空心阴极放电自脉冲现象的实验研究

Experimental Study of Self-Pulsing Phenomenon in Hollow Cathode Discharge

研究了氩气中圆柱形空心阴极放电的自脉冲现象.测试了空心阴极放电不同阶段的伏安特性及自脉冲频率和电流脉冲上升沿随放电平均电流、气压和电路电容的变化;讨论了自脉冲的形成机理.结果表明,自脉冲现象出现在空心阴极放电的负阻特性阶段,并具有稳定的频率.自脉冲频率随平均电流的增加而线性增大,气压和孔径的乘积pD值对频率的影响与其大小有关,但电极间的并联电容不影响脉冲频率;电流脉冲上升沿几乎与平均电流、气压或并联电容无关.实验结果表明,自脉冲现象是空心阴极本身的一种特征放电过程.

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.