配电方式对Kaufman离子推力器性能的影响研究

目前Kaufman离子推力器主要有两种最具代表性的配电方式:屏栅极电源正端分别连接阳极电源正、负端的配电方式。为了研究配电方式对Kaufman离子推力器工作性能的影响,基于等离子体理论和推力器工作原理,分析两种主要配电方式下放电室电极电势及电流平衡关系,推导了放电室等离子体特性表达式,理论分析了配电方式对离子推力器多种性能参数的影响。结合兰州空间技术物理研究所自研的LIPS300离子推力器在两种配电方式下工作在3kW和5kW的性能试验,通过解析方法对离子推力器多种工作参数和性能参数进行分析,试验结果与理论分析结果具有良好的一致性。研究表明:采用屏栅极电源正端连接阳极电源负端的配电方式能够获得更大的推力和比冲,并能提高离子对栅极透明度,减少离子对屏栅极的溅射,从而提高栅极寿命,但束离子产生成本稍高。研究结果可为离子推力器配电方式的设计与优化提供依据。

Study on Effect of Power Distribution Modes on WorkingPerformance of Kaufman-Type Ion Thruster

Kaufman ion thruster mainly has two most representative distribution modes at present: the positive terminal of screen supply is connected with the positive or negative terminal end of anode supply. In order to study the effects of power distribution modes on performance of Kaufman-type ion thruster, the relationships between the electrode potential and current balance in the discharge chamber of two main power distribution modes were obtained and the expression of the plasma features was deduced and the effect on various performance parameters of ion thruster were analyzed theoretically. Combined with the performance tests of LIPS 300 ion thruster developed by Lanzhou Institute of Physics, which operated in 3kW and 5kW under two distribution modes, various working parameters and performance parameters of ion thruster were analyzed by analytical method. The experimental results were in good agreement with the theoretical analysis results. The study shows that the distribution mode with the positive terminal of screen supply connected with the negative end of anode supply can achieve higher thrust and specific impulse, improve the transparency of the grid, and reduce the sputtering rate of ions on the grid, thus improving the grid life, but the cost of beam ion generation is slightly higher. The study can provide approach for the design and optimization of power configuration for ion thruster.