气体介质与脉冲参数对纳秒脉冲放电特性的影响

Influence of Gas Medium and Pulse Parameters on Nanosecond Pulse Discharge Characteristics

在定容弹内研究了介质压力、介质成分以及纳秒脉冲电源所控制的4个脉冲参数(脉冲输出电压、脉冲宽度、脉冲次数、脉冲频率)对纳秒脉冲放电过程的影响.结果表明:介质压力上升,首个脉冲和首个击穿脉冲的电极释放电压均上升,高压维持数增加,首个击穿脉冲的放电能量上升.增大脉冲输出电压可以减少高压维持数,但不改变击穿电压.增大脉冲宽度同样不改变击穿电压,但明显提升了首个击穿脉冲的放电能量.改变容弹内介质中CO_(2)的浓度,首个脉冲和首个击穿脉冲的释放电压、放电能量、高压维持数均增加.升高脉冲频率增强了在不同环境条件下脉冲击穿能力,但不影响能量注入总量.在确保击穿的情况下,脉冲次数的增加则能显著增大脉冲注入的能量,增大粒子云团面积,有助于实际点燃过程.

In a constant volume chamber,the influences of gas pressure,gas composition and four pulse parameters,i.e.pulse output voltage,pulse width,number of pulses,pulse frequency,which are controlled by the nanosecond pulse power supply,on the nanosecond pulse discharge process were studied.Experimental results show that the electrode release voltage of the first pulse and the first breakdown pulse,the number of high-voltage pulses,and the discharge energy of the first breakdown pulse increase with the rise in gas pressure.The increase of power supply output voltage reduces the number of high-voltage pulses without changing the breakdown voltage.The increase of pulse width does not change the breakdown voltage but significantly increases the discharge energy of the first breakdown pulse.The release voltage,discharge energy of the first pulse and the first breakdown pulse and the number of high-voltage pulses are increased by changing the concentration of carbon dioxide in the constant volume chamber.The increase of pulse frequency enhances the breakdown ability under different gas environments but does not affect the total amount of energy injected.On the premise of breakdown,the increase of pulse number can significantly increase the pulse injection energy and particle cloud area,which is useful for the actual ignition process.