MPD thrusters hold considerable interest for future interplanetary missions, because they are characterized by thrust density values higher than other electric thrusters, unfortunately they have, at present, too much modest thrust efficiency (smaller than 40%) for allowing the operational use.
Centrospazio first and Alta afterwards have carried out theoretical and experimental research activities on MPD thrusters since the first 90s.
The main objective of the present work is to characterize a new pulsed-quasi-stationary, applied-field MPD thruster, designed during a previous thesis.
Through an extended experimental campaign, the thruster performance and general behaviour have been investigated for different operative conditions in terms of external magnetic field and propellant mass flow rate.
Measurements of electrical characteristic and thrust have been compared to numerical results from a performance model, partially validated on previous Centrospazio prototypes.
The comparison shows that the model is not able to correctly predict the power losses in the present device.
The performance parameters calculated from the experimental data show the expected trend, but the thrust efficiency is still rather limited.
At the same time the thrust balance has been modified and a new data processing has been elaborated in order to improve the accuracy in thrust measurement. A magnetic block has been implemented in the thrust balance; it keeps the thruster in a fixed position until few milliseconds before the thruster shot.
The thrust data obtained after the balance modification are affected by a much lower error than previous measurements