In-Space Propulsion (Electric/Magnetic)

High power electric propulsion (e.g., ion, Hall, magnetoplasmadynamic (MPD) thrusters, pulsed inductive thrusters (PIT), Variable Specific Impulse Magnetoplasma Rocket (VASIMR) and other plasma thrusters) is an essential technology for orbit insertion and planetary transfers of future nuclear and non-nuclear human exploration spacecraft. This subtopic solicits innovative component technologies related to high power electric propulsion systems for these applications. Innovations may increase system efficiency, increase system and/or component life, increase system and/or component durability, reduce system and/or component mass, reduce system complexity, reduce development issues, or provide other definable benefits. For this subtopic, high power electric propulsion is defined as systems with power levels of 100 kW to several megawatts and higher. Desired specific impulses range from a value of 2000 s for Earth-orbit transfers to over 6000 s for planetary missions. System efficiencies in excess of 50% are desired. System lifetimes commensurate with mission requirements (typically 10,000+ hours of operation) are desired. Component technologies for high power applications of particular interest are those that can be commercially spun-off or can also be applied to lower power electric propulsion devices and applications. Proposed high power electric thruster component technologies must have near-term applications that can be pursued in a Phase-II effort. Examples of component technologies of interest include but are not limited to:

• High voltage propellant isolators (10 kV);
  
• Long-life, high current cathodes (100,000 hours);
  
• Innovative plasma neutralization concepts;
  
• Metal propellant management systems and components;
  
• Cathodes for metal propellants;
  
• Low mass, high efficiency power electronics for RF discharges;
  
• Low voltage, high temperature wire for electromagnets;
  
• High temperature permanent magnets and/or electromagnets;
  
• Application of advanced materials for electrodes and wiring;
  
• Highly accurate propellant control devices/schemes;
  
• Miniature propellant flow meters;
  
• Lightweight, long-life storage systems for krypton and/or hydrogen;
  
• Fast acting, very long life valves and switches for pulsed inductive thrusters;
  
• Superconducting magnets;
  
• Lightweight thrust vector control for high power thrusters;
  
• High fidelity methods of determining the thrust of ion, Hall, MPD, VASIMR engines without using conventional thrust-stands; and
  
• Heat transfer and rejection components for high temperature and cryogenic regimes (applications of advanced materials, heat pipes, etc.).