Investigation of Low Discharge Voltage Hall Thruster Characteristics and Evaluation of Loss Mechanisms

摘要

During the early development stages of Hall thruster technology, plasma research and propulsion advancements centered primarily on 300 V, 1600 s specific impulse operation. Since the first thruster firing on a Soviet satellite in 1972, extensive investigations of the plasmadynamic discharge phenomena and operating characteristics progressed the propulsion concept to a high-level of performance suitable for a wide range of near-earth maneuvers and interplanetary missions. The expanded performance envelope is primarily a function of improvements in thruster lifetime, thermal margin, discharge stability, and power system capability. Advancements in the Hall thruster propulsion system have enabled a wider range of input parameters to the thruster, including the applied anode potential. Operation in the low discharge voltage regime is associated with a decline in total thruster efficiency. This dissertation is intended to investigate low voltage Hall thruster physics, identify dominant performance loss mechanisms, and determine the discharge characteristics that drive efficiency.