针对离子推力器服役过程中的非预期电击穿对可靠性的影响问题,首先进行了非预期电击穿的失效影响及综合风险评估,然后结合非预期电击穿导致的突发失效特征建立了基于δ冲击模型的离子推力器可靠性评估模型,最后以20 cm Xe离子推力器为例...针对离子推力器服役过程中的非预期电击穿对可靠性的影响问题,首先进行了非预期电击穿的失效影响及综合风险评估,然后结合非预期电击穿导致的突发失效特征建立了基于δ冲击模型的离子推力器可靠性评估模型,最后以20 cm Xe离子推力器为例,在收集地面试验历史数据的基础上计算了考虑非预期电击穿的离子推力器可靠度随服役时间的关系。另外,综合考虑了由于栅极系统性能退化导致的退化型失效和由于非预期电击穿导致的突发型失效共存的情形,对离子推力器的整机可靠性评估进行了分析讨论。展开更多
Space ion electric propulsion has been widely used in the north-south position maintenance and orbit transfer missions for high-orbit satellites.However,unexpected electric breakdown by ion electric propulsion systems...Space ion electric propulsion has been widely used in the north-south position maintenance and orbit transfer missions for high-orbit satellites.However,unexpected electric breakdown by ion electric propulsion systems is still a challenging problem that needs to be solved,as it affects reliability.Based on the analysis of in-orbit and ground test data of ion thrusters from simulation and experimental results,the main influencing factors of induced electric breakdown are clarified and the mechanisms of induced electric breakdown are analyzed.It is found that the main factors inducing breakdown are the voltage and electric field strength between the grids.In addition,by monitoring the waveform of plasma discharge,the temporal characteristics of breakdown can be defined as three stages of“breakdown-spark-loop response”.Thus,three kinds of engineering suppression methods for breakdown of static vacuum with periodic short-term heating,electrode surface polishing and sealing insulation with plasma,add energy suppression circuit are carried out,and the experimental results show that the electric breakdown frequency can be reduced by about 30%.展开更多
文摘针对离子推力器服役过程中的非预期电击穿对可靠性的影响问题,首先进行了非预期电击穿的失效影响及综合风险评估,然后结合非预期电击穿导致的突发失效特征建立了基于δ冲击模型的离子推力器可靠性评估模型,最后以20 cm Xe离子推力器为例,在收集地面试验历史数据的基础上计算了考虑非预期电击穿的离子推力器可靠度随服役时间的关系。另外,综合考虑了由于栅极系统性能退化导致的退化型失效和由于非预期电击穿导致的突发型失效共存的情形,对离子推力器的整机可靠性评估进行了分析讨论。
文摘Space ion electric propulsion has been widely used in the north-south position maintenance and orbit transfer missions for high-orbit satellites.However,unexpected electric breakdown by ion electric propulsion systems is still a challenging problem that needs to be solved,as it affects reliability.Based on the analysis of in-orbit and ground test data of ion thrusters from simulation and experimental results,the main influencing factors of induced electric breakdown are clarified and the mechanisms of induced electric breakdown are analyzed.It is found that the main factors inducing breakdown are the voltage and electric field strength between the grids.In addition,by monitoring the waveform of plasma discharge,the temporal characteristics of breakdown can be defined as three stages of“breakdown-spark-loop response”.Thus,three kinds of engineering suppression methods for breakdown of static vacuum with periodic short-term heating,electrode surface polishing and sealing insulation with plasma,add energy suppression circuit are carried out,and the experimental results show that the electric breakdown frequency can be reduced by about 30%.
