A method and device for calculating the thermoelectric output characteristics of a space heat pipe stack power supply

Abstract

The present invention discloses a method and device for calculating the thermoelectric output characteristics of a space heat pipe pile power supply, which relates to the technical field of space heat pipe pile power supply system simulation. The method comprises the following steps: obtaining power supply system design parameters and power requirements of a nuclear-powered spacecraft in a deep space exploration mission, inputting the power supply system design parameters into a pre-established space heat pipe pile power supply system model, and obtaining processed power supply system design parameters based on the power requirements of the nuclear-powered spacecraft in the deep space exploration mission; receiving a bus voltage reference value of the power supply system, determining a series-parallel connection mode based on the bus voltage reference value of the power supply system, and updating and calculating the processed power supply system design parameters according to the series-parallel connection mode to obtain thermoelectric parameters of the space heat pipe pile power supply under load resistance, thereby providing technical support for the design of a power management system for the nuclear-powered spacecraft.

Description

Technical Field

[0001] The present invention relates to the technical field of space heat pipe pile power supply system simulation, and in particular to a method and device for calculating thermoelectric output characteristics of a space heat pipe pile power supply. Background Art

[0002] Current research focuses primarily on the design and component development of space heat pipe reactor power supplies. Research on the interface integration between space heat pipe reactor power supplies and spacecraft power management systems is relatively limited. Traditional spacecraft primarily rely on solar cells and chemical batteries as their primary energy sources, and understanding of the thermoelectric output characteristics of space heat pipe reactor power supplies is limited. Patent CN110060788A provides a method for analyzing the thermoelectric characteristics of a thermionic space reactor, but its analysis targets thermionic reactors, which differ significantly from heat pipe reactors in their power generation mechanisms. Heat pipe reactors also hold great potential as a power source for deep space exploration missions, and their thermoelectric output characteristics exhibit unique characteristics. Therefore, a calculation method for the thermoelectric output characteristics of space heat pipe reactor power supplies that considers the coupling relationship between the spacecraft power system and the space heat pipe reactor is needed. This method could be used for modeling and simulation of future spacecraft power systems powered by space heat pipe reactors, thereby addressing the technological gap in power management simulation for nuclear-powered spacecraft. Summary of the Invention

[0003] In order to solve the deficiencies mentioned in the above background technology, the purpose of the present invention is to provide a method and device for calculating the thermoelectric output characteristics of a space heat pipe stack power supply.

[0004] In a first aspect, the purpose of the present invention can be achieved by the following technical solution: a method for calculating the thermoelectric output characteristics of a space heat pipe stack power supply, the method comprising the following steps:

[0005] Obtaining power system design parameters and the power requirements of nuclear-powered spacecraft in deep space exploration missions, inputting the power system design parameters into a pre-established space heat pipe reactor power system model, and obtaining processed power system design parameters based on the power requirements of nuclear-powered spacecraft in deep space exploration missions;

[0006] A bus voltage reference value of a power supply system is received, a series-parallel mode is determined based on the bus voltage reference value of the power supply system, and the processed power supply system design parameters are updated and calculated according to the series-parallel mode to obtain thermoelectric parameters of the space heat pipe stack power supply under the load resistance.

[0007] In conjunction with the first aspect, in certain implementations of the first aspect, the method further includes: determining the series-parallel mode based on the bus voltage reference value of the power supply system, and updating the processed power supply system design parameters according to the series-parallel mode, including:

[0008] Initialize the power system design parameters, determine the series and parallel connection mode according to the bus voltage reference value of the power system, set the series load resistance value, perform thermoelectric coupling calculation based on the series load resistance value, and obtain the thermoelectric parameters of the space heat pipe stack power supply under the load resistance value. The thermoelectric parameters of the space heat pipe stack power supply under the load resistance value obtained by completing the calculation when the convergence conditions are met are used as the final thermoelectric parameters of the space heat pipe stack power supply under the load resistance value.

[0009] In combination with the first aspect, in certain implementations of the first aspect, the method further includes: after the thermoelectric parameters of the space heat pipe stack power supply under the load resistance are calculated, a convergence judgment needs to be performed, and the relative difference of the thermoelectric parameters of the space heat pipe stack power supply under two different load resistance values ​​is calculated to determine whether the relative difference meets the convergence condition; if the convergence condition is not met, the thermoelectric parameters of the space heat pipe stack power supply under the load resistance calculated later are used as input conditions for recalculation, and the calculation is terminated when the convergence condition is met.

[0010] In conjunction with the first aspect, in certain implementations of the first aspect, the method further includes: calculating the thermoelectric parameters of the space heat pipe stack power supply under the load resistance, including:

[0011] The core thermal power is calculated using a point reactor neutron kinetic model, and the lumped parameter method is used to solve the heat conduction equation to obtain the average temperature of the reactor core. The thermal resistance network method is used to simulate the heat transfer effect of the heat pipe to obtain the temperature of each area in the heat pipe. The electromotive force of the thermoelectric device is solved based on the Seebeck effect, as well as the current, voltage and electric power generated when the thermoelectric power generation device forms a closed loop with the load, and the radiation waste heat of the radiator is calculated.

[0012] In conjunction with the first aspect, in certain implementations of the first aspect, the method further includes: calculating the core thermal power using a point reactor neutron kinetic model includes:

[0013]

[0014] In the formula is the neutron flux density, for t Responsiveness of the moment, β is the total fraction of delayed neutrons, β i For the i is the share of delayed neutrons in the group, Λ is the neutron generation time, l i It is i The delayed neutron decay constant, C i It is i The concentration of delayed neutron precursor nuclei in the group.

[0015] In conjunction with the first aspect, in certain implementations of the first aspect, the method further includes: solving the heat conduction equation using a lumped parameter method to obtain the average reactor core temperature includes:

[0016]

[0017] in, r F is the fuel density, c F is the specific heat capacity of the fuel, V F is the fuel volume, T F is the average fuel temperature, T HPe is the average temperature of the evaporation section of the heat pipe, R F is the heat transfer resistance between the core fuel and the evaporation section of the heat pipe, q F is the heat release rate of the fuel.

[0018] In conjunction with the first aspect, in certain implementations of the first aspect, the method further includes: simulating the heat transfer effect of the heat pipe using a thermal resistance network method to obtain the temperature of each area in the heat pipe includes:

[0019] The energy conservation equation is used to calculate the transient operating characteristics of a single thermal resistor and obtain the temperature of each area in the heat pipe. The energy conservation equation group is expressed as:

[0020]

[0021]

[0022]

[0023]

[0024] in, r i For the i The density of the thermal resistance, A i For the i The cross-sectional area of ​​the thermal resistance, d i For the i The thickness of the thermal resistance, c p,i For the i The specific heat capacity of a thermal resistance, T i For the i The center temperature of the thermal resistor, T i,1 andT i,2 Respectively i The front and rear temperatures of a thermal resistor, l i It is i The thermal conductivity of the thermal resistance, α i It is i Thermal diffusivity of thermal resistance, Q i,1 and Q i,2 They are i The heat transferred between the front and back ends of a thermal resistor.

[0025] The method for solving the electromotive force of a temperature difference device based on the Seebeck effect includes:

[0026]

[0027] in, a i It is i The Seebeck coefficient of the thermoelectric material used in the temperature difference device is E i It is i The electromotive force of a thermoelectric device, ΔT i is the temperature difference across the thermocouple.

[0028] In conjunction with the first aspect, in certain implementations of the first aspect, the method further includes: a process of calculating the current, voltage, and electric power generated after the thermoelectric power generation device and the load form a closed loop, including:

[0029]

[0030]

[0031]

[0032] Where, I is the current, U is the voltage, P is the electrical power, R i It is i The internal resistance of a temperature difference device, R c is the wire resistance, R load is the load resistance.

[0033] In combination with the first aspect, in certain implementations of the first aspect, the method further includes: the radiant waste heat Q of the radiator rad Calculations include:

[0034]

[0035] in, e is the surface emissivity of the radiation panel, s is the Stefan-Boltzmann constant, A is the radiation panel temperature, T rad is the radiation panel temperature, T space is the space background radiation temperature, and the superscript 4 represents the fourth power of the temperature.

[0036] In a second aspect, in order to achieve the above-mentioned object, the present invention discloses a device for calculating thermoelectric output characteristics of a space heat pipe stack power supply, comprising:

[0037] a parameter processing module for obtaining power system design parameters and the power requirements of nuclear-powered spacecraft in deep space exploration missions, inputting the power system design parameters into a pre-established space heat pipe reactor power system model, and obtaining processed power system design parameters based on the power requirements of nuclear-powered spacecraft in deep space exploration missions;

[0038] The parameter update module is used to receive the bus voltage reference value of the power supply system, determine the series-parallel mode based on the bus voltage reference value of the power supply system, update and calculate the processed power supply system design parameters according to the series-parallel mode, and obtain the thermoelectric parameters of the space heat pipe stack power supply under the load resistance.

[0039] Beneficial effects of the present invention:

[0040] The present invention can provide technical support for the design of power management systems for nuclear-powered spacecraft, thereby facilitating the engineering development of nuclear-powered spacecraft for deep space exploration missions. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0042] Figure 1 1 is a flow chart of the thermoelectric characteristics calculation method of the present invention;

[0043] Figure 2 This is a schematic diagram of the power supply system of a nuclear-powered spacecraft according to the present invention;

[0044] Figure 3 It is a schematic diagram of the overall process of the present invention;

[0045] Figure 4It is a schematic diagram of the architecture of the software for implementing the present invention;

[0046] Figure 5 It is a schematic diagram of the structure of the device of the present invention. DETAILED DESCRIPTION

[0047] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0048] Example 1:

[0049] like Figure 1 As shown, a method for calculating the thermoelectric output characteristics of a space heat pipe stack power supply includes the following steps:

[0050] S101: obtaining power system design parameters and power requirements of nuclear-powered spacecraft in deep space exploration missions, inputting the power system design parameters into a pre-established space heat pipe reactor power system model, and obtaining processed power system design parameters based on the power requirements of nuclear-powered spacecraft in deep space exploration missions;

[0051] S102: Receive the bus voltage reference value of the power supply system, determine the series-parallel mode based on the bus voltage reference value of the power supply system, update and calculate the processed power supply system design parameters according to the series-parallel mode, obtain the thermoelectric parameters of the space heat pipe stack power supply under the load resistance, determine whether the thermoelectric parameters calculated this time have reached a steady state, output the core thermoelectric parameters after reaching a steady state, and end the calculation. If the steady state has not been reached, perform system parameter calculation again.

[0052] The determining of the series-parallel mode based on the bus voltage reference value of the power supply system and updating the processed power supply system design parameters according to the series-parallel mode include:

[0053] The power supply system is a nuclear-powered spacecraft power management system;

[0054] Initialize the power system design parameters, determine the series and parallel connection mode according to the bus voltage reference value of the power system, set the series load resistance value, perform thermoelectric coupling calculation based on the series load resistance value, and obtain the thermoelectric parameters of the space heat pipe stack power supply under the load resistance value. The thermoelectric parameters of the space heat pipe stack power supply under the load resistance value obtained by completing the calculation when the convergence conditions are met are used as the final thermoelectric parameters of the space heat pipe stack power supply under the load resistance value.

[0055] After calculating the thermoelectric parameters of the space heat pipe stack power supply under the load resistance value, convergence is determined. The relative difference between the thermoelectric parameters of the space heat pipe stack power supply under two different load resistance values ​​is calculated. The core temperature and output power of the space heat pipe stack power supply are used as criteria. If the relative difference in core temperature is less than 0.1K and the relative difference in output power is less than 0.1W, the calculation is considered to have reached convergence. If the convergence criteria are not met, the thermoelectric parameters of the space heat pipe stack power supply under the later calculated load resistance value are used as input and recalculated. The calculation ends when the convergence criteria are met.

[0056] The calculation of the thermoelectric parameters of the space heat pipe stack power supply under the load resistance value includes:

[0057] The point reactor neutron kinetic model is a simplified model commonly used in nuclear reactor physics analysis to describe the temporal variation of the neutron flux density within a reactor. This model treats the reactor as a single point, ignoring the spatial distribution of the neutron flux density. It analyzes the dynamic behavior of the neutron flux density within the reactor over time and is suitable for compact core reactors such as space heat pipe reactors.

[0058] The lumped parameter method is a simplified analysis method commonly used in heat transfer to study the temporal evolution of the temperature distribution within an object. This method assumes a uniform temperature distribution within the object, ignoring the spatial distribution of the object's temperature and considering only the temporal evolution of the temperature.

[0059] The thermal resistance network method equates the heat transfer process to thermal resistance. The heat transfer process inside a single thermal resistance is regarded as quasi-steady state. By establishing thermal resistance models for different regions and solving their energy conservation equations, the temperature distribution of each region is obtained. This is a commonly used model for solving the temperature distribution of heat pipes.

[0060] When two different conductors or semiconductor materials are connected into a circuit and maintained at different temperatures at the junction, an electromotive force is generated in the circuit. This phenomenon, which describes the potential difference caused by a temperature gradient, is known as the Seebeck effect. Based on the Seebeck effect, the temperature gradient between the two ends of the space heat pipe reactor's thermoelectric power generation device generates an electromotive force, which, when connected by wires, generates an electric current.

[0061] The core thermal power is calculated using a point reactor neutron kinetic model, and the lumped parameter method is used to solve the heat conduction equation to obtain the average temperature of the reactor core. The thermal resistance network method is used to simulate the heat transfer effect of the heat pipe to obtain the temperature of each area in the heat pipe. The electromotive force of the thermoelectric device is solved based on the Seebeck effect, as well as the current, voltage and electric power generated when the thermoelectric power generation device forms a closed loop with the load. The radiation waste heat of the radiator is calculated based on the principle of radiation heat dissipation.

[0062] The core thermal power is calculated using the point reactor neutron kinetic model, including:

[0063]

[0064] In the formula is the neutron flux density, for t Responsiveness of the moment, β is the total fraction of delayed neutrons, β i For the i is the share of delayed neutrons in the group, Λ is the neutron generation time, l i It is i The delayed neutron decay constant, C i It is i The concentration of delayed neutron precursor nuclei in the group.

[0065] The heat conduction equation is solved using the lumped parameter method to obtain the average temperature of the reactor core:

[0066]

[0067] in, r F is the fuel density, c F is the specific heat capacity of the fuel, V F is the fuel volume, T F is the average fuel temperature, T HPe is the average temperature of the evaporation section of the heat pipe, R F is the heat transfer resistance between the core fuel and the evaporation section of the heat pipe, q F is the heat release rate of the fuel.

[0068] The thermal resistance network method is used to simulate the heat transfer effect of heat pipes. During the operation of a space heat pipe power system, due to the good isothermal properties of the heat pipe, the transient response time of the working fluid flow and heat transfer within the heat pipe is much shorter than the response of the heat conduction between the pipe wall and the wick. The circulation of the working fluid within the heat pipe can be considered as quasi-steady state, and a thermal resistance network model is established. The energy conservation equation is used to calculate the transient operating characteristics of a single thermal resistor, and the temperature of each area within the heat pipe is obtained. The energy conservation equation system can be expressed as:

[0069]

[0070]

[0071]

[0072]

[0073] in, r i For the i The density of the thermal resistance, A i For the i The cross-sectional area of ​​the thermal resistance, d i For the i The thickness of the thermal resistance, c p,i For the i The specific heat capacity of a thermal resistance, T i For the i The center temperature of the thermal resistor, T i,1 and T i,2 Respectively i The front and rear temperatures of a thermal resistor, l i It is i The thermal conductivity of the thermal resistance, α i It is i Thermal diffusivity of thermal resistance, Q i,1 and Q i,2 They are i The heat transferred between the front and back ends of a thermal resistor.

[0074] The Seebeck effect is used to determine the electromotive force of a thermoelectric device. Heat from the nuclear reactor is transferred to the thermoelectric device through a heat pipe. Due to the temperature difference between the two ends of the thermoelectric device, an electromotive force is generated due to the Seebeck effect. The total electromotive force generated by connecting thermoelectric devices in series or parallel can be expressed as:

[0075]

[0076] in, a i It is i The Seebeck coefficient of the thermoelectric material used in the temperature difference device is E i It is i The electromotive force of a thermoelectric device, ΔT i is the temperature difference across the thermocouple.

[0077] After the thermoelectric power generation device and the load form a closed loop, the generated current, voltage and electric power can be expressed as:

[0078]

[0079]

[0080]

[0081] Where, I is the current, U is the voltage, P is the electrical power, R i It is i The internal resistance of a temperature difference device, R c is the wire resistance, R load is the load resistance.

[0082] The system waste heat of the space heat pipe reactor power supply is radiated into space through the radiator heat sink. The background radiation temperature of space is set to 4 K. The calculation of the radiated waste heat can be expressed as:

[0083]

[0084] in, e is the surface emissivity of the radiation panel, s is the Stefan-Boltzmann constant, A is the radiation panel temperature, T rad is the radiation panel temperature, T space is the space background radiation temperature, and the superscript 4 represents the fourth power of the temperature.

[0085] Specifically, the present invention will be further described below through examples:

[0086] like Figure 2 The figure shows the main structure of a nuclear-powered spacecraft power system. The space heat pipe reactor power supply is responsible for providing stable and reliable power for nuclear-powered spacecraft. Compared to conventional chemical power sources such as solar cells, the space heat pipe reactor power supply is more complex, consisting of a reactor core, heat pipes, thermoelectric devices, and radiators. The reactor core generates heat through nuclear fission reactions. This heat is conducted through the evaporator section of the heat pipe within the core to the condenser section of the heat pipe. The condenser section of the heat pipe is welded to the hot end of the thermoelectric device, and heat is transferred to the device through heat conduction. Due to the temperature difference between the hot and cold ends of the thermoelectric device, the thermoelectric material generates an electromotive force based on the Seebeck effect. The thermoelectric device is connected to the circuit load in various series and parallel configurations to form a closed loop, generating a loop current. The electrical energy generated by the space nuclear reactor power supply is transferred to a shunt regulator for shunting and regulation. The shunted electrical energy is then processed by a charge-discharge regulator, which regulates the charge or discharge of the battery pack based on the power demand of the load. The power management system is responsible for the unified allocation of the electrical energy generated by the space heat pipe reactor.

[0087] like Figure 3 The figure shows the calculation process for the thermoelectric output characteristics of a space heat pipe reactor power supply. First, the parameters are initialized, and the series and parallel connection configurations are determined based on the nuclear-powered spacecraft bus voltage, along with the series load resistance values. System parameter calculations are then performed to calculate the thermoelectric parameters of the space heat pipe reactor power supply for different load resistance values. The determination is made as to whether the thermoelectric parameters have reached a steady state. If not, the calculation is iterated until steady state is achieved. Once steady state is achieved, the core thermoelectric parameters are output, and the process concludes.

[0088] like Figure 4 As shown, the software used in conjunction with the calculation method of the present invention is mainly composed of modules such as reactor core, heat pipe, thermoelectric power generation device, radiator, PID controller / control drum, total reactivity / point reactor module and power management system.

[0089] The composition and functions of each module are as follows:

[0090] Reactor core: Taking the temperature of the evaporation section of the heat pipe as the boundary, calculate the core heat transfer and core temperature changes.

[0091] Heat pipe: Calculate the heat transfer and temperature change of the heat pipe using the hot end temperature of the thermoelectric power generation device as the boundary.

[0092] Thermoelectric power generation device: Using the radiation plate temperature as the boundary, the heat transfer and parameters such as voltage, current, and electric power of the thermoelectric device are calculated according to the load of the power management system.

[0093] Radiator: Calculate the temperature change of the radiator and the amount of waste heat radiated.

[0094] PID controller / control drum: drives the control drum appropriately based on the reference electrical power, introducing reactivity.

[0095] Total Reactivity / Point Reactor Module: Calculates the temperature negative reactivity generated by the control drum reactivity of the PID controller / control drum and the core temperature, calculates the core thermal power change through the point reactor neutron kinetic equation and transfers the thermal power to the reactor core.

[0096] Power management system: Using the thermoelectric output parameters of the space heat pipe stack power supply as input, it conducts power control simulation, calculates parameters such as charging and discharging power, load output power, and feeds back signals such as load resistance changes to the power calculation of the thermoelectric power generation device.

[0097] The modules are coupled and calculated to obtain the thermoelectric output characteristic parameters of the space heat pipe stack power supply through data transmission such as boundary conditions.

[0098] As shown in Table 1, the calculation verification related to the present invention is mainly verified by case studies using three-dimensional high-fidelity CFD (computational fluid dynamics) software. CFD software uses a three-dimensional high-precision model with high theoretical calculation accuracy. It is a commonly used calculation method in the field of mass transfer and heat transfer, but its calculation efficiency is low, and the calculation time usually takes several days or even dozens of days. The calculation method adopted by the present invention has the characteristics of fast calculation speed and high calculation accuracy. Key parameters such as temperature, voltage, and current were selected for comparison. Among them, the relative deviation of the average core temperature calculated by the two methods was 0.29%, and the relative deviation of the load current was 4.49%, which is lower than the 5% error range commonly used in research work. It can be considered that this method has high calculation accuracy and can be applied to the calculation of thermoelectric output characteristics of space heat pipe reactor power supplies, providing technical support for the design of power management systems for nuclear-powered spacecraft.

[0099] Table 1 Case verification

[0100]

[0101] Example 2: Figure 5 As shown, in order to achieve the above-mentioned purpose, based on the first embodiment, the present invention discloses a device for calculating the thermoelectric output characteristics of a space heat pipe stack power supply, comprising:

[0102] A parameter processing module 11 is configured to obtain power system design parameters and the power requirements of a nuclear-powered spacecraft in a deep space exploration mission, input the power system design parameters into a pre-established space heat pipe reactor power system model, and obtain processed power system design parameters based on the power requirements of the nuclear-powered spacecraft in the deep space exploration mission;

[0103] The parameter updating module 12 is used to receive the bus voltage reference value of the power supply system, determine the series-parallel mode based on the bus voltage reference value of the power supply system, update and calculate the processed power supply system design parameters according to the series-parallel mode, and obtain the thermoelectric parameters of the space heat pipe stack power supply under the load resistance.

[0104] Based on the same inventive concept, the present invention also provides a computer device, which includes: one or more processors and a memory for storing one or more computer programs; the program includes program instructions, and the processor is used to execute the program instructions stored in the memory. The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is used to implement one or more instructions, specifically for loading and executing one or more instructions in a computer storage medium to implement the above method.

[0105] It should be further explained that, based on the same inventive concept, the present invention also provides a computer storage medium having a computer program stored thereon, which, when executed by a processor, performs the above-described method. The storage medium may be any combination of one or more computer-readable media. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electrical, magnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection having one or more conductors, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0106] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0107] The above shows and describes the basic principles, main features and advantages of the present disclosure. Those skilled in the art should understand that the present disclosure is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present disclosure. Various changes and improvements may be made to the present disclosure without departing from the spirit and scope of the present disclosure, and such changes and improvements shall fall within the scope of the present disclosure.

Claims

1. A method for calculating the thermoelectric output characteristics of a space heat pipe stack power supply, characterized in that: The method comprises the following steps: Obtaining power system design parameters and the power requirements of nuclear-powered spacecraft in deep space exploration missions, inputting the power system design parameters into a pre-established space heat pipe reactor power system model, and obtaining processed power system design parameters based on the power requirements of nuclear-powered spacecraft in deep space exploration missions; receiving a bus voltage reference value of the power system, determining a series-parallel connection mode based on the bus voltage reference value of the power system, updating and calculating the processed power system design parameters according to the series-parallel connection mode, and obtaining thermoelectric parameters of the space heat pipe stack power supply under the load resistance; After the thermoelectric parameters of the space heat pipe stack power supply under the load resistance value are calculated, convergence judgment needs to be performed, and the relative difference of the thermoelectric parameters of the space heat pipe stack power supply under two different load resistance values ​​is calculated to determine whether the relative difference meets the convergence condition. If the convergence condition is not met, the thermoelectric parameters of the space heat pipe stack power supply under the load resistance value calculated later are used as input conditions for recalculation, and the calculation is terminated when the convergence condition is met. The thermoelectric parameters of the space heat pipe stack power supply under the load resistance value obtained by the calculation when the convergence condition is met are used as the final thermoelectric parameters of the space heat pipe stack power supply under the load resistance value; The calculation of the thermoelectric parameters of the space heat pipe stack power supply under the load resistance value includes: The core thermal power is calculated using a point reactor neutron kinetic model, and the lumped parameter method is used to solve the heat conduction equation to obtain the average temperature of the reactor core. The thermal resistance network method is used to simulate the heat transfer effect of the heat pipe to obtain the temperature of each area in the heat pipe. The electromotive force of the thermoelectric device is solved based on the Seebeck effect, as well as the current, voltage and electric power generated when the thermoelectric power generation device forms a closed loop with the load, and the radiation waste heat of the radiator is calculated.

2. The method for calculating the thermoelectric output characteristics of a space heat pipe stack power supply according to claim 1, characterized in that: The method of calculating the core thermal power using a point reactor neutron kinetic model includes: In the formula is the neutron flux density, for t Responsiveness of the moment, β is the total fraction of delayed neutrons, β i For the i is the share of delayed neutrons in the group, Λ is the neutron generation time, λ i It is i The delayed neutron decay constant, C i It is i Group delayed neutron precursor concentration; The method of solving the heat conduction equation using the lumped parameter method to obtain the average temperature of the reactor core includes: in, ρ F is the fuel density, c F is the specific heat capacity of the fuel, V F is the fuel volume, T F is the average fuel temperature, T HPe is the average temperature of the evaporation section of the heat pipe, R F is the heat transfer resistance between the core fuel and the evaporation section of the heat pipe, q F is the heat release rate of the fuel.

3. The method for calculating the thermoelectric output characteristics of a space heat pipe stack power supply according to claim 1, characterized in that: The thermal resistance network method is used to simulate the heat transfer effect of the heat pipe to obtain the temperature of each area in the heat pipe, including: The energy conservation equation is used to calculate the transient operating characteristics of a single thermal resistor and obtain the temperature of each area in the heat pipe. The energy conservation equation group is expressed as: in, ρ i For the i The density of the thermal resistance, A i For the i The cross-sectional area of ​​the thermal resistance, δ i For the i The thickness of the thermal resistance, c p,i For the i The specific heat capacity of a thermal resistance, T i For the i The center temperature of the thermal resistor, T i,1 and T i,2 Respectively i The front and rear temperatures of a thermal resistor, λ i It is i The thermal conductivity of the thermal resistance, α i It is i Thermal diffusivity of thermal resistance, Q i,1 and Q i,2 They are i The heat transferred between the front and back ends of a thermal resistor; The method for solving the electromotive force E of the thermoelectric device based on the Seebeck effect includes: in, a i It is i The Seebeck coefficient of the thermoelectric material used in the temperature difference device is E i It is i The electromotive force of a thermoelectric device, Δ T i is the temperature difference across the thermocouple.

4. The method for calculating the thermoelectric output characteristics of a space heat pipe stack power supply according to claim 3, characterized in that: The calculation process of the current, voltage and electric power generated after the thermoelectric power generation device and the load form a closed loop includes: Where, R i is the internal resistance of the thermoelectric power generation device, R c is the contact resistance between the thermoelectric generator and the conductor, R load is the load resistance, I is the current, U is the voltage, P For electrical power.

5. The method for calculating the thermoelectric output characteristics of a space heat pipe stack power supply according to claim 4, characterized in that: The radiator radiates waste heat Q rad Calculation, Q rad The size of is related to the fourth power of the radiation panel temperature and the fourth power of the space background radiation temperature, including: in, ε is the surface emissivity of the radiation panel, σ is the Stefan-Boltzmann constant, A is the surface area of ​​the radiation panel, T rad is the radiation panel temperature, T space is the space background radiation temperature, and the superscript 4 represents the fourth power of the temperature.

6. A device for calculating the thermoelectric output characteristics of a space heat pipe stack power supply, which adopts the method for calculating the thermoelectric output characteristics of a space heat pipe stack power supply according to any one of claims 1 to 5, characterized in that: include: a parameter processing module for obtaining power system design parameters and the power requirements of nuclear-powered spacecraft in deep space exploration missions, inputting the power system design parameters into a pre-established space heat pipe reactor power system model, and obtaining processed power system design parameters based on the power requirements of nuclear-powered spacecraft in deep space exploration missions; The parameter update module is used to receive the bus voltage reference value of the power supply system, determine the series-parallel mode based on the bus voltage reference value of the power supply system, update and calculate the processed power supply system design parameters according to the series-parallel mode, and obtain the thermoelectric parameters of the space heat pipe stack power supply under the load resistance.

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