微型射频离子推力器自中和引出特性研究

Based on the self-developed miniature RF ion thruster BHRIT-4，the research on characteris⁃ tics of neutralizer-free extraction has been carried out，including extraction beam profile，external circuit and beam ion energy. The research results indicate that in the neutralizer-free extraction mode，the brightness of the neutralizer-free extraction beam region is high and there is a strong electron excitation reaction in this region，the average float potential in the plume region is maintained at 1.19 V. The RF self-bias voltage is not positively cor⁃ related with the output power，and there is an optimal output power value to achieve maximum RF self-bias volt⁃ age，with a maximum value exceeding 300 V. The ion energy distribution function（IEDF）of the neutralizer-free extraction beam does not follow the Gaussian distribution and has a large broadening，and there is bimodal signal under some conditions.