for robotic science missions...presented by: dave anderson | planetary spacecraft technology project...

Presented by: Dave Anderson | Planetary Spacecraft Technology Project | NASA Glenn Research Center | David.J.Anderson@nasa.gov | (216) 433-5356

www.nasa.gov

National Aeronautics andSpace AdministationElectric Proplusion for Science Missions

* Small Business Innovation Research* NEXT- C (Commercial)

Thruster

Gimbal

XenonTank XFCM

PPUSingle String

GimbalVACCOXFCM

CPE Brassboard PPU

Lt WtPropellant

Tank BPT-4000 HV

HIVHAC EDU2

Performance Characteristics of HIVHAC vs. State of the Art Hall Characteristic HIVHAC BPT-4000 (XR-5)Input Power, kW 0.3-3.9 0.3-4.5 Specific Impulse, sec 860-2700 710-2100Thrust, mN 20-207 22-260Efficiency 0.32-0.62 0.25-0.58Propellant Throughput, kg >300 450Throttle Ratio 12:1 15:1Operating Voltage, V 200-700 150-400

For Robotic Science Missions• Discovery Class• Near Term New Frontiers• Flagship Class• Mars Exploration• Outerplanet Missions• Small Bodies Missions

For Robotic Science Missions• Discovery Class – Double asteroid rendezvous – High-AU Comet rendezvous – Near-Earth asteroid sample return – Solar Electric Propulsion missions• New Frontiers – Double near-Earth asteroid sample – Comet surface sample return• Mars sample return

NEXT Accomplishments• Successful eight year long duration test – 918 kg of Xenon throughput – 51,180 hours of operation – 35.5 mN-sec. total impulse• Wear test inspection underway• Intensive Spacecraft Interaction Diagnostics Program

NEXT-C* for 2014 Discovery AO• Government furnished equipment – 2–NEXT flight thrusters – 2–Power Processing Units

HIVHAC Accomplishments• Integrated component tests completed: – HIVHAC Engineering Demonstration Unit (EDU) thruster – Colorado Power Electronics brassboard PPU – VACCO Xenon Flow Controlled Module (XFCM)• SBIR* Technology Maturation Plan Proposal Selected – Colorado Power Electronics Power Processing Unit (PPU)–Qualification Model (QM)• HIVHAC System/Components Commercialization Technology Interchange Meeting/Workshop (TIM) planned for fall 2014

PowerProcessingUnit

Thruster

Gimbal

LPA

PPUSingle String

Gimbal

DCIU

HPA

Solar Arrays

Spacecraft Controller

NEXT ThrusterInteraction Test

NEXT Thruster Test

Digital Control Interface Unit Simulator(Aerojet)

Low Pressure AssemblyHigh Pressure Assembly

PropellantMORE Science

for LESSNEXT:High Voltage Hall AcceleratorHIVHAC:

NASA's Evolutionary Xenon ThrusterChemical

ELECTRIC Propulsionfor the COSTof

Performance Characteristics of NEXTThruster Input power, kW 0.55-6.9Thrust,mN 25-237Specific Impulse, sec 4,190Efficiency > 70%Propellant Throughput, kg 918Power Processing UnitEfficiency (over throttle range) 89-95%

NEXT Element MassesThruster, kg 12.8 PPU, kg 34.5 HPA, kg 1.9 kgLPA, kg 3.1 kgGimbal,kg 6.0 kg

System ReadinessSystem Validation üMulti-thruster system testing and modeling – Complete üSingle-string system integration test – CompletePrototype Model (PM) Thruster üPerformance Acceptance Testing – Complete üQual-Level Environmental Test – CompleteEM Propellant Management System Flight-like Low Pressure (LPA) and High Pressure Assemblies (HPA) completed full subsystem validation testing üPerformance Acceptance Testing – Complete üQual-Level Environmental Test – CompleteEngineering Model (EM) PPU • The EM PPU tests uncovered need for further refinements • Assessed verification gaps and PPU design weaknesses that needed addressing • Completed EEE parts and high voltage component assessments reviewed and updated PPU requirements • Created Safety and Mission Assurance Plan for future PPU development • Existing PPU reassembled for use as testbed to support design evaluation • Proceeding into a second generation PPU design

System ReadinessHIVHAC EDU2 Thruster üPerformance Acceptance Testing – Complete üVibrationTesting – Complete üPlume characterization and Mechanism Actuation – CompleteInitiated Study of Magnetically Shielded HIVHACVACCO Xenon Flow Controlled Module üAll Qual-Level Test ing– Complete

Integration Test of System Components üMultiple integrated component tests of HIVHAC EDU thruster, CPE brassboard PPU, VACCO XFCM– Complete • Multiple Thruster (HIVHAC EDU/XR-5/SPT-140) operability tests with CPE QM PPU and Vacco XFCM planned

XenonTank

Lt WtPropellant

Tank