Experimental study of self-pulsing phenomenon in hollow cathode discharge

Self-pulsing phenomenon in cylindrical hollow cathode discharge in argon has been investigated experimentally. The voltage-current characteristics of the discharge, corresponding to different discharge stages, were measured. The self-pulsing frequency and current waveform were investigated under different operation conditions. The mechanism for the self-pulsing formation has been discussed. It is shown that the self-pulsing can be observed in the negative differential resistance region of hollow cathode discharge, and has the stable frequency (a few to tens of kHz). The frequency depends on the product pD of pressure and hole diameter and increases linearly with the average current. But it is not related to the capacitance in parallel with the discharge gap. The self-pulsing current has unchangeable rising time under various conditions. The experimental results indicate that the self-pulsing is a behavior controlled by the discharge process.