Operating Characteristics of Carbon Nanotube Neutralizer for Space Exploration Missions

Abstract

With the development of high-precision space exploration missions such as gravitational wave detection and Earth gravity field detection，the accuracy requirements of propulsion systems are further improved，and it is urgent to develop neutralizers with stable output of small current. In this paper，the working stability and electron extraction of carbon nanotube field emission neutralizer were experimentally studied. The current fluctuation characteristics before and after aging were tested， and spearman rank correlation test was used to analyze the correlation between background electric field and current fluctuation. Besides，three kinds of gate with different aperture were used to test the extraction characteristics of the neutralizer，and the influence mechanism of gate aperture on the performance of the neutralizer was analyzed. The experimental results show that aging treatment is helpful to improve the working stability of the neutralizer，and the background electric field of the emitter has a strong correlation with the instability of the emission current. The gate aperture has influence on both emission and extraction performance，and the 1 mm gate aperture has the best performance under experimental conditions. The results can provide some guidance for neutralizer configuration and structure design in propulsion system.

Keywords

carbon nanotube / neutralizer / stability / extraction rate

References

[1] 武迪，程林，王伟，等. 基于切换系统的小推力轨迹优化协态初始化方法[J]. 深空探测学报（中英文），2021，8（5）：529-533.
WU D，CHENG L，WANG W，et al. Low thrust trajectory optimization costate initialization method based on switching system[J]. Journal of Deep Space Exploration，2021，8（5）：529-533.
[2] 李海洋，宝音贺西. 小推力转移燃料消耗估计的机器学习方法[J]. 深空探测学报（中英文），2019，6（2）：195-200.
LI H Y，BAOYIN H X. A machine learning method for estimating fuel consumption in low-thrust transfer[J]. Journal of Deep Space Exploration，2019，6（2）：195-200.
[3] 陈昶文，武荣. 宽范围输入输出离子电推进屏栅电源的设计[J]. 深空探测学报（中英文），2020，7（4）：407-416.
CHEN C W，WU R. Design of ion-electric propulsion grid power supply with wide range of input and output[J]. Journal of Deep Space Exploration，2020，7（4）：407-416.
[4] 李永，丁凤林，周成. 深空探测推进技术发展趋势[J]. 深空探测学报（中英文），2018，5（4）：323-330.
LI Y，DING F L，ZHOU C. Development trend of deep space exploration and propulsion technology[J]. Journal of Deep Space Exploration，2018，5（4）：323-330.
[5] 李宗良，高俊，刘国西，等. 小行星探测电推进系统方案研究[J]. 深空探测学报（中英文），2018，5（4）：347-353.
LI Z L，GAO J，LIU G X，et al. Study on electric propulsion system for asteroid exploration[J]. Journal of Deep Space Exploration，2018，5（4）：347-353.
[6] PEDRINI D，MISURI T，PAGANUCCI F，et al. Development of hollow cathodes for space electric propulsion at sitael[J]. Aerospace，2017，4（2）：26.
[7] GOEBEL D M，KATZ I. Fundamentals of electric propulsion：ion and Hall thrusters[M]. Hoboken，New Jersey：Wiley，2008.
[8] 柳鹏，周段亮，张春海. 超顺排碳纳米管场发射电子源在射频离子微推进中和器中的应用[J]. 真空电子技术，2020（4）：23-27.
LIU P，ZHOU D L，ZHANG C M. Application of superlinear carbon nanotube field emission electron source in radio-frequency ion micropropulsion neutralizer[J]. Vacuum Electronics，2020（4）：23-27.
[9] ANDERSON G，ANDERSON J，ANDERSON M，et al. Experimental results from the ST7 mission on LISA Pathfinder[J]. Physical Review D，2018，98（10）：102005.
[10] TAKAO Y，KUGIMIYA A，NAGAI S，et al. Development of neutralizer with carbon nanotube cathode for small scale ion engine[C]//Proceedings of the 30th International Electric Propulsion Conference. Florence，Italy：IEPC，2007.
[11] YAMAMOTO N，MORITA T，OHKAWA Y，et al. Ion thruster operation with carbon nanotube field emission cathode[J]. Journal of Propulsion and Power，2019，35（2）：490-493.
[12] MARRESE-READING C，POLK J，MUELLER J，et al. In-FEEP thruster ion beam neutralization with thermionic and field emission cathodes[C]//Proceedings of the 27th International Electric Propulsion Conference. Pasadena，CA：IEPC，2001.
[13] SINGH L A，SANBORN G P，TURANO S P，et al. Operation of a carbon nanotube field emitter array in a hall effect thruster plume environment[J]. IEEE Transactions on Plasma Science，2015，43（1）：95-102.
[14] HE J W，LIU P，GAO R，et al. Research on the neutralization control of the RF ion micropropulsion system for the ‘Taiji-1’ satellite mission[J]. Plasma Science and Technology，2020，22（9）：094002.
[15] WALPOLE R E，MYERS R，MYERS S L，et al. 概率与统计[M]. 袁东学，龙少波，译. 北京：中国人民大学出版社，2016.
[16] FORBES R G. The Murphy–good plot：a better method of analysing field emission data[J]. Royal Society Open Science，2019，6（12）：190912.
[17] FORBES R G. Comments on the continuing widespread and unnecessary use of a defective emission equation in field emission related Literature[J]. Journal of Applied Physics，2019，126（21）：210901.
[18] 包研科. 数据分析教程[M]. 北京：清华大学出版社，2011：142-144.
[19] 夏明霞，颜宁，李红星. 外加电场作用下碳纳米管结构稳定性及结构修饰研究[J]. 物理学报，2007，56（1）：113-116.
XIA M X，YAN N，LI H X. Study of stucture stability and decoration of carbon nanotube under applied electric field[J]. Acta Physica Sinica，2007，56（1）：113-116.
[20] LIU J A，SUN Y，CHEN S C，et al. A study of coulomb explosion induced by freestanding carbon nanotube during field emission[C]//Proceedings of 2021 IEEE 21st International Conference on Nanotechnology. Montréal，Canada：IEEE，2021.
[21] BENJAMIN L C. Carbon nanotube field emission arrays[D]. Ohio：Air Force Institute of Technology，2011.
[22] 张强，陈泽祥，朱炳金，等. 碳纳米管场致发射中的空间电荷效应[J]. 发光学报，2008，29（3）：567-572.
ZHANG Q，CHEN Z X，ZHU B J，et al. Space charge effect in carbon nano-tube field emission[J]. Chinese Journal of Luminescence，2008，29（3）：567-572.