电负性气体等离子体推力器研究进展

目前广泛应用的电推力器中，大多采用加速单一正离子的方式来获得推力和相应比冲。该加速方式需要增设中和器，对喷射出的正离子进行中和以保持羽流电中性，否则将导致航天器自充电，对其通信和电子器件造成损害，并减弱加速场。为了简化系统结构，延长推力器寿命，提出了一种能够交替加速正、负离子来获得推力的电负性气体等离子体推力器。分析了该推力器的工作原理和加速过程，指明了包括电负性气体种类选取、电子过滤装置设计要求、如何施加周期性栅极偏置电压加速正、负离子以及合理诊断离子数密度等关键技术，为后续研究工作提供了参考。

The development of research on plasma propulsion with electronegative gases

In the wide application of electric thrusters, most of them work on the principle of accelerating positive ions only to provide moderate thrust and high specific impulse. The ion beam current and space charge need to be compensated by the additional neutralization systems in the downstream space to avoid self charging of the satellites, damage of the communication equipment and electronic devices as well as cancellation of the acceleration field. In order to simplify the system structure and prolong the life of thrusters, a space electric propulsion system where both positive and negative ions can be accelerated alternately to obtain the thrust was proposed. The background and present situation of the development of plasma propulsion with electronegative gases (PEGASES) were introduced. The way to generate and accelerate positive and negative ions simultaneously was also discussed, including how to choose electronegative gases, magnetic field filter design requirements, the applied bias voltage way for grids in which the positive and negative ions could be accelerated alternately and periodically, as well as the density diagnostics of the plume.