Stable micro-grid coordination control device and stabilizing method thereof

Abstract

The invention discloses a stable micro-grid coordination control device and a stabilizing method thereof, and relates to the technical field of micro-grid control, the stable micro-grid coordination control device comprises a main control unit, a dynamic networking device, a photovoltaic module and a micro-grid, the main control unit is bidirectionally connected with the dynamic networking device through a 5G network or RS-485, and the dynamic networking device is connected with the photovoltaic module through a power supply. The micro-grid comprises a multi-source cooperative terminal, an environment monitoring terminal, a dual-mode inverter and a plurality of battery modules, the output ends of the photovoltaic modules are electrically connected with the input ends of the battery modules through the dual-mode inverter, the dual-mode inverter is bidirectionally and electrically connected with the multi-source cooperative terminal, and the multi-source cooperative terminal is electrically connected with the environment monitoring terminal. According to the scheme, the problems that when an existing micro-grid system is used in extreme weather such as the northwest region where sand storms frequently occur, a remote communication module is prone to being interfered by sand and dust, so that remote monitoring and control instructions are lost, and stability is poor are solved.

Description

Technical Field

[0001] The present invention relates to the field of microgrid control technology, and in particular to a stable microgrid coordinated control device and a stabilization method thereof. Background Art

[0002] As a carrier for the consumption and management of renewable energy such as wind energy and solar energy, microgrids can integrate the renewable energy power generation system in the region with the user load demand, and can achieve independent management and control of source-load supply and demand in the region without being connected to the main grid.

[0003] The current microgrid control method, such as the announcement number CN221448163U, is named a microgrid coordinated control device, which belongs to the field of microgrid technology. The device includes a communication module, an edge gateway board and a bus board; wherein the bus board includes an Ethernet bus and a CAN bus; the edge gateway board includes an Ethernet interface unit and a control circuit unit for executing the microgrid coordinated control strategy, the control circuit unit communicates with the communication module through the Ethernet bus, and the control circuit unit also communicates with the cloud server through the Ethernet interface unit; the communication module includes a first communication host board and at least one communication terminal board, each communication terminal board includes multiple terminal interfaces, the first communication host board and each communication terminal board are respectively connected to the CAN bus, and the first communication host board is also connected to the Ethernet bus.

[0004] However, when the above-mentioned microgrid system is used in extreme weather conditions, such as the northwest region where sandstorms are frequent, the remote communication module is easily interfered with by sandstorms, resulting in the loss of remote monitoring and control instructions and poor stability. Therefore, we propose a stable microgrid coordinated control device and its stabilization method to solve the above-mentioned problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a stable microgrid coordination control device and a stabilization method thereof, so as to solve the problem that when the existing microgrid system proposed in the above background technology is used in extreme weather, such as the northwest region where sandstorms are frequent, the remote communication module is easily interfered by sand and dust, resulting in the loss of remote monitoring and control instructions and poor stability.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a stable microgrid coordination control device, comprising a main control unit, a dynamic networking device, a photovoltaic module and a microgrid, wherein the main control unit is bidirectionally connected to the dynamic networking device via a 5G network or RS-485, the microgrid comprises a multi-source collaborative terminal, an environmental monitoring terminal, a dual-mode inverter and a battery module, multiple photovoltaic modules and battery modules are provided, and the output end of the photovoltaic module is electrically connected to the input end of the battery module via a dual-mode inverter, the dual-mode inverter is bidirectionally electrically connected to the multi-source collaborative terminal, the environmental monitoring terminal is mounted on the multi-source collaborative terminal, and the output end of the environmental monitoring terminal is electrically connected to the input end of the multi-source collaborative terminal, the dynamic networking device is bidirectionally connected to the multi-source collaborative terminal in the microgrid via a 5G network or RS-485, the multi-source collaborative terminal and the dynamic networking device are both mounted in an underground communication cabin system, and the dynamic networking device is bidirectionally electrically connected to the main grid via an intelligent circuit breaker.

[0007] Preferably, the main control unit is composed of a dual-core heterogeneous processor and an extended storage module. The dual-core heterogeneous processor is mainly used to process control algorithms with high real-time requirements. The processor interface integrates a 5G module and an RS-485 multi-protocol module, and sends control strategies to the multi-energy collaborative terminal through the 5G network or RS-485 to indirectly adjust the photovoltaic output.

[0008] Preferably, the dynamic networking device is composed of an FPGA logic programming module, a local communication gateway and a wireless transceiver module. The dynamic networking device serves as a communication hub, connecting the main control unit and the multi-energy terminal.

[0009] Preferably, the multi-source collaborative terminal is composed of a BMS battery management system, a power distribution controller, a local communication gateway and a wireless transceiver module. The multi-energy collaborative terminal collects real-time data such as the output power and DC side voltage of the dual-mode inverter through the RS-485 interface, and collects environmental data through the environmental monitoring terminal.

[0010] Preferably, the RS-485 communication cable is of an underground structure, covered with double armor, and an inspection well is set every fifty meters in the underground section.

[0011] Preferably, the environmental monitoring terminal includes a sand and dust concentration sensor, a temperature and humidity sensor, and a wind speed and direction sensor. The temperature and humidity sensor can detect the current environmental temperature and humidity conditions and feedback the signal to the temperature control device. The sand and dust concentration sensor detects the sand and dust concentration based on the laser scattering principle, and the wind speed and direction sensor can detect the current environmental wind speed.

[0012] Preferably, the dynamic networking device and the multi-source collaborative terminal are both installed in an underground communication cabin system. The underground communication cabin system includes an underground cabin and a hydraulic lifting device located in the underground cabin. The lifting end of the hydraulic lifting device is transmission-connected to the dynamic networking device and the multi-source collaborative terminal. A temperature control device is additionally installed in the underground cabin of the multi-source collaborative terminal, and the temperature control device is composed of a heat dissipation module and an electric heating module.

[0013] Preferably, the dual-mode inverter supports VSG and droop control dual modes.

[0014] Preferably, the battery module is a hybrid energy storage of lithium iron phosphate batteries and liquid flow batteries, wherein the lithium iron phosphate batteries account for 60% and the liquid flow batteries account for 40%.

[0015] Preferably, the stabilization method of the stable microgrid coordinated control device comprises the following steps:

[0016] Step 1: Under normal circumstances, the dynamic networking equipment is connected to the main grid through an intelligent circuit breaker. The synchronous transformer ensures voltage and frequency matching and serves as a communication hub, connecting the main control unit and multi-energy terminals. The main control unit issues a grid connection command via the 5G network, making the microgrid a dispatchable unit of the main grid. The microgrid receives the main grid command through the dynamic networking equipment. At this time, the dual-mode inverter is in droop mode and connected to the main grid, realizing bidirectional power flow and supporting the connection of surplus power to the grid or drawing power from the main grid when there is a power shortage.

[0017] Step 2: When in the following state, the main control unit sends a command to switch to island mode:

[0018] S1: When the dynamic networking device detects that the intelligent circuit breaker has tripped, physically disconnecting from the main network, or the 5G network packet loss rate is greater than 20%, the dynamic networking device directly sends an island request to the main control unit;

[0019] S2: When the dust concentration sensor or wind speed and direction sensor on the multi-source collaborative terminal detects that the dust concentration or wind speed is greater than the threshold, the multi-source collaborative terminal feeds back a signal to the dynamic networking device, and the dynamic networking device sends an island request to the main control unit.

[0020] Step 3: After receiving the islanding request signal, the main control unit issues a command to the dynamic networking device and the microgrid to switch to RS-485 for signal transmission. The dynamic networking device sends a signal to the multi-energy terminal based on the FPGA logic programming module, converts the protocol state, and instructs the multi-energy terminal to switch the dual-mode inverter to VSG mode. The energy storage system uses lithium iron phosphate batteries for primary frequency regulation and supports voltage in constant power mode.

[0021] Step 4: In the S2 state, the main control unit further drives the underground communication cabin system to operate, retracting the hydraulic lifting device so that the dynamic networking equipment and the multi-source collaborative terminal are buried underground;

[0022] Step 5: When the multi-source collaborative terminal is in the underground state, the temperature of the underground cabin is detected by the temperature and humidity sensor. When the temperature is lower than 20 degrees Celsius, the feedback signal is sent to the temperature control device to drive the electric heating module to operate. When the temperature is higher than 50 degrees Celsius, the feedback signal is sent to the temperature control device to drive the heat dissipation module to operate.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The microgrid of the present invention has an adaptive island mode, which has two triggering conditions:

[0025] First, when the dynamic networking device detects that the intelligent circuit breaker has tripped, physically disconnecting the main network, or the 5G network packet loss rate is greater than 20%, the dynamic networking device directly sends an islanding request to the main control unit;

[0026] Second, by additionally equipping the multi-source collaborative terminal with an environmental monitoring terminal, the dust concentration sensor and wind speed and direction sensor in the environmental monitoring terminal can be used to detect the dust concentration and wind speed in the current environment. When the dust concentration sensor or wind speed and direction sensor on the multi-source collaborative terminal detects that the dust concentration or wind speed is greater than the threshold, the multi-source collaborative terminal feeds back a signal to the dynamic networking device, which then sends an islanding request to the main control unit.

[0027] After receiving the signal, the main control unit issues an islanding command to switch the dynamic networking equipment and microgrid to RS-485 for signal transmission. It also instructs the multi-energy terminal to switch the dual-mode inverter to VSG mode, allowing the energy storage system to support voltage in constant power mode.

[0028] In the second case caused by a harsh environment, the master control terminal will further drive the operation of the underground communication cabin system, retracting the hydraulic lifting device to bury the dynamic networking equipment and multi-source collaborative terminal underground, so that the equipment can be protected from wind and sand erosion and its protective life span can be tripled.

[0029] This solves the problem that when the existing microgrid system is used in extreme weather conditions, such as the northwest region where sandstorms are frequent, the remote communication module is easily interfered by sand and dust, resulting in loss of remote monitoring and control instructions and poor stability.

[0030] (2) Since the multi-energy collaborative terminal connects to distributed energy, executes power distribution and control strategies, and carries more components, a temperature control device is additionally installed in the underground communication cabin system of the multi-energy collaborative terminal. It can be linked with the temperature and humidity sensors on the multi-source collaborative terminal. When the multi-source collaborative terminal is in the underground state, the temperature and humidity sensors can detect the temperature of the underground cabin. When the temperature is lower than 20 degrees Celsius, the feedback signal is sent to the temperature control device to drive the electric heating module to operate to avoid freezing of the components. When the temperature is higher than 50 degrees Celsius, the feedback signal is sent to the temperature control device to drive the heat dissipation module to cool the components. The use of the underground communication cabin system and the improvement of the conventional RS-485 communication cable to the underground structure, although the initial investment increases, the long-term operation and maintenance costs are significantly reduced due to the significant reduction in failure rate.

[0031] (3) The inverter of the present application adopts a dual-mode inverter, which supports VSG and droop control dual modes;

[0032] When operating in grid-connected mode, the inverter is in droop mode, which can dynamically adjust the droop coefficient based on the energy storage SOC state, giving priority to low SOC energy storage, such as lithium batteries, to participate in frequency modulation;

[0033] When operating in island mode, the inverter switches to VSG mode, reducing the frequency of energy storage charging and discharging through the inertial support of VSG, and the SOC fluctuation rate drops by 15%, extending battery life.

[0034] (4) By setting the battery module of the energy storage system to a hybrid energy storage of lithium iron phosphate batteries and flow batteries;

[0035] In the grid-connected state, the lithium iron phosphate battery and liquid flow battery of the battery module work together to store energy. Although the internal liquid flow battery has a slow response, it has a large storage capacity. Due to its modular design, it can be flexibly expanded according to actual needs. In the island mode, in order to meet short-term high power requirements, the BMS battery management system switches to lithium iron phosphate batteries for the main frequency regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the overall structure of the present invention; DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0038] See also Figure 1, an embodiment provided by the present invention: a stable microgrid coordination control device, including a main control unit, a dynamic networking device, a photovoltaic module and a microgrid, the main control unit is bidirectionally connected to the dynamic networking device via a 5G network or RS-485, the microgrid includes a multi-source collaborative terminal, an environmental monitoring terminal, a dual-mode inverter and a battery module, the photovoltaic module and the battery module are both provided in plurality, and the output end of the photovoltaic module is electrically connected to the input end of the battery module via the dual-mode inverter, the dual-mode inverter is bidirectionally electrically connected to the multi-source collaborative terminal, the environmental monitoring terminal is mounted on the multi-source collaborative terminal, and the environmental monitoring terminal The output end of the terminal is electrically connected to the input end of the multi-source collaborative terminal, the dynamic networking device is bidirectionally connected to the multi-source collaborative terminal in the microgrid through a 5G network or RS-485, the multi-source collaborative terminal and the dynamic networking device are both mounted in an underground communication cabin system, the dynamic networking device is bidirectionally electrically connected to the main grid through an intelligent circuit breaker, the main control unit is composed of a dual-core heterogeneous processor and an extended storage module, the dynamic networking device is composed of an FPGA logic programming module, a local communication gateway and a wireless transceiver module, and the multi-source collaborative terminal is composed of a BMS battery management system, a power distribution controller, a local communication gateway and a wireless transceiver module;

[0039] The dual-core heterogeneous processor is mainly used to process control algorithms with high real-time requirements. The processor interface integrates a 5G module and an RS-485 multi-protocol module. It sends control strategies to multi-energy collaborative terminals via the 5G network or RS-485, indirectly adjusting the photovoltaic output. Photovoltaic data is transmitted simultaneously via RS-485 (local) and 5G (remote), and automatically switches if either link is interrupted. The extended storage module on the dual-core heterogeneous processor is mainly used to store local photovoltaic output and load history data, enabling local processing of distributed accounting and reducing dependence on the cloud.

[0040] The dynamic networking device serves as a communication hub, connecting the main control unit and multiple energy terminals. Based on the FPGA logic programming module, it can realize multi-protocol conversion and topology reconstruction. The local communication gateway and wireless transceiver module can be connected to the 5G network and RS-485 respectively.

[0041] The multi-energy collaborative terminal collects real-time data such as the dual-mode inverter output power and DC side voltage through the RS-485 interface, and collects environmental data through the environmental monitoring terminal. The main control unit receives data every 5 minutes to update the photovoltaic prediction status. After receiving the logic array sent by the FPGA logic programming module, the power distribution controller can dynamically allocate the energy storage charging and discharging power according to the photovoltaic output and load demand.

[0042] Furthermore, the RS-485 communication cable is an underground structure with double armor covering. Inspection wells are set up every fifty meters in the underground section. The underground structure increases the wind and sand resistance of the RS-485 line by three times and significantly reduces the failure rate.

[0043] Furthermore, the environmental monitoring terminal includes a dust concentration sensor, a temperature and humidity sensor, and a wind speed and direction sensor;

[0044] The temperature and humidity sensor can detect the current ambient temperature and humidity conditions and feed back the signal to the temperature control device. The dust concentration sensor detects the dust concentration based on the laser scattering principle, while the wind speed and direction sensor can detect the current ambient wind speed. The dust concentration sensor detects concentrations greater than 500μg / m 3 Or when the wind speed and direction sensor detects a wind speed greater than 20m / s, the main control unit switches to the harsh environment emergency mode. At this time, the wireless transmission effect is poor, the underground communication line activates the redundant bypass, and the energy storage prioritizes supporting the critical load

[0045] Furthermore, the dynamic networking device and the multi-source collaborative terminal are both mounted in an underground communication cabin system. The underground communication cabin system includes an underground cabin and a hydraulic lifting device located in the underground cabin. The lifting end of the hydraulic lifting device is transmission-connected to the dynamic networking device and the multi-source collaborative terminal. A temperature control device is additionally installed in the underground cabin of the multi-source collaborative terminal. The temperature control device is composed of a heat dissipation module and an electric heating module.

[0046] When the dust concentration sensor or wind speed and direction sensor on the multi-source collaborative terminal detects that the dust concentration or wind speed is greater than the threshold, the multi-source collaborative terminal feeds back a signal to the dynamic networking device, which sends an island request to the main control unit. After receiving the signal, the main control unit issues an instruction to switch the dynamic networking device and the microgrid to RS-485 for signal transmission, and instructs the multi-energy terminal to switch the dual-mode inverter to VSG mode, so that the energy storage system supports the voltage in constant power mode. At the same time, the main control unit further drives the underground communication cabin system to operate, retracts the hydraulic lifting device to put the dynamic networking device and the multi-source collaborative terminal into an underground state. The cabin is made of stainless steel and covered with epoxy resin coating, which has good corrosion resistance, so that the equipment can avoid wind and sand erosion, and the protection life is increased by 3 times. The terminal connects to distributed energy and executes power distribution and control strategies, so it is equipped with more components. Therefore, a temperature control device is additionally installed in the underground communication cabin system of the multi-energy collaborative terminal, which can be linked with the temperature and humidity sensors on the multi-source collaborative terminal. When the multi-source collaborative terminal is in an underground state, the temperature and humidity sensors can detect the temperature of the underground cabin. When the temperature is lower than 20 degrees Celsius, the feedback signal is sent to the temperature control device to drive the electric heating module to operate to avoid freezing of the components. When the temperature is higher than 50 degrees Celsius, the feedback signal is sent to the temperature control device to drive the heat dissipation module to cool the components. The use of an underground communication cabin system and the improvement of conventional RS-485 communication cables to underground structures, although the initial investment increases by 15% to 20%, the long-term operation and maintenance costs are reduced by 40% due to the significant reduction in failure rate.

[0047] Furthermore, the dual-mode inverter supports both VSG and droop control modes;

[0048] When operating in grid-connected mode, the inverter is in droop mode, which can dynamically adjust the droop coefficient based on the energy storage SOC state, giving priority to low SOC energy storage, such as lithium batteries, to participate in frequency modulation;

[0049] When operating in island mode, the inverter switches to VSG mode, reducing the frequency of energy storage charging and discharging through the inertial support of VSG, and the SOC fluctuation rate drops by 15%, extending battery life.

[0050] Furthermore, the battery module is a hybrid energy storage system of lithium iron phosphate batteries and flow batteries, of which lithium iron phosphate batteries account for 60% and flow batteries account for 40%;

[0051] In the grid-connected state, the lithium iron phosphate battery and liquid flow battery of the battery module work together to store energy. Although the internal liquid flow battery has a slow response, it has a large storage capacity. Due to its modular design, it can be flexibly expanded according to actual needs. In the island mode, in order to meet short-term high power requirements, the BMS battery management system switches to lithium iron phosphate batteries for the main frequency regulation.

[0052] Furthermore, a stabilization method for a stable microgrid coordinated control device includes the following steps:

[0053] Step 1: Under normal circumstances, the dynamic networking equipment is connected to the main grid through an intelligent circuit breaker. The synchronous transformer ensures voltage and frequency matching and serves as a communication hub, connecting the main control unit and multi-energy terminals. The main control unit issues a grid connection command via the 5G network, making the microgrid a dispatchable unit of the main grid. The microgrid receives the main grid command through the dynamic networking equipment. At this time, the dual-mode inverter is in droop mode and connected to the main grid, realizing bidirectional power flow and supporting the connection of surplus power to the grid or drawing power from the main grid when there is a power shortage.

[0054] Step 2: When in the following state, the main control unit sends a command to switch to island mode:

[0055] S1: When the dynamic networking device detects that the intelligent circuit breaker has tripped, physically disconnecting from the main network, or the 5G network packet loss rate is greater than 20%, the dynamic networking device directly sends an island request to the main control unit;

[0056] S2: When the dust concentration sensor or wind speed and direction sensor on the multi-source collaborative terminal detects that the dust concentration or wind speed is greater than the threshold, the multi-source collaborative terminal feeds back a signal to the dynamic networking device, and the dynamic networking device sends an island request to the main control unit.

[0057] Step 3: After receiving the islanding request signal, the main control unit issues a command to the dynamic networking device and the microgrid to switch to RS-485 for signal transmission. The dynamic networking device sends a signal to the multi-energy terminal based on the FPGA logic programming module, converts the protocol state, and instructs the multi-energy terminal to switch the dual-mode inverter to VSG mode. The energy storage system uses lithium iron phosphate batteries for primary frequency regulation and supports voltage in constant power mode.

[0058] Step 4: In the S2 state, the main control unit further drives the underground communication cabin system to operate, retracting the hydraulic lifting device so that the dynamic networking equipment and the multi-source collaborative terminal are buried underground;

[0059] Step 5: When the multi-source collaborative terminal is in the underground state, the temperature of the underground cabin is detected by the temperature and humidity sensor. When the temperature is lower than 20 degrees Celsius, the feedback signal is sent to the temperature control device to drive the electric heating module to operate. When the temperature is higher than 50 degrees Celsius, the feedback signal is sent to the temperature control device to drive the heat dissipation module to operate.

[0060] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A stable microgrid coordination control device, comprising a main control unit, a dynamic networking device, a photovoltaic module, and a microgrid, characterized in that: The main control unit is bidirectionally connected to the dynamic networking device through a 5G network or RS-485. The microgrid includes a multi-source collaborative terminal, an environmental monitoring terminal, a dual-mode inverter and a battery module. There are multiple photovoltaic modules and battery modules, and the output end of the photovoltaic module is electrically connected to the input end of the battery module through a dual-mode inverter. The dual-mode inverter is bidirectionally electrically connected to the multi-source collaborative terminal. The environmental monitoring terminal is mounted on the multi-source collaborative terminal, and the output end of the environmental monitoring terminal is electrically connected to the input end of the multi-source collaborative terminal. The dynamic networking device is bidirectionally connected to the multi-source collaborative terminal in the microgrid through a 5G network or RS-485. The multi-source collaborative terminal and the dynamic networking device are both mounted in an underground communication cabin system. The dynamic networking device is bidirectionally electrically connected to the main grid through an intelligent circuit breaker.

2. A stable microgrid coordinated control device according to claim 1, characterized in that: The main control unit is composed of a dual-core heterogeneous processor and an extended storage module.

3. A stable microgrid coordinated control device according to claim 2, characterized in that: The dynamic networking device is composed of an FPGA logic programming module, a local communication gateway and a wireless transceiver module.

4. A stable microgrid coordinated control device according to claim 3, characterized in that: The multi-source collaborative terminal is composed of a BMS battery management system, a power distribution controller, a local communication gateway and a wireless transceiver module.

5. A stable microgrid coordinated control device according to claim 4, characterized in that: The RS-485 communication cable is of underground structure, covered with double armor, and an inspection well is set every fifty meters in the underground section.

6. A stable microgrid coordinated control device according to claim 5, characterized in that: The environmental monitoring terminal includes a sand and dust concentration sensor, a temperature and humidity sensor, and a wind speed and direction sensor.

7. A stable microgrid coordinated control device according to claim 6, characterized in that: The dynamic networking equipment and the multi-source collaborative terminal are both installed in an underground communication cabin system. The underground communication cabin system includes an underground cabin and a hydraulic lifting device located in the underground cabin. The lifting end of the hydraulic lifting device is transmission-connected to the dynamic networking equipment and the multi-source collaborative terminal. A temperature control device is additionally installed in the underground cabin of the multi-source collaborative terminal. The temperature control device is composed of a heat dissipation module and an electric heating module.

8. A stable microgrid coordinated control device according to claim 7, characterized in that: The dual-mode inverter supports VSG and droop control dual modes.

9. A stable microgrid coordinated control device according to claim 8, characterized in that: The battery module is a hybrid energy storage of lithium iron phosphate batteries and flow batteries, of which lithium iron phosphate batteries account for 60% and flow batteries account for 40%.

10. A method for stabilizing a stable microgrid coordinated control device, implemented based on the stable microgrid coordinated control device according to claim 9, characterized in that: The following steps are involved: Step 1: Under normal circumstances, the dynamic networking equipment is connected to the main grid through an intelligent circuit breaker. The synchronous transformer ensures voltage and frequency matching and serves as a communication hub, connecting the main control unit and multi-energy terminals. The main control unit issues a grid connection command via the 5G network, making the microgrid a dispatchable unit of the main grid. The microgrid receives the main grid command through the dynamic networking equipment. At this time, the dual-mode inverter is in droop mode and connected to the main grid, realizing bidirectional power flow and supporting the connection of surplus power to the grid or drawing power from the main grid when there is a power shortage. Step 2: When in the following state, the main control unit sends a command to switch to island mode: S1: When the dynamic networking device detects that the intelligent circuit breaker has tripped, physically disconnecting from the main network, or the 5G network packet loss rate is greater than 20%, the dynamic networking device directly sends an island request to the main control unit; S2: When the dust concentration sensor or wind speed and direction sensor on the multi-source collaborative terminal detects that the dust concentration or wind speed is greater than the threshold, the multi-source collaborative terminal feeds back a signal to the dynamic networking device, and the dynamic networking device sends an island request to the main control unit. Step 3: After receiving the islanding request signal, the main control unit issues a command to the dynamic networking device and the microgrid to switch to RS-485 for signal transmission. The dynamic networking device sends a signal to the multi-energy terminal based on the FPGA logic programming module, converts the protocol state, and instructs the multi-energy terminal to switch the dual-mode inverter to VSG mode. The energy storage system uses lithium iron phosphate batteries for primary frequency regulation and supports voltage in constant power mode. Step 4: In the S2 state, the main control unit further drives the underground communication cabin system to operate, retracting the hydraulic lifting device so that the dynamic networking equipment and the multi-source collaborative terminal are buried underground; Step 5: When the multi-source collaborative terminal is in the underground state, the temperature of the underground cabin is detected by the temperature and humidity sensor. When the temperature is lower than 20 degrees Celsius, the feedback signal is sent to the temperature control device to drive the electric heating module to operate. When the temperature is higher than 50 degrees Celsius, the feedback signal is sent to the temperature control device to drive the heat dissipation module to operate.

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