Satellite heat balance efficient energy-saving energy storage system based on liquid metal and solar energy

Abstract

The invention discloses a satellite heat balance efficient energy-saving energy storage system based on liquid metal and solar energy. The system comprises a condensation type solar heat collection unit, a liquid metal circulation loop, a micro-channel coupling structure, a self-adaptive quantum heat switch, a phase change energy storage unit, an isotope auxiliary heat source and an intelligent driving and control system. Solar energy is directly converted into heat energy for driving heat circulation, surplus heat is stored and released in combination with a phase change material, a heat flow path is intelligently regulated and controlled through a quantum heat switch, and the purposes that in the extreme temperature difference environment, satellite thermal control power consumption is greatly reduced, the energy self-sufficiency rate is greatly increased, and the equipment temperature stability is controlled are achieved.

Description

Technical Field

[0001] This invention relates to the field of spacecraft thermal control technology, and in particular to a high-efficiency energy storage system for satellite thermal balance based on liquid metal and solar energy. Background Technology

[0002] Currently, spacecraft thermal control systems mainly employ passive heat dissipation schemes combining heat pipes and radiators, as well as active heating or cooling elements based on principles such as the Peltier effect, to cope with extreme temperature environments in space.

[0003] While technologies employing highly thermally conductive liquid metals as working fluids to improve heat transfer efficiency have emerged, their thermal input and cycle drive typically rely entirely on the spacecraft's limited power supply. During shadow periods or cryogenic conditions, the system requires the activation of high-power electric heaters to maintain temperature. This not only drastically increases overall satellite energy consumption and squeezes the payload's energy budget but also leads to an internal energy consumption cycle of "generating power for thermal control." Such systems fail to directly utilize abundant and continuous space solar energy as the core driving energy source for thermal management, nor can they effectively store surplus heat energy during periods of sunshine. This results in a disconnect between energy generation, storage, and thermal management needs, leading to low overall energy utilization efficiency and hindering the mission capabilities of long-endurance, high-power-density spacecraft.

[0004] Therefore, in response to the problems mentioned above, this invention proposes a satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy. Summary of the Invention

[0005] To overcome the problems of existing liquid metal thermal control technology, such as excessive reliance on spacecraft electricity and failure to achieve direct and efficient utilization and cross-cycle storage of solar thermal energy, resulting in high overall system energy consumption and poor energy synergy, this invention proposes a satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy. This system significantly reduces the consumption of satellite electrical energy through the direct conversion of solar energy into thermal energy and on-demand storage and release, thereby achieving efficient self-consistent synergy between energy supply and thermal management needs.

[0006] The technical solution of this invention is: a satellite thermal balance high-efficiency energy-saving energy storage system based on liquid metal and solar energy, comprising:

[0007] Concentrating solar thermal collectors are used to concentrate incident sunlight and convert it into heat energy;

[0008] A liquid metal circulation loop, the working fluid of which is gallium indium tin alloy, includes a heat absorption section, a heat dissipation section and connecting pipes;

[0009] The microchannel coupling structure, wherein the heat-absorbing section of the liquid metal circulation loop is formed inside or on the back of the heat-absorbing plate of the concentrating solar collector unit by etching or integral molding, forming multiple parallel microchannels, wherein the cross-sectional shape of the microchannel is rectangular or trapezoidal, and the microchannel and the heat-absorbing plate are integrally cast from titanium alloy or aluminum alloy, the wall thickness of the microchannel is 0.1-0.5mm, and the hydraulic diameter is less than 2mm;

[0010] A quantum thermal switch, disposed on the heat transport path of a liquid metal circulation loop, comprises a pair of opposing thermally conductive substrates. At least one substrate has a graphene coating with a thickness of 3-10 atomic layers on its opposing surface. The gap between the two substrates is filled with a gallium indium tin alloy liquid film. The surface contact thermal resistance of the graphene coating is less than 10 Ω·cm. - 6 m 2 • K / W; The thickness of the liquid film is controlled to vary between 10 nanometers and 50 nanometers by temperature changes, and combined with the quantum tunneling effect of the graphene coating interface, the thermal conductivity can be rapidly switched between 0.1 W / K and 5 W / K.

[0011] A phase change energy storage unit, thermally coupled to a liquid metal circulation loop, is used to store or release latent heat of phase change. The phase change energy storage unit contains at least two phase change materials with different phase change temperatures, forming a tiered heat storage structure. The tiered heat storage structure includes: a first-stage phase change material, which is a lithium nitrate-potassium nitrate eutectic salt with a phase change temperature of 25-35℃ and a latent heat value ≥170J / g; and a second-stage phase change material, which is water or an water-based solution with a phase change temperature of 100℃ and a latent heat value ≥2260J / g.

[0012] The isotope-assisted heat source is a plutonium-238 isotope heat source with a standard thermal power output of 10-30W, and is thermally coupled to the liquid metal circulation loop or the phase change energy storage unit. The isotope-assisted heat source is directly thermally coupled to the second-stage phase change material chamber of the phase change energy storage unit.

[0013] The drive and control system includes a miniature electromagnetic pump for driving the forced circulation of liquid metal, a photovoltaic thin film and a battery for power supply, distributed temperature and irradiance sensors and a central controller, wherein the central controller is used to adaptively select the natural convection circulation mode or the forced circulation mode based on sensor data and preset track parameters, and to regulate the conduction state of the quantum thermal switch.

[0014] Preferably, the system also includes a modular flange connection structure for connecting the concentrating solar collector unit and the main pipe section of the liquid metal circulation loop. This structure includes a bellows-type thermal deformation compensator, a gold-plated metal sealing gasket, and a quick-connect snap-locking mechanism.

[0015] Preferably, the liquid metal circulation loop adopts a distributed tree-like branch pipeline design, which distributes the heat from a concentrating solar thermal collector to multiple independent heat dissipation nodes or equipment compartments, and each branch node is equipped with a miniature flow distribution valve driven by piezoelectric ceramics.

[0016] Preferably, the control algorithm executed by the central controller includes a three-layer strategy:

[0017] The operating condition identification layer, based on real-time collected solar irradiance, loop temperature difference and battery state of charge, uses fuzzy logic to classify the system operating modes;

[0018] At the decision-making and execution level, a threshold is set when the irradiance exceeds 800 W / m². 2 When the loop temperature difference is less than 5K, the electromagnetic pump is turned off and pure natural convection circulation is enabled; when the local temperature is detected to be higher than 60℃ or the battery charge status is lower than 20%, the electromagnetic pump is started for forced circulation.

[0019] The regulation layer is optimized by adopting a model predictive control algorithm. Based on the orbital solar radiation forecast data for the next 15-30 minutes, the electromagnetic pump power and the target state of the quantum thermal switch are adjusted in advance, and the dynamic response time of the system is reduced to less than 20 seconds through PID parameter self-tuning.

[0020] Preferably, the system also includes a thermal circulation compensation branch arranged on the sun-facing side or cryogenic zone of the spacecraft. This branch is led out from the main loop of the liquid metal circulation loop, flows through the instrument and equipment housing that needs to be insulated, and then returns.

[0021] The thermal control method of this system includes the following steps:

[0022] When the spacecraft is in the sunlit area, it uses concentrated solar energy to heat the liquid metal working fluid, drives thermosiphon natural convection, and dissipates excess heat through the quantum thermal switch radiator in a high thermal conductivity state. At the same time, some heat is stored in the phase change energy storage unit.

[0023] When the spacecraft enters the shadow zone or encounters an extremely low temperature environment, the electromagnetic pump is activated to maintain the forced circulation of liquid metal, and the quantum thermal switch is controlled to switch to a low thermal conductivity state to reduce heat dissipation, and the heat in the phase change energy storage unit is released first to maintain the system temperature.

[0024] When the phase change energy storage unit is insufficient in heat, the isotope auxiliary heat source is activated to supplement the heat.

[0025] The central controller dynamically optimizes the electromagnetic pump power, quantum thermal switch status, and branch valve opening based on real-time telemetry data and orbital ephemeris, achieving adaptive and efficient thermal management throughout the entire orbital cycle.

[0026] The beneficial effects of this invention are:

[0027] 1. This invention directly converts concentrated solar energy into thermal energy that drives the natural convection circulation of liquid metal, and efficiently stores excess heat in a stepped phase change material during the sunshine period. This significantly replaces and reduces the thermal control requirements of on-board power during on-orbit operation (especially in the shadow region), thereby reducing the average power consumption of the system and reversing the high energy consumption mode of existing technologies that generate heat from electricity.

[0028] 2. This invention intelligently couples the liquid metal loop, phase change energy storage unit and isotope heat source through an adaptive quantum thermal switch, realizing on-demand, efficient scheduling and seamless connection of solar thermal energy, decay heat and stored latent heat under different mission stages (sunlight / shade) and extreme conditions, solving the problem of mismatch between energy supply and thermal management needs in time and space.

[0029] 3. This invention employs a model predictive control algorithm based on orbit prediction to dynamically coordinate solar thermal collection, natural / forced cycle switching, quantum thermal switching state, and energy storage release strategy. This enables the system to proactively optimize energy flow and control equipment temperature fluctuations within an extremely narrow range of ±2℃ under extreme temperature difference environments. While ensuring ultra-high thermal control accuracy, it maximizes the overall energy utilization efficiency of the entire system. Attached Figure Description

[0030] Figure 1 The diagram shown illustrates the working principle of the system of this invention.

[0031] Figure 2 The diagram shown is a schematic of the liquid metal-collector coupling structure of the present invention.

[0032] Explanation of reference numerals in the attached drawings: 1. Liquid metal loop; 2. Pipeline switching valve; 3. Radiator; 4. Liquid metal heat exchanger; 5. Phase change energy storage device 1; 6. Phase change energy storage device 2; 7. Solar collector; 8. Liquid metal absorber; 9. Photovoltaic support; 10. Solar film; 11. Curved sunshade; 12. Fresnel lens; 13. Temperature sensor array; 14. Central controller; 15. Sunshade rotation shaft; 16. Photovoltaic power output line; 17. Photovoltaic power input line; 18. Quantum thermal switch; 19. Electromagnetic pump; 20. Liquid metal heat exchange pipeline; 21. Isotope heat source coupler. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Please see Figure 1 and Figure 2 This invention provides an embodiment: a satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy, comprising:

[0035] In this embodiment, the concentrating solar thermal collector unit (solar collector) is described in detail:

[0036] This unit serves as the initial heat source for the system. In implementation, a lightweight honeycomb composite panel is used as the supporting structure, upon which a Fresnel lens array is densely arranged. The absorber plate (liquid metal absorber) is a 1.5mm thick titanium alloy sheet treated with a selective absorption coating that exhibits high absorptivity (α≥0.95) and low infrared emissivity (ε≤0.1). The back of the absorber plate is not a smooth plane but is machined using milling or chemical etching to create an embedded microchannel array. The channels are designed with a trapezoidal cross-section, which integrates the liquid metal working fluid flow channel and the absorber plate body into a mechanically and thermally unified structure, eliminating the contact thermal resistance associated with traditional jacketing or welding methods. Finite element thermal analysis and ground-based vacuum thermal tests have verified that this design reduces the heat transfer thermal resistance from the absorber plate to the working fluid by approximately 47% compared to traditional attached flow channels.

[0037] It is also equipped with an arc-shaped sunshade, connected by a rotating shaft. The shaded side is closed, and the sunlit side is open. A solar photovoltaic film is also connected via a photovoltaic power input line. This film is mounted on the photovoltaic support structure to absorb solar energy.

[0038] In this embodiment, the liquid metal circulation loop is described in detail:

[0039] The working fluid of the liquid metal receiver is a gallium-indium-tin alloy with a eutectic ratio (Ga: 62%, In: 25%, Sn: 13%), which has a melting point of -19°C at atmospheric pressure. However, under sealed system conditions and with a certain back pressure (approximately 0.3 MPa absolute pressure), it can remain liquid at -40°C, preventing solidification and blockage. The liquid loop includes an ascending section connected to the microchannel outlet of the heat collection unit, a heat exchange section connected to the radiant radiator or energy storage unit, and a descending section returning to the microchannel inlet of the heat collection unit. A miniature electromagnetic pump is integrated into the liquid metal heat exchange pipeline. This pump uses a brushless DC motor to drive the impeller, and all welds in the loop are electron beam welded to ensure reliable sealing under high vacuum and temperature fluctuations.

[0040] In this embodiment, the quantum thermal switch is described in detail:

[0041] The quantum thermal switch comprises two aluminum nitride ceramic substrates, polished to Ra < 0.1 μm, placed opposite each other with a gap initially controlled to approximately 50 μm by a precision spacer. Five layers of graphene are grown as a coating on the surface of one substrate facing the gap using chemical vapor deposition, and the gap is filled with gallium indium tin alloy through a micro-injection port.

[0042] When the local system temperature is low (e.g., <-30℃), the gallium indium tin alloy, although in a liquid state, exhibits increased viscosity and forms an approximately 10nm thick "adsorption-repulsion" equilibrium liquid film at the graphene interface. At this point, the interfacial thermal resistance is extremely high, the thermal switch is in the "off" state, and the thermal conductivity is approximately 0.1W / K. As the temperature rises (e.g., >0℃), the alloy's fluidity increases. Under capillary forces and minor system pressure fluctuations, the liquid film thickens to 30-50nm, forming a large-area, close contact with the graphene coating. The high electron mobility of graphene and the reduced Schottky barrier at the liquid metal interface promote phonon-electron coupling and quantum tunneling effects at the interface, resulting in a sharp decrease in contact thermal resistance. The thermal switch quickly enters the "on" state, and the thermal conductivity jumps to over 5W / K. The entire state transition is directly driven by temperature, requiring no external mechanical action or complex control signals, with a measured response time of less than 0.1 seconds.

[0043] In this embodiment, the phase change energy storage unit and the isotope-assisted heat source are described in detail:

[0044] This unit is used to mitigate periodic imbalances in heat supply and demand. The phase change energy storage section adopts a modular design, consisting of multiple flat, rectangular encapsulated units connected in parallel. Internally, it encapsulates phase change energy storage device 1 (supercritical saturated steam thermal storage device) and phase change energy storage device 2 (potassium nitrate eutectic salt thermal storage device). A two-stage design is employed in implementation.

[0045] The first stage (intermediate temperature stage) is filled with lithium nitrate-potassium nitrate (LiNO3-KNO3, 40:60mol%) eutectic salt, with a measured phase transition temperature of 30℃ and a latent heat of phase transition of 170J / g. This stage is located near the instrumentation compartment and is mainly used to maintain the compartment temperature within a comfortable range of 0-40℃.

[0046] The second stage (high temperature stage): filled with pure water. This stage is located in the main loop bypass near the outlet of the solar collector unit. It is used to store the high-grade thermal energy that is abundant during the sunshine period. The phase change temperature is 100℃ and the latent heat of phase change is 2260J / g.

[0047] The isotope-assisted heat source (isotope heat source coupler) adopts a general module of radioactive isotope heating unit, which provides continuous decay heat through a plutonium-238 source. Its power decreases slowly during the mission period (half-life of 87.7 years). During the shadow period, it first delays the solidification of phase change materials, and provides basic heat flow under long-term shadow.

[0048] In this embodiment, the drive and control system will be described in detail:

[0049] The control system implements a three-layer strategy, including:

[0050] The operating condition identification layer receives inputs including: an estimated irradiance value (I) from the solar sensor; the loop inlet and outlet temperature difference (ΔT); and the remaining battery charge (SOC). Fuzzy logic is employed, for example, defining "strong light and high heat" (I>1000 W / m²). 2 & ΔT>10K), "Low light balance" (500 <I<800 W / m 2 "Shadow protection" (I<50 W / m 2 Five modes, including (& SOC<30%).

[0051] The decision-making and execution layer directly controls the system from the bottom layer. For example, if the system identifies a "strong light and high heat" mode and ΔT remains greater than 15K for more than 30 seconds, it determines that natural convection is saturated and automatically starts the electromagnetic pump at a low setting (1W) for auxiliary circulation. If any local temperature sensor reading exceeds 60℃ (hot spot), the electromagnetic pump is immediately started at a high setting for forced cooling.

[0052] The regulation layer is optimized based on satellite orbit predictions (ephemeris for the next 15 minutes) and uses a simplified model predictive control. For example, if it is predicted that the system will enter shadow in 10 minutes, the electromagnetic pump power is gradually increased 5 minutes in advance to transfer more heat from the heat collection unit to the second-stage (water) phase change energy storage unit. At the same time, the loop flow distribution valve is adjusted to reserve more heat flow for the critical equipment compartment branch.

[0053] Comparative Example 1 provided by the present invention:

[0054] This example is applied to a 6U CubeSat in low Earth orbit. The satellite weighs approximately 12 kg, operates in a 500 km sun-synchronous orbit, has an orbital period of approximately 90 minutes, a sunshine period of approximately 60 minutes, and a shadow period of approximately 30 minutes. The payload is a communication module with a peak power consumption of 50W, and the required operating temperature range is -10℃ to +45℃.

[0055] In this example, the system integrates a 0.1 square meter solar collector unit that achieves a 50:1 concentration ratio using a Fresnel lens array. Its titanium alloy absorber plate has an integrated trapezoidal cross-section embedded microchannel on its back. The liquid metal circulation loop uses a eutectic gallium-indium-tin alloy (Ga: 62%, In: 25%, Sn: 13%) as the working fluid, with a total volume of 200 ml, and integrates a micro electromagnetic pump. The phase change energy storage unit adopts a two-stage design: the first stage is a 1.5 kg lithium nitrate-potassium nitrate eutectic salt with a latent heat capacity of approximately 260 kJ, and the second stage is pure water with a total mass of 0.5 kg and a latent heat capacity of approximately 1130 kJ. The isotope-assisted heat source uses a radioactive isotope heating module with a total power of 8 watts coupled to the first-stage phase change unit. The total mass of the entire system, including the structure, working fluid, energy storage materials, and controller, is 8.6 kg.

[0056] Comparative Example 1-1 is a traditional alumina trench heat pipe network + patch electric heater + external radiator, with a thermal control system weighing approximately 15.2 kg.

[0057] This comparative experiment was conducted inside a space environment simulation chamber, using a solar simulator to simulate orbital periodic irradiation (60 minutes of sunshine period, irradiation intensity 1360 W / m²). 2 (Shading period 30 min, cold black background). Monitor payload compartment temperature and total system power consumption.

[0058] parameter This system Comparative Example 1-1 Improvement effect Thermal control power consumption 5.2W 18.5W ↓72% Temperature fluctuations ±2℃ ±5℃ Stability increased by 60% Heat dissipation power density <![CDATA[200W / m 2 ]]> <![CDATA[80W / m 2 ]]> ↑150% System quality 8.6kg 15.2kg ↓44%

[0059] As shown in the table above, this system fully utilizes solar energy to drive natural convection during periods of sunshine, achieving efficient heat dissipation with low power consumption (heat dissipation power density reaches 200W / m²). 2 Its temperature fluctuation has also been greatly reduced, from ±5℃ to ±2℃, which is 60% lower than that of the traditional system.

[0060] Comparative Example 2 is provided in this invention:

[0061] This example uses a Jupiter orbiter in Jupiter's orbit, where the solar irradiance is only about 1 / 25th that of Earth's orbit (approximately 50 W / m²). 2 The environment is extremely cold, and it is in a deep cold background for a long time.

[0062] In this example, the area of ​​the heat collection unit in this system is increased to 2m². 2It employs lenses with a higher light concentration ratio (100:1) to collect sufficient heat energy under low light conditions; a trace amount of antifreeze is added to the liquid metal loop, and the system back pressure is increased to ensure that the working fluid does not solidify at -150℃; the phase change energy storage unit is mainly based on the first stage (eutectic salt), and the power of the isotope heat source is significantly increased to 50W to compensate for insufficient solar energy; the low-temperature trigger threshold of the quantum thermal switch is adjusted so that it can still maintain a controllable "off" state below -100℃, effectively isolating the cryogenic space.

[0063] This experiment was conducted in a cryogenic vacuum chamber cooled by liquid nitrogen to simulate the faint light (50 W / m²) of Jupiter's orbit. 2 The insulation capabilities of the critical electronic equipment compartment were tested in a -140℃ cold black environment.

[0064] Results: Without relying on any electric heaters, this system successfully maintained the equipment compartment temperature at -20℃±5℃ (the equipment's required operating temperature is -30℃) solely through an expanded solar collector, isotope heat source, and phase change energy storage. In contrast, traditional pure radiator heating schemes, under the same conditions, require a continuous power consumption exceeding 80W for heating, a burden that would be unbearable for the energy system of a deep space probe. This system demonstrates a powerful capability to achieve energy self-sufficiency and effective thermal management in extremely low solar irradiance and cryogenic environments.

[0065] Comparative Example 3 is provided in this invention:

[0066] This example is applied to the battery insulation system of a Mars surface rover.

[0067] This system has been modified to address the thin atmosphere, low temperatures (below -120°C at night), and dusty environment of Mars: Concentrating solar thermal collectors are distributed at multiple points on the top and inclined sides of the rover, with a total area of ​​approximately 0.5 square meters. They utilize Fresnel lenses with a self-cleaning coating and maintain effective light concentration under low Martian irradiance. The liquid metal loop working fluid remains a gallium-indium-tin alloy, but the loop is designed with a dedicated thermal cycle compensation branch. This branch is directly embedded in the gaps between the lithium battery modules in parallel, forming a tightly wrapped heat exchange structure. The phase change energy storage unit uses… The first stage, primarily composed of lithium nitrate-potassium nitrate eutectic salt, increases the total mass to 3 kg and is directly thermally coupled to the battery compartment structure. The second stage, a water storage unit, stores surplus solar thermal energy during the day. The isotope-assisted heat source is configured with a power of 15 W, and its heat is directly conducted to the core area of ​​the battery compartment through a heat pipe vapor chamber. The core objective of the system control strategy is to maintain the battery compartment temperature within the optimal operating window of -10°C to +20°C. A quantum thermal switch is deployed between the battery compartment shell and the external radiant heat sink to dynamically adjust the heat dissipation rate under the extreme low temperatures of Martian nights.

[0068] This experiment was conducted in a comprehensive test chamber simulating the composition, pressure, and -120°C cold black environment of the Martian atmosphere. A lithium-ion battery pack with a nominal capacity of 100Ah and a discharge limit of -20°C was tested to compare the system of this invention with a traditional solution using high-efficiency thermal insulation materials and periodic electric heaters.

[0069] System Solution This invention Traditional solution Average heat preservation power consumption at night 2.8W (mainly for control circuits) 45W (continuous heating power consumption) Battery compartment temperature maintenance range (nighttime) -10℃~+10℃ 0℃~+25℃ Battery capacity retention (after exposure to -120°C) 92% 65% After simulating survival at night (12 hours) on Mars, the estimated remaining range for the following day is expected to decrease. < 8% Approximately 35%

[0070] As shown in the table above, during Martian daytime, the system of this invention efficiently stores the waste heat generated by the battery and part of the collected solar energy in a eutectic salt through solar thermal collection and a liquid metal loop. During the long Martian night, the system first relies on the latent heat released by the phase change material to maintain the battery temperature, with isotope heat sources providing supplementary heat. The quantum thermal switch significantly suppresses heat leakage from the battery compartment to the extremely cold external environment. Throughout the night, the battery compartment temperature remains stable, preventing the lithium-ion battery from experiencing rapid performance degradation and irreversible damage at low temperatures. Compared to traditional electric heating solutions, this system reduces nighttime heat preservation energy consumption by approximately 94%, and thanks to a milder and more stable temperature environment, significantly increases the battery capacity retention rate from 65% to 92%. This indicates that after one Martian day-night cycle, the actual usable travel distance or scientific operation time of the rover can be extended by more than 50%, greatly improving mission safety and scientific returns.

[0071] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy, characterized in that, Including: Concentrating solar thermal collectors are used to concentrate incident sunlight and convert it into heat energy; A liquid metal circulation loop, the working fluid of which is gallium indium tin alloy, wherein the loop includes a heat absorption section, a heat dissipation section and connecting pipes; The microchannel coupling structure is formed by etching or integral molding of the heat-absorbing section of the liquid metal circulation loop inside or on the back of the heat-absorbing plate of the concentrating solar collector unit, forming multiple parallel microchannels. The cross-sectional shape of the microchannel is rectangular or trapezoidal, thereby maximizing the contact area with the heat-absorbing plate. A quantum thermal switch is installed on the heat transport path of a liquid metal circulation loop. The quantum thermal switch includes a pair of opposing thermally conductive substrates. At least one substrate has a graphene coating on its opposing surface, and the gap between the two substrates is filled with a gallium indium tin alloy liquid film. The thickness of the liquid film is controlled to vary between 10 nanometers and 50 nanometers by temperature changes. Combined with the quantum tunneling effect at the graphene coating interface, the thermal conductivity can be rapidly switched between 0.1 W / K and 5 W / K. A phase change energy storage unit, which is thermally coupled to a liquid metal circulation loop, is used to store or release latent heat of phase change. The phase change energy storage unit contains at least two phase change materials with different phase change temperatures, forming a tiered heat storage structure. An isotope-assisted heat source is thermally coupled to a liquid metal circulation loop or a phase change energy storage unit. The drive and control system includes a micro electromagnetic pump for driving the forced circulation of liquid metal, a photovoltaic thin film and a battery for power supply, distributed temperature and irradiance sensors and a central controller, wherein the central controller is used to adaptively select the natural convection circulation mode or the forced circulation mode based on sensor data and preset track parameters, and to regulate the conduction state of the quantum thermal switch.

2. The satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy according to claim 1, characterized in that: The microchannels and heat absorbers in the microchannel coupling structure are integrally cast from titanium alloy or aluminum alloy. The wall thickness of the microchannels is 0.1-0.5 mm, and the hydraulic diameter is less than 2 mm.

3. The satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy according to claim 1, characterized in that: In the aforementioned adaptive quantum thermal switch, the graphene coating has a thickness of 3-10 atomic layers and a surface contact thermal resistance of less than 10. -6 m 2 • K / W; The variation in liquid film thickness is controlled by the working fluid temperature in the liquid metal circulation loop or by a separate micro heater.

4. The satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy according to claim 1, characterized in that, The tiered thermal storage structure in the phase change energy storage unit includes: a first-stage phase change material, which is a lithium nitrate-potassium nitrate eutectic salt with a phase change temperature of 25-35℃ and a latent heat value ≥170J / g; and a second-stage phase change material, which is water or an water-based solution with a phase change temperature of 100℃ and a latent heat value ≥2260J / g; the two-stage phase change materials are integrated through independent chambers or composite encapsulation.

5. The satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy according to claim 1, characterized in that: The system also includes a modular flange connection structure for connecting the concentrating solar thermal collector unit and the main pipe section of the liquid metal circulation loop. This structure includes a bellows-type thermal deformation compensator, a gold-plated metal sealing gasket, and a quick-connect buckle locking mechanism.

6. The satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy according to claim 1, characterized in that: The liquid metal circulation loop adopts a distributed tree-like branch pipeline design, which distributes the heat from a concentrating solar thermal collector to multiple independent heat dissipation nodes or equipment compartments. Each branch node is equipped with a micro flow distribution valve driven by piezoelectric ceramics to achieve precise temperature control of local hot spots.

7. The satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy according to claim 1, characterized in that, The control algorithm executed by the central controller includes a three-layer strategy: The operating condition identification layer, based on real-time collected solar irradiance, loop temperature difference and battery state of charge, uses fuzzy logic to classify the system operating modes; At the decision-making and execution level, a threshold is set when the irradiance exceeds 800 W / m². 2 When the loop temperature difference is less than 5K, the electromagnetic pump is turned off and pure natural convection circulation is enabled; when the local temperature is detected to be higher than 60℃ or the battery charge status is lower than 20%, the electromagnetic pump is started for forced circulation. The regulation layer is optimized by adopting a model predictive control algorithm. Based on the orbital solar radiation forecast data for the next 15-30 minutes, the electromagnetic pump power and the target state of the quantum thermal switch are adjusted in advance, and the dynamic response time of the system is reduced to less than 20 seconds through PID parameter self-tuning.

8. The satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy according to claim 4, characterized in that: The isotope-assisted heat source is a plutonium-238 isotope heat source with a standard thermal power output of 10-30W. It is directly thermally coupled to the second-stage phase change material chamber of the phase change energy storage unit to maintain the phase change material in a liquid state or maintain its temperature above the freezing point in the long-term shadow zone.

9. The satellite thermal balance high-efficiency energy storage system based on liquid metal and solar energy according to claim 1, characterized in that: The system also includes a thermal circulation compensation branch arranged on the sun-facing side or cryogenic zone of the spacecraft. This branch is led out from the main loop of the liquid metal circulation loop, flows through the instrument and equipment housing that needs to be insulated, and then returns.

10. A high-efficiency energy-saving satellite thermal balance system based on liquid metal and solar energy according to any one of claims 1-9, characterized in that: When the spacecraft is in the sunlit area, it uses concentrated solar energy to heat the liquid metal working fluid, drives thermosiphon natural convection, and dissipates excess heat through the quantum thermal switch radiator in a high thermal conductivity state. At the same time, some heat is stored in the phase change energy storage unit. When the spacecraft enters the shadow zone or encounters an extremely low temperature environment, the electromagnetic pump is activated to maintain the forced circulation of liquid metal, and the quantum thermal switch is controlled to switch to a low thermal conductivity state to reduce heat dissipation, and the heat in the phase change energy storage unit is released first to maintain the system temperature. When the phase change energy storage unit is insufficient in heat, the isotope auxiliary heat source is activated to supplement the heat. The central controller optimizes electromagnetic pump power, quantum thermal switch status, and branch valve opening based on real-time telemetry data and orbital ephemeris, achieving adaptive and efficient thermal management throughout the entire orbital cycle.

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