Special issue on selected papers from CEPC 2021

Electric propulsion technology is the most active professional technology in the field of space propulsion in recent years. China began the research of electric propulsion technology in the 1970s, and entered the stage of rapid development after 2000. It has successively completed the principle research, technical breakthrough and ground test verification. Driven by the increasing demand for space missions, various new types of electric propulsion are emerging. At the same time, the applicable fields of electric propulsion are also expanding, which promotes the proposal and realization of new space tasks that are difficult or even impossible for traditional chemical propulsion. The age of electric propulsion has arrived.

During the period of rapid development in the fundamental research of electric propulsion technology and space application, the 17th China Electric Propulsion Conference (CEPC 2021) was held in Lanzhou, Gansu Province from July 29 to July 30, 2021. It was hosted by the Electric Propulsion Professional Committee of Chinese Society of Astronautics, the Key Laboratory of Vacuum Technology and Physics, the Key Laboratory of Space Environmental Material Behavior and Evaluation Technology, and organized by Lanzhou Institute of Physics. The conference attracted researchers from more than 50 universities, research institutes and aerospace industry departments in China. The conference included eight plenary talks, six invited reports and 129 oral presentations, covering nine topics, including (1) electric propulsion system design and relative mission planning; (2) on orbit application and flight demonstration of electric propulsion system; (3) research progress of electric propulsion technology route; (4) new electric propulsion technology and concept; (5) power processing unit, propellant storage and supply unit, control unit, thrust vector control device and other technologies of electric propulsion system; (6) new materials, devices and key components of electric propulsion technology and self-control; (7) electric propulsion test, test and diagnosis technology; (8) basic theory, model analysis and numerical simulation of electric propulsion; (9) prospect of mass production of electric propulsion products and industrialization of electric propulsion technology for commercial aerospace. The conference aimed to exchange and display the latest research and application progression in the field of electric propulsion in China, to promote the development of electric propulsion and its plasma application disciplines, and to promote the progress of space power technology and aerospace science and technology.

This special issue is organized from the papers presented in the CEPC 2021. Interested readers can find the papers concerning investigations of plume thermal effect of the LIPS-200 ion thruster [1], the characteristics of non-Maxwellian magnetized sheath in Hall thruster acceleration region [2], the effect of anode axial position on the performance of a miniaturized cylindrical Hall thruster with a cusp-type magnetic field [3], early experimental investigation of the C12A7 hollow cathode fed on iodine [4], experimental study on the degradation of the C12A7 hollow cathode [5], numerical simulation of the start-up process of a miniature ion thruster [6], micro-impulse and plasma plume produced by irradiating aluminum target with nanosecond laser pulses in double-pulse scheme [7], simulation of liquid meniscus formation in the ionic liquid electrospray process [8], simulation of the helicon plasma source in magnetoplasma rocket engine [9], numerical study of effect of aft-loaded magnetic field on multiple ionizations in Hall thruster [10], and the characteristics of plasma in a novel laser-assisted pulsed plasma thruster [11]. These papers reflect the latest progress in electric propulsion technology in universities, research institutes and aerospace industry departments of China.

The guest editors would like to thank all the authors 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, Lanzhou Institute of Physics, and all the experts and scholars who participated in the conference. We hope that this special issue will promote and facilitate the fundamental study of electric propulsion and more extensive applications in space missions in the future.