Experimental And Theoretical Study On The Two.stage Pulsed Plasma Thruster

Pulsed plasam thrusters(PPTs)are highspecific impulse,reliable,relatively simple,inexpensive,and able to operate at less than 10 W,makingthem useful for applications such as altitude control for satellites and propulsion formicrosatellites and nanosatellites.However,the thrust efficiencies of PPTs are very low(usually <10%)compared with most other electric thrusters,such as ion thrusters and Hall thrusters.In the past 50 years,many researches were carried out to improve the PPT thrust efficiency,but make seldom process.In this paper,the discharge process of PPTs is studied,the Two.Stage PPT is put forward,aiming at improve the thrust efficiencies in PPTs and providding a reference for the design of high.performance PPTs.The energy distribution mechanism of an classical single discharge PPT is studied in this paper.The discharge parameters and the propellant ablated mass are measured to estimate the thrust performance parameters of the PPT.The energy distribution mechanism of the PPT is analyzed.The results show that the impulse bit,the specific impulse,and the thrust efficiency of the PPT increase as the capacitor voltage increased.However,in these four cases,the thrust efficiency is very low,less than 10%.Two.Stage Pulsed Plasma Thruster is designed in this paper.The energy of the Two.Stage pulsed plasma thruster is stored in two capacitors and disharges at difference space(electrodes).The discharge parameters of the PPT are measured to estimate the thrust performance parameters.The results show that the double discharge PPT has better performance on impulse bit,specific impulse,and thrust efficiency comparing with the single discharge PPT which has the same discharge energy.The impulse bit,the specific impulse and the thrust efficiency of the Two.Stage pulsed plasma thruster increase as the secondary capacitor voltage increased.The Two.Stage pulsed plasma thruster with longer insulation channel would have worse thrust performance.In particular,the specific impulse and the thrust efficiency improve a lot.Simulation of the Two.Stage pulsed plasma thruster is carried on in this paper.The PPT electromechanical model is employed to design the double pulse discharge model Simulation results of 4 cases are compared with the experiment results.Thrust performance of different prototype parameters is predicted by the model.