NASA's Evolutionary Xenon Thruster (NEXT) Prototype Model 1R (PM1R) Ion Thruster and Propellant Management System Wear Test Results

Abstract The results of the NEXT wear test are presented. This test was conducted with a 36-cm ion engine (designated PM1R) and an engineering model propellant management system. The thruster operated with beam extraction for a total of 1680 hr and processed 30.5 kg of xenon during the wear test, which included performance testing and some operation with an engineering model power processing unit. A total of 1312 hr was accumulated at full power, 277 hr at low power, and the remainder was at intermediate throttle levels . Overall ion engine performance, which includes thrust, thruster input power, specific impulse, and thrust efficiency, was steady with no indications of performance degradation. The propellant management system performed without incident during the wear test. The ion engine and propellant management system were also inspected following the test with no indication of anomalous hardware degradation from operation. Nomenclature DACS Data Acquisition and Control System DCA Discharge Cathode Assembly DCIU Digital Control Interface Unit EM Engineering Model FCD Flow Control Device GRC NASA Glenn Research Center HPA High Pressure Assembly JPL NASA Jet Propulsion Laboratory LDT Long Duration Test LPA Low Pressure Assembly NCA Neutralizer Cathode Assembly NEXT NASA’s Evolutionary Xenon Thruster NSTAR NASA Solar Electric Propulsion Technology Application Readiness PFCV Proportional Flow Control Valve PM Prototype Model PMS Propellant Management System PPU Power Processing Unit TRL Technology Readiness Level VF5 Vacuum Facility 5 XFSE Xenon Feed System Equipment