Modular nuclear reactor power plant

Abstract

The application discloses a modular nuclear reactor power supply device, which comprises one or more power output subsystem cabin sections; the power output subsystem cabin section comprises a cabin shell, a final heat sink, a power adapter device, and a reactor, a helium-xenon thermoelectric conversion loop and a shadow shielding structure arranged in the cabin shell; a coolant channel is formed in the reactor, the coolant channel is filled with a helium-xenon mixed gas, the helium-xenon mixed gas is circulated in the helium-xenon thermoelectric conversion loop to export the heat of the reactor core and generate electric energy; the power adapter device converts the electric energy output by the helium-xenon thermoelectric conversion loop into a desired voltage value matched with a load end and then exports the electric energy to the load end; the power adapter device is connected with multiple power output subsystem cabin sections to realize power output in a parallel mode. Compared with the existing problems of insufficient chemical energy, solar energy and decay energy, the application can generate heat energy through a continuous chain fission reaction and realize continuous supply of electric energy through a thermoelectric conversion loop, and the energy density is high.

Description

Technical Field

[0001] This application relates to the field of reactor technology, and more particularly to a small fission reactor power supply device for powering space stations, deep space shuttle propulsion for traveling to and from Mars or other asteroids, and support for star surface bases. Background Technology

[0002] Currently, the primary energy sources for human space activities are chemical energy (the combustion of chemical fuels), solar energy, and the decay energy of radioactive isotopes (such as nuclear batteries). Chemical energy is the main energy form relied upon by rocket engines, with the advantage of high thrust, making it the preferred energy form for spacecraft to overcome Earth's gravity and enter space orbit. However, its disadvantages include low specific impulse, requiring a large amount of fuel to achieve a unit propulsion effect, resulting in low fuel utilization efficiency. While solar energy does not consume fuel, it is easily obscured, leading to intermittent power supply. Nuclear decay batteries can provide stable power, but their power density is low, which cannot meet the high energy requirements of propulsion for large spacecraft and support for space bases.

[0003] Space nuclear power technology based on fission nuclear reactors is a realistic and viable technology that can break through the development limits of traditional space power technology and is one of the disruptive technologies that will change the future landscape of aerospace power.

[0004] Future exploration and development projects on the Moon, Mars, and asteroids place higher demands on spacecraft propulsion capabilities and mission self-sufficiency. Different types of space missions have varying energy requirements. For example, a Mars mission requires nuclear propulsion systems with power levels of 1 MWe to 5 MWe for payload transport between Earth and Mars. If used as a power source for an orbital space station, a 1 MWth reactor nuclear power source can generally meet the needs. If used to support a planetary base, a reactor power source with a power level of over 1 MWe is required, and this needs to be expanded according to mission requirements. Therefore, to adapt to the different energy requirements of space missions, a new technological solution is urgently needed. Summary of the Invention

[0005] This application provides a modular nuclear reactor power supply device to solve the problem of insufficient energy for space missions based on chemical energy, solar energy and decay energy in the prior art.

[0006] To achieve the above objectives, this application provides the following technical solution:

[0007] This application provides a modular nuclear reactor power supply device, including one or more power output subsystem modules. Each power output subsystem module includes a module outer shell, a final heat sink disposed outside the module outer shell, a power adapter device disposed at one end of the module outer shell, and a reactor, a helium-xenon thermoelectric conversion loop, and a shadow shielding structure disposed within the module outer shell. The shadow shielding structure is used to shield the reactor core from radiation. A coolant channel is formed within the reactor, and a helium-xenon mixed gas is introduced into the coolant channel. The helium-xenon mixed gas circulates in the helium-xenon thermoelectric conversion loop to remove heat from the reactor core and generate electrical energy. The power adapter device is connected to the helium-xenon thermoelectric conversion loop to convert the electrical energy output from the helium-xenon thermoelectric conversion loop into a desired voltage value adapted to the load and then output it to the load. The power adapter device is connected to multiple power output subsystem modules in parallel to achieve power output.

[0008] Furthermore, in the above technical solution, the outer shell of the compartment is an aluminum alloy shell with graphite coated on its outer surface, or a titanium alloy shell with graphite coated on its outer surface.

[0009] Furthermore, two docking mechanisms are arranged opposite each other on the outer shell of the compartment, and two adjacent power output subsystem compartments are assembled through the docking mechanisms.

[0010] Furthermore, the reactor is a fast neutron reactor; the reactor core includes a central control rod, and an inner fuel assembly, an outer fuel assembly, and a reflector layer that are sequentially surrounded by the central control rod; several control drums are distributed in a ring shape within the reflector layer; several coolant channels are formed between the outer fuel assembly and the reflector layer.

[0011] Furthermore, the inner fuel assembly and the outer fuel assembly are respectively columnar fuel assemblies with a hexagonal cross-section, and the fuel in the columnar fuel assembly is UO2 with a U-235 enrichment of less than 20w.

[0012] Furthermore, the shadow shielding structure is provided around the reactor.

[0013] Furthermore, the shadow shielding structure is a frustum-shaped shell structure; the sidewall of the shell structure includes three radiation shielding layers, namely: a light component shielding layer, a heavy component shielding layer, and a thermal shielding layer; the light component shielding layer is used to reduce neutron flux, the heavy component shielding layer is used to reduce gamma radiation, and the thermal shielding layer is used to reduce radiative heat.

[0014] Furthermore, the light component shielding layer is made of lithium hydride; the heavy component shielding layer is made of tungsten; and the heat shielding layer is made of boron-containing stainless steel.

[0015] Furthermore, the coolant channel is connected to the helium-xenon thermoelectric conversion circuit; the helium-xenon thermoelectric conversion circuit includes several gas transmission pipelines, and a compressor, a regenerator, a turbine, and a cooler connected through the gas transmission pipelines; the gas output from the coolant channel is compressed and pressurized by the compressor, enters the regenerator for preheating, and then enters the reactor core for heating. The heated gas enters the turbine for expansion and work, then enters the regenerator to release waste heat, then enters the cooler for cooling, and finally flows back to the compressor to form a helium-xenon mixed gas cycle; the waste heat of the cooler is discharged through a radiant radiator.

[0016] Furthermore, the radiant radiator includes multiple radiant radiator units, each equipped with heat pipes and radiant fins, and a heat insulation layer installed at the bottom of the radiant fins. When the flowing helium-xenon mixed gas absorbs waste heat discharged from the heat source through the helium-xenon thermoelectric conversion circuit as a medium, the heat is transferred to the radiant radiator as it flows through it. The heat is then transferred to the radiant fins via the heat pipes, and the heat insulation layer shields the spacecraft from radiation. The heat is then discharged into space through radiation.

[0017] Furthermore, the power adapter is a voltage conversion device, which is connected to multiple power output subsystem modules and forms a parallel connection with the multiple power output subsystem modules, and outputs the power of the electrical energy generated by the multiple power output subsystem modules in a parallel manner.

[0018] Furthermore, the power output subsystem section outputs electrical energy to the load end through the power adapter; the load end is a power-consuming unit, which includes a payload section and an electric propulsion device.

[0019] Furthermore, the power adapter is provided with a connection mechanism, which is adapted to connect to the load end.

[0020] Furthermore, the electric propulsion device includes several electric propulsion subsystems, and several electric output subsystem sections supply power to the electric propulsion subsystems through electric adapters on them.

[0021] Furthermore, when the modular nuclear reactor power supply device provides power for deep space shuttle propulsion, both the payload compartment and the electric propulsion device are placed behind the shadow shielding structure of the electric output subsystem compartment; the electric output subsystem compartment and the electric propulsion device are arranged opposite each other at both ends of the payload compartment.

[0022] Compared with the prior art, this application has the following advantages:

[0023] 1. This application provides a modular nuclear reactor power supply device, which consists of multiple power output subsystem modules. Each power output subsystem module includes a module shell, a final heat sink located outside the module shell, a power adapter located at one end of the module shell, and a reactor, a helium-xenon thermoelectric conversion loop, and a shadow shielding structure located inside the module shell. The helium-xenon thermoelectric conversion loop can export the core heat and convert it into electrical energy, realizing the physical conversion process of nuclear fission reaction heat into electrical energy. The electrical energy obtained after conversion is converted into a desired voltage value adapted to the load end by the power adapter and exported to the load end. The power adapter is connected to multiple power output subsystem modules to realize power output in parallel. Therefore, the nuclear reactor power supply device provided in this application achieves modular configuration of multiple power output subsystem modules through a power adaptation device. Different power output levels are selected for different missions, and one or more power output subsystem modules can be selected to participate in the mission. This results in higher overall reliability and greater tolerance for module failure. Compared with the energy shortage problem of space missions based on chemical energy, solar energy, and decay energy in the prior art, the nuclear reactor power supply scheme adopted in this application can generate heat energy through a continuous chain fission reaction and achieve power supply through a coupled thermoelectric conversion circuit, thereby driving the electric propulsion device to generate thrust. It has the characteristics of high energy density, low fuel consumption, high output power, long working life, high self-regulation capability, and strong environmental adaptability. Based on these characteristics, the space nuclear reactor power supply is the most ideal energy source for long-term, high-power space applications such as deep space exploration, cargo spacecraft propulsion, and star surface base support.

[0024] 2. The modular nuclear reactor power supply device provided in this application is a small space nuclear power device with the functions of powering space stations, deep space shuttle propulsion for traveling to and from Mars or other asteroids, and supporting star surface bases. As a device that converts the thermal energy generated by the nuclear reactor into electrical energy in space missions, a single device contains several power output subsystem modules, and each module can be combined to provide different power outputs for different missions.

[0025] 3. The modular design of several power output subsystems of the modular nuclear reactor power supply device provided in this application allows for a large design margin in the power supply design scheme, enabling the adoption of a large redundancy design to ensure the safety of the system. Furthermore, it has a higher tolerance for module failure and high system reliability. In addition, the modular design shortens the research cycle and reduces the testing cost. Only the complete research and testing of the modules are required to ensure the performance of the combined system.

[0026] 4. The power output subsystem module provided in this application has a shadow shielding structure installed in its module structure. The shadow shielding structure can provide radiation shielding for all power output subsystem modules, thereby protecting each payload module located at one end of the power output subsystem module from radiation hazards from the nuclear reactor power supply device. The shadow shielding structure is located between the reactor body and other power supply systems as well as the spacecraft payload, and can reduce the radiation dose generated by the nuclear reactor to a level acceptable to the payload or astronauts.

[0027] 5. Because the nuclear reactor power supply unit provided in this application adopts a modular design, each module can achieve the overall power output of the unit by being connected in parallel with other power output subsystem modules. This design can effectively reduce the system complexity and construction cost of the nuclear power conversion facilities within a single module, improve the system reliability of the nuclear reactor power supply unit as a whole, and improve the overall mission reliability and system economy of the deep space shuttle spacecraft. Also thanks to the modular design, the modules can be mass-produced and customized for on-orbit assembly according to different mission requirements, thereby significantly reducing the design cost and preparation cycle of space missions and improving the reliability of the propulsion system.

[0028] 6. The modular nuclear reactor power supply device provided in this application can be configured with different power outputs through different numbers of power output subsystem modules, which makes it easy for the nuclear reactor power supply device to be configured with different modules to provide different power to propel the deep space shuttle spacecraft forward according to the different mission requirements of the spacecraft. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing this application. For example, based on the technical concepts disclosed in this application and the exemplary drawings, those skilled in the art are able to easily make conventional adjustments or further optimizations to the addition / reduction / classification, specific shapes, positional relationships, connection methods, and size ratios of certain units (components).

[0030] Figure 1 This is a top view of a modular nuclear reactor power supply device provided in this application in one embodiment, illustrating three power output subsystem modules, but in practice it may include more power output subsystem modules.

[0031] Figure 2This is a schematic diagram of the main structure of a modular nuclear reactor power supply device provided in this application in one embodiment, showing three power output subsystem modules, but in reality, it may include more power output subsystem modules.

[0032] Figure 3 This is a top view of a power output subsystem section of a modular nuclear reactor power supply device provided in this application, as one embodiment.

[0033] Figure 4 This is a top view schematic diagram of a modular nuclear reactor power supply device provided in this application in one embodiment, and... Figure 1 In contrast, this diagram shows a schematic of the connection between the pipe section of the helium-xenon thermoelectric conversion circuit and the radiant heat sink;

[0034] Figure 5 This is a schematic diagram of a space heat pipe radiative cooling system for a modular nuclear reactor power supply device provided in this application, in one embodiment.

[0035] Figure 6 This is a schematic diagram of the system principle of the helium-xenon thermoelectric conversion circuit of the modular nuclear reactor power supply device provided in this application in one embodiment;

[0036] Figure 7 This is a schematic diagram illustrating the application principle of the modular nuclear reactor power supply device provided in this application in a deep space shuttle spacecraft in one embodiment.

[0037] Figure 8 This is a schematic diagram showing the installation positions of the payload compartment, electric propulsion device, shadow shielding structure, and power output subsystem compartment in one embodiment of the application of the modular nuclear reactor power supply device provided in this application in a deep space shuttle spacecraft for deep space shuttle propulsion.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1. Power output subsystem section; 2. Section shell; 3. Docking mechanism; 4. Power adapter; 5. Connection mechanism; 6. Reactor; 7. Helium-xenon thermoelectric conversion circuit; 8. Shadow shielding structure; 9. Compressor; 10. Regenerator; 11. Steam turbine; 12. Cooler; 13. Generator; 14. Radiant radiator; 15. Heat pipe; 16. Radiant fins; 17. Heat exchanger; 18. Circulating fluid pump; 19. Payload section; 20. Electric propulsion system. Detailed Implementation

[0040] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] In the description of this application: unless otherwise stated, "a plurality of" means two or more. The terms "first," "second," "third," etc., in this application are intended to distinguish the objects referred to and do not have any special meaning in terms of technical connotation (e.g., they should not be construed as an emphasis on importance or order). Expressions such as "including," "comprising," and "having" also mean "not limited to" (certain units, components, materials, steps, etc.).

[0042] The terms used in this application, such as "upper," "lower," "left," "right," and "middle," are generally used to facilitate intuitive understanding by referring to the accompanying drawings, and are not absolute limitations on the positional relationships in the actual product. Changes in these relative positional relationships, without departing from the technical concept disclosed in this application, should also be considered within the scope of this application.

[0043] Example

[0044] To address the energy shortage problem in existing space missions based on chemical energy, solar energy, and decay energy, this application provides a modular nuclear reactor power supply device, i.e., a small-scale space nuclear power device, capable of powering space stations, propelling deep space shuttles to and from Mars or other asteroids, and supporting planetary bases. The modular nuclear reactor power supply device provided in this application is a device that converts the thermal energy generated by a nuclear reactor into electrical energy during space missions. A single device comprises several power output subsystem modules, which can be combined to provide different power outputs for different missions.

[0045] The nuclear reactor power propulsion scheme provided in this application can generate heat energy through a continuous chain fission reaction and supply electrical energy through a coupled thermoelectric conversion system, thereby driving an electric propulsion device to generate thrust. This technical solution features high energy density, low fuel consumption, high output power, long service life, high self-regulation capability, and strong environmental adaptability. Based on these characteristics, space nuclear reactor power is the most ideal energy source for long-term, high-power space applications such as deep space exploration, cargo spacecraft propulsion, and space station support.

[0046] The structure of the modular nuclear reactor power supply device provided in this application is described in detail below:

[0047] This application provides a modular nuclear reactor power supply device, which is implemented using a modular design and includes one or more power output subsystem modules 1 (hereinafter referred to as "modules"). Each power output subsystem module 1 contains a complete physical process of "converting nuclear energy into electrical energy" (a chain fission reaction generates heat energy, which is then coupled to a thermoelectric conversion system to supply electrical energy, i.e., a helium-xenon thermoelectric conversion loop 7, or a nuclear power conversion device), capable of independently outputting 1 MWth of thermal power (approximately 400 kWe of electrical power). Different modules are connected in parallel to achieve overall power output; the modules are electrically connected to the electric propulsion subsystem. Each module is launched into space by a conventional energy (chemical fuel) rocket, and the functional systems are assembled in orbit in low Earth orbit. The megawatt-class nuclear energy module can not only perform deep space transportation missions but also space station power supply and planetary base support missions.

[0048] Further, see Figures 1 to 3 The power output subsystem module includes a module outer shell 2, a final heat sink located outside the module outer shell 2, a power adapter 4 located at one end of the module outer shell 2, and a reactor 6, a helium-xenon thermoelectric conversion loop 7, and a shadow shielding structure 8 located inside the module outer shell 2. The shadow shielding structure 8 shields the reactor core of the reactor 6 from radiation. Coolant channels are formed within the reactor 6, through which a helium-xenon gas mixture circulates, removing heat from the reactor core and generating electricity within the helium-xenon thermoelectric conversion loop 7. The power adapter 4 is connected to the helium-xenon thermoelectric conversion loop 7 to convert the electrical energy output from the loop into a desired voltage value adapted to the load before outputting it to the load. The power adapter 4 is connected to multiple power output subsystem modules 1 in parallel to achieve power output. The power adapter 4 is a voltage conversion device that converts electricity into a desired value, enabling it to appropriately drive the electrical load.

[0049] In one embodiment, the power adapter 4 may include various units such as semiconductor units, capacitor units, and silicon controlled rectifier (SCR) devices. The semiconductor units and SCRs include various switching elements, which are units capable of converting power, for example, from direct current to alternating current by controlling the timing of current flow.

[0050] In one embodiment, the nuclear reactor power supply device provided in this application may consist of 1 to 5 power output subsystem modules 1. The nuclear reactor power supply device provided in this application adopts a modular design, selecting different power output levels for different tasks, and then selecting one or more modules to participate in the task. Each module can achieve power output through a nuclear power conversion module. The power output is transmitted to the electric propulsion subsystem or other electrical loads through an organic connection structure between the modules. The organic connection structure between the modules is implemented by a power adapter 4, which is connected to each power output subsystem module 1, and outputs the electrical power of each power output subsystem module 1 in parallel.

[0051] The nuclear reactor power supply device obtained by the modular design in this application has the following advantages:

[0052] 1. Ample design margin: Due to the low radiation dose and structural mass of the system, a large redundancy design can be adopted to ensure the safety of the system;

[0053] 2. High system reliability: The high-power output structure achieved by combining multiple small propulsion modules in parallel has a higher tolerance for module failure;

[0054] 3. Lower temperature requirements for materials: Due to the reduced thermal efficiency requirements of a single reactor, the outlet temperature is relatively low. The requirements for reactor structural materials and component materials are comparable to those of existing engineering systems, providing a better foundation for safety design.

[0055] 4. The research cycle is short and the testing cost is low. Only the complete research and testing of the modules are required to ensure the performance of the combined system.

[0056] Since the power output provided in this application is transmitted to the electric propulsion subsystem through the organic connection structure between the modules, safety-related issues should be considered during space docking: first, the method of avoiding collisions; and second, the method of preventing reactor radiation and space particle radiation.

[0057] For safety reasons, the power output subsystem module 1 provided in this application incorporates a shadow shielding structure within its module structure. This shadow shielding structure provides radiation shielding for all power output subsystem modules 1, thereby protecting the various payload modules located at one end of power output subsystem module 1 from radiation hazards from the nuclear reactor 6 power supply unit. The shadow shielding structure 8 is located between the reactor body, other power systems, and the spacecraft payload, and can reduce the radiation dose generated by the nuclear reactor to a level acceptable to the payload or astronauts.

[0058] In one embodiment, the shadow shielding structure is a frustum-shaped shell structure, and the apex angle of the frustum can be in the range of 14° to 17°. Of course, this angle can be adjusted appropriately according to the actual shielding requirements.

[0059] In one embodiment, the outer shell of the shadow shielding structure is a radiation shielding layer, which is a multi-layered structure composed of various materials with different functions. The shielding materials can be divided into three types: first, a light component shielding layer that reduces neutron flux; second, a heavy component shielding layer that reduces gamma radiation; and third, a thermal shielding layer used to reduce radiative heat release within the shielding layer. This thermal shielding layer is used in high-radiation-field radiation shielding of reactors operating in areas with strong radiation fields and high heat loads.

[0060] In the shadow shielding structure provided in this application, the radiation shielding layer consists of three shielding layers: a thermal shielding layer, a light component shielding layer, and a heavy component shielding layer. Specifically: the thermal shielding layer is made of boron-containing stainless steel and serves to shield heat and neutrons; the light component shielding layer is made of lithium hydride (LiH) to shield neutrons, and to prevent lithium hydride deliquescence and hydrogen leakage, the lithium hydride is encapsulated in a container made of stainless steel or titanium alloy; the heavy component shielding layer is made of tungsten material to shield gamma rays.

[0061] In one embodiment, the three shielding layers constituting the radiation shielding layer can be arranged in the following order: from the core to the farthest point, the shielding layers are: thermal shielding layer, heavy component shielding layer, and light component shielding layer.

[0062] In one embodiment, several nuclear reactor power output subsystem sections 1 include multiple power conversion mechanisms that internally contain a complete physical process of "converting nuclear energy into electrical energy," namely, a helium-xenon thermoelectric conversion loop 7. The nuclear reactor 6, serving as the power source, is a fast neutron reactor. The reactor core of reactor 6 consists of columnar fuel assemblies with a hexagonal cross-section. The fuel is in the form of UO2, with a U-235 enrichment of less than 20 wt%. A control drum surrounds the core, and the outermost layer is a radiation shielding layer. The core is cooled by helium-xenon gas; new heat is carried away by the coolant and generated through the helium-xenon thermoelectric conversion loop 7 (a regenerative closed Brayton cycle system using a mixture of helium and xenon as the medium).

[0063] In one embodiment, see Figure 6 The principle of the aforementioned regenerative closed Brayton cycle system is as follows: the working medium (propellant) is pressurized in compressor 9, preheated in regenerator 10, and then heated in the reactor core. After heating, the working medium enters the turbine to expand and perform work, then enters regenerator 10 to release waste heat, then enters cooler 12 to cool, and finally enters compressor 9 to complete the closed cycle. Turbine 11 and compressor 9 are respectively connected to generator 13. Waste heat from cooler 12 is discharged into the environment through radiant radiator 14.

[0064] The nuclear reactor power supply device provided in this application has the following two advantages in using a helium-xenon mixture as the cooling medium: First, the operating temperature of the helium-xenon cycle can exceed 1300 degrees Celsius, which can significantly improve the overall thermal efficiency of the system; Second, the operating pressure of the helium-xenon cycle is about 7 MPa, which is relatively low among existing gaseous coolants. High operating pressure will result in thicker equipment walls, greater system weight, and a greater risk of leakage.

[0065] See Figure 5 The aforementioned radiant radiator 14 is a heat pipe type space radiant radiator. The heat pipe type space radiant radiator consists of multiple heat pipe type radiant radiator units. Its working process is as follows: the flowing coolant absorbs the waste heat after thermoelectric conversion from the heat source. When the coolant flows through the radiant radiator 14, the heat is transferred to the radiant radiator 14. Heat pipes 15 are installed on the radiant radiator 14, and the heat is transferred to the radiant fins 16 through the heat pipes 15. A heat insulation layer is added to the bottom of the radiant fins 16 to shield the heat from radiation to the spacecraft. Finally, the heat is discharged into space through radiation.

[0066] In one embodiment, the top of the radiant radiator 14 is connected to the heat exchanger 17, the heat exchanger 17 is connected to the circulating fluid pump 18 through a potassium coolant circuit, and the other end of the circulating fluid pump 18 is connected to the bottom of the radiant radiator 14, forming a space heat pipe radiant cooling system.

[0067] Furthermore, the power output is transmitted to the electric propulsion subsystem or other electrically powered payloads through the organic connection structure between the modules. Electric propulsion (or electric propulsion) refers to the use of electrical energy to heat, dissociate, and accelerate the working propellant, creating a high-speed jet to generate thrust. Electric propulsion is characterized by high specific impulse and light mass, making it a current hot topic in satellite applications. To date, more than 160 satellites and interplanetary probes have used electric propulsion technology. The main differences between different electric propulsion systems lie in the construction and working principle of the thruster. Based on the method of heating the working propellant, electric propulsion can be divided into three types: electrothermal, electrostatic, and electromagnetic. Correspondingly, electric rocket engines are divided into three types: electrothermal rocket engines, electrostatic rocket engines, and electromagnetic rocket engines. Electrothermal thrusters use electrical energy to heat the working propellant and vaporize it, which is then expanded and accelerated through a nozzle to generate thrust. These can generally be divided into resistance heating, arc heating, and microwave heating types. Electrostatic thrusters use electrical energy to dissociate the working propellant in an electrostatic field, forming electrons and ions, which are then accelerated and expelled under the influence of the electrostatic field. Electrostatic thrusters, also known as ion thrusters, and Hall thrusters are two popular types of electric propulsion systems. Ion thrusters separate the ionization region from the acceleration region, offering high specific impulse but are technically complex.

[0068] In one embodiment, this application selects to use an electromagnetic rocket engine. Electromagnetic thrusters utilize electrical energy to form a plasma from a working propellant (hydrogen, helium, argon, lithium vapor, etc.), which is then accelerated and ejected from the nozzle under the Lorentz force of an applied electromagnetic field. Hall thrusters are a type of electromagnetic propulsion system and one of the two currently popular electric propulsion technologies. The principle of a Hall thruster is to confine electrons in a magnetic field and use the electrons to ionize the propellant, accelerating ions to generate thrust and neutralizing the ions in the plume. The ionization and acceleration regions of a Hall thruster are located in the same area; compared to ion thrusters, the technology is simpler but has a lower specific impulse.

[0069] The modular nuclear reactor power supply device provided in this application significantly reduces fuel weight and propellant consumption compared to chemical propulsion schemes, thereby substantially increasing propulsion power per unit fuel and raising specific impulse by an order of magnitude. Compared to solar power schemes, this nuclear power scheme effectively avoids power supply instability caused by shading or variations in solar energy reception efficiency. Compared to nuclear decay power schemes, this nuclear power scheme significantly increases output, supporting large-scale space missions where nuclear decay power is insufficient.

[0070] Because the nuclear reactor power unit provided in this application adopts a modular design, each module can achieve the overall power output of the unit by being connected in parallel with other power output subsystem modules 1. This design can effectively reduce the system complexity and construction cost of the nuclear power conversion facilities within a single module, improve the system reliability of the nuclear reactor power unit as a whole, and improve the overall mission reliability and system economy of the deep space shuttle spacecraft. Also thanks to the modular design, the modules can be mass-produced and customized for on-orbit assembly according to different mission requirements, thereby significantly reducing the design cost and preparation cycle of space missions and improving the reliability of the power system.

[0071] In one embodiment, the modular nuclear reactor power supply unit compartment shell 2 provided in this application is an aluminum alloy shell with graphite coated on the outer surface, or a titanium alloy shell with graphite coated on the outer surface; two docking mechanisms 3 are arranged opposite each other on the compartment shell 2, and two adjacent power output subsystem compartments 1 are assembled through the docking mechanisms 3.

[0072] In one embodiment, the reactor 6 of the modular nuclear reactor power device provided in this application is a fast neutron reactor; the reactor core includes a central control rod, and an inner fuel assembly, an outer fuel assembly, and a reflector layer that are sequentially surrounded by the central control rod; a number of control drums are distributed in a ring shape within the reflector layer; a number of coolant channels are formed between the outer fuel assembly and the reflector layer; the inner fuel assembly and the outer fuel assembly are respectively columnar fuel assemblies with a hexagonal cross-section, and a shadow shielding structure 8 is provided around the reactor 6.

[0073] In one embodiment, the power adapter 4 of the modular nuclear reactor power supply device provided in this application is connected to multiple power output subsystem modules 1, forming a parallel connection with the multiple power output subsystem modules 1, and outputs the power generated by the multiple power output subsystem modules 1 in a parallel manner. The power output subsystem modules 1 output electrical energy to the load end through the power adapter 4; the load end is a power-consuming unit, which includes a payload module 19 and an electric propulsion device. The power adapter 4 is provided with a connection mechanism 5, which is adapted to the load end. The power adapter 4, as a power output system, outputs the generated electrical energy from the module and connects it in parallel with other power modules, ultimately delivering the electrical energy to the power load end according to mission requirements.

[0074] In the modular nuclear reactor power supply device provided in this application, the docking method between two adjacent power output subsystem modules can be adopted in various ways, such as: ① when it supplies power to the space station, a single module is launched and docked with the space station to meet most of the space station's power needs; ② when it supplies power to the star table base, multiple modules are launched independently, and there is no need to assemble the modules; they are connected in parallel for power supply; ③ when it supplies power to the deep space shuttle propulsion, multiple modules are launched independently, and two adjacent modules are assembled side by side and connected in parallel for power supply.

[0075] See Figure 7 and Figure 8 When the modular nuclear reactor power supply device provided in this application is applied to deep space shuttle propulsion, both the payload section 19 and the electric propulsion device 20 are placed behind the shadow shielding structure 8 of the power output subsystem section 1. The power output subsystem section assembly and the electric propulsion device are located at opposite ends of the payload section.

[0076] The main structure of the modular nuclear reactor power supply device provided in this application consists of several modular power output subsystem modules 1 interconnected, which can be used as a nuclear reactor power supply device for commercial deep space shuttle spacecraft.

[0077] In one embodiment, the core component of the modular nuclear reactor power supply device provided in this application is a small helium-xenon cooled fast neutron reactor with a thermal power of 1 megawatt. It adopts a single-loop layout, with the core, coolant, and nuclear thermoelectric converter housed within the power output subsystem compartment. The final heat sink for the power output subsystem is located outside the compartment. The reactor is cooled by a mixture of helium and xenon gases. The gas cooling the core is forced to circulate into the helium-xenon turbine, removing heat from the core and generating electricity at the turbine. The fuel elements in the core are low-enriched uranium fuel with a U-235 enrichment of no more than 20 wt%. The low-enriched uranium fuel can be manufactured from UO2, U3Si2, or metallic uranium. Fuel manufactured using uranium dioxide has undergone thorough reactor testing and the process is relatively mature, further reducing the cost and time required for system development.

[0078] The power output subsystem module can be configured with different power outputs by varying numbers of power output subsystem modules, which makes it easy for the nuclear reactor power supply unit to be configured with different modules to provide different levels of power according to the needs of different space missions.

[0079] The technical features of the above embodiments can be combined in any way (as long as there is no contradiction in the combination of these technical features). For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; these embodiments not explicitly written should also be considered to be within the scope of this specification.

[0080] The present application has been described in a relatively specific and detailed manner above through general descriptions and specific embodiments. It should be understood that, based on the technical concept of the present application, several conventional adjustments or further innovations can be made to these specific embodiments; however, as long as they do not depart from the technical concept of the present application, the technical solutions obtained by these conventional adjustments or further innovations also fall within the protection scope of the claims of the present application.

Claims

1. A modular nuclear reactor power supply device, characterized in that, The system comprises multiple power output subsystem sections. Each power output subsystem section includes a section shell, a final heat sink located outside the section shell, a power adapter located at one end of the section shell, and a reactor, a helium-xenon thermoelectric conversion circuit, and a shadow shielding structure located inside the section shell. The shadow shielding structure is used to shield the reactor core from radiation. A coolant channel is formed inside the reactor, through which a helium-xenon mixed gas is introduced. The helium-xenon mixed gas circulates in the helium-xenon thermoelectric conversion circuit to remove heat from the reactor core and generate electrical energy. The power adapter is connected to the helium-xenon thermoelectric conversion circuit to convert the electrical energy output by the circuit into a desired voltage value adapted to the load and then output it to the load. The power adapter is connected to multiple power output subsystem sections in parallel to achieve power output. The reactor is a fast neutron reactor; the reactor core includes a central control rod, and an inner fuel assembly, an outer fuel assembly, and a reflector layer that are sequentially surrounded by the central control rod; several control drums are distributed in a ring shape within the reflector layer; several coolant channels are formed between the outer fuel assembly and the reflector layer; The inner and outer fuel assemblies are both hexagonal columnar fuel assemblies, and the fuel in the columnar fuel assemblies is UO2 with a U-235 enrichment of less than 20 wt%. The shadow shielding structure is provided around the reactor. The power adapter is a voltage conversion device. The power adapter is connected to multiple power output subsystem modules and forms a parallel connection with the multiple power output subsystem modules, and outputs the power of the electrical energy generated by the multiple power output subsystem modules in a parallel manner. The power output subsystem section outputs electrical energy to the load end through the power adapter; The load end is an electrical unit, which includes a payload compartment and an electric propulsion device; The power adapter is equipped with a connection mechanism, which is adapted to connect to the load end.

2. The modular nuclear reactor power supply device according to claim 1, characterized in that, The outer shell of the compartment is an aluminum alloy shell with graphite coated on the outer surface, or a titanium alloy shell with graphite coated on the outer surface. Two docking mechanisms are arranged opposite each other on the outer shell of the compartment, and two adjacent power output subsystem compartments are assembled through the docking mechanisms.

3. The modular nuclear reactor power supply device according to claim 1, characterized in that, The shadow shielding structure is a frustum-shaped shell structure; the sidewall of the shell structure includes three radiation shielding layers, namely: a light component shielding layer, a heavy component shielding layer, and a thermal shielding layer; the light component shielding layer is used to reduce neutron flux, the heavy component shielding layer is used to reduce gamma radiation, and the thermal shielding layer is used to reduce radiative heat; The light component shielding layer is made of lithium hydride. The recombinant shielding layer is made of tungsten. The heat shielding layer is made of boron-containing stainless steel.

4. The modular nuclear reactor power supply device according to claim 1, characterized in that, The coolant channel is connected to the helium-xenon thermoelectric conversion circuit; the helium-xenon thermoelectric conversion circuit includes several gas transmission pipelines, and a compressor, a regenerator, a turbine, and a cooler connected through the gas transmission pipelines; the gas output from the coolant channel is compressed and pressurized by the compressor, enters the regenerator for preheating, and then enters the reactor core for heating. The heated gas enters the turbine for expansion and work, then enters the regenerator to release waste heat, then enters the cooler for cooling, and finally flows back to the compressor to form a helium-xenon mixed gas cycle; the waste heat of the cooler is discharged through a radiant radiator.

5. The modular nuclear reactor power supply device according to claim 4, characterized in that, The radiant radiator includes multiple radiant radiator units, each equipped with heat pipes and radiant fins. A heat insulation layer is installed at the bottom of the radiant fins. When the flowing helium-xenon mixed gas absorbs waste heat discharged from the heat source through the helium-xenon thermoelectric conversion circuit, the heat is transferred to the radiant radiator as it flows through it. The heat is then transferred to the radiant fins via the heat pipes. The heat insulation layer shields the spacecraft from heat radiation, and the heat is discharged into space through radiation.

6. The modular nuclear reactor power supply device according to claim 1, characterized in that, The electric propulsion device includes several electric propulsion subsystems, and several electric output subsystem sections supply power to the electric propulsion subsystems through electric adapters on them.

7. The modular nuclear reactor power supply device according to claim 1, characterized in that, When the modular nuclear reactor power supply provides power for deep space shuttle propulsion, the payload compartment and the electric propulsion device are both placed behind the shadow shielding structure of the electric output subsystem compartment; the electric output subsystem compartment and the electric propulsion device are arranged opposite each other at both ends of the payload compartment.

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