Effects of magnetic field configurations on the minimized ECR ion thrusters for micro-Newton and wide-range operations

Abstract

Space-based gravitational wave detection missions require precise thrusts over a wide-range of 1–100 μN. In this study, the axial ring-cusp magnetic field configuration is used to design a miniature electron cyclotron resonance ion thruster with a radius of 5 mm. Two typical configurations, i.e., open-type and closed-type, are compared in terms of electron density, electron temperature, and thrust for micro-Newton and wide-range operations. The results show that the open-type achieves high performances owing to the high efficiency of absorption of input microwave power. The lower limit of the mass flow rate in the electron cyclotron resonance (ECR) discharge is expanded to a very low value of 3 × 10−2 sccm to achieve 1 μN in the open-type. The thrust in the open-type could be tuned in a wide-range of 1–119 μN, meeting the requirement.