Numerical Study for Obtaining the Optimum Conditions for Plasma Channel Formation in a Rail-Gap Closing Switch

The triggering discharge behavior of the rail gap influences the jitter of discharge delay and inductance of the spark switch due to the formation of multiple spark channels in the rail-gap switch, which is related with the development of avalanche in the discharge process under the nanosecond triggering pulses. In this paper, the PIC/MCC method is used to investigate the avalanche development under a triggering pulse. A model of intershielding is proposed in the PIC/MCC method considering the effect of the space charges. From the simulation and experimental results, it has been clarified that the avalanche process can be controlled by the statistical delay time of the effective primary electrons. The intershielding model can also explain the effect of the rise time of a triggering pulse on the avalanche development.