Thrust measurements of the RIT-10 thruster with a new type of thrust balance

Abstract

To study electric propulsion devices, accurate long-time measurements of the low thrust forces are necessary. For this purpose, a new, lightweight thrust balance has been established to be used at DLR’s STG-ET facility – the DLR Electric Propulsion Thrust Balance (DEPB). To evaluate the performance of this thrust balance, it has been operated to perform measurements of the well-studied RIT 10 gridded-ion thruster. The new thrust balance and its performance are demonstrated and a first estimate on accuracy and long-term stability shall be given. While the setup has been fully manufactured and calibrated, a final test using an electric thruster is still necessary. To study the behavior of the thrust balance, the RIT-10 thruster is operated for extended intervals on the DEPB thrust balance. The long-term stability in terms of thermal drift, effects of the fluid and electric interface and effects of the vacuum and plasma environment onto the thrust balance are studied.