Electromagnetic Emissions from an Engineering Model BHT-200 Thruster
Abstract
Radiated electric fields were measured from a BHT-200 Hall thruster from 10 kHz to 18 GHz following MIL-STD 461E (RE102) specifications. The thruster, operated by a laboratory power supply, was located in a fiberglass vacuum tank that was enclosed in a shielded semi-anechoic room. The measurements were made for discharge potentials of 225, 250, 275, and 300 volts and anode flow rates of 0.80 0.90, 0.94, and 1.0 mg/s (150-240 W discharge power) as well as for several cathode flow rates. For all flow rates and discharge voltages, emission exceeded MIL-STD 461E limits between 10 kHz to 200 MHz. However, for the anticipated thruster operating point (250 V, 0.94 mg/s), electromagnetic emissions remained below MIL-STD 461E limits between 350 MHz and 18 GHz. Generally, electromagnetic emission decreased with increasing anode flow rate below 500 kHz and between 15-30 MHz but increased with anode flow rate between 1-5 MHz. Above 30 MHz, there was no variation of emission with anode flow rate. When the thruster operated at 250 V and 0.94 mg/s anode flow rate, emission decreased with increasing cathode flow rate below 500 kHz. There was no significant variation of emission with discharge voltage above 500 kHz. There was no appreciable difference between spectra taken with the high frequency blocking filter located inside a shielding box next to the thruster and spectra taken with the filter located outside the vacuum chamber. Spectra of the anode current oscillations recorded between 1 kHz and 50 MHz were similar to the radiated spectra and show minimal variation with cathode flow rate.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2001
- Accession Number
- ADA396844
Entities
People
- B. Pote
- E. J. Beiting
- J. E. Pollard
Organizations
- The Aerospace Corporation