磁感应强度对10 cm连续变推力离子推力器性能的影响

Influences of Magnetic Induction Intensity on Performance of 10 cmContinuous Variable-thrust Ion Thruster

连续变推力离子推力器是重力梯度测量卫星在轨实现非重力阻尼连续、快速、高精度补偿的关键,其性能状态直接决定了卫星任务的成败。针对重力梯度测量卫星无拖曳飞行任务对10 cm连续变推力离子推力器的应用需求,分析了磁场对离子推力器实现宽范围、连续变推力的影响效应。在此基础上,研究了不同阳极供气流量下放电室内磁感应强度调节时整机输出推力的变化规律,获得了磁感应强度对推力器放电电压、工质利用率及放电损耗的影响作用关系。采用法拉第探针得到了磁感应强度与离子束流平直度间的映射关系。结果表明:10 cm连续变推力离子推力器输出推力随着磁感应强度的增加而不断增大,放电电压与磁感应强度之间呈现为非线性的二次多项式关系;随着磁感应强度在一定范围内的增大,工质利用率不断增加,放电损耗逐渐下降,离子束流平直度相应增大,但磁感应强度过大会导致放电室性能出现非预期性变化,等离子体出现失稳现象。研究为构建10 cm连续变推力离子电推进系统的推力控制算法及推力器整机磁路优化提供技术支持。

The continuous variable-thrust ion thruster is the key to realize compensation of the non-gravity dumping at high continuum speed with high accuracy for gravitational gradiometry satellites,and its performance directly influence the success of the satellite engineering mission.Aiming at the application requirement of drag-free mission of gravity gradient measurement satellite for 10 cm continuous variable-thrust ion thruster,the influence of magnetic induction intensity on wide range and continuous variable-thrust of ion thruster is analyzed.On this basis,the changing rule of the output thrust of the ion thruster was studied when the magnetic flux density was adjusted in the discharge chamber with different anode gas flow rate.The relationship between the magnetic flux density and the discharge voltage,the propellant utilization efficiency and the ion production cost of the thruster was obtained.The mapping relationship between the magnetic flux density and the flatness of ion beam was obtained by using Faraday probe device.The results showed that the output thrust of 10 cm continuous variablethrust ion thruster increases with the increase of magnetic flux density,and the relationship between discharge voltage and magnetic flux density presents a nonlinear quadratic polynomial relationship.With the increase of magnetic flux density within a certain range,the propellant utilization efficiency increases,the ion production cost decreases gradually,and the flatness of ion beam increases correspondingly.However,if the magnetic flux density is too large,the performance of discharge chamber changes unexpectedly,and the plasma becomes unstable.The research will certainly provide technical support for the construction of the thrust control algorithm of the 10 cm continuous variable-thrust ion electric propulsion system and the magnetic circuit optimization of the thruster.