Microgrid system of lunar scientific research station based on multi-source access electric energy router

Abstract

The invention discloses a lunar scientific research station micro-grid system based on a multi-source access electric energy router, and belongs to the technical field of deep space exploration and micro-grid energy supply systems. The micro-grid system comprises a medium-large micro-grid and a plurality of small micro-grids, and the medium-large micro-grid takes a high-voltage alternating-current backbone network as a framework and is connected with the small micro-grids; each micro-grid comprises a plurality of electric energy routers, and the electric energy routers are connected in parallel through high-voltage alternating-current ports; the electric energy router is connected with various distributed power supplies through a plurality of ports, supplies power to a load, and is responsible for scheduling and managing multi-source energy; and each small micro-grid performs micro-source configuration and port and capacity configuration of the electric energy router according to the load and in-situ resource characteristics of the power supply area of the small micro-grid. A quasi Z source converter and high-frequency transformer technology is adopted to realize cross-voltage-level energy efficient conversion, the flexibility and robustness of an energy system are remarkably improved, and theoretical support and engineering reference are provided for all-weather autonomous operation of a lunar scientific research station.

Description

Technical Field

[0001] The present invention belongs to the technical field of deep space exploration and microgrid energy supply systems, and specifically relates to a lunar research station microgrid system based on a multi-source access power router. Background Art

[0002] With the rapid development of aerospace and deep space exploration technologies, humanity's exploration of the rich natural resources of the Moon has entered a new phase. As a major pioneer in human space exploration, the design and control of energy systems for lunar research stations have become a focus of research in the global aerospace community. Research institutions worldwide have proposed different concepts for the construction of lunar research stations. The United States has proposed the Artemis program, which aims to send astronauts to the Moon and return them safely, while also establishing a regular presence. The program proposes a hybrid power supply system dominated by nuclear power. The European Space Agency has proposed the "Moon Village" concept, aiming to build an open and sustainable lunar base for scientific research and exploration. It also plans to construct a green energy network that optimizes carbon emissions, centered around the recycling of hydrogen energy.

[0003] During the construction and operation of a lunar research station, power supply is a critical requirement for ensuring its operation. Therefore, prior to construction, it is necessary to study the load characteristics of the lunar research station's application scenarios and the distribution of in-situ resources. This, combined with the impact of the lunar surface application environment, should lead to the construction of a lunar power supply system that utilizes multiple energy sources suitable for the lunar environment. This will provide theoretical and technical support for the construction of the lunar research station's energy system.

[0004] The lunar research station's energy systems are generally divided into large, medium, and small energy systems. The large energy system is responsible for powering the main research station, featuring all-weather, high-load, and long-term operation, with an output power of ≥20kW. The medium energy system is responsible for providing energy for spacecraft performing their missions, with outputs of 1kW and 400W for spacecraft operating in the illuminated area and all-weather spacecraft, respectively. The small energy system is responsible for powering the small spacecraft, with an output power of ≤400W. Power is transferred between the systems via wireless and wired energy transmission.

[0005] The power system of the lunar research station needs to be designed based on the equipment type, power requirements, and transmission distance of each system, combined with existing insulation technology to design a variety of voltage level power supply networks that are suitable for equipment operation, thereby ensuring the efficiency and reliability of the energy system and facilitating further expansion. The power supply voltage levels are divided into the following three categories based on the tasks of the research station equipment:

[0006] Low-voltage systems (12V-48V DC): These voltage levels are designed for low-power devices (<1kW) and short-distance transmission, primarily used to power communication modules, sensors, and small control systems. Medium-voltage systems (100V-400V DC): These voltage levels are suitable for devices with medium power requirements (1-10kW) and are primarily used to power machines involved in survey operations. Examples include robotic arms and drilling rigs, requiring a balance between transmission efficiency and operational flexibility. High-voltage systems (1kV-10kV): These voltage levels serve high-power devices (>10kW) and long-distance transmission, ensuring the stable operation of large-scale infrastructure crucial to scientific research stations. For example, hydrogen production plants and smelting plants utilize high-voltage direct current transmission to reduce line losses. Voltage grading design comprehensively considers power matching and transmission losses. Low voltage ensures the stable operation of precision equipment, medium voltage drives the efficient operation of mechanical equipment, and high voltage supports the long-term operation of large-scale infrastructure, thereby forming a well-defined, secure, and reliable lunar energy network.

[0007] Overall, the lunar research station's electricity demand is characterized by multiple scenarios and high fluctuations, depending on its changing functions at different stages. Given the station's high power demands, complex operating environment, multi-scenario operating conditions, and divergent power consumption and generation, the system requires scalability, versatility, interchangeability, and autonomous operation. The system therefore utilizes distributed energy resources.

[0008] At the same time, due to the lunar environment and resource distribution, the divergence of power consumption and power generation at the research station, as well as the long-term polar day and night phenomenon and the difficulty in energy replenishment, the distributed energy system of the lunar research station should focus on solving the following problems:

[0009] 1) Energy distance and transmission efficiency issues

[0010] The proper operation of a lunar research station requires multiple energy nodes, such as photovoltaic arrays, small nuclear reactors, and fuel cells. Given the complex lunar terrain and extreme temperature fluctuations, these nodes are typically located in diverse locations. Ensuring efficient energy transmission between these nodes is a key issue.

[0011] 2) Stability of energy supply

[0012] The lunar research station's application goal is to be a comprehensive scientific research facility capable of long-term autonomous operation with short-term human intervention. This requires a power supply system with intelligent operation and high reliability. This requires that the station's scientific research efficiency be taken into consideration and that power supply be guaranteed around the clock.

[0013] 3) Complex energy coordination and scheduling

[0014] The energy system is influenced by the diurnal cycle, relying on solar power during polar day and nuclear power and energy storage during polar night, requiring seamless switching between these two power supply modes. Power generation varies, with varying effectiveness. For example, nuclear power offers stable and continuous generation but slow startup, while energy storage offers fast response but limited capacity. This requires a unified scheduling interface and the design of a combination strategy.

[0015] Therefore, a lunar research station microgrid system based on multi-source access power router is proposed. Summary of the Invention

[0016] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a lunar research station microgrid system based on a multi-source access power router, which solves the problems in the prior art.

[0017] The purpose of the present invention can be achieved through the following technical solutions:

[0018] The lunar research station microgrid system based on multi-source access power routers includes: medium and large microgrids and multiple small microgrids. The medium and large microgrids use a high-voltage AC backbone network as the skeleton to connect the small microgrids; each microgrid includes multiple power routers, which are connected in parallel through high-voltage AC ports; the power routers connect various distributed power sources through multiple ports, supply power to loads, and are responsible for the scheduling and management of multi-source energy; each small microgrid configures micro sources, as well as the ports and capacity of the power routers according to the load and in-situ resource characteristics of its power supply area.

[0019] Furthermore, different ports of the power router are respectively connected to a load, an energy storage module, a fuel cell, a water electrolysis hydrogen production module, a nuclear power generation module and a photovoltaic.

[0020] Furthermore, small microgrids give priority to using photovoltaic power generation as the basic source of clean energy supply, directly supplying power to the load and charging the energy storage module when there is sufficient sunlight; when there is insufficient sunlight or the moon enters the night period, the nuclear power generation module and the fuel cell serve as the main power supply modules; the water electrolysis hydrogen production module produces hydrogen and stores it for use in the fuel cell when energy is abundant; the energy router can intelligently switch the power output path according to load demand, energy supply and energy storage status, and realize energy optimization distribution and power balance control.

[0021] Furthermore, the voltage of the high voltage alternating current is 3 kV and the frequency is 1 kHz.

[0022] Furthermore, the ports of the power router are low-voltage DC power ports, the voltage of which is less than or equal to 100V; and all low-voltage DC power ports adopt a modular design and use the same topology.

[0023] Furthermore, the power router is provided with a quasi-Z source inverter and a high-frequency transformer. The quasi-Z source inverter converts direct current into high-frequency alternating current, which is then converted into 3kV alternating current through the high-frequency transformer.

[0024] Furthermore, in the power router, the quasi-Z-source inverter converts DC power into 200V / 1kHz high-frequency AC power, and then obtains 3kV / 1kHz AC power through a high-frequency transformer with a transformation ratio of 1:15.

[0025] Furthermore, the quasi-Z-source inverter includes an inverter bridge and a quasi-Z-source network located before the inverter bridge; the quasi-Z-source network includes two inductors L1 and L2 of the same size and two capacitors C1 and C2 of the same size.

[0026] Furthermore, the working state of the quasi-Z-source inverter is divided into a through state and a non-through state:

[0027] In the direct-through state of the quasi-Z-source inverter, the switches of the inverter bridge are turned on at the same time, forming a short-circuit state, which is used for energy storage and conversion of the quasi-Z-source network, increasing the voltage of the DC bus and achieving voltage boosting;

[0028] In the non-shoot-through state of the quasi-Z-source inverter, the switch tube operates according to the SPWM control strategy to perform DC-AC conversion, transfer the energy stored in the quasi-Z-source network to the load, and generate an output AC voltage.

[0029] A lunar research station equipped with the above-mentioned microgrid system.

[0030] Beneficial effects of the present invention:

[0031] 1. This invention uses a high-voltage AC backbone network (3kV / 1kHz) to build medium- and large-scale microgrids, enabling efficient energy transmission between long-distance regions. Each power router uses a quasi-Z-source inverter plus a high-frequency transformer structure to boost 100V DC to 3kV AC, reducing transmission line weight and energy consumption. The high-frequency design also reduces system size and improves adaptability to complex lunar terrain.

[0032] 2. The small microgrid of the present invention supports multi-source coordinated energy supply, with photovoltaic power supply taking priority. It automatically switches to nuclear power and fuel cell power supply during polar night. The water electrolysis hydrogen production module can produce hydrogen when there is excess photovoltaic power to provide continued power supply for the fuel cell. The power router ensures voltage stability and load continuity through status monitoring and dynamic scheduling.

[0033] 3. The multi-layer control architecture of the present invention supports port-level power control, voltage control, and collaborative control. The energy router's perception and regulation capabilities enable the system to achieve source-load path optimization and dynamic power balance based on load demand, energy storage status, and energy availability. It supports multiple operating modes such as multi-module parallel connection and constant voltage / constant power mode to adapt to different application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0035] Figure 1 This is a diagram of the microgrid system architecture of the lunar research station of the present invention;

[0036] Figure 2 This is the topology diagram of the quasi-Z-source inverter of the present invention;

[0037] Figure 3 This is the direct equivalent circuit diagram of the quasi-Z-source inverter of the present invention;

[0038] Figure 4 This is the non-shoot-through equivalent circuit diagram of the quasi-Z-source inverter of the present invention;

[0039] Figure 5 This is the topology diagram of the lunar power router based on the quasi-Z source of the present invention;

[0040] Figure 6 This is a control architecture diagram of the microgrid system of the lunar research station of the present invention;

[0041] Figure 7 It is a simulation result diagram of different micro-sources under different working conditions;

[0042] Figure 8 It is the three-phase line voltage waveform in VF control mode;

[0043] Figure 9 This is the waveform of the transformer primary side phase current in VF control mode;

[0044] Figure 10 This is the waveform of the transformer primary side phase current under PQ control mode;

[0045] Figure 11 It is the output power waveform in PQ control mode. DETAILED DESCRIPTION

[0046] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0047] Example 1

[0048] like Figure 1 As shown in the figure, the lunar research station microgrid system based on multi-source access power routers includes: medium and large microgrids and multiple small microgrids. The medium and large microgrids use a high-voltage AC (AC, 3kV / 1kHz) backbone network as the skeleton to connect the small microgrids; each microgrid includes multiple power routers, and the power routers are connected in parallel through 3kV / 1kHz AC ports; the power routers connect various distributed power sources through multiple ports, supply power to loads, and are responsible for the scheduling and management of multi-source energy; each small microgrid configures micro sources and the ports and capacity of the power routers according to the load and in-situ resource characteristics of its power supply area.

[0049] The Zhongda Microgrid utilizes a high-voltage AC (3kV / 1kHz) backbone network to connect various smaller microgrids, forming a comprehensive energy supply network covering the entire research station region. The ring-shaped backbone structure improves the system's fault tolerance and energy flow flexibility, effectively addressing changes in the overall load scale of the lunar research station and energy imbalances between regions. The backbone network supports high-power energy transmission across regions and achieves dynamic energy coupling with each DC subgrid (100V), ensuring energy coordination and stable operation of each subsystem under different operating conditions.

[0050] The Energy Router (EER) includes multiple low-voltage DC power ports for connecting to various distributed power sources and providing low-voltage power to loads. The low-voltage DC power ports utilize a modular design and a common topology, facilitating assembly, expansion, and maintenance. Energy Routers are connected in parallel via high-voltage AC ports to form a small microgrid. The low-voltage ports operate at voltages of 100V or less and automatically adjust based on the voltage requirements of the micropower source and loads. The high-voltage side utilizes a 3kV AC connection to reduce transmission losses and transmission line weight.

[0051] In this embodiment, the different ports of the energy router are connected to loads, energy storage modules, fuel cells, water electrolysis hydrogen production modules, nuclear power generation modules, and photovoltaics. Regarding energy supply strategy, the small microgrid prioritizes photovoltaic power generation as its primary clean energy source, directly powering the load and charging the energy storage module when sunlight is sufficient. When sunlight is insufficient or during moonlit nights, the nuclear power generation module and fuel cells take over as the primary power supply, ensuring the continuity and stability of the energy supply. Meanwhile, the water electrolysis hydrogen production module produces and stores hydrogen when energy is abundant, ready for use by the fuel cell when needed, thus achieving spatiotemporal energy transfer and regulation. As the core hub of the small microgrid, the energy router is responsible for the flexible scheduling and management of multiple energy sources. It can intelligently switch power output paths based on load demand, energy supply conditions, and energy storage status, and achieve optimal energy distribution and power balance control.

[0052] Since the low-voltage port of the power router is generally 100V or below, and the high-voltage port is connected to a 3kV / 1kHz medium-to-large microgrid, the lunar power router must achieve power conversion from the low-voltage port to 3kV AC. When using AC transmission, the topology for boosting low-voltage DC to high-voltage AC is currently mainly a two-stage structure, with a first stage of DC boost and a first stage of inverter. Due to the high AC voltage, the inverter needs to adopt a multi-level topology or a module cascade topology. However, the two-stage conversion structure is less efficient. In addition, the multi-level or module cascade topology uses more power devices and capacitors, resulting in a larger converter size and lower equipment reliability. Therefore, this embodiment adopts a topology based on a quasi-Z-source inverter. The quasi-Z-source inverter can boost low-voltage DC to high-voltage AC through a single stage of conversion, but the step-up ratio is usually less than 3 times. In this regard, considering that the increase in AC frequency in the application scenario of the lunar microgrid can also reduce the size of the equipment, since the volume of the transformer decreases with the increase of frequency, and the volume weight is almost inversely proportional to the frequency, a topology combining a quasi-Z-source inverter and a 1kHz transformer is adopted.

[0053] The topology of the quasi-Z source inverter is as follows: Figure 2As shown, it is formed by adding a quasi-Z-source network in front of a traditional inverter bridge. It includes two inductors L1 and L2 of equal size, two capacitors C1 and C2 of equal size, a switch S7, a full-bridge inverter, and an output terminal. Inductors L1, L2, and switch S7 are connected in series between the positive terminal of the power supply and the upper bridge arm. One end of capacitor C1 is connected between switch S7 and inductor L2, and the other end is located in the lower bridge arm. Capacitor C2 is connected in parallel with switch S7 and inductor L2, connected between the two inductors. It can complete DC-AC conversion in a single-stage structure. In addition to the non-zero voltage vector and zero voltage vector of a traditional inverter, the quasi-Z-source inverter also has a direct-through vector that can simultaneously turn on both upper and lower switches in the same bridge arm. It is precisely because of the direct-through vector that the quasi-Z-source inverter can achieve the buck-boost function.

[0054] The working states of the quasi-Z-source inverter are mainly divided into the through state and the non-through state:

[0055] In the shoot-through state of a quasi-Z-source inverter, the switches in all the inverter arms are simultaneously turned on, creating a short-circuit condition. This special operating mode is prohibited in traditional inverters. However, in a quasi-Z-source inverter, the shoot-through state is used to store and convert energy in the quasi-Z-source network (inductors and capacitors), increasing the DC bus voltage and achieving a voltage boost function. This shoot-through state allows the system to store energy and increase the output voltage, eliminating the need for additional boost components.

[0056] The non-shoot-through state operates similarly to a traditional inverter. The switches operate according to a conventional SPWM control strategy, performing DC-AC conversion and transferring energy stored in the quasi-Z-source network to the load, generating an output AC voltage. In this state, the quasi-Z-source network does not boost the voltage; the inverter primarily performs its inversion function, converting DC power to AC output.

[0057] Assume that a cycle time is T, where the time in working and direct state is T0, and the time in non-direct state is T1. Figure 3 The equivalent circuit in the through state is:

[0058] u0=u L1 -u C2 ,u L2 =u C1 (1)

[0059] Depend on Figure 4 The equivalent circuit in the non-through state is:

[0060] u L2 =-u C2 ,u L1 =u0-u C1 (2)

[0061] The time T of one cycle, the non-through time T1, and the through time T0 satisfy the following relationship:

[0062] T1+T0=T (3)

[0063] According to the basic characteristics of the voltage across the inductor, the inductor L1 and the inductor L2 satisfy the voltage relationship:

[0064] u L1 T0+u L1 T1=0;u L2 T0+u L2 T1=0 (4)

[0065] According to (1)-(4), the voltage u applied to the inverter bridge can be obtained i The relationship with DC voltage u0 is:

[0066]

[0067] Inverter output phase voltage peak u amax for:

[0068]

[0069] In the above formula, u i The voltage applied to the inverter bridge is B, the boost factor is D, the shoot-through duty cycle is D = T0 / T, and M is the modulation index. As can be seen from the above formula, the voltage can be boosted by changing the shoot-through duty cycle and the modulation index.

[0070] In this embodiment, a quasi-Z source inverter and a high frequency transformer are set in each power router, such as Figure 5 The figure shows the topology of two interconnected power routers, with two high-frequency transformers in the center. Here, the low-voltage side is 100V, and the high-voltage side is 3kV / 1kHz. The quasi-Z-source inverter converts 100V DC into 200V / 1kHz high-frequency AC. This is then converted to 3kV AC via a high-frequency transformer with a transformation ratio of 1:15. Because energy flows in both directions, a symmetrical structure is used on the other side to convert 3kV AC into 100V DC.

[0071] Example 2

[0072] Based on the lunar research station microgrid system based on multi-source access power router proposed in Example 1, this embodiment proposes a control architecture of the microgrid system;

[0073] like Figure 6 As shown in the figure, the control architecture of the lunar microgrid system is divided into three layers:

[0074] 1) The lowest level is the energy router port converter module control strategy, including the low-voltage port control strategy for connecting various micro-sources and loads, and the high-voltage port control strategy for connecting to the high-voltage AC bus. The low-voltage port adopts a multi-mode control strategy, with photovoltaic, energy storage, fuel cell, and load access control modes. The high-voltage AC port converter functions to interconnect multiple energy routers, achieve the adaptation of low-voltage DC and high-voltage AC, and has two control modes: constant voltage control and constant power control. It also needs to be able to adaptively parallel multiple modules.

[0075] 2) The middle layer is the collaborative control layer for interconnecting multiple power routers, which needs to realize voltage stability control and power balance control after the interconnection of multiple power routers.

[0076] 3) The upper layer is the microgrid-level energy management control layer, which includes energy management algorithms based on power generation forecasting and load forecasting to improve the operating efficiency of the microgrid system.

[0077] Example 3

[0078] This example focuses on the simulation of multi-source module collaborative control at the power router layer, targeting the lunar research station microgrid system based on multi-source access to the power router proposed in Example 1. First, the hardware parameters and topology configuration of each simulation module and the power router are presented. Next, the simulation operating conditions and scenarios are introduced, including changes in photovoltaic irradiance, energy storage state of charge, and sudden load changes. Finally, the voltage, current, and power waveforms of key nodes are presented, and the simulation results are analyzed and verified.

[0079] (1) Hardware parameters and topology configuration

[0080] Table 1 lists the hardware parameters of the converter modules at each power router port and the main micro-sources used in the simulation. The main micro-sources include photovoltaic, energy storage, fuel cell, and small nuclear power modules. The photovoltaic, energy storage, and fuel cell components are configured with a nominal capacity of 2 kW; the small nuclear power module uses a 1 kW capacity. The load is primarily DC, with a rated DC voltage of 100 V and a maximum load of 2 kW.

[0081] Table 1 Simulation hardware parameters

[0082]

[0083] (2) Description of simulation conditions

[0084] To verify the effectiveness of the multi-source module collaborative control strategy, the following four typical operating conditions are constructed at the power router layer:

[0085] 1. Photovoltaic irradiance disturbance: simulated light intensity from 1000W / m 2 Dropped sharply to 800W / m 2, to test the system’s ability to respond to fluctuations in renewable energy output;

[0086] 2. Photovoltaic temperature disturbance: The ambient temperature of the photovoltaic modules was raised from 25°C to 75°C to examine the impact of photovoltaic characteristic degradation on the bus voltage under high temperature conditions.

[0087] 3. Fuel cell thermal disturbance: The fuel cell stack temperature is raised from 70°C to 90°C to evaluate the inhibitory effect of changes in electrochemical performance on output power.

[0088] 4. Load step change: Analyze the system power distribution and voltage recovery characteristics when the DC bus load suddenly increases from 1kW to 1.5kW and then continues to increase to 2kW.

[0089] Under the above operating conditions, the control mode switching of each port follows the multi-mode management strategy to ensure that the low-voltage port dynamically switches between photovoltaic, energy storage, fuel cells and load access, and the rated voltage of the DC side is stable at 100V.

[0090] (3) Simulation waveform and result analysis

[0091] The simulation results are as follows Figure 7 As shown, Figure 7 (a)-(f) represent the power waveforms of photovoltaics, fuel cells, small nuclear power, DC loads, energy storage batteries, and DC voltage under varying working conditions, respectively; they reflect the dynamic response characteristics of the system under different working conditions and verify the effectiveness of the proposed multi-source collaborative control strategy.

[0092] As can be seen, the output power of the photovoltaic modules decreases as light intensity decreases. This is because the reduced irradiance directly affects their photocurrent, which in turn reduces output power. To maintain system power balance, the energy storage module automatically enters a discharge state to compensate for the photovoltaic power shortfall. As the fuel cell's operating temperature increases, its electrochemical reaction rate and internal impedance change, resulting in a downward trend in output voltage and power. The system adjusts the energy storage output to smoothly compensate for fluctuations caused by fuel cell performance changes and ensure load-side voltage stability. The photovoltaic system also exhibits some output degradation as temperature rises, primarily due to the high temperature suppressing its open-circuit voltage. This further demonstrates the importance of a multi-source complementary mechanism under complex operating conditions. As a constant-power micro-source in the system, the small nuclear power system maintains a stable output power across all operating conditions, providing a baseline support for stable system operation. During multiple sudden load-side changes, the power gradually increased from 1kW to 2kW, triggering a dynamic system response. Constrained by power conservation, each micro-source automatically adjusts its output according to its control mode. Although the DC bus voltage experiences instantaneous fluctuations, it quickly recovers under the coordination of the control system. The system as a whole exhibits good voltage stability and dynamic adaptability.

[0093] The simulation results show that under various disturbance conditions, various micro-sources can achieve rapid and stable coordinated responses through the power router, effectively supporting the system's voltage stability and power balance, and verifying the practicality and robustness of the multi-source access control strategy.

[0094] Example 4

[0095] In this embodiment, the power transmission port of the introduced power router mainly realizes the energy conversion and control between the low-voltage DC side (100V) and the high-voltage AC side (3000V, 1kHz). This port adopts a quasi-Z-source converter (Z-Source Inverter, ZSI) combined with a high-frequency transformer topology to achieve voltage boosting and electrical isolation to meet the adaptation requirements between networks of different voltage levels. The system has two operating modes: constant voltage (VF) control and constant power (PQ) control. It supports adaptive parallel operation of multiple modules, adapts to different load requirements and network operation modes, and improves the flexibility and reliability of the system. Among them, the quasi-Z-source network expands the output voltage range of the traditional inverter through its unique boosting capability, effectively supporting the boosting of low-voltage DC input to high-voltage AC output. The high-frequency transformer realizes energy isolation and further voltage matching. The simulation parameter table of the two tests is shown in Table 2 below:

[0096] Table 2 Simulation parameters

[0097]

[0098] (1) VF control mode simulation verification

[0099] To verify the output voltage stability and dynamic response of the power router's transmission port under load disturbances in VF control mode, a 3kW resistive load was initially connected at 0s. At 0.3s, an additional 2kW resistive load was added, increasing the total load power to 5kW. A dual closed-loop control structure was employed: the outer loop, a voltage loop, ensured that the AC output voltage rapidly tracked the reference value; the inner loop, a current loop, ensured the system maintained good dynamic performance and robustness against load changes.

[0100] like Figure 8 The output line voltage is stable at around 4240V, corresponding to an effective line voltage of 3000V and a frequency of 1kHz. When an additional 2kW load is connected at 0.3s, the total load power increases to 5kW, and the output voltage drops slightly, then quickly recovers to a steady state with a recovery time of less than 10ms, indicating that the system has good voltage stability and dynamic response capabilities. Figure 9 The initial current shown is stable at the level corresponding to a 3kW load. When the load suddenly changes, the current amplitude increases accordingly and stabilizes quickly without obvious oscillation or instability. This verifies that the system has good load adaptability under the VF control strategy.

[0101] (2) PQ control mode simulation verification

[0102] To verify the active and reactive power control capabilities of the power router's transmission port under PQ control mode and its dynamic response to load disturbances, the initial commanded active power was set to 5kW and the commanded reactive power was set to 0kvar. At 0.3s, the active power command was stepped down from 5kW to 3kW, while the reactive power command remained unchanged at 0kvar. Based on the set PQ commands, the system adjusted the amplitude and phase of the AC output current through the active power loop and reactive power loop, respectively, to achieve accurate control of the output power.

[0103] like Figure 10 As shown in the figure, the output current amplitude decreases accordingly with the change of active power, and the waveform is stable without distortion, which further verifies the accuracy and load adaptability of the system under the PQ control mode. Figure 11 As shown in the figure, the red curve represents the change in active power, and the blue curve represents the change in reactive power. Initially, the system output active power stabilized at 5kW, and reactive power remained at 0kvar, meeting the set command. At 0.3s, the active power command was reduced to 3kW, and the system output power quickly tracked the set command. The actual output power transitioned quickly, with a fast recovery time. The power response was smooth, with no significant overshoot or oscillation, demonstrating excellent dynamic performance and stability in power control.

[0104] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0105] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.

Claims

1. The lunar research station microgrid system based on multi-source access power router is characterized by: include: Medium and large microgrids and multiple small microgrids. Medium and large microgrids use a high-voltage AC backbone network as the skeleton to connect various small microgrids. Each microgrid includes multiple power routers, which are connected in parallel through high-voltage AC ports. The power routers connect various distributed power sources through multiple ports, supply power to loads, and are responsible for the scheduling and management of multi-source energy. Each small microgrid configures micro sources and the ports and capacity of the power routers according to the load and in-situ resource characteristics of its power supply area.

2. The lunar research station microgrid system based on multi-source access power router according to claim 1 is characterized in that: Different ports of the power router are respectively connected to the load, energy storage module, fuel cell, water electrolysis hydrogen production module, nuclear power generation module and photovoltaic.

3. The lunar research station microgrid system based on multi-source access power router according to claim 2 is characterized in that: Small microgrids give priority to using photovoltaic power generation as the basic source of clean energy supply, directly supplying power to the load and charging the energy storage module when there is sufficient sunlight; when there is insufficient sunlight or the moon enters the night period, the nuclear power generation module and fuel cell serve as the main power supply modules; the water electrolysis hydrogen production module produces hydrogen and stores it for use in fuel cells when energy is abundant; the energy router can intelligently switch the power output path according to load demand, energy supply and energy storage status, and realize energy optimization distribution and power balance control.

4. The lunar research station microgrid system based on multi-source access power router according to claim 1 is characterized in that: The voltage of the high voltage alternating current is 3 kV and the frequency is 1 kHz.

5. According to the lunar research station microgrid system based on multi-source access power router according to claim 1, the port of the power router is a low-voltage DC power port with a voltage less than or equal to 100V; and all low-voltage DC power ports adopt a modular design and use the same topology.

6. The lunar research station microgrid system based on multi-source access power router according to claim 1 or 4, characterized in that: The power router is provided with a quasi-Z source inverter and a high-frequency transformer. The quasi-Z source inverter converts direct current into high-frequency alternating current, which is then converted into 3kV alternating current through the high-frequency transformer.

7. The lunar research station microgrid system based on multi-source access power router according to claim 6 is characterized in that: In the power router, the quasi-Z-source inverter converts DC power into 200V / 1kHz high-frequency AC power, and then obtains 3kV / 1kHz AC power through a high-frequency transformer with a transformation ratio of 1:

15.

8. The lunar research station microgrid system based on multi-source access power router according to claim 6 is characterized in that: The quasi-Z-source inverter includes an inverter bridge and a quasi-Z-source network located before the inverter bridge; the quasi-Z-source network includes two inductors L1 and L2 of the same size and two capacitors C1 and C2 of the same size.

9. The lunar research station microgrid system based on multi-source access power router according to claim 6 is characterized in that: The working state of the quasi-Z-source inverter is divided into a direct-through state and a non-direct-through state: In the direct-through state of the quasi-Z-source inverter, the switches of the inverter bridge are turned on at the same time, forming a short-circuit state, which is used for energy storage and conversion of the quasi-Z-source network, increasing the voltage of the DC bus and achieving voltage boosting; In the non-shoot-through state of the quasi-Z-source inverter, the switch tube operates according to the SPWM control strategy to perform DC-AC conversion, transfer the energy stored in the quasi-Z-source network to the load, and generate an output AC voltage.

10. A lunar research station equipped with the microgrid system according to any one of claims 1 to 9.

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