The power system of a free piston Stirling generator (FPSG) based on potassium heat pipes has been developed in this paper. Thanks to the advantages of long life, high reliability, and high overall thermal efficiency, the FPSG is a promising candidate for nuclear energy, especially in space exploration. In this paper, the recent progress of FPSG based on nuclear reactor for space use was briefly reviewed. A novel FPSG weighted only 4.2 kg was designed, and one dimensional thermodynamic modeling of the FPSG using Sage software was performed to estimate its performance. The experiment results indicated that this FPSG could provide 142.4 W at a thermal-to-electric efficiency of nearly 17.4%. Besides, the power system integrated with four FPSGs and potassium heat pipes was performed and the single machine failure test was conducted. The results show that this system could provide an electrical power of 300 W at an overall thermal efficiency of 7.3%. Thus, it is concluded that this power system is feasible and will have a great prospect for future applications.

中文翻译：

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基于钾热管的自由活塞斯特林发电机的空间动力系统

本文开发了一种基于钾热管的自由活塞斯特林发电机（FPSG）的动力系统。由于寿命长，可靠性高和整体热效率高，FPSG是核能的有希望的候选者，特别是在太空探索中。在本文中，简要回顾了基于核反应堆用于太空用途的FPSG的最新进展。设计了重量仅为4.2 kg的新型FPSG，并使用Sage软件对FPSG进行了一维热力学建模，以评估其性能。实验结果表明，该FPSG可以提供142.4 W的功率，热电效率接近17.4％。此外，还执行了将四个FPSG和钾热管集成在一起的电源系统，并进行了单机故障测试。结果表明，该系统可提供300 W的电能，总热效率为7.3％。因此，可以得出结论，该电力系统是可行的，并将在未来的应用中具有广阔的前景。