IMPROVEMENT OF HALL THRUSTER PERFORMANCE

利用自行开发的二维有限元磁分析程序，对影响霍尔推力器性能的磁路进行了设计。在加速通道的中心位置设置了一个螺线管线圈，以使其具有较强的径向磁场。基于上述电路设计，设计并制作了某推力器的加速通道。此外，还订购和组装了用于等离子体产生、离子加速和中和的电源。2.5m长的腔室和10，000 l/s的泵送系统。我们获得了稳定的电弧放电以及正常的等离子体产生和离子束提取。在输入功率增加到1.5kW时，进行了推力测量，以评估推力器的性能。为了获得离子束流的加速效率，还测量了离子束流，并研究了通道几何形状、场强和工作条件对离子束流的影响。采用空心阴极，当以氙气为推进剂时，获得了34%的最大推力效率。

A magnetic circuit that largely influences Hall thruster performance was designed by using two-dimensional FEM magnetic analysis code which was developed previously. A solenoidal coil was positioned at the center of acceleration channel in order to have high radial magnetic fields applied on it.Based on the above circuit design, the acceleration channel of a thruster was designed and fabricated. In addition, power supplies for plasma production, ion acceleration, and neutralization were ordered and assembled.The thruster was operated in the vacuum system which consists of a 0.8 m diam. and 2.5 m long chamber and 10,000 1/s pumping system. We obtained stable arc discharge as well as normal plasma production and ion beam extraction. Also, discharge voltage-current characteristics were examined and show a general tendency for this kind of thruster.Increasing an input power up to 1.5kW, thrust measurement was done to estimate thruster performance. Ion beam current was also measured to obtain acceleration efficiency and to investigate the effect of channel geometry, field strength, and operating conditions on it.A hollow cathode was installed on the thruster in place of a filament cathode. With the hollow cathode, a maximum thrust efficiency of 34 % was obtained when xenon gas was used as the propellant.