Plasma Diagnostic and Performance of a Permanent Magnet Hall Thruster
Jose Leonardo Ferreira, Joao Henrique Campos De Souza, Israel Da Silveira Rego, Ivan Soares Ferreira
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12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France)Acknowledgements: We thank CNPq, CAPES and AEB for partial financial suport of the Plasma Thruster Project
Electric propulsion is now a sucessfull method for primary propulsion of deep space long duration missions and for geosyncronous satellite attitude control. Closed Drift Plasma Thruster, so called Hall Thruster or SPT (stationary plasma thruster) were primarily conceived in USSR (the ancient Soviet Union) and now it is been developed by space agencies, space research institutes and industries in several countries such as France, USA, Israel, Russian Federation and Brazil. In this work, we show plasma characteristics and performance of a Hall Thruster designed with an innovative concept which uses an array of permanent magnets, instead of an eletromagnet, to produce a radial magnetic field inside its cylindrical plasma drift channel. Within this new concept, we expect to develop a Hall Thruster within power consuption that will scale up to small and medium size satellites. A plasma density and temperature space profiles inside and outside the thruster channel will be shown. Space plasma potential, ion temperature measurements based on doppler broadenning of spectral lines and ion energy measurements are shown for different plasma production regimes. Experimentaly measured propulsion and power consumption will also be shown and compared with computational simulation models using the same plasma experimental conditions. In both cases the results are showing a thrust range between 40mN to 80mN which is close to the thrust levels obtained with a commercial SPT 100 using 30% less electrical power.
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