Inductive Coupling Discharge Characteristics of a 10-cm Dual-Stage 4-Grid Radiofrequency Ion Thruster

Abstract

In this study, the numerical simulations are used to simulate the discharge process of a 10-cm dual-stage 4-grid (DS4G) radiofrequency (RF) ion thruster, and the effects of RF coil turns, and electrical parameters on the key plasma parameters inside the discharge chamber are investigated. Thus, the optimal design parameters of the thruster are obtained. The RF plasma source has high inductive coupling discharge efficiency when the number of coil turns is six and the operational frequency is 2 MHz. The simulation results show that increasing the number of coil turns can effectively increase the plasma density inside the discharge chamber, and thus improve the efficiency of the inductive coupling discharge, and the operational frequency affects the characteristics of the inductively coupled discharge by influencing the depth of the plasma skinning layer. An experimental thruster demonstrated the 10-cm DS4G RF ion thruster can achieve super high specific impulse. The correctness of the simulation model is verified by the experiment results of the thruster, which will be useful for the optimal design of radio ion thruster or ion sources.