Update of the design of the AMTEC converter for use in AMTEC Radioisotope Power Systems

An AMTEC converter is under development for use in the AMTEC Radioisotope Power System (ARPS) program. The ARPS program is a collaboration between DOE and NASA to develop the next generation of heat to electrical power conversion systems for use in deep space probes. The prime system contractor is Lockheed Martin Corporation, with Advanced Modular Power Systems, Inc. (AMPS) responsible for the development of the AMTEC converter. This paper updates the design information presented in earlier papers. Changes to the early BASE tube design have led to improved power density that has surpassed performance targets. An improved artery/evaporator is now capable of operating at 50 °C over nominal temperatures and enabling accelerated life testing of converters. This paper also describes the improvement of peak power that each converter design iteration has made and presents the latest converter test data showing the match to the AMPS analytical model. Life test data of a converter that has operated for over 10,000 hours is plotted and a brief overview of the future direction of the AMTEC radioisotope power converter is given.