Influence of Different Energy Supply Methods on Performance of Ablative Pulsed Plasma Thrusters

For a certain configuration of ablative pulsed plasma thruster, changing the initial energy is an effective way to optimize the performance of the thruster. Different energy supply methods will not only affect the macro discharge characteristics and system performance of the thruster, but also affect the micro characteristics of the plasma in the discharge channel, the equivalent parameters of the discharge circuit, energy conversion efficiency and so on. In this study, the discharge characteristics, ablation characteristics and plasma motion characteristics of the thruster under different energy supply methods are analyzed experimentally and theoretically. The results show that using the method which includes increasing capacitance to heighten the initial energy of system under the same voltage, using a low-voltage, large-capacitor power supply method under the same initial energy, can effectively increase the impulse generated by Lorentz force and its proportion in the impulse bit. Moreover, the proportion of the ablative propellant effectively ionized and accelerated by Lorentz force increases. Therefore, the thruster has higher specific impulse and efficiency.

State-of-the-Art and Advancement Paths for Inductive Pulsed Plasma Thrusters

An inductive pulsed plasma thruster (IPPT) operates by pulsing high current through an inductor, typically a coil of some type, producing an electromagnetic field that drives current in a plasma, accelerating it to high speed. The IPPT is electrodeless, with no direct electrical connection between the externally applied pulsed high-current circuit and the current conducted in the plasma. Several different configurations were proposed and tested, including those that produce a plasma consisting of an accelerating current sheet and those that use closed magnetic flux lines to help confine the plasma during acceleration. Specific impulses up to 7000 s and thrust efficiencies over 50% have been measured. The present state-of-the-art for IPPTs is reviewed, focusing on the operation, modeling techniques, and major subsystems found in various configurations. Following that review is documentation of IPPT technology advancement paths that were proposed or considered.