Optimization of the Energy Distribution in Ablative Pulsed Plasma Thrusters

Abstract

Regarding space missions, electric propulsion efficiency is a hot topic due to the development of microsatellites. However, ablative pulsed plasma thrusters, which were the first electric propulsion devices, suffer from low efficiency (less than 10%). In this study, a double-discharge ablative pulsed plasma thruster that allocates the total energy to two capacitors and discharges at different locations was designed to improve the efficiency of these thrusters. The performance of the double-discharge ablative pulsed plasma thruster was calculated based on experimental results under four different working conditions. The results showed that the double-discharge ablative pulsed plasma thruster performance was significantly improved relative to that of a regular ablative pulsed plasma thruster, in which the total energy is stored in a single capacitor. When the total energy remains constant (2.25 J), as the energy allocated to the secondary capacitor increases, the thrust efficiency and specific impulse increased significantly, respectively. Finally, theoretical analysis combined with the experimental results revealed the successful separation of the ablation–ionization and acceleration processes for the double-discharge ablative pulsed plasma thruster, contributing to the improvement of its performance. This research provides a reference for the design of high-performance ablative pulsed plasma thrusters.