Abstract: Developing propulsion technology systems in the 50-to 300-kW per thruster range to meet the needs of a variety of long duration, deep-space mission applications beyond capabilities being developed for 40-kW SEP Tech Demo Mission. Three proposals were selected to develop and demonstrate NextSTEP advanced electric propulsion (EP) subsystems. The primary goal is during the third year, to demonstrate 100-hour of continuous, steady-state operation of propulsion subsystem at 100-kW in a relevant TR…