Review on gas switches developed for fast linear transformer driver

The research of inertial fusion energy (IFE) based on Z pinch physics has necessitated the development of fast linear transformer drivers (LTDs). The requirements for gas switches that play a crucial role in fast LTDs are firstly presented, and the methods to attain low pre-fire rate, low trigger voltage and long life of the switches are described. Then the worldwide development of the fast LTD switches are summarized. Townsend and Streamer theories are briefly described to explain the switch discharge process, the switch self-breakdown property is analyzed according to Paschen principle and Meek criterion, and the influence of the number of stages and the uniformity of voltage distribution among stages on the switch static property is presented. The measures to decrease the trigger voltage of the switches deduced from the expression of the breakdown delay time, are put forward. Some techniques for suppressing electrode erosion, and the long term research strategy for the gas switches of fast LTDs are finally discussed.