. Whether it is providing auxiliary support to the power grid in grid-connected mode or providing independent power supply through photovoltaics and energy storage in off-grid mode, it can operate stably and reliably. In particular, the application of V2G charging piles enables electric vehicles to become mobile energy storage units, expanding the system's flexibility and application scope. It has broad application prospects in smart microgrids, distributed energy systems, and other fields, and can meet diverse energy demands.

Claims

1. An energy management device for a photovoltaic-storage-DC-flexible microgrid, characterized in that... The device includes: Data acquisition module (21), data storage module (22), strategy control module (23); The data acquisition module (21) is connected to the data storage module (22), the data storage module (22) is connected to the strategy control module (23), and the strategy control module (23) is connected to the first switch (K1), the second switch (K2), the third switch (K3), the fourth switch (K4), the fifth switch (K5), the sixth switch (K6), and the seventh switch (K7), respectively. One end of the first switch (K1) is connected to the AC bus (10), and the other end of the first switch (K1) is connected to the power distribution line (9); One end of the second switch (K2) is connected to the AC load (11), and the other end of the second switch (K2) is connected to the AC bus (10); One end of the third switch (K3) is connected to the DC bus (13), and the other end of the third switch (K3) is connected to the AC bus (10); One end of the fourth switch (K4) is connected to the V2G charging pile (14), and the other end of the fourth switch (K4) is connected to the DC bus (13); One end of the fifth switch (K5) is connected to the DC load (16), and the other end of the fifth switch (K5) is connected to the DC bus (13); One end of the sixth switch (K6) is connected to the energy storage battery device (18), and the other end of the sixth switch (K6) is connected to the DC bus (13); One end of the seventh switch (K7) is connected to the photovoltaic power generation device (20), and the other end of the seventh switch (K7) is connected to the DC bus (13).

2. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 1, characterized in that: The data acquisition module (21) includes a sensor (28), a signal conditioning module (29), a data acquisition unit (30), and a communication interface (31). The sensor (28) is connected to the signal conditioning module (29), the signal conditioning module (29) is connected to the data acquisition unit (30), and the data acquisition unit (30) is connected to the data storage module (22) and the communication interface (31).

3. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 1, characterized in that: The power distribution network (8) is connected to the other end of the first switch (K1) through the power distribution line (9), and one end of the first switch (K1) is connected to the AC bus (10). The AC bus (10) is connected to the other end of the third switch (K3) through the DC / AC bidirectional rectifier (12), and one end of the third switch (K3) is connected to the DC bus (13). The DC bus (13) is connected to the other end of the fifth switch (K5) through the step-down DC / DC converter (15), and one end of the fifth switch (K5) is connected to the DC load (16). The DC bus (13) is connected to the other end of the sixth switch (K6) through the energy storage DC / DC converter (17), and one end of the sixth switch (K6) is connected to the energy storage battery device (18). The DC bus (13) is connected to the other end of the seventh switch (K7) via the photovoltaic DC / DC converter (19), and one end of the seventh switch (K7) is connected to the photovoltaic power generation device (20).

4. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 3, characterized in that: The DC / AC bidirectional rectifier (12) enables bidirectional energy flow between the AC bus (10) and the DC bus (13), and is used for energy conversion between the distribution network (8) and the DC system.

5. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 3, characterized in that: The step-down DC / DC converter (15) converts a higher DC voltage into a lower DC voltage suitable for the operation of the DC load (16), thus playing a role in voltage matching and regulation.

6. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 3, characterized in that: The energy storage DC / DC converter (17) is used to control the energy exchange between the energy storage battery device (18) and the DC bus (13). During the charging process, the electrical energy of the DC bus (13) is charged into the energy storage battery device (18) with appropriate voltage and current parameters. During the discharging process, the electrical energy of the energy storage battery device (18) is converted into an electrical energy form suitable for the DC bus (13) and output, thereby realizing the charging and discharging control of the energy storage battery device (18).

7. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 3, characterized in that: The photovoltaic DC / DC converter (19) processes the DC power output from the photovoltaic power generation device (20), and achieves maximum power point tracking of the photovoltaic cell by adjusting the voltage and current parameters, and adapts the photovoltaic power to the voltage level of the DC bus (13).

8. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 3, characterized in that: The V2G charging pile (14) realizes bidirectional conversion of electrical energy through a power electronic conversion device; during charging, it rectifies the AC power of the power grid into DC power to charge the vehicle battery; during discharging, it inverts the DC power of the vehicle battery into AC power to feed back to the power grid.

9. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 1, characterized in that: The photovoltaic power generation device (20) includes photovoltaic panels (24) and a centralized photovoltaic inverter (25), with multiple photovoltaic panels (24) connected to the centralized photovoltaic inverter (25).

10. The energy management device for a photovoltaic-storage-DC-flexible microgrid according to claim 1, characterized in that: The energy storage battery device (18) includes an energy storage battery (26) and an energy storage inverter (27), with the energy storage battery (26) connected to the energy storage inverter (27).

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