Design and Development of Prototype Low Power Glow Discharge Hollow Cathode for Plasma Thruster

A low-power glow discharge hollow cathode neutralizer is presently under development at the ZAP Lab, Department of Aeronautics and Astronautics, National Cheng Kung University, Taiwan. This neutralizer cathode operates based on glow-discharge DC plasma generation, without the inclusion of thermionics material. The glow discharge hollow cathode design exhibits robustness and compactness while consuming relatively low power. Notably, the cathode functions effectively at a discharge voltage range of approximately 860-915V with a current of 0.05A, maintaining stable operation within the 200-300V voltage range. Moreover, the cathode successfully accommodates gas propellant feed rates varying from 1 to 10 standard cubic centimeters per minute (sccm) of Argon. Furthermore, the cathode demonstrates the capability to operate even with orifice power cut off and effectively ignite the ion thruster.