To meet the application requirements of continuous variable thrust capability and high-resolution characteristics for ion thrusters in drag-free flight missions of gravity gradient measurement satellites and precise orbit maintenance missions of near-Earth high-resolution observation satellites, technical research and application verification were conducted on a high-resolution wide-range variable thrust ion thruster. Leveraging the weak coupling and relative independence between the two critical physical processes of plasma discharge and ion beam extraction in Kaufman-type ion thrusters, a wide-range variable thrust ion thruster technical scheme with a divergent magnetic field configuration was proposed. Key technical investigations included wide-range discharge stability in the discharge chamber, a concave spherical ion optical system configuration design balancing wide-temperature-range ignition and high-density extraction requirements, and hollow cathode current emission continuity design. Based on this, the design optimization and ground-based performance evaluation of a 10cm-aperture high-resolution wide-range continuously variable thrust ion thruster were completed, achieving on-orbit flight application in 2023. Satellite on-orbit test results demonstrate that the 10cm-aperture thruster achieves thrust regulation of 0.99–20.05 mN within a power range of 98.5–585 W, with specific impulse maintained at 410–3100 s, consistent with ground test results. The thrust response rate reaches approximately 3 mN/s, and thrust resolution exceeds 15 μN, outperforming ground test metrics. Compared to traditional chemical propulsion systems for satellite orbit control, the thruster enables a two-order-of-magnitude improvement in orbit maintenance accuracy, effectively ensuring the implementation of the satellite's on-orbit engineering missions.
Hu et al. (Wed,) studied this question.