Systems analysis, modeling, simulation, and signal processing aspects of coordinated experimental and modeling investigations of high-speed gas discharge switch breakdown behavior

Summary form only given, as follows. The authors have been engaged in coordinated experimental, analytical, and computer modeling investigations to better characterize the early-time turn-on behavior of high-speed gas discharge switching for a selected range of operating parameters. The investigations have focused on quantifying the first few nanoseconds of plasma closing switch turn-on behavior as a function of key operational parameters (e.g., gas type, gas pressure, gap length, drive circuit impedance, etc.). Various gas species (e.g., hydrogen, nitrogen, SF/sub 6/, helium) have been studied experimentally over a pressure range of 0.1-bar to 50-bar using several high-speed discharge switching test fixtures of conical configuration with differing discharge circuit impedances. The near-term objective has been to characterize, through complementary experimental measurements and modeling, the macroscopic turn-on behavior of high-speed gas closing switches under a selected range of operational conditions having practical interest. Longer-term goals of this work are to bring about I improvements in modeling, design, and operational performance of high-speed gas switches for use in ultra-fast, short-pulse-duration, low-impedance circuit applications. Under such conditions, the voltage collapse time and energy losses within the switch itself can significantly degrade overall system performance. This collaborative effort has involved the use of high-resolution 3-D time-domain electromagnetic modeling, simulation, and digital signal processing to complement and extend the available experimental data. Work has also been underway to develop and incorporate improved discharge channel physics modeling. This paper specifically describes the systems modeling, signal processing, and data analysis aspects of the investigations, and reports on results achieved to date. A related paper being submitted to this conference deals more specifically with certain aspects and recent result- of the experimental investigations.