(AASERT-97) Development of a Field Emitter Cathode for Low-Power Hall Thrusters
Abstract
Fuel-efficient electric propulsion (EP) systems such as the Closed-Drift Hall thruster (CDT) can greatly enhance the capability of small satellites by reducing spacecraft propellant mass while increasing sensor payload and Deltav. However, a major stumbling block to the development of low-power (</- 100 W) CDTs is the absence of a suitable cathode. Conventional 6.4-mm hollow cathodes consume 20 W of power and 5 sccm of propellant, which is more than the total propellant flow rate of a 100-W CDT. Smaller hollow cathodes (e.g., 3.2-mm) are in development with the challenging goal of consuming 5 W of power. However, the minimum propellant flow rate of these cathodes is unlikely to dip much below 1 sccm. Our approach for providing electron emission for low-power CDTs is to use field emitter array cathodes (FEACs) as a replacement for hollow cathodes. AASERT funds were secured to support one student in a three-year program to investigate the use of FEAC technology with CDTs. The current-voltage characteristics and lifetime of several baseline cathode designs were evaluated over a wide range of pressures (10(exp -10) to 10(exp -6) Torr range in an ultra high vacuum FEAC test facility. FEAC performance models were also developed and compared with experimental results.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 25, 2001
- Accession Number
- ADA393628
Entities
People
- A. D. Gallimore
- C. M. Marrese
Organizations
- University of Michigan