Performance and High-Speed Characterization of a 100-kW Nested Hall Thruster

Abstract

The performance of a three-channel, 100-kW nested Hall thruster was evaluated on xenon propellant for total powers up to 102 kW. The thruster demonstrated stable operation in all seven available channel combinations at discharge voltages from 300 to 500 V and three different current densities. The resulting test matrix contained forty-six unique conditions ranging from 5 to 102 kW total power and 16 to 247 A discharge current. At each operating condition, thrust, specific impulse, and efficiency were characterized. All seven channel combinations showed similar performance at a given discharge voltage and current density. The largest thrust recorded was $5.4\pm 0.1\mathrm{N}$ at $99\mathrm{kW}/400\mathrm{V}$ discharge voltage. Total efficiency and specific impulse ranged from 0.54 to $0.67\pm 0.03$ and from 1800 to 2650 s $\pm 60$ s, respectively. Discharge current oscillations were also characterized with peak-to-peak values and with high-speed camera analysis, which provide insight into how the discharge channels oscillate and how those oscillations are affected by the presence of other operating channels. These results are discussed in the context of differences between single- and multichannel operation, as are the implications for the general viability of nested Hall thruster technology for future mission applications.