Guest Editors

Haibin TANG (湯海濱)1,Daren YU (于達(dá)仁)2,Haixing WANG(王海興)3 and Weizong WANG (王偉宗)3

1 School of Space and Environment, Beihang University, Beijing 100191,People’s Republic of China

2 Lab of Plasma Propulsion,Harbin Institute of Technology,Harbin 150001, People’s Republic of China

3 School of Astronautics,Beihang University, Beijing 100191,People’s Republic of China E-mail: whx@buaa.edu.cn

The development of electric propulsion has taken decades and in fact,began flight testing as early as the 1960s.However, it was initially slow to develop as an alternative to chemical propulsion systems due to the lack of available on-board electrical power for space vehicles.Since the turn of this century, the booming satellite market, and in particular for small satellites, has driven the demand for propulsion systems with high specific impulse, precisely adjustable thrust, long lifetime, and adaptable for different kinds of small vehicles.At the same time,Hall, ion, arcjet and other forms of electric thruster technologies have reached a mature level, the success of in-orbit testing further stimulated the applications of electric propulsion technology.In recent years, a number of commercial companies have proposed plans for small satellite constellations in low Earth orbit,providing broader opportunities for the development and application of electric propulsion technology.The age of electric propulsion has arrived.

In this period of rapid development of fundamental research and space applications of electric propulsion technology,the 16th China Electric Propulsion Conference (CEPC 2020) was held in Beijing on December 25–27, 2020, which was hosted by the Electric Propulsion Professional Committee of Chinese Society of Astronautics and organized by Beihang University.The conference attracted the participation of researchers from more than 50 universities,research institutes and aerospace industry across China.The conference contains 6 plenary talks, 20 invited talks, 92 oral presentations, which covers 10 topics, including (1) spacecraft mission planning and electric propulsion system applications;(2)arcjet,ion,Hall, PPT, MPD, VASIMR thruster technologies; (3) microwave, laser, RF and other electric propulsion application technologies; (4) microthrusters and electric propulsion devices for Cubesats applications;(5)new concepts,new principles of electric propulsion technologies; (6) electric propulsion plasma and electromagnetic basic theory, models and numerical simulations; (7) electric propulsion test and diagnosis technologies; (8) new materials, devices and key components technologies; (9) power supply, propellant storage and supply unit, control unit,thrust vector control device and other technologies used for electric propulsion systems; (10) electric propulsion plume effects on spacecraft and related protection technologies.The conference provided a good platform for academic exchange and communication, and laid the foundation for the future cooperation and development of electric propulsion technology.

This special issue in the journal ofPlasma Science and Technology(PST) is organized from the papers presented in the CEPC 2020.Interested readers can find that the papers concerning the performance and lifetime study of an ion thruster[1], matching characteristics of magnetic field configuration and chamfered channel wall in a magnetically shielded Hall thruster [2], far-field plasma characteristics of a low power Hall thruster[3],grid erosion of a field emission electric propulsion [4], sub-micron-Newton scale thrust measurement system for micro electric thrusters [5], arc anode attachment characteristics [6], magnetically levitated testbed with composite superconductor bearing for micro thrust measurement[7], the fast prediction method of SF-MPD performance based on a plasma equilibrium model [8], ablation characteristics of a laser-assisted pulsed plasma thruster with metal propellant [9], experimental study of an electrospray thruster based on porous media [10].These papers reflect the latest research progress on electric propulsion technology in universities, research institutes and aerospace industry of China.

The guest editors would like to thank all the authors who participated in the CEPC 2020 and in this special issue, the reviewers for their time and dedication,and for their thoughtful consideration of the papers as well as their excellent comments and suggestions.We thank the organizers of the conference, Beihang University, and all the experts and scholars who participated in the conference.Special thanks to the PST editorial team for providing the full support in the manuscript organization and review process.We hope that this special issue will promote and facilitate the fundamental study of electric propulsion thrusters and their more extensive applications in space missions in the future.