µe Magnetic Moment, J/T

The performance of a low-power cylindrical Hall thruster, which lends itself more readily to miniaturization and low-power operation than conventional (annular) Hall thrusters, was measured using a newly developed thrust stand capable of measuring thrust levels ranging from 1-1000 mN. This test provided an opportunity to demonstrate the stand’s mN-level thrust measurement capability. Several new techniques are built into the thrust stand for the purpose of reducing drift in the thrust stand pendulum arm ‘zero’-position. An auto-leveling system with feedback control maintains the position of the stand while the temperature is controlled using a constant temperature output water chiller. In addition, the effects of wire heating and deformation are minimized by conducting current onto the pendulum arm through pools of liquid gallium. These accuracy-enhancing measures enabled measurements of cylindrical Hall thruster performance over a power range of 90-185 W. The measured thrust ranged from 3-6 mN, with anode efficiencies and specific impulses spanning 20-27 % and 1100-1650 s, respectively. While showing quantitative agreement with literature data obtained using the same thruster, these measurements possessed a smaller uncertainty due to the stability of the thrust stand arm ‘zero’-position