Constant-Power Performance and Plume Measurements of a Nested-Channel Hall-Effect Thruster

The X2 nested-channel Hall-effect thruster has been operated at constant discharge powers of 5 kW and 6 kW. Thrust measurements showed that improved performance over an extended range of specific impulse can be obtained by transitions between operating modes of the X2. The simultaneous operation of both channels provided the best performance at low specific impulse, where higher mass flow rates were necessary to maintain total power. The inner channel provided optimal performance at high specific impulse, while the outer channel was best suited for the intermediate-Isp region between the other two modes. Far-field RPA and E×B measurements were used to determine voltage utilization and charge utilization efficiencies during 6-kW operation. Discharge current measurements showed forms of interaction between discharge channels during simultaneous operation.