空间热光伏发电技术进展与展望

Research status and prospect of space thermophotovoltaic power generation technology

空间同位素电源是通过热电转换技术将衰变热能转换为电能的空间电源装置,广泛应用于深空探测任务中太阳能电池无法使用的任务场景,其热电转换方式包括温差、热光伏等静态转换方式以及斯特林、布雷顿等动态转换方式。空间同位素电源普遍使用钚238核源,其制备生产困难,价格高昂,在全球范围内产能受限,同时,长周期的深空探测任务对同位素电源寿命也提出较高要求,因此热电转换效率高、易于实现长寿命的空间热光伏发电技术成为开展深空探测任务的优选技术路线。近年来,近场热光伏、基于光谱调控的热光伏技术是研究重点,结构热控、辐射器、滤光器、电池晶元等关键器件的理论研究与技术验证也取得了显著的进展。对热光伏空间同位素电源技术方案、关键器件研究情况进行了综述,从电源系统总体设计的角度对各器件的发展现状与未来技术的发展重点方向进行了研判,可为进一步推动热光伏同位素电源系统的工程化研制提供参考。

Space radioisotope power is a space power device that converts nuclear decay thermal energy into electrical energy through thermoelectric conversion technology,and is widely used in deep space exploration missions.Space isotope power commonly uses plutonium 238 as nuclear sources.The preparation and production of plutonium 238 are difficult and expensive,resulting in worldwide limited production capacity.Meanwhile,long-term deep space exploration missions propose high requirements for the lifespan of isotopic power.Space thermal photovoltaic radioisotope power with high thermoelectric conversion efficiency and long lifespan has become the preferred technical route for deep space exploration missions.NASA has demonstrated a RTPV prototype with a conversion efficiency greater than 20%.In recent years,near-field thermal photovoltaic and spectral-regulation thermal photovoltaic technology have become the hotspot.Significant progress has also been made in the theoretical research and technical verification of critical devices such as emitters,optical filters,and photovoltaic cells.In this paper,the research progress of RTPV system designs and relevant key devices is reviewed.Based on the system level requirements,the development status of each device is stuaied and the future trend is suggested.This paper provides a reference for promoting the engineering development of thermophotovoltaic radioisotope power supply system in the future.