Electron Cyclotron Resonance Thruster Diagnostics & Performance Analysis

Abstract

This thesis describes the process by which the performance of an electrodeless, coaxial electron cyclotronresonance thruster is evaluated. Using a thrust stand, retarding potential analyzer, and Faraday probe, the performance of the thruster under various permutations of steady state and pulsed operating regimes was analyzed in terms of thrust performance, plasma properties, including ion energy distribution functions, pulse current contour profiles, and thruster plume characteristics, including plume divergence and mass utilization efficiency. Performance for each permutation of pulsed operating regime is evaluated and compared quantitatively using a series of analysis scripts to isolate the thruster’s behavior at different time slices throughout a pulse. Operating in a high maximum power pulse regime, with a low average power, could offer a way to leverage improvements in ionization efficiency and mass utilization fraction associated with operating at a high power without the large spacecraft power capacity associated with continuously operating at this high power. These results demonstrate that pulsed operation does not appear to manifest a significant degradation in performance for comparable continuous operational settings relative to average power. However, in comparing between the two pulse regimes assessed, longer duty cycles did correlate with increased overall performance.