Progress in Experimental Study of Plume Plasma Discharge Characteristics of the Hollow Cathode

With the continuous maturation and sustained application of electric propulsion technology, electric propulsion is becoming the preferred choice of space propulsion for deep space exploration missions with its high specific impulse advantage. Among them, ion and Hall thrusters, as the main propulsion devices, have been widely used. As the core components of ion and Hall thrusters, the high-energy ion sputtering triggered by the unstable plasma discharge of the hollow cathode plume exacerbates its corrosion failure and performance deterioration, which ultimately leads to the inability of the thrusters to ignite properly. Therefore, in order to ensure that the electric thruster has a long life and high reliability, this paper thoroughly studied the steady-state discharge characteristics of the hollow cathode and the plume oscillation characteristics, summarized and analyzed the main influencing factors. It achieved effective avoidance of the plume oscillation phenomenon by adjusting the cathode component design parameters, discharge parameters, and factors such as the gas supply mode and the magnetic field potential shape. This slows down the sputtering corrosion of the cathode component and extends the cathode working life. This ensures that the thruster can maintain a long life and highly reliable and stable operation.