Radiation regulation structure-based spatial photovoltaic-phase change-thermoelectric coupling power generation system and method

Abstract

The application discloses a space photovoltaic-phase change-thermoelectric coupling power generation system and method based on radiation regulation structure, which is composed of a condenser, a diffuser, a conical reflector, a photovoltaic cell, a phase change material, a thermoelectric element, a heat sink and a support; the condenser-diffuser structure composed of the condenser, the diffuser and the conical reflector can improve the power generation of the photovoltaic cell and the thermoelectric element, reduce energy loss, reduce the local temperature of the surface of the photovoltaic cell, and further improve the photovoltaic power generation efficiency and the total power generation efficiency of the system; the cylindrical coupling structure can make the incident solar radiation and the heat radiated by the photovoltaic cell experience multiple reflection-absorption processes in the cylindrical cavity, improve the power generation of the photovoltaic cell and the thermoelectric element, and efficiently utilize solar energy; the radial passive radiation heat sink is beneficial to reducing the system temperature, reducing the amount of heat sink material and the weight of the system, and realizing higher energy conversion efficiency and power density.

Description

Technical Field

[0001] This invention relates to the fields of efficient capture and utilization of solar energy in outer space, photovoltaic power generation, semiconductor thermoelectric power generation, phase change temperature control / energy storage, radiation regulation and refrigeration, and particularly to a space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation regulation structure and its working method. Background Technology

[0002] Solar energy is a clean, widely distributed, and abundant new energy source. Given the dwindling fossil fuel resources, the efficient utilization of solar energy is essential. Photovoltaic power generation technology has attracted much attention because it directly converts solar energy into electricity without intermediate processes. However, ground-based photovoltaic power generation systems are affected by environmental factors such as day-night cycles, weather, and geographical location, making continuous operation difficult and resulting in unstable power output, posing significant challenges to practical applications. Space photovoltaic power generation technology, operating in outer space, is characterized by its immunity to atmospheric interference, stable incident solar radiation, and extremely low ambient temperatures conducive to heat dissipation, thus overcoming the impact of these environmental conditions on the power generation system's performance. In the current operation of space photovoltaic cells, although most solar radiation is received by the photovoltaic cell surface, only a small portion is used to generate electricity. The remaining radiant energy is converted into heat, raising the photovoltaic cell temperature and reducing photoelectric conversion efficiency. To prevent a sharp decline in photovoltaic cell efficiency, active cooling is typically used to lower the photovoltaic cell temperature. However, active cooling requires additional power, reducing the net output power of the photovoltaic system; furthermore, most of the energy is carried away as heat, hindering the full utilization of solar energy. Phase change cooling, as a passive cooling technology, offers advantages such as safety, stability, and excellent heat storage / temperature control without consuming additional power, making it widely used in various electronic component cooling and heat energy storage and recovery devices. Furthermore, thermoelectric elements, due to their ability to directly convert low-grade heat energy into high-grade electrical energy through the Seebeck effect, are also used in many waste heat recovery applications. If photovoltaic cells, phase change materials, and thermoelectric elements can be combined to form a photovoltaic-phase change-thermoelectric coupled power generation system, utilizing the heat storage and temperature control properties of the phase change material to control the temperature of the hot ends of the photovoltaic cells and thermoelectric elements, and using the thermoelectric elements to recover and reuse excess heat for further power generation, then the system's utilization of solar energy will be more efficient, and both system power generation efficiency and output power can be significantly improved.

[0003] Photovoltaic-phase change material-thermoelectric coupling power generation systems have advantages such as low temperature rise, high power generation efficiency, simple structure with no moving parts, and convenient maintenance, and have broad application prospects in the field of solar power generation. However, existing photovoltaic-phase change-thermoelectric coupling systems mainly have the following problems: When sunlight shines on the surface of photovoltaic cells, due to the surface reflection, some photons that should be used to generate electricity cannot be fully utilized and are reflected into the space environment, resulting in a reduction in the system's power generation. At the same time, due to the high emissivity of the photovoltaic cell surface, some energy is lost into the space environment in the form of thermal radiation, resulting in energy waste. In addition, in order to improve the power generation of photovoltaic systems, concentrating methods are often used. However, in concentrated photovoltaic systems, due to the high heat flux density and uneven heat flux distribution on the surface of photovoltaic cells, the cell temperature rises rapidly and the local temperature becomes too high, increasing the difficulty of temperature control and making local cell failures more likely. In addition, in the coupling system, the cold end of the thermoelectric element needs to dissipate heat into the environment in a timely manner to maintain the temperature difference between the hot and cold ends. Active cooling methods often require additional power consumption, resulting in a significant reduction in the system's net output power. Heat pipe cooling devices commonly used in aerospace are expensive to manufacture and require additional fluid, increasing the overall system cost and weight, and also posing a risk of fluid leakage. These issues result in high temperatures, low power generation and efficiency in space photovoltaic-phase change-thermoelectric coupling systems, and high manufacturing, maintenance, and launch costs, hindering the efficient utilization of solar energy and the widespread adoption of space photovoltaic power generation technology. Summary of the Invention

[0004] The purpose of this invention is to overcome the design defects of traditional space photovoltaic power generation systems and provide a space photovoltaic-phase change-thermoelectric coupling power generation system and its operating method based on a radiation regulation structure. This system improves solar energy capture efficiency through the focusing effect of a concentrator; reduces the local energy flux density on the photovoltaic cell surface and lowers the surface temperature through the radiative divergence effect of a diffuser and a conical reflector, thereby improving the photovoltaic cell's power generation efficiency; the cylindrical structure of the photovoltaic-phase change-thermoelectric coupling system allows the radiative energy reflected by the photovoltaic cells and the radiative energy emitted by the cells to be reflected multiple times within the cylindrical cavity and ultimately absorbed, improving the utilization rate of solar energy and the power generation of the coupling system; and the radial radiative heat sink structure fully utilizes the heat dissipation area at the root of the heat sink fins, enabling efficient heat dissipation to the environment, effectively reducing the system temperature, and reducing the amount of heat sink material used, which is beneficial for the lightweight design of the system. This system has advantages such as high solar energy capture and utilization rate, high power generation efficiency and output, and small weight.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A space photovoltaic-phase change-thermoelectric coupling power generation system based on a radiation-controlled structure is disclosed. The system includes a concentrator 2, a diffuser 3, a conical reflector 4, photovoltaic cells 5, a phase change material 6, thermoelectric elements 7, a heat sink 8, and a support 9. The photovoltaic cells 5, phase change material 6, and thermoelectric elements 7 are all cylindrical shell structures arranged sequentially from the inside out to form a cylindrical photovoltaic-phase change-thermoelectric coupling system. The interfaces between the photovoltaic cells 5, phase change material 6, and thermoelectric elements 7 are fixedly connected. The concentrator 2 and diffuser 3... Both the conical reflector 4 and the cylindrical photovoltaic-phase change-thermoelectric coupling system are fixedly connected to the support 9. The conical reflector 4 is placed in the cylindrical cavity surrounded by the photovoltaic cell 5, and its axial length is equal to that of the photovoltaic cell 5. The light-receiving surface of the photovoltaic cell 5 faces the conical reflector, and the other side surface is fixedly connected to the phase change material 6. One side of the phase change material 6 is fixedly connected to the photovoltaic cell 5, and the other side is fixedly connected to the hot end face of the thermoelectric element 7. The hot end face of the thermoelectric element 7 is fixedly connected to the phase change material 6, and the cold end face is fixedly connected to the heat sink 8.

[0007] The condenser lens 2 is a circular convex lens with a radius equal to the vertical length from the axis of the cylindrical photovoltaic-phase change-thermoelectric coupling system to the end of the heat sink 8 fin. It is made of low-density, lightweight, and transparent optical material and serves to capture and converge solar radiation 1.

[0008] The astigmatism mirror 3 is a circular concave lens with a radius equal to the vertical length from the axis of the cylindrical photovoltaic-phase change-thermoelectric coupling system to the light-receiving surface of the photovoltaic cell 5. It uses a low-density, lightweight, and transparent optical material to convert the solar radiation 1 focused by the condenser mirror 2 into parallel light, thereby achieving uniform incident light.

[0009] The axial length of the conical reflector 4 is the same as the length of the photovoltaic cell 5. It is made of acrylic or other lightweight optical mirror materials. It uniformly reflects the light that is focused onto its surface by the condenser 2 and the diffuser 3 onto the photovoltaic cell 5, thereby achieving a more uniform energy flux density, lower local temperature, and higher photovoltaic power generation efficiency on the surface of the photovoltaic cell 5.

[0010] The photovoltaic cell 5 can be made of gallium arsenide or silicon materials, and can be a flexible or rigid small-sized battery cell array arranged in the shape of a cylindrical shell, with its light-receiving surface facing the conical reflector 4; the photovoltaic cell 5 receives the radiation energy reflected by the conical reflector 4 and generates electricity through the photoelectric effect.

[0011] The phase change material 6 can be a composite phase change material of paraffin and metal foam with stable and safe thermophysical properties. The container of the phase change material 6 can be a metal such as aluminum or copper, with an axial length equal to that of the photovoltaic cell 5. One side is fixedly connected to the photovoltaic cell 5, and the other side is fixedly connected to the hot end face of the thermoelectric element 7. The phase change material 6 absorbs and stores the heat from the photovoltaic cell 5 and undergoes a solid-liquid phase change, thereby playing a role in precisely controlling the temperature of the photovoltaic cell 5 and the hot end of the thermoelectric element 7.

[0012] The axial length of the thermoelectric element 7 is equal to that of the photovoltaic cell 5. The thermoelectric element 7 includes an alumina ceramic insulating layer and bismuth telluride thermoelectric leads. The heat released by the phase change material 6 is transferred through the hot end face of the thermoelectric element 7, while the cold end face is cooled by the heat sink 8. A temperature difference is generated between the hot and cold ends of the thermoelectric element 7, which utilizes the Seebeck effect to achieve thermoelectric power generation and improve the power output of the system.

[0013] The heat sink 8 is made of aluminum or other lightweight, high thermal conductivity materials. The cylindrical shell of the heat sink 8 covering the cold end of the thermoelectric element 7 has an axial length equal to that of the photovoltaic cell 5 and is fixedly connected to the cold end face of the thermoelectric element 7. The extended surface exists in the form of radial fins and is fixedly connected to the cylindrical shell of the heat sink 8. The surface of the heat sink 8 is coated with a high emissivity coating, and the radial structure allows the area at the root of the fins to be fully utilized, thus achieving higher heat dissipation efficiency while using less material and lighter weight. The heat sink 8 can achieve efficient heat dissipation, reduce the temperature of the photovoltaic cell 5 and the cold end of the thermoelectric element 7, ensure the full regeneration of the phase change material 6, and improve the photoelectric conversion, thermoelectric conversion efficiency, and overall system efficiency and power density.

[0014] The bracket 9 fixes the condenser lens 2, the astigmatism lens 3 and the conical reflector 4 to the cylindrical photovoltaic-phase change-thermoelectric coupling system.

[0015] The working method of the space photovoltaic-phase change-thermoelectric coupling power generation system based on the radiation regulation structure is as follows: the concentrator 2 captures and focuses solar radiation 1 to obtain more solar incident energy and power generation; in order to be better utilized by the photovoltaic cell 5 for power generation, the focused solar radiation 1 needs to be diffused into parallel light by the astigmatism mirror 3, and then reflected onto the light-receiving surface of the photovoltaic cell 5 by the conical reflector 4; the conical reflector 4 can uniformly reflect the focused high energy flux density solar radiation 1 onto the light-receiving surface of the photovoltaic cell 5, improve the uniformity of the energy flux density on the surface of the photovoltaic cell 5, and realize the function of reducing the temperature of the photovoltaic cell 5 and improving the photovoltaic power generation efficiency; after the reflected radiation reaches the photovoltaic cell 5, part of the radiation energy is absorbed by the photovoltaic cell and converted into electrical energy or heat energy, while the remaining unabsorbed radiation energy, together with the radiation heat of the photovoltaic cell 5 itself, will eventually undergo the absorption-power generation or absorption-heat generation process after multiple reflections in the cylindrical cavity; After absorbing heat from the photovoltaic cell 5, the phase change material 6 accumulates more heat. When its temperature reaches its melting point, it begins to melt (solid-liquid phase change). Utilizing its advantages such as large latent heat and stable melting point, it precisely controls the temperature of the photovoltaic cell 5, playing a dual role of heat storage and temperature control. While absorbing heat from the photovoltaic cell 5, the phase change material 6 also releases heat to the hot end of the thermoelectric element 7. After receiving heat from the phase change material 6, the thermoelectric element 7 uses the Seebeck effect to generate electricity through thermoelectric difference, providing more power. At the same time, the waste heat not used for power generation is dissipated into the environment through the heat sink 8 connected to the cold end of the thermoelectric element 7. The surface of the heat sink 8 is coated with a high emissivity coating, and its radial surface structure makes full use of the heat dissipation area at the root of the heat sink fins. Therefore, it is possible to reduce the amount of heat sink 8 material while effectively reducing the temperature of the photovoltaic cell 5 and the cold end of the thermoelectric element 7, achieving the lightweight design goal of the space system.

[0016] The advantages of this invention are as follows: Based on the radiation trapping and regulation effect of the concentrating-diffusing structure composed of a concentrating mirror, a astigmatizing mirror, and a conical reflector, the radiation escape prevention effect of the cylindrical coupling structure, and the radiation cooling effect of the radial heat sink structure, this invention effectively solves the shortcomings of existing concentrating photovoltaic-phase change-thermoelectric coupled power generation systems, such as low solar energy utilization rate, uneven local heat flux density on the surface of photovoltaic cells, excessively rapid temperature rise, sharp decrease in efficiency, large heat dissipation load, large weight of heat dissipation equipment, and high cost. It can not only realize the utilization of solar incident energy in multiple forms (light and heat) and reduce energy loss and waste, but also effectively improve the uniformity of energy flux density on the surface of photovoltaic cells, reduce the temperature of photovoltaic cells and the cold end temperature of thermoelectric elements, and improve the total power generation power and power generation efficiency of the system. This system utilizes a focusing-diffusing structure composed of lenses and mirrors. This increases the capture of solar incident energy while improving the surface energy flux density and temperature uniformity of the photovoltaic cells, reducing local cell temperatures and improving power generation efficiency. The cylindrical coupling structure prevents most of the radiant energy from escaping and dissipating into the environment, improving solar energy utilization and system power output. The radial heat sink structure fully utilizes the heat dissipation area at the base of the heat sink fins, increasing the heat dissipation rate per unit surface area and reducing the amount of actual heat sink material required, thus achieving the weight reduction goals for the heat sink and coupling system. This invention offers advantages such as high solar energy utilization, high power generation efficiency and output, light weight, and low cost. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the spatial photovoltaic-phase change-thermoelectric coupling power generation system based on the radiation regulation structure of the present invention.

[0018] Figure 2 This is a schematic diagram of the cylindrical photovoltaic-phase change-thermoelectric coupling system of the present invention.

[0019] Figure 3 This is a schematic diagram of the working model of the present invention.

[0020] Among them: 1-Solar radiation, 2-Condenser lens, 3-Diffuser lens, 4-Conical reflector, 5-Photovoltaic cell, 6-Phase change material, 7-Thermoelectric element, 8-Heat sink, 9-Support. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] See Figure 1 A space photovoltaic-phase change-thermoelectric coupled power generation system based on radiation regulation structure is composed of a concentrator 2, a diffuser 3, a conical reflector 4, a photovoltaic cell 5, a phase change material 6, a thermoelectric element 7, a heat sink 8, and a support 9.

[0023] The connection relationships between the various components are described in detail below:

[0024] See Figure 1 and Figure 2 The condenser lens 2 is a circular convex lens with a radius equal to the vertical length from the axis of the cylindrical coupling system to the end of the heat sink 8 fin. Its principal optical axis coincides with the axis of the cylindrical photovoltaic-phase change-thermoelectric coupling system. It is made of a low-density, lightweight, transparent optical material. The astigmatism lens 3 is a circular concave lens with a principal optical axis coincident with the axis of the cylindrical photovoltaic-phase change-thermoelectric coupling system. Its radius is equal to the vertical length from the axis of the cylindrical photovoltaic-phase change-thermoelectric coupling system to the light-receiving surface of the photovoltaic cell 5. It is made of a lightweight, light-transmitting optical material. The conical reflector 4 has the same axial length as the photovoltaic cell 5, and its surface is conical. It is made of acrylic or other lightweight optical mirror material and is placed in the cylindrical cavity surrounding the photovoltaic cell 5. The central axis of the conical reflector 4 coincides with the central axis of the cylindrical cavity surrounding the photovoltaic cell 5. The condenser lens 2, the astigmatism lens 3, and the conical reflector 4 are fixedly connected to the cylindrical photovoltaic-phase change-thermoelectric coupling system through the bracket 9. The photovoltaic cell 5 forms a cylindrical shell, with its light-receiving surface facing the conical reflector 4. The back side is fixedly connected to the phase change material 6, which is a gallium arsenide or silicon-based battery. The axial length of the phase change material 6 is equal to the length of the photovoltaic cell 5. One side is fixedly connected to the photovoltaic cell 5, and the other side is fixedly connected to the hot end face of the thermoelectric element 7. The material is a stable and safe paraffin-based and metal foam composite phase change material. The axial length of the thermoelectric element 7 is equal to the length of the photovoltaic cell 5. Its hot end face is fixedly connected to the phase change material 6, and its cold end face is fixedly connected to the heat sink 8. The thermoelectric element 7 is made of oxide... It is composed of aluminum ceramic and bismuth telluride; the heat sink 8 has an axial length equal to that of the photovoltaic cell 5, and includes a cylindrical shell and an extended surface. The cylindrical shell is fixedly covered on the cold end face of the thermoelectric element 7, and the extended surface exists in the form of radial fins. The fins are arranged radially and have equal radial lengths and are fixedly connected to the cylindrical shell. The surface of the heat sink 8 is coated with a high emissivity coating; the bracket 9 sequentially fixes the condenser lens 2, the astigmatism lens 3, the conical reflector 4 and the cylindrical photovoltaic-phase change-thermoelectric coupling system.

[0025] This invention discloses a space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation-controlled structure. It can efficiently capture and utilize solar radiation energy, improve the surface energy flux density and temperature uniformity of photovoltaic cells, and maintain a low system temperature and high system power generation efficiency while increasing power output. Furthermore, it achieves a high heat dissipation rate with less heat sink material, effectively reducing system weight, increasing power density, and achieving the lightweight design goal of the space system. Its operation mode is described in detail below:

[0026] See Figure 3In operation, the concentrator 2 faces solar radiation 1, with its principal optical axis parallel to the direction of solar radiation 1. The concentrator 2 focuses the solar radiation 1 onto the astigmatism mirror 3, thus capturing more of the solar radiation 1. The astigmatism mirror 3 converts the solar radiation 1 focused by the concentrator 2 into parallel light, allowing the solar radiation 1 to better enter the side opening of the cylindrical photovoltaic-phase change-thermoelectric coupling system. After being converted into parallel light by the astigmatism mirror 3, the solar radiation 1 reaches the surface of the conical reflector 4, which uniformly reflects the parallel light onto the light-receiving surface of the photovoltaic cell 5, increasing the energy flux density and temperature on the surface of the photovoltaic cell 5. Uniformity is achieved to reduce the temperature of photovoltaic cell 5 and improve photovoltaic power generation efficiency. After solar radiation 1 reaches photovoltaic cell 5, some of the radiant energy is absorbed by the cell and converted into electrical energy or heat energy. The remaining unabsorbed radiant energy, along with the radiant heat of photovoltaic cell 5 itself, undergoes multiple reflections within the cylindrical cavity and eventually experiences absorption-power generation or absorption-heat generation. As the temperature of photovoltaic cell 5 increases, the temperature of phase change material 6 also increases due to heat transfer. When the temperature of phase change material 6 reaches its melting point, a solid-liquid phase transition begins. At this point, most of the heat is stored in the phase change material as latent heat. In step 6, the temperature rise of the photovoltaic cell 5 becomes very slow, thus storing heat and precisely controlling its temperature. While absorbing and storing heat from the photovoltaic cell 5, the phase change material 6 also releases heat to the hot end of the thermoelectric element 7. The hot end of the thermoelectric element 7 absorbs heat from the phase change material 6, while the cold end dissipates heat through the heat sink 8, creating a temperature difference between the two ends of the thermoelectric element 7. This temperature difference generates electricity through the Seebeck effect of the semiconductor, providing additional electrical power output. Of the heat entering the thermoelectric element 7, a portion is used to generate electricity, and the remainder is dissipated through the heat sink 8 connected to the cold end of the thermoelectric element 7. The heat sink 8 dissipates heat into the outer space environment through radiation. The high emissivity coating and radial structure on the surface of the heat sink 8 can reduce the temperature of the cold end of the thermoelectric element 7 and the temperature of the photovoltaic cell 5, promote the regeneration of the phase change material 6, increase the heat dissipation rate per unit area, reduce the amount of material used in the heat sink 8, and reduce the weight and cost of the heat sink 8 and the entire system. Except for the light-receiving surface of the photovoltaic cell 5, the heat dissipation surface of the heat sink 8, the surfaces of the condenser lens 2, the diffuser lens 3, the conical reflector 4 and the support 9, all other surfaces of the coupled power generation system are heat-insulated to reduce the system's heat dissipation and improve energy utilization.

[0027] The embodiments of the present invention have been described in detail above. This specification illustrates the present invention with specific examples. The specific implementation methods and application scope should not be limited to this specification, and this specification should not be construed as a limitation of the present invention.

Claims

1. A space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation-controlled structure, characterized in that: The system includes a condenser (2), a diffuser (3), a conical reflector (4), a photovoltaic cell (5), a phase change material (6), a thermoelectric element (7), a heat sink (8), and a support (9); wherein, the photovoltaic cell (5), the phase change material (6), and the thermoelectric element (7) are all cylindrical shell structures and are arranged sequentially from the inside to the outside to form a cylindrical photovoltaic-phase change-thermoelectric coupling system, and the interfaces of the photovoltaic cell (5), the phase change material (6), and the thermoelectric element (7) are all fixedly connected; the condenser (2), the diffuser (3), and the conical reflector (4) are all fixedly connected to the cylindrical photovoltaic-phase change-thermoelectric coupling system through the support (9), and the condenser (2) The principal optical axis of the astigmatism mirror (3) and the conical axis of the conical reflector (4) are both coincident with the axis of the cylindrical photovoltaic-phase change-thermoelectric coupling system; the condenser (2) and the astigmatism mirror (3) are outside one side port of the cylindrical photovoltaic-phase change-thermoelectric coupling system, and the conical reflector (4) is inside the hollow part enclosed by the cylindrical photovoltaic-phase change-thermoelectric coupling system; the other side port of the cylindrical coupling system is closed; the heat sink (8) is wrapped around the outermost side of the cylindrical photovoltaic-phase change-thermoelectric coupling system and is fixedly connected to the cold end of the thermoelectric element (7). The heat sink (8) includes the cylindrical shell surface that wraps around the cold end of the thermoelectric element (7) and the extended surface that exists in the form of fins.

2. The space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation regulation structure according to claim 1, characterized in that: The condenser lens (2) is a circular convex lens with a radius equal to the vertical length from the axis of the cylindrical photovoltaic-phase change-thermoelectric coupling system to the end of the heat sink (8) fin. It is made of low-density, lightweight, and transparent optical material and plays the role of capturing and converging solar radiation (1).

3. The space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation-controlled structure according to claim 1, characterized in that: The astigmatism lens (3) is a circular concave lens with a radius equal to the vertical length from the axis of the cylindrical photovoltaic-phase change-thermoelectric coupling system to the light-receiving surface of the photovoltaic cell (5). It uses low-density, lightweight, and transparent optical materials to convert the solar radiation (1) focused by the condenser lens (2) into parallel light, thereby achieving uniform incident light.

4. A space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation regulation structure according to claim 1, characterized in that: The axial length of the conical reflector (4) is the same as that of the photovoltaic cell (5). It is made of lightweight optical mirror material and serves to uniformly reflect the incident light that is focused onto its surface by the condenser (2) and the astigmatist (3) onto the surface of the photovoltaic cell (5), thereby achieving a more uniform energy flow density and temperature on the surface of the photovoltaic cell (5) and higher photovoltaic power generation efficiency.

5. A space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation regulation structure according to claim 1, characterized in that: The photovoltaic cell (5) is made of gallium arsenide or silicon and consists of flexible or rigid small-sized battery cells arranged in an array in the shape of a cylindrical shell.

6. A space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation-controlled structure according to claim 1, characterized in that: The axial length of the phase change material (6) is equal to that of the photovoltaic cell (5). It is a composite phase change material of paraffin and metal foam with stable thermophysical properties, and plays a role in controlling the hot end temperature of the photovoltaic cell (5) and the thermoelectric element (7).

7. A space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation-controlled structure according to claim 1, characterized in that: The axial length of the thermoelectric element (7) is equal to that of the photovoltaic cell (5). The thermoelectric element (7) includes an alumina ceramic insulating layer and a bismuth telluride thermoelectric pin. It utilizes the heat released by the phase change material (6) to achieve thermoelectric power generation, thereby improving the power generation power and efficiency of the system.

8. A space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation-controlled structure according to claim 1, characterized in that: The heat sink (8) is made of a lightweight, high thermal conductivity material. The axial length of the cylindrical shell of the heat sink (8) covering the cold end of the thermoelectric element (7) is equal to that of the photovoltaic cell (5). The extended surface exists in the form of radial fins and is fixedly connected to the cylindrical shell of the heat sink (8). The surface of the heat sink (8) is coated with a high emissivity coating. The heat dissipation area at the root of the fins of the heat sink (8) is fully utilized to achieve efficient heat dissipation, reduce the temperature of the cold end of the photovoltaic cell (5) and the thermoelectric element (7), ensure that the phase change material (6) is fully regenerated, and play a role in improving the photoelectric conversion efficiency, thermoelectric conversion efficiency, and overall system efficiency.

9. A space photovoltaic-phase change-thermoelectric coupling power generation system based on a radiation regulation structure according to claim 1, characterized in that: Except for the surfaces of the condenser (2) and diffuser (3), the surface of the conical reflector (4), the light-receiving surface of the photovoltaic cell (5), the surface of the heat sink (8), and the surface of the bracket (9), all other outer surfaces are heat-insulated to reduce heat loss and improve the system's energy utilization rate.

10. The operating method of a space photovoltaic-phase change-thermoelectric coupled power generation system based on a radiation modulation structure as described in any one of claims 1 to 9, characterized in that: The concentrator (2) captures and converges solar radiation (1) to obtain solar incident energy. In order to be used by the photovoltaic cell (5) for efficient power generation, the converged solar radiation (1) needs to be diffused into parallel light by the astigmatism mirror (3) and then reflected onto the surface of the photovoltaic cell (5) by the conical reflector (4). The conical reflector (4) can uniformly reflect the converged high energy flux density solar radiation (1) onto the light-receiving surface of the photovoltaic cell (5), improve the uniformity of the energy flux density on the surface of the photovoltaic cell (5), and realize the function of reducing the temperature of the photovoltaic cell (5) and improving the photovoltaic power generation efficiency. After the reflected radiation reaches the photovoltaic cell (5), part of the radiation energy is absorbed by the photovoltaic cell and converted into electrical energy or heat energy. The remaining unabsorbed radiation energy, together with the radiation heat of the photovoltaic cell (5) itself, will eventually undergo the absorption-power generation or absorption-heat generation process after multiple reflections in the cylindrical cavity. The phase change material (6) absorbs the radiation from the photovoltaic cell (5). After absorbing the heat, the heat stored inside increases. When its temperature reaches its melting point, it begins to melt. Taking advantage of its large latent heat and stable melting point, the temperature of the photovoltaic cell (5) can be precisely controlled, playing a dual role of heat storage and temperature control. When the phase change material (6) absorbs the heat from the photovoltaic cell (5), it also releases heat to the thermoelectric element (7). After receiving the heat from the phase change material (6), the thermoelectric element (7) uses the Seebeck effect to generate electricity by temperature difference, which plays the role of converting waste heat into electrical power. At the same time, the waste heat that is not used for power generation is dissipated into the environment through the heat sink (8) connected to the cold end of the thermoelectric element (7). The surface of the heat sink (8) is coated with a high emissivity coating, and its radial structure can make full use of the heat dissipation area at the root of the heat sink (8) fins. Therefore, it can reduce the amount of heat sink (8) material while effectively reducing the temperature of the photovoltaic cell (5) and the cold end of the thermoelectric element (7), thus achieving the goal of lightweight design of the space system.

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