摘要
Hollow cathodes are widely used as electron sources and neutralizers in ion and Hall electric propulsion.Special applications such as commercial aerospace and gravitational wave detection require hollow cathodes with a very wide discharge current range.In this paper,a heater is used to compensate for the temperature drop of the emitter at low current.The self-sustained current can be extended from 0.6 to 0.1 A with a small discharge oscillation and ion energy when the flow rate is constant.This is also beneficial for long-life operation.However,when the discharge current is high(>1 A),heating can cause discharge oscillation,discharge voltage and ion energy to increase,f urther,combined with a rapid decline of pressure inside the cathode and an increase in the temperature in the cathode orifice plate,electron emission in die orifice and outside the orifice increases and the plasma density in the orifice decreases.This leads to a change in the cathode discharge mode.
作者
扈延林
宁中喜
刘晓宇
初彦峰
毛威
沈岩
朱悉铭
Yanlin HU;Zhongxi NING;Xiaoyu LIU;Yanfeng CHU;Wei MAO;Yan SHEN;Ximing ZHU(Beijing Institute of Control Engineering,Beijing 100080,People's Republic of China;Plasma Propulsion Lab,Institute of Advanced Power,Harbin Institute of Technology,Harbin 150001,People's Republic of China)