Study on Coupling Characteristics of Hall Thruster Abnormal Ignition

ABSTRACT This study conducted systematic experiments to investigate abnormal ignition in Hall thrusters. The dynamic characteristics of electrical parameters during ignition were monitored using a multi‐probe diagnostic system. The experiments revealed that abnormal ignition occurs earliest and most intensely in the coupling region. This can be identified via housing and probes positioned in this area, where plasma demonstrates azimuthal uniformity and axial consistency during normal ignition. Conversely, abnormal ignition displays marked spatial asymmetry. Experimental alterations in thruster and cathode parameters demonstrated that increased anode voltage elevates electron temperature through enhanced electric field energy, consequently boosting ionization rates and space potential. An increase in keeper current suppresses initial abnormal ignition but may exacerbate plasma disturbance if excessive. In conclusion, the primary distinction between abnormal and normal ignition lies in variations within the coupling region.